Search PubMed⌕ Search

Biomedical subjects

J G Smith

Publications and source records attributed to J G Smith.

At least 145 records · Page 8Linked to original sources
PubMed1988

The role of natural killer cells in histoplasmosis.

The natural killer (NK) cell has been suggested as an early defense mechanism against Histoplasma capsulatum. Homozygous bg/bg mice, heterozygous bg/+ mice, and bg/+ mice treated with anti-asialo GM1 (ASGM1) were used to assess this postulated role. NK cell assays demonstrated that ASGM1 was effective in reduction of NK cell activity in bg/+ mice to levels comparable to bg/bg mice. To test for possible cross reaction with other immune cells and ASGM1, we evaluated lymphocyte and macrophage function. These studies included lymphocyte transformation, delayed-type hypersensitivity (DTH), and macrophage candidacidal activity. We found no evidence of any effects from ASGM1. Mice were evaluated for survival and colony counts after intravenous (i.v.) H. capsulatum challenge. We again confirmed increased susceptibility of bg/bg mice to H. capsulatum, but found no significant differences between bg/+ mice and bg/+ mice treated with ASGM1. Therefore, we conclude that NK cells play no major role in nonspecific early host defenses against H. capsulatum.

Animals↗
PubMed1988

Paraquat poisoning by skin absorption: a review.

All reported cases of paraquat poisoning by absorption through the skin are briefly reviewed. It is concluded that, while paraquat cannot be absorbed significantly through intact human skin, damage to the skin, either by paraquat itself or by other means, will permit greater systemic absorption and possibly poisoning. The lowest known concentration of paraquat to result in fatal poisoning through the skin is 5 g/l. Animal experiments with paraquat are also reviewed. The fact that the reported lethal dermal dose of paraquat in rats is slightly less than the oral dose is probably due to the lack of head restraint on the rats in the dermal dosing experiments. In vivo and in vitro tests on human skin at concentrations of 9 g/l and 5 g/l did not result in significant absorption of paraquat through the skin but in these experiments the skin was intact.

Animals↗
PubMed1987

Efficacy of topical isotretinoin 0.05% gel in acne vulgaris: results of a multicenter, double-blind investigation.

Two hundred sixty-eight patients with mild to moderate acne vulgaris completed a multicenter, double-blind, controlled study comparing isotretinoin 0.05% gel with its vehicle. Patients were treated twice daily for up to 14 weeks. Efficacy was measured by counting facial inflammatory and noninflammatory lesions and by grading acne severity initially and at 2- to 3-week intervals throughout the study. The isotretinoin 0.05% gel proved to be statistically more effective than vehicle in reducing inflammatory lesions after 5 weeks and in reducing noninflammatory lesions and acne severity grade after 8 weeks. Except for two patients who dropped out because of irritation, isotretinoin 0.05% gel was well tolerated.

Acne Vulgaris↗
PubMed1987

Use of gloves among dermatologists.

Despite evidence that rubber or latex surgeon's gloves appear to prevent or reduce the transmission of hepatitis B virus, physicians continue to perform surgical procedures without wearing gloves. Surveys regarding glove usage among members of the American Academy of Dermatology revealed that a majority of those responding do not regularly wear gloves while performing basic dermatologic procedures, such as shave and punch biopsies and curettage and desiccation. Others are still not wearing gloves regularly while performing excisional surgery, hair transplants, and dermabrasion procedures.

Dermatologic Surgical Procedures↗
PubMed1987

Antifungal agents in dermatology.

Development of new antifungal agents has increased significantly over the past two decades, with recent advances reflecting interest in synthetic agents as opposed to antibiotics. We review the various antifungal medications in use or under development, beginning with a discussion of over-the-counter agents, antibiotics, and older azole compounds and ending with an evaluation of newer azoles and the new class of antifungals, the allylamines.

Antifungal Agents↗
PubMed1987

Hyperkeratosis lenticularis perstans (Flegel's disease). Case report and literature review.

A case of Flegel's disease, or hyperkeratosis lenticularis perstans, is reported. This rare chronic disorder is characterized by asymptomatic hyperkeratotic papules, usually located on the lower extremities. Most reported cases have been from Europe. We report a case of hyperkeratosis lenticularis perstans from our institution that was treated successfully with topical 5-fluorouracil.

Administration, Cutaneous↗
PubMed1987

Responses of peripheral blood cells and lymphocyte subpopulations to insulin-induced hypoglycaemia in human insulin-dependent (Type 1) diabetes.

Changes in counts of peripheral blood cells including lymphocytes and lymphocyte subpopulations were examined in response to acute insulin-induced hypoglycaemia in fourteen insulin-dependent diabetic patients of differing duration, and in eight normal subjects. In patients with a short duration of diabetes (less than 5 years) an initial lymphocytosis preceded a later granulocytosis, similar to changes in the normal group following hypoglycaemia. The lymphocytosis comprised increments in T11 (total), T4 (helper), and T8 (suppressor/cytotoxic) lymphocyte subsets, but B lymphocytes did not rise. In diabetic patients of longer duration (greater than 15 years) the initial lymphocytosis was attenuated, the T4 subset response being absent and the T11 subset response was diminished. The lower lymphocyte responses in the long-term diabetics were unrelated to differences in the hormonal responses to hypoglycaemia or to the rate of blood glucose recovery. Rapid mobilization of specific lymphocyte subpopulations appears to be abnormal in long-term insulin-dependent diabetes, and may indicate underlying immunological dysfunction.

Adolescent↗
PubMed1986

The incidence and possible relevance of Bence-Jones protein in the sera of patients with multiple myeloma.

We present results showing that the detectable incidence of Bence-Jones protein in the sera of patients with multiple myeloma is equivalent to the highest detectable incidence of Bence-Jones protein in highly concentrated urine when tested by immuno-isoelectric focusing. In a series of 25 multiple myeloma patients, immuno-isoelectric focusing showed the incidence of Bence-Jones proteinemia to be 68% compared with a detectable incidence of Bence-Jones proteinuria of 32-64% by immunoelectrophoresis and immuno-isoelectric focusing depending upon the urine concentration factor. In view of the variability of factors governing urinary Bence-Jones protein levels, such as renal catabolism, reabsorption and losses during concentration, we suggest that monitoring of serum Bence-Jones protein by immuno-isoelectric focusing should be carried out in conjunction with measurements of urinary Bence-Jones protein in multiple myeloma.

Adult↗
PubMed1986

Progesterone inhibits proliferation of human marrow colony forming cells (CFU-GM) through increased prostaglandin production by marrow macrophages.

Progesterone inhibited proliferation of granulocyte/macrophage progenitor cells (CFU-GM) in human bone marrow cultured in methylcellulose; the inhibition ranged from 8% at 3 X 10(-9) M, 22% at 3 X 10(-8) M to 38% at 3 X 10(-7) M progesterone in 14 non-malignant marrows. Depletion of marrow monocytes/macrophages with a monoclonal antibody MO2, abolished the inhibitory effect of progesterone. However, production of colony stimulating activity (CSA) did not appear to be affected, either in PHA stimulated peripheral blood or in bone marrow. Indomethacin, a prostaglandin synthetase inhibitor, greatly reduced the degree of inhibition and the addition of prostaglandin E1 (PGE1) to culture in concentrations as low as 10(-12) M completely removed any additional inhibitory effect of progesterone. PGE1 is known to inhibit only those CFU-GM bearing the Ia antigen; we observed that depletion of Ia positive CFU-GM by either 24 h incubation or by monoclonal (I2) treatment, reduced or abolished progesterone mediated inhibition. This confirms that the mechanism of progesterone inhibition of CFU-GM is mediated through increased PGE production by marrow macrophages, and subsequent inhibition by PGE of Ia positive CFU-GM.

Alprostadil↗
PubMed1986

T4: T8-lymphocyte ratios in human bone marrow: the effect of sampling technique.

Marrow aspirate and trephine biopsy T4 : T8-lymphocyte ratios were compared with peripheral blood values. To do this, a new technique for harvesting marrow cells from trephine biopsies is described. Results show that blood and trephine ratios did not overlap. Marrow aspirate ratios were intermediate suggesting that peripheral blood contamination was causing aspirate T4 : T8 ratios to be falsely elevated.

Adolescent↗
PubMed1986

Development and characterization of Histoplasma capsulatum-reactive murine T-cell lines and clones.

Experimental studies have suggested that antigen-specific T lymphocytes are important mediators of resistance to infection with the pathogenic fungus Histoplasma capsulation. To gain a better understanding of the role of T lymphocytes, we developed murine T-cell lines and clones that recognized Histoplasma antigens. These T cells were of the helper/inducer phenotype (Thy-1.2+ Lyt-1+ L3T4+ Lyt-2-) and exerted multiple immunological functions. T-cell lines and 12 clones proliferated vigorously in response to histoplasmin; the T-cell lines and 6 clones also were reactive with heterologous fungal antigens prepared from either Blastomyces dermatitidis or Coccidioides immitis. Recognition of antigen by T cells was H-2 restricted; in the absence of antigen, four clones demonstrated alloreactivity. All T-cell clones conferred local delayed-type hypersensitivity responses when injected with antigen into footpads of mice. Ten of 12 T-cell clones released interleukin-2 after stimulation with antigen, and all clones tested secreted interferon. Moreover, culture supernatants from antigen-stimulated clones armed peritoneal macrophages to inhibit intracellular growth of H. capsulatum yeast cells. All clones assayed exerted nonspecific help. Thus, development of T-cell clones should facilitate analysis of the regulatory properties of Histoplasma-specific T cells.

Animals↗
PubMed1985

An evaluation of a 2% erythromycin ointment in the topical therapy of acne vulgaris.

Two hundred eight patients completed a 12-week, multicenter, double-blind, controlled study comparing a 2% erythromycin ointment to its vehicle. Patients were evaluated by inflammatory lesion counts and Cook acne severity grade at the initial visit and at weeks 2, 4, 8, 10, and 12. The 2% erythromycin ointment proved to be statistically more effective than the vehicle in reducing lesion counts and acne severity grade at weeks 4, 8, 10, and 12. The ointment caused few side effects and was well tolerated by most patients.

Acne Vulgaris↗
PubMed1985

Serologic survey for markers of hepatitis B infection in dermatologists.

A serologic survey for markers of hepatitis B virus (HBV) infection was conducted in 593 dermatologists. Serologic evidence for previous infection was found in 15.4%, indicating that dermatologists are an at-risk population comparable to many other specialties of medicine. Dermatologists with a history of blood transfusion, tattoo, and homosexuality had an increased prevalence of serologic markers for HBV. The type of practice, extent of surgery, and glove-wearing practices did not correlate with HBV serologic markers.

Adult↗