vinay kumar - Academia.edu (original) (raw)

Papers by vinay kumar

International Journal of Cardiology, 1989

A 30-year-old man was admitted with severe chest pain and electrocardiographic evidence of myocar... more A 30-year-old man was admitted with severe chest pain and electrocardiographic evidence of myocardial infarction. Subsequent angiography revealed myocardial bridging of the middle third of the left anterior descending coronary artery and no evidence of coronary atherosclerosis. In the absence of other risk factors, circumstantial evidence points to a possible etiological role of myocardial bridging in the ischemic event in our patient.

Vaccine, 2000

Aldehyde-containing triterpene saponins have adjuvant properties, but only those from Quillaja sa... more Aldehyde-containing triterpene saponins have adjuvant properties, but only those from Quillaja saponaria Molina stimulate the production of cytotoxic T lymphocytes (CTL) against exogenous antigens. Quillaja saponins have two normonoterpene ester moieties, linked linearly to their fucosyl residue, that play a critical role in the stimulation of CTL. These ester moieties are also responsible for these saponins' instability and toxicity. Based on the structure±activity relationships for the dierent groups of Q. saponaria saponins, new semi-synthetic analogs were developed that have the adjuvanticity of quillaja saponins, yet with less toxicity and greater stability in aqueous solutions. The quillaja saponin analogs were prepared by replacing their hydrolytically unstable ester groups with another lipophilic chain linked by a stable amide bond on these saponins' glucuronic acid residue. One of these analogs, GPI-0100, is a dodecylamide saponin derivative that stimulates an antibody isotype pro®le that corresponds to a Th1 type immune response, as well as CTL production against exogenous antigens. 7

Proceedings of The National Academy of Sciences, 2004

HIV-1 and other retroviruses occasionally undergo hypermutation, characterized by a high rate of ... more HIV-1 and other retroviruses occasionally undergo hypermutation, characterized by a high rate of G-to-A substitution. Recently, the human apolipoprotein B mRNA-editing, enzyme-catalytic, polypeptide-like 3G (APOBEC3G), first identified as CEM15, was shown to be packaged into retroviral virions and to deaminate deoxycytidine to deoxyuridine in newly synthesized viral minusstrand DNA, thereby inducing G-to-A hypermutation.

This paper describes a trainable system capable of tracking faces and facial features like eyes a... more This paper describes a trainable system capable of tracking faces and facial features like eyes and nostrils and estimating basic mouth features such as degrees of openness and smile in real time. In developing this system, we have addressed the twin issues of image representation and algorithms for learning. We have used the invariance properties of image representations based on Haar wavelets to robustly capture various facial features. Similarly, unlike previous approaches this system is entirely trained using examples and does not rely on a priori (hand-crafted) models of facial features based on optical flow or facial musculature. The system works in several stages that begin with face detection, followed by localization of facial features and estimation of mouth parameters. Each of these stages is formulated as a problem in supervised learning from examples. We apply the new and robust technique of support vector machines (SVM) for classification in the stage of skin segmentation, face detection and eye detection. Estimation of mouth parameters is modeled as a regression from a sparse subset of coefficients (basis functions) of an overcomplete dictionary of Haar wavelets.

Molecular and Cellular Endocrinology, 2000

Ovarian tissue storage at low temperatures is a promising new method for protecting young cancer ... more Ovarian tissue storage at low temperatures is a promising new method for protecting young cancer patients from the sterilizing effects of chemotherapy and/or radiotherapy. Tissue can be stored and returned to the body in due course as a thin cortical graft since the primordial follicles are distributed peripherally and are relatively resistant to ischaemia. Slices of tissue donated by healthy patients were trimmed to a uniform size and preserved by slow freezing to liquid nitrogen temperatures for up to 2 months hi one of the following cryoprotectants: dimethylsulphoxide, ethylene glycol, glycerol, propylene glycol. Their viability was assessed by counting follicles in histological sections 18 days after grafting under the kidney capsules of severe combined immunodeficiency (SCED) mice, and the results were expressed as percentages of the numbers in comparable pieces of ungrafted tissue. While only 10% of the total number of follicles was found in the glycerol group compared to controls, significantly higher percentages (44-84%) survived cryopreservation hi the other media. The tissues were sterile when frozen and thawed without a cryoprotectant These results suggest that if comparable results could be achieved by autografting, a patient's fertility should be safeguarded from cytotoxic treatment

Lancet, 2001

Interpretation The measurement of these adhesion molecules is unlikely to add much predictive inf... more Interpretation The measurement of these adhesion molecules is unlikely to add much predictive information to that provided by more established risk factors. 2001; 358: 971-75

Kidney International, 1991

Autonomic functions were evaluated in 25 nondialyzed patients with chronic renal failure and eigh... more Autonomic functions were evaluated in 25 nondialyzed patients with chronic renal failure and eight controls. Eight patients were reassessed after 6.6 +/- 1.0 weeks of hemodialysis and 12 patients were restudied 24 +/- 4.0 weeks after renal transplantation. In addition, six patients who had been on maintenance hemodialysis for a duration of 21.5 +/- 3.0 weeks were also studied. Autonomic function tests, including blood pressure and heart rate response to sudden loud noise, mental arithmetic, hand immersion in cold water, Valsalva maneuver, change in posture and respiration, were performed using brachial artery cannulation and continuous monitoring by electrocardiogram. Baroreceptor sensitivity slope was determined using bolus injections of phenylephrine. Supine and standing plasma norepinephrine levels were measured. The cold pressor test, response to sudden loud noise and mental arithmetic were normal in nondialyzed patients with chronic renal failure, suggesting an intact efferent sympathetic pathway. The plasma norepinephrine concentration varied widely but the mean value was similar to the control group (P greater than 0.05). Expiration/inspiration ratio, lying/standing ratio, Valsalva ratio and the baroreceptor sensitivity slope were significantly abnormal (P less than 0.001) in nondialyzed patients. This indicates a defective efferent parasympathetic pathway and depressed baroreceptor sensitivity. The blood pressure response to phenylephrine was lower in the uremics, suggesting a reduced end-organ responsiveness to alpha agonists. The presence of hypertension did not affect autonomic function. The heart rate response to standing and the baroreceptor sensitivity were significantly lower (P less than 0.05) in patients who developed hypotension during hemodialysis. Lower baroreflex sensitivity could contribute to hypotension during dialysis. Autonomic functions remained unaltered after short- and long-term dialysis.(ABSTRACT TRUNCATED AT 250 WORDS)

International Journal of Cardiology, 1989

A 30-year-old man was admitted with severe chest pain and electrocardiographic evidence of myocar... more A 30-year-old man was admitted with severe chest pain and electrocardiographic evidence of myocardial infarction. Subsequent angiography revealed myocardial bridging of the middle third of the left anterior descending coronary artery and no evidence of coronary atherosclerosis. In the absence of other risk factors, circumstantial evidence points to a possible etiological role of myocardial bridging in the ischemic event in our patient.

Vaccine, 2000

Aldehyde-containing triterpene saponins have adjuvant properties, but only those from Quillaja sa... more Aldehyde-containing triterpene saponins have adjuvant properties, but only those from Quillaja saponaria Molina stimulate the production of cytotoxic T lymphocytes (CTL) against exogenous antigens. Quillaja saponins have two normonoterpene ester moieties, linked linearly to their fucosyl residue, that play a critical role in the stimulation of CTL. These ester moieties are also responsible for these saponins' instability and toxicity. Based on the structure±activity relationships for the dierent groups of Q. saponaria saponins, new semi-synthetic analogs were developed that have the adjuvanticity of quillaja saponins, yet with less toxicity and greater stability in aqueous solutions. The quillaja saponin analogs were prepared by replacing their hydrolytically unstable ester groups with another lipophilic chain linked by a stable amide bond on these saponins' glucuronic acid residue. One of these analogs, GPI-0100, is a dodecylamide saponin derivative that stimulates an antibody isotype pro®le that corresponds to a Th1 type immune response, as well as CTL production against exogenous antigens. 7

Proceedings of The National Academy of Sciences, 2004

HIV-1 and other retroviruses occasionally undergo hypermutation, characterized by a high rate of ... more HIV-1 and other retroviruses occasionally undergo hypermutation, characterized by a high rate of G-to-A substitution. Recently, the human apolipoprotein B mRNA-editing, enzyme-catalytic, polypeptide-like 3G (APOBEC3G), first identified as CEM15, was shown to be packaged into retroviral virions and to deaminate deoxycytidine to deoxyuridine in newly synthesized viral minusstrand DNA, thereby inducing G-to-A hypermutation.

This paper describes a trainable system capable of tracking faces and facial features like eyes a... more This paper describes a trainable system capable of tracking faces and facial features like eyes and nostrils and estimating basic mouth features such as degrees of openness and smile in real time. In developing this system, we have addressed the twin issues of image representation and algorithms for learning. We have used the invariance properties of image representations based on Haar wavelets to robustly capture various facial features. Similarly, unlike previous approaches this system is entirely trained using examples and does not rely on a priori (hand-crafted) models of facial features based on optical flow or facial musculature. The system works in several stages that begin with face detection, followed by localization of facial features and estimation of mouth parameters. Each of these stages is formulated as a problem in supervised learning from examples. We apply the new and robust technique of support vector machines (SVM) for classification in the stage of skin segmentation, face detection and eye detection. Estimation of mouth parameters is modeled as a regression from a sparse subset of coefficients (basis functions) of an overcomplete dictionary of Haar wavelets.

Molecular and Cellular Endocrinology, 2000

Ovarian tissue storage at low temperatures is a promising new method for protecting young cancer ... more Ovarian tissue storage at low temperatures is a promising new method for protecting young cancer patients from the sterilizing effects of chemotherapy and/or radiotherapy. Tissue can be stored and returned to the body in due course as a thin cortical graft since the primordial follicles are distributed peripherally and are relatively resistant to ischaemia. Slices of tissue donated by healthy patients were trimmed to a uniform size and preserved by slow freezing to liquid nitrogen temperatures for up to 2 months hi one of the following cryoprotectants: dimethylsulphoxide, ethylene glycol, glycerol, propylene glycol. Their viability was assessed by counting follicles in histological sections 18 days after grafting under the kidney capsules of severe combined immunodeficiency (SCED) mice, and the results were expressed as percentages of the numbers in comparable pieces of ungrafted tissue. While only 10% of the total number of follicles was found in the glycerol group compared to controls, significantly higher percentages (44-84%) survived cryopreservation hi the other media. The tissues were sterile when frozen and thawed without a cryoprotectant These results suggest that if comparable results could be achieved by autografting, a patient's fertility should be safeguarded from cytotoxic treatment

Lancet, 2001

Interpretation The measurement of these adhesion molecules is unlikely to add much predictive inf... more Interpretation The measurement of these adhesion molecules is unlikely to add much predictive information to that provided by more established risk factors. 2001; 358: 971-75

Kidney International, 1991

Autonomic functions were evaluated in 25 nondialyzed patients with chronic renal failure and eigh... more Autonomic functions were evaluated in 25 nondialyzed patients with chronic renal failure and eight controls. Eight patients were reassessed after 6.6 +/- 1.0 weeks of hemodialysis and 12 patients were restudied 24 +/- 4.0 weeks after renal transplantation. In addition, six patients who had been on maintenance hemodialysis for a duration of 21.5 +/- 3.0 weeks were also studied. Autonomic function tests, including blood pressure and heart rate response to sudden loud noise, mental arithmetic, hand immersion in cold water, Valsalva maneuver, change in posture and respiration, were performed using brachial artery cannulation and continuous monitoring by electrocardiogram. Baroreceptor sensitivity slope was determined using bolus injections of phenylephrine. Supine and standing plasma norepinephrine levels were measured. The cold pressor test, response to sudden loud noise and mental arithmetic were normal in nondialyzed patients with chronic renal failure, suggesting an intact efferent sympathetic pathway. The plasma norepinephrine concentration varied widely but the mean value was similar to the control group (P greater than 0.05). Expiration/inspiration ratio, lying/standing ratio, Valsalva ratio and the baroreceptor sensitivity slope were significantly abnormal (P less than 0.001) in nondialyzed patients. This indicates a defective efferent parasympathetic pathway and depressed baroreceptor sensitivity. The blood pressure response to phenylephrine was lower in the uremics, suggesting a reduced end-organ responsiveness to alpha agonists. The presence of hypertension did not affect autonomic function. The heart rate response to standing and the baroreceptor sensitivity were significantly lower (P less than 0.05) in patients who developed hypotension during hemodialysis. Lower baroreflex sensitivity could contribute to hypotension during dialysis. Autonomic functions remained unaltered after short- and long-term dialysis.(ABSTRACT TRUNCATED AT 250 WORDS)