Changes in nitrergic innervation of defunctionalized rat colon after diversion colostomy.

After 45 days of complete diversion colostomy in male Wistar rats, morphometry of soma and nuclei of NADPH diaphorase positive cells of the myenteric plexus was evaluated. There was a significant (P < 0.0001) diminution in the area, perimeter and volume-weighted mean volume of soma and nuclei of nitrergic myenteric neurones in the defunctionalized colon. In addition, there was a significant reduction in the neuronal density of the myenteric neurones, and increased distance between the ganglia. In addition, there was myenteric glial atrophy. Atrophy of colonic myenteric neurones was accompanied by significant reduction (P < 0.001) in the volume fraction of the muscularis externa, the prime targets of these neurones. The disturbances in the microecology of the colon may jeopardize the finely orchestrated functioning of the components of the Enteric nervous system (ENS) leading to colonic dysfunction. Our observations, by extrapolation, may explain the bowel dysmotility in humans after restoration of colonic continuity after colostomy.

Effects of gestational nicotine exposure on hippocampal morphology.

Morphology of the dentate gyrus and Ammon's horn of the hippocampus was observed postnatally in Wistar rats exposed to prenatal nicotine. Pregnant Wistar rats were injected with nicotine (2.5 mg/kg/ day) from gestational day (GD) 6 to term and pups were delivered at term normally. The brains of nicotine-exposed pups at postnatal day (PND) 40 were dissected and processed for araldite embedding. Semithin (0.5 microm) toluidine blue-stained sections of the dentate gyrus, CA3, and CA1 regions of the hippocampus were studied for morphological details. Morphometric analysis showed a significant reduction in the neuronal area of nicotine-exposed brains in all three regions studied. Distal dendritic arbor was significantly less and spine density was more in the granule cells, terminal and basal dendrites of the pyramidal neurons of CA3 and CA1 regions of the hippocampus in the experimental group. CA3 pyramidal neurons showed significantly less apical dendritic thorny excrescence after gestational nicotine exposure. Ultrastructurally the granule cells and the pyramidal neurons of the CA3 and CA1 regions showed increase in free ribosomes and dilatation of rough endoplasmic reticulum (RER) and Golgi apparatus cisternae in the nicotine-treated group. The morphological changes in the hippocampus following prenatal nicotine exposure, as observed in the present study, may contribute to the behavioural abnormalities.

Morphogenesis of the human external male genitalia.

The morphogenesis of the external genitalia of human fetuses (16-250 mm crown-rump [CR] length, 6-26 weeks of gestation) obtained after medical termination of pregnancy were studied. Differential development (male/female) started after 50 mm CR length (9 weeks). At that time the external genitalia consisted of a cylindrical genital tubercle 2 mm in length with a visible coronary sulcus and glans and genital swellings on either side. A groove on the ventral aspect of the genital tubercle extended to the coronary sulcus; the lateral boundaries of this groove separated to form the urethral folds. In male fetuses the free edges of the urethral folds fused, starting from the proximal end, to form a tunnel over the ventral aspect of the phallus. The pelvic urethra opened into this tunnel, slightly distal to its origin. The mesodermal tissue forming the genital swellings migrated ventrally and then medially. As medial migration started, the skin in the midline between the genital swellings was raised up as a skin fold, which subsequently, as the genital swellings migrated further, became elevated. The proximal part of the tunnel formed by fusion of the urethral folds (proximal to the point of entry of the pelvic urethra) also was compressed and pushed out as the genital swellings fused in the midline over the root of the phallus. These changes took place at between 80 and 110 mm CR length (12-13 weeks' gestation); at this stage the phallus appeared short and was bent ventrally. With further growth and caudal migration of the scrotum, the phallus lost its ventral curvature. The appearance of the external genitalia at different gestational ages bore a close resemblance to that in children with hypospadias. We therefore conclude that hypospadias can be explained on the basis of an embryological arrest due to the absence of the required stimulus for male phenotypic development at the appropriate time.

Human female phenotypic development: role of fetal ovaries.

Morphogenesis of external genitalia was studied in human fetuses obtained from cases of medical termination of pregnancies and cases of spontaneous abortions. Eighty-two fetuses, 16 mm crown rump (CR) length (6 weeks gestation) to 240 mm CR length (26 weeks gestation), were studied. Fetal sex was determined with the help of chorionic villus of fetal skin biopsies in cases of fetuses less than 70 mm CR length. Growth and differentiation up to 50 mm CR length (9 weeks gestation) was identical for both sexes. After this there was rapid growth and differentiation in males. But in females subsequent growth until 180-200 mm CR-length stage (20 weeks gestation), was restricted to growth of labia majora. After this there was rapid ventral outgrowth of the region of perineum between the clitoris and anus, which brought the urethral and vaginal orifices to the surface. There was also further growth of labia. This process of feminization of external genitalia was completed by the 26th week of gestation. Histology revealed that ovary and testes could be clearly identified at 60 mm CR length stage. Maturation of fetal testes progressed rapidly, but there was little change in the histological appearance of ovaries until 160-180 mm CR-length stage (18-20 weeks of gestation). Follicular growth started after this. Feminization of urogenital sinus started after follicular growth started in the fetal ovaries. So from the temporal profile of events, it appears that it may be initiated by fetal ovarian steroids.

Effects of prenatal nicotine exposure on the morphogenesis of somatosensory cortex.

Human reports as well as animal studies have recorded accelerated motor activity, learning, and memory deficits in offsprings of mothers exposed to nicotine during pregnancy. Morphological correlation of these neurobehavioural defects has not been done to date. Here, the cerebral cortex has been evaluated after prenatal nicotine exposure. Groups of pregnant rats were injected IP with nicotine at 2.5 mg/kg/day dosage from gestational day (GD) 6 to term. Morphology of the somatosensory cortex was analysed and compared with that of the control group up to postnatal day (PND) 40. A significant reduction in body weight and brain weight on PND 10 and 20, respectively was observed in nicotine exposed group as compared to age matched controls. Morphometric analysis of the somatosensory cortex showed a reduction in cortical thickness up to PND 20 and decreased cell size at PND 10, 20, and 40 in nicotine-exposed brains. Neuronal density of Layer 5 of somatosensory cortex was greater at PND 20 and 40 in the experimental group. Golgi staining of large pyramidal neurons of Layer 5 showed significantly decreased dendritic branching and increased dendritic spine density in the experimental group at all ages studied. Irregular arrangement of cisternae of rough endoplasmic reticulum, paucity of free ribosomes, and frequent cytoplasmic vacuoles were noted by electron microscopy in many neurons up to PND 40. A large number of electron dense cells were observed in nicotine exposed brains at all the time intervals studied. The morphological features of somatosensory cortex observed after prenatal nicotine administration suggest that the drug delays neuronal maturation and affects intracytoplasmic membrane systems.

Emergence of Vibrio cholerae serogroup 0139 in Haryana in May-June 1993.

In an outbreak of acute watery diarrhoea, 11 strains of V. cholerae were isolated in May-June 1993 at Medical College, Rohtak. Eight of these belonged to serogroup Ogawa and three were identified as V. cholerae serogroup 0139. This is the first report of isolation of this novel serotype from this region.

Incidence of mycoses in bronchopulmonary disorders.

A total of 274 samples were collected--180 sputum samples, 82 bronchial secretions and 12 pleural aspirates. Main fungus was Candida albicans from sputum (45.5 percent), from bronchial secretions (14.6 percent). Rest were Aspergillus, Alternaria and Helminthosporium. All the pleural aspirates were negative for fungus.

Vaginitis in non pregnant women in Haryana.

Study was carried out in 100 patients of non-specific vaginitis (NSV) to find out the incidence of vaginitis due to G. vaginalis. Out of a total of 100 subjects 20 were positive for G. vaginalis as compared to only 6 in equal number of normal matched controls. One positive specimen showed concomitant presence of C. albicans and E. coli was found in another positive specimen. Presence of amines and clue cells in the discharge did not correlate with the isolation rate of G. vaginalis, thus emphasizing the necessity of culture to diagnose NSV due to G. vaginalis.

Multidrug-resistant Salmonella typhi in Haryana in 1989-90.

Of a total of 730 strains of S. typhi isolated in 1989-90, in the Medical College Hospital, Rohtak (India), 218 isolates showed resistance to chloramphenicol, ampicillin and cotrimoxazole. Minimum inhibitory concentration (MIC) for ampicillin and cotrimoxazole was up to 3200 micrograms/ml, intermediate for chloramphenicol (200-800 micrograms/ml) and low for tetracycline (50-400 micrograms/ml). A significant observation was prevalence of E1 as the predominant phage type amongst resistant strains accounting for 88.8 per cent of the resistant isolates, 95.8 per cent of these showed block resistance to ACCoT.

Quantitation of early myocardial ischemia using acridine orange fluorescence--an experimental study.

It has been observed in the present investigation that ischemic myocardium consistently produces bright green fluorescence after Acridine Orange (AO) staining. The area of ischemia in the left ventricular myocardium at different time intervals after onset of experimental ischemia has been calculated by use of this AO fluorescence technique. Zonal distribution of ischemia in the epicardial, middle, and endocardial zones has also been evaluated quantitatively from ten minutes to six hours after ligation of the anterior descending branch of the left coronary artery in the Wistar strain of albino rats. No similar study was available for comparison from the literature reviewed. The total area of left ventricular ischemia showed an increase with the prolongation of duration of coronary ligation from 13.39 +/- 2.69 mm2 at ten to twenty-five minutes to 32.99 +/- 5.69 mm2 at six hours after ligation. Statistical analysis of the zonal area of ischemia has shown that ischemia in the middle and endocardial zones was greater than that in the epicardial zone at all time intervals recorded. Middle zone ischemia extended over a larger area than that over the endocardial zone at all intervals except at intervals II (30-45 min), IV (2-2 1/2 hrs) and V (3-4 hrs). The results of this experimental investigation are significant for these point to the value of Acridine Orange fluorescence in detecting early myocardial ischemia and in demarcating zonal differences in ischemia. The authors have successfully utilized the method in a few human cases of clinically suspected myocardial infarction and recommend the technique for routine use to detect early human myocardial ischemia.

T and B lymphocytes in patients with enteric fever.

Estimation of T and B lymphocytes was done in 50 patients of enteric fever, 50 duration matched non enteric fever patients and 50 normal healthy individuals. The difference in both early and late rosette forming T lymphocytes was found to be statistically significant in enteric versus non-enteric patients. Significant difference was also observed in enteric versus normal individuals in case of late rosette forming T lymphocytes.

Resistotyping as a new epidemiological marker for Klebsiella pneumoniae.

Resistogram typing was established with the help of 30 randomly chosen clinical isolates of K. pneumoniae using sodium arsenate, malachite green, boric acid, potassium tellurite, mercuric chloride, antimony potassium tartarate and sodium arsenite. The resistance to these chemicals was designated as A, B, C, D, E, F and G respectively. The technique was then applied to 152 clinical isolates of K. pneumoniae. A total of 35 patterns were obtained. Common patterns were ABEFG and ABFG. There was no clustering of the strains in any of the resistogram patterns as even the commonest pattern had only 10.5 per cent of the strains. When combined with klebocin typing, it provided better discrimination of strains as strains belonging to seven klebocin types could be subdivided into 68 resistogram patterns. The reverse was also possible, i.e., the strains belonging to seven resistogram patterns could be subdivided into 38 klebocin types. The former procedure thus offered better discrimination of the strains.

Association of R plasmids of Klebsiella pneumoniae with resistance to heavy metals, klebocin and beta lactamase production and lactose fermentation.

One hundred and fifty clinical isolates of Klebsiella pneumoniae were studied for beta lactamase production, Klebocin production and resistance to antibiotics and metals. 97.3 and 82.7 per cent strains produced beta-lactamase and klebocin respectively. Resistance to arsenite, antimony, tellurite, mercury and silver was observed in 91,66,6, 47.7, 44.8 and 33.3 per cent respectively and to ampicillin, tetracycline and nalidixic acid in 93.3,60, 41.3, 34.4, 28.2, and 1.3 per cent respectively. Forty eight antibiotic and metal resistant strains were then conjugated with Escherichia coli 711 F-Lac-Nxr. Transferable drug resistance, metal ion resistance, beta lactamase production, klebocin production and lactose fermentation was seen in 30, 21, 10, 11 and 5 isolates respectively.

Histochemical and fluorescent techniques for detection of early myocardial ischemia following experimental coronary artery occlusion: a comparative and quantitative study.

Several workers have used histochemical, enzymatic, and fluorescent methods to diagnose early myocardial ischemia, but the problem of unequivocal detection of early ischemia still remains an enigma to pathologists. In the present study, the left coronary artery was ligated in an animal model, rat, in order to produce myocardial ischemia at different time intervals, from five minutes to six hours. Fluorescent techniques and tetrazolium staining of myocardial succinic dehydrogenases have been used to detect onset of ischemia with the purpose of identifying a sensitive technique for use in routine pathologic specimens. Nitroso-blue tetrazolium and triphenyl tetrazolium chloride staining of myocardium showed loss of dehydrogenases within five to twenty minutes of ligation of the coronary artery. This loss was consistent and progressively increased at longer time intervals, the mean ischemic area mapped being 25.74 mm2 and 66.87 mm2 at five to twenty minutes and six hours respectively. Such comparison of ischemic area of myocardium at different time intervals has not been reported earlier. Autofluorescence in formalin-fixed, hematoxylin and eosin-stained sections showed positive fluorescence only after fifty to seventy-five minutes of ischemia and was patchy in distribution in the left ventricular wall even up to six hours of ligation. Examination of myocardium under fluorescent light after acridine orange staining proved to be more sensitive than autofluorescence for detecting ischemia. At five to twenty minutes, the mean ischemic area was 18.67 mm2 and by six hours it increased to 27.48 mm2.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunohistochemical localisation of neuron-binding antibodies in rheumatic heart disease.

Neuron-binding antibodies and heart-reactive antibodies (HRA) have been investigated in the sera of patients with acute rheumatic fever (ARF) and chronic valvular rheumatic heart disease (both active and inactive by means of immunoperoxidase technique. The incidence of neuron-binding antibodies was highest in ARF (61.1%) in comparison with 54.2% in active chronic valvular disease with activity and 21.1% in inactive chronic valvular disease. In active chronic valvular disease the labelling of neurons was commoner than labelling of myofibres (p less than 0.01). In the other two groups (ARF and inactive chronic valvular disease) no difference in staining of neurons and myofibres was observed. Morphological localisation of binding sites of antibodies in the caudate nucleus neurons showed a definite pattern, which varied from a peripheral crescentic to a diffuse staining within the neuronal cytoplasm, often extending into the dendritic processes. Antibodies binding to caudate nucleus neurons were significantly commoner in ARF and active chronic valvular disease than in inactive chronic valvular disease (p less than 0.05).