Pathogenetic factors underlying juvenile deep vein thrombosis (DVT) in Indians

The role of hereditary antithrombotic protein defects in juvenile deep vein thrombosis (DVT) was evaluated. Fifty six young patients (age <45 yr) with doppler-proven DVT were investigated for the presence of resistance to activated protein C (APC-R), lupus anticoagulant (LA), anticardiolipin antibodies and deficiencies of protein C, protein S, ATIII activities. Fifty nine normal healthy individuals served as controls. APC-R was observed to be the commonest defect underlying the Indian DVT as seen in 39.2% of patients followed by elevated ACA (5.3%), PAI (2.8%), presence of LA (2.8%) and reduced ATIII levels (2.8%). None of the subjects had protein C or S deficiency. APC-R was associated with ATIII deficiency in one case, and elevated ACA in two cases. In two subjects, APC-R was associated with elevated PAI levels. Patients with more than one prothrombotic factor had a higher prevalence of pulmonary thromboembolism, suggesting that the thrombogenic potential of APC-R is enhanced by the presence of coexisting hereditary or acquired prothrombotic defect.

Familial gliomas : a case report

Two non-twin brothers were found to have intracranial malignant neoplasms. The age of presentation was third and fourth decade but the onset was simultaneous, at the same time. Diagnosis in each of them was made by computed tomography and confirmed by histopathology. Elder among them had cellular ependymoma and the younger had oligodendroglioma. Both the brothers received radiotherapy post operatively and were surviving asymptomatically without any neurological deficit, leading active life as police constable, 12 months after surgical treatment.

Clinico-haematological profile of isolated PF3 availability defect: therapeutic potential of soya bean--a pilot study

Isolated platelet factor 3 (PF3) availability defect has been observed to be a common platelet functional disorder (PFD) in the Department of Haematology, All India Institute of Medical Sciences, New Delhi, India. One hundred and thirty-two patients were diagnosed to have this defect based on the presence of reduced PF3 availability, normal platelet aggregation with ADP, collagen, adrenaline, ristocetin, and arachidonic acid and normal PF3 content. PF3 availability was evaluated by measurement of Russel viper venom time (RVVT) on the patient's platelet-rich plasma (PRP) after incubation with ADP for 20 min. An RVVT value >19.0 s was considered diagnostic of reduced PF3 availability in patients with normal prothrombin and activated partial thromboplastin times. Isolated PF3 availability defect occurred in patients with ages between 2 and 65 yr and had a female preponderance (M:F=1:2). One fifth of the patients had a positive family history of similar mild bleeding diathesis, indicating an autosomal dominant pattern of inheritance. All patients presented with mild bleeding manifestations, the commonest symptom being appearance of recurrent ecchymotic spots. In females, menorrhagia was the commonest symptom. A pilot study was conducted on 45 patients to evaluate the therapeutic role of oral soya bean (50 g/d). The clinical response was evaluated after 3 months. Soya therapy resulted in disappearance of bleeding problems in 5 patients and reduction in frequency and severity of bleeding in 26 patients. A repeat PF3 availability test after 3 months of therapy showed complete correction in 4 and partial correction in 12 patients. It is evident from McNemer's test that both the clinical and the laboratory parameters (PF3 availability) showed a similar response to soya therapy (p>0.05). Pre-soya therapy mean PF3 availability values differ significantly from those after soya therapy (p<0.01). Thus, soya bean appears to have a therapeutic potential in isolated PF3 availability defect.

Tumour thickness and relationship to locoregional failure in cancer of the buccal mucosa

AIMS

The TNM system is the main parameter in treatment planning and the prediction of survival in oral cancer. Here, we investigate the role of tumour thickness as a predictor of locoregional failure and survival in node-negative patients.

METHODS

We studied 176 node-negative and early stage gingivo-buccal squamous cell carcinoma patients retrospectively. Clinico-pathological factors investigated for tumour failure prediction were: T stage; tumour differentiation; tumour thickness; and treatment. Tumour thickness was measured using an ocular micrometer.

RESULTS

Locoregional tumour failure was found in 34% of cases (60 of 176). Tumour differentiation was found not to be statistically significant in predicting tumour failure. The covariates predicting tumour failure were T stage (P<0.05); type of surgical treatment (P<0.05); and tumour thickness (P<0.001). The mean tumour thickness found was 4 mm. Tumours 4 mm in thickness behaved similarly in all three stages and those >4 mm had a higher rate of lymph-node metastasis. No distant metastasis was found in this series.

CONCLUSION

Tumour thickness was found to be an accurate predictor of locoregional failure in early stage cancer of the buccal mucosa.

Risk factors for thrombosis in nonembolic cerebrovascular disease

Thirty-seven young patients (less than 42 years of age) presenting with sudden onset of idiopathic nonembolic cerebrovascular disease were evaluated for underlying prothrombotic factors. Activated protein C resistance (APC-R) was measured by Dahlback's method and the modified method using factor V-deficient plasma. Activities of antithrombin (AT) III, protein C and S were measured. Anticardiolipin antibody was estimated by ELISA and lupus anticoagulant by kaolin clotting tests. APC-R was the most common defect (21.62%) followed by AT III deficiency and presence of anticardiolipin antibodies (5.6% each). The latter two were present together in one case. It is thus concluded that APC-R is the most common defect underlying idiopathic nonembolic cerebrovascular infarction in young individuals.

Keratosis punctata palmaris et plantaris

A 30-year-old man presented with multiple keratotic papules on palms and soles. The lesions started at the age of 15 from soles. Family history was positive with members in preceding two generations being affected. Cutaneous examination revealed multiple discrete hyperkeratotic papules of variable size on palms and soles. Parakeratosis was absent in histopathology and this ruled out the diagnosis of porokeratosis punctata palmaris et plantaris.

Immunochromatographic test for the diagnosis of Falciparum malaria

The diagnosis of malaria poses great difficulty at times due to non-availability of microscope, trained personnel or laboratory set up. We undertook the immunochromatographic test in 98 suspected cases of malaria for the detection of antigen of P. falciparum in the blood and to assess its sensitivity and positive predictive value. The sensitivity was 87.06% (confidence interval 77.57 to 92.55%) and the positive predictive value was 93.67%. This is a simple, sensitive and convenient test which can be performed in remote areas.

Lymphangioma circumscriptum of scrotum of late onset

Lymphangioma circumscriptum is the commonest type of lymphangioma which is characterised by small, grouped vesicles resembling frog spawn. An interesting case of thin walled lymphangioma circumscriptum is reported which started at a late age of 45 years and limited to scrotum in a 70-year old man.

Papillon - lefevre syndrome with mental retardation

A 9-year old boy, born of consanguineous parents, presented with keratoderma of palms and soles associated with severe enamel hypoplasia and mental retardation. A clinical diagnosis of Papillon - Lefevre was supported by histopathology.

Halo characteristics and their influence on companion searches at the starfire optical range

To image extrasolar planets at their large contrast, high-resolution adaptive optics (AO) is needed to correct atmospheric seeing. The 1.5-m AO system at the Starfire Optical Range was used to confirm theoretical models. Halo levels were reduced by a factor of 4, on average, from 0.5 to 3.0 arc sec radius, which when combined with the increased Strehl ratio improved the gain by a factor of 80. Speckle lifetimes ranged from 5 to 30 ms at 0.3 arc sec, which is much longer than the 0.6-ms AO update time. These results show good agreement with predictions for current technology and reveal no limitations, in principle, to the detection of planets by use of AO systems with higher speeds and resolutions.

Prenatal diagnosis of haemophilia

Haemophilia A is a severe bleeding disorder caused by a deficiency in clotting factor VIII (FVIII). It is an X-linked recessive bleeding disorder affecting one in 10,000 males. Prevalence of the haemophilia gene in the general population has increased recently due to advances in treatment, which has resulted in reproductive fitness among heamophiliacs. Patients suffering from this disease and their families are faced with problems relating to morbidity and mortality from the disease. These include a continual risk of uncontrolled bleeding, haemarthroses and subsequent arthropathy and above all, the genetic risk to progeny. Factor VIII gene is very large with 26 exons. Defects in this gene result in the deficiency of FVIII molecule. With the advent of recent advances in the molecular biology, it is possible to identify the multiple molecular defects such as point mutations, premature stop codons, deletions, and inversions etc in the FVIII gene in patients with haemophilia. Nowadays the use of polymerase chain reaction (PCR)-based linkage analysis and direct mutation detection in the chorionic villus sample obtained at 10-12 weeks of gestation has significantly improved the prenatal diagnosis of haemophilia.

Identification and analysis of a gene that is essential for morphogenesis and prespore cell differentiation in Dictyostelium

We have identified a gene (PslA) that is expressed throughout Dictyostelium development and encodes a novel protein that is required for proper aggregation and subsequent cell-type differentiation and morphogenesis. pslA null (pslA-) cells produce large aggregation streams under conditions in which wild-type cells form discrete aggregates. Tips form along the stream, elongate to produce a finger, and eventually form a terminal structure that lacks a true sorus (spore head). More than half of the cells remain as a mass at the base of the developing fingers. The primary defect in the pslA- strain is the inability to induce prespore cell differentiation. Analyses of gene expression show a complete lack of prespore-specific gene expression and no mature spores are produced. In chimeras with wild-type cells, pslA- cells form the prestalk domain and normal, properly proportioned fruiting bodies can be produced. This indicates that pslA- cells are able to interact with wild-type cells and regulate patterning, even though pslA- cells are unable to express prespore cell-type-specific genes, do not participate in prespore cell differentiation and do not produce pslA- spores in the chimeras. While pslA- cells produce mature, vacuolated stalk cells during multicellular development, pslA- cells are unable to do so in vitro in response to exogenous DIF (a morphogen required for prestalk and stalk cell differentiation). These results indicate that pslA- cells exhibit a defect in the prestalk/stalk cell pathways under these experimental conditions. Our results suggest that PslA's primary function is to regulate prespore cell determination very early in the prespore pathway via a cell-autonomous mechanism, possibly at the time of the initial prestalk/prespore cell-fate decision. Indirect immunofluorescence of myc-tagged PslA localizes the protein to the nucleus, suggesting that PslA may function to control the prespore pathway at the level of transcription.

Behavioral and neurochemical alterations following intracerebroventricular administration of anti-serotonin antibodies in adult Balb/c mice

The effects of intracerebroventricular injections of serotonin (5-HT) antibodies were studied for changes in 5-HT, dopamine (DA), their metabolites and norepinephrine (NE) as well as 5-HT mediated behavior in adult mice. While nociceptive thresholds (tail-flick latency) were inhibited in antibody treated animals, tremor response to 5-methoxy-N,N-dimethyl tryptamine administration was increased. 5-HT and DA in the nucleus raphe dorsalis (NRD), substantia nigra (SN), nucleus caudatus putamen (NCP) and in the substantia grisea centralis, and NE in the former two nuclei were significantly decreased in these animals. 5-Hydroxyindoleacetic acid was unaffected in all nuclei except NRD, where it was inhibited. Homovanillic acid and 3,4-dihydroxyphenylacetic acid were inhibited in all nuclei except in NCP. The brunt of insult was more evident in NRD and SN where all neurotransmitters were inhibited for a longer period. 5-HT turnover was increased in all the nuclei, however only SN showed increased DA turnover. It may be assumed that the observed neurochemical and behavioral changes were the consequence of the antibodies binding to 5-HT, which in turn influenced the anatomically and functionally connected neurotransmitters. While the study contributes to the existing understanding of central neurotransmitter control on behavior, it fails to delineate the underlying mechanism. The possibility of developing a useful, drug-free 5-HT deficient animal model for studying clinical disorders, as well as for solving some of the basic questions related to the physiological functions of 5-HT in adult animals are envisaged from the study.

Flow Behaviour of Blends of Poly(ethylene-Co-Acrylic Acid) and Epoxidised Natural Rubber

Processability and rheological properties of the blends of poly(ethylene-Co-acrylic acid) (PEA) and epoxidised natural rubber (ENR) have been studied by a Monsanto Processibility Tester (MPT). The blends were found to be miscible during reactive processing due to chemical interaction via esterification reaction at higher proportion of PEA. The rheological properties were studied at three different temperatures (120°C, 130°C and 150°C), five different shear rates in the range from 122s−1 to 2452s−1 and at three different shear stresses (i.e., 400, 500 and 600 kPa). The melt viscosities of the blends at 120°C and 130°C show a positive deviation at lower shear rates and shear stress and at higher proportions of PEA and a negative deviation at higher shear rates and shear stress and lower proportion of PEA, where as at higher temperature (i.e. at 150°C) of melt processing the viscosities show positive deviation (at all shear rates for all the blends) with respect to that calculated by additivity rule. This variation in melt viscosities has been explained on the basis of chemical reaction via esterification leading to grafted structure i.e., PEA-g-ENR.