The relevance of a staging laparotomy for Hodgkin's disease in India.

A retrospective analysis of 328 cases of Hodgkin's Disease (HD) subjected to a staging laparotomy at the Tata Memorial Hospital, Bombay, India, from 1974 to 1986 was undertaken to assess its relevance to our setup. Eighty percent of the patients were from clinical stages (CS) I and II, 38% with lymphocyte predominance (LP), and 41% with mixed cellularity (MC) histologies. Staging laparotomy was positive in 60% cases overall, including 50% from CS IA and IIA, 68% from CS IB and IIB, and 53% and 67%, respectively, from LP and MC histologies. Splenic involvement was seen in 54% cases. Operative complications were encountered in 2% of cases and deaths in two cases only. In view of the high propensity for abdominal spread, only selected CS IA and IIA cases would merit a staging laparotomy within which, nearly 50% cases with a negative yield could be offered radical segmental irradiation alone for cure. The majority of our patients would, however, require combination therapy.     

Immunohistochemistry of the canine vomeronasal organ

The canine's olfactory acuity is legendary, but neither its main olfactory system nor its vomeronasal system has been described in much detail. We used immunohistochemistry on paraffin-embedded sections of male and female adult dog vomeronasal organ (VNO) to characterize the expression of proteins known to be expressed in the VNO of several other mammals. Basal cell bodies were more apparent in each section than in rodent VNO and expressed immunoreactivity to anticytokeratin and antiepidermal growth factor receptor antibodies. The thin layer of neurone cell bodies in the sensory epithelium and axon fascicles in the lamina propria expressed immunoreactivity to neurone cell adhesion molecule, neurone-specific beta tubulin and protein gene product 9.5. Some neurones expressed growth-associated protein 43 (GAP43): and a number of those also expressed neurone-specific beta tubulin-immunoreactivity. Some axon fascicles were double labelled for those two proteins. The G-protein alpha subunits Gi and Go, involved in the signal transduction pathway, showed immunoreactivity in the sensory cell layer. Our results demonstrate that the canine vomeronasal organ contains a population of cells that expresses several neuronal markers. Furthermore, GAP43 immunoreactivity suggests that the sensory epithelium is neurogenic in adult dogs.     

Immunohistochemistry of the canine vomeronasal organ

The canine's olfactory acuity is legendary, but neither its main olfactory system nor its vomeronasal system has been described in much detail. We used immunohistochemistry on paraffin-embedded sections of male and female adult dog vomeronasal organ (VNO) to characterize the expression of proteins known to be expressed in the VNO of several other mammals. Basal cell bodies were more apparent in each section than in rodent VNO and expressed immunoreactivity to anticytokeratin and antiepidermal growth factor receptor antibodies. The thin layer of neurone cell bodies in the sensory epithelium and axon fascicles in the lamina propria expressed immunoreactivity to neurone cell adhesion molecule, neurone-specific beta tubulin and protein gene product 9.5. Some neurones expressed growth-associated protein 43 (GAP43): and a number of those also expressed neurone-specific beta tubulin-immunoreactivity. Some axon fascicles were double labelled for those two proteins. The G-protein alpha subunits Gi and Go, involved in the signal transduction pathway, showed immunoreactivity in the sensory cell layer. Our results demonstrate that the canine vomeronasal organ contains a population of cells that expresses several neuronal markers. Furthermore, GAP43 immunoreactivity suggests that the sensory epithelium is neurogenic in adult dogs.     

Usefulness of quantitative buffy coat blood parasite detection system in diagnosis of malaria

A rapid test for diagnosis of malaria based on acridine orange staining of centrifuged blood samples in a microhematocrit tube (QBC) was compared with thick and thin peripheral blood smears in 2274 samples. Malaria was diagnosed in 239 (10.5%) patients by Leishman's staining technique and QBC method. The QBC method allowed detection of an additional 89 (3.9%) cases. Thus the prevalence rate of malaria during the study was 14.4%. In 1946 patients who were negative by the QBC technique, the Leishman's stained smears did not provide any help in malaria diagnosis. Analysis of the relative quantity of parasites in the specimens, in the QBC method, revealed that 80 out of 89 QBC positive but smear negative cases, had a very low parasite number (less than 10 parasites per QBC field). Although QBC method was superior to the smear for malarial parasite detection, species identification was not possible in 26 (7.9%) cases by this technique. In 95.7% (n = 314) QBC positive cases, the buffy coat in the QBC tube appeared pigmented (gray to black). The colour of the buffy coat was therefore considered by us as a predictor of positivity and could be taken as an indicator for a careful and more prolonged search for the parasites. Thus, the QBC technique has its advantages in terms of speed, sensitivity and ease, especially in an endemic area as ours, where the level of parasitaemia is low and more than 70 to 80 smears need to be examined per day. However, the age old Romanowsky stains still appear superior for species identification.     

Drugs affecting homocysteine metabolism: impact on cardiovascular risk

Elevated total plasma homocysteine has been established as an independent risk factor for thrombosis and cardiovascular disease. A strong relationship between plasma homocysteine levels and mortality has been reported in patients with angiographically confirmed coronary artery disease. Homocysteine is a thiol containing amino acid. It can be metabolised by different pathways, requiring various enzymes such as cystathionine beta-synthase and methylenetetrahydrofolate reductase. These reactions also require several co-factors such as vitamin B6 and folate. Medications may interfere with these pathways leading to an alteration of plasma homocysteine levels. Several drugs have been shown to effect homocysteine levels. Some drugs frequently used in patients at risk of cardiovascular disease, such as the fibric acid derivatives used in certain dyslipidaemias and metformin in type 2 (non-insulin-dependent) diabetes mellitus, also raise plasma homocysteine levels. This elevation poses a theoretical risk of negating some of the benefits of these drugs. The mechanisms by which drugs alter plasma homocysteine levels vary. Drugs such as cholestyramine and metformin interfere with vitamin absorption from the gut. Interference with folate and homocysteine metabolism by methotrexate, nicotinic acid (niacin) and fibric acid derivatives, may lead to increased plasma homocysteine levels. Treatment with folate or vitamins B6 and B12 lowers plasma homocysteine levels effectively and is relatively inexpensive. Although it still remains to be demonstrated that lowering plasma homocysteine levels reduces cardiovascular morbidity, surrogate markers for cardiovascular disease have been shown to improve with treatment of hyperhomocystenaemia. Would drugs like metformin, fibric acid derivatives and nicotinic acid be more effective in lowering cardiovascular morbidity and mortality, if the accompanying hyperhomocysteinaemia is treated? The purpose of this review is to highlight the importance of homocysteine as a risk factor, and examine the role and implications of drug induced modulation of homocysteine metabolism.     

Oedematogenic activity induced by Kunitz-type inhibitors from Dimorphandra mollis seeds.

Proteinase inhibitors from plants represent a form of storage protein or may be involved in plant defense mechanisms against pests and diseases. In this study, we have investigated the oedematogenic activity of DMTI (20 kDa) and DMTI-II (23 kDa), two serine proteinases inhibitors isolated from Dimorphandra mollis (Leguminosae-Mimosoideae) seeds, belonging to the Kunitz family. Paw oedema was induced in male Wistar rats, and measured before and selected times after injection of the proteinase inhibitors. Injection of DMTI-II (3-100 microg/paw) induced a dose-dependent rat paw oedema of rapid onset and short duration, whereas DMTI (3-100 microg/paw) caused a discrete response. The histamine/5-HT receptor antagonist cyproheptadine (2 mg/kg) markedly reduced the DMTI-II-induced oedema. The bradykinin B2 receptor antagonist JE 049 (0.6 mg/kg), the tachykinin NK1 receptor antagonist SR140333 (100 microg/kg) or the NK2 receptor antagonist SR48968 (1 mg/kg) all significantly reduced the DMTI-II-induced oedema. Depletion of sensory neuropeptides by capsaicin also resulted in a significant reduction of oedema formation. In rat isolated peritoneal mast cells, DMTI-II failed to directly release histamine. In conclusion, the proteinase inhibitor DMTI-II induces rat paw oedema by triggering the formation of different inflammatory mediators and pathways, where mast cells and sensory fibers seem to play a pivotal role.     

Reoperative pancreaticoduodenectomy for periampullary carcinoma

BACKGROUND: Potentially resectable periampullary tumours may not be treated appropriately due to lack of local expertise in both assessment of resectability and resection in referring centres. Tata Memorial Hospital is a major referral centre for oncology and these patients are finally referred to this institution. In carefully selected patients, resection can be accomplished. The purpose of the present paper was to determine the perioperative morbidity and mortality for patients undergoing reoperative pancreaticoduodenectomy at a major comprehensive cancer centre. METHODS: Between January 1991 and December 2001 15 patients, who had undergone previous non-resectional surgery for operable periampullary carcinoma, underwent re-exploration. The perioperative morbidity and mortality were analysed and compared with that of the group of patients undergoing primary pancreaticoduodenectomy (143 patients) in the same period. RESULTS: All the 15 patients undergoing re-exploration had a successful resection by pancreaticoduodenectomy. In the reoperative group eight patients (53%) underwent classic pancreaticoduodenectomy and seven patients (46%) had a pylorus-preserving pancreaticoduodenectomy, as compared to 102 (71%) and 41 (29%) patients in the primary surgery group, respectively. Although the mean operative time and the estimated blood loss were higher in the reoperative group, the morbidity and mortality rates were similar in the two groups. The overall 30-day mortality rate was 6.6% and 6.9% in the reoperative and the primary surgery group, respectively. Major morbidity occurred in two of the 15 patients (13.3%), and one patient (6.6%) died following surgery in the reoperative group. CONCLUSION: Reoperative pancreaticoduodenectomy can be performed safely in carefully selected patients with resectable, localized periampullary tumours with similar morbidity and mortality to patients undergoing primary surgery.     

The effect of oestrogen and testosterone on the urethral seam of the developing male mouse genital tubercle

OBJECTIVES: To describe the effects of exogenous oestrogens and androgens on urethral formation in the mouse, as the development of the mouse and human urethra have significant similarities, and understanding normal male urethral development may help to identify the causes of abnormal development, e.g. hypospadias. MATERIALS AND METHODS: Timed-pregnant C57/6 mice were exposed to synthetic oestrogens and androgens. The morphology of the genital tubercles was examined histologically and with three-dimensional computer reconstruction. Specific attention was focused on the developing urethral seam. RESULTS: Microscopic serial analysis confirmed the presence of an arrest in seam formation in about half of oestrogen-treated male fetuses. In contrast, there was acceleration of urethral fold fusion and a longer urethral tube in those treated with androgens. Oestrogen-treated fetuses had a thin periurethral spongiosa, in contrast to androgen-treated fetuses which developed a thicker periurethral spongiosa. The effect of oestrogens on seam area formation did not depend on the dose, but in contrast, in the androgen-treated fetuses it was. CONCLUSION: Oestrogens and androgens have a direct effect on the fusion of the urethral fold that leads to seam formation. Normal urethral development depends on the delicate balance of these complementary hormones.     

Prostaglandins E and F in the uterine tissue of cyclic rats.

Prostaglandins E and F (PGE and PGF) levels and the biosynthetic ability of rat uterine tissue have been estimated in the various phases of oestrous cycle by radioimmunoassay technique. Significantly high PGF concentration was found during metaoestrous phase. In comparison, PGE levels did not show as high elevation. The metaoestrous phase also showed significantly higher biosynthesis of prostaglandins E and F. Our experimental findings support the role of prstaglandins in ovulation and luteolysis of the corpus luteum.