Etiological agents of acute poliomyelitis in South India

This study was done to identify the specific etiological agents that cause acute poliomyelitis (APM). All the children newly diagnosed clinically as APM at the Institute of Child Health, Madras, during the period May 1988 to May 1989 were recruited. Stool specimen collection, transportation and identification of viruses by culture were done by standard procedures. The total number of children recruited was 312. Specimens were contaminated/insufficient in 10. Analysis was done for 302 cases. Polio virus type II was identified in 25.5% children, type I in 18.5%, type III in 15.9%, multiple polioviruses in 6.3% and non-polio enteroviruses (NPEV) in 20.2% cases. No virus was identified in 13.6%. Among the APM cases clinically diagnosed, the proportion of NPEV has increased considerably from 5% in 1984 to 20.2% in 1988–89. The age distribution was not significantly different between polio viruses and NPEV. The distribution of polio viruses and NPEV did not differ significantly in relation to immunization status, source of water supply, method of excreta disposal and the clinical types. For surveillance and control/eradication program of poliomyelitis, laboratory confirmation is essential.     

Development and validation of a cellular transplant model for leukemia in Fischer rats: a short-term assay for potential anti-leukemic chemicals

The efficacy of a leukemia cell transplant model to measure potential chemotherapeutic activity was tested with five different chemicals that had previously been evaluated in 2-year studies. Leukemic spleen cells from Fischer rats were injected subcutaneously into syngeneic recipients and the effects of chemical treatment on tumor progression were evaluated at 70 days post-transplant. The data from the short-term assay were in all cases correlated with the trends reported for mononuclear cell leukemia in 2-year studies, where two chemicals were reported to decrease the incidence and three chemicals were reported to increase the incidence of leukemia. Short-term treatment with the two chemicals which caused negative trends for leukemia (2-ethoxyethanol or ethylene glycol monoethyl ether; 4-hexylresorcinol) delayed and/or reduced tumor growth in the transplant model in a dose-related fashion, as exhibited by reduction or elimination of splenomegaly and leukoblastosis, and a reversal in the depression of red blood cell indices or platelet counts. By contrast, the rate of tumor progression was increased in the short-term assay of the three chemicals which previously caused increased trends for leukemia in 2-year studies (pyridine; 2,4,6-trichlorophenol, dichlorvos). The severity of the mononuclear cell leukemia in the transplant recipients, as measured by histopathological examination of spleen and liver, was correlated with the changes in tumor growth rates. The in vivo leukemia transplant model is a short-term assay that could be used to screen a variety of potential chemotherapeutic agents, or to study structure-activity relationships within one class of chemicals.     

Characterization of specific insulin binding sites in rat testis following induced diabetes and experimental starvation

The presence of insulin-saturable binding sites in the rat testis have been demonstrated. Employing radioreceptor assay (RRA), the characteristics of insulin binding in both liver and testis of the normal (control) rats have been studied. Crude receptor binding at 37 degrees C after 18-20 hrs of incubation in Tris-HCl buffer at pH-7.5. The binding of 125I-insulin to liver and testis of the experimental rats, rendered diabetic for two months with single parenteral streptozotocin (STZ) administration (65 mg/Kg, BW, ip) was also studied. In the diabetic rats, the insulin binding in liver as compared to the control increased by over 92% (P 0.001); the increase in the binding of 125I-insulin to the testis of the diabetic rats however was not statistically significant. Similarly, insulin binding to the testis did not vary much after 3 days of starvation as against 84% (P 0.001) increase in the insulin binding to the liver of the fasted rats. These results suggest that testicular insulin receptors are similar to those of liver but may have a different physiological control.     

A case of bilateral pneumothorax following tracheostomy

Bilateral pneumothorax is a rare but fatal complication after tracheostomy. A 5 year old child, operated for excision of multiple laryngeal papillomata, suffered acute respiratory obstruction under anaesthesia. An emergency tracheostomy was performed. In the immediate postoperative period he developed bilateral pneumothorax and surgical emphysema, which was successfully managed.     

Challenges for the laboratory before and during an influenza pandemic

Laboratory tests that reliably confirm infection with a novel influenza strain are a major component of pandemic planning. Combined nose and throat swabs are the most practical respiratory tract sample to safely obtain from patients. As nucleic acid tests are sensitive, specific and rapid, they will be the diagnostic test of choice during a pandemic. Virus isolation (in laboratories with Physical Containment level 3 facilities) is required for characterisation of the pandemic strain and vaccine development. Antiviral resistance testing may be required if antiviral drugs are used extensively to help control a pandemic. Diagnostic strategies will vary throughout the various pandemic phases.     

The neuro-ophthalmology of pituitary tumors

The management of pituitary tumors requires a multidisciplinary approach involving neurosurgeons, endocrinologists, and ophthalmologists. Patients symptomatic from a pituitary tumor often are first evaluated by an ophthalmologist. This review discusses key issues regarding both the topographic diagnosis as well as the neuro-ophthalmologic manifestations of pituitary disease. Knowledge of the medical, surgical, and radiation treatment options for pituitary tumors is also important in coordinating patient care. The goals of such treatment include the control of tumor growth, normalization of pituitary function, and preservation or restoration of visual function.     

Anesthetic management of a pregnant patient with dengue hemorrhagic fever for emergency cesarean section

Dengue fever is the most common and widespread insect-borne viral infection worldwide. The most critical phase of this viral infection is the defervescent phase when the fever subsides but the patient develops life-threatening thrombocytopenia due to complement activation by viral antigens binding to platelets. We have outlined the anesthetic management of a 25-year-old primigravida with dengue hemorrhagic fever who needed to undergo emergency cesarean section. We also describe this illness in brief and compare the anesthetic management to that of preeclampsia and hemolysis, elevated liver enzymes and low platelet syndrome which this disease mimics.