Biomedical subjects
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A rare cyanotic heart disease surviving to adulthood with minimal symptoms is presented. The final diagnosis was hypoplastic right ventricle with mild pulmonary stenosis, where the latter was not responsible for the right-to-left shunting across a large atrial septal defect. The differences from cases reported in the literature are highlighted.
The report describes a rare case of a complex congenital heart disease wherein the splenic status and the relationship of the suprarenal abdominal great vessels strongly suggested right isomerism, but atrial morphology demonstrated usual atrial arrangement. It emphasises the increasing recognition that the arrangement of the abdominal organs need not accurately reflect atrial arrangement.
Patients with disabling, persistent somatization pose significant challenges in clinical management. This study describes 92 patients treated on an inpatient psychosomatic medicine unit for persistent somatization. The most important factor in defining clinically significant subgroups of these patients was mood. Compared with depressed somatizing patients, nondepressed somatizing patients had chronic illnesses of early onset, had symptoms that were not correlated with current life stressors, and were generally unresponsive to treatment. There were few clinical predictors of treatment outcome apart from the duration of symptoms, the presence of mood disturbance, and a history of stable interpersonal relationships.
There has been a dramatic increase in age at marriage for women in a rural area of north India. Age at marriage rose from under 12 years before 1930 to about 19 years in 1988, mainly as a result of socioeconomic development and advances in education of women.
Neuroendocrine carcinoma of the skin is an uncommon neoplasm. A case of one such tumour in the head and neck region is being presented. This case is the youngest known patient. The literature has been reviewed. The current concepts in diagnosis and management of this tumour are discussed.
A murine monoclonal antibody which reacts to 22 and 41 kDa Toxoplasma gondii surface antigens was employed in an IgM capture enzyme-linked immunosorbent assay (ELISA). A total of 125 patients' sera were tested in the monoclonal-based assay. When compared with a commercial ELISA test (Abbott Toxo-M EIA) which uses polyclonal anti-T. gondii antibodies, good correlation (Pearsons coefficient r = 0.91) was observed. The specificity of the assay was studied by testing a panel of control sera obtained from healthy individuals and blood transfusion donors; all sera gave negative results. Serum samples positive for T. gondii antibodies were treated with 2-mercaptoethanol (2-ME) to demonstrate the specificity of the test for IgM antibodies. Reactivity of these sera was lost after the treatment. The test is not subject to interference by rheumatoid factor as sera positive for rheumatoid factor were negative in the assay. Reproducibility was good with the coefficients of variation for within-day tests below 10% and not exceeding 18% for day-to-day tests. The monoclonal-based assay is simple to perform and appears to be a viable test for diagnosis of T. gondii infection.
The objective of the work reported in this paper was to determine if the tumorigenic response to 1-methyl-1-nitrosourea (MNU) in the mammary gland varied with age of administration and was dose dependent when the carcinogen was injected prior to 50 days of age. Using a recently developed method for mammary tumor induction, MNU was injected i.p. at doses ranging from 25 to 75 mg/kg at 35 days of age or 50 mg/kg at 28, 35 or 42 days of age. Treatment with MNU resulted in induction of both benign and malignant mammary tumors. The incidence of mammary gland adenocarcinomas was 100% at and above the 50 mg/kg dose of MNU, irrespective of the age at which carcinogen was administered. The number of cancers increased in proportion to carcinogen dose, whereas cancer latency decreased as the MNU dose increased. In rats injected with 50 mg MNU/kg body weight at 28, 35 or 42 days of age, differences among groups in cancer incidence, number or latency were not statistically significant. Metastases of mammary neoplasms to lung, liver and spleen were observed in rats injected with MNU at 35 or 42 days of age. These data indicate (i) the dose responsiveness of MNU-induced mammary carcinogenesis in rats initiated prior to 50 days of age; (ii) the lack of effect of age at initiation if prior to 50 days on final tumor outcome; and (iii) that the age at which MNU is injected may affect the metastatic potential of the mammary carcinomas that are induced.
This study was undertaken to assess the spectrum of drug resistance prevalent in Escherichia coli isolates from human and animal populations in Northern India. Three hundred and two isolates of Escherichia coli isolated from various infections of humans (47 from diarrhoea; 101 from urinary tract infection) and veterinary animals (17 from poultry septicaemia; 75 from bovine diarrhoea; 14 from ovine diarrhoea and 48 from equine metritis) were studied for their susceptibility to ampicillin, cephaloridine, amoxycillin, cloxacillin, oxytetracycline, doxycycline, chloramphenicol, gentamicin, and trimethoprim-sulphamethoxazole. 63.2% of the isolates (37.7%, human; 25.5%, animal) were resistant to one or more drugs, of which about 41% isolates were multiresistant. Resistant isolates had a wide range of MIC values from 12 to 3200 mg/L, irrespective of origin. Most of the isolates (43.5%) were resistant to ampicillin (MIC greater than 16 mg/L) followed by oxytetracycline (MIC greater than 5 mg/L) (36.4%). Only 9.3% isolates were resistant to trimethoprim-sulphamethoxazole (MIC greater than 21 mg/L). The E. coli isolated from animals tended to be resistant to fewer antibiotics than those isolated from man. 99% of the isolates from human urinary tract infection were resistant compared to only 48.9% of the isolates from diarrhoea. Most of the resistant isolates from animals were recovered from diarrhoea, followed by septicaemia and metritis. This study shows that a high frequency of multiresistant strains are prevalent in both human and animal bacterial populations of Northern India. Since the exchange of these strains among both populations is possible, they pose a great risk in both the selection and the spread of resistance.
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The gastric residual (GR) volume was measured in 50 healthy preterm babies, 38 appropriate-for-dates (AFD), and 12 small-for-dates (SFD) with gestational age of 28-36 weeks. The mean basal 4-hour gastric residual (B4 GR) volume was 2.8 +/- 0.63 ml in parenterally fed babies. There was a marked decrease in the residuals from 20.7 +/- 15.2 per cent (mean +/- SD) on day 4 to 8.6 +/- 4.3 per cent on day 7 (P < 0.001). Of the 27 infants fed with expressed breastmilk (EBM), mean GR was 24.4 +/- 10.2 per cent in supine and 12.8 +/- 4.3 per cent in prone position (P < 0.01). Twenty-one babies nursed in the prone position showed a mean GR volume of 12.8 +/- 4.3 per cent with EBM and 13.6 +/- 2.7 per cent with milk formula. No difference was noted in the gastric residuals of AFD v. SFD babies. No linear correlation was found between increase in abdominal girth and GR. However, if the increase in abdominal girth was at least 2 cm or more, a GR of 23 per cent or more was observed. This should be taken as warnings to reduce or withhold oral feeds.
A six month old female infant with pyoderma gangrenosum is reported. Pyoderma gangrenosum in an infant is rare. The child responded to pulse therapy with intravenous dexamethasone and intralesional triamcinolone acetonide.
The management of a preterm neonate with systemic candidiasis using oral itraconazole is described. Oral itraconazole was well tolerated and effected a clinical and mycological cure.
Earlier studies from our laboratory have shown that treatments with gonadal steroids which cause a surge of luteinizing hormone (LH) blunt the effects of morphine on LH secretion, locomotor activity, nociception and temperature regulation. The present study was conducted to determine if the growth hormone (GH) response to morphine sulfate (MS) was also affected during steroid-induced LH surges. Adult ovariectomized female rats were primed with estradiol benzoate (EB: -49 h prior to P4 or oil injection) and/or progesterone (P4; 10.00 h). Seven and one half hours after P4 treatment, at the time of the steroid-induced LH surge, the GH response to an intravenous dose of 0.5, 2.0 or 5.0 mg/kg MS was determined. A GH peak response occurred at 15 min after drug administration and was maximal at the dose of 2 mg/kg MS in all groups. Although the timing of the GH rise was not altered in either EB/oil- or EB/P4-treated animals, a significant blunting of MS-induced GH secretion was observed across all doses of MS with a greater reduction being observed in EB/P4-treated animals. In a second study the GH response to opiates was investigated prior to and following the steroid-induced LH surge to determine if the suppression of opiate-induced GH secretion was confined to the time of the preovulatory LH surge. Before the LH surge (2.5 h), a mild suppression of opiate-induced GH secretion was observed only in EB/oil-treated animals. After the LH surge (13 h after P4 administration), morphine-induced GH secretion was similar in all groups.(ABSTRACT TRUNCATED AT 250 WORDS)
Previous studies have indicated that during the estradiol- and progesterone (P4)-induced surge in luteinizing hormone (LH), the effects of opiates on behavioral, autonomic and neuroendocrine functions are altered. In the present study, we further evaluated the apparent universality of alterations in opiate-mediated function during the LH surge by investigating the effects of morphine sulfate (MS) on prolactin (PRL) secretion during both the estradiol benzoate (EB) and the EB + P4-induced LH surges. All doses of MS tested (0.5, 2.0 and 5.0 mg/kg) resulted in significant increases in PRL secretion in nonestrogen-treated animals which did not show LH/PRL surges. During the LH/PRL surge induced by EB/P4 treatment, MS caused no change in the PRL secretion, while in EB/oil treated animals, a paradoxical and dose-dependent decrease in PRL secretion was observed. The suppression of PRL was 52, 68 and 80% of baseline respectively for the 3 doses of MS. Evaluation of the time dependence of MS on PRL secretion showed that the paradoxical suppression in EB/oil-treated animals was seen only during the LH/PRL surge, occurring at 17.30 h (7.5 h post P4 injection), and not before (12.30 h) or after (23.00 h) the steroid-induced LH/PRL surge. Finally, we assessed the role of pituitary dopamine receptors on the phenomenon of MS-induced PRL suppression in EB/oil rats. Domperidone (1mg/kg), a peripherally active D2 receptor antagonist, administered prior to the morphine challenge, attenuated the opiate-induced PRL suppression in EB/oil-treated animals suggesting that a dopaminergic mechanism is involved in this paradoxical response to morphine.(ABSTRACT TRUNCATED AT 250 WORDS)
In rats fed control and ethanol-containing Lieber-DeCarli diets for a period of 12 months, the bile did not contain any enterokinase, the pancreatic juice did not contain any plasmin or thrombin, but in animals fed high fat diet with ethanol, trypsinogen and chymotrypsinogen were significantly increased and trypsin inhibitor decreased. In the tissue, free trypsin and cathepsin B were increased. Composite profile of trypsinogen in gel segments obtained from the pancreatic juice and the tissue showed higher peaks of cationic and anionic variants of trypsinogen in animals fed ethanol. There was no evidence of mesotrypsinogen or of enzyme Y in the juice or the tissue. These studies show that serine proteases and cathepsin B may play a major role in the pathobiology of alcoholic pancreatitis.
115 newly diagnosed patients with Ta-T1, G1-G2 superficial transitional cell carcinoma of the bladder underwent four quadrant biopsies of normal-looking bladder mucosa, in addition to the endoscopic treatment of the primary tumour or tumours. In 88 (77%) patients all the biopsies were normal; in the other 27 (23%) at least one biopsy revealed dysplasia or carcinoma in situ or G1-G2 carcinoma. 88 patients presented with a single tumour, of which 14 (16%) had abnormal biopsies compared to 13 (48%) of the 27 presenting with multiple tumours. The difference between the 2 groups was statistically significant (p < 0.01). The incidence of freedom from new tumours at 5 years was 68% in patients with normal biopsies compared to 33% in patients with abnormal biopsies (p = 0.002). In patients presenting with multiple tumours and in those with single tumours and abnormal biopsies, the incidence of freedom from new tumours was significantly lower than in those presenting with single tumours and normal mucosal biopsies (p = 0.002). The study shows that the exercise of performing random mucosal biopsies is particularly useful in patients presenting with single tumours, in order to identify those who are more likely to develop new tumours over the longer term. Such patients could be offered early prophylactic intravesical chemotherapy. The study did not substantiate tumour implantation as a factor for new tumour development in superficial bladder cancer.
To study the immunokinetics of equine herpesvirus 1 (EHV1), donkey mares were immunised with a laboratory strain of EHV1, or with recommended doses of Pneumabort-K vaccine (EHV1 Army 183 strain, formalin-inactivated, with an oil adjuvant) and a booster was given after three months. Humoral immune responses were studied by employing a virus neutralisation (VN) test. A leucocyte migration inhibition test (LMIT) was employed for the assay of cellular immune responses. The VN antibody titre reached 1:64 or 1:128 after primary immunisation and showed a marginal increase (1:256) after secondary immunisation with either of the immunogens. After the primary dose of immunogen, there was a gradual increase in host cellular response which persisted for up to three months. However, on secondary immunisation, cell-mediated immune response was short-lived and weak compared to the primary response with both immunogens. This could be one possible explanation for breakdown of anti-EHV1 immunity leading to abortion in immunised mares.
The sensitivity of baroreceptor reflex during myocardial ischemia induced by acute occlusion of left anterior descending coronary artery (LAD) was studied in anesthetized, artificially ventilated, and thoracotomized dogs. Occlusion of LAD attenuated the baroreflex mediated changes in heart rate (HR) in response to changes in arterial pressure (AP) in the animals with intact autonomic nervous system (ANS). The HR increased significantly with the time of occlusion of LAD in control (ANS) as well as in beta-blocked group, suggesting vagal inhibition. In atropinized and vagotomized animals, the HR remained unchanged following LAD occlusion. In control group, the sensitivity of baroreflex mediated tachycardia response to hypotension and bradycardia response to hypertension, after 4 h of LAD occlusion, was reduced. In beta-blocked animals, the tachycardia response after LAD occlusion was drastically reduced to almost zero. The peak sensitivity of baroreflex bradycardia response was reduced in atropinized and vagotomized animals while the peak sensitivity of baroreflex tachycardia response increased after vagotomy. In contrast, bradycardia response was increased after beta-blockade. These data indicate that acute LAD occlusion attenuates arterial baroreflex control of HR and reduction of baroreflex sensitivity is mediated by parasympathetic efferents.