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Biomedical subjects

V Gupta

Publications and source records attributed to V Gupta.

At least 55 records · Page 3Linked to original sources

Construction of a HindIII Bacterial Artificial Chromosome library and its use in identification of clones associated with disease resistance in chickpea.

A chickpea ( Cicer arietinum L.) Bacterial Artificial Chromosome (BAC) library from germplasm line, FLIP 84-92C, was constructed to facilitate positional cloning of disease resistance genes and physical mapping of the genome. The BAC library has 23,780 colonies and was calculated to comprise approximately 3.8 haploid-genome equivalents. Studies on 120 randomly chosen clones revealed an average insert size of 100 kb and no empty clones. Colony hybridization using the RUBP carboxylase large subunit as a probe resulted in a very low percentage of chloroplast DNA contamination. Two clones with a combined insert size of 200 kb were isolated after the library was screened with a Sequence Tagged Microsatellite Site (STMS) marker, Ta96, which is tightly linked to a gene ( Foc3) for resistance to fusarium wilt caused by Fusarium oxysporum Schlechtend.: Fr. f. sp. ciceris (Padwick) race 3 at a genetic distance of 1 cM. Also, these two clones were analyzed with several resistance gene analog (RGA) markers. End sequencing of these clones did not identify repetitive sequences. The development of the BAC library will facilitate isolation of Foc3 and allow us to perform physical mapping of this genomic region where additional R genes against other races of the wilt causing pathogen are positioned.

Chromosomes, Artificial, Bacterial↗

Molecular tagging of erucic acid trait in oilseed mustard (Brassica juncea) by QTL mapping and single nucleotide polymorphisms in FAE1 gene.

Molecular mapping and tagging of the erucic acid trait (C22:1) in Brassica juncea was done by a candidate gene approach. Two QTLs underlying the variation of seed erucic acid content were assigned to two linkage groups of a B. juncea map using a doubled haploid (DH) mapping population derived from high x low erucic acid F(1) hybrid. Two consensus primers corresponding to the full-length Fatty Acid Elongase 1 ( FAE1) gene, reported to be involved in the elongation of C18:1 to C22:1, were designed. PCR amplification and subsequent cloning and sequencing identified two FAE1 genes ( FAE1.1 and FAE1.2) in both high and low erucic acid mustard lines. Sequence alignment of corresponding FAE1 genes between high and low erucic acid mustard lines identified four substitution type single nucleotide polymorphisms (SNPs) in FAE1.1 and three in FAE1.2. Using the SNuPE method of SNP genotyping, these two genes were mapped to two independent loci that co-segregated with the two QTLs governing the erucic acid trait. Association of wild ( E1E2) and mutant ( e1e2) haplotypes of two FAE1 genes with erucic acid variation in two segregating populations revealed that the e1e1e2e2 genotype identified low erucic acid individuals (<2%) and E1E1E2E2 identified individuals with highest erucic acid content (>40%). The E1e1E2e2 heterozygote was found to be intermediate in phenotype. The applicability of these SNPs in marker-assisted manipulation of the erucic acid trait was verified by genotyping a set of contrasting germplasm of B. juncea belonging to two distinct gene pools (Indian and east European) and other oil-yielding Brassica species.

Acetyltransferases↗

Optimization of immobilized metal ion affinity chromatography for single-step purification of recombinant ovine growth hormone expressed in Escherichia coli.

In the present investigation, Sepharose 6B gel with 1,4-butanediol diglycidyl ether as spacer arm, iminodiacetic acid as the ligand and Cu2+, Ni2+ as metal ions were used to prepare an immobilized metal ion affinity (IMA) gel. The binding capacities of recombinant ovine growth hormone (roGH) onto IMA gels were maximized in the packed bed column. Parameters influencing the purification efficiencies such as pH, ionic strength and flow-rate were optimized to achieve improved separation. The roGH was purified from inclusion bodies with an overall yield of 73.5% and purity of 94.3% using a Cu(2+)-iminodiacetic acid (IDA) column. However, the Ni(2+)-IDA column was more successful in purifying the roGH from crude cell lysate in a single-step with a yield of 83% and purity of 92.5%.

Animals↗

Association of high-altitude systemic hypertension with the deletion allele-of the angiotensin-converting enzyme (ACE) gene.

People who visit high-altitude areas are exposed to a stressful environment and a good percentage of them suffer from high-altitude-induced diseases, including systemic hypertension. Identification of genetic markers for high-altitude-induced diseases would help to reduce the rate of morbidity/mortality from such diseases. The development of systemic hypertension on exposure to high altitude (3,500 m) for 30 days in otherwise normotensive natives of low-altitudes was investigated. The angiotensin-converting enzyme (ACE) insertion/deletion (I/D) genotypes and renin-angiotensin-aldosterone system were simultaneously studied. In the hypertensives during their stay at high altitude, the ACE D allele frequency was significantly higher than in the normotensives (0.67 versus 0.32 chi(2)(1) = 10.6, P < 0.05). In the normotensives during their stay at high altitude, there was no significant increase in plasma aldosterone levels despite increased plasma renin activity. Results of the present study suggest that environmental changes and pre-existing genetic factors, namely the ACE D allele, might be two of the factors predisposing natives of low altitudes to systemic hypertension, a polygenic disease, at high altitude.

Adaptation, Physiological↗

Facial vein draining into external jugular vein in humans: its variations, phylogenetic retention and clinical relevance.

The superficial veins, especially the external jugular vein (EJV), are increasingly being utilized for cannulation to conduct diagnostic procedures or intravenous therapies. Ultrasound-guided venipuncture is a viable possibility in cases of variations in the patterns of superficial veins, and their knowledge is also important for surgeons doing reconstructive surgery. This study was done on 89 dissected adult cadavers (178 sides) and variations in patterns of termination of the facial vein (FV) into the EJV were studied. The FV in 16 sides (9%) was found to drain into the EJV, in two main patterns: type I and type II. Type I had the FV draining into the EJV with varying degrees of obliquity in a Y-shaped (6 cases, 37.5%), U-shaped (3 cases, 18.7%), tuning-fork-shaped (2 cases, 12.5%) or N-shaped (1 case, 6.2%) pattern. Type II showed an inverted A-shaped pattern (2 cases, 12.5%) or a stepladder-shaped pattern (2 cases, 12.5%) depending on the presence of one or more connecting conduits between the FV and EJV respectively. In Macaca mulatta(rhesus monkey) a pair of vertically disposed, subcutaneous veins placed nearly side by side and of equal caliber were seen on each side of the neck. The lateral vein was the EJV while the medial one took the course of the FV in the upper oblique segment and ran parallel to the EJV in the lower segment over the sternocleidomastoid, with one or two transverse communications. The anomalous patterns found in our study could be explained in terms of the regression and retention of various parts of the veins found in the rhesus monkey, or the drainage pattern found in horse, ox and dog, where the vein from the face drain into the external jugular vein, the internal jugular vein being either absent or a small vessel accompanying the carotid artery.

Adult↗

Myeloablative conditioning regimens for AML allografts: 30 years later.

During the last three decades, several myeloablative conditioning regimens have been used for AML allografts. In this review, we systematically examine the data from studies reporting on myeloablative conditioning regimens for AML allografts. High-dose busulfan combined with cyclophosphamide (BuCy) and cyclophosphamide in combination with total body irradiation (CyTBI) are the two most commonly used conditioning regimens for AML allografts. From the available data, there are no significant differences in survival with these two regimens. A small benefit of decreased relapse rate with CyTBI is counterbalanced by a nonsignificant increase in treatment-related mortality. The incidence of veno-occlusive disease is significantly higher in patients treated with BuCy. Therapeutic monitoring of busulfan was not reported in any of the studies comparing the regimens. Either of the regimens can be used for AML allografts, and the choice may ultimately depend on local availability and expertise. Further improvements may be possible from modifications of the standard regimens. Data from these latter studies seem to be encouraging, but are not based on comparative randomized trials.

Acute Disease↗

Isolated central canal rupture of spinal dermoid: report of two cases.

We report two cases of lumbar spinal dermoid cysts with asymptomatic rupture and migration of free fat droplets into the central canal. No fatty droplets were seen within the lumbar subarachnoid space. The presence of fat droplets within the central canal is unusual because the central canal is rudimentary in adults. We suggest that hydromyelia secondary to tumour and specific tumour morphology might facilitate the selective rupture of dermoids into the central canal. We recommend a follow up of these patients to detect any possible intracranial migration of fat droplets and resultant complications.

Adult↗

Imatinib Mesylate (Gleevec) is a useful agent in the salvage treatment of adults with relapsed/refractory Philadelphia positive acute leukemias.

Philadelphia chromosome-positive (Ph+) acute leukemias have a markedly poor prognosis when treated with conventional chemotherapy alone. Even with intensive treatment such as allogeneic transplant, a large proportion of patients relapse. We describe here four cases of relapsed/refractory Ph+ acute leukemias who were treated with Imatinib Mesylate (Gleevec) as monotherapy. Significant clinical and molecular responses were observed in these patients, which allowed us to deliver highly intensive treatments such as second allogeneic stem cell transplant and matched unrelated transplant in these patients. Gleevec may prove to be a useful agent in the salvage therapy of such patients.

Adult↗

Association of familial leukemia with HLA Cw3: is it real?

A kindred with familial leukemia is described in which three members are affected by leukemia in three consecutive generations. One of these members had Philadelphia positive chronic myeloid leukemia (CML) and other two had precursor B acute lymphoblasticleukemia (ALL)--Philadelphia negative. All three of them shared a common haplotype A2, B55, Cw3. In addition, another member sharing same haplotype developed metastatic breast cancer. Phenomenon of anticipation is demonstrated in the affected family members. Possible causes of genetic susceptibility to leukemia especially the association of Cw3 with familial leukemia are discussed.

Adolescent↗

Vascular events associated with alpha interferon therapy.

Alpha Interferon (IFN) is a biological agent used for the therapy of an increasing number of diseases, either as an established effective therapeutic tool or in the context of clinical trials. The use of IFN may be complicated by serious adverse reactions. We describe here the clinical course of a variety of vasculopathic complications in association with IFN-therapy in 12 patients with the diagnosis of chronic myeloid leukemia and 1 patient with malignant melanoma treated at our institute. Vascular manifestations in these patients include Raynaud's phenomena, digital ulcerations and gangrene, pulmonary vasculitis, pulmonary hypertension and thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS). These reactions occurred after 3 months to 3 years of 3-10 million units (MU) daily IFN therapy. Concomitant administration of hydroxyurea (HU) was noted in 5 patients. Discontinuation of IFN and initiation of immunosuppressive therapy brought about a complete resolution or arrested progression of these reactions. IFN-therapy may be complicated by severe vasculopathic/vasospastic complications that usually improve after its discontinuation. Possible underlying mechanisms for these complications are discussed. The early diagnosis of these complications may be vital and IFN should be immediately discontinued when early signs of these complications become evident.

Adult↗

Two novel somatic mutations in the human interleukin 6 promoter region in a patient with sporadic breast cancer.

Two new single nucleotide mutations were observed within the promoter region of human interleukin-6 gene (IL-6) in the tumour sample of a patient with sporadic breast cancer, which was a somatic change. Both mutations, one at -125 (C > G) and the other at position -173 (G > T) from the translation start site, were transversions observed at new positions, not reported earlier. In addition to these two novel mutations in this patient, a known somatic polymorphism was also observed at position -174 (G > C) (from the transcription initiation site, redesignated as -236 from the translational initiation site as per the HUGO nomenclature). Further, a preliminary comparative analysis of the studied promoter region by the 'ConsInspector 3.0' program, where the mutated sequence (AF362378) was compared with the sequence existing in the database (Y00081), depicted the presence of the variations in putative binding sites for transcription factors such as glucocorticoid response element (GRE) and nuclear factor kappa-B (NFkappa-B), which could lead to differential expression of this gene.

Base Sequence↗

Endoscopic third ventriculostomy in obstructed hydrocephalus.

Forty-three ETV were performed in 46 patients of obstructive hydrocephalus. Study was divided into two groups. Group 1 was with 29 children of less than two years age. Group 2 had seventeen patients of more than 2 years, adolescent and adults. Group 1 had 70% clinical and 63% radiological improvement whereas Group 2 showed 100% clinical and 73% radiological improvement. ETV failed in relieving the symptoms of hydrocephalus in eight patients. They were eventually benefited with VP Shunt. There was one postoperative death, which was not related to the procedure. ETV is an important alternative to VP Shunt in relieving hydrocephalus due to obstruction in CSF pathway.

Adolescent↗

Fenestration of the posterior communicating artery.

A 21-year-old male presented with sudden onset of right-sided third nerve paresis. Angiogram showed a fenestrated posterior communication artery on the right side and no other vascular anomalies. There was no other lesion that could suggest a cause for the third nerve weakness. Fenestration of the posterior communicating artery has not been reported till date. The case is discussed and the literature on the subject is reviewed.

Adult↗

Glioblastoma of the cerebellum. A report of 3 cases.

Glioblastoma (GBM) is one of the commonest intra cranial tumors. Infratentorial GBM is, however, a rare entity. We report 3 cases of histologically proven posterior fossa GBM. The clinical presentation was of a rapidly growing posterior fossa mass. The diagnosis was made only on histological examination. The radiological features are non-specific and the clinical course same as GBM elsewhere. We describe their clinical presentation, radiological and pathological features and a review of describe the literature.

Adolescent↗

Clinicopathological study of spinal teratomas. A series of 10 case.

AIM: Sacrococcygeal teratomas are common in children, but intramedullary spinal teratomas are rare. We report a series of 10 cases of spinal teratomas, which, to the best of our knowledge, is the largest series of intramedullary teratomas. METHODS: During a period of 15 years (1987-2001) 10 cases of spinal teratomas were diagnosed in our department. The clinical profile, radiological data and histopathological slides were reviewed. RESULTS: Age ranged from 10 months to 51 years (mean 23.5 years) with male predominence. Duration of symptoms varied from 5 months to 20 years (mean 4.1 years). The most common symptoms were weakness of lower limbs, backache and urinary bladder involvement. Radiologically, these were heterogenous lesions with fat signal and areas of calcification. Surgery is the treatment of choice. Only 1 case recurred after 9 years of operation. CONCLUSION: Although there are no specific features on imaging of intramedullary teratomas, solid and cystic morphology, fat signal and areas of calcification are some of the helpful features. Most of these lesions are diagnosed on histopathological examination after surgery. Surgery is the treatment of the choice.

Adult↗

Cerebrotendinous xanthomatosis: neuroimaging findings in two siblings from an Indian family.

Cerebrotendinous xanthomatosis (CTX) is exceptionally rare in the Indian population. We present and discuss the clinical, radiological and histopathologic findings in 2 siblings with CTX. Both the patients had juvenile cataract, mental retardation and marked cerebellar ataxia. The Achilles tendon swelling was present in only 1 patient (Case 2). MR imaging showed typical bilateral and symmetrical involvement of the dentate nuclei, inferior olives, brainstem and cerebellar hemispheric white matter. Although the diagnosis of CTX was made in the 3rd decade in both our cases, early diagnosis is possible if neuroimaging is done in the early course of the disease.

Adult↗

Subdural hemorrhage associated with falcine meningioma.

A case of falcine meningioma associated with acute subdural hemorrhage is reported. The possible mechanisms of hemorrhage in the case are discussed. We believe that an early recognition and surgery can prevent neurological deterioration.

Aged↗

A high-density linkage map in Brassica juncea (Indian mustard) using AFLP and RFLP markers.

A high-density genetic linkage map of Brassica juncea (2n = 36) was constructed with 996 AFLP (amplified fragment length polymorphism) and 33 RFLP (restriction fragment length polymorphism) markers using a F1-derived doubled-haploid (DH) population of 123 individuals. This mapping population was developed by crossing a well-adapted, extensively grown Indian variety Varuna and a canola quality line Heera. The two lines are highly divergent and contain a number of contrasting qualitative and quantitative traits of high agronomic value. AFLPs were generated by the use of restriction enzymes EcoRI or PstI in combination with either MseI or TaqI. Using 91 primer pairs, a total of 1,576 parental polymorphic bands were detected of which 996 were used for mapping. In addition, 33 RFLP markers, developed from genomic clones of B. napus, were added to the map. The segregation of each marker and linkage analysis was performed using the program JoinMap version 2.0. The 1,029 mapped-markers were aligned in 18 linkage groups, which is the haploid chromosome number of the species, at LOD values ranging from 5 to 8. The total map length was 1,629 cM with an average marker interval of 3.5 cM. AFLP markers generated by EcoRI were more clustered, whereas PstI markers showed more extensive distribution. A set of 26 primer pairs (9 EcoRI/ MseI, 6 EcoRI/ TaqI, 6 PstI/ MseI and 5 PstI/ TaqI) generating 385 markers were identified for AFLP-based whole-genome selection as these markers covered 96% of the genome mapped with the 91 primer pairs. The map developed in the present study could be used for dissection and the transfer of agronomically important traits and favourable QTLs from ill-adapted exotic germplasm to cultivated Indian varieties.

Crosses, Genetic↗