Diabeteslike preproliferative retinal changes in galactose-fed dogs.

Retinal vessel changes were experimentally investigated by a combination of color fundus photography, fluorescein angiography, and histologic studies in beagles that were fed a 30% galactose diet for up to 66 months. Previously, we have described the appearance of pericyte ghosts, microaneurysms, acellular capillaries, and intraretinal hemorrhages in dogs fed a galactose diet for up to 36 months. These disorders were similar to those observed in humans with background diabetic retinopathy. We report herein that dogs fed galactose for 48 to 60 months experience retinal changes associated with the chronic occlusion of capillary beds and subsequent ischemia of the retina. These changes included the appearance of broad areas of nonperfusion, soft exudates (cytoid bodies), intraretinal microvascular abnormalities, occluded arterioles, preretinal and intravitreal hemorrhages, and apparent new vessel growth around the optic disc. The present study clearly demonstrates that the galactose-fed dog is an animal model in which advanced retinal changes develop, and these changes are similar to those associated with preproliferative human diabetic retinopathy.


Fundus measurements with indirect ophthalmoscopy. An experimental approach.

We examined the factors influencing the accuracy of indirect ophthalmoscopic estimates of choroidal tumor size by studying indirect ophthalmoscope photographs of solid black domes implanted in the suprachoroidal space of postmortem human eyes. Measurements of the indirect ophthalmoscope photographs showed clinically significant differences in the absolute diameter of the visualized fundus, which varied with differences in condensing lens power and width, anteroposterior location of viewed fundus, and axial length of the experimental eye. Linear regression analysis demonstrated that the field of view of each condensing lens varied similarly with axial length and that the majority of variation in field size for each condensing lens was attributable to axial length variation. Equatorial fields of view averaged 11% smaller than posterior fields of view. The accuracy of estimated absolute intraocular dimensions using indirect ophthalmoscopy potentially approaches +/- 5%.


Tying the knot. Is it always necessary?

Securing the final muscle position during adjustable-suture strabismus surgery is usually accomplished by tying the sutures in a knot in the early postoperative period. Even patients who have satisfactory ocular alignment without adjustment require manipulation of inflamed ocular tissues to secure the muscle. In our experience, approximately half of these cases are not adjusted. We have devised a technique in which postoperative knot tying is required only in those patients who actually undergo adjustment. In our series of 42 patients who underwent adjustable-suture surgery, 22 cases were not adjusted and 30 cases were left untied. No instances of muscle slippage occurred. We believe this reduction in postoperative manipulation represents an improvement in adjustable-suture strabismus surgery.


Lasers in dermatology.

The author gives a resume of the use of the different types of laser in dermatology and outlines the indications and usage for each one. Special emphasis is put on recent changes.


Diagnostic ultrasound.

Significant growth in the technology and clinical application of diagnostic ultrasound has occurred over the past decade. The non cardiac aspects of these recent developments are briefly discussed and illustrated.


Psychotropic medications.

A number of new psychotropic drugs are now available and new uses have been found for old ones. The author highlights these changes.


Operative hysteroscopy and endometrial ablation.

Operative hysteroscopy is often an alternative to hysterectomy in the treatment of menorrhagia. The author describes the techniques involved and explores some of the advantages and disadvantages.


General practice 'going places'.

This paper, which was presented at the Annual General Meeting of the Royal Australian College of General Practitioners in September 1991, outlines possible roles for the general practitioner in the public health system. Four fundamental steps need to be taken: affirmative action by health boards to include GPs in all activities; representation of the RACGP on health boards; adequate remuneration; and part time employment of GPs in all health care delivery service units.


Obstetrics in a small maternity hospital.

This paper presents the case for continuing to practise safe obstetrics in a small suburban hospital. Boothville Maternity Hospital, Brisbane, is a Salvation Army hospital of 20 beds. Seven thousand births during the years 1975 to 1989 are reported. Perinatal mortality rate was 4.9/1000 total births, forceps rate 7.1%, caesarean rate 9.3% and transfer rate to larger centres 1.6% for babies and 1.2% for mothers. Personalised family-centred care in congenial surroundings serves to maximise the factors that favour uncomplicated delivery. Large centralised and small peripheral hospitals should be seen not as competitive but as complementary. Boothville provides mutually satisfying co-operation for care-givers and care-receivers.


General practitioner referrals to a department of emergency medicine.

The aim of this study was to determine the number and content of general practitioner referrals letters and telephone calls in 1000 consecutive patterns and assess the outcome for the referred patients. Communication between GPs and emergency medicine staff was of generally acceptable quality but could be improved in areas of letter content and call back to GPs by emergency medicine staff.


Medical writing. A beginner's guide.

The author presents practical guidelines for writing a variety of medical articles. Newer forms of exposition, for example, poster presentations, are also explored. Guidelines and checklists for common grammatical problems are included.


Trainee research projects.

In this series, items contributed by others with research interests are welcome. This month I summarise a report presented to the 1991 RACGP convention in Hobart by Dr Roger Strasser, Senior Lecturer in Community Medicine at Monash University.


Diarrhoea.

Diarrhoea is defined as the frequent passage of loose or watery stools. Most patients can easily recognise and accurately define acute diarrhoea as an abrupt change in their bowel habits. Chronic or recurrent diarrhoea is more difficult for the patient to define, since it may mean malabsorption, tenesmus or true diarrhoea. Serious disorders not to be missed include neoplasia, AIDS, various serious infections such as amoebiasis, and inflammatory bowel disease.


Squamous cell carcinoma of the skin of the trunk and limbs: the incidence of metastases and their outcome.

The incidence and outcome of metastatic squamous cell carcinoma of the skin is poorly documented. This study, undertaken in a population accessible to long-term follow-up, documents the metastatic aspects of squamous cell carcinoma of the skin of the trunk and limbs. In a review of 695 cases, metastases occurred in 34 cases, with a metastatic rate of 4.9%, an overall mortality of 3.4%, and a 70.6% mortality in the metastatic group. Forty-six per cent of overall mortality was associated with inoperable or recurrent regional disease without evidence of distant metastases. The risk factor associated with the development of metastatic disease were; delayed presentation; large neglected lesions; misdiagnosis; and multiple treatments to the primary lesions. In this series no correlation was found between the histological degree of differentiation of the primary tumour and the development of metastases. The mean latent period between treatment of the primary and the diagnosis of metastases was 11 months. Histopathological review of the regional lymph nodes in the operable group showed that adverse pathology such as multiple nodes, extracapsular spread, vascular and perineural invasion, were associated with regional recurrence and short survival. Twenty-one patients with operable metastases had a mean survival of 53.8 months. This was compared with 13 patients with inoperable disease, in whom the mean survival was 12.2 months (P less than 0.05).


New concepts in radiotherapy for advanced squamous cell carcinoma of the head and neck.

This paper reviews two of the newer concepts - multiple daily fractions of radiotherapy - in improving the treatment of squamous cell carcinoma of the head and neck.


Limitations of radiotherapy in the definitive treatment of squamous carcinoma of the tonsillar fossa.

Between 1970 and 1990, 104 patients with squamous cell carcinoma (SCC) of the tonsil were treated. The median age was 58 years and 80% of patients were males. Distribution among clinical stages was: stage I, 19 patients; stage II, 12 patients; stage III, 23 patients; and stage IV, 48 patients. More than 70% of patients had initial radiotherapy as definitive treatment irrespective of stage, reflecting the treatment philosophy over much of this period. The overall survival rate was 26% at 5 years, with survival being significantly affected by T stage, clinical stage and age. Clinical node status did not significantly affect survival rates. Good local control of T1N0 cancers was achieved with radiotherapy alone, but patients with more advanced cancers did poorly. We have now moved away from a non-selective policy and use initial surgery combined with postoperative radiotherapy in most patients, reserving radiotherapy alone for mainly early tonsil cancers.


Colorectal cancer screening: optimal compliance with postal faecal occult blood test.

Five approaches to postal faecal occult blood test (FOBT) were compared in a population sample of 966 subjects collected from three general practitioner patient lists in Southern Sydney. The highest compliance rate (59.8%) was achieved by a method using a general practitioner letter, with no dietary restrictions with FOBT. This was also the least expensive method. Compliance rates can be affected by incorrect address information and screenees not considering themselves to be current patients. An explanation from the family doctor addressed personally to the patient with an enclosed FOBT kit can achieve high compliance rates.


Inpatient management of piles: a surgical audit.

A retrospective study was performed on 160 patients admitted to the University Surgical Unit between July 1975 and November 1989 with haemorrhoidal disease. Patients' records were analysed with respect to predisposing factors, inpatient management, postoperative analgesia, hospital stay and post-management complications. One hundred and nineteen patients had haemorrhoidectomy (low ligation combined with an anal stretch). Of these, 1.6% developed urinary retention and 4.2% bled postoperatively but did not require surgical intervention. Ten patients were found to have tight anal canals post surgery and required outpatient anal dilatation. In no case was dilatation necessary for more than 3 months. Three patients required a therapeutic course of antibiotics. Of the 119 patients, 60 required narcotic analgesia for less than 24 hours. Hospital stay was 1-4 nights.


Bleeding duodenal ulceration: the results of emergency treatment with highly selective vagotomy.

We report the results of a prospective study of all patients undergoing highly selective vagotomy (HSV) for bleeding duodenal ulceration (BDU) at Concord Hospital between 1979 and 1989. Highly selective vagotomy was undertaken in 63 patients (58 male, 5 female) with a median age of 69 years (range: 16-89). Fifty-five patients were reviewed, 7 patients having died in the peri-operative period and one being lost to follow-up. The mean period to review was 50 months (range: 1-120). Thirty-six patients have been followed-up for more than 24 months. Thirty-day postoperative mortality was 11% (7 patients). Combined major and minor morbidity was 41%. Postoperative rebleeding occurred in four patients (6.3%), three of whom died. Ulceration had recurred in two of 55 patients (4%). Symptoms have been evaluated in 55 patients since operation and 93% have been graded as Visick I or II. We conclude that HSV is effective in the emergency treatment of BDU and has few long-term sequelae.


Changing trends in perforated peptic ulcer during the past 45 years.

Since 1944 there has been a dramatic change in the pattern of admissions for perforated peptic ulcer (PPU) to the Royal Newcastle Hospital, the main teaching hospital of the Hunter Region, Australia. Between 1944 and 1950, females accounted for 6% of all perforations; since then the proportion of females admitted with this complication has risen to 32%. Simultaneously, the modal age for PPU has shifted from the fifth to the seventh decade and the ratio of gastric to pyloroduodenal perforations has fallen from 1.1:1 to 0.6:1. No good explanation for this change in the natural history of PPU, also noted elsewhere, is evident.


Wound closure and suturing patterns: a vector analysis of suture tension.

When the vectors of force required to close the ideal surgical wound are analysed, it is apparent that suture tension varies with the pattern of suture. For a given closing force, perpendicular interrupted sutures have the least tension. Symmetrical continuous sutures require greater suture tension, and this increases the more the suture is aligned with the direction of the wound. Asymmetrical (perpendicular/diagonal) continuous suturing requires more tension than interrupted sutures but this never exceeds 200%. Symmetrical suturing has slightly less tension than asymmetrical suturing when the spacing is about equal to the width of the suture. However, as the spacing ratio increases to greater than 2, the tension in the symmetrical suture rises very sharply. At a length:width ratio of 4, the symmetrical suture tension is about 70% greater than the same asymmetrical suturing.


Ligature versus purse string for surgical stapled anastomoses.

Intraluminal circular stapling in gastrointestinal surgery requires a purse string suture which secures the bowel around the anvil of the head of the stapling gun before firing. An alternative method of securing the bowel around the anvil is described.


Role of the pre-test in the progressive assessment of medical students.

A prospective, randomized, controlled trial was conducted to see if a pre-test, given immediately before teaching, improved performance in a subsequent post-test. The study was also used to assess the educational value of a structured teaching method. Third year medical students were randomized into study and control groups. In phase I, the study group completed a subject-specific multiple choice question (MCQ) pre-test immediately before a teaching demonstration on vascular disorders. The control group completed a placebo pre-test. At the completion of teaching both groups did the same subject-specific post-test. The experiment was repeated in phase II where the groups were crossed over and traumatology was the subject of the demonstration. In both phases of the experiment there were no significant differences between the post-test marks of the experimental and control groups (P = 0.128 and 0.397, respectively). The experimental groups did, however, increase their marks significantly when their post-test results were compared with pre-test marks (P less than or equal to 0.0001, phase I and II). It was concluded that the pre-test did not result in a measurable increase in learning. The study did demonstrate that the teaching method was effective as post-instructional knowledge increased by nearly half when compared with pre-test levels.


Prolonged hepatic ischaemia due to liver injury: a case report.

A case is reported in which a young male who underwent right hepatectomy necessitated by gunshot wound to the liver, survived 2 h 20 min of normothermic hepatic ischaemia. This case extends the documented duration of hepatic ischaemia compatible with survival and documents the histopathology of the post-ischaemic liver.


Constrictive pericarditis associated with trauma and pectus excavatum.

A case of constrictive pericarditis is reported in a 31 year old man with pectus excavatum. The constriction was secondary to an organized traumatic pericardial haematoma immediately behind the pectus deformity.


A bronchogenic cyst causing respiratory distress.

A case is reported of acute respiratory distress in an adult that was caused by a bronchogenic cyst. Bronchogenic cyst in an adult may be seen on chest X-ray and confirmed by computerized tomography (CT) scanning. Surgical excision can provide dramatic relief.


Duplex Doppler ultrasound signs of portal hypertension: relative diagnostic value of examination of paraumbilical vein, portal vein and spleen.

The sonographic parameters in portal hypertension (PHT) were examined in a consecutive population of 118 patients who had PHT diagnosed using specific endoscopic, sonographic and Doppler signs. A patent or enlarged paraumbilical vein was found in 85.6% of patients overall and 82.5% of patients with varices indicating a relatively high sensitivity. A portal vein diameter greater than or equal to 13mm was found in only 41.1% and greater than or equal to 15mm in only 20% of patients. A thrombosed portal vein and reversed portal vein flow were present in 3.4% and 5.3% of patients respectively. These signs have only been reported in the context of PHT and are felt to be specific for PHT, but both have a very low sensitivity. Portal vein velocities were highly variable suggesting that this is not a useful predictor of PHT. Splenomegaly was found in only 53.5% of patients demonstrating its poor sensitivity as a sign of PHT. Varices were found in 73.3% of patients overall, and in 100% of patients with a patent or enlarged paraumbilical vein combined with ascites. No other statistically significant correlation between varices and sonographic findings was demonstrated. We conclude that the presence of a patent or enlarged paraumbilical vein is a practical, useful and sensitive ultrasound sign to look for in the diagnosis of PHT.


Efficacy of fetal part elevation to visualise internal cervical os.

The diagnosis or exclusion of placenta previa is best achieved by direct visualisation of the relationship of the lower edge of the placenta to the internal cervical os. In later pregnancy, the presenting fetal part frequently obscures this area. Elevation of the presenting part was attempted in 56 consecutive pregnancies of greater than 30 weeks gestation, with a success rate of 71%. This confirms that in a minority of pregnancies, other manoeuvres or ultrasound techniques are necessary to visualise the lower placental margin directly.


Percutaneous lung aspiration biopsy: a comparison between two fine needles.

Fine needle lung aspiration biopsy is now a well established method of obtaining tissue for histopathological diagnosis. It is fast, simple and reliable, and has a very low complication rate. We report our experience using two fine needles, the Turner and the EZ-EM Cut-Biopsy needles, comparing their yield and complication rates. We found that both needles had comparable diagnostic yields (65% with the Turner, and 71% with the EZ-EM) and complication rates. We also found that in most cases, aspirates alone were sufficient for diagnosis, and that obtaining tissue cores with larger bore EZ-EM needles did not significantly influence the diagnostic outcome. We conclude that both the Turner and the EZ-EM needles are equally effective and safe in percutaneous lung aspiration biopsy. The least traumatic needle should be used except when the cytological diagnosis is nonspecific inflammatory cells or inadequate, in which case a repeat with a cutting needle is advised to obtain a core of tissue.


An analysis of reported discomfort caused by mammographic X-ray amongst attenders at an Australian pilot breast screening program.

The aims of the study were to describe levels of discomfort experienced by women undergoing screening mammography; examine correlates of discomfort experienced and to examine whether the degree of discomfort experienced was perceived as a deterrent for re-screening. The study involved ninety five attenders at the pilot mammography screening program in Melbourne, Victoria. Women completed a questionnaire one or two days after having a screening mammogram. Pain was assessed on a seven point scale. Information was obtained on a number of possible correlates such as breast tenderness, perceptions of the service received and expectations of discomfort. Eighty-eight women were re-interviewed three months later about recall of discomfort and whether this would deter them from future mammography. Results were as follows: Thirty per cent of women reported no discomfort, 60% mild or moderate discomfort and 10% severe discomfort or worse. The degree of discomfort reported was not significantly related to age, breast tenderness in the previous three days, previous symptoms, previous mammographic experience, or outcome of visit. The degree of discomfort was related to retrospectively reported expectation of discomfort (r = .336; p = .001); reported lack of confidence in the staff taking the X-ray (r = .184; p = .039); perceptions of awkwardness (r = .175; p = .049) and unpleasantness (r = .297; p = .002) of the examination position. No woman said discomfort would definitely stop her having another screening mammogram. Three per cent said that it might stop them, while 97% of women said that it would not stop them at all.(ABSTRACT TRUNCATED AT 250 WORDS)


Breast pain associated with mammographic compression.

Firm breast compression during film-screen mammography is necessary to achieve optimum image quality while minimizing radiation dose. Of 374 women who fully completed a questionnaire following mammography, 225 (60%) reported no pain, 115 (31%) moderate pain and only 3 (1%) reported severe pain. Only one patient stated that the pain from the procedure would prevent her from having a further mammogram. Underlying breast disease (usually fibrocystic disease) is associated with a greater incidence and severity of breast pain, but, no relationship has been demonstrated with regards to the patient's age, hormonal status, menstruation or caffeine intake. The high level of acceptance of firm compression by women in our study indicates that undue concern regarding patient discomfort should not deter people from referral for mammography or from the application of firm compression.


CT evaluation of orbital osseous hemangioma.

Two patients with osseous hemangioma of the orbit, and with typical features on plain radiography and computed tomography, are reported. The typical features of osseous hemangioma of the orbit on computerised tomography (CT) are: expansile bony lesion limited by a thin sclerotic rim, bony trabeculae radiating from the centre to the periphery of the lesion, and absence of an associated extra-tumoral soft tissue mass. To the best of our knowledge this is the first report of osseous hemangioma of the orbit evaluated by CT.


Air in epidural haematomas.

Air in epidural haematoma is an uncommon finding. It is usually seen if epidural haematoma is associated with fracture involving one of the air sinuses, but can be seen at times in the absence of any demonstrable fracture on the CT scan. Seven such cases are described in the present communication and the significance of this finding discussed.


Temporomandibular joint air in fractures of the skull base.

Basilar skull fractures involving the temporal bone extend through the tympanic part of the temporal bone in two-thirds of cases. The anatomical relationship of this part of the temporal bone and the temporomandibular joint enables air to pass from the auditory canal into the joint. Air in the temporomandibular joint is demonstrated on CT scans as an indirect sign of temporal bone fracture.


Anomalous peritoneal folds of the duodenum--a normal variant simulating disease.

The double contrast barium meal appearance of four cases is presented where an anomalous peritoneal fold involves the duodenum. This fold results in a characteristic smooth, extrinsic indentation upon the antero-superior surface of the duodenal cap. This normal variant should be differentiated from distortion of this region due to pathology such as peptic ulceration. Anomalous peritoneal folds which involve the duodenum (cystoduodenal ligament, cysto-gastrocolic ligament) are not believed to cause symptoms (1). However, the recognition of the deformity produced by these folds is important, requiring differentiation from pathological changes.


Dose normalisation and specification: from woe to go.

A questionnaire has been completed by 16 practising Radiation Oncologists from 10 centres in Australia and New Zealand which confirms that considerable variation in dose normalisation and specification practices exists between Australasian centres. The establishment of a working party to determine whether a uniform code of practice (such as ICRU 29 or a modification thereof) is desirable, and can be adopted in Australasia, is recommended.


Anaphylactoid reaction to iopamiro (after pretreatment).

A patient is described with a past history of an anaphylactoid reaction to contrast media who reacted to nonionic contrast media after pretreatment with antihistamines and steroids. The available options to reduce the incidence of reactions include use of non-ionic contrast which has a reported lower frequency than ionic contrast or some form of pretreatment. Various forms of pretreatment have been described and in the majority steroids and antihistamines are used. We describe a patient who reacted to nonionic contrast after a pretreatment regime.


Multifocal osteosarcoma with extensive pleural metastatic disease.

An eighteen year old female presented with multifocal synchronous osteosarcoma, with multiple skeletal foci of tumour in long bones, pelvis and spine. The radiographically dominant lesion was in the right ilium, and this was considered to be the primary site. There was an extensive osseous pleural plaque and there were also metastases to lungs, peritoneum, abdominal wall, adrenal gland and lymph nodes. A review of the literature reveals that multifocal osteosarcoma is an uncommon condition and is probably due to metastatic disease and not multiple primary lesions. Pleural metastatic disease in osteosarcoma has been seldom reported.


Intracerebral ganglioglioma.

A case of a rare intracerebral tumour, namely a ganglioglioma, is reported to illustrate the CT and MRI features. The finding of focal thinning of the inner skull vault in association with an adjacent intracerebral mass lesion can aid in the diagnosis of intracerebral ganglioglioma.


Central neurocytoma.

One case of central neurocytoma is presented. A review of the literature suggests that the condition is more common than previously recognised. The pathological features are discussed and the role of surgery and radiotherapy in the management of the condition is discussed.


Cerebro-costo-mandibular syndrome.

Cerebro-costo-mandibular syndrome (CCM) is a very rare entity with oro-facial features closely resembling Pierre-Robin anomaly (1,2). We describe a patient with typical features: severe micrognathia, glossoptosis, central cleft soft palate and multiple posterior rib-gap defects seen on chest radiograph. Respiratory distress which was evident soon after birth was relieved by an oro-pharyngeal airway. He suffered from a cardiorespiratory arrest and succumbed, presumably secondary to aspiration of milk feeds, before a tracheostomy could be performed.


A case of hepatic hydrothorax due to a large diaphragmatic defect.

Hepatic hydrothorax is an infrequent complication of cirrhosis. The source of pleural fluid has been the subject of considerable speculation. A case of hepatic hydrothorax is discussed which illustrates a large diaphragmatic defect as the cause of ascitic fluid passing into the pleural cavity.


Lymphomatoid granulomatosis.

A case of lymphomatoid granulomatosis is presented demonstrating the most common chest radiograph findings as well as some infrequent but recognized associations. The clinical presentation and pathogenesis are discussed. The difficulty in radiological diagnosis is highlighted.


Adrenal myelolipoma.

A case of adrenal myelolipoma demonstrated by ultrasound and computed tomography is presented with a discussion of the aetiology and review of literature. Ultrasound and CT proved to be invaluable in the pre-operative diagnosis of adrenal myelolipoma.


Thrombolysis and the femorofemoral bypass graft: a new technique.

Two patients with acutely thrombosed femorofemoral bypass grafts are presented. Recombinant human tissue-type plasminogen activator (rt-PA) was used successfully in thrombolysis of the occluded grafts. Utilizing a new technique the grafts were punctured directly and bolus doses of rt-PA administered.


Must macrosomic fetuses be delivered by a caesarean section? A review of outcome for 786 babies greater than or equal to 4,500 g.

Because difficult vaginal delivery is more frequent with macrosomic fetuses, some writers recommend routine Caesarean section for the delivery of fetuses greater than or equal to 4,500 g. The purpose of this study was to evaluate the appropriateness of this recommendation. A retrospective review was undertaken to determine how many fetuses born in our hospital weighing greater than or equal to 4,500 g died or were permanently damaged as a consequence of mechanical difficulties at delivery. During a 10-year period, 590 (75%) of 786 cephalic babies weighing greater than or equal to 4,500 g and alive at the start of labour were born vaginally. No baby died or was permanently damaged as a consequence of mechanical difficulties at delivery. Routine Caesarean section for macrosomic fetuses to prevent death or damage from difficult delivery is not warranted by our results.


Why deliver in the supine position?

This study was conducted at the Lokmanya Tilak Municipal General Hospital, Bombay, India during the year 1990. The aim was to compare the routinely used supine position versus ambulation in the first stage and squatting position during the second stage of labour. Our study was comprised of 200 patients both primigravidas and multigravidas; 100 were kept in the supine position throughout labour and 100 were kept ambulatory in the first stage and adopted the squatting position during the second stage. The study showed a shortening of both stages of labour in the squatting group but the incidence of complications was less in the control group. It was concluded that without proper birthing chairs which can give excellent perineal support, the usual supine position is preferable in our setup.


Antepartum cardiotocographic surveillance of patients with diminished fetal movements.

Over a 9-year period, 2,601 women had antenatal cardiotocography (CTG) performed after reporting diminished fetal movements. This series represented 5.6% of the total hospital population and 16.1% of those having antenatal CTG performed. The perinatal mortality rate (0.8%) and major fetal malformation rate (2.2%) were lower than in the hospital population (1.1% and 4.5% respectively). The incidence of abnormal CTG tracings was lower in the 1,390 women with diminished movements alone (6.4%) compared with the 1,211 who had additional antenatal complications (10.2%, p less than 0.001). Likewise the incidences of critical fetal reserve CTG and perinatal mortality were significantly lower in the group without additional complications (0.3% and 0.5%) compared with those with additional complications (1.7% and 1.2% respectively). The 24 patients with critical fetal reserve CTG were promptly delivered (19 by Caesarean section) with favourable results in 19, cerebral palsy in 1, and 4 perinatal deaths - 2 of these deaths resulted from intrauterine hypoxia (table 3, Cases 12 and 15). There were 17 perinatal deaths in cases where the CTG was satisfactory (13) or showed reduced reserve (4); 9 of these were unavoidable as a result of major malformations or other lethal conditions. The other 8 deaths resulted from hypoxia, including 4 in pregnancies at or beyond 37 weeks' gestation (table 3, Cases 6-9), illustrating that delivery is warranted in women with diminished fetal movements when conditions are favourable even when the CTG is satisfactory. Cardiotocography is useful in the management of patients with diminished fetal movements.


Telephone fetal heart rate monitoring in South Australia.

A pilot trial was conducted to assess the technical feasibility of long range fetal heart monitoring by telephone in an Australian setting. The indications for such monitoring and patient ability and attitude towards self-monitoring was also assessed. One hundred and fifty seven tracings were received from 57 women using a simple doppler device to transmit fetal heart sounds to the central hospital fetal monitor. Thirty three of the patients were in country hospitals and 24 were at home. Gestation ranged from 26 to 42 weeks' gestation. Eighty six percent of the country hospital tracings and 94% of the home tracings were easily interpretable. The large majority of tracings were normal and appeared to encourage conservative management by the attendants. Two tracings were abnormal and these influenced early delivery in both cases. Nearly all women using the monitor at home found the procedure easy and reassuring. Tracings from country hospitals were initiated usually after an acute antenatal complication, whereas the indications for home-monitoring were prompted by longer-term, medium-risk factors. Home-monitoring may reduce the inconvenience and expense of inpatient or outpatient care and country hospitals without electronic fetal monitors may benefit from such a service. The selection of patients who might benefit from such technology remains controversial and warrants a prospective randomized controlled trial.


Temperature drop in normal term newborn infants born at the University Hospital, Kuala Lumpur.

A prospective study of temperature drop in 141 normal term newborn infants delivered vaginally at the labour ward, University Hospital, Kuala Lumpur were studied. The effect of various manoeuvres on the temperature drop were also studied. They were randomized into 3 study groups, 63 cases where the babies were wiped with dry cloth alone, 37 cases where the babies were put into a plastic bag immediately after birth and lastly 41 cases where the babies were wiped with dry cloth and then inserted into a plastic bag. There was significant temperature drop in all the 3 groups maximum in the first 15 minutes and the fall continued for 1 hour after delivery (p less than 0.001). This shows that in an air-conditioned labour ward in a tropical country the temperature fall in newborn infants can be significant. This study also showed that plastic is a poor insulator against significant temperature drop.


Pregnancy outcome following preterm premature rupture of the membranes at less than 26 weeks' gestation.

The outcome of 71 singleton pregnancies where premature rupture of the membranes (PROM) occurred at gestations of less than 26 weeks was assessed retrospectively. The incidence of chorioamnionitis was 39.4% and the overall maternal morbidity rate was 53% but there were no long-term maternal sequelae. The latent period from PROM until delivery ranged from less than 12 hours to 77 days, with 41% of women delivering within 1 week. There was no increased risk of infection with increasing latent period. The perinatal mortality was 66.2% (26.7% stillbirths and 39.4% neonatal deaths). There was a 65% chance of a live baby if PROM occurred between 24-26 weeks but only 5 of 40 fetuses (12.5%) survived if PROM occurred before 24 weeks. The use of antibiotics, tocolytics and steroids in an uncontrolled manner is reported. Overall there is little serious risk to the mother if a conservative approach is adopted but only about one-third of such women will take home a live baby.


The effect of smoking during pregnancy on the incidence of low birth weight among Chinese parturients.

The incidence and effect of smoking in Chinese parturients are not well known. In a retrospective case-controlled study of 213 patients who smoked during pregnancy, it was found that the incidence of low birth-weight was doubled. On average the babies were smaller by 200 g, shorter by 1 cm and the head circumference was smaller by 0.3 cm. These anthropometric deficits may have significant long-term effects. Although the incidence of smoking in Chinese parturients is low (2%), the rising trend in recent years should prompt all physicians to advise expectant mothers to avoid smoking before and during pregnancy.


A case for revising the 'weight gain during pregnancy' guidelines for Australian women.

In 1989, an average weight gain during pregnancy of 14 kg was determined for a sample of 1,253 public patients at the Royal Women's Hospital, Brisbane. This greatly exceeded the weight gain of 10 to 12 kg which was recommended by the hospital and which is based on United States of America (US) data. The finding prompted a comparison of characteristics of Brisbane mothers (weight gain during pregnancy, age, prepregnant weight, height, birth-weight of infant, etc) with the characteristics of mothers in two large US studies. Significant differences were found to exist with Brisbane women being taller, heavier in body mass, more overweight and gaining less weight during pregnancy than the US women. Unexpectedly, the birth-weight of infants was neither more nor less than reported for the American studies. Further studies to gain more information about Australian women during their pregnancies should be undertaken.


Answering MCQs: a study of confidence amongst medical students.

Medical students at the beginning of their obstetrics and gynaecology module were asked to complete a multiple choice question paper from an earlier module. Half the students were asked to answer only those questions where they were certain of the answers. The other half were asked to answer all questions. The mean mark in the second group was 86% higher than that in the first group. A computer programme was written where multiple choice questions were asked in a standard true/false format but instead of a don't know alternative the students were asked to rate their degree of certainty in having answered correctly on a scale of 0 to 100. Five students completed a total of 45 multiple choice question papers (each with 20, 5-part questions) both before and towards the end of their obstetrics and gynaecology module. The mean mark increased by 68.5% over the course of the module reflecting the students' increased knowledge. Their mean certainty level only increased by 50%, suggesting that the students underestimated their newly acquired knowledge.


Invasive squamous cell carcinoma of the vulva: behaviour and results in the light of changing management regimens. A review of clinicohistological features predictive of regional lymph node involvement and local recurrence.

Ninety-nine patients with carcinoma of the vulva were referred to the Gynaecologic Oncology Unit, Royal Brisbane Hospital, over 10 years. Ninety of these patients had a squamous cell carcinoma (SCC). They were assessed by the 1969 FIGO clinical staging. Each stage was related to nodal involvement, size, depth, histological grade, lymphvascular space involvement, perineural permeation and multifocal disease site. The operability rate was 85%. Treatment was individualized in line with recent philosophies for more conservative surgery where appropriate. Mortality was 2.6%. Five-year survival of surgically treated patients was 60.3%; node negative patients 100%, and node positive patients 25.2%. After adjustment for stage and size, the only other independent statistically significant feature was perineural penetration. Local recurrence was more likely with increased stage and size, unclear margins and multifocal involvement. It is important to note that medically unfit patients who had vulvectomy alone and who later developed positive nodes had 100% mortality. This group of patients significantly decreases survival rates, confirming the importance of carrying out inguinofemoral lymphadenectomy at the time of initial surgery. Morbidity was decreased by conservative surgery. Lymphoedema remains the most common chronic complication. No significant difference was shown in local recurrence between different types of surgery, wide excision, hemivulvectomy, simple vulvectomy or radical vulvectomy (22%), confirming the safety of the more conservative approach of recent years.


Free full-thickness vaginal epithelium graft in correction of recurrent genital prolapse.

Recurrence of a cystocele, rectocele or enterocele following a previous vaginal repair procedure can be an awkward problem to correct. This preliminary report suggests a simple yet very effective method of dealing with such defects.


Reproductive performance following sleeve excision anastomosis operation for genital prolapse.

Genital prolapse is a disorder of pelvic support and is one of the most frequent disorders encountered in our gynaecological practice. Our social and cultural background predisposes to this condition to occur at an age which is reported to be earlier than any part of the world. Over a period of 4 years, 1986-1989, 17 cases were studied in whom the Sleeve Excision anastomosis operation was carried out, either at the Lokmanya Tilak Municipal General Hospital, Sion, Bombay, India or in some other hospital. All these patients were either admitted in active labour or as cases of abortions or were being treated for infertility. The incidence of full-term normal vaginal delivery in our study was 66.6% and the incidence of Caesarean section was 8.3%. There was 1 case of posterior wall rupture following previous sleeve excision anastomosis operation. The recurrence rate of prolapse in our series was only 7.7%. The Sleeve excision anastomosis operation has given excellent anatomical and obstetric results in our study and future multicentric trials will be necessary to study its effect on subsequent fertility to arrive at any final conclusion.


The use of the semen analysis in predicting fertility outcome.

The study investigates the use of the various parameters of the semen analysis in predicting the fertility outcome in 82 infertile couples. The sperm density, % progressive motility, % normal morphology were divided into 'normal' and 'abnormal' based on the criteria proposed by WHO. The subsequent cumulative pregnancy rates were then calculated according to this criteria. A life-table method of analysis was used. All female related fertility factors were excluded. With the exception of a sperm density of less than 20 x 10(6) per ml the other parameters showed no significant correlation with the cumulative pregnancy rates at 12 months or 24 months respectively. We concluded that the semen analysis does not predict the probable outcome of the subsequent rates even when female fertility related factors were excluded apart from a sperm density less than 20 x 10(6) per ml.


The use of clearplan home ovulation detection kits in unexplained and male factor infertility.

One hundred and five couples with unexplained infertility and 43 couples whose infertility was thought to be due to reduced sperm motility were recruited. The median duration of infertility was 36 months (range 12-168). Couples were randomly allocated to either using Clearplan home ovulation detection kits for 3 cycles or were advised about the optimal time during their menstrual cycle to achieve a pregnancy. The clinical details of the 2 groups were similar. In couples with unexplained infertility over the study period 10 (20.4%) in the Clearplan group and 9 (16%) in the control group conceived with 58% of pregnancies occurring in the first cycle. In couples with reduced sperm motility, the results were disappointing with only 2 (8%) pregnancies in the Clearplan group and 2 (11.1%) in the controls. Assisted reproduction technology may not be justified as the first line of management in patients with unexplained infertility.


Endometriosis and race.

The pelvic findings of 202 infertile women undergoing diagnostic laparoscopy in Kuala Lumpur, Malaysia were compared to that of 464 infertile women undergoing diagnostic laparoscopy in Aberdeen, United Kingdom. Endometriosis was significantly more common in the women from Kuala Lumpur (51% against 22%, p less than 0.001). There was however no significant difference seen in the severity of the disease (AFS Classification, 1985). These findings confirm our clinical impression that endometriosis is more common in Asian women when compared to Caucasian women.


A comparison of tiaprofenic acid, mefenamic acid and placebo in the treatment of dysmenorrhoea in general practice.

The efficiency and side-effects of tiaprofenic acid, mefenamic acid and placebo were compared in the treatment of primary dysmenorrhoea. The trial was a double-blind prospective randomized 3-way crossover study during 6 successive menstrual cycles following a 2-cycle run-in period and involved 50 women with primary dysmenorrhoea selected from 96 volunteers between 16 and 35 years of age. Overall pain was significantly less (p less than 0.05) on treatment with tiaprofenic acid than on treatment with mefanemic acid, placebo, or the women's usual treatments. Both active treatments were well tolerated but more side-effects were reported during treatment with mefenamic acid.


A case of intrauterine fetal death associated with maternal Campylobacter coli bacteraemia.

Campylobacter species are known to cause infectious abortion in domestic animals. In humans, Campylobacter are an important cause of enteritis, an occasional cause of systemic infection and have had a rare association with abortion and perinatal infection. A case history of spontaneous abortion, at 26 weeks' duration, associated with maternal bacteraemia, due to Campylobacter coli is presented. Transmission, pathogenesis, treatment, and the need for further investigation are discussed.


An unusual case of retrograde ejaculation.

Despite normal seminal analyses obtained for assay by masturbation, persistent negative postcoital tests led to the testing of postejaculatory urine following normal intercourse. This disclosed an unusual problem of retrograde ejaculation occurring only during intercourse. The mechanism for this selective form of retrograde ejaculation is unknown.


Early growth retardation in the first trimester: is it characteristic of the chromosomally abnormal fetus?

There have been recent reports on a small number of cases which suggest that the detection of early growth retardation might allow recognition of the chromosomally abnormal fetus in the first trimester of pregnancy. To amplify these observations, the crown-rump length (CRL) measurements between the 64th and 86th day of menstrual age were determined in (a) 500 control high risk patients in whom a normal karyotype was subsequently demonstrated by chorionic villus sampling (CVS) and (b) 25 chromosomally abnormal fetuses. The data indicate that early growth retardation, as expressed by a small CRL measurement, is not a special characteristic of the chromosomally abnormal fetus in the first trimester of pregnancy. The CRL measurement is therefore not a useful marker or screening test at that time, except perhaps for triploidy. The well documented growth retardation with trisomy 21 and trisomy 18 which has been observed in the second trimester does not begin until after the 12th week of menstrual age.


Amniocentesis and its complications.

This study was conducted in order to evaluate whether the performance of an experienced operator had any significant influence in reducing the incidence of complications in amniocentesis; 1,459 women had amniocentesis performed under ultrasound guidance; 1,324 were performed by experienced operators and 135 cases by less experienced operators. Complications like fetal loss, blood-stained amniotic fluid, culture failure, multiple needle puncture, leaking liquor, fetal trauma and error in results were compared in the 2 groups. This study demonstrated that amniocentesis performed by an experienced operator decreased the various complications associated with amniocentesis.


Hemodynamic responses to seated and supine lower body negative pressure: comparison with +Gz acceleration.

Hemodynamic changes between upright and supine lower body negative pressure (LBNP) to levels of -70 mm Hg were compared in 8 subjects (5 males, 3 females) and correlated with their findings during simulated Shuttle reentry acceleration with a slow onset rate of 0.002 G/s (1,020 s to peak +2 Gz) and during gradual onset exposures (0.03 G/s) to +3 Gz and +4 Gz. Six of the 8 subjects were able to tolerate 2 min at peak +2 Gz, 2-5 min at +3 Gz, and 1-2 min at +4 Gz. Heart rate (HR) at any given level of upright LBNP regularly exceeded supine levels. HR change at -50 mm Hg in upright subjects (+47.7 bpm from 74.1 +/- 1.9 (M +/- S.E.) bpm, control) was 2.6 times greater than in supine subjects (+18.3 bpm from 64.8 +/- 2.8 bpm, control). HR values at -40 mm Hg supine (73.7 +/- 2.6) matched seated upright pre-LBNP control levels (74.1 +/- 1.9 bpm), while values at -70 mm Hg supine (102.5 +/- 4.4 bpm) were not significantly different from those at -40 mm Hg upright (103.1 +/- 4.0 bpm). Peak HR during +3 Gz (145.8 +/- 7.7 bpm) and +4 Gz (152.3 +/- 6.5 bpm) significantly exceeded recorded supine and upright LBNP levels, whereas values at +2 Gz (104.8 +/- 5.5 bpm) closely matched those at -40 mm Hg upright (103.1 +/- 4.0 bpm) and -70 mm Hg supine (102.5 +/- 4.4 bpm). Supine LBNP HR changes in this relatively small group of subjects closely matched those previously reported in the literature.(ABSTRACT TRUNCATED AT 250 WORDS)


Physiologic validation of a short-arm centrifuge for space application.

A short-arm centrifuge (SAC) of 5-6 ft (1.5-1.8 m) radius may be useful in space to measure tolerances to acceleration (G) and to stimulate the cardiovascular system, thereby reducing cardiovascular decompensation that occurs in weightlessness. Relaxed rapid (1G/s onset rate, ROR) and gradual (0.1 G/s onset rate, GOR) G tolerances were measured on seven men using a 5-ft (1.5 m) radius centrifuge and compared with their G tolerances obtained on the 20-ft (6.1 m) radius human-use centrifuge at the Armstrong Laboratory, Brooks AFB, TX. Since the subjects were required to flex their legs to assume a squatting position on the SAC, a similar position was used on the 20 ft (6.1 m) centrifuge called feet up (FU), and compared with normal-seated +Gz tolerances (controls). The subjects tolerated the SAC exposures without any problems. ROR and GOR tolerances were as follows: control, 3.6 G and 4.2 G; FU, 4.5 G and 5.6 G; and SAC, 4.6 G and 6.4 G. We concluded that a 5-ft radius centrifuge can be used to measure G tolerances. The increases in the SAC GOR tolerances over ROR tolerances indicate that the baroreceptors were stimulated by the G, and the SAC exposure would be useful in preventing cardiovascular decompensation in microgravity.


A biomechanical perspective on exercise countermeasures for long term spaceflight.

Many systems of the body undergo adaptation on exposure to hypogravity, with the lower extremity skeleton experiencing considerable mineral loss during relatively short periods of hypogravic exposure. To date, a variety of countermeasures have had limited success in preventing demineralization, though it is now accepted that mechanical deformation is critical for bone homeostasis on Earth. In the present study, three exercises under active consideration for use in the Space Station were compared in 1 G in terms of the peak loads and rates of change of load elicited under the feet. Peak loading rates were in the ratio of 34.7:1.9:1 for running, rowing, and cycling, respectively. With regard to peak foot loads, the corresponding values were in the ratio of 5.3:1:1.2. These results suggest that exercise during spaceflight must be considered from both biomechanical and physiological perspectives if optimal response is to be obtained.


Motion sickness and equilibrium ataxia.

In order to know the relationship between motion sickness and equilibrium ataxia, we performed Graybiel's ataxia test battery on 10 normal subjects: 1) before donning goggles which reversed the optical image horizontally and vertically; 2) while wearing the goggles and walking; and 3) after walking as long as possible up to 90 min. Horizontal reversal of vision resulted in a statistically significant decrease in the score for all the closed-eyes tests and one open-eyes test performed during walking and after walking, respectively. In contrast, walking while wearing vertical reversing goggles produced a significant but very small change for one of the closed-eyes tests alone. The present study indicates that failure to detect spatial orientation, which evokes autonomic nervous symptoms as an alarm sign, produces equilibrium ataxia by impairing the top-down regulation of body balance, and that vertically reversed vision does not impair spatial orientation needed to maintain upright posture or to execute locomotion.


A comparison of the nauseogenic potential of low-frequency vertical versus horizontal linear oscillation.

The aim of this study was to compare the nauseogenic potential of low-frequency linear motion in the Earth-vertical versus the Earth-horizontal plane, delivered through the same Z-axis of the head and body. Twelve subjects were challenged with linear motion (0.3 Hz, 1.8 ms-2 rms) through the same head and body Z-axis in the Earth-vertical (sitting upright) versus horizontal (lying on the back), while either performing a continuous visual search task or with their eyes closed. Each subject completed the four conditions on a Latin square design with sessions spaced 1 week apart at the same time of day. Vertical motion was clearly more provocative than horizontal motion, and nauseogenicity of motion was exacerbated by a visual search task. Motion sickness impaired performance of the search task. Motion Sickness Susceptibility Questionnaire (MSSQ) scores correlated with individual susceptibility to the motion challenge. Mean sickness ratings for vertical motion showed some correspondence with those predicted by mathematical models of motion sickness dose response relationships.


The effects of perceived motion on sound-source lateralization.

Lateralization of dichotic click pairs differing in time of onset was studied under conditions of angular acceleration, optokinetic stimulation, and gaze fixation. Data obtained from 20 subjects with normal hearing indicate poorer left-right judgment performance for small time differences, as well as shifts in subjective simultaneity, for all experimental conditions relative to control conditions. In addition, response times increased for the experimental conditions. The results suggest that real or apparent motion may affect an individual's ability to process one of the major cues for sound-source localization--binaural time difference--under conditions similar to those encountered in vehicular motion.


Effect of simulated air combat maneuvering on muscle glycogen and lactate.

Muscle glycogen and muscle and blood lactate were evaluated before and after a +4.0/7.0 Gz simulated air combat maneuvering (SACM) protocol in the human centrifuge. The subjects were eight healthy males, ages 25-43 years. Muscle glycogen and lactate were determined from biopsies of m. vastus lateralis in six subjects and whole blood lactate was analyzed in finger-tip blood samples from eight subjects. G-tolerance time was 256 +/- 33 s (Mean +/- S.E.M.). The decrease in glycogen concentration averaged 81 +/- 36 mmol.kg-1 dry wt (p = 0.07). The rate of glycogen utilization was low, averaging 0.4 +/- 0.1 mmol.kg-1.s-1. Muscle lactate increased significantly from 28 +/- 2 mmol.kg-1 dry wt pre-SACM to 51 +/- 4 mmol.kg-1 post-SACM. Post-SACM blood lactate was 4.2 +/- 0.3 mmol.L-1. Neither final blood nor muscle lactate values nor the difference between pre- and post-SACM muscle lactate concentrations were related to G-tolerance time. It was concluded that glycogen availability in m. vastus lateralis is not a limiting factor during exposure to headward acceleration of this type and duration. The lactate values, while high, cannot fully explain the muscular fatigue occurring during centrifuge exposures of the type used here. Therefore, the suggestion by others that anaerobic energy metabolism in skeletal muscles is the crucial factor limiting the ability to resist fatigue during exposure SACM is not supported and is likely an oversimplification of a much more complex problem.


The effects of hypoxia on components of the human event-related potential and relationship to reaction time.

This experiment investigated the relationship between the increase in reaction time (RT) caused by hypoxia and the P300, N200, P200 and N100 components of the event-related brain potential. Eight subjects breathed air or a low oxygen mixture (65% arterial oxyhemoglobin saturation) and RT was collected to visually presented stimuli at two levels of stimulus intensity while ERPs were recorded. An hypoxia x stimulus intensity interaction was found for RT, P300 latency and N200 latency. P200 latency and N100 latency were unaffected by hypoxia. These results were interpreted in terms of Additive Factors Method logic to indicate that the preprocessing stage of stimulus evaluation is slowed by hypoxia and that both P300 and N200 index this slowing.


A review of microgravity surgical investigations.

The likelihood of performing a surgical procedure in space will increase as the Soviet Mir space station is expanded and the Space Station Freedom becomes operational. A review of previous research and hardware development, performed mostly in parabolic flight both in the Soviet Union and the U.S., reveals an interest in surgical chambers to prevent cabin atmosphere contamination. Surgical techniques appear to be no more difficult than in a 1-G environment if a restraint system is used. Minimizing the chances of wound infection from the high particle count spacecraft atmosphere is an additional concern. Additional research is necessary to delineate the clinical significance of these problems and to further develop surgical techniques in microgravity.


Compulsive personality traits affecting aeronautical adaptability in a naval aviator: a case report.

This is a case report of a male naval aviator who demonstrated compulsive personality traits which adversely affected the performance of his duties as a pilot trainee, and later, as a naval flight officer. The Diagnostic and Statistical Manual of the American Psychiatric Association (DSM-III-R) uses the term obsessive-compulsive to describe two conditions. A review of terminology is undertaken to present the reader with the distinguishing features of the personality disorder versus the anxiety disorder. The anxiety disorder, obsessive-compulsive disorder, is incompatible with safe performance of aviation duties. Obsessive-compulsive personality, on the other hand, describes a point on a continuum where useful, adaptive compulsive traits may become abnormally exaggerated and maladaptive, thus interfering with the aviator's normal routine, occupational functioning, relationships with others, and aviation safety.


A survey of blood lipid levels of airline pilot applicants.

Cardiovascular disease represents the single largest cause of premature career termination for airline pilots--an entity approximately equal to all other medical causes combined. It is obviously essential to assess risk factors for the development of cardiovascular disease among airline pilots. For that reason, we obtained lipid levels for 14,448 pilot applicants examined during the period from March 1984 through December 1988. Blood lipid levels are well-documented predictors for future cardiovascular diseases. We determined total cholesterol values, high density lipoprotein (HDL) levels, and the cholesterol/HDL ratio for these lipids for our applicant population. We present these data in tabular and graphic form. They suggest a cessation of any increase in blood lipid levels during the fifth decade of life. While the cause is not obvious, there are a number of factors which may play a role in this finding.


Development of a new device to measure local heat exchange by evaporation and convection.

According to the principles of heat and mass transfer, the rate of local heat exchange by convection (C) and local heat loss by evaporation (E) can be estimated if temperature and vapor concentration profiles in the boundary layer are measured. In addition, temperature (Ts) and vapor concentration (rho s) at the surface may be predicted from the measured profiles. On this basis, a new device was developed to measure parabolic profiles by incorporating three relative humidity sensors coupled with thermistors into its probe. It has been evaluated from various tests including human experiments. The results showed that the device, with humidity sensors arranged perpendicular to the surface, could estimate C, E, Ts, and rho s in closer agreement with direct measurements when compared with the conventional gradient method. This confirmed that our method had clear advantages over the conventional gradient method under laminar air flow conditions.


The abstinence violation effect in sex offenders: a reformulation.

It is argued that the central issue in the treatment of sexually aggressive behavior is the tendency to relapse shown by offenders. A model of the relapse process is presented along with what is described as its central feature, the abstinence violation effect (AVE). This construct is critically examined and its shortcomings identified. A brief description of Weiner's attributional theory is provided and this is used to reformulate the AVE. The advantages of the reformulated AVE are described, as are the clinical implications. Suggestions are then made for future research.


Severity of unipolar depression and choice of treatment.

The National Institute of Mental Health (NIMH) Treatment of Depression Collaborative Research Program (Elkin et al., Archives of General Psychiatry, 46, 971-982; 1989) reported treatment-by-severity interactions favouring pharmacotherapy for more depressed outpatients, on a minority of relevant comparisons. The present study reports secondary analyses from a similar, preexisting data set in which treatment-by-severity interactions are systematically investigated with depressed outpatients treated either with nondirective psychotherapy, behaviour therapy, pharmacotherapy, or relaxation/placebo. Despite multiple severity measures and variable severity cut scores, no treatment was differentially effective in improving more severely depressed patients. Also, there was little difference across symptom severity levels in the proportions of recovered patients between treatment groups. Finally, dynamic cluster analysis demonstrated that the proportion of pharmacotherapy nonresponders (20%) did not differ from the proportion of nonresponders in behaviour therapy or placebo groups. It is concluded that this failure to replicate the NIMH trial findings can not be attributed to treatment differences, populations or statistical power. The suggestion that pharmacotherapy be the treatment of choice for more severely depressed outpatients appears to be unjustified on the basis of available evidence.


The hyperventilation provocation test in panic disorder.

Forty-eight patients with DSM-III-R Panic Disorder underwent a hyperventilation provocation Test (HVPT). Twenty-four patients rated the symptoms induced during the HVPT as similar to those occurring during panic attacks in daily life. Contrary to the classical hyperventilation model of panic, no differences were found in respiratory physiology between recognizers and non-recognizers before and during voluntary hyperventilation. Moreover, recognizers and non-recognizers reported comparable levels of panic and hyperventilation symptoms and state anxiety during panic attacks in daily life. Ten of the recognizers also had a panic attack during the HVPT, independent of any differential CO2 alterations. Compared to non-panickers, panickers obtained higher scores for agoraphobia and depression. On the basis of these results, it is concluded that recognizers or panickers do not show a tendency towards hyperventilation, but that reports of severe panic and hyperventilation symptoms are more closely related to the level of anxiety. These results are more consistent with the cognitive model of panic, which emphasizes the patient's tendency to interpret somatic symptoms catastrophically.


Cognitions and courage in the avoidance behavior of acrophobics.

Fifty subjects (29 fearless and 21 fearful) were tested in a potentially acrophobia-inducing situation, and their avoidance behavior and self-reported fear were noted. Subjects also completed various scales intended to measure their fearfulness and thoughts in hypothetical height-phobic, social-phobic and nonphobic situations. Interviews conducted immediately after the behavioral test, evaluated their thinking, fearfulness and tactics designed to deal with any fear they experienced. Analyses indicated that catastrophic thinking is more evident than irrational thinking in height situations and that such thinking was the best predictor of behavior among the measures used. The results are discussed in terms of their relevance for cognitive views of acrophobia and in terms of their relevance for treatment.


Pain-elicited responses and their role in predicting future pain duration and severity.

The first objective of this study was to carry out a prospective investigation of the behavioral and affective responses to headache pain over a 72 hr period. A sample of 74 headache sufferers provided self-reported ratings of affective and behavioral responses as measured by a composite of standardized questionnaires. Highly significant and clinically meaningful levels of both types of responses were found on the headache day. Interestingly, significant levels of behavioral and affective disturbances were also reported 24 hr after pain termination, indicating that responses to pain actually outlasted pain perception by at least 1 day. The second goal of this study was to investigate whether affective or behavioral responses were predictors of future pain intensity, duration or severity. A smaller sample of 25 subjects provided ratings on two sequential headaches. A series of time-lag analyses indicated that, unlike behavioral responses, strong affective responses during a given episode were associated with subsequently longer and more severe headaches. These results suggest that affective pain-elicited responses may be a risk factor for suffering a worse headache during the episode that follows.


Anxiety and the selective processing of emotional information: mediating roles of awareness, trait and state variables, and personal relevance of stimulus materials.

Previous research has established that anxiety patients demonstrate a cognitive bias that selectively favours the processing of threat related information. The current experiment employs a variant of a well established colour naming paradigm to address three issues concerning the nature of this anxiety linked pattern of selective processing. First, by considering non-clinical subjects and employing an experimental design capable of dissociating the influence of state and trait anxiety, the current study addresses the hypothesis that state anxiety elevations will elicit differential patterns of selectivity in high and low trait anxious subjects. Second, by presenting stimulus materials within or outside awareness, the study addresses the hypothesis that these processing biases occur automatically, without requiring the use of consciously mediated strategies. Third, by including both emotionally valenced stimulus materials which are related to, and which are unrelated to, the particular source of stress experienced by the subjects, the experiment addresses the hypothesis that such anxiety linked processing biases will be restricted to materials falling within the domain of current personal concern. The results of the present study clearly demonstrate that these three issues are not independent. Fundamentally different patterns of anxiety linked selective processing were observed when stimuli were presented outside awareness, permitting only automatic cognitive processing, and when stimuli were presented within awareness, permitting the use of consciously mediated strategies. The relative roles played by state and trait variables, and the degree to which these effects were influenced by the personal relevance of the stimulus materials, differed in each case. The implications of these findings for future research in this field are discussed.


Physical symptoms and illness attributions in agoraphobia and panic.

The cognitive model of panic disorder proposes that panic patients interpret physical symptoms in a catastrophic way, thus precipitating panic attacks. This study describes the development of a questionnaire measure designed to assess beliefs about the health implications of various symptoms. Two groups, agoraphobics and normals, were compared on a variety of measures. Agoraphobics showed much higher panic frequency, fear of anxiety, and prevalence of frightening cognitions when anxious, but did not score higher than normals when assessing seriousness of symptoms. The implications of these results are considered.


Thoughts about eating, weight and shape in anorexia nervosa and bulimia nervosa.

Concurrent verbalisation and a self-report questionnaire were used to investigate self-statements in patients with anorexia nervosa, patients with bulimia nervosa, two groups of dieters and non-dieting controls. Thoughts were collected while subjects performed three behavioural tasks, looking at themselves in a full-length mirror, weighing themselves and eating a chocolate covered mint. Both groups of patients had more negative thoughts related to eating, weight and shape than those in the three control groups. In addition, patients with anorexia nervosa showed a greater concern with eating while patients with bulimia nervosa showed a greater concern with weight and appearance. Differences were found between the patients and non-dieting controls using both methods but the self-report questionnaire was less sensitive than concurrent verbalisation to differences between the patients and dieters. Implications of the findings for cognitive-behavioural treatments of the two disorders are discussed.


Pain and fear: a bioinformational perspective on responsivity to imagery.

Cognitive processing of pain and fear information was examined using a methodology based on the bioinformational theory of emotion. Undergraduate volunteers (n = 48) participated in an imagery assessment procedure involving audio presentation of pain, fear, or pain plus fear experimental scripts. Action and neutral scripts were presented as control stimuli. Heart rate and self-reported affective judgements were assessed. Results indicated that pain scripts were rated more negatively, and were associated with feelings of less dominance than the other experimental scripts. Fear scripts elicited greater heart rate acceleration than either pain or pain plus fear scripts. The direction of physiological and verbal response to pain scripts and fear scripts, however, was very similar, differing only in amplitude; greater heart rate response and more negative ratings were manifested relative to action or neutral scripts.


Self report assessment of anxiety: a cross validation of the Lehrer Woolfolk Anxiety Symptom Questionnaire in three populations.

This study was meant to investigate the psychometric properties and clinical utility of the Lehrer Woolfolk Anxiety Symptom Questionnaire (LWASQ), an instrument for assessment of somatic, behavioral and cognitive aspects of anxiety. Confirmatory factor analysis on data from social phobics (n = 108), normal adults (n = 103) and normal adolescents (n = 650) showed that the three original factors were strongly replicated in each sample. The three subscales appeared to have high internal consistency, while data on convergent and divergent validity were satisfactory. In addition, the subscales did very well in discriminating between phobic patients and normals, and were able to detect treatment effects. In the discussion the instrument is compared with other self report measures of anxiety dimensions, like the Cognitive Somatic Anxiety Questionnaire (CSAQ) and the Worry-Emotionality Scale (WES). It is suggested that similar questionnaires, adjusted to the separate anxiety disorders, should be developed.


Juvenile sex offenders: similar to, or different from, other incarcerated delinquent offenders?

The purpose of the present study was to compare incarcerated juvenile sex offenders to incarcerated youth who committed confrontational but nonsex offenses, and to those youth who committed only nonconfrontational, nonsex offenses. Furthermore, comparisons were made between two subtypes of sex offenders: those youth convicted for rape or sodomy vs those convicted for child molestation. Eighty-three male juvenile delinquents served as participants. Teachers within the correctional facility completed an instrument which allowed the examination of the two areas of interest: externalizing problems and internalizing problems. The results indicated that sex offenders generally, and particularly those who had committed only sex offenses, were perceived as having fewer externalizing and internalizing problems. No differences emerged between the two subtypes of sex offenders. Implications, as well as limitations, of the findings are discussed.


Suicide attempts among juvenile delinquents; the contribution of mental health factors.

This study examined which, if any, of four variables (depression, hopelessness, conduct problems, substance abuse) differentiated suicide attemptors from nonattemptors among incarcerated juvenile delinquents. Fifty-one male youth served as subjects. The predictor variables were collected by either a standardized interview or an orally administered questionnaire. Youth self-report data regarding suicide attempts were collected. The results indicated that depression served as a predictor of suicide attempts but only in white, not black, youth. Suicide attempts also were reported three times more often in white than black participants. Implication, as well as limitations, of the findings are discussed.


Pathways to spider phobia.

Using a revised version of the Phobic Origin Questionnaire (POQ; Ost, L. G. & Hugdahl, K. Behaviour Research and Therapy, 19, 439-477; 1981), the present study examined whether conditioning experiences, modeling experiences, and/or informational learning experiences were more often reported by spider phobics (n = 41) than by non-fearful controls (n = 30). The two groups did not differ with regard to the overall frequency of conditioning or modeling events. Remarkably, the frequency of informational learning was higher among non-fearful Ss than among phobics. Although the limitations inherent to the retrospective nature of the present study should be borne in mind, the data suggest that, at least in spider phobics, conditioning events, modeling experiences, and/or informational learning do not necessarily give rise to phobic fears.


Do drop-outs differ from successfully treated obsessive-compulsives?

The most common reasons given by patients for dropping out of treatment are: environmental constraints, dissatisfaction with services and that they no longer need help. In this study two groups of patients suffering from obsessive-compulsive disorders are compared. The drop-outs' reasons for terminating treatment are compared with the comments of patients who completed the therapy successfully. Drop-outs differ from successfully treated OCD's in five respects: they appear to be less obsessive-compulsive; they have more discongruent treatment expectations; they are more critical of the therapist; they experience less anxiety in carrying out homework assignments; they less frequently come under pressure from people close to them.


One-trial backward excitatory fear conditioning transfers across contexts.

One path to human phobia may be one-trial backward fear conditioning. Human phobias transfer readily across contexts. However, animal studies of one-trial backward fear conditioning have yet to demonstrate such transfer. The present study sought to do so. It used a lick-suppression procedure with 84 naive male albino rats. Two conditioning contexts, designated O and V, were crossed factorially with two test contexts, O and V. Within each cell of the factorial design, rats received in the conditioning context either a single 12 sec tone backward paired with a single 4 sec 1 mA shock or the same tone explicitly unpaired with shock. Fear of context and fear of tone were subsequently assessed in terms of the suppression of licking that they evoked. Test results suggested that (1) the rats discriminated between contexts O and V, and (2) despite such discrimination, one-trial backward fear conditioning transferred across the two contexts. The results enhance the plausibility of one-trial backward fear conditioning as a source of human phobia.


State and trait differences in depressive self-perceptions.

A number of investigators have interpreted a tendency for depressed people to recall more negative than positive self-referent adjectives as evidence for a depressive self-schema made up of predominantly negative characterological information. We sought to confirm this account by eliciting the subjective self-perceptions of the depressed. Depressed patients and controls were required to rate whether or not a series of positive and negative adjectives applied to them during the previous week, at any time, and generally. The depressed distinguished clearly between these questions and, although describing themselves currently in largely negative terms, described their general state as equally composed of positive and negative elements.


The effects of masturbatory reconditioning with nonfamilial child molesters.

Abel and Annon's (Reducing deviant sexual arousal through satisfaction, Denver, Colo., 1982) suggested combination of 'directed masturbation' and 'satiation' to alter deviant sexual preferences, was applied to 10 nonfamilial child molesters. Post-treatment assessments revealed significant reductions in deviant arousal as was expected, but unfortunately there were also reductions in appropriate arousal although these changes did not achieve statistical significance. The results are discussed in terms of their meaning but it is concluded that empirical support for these clinically popular procedures remains weak.


Frequency-dependent action of antiarrhythmic drugs: the useful concept of periodical ligand binding.

The action of most antiarrhythmic drugs which block cardiac ionic channels depends on heart rate, which is established as use- or frequency-dependence. This property is consistent with periodical drug (ligand) binding to channel binding sites which are transiently available during the excitation sequence of cardiac tissue. Antiarrhythmic drugs differ with respect to their binding and unbinding kinetics, i.e., with respect to their blocking and unblocking kinetics. This gives rise to different block-frequency relations and onset-kinetics of frequency-dependent ion channel blockade. Antiarrhythmic drugs have never been systematically compared with regard to their block-frequency relations. However, both the onset-kinetics as well as the block-frequency relation are essential in characterizing the frequency-dependent drug action, since both may be predictors of the anti- and pro-arrhythmic potential of antiarrhythmic drugs.


Three-dimensional analysis of regional mechanical function, blood flow and electrophysiological parameters during early myocardial ischemia in dogs.

Ventricular arrhythmias are primarily responsible for sudden cardiac death early after the onset of acute myocardial ischemia. We designed an experimental model to simultaneously characterize regional myocardial function, myocardial blood flow, and electrophysiological parameters, and to determine predisposing factors for the development of early ventricular arrhythmias (EVA). The left circumflex coronary artery was occluded in six anesthetized (n = 2 piritramide/N2O, n = 4 chloralose/urethane) mongrel dogs. Systolic wall thickening (%WT) in a control zone and in the central ischemic zone was measured with sonomicrometry and regional myocardial blood flow (RMBF) with colored microspheres. Excitability and relative refractory period at the stimulus electrode and conduction times to all other electrodes were determined with a three-dimensional transmural multi(16)-electrode assay using a computer algorithm. In three of six dogs spontaneous EVA occurred 4 to 6 min after coronary occlusion, degenerating to ventricular fibrillation in two of these dogs. The three dogs developing EVA were not distinguished from those not developing EVA, neither by the kind of anesthesia nor by ischemic % WT (-6.6 +/- 3.8 [SD] vs -7.8 +/- 1.6, ns). Also, dogs with and without EVA did not differ significantly in excitability and relative refractory period. In contrast, dogs with EVA were characterized by a greater mass of severely ischemic myocardium, i.e., exhibiting a RMBF reduction to less than 0.1 ml/(min.g) (18 +/- 3 g vs 7 +/- 4 g, p less than 0.05), and by an increase in subendocardial conduction times of greater than 100% above the respective pre-ischemic values (120 +/- 18% vs 66 +/- 9%, p less than 0.05). Dogs with and without EVA were not as clearly distinguished by the increases in subepicardial (81 +/- 22% vs 46 +/- 15%, ns) and transmural (98 +/- 31% vs 67 +/- 14%, ns) conduction times. The development of EVA is associated with a greater mass of severely ischemic myocardium and a greater increase in subendocardial conduction times.


Identification of two distinct amplifications of the esterase B locus in Culex pipiens (L.) mosquitoes from Mediterranean countries.

Two new highly active esterases were detected by starch electrophoretic studies in Culex pipiens mosquitoes from the area of Montpellier (France) and from Cyprus. We demonstrate here that both the French and the Cyprus esterases B are overproduced due to amplification of the coding gene. The production of the esterase B is approximately 50- and 500-fold higher in mosquitoes from France and Cyprus, respectively, than in susceptible insects, whereas the number of gene copies is about 25 and 250. Differences of about 7- and 95-fold were also found in the degree of chlorpyrifos resistance. RFLP comparison of the amplified region containing the esterase B gene revealed large differences between French and Cyprus mosquitoes. It thus appears that two distinct haplotypes with an esterase B gene coding an enzyme with identical electrophoretic mobility have been amplified. We therefore named the haplotypes in mosquitoes from France and Cyprus B4 and B5, respectively. The estimated genetic distance between these two haplotypes is not smaller than those observed in all pair comparisons of other known esterase B haplotypes. These results are discussed in the context of amplification phenomena.


Evidence for a genetic duplication involving alcohol dehydrogenase genes in Ceratitis capitata.

An Adh duplication is described in the medfly Ceratitis capitata. Evidence is presented for two separate Adh1 and Adh2 structural loci mapping at a distance of 0.49 recombination unit from each other. By deletion mapping the Adh region has been cytologically located near the free end of the left arm of the second chromosome within an area between 2C;3A segments of the polytene chromosome. The genetic analysis of the region around Adh has identified seven neighboring genes (Acon1, Mpi, Est6, Aox, Xdh, Mdh2, Lsp1) which identify the linkage group D. The orientation of loci with regard to the centromere sets the origin of the map of the left arm of the second chromosome close to the two Adh loci.


Role of cellular defense against hydrogen peroxide-induced inhibition of myocyte respiration.

Hydrogen peroxide (H2O2) serves as a precursor for highly reactive oxygen intermediates. However, the respiratory function of myocytes is relatively resistant to exogenously administered H2O2. In this study, we examined whether or not the reduction of cellular defense increases the toxicity of H2O2. Rat heart myocytes were isolated by collagenase digestion. Respiratory rates of myocytes, suspended in a medium containing sucrose, 3-N-morpholino-propanesulfonic acid, EGTA and bovine serum albumin, were determined polarographically in the presence of pyruvate and malate with or without 2,4-dinitrophenol (DNP). Mitochondrial membrane potentials were measured by using [3H]triphenylmethylphosphonium+. Cellular defense was attenuated by i) inhibiting the catalase activity by 3-amino-1,2,4-triazole (AT), ii) reducing the glutathione concentration by diethyl maleate (DEM) or ethacrinic acid (EA), and iii) permeabilizing the sarcolemmal membrane by saponin. The dose-response relationship between H2O2 (0.1-5 mM) and mitochondrial membrane potential was not greatly affected by these experimental conditions. Myocyte respiration was inhibited by 5 mM H2O2, particularly that measured in the presence of DNP (48% of control). DEM treatment did not significantly affect the respiratory inhibition by H2O2, whereas the degree of inhibition was somewhat greater following EA or AT treatment. By contrast, the sensitivity of cellular respiration to H2O2 was potentiated approximately two orders of magnitude by the permeabilization of sarcolemmal membrane; thus, 100 microM H2O2 inhibited both DNP-stimulated and unstimulated respiration to 17% and 35% of control, respectively. The results indicate that factors existing in the sarcolemma and/or in the cytosol, which become ineffective and/or are diluted, respectively, following permeabilization with saponin, are important cellular defense mechanisms in alleviating the toxic effect of exogenous H2O2 on the respiration of mitochondria in situ in myocytes.


Characterization of two electrophoretic lactate dehydrogenase-A mutants in Mus musculus.

Two lactate dehydrogenase (LDH) mutations were recovered independently among offspring of ethylnitrosourea-treated male mice by screening for alterations of isoelectric focusing pattern in liver homogenates. Investigations of physicochemical and kinetic properties of the mutant enzymes indicated that the mutant traits resulted from point mutations at the Ldh-1 structural locus. Therefore, the new alleles were designated Ldh-1a-m5Neu and Ldh-1a-m6Neu, respectively. Both mutant alleles code for proteins which exhibit an altered stability to heat, in addition to changes in isoelectric focusing pattern and a reduction in anodal electrophoretic mobility. While LDH-Aa-m5Neu proteins are markedly less heat stable, LDH-Aa-m6Neu proteins are more heat stable than the wild-type enzyme. Furthermore, a small elevation of Km for pyruvate, a slightly reduced inhibition by high pyruvate concentrations, and a slight acidic shift of the pH activity profile distinguish LDH-Aa-m6Neu from both wild-type and LDH-Aa-m5Neu enzymes. Significant alterations of LDH activity were detected in some tissues from LDH-Aa-m5Neu individuals but not in those from LDH-Aa-m6Neu animals. Erythrocytes and blood of LDH-Aa-m5Neu mutants revealed activity levels which were reduced by approximately 6 and 13% compared with those of wild types in heterozygous and homozygous individuals, respectively. In addition, an elevation of approximately 6% in LDH activity was found in skeletal muscle in homozygous mutants. Consistent with the unaltered or only slightly altered LDH activity in tissues, the genetic as well as the physiological characterization yielded no easily detectable effects from either mutation on metabolism or fitness of the affected individuals.


Coronary autoregulation and optimal myocardial oxygen utilization.

The complex relationship among myocardial contractility, preload, afterload, and coronary autoregulation was studied using both analytical and numerical methods. To study autoregulation and coronary reserve changes in response to changes in cardiac oxygen consumption and in arterial pressure generation, a new variable was introduced: myocardial resistance to oxygen flow (RO2). This variable was defined as the ratio of the coronary driving pressure to left-ventricular oxygen uptake. High values for this variable indicate small consumption relative to the generated aortic pressure. Conditions which produce the highest obtainable value for RO2 are considered as optimal. An expression relating RO2 to ventricular hemodynamic variables was developed and studied using a mathematical model of the cardiovascular system. The model included a mechanism of local autoregulation based on the assumption that, in steady state, the amount of oxygen consumed equals the amount extracted from coronary blood. Heart rate, peripheral resistance, end-diastolic volume, and myocardial contractility were varied while the coronary circulation was adjusted to meet ventricular oxygen consumption at each state. The model predicts that, for each state of the circulation, there is an optimal level of cardiac contractility for which the coronary reserve is maximized.


Allopurinol-enhanced myocardial protection does not involve xanthine oxidase inhibition or purine salvage.

Isolated working rat hearts were subjected to aerobic perfusion (25 min), cardioplegic infusion (3 min), global ischemia (30 min at 37 degrees C) and reperfusion (35 min). Measurements of myocardial xanthine oxidase and dehydrogenase activity, together with various adenine nucleotides and metabolites, were made at defined stages of the protocol (n = 6/group). Allopurinol pretreatment (20 mg/kg body wt/day for 3 days) improved the postischemic recovery of cardiac function; thus, aortic flow (a representative index) recovered to 68.8 +/- 4.2% compared with 53.2 +/- 2.3% in untreated controls (p less than 0.05). In fresh tissue, allopurinol pretreatment inhibited xanthine dehydrogenase activity by 73.1% (from 11.9 +/- 0.5 to 3.2 +/- 0.8 mIU/g wet wt: p less than 0.05) and xanthine oxidase activity by 95.2% (from 8.3 +/- 1.2 to 0.4 +/- 0.2 mIU/g wet wt: p less than 0.05); however, this inhibition was not maintained during perfusion. During reperfusion, myocardial xanthine dehydrogenase and oxidase activity was reduced by 40-60% (p less than 0.05) in both allopurinol pretreated and control hearts. Tissue content of creatine phosphate, adenosine triphosphate and catabolites, NAD and inorganic phosphate were not different in allopurinol pretreated or control hearts during either ischemia or reperfusion. This study does not support the concept that allopurinol protects the rat heart during ischemia and reperfusion by inhibition of xanthine oxidase activity or by conservation of purines. It appears that allopurinol achieves its protective effects by some, as yet undefined, mechanism.


Drosophila acetylcholinesterase: characterization of different mutants resistant to insecticides.

Selection of field populations originating from several countries allowed us to isolate 13 strains of Drosophila melanogaster resistant to parathion. In vitro studies of acetylcholinesterase inhibition by paraoxon have been carried out on purified enzymes: most of the resistant strains harbor an altered acetylcholinesterase. Enzymes with higher resistance levels have been characterized with respect to their cross-resistance toward several insecticides. The patterns obtained have permitted us to group them and to delineate four categories. The existence of four distinct types of protein suggests that several mutations of acetylcholinesterase are responsible for insecticide resistance in Drosophila.


Duplication of the structural gene for glucosephosphate isomerase and phosphogluconate dehydrogenase in Scabiosa columbaria and their phylogenetic implications in the dipsacaceae.

Zymograms of glucosephosphate isomerase (GPI) and phosphogluconate dehydrogenase (PGD) revealed three isozymes for each enzyme in the plant species Scabiosa columbaria. Intergenic heterodimers are formed between the polypeptides coded by Gpi-1 and Gpi-2 and between those coded by Pgd-1 and Pgd-2, indicating that a GPI and a PGD locus have been duplicated in the past. The ancestral genes assort independently with their duplicated gene, suggesting that the duplications have originated from a process of translocation. Linkage was found only between Gpi-1 and Pgd-2 and between Gpi-2 and Pgd-1, suggesting that the duplicated loci were located on the same translocated chromosomal segment. Both duplications are present in all other examined species of Scabiosa and in Cephalaria and Knautia, two other genera of the Dipsacaceae. The genera Succisa and Dipsacus, also belonging to the Dipsacaceae, do not show Gpi-1 activity, making Gpi-2 and Pgd-1 the most likely ancestral genes. In Succisa, the isozymes of Gpi-1 and Gpi-2 either overlap or Gpi-1 has been silenced. The combined results suggest that a chromosomal segment containing Gpi-2 and Pgd-1 has been translocated before the divergence of Scabiosa, Cephalaria, Knautia, and Succisa.


Exogenous fructose-1,6-bisphosphate is a metabolizable substrate for the isolated normoxic rat heart.

Isolated rat hearts were perfused by the recirculating Langendorff mode under normoxic conditions for 60 min. The Krebs-Ringer buffer was supplemented with 10 mM glucose + 12 IU/l insulin and either [U-14C]-fructose-1,6-bisphosphate (together with 5 mM cold fructose-1,6-bisphosphate) or [U-14C]-fructose (together with 5 mM cold fructose). At the end of perfusion, gaseous 14CO2, 14CO2 trapped in the perfusates, 14C-lactate output and tissue 14C-lactate were assayed in both groups of hearts. Analysis of high-energy compounds, glycogen, lactate, and pyruvate was also performed on the neutralized perchloric acid extracts of the freeze-clamped hearts. Data obtained from the 14C catabolites, originating from the metabolism of the radiolabeled substrates, indicated that the isolated normoxic rat heart metabolizes an 8.5 times higher amount of fructose-1,6-bisphosphate (7.07 mumoles/min/g d.w.) than of fructose (0.83 mumoles/min/g d.w.). CrP, CrP/Cr, glycogen, and total lactate in both tissue and perfusate were significantly higher in fructose-1,6-bisphosphate-perfused hearts. The overall indication is that fructose-1,6-bisphosphate can be taken up in its intact form by myocytes and successively metabolized to support their energy demand, and that its effects on myocardial performance and metabolism should be attributed to the molecule itself rather than to its eventual degradation products.


Some ribosome-inactivating proteins depurinate ribosomal RNA at multiple sites.

Saporin-S6, a ribosome-inactivating protein (RIP) from Saponaria officinalis released more than 1 mol of adenine/mol of ribosomes from house fly (Musca domestica) larvae and from rat liver. The release of adenine from rat liver ribosomes by several RIPs (plant enzymes with RNA N-glycosidase activity) was examined. Saporins, pokeweed antiviral protein from roots of Phytolacca americana (PAP-R), and trichokirin from Trichosanthes kirilowii seeds depurinated rat liver ribosomes at more than one site. Up to 33 mol of adenine were released from 1 mol of ribosomes. This property is not common to all RIPS.


L-tryptophan uptake by segment-specific membrane vesicles from the proximal tubule of rabbit kidney.

1. The mechanism of the renal transport of L-tryptophan by basolateral and luminal membrane vesicles prepared from either the pars convoluta or the pars recta of the rabbit proximal tubule was studied. The uptake of L-tryptophan by basolateral membrane vesicles from the pars convoluta was found to be an Na(+)-dependent transport event. The Na(+)-conditional influx of the amino acid was stimulated in the presence of an inwardly directed H+ gradient. Lowering the pH without an H+ gradient had no effect, indicating that L-tryptophan is co-transported with H+. 3. On the other hand, no transient accumulation of L-tryptophan was observed in the presence or absence of Na+ in basolateral membrane vesicles from the pars recta. 4. In luminal membrane vesicles from the pars recta, the transient Na(+)-dependent accumulation of L-tryptophan occurred via a dual transport system. In addition, an inwardly directed H+ gradient could drive the uphill transport of L-tryptophan into these vesicles in both the presence and the absence of an Na+ gradient. 5. By contrast, the uptake of L-tryptophan by luminal membrane vesicles from the pars convoluta was a strictly Na(+)-dependent and electrogenic transport process, mediated by a single transport component. 6. Investigation of the coupling ratio in luminal membrane vesicles suggested that 1 Na+:1 L-tryptophan are co-transported in the pars convoluta. In the pars recta, examination of the stoichiometry indicated that approx. 1 H+ and 2 Na+ (high affinity) or 1 Na+ (low affinity) are involved in the uptake of L-tryptophan.