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Meenal Gupta

Publications and source records attributed to Meenal Gupta.

11 recordsLinked to original sources

Topochemical models for the prediction of voltage-gated sodium channel binding activity of hydantoins and related non-hydantoins.

The relationship of Wiener's topochemical index-a distance based topochemical index, molecular connectivity topochemical index-an adjacency based topochemical index and eccentric connectivity topochemical index-an adjacency-cum-distance based topochemical index with sodium channel binding activity has been investigated. A dataset comprising 50 hydantoins and related non-hydantoins was selected. The dataset was divided equally into training and test sets. The values of the three topochemical indices for all the compounds present in both the training and test sets were computed using an in-house computer program. The resulting data was analyzed and suitable models were developed after identification of the active ranges in the training set. Subsequently, a biological activity was assigned to each compound involved in the training set using these models, which was then compared with the reported sodium channel binding activity. An accuracy of prediction of the order of >99% was observed using the proposed models. Cross-validation of these models using the test set revealed an exceptionally high accuracy of approximately 95%.

Chemistry, Pharmaceutical↗

Angiogenesis in myelodysplastic syndromes (MDS) in Indian patients.

Angiogenesis plays an important role in the pathogenesis of haematological neoplasms and may be correlated with the prognosis. We recently evaluated the microvessel densities in trephine biopsy sections of seventeen patients of myelodysplastic syndromes (MDS). Of the 17 cases, 2 were RAEB-t, 3 were RAEB, one was RARS and 11 were of the subtype RA (FAB subtyping). The microvessel counts were measured in the bone marrow biopsy sections by immunohistochemical staining, using CD34 reactive monoclonal antibodies. MVD was significantly higher in the cases of RAEB and RAEB-t as compared to the cases of RA. The average MVD per x400 in the cases of RA was 5.7 +/- 4.7 with a median value of 4.65 (range 19) whereas it was 45.4 +/- 10.0 and 44.0 (range 27.3) respectively in RAEB and RAEB-t (p <.001), the 95% confidence interval being (2.94, 8.5) and (36.6, 54.3), for the two groups respectively. This finding may imply that subtypes of MDS with a higher tendency for converting to acute leukaemia are associated with increased angiogenesis as compared to other subtypes where the risk of progression to acute leukaemia is much lower.

Adolescent↗

Dielectric spectroscopy of a binary mixture of liquid crystals showing wide temperature range twisted grain boundary phase with re-entrant cholesteric phase.

There are only few materials, which have shown long temperature range twisted grain boundary (TGB) phases. One such material is the chiral binary mixture of 7OCB and 5* CBB (mole ratio 0.8 and 0.2) which shows unique phase sequence of cholesteric ( N*) , a wide temperature range TGBA (approximately 31 degrees C) and reentrant cholesteric (N*re) phases. In the present work we are reporting the dielectric spectroscopy of the above mixture with a chiral analog of earlier reported nematic (N) , smectic- A (SmA) , and reentrant nematic (Nre) phase sequences [Phys. Rev. A 46, 7733 (1992)] for different conditions of molecular orientations. Two modes of dielectric relaxations have been detected in a homeotropically aligned sample with unusually low relaxation frequencies for one of them. Planar oriented molecules in the TGBA phase show a soft mode of relaxation and support the recently proposed theory for the soft mode relaxation of the TGBA phase [Phys. Rev. E 65, 11701 (2001)]. By applying the dc electric field on planar oriented molecules in the TGBA phase, it has been possible to obtain a helix free homeotropically aligned TGBA phase.

Journal Article↗

Spectrum of inherited bleeding disorders in Indians.

The incidence of hereditary hemorrhagic disorders may vary according to the country and ethnic origin. Von Willebrand disease has emerged as the most common hereditary hemorrhagic disease in the industrialized world. In this series of 966 patients diagnosed to have inherited bleeding disorders, hemophilia A was the most common and was seen in 410 (42.4%) of the patients followed by platelet function defects seen in 380 (39.4%) of the patients. It is thus concluded that, similar to the white population, hemophilia A remains the most common bleeding disorder in the Indian population, although this is closely followed by platelet function defects in India, which are quite rare in whites. Von Willebrand disease is relatively rare in the Indian population.

Blood Coagulation Disorders↗

Comparative protein profiles of Salmonella and Escherichia coli.

Protein profiles of selected Salmonella serovars were compared with E. coli to identify genus specific protein(s) for Salmonella. The PDP formed of different Salmonella serovars were compared with E. coli O78 when subjected to SDS-PAGE yielded 11, 15, 15, 11 and 14 bands in S. Bareilly, S. Gallinarum, S. Typhimurium and S. Weltevreden and E. coli O78 respectively. The bands produced were compared with each other. It was found that S. Weltevreden shared 7 bands with E. coli O78, A protein of molecular weight 20.89 kDa was found in all Salmonella serovars, but not in E. coli O78 suggesting its genus specific attribute.

Bacterial Proteins↗

Inherited heterogenous defect in platelet aggregation selectively with ADP and epinephrine--a series of 25 cases.

Inherited heterogeneous defects of platelet function caused by impairment of platelet responses to weak agonists as ADP, epinephrine and others as low concentration collagen and platelet activating factor (PAF) have been described, though quite rarely. We describe here 25 cases of this defect with impairment in response to ADP and epinephrine. Subjects with a history of generalized bleeding and a prolonged bleeding time, PF3 availability or prothrombin consumption index and a normal platelet count, prothrombin time, activated partial thromboplastin time and clot solubility were subjected to platelet aggregation. Those of these which showed a normal aggregation with collagen and arachidonic acid and an absent or reduced aggregation with ADP and epinephrine were included in our study group. Subjects with history or findings suggestive of antiplatelet drug intake or any acquired condition affecting platelet functions were excluded from this study. 76% of the patients had onset of recurrent bleeding manifestations since childhood with a mean age at onset of 9.2 years. A positive family history was present in 36% of the patients. Majority of the patients (88%) presented with mild bleeding manifestations, the commonest symptom being appearance of recurrent ecchymotic spots. We present here a series of patients with a hereditary platelet aggregation defect selectively with ADP and epinephrine.

Adenosine Diphosphate↗

Contribution of iron deficiency to anemia in chronic renal failure.

Prevalence of iron deficiency in anemia of chronic renal failure (CRF) has long been the subject of interest, because the patients of CRF with coexistent iron deficiency anemia need to be treated with iron preparations before starting erythropoietin therapy. Prevalence of iron deficiency in CRF is higher in Indian patients as compared to the West. Diagnosis of iron deficiency in patients with CRF is difficult. Bone marrow iron which is considered to be the gold standard is a painful and invasive procedure. In the present study we used serum transferrin receptor and serum ferritin levels, since not much Indian data is available on this.

Adult↗

An unusual platelet function defect: report of 19 cases.

Selective impairment in platelet responsiveness to epinephrine has been seen in certain acquired conditions and very rarely as a hereditary disorder. To the best of our knowledge this hereditary defect has been described in a single family and in two other individuals. We describe here 19 cases of this defect. Subjects with history of generalized bleeding with a prolonged bleeding time, PF3 availability or prothrombin consumption index and a normal platelet count, prothrombin time, activated partial thromboplastin time, clot solubility were subjected to platelet aggregation. Those of these who showed a normal aggregation with ADP, collagen, arachidonic acid and an absent aggregation with epinephrine were included in our study group. Subjects with history or findings suggestive of antiplatelet drug intake or any acquired condition giving rise to this abnormality were excluded from this study. 74% of the patients had onset of bleeding manifestations since childhood (<14 years) with a mean age at onset of 10.4 years. All patients presented with mild bleeding manifestations, the commonest symptom being appearance of recurrent ecchymotic spots. In females, menorrhagia was the commonest symptom. We present here probably the first report of the occurrence of hereditary platelet aggregation defect selectively with epinephrine in Indian patients.

Adolescent↗

Pregnancy associated aplastic anemia--a series of 10 cases with review of literature.

INTRODUCTION: Pregnancy induced aplastic anemia is a rare entity and the association is not well explained. There are approximately 80 cases in the literature and we are presenting the largest series, so far, of 10 cases. RESULTS: Total of 10 cases had 11 pregnancies. Mean age at presentation was 25.45 years and mean gestation when symptoms first developed was 17.09 weeks. Pallor and bleeding manifestations were the most common presenting complaints. Mean Hb, TLC, ANC and platelets were 4.97 g/dl, 2.74 x 10(9)/l, 1.11 x 10(9)/l and 41 x 10(9)/l, respectively. Bone biopsy cellularity ranged from <5 to 25%. Nine out of 11 (81%) pregnancies were successful of which 7 was full term and 2 were premature. Two babies were small for dates. One spontaneous abortion and one intra uterine death (IUD) were observed. Two out of 11 mothers died due to disease after delivery. Two of the 8 surviving mothers, had spontaneous partial response (22%); 4 mothers were asymptomatic after therapy with immunosuppressives given for 6 months and 3 were lost to follow up without response. Specific therapy (cyclosporin) was tried in two mothers antenatally with partial response in one. One child whose mother was given cyclosporin antenatally had jejunal atresia at birth. CONCLUSION: Pregnancy associated aplastic anemia is a rare association. Spontaneous remission can occur in 25-30% of patients. In the first trimester patients, pregnancy can be terminated while in advanced pregnancy patients can be followed up with stringent supportive care. Cyclosporin may be a safe drug antenatally in such patients. Patients with established aplastic anemia should avoid pregnancy.

Abortion, Spontaneous↗