Thermal characteristics of poly (DL-lactic acid) microspheres containing neurotensin analogue.

The thermal characteristics of poly (DL-lactic acid) (DL-PLA) microspheres containing a hexapeptide (NA: H(CH3)-Arg-Lys-Pro-Trp-tert-Leu-Leu-OEt) with neurotensin activity were investigated. PLA microspheres with a drug content of 1.5-11.0% were prepared by a novel o/w (oil-in-water) solvent evaporation method. Both DL-PLA and NA were amorphous in form, and an increase in heat capacity at glass transition temperature (Tg) of the polymer was observed in DL-PLA microspheres containing NA. The Tg of DL-PLA (PLA2000 bulk) was 307.8 K, while Tg of microspheres containing NA (content 6.0%) shifted to 321.2 K. The Tg of PLA2000 microspheres was found to increase with an increase in the content of NA, and its increasing tendency reached a plateau at an NA content of greater than 6%. The apparent activation energy of glass transition of PLA2000 bulk and the microspheres was calculated to be 86.3 and 99.3 kcal/mol, respectively. As a result of the release test after storage at 4 degrees C and 40 degrees C for 1 month, nearly the same release profiles of NA from PLA2000 microspheres were found. The release rate of NA after the initial release became slow after storage at 45 degrees C for 1 month. This may be attributed mainly to a decrease in surface area caused by the formation of agglomerates of PLA2000 microspheres under conditions near Tg.


Structural analysis of the N-linked oligosaccharides from human urinary trypsin inhibitor.

The N-linked oligosaccharides from human urinary trypsin inhibitor were purified and their structures were investigated by compositional analysis, the two-dimensional sugar map method and 500 MHz 1H-NMR. The results revealed that they were composed of disialosyl, monosialosyl and asialosyl oligosaccharides, which have the common biantennary core structure; Gal1-4GlcNAc1-2Man1-3(Gal1-4GlcNAc1-2Man1-6)M an1-4GlcNAc1-4GlcNAc.


Molecular design of biologically active compounds based on platelet activating factor (PAF): 7-oxabicyclo[2.2.1]heptane system as a strong antagonist of PAF.

7-Oxabicyclo[2.2.1]heptane system was designed based on the PAF structure. Among four stereoisomers synthesized, the diexo derivative turned out to be a new and strong antagonist of PAF.


Intravenous nifedipine for prevention of myocardial ischaemia after coronary revascularization.

We sought to determine the pharmacokinetic and pharmacodynamic behaviour of a continuous infusion of nifedipine given for prevention of myocardial ischaemia following coronary artery bypass graft (CABG) surgery. Patients scheduled for elective CABG, who had good left ventricular function, were included. Only normotensive patients who did not require treatment with vasoactive drugs and were bleeding less than 100 ml.hr-1 following surgery were included. The patients were randomly distributed into two groups: a control group not receiving any treatment and a treated group receiving a bolus (3 micrograms.kg-1.min-1 for 5 min) and maintenance (0.2 micrograms.kg-1.min-1) infusion of nifedipine, starting upon arrival in the recovery room and continuing for four hours. Patients given nifedipine were compared with control patients in order to determine the effects of nifedipine on haemodynamic function and on the postoperative incidence of hypotension, hypertension, myocardial ischaemia and infarction. Continuous 2-lead Holter monitoring was used to detect myocardial ischaemia. Infarction was diagnosed by 12-lead ECGs and by assessment of the MB-isoenzyme creatine kinase. The infusion of nifedipine rapidly achieved and maintained plasma concentrations between 30 and 40 ng.ml-1. The pharmacokinetic studies revealed a systemic clearance of nifedipine of 0.371 +/- 0.101 L.hr-1.kg-1, an apparent volume of distribution of 0.764 +/- 0.288 L.kg-1 and an elimination half-life of 1.4 +/- 0.6 hr. No correlation was found between plasma concentration of nifedipine and mean arterial pressure (MAP). The incidence of postoperative hypotension (MAP < 70 mmHg) and hypertension (MAP > 100 mmHg) was comparable between the groups. All haemodynamic variables were similar in both groups during the study period. Of 23 patients who received nifedipine, none showed evidence of ischaemia within six hours of starting the infusion. During the same period, five of 24 patients in the control group had ST-segment deviation suggestive of myocardial ischaemia (P = 0.05, Fisher's exact test). Three patients in the control group and none in the nifedipine group suffered perioperative myocardial infarction (P = NS). In conclusion, the continuous infusion of nifedipine used in this study is safe and reduces the incidence of myocardial ischaemia in normotensive patients with good left ventricular function following CABG. Further studies of larger number of patients are required to determine the role of calcium entry blockers following coronary artery surgery.


Different effects of prostacyclin and phentolamine on delivery-dependent O2 consumption and skin microcirculation after cardiac surgery.

Inadequate tissue oxygen uptake autoregulation has been reported during the first hours after extracorporeal circulation for cardiac surgery. In the present study, we examined whether a dependence of oxygen consumption (VO2) on oxygen delivery (DO2) can be detected 24 hr after cardiac surgery using two different vasodilating agents. Cardiac output in triplicate was measured by thermodilution. Oxygen saturation of arterial and mixed venous blood was measured using a CO-oximeter. Oxygen consumption was assessed from the reverse Fick equation. In addition skin blood flow was assessed continuously by laser Doppler flowmetry. To investigate the VO2/DO2 relationship in 15 patients an increase in cardiac output and DO2 of at least 15% was achieved by systemic vasodilatation with iv prostacyclin (5-10 ng.kg-1.min-1) or phentolamine (5-10 g.kg-1.min-1). Infusion of phentolamine produced a 29 +/- 2% (mean +/- SE) increase in DO2 which was associated with a 20 +/- 6% increase in VO2. In contrast, prostacyclin produced a 22 +/- 3% increase in DO2 without change in VO2. Phentolamine did not alter skin microvascular blood flow, whereas prostacyclin increased skin microvascular blood flow by 33 +/- 3%. The results of the present study demonstrate a supply-dependency of VO2 in clinically stable patients 24 hr after cardiac surgery, suggesting the presence of an inadequate tissue O2 uptake autoregulation. The type of the vasodilator used to increase DO2 seems to play an important role in detecting such a supply-dependency of VO2, as well as changes of skin blood flow.


Predicting arterial oxygenation during one-lung anaesthesia.

Eighty patients undergoing elective thoracotomy were studied to assess the possibility of predicting arterial oxygenation (PaO2) during one-lung anaesthesia (OLA). The first 50 patients were studied retrospectively. The method of multiple linear regression was used to construct a predictive equation for PaO2 during OLA. Potential predictors of PaO2 during OLA which were considered were: age, side of operation, preoperative pulmonary flow rates, preoperative and intraoperative PaO2 during two-lung ventilation. The three most significant predictors for PaO2 during OLA were: side right of operation (P < 0.05), preoperative FEV1% (P < 0.01) and intraoperative PaO2 during two-lung ventilation (P = 0.0001). The predictive equation for PaO2 after ten minutes of OLA was: PaO2 = 100 - 72 (side) - 1.86 (FEV1%) + 0.75 (two-lung) PaO2; (for side insert 0 for left-sided thoracotomy and 1 for right-sided thoracotomy). The remaining 30 patients were studied prospectively and the predicted PaO2 correlated with the observed PaO2 after ten minutes of OLA (r = 0.73, P < 0.01). Four of 30 patients had a predicted PaO2 at ten minutes of OLA < 150 mmHg. Of these, 2/4 subsequently required abandonment of OLA for pulse oximetric saturation < 85%. We conclude that although it is not possible to predict an individual patient's PaO2 during OLA with a high degree of accuracy, it is possible, before the initiation of OLA, to identify those patients whose arterial oxygenation is likely to decrease to low levels during OLA.


Pressure controlled-inverse ratio ventilation and pulmonary gas exchange during lower abdominal surgery.

Although pressure controlled-inverse ratio ventilation (PC-IRV) has been used successfully in the treatment of respiratory failure, it has not been applied to the treatment of respiratory dysfunction during anaesthesia. With PC-IRV the inspiratory wave form is fundamentally altered so that inspiratory time is prolonged (inverse I:E), inspiratory flow rate is low, and the peak inspiratory pressure is limited. Positive end-expiratory pressure (PEEP) can be applied and the mean airway pressure is higher than with conventional ventilation. To assess the clinical efficacy of this new mode of ventilation we studied ten patients having lower abdominal gynaecologic surgery in the Trendelenburg position under general anaesthesia. Pulmonary O2 exchange was determined during four steady states: awake control (AC), after 30 and 60 min of PC-IRV during surgery, and at the end of surgery. Patients' lungs were ventilated with air/O2 by a Siemens 900C servo ventilator in the PC-IRV mode with an I:E ratio of 2:1 and 5 cm H2O of PEEP. The FIO2 was controlled at 0.5 and arterial blood gases were used to calculate the oxygen tension-based indices of gas exchange. There were significant increases of (A-a) DO2 at 30 and 60 min (41 and 43%). These changes were less than those reported in a previous study using conventional tidal volume ventilation (7.5 ml.kg-1) and were similar to those in patients whose lungs were ventilated with high tidal volumes (12.7 ml.kg-1). Thus, in this clinical model of compromised gas exchange, arterial oxygenation was better with PC-IRV than with conventional ventilation, but not better than with large tidal volume ventilation.


Early extubation of the trachea after repair of secundum-type atrial septal defects in children.

To investigate the role of anaesthetic management in early extubation of the trachea in children after closure of a secundum-type atrial septal defect (ASD II), a retrospective chart review for a two-year period was performed. We identified 36 children who underwent surgical repair of an isolated ASD II. In 19 children (53%) the tracheas were extubated in the operating room immediately after surgery and in 17 patients (47%) the tracheas remained intubated and the lungs were ventilated in the Intensive Care Unit. There was no difference in age (69.5 +/- 33.8 vs 72.9 +/- 45.0 mo) or weight (19.5 +/- 8.1 versus 20.5 +/- 12.7 kg) between the two groups (mean +/- SD). Children in the extubated group had a shorter duration of cardiopulmonary bypass (43.4 +/- 7.8 min) than those remaining intubated (31.7 +/- 12.7 min) (P < 0.05). The children whose tracheas were extubated early received a lower perioperative fentanyl dose (5.9 +/- 6.4 micrograms.kg-1) than those remaining intubated (35.1 +/- 8.5 micrograms.kg-1). Those children in the extubated group had a lower hourly requirement for morphine by infusion (13.6 +/- 5.7 vs 18.2 +/- 5.4 micrograms.kg-1.hr-1) and a shorter stay (20.5 +/- 3.7 versus 29.0 +/- 11.2 hr) in the Intensive Care Unit. Re-intubation of the trachea was not required in any of the children and no deaths occurred. Early extubation after ASD II repair is safe and, given the results of this study, may offer certain advantages over prolonged intubation and ventilation in these children.


Measuring recovery from general anaesthesia using critical flicker frequency: a comparison of two methods.

Critical flicker frequency (CFF) is the frequency at which a flickering light appears steady. It is a sensitive measure for assessing recovery from anaesthesia. The CFF is almost always determined with the method of limits by which the flickering frequency is progressively decreased (or increased) until the patient reports a change from fusion to flicker (or flicker to fusion). This method has two disadvantages: it is influenced by the response bias (i.e., the subjective criterion used by the subject to decide that flicker is present or absent) and by the response delay (i.e., the interval between the perceptual change and the response). To avoid these problems, the method of forced choice is recommended. For each trial, the subject observes the light during two short successive periods. The light flickers during only one period, according to chance. The patient must indicate the period during which flickers occur. If uncertain, the patient has to make a guess. The aim of this study was to compare the two methods for assessing recovery from general anaesthesia. Two induction agents were used to obtain different recovery profiles. Twenty patients undergoing uncomplicated surgery lasting less than two hours were tested. They received either thiopentone or midazolam for induction, according to a randomized design. Vecuronium was used to facilitate tracheal intubation and anaesthesia was maintained with fentanyl, isoflurane and nitrous oxide. The CFF was measured before induction and at 60, 120 and 180 minutes after arrival in the recovery room. The person measuring CFF was unaware of the induction agent used.(ABSTRACT TRUNCATED AT 250 WORDS)


Preadmission anaesthesia consultation clinic.

Many surgical procedures are delayed or cancelled due to inadequate preoperative assessment and preparation. We describe the case referral pattern and efficiency of our preadmission anaesthesia consultation clinic, which was designed to minimize this problem. Data were collected prospectively on the first 400 patients referred to the clinic. Sixty per cent of referrals were related to the cardiovascular system, in particular coronary artery disease (27%). Eighty-one per cent of referrals were considered appropriate. With ideal functioning of the clinic, delays and cancellations could potentially be reduced to 0.75% and 1.5% of cases respectively. The clinic was well accepted and appreciated by patients. We conclude that this represents a potential important reduction in hospital costs and improvement in operating room efficiency.


MAO inhibitors and coronary artery surgery: a patient death.

The mechanisms of action of monoamine oxidase inhibitors (MAOIs) suggest that patients taking them may respond with hyper- or hypotension when undergoing coronary artery surgery. We describe a case where MAOIs were present and fentanyl and midazolam were the anaesthetic agents used. The anaesthesia and surgery were performed without incident. Postoperative ICU care was complicated by hypertension, hyperthermia, and severe shivering followed by hypotension resistant to therapy and finally death. Diagnoses of pulmonary embolism and sepsis were unproven and may have played a role. The MAOIs may also have played a role. Reactions in patients while taking both meperidine and MAOIs are unusual and animals react differently from humans to a combination of MAOIs and narcotics. There are only five reported cases where fentanyl was given to patients on MAOIs. We conclude that, until there is more information, MAOIs should be discontinued, if possible, before surgery in which catecholamines may be needed.


Wenckebach type heart block following spinal anaesthesia for caesarean section.

A case is described of complete heart block during spinal anaesthesia for Caesarean section in a fit 23 yr-old-woman. This developed shortly after the institution of the block, with the height of the block below T5 and in the absence of hypotension. The patient was resuscitated successfully with vagolytic and alpha-agonist drugs. A Wenckebach block persisted for a short period postoperatively. The importance of instituting monitoring before the beginning of anaesthesia and the immediate availability of atropine and alpha-agonists before the initiation of spinal anaesthesia is stressed.


Allopurinol administered prior to hepatic ischaemia in the rat prevents chemiluminescence following restoration of circulation.

Oxygen-derived free radicals produced during reperfusion may be responsible for the disturbed pathology which follows prolonged ischaemia. Measurement of hepatic chemiluminescence (low level light emission resulting from the energy released during chemical reactions of free radicals) allowed determination of whether allopurinol could prevent formation of oxygen-derived free radicals during reperfusion of the ischaemic liver. While control animals demonstrated a burst of light emission shortly after reperfusion, the rats pretreated with allupurinol showed no evidence of chemiluminescence during either ischaemia or reperfusion. It is concluded that allopurinol may modify reperfusion-induced free radical formation and possibly ameliorate the organ damage which can follow ischaemia.


[Respiratory effects of moderate hypothermia (36 degrees C-28 degrees C) in dogs under halothane anesthesia].

Changes in systemic haemodynamic variables (mean arterial pressure, MAP; heart rate, HR; cardiac output, Qc), in oxygen consumption, VO2, and in ventilation (minute ventilation, V; respiratory frequency, f; tidal volume, VT; and arterial blood gases) with particular attention to respiratory times (duration of inspiration, TI; duration of expiration, TE; duration of the breathing cycle, TTOT), to respiratory timing (TI/TTOT) and respiratory drive (VT/TI) were studied during moderate progressive hypothermia (36 degrees C to 28 degrees C) during stable halothane anaesthesia (MAC = 1.5) in six dogs. MAP, HR and Qc decreased; V and f decreased, the decrease in f being correlated with that in temperature (r = 0.66; P < 0.01). Tidal volume did not change. The PaO2 and pHa decreased while PaCO2 increased slightly. The decrease in ventilation was related to changes in respiratory times (TI and TE) which increased (TE more than TI) and in respiratory drive (VT/TI which decreased due to the increase in TI). The relation between VT/TI and TI/TTOT changes was not constant during cooling. Changes in respiratory times and drive could be due to the effect of cold on medullar respiratory control.


Emergency management of the airway outside the operating room.

Successful emergency airway intervention incorporates the anaesthetist's basic skills in airway management with the knowledge of the special nature of the clinical problems that arise outside the operating room. While a thorough but rapid evaluation of the key anatomical and physiological factors of an individual patient may result in an obvious choice for optimal management, clinical problems often arise in which there is not an evident "best approach." In these less clear-cut situations, the anaesthetist may do well to employ those techniques with which she/he has the greatest skills and experience. At times, however, some degree of creative improvisation is required to care for an especially difficult problem.


Perioperative blood and blood component therapy.

This overview examines blood, blood components, their indications and contra-indications, from an anaesthetist's viewpoint. The dangers of any blood transfusion, including infection transmission and immune suppression, as well as the risks of massive and rapid transfusions, are discussed. Autologous predonation, intraoperative haemodilution and salvage are described to help prevent some of the risks of homologous blood transfusion. Preoperatively an acceptable individualised haemoglobin concentration should be calculated for each patient and a history for potential bleeding problems taken. In most patients perioperative anaemia does not adversely influence patient morbidity and mortality. However, if blood is required, 4 ml.kg-1 body weight of packed red blood cells will raise the patient's haemoglobin concentration by 1 g.dl-1. The bleeding time as a test of platelet function does not predict perioperative blood loss. However, it remains a useful test in patients with a known bleeding problem or in operations where even small amounts of bleeding increase the surgical difficulty and patient morbidity. If bleeding is due to thrombocytopaenia it is usually slow enough to allow time to check platelet number and function before ordering and transfusing them. Fresh plasma is a much overused product which should mainly be used for coagulation factor replacement, in adequate volumes (4-8 packs in dilutional coagulopathy). The well-informed anaesthetist should be better able to use blood products which, while they may be life saving, are neither innocuous nor inexpensive.


New possibilities for population control of cystic fibrosis.

Cystic fibrosis (CF), which is caused exclusively by mutation of a single gene, is inherited in autosomal recessive fashion and is the commonest such disorder in populations of Caucasian origin. Although much progress has been made during the last 50 years in its clinical management, with a corresponding improvement in the mean life expectancy in developed countries from a few months to a few decades, it remains incurable and a complete understanding of its biochemical basis is still being sought. Consequently, attention has been given to the possibility of screening for carriers of the defective gene, who represent up to 5% in some populations, so that they may be given appropriate genetic counselling. Whereas previously carriers were identified only when they became parents of affected children, in recent years carriers who were more distantly related to CF patients have often been identified by means of genetic linkage techniques. A new strategy for the control of CF at the population level is now proposed. It is based on the report of a joint WHO/ICF(M)A (International Cystic Fibrosis (Mucoviscidosis) Association) Task Force on CF which met in November 1990.


Community-based evaluation survey of immunizations in Burkina Faso.

A cluster sample survey was conducted in January 1989 in 3 provinces of Burkina Faso to evaluate an immunization programme (based on two contacts, providing inactivated poliomyelitis vaccine plus DPT) that had been launched in 1982-84. The objectives were to estimate neonatal tetanus (NNT) mortality and poliomyelitis prevalence in the study area. The target population (using the same sample of households comprised 2107 live infants born during the preceding year for the NNT survey, and 17,154 children aged 0-9 years for the poliomyelitis survey. The NNT mortality rate was 3.3 per 1000 live births, and the poliomyelitis prevalence rate was 2.8 per 1000 children aged 5-9 years. Dates of onset of poliomyelitis cases among children aged 0-9 years and the numbers of children at risk during the 10-year recall period, reconstituted with demographic indicators taken from standardized life-tables, were used to calculate the incidence rates of poliomyelitis. These rates could be compared in the 5-year period preceding the survey, and showed a decreasing trend consistent with routine surveillance data.


A large waterborne viral hepatitis E epidemic in Kanpur, India.

In 1991 the largest epidemic of viral hepatitis E yet reported occurred in Kanpur (population, 2.1 million), India. The incidence of icteric hepatitis from December 1990 to April 1991 among the inhabitants of 420 randomly sampled houses in seven of the city's 50 wards was 3.76% (138 out of 3666 individuals), i.e., an estimated 79,091 persons in the city as a whole were affected. The attack rate was higher for males than females (5.3% versus 3.3%; P = 0.013) and for adults than children aged < 10 years (4.26% versus 1.29%; P = 0.0006). The incidence of hepatitis was higher in those city wards that were supplied with drinking-water consisting of a mixture of river Ganges and tubewell water than in those wards supplied only with tubewell water (5.6% versus 1.2%; P = 10(-6)). In the mixed-water areas, the incidence decreased as the drinking-water source changed from only tap to both tap and handpump, to only handpump (7.8%, 6.8%, and 4.3% respectively; P = 0.023). None of the sera collected from 41 hepatitis patients during the epidemic showed evidence of hepatitis virus A or B. There were two peaks in the epidemic (in February and April 1991). The first peak was probably caused by faecal contamination of river water, indicated by water analysis data, and the second, by inadequate chlorination of water in a reservoir. There was no evidence of secondary intrafamilial spread.


WHO international quality assessment scheme for HIV antibody testing: results from the second distribution of sera.

The WHO international quality assessment scheme for human immunodeficiency virus (HIV) antibody testing has been established to monitor the quality of laboratory performance in testing for antibodies to HIV. Following a small trial distribution of specimens early in 1989, the second distribution was made in February 1990. A total of 20 specimens of sera, 10 of which contained antibodies to HIV-1, were sent to 103 laboratories located in the six WHO Regions. Participants were asked to test the specimens using their routine methods and to report to WHO their findings on each specimen for each diagnostic assay used and their interpretation of the HIV antibody status of each specimen. For the antibody-positive specimens, 98.2% of the results were interpreted as positive and 1.8% as indeterminate; no false-negative interpretations were reported. For the antibody-negative specimens, 90.3% of the results were interpreted as negative, 1.3% as positive, and 8.4% as indeterminate. Most of the indeterminate reports were associated with one particular specimen. A wide variety of diagnostic assays and combinations of assays were used. In terms of the technical results obtained rather than their interpretation, the assays appeared extremely reliable for the positive specimens, with 99.5% of assay results being recorded as positive, 0.17% as negative, and 0.34% as indeterminate.(ABSTRACT TRUNCATED AT 250 WORDS)


Exposure and health assessment during application of lambda-cyhalothrin for malaria vector control in Pakistan.

Icon 10 WP insecticide, a wettable powder formulation containing 10% lambda-cyhalothrin, was evaluated for possible adverse effects on the health of spraymen and villagers during treatment of dwellings for malaria vector control. Skin sensory effects and occasional coughing and sneezing in confined spaces were the only symptoms noted by the workers resulting from the handling and spraying of the insecticide. Absorption of lambda-cyhalothrin was estimated by determining its metabolites in urine and serum. The average amount of lambda-cyhalothrin absorbed by the workers per day (54 micrograms) represents less than 0.0001% (< 1 micrograms.kg-1.day-1) of the average daily amount of the substance handled. Only a small proportion of villagers showed detectable levels of lambda-cyhalothrin metabolites in their urine. Absorption of lambda-cyhalothrin from the formulation tested was therefore very low and, apart from the nuisance of skin sensory effects, there should be no risk to the health of workers or to the villagers whose dwellings are treated.


[Stability of P. Falciparum resistance to chloroquine between 1987 and 1989 in Mounana, Gabon].

Between 1987 and 1989 the trend in the chloroquine resistance of Plasmodium falciparum in the mining town of Mounana in south-eastern Gabon was studied in vivo and in vitro in 58 and 158 subjects, respectively, aged from 1 to 15 years. The tests used were a simplified variant of the standard WHO 7-day test for the in vivo study and the isotopic semi-microtest of chemosensitivity for the in vitro study. The health situation in 1989 showed no change from the 1987 situation, but an increase in febrile symptoms suggestive of malaria was observed in 1989. This observation may be linked to a decrease in the distribution of chloroquine since 1987, accompanied by the use of other antimalarials following the appearance of chloroquine-resistant strains. While the parasitological efficacy in vivo remained the same in 1989, there was a decrease in the proportion of strains resistant to chloroquine in vitro compared to 1987; likewise, the therapeutic efficacy as estimated from temperature readings was better in 1989 than in 1987: the modification of the prophylactic strategy since 1986 and the drop in chloroquine consumption since 1987 could be responsible for a stabilization of chloroquine resistance at Mounana. The authors consider it appropriate in this region to continue treating malaria in children with chloroquine (in a dosage of 25 mg/kg) and to use a second-line treatment in the event of the recurrence of malaria symptoms within the next two weeks.


Surveillance of Trypanosoma cruzi transmission by serological screening of schoolchildren.

The seroprevalence of Trypanosoma cruzi infection among children is a sensitive indicator for assessing the effectiveness of programmes for control of Chagas disease. In this study we report the result of a cross-sectional serological survey carried out among schoolchildren living in a poor rural area in central Brazil. Eluates of blood collected on filter-paper were tested for anti-T. cruzi antibodies using immunofluorescence, haemagglutination, and enzyme-linked immunosorbent assays. The overall seroprevalence of T. cruzi infection was 7.9%, which compared with the findings of the national survey carried out in 1975-80 indicates that a twofold-to-threefold reduction in prevalence has occurred over the last 10 years. This is consistent with a reduction of transmission in the area, probably related to vector control efforts. Based on our results, the incidence of new cases was estimated to be 44 per annum in the study region. In rural areas with a scattered population, surveillance of T. cruzi transmission by serological screening of children at school entry is more practical and economical than entomological evaluation for assessing both the risk of transmission in the community and the efficacy of vector control measures. A sample size of around 1000 schoolchildren is sufficient to detect prevalences as low as 2%, and such an approach would be practical and applicable to most areas where Chagas disease is endemic.


Characterization by isoenzyme electrophoresis of Trypanozoon stocks from sleeping sickness endemic areas of south-east Uganda.

An epidemic of sleeping sickness, which started in 1976 in a focus within the county of Luuka in Central Busoga, has spread to cover the three districts of Busoga and large parts of the neighbouring districts of Tororo and Mukono. Forty-three isolates of the subgenus Trypanozoon from Busoga and Tororo (27 from man, 9 from cows, 2 from pigs and 5 from tsetse flies) were compared by thin-layer starch-gel electrophoresis for seven enzymes. Thirty zymodemes were identified; 17 of them were found circulating in the human population. The zymodemes seen previously in Busoga were still circulating together with several new ones. Of the 16 isolates from cattle, pigs and tsetse flies, only two had the same profile, indicating a high degree of diversity. Two zymodemes from cows and a pig were identical to those found in man, implicating domestic stock in the transmission of human disease in south-east Uganda. A computer analysis of the results produced six main zymodeme groups. One comprised only isolates from man; two were composed of isolates from man, domestic animals and tsetse; and three consisted of stocks from domestic animals only. These groups quite probably indicate the different cycles of transmission involving man, tsetse fly and domestic stock.


Determinants of child nutrition and mortality in north-west Uganda.

An anthropometric survey of children aged 0-59 months in north-west Uganda in February-March 1987 indicated a high prevalence of stunting but little wasting. Use of unprotected water supplies in the dry season, prolonged breast-feeding, and age negatively affected nutrition; in contrast, parental education level improved nutrition. Mortality during the 12 months following the survey was higher among those who had low weight-for-age and weight-for-height, but children who had low height-for-age did not have higher mortality. Weight-for-age was the most sensitive predictor of mortality at specificities > 88%, while at lower specificity levels weight-for-height was the most sensitive. Children whose fathers' work was associated with the distillation of alcohol had a higher risk of mortality than other children. The lowest mortality was among children whose fathers were businessmen or who grew tobacco.


Practical screening priorities for hearing impairment among children in developing countries.

Routine screening for hearing impairment in childhood is now widespread in industrial countries, although there is considerable controversy over the most efficient techniques and procedures. In most developing countries, however, routine screening programmes for hearing impairment do not currently exist. The problems involved in implementing screening programmes in developing and industrial countries are very different, and in selecting screening procedures for a particular population the following factors have to be taken into consideration: the environmental test conditions; the availability of resources for equipment and the training of testers; the local attitudes towards disability; the level of hearing impairment that may cause handicaps; and the major types of pathology causing hearing impairment. We suggest that in developing countries children should be screened at school entry using a simple field audiometer and that the external ear be inspected for the presence of a discharge. There is an urgent need to develop reliable and simple screening procedures for infants and young children; where possible, all children should be screened for severe or significant hearing impairment before the age of 2 years. No screening should, however, be implemented until appropriate follow-up services are available.


Nutritional status of Brazilian children: trends from 1975 to 1989.

The prevalence of malnutrition among under-5-year-olds in Brazil fell by more than 60% between 1975 and 1989. The benefits were smaller for population strata that were more affected by malnutrition in the 1970s, i.e., children from the North and North-east regions and those from poor families in general. Regional and socioeconomic differentials in the prevalence of malnutrition therefore increased between 1975 and 1989. Trends in family income indicate extraordinary economic gains in the 1970s, some losses in the 1980s, and a modest net gain over the period 1975-89. The availability of sanitation, health, and education services, and the provision of preschool supplementary feeding programmes increased markedly in the 1970s and 1980s. Demographic trends were also positive, reducing the demand for services and programmes, increasing the economic efficiency of families, and concentrating the population in urban areas, where incomes, job opportunities, and social and material infrastructures are better. The observed nutritional improvement was therefore probably due to a moderate increase in family income associated with a substantial expansion in the provision of services and programmes, both of which were facilitated by favourable demographic trends. Also, the nutritional improvement was probably concentrated during the 1970s, while little, if any, occurred after 1980; prospects for the 1990s point to a stagnant situation. This is a reason for great concern particularly in the North and North-east regions of the country, where high rates of child malnutrition are still found.


A review of the stability and compatibility of antineoplastic drugs for multiple-drug infusions.

It is important that the stability of reconstituted parenteral antineoplastic agents be established, particularly in the context of ambulatory infusion systems for delivery. The stability of selected agents within each of the five classes of compounds (antimetabolites, alkylating agents, antibiotics, alkaloids and glycosides, and metals) is reviewed from the literature together with additional data from studies carried out using high-performance liquid chromatographic (HPLC) technology in clinically applicable volumes and concentrations for ambulatory infusion. The stability of reconstituted drugs varies from a few minutes (mecloethamine) to many months (FU). Compatibility data on two- and three-drug admixtures of cytotoxic agents are reported for a number of common multidrug regimens. Tabular presentation of the drug-drug compatibilities and incompatibilities is included along with a discussion of the mechanisms for drug-drug interaction. The use of a broad spectrum of compatible cytotoxic drugs is possible, including fluoropyrimidine-, anthracycline-, and platinum-based combinations, providing the capability of carrying out multidrug infusions for 4-7 days in an ambulatory delivery system.


Inhibition of fludarabine metabolism by arabinosylcytosine during therapy.

The active 5'-triphosphate of arabinosyl-2-fluoroadenine (F-ara-ATP) increases the anabolism of arabinosylcytosine (ara-C), whereas ara-C 5'-triphosphate inhibits the phosphorylation of arabinosyl-2-fluoroadenine (F-ara-A) in human leukemia cells in vitro. These interactions have a potential impact on drug scheduling. Clinical trials of relapsed leukemia in which fludarabine (F-ara-A 5'-monophosphate) and ara-C were given in sequence provided the opportunity to evaluate the effects of ara-C infusion on two sequelae: the pharmacokinetics of F-ara-A in plasma and that of F-ara-ATP in leukemia cells. First, F-ara-A pharmacokinetics were altered by ara-C infusion. This was visualized as a transient increase in F-ara-A plasma levels during the ara-C infusion that was given 4 h after fludarabine. The perturbation in F-ara-A plasma levels was dependent on the dose ara-C. Second, peak F-ara-ATP concentrations were lower in leukemia cells of patients who received ara-C in addition to fludarabine as compared with those who received fludarabine alone. The terminal half-life of F-ara-A in plasma and the half-life of intracellular F-ara-ATP were reduced after the ara-C infusion in a concentration-dependent manner. Studies using purified deoxycytidine kinase support the conclusion that the increase in plasma levels of F-ara-A is in part the result of an effective competition by ara-C for phosphorylation by this enzyme, leading to a perturbation of the pharmacokinetics of intracellular F-ara-ATP.


Prevention of doxorubicin-induced myocardial and haematological toxicities in rats by the iron chelator desferrioxamine.

Biochemical and histopathological evaluations of the protective effects of the iron-chelator desferrioxamine against the cardiac and haematological toxicities of doxorubicin in normal rats were carried out. A single dose of doxorubicin (15 mg/kg, i.v.) caused myocardial damage that manifested biochemically as an elevation of serum cardiac enzyme [glutamic oxaloacetic transaminase (GOT), lactic dehydrogenase (LDH) and creatine phosphokinase (CPK)] and cardiac isoenzyme levels and histopathologically as a swelling and separation of cardiac muscle fibers. Doxorubicin caused severe leucopenia and decreases in red blood cell counts and haemoglobin concentrations at 72 h after its administration. Desferrioxamine treatment (250 mg/kg, i.p.) carried out 30 min before doxorubicin administration protected the heart and blood elements from the toxic effects of doxorubicin as indicated by the recovery of levels of cardiac enzymes and isoenzymes and of red blood cell counts to normal values and by the absence of significant myocardial lesions. The findings of this study suggest that desferrioxamine can potentially be used clinically to prevent doxorubicin-induced cardiac and haematological toxicities.


Identification of metabolites of the antitumor agent d-limonene capable of inhibiting protein isoprenylation and cell growth.

Limonene has been shown to be an effective, nontoxic chemopreventive and chemotherapeutic agent in chemically induced rat mammary-cancer models. The present study characterized circulating metabolites of limonene in female rats and determined their effects on cell growth. Metabolism of limonene was analyzed in plasma extracts by gas chromatography. Rapid conversion of limonene to two major metabolites was detected. These metabolites comprised more than 80% of the circulating limonene-derived material at 1 h after administration and thereafter, whereas limonene itself accounted for only 15%. The metabolites were characterized by mass spectroscopy and infrared spectroscopy. The probable structures were synthesized, and identities were confirmed by comparison of retention times and mass spectra. The two major circulating metabolites of limonene were found to be perillic acid and dihydroperillic acid. We have previously reported that limonene, perillic acid, and dihydroperillic acid inhibit the posttranslational isoprenylation of p21ras and other 21- to 26-kDa cell-growth-associated proteins in NIH3T3 cells and in mammary epithelial cells. In the present study, perillic acid was found to inhibit cell growth in a dose-dependent manner. Thus, perillic acid and dihydroperillic acid, the two major circulating metabolites of limonene in the rat, are more potent inhibitors of protein isoprenylation than is limonene, and perillic acid is also a more potent inhibitor of cell growth. These data raise the possibility that the antitumor effects of limonene in vivo may be mediated via perillic acid and, perhaps, other metabolites.


Continuous-infusion fluorodeoxyuridine with leucovorin and high-dose interferon: a phase II study in metastatic renal-cell cancer.

A total of 25 patients with metastatic renal cancer were treated on a phase II protocol with 5 days of continuous-infusion fluorodeoxyuridine (FUDR), (0.1 mg/kg daily) together with high-dose oral leucovorin (100 mg 4 h) and daily x6 high-dose interferon-alpha 2b (30 x 10(6) IU/m2). Despite the good performance status of the patients and the inclusion of 14 previously untreated patients in the cohort, no response was observed among the 20 evaluable patients. Toxicities included high fever, moderate anemia, transient leukopenia, transient and mild elevations of transaminases, and moderate to severe nausea, vomiting, diarrhea, and mucositis. There were also two episodes each of confusion, fluid retention, and pancreatitis and one episode of increased creatinine levels. During the study three deaths occurred, two of which were possibly therapy-related. Despite previous reports of activity of FUDR in metastatic renal cancer, the present regimen cannot be recommended.


Red blood cell methotrexate and folate levels in children with acute lymphoblastic leukemia undergoing therapy: a Pediatric Oncology Group pilot study.

We enrolled children with acute lymphoblastic leukemia (ALL) in a Pediatric Oncology Group (POG) pilot study to monitor erythrocyte (RBC) methotrexate (MTX) and folate (F) levels before and during treatment. The mean value for RBCF at diagnosis was 0.86 +/- 0.46 nmol/ml RBC in the 214 patients who achieved remission and 1.21 +/- 0.74 nmol/ml RBC in the 10 patients who did not (P = 0.020). Folate levels tended to increase during remission induction, but they dropped following an intensive consolidation with methotrexate to levels that were sustained throughout chemotherapy treatment. Methotrexate levels reached mean values of approximately 0.15 nmol/ml RBC at the end of an intensive methotrexate consolidation, then fell to levels that were sustained throughout maintenance therapy. There was a weak correlation between improved event-free survival and higher RBCMTX levels after consolidation, but no correlation was found between improved survival and the level of RBCMTX or RBCF during maintenance therapy. A larger study with more complete data is needed to determine whether RBCMTX or RBCF might be useful in predicting event-free survival in patients with ALL.


Inhibition of growth factor binding, Ca2+ signaling and cell growth by polysulfonated azo dyes related to the antitumor agent suramin.

The ability of the polysulfonated antitumor drug suramin and six related polysulfonated azo dyes to inhibit the cell growth, platelet-derived growth factor (PDGF)-receptor binding, and intracellular Ca2+ signaling of Swiss 3T3 fibroblasts was studied. Some of the azo dyes were more potent inhibitors of PDGF binding than was suramin. The concentration giving 50% inhibition (IC50) of PDGF binding was 0.5 microM for the most potent azo dye as compared with 10 microM for suramin. The azo dyes were generally more potent inhibitors of nonmitochondrial Ca2+ uptake and of inositol(1,4,5)trisphosphate-mediated Ca2+ release in permeabilized Swiss 3T3 cells than was suramin, and they were more potent inhibitors of PDGF-induced Ca2+ signaling in intact Swiss 3T3 cells. The azo dyes were only as effective as or less effective than suramin in inhibiting the growth of Swiss 3T3 cells, with IC50 values of between 74 and 361 microM being noted for the dyes as compared with 70 microM for suramin. The difference between the growth-inhibitory activity of the azo dyes and that of suramin could not be explained by metabolism of the compounds, which was not detectable in either Swiss 3T3 cells or human liver slice preparations. The results suggest that suramin and some of the azo dyes have actions on cell growth in addition to inhibition of growth factor binding and of Ca2+ signaling.


Evaluation of 9-dimethylaminomethyl-10-hydroxycamptothecin against xenografts derived from adult and childhood solid tumors.

The topoisomerase I inhibitor 9-dimethylaminomethyl-10-hydroxycamptothecin (topotecan) was evaluated against a panel of xenografts comprising four lines of adult colon adenocarcinoma, three colon tumors derived from adolescents, six childhood rhabdomyosarcomas from previously untreated patients as well as sublines selected in vivo for resistance to vincristine and melphalan, and three lines of childhood osteogenic sarcoma. Efficacy was determined at maximal tolerated dose levels using intermittent i.p. administration [every 4 days for 4 doses (q4dx4)] or daily p.o. or i.p. administration 5 days per week for up to 20 courses. On a q4dx4 schedule, the maximum tolerated dose (MTD) was 12.5 mg/kg per administration, which caused marked weight loss and lethality in approximately 5% of the tumor-bearing mice. This schedule caused significant growth inhibition (but no tumor regression) in advanced adult colon adenocarcinomas. The minimal treated/control (T/C) ratios were 0.49, 0.54, and 0.3 for three of the tumor lines and were achieved at 18-21 days after the initiation of treatment. In contrast, rhabdomyosarcomas were considerably more sensitive, with T/C ratios being < 0.1 for three lines, whereas topotecan was less active against two other rhabdomyosarcoma xenografts (minimal T/C ratios, 0.17 and 0.14). As inhibitors of topoisomerase I have been demonstrated to have activity in the replication phase of the cell cycle (S-phase-specific), prolonged administration schedules were examined. Mice received topotecan 5 days per week for 3 weeks either by i.p. injection or by oral gavage (p.o.). In selected experiments, p.o. administration was continued for up to 20 weeks. Oral administration for 3 weeks (2 mg/kg per dose) resulted in complete regression of all six lines of rhabdomyosarcoma, with two lines demonstrating no regrowth during the period of observation (> or = 84 days). Similar results were obtained after i.p. administration, suggesting significant schedule dependency for these tumors. For colon tumors, the daily administration schedule (i.p. or p.o.) demonstrated some advantage over the intermittent schedule, resulting in partial regressions and significant inhibition of the growth of several colon adenocarcinoma lines. In rhabdomyosarcoma Rh12 and VRC5 colon adenocarcinoma, both of which demonstrated intermediate sensitivity to topotecan, and in osteosarcoma OS33, protracted p.o. administration for 13-20 weeks (1.0-1.5 mg/kg per dose given daily x 5 days) caused complete regression without regrowth in Rh12 and OS33 tumors and partial regression of all VRC5 tumors. No toxicity was observed using this schedule of administration. Topotecan demonstrated significant activity against all three osteosarcoma xenografts examined, with optimal schedules causing complete regression in two lines.(ABSTRACT TRUNCATED AT 400 WORDS)


Choice of starting dose and escalation for phase I studies of antitumor agents.

The standard approaches to initial dose selection and dose escalation in phase I trials may be inappropriately conservative. These approaches mandate accrual of large numbers of patients, most of whom are treated at low and potentially ineffective doses. We compared the clinically determined maximum tolerable dose (MTD) with the starting dose of 45 drugs that had undergone phase I studies during the period 1977-1989. We also examined the number of dose-escalation steps required to achieve the MTD in relation to nonhematologic and hematologic dose-limiting toxicity. The median ratio of MTD to starting dose for all drugs was 20 (range, < 1-433) and the median number of dose levels studied to reach the MTD was 8 (range, 0-23). For drugs with nonhematologic dose-limiting toxicity, the median ratio of MTD to starting dose was 30 (range, 3-385) as compared with 12.8 (range, < 1-433) for those with hematologic dose-limiting toxicity (P = 0.023). The median number of dose-escalation steps required to reach the MTD was 9 (range, 2-18) for drugs with nonhematologic dose-limiting toxicity as compared with 5.5 (range, 0-23) for those with hematologic dose-limiting toxicity (P = 0.038). We also examined the response rate for 1,110 patients treated with 21 phase-I-study drugs for which response information was available. Responses were reported for 29 patients (2.6%). Among the 476 patients treated at the 3 highest dose steps, 17 responded (3.6%), which is double the response rate obtained at the lower doses (P = 0.08). It is suggested that although the usual methods for choosing starting doses and dose-escalation schemes for phase I studies are safe, they are overly conservative and delay opportunities for therapeutic benefit in phase I and subsequent phase II trials.


In vivo depletion of O6-alkylguanine-DNA-alkyltransferase in lymphocytes and melanoma of patients treated with CB 10-277, a new DTIC analogue.

There is increasing evidence to suggest that alkylation of guanine residues in DNA at the O6 position is the critical cytotoxic event following treatment with dacarbazine (DTIC) and related drugs and that endogenous O6-alkylguanine-DNA alkyltransferase (ATase) gene expression may be a major factor in resistance to such agents. 1-p-Carboxyl-3,3-dimethylphenyltriazene (CB10-277) was recently selected for clinical evaluation as a DTIC analogue with improved solubility, stability and (possibly) metabolic activation. Serial ATase levels were measured in peripheral blood lymphocytes of nine patients and in biopsied melanoma samples of two patients undergoing treatment with 24-h continuous infusion of CB10-277 (12 g/m2). Wide individual variations in pre-treatment levels as well as in the post-treatment depletion of lymphocyte ATase were seen. Progressive depletion of lymphocyte ATase was seen during continuous infusion of CB10-277 in all patients. Complete suppression of lymphocyte ATase activity occurred in two patients whose pre-treatment ATase levels were low. Immediately following completion of the CB10-277 infusion, the median ATase activity was 17% of pre-treatment levels (range, 0-67%). At 24 h after the end of the infusion, no recovery of lymphocyte ATase activity was observed in six patients, but significant recovery to 50%, 100% and 102% of pre-treatment activity occurred in the other three. In three patients who returned for subsequent cycles of chemotherapy at 4 weeks after the first dose, pre-treatment ATase levels showed a 3- to 4-fold increase relative to the original pre-treatment values. A significant correlation was found between the extent of ATase depletion and the initial lymphocyte ATase levels (r = 0.725, P < 0.05). Haematological toxicity developed in two patients and was associated with low pre-treatment ATase activity. Depletion of tumour ATase activity was noted in these patients, with residual activity amounting to 8% and 11% of pre-treatment levels, respectively, in the biopsies melanoma tissues. These results indicate extensive metabolism of CB10-277 to a methylating agent capable of mediating alkylation of DNA and subsequent depletion of lymphocyte and tumour ATase levels and further indicate that the effects on lymphocytes may reflect effects on the target tumour.


Pharmacokinetics and efficacy of rectal versus oral sustained-release morphine in cancer patients.

Sustained-release morphine (MST) given by the rectal route was compared with oral MST in an open randomised cross-over trial in ten patients with cancer who received stable doses of MST. No significant difference was found in the areas under the curve of the concentration-time profiles (AUC) following oral or rectal administration for parent morphine. The AUCs determined for morphine-6-glucuronide (M6G) and morphine-3-glucuronide (M3G) after oral administration were approximately twice those obtained following rectal administration. The maximal concentration achieved was lower and the time to maximal concentration was longer following rectal administration for morphine, M6G and M3G. The relative mean arrival times following rectal administration were significantly longer for morphine and M3G but not for M6G. These findings suggest slower absorption but less first-pass metabolism of MST after rectal administration. No significant difference was noted between the oral and the rectal route in measurements on visual-analogue scales for pain or side effects. We recommend the rectal route as being suitable for MST administration when the oral route is no longer available. In changing from oral to rectal administration, the same dose and dose interval may be used, but dose adjustment may be needed.


Tc-99m sestamibi myocardial imaging at rest for evaluation of cocaine-induced myocardial ischemia and infarction.

Many clinical cases of cocaine-induced myocardial infarction have been reported in the literature. Of the reported cases, patients tend to be young (in the third decade of life), chronic abusers with myocardial infarction typically involving the anterior left ventricular wall. This case report demonstrates the usefulness of two-phase (symptomatic and asymptomatic) Tc-99m sestamibi myocardial imaging at rest for definitive diagnosis of cocaine-induced myocardial ischemia and infarction.


Incidence and significance of enterogastric reflux during morphine-augmented cholescintigraphy.

One hundred fourteen patients with suspected acute cholecystitis underwent morphine-augmented cholescintigraphy. The 115 studies were reviewed first to determine the incidence of enterogastric reflux under these conditions. Overall, enterogastric reflux was observed in 85/115 (74%), occurring only after intravenous morphine sulfate in the majority (59%, 50/85). Noted prior to morphine in 41% (35/85), the degree of enterogastric reflux increased noticeably directly following drug administration in over half of these cases. Surgical diagnoses were established in 73/114 (64%) patients as follows: 56 (77%) acute cholecystitis, 15 (20%) chronic cholecystitis, and 2 (3%) another entity (normal gallbladder and tumor encasement). These pathologically proven cases were examined more closely to address the diagnostic significance of enterogastric reflux during morphine-augmented cholescintigraphy. Enterogastric reflux was demonstrated in the majority of not only those with acute cholecystitis (48/56, 86%), but also those with chronic cholecystitis (12/15, 80%). A frequent but nonspecific finding, enterogastric reflux appears to be a pathophysiologic phenomenon that may be enhanced synergistically, at least to some degree, in patients requiring morphine-augmented cholescintigraphy.


False-negative morphine-augmented cholescintigraphy in a patient with gangrenous cholecystitis.

Intravenous morphine sulfate is commonly used to shorten study time and has been reported not to lower the specificity of hepatobiliary imaging. Although the false-negative rate is low, caution has to be taken in interpreting morphine-enhanced cholescintigraphy. The report presents a false-negative study in a patient with acute gangrenous cholecystitis.


Morphine-augmented cholescintigraphy with a false-negative result and an apparent ectopic gallbladder.

Morphine-augmented cholescintigraphy has been shown to be a highly sensitive and specific means of evaluating acute cholecystitis. False-negative results do occur infrequently, however, and such a case is reported. In addition, this case initially demonstrated an apparent ectopic gallbladder, and thus anomalies in location of the gallbladder will be discussed.


Scintigraphic assessment of "effort" axillary-subclavian vein thrombosis.

"Effort" axillary-subclavian vein thrombosis (Paget-Schroetter syndrome) is an uncommon deep venous thrombosis due to repetitive activity of the upper limb. Clinical suspicion is usually confirmed by contrast venography. This report describes a case where the diagnosis was made by radionuclide venography (Tc-99m DTPA). The examination was carried out in the acute phase and clearly demonstrated the presence and the site of the obstruction as well as the collateral vessels. Despite a complete clinical recovery, obtained by medical therapy, further examinations performed in the follow-up period showed persistence of the thrombotic obstruction and a rich development of collateral vessels. In the authors' opinion, radionuclide venography is worth considering as a first-choice procedure when an axillary-subclavian vein thrombosis is suspected, and contrast venography should be performed only when surgical treatment is indicated.


Tc-99m HMPAO-labeled leukocytes for hematopoietic marrow imaging. Comparison with In-111 chloride.

The current study was initiated to define whether Tc-99m leukocyte imaging, compared to In-111 chloride imaging, could provide additional information on the hematopoietic activity of the bone marrow in diffuse hematologic disorders. A total of 11 patients with hematologic disorders were studied both with Tc-99m leukocytes and In-111 chloride. One patient with myelofibrosis showed disparate tracer distribution in the bone marrow between the two; Tc-99m leukocyte uptake in the central marrow was highly decreased, whereas In-111 chloride showed expanded marrow. The disparate results of granuloid hypoplasia and erythroid hyperplasia obtained by bone marrow biopsy and aspiration in this patient were thought to give an explanation for the radionuclide findings. The remaining 10 patients showed similar tracer distribution in the marrow, and the observation of hematopoietic cellularity confirmed by bone marrow biopsy and aspiration correlated well with the radionuclide findings. These results demonstrate that Tc-99m leukocytes may be a potential imaging agent for evaluating hematopoietic activity in the bone marrow, in particular granulopoietic activity.


Tc-99m DTPA diffuse pulmonary uptake in patients with coronary artery disease and renal insufficiency.

Diffuse bilateral lung uptake was observed in 10 patients undergoing Tc-99m DTPA renal scanning, referred for the evaluation of rising serum creatinine levels. All 10 patients demonstrated renal insufficiency (RI) as shown by both decreased bilateral renal tracer concentration and elevated background activity. Nine of the patients were known to have coronary artery disease (CAD) and six of these nine patients were in congestive heart failure (CHF), at or around the time of scanning. However, Tc-99m DTPA lung uptake was not observed in five other patients whose scans demonstrated RI, in whom there was no CAD or other cardiac disease. Diffuse lung uptake of Tc-99m DTPA in patients with RI therefore is highly suggestive of cardiac dysfunction (i.e. CAD and/or CHF).


Hepatic SPECT imaging in the detection and clinical assessment of hepatocellular disease.

A total of 95 patients, including 45 people with no evidence of liver disease and 50 documented hepatocellular disease patients, were studied to assess the value of planar and SPECT scintigraphy in the evaluation of hepatocellular disease. The accuracy and concordance between techniques was assessed using two criteria. Criterion 1, heterogeneity of the tracer in liver, yielded a concordance of 64%, whereas with criterion 2, liver and spleen tracer pattern, concordance was 78%. SPECT was significantly more accurate than planar imaging (P < 0.01), using both criteria. The clinical severity of the hepatocellular disease was further assessed in 72 of the patients and correlated with a liver scan severity rating scale. The SPECT technique showed a good correlation (r = 0.89) with the composite clinical severity score; however, no significant relationship with planar imaging was noted. The results of this study suggest that liver SPECT is a reliable technique for the assessment of hepatocellular disease.


Comparison of nomogram- and ultrasound-determined renal depths for calculation of glomerular filtration rates in spinal cord injury patients.

In an informal survey, poor correlation was found between 24-hour creatinine levels and glomerular filtration rates calculated from nuclear medicine studies in spinal cord injury patients. It was speculated that the discrepancies were because the nomograms used in the calculations did not take into account differences in body fat distribution for this patient group. Twenty-five chronic spinal cord injury patients were prospectively studied to compare glomerular filtration rates (GFR) using the nomograms based on height and weight and those using renal depth determined by ultrasound. It was found that the renal depth determined by nuclear medicine was significantly less than that determined sonographically. The mean difference between the total nuclear medicine-based GFR and total ultrasound-based GFR was 17.576 ml +/- 15.449 ml (P < or = 0.001). It was found that there was a significant difference between calculated GFRs based on renal depths as determined by the different methods. In addition, calculated GFRs based on ultrasound-determined depths corresponded more closely to 24-hour creatine clearance levels and with a smaller degree of error than those using renal depths determined by the nuclear medicine nomograms.


Primary malignant lymphoma of the central nervous system by Ga-67 and TI-201 brain SPECT.

Two patients with primary lymphoma of the central nervous system underwent both Ga-67 and TI-201 brain SPECT. Ga-67 scans showed remarkable accumulation of radiotracer corresponding to tumors detected by CT and MRI. More avid uptake was noted on the Ga-67 scans than on the TI-201 scans. In one patient, the intense tracer uptake had disappeared in the Ga-67 study performed after irradiation with 50 Gy. We are convinced that Ga-67 SPECT is useful for detecting and following the progress of primary lymphoma of the central nervous system.


Bone scan detection of pelvic metastasis from pleural mesothelioma.

The authors report a rare case of a symptomatic hematogenous osseous metastasis from a pleural mesothelioma. The lesion was initially detected by bone scintigraphy and was confirmed by MRI and subsequent open biopsy, despite a negative CT scan.


The sudden infant death syndrome: pathologic findings.

The last decade has witnessed a remarkable evolution in fundamental concepts regarding SIDS. It begins to appear now that the phenomenon is more likely the remote consequence of a subtle, physiologic birth defect than a single catastrophic incident. One can only hope that the next 10 years will continue to shed more light on this gradually resolving mystery.


Epidemiology of the sudden infant death syndrome: maternal, neonatal, and postneonatal risk factors.

Infants dying of sudden infant death syndrome (SIDS) constitute the single largest component of postneonatal infant mortality. Many different scientific approaches and hypotheses have been pursued in research studies over the past two decades. The field of epidemiology provides a comprehensive view of risk factors for SIDS with which theories of underlying physiologic defects or other putative causes should conform. Epidemiologic research has a vital role to play in assessing hypotheses derived from other types of studies.


Maturation of breathing.

In summary, although the basic mechanisms involved in the control of breathing during fetal and neonatal life are similar to those investigated more extensively in adult subjects, there are some aspects that make this control unique at this age. First, sleep seems to have a very profound effect during this period of life, particularly in the fetus, in which breathing is allowed to occur only during REM sleep. Second, in utero breathing activity is present since early gestation and without apparent reason, since it is not responsible for gas exchange. Being the lung of the fetus, the placenta is responsible for gas exchange. The purpose of fetal breathing must therefore be discovered. Third, the discovery of fetal breathing is probably the most exciting contribution made in this area during the last 50 years. To learn why this episodic breathing in utero becomes continuous after birth is the major challenge of the moment. Trying to understand this change at birth may result in the discovery of key mediators that are at the heart of the mechanism controlling breathing in general.


The cardiorespiratory control hypothesis for sudden infant death syndrome.

One or more abnormalities in cardiorespiratory control is the most compelling explanation for SIDS. Elucidation of the interrelationships between arousal responsiveness and gasping may be crucial to a better understanding of SIDS pathophysiology. The complex interactions need to be examined between arousal, autoresuscitation, and the other components of cardiorespiratory control. Prospective identification trials will be difficult since no cardiorespiratory control parameter yet identified has sufficient sensitivity and specificity, and trials assessing multiple parameters will be costly and cumbersome. Furthermore, prospective identification will be worthwhile only if an effective intervention has been established. To the extent that SIDS deaths still occur during documented monitoring, detailed analyses of the recorded cardiorespiratory events should finally provide us with objective data as to the terminal pathophysiologic events in SIDS victims and their relationship to aberrant cardiorespiratory control.


Neuromuscular control of upper airway patency.

To understand medical disorders such as obstructive apnea, or pulmonary aspiration, one must understand the many functions performed by the upper airway. These functions include respiration, airway protection at the face, feeding, and regulation of thoracoabdominal pressure. The neuromuscular mechanisms that perform these functions are complex. Many of the upper airway muscles can be classed as either airway constricting or airway dilating. These muscles regulate upper airway functions by regulating the shape of the upper airway.


Apnea of prematurity.

Apnea is a common, treatable disorder of respiration in premature infants, which usually resolves over time. The definition and classification of apnea are discussed, as well as its epidemiology and natural history. The pathophysiology of apnea is considered in detail, including the chemosensory and reflex input that modulates respiration and the involvement of upper airway control in the etiology of obstructive apnea. Finally, diagnosis and therapy are reviewed, and the relationship of apnea of prematurity to the underlying disorder in sudden infant death syndrome is considered.


Apparent life-threatening events and apnea of infancy.

This article is a critical review of the literature relating to the incidence, causes, pathophysiology, and therapy of apparent life-threatening events in infants. The clinical characteristics at the time of presentation and follow-up of infants who experience apparent life-threatening events are also summarized.


Siblings of sudden infant death syndrome victims.

The overall low recurrence rate of SIDS (< 2%) and the lack of concordance in twins are against SIDS being a genetic disorder. The most likely explanations for an increased incidence in siblings are that SIDS constitutes a mixed group of disorders that includes some genetic diseases and some disorders that are known to be recurrent but not genetic, and that some recurrences occur in families in whose lives there is severe deprivation, with many risk factors for SIDS, and in other families whose infant care practices, while not being overtly wrong, increase the risk of SIDS. With improving identification and management of these disorders and risk factors, it is expected that the incidence of SIDS, and, particularly, recurrent incidence in a family, will decrease. The best advice that can be given to families who have had an infant die from SIDS is that for most families the risk of another death from SIDS is very low (< 1%) and that if SIDS does recur, there will not be a prolonged period of suffering for the child. With this information and the recognition by most families that they do not regret having had the child who died, most families are prepared to welcome another pregnancy.


Prenatal substance abuse.

It has been reported that ISAM have an increased risk of SIDS and abnormalities of cardiorespiratory physiology. Abnormalities of cardiorespiratory control may account for the increased SIDS risk in some ISAM, and home monitoring is often used for ISAM with clinical apneic episodes. However, it is possible that the increased SIDS risk factors concentrated in this population. The increased SIDS risk SIDS risk factors concentrated in this population. The increased SIDS risk demonstrated in ISAM does not necessarily indicate that drug exposure during gestation in itself causes SIDS. Thus home monitoring is not indicated for ISAM who do not have apnea or other clinical evidence of a respiratory control abnormality.


Prospective identification of the risk of SIDS.

In the general population, there are a number of epidemiologic and physiologic factors that have been identified as increasing the risk for SIDS. To date, optimum combinations of these factors do not sufficiently discriminate the high-risk infant in order to serve as a basis for prospective screening. In the subsequently born sibling, the risk is only slightly increased, and, again, there are no factors that discriminate the infant at risk of death. Among infants who have sustained an ALTE, there are several identifiable causes or physiologic factors associated with high risk for a repeated event. This article has reviewed the association between risk factors and death in each of these three categories of patients.


Multichannel polysomnographic recording for evaluation of infant apnea.

The preceding discussion has consisted of a review of the technical and clinical aspects of pediatric multichannel recordings, which have become a widely used procedure in the clinical evaluation of infants with various apnea syndromes. It has been shown that multichannel recordings are superior to two-channel pneumocardiograms. Multichannel recordings should therefore be considered in all infants with unexplained episodes of apnea, bradycardia or cyanosis, in order to clarify the type of apnea and to rule out underlying conditions such as gastroesophageal reflux or seizures. The role of multichannel recording in predicting the risk of further apnea and SIDS, however, remains questionable. The clinical introduction of documented monitoring in the home setting with integrated pulse oximetry and a method for monitoring respiratory airflow might help to identify those infants at risk for apnea and SIDS in the future (see article by Weese-Mayer and Silvestri). Nevertheless, multichannel recordings in the hospital have provided a useful tool in the initial evaluation of many infants with infant apnea, and, for SIDS research, they have been useful for evaluating the complex autonomic control mechanisms during sleep and wakefulness.


Documented monitoring: an alarming turn of events.

Event recording of transthoracic impedance and electrocardiogram (documented monitoring) has recently become available to the clinician. Through its use, investigators have documented a remarkably low incidence of true alarms for apnea and bradycardia among monitored infants and children and an even lower incidence of clinically significant alarms. This technique has allowed clinicians to improve monitor management and to discontinue monitoring sooner. Coupled with recording of hemoglobin saturation and pulse waveform, this technology will serve to enhance our understanding of the pathophysiology of events that accompany apparent life-threatening events and that precede sudden infant death syndrome.


Home monitoring.

This article addresses the controversies surrounding home monitoring for the treatment of infant apnea and in the prevention of sudden infant death syndrome. A program for the use of monitoring is outlined for the practicing physician, and the benefits and deficiencies of home cardiorespiratory recording are discussed.


The counseling of SIDS parents.

The fundamental objectives in the management of sudden infant death syndrome (SIDS), as well as a brief historical review of SIDs with a description of the socioeconomic variables, are presented. The general patterns of reactions of parents of SIDS victims to the death of their child are discussed as is the role of the physician in counseling. Current problems, especially the relationship of SIDS to child abuse is discussed. A short list of major SIDS resource centers from which information and publications may be obtained is presented.


Computed tomography in blunt abdominal trauma: an analysis of clinical management and radiological findings.

We have retrospectively assessed the computed tomography (CT) findings in 92 patients suffering severe blunt abdominal trauma. Surgical findings and clinical follow-up were correlated with the CT findings. In nine patients CT was first used after emergency surgery and provided baseline data which was useful for further management. In two patients CT did not demonstrate small hepatic lacerations seen during previous surgery. No deaths were recorded. In 16 patients surgery followed CT within 24 h; there was good correlation between the CT and operative findings in 10 patients. However, CT failed to detect significant solid organ injury in five patients and was misleading (false positive) in another patient. There were two deaths amongst these 16 patients. Sixty-seven haemodynamically stable patients were initially managed non-operatively. Fifteen of these 67 patients had normal CT examinations; only one had subsequent laparotomy (for reasons unconnected with the trauma) where no injury was detected; there were no deaths. Of the 52 patients with an abnormal CT examination, 43 were successfully managed non-operatively. There were three deaths, including one where an injury missed at CT contributed to the demise of the patient. After an initial trial of non-operative management, the remaining six patients went to surgery where there was good concordance with the CT findings except for one missed renal injury. Active non-operative management of blunt abdominal trauma is widely accepted in haemodynamically stable patients and this report shows how CT supports this policy of surgical restraint in such cases. However, on review CT missed 13 injuries in nine patients overall; stricter attention to technique and better equipment may lead to improved results in the future.


Review of the use of MRI in soft tissue lesions.

The MR images of 34 patients with soft tissue lesions were retrospectively evaluated to assess the accuracy of the technique in distinguishing benign from malignant lesions, and to assess the usefulness of various criteria in making this distinction. The overall sensitivity for the detection of malignancy was 75% with a specificity of 94%. Size of lesion was found to be a good criterion in predicting malignancy, lesion margin and signal intensity were less useful. The tissue type was determined in a few instances where signal characteristics were typical, notably lipomas and neural tumours, but this was not reliable and in most lesions the tissue of origin cannot be determined on MR imaging and biopsy is necessary.


Prevertebral swelling in cervical spine injury: identification of ligament injury with magnetic resonance imaging.

In a retrospective analysis of 27 consecutive patients with acute cervical spine injury who underwent Magnetic Resonance (MR) Imaging, 14 had prevertebral soft tissue swelling on initial lateral radiographs, of whom 13 had anterior longitudinal ligament disruption on MR. Of the eight patients who had isolated prevertebral swelling in the absence of vertebral body fracture or significant subluxation, seven had anterior longitudinal ligament disruption shown on MR imaging. Of the patients with MR documented ligament injury, three had dynamic flexion-extension radiographs within 2 weeks of injury and all demonstrated cervical instability. As cervical prevertebral swelling following trauma was indicative of ligament injury in nearly half the patients, this finding should prompt clinical and radiographic follow-up to exclude spinal instability.


Fat-suppression magnetic resonance imaging in the preoperative localization of parathyroid adenomas.

Prospective localization of parathyroid adenomas was attempted in 16 patients with hyperparathyroidism prior to surgery. All patients had magnetic resonance imaging (MRI) using T1-weighted spin-echo (SE) sequences and a fat-suppression sequence, the short-tau inversion recovery (STIR) sequence. Correlation with the results of surgery yielded an overall sensitivity of 71% and a specificity of 94%. Performance was good in patients with previous surgery and with ectopic tumours. We believe that fat-suppression MRI is a valuable technique in the preoperative localization of parathyroid adenomas in patients with hyperparathyroidism.


Tarlov cysts--another cause of sacral insufficiency fractures?

Two cases of sacral insufficiency fractures occurring in patients with large Tarlov cysts are described. We suggest that Tarlov cysts and other bony defects in the sacrum may predispose to these fractures.


Delayed presentation of oesophageal perforation simulating intrathoracic malignancy.

We report two patients with silent oesophageal perforation. In neither patient was the diagnosis made preoperatively by the referring physicians and a history of swallowing difficulty was elicited in only one patient. The appearances on computed tomography were very similar in both patients: there was a soft tissue mass in the upper retro-oesophageal region with destruction of the underlying vertebral body.


Post-laparoscopic cholecystectomy bilomas--preliminary experience.

The incidence of biloma formation after laparoscopic cholecystectomy (LC) is, in the early experience of many centres, significantly higher than after open cholecystectomy. We describe four cases representative of the possible spectrum of post-LC bile leaks and review the literature regarding the radiologic investigation and management of this complication. We suggest that post-LC bilomas should initially be drained percutaneously. Endoscopic cholangiography (ERC) should then be used to identify the source of the leak, but sphincterotomy and/or stent placement may be best reserved for those whose leaks do not resolve after 10 days of free drainage. Surgery is recommended only for major biliary injury and for leaks that remain unresolved after sphincterotomy and/or stenting. An algorithmic summary of this approach is presented.


Ischaemic colitis: clinical, radiological and pathological correlation in three cases.

The clinical and plain radiographic findings in three patients presenting with ischaemic colitis are presented. The radiographic signs were atypical in that featureless dilatation of the large bowel was present with no evidence of gas within the bowel wall or 'thumbprinting', and changes were not localized to the left colon. No thrombotic or embolic vascular occlusion was evident on examination of the resected specimens. We attempt to correlate the pathological and radiological findings, and emphasize the importance of considering this diagnosis in elderly patients who have a dilated featureless colon on plain radiographs.


Dose reduction of hyoscine-N-butylbromide for double-contrast barium meal examinations--a prospective randomized study.

A search of the literature suggests that the conventional 20 mg dose of intravenous hyoscine-N-butylbromide (HBB) for smooth muscle relaxation in double-contrast barium meal (DCBM) studies is largely empirical. This study analysed the merits of three different doses (5 mg, 10 mg, 20 mg) in the performance of routine DCBMs. One hundred and twenty DCBM examinations were prospectively and randomly allocated to receive one of three doses. Three parameters were measured for each examination: gastroduodenal distension, delay in gastric emptying and gastric antrum overlapping with barium-filled duodenal loops. Almost half the examinations using 5 mg produced undesirable duodenal-gastric overlay. Unacceptable early flooding of the duodenal bulb with barium was seen mostly with doses of 5 mg and 10 mg. Overall, the best results were obtained with 20 mg. The continued use of 20 mg HBB in routine DCBMs is recommended.


Observer variability in the sonographic measurement of renal length in childhood.

The intra- and interobserver variability of the measurement of renal length in an unselected series of children attending for renal tract ultrasound were estimated using a standard technique and test-retest protocol. The standard errors of measurement were calculated and the limits of agreement derived. The results indicate that for normal kidneys there is a 95% probability that a second measurement by one observer will be within 4.6 mm of his first reading. Similarly, a single measurement will be within 7.8 mm of a reading by a second examiner. For abnormal kidneys in this series the intraobserver variability was similar to normal kidneys but interobserver variability was greater. Observer error in the measurement of renal length is equivalent to between 2 and 3 years normal growth for children older than 1 year.


Case report: renal excretion of gastrografin following rectal administration.

Renal excretion of water soluble iodinated contrast media following oral administration has often been described but no reports describing renal excretion following rectal administration of such contrast have previously been described. We describe a case of renal excretion of diatrizoate methylglucamine (Gastrografin, Schering) following a diagnostic 'gastrografin enema' in a woman with caecal carcinoma.


Case report: lymphoma causing small bowel intussusception in a patient with the acquired immune deficiency syndrome.

We present the case of a patient with the acquired immune deficiency syndrome (AIDS) who developed an ileo-ileal intussusception due to lymphoma of the small bowel. The clinical and radiographic findings are described.


Case report: metastatic transitional cell carcinoma presenting in a urinoma.

We describe a case of transitional cell carcinoma (TCC) metastasising into a urinoma cavity in a patient where the primary tumour arose at the ipsilateral ureterovesical junction. Seeding of transitional cell carcinoma into contiguous structures following surgical intervention has been reported, but to our knowledge, this is the first report of spread into a distant urinoma.


Case report: intra-ureteric metastasis from testicular teratoma.

The case report of a patient found to have intra-ureteric metastatic teratoma is presented. This has not to our knowledge previously been reported in the literature.


Case report: metallic mercury embolism--deliberate self-injection.

The first ever report of self-administration of mercury via both arterial and venous routes is presented. The unique feature of this case is the accidental self-injection of mercury into the ulnar artery.


Case report: desmoplastic fibroma of the sternum.

Desmoplastic fibroma of bone is very rare. This is only the second case reported in the sternum and the first reported with CT findings.


Paroxetine, sertraline, and fluvoxamine: new selective serotonin reuptake inhibitors.

The pharmacology and pharmacokinetics, adverse effects, drug interactions, efficacy, and dosage and administration of the new selective serotonin reuptake inhibitors paroxetine, sertraline, and fluvoxamine are reviewed. Paroxetine, sertraline, and fluvoxamine all have large volumes of distribution and are highly bound to plasma proteins. In contrast to fluoxetine, these three drugs possess shorter elimination half-lives of approximately one day and are metabolized to clinically inactive compounds. Nausea was the most commonly reported adverse effect for all three agents. Other reported adverse effects are headache, sedation, dry mouth, insomnia, sexual dysfunction, and constipation. Because of their favorable pharmacokinetic profiles, paroxetine, sertraline, and fluvoxaetine are less likely than fluoxamine to interact with other drugs. Paroxetine has been found to be superior to placebo and equivalent to amitriptyline, imipramine, clomipramine, and doxepin in treatment of depression. Sertraline has been found to be superior to placebo and equivalent to amitriptyline in treatment of depression. Fluvoxamine has been found to be superior to placebo and equivalent to imipramine, clomipramine, desipramine, mianserin, and maprotiline in the treatment of depression. Fluvoxamine and sertraline have been shown to be superior to placebo in the treatment of obsessive-compulsive disorder. Clinical experience has demonstrated all three drugs to be effective in treatment of depression. They may be especially useful in elderly patients, in those who cannot tolerate alternative treatments, and in those who do not respond to adequate trials of other antidepressant therapies.


University of North Carolina Caries Risk Assessment Study: comparisons of high risk prediction, any risk prediction, and any risk etiologic models.

The purpose of this analysis is to compare three different statistical models for predicting children likely to be at risk of developing dental caries over a 3-yr period. Data are based on 4117 children who participated in the University of North Carolina Caries Risk Assessment Study, a longitudinal study conducted in the Aiken, South Carolina, and Portland, Maine areas. The three models differed with respect to either the types of variables included or the definition of disease outcome. The two "Prediction" models included both risk factor variables thought to cause dental caries and indicator variables that are associated with dental caries, but are not thought to be causal for the disease. The "Etiologic" model included only etiologic factors as variables. A dichotomous outcome measure--none or any 3-yr increment, was used in the "Any Risk Etiologic model" and the "Any Risk Prediction Model". Another outcome, based on a gradient measure of disease, was used in the "High Risk Prediction Model". The variables that are significant in these models vary across grades and sites, but are more consistent among the Etiologic model than the Predictor models. However, among the three sets of models, the Any Risk Prediction Models have the highest sensitivity and positive predictive values, whereas the High Risk Prediction Models have the highest specificity and negative predictive values. Considerations in determining model preference are discussed.


Correction of self-assessment of dental conditions.

A correction matrix for self-assessed data on dental conditions was developed. 100 subjects, who were randomly selected among 2383 respondents to a questionnaire, were clinically examined. The dental conditions, determined clinically and through self-assessment, were recoded to seven dental categories, and the agreement between the two methods of reporting were investigated. For persons with prosthodontic work and/or edentulous persons the self-assessment was valid, whereas people with remaining teeth overreported their dental conditions through self-assessment. The overreporting did not depend on gender, but was dependent on age, which again was related to dental status. The overreporting was most marked for persons having one to two single teeth or several single teeth missing and not replaced.


Comparative effectiveness of visual/tactile and simplified screening examinations in caries risk assessment.

Central to the development of a model for identifying children at high risk to caries is a clinical evaluation to assess dental status and other conditions potentially useful in caries prediction. Traditionally, this evaluation has been based on a relatively lengthy visual/tactile examination conducted by a dentist. Replacing the dentist examination with a dental auxiliary conducted screening evaluation could lead to reduced time and costs. The 4-yr University of North Carolina Caries Risk Assessment Study involved approximately 5000 schoolchildren initially in Grades 1 and 5 living near Aiken, South Carolina, and Portland, Maine. The effectiveness of caries prediction models using visual/tactile examination data were compared with the same models using simplified screening evaluation data. Results showed sensitivity ranged from 0.57 to 0.61 for the visual/tactile and screening models by site and grade cohort. Specificity for the models ranged from 0.80 to 0.83. None of these differences in sensitivity and specificity between visual/tactile (dentist) and screening (hygienist) models was statistically significant. Findings show that for the prediction of children at high risk to dental caries the clinical evaluation may be conducted with no reduction of precision by using dental hygienist performed screening evaluations rather than dentist conducted visual/tactile examinations. While no cost data were collected, these results imply that costs to future prediction programs could be reduced by using screening evaluations.


Intrinsic motivation in dental care.

The aim of this work was to develop a method based on the idea of intrinsic motivation for analyzing motivation problems in dental care. A questionnaire dealing with intrinsic motivation was filled in by 207 women and 183 men. Factor analysis of the scale revealed the following dimensions of internal-external motivation: independence, responsibility, vs. non-independence, interest in preserving one's own teeth as long as possible vs. preference for tooth extraction, satisfaction from brushing teeth vs. brushing for others' sake, and critical evaluation of diet vs. improper diet with carbohydrates. The reliability of the questionnaire was good (standardized item alpha .69). The individual's own sense of independence and responsibility and the idea of preserving one's own teeth for as long as possible were found to be more important for the women than for the men. A longer education was also found to be related to preserving one's own teeth as long as possible. The time of the last dental visit was positively related to independence, responsibility and the far-reaching idea of preserving one's own teeth. It can be concluded that aspects of intrinsic motivation can give additional information when trying to understand dental health behavior.


Dental caries and its determinants among recent immigrants from rural Ethiopia.

Adults (35-45 yr old) and children (5 and 12 yr old) recently arrived in Israel from rural areas in Ethiopia were examined. Caries levels were low: e.g. DMFT = 0.31 among 12-yr-olds, and 1.27 amongst adults. The 5-yr-olds were 86.8% caries-free, while 12-yr-olds were 81.8% and adults 54% caries-free respectively. According to interview data, the diet in Ethiopia had been based on local agricultural products and was almost sugar-free. The mean total count of salivary bacteria, as determined on blood agar, was 3.4 x 10(8); mean count of Streptococcus viridans, on mitis salivarius, was 6.7 x 10(7); and mean count of S. mutans, as determined on mitis salivarius with bacitracin, was 1.7 x 10(7). These levels were all high and were not significantly different from a control group of 20 Israelis. The mean number of lactobacilli, on Rogosa agar, was 2.75 x 10(4), which was significantly higher than among the controls (3.6 x 10(3). Salivary pH levels were generally similar between the Ethiopian group and the controls. Salivary flow was significantly higher for the Ethiopians (1.93 ml/min) than for controls (1.16 ml/min). Low levels of caries in this population can be attributed to an almost sugar-free diet and high salivary flow, but not to the composition of oral microflora.


Dental caries, sugar consumption and restorative dental care in 12-13-year-old children in Riyadh, Saudi Arabia.

A 3-day dietary history was obtained from 363 Riyadh schoolchildren aged 12-13 yr, after which their dentitions were examined for dental caries. About 16-31% of the children were caries-free and the mean DMFT varied between 1.67 and 2.43. However, in those with at least one tooth decayed, missing or filled, the mean DMFT remained constant at about 3, irrespective of age or gender; and most of the carious teeth were unrestored. There was a statistically significant relationship between DFS and the frequency of sugar consumption on the first 2 days of the dietary diary. It is suggested that the management of dental caries in the children must include the control of dietary sugar.


Development of a Dutch version of the Dental Visit Satisfaction Scale.

A Dutch version of the Dental Visit Satisfaction Scale has been developed. The DVSS consists of 10 items, measuring three aspects of patient satisfaction with the dentist. Item and scale characteristics of the Dutch version and the English version compared rather well. Likewise, the factor structure of the Dutch and the English version of the DVSS was very similar. A suggestion for modification of the DVSS was made.


Comparative study of oral health status between Scottish and Japanese schoolchildren aged 6-11 years.

This study was carried out to examine and compare the differences in oral health status between Scottish (Fife) and Japanese (Motoyoshi) primary schoolchildren, and also to analyse some factors concerned with the differences found. It was observed that caries experience is higher in Motoyoshi than in Fife, despite Fife schoolchildren having poorer oral cleanliness and consuming snacks more frequently. However, Fife children had more fissure sealants and brushed their teeth more frequently with fluoridated dentifrice than did Motoyoshi children. The sugar content of snacks consumed by Motoyoshi children was higher than that of the Scots. Gingivitis (PMA positive rate) was higher in Fife than in Motoyoshi, and it was also noted that Fife children were less independent than Motoyoshi children in their daily behaviour.


Caries prevalence among adults in communities with optimal and low water fluoride concentrations.

The aim of this study was to compare the dental health status of adults measured as caries prevalence in two socioeconomically similar communities with optimal and low water fluoride concentrations respectively. Other topical fluoride sources are also taken into consideration. The study is based on clinical and radiological examinations of 30-40-yr-old subjects who for all their lives have been drinking water with a fluoride concentration representative for the community. 260 individuals resident in the optimal fluoride area and 236 from the low fluoride are included in the study. The results show that caries prevalence was lower in the optimal fluoride area. Caries prevalence was higher in women than in men within both groups. The prevalence of primary caries was low but significantly higher in the low fluoride area, principally in the form of proximal caries. Caries prevalence was not influenced by other topical fluoride sources.


Determining optimal levels of fluoride in drinking water for hot, dry climates--a case study in Sri Lanka.

The prevalence of dental caries and dental fluorosis was examined in 380 14-yr-old children living in four geographic areas of Sri Lanka with water F-levels of 0.09-8.0 ppm. A reduction in caries prevalence by 43% was recorded in children consuming 0.6-0.79 ppm F- compared to those in low fluoride areas (< 0.4 ppm). Among those consuming drinking water containing < 1.0 ppm F-, however, 32% of the children had mild forms and 9% severe forms of dental fluorosis (Dean's index). Although other sources of F- may contribute to this effect, the prevalence and severity of dental fluorosis seen in low fluoride areas was confirmed to be high in rural Sri Lanka. Our data are comparable with recent findings from other tropical countries, e.g. Kenya and Senegal, and reaffirm that WHO guidelines for the upper limit of F- in drinking water may be unsuitable for developing countries with a hot, dry climate. Current knowledge now enables us to recommend 0.8 ppm as an appropriate upper limit for F- in drinking water supplies for these populations.


Dental caries experience and prevalence of children afraid of dental treatment.

The aim of this study was to examine the clinical outcome with regard to dental caries of high self reported dental anxiety in a group of Scottish secondary schoolchildren. 1103 children participated in the study, mean age 14 yr (sd 0.35 yr), and the prevalence of high dental anxiety was 7.1% (95% CI = 5.6%, 8.6%). When these children were compared with their contemporaries their DMFT and all its components were higher but only the mean MT reached statistical significance after adjusting for gender and social class. Children with a high dental anxiety were 62% more likely to have at least 1 missing tooth due to caries. In addition this group when compared to the rest of the study population, had a significantly lower mean number of teeth fissure sealed and a lower proportion of children with sealants. No similar trend was obvious for children who had a high general fear. The dentally anxious more accurately perceived their treatment need and were more likely to defer, cancel or not turn up for dental appointments.