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Biomedical subjects

A Khan

Publications and source records attributed to A Khan.

At least 649 records · Page 36Linked to original sources
PubMed1969

Respiration-enhancing effect of tuberculin on splenic cells of hypersensitive guinea pigs.

Oxygen utilization in splenic cells of normal and BCG-sensitized guinea pigs was measured in a Warburg respirometer in the absence and in the presence of Old Tuberculin (OT). In the absence of OT, normal and sensitive cells respired at the same rate; in the presence of OT, normal cell respiration remained unchanged, whereas the respiration of sensitive cells increased significantly. This enhancement of oxygen utilization in sensitive cells was induced with OT but not with Purified Protein Derivative and it was most pronounced during the first hour of the interaction between the cells and the antigen. When normal splenic cells were treated with an extract of hypersensitive cells, their respiration was enhanced in the presence of OT. Oxygen utilization in cells of desensitized animals did not differ from that in cells of normal animals. The absence of reactivity to OT in splenic cells and in the skin of desensitized guinea pigs suggested that both phenomena are expressions of antigen-induced biological changes in cells of animals with delayed hypersensitivity.

Animals↗
PubMedDate not supplied

Intraocular lymphoma developing in a patient with Vogt-Koyanagi-Harada syndrome.

A 59-year-old Oriental male with chronic uveitis associated with vitiligo, poliosis, tinnitus and sunset glow fundus was diagnosed as having chronic Vogt-Koyanagi-Harada syndrome. He was treated successfully with steroids (systemic and sub-Tenon's) for two years, but then developed intractable vitritis and visual loss that worsened with the addition of azathioprine. A vitreous biopsy showed large B-cell lymphoma; a mass was also apparent in the subretinal space in the operated eye. Evaluation of the central nervous system was negative for lymphoma. Combined radiation treatment and chemotherapy resulted in dramatic resolution of the intraocular tumor. The possible role of immunosuppression in the development and progression of this tumor is discussed.

Humans↗
PubMedDate not supplied

Significance of mixed features in acute mania.

We studied a group of 23 manic patients to ascertain the prognostic significance of mixed affective features. Eight patients (34.8%) presented with a mixed manic state. This mixed state correlated with a longer hospitalization and significantly worse disposition outcome. In the light of previous conceptual models the authors speculate about the meaning of DSM-III defined mixed bipolar disorder.

Acute Disease↗
PubMedDate not supplied

Onset of response in relation to outcome in depressed outpatients with placebo and imipramine.

We have retrospectively analyzed the results of the pooled data from three 6-week placebo controlled double blind phase III clinical trials, initially designed to assess the efficacy of newer antidepressants, in order to study the relationship of early onset improvement with later outcome in 145 depressed outpatients receiving placebo (n = 98) or imipramine (n = 47). The early onset response was seen in a subgroup of subjects receiving either imipramine or placebo and appeared to be independent of treatment assignment. Furthermore, the early onset response predicted outcome for the duration of the trial and was not selective as defined by specific changes in subscales measuring insomnia, anxiety or endogenous features. Exclusion of early onset responders resulted in the augmentation of the difference in outcome with drug and placebo. We recommend that future placebo controlled trials assessing therapeutic efficacy of active treatments in depressed outpatients take into account the early onset response in the analysis of results.

Adult↗
PubMedDate not supplied

Addison's disease due to metastatic carcinoma: the value of CT scan.

A case of Addison's disease secondary to bilateral adrenal metastasis is reported. The adrenal metastasis were secondary to bronchogenic carcinoma and the diagnosis was made on the basis of the CT scan. The role of CT in the diagnosis of adrenal disease as well as the importance of including the adrenals in the chest CT scan for preoperative staging of bronchogenic carcinoma is discussed.

Addison Disease↗
PubMedDate not supplied

Behavioral teratology investigation of 1-propanol administered by inhalation to rats.

Due to their structural similarity to ethanol, a human teratogen, and their widespread use in industry, a series of industrial alcohols are being investigated for developmental toxicity. This paper presents the results of exposures to 7000 ppm 1-propanol, which is minimally toxic to maternal animals and produces a low incidence of teratogenicity, and to 3500 ppm 1-propanol, which is not toxic to maternal rats and produces no teratogenicity. Propanol vapors or filtered air was administered for 7 hr/day to 15 pregnant Sprague-Dawley rats throughout gestation or to 18 male rats daily for 6 weeks. Tests of offspring were: a) ascent on a wire mesh screen b) rotorod, c) open field and optically monitored activity, d) running wheel, e) avoidance conditioning, and f) progressive fixed ratio schedule of reinforcement. Brains from 10 rats per group were dissected into cerebrum, cerebellum, brainstem, and midbrain, and were assayed for protein, acetylcholine, dopamine, norepinephrine, serotonin, beta-endorphin, Met-enkephalin, and substance P. Overall, the results indicate that exposure to high concentrations of 1-propanol can affect fertility in exposed males (only 2 of 17 produced litters), but there were no consistent effects seen in the behavioral or neurochemical tests measured. This lack of effects is surprising based on predictions from the structural similarity of 1-propanol to ethanol, and on long-standing observations that toxicity (to adult animals) increases with carbon chain length among the aliphatic alcohols.

1-Propanol↗
PubMedDate not supplied

Behavioral teratology investigation of 1-butanol in rats.

Two concentrations of 1-butanol (3000 and 6000 ppm) were administered by inhalation to separate groups of 15 pregnant Sprague-Dawley rats for 7 hr per day throughout gestation; 18 male rats were similarly exposed for 7 hr per day for 6 weeks, and mated to unexposed females. Litters were culled to 4 female and 4 male pups and fostered to untreated controls. From days 10-90, offspring were tested as follows: a) ascent on a wire mesh screen, b) rotorod, c) open field and photoelectrically-monitored activity, d) running wheel, e) avoidance conditioning, and f) operant conditioning. Additionally, brains from 10 offspring at 21 days of age were dissected into cerebrum, cerebellum, brainstem, and midbrain. Each sample was assayed for protein and the neurotransmitters acetylcholine, dopamine, norepinephrine, serotonin, met-enkephalin, beta-endorphin, and substance P. Overall, there were few behavioral or neurochemical alterations detected in the offspring following maternal or paternal exposure to either 3000 or 6000 ppm 1-butanol. This scarcity of effects is important to risk assessment extrapolations drawn from ethanol. Based on the structural similarity of 1-butanol to ethanol and long-standing observations that toxicity to adult animals generally increases with chain length among the alcohols, significant behavioral and neurochemical deviations were predicted. The scarcity of effects from butanol needs to be accounted for in hypotheses relating toxicity to alcohol chain length and in risk assessment extrapolations from findings with ethanol.

Animals↗