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T Singh

Publications and source records attributed to T Singh.

233 records · Page 13Linked to original sources
PubMedDate not supplied

Gastric mucosal fibrosis: a novel explanation for dyspepsia.

The etiology of functional dyspepsia has not been discerned yet which has led to inadequate treatment of this disease. It remains a common disorder with expensive and yet often ineffective therapy. We propose that the pathogenesis of this disease lies in the histological and ultrastructural changes inflicted on the gastric mucosa in chronic gastritis and fibrosis. This hypothesis, if substantiated will provide for therapy which will be based on the pathogenesis of the disease and which will be cheaper and easily available to most. It will also add impetus to the early eradication of Helicobacter pylori, which would prevent chronic gastritis and hence gastric fibrosis.

Dyspepsia↗
PubMedDate not supplied

Ziconotide, a new N-type calcium channel blocker, administered intrathecally for acute postoperative pain.

BACKGROUND AND OBJECTIVES: Voltage-sensitive calcium channel conductance is essential for the nervous system to signal a painful event. However, intrathecal administration of L-type calcium channel blockers does not provide analgesia. The present investigation was designed to assess the safety and analgesic efficacy of ziconotide, a new N-type calcium channel blocker, when administered intrathecally to patients with acute postoperative pain. METHODS: This randomized, double-blind, pilot study included patients undergoing elective total abdominal hysterectomy, radical prostatectomy, or total hip replacement. After intrathecal injection of local anesthetic and before surgical incision, a continuous intrathecal infusion of either placebo or 1 of 2 doses of ziconotide (0.7 microg/h or 7.0 microg/h) was started and continued for 48 to 72 hours postoperatively. Primary and secondary efficacy variables were the mean daily patient controlled analgesia (PCA) morphine equivalent consumption and visual analog pain intensity (VASPI) scores, respectively. RESULTS: Thirty patients received study drug; 26 were evaluable for efficacy. Mean daily PCA morphine equivalent consumption was less in patients receiving ziconotide than in placebo-treated patients, and the difference was statistically significant between 24 and 48 hours (P = .040). VASPI scores during the first 8 hours postoperatively were markedly lower in ziconotide-treated than in placebo-treated patients. In 4 of 6 patients receiving the high-dose of ziconotide (7 microg/h), adverse events, such as dizziness, blurred vision, nystagmus, and sedation contributed to study drug being discontinued after 24 hours. After ziconotide discontinuation, these symptoms resolved. CONCLUSIONS: Ziconotide showed analgesic activity, as shown by decreased PCA morphine equivalent consumption and lower VASPI scores. Because of a favorable trend of decreased morphine consumption with an acceptable side-effect profile in the low-dose ziconotide group, 0.7 microg/h may be closer to the ideal dose than 7 microg/h. Large-scale studies are required to clarify this issue.

Acute Disease↗
PubMedDate not supplied

Hormone profiles at high altitude in man.

Altitude induced alterations in circulatory levels of PRL, LH, FSH and testosterone were studied in seven eugonadal men at sea level (SL), during their stay at high altitude (HA, 3500 m) and a week after return to SL. The mean plasma PRL level at SL was 5.83 +/- 1.7 SE ng/ml. On day one and seven of arrival at HA, the PRL values of 7.81 +/- 1.81 and 9.21 +/- 1.64 ng/ml respectively were not significantly different (p greater than 0.05) than the initial SL values. However, on day 18 of stay at HA, PRL levels were significantly increased (p less than 0.01) to 17.68 +/- 1.82 ng/ml and returned to initial SL values within seven days of return to SL. A significant decrease (p less than 0.01) in LH and testosterone was observed on seventh day of stay at HA and the decreased levels were maintained till day 18 of observations. Plasma testosterone returned to the initial SL values within a week of return to SL, whereas LH levels remained significantly lower (p less than 0.01). The FSH levels did not show any significant change during their stay at HA or after return to SL. These observations suggest that exposure to altitude is associated with hyperprolactenemia and an impaired pituitary gonadal function. The decreased levels of LH and testosterone at HA could either be due to hypoxic stress per se or secondary to altitude induced hyperprolactenemia.

Adult↗
PubMedDate not supplied

Comparison of brush before biopsy, suction cytology, brush after biopsy and endoscopic biopsy in the diagnosis of carcinoma oesophagus.

A study was conducted on 40 patients of carcinoma oesophagus to compare the diagnostic yield of brush biopsy, suction cytology, brush after biopsy and endoscopic biopsy. The positive yield with brush before biopsy was 87.5%, with suction cytology 90%, with brush after biopsy 100% and with endoscopic biopsy 90%. Difference in the yield of brush after biopsy compared to other modalities was statistically insignificant (P > 0.05). However, the quantitative yield of the material was significantly high (P < 0.05) in the brush after biopsy compared to brush before biopsy. Of these three cytological modalities brush after biopsy appears to be the cytological technique of choice to be used as an adjunct to endoscopic biopsy.

Biopsy↗
PubMedDate not supplied

A multistate model for the fluorescence response of R-phycoerythrin.

Although strong fluorescence makes the R-phycoerythrin (R-PE) proteins increasingly useful in biological and clinical assays, they are subject to nonlinear effects including transitions to collective dark states and photodegradation, which complicate quantitative applications. We report measurements of R-PE fluorescence intensity as a function of incident power, duration of illumination and temperature. Emission intensity in the band at 570 nm is proportional to incident power for low power levels. At higher incident power, the emission at 570 nm is smaller than expected from a linear dependence on power. We propose that R-PE undergoes both reversible emission cessation on a millisecond time scale attributed to transitions to a collective dark state, and irreversible photodegradation on a time scale of minutes. Singlet oxygen scavengers such as dithiothreitol and n-propyl gallate have protective effects against the latter effect but not the former. Electrophoretic analysis of irradiated solutions of R-PE indicates that significant noncovalent aggregation is correlated with photodegradation. A multistate model based on fluorescence measurements and geometric analysis is proposed for the fluorophores in R-PE. The phycobilin fluorophores are partitioned into three groups: the phycourobilins (PUB) absorbing at 490 nm, one group of phycoerythobilins (PEB) absorbing at 530 nm (PEB-530) and another group of PEB absorbing at 560 nm (PEB-560). The two processes that result in the loss of fluorescence intensity are most likely associated with the PEB-560 group.

Fluorescence↗
PubMedDate not supplied

Clinico-immunological aspects of vernal catarrh in hilly terrains of Himachal Pradesh.

Very few immunological studies in vernal catarrh have been conducted in India and abroad, but none in Himachal Pradesh in spite of its high incidence in the State. In the present study 25 patients of vernal catarrh residing at a height ranging between 1000 to 2500 meters above mean sea level have been evaluated. Their immunological status of serum and tears after detailed clinical assessment was studied by single radial immunodiffusion technique of Mancini et al. The values of serum IgA and IgM were significantly higher in patients than in controls. The serum IgE level had no significant difference. The IgG was significantly lower in patients with vernal catarrh. The values of tear IgM, IgE and IgA in these patients were significantly higher than in controls. However, in no case or control group C3C and C4 were detected in tears. The limbal type of vernal catarrh was found to be the most common in this part of the country. No mixed case was seen. Derangement of the immune system in the pathogenesis of vernal catarrh is suggested.

Adolescent↗
PubMedDate not supplied

Pulmonary agenesis.

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Adolescent↗
PubMedDate not supplied

Changes over time in survival of children after AIDS diagnosis in New York City.

We determined whether survival of children following AIDS diagnosis is improving over time through 1991. AIDS surveillance data from New York City Department of Health on 914 pediatric AIDS patients, diagnosed between 1979 and 1991 and presumed due to maternal-infant HIV transmission, were analyzed. Survival following AIDS diagnosis, established from hospital records and death certificates, was compared by calendar year of initial diagnosis using Kaplan-Meier lifetable analysis. Cox Proportional Hazards regression models were used to compare survival for patients diagnosed earlier or later in the decade, controlling for age at diagnosis, presenting opportunistic illness, and gender of the child. Patients diagnosed with AIDS from October 1987 to September 1989 survived longer, median survival 17 months after diagnosis, than patients diagnosed before September 1987, median survival 10 months (relative risk [RR] = 0.76; 95% confidence intervals [CI] = 0.62, 0.93). Patients diagnosed from October 1989 to December 1991 also survived a median of 17 months. Secular improvements in survival after AIDS diagnosis remained after controlling for age at diagnosis, presenting diagnosis, and gender, even if deaths within three months of diagnosis were excluded. These data suggest that for recent years, survival following AIDS diagnosis in those contracting the infection through maternal-infant transmission has been prolonged. Possible explanations for these findings include both methodological issues (changes in diagnostic criteria, incomplete ascertainment of deaths) and substantive issues (developments in therapeutic interventions and management of pediatric AIDS).

Acquired Immunodeficiency Syndrome↗