Approaches to evaluating the toxicity and carcinogenicity of man-made fibers: summary of a workshop held November 11-13, 1991, Durham, North Carolina.

The Workshop on Approaches to Evaluating the Toxicity and Carcinogenicity of Man-Made Fibers (MMF) was held in Durham, North Carolina, on November 11-13, 1991. The goal of the workshop was to reach a consensus, or to determine the extent to which a consensus existed, in two areas. Participants were asked to identify scientifically sound approaches for evaluating the toxicity and carcinogenicity of man-made fibers based on today's science and to determine research appropriate for study during the next 5 years that can provide an improved scientific basis for future revisions of approaches used to evaluate man-made fiber toxicity and carcinogenicity. During the first day, a series of "state of knowledge" presentations were made to provide all participants with a common data base from which to interact and discuss scientific issues. The workshop participants were assigned to one of four discussion groups, which met separately in three half-day sessions following the first day of presentations. All groups discussed the same topics: exposure assessment, hazard identification, and dose-response information needed to integrate to characterize risk in the first session; approaches to obtaining the needed information in the second session; and recommended approaches and guidelines for evaluating the toxicity and carcinogenicity of MMF and research needs in the third session. The workshop participants reconvened as a whole after each discussion session, and one member from each group reported the group's conclusions. A closure period was also included at the end of the workshop for review and discussion of items that had been considered during the workshop. The primary conclusions reached were the following: -All fiber types capable of depositing in the thorax are not alike in their pathogenic potential. -Only fiber samples with dimensions similar to those to which humans can inhale should be tested. -A complete characterization (i.e., dimensions, fiber number, mass, and aerodynamic diameter) of the fiber aerosol and retained dose is essential. -Appropriate aerosol generation methods must be used for inhalation studies in order to preserve fiber lengths. -A tiered approach to toxicity evaluation is recommended that includes: 1. In vitro screening for durability, surface properties, cytotoxicity, and similar properties, etc; 2. Short-term inhalation or other in vivo studies; 3. That chronic inhalation studies are the "gold standard" (i.e., provide most appropriate data for risk characterization). -The rat is the most appropriate species for inhalation studies. -In chronic inhalation studies, animals should be retained to at least 20% survival after 2-year exposure. -Serial lung burden analyses are an essential component of inhalation studies and are essential for understanding exposure-dose-response relationships. -Studies oriented to understanding mechanisms of toxicity and carcinogenicity are important adjuncts to traditional toxicity studies. -Histopathological analyses of tissues of the respiratory tract represent primary endpoints for evaluating effects of inhaled fibers. Major effects include pulmonary fibrosis, lung tumors, and mesotheliomas. Experimental tissues should be archived for future studies; wherever possible, handling and preservation of tissues should be done in a way that maximizes their future use in mechanistic studies. -Potential human exposures throughout the entire life-cycle of the fiber must be considered and fibrous material for toxicologic studies prepared accordingly. -Intracavity studies are inappropriate for risk characterization but can play a useful screening role in assessing fiber toxicity.(ABSTRACT TRUNCATED AT 400 WORDS)


[Utility of premedication with different regimens of omeprazole and ranitidine in the prevention of acid broncho-aspiration syndrome].

To study the usefulness of several omeprazole regimens on gastric fluid volume and pH in patients undergoing elective surgery. We analyzed 105 patients undergoing to elective surgery who received prophylactic treatment for the acid aspiration syndrome. They were randomly allocated into 7 homogeneous groups according to the therapeutic regime. Placebo (group 1), oral omeprazole (20 mg) the night prior to surgery (group 2), oral ranitidine (150 mg) the night before (group 6), two doses (the previous night and before surgery) in the remaining three groups: 20 mg of omeprazole (group 4), 40 mg of omeprazole (group 5) or 150 mg of ranitidine (group 7). In all patients we measured pH and volume of the gastric content after induction of anesthesia and one hour thereafter. There were no statistically significant differences in mean pH values and gastric volume content among groups 1.2,3, and 6 (2.1 (pH) and 27 ml (gastric volume) in group 1, 2.1 and 23 ml in group 2, 2.6 and 19 ml in group 3, and 2.2 and 32 ml in group 6). With repeated doses of 40 mg omeprazol (group 5), mean pH values were comparable to those found with the two doses of ranitidine (4.1 +/- 1.8 vs 4.1 +/- 3.6) although gastric volumes were significantly less (12 +/- 2.6 ml vs 20 +/- 4.8 ml). These two groups showed significantly greater mean pH values and less gastric volumes than the remaining patients. The incidence of patients with gastric content deemed at risk for acid aspiration (pH less than 2.5 and gastric volume greater than 25 ml) was less after premedication with two oral doses of omeprazole (40 mg) than either two doses of ranitidine (150 mg) or smaller doses of both drugs.


[Chronotropic changes and cardiac arrhythmias during anesthetic induction and intubation in patients undergoing heart surgery. Study of 79 patients using Holter monitoring].

To assess changes in heart rate and cardiac arrhythmias during anaesthetic induction and tracheal intubation in patients undergoing cardiac surgery. 79 patients scheduled for cardiac surgery were divided into three groups: group I, 36 valvular diseases with a good ventricular function, group II, 22 valvular diseases with an ejection fraction less than 0.5, and group III, included 21 patients with coronary artery disease. All patients had a Holter monitoring. Anesthesia was performed with diazepam and morphine in patients with valvular disease and with diazepam and fentanyl in those with coronary artery disease. During anesthesia induction there were no significant increases in heart rate in the two groups of patients with valvular diseases: in group I (n = 36, with good ventricular function) heart rate increased by about 5.4 +/- 23% and in group II (n = 22, with ejection fraction less than 0.5) by 7.5 +/- 33%. In patients with coronary artery disease (n = 21) we did not observe significant decreases in heart rate (-4.28 +/- 17%). During tracheal intubation the heart rate increased by 15.9 +/- 30% in group I (p < 0.002), by 13.6 +/- 30% in group II (p < 0.02), but decreased by 1.19 +/- 23% (p = NS) in patients with coronary artery disease. During anesthetic induction we observed frequent premature beats (single forms) in 13.8% of patients in group I, 13.6% in group II, and 9.5% in group III. The incidence of this arrhythmia during tracheal intubation was 16.6%, 9%, and 14%, respectively for the three groups. Sustained ventricular tachycardia was only observed in one patient. Changes in heart rate and ventricular arrhythmias occurring during anesthetic induction and tracheal intubation in patients undergoing valvular and coronary surgery were infrequent and not severe.


[Design of an expert system for decision-making in an emergency situation].

To study the clinical applicability of the expert system URGSANT as a help in making up decisions in emergencies. URGSANT is an expert system implemented in INSIGT 2+ which is structured in a modular and hierarchical form. It contemplates 44 urgent situations relating to the central nervous system, hematopoietic, cardiovascular, respiratory, gastrointestinal, genitourinary, endocrinological, and miscellaneous group. Validation of the program was made by four anesthesiologists who evaluated the performance of the program in 25 emergency cases and in 25 other situations that were treated by other specialists. The rationale of the system was basically correct. In most cases the program was considered efficient or very efficient during the different clinical situations and only in one case its guidance was wrong. The URGSANT expert system is an efficient and useful method for the clinician during emergency situations.


[Indications for the use of platelets, plasma and anti-hemorrhagic drugs].

During the last years, the use of hemoderivatives has largely increased. Their use carries a high risk for post-transfusion reactions and for transmission of severe infectious diseases. In a high percentage of cases the use of these compounds is inadequate. At the present time there are pharmacologic (desmopressin, antifibrinolytics, vitamin K) and nonpharmacologic strategies (autotransfusion, hemodilution, intra and postoperative recovery of blood) directed to avoid or to decrease the need for transfusion. We review all these strategies and we propose some criteria for transfusion of plasma and platelets, as well as attitudes for particular situations.


[Approach to the scientific work of Jaume Raventós (1905-1982)].

We analyze the scientific work done by Jaume Raventós (1905-1982) preceded by a brief biographic profile. The work of this Catalonian investigator has been separated into two stages: The first one, called the Barcelona period, is the training phase and comprises three moments: during the first one (1925-1927) the scientific participation of Raventós is still marginal; during the second period (1928-1933) he began to collaborate in large projects with A. Pi Sunyer and F. Doménech Alsina; and during the third period (1932-1934) he developed its own experimental line that culminated with his Doctoral Thesis. The second stage, called the British period, includes all work done during his exile at the United Kingdom. This phase can also be divided into three periods: the first one (1936-1939) took place in Edinburgh and was characterized by a continuation of the scientific line initiated in Barcelona; the second period developed in Manchester (1939-1954) and includes the studies with intravenous barbiturates; the third period (1956-1965) encompasses the last years of Raventós investigative activity which was devoted to the study of fluothane a new volatile anesthetic agent.


[Radial nerve injury caused by external compression during the dissection of the internal mammary artery in coronary surgery].

Injury of the radial nerve produced by external compression during dissection of the internal mammary artery during surgery of ischemic heart disease, is an infrequent event. The use of sternal retractors with only one rod may be the cause of these lesions. We report two cases of radial nerve paralysis produced as a consequence of external compression induced by a sternal retractor during dissection of the internal mammary artery. In the first case the patient showed loss of power of the external muscles of the left forearm and a clear flexion of the left hand. The second patient presented loss of power of the left hand and impossibility to extend the carpus and fingers. In both cases the lesion was reversible.


[Inhalation anesthesia in porphyria variegata].

We report the anesthetic technique performed in a 38 year old woman with variegate porphyria who underwent a partial right mastectomy. The patient was diagnosed in 1984 on the basis of the biochemical profile and enzymatic deficit. She presented marked photosensitivity without neurological or systemic symptoms. Among their personal antecedents an uneventful general anesthesia in 1982 was recorded. The patient was premedicated one hour before surgery with 0.25 mg of scopolamine, 5 mg of dihydrobenzperidol (DHB), and 100 micrograms of fentanyl, all of them given by the intramuscular route. At the operating theater the patient received 5 mg of diazepam, 2.5 mg of DHB, and 200 micrograms of fentanyl. Anesthetic induction was done with a bolus of 20 mg of etomidate, 1 mg of atropine, and 60 mg of suxamethonium. Maintenance of the anesthetic level was achieved with 0(2), N2(0) with 0.5 of 1% isoflurane, and 40 mg of atracurium in two doses. Surgery lasted 50 min and pharmacologic reversion of the anesthesia was not required. Urine was collected in a dark recipient 24 hours after surgery in order to measure the following parameters: porphobilinogen, aminolevulinic acid, coproporphyrins and uroporphyrins. We found a significant increase of uroporphyrins at the three sampling times, although this increase was less marked during surgery, probably due to hemodilution. We stress the advantages of inhalation anesthesia in these patients.


[Paradoxical reaction to midazolam after its use as a sedative in regional anesthesia].

We report 3 cases of paradoxical reaction to midazolam after being used for sedation during regional anesthesia. The picture was characterized by a marked aggressiveness. In one case the reaction was treated with general anesthesia, whereas in the other two patients the clinical picture was rapidly reversed by administration of flumazenil. We describe the possible causative mechanisms of this reaction as well as their treatment.


Statistical handling of drop-outs in longitudinal clinical trials.

This paper considers the statistical complexities that arise due to outcome related drop-outs in longitudinal clinical trials of the randomized parallel groups design with fixed assessment times and an explanatory aim. The shortcomings of currently popular methods of coping with the problem of drop-outs are discussed. It is proposed that progress can be made by applying the modern methodology that was primarily developed for sample surveys with non-response and for observational studies. A practical application using the Hamilton Rating Scale for Depression is presented.


Using toxicity grades in the design and analysis of cancer phase I clinical trials.

Ethical considerations in a cancer phase I trial require a design allowing determination of the maximum tolerated dose with a minimum number of patients treated at low ineffectual or high overly toxic doses. It would also be advantageous to complete the phase I trial in as short a period of time and with as few patients as possible to allow further resources for later studies in which patients are treated at the optimal dose. Several dose escalation schemes are compared. These are the Fibonacci, two two-stage schemes, and a proposed scheme which uses knowledge of all toxicity grades. Estimates of the maximum tolerated dose are obtained and compared using the dose escalation schemes alone, a logit model, and a proposed mean response model. Confidence intervals using the delta method are obtained from the logit and mean response models. The proposed scheme and the two-stage schemes have the advantage of requiring fewer patients, particularly at low doses. Confidence intervals obtained from the mean response model have better coverage than those from the logit model. Data from a cancer phase I trial of dipyridamole and acivicin is presented to illustrate the methods.


Importance of trends in the interpretation of an overall odds ratio in the meta-analysis of clinical trials.

This paper contains a proposition related to the publication of meta-analyses of clinical trials. We consider the situation where the results of a number of trials are summarized by a common or typical odds ratio. We show that stating such an odds ratio as the summary of evidence from a number of trials can be misleading if certain systematic differences between trials exist. In such cases the author should state not just one odds ratio but also its dependence on the relevant characteristics of the trials. In particular, we propose that those reporting a meta-analysis state in advance a (limited) number of variables to be considered for potential interaction with the exposure (risk factor or treatment) of interest. The list might include centre size and the odds in the placebo or control group if such an effect is a priori clinically plausible. The trials should be ordered according to each of these variables and a trend test for the odds ratio should be computed. Apart from a 'genuine' effect, an appreciable interaction could also be indicative of the (multiplicative) odds ratio being an inappropriate measure for the particular meta-analysis. Without any consideration as to the possibility of interaction, the meta-analysis should be considered incomplete. If such an interaction exists, the odds ratio should be stated as a function of the interacting variable, either as a formula or (preferably) in a table stating the odds ratio for a number of different values of the interacting variable, and not as a single summary statistic.


Comparison of adjusted attributable risk estimators.

The estimation of attributable risk in the presence of confounding and effect modification is studied in this paper. Different adjustment methods for the attributable risk are reviewed. The results of a stimulation study comparing these methods under the unrestricted multinomial sampling model are reported. From the study it is concluded that the maximum likelihood estimator resulting from the 'case load weighting' of the stratum-specific attributable risk estimates will be the best overall choice in all practical situations with relatively large sample sizes. Other adjusted attributable risk estimators depend heavily on the underlying structure of the multinomial model.


A bootstrap resampling procedure for model building: application to the Cox regression model.

A common problem in the statistical analysis of clinical studies is the selection of those variables in the framework of a regression model which might influence the outcome variable. Stepwise methods have been available for a long time, but as with many other possible strategies, there is a lot of criticism of their use. Investigations of the stability of a selected model are often called for, but usually are not carried out in a systematic way. Since analytical approaches are extremely difficult, data-dependent methods might be an useful alternative. Based on a bootstrap resampling procedure, Chen and George investigated the stability of a stepwise selection procedure in the framework of the Cox proportional hazard regression model. We extend their proposal and develop a bootstrap-model selection procedure, combining the bootstrap method with existing selection techniques such as stepwise methods. We illustrate the proposed strategy in the process of model building by using data from two cancer clinical trials featuring two different situations commonly arising in clinical research. In a brain tumour study the adjustment for covariates in an overall treatment comparison is of primary interest calling for the selection of even 'mild' effects. In a prostate cancer study we concentrate on the analysis of treatment-covariate interactions demanding that only 'strong' effects should be selected. Both variants of the strategy will be demonstrated analysing the clinical trials with a Cox model, but they can be applied in other types of regression with obvious and straightforward modifications.


A latent class model for repeated measurements experiments.

Standard models for the analysis of repeated measurements assume a common response profile for all experimental units within a treatment group. However, in many applications this under-represents the nature of the response. There may be several distinct modes of response within a group (for example, responders versus non-responders to a given treatment), or there may be a set of distinct response profiles which are common to all the treatment groups. In these situations the effect of treatment can be characterized both by the shape of the fitted profiles and by estimating the proportion of cases who exhibit each particular response profile. This paper describes how such experiments may be analysed through the introduction of a latent variable into the standard model. Maximum likelihood estimation is straight-forward using the EM algorithm. Model choice requires some care, but good-fitting models can be identified via inspection of residuals and the use of empirical semi-variogram plots. Once the number of distinct profiles has been determined, treatment effects can be investigated using likelihood-ratio statistics. The approach is illustrated with a re-analysis of a dataset first described by Grizzle and Allen.


Analysis of factors influencing the efficacy of pooled platelet transfusions.

The results of 839 platelet transfusions in 115 patients were studied to establish the relative importance of 10 clinical factors in determining the efficacy of pooled donor transfusions. Efficacy was measured by the one hour corrected increment in platelet count. The number of transfusions available for study from individual patients varied widely from 1 to 37. Two methods of analysis are presented. The first makes assumptions about the correlation between transfusions within patients, and the variation between patients. The second is based on a repeated sampling procedure whereby unbiased estimates of the parameters of interest are obtained from random samples containing only one transfusion per patient.


Identification of pulses in hormone time series using outlier detection methods.

The identification of discrete hormonal secretory pulses is of critical importance in clinical endocrinology. Pulses are defined as sudden increases in hormone concentration followed by exponential decay. We propose a model-based iterative procedure for pulse detection in pulsatile hormone time series. Our model is seen to be analogous to the model for innovation outliers in autoregressive series, and outlier detection techniques for pulse identification are adapted to the endocrine context. An original feature of the procedure is that it distinguishes between true pulses and gross observation outliers in the series. Simulation experiments are used to investigate the behaviour of the method under physiologically or clinically relevant circumstances. Five experimental endocrine series from rhesus monkeys, where the times of the pulses are known from the concomitant recording of the electrical activity of the hypothalamus, are analysed.


24-hour blood pressure measurement in antihypertensive drug trials: data requirements and methods of analysis.

Non-invasive ambulatory blood pressure monitoring is an appropriate technique for the identification of the target population requiring antihypertensive treatment, since the systematic bias seen in casual clinic measurement is removed. The use of the technique in controlled clinical trials leads to a reduction in the sample size required to show a treatment difference in antihypertensive effect compared to sporadic single measurements, although in practice the number of recruited patients can considerably exceed the number of evaluable patients, due to poor compliance or incompleteness of data. In addition, the equality of observation essential in clinical trials cannot be controlled to the same degree as is possible with clinic measurements. Comparison of estimators of the overall characteristic blood pressure reveals that the 24-hour mean value produces an adequate estimator. A description of the individual blood pressure profile is obtained using smoothing procedures, the moving interval average providing a robust and simple approach. Clinically meaningful characteristics of the profile are difficult to define due to a dearth of information on prognostic importance of the features of the 24-hour blood pressure profile. Smoothed individual profiles can be combined to produce graphical descriptive treatment group summaries.


Effect of natural naphthoquinones in BALB/c mice infected with Leishmania amazonensis and L. venezuelensis.

Plumbagin, 3,3'-biplumbagin and 8,8'-biplumbagin are naphthoquinones isolated by activity-directed fractionation from a Bolivian plant, Pera benensis, used in folk medicine as treatment of cutaneous leishmaniasis caused by Leishmania braziliensis. BALB/c mice were infected with L. mexicana or L. venezuelensis and treated 24 h after the parasitic infection with plumbagin (5 or 2.5 mg/kg/day), 3,3'-biplumbagin, 8,8'-biplumbagin (25 mg/kg/d) or Glucantime (200 mg/kg/d). Lesion development was the criteria employed to evaluate the inhibitory effect. The bis-naphthoquinones were less potent than Glucantime against L. amazonensis and L. venezuelensis. Plubagin and Glucantime delayed the development of L. amazonensis and L. venezuelensis. Assays of a single local treatment on foot-pad infection two weeks after the parasitic inoculation with L. amazonensis showed that 8,8'-biplumbagin (50 mg/kg/d) was as potent as Glucantime (400 mg/kg/d).


An in vitro bioassay for quantification of melarsoprol in serum and cerebrospinal fluid.

A biological assay was developed for measuring melarsoprol in serum and cerebrospinal fluid of patients with human African trypanosomiasis. Trypanosomes were cultivated in microtiter plates for 72 hours with melarsoprol (Mel B) in concentrations of 1.25 micrograms/ml to 2.2 ng/ml. The minimum inhibitory concentration of Mel B for a reference Trypanosoma brucei rhodesiense clone was determined by microscopical examination. Samples of serum or cerebrospinal fluid were incubated under the same conditions and the highest dilution determined which caused death of all trypanosomes. The melarsoprol concentration of the sample was then calculated using the sample dilution and the determined minimal inhibitory concentration of the trypanosome population used for the assay. The test was validated using a number of reference samples and it was used for melarsoprol determination in serum- and cerebrospinal fluid samples taken from two treated patients. A sample size of 100 microliters was sufficient to perform the assay. The lower detection limit was 9 ng/ml (22.6 nmol/ml). The assay has potential for measuring other trypanocidal drugs in body fluids.


Preliminary observations on the efficacy of mel Cy (Cymelarsan) in domestic animals infected with stocks of Trypanosoma brucei brucei and T.b. evansi.

The trypanocidal activity of an arsenical compound (RM 110; mel Cy; Cymelarsan) was evaluated against Trypanosoma brucei brucei and T. brucei evansi in cultures, in goats and pigs. The trypanosome stocks used differed in their levels of susceptibility to cymerlarsan in an in vitro test, their IC50 values (drug concentration which inhibits growth by 50%) ranging from 4.8-5.1 nM for susceptible, and 26.9 nM for a resistant stock. Goats infected with a susceptible T.b. evansi stock were cured after a single injection of 0.3 mg/kg cymelarsan. In three out of four goats chronically infected with the same stock a single injection of 0.625 mg/kg cymelarsan effected a cure, whereas the goat in which the infection relapsed was finally cured after injection of 0.625 mg/kg on each of three consecutive days. A single dose of 2.5 mg/kg did not cure goats infected with an arsenical-resistant T.b. brucei stock. One of two pigs chronically infected with arsenical-susceptible stocks of T.b. brucei was cured after a single injection of 0.625 mg/kg cymelarsan, whereas the other one relapsed and died. In conclusion, the results may indicate that the dose of 0.25 mg/kg recommended by the manufacturer is too low and that a single may not cure animals with CNS involvement with certainty. The recommended dose might therefore have been applied strictly for the treatment of camels only.


Risk factors for deaths in children under 5 years old in Bagamoyo district, Tanzania.

We conducted a population based case control study of deaths in children < 5 years old from Bagamoyo District, Tanzania, to evaluate factors associated with death, and factors associated with not utilizing Government health care system. Six hundred and ten children who died between 1 July, 1986 and 30 June 1987 were enrolled as cases; 1,160 healthy control children were selected by multistage random cluster sampling. Twenty-five percent of deaths were ascribed to pneumonia based on "verbal autopsy"; 39% of acute respiratory deaths occurred in children < 6 months of age. In a multivariate analysis, significant independent associations were found with mother as sole decision maker for treatment (O.R = 0.13; 95% C:I. 0.07, 0.22); use of water from village well, pond, or river vs. tap water (O.R. = 11.86; 95% C.I., 5.46, 25.72); the child eating with others (O.R. = 9.42; 95% C.I. 5.68, 15.62) and the child sleeping in the room where cooking is done (O.R. = 2.78; 95% C.I. 1.79, 4.33). Overall only 45% of families utilized Government health care (village health worker, dispensary or health centre) during their child's terminal illness. Families utilizing Government health care were significantly more likely to say that the mother alone could make treatment decision (O.R. = 2.49, 95% C.I. 1.39, 4.46), and to be closer to a dispensary. The main reasons for not utilizing Government health care were 'traditional medicine is better' (41%) and 'no drugs available' (38%).


Perception of risk for malaria and schistosomiasis in rural Malawi.

A sample of 120 individuals--representative of the Malawian population in terms of gender and age distribution--were interviewed regarding their perceptions of the diseases malaria and schistosomiasis. Particular attention was paid to judgements regarding the level, seriousness, predictability and controllability of these health risks. Sample sites were lowland marshland areas where both diseases were highly prevalent. Individuals were also asked about their adherence to recommended malaria and schistosomiasis control and prevention procedures. Respondents commonly rated malaria and schistosomiasis both unpredictable and uncontrollable. For malaria, no risk judgements predicted level of adherence to prevention guidelines. That is, individuals' perception of malaria risk bore no influence on whether or not they engaged in recommended behaviour. For schistosomiasis, seriousness of infection (at one sample site) and the predictability and controllability of infection (at the other sample site) predicted such adherence. Analysis of the influence of factors such as age, gender and level of education confirmed distinct patterning or responses for the two health risks. Whilst adherence to preventative guidelines for schistosomiasis is influenced by personal perceptions of risk, it appears that social factors may exert more influence on the extent of compliance with malaria control and prevention procedures. Distinct approaches to health education regarding malaria and schistosomiasis may, therefore, be warranted, with the former emphasising community responsibility and participation, and the latter individual actions which may reduce risk.


Analysis of ecdysteroids in the trematodes, Schistosoma mansoni and Fasciola hepatica.

Adult Schistosoma mansoni from experimentally infected mice and Fasciola hepatica recovered from ovine livers post mortem were analyzed for free and conjugated ecdysteroids by radioimmunoassay, high-performance liquid chromatography monitoring fractions by radioimmunoassay, and by capillary gas chromatography/mass spectrometry (selected ion monitoring). Both species contained ecdysone and 20-hydroxyecdysone as free ecdysteroids and as polar conjugates. F. hepatica also contained a polar conjugate of 2-deoxyecdysone. Evidence of apolar ecdysteroid conjugates was only obtained for F. hepatica. The free ecdysteroid-containing fraction of S. mansoni contained small amounts of unidentified immunoreactive material.


Ultrasound versus clinical examination as indication for Schistosoma mansoni associated morbidity in children.

In order to compare clinical versus ultrasound based diagnosis of Schistosoma mansoni induced periportal fibrosis (pF) 536 infected Sudanese schoolchildren underwent clinical and sonographical examination. A liver exceeding 3 cm in sternal line and a palpable spleen were considered pathological. Ultrasound criteria for age dependent organometry of a Central European cohort were used as reference. Based on clinical criteria 190 children (35.4%) had hepatomegaly, whereas according to ultrasound results the rate was only 11.4%. Splenomegaly was detected in 77 cases (14.4%) by clinical means, but in 196 by ultrasound (36.6%). The sensitivity of clinical parameters as indication of pF was around 50%. Results for ultrasound detected organomegaly were only slightly better. It was concluded that assessment of liver and spleen sizes was of limited value as an indication for pF and that a considerable discrepancy existed between clinical and ultrasound based assessment of hepato- and splenomegaly.


Paragonimiasis in Ecuador: prevalence and geographical distribution of parasitisation of second intermediate hosts with Paragonimus mexicanus in Esmeraldas province.

To determine whether the human cases of pulmonary paragonimiasis detected in the province of Esmeraldas were autochthonous a total of 1,457 freshwater crabs, species Hypolobocera aequatorialis, were collected from 45 different streams in 4 cantons to determine the rate of parasitisation with metacercariae of Paragonimus mexicanus. Some 28 (62.2%) streams were found to harbour parasitised crabs, with 76.5% of the streams in canton Quininde infected, followed by those in Muisne, 72.7%, Esmeraldas, 62.5% and Eloy Alfaro 22.2%. Of the 1,043 crabs studied from these 28 streams, 42.6% (444) were found to be parasitised with metacercariae: 45.1% of the crabs in the streams in the canton of Quininde, 43.9% in Muisne, 37.4% in Esmeraldas and 13.2% in Eloy Alfaro. There was a positive correlation between the crab parasitisation and the increasing size of their carapace. The results indicate that there is potential active transmission of disease in the four cantons in the province of Esmeraldas and that the human cases detected are probably autochthonous.


First record of Angiostrongylus cantonensis (Chen, 1935) (Nematoda: Metastrongylidae) in the Dominican Republic.

Rats, Rattus norvegicus, trapped in some sections (barrios) of the city of Santo Domingo, the capital of the Dominican Republic showed that 5 of them from two barrios harbored the nematode Angiostrongylus cantonensis in the pulmonary artery. Macerated and digested terrestrial snails, Subulina octona, collected from the backyards of houses where the rats were trapped contained L2 and L3 larvae of the nematode. The morphology of the adult worms and the larvae was consistent with that described for A. cantonensis in the literature. This is the first report of this Oriental and Western Pacific nematode in the Dominican Republic and the fourth in the Americas. Gastrointestinal hemorrhage, a rare symptom due to another species, the American A. costaricensis, which occurs in mesenteric arterioles of rodents and humans, is in the recent literature; the patient was a 41-year old Dominican. Thus the Dominican Republic is the first country in the Western Hemisphere to have the two species of Angiostrongylus.


The effect of repeated doses of ivermectin on adult female Onchocerca volvulus in Sierra Leone.

The effects of single and multiple doses of ivermectin on mortality and morphology were assessed in over 700 female Onchocerca volvulus worms and the effects on embryogenesis were assessed in 490. Nodules were surgically removed from Sierra Leoneans recruited from a double-blind placebo controlled study of ivermectin given at six-monthly intervals. Nodules were digested in collagenase to isolate whole adult worms. After four or five doses of ivermectin there were significant increases in the numbers of discoloured and calcified worms and possibly a trend towards increased mortality, but this was not seen consistently. There was no evidence of a prophylactic effect of the drug. Worms were then homogenised and embryograms constructed. A single dose of ivermectin produced large numbers of degenerating intrauterine microfilariae, but embryonic development occurred normally. After multiple doses we observed almost complete cessation of embryogenesis, with a highly significant decrease in the numbers of viable multicellular embryonic stages, while oocytes appeared to be produced normally. Development is probably impeded at the single cell stage, possibly because of reduced fertilization. In planning the future role of ivermectin as a control measure for onchocerciasis it is crucial to determine if these effects on embryogenesis are reversible.


Results of a safety trial on single-dose treatments with 400 mcg/kg of ivermectin in bancroftian filariasis.

Two groups of Polynesian Wuchereria bancrofti carriers, 17 females aged 21 to 84 years and 20 males aged 26 to 57 years, in whom microfilaraemia ranged from 1 to 10,121 mf/ml and from 1 to 6,484 mf/ml, respectively, were given a supervised singledose treatment with 400 mcg/kg of ivermectin. Carriers were examined and questioned regarding their experience of adverse reactions, which were graded 0 to 3 according to severity, at 6, 12 and 24 hours and at 4 days after treatment. Biological examinations which included determination of microfilaraemia, complete blood count, liver function tests and assessment of creatinine and urea levels were performed at 4 days before and 4 days after treatment. Adverse reactions were observed in 65% of female and in 70% of male carriers; they were of grade > or = 2 in 35% of carriers in both groups. None as considered serious; they all disappeared in 24-48 hours. The main symptoms were headache, fever > or = 37.5 degrees C and myalgia in females. One male vomited 3 hours after treatment; as a result the drug was not ingested and no decrease of microfilaraemia was noted. Twelve days afterwards, he was given a second 400 mcg/kg dose, he experienced again a grade 1 reaction and his microfilaraemia fell to zero. The 37 carriers in the present study were matched with 37 other Polynesian carriers treated with a 100 mcg/kg single dose of ivermectin in previous trials for pretreatment mf density and sex: no significant difference could be found in adverse reactions between the 2 treatment groups.(ABSTRACT TRUNCATED AT 250 WORDS)


The selection of communities for treatment of onchocerciasis with ivermectin.

In areas endemic for onchocerciasis, active community-based treatment with ivermectin is preferred to individual diagnosis and treatment. Ideally, all infected persons should be treated, although initially priorities may have to be set at local or national levels. We suggest that all communities with a prevalence of O. volvulus infection of 20% or more in adult males aged 20 years or over should be treated; and that elsewhere facilities for passive treatment should be provided. In some areas, for logistical reasons, treatment may first have to be started in communities with the highest prevalences (perhaps above 40% or even 60%) and then expanded to all endemic communities. The available data suggest that a rapid assessment method based on the examination for nodules will give a simple, acceptable, non-invasive and reasonably reliable method of identifying the communities that should be treated. If a nodule is detected in at least three men from a sample of 30 men aged 20 years or over, the community can be assumed to have a true prevalence of infection of 20% or more and should be included in community-based treatment.


Expression of an active cathepsin B-like protein Sm31 from Schistosoma mansoni in insect cells.

Recombinant Schistosoma mansoni cathepsin B was produced in insect cells via the baculovirus expression vector system as a 37.5 kDa precursor molecule and a 31 kDa mature enzyme. Extracts prepared from cells infected with the recombinant virus were able to cleave a synthetic dipeptide substrate specific for cathepsin B. Proteolytic activity was inhibited by trans-epoxysuccinyl-L-leucyl-amido (4-guanidino) butane (E64) but not by phenylmethylsulphonyl-fluoride (PMSF), pepstatin and 1,10-phenanthroline. Specific inhibition by diazomethylketone derivatives, which bind covalently to the active centre of cysteinyl proteinases was also demonstrated.


Serum TNF in patients with severe malaria treated by exchange transfusion.

The authors report on three cases of severe P. falciparum malaria successfully treated by iv quinine and exchange transfusion. Serum concentrations of Tumor Necrosis Factor (TNF) were determined before and during treatment. After an initial decrease, serum levels of TNF remained markedly elevated during the first 48 hours despite exchange transfusion. Though exchange transfusion accelerates the elimination of parasites from the blood, it seems to have no immediate effects on reducing serum levels of cytokines such as TNF.


The newborn with ambiguous genitalia.

The unexpectedness of genital ambiguity in an infant creates an urgent and stressful situation. A logical approach, using a team of specialists together with nursery staff and physicians, allows each member to contribute expertise and unnecessary overlap of investigations. The psychological needs of the parents should be recognized, because their relation with the infant will determine the success of the assigned gender role in the future.


Human congenital anomalies: application of new genetic tools and concepts.

The discovery of nontraditional inheritance and of developmental gene families common to all metazoans has revolutionized research on human congenital anomalies. The most gratifying results of these new concepts are summarized in Table 5: several human syndromes have already been related to their causative genes. Classic embryonic mechanisms (ie, gastrulation, segmentation, adhesion) also have been correlated with specific molecules. Perhaps most optimistic are the facts that many of the relevant molecules can be viewed as growth factors and that many anomalies are examples of extended or arrested development known as heterochrony. The implication is that genetic screening and preconceptional diagnosis will allow treatment of congenital malformations by supplementation/suppression of the maternofetal unit. This future specialty of "gestational endocrinology" is already being used for embryonic therapy of 21-hydroxylase deficiency.


[Effect of norepinephrine on the frontal neuron activity related to delayed discrimination task in monkeys].

To study the role of norepinephrine (NE) in the cognitive function of the brain, the effects of NE, tolazoline (TOL) and propranolol (PR) on the activity of frontal neurons were examined in 3 rhesus monkeys (Macaca mulatta) during the performance of a delayed visual discrimination go/no-go task. Of the 230 task-related neurons recorded from the area medial to the superior ramus of the arcuate sulcus, 159 neurons were tested with NE applied microiontophoretically. Of these tested neurons, 11 neurons were related to starting period, 28 neurons to cue period, 66 neurons to delay period and 54 neurons to response period. About 2/3 of these neurons increased in discharge rate in the task, and the rest decreased. For most of the neurons with decrease of discharge rate in the delay period, the discharge rate was further decreased during application of NE. During application of TOL or PR, the discharge rate was increased and the effect of NE was antagonized. The present results suggest that NE may play a role in the cognitive function of the frontal neurons, particularly in attention and short-term memory, and may be involved in the inhibitory process of the neuronal activities.


[Antagonistic effect of electro-acupuncture analgesia with Ca2+ injection into habenula could be reversed by gallamine triethiodide].

.1 mol/L CaCl2 0.5 microliters, 0.06 mol/L ACh 0.5 microliters, 5.4 x 10(-3) mol/L gallamine triethiodide (cholinergic nicotinic receptor blocker) 0.5 microliter and 14.4 x 10(-3) mol/L atropine (cholinergic muscarinic receptor blocker) 0.5 microliter were injected through bilateral intracranial cannulae in rat habenula. Pain threshold was measured by the latency of tail-flick reflex elicited by radiant heat exposure before and after intracerebral injection. CaCl2 significantly reduced the basic pain threshold and weakened the effect of the acupuncture analgesia. ACh apparently antagonized the effect of acupuncture analgesia. Gallamine triethiodide could recover the pain threshold almost to the raised level by acupuncture, but atropine only strengthened the effect on pain threshold weakly and briefly. The results suggest that the antagonistic effect of Ca2+ may be mediated via ACh in habenula.


[Simple spike response of cerebellar Purkinje cells to stimulation of C-fiber in saphenous nerve].

Simple spike of cerebellar Purkinje cells (PC-SS) was recorded with microelectrode. In the NCCVF (normalized cross-covariance function) histogram, spontaneous PC-SS does not show obvious peak. When the saphenous nerve is stimulated at lower intensities, which elicits the A-fiber input only, the discharge response (A-CED) consists of an early component with a latency of 16.7 +/- 0.9 ms and a late component with a latency of 270.8 +/- 12.8 ms. After A-fibers are blocked selectively by polarizing current, the stimulation at a suprathreshold strength for C-fiber evokes a characteristic response (C-CED) with a latency of 142.4 +/- 4.3 ms. However, the C-CED can not be evoked by the inputs of A- and C-fiber simultaneously. In NPSDF histogram, the spontaneous activities of PC-SS can be divided into two groups, the high and the low peak group. The high peak group (n = 15) has a peak energy value of 15.7 +/- 4.7 x 10(-3) and peak frequency of 4.07 +/- 1.69 Hz. A-fiber input causes an increase of the peak value, while C-fiber input causes a decrease. The low peak group (n = 16) has a peak energy value 8.4 +/- 1.4 x 10(-3) and peak frequency of 3.67 +/- 2.90 Hz. Both A-fiber and C-fiber inputs cause an increase of the peak value, but the effect of A-fiber input was more prominent. The results show that the pure C-fiber input can reach the cerebellar PC and elicit characteristic simple spike response.


[Relationship between neuronal activities of the guinea-pig inferior mesenteric ganglion neurons and muscular contraction of the colon in vitro].

A perfused inferior mesenteric ganglion (IMG)-colon preparation was prepared from the guinea-pig for intracellular recording of IMG neurons and for simultaneously recording the muscular contraction. It was found that: (1) At zero preloaded tension of colon, the spontaneous fast excitatory post-synaptic potentials (f-EPSPs) could be recorded in about 50% sampled neurons. These f-EPSPs were abolished by either severing the colonic nerve or superfusing IMG with d-tubocurarine (d-TC, 50 mumol/L). (2) The contraction of circular but not longitudinal muscle was augmented and slowed down by superfusing IMG with d-TC or low Ca/high Mg solution. (3) A train stimulation of the preganglionic nerves initiated a volley of f-EPSPs or orthodromic discharges, in the IMG neurons and a quick relaxation of the longitudinal muscle with a latency of between 0.1 s and 0.2 s. The responses of the neuron and the muscle could be eliminated by superfusing IMG with d-TC. Multiple irregular responses of the circular muscle of the colon to the train stimulation could also be found. The results suggest that the IMG neurons participate in the cholinergic afferents and colo-colonic reflex mediated by cholinoceptors. The output of the reflex mainly inhibited the circular muscle contraction of the colon.


[Changes of central glucose metabolism following caudate stimulation produced analgesia in the rat--an autoradiographic deoxyglucose A study].

Sokoloff's 2-deoxyglucose (2-DG) autoradiographic technique was used to identify changes of glucose metabolic rate in the rat brain following unilateral stimulation of the head of the caudate nucleus. The results were as follows. The local glucose metabolic rate after noxious stimulation was increased in the somatosensory cortex, cingulate cortex, ventroposterior and parafascicular nucleus of the thalamus, septal area, habenular nucleus, head of caudate nucleus, periaqueductal gray (PAG) and dorsal raphe nucleus (P < 0.05). After stimulating the head of the caudate nucleus, the local glucose metabolic rate of nucleus raphe magnus (rm) and nucleus paragigantocellularis (pgcl) was increased significantly and that of the PAG and dorsal raphe nucleus had a tendency to increase, while stimulation of the head of caudate nucleus could partially abolish the increased glucose metabolic rate in the somatosensory cortex, cingulate cortex, ventroposterior and parafascicular nucleus of the thalamus, septal area and habenular nucleus as induced by noxious stimulation. These results suggest that caudate stimulation is able to depress the activation of some brain structures related to nociception and to activate those related to antinociception. The pgcl, rm, PAG and dorsal raphe nucleus might be the key structures participating in the caudate stimulation produced analgesia.


[Inhibition of dopamine on WDR neurons of dorsal horn not antagonized by phentolamine and naloxone in rats].

The inhibitory effects of dopamine (DA) applied spinally on the wide dynamic range (WDR) neurons of dorsal horn in rats were studied with extracellular recording technique. 54 WDR units were tested from 43 rats. With a dosage of DA from 0.26 x 10(-6) to 1.58 x 10(-6) mol/kg, the inhibitory effect of the neurotransmitter on the responses of dorsal horn neurons to noxious transcutaneous electrical stimulation exhibited a gradual increase. After DA (0.52 x 10(-6) mol/kg) administration, the inhibitory effect of DA began to appear in 5 min and reach to maximum in 15 min, whereupon the maximum level could be maintained for about 25 min. This effect of DA could be reversed completely by dopaminergic receptor antagonist, droperidol (0.66 x 10(-6) mol/kg) but not by 2.65 x 10(-6) mol/kg phentolamine or 1.37 x 10(-6) mol/kg naloxone. The results of the present investigation suggest that DA may be involved in the modulation of nociception at the spinal level as an independent neurotransmitter.


[Guiding effect of embryonic fimbria graft on cholinergic fiber growth in hippocampus of adult rats].

In view of the fact that in embryonic and neonatal central nervous system (CNS), the pathway of developing fiber tracts is capable of guiding the axonal growth, it would be interesting to know whether a similar effect exists on the axonal growth in adult CNS. Embryonic fimbria was grafted into the hippocampus of the adult rat. Two weeks later, the grafts were examined for cholinergic fibers with AChE histochemical method. It was found that a lot of cholinergic fibers appeared in the embryonic graft, but none of them in the adult fimbria graft as control. If the fimbria-fornix was transected at the time of grafting, no cholinergic fibers could subsequently be detected in both the embryonic graft and the host hippocampus. If a suspension of embryonic fimbria was used as a graft, only a few of long cholinergic fibers could be found in the grafted area. However, if tissue fragments of embryonic fimbria adhered to a strip of nitrocellulose filter were grafted as previously, numerous cholinergic fibers from the host hippocampus were found to be attracted around the strip and grow along the surface of the filter. The results seem to indicate that grafted embryonic fimbria or its tissue fragments are able to guide cholinergic fiber growth in adult hippocampus. It is possible that embryonic fimbria and other pathways of developing CNS fiber tracts provide a natural substrate for guiding axonal growth in adult CNS.


[Alteration of calcium uptake and Ca(2+)-ATPase activity of cardiac sarcoplasmic reticulum in rat during ischemia-reperfusion].

Using Langendorff's perfusion model of isolated rat heart, the effect of period of ischemia, ischemia-reperfusion and changes in perfusate pH on the function of calcium uptake of cardiac sarcoplasmic reticulum (SR) was observed. The initial rate and capacity of calcium uptake by SR decreased significantly after 25 min ischemia, and were further worsened when ischemia was prolonged to 40 min. When hearts were subjected to 15 min reperfusion after 25 min ischemia, calcium uptake capacity and initial rate decreased even more in comparison with that of 40 min ischemia. In addition, the calcium dependent ATPase activity of SR was also markedly inhibited. Reperfusion with acid (pH 6.8) or alkaline (pH 8.0) made no significant difference on the aforementioned reperfusion induced changes. The results indicated that myocardial ischemia depressed the calcium transport activity of SR, and this depression was further aggravated with prolonging ischemia. Reperfusion after ischemia exacerbated the ischemic injury. Reperfusion with either acid or alkaline Krebs-Henseleit solution could not improve the calcium uptake function of SR, implying that the pH change does not seem to be an important factor in inducing the SR dysfunction during ischemia-reperfusion.


[Role of sulfhydryl compounds in the oxygen radical induced injury of isolated gastric mucosal cells].

Gastric mucosal cells were separated by pronase-EDTA method and cultured. The cellular injury was produced by oxygen radicals provided by xanthine oxidase(XO)-xanthine(X) system. When the cells were subjected to the action of XO-X system, the cellular viability was decreased and leakage of lactate dehydrogenase (LDH) from the cells was significantly increased. In addition, the cellular contents of nonprotein sulfhydryls (NPSH) and protein sulfhydryls (PSH) were decreased. When the intracellular sulfhydryl content was decreased by N-ethylmaleimide (NEM, a depletor of endogenous sulfhydryls), the cell mortality and LDH leakage were increased in a time-dependent and dose-dependent manner. If glutathione or cysteamine (compounds containing-SH) was administered into the media, the cellular injury induced by XO-X system was notably inhibited, also in a dose-dependent manner. The above results suggest that sulfhydryls may play an important role in the cell defending mechanism against injury of gastric mucosal cells by oxygen radicals.


[Induction of Fos-like protein in the rat spinal cord following electroacupuncture stimulation].

The expression of the c-fos proto-oncogene has been regarded as a marker for noxious stimulation. We now report that electroacupuncture (EA) stimulation (100 Hz, 0.3 ms, 1-2-3 mA, 30 min) delivered into the acupoint Sanyinjiao (SP6) could also induce the c-fos expression in the rat spinal cord as demonstrated by immunohistochemical technique using antibody against the c-fos protein product Fos. In rats receiving EA stimulation, numerous cells with Fos-like immunoreactivity (FLI) were observed in both dorsal and ventral horn of the spinal cord with dense labelling in laminae III and IV of the ipsilateral side. Only scattered FLI cells were found in laminae I and II. In contrast, FLI evoked by noxious stimulation (5% formalin injected at the hindfoot subcutaneously) was shown mainly in laminae I and II, rather than in III and IV. The c-fos expression was very low in control animals receiving neither formalin nor EA administration. The present study indicates that the site specificity of the c-fos expression induced by EA is different from that evoked by noxious stimulation. The possibility that EA-induced Fos protein might participate in acupuncture analgesia is currently under investigation.


[Cardiovascular effects of microinjection of neuropeptide Y into lateral septal nucleus].

Cardiovascular effects of microinjection of neuropeptide Y (NPY) into the lateral septal nucleus (LS) were investigated in anaesthetized rats. The microinjection gave rise to a significant increase in blood pressure and heart rate. The pressure response was dose-dependent but the tachycardia was not. Control injection of 0.9% saline into LS produced no haemodynamic response.


[Stimulation of the brain osmoreceptor attenuates the sensitivity of tubuloglomerular feedback in rats].

By using micropuncture technique and measuring inulin concentrations in plasma and tubular fluid, and tubular flow rate, single nephron glomerular filtration rate (SNGFR) was calculated. The effect of stimulation of the brain osmoreceptors on the sensitivity of tubulo-glomerular feedback in rats was observed. The SNGFR value measured at the proximal tubular (SNGFRp) was greater than that measured at the distal tubule (SNGFRd) of the same nephron. The difference between these two values (SNGFRp-d) was a measure of the extent of tubuloglomerular feedback (TGF). The SNGFRp-d value was reduced after intracerebroventricular administration of hypertonic saline (icv. HS), indicating that stimulation of the brain osmoreceptor can attenuate the sensitivity of TGF. The icv. HS-induced increase in renal plasma flow rate and glomerular filtration rate could be abolished by intravenous injection of furosemide, while natriuretic response persisted. These results suggest that icv. HS can alter renal hemodynamics via reduction of TGF, and confirm the claim that icv. HS can inhibit tubular reabsorption, which is responsible for the natriuretic response.


[Preliminary study on the effect of endothelin on the contraction of isolated rat pulmonary artery and its mechanism].

Experiment was performed on the rings of right pulmonary artery (PA) taken from male Wistar rats. Each ring was suspended in an organ bath (37 degrees C) containing Krebs solution, gassed with 95% O2-5% CO2 (pH7.40). The changes of vascular tension were measured. The contraction of PA to endothelin (ET) (10(-9) mol/L) and the effects of 764-3 (50, 100, 200, 300 micrograms/ml as a scavenger of superoxide anion), verapamil (3 x 10(-6) mol/L) NDGA, indomethacin, atropine, phentolamine, propranolol, ketanserin tartrate and diethylcarbamazine on the ET-induced contraction were investigated. The results indicated that ET can induce a potent and sustained contraction of PA, inhibited by verapamil and 764-3, but unaffected by inhibitors of cyclooxygenase, lipoxygenase, leukotrienes systhetase or adrenergic, serotonergic, cholinergic receptors. It is suggested that the influx of extracellular Ca2+ and the production of superoxide anion might be involved in the ET-induced contraction. Arachidonate metabolism and receptors mentioned above probably didn't participate in the responses.


[Use of a computer-controlled servo system to produce "ephysiological" contraction of isolated rat papillary muscle].

A computer-controlled servo system consisting of an ergometer with a force-displacement dual mode transducer, a Z-80 single-board microcomputer and a designed software was constructed. This servo system can be used to generate physiological contraction in isolated rat papillary muscle, in which the muscle went through a complete 4-phase cycle of force and length changes, similar to those undergone by muscle fibers in the beating heart during the cardiac cycle. This system is being used to investigate the tension-length relation and the network of isolated myocardium as well as the end-systolic tension-length relation and the force-velocity relation simultaneously.


[Neurotensin excited neurons of the dorsal motor vagal nucleus: an in vitro study].

Intracellular recordings were made from neurons of the dorsal motor nucleus of the vagus (DMV) in rat brain slices. Most of DMV neurons (88%) were depolarized by droplets or perfusion of neurotensin (NT) in a dose-dependent manner. The depolarization, accompanied by an increase in membrane resistance, depended on extracellular K+ concentration and reversed polarity at about -82 mV. Perfusion with Ca(2+)-free/high-Mg2+ solution or with 1 mumol/L TTX solution, which blocked synaptic activities, did not eliminate NT-induced depolarization. The results indicate that NT excites DMV neurons through postsynaptic mechanism and this exciting depolarization may result from a decrease in K+ conductance.


[Involvement of vasopressinergic neurons of paraventricular nucleus in the electroacupuncture-induced inhibition of experimental visceral pain in rats].

It has been demonstrated in animal model of somatic pain that hypothalamic paraventricular nucleus (PVN) participates in acupuncture analgesia, probably by mediation of vasopressin release. The role of PVN in acupuncture analgesia for experimental visceral pain in rats was further investigated in the present study. Experimental results demonstrated that electroacupuncture could inhibit the writhing response, produced by intraperitoneal injection of antimonium potassium tartrate and this inhibitory effect could be enhanced by electrical stimulation of PVN, but decreased by electrolytical lesion of PVN, intracerebroventricular injection of vasopressin antiserum (14 microliters) or the vasopressin antagonist, d(CH2)5Tyr(Me)-AVP (500 ng/5 microliters). Intraperitoneal administration of the latter drug (10 micrograms/kg), however, was ineffective. The above experimental results suggest that vasopressinergic neurons in PVN also participate in the inhibition of visceral pain by electroacupuncture.


[Effects of intrahippocampal injection of 6-OHDA on acquisition and retention of avoidance response in rats].

The role of hippocampal noradrenergic and dopaminergic transmission in the acquisition and retention of active conditioned avoidance behavior was investigated in rats by injection of 6-hydroxydopamine (6-OHDA) into dorsal hippocampus. The main results are as follows: (1) After injection of 6-OHDA the contents of dopamine, particularly norepinephrine (P < 0.01) in the hippocampus was decreased significantly. (2) The acquisition of conditioned avoidance behavior was markedly impaired. (3) The facilitating effect of AVP on retention of active conditioned avoidance behavior could be eliminated by prior injection of 6-OHDA bilaterally into hippocampus.


[Effect of injection of enkephalin and bestatin in caudate-putamen on operant conditioning in rats].

Female Wistar rats were trained in a Skinner-box, 30 trials per day in a dark room to establish operant defence conditioning. Training started with a light (15 s), then combined with footshock for further 8 s. When the rats learned to press the key to avoid footshock within 15 s, conditioned response was considered established. After the rats reached a conditioning rate (CR) above 80% for 5 days, cannulae were implanted into caudate-putamen. Two to three days later, Met-enkephalin (MEK) or bestatin (an aminopeptidase inhibitor) was injected bilaterally into caudate-putamen. 30 min, 2 h, 24 h and 48 h after injection, conditioning tests were conducted, with each session consisting of 30 trials. Control experiments were done when 0.9% NaCl (NS) was injected. After injection of NS, CR maintained above 80% in all 4 test sessions. MEK (60 ng/rat) or bestatin (10 micrograms/rat) significantly lowered the CR during the 30 min and 2 h test session. In the latter case, the latency (L) was also prolonged. However both CR and L returned to the control level in the 24 h and 48 h test sessions. Naloxone (2 mg/kg, i.p.) blocked the conditioning-depression effect of bestatin. No significant alteration was seen in locomotor activity after MEK or bestatin injection. The results suggest that enkephalin in caudate-putamen may be involved in the regulation of retrieval of conditioning. Bestatin mimics the effect of MEK on conditioning reflex probably by increasing production of endogenous enkephalin.


[Effects of stimulation and cauterization of hypothalamic paraventricular nucleus on acupuncture analgesia].

The role of hypothalamic paraventricular nucleus (PVH) in acupuncture analgesia was investigated by local brain stimulation and cauterization. The results showed that electrical or L-glutamate sodium stimulation of PVH could enhance the effect of analgesia of Zusanli acupuncture, both in a dose dependent manner. Electrical cauterization of PVH decreased the effect of acupuncture analgesia, while removal of pituitary had no effect on the enhancing effect by L-glutamate sodium injection.


[A voltage-dependent potassium channel of outward rectifier type in plasma membrane of oocyte from toad, Bufo bufo gargarizans].

Membrane properties of the fully-grown oocytes from toad, Bufo bufo gargarizans, were studied by using voltage-clamp technique. It was found that a sustained outward current was elicited by membrane depolarization to -30 mV or more positive value. The increase of the current was nearly proportional to the degree of depolarization. The peak value of the current ranged 2-5 microA at a membrane potential of 20 mV in oocytes from different toads. The current was inhibited by antagonists of potassium channel, TEA and 4-AP. The concentration of TEA capable of inhibiting half of the current was 2.6 mmol/L. Chloride channel antagonist 9-AC (2.5 mmol/L) had no effect on the current. Triple the extracellular calcium concentration did not show any effect either. The reversal potential of the current varied with an increase of 47.3 mV per decade change of the extracellular potassium concentration. Changing extracellular concentration of sodium or chloride did not shift the reversal potential. It was concluded that the outward current was a voltage-activated potassium current. The voltage-dependent potassium current decreased after treatment of the oocytes with progesterone to a state of maturation. A large decrease of the current (to about 1/20 of the control) occurred to the oocytes obtained from hibernating toads while a less striking decrease of the current (to about 1/3 of the control) was observed in the oocytes from toads all year round reared at 25-30 degrees C.


[Different changes in renal sympathetic nerve activity and adrenal sympathetic nerve activity produced by hemorrhage].

The present study was undertaken to investigate the changes in renal sympathetic nerve activity (RSNA) and adrenal sympathetic nerve activity (AdSNA) due to acute hemorrhage in anesthetized rabbits. The animals were bled to a mean arterial pressure (MAP) of 5.3 kPa within 10 minutes from the femoral artery. Acute hemorrhage elicited a biphasic responses of RSNA with an initial excitation and a late inhibition during hemorrhage. But hemorrhage only induced a lasting excitation in AdSNA which could be abolished by sino-aortic denervation (SAD). Bilateral vagotomy either before or after hemorrhage could reverse the late inhibition in RSNA, but did not abolish the excitation in AdSNA. Intravenous injection of naloxone or microinjection of naloxone into rostral ventrolateral medulla (RVLM) could reverse the late inhibition in RSNA, but had no significant effect on the initial excitation in RSNA and AdSNA during hemorrhage. Hemorrhage-induced heart (HR) change was similar that in RSNA, but could not be reversed by naloxone. These results indicate that the late inhibition in RSNA is mediated by inputs from vagus nerves and opiate peptide, particularly that in RVLM, and the excitation in AdSNA during hemorrhage is related to arterial baroreceptor reflex.


[Inhibitory effect of transferrin on the binding and maintenance of FSH receptors in rat granulosa cells].

It has been recently demonstrated that transferrin (TRF) can inhibit the functional differentiation of rat granulosa cells, but the mechanism remains unknown. In present experiment, the effect of TRF on the binding of 125I-rFSH to receptors and on the maintenance of FSH receptors in granulosa cells from immature, diethylstilbestrol treated rats were studied. The results show that the physiological range of TRF partially blocked the binding of 125I-rFSH to granulosa cells in a dose-dependent manner. TRF also dose-dependently inhibited the maintenance of FSH receptors in accordance with the reduced production of progesterone and estradiol. In view of the present and our previous investigation, it could be concluded that mechanisms of the inhibitory effect of TRF on the functional differentiation of granulosa cells mainly involve blockade of FSH binding to its receptors and inhibition of FSH receptor maintenance by FSH.


[Plasminogen activators and plasminogen activator inhibitor type-1 in human endometrium].

Two types of plasminogen activator (PAs) are present in human endometrium, and their contents vary with the different phases of menstrual cycle, i.e. high in the proliferative phase and low in the secretory phase. In the present study by immunohistochemical technique, both uPA and tPA antigens were demonstrated in the stromal and glandular cells of the endometrium. In cell culture, tPA was released only from stromal cells and uPA only from glandular cells as determined by SDS-PAGE followed by fibrin overlay technique, but PA inhibitor type-1 (PAI-1) was secreted by both stromal and glandular cells. Furthermore, secretion of PAs from endometrial cells was enhanced by adding estradiol and markedly inhibited by progesterone in a dose dependent manner, while the PAI reacted just in the opposite way. The effect of the peptide hormones, hCG, GnRH, PRL, as well as cAMP in cell culture on the secretion of PAs and PAI was similar to that of estradiol, while forskolin demonstrated definitely more stimulative effect on tPA than uPA. Taking into account of the finding of the present study, it appears that, under hormonal control, a balance between PAs and PAI in the endometrium exists. The physiological roles of the PAs and PAI in the endometrium were discussed.


[Cardiovascular responses to microinjection of atrial natriuretic peptide into ventrolateral medulla of rat].

Application of atrial natriuretic peptides (alpha-ANP and AP III) to glutamate sensitive area of ventrolateral medulla produced a dose-dependent decrease in MAP and HR in anesthetized rats. Lower dosage of AP III induced hypotension without bradycardia, whereas the higher dosage of AP III decreased both blood pressure and heart rate. The results suggested that ANP may inhibit the medullary sympathetic center.


[Effect of anoxia on the growth of cultured neurons from embryonic chick forebrain].

Pure neurons from embryonic day 8 chick forebrain were cultured under anoxic condition (95% N2 and 5% CO2). After 24, 48 and 72 h in culture, MTT colorimetric microassay showed a reduced production of formazan, indicating that the neurons were seriously damaged. In addition, the glucose of the cultured media was significantly depleted. Even when glucose concentration was increased to 800-1,200 mg/100 ml, anoxia still caused neurons to die. The results indicate that brain neurons in embryo are sensitive to anoxia, and any protective influence of glia on anoxic neurons could not be mediated by supplying the latter with glycogen.


[Study on zinc resistance to the immunosuppression caused by cyclophosphamidum in the mouse].

Swiss mice were used to study the effect of zinc in antagonizing the suppressive action of Cy on the immune function and thymus structure. Mice (weighing 18-22 g) receiving daily dose of 0.2 mg zinc for 25 days did not show any change in peripheral WBC count, production of IgM antibody and thymus weight, but did display marked resistance to the reduction of WBC count and number of mature T lymphocyte, suppressed production of IgM antibody and decreased thymus weight due to administration of Cy.


[Non-Hodgkin's lymphomas. I. Clinico-biological features of 307 cases].

To assess the clinico-biological features appearing in 307 patients with non-Hodgkin's lymphomas (NHL). The clinical records of 338 patients diagnosed of NHL between January 1975 and December 1988 were revised in retrospect. All cases with histologic diagnosis of NHL aged over 14 years were included, and classified in accordance with the Working Formulation criteria. The following data were analysed: age, sex, first complaints, time elapsed since onset, histologic type, number of sites involved, bulky disease, anaemia, thrombocytopenia, LDH, stage, type of treatment and initial response, survival, and cause of death. The statistical evaluation was performed by actuarial analysis (Kaplan and Meier) and comparison (log-rank test) of survival. According to the three categories of the malignancies, the NHL were distributed into low-grade (37.8%), intermediate (36.1%) and high-grade (26.9%). The mean age of the series was 56.6 years and the M/F ratio was 1.3. Lymph node enlargement was the commonest finding; 36.4% of the patients had symptoms related with the disease, and 26.7% had bulky disease. Anaemia was present in 37.7% of the cases and thrombocytopenia in 14.3%, with similar distribution among the three grades. High LDH levels were found in 44% of the patients. At diagnosis, 85% of the patients were in advanced stages (III+IV) already. Complete response was attained in 51.1% of the cases, with median survival of 48 months. The clinico-evolutive data found here are similar to other reports in the literature. In one-half of the patients the cause of the first visit is lymph node enlargement. Complete remission is achieved by one out of two patients, this figure being similar for each of the histologic groups. The Working Formulation is useful in determining the different prognostic groups with respect to survival.


[Non-Hodgkin's lymphomas. II. Analysis of the prognostic factors in a series of 307 patients].

To analyse different clinico-biologic data in order to assess their prognostic value in non-Hodgkin's lymphoma (NHL) patients. The series comprises 307 patients with NHL diagnosed and treated between 1975 and 1988. The histopathologic diagnosis was revised in accordance with the working formulation system, three prognostic groups being thus considered: low-grade (LGL), intermediate-grade (IGL) and high-grade (HGL) lymphomas. Age, sex, clinical course prior to diagnosis, presence of B symptoms, histologic type, number of lymph-node areas involved, bulky disease, anaemia, thrombocytopenia, LDH, stage and response to therapy were all evaluated for the study. Survival curves were drawn with the Kaplan-Meier method, and the log-rank test was used for comparison of median survival. Whenever the univariate analysis achieved statistical significance, a multivariate analysis was performed by means of a multiple correlation and regression study in accordance with the Cox's model, in which the variables were expressed in a binary model. The following 8 values were found significant in the univariate study of low-grade lymphomas: age, number of involved areas, bulky disease anaemia, thrombocytopenia, LDH, stage, and initial response to treatment. In intermediate-grade lymphomas, the significant findings were age, number of affected areas, bulky disease, thrombocytopenia, LDH, stage, and initial response. For high-grade lymphomas, number of affected areas, thrombocytopenia, LDH, stage and initial response were found statistically significant. Although no significant differences were found for survival within each of the three grades, such differences were significant between them. In the multivariate analysis, age was significant only in the LGL (p < 0.0001) in IGL, age (p < 0.07) and initial response to therapy (p < 0.0001) achieved significant value, and in HGL, stage (p < 0.02) and initial response to treatment (p < 0.0001) attained significance. The univariate analysis provides various prognostic factors of statistically significance, as reported in the literature, but these after the multivariate analysis was applied, were reduced to age, stage and initial response to treatment.


[Features of chronic myeloid leukemia at diagnosis. Study of a series of 134 cases].

To analyse the clinico-biological features of 134 patients with chronic myelogenous leukaemia (CML) at presentation. The series is comprised of 134 patients from the Asturias Central Hospital and other hospital of the region, diagnosed of CML with conventional criteria between 1970 and 1989. A retrospective study was carried out revising the clinical records and the clinico-biological data at diagnosis. Cytogenetic studies were available in 62 cases. The statistical analysis was based upon descriptive statistics and comparison of means and proportions by the chi square and Student's tests. Univariate study was also performed for several variables. The mean age of the group was 50 years, ranging between 2 and 81. The M/F ratio was 76/58. The commonest symptoms at onset were those secondary to hypermetabolism and splenomegaly, 8% of the patients being asymptomatic. Splenomegaly was present in 73.8% of the patients and hepatomegaly in 37.6%. The median white cell count was 132 x 10(9)/L. Absolute basophilia and eosinophilia were seen in 83% and 78% of the cases, respectively. Anaemia was found in 47.4% of the patients, usually mild, and 39% of them had nucleated red cells in peripheral blood. The median platelet count was 400 x 10(9)/L. Thrombocytosis was found in 48% of the cases, while 11% had thrombocytopenia. The mean number of blast cells in the bone marrow was 1.72%. The histopathologic study of the bone marrow revealed decreased red cells in 94.5% of the patients and decreased megakaryocytes in 29.5%; these last were increased in 50% of the patients. Increased reticulin fibres were found in 38.5% of the bone marrow samples. In addition to the Ph' chromosome, which was present in 51 patients, chromosomal abnormalities were seen in 15.6% of the cases in the chronic phase and in 69.2% in the terminal stages of the disease. Positive correlation could be established between the white cell count and the size of spleen (p < 0.001) and liver (p < 0.05), and there was a negative correlation between white blood cell count and haemoglobin rate and platelet count (p < 0.05 for both). (1) The analysis of this series shows that the CML cases in this region have similar characteristics to those in other western world communities (2). The mean age of this group is somewhat higher than in other series, which should be re-evaluated after discarding the Ph'-negative cases. (3) There seems to be positive correlation between leucocyte count and spleen and liver enlargement, and negative correlation between leucocyte count and haemoglobin and platelet count.


[Cause of death, survival, and prognostic factors in a series of 98 patients with chronic myeloid leukemia].

To analyse the survival from diagnosis to blastic crisis, as well as the causes of death and the significance of different features in patients diagnosed of chronic myelogenous leukaemia (CML). The series includes 98 patients who died of CML in Asturias Central Hospital and other nearby hospital between 1970 and 1990. The CML diagnosis had been established according to conventional criteria. The blastic crisis was diagnosed in accordance with morphologic and cytochemical studies, complemented in some cases with the assay of TdT or other markers. The Kaplan-Meier curves and long-rank test were applied to the statistical analysis of survival. The prognostic factors were evaluated by univariate correlation. The series' mean age was 48.57 years (range: 6-90) and the M/F ratio was 56/42. Cytogenetic study had been performed in 35 patients, of whom 33 had the Ph' chromosome. Death occurred in the blastic crisis in 67 cases (72%), in the accelerated phase in 14 cases (15%) and in the chronic phase in 12 cases (13%). The cause of death could be determined in 47 cases; of them, 24 (51%) died of infection, 11 (23.4%) of haemorrhage, and the remaining 12 (25.6%) of different complications. The median survival of the group as a whole was 32 months (range: 4-137). For the blastic crisis this figure was reduced to 2.5 months (range: 1-14), the lymphoid forms doing better, 5 months, than the non-lymphoid ones; 1.5 months (p < 0.03). Out of the data evaluated at diagnosis, only haemoglobin and the percentage of blast cells in peripheral blood showed any correlation with survival (r = +0.28, p < 0.05 for haemoglobin, and r = -0.30, p < 0.01 for blast cells). (1) Although most patients die from infection or haemorrhage during the blast crisis, CML increases the risk of death in the accelerated and chronic stages as well. (2) Non-lymphoid blastic crisis has poorer prognosis than the lymphoid form. (3) The concentration of blast cells and haemoglobin in peripheral blood at diagnosis acquire prognostic significance in the present study.


[Normal values of hemoglobin, hematocrit, blood coagulation factors, and fibrinolysis in New Zealand white rabbits].

To assess the normal rates of several haematological parameters along with coagulation and fibrinolysis values. Male white New Zealand rabbits weighting between 1.5 and 2.5 kg. were used in variable amounts for each test (117-102). The following haematological determinations were carried out: haemoglobin, haematocrit, platelet count, and peripheral blood cell morphology. Prothrombin time, kaolin-activated partial thromboplastin time and thrombin time were assessed as well. Fibrinogen, plasminogen, prothrombin, factor V, factor X and factor XIII assays were also performed, along with tests for fibrinolytic activity and assay of fibrin and fibrinogen degradation products. All tests were compared with samples of pooled human and rabbit plasma. A statistical study was carried out including mean, mode, standard deviation, variation coefficient, confidence interval and chi square test plus Kolmogorow-Smirnoff test for normality assessment. The curves attained after plotting the figures for haematocrit, haemoglobin, platelet count, kaolin-activated partial thromboplastin time, thrombin time and factors II and X approached the normal values (p > 0.05). Asymmetric curves were achieved for fibrinogen, prothrombin time and plasminogen (p < 0.005). Rabbit anti-fibrinogen serum reacted with rabbit plasma and fibrinogen, but failed to react against human samples. No fibrin and/or fibrinogen degradation products were detected and no fibrinolytic activity was observed on fibrin plate assays. White New Zealand rabbits have values for haemoglobin, haematocrit and fibrinogen similar to the human ones. On the contrary, factors V, X and XIII, along with plasminogen, are in higher concentration, especially the former. Factor II is present at about half the human concentration. No fibrinolytic activity could be demonstrated with the methods used here.


[Effect of physical training on hematological parameters in young swimmers].

To evaluate the effects of a regular training programme on some haematological values in a group of young swimmers. The study group is composed of 32 infantile swimmers (18 boys and 14 girls) and the control group of 12 boys and 11 girls of similar ages, performing no sports. Blood samples were taken at the beginning of training and four months later. Automated blood cell counts were performed in duplicate, along with assessment of the serum levels of iron, ferritin, transferrin and haptoglobin. The statistical study was made by comparison of means (Student's t, Wilcoxon and Mann-Whitney's U tests). Significant descent of haemoglobin rates (p < 0.05) was found in the swimmers, whereas serum iron was also significantly decreased (p < 0.01). Transferrin and haptoglobin were increased in both sexes (p < 0.01) in the swimmers, while ferritin was increased only in the female swimmers. With regard to the control groups, the boys showed significantly higher levels of ferritin both at the beginning and the end of the test, whereas the girls had lower only at the beginning (p < 0.01). After a 4-month physical training programme the tissular iron deposits are increased in a population of infantile swimmers, such increase being significant only in females.


[Stereological study of the fat cells in bone marrows with a heterogeneous distribution of adipose tissue].

1) To analyze to what extent the fat tissue fraction of the human bone marrow with heterogeneous distribution depends on size and number of adipocytes. 2) To infer the influence of local factors on the two aforementioned parameters. The material was made up of 15 specimens of bone marrow biopsy with markedly heterogeneous distribution of fat tissue, alternating normal or hyperplastic zones (area I) with aplastic ones (area II). The method of study was the stereological technique on plastic-embedded specimen sections. In the area II, with a fat tissue fraction markedly higher than in area I, both adipocyte number and size were significatively increased. The fat tissue fraction difference (Dif FRGR) between both areas was significatively correlated with the difference of the adipocytes number (Dif Nv) but not of the size (Dif D). However, in multiple regression both Dif Nv and Dif D contributed significatively to Dif FRGR. Since the histopathological pattern investigated in this work represents a model caused by intervention of local factors, it can be concluded that these can modify both the size and number of adipocytes.


[Treatment with interferon alfa-2a in the chronic phase of Philadelphia-positive chronic myeloid leukemia].

To evaluate the cytologic and cytogenetic response attained with interferon alpha-2a (IFN, Roferon*A) in patients with Ph '-positive chronic myelogenous leukaemia (CML) in the chronic phase. A prospective study was carried out on 22 CML patients diagnosed in the Haematology Service at the Princesa Hospital in Madrid. The therapeutic regime consisted of two phases: A) Hydroxyurea was given until the white-cell count was reduced to 15-20 x 10(9)/L. B) Roferon*A was then given subcutaneously at a doses of 5 MU/m2 per day. The follow-up was performed weekly, and monthly once the leucocyte count had stabilized. The cytologic and cytogenetic response was assessed by bone marrow aspiration performed after 6, 9, 12 and 18 months. The toxicity was evaluated in accordance with the WHO recommendations. The median follow-up is 263 days (21-930). Thirteen patients (65%) had initial complete haematological response and 3 (15%) had partial response. The mean time to achieve response was 42 days (0-321). In the last evaluation, 69% of the patients were in sustained haematological remission (53% complete and 16% partial) with median follow-up of 232 days (21-930). The cytogenetic response was evaluable in 13 patients (follow up > or = 6 months): three attained complete response (23%) and three others partial response (23%). The commonest untoward effects were hypertriglyceridaemia (100%) and myelosuppression (86%). Grade-III thrombocytopenia was seen in 19% of the patients and grade-III anaemia or leucopenia in 5%. No infectious or haemorrhagic complications have appeared. Therapy was discontinued in 3 patients (14%), two due to severe flu-like syndrome and one for parkinsonism after 809 days of treatment. At the moment of evaluation two patients had died, one in lymphoid blastic crisis on day 217 and the other in the immediate post-BMT period. Treatment with interferon-alpha 2A is useful in the chronic phase of CML. An important number of responses can be attained, even in patients in the late chronic phase, and the toxicity seems acceptable.


[Rearrangement of the bcl1 and bcl2 oncogenes in chronic lymphoid leukemia].

Oncogenes bcl1 and bcl2 are located in the rupture site of t(11;14) and t(14; 18), respectively. They have been found to rearrange in different B-cell malignancies. A molecular study of oncogenes bcl1 and bcl2 was carried out in 42 patients diagnosed of B-cell chronic lymphoid leukaemia. In 14.3% of the patients the rearrangement affected bcl1, but no differences were found with regard to stage and clinical course between these patients and those without any oncogen rearrangement. In all the patients studied bc12 was in a germinal configuration.


[Masked Philadelphia chromosome: diagnostic implications in a case of chronic myeloid leukemia presenting in blast crisis].

We present a female patient with acute non-lymphoblastic leukemia (ANLL) and with haematologic features suggestive of its evolution from chronic myeloid leukaemia (CML), in which a bone marrow karyotype showing a "masked" Philadelphia (Ph) chromosome due to a variant translocation of complex type t(9;9;22)(q32;q34;q11) was found. We comment the peculiarities of this special Ph chromosome as well as the differential diagnostic problems between ANLL Ph(+) and CML with onset in blastic crisis.


[Correlation between the grade of histological malignancy and nuclear positivity using the AgNOR technique in 6 cases of isolated bone NHL].

Several reports have shown that the degree of positivity for the AgNOR count can be used to evaluate the aggressiveness of malignancies since it express an increased protein-synthesis activity. This technique was applied to six cases of stage I osseous non-Hodgkin's lymphoma--4 intermediate grade (2 diffuse small, non-cleaved cell and 2 diffuse large, non-cleaved cell lymphomas) and 2 high-grade immunoblastic lymphomas--in order to assess the histologic grade and the number of AgNOR-positive regions. It was noted that survival together with the trend to invade the surrounding soft tissues (i.e., the tumour aggressiveness) correlated with the AgNOR granule count. Both factors were also related with Ki-67 cell-proliferation antibody positivity. Such correlations were even higher than those found with the histologic features conventionally evaluated in the Working Formulation, so they seem to convey more reliable indices of neoplastic growth potential.


[Chronic neutrophilic leukemia associated with myeloma. Simultaneous presentation].

A case of chronic neutrophilic leukaemia associated with multiple myeloma is reported. The patient had a 6 months history of bruising and weight loss, and showed mature neutrophilic leukocytosis, hepatosplenomegaly, high neutrophil alkaline phosphatase score, hyperuricaemia, neutrophils with pseudotoxic granulation and scarce Döhle bodies; moreover, a monoclonal IgG lambda was detected amounting 57.3 g/L. The bone marrow was grossly hypercellular with marked myeloid hyperplasia and aggregates of immature plasma cells. After treatment during 1 year with melphalan and prednisone she is well, although persisting with neutrophilic leukocytosis, slight splenomegaly, and the monoclonal IgG decreased to 25.8 g/L.


[Reduction of iron deposits after physical exercise of short-duration].

To study iron metabolism in young people subjected to short-term physical exertion. Haemoglobin rate, plasma iron, total iron binding capacity and haptoglobin were assessed before, during and fifteen days after seven-day intensive exertions (military drill) in 38 cadets of the General Military Academy at Zaragoza, at sea-level altitude. The type and intensity of the exercises and the diet were similar for all the subjects. Mean and standard deviation of all values were calculated; the differences were studied by paired t test and p < 0.005 was fixed to allow statistical differences. Decreased serum ferritin, which probably means diminished iron deposits, was found after exertions. Haemolysis is not likely involved since the haptoglobin rates were not decreased below the security limits which avoid haemoglobinuria. Physical exercise, although of short duration, may lessen iron deposits, although not to the extent of iron-lack erythropoiesis.


[Second neoplasms as a late complication of the treatment of Hodgkin's disease].

To determine the incidence of a second malignancy in patients with Hodgkin's disease (HD) diagnosed and treated in the same hospital. A retrospective study was performed on 99 patients diagnosed and treated for HD in the Hospital San Carlos, in Madrid, between January 1976 and december 1987. The clinical records were revised; the diagnosis and staging followed the Rye and Ann Arbor criteria, and the treatment included radiation therapy (RT), chemotherapy (CT), or a combination of both. The diagnosis of the second malignancy was based upon clinical, analytical, radiological and histological records. The median age in the series was 31 years (16-82) and the M/F ratio was 61/38. The stage distribution was: I-9; II-29; III-31, and IV-30. Twenty-six patients received RT alone, 59 were treated with CT, and 14 received RT plus CT. A second neoplasm was found in 6 patients (6%), of whom 4 developed a myelodysplastic syndrome (MDS) and 2 a solid tumour. All the patients who had MDS had received MOPP or C-MOPP chemotherapy, associated in two of them with extensive RT. Both patients with solid tumour had been given CT+RT. The median time of presentation of the second malignancy since the diagnosis od HD was 89 months (48-174) for MDS and 120 months for the solid tumours. The four MDS patients have died, 2 for ANLL-M5, one for SRA and the remainder for cerebral haemorrhage, not yet evolved into acute leukaemia. The two patients which solid tumours are alive and seemingly in complete remission at 12 and 10 months, respectively, of the diagnosis of the second malignancy. 1) All the patients with second neoplasms had been previously treated with CT (MOPP or C-MOPP) or CT+RT. 2) Non-Hodgkin's lymphoma has not appeared in any of the patients in this series. 3) An endless follow-up of patients with HD seems important in order to achieve an early diagnosis of other malignant complications which, although in case of MDS have poor prognosis, in case of solid tumours may do well with adequate treatment.


[Disseminated intravascular coagulation induced by endotoxin in rabbits: effect of treatment with t-PA and urokinase].

To assess the therapeutic efficacy of agents capable of stimulating the fibrinolytic system, such as tissue plasminogen activator (t-PA) and urokinase (UK) on endotoxin-induced disseminated intravascular coagulation (DIC) in the rabbit. DIC was induced by intravenous administration of endotoxin, 20 micrograms/kg/hr during 6 hr. Four different groups were established: a) control group, receiving only saline solution; b) t-PA group receiving 0.2 mg/kg; c) t-PA group receiving 0.7 mg/kg, and d) UK group, which was given 3,000 IU/kg/hr for 6 hr. Blood samples were drawn before and after 2 hr and 6 hr of endotoxin administration. Platelet count, and fibrinogen, factor XII and antithrombin III concentrations, were assessed in each sample. Mean, standard deviation and percentage of increase or decrease with respect to the basal value, this considered 100%, were used to evaluate the findings. For comparison of values, Student's t and Mann Whitney's U were used; the Fisher test was used for mortality studies. No statistical differences appeared for any of the values in the rabbits under basal conditions. The rabbits in the control group developed DIC. No doses of t-PA modified the changes appearing in blood coagulation. UK reduced the fibrinogen and factor XII consumption induced by endotoxin. The mortality rate in the control group reached 70%. High-dose t-PA decreased such figure to 50%, while low-dose t-PA or UK failed to reduce mortality. High-dose t-PA has beneficial effects on endotoxin-induced DIC in rabbits. UK failed to achieve such effect at the doses given in this experimental DIC model.


[Acute lymphoblastic leukemias off therapy: course of 80 cases after treatment cessation].

To retrospectively analyse all the patients diagnosed and treated in the same hospital for acute lymphoblastic leukaemia (ALL) in whom therapy was suppressed after sustained complete remission (CR) for a variable period. Eighty cases of ALL treated at the Jiménez Díaz Foundation between 1968 and 1991 were revised. Treatment had been suppressed after 60 months of maintained CR (1968-1974) or after 28 months (1986-1991), with a median follow-up after suppression of 6 years. All the patients had been treated with several protocols (FJD-68, FJD/BFM, APO, BFM-83, BFM-86 and BFM-90). Maintained CR, relapses and course after therapy cessation were analysed. Actuarial curves of RC duration and survival were drawn according to the Cutler and Ederer life tables. The age at diagnosis ranged from 1.5 to 68 years. Childhood (< 15 years) ALL presented in 49 cases; 25 were young adults (15-30 years), and 6 others were over 30 years of age. Two of the 80 patients (2.5%) died in CR (astrocytoma and demyelinating leukoencephalopathy). Fifty-eight patients (72.5%) are living in maintained CR; 20 others relapsed (25%), 14 of them (70%) attaining a second CR. Allogenic BMT was carried out in 4 such cases. Four patients are out of any treatment after the second CR. The actuarial curves of CR duration after suppression of therapy gave a stable plateau at 73% for children, at 75% for young adults and at 22% for patients over 30 years. The survival after suppression of therapy showed a plateau at 75% for children and at 86% for young adults. 1) Relapse was seen in 25% of the patients after cessation of therapy. 2) Relapse occurred in the first two years after therapy cessation in 75% of the instances. 3) At this writing, 78.7% of the patients keep up the CR. 4) Adults over 30 years of age comprise the poorest prognosis. 5) The course of young adults in this series after cessation of therapy is as good as that of children.


[Use of a chromosome 21 gene library in the identification of a marker chromosome in chronic myeloid leukemia].

The non-isotopic in situ hybridization makes it possible the analysis of, both, numeric and structural chromosome aberrations in interphase nuclei. Moreover, this technique is useful for identification of chromosome markers of unknown origin, frequently present in malignant diseases. In our case, the fluorescent in situ hybridization allowed us, in a CML patient in accelerated phase, to know the origin of a chromosome marker, and then, to state that the patient had a 21 trisomy added to the Philadelphia chromosome.


[Hereditary elliptocytosis caused by a spectrin deficiency (Sp alpha I/46). 1st patient described in Cuba].

We report biochemical studies of membrane proteins performed in a patient with hereditary elliptocytosis (HE). The presence of 90% of elliptocytes on wet smears of glutaraldehyde-fixed cells, the increased red cell thermal sensitivity, the normal erythrocyte membrane electrophoresis, the increased spectrin dimer in the 4 degrees C extract (35%) and the 46 Kd peptide present in electrophoresis after limited tryptic digestion of spectrin, allows us to classify this disorder as type I HE. The patient has common HE with compensated mild hemolysis. This is the first case of HE with alpha chain molecular variant of spectrin found in a Cuban population.