Search PubMed⌕ Search

Biomedical subjects

J Smith

Publications and source records attributed to J Smith.

At least 1,063 records · Page 59Linked to original sources
PubMed1987

Effects of beta-aminopropionitrile after glaucoma filtration surgery: pilot human trial.

Beta-aminopropionitrile fumarate, an inhibitor of collagen cross-linking, was used topically in patients after filtration surgery for difficult cases of glaucoma (aphakic, repeat surgery, neovascular). Twenty-three patients received the drug for a total treatment period of three months following surgery. The mean preoperative intraocular pressure was 40.0 +/- 14.1 mm Hg (mean +/- standard deviation). The mean postoperative pressure was 19.0 +/- 8.9 mm Hg, with the mean follow-up at 26.4 +/- 11 weeks. The overall success rate was 74%, with success being defined as an intraocular pressure of 22 mm Hg or less at the last visit. Side effects consisted primarily of stinging immediately after the medication was applied. Inhibition of collagen cross-linking may represent an alternative method to the use of injectable 5-fluorouracil to maintain patency of filtration blebs.

Administration, Topical↗
PubMed1986

Synthesis of catalytically active choline acetyltransferase in Xenopus oocytes injected with messenger RNA from rat central nervous system.

Choline acetyltransferase (ChAT) mRNA and ChAT enzymatic activity have been compared in different regions of the rat central nervous system. mRNA was assayed by exploiting the Xenopus oocyte system which was first tested by measuring the electrophysiological response to glycine after injection of mRNA derived from the ventral part of the spinal cord (VSC). This tissue was found to contain the highest ChAT mRNA level. The striatum, which yielded the maximal enzymatic activity, contained 10 times less ChAT mRNA than the VSC. These results are discussed in terms of the neuroanatomical differences between the two structures.

Animals↗
PubMed1986

Production of BSF-1 during an in vivo, T-dependent immune response.

BSF-1, a cytokine produced by some T lymphocyte tumors, has been shown to act with anti-Ig antibodies to stimulate B lymphocyte proliferation, to independently induce resting B lymphocytes to increase their expression of surface Ia antigen, and to induce some activated B lymphocytes to differentiate into IgG1- or IgE-secreting cells. To determine whether BSF-1 might be secreted by normal lymphoid cells in the course of a physiologic immune response, BALB/c mice were injected with an affinity-purified goat antibody to mouse IgD (GaM delta), which induces the generation of a large, polyclonal T-dependent IgG1 response; 4-hr culture supernatants of spleen cells from these mice were prepared, and these supernatants were assayed for BSF-1 activity by analyzing their ability to induce BALB/c nu/nu spleen cells to increase their expression of cell surface Ia in vitro. Culture supernatants of unfractionated spleen cells removed from mice 4 to 8 days after GaM delta antibody injection induced substantial increases in B lymphocyte surface Ia expression; these increases were blocked by a monoclonal anti-BSF-1 antibody. Culture supernatants of spleen cells from untreated BALB/c mice or from untreated or GaM delta antibody-treated BALB/c nu/nu mice induced small to moderate increases in B cell surface Ia expression, and GaM delta antibody itself induced large increases in B cell surface Ia expression; however, these increases were not significantly blocked by a monoclonal anti-BSF-1 antibody. A culture supernatant of T cell-enriched spleen cells from untreated mice induced small increases in B cell surface Ia expression that were inhibited by anti-BSF-1 antibody, as was the larger increase in B cell Ia expression induced by a culture supernatant of T cell-enriched spleen cells from mice sacrificed 3 days after GaM delta injection. On the other hand, T cell-depleted spleen cells from BALB/c mice injected with GaM delta antibody 7 days before sacrifice failed to generate culture supernatants with BSF-1 activity. Supernatants prepared from spleen cells taken from untreated mice or mice treated with GaM delta antibody 1 to 3 days before sacrifice did not block the ability of purified BSF-1 to induce an increase in B cell surface Ia expression, and thus did not contain inhibitors of BSF-1 activity.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1986

Osteonecrosis in patients with malignant lymphoma. A review of 31 cases.

Osteonecrosis of the femoral and humeral heads is a serious complication of therapy for Hodgkin's disease and non-Hodgkin's lymphoma. Twenty-five patients were reassessed 5 years after being initially reported, in order to study the further progress and natural history of this complication. In addition, six recent patients who have also developed this condition are presented. With 5-year additional follow-up, no patient had developed symptoms of osteonecrosis in any bone other than those initially involved. Five patients developed severe complications thought to arise from their therapy suggesting that this group of patients were more sensitive to radiation injury than other patients treated with this modality. During the relatively short follow-up 5-year period, a surprising finding was the fact that 31% of the patients with Hodgkin's disease and 50% with non-Hodgkin's lymphoma had died. It is recommended that patients treated for lymphoma with steroid containing chemotherapy and radiotherapy be observed carefully for the occurrence of joint pain. Early diagnosis should lead to attempts to prevent total joint destruction.

Adult↗
PubMed1986

Glaucoma treatment with once-daily levobunolol.

Although twice-daily instillation of topical beta-blockers is the standard regimen for treatment of increased intraocular pressure, once-daily therapy might improve patient compliance and provide greater safety. In a three-month, double-masked clinical trial, 92 patients with open-angle glaucoma or ocular hypertension received levobunolol 0.5% or 1% or timolol 0.5% once daily, in both eyes. Overall mean decreases in intraocular pressure were significantly greater in the groups treated with levobunolol than in the group treated with timolol. Intraocular pressure decreases averaged 7.0 mm Hg with levobunolol 0.5%, 6.5 mm Hg with levobunolol 1%, and 4.5 mm Hg with timolol. The intraocular pressures of 72% (18 of 25 patients) of those treated with levobunolol 0.5%, 79% (22 of 28 patients) of those treated with levobunolol 1%, and 64% (16 of 25 patients) of those treated with timolol were successfully controlled during the study. Heart rate and blood pressure decreases were minimal with both levobunolol and timolol. Study results indicated that once-daily treatment with levobunolol and, to a lesser extent, timolol is sufficient to control intraocular pressure successfully and safely.

Actuarial Analysis↗
PubMed1986

Tinted contact lenses for treatment of retinal degeneration in a Greyhound.

The owner of a Greyhound reported photophobia and disturbance of vision in the dog's left eye. Racing performance, previously excellent, had become erratic under bright lighting. An irregular area of retinal degeneration was observed in the left eye. We used a flush-fitting scleral (haptic) lens made of tinted lucite with visible transmission of 9% to enhance rod function. Behavioral indications and racing performance improved after the fitting of this lens. The report describes a method of contact lens manufacturing, which will help veterinarians solve vision-related problems in domestic animals.

Animals↗
PubMed1986

Coexpression of somatostatin-like immunoreactivity and catecholaminergic properties in neural crest derivatives: comodulation of peptidergic and adrenergic differentiation in cultured neural crest.

In the avian embryo, somatostatin-like immunoreactivity (SLI) and adrenergic characteristics appear virtually simultaneously in the developing sympathetic nervous system and adrenal medulla. We have used double-labeling techniques to show that both properties coexist in the same cells. In the quail, not only do all somatostatin-containing cells in the adrenosympathetic system exhibit tyrosine hydroxylase immunoreactivity and possess catecholamines (CA), but this coexistence of the peptidergic and adrenergic phenotypes is already present very early in ontogeny. However, not all adrenergic cells express SLI. The development of sympathoadrenal precursors can be followed in vitro. Adrenergic precursor cells, obtained from the migrating neural crest, differentiate in culture into neuron-like cells that contain SLI and CA. This coexpression can be regulated by the same factors. For instance, corticosterone and progesterone increase SLI content and CA production in the neural crest cell cultures. The ontogeny of the autonomic lineage is discussed in the light of these results.

Adrenal Medulla↗
PubMed1986

Trichomonas vaginalis: electrophoretic analysis and heterogeneity among isolates due to high-molecular-weight trichomonad proteins.

The protein composition of Trichomonas vaginalis isolates was evaluated using one-dimensional and two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography. At least two hundred intrinsically labeled and about 30 major extrinsically labeled proteins of molecular weights less than 120,000 were resolved by isoelectric focusing and electrophoresis. In general, long-term grown and fresh isolates of T. vaginalis gave similar fluorograms of the readily detectable proteins. Only a minor variance in a distinct protein was noted among three of the four fresh isolated tested. Labeling with [35S]methionine or 3H-amino acids gave almost identical profiles, ensuring the efficient radiolabeling of trichomonad proteins that dominate quantitatively. Comparative analysis of radioactivity profiles of one-dimensional gels emphasizing the region of high-molecular-weight proteins known to reside in low copy number revealed the presence or absence of the internally synthesized proteins from surfaces of T. vaginalis isolates. Finally, immunoblotting of two-dimensional gels demonstrated the highly immunogenic nature of proteins corresponding to quantitatively dominant molecular weight regions of intrinsically labeled proteins.

Animals↗
PubMed1986

Data quality in a distributed data processing system: the SHEP Pilot Study.

The Systolic Hypertension in the Elderly Program (SHEP) Pilot was a collaborative clinical trial that distributed to the clinics all data processing tasks except for randomization assignment codes and morbidity and mortality data. The clinics used customized programs to enter and verify data interactively, to maintain their own local master files, and to transmit the data electronically to the Coordinating Center. We measured quality control based on criteria from centralized as well as distributed models: the error rate for baseline forms was 0.5 per 1000 items. Ninety-eight percent of the forms were query-free, and a central reentry of the data in a 5% sample yielded a miskey rate of 2 per 1000 items. The potential problems of distributed data processing are vulnerability of the local master files and the time demands on Coordinating Center programmers for maintaining clinic computer systems. The advantages are the active involvement of clinic staff in their own quality control, the functional accessibility of the clinics to the Coordinating Center in controlling protocol decisions and data monitoring, and the level of accuracy, completeness, and timeliness of the data that can be achieved.

Aged↗
PubMed1986

A nonpuerperal traumatic vulvar hematoma.

A case is presented where a nonpuerperal traumatic vulvar hematoma was initially mistaken for a Bartholin's gland duct abscess. Since the treatment may be different, the importance of clinical differentiation between these two entities is stressed. Proper management of the vulvar hematomas involves bed rest, close observation, and early surgical intervention only when absolutely necessary. Patients with significant vulvar hematomas should be hospitalized and closely followed.

Abscess↗
PubMed1986

Biological studies of the fusion function of California serogroup Bunyaviruses.

Like other enveloped viruses, La Crosse virus is capable of inducing membrane fusion after exposure to mild acid. This function is known to have biological significance at the level of the whole organism, since it has been related to infection in a mouse model. In this report the process of fusion-from-within (FFWI) for LAC and other members of the California serogroup of Bunyaviruses is characterized. Like fusion-from-without, FFWI is dependent on pH, temperature, and number of virus particles present in the supernatant of fusing cells. Electron micrographs demonstrate that LAC mediated cell membrane fusion is a rapid, multi-point event, and that other than fusion of their plasma membranes, the cells do not show any morphological change. In agreement with theory, lysosomotropic agents were capable of inhibiting La Crosse virus infection. This inhibition was not due to non-specific toxic effects on infected cells. Finally, fusion studies of other California serogroup members revealed minor differences in the pH of fusion induction in some strains. These differences were consistent with the known subtyping within the serogroup.

Animals↗
PubMed1986

Immunoturbidimetric assay of transferrin: effect of iron and need for serum blanks.

The introduction of specific antisera has led to the replacement of total iron binding capacity assays with direct immunochemical measures of transferrin. However, some controversy exists over the effect of the degree of iron saturation on antigen-antibody interactions in these immunochemical assays. This study describes a simple automated immunoturbidimetric assay of transferrin, and includes a reference range and an evaluation of the effects of common potential interferents, including iron, bilirubin, lipemia, and hemoglobin. The measured and the calculated TIBC are also compared for 78 healthy individuals and 51 patients with anemia.

Antigen-Antibody Complex↗