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Biomedical subjects

A Shaw

Publications and source records attributed to A Shaw.

At least 163 records · Page 9Linked to original sources
PubMed1989

Modulation of antibody-mediated glomerular injury in vivo by bacterial lipopolysaccharide, tumor necrosis factor, and IL-1.

We have investigated the effects of LPS, human rTNF (hrTNF) and human rIL-1 beta (hrIL-1 beta) pretreatment on the intensity of antibody-mediated injury in vivo by using a passive model of anti-glomerular basement membrane (GBM) antibody-mediated nephritis in rats. The experiments show that all three pretreatments exacerbate injury in this model whether judged by albuminuria or the prevalence of glomerular capillary thrombi. The effect on albuminuria was dose dependent with all three treatments. The lowest effective dose of LPS was 0.025 microgram while those for hrTNF and hrIL-1 beta were 0.4 microgram and 0.5 microgram, respectively. All three pretreatments also increased the prevalence of glomerular capillary thrombi which were rare in rats injected with anti-GBM antibodies without pretreatment. LPS pretreatment appeared to be more effective in causing glomerular capillary thrombi than hrTNF or hrIL-1 beta and this was reflected in the correlations between albuminuria and the proportion of glomeruli with capillary thrombi. This relation was linear for all three pretreatments but the slope was appreciably greater for rats pretreated with LPS (0.37) when compared with results from rats given either hrTNF (0.22) or hrIL-1 beta (0.29). Pretreatment of nephritic rats with both cytokines increased the slope to 0.42 demonstrating a synergistic effect. The synergism of hrTNF with hrIL-1 beta was also demonstrated by the effective doses needed to induce albuminuria which was evident in rats treated with 0.05 microgram of IL-1 beta and 0.4 microgram of TNF. Neither the cytokines nor LPS caused clinical, morphologic, or biochemical evidence of renal toxicity when given alone in the dose used here but they did cause a transient increase in the number of neutrophils marginated in glomerular capillaries. Pretreatment of rats with LPS or cytokines increased the glomerular neutrophil influx after anti-GBM antibodies by roughly sixfold. Our experiments show that TNF and IL-1 can increase the severity of glomerular injury in nephritis; they may be important in modulating glomerular injury clinically.

Albuminuria↗
PubMed1989

Reduction of ocular lens dosage in dacrocystography.

Irradiation of the lens of the eye in dacrocystography is largely avoidable. We have measured the lens dosage in bilateral dacrocystography in vivo and in a phantom. We describe simple protective measures which can reduce the lens dosage by over 95% to less than one mGy.

Humans↗
PubMed1989

Interleukin 1 as an autocrine growth factor for acute myeloid leukemia cells.

Production of interleukin 1 (IL-1) by leukemic cells was studied in 13 cases of acute myeloid leukemia. Intracytoplasmic immunofluorescence studies showed that the cells invariably contained the cytokine. Endogenous labeling studies demonstrated that acute myeloid leukemia cells produced either only the 33-kDa propeptide or both the propeptide and the 17-kDa mature form of IL-1 beta. The 33-kDa propeptide IL-1 alpha was always produced but was less frequently released. Involvement of IL-1 in leukemic cell growth was investigated using two antibodies specific for IL-1 subtypes, which inhibited spontaneous cell proliferation in the six cases studied. After acid treatment of the cells, a surface receptor for IL-1 could be demonstrated, which mediated 125I-labeled IL-1-specific uptake by leukemic cells. Furthermore, recombinant IL-1 alpha or IL-1 beta induced significant cell proliferation in 10 of 12 cases. The above findings were uncorrelated with the cytologic type (French-American-British classification) of leukemia. Our studies suggest that IL-1 may act as an autocrine growth factor in most cases of acute myeloid leukemia.

Cell Division↗
PubMed1989

Localization and characterization of the interleukin 1 immunoreactive pool (IL-1 alpha and beta forms) in normal human epidermis.

A panel of polyclonal antisera and monoclonal antibodies (MoAb) raised against recombinant human interleukin 1 alpha (rh IL-1 alpha) and beta (rh IL-1 beta) was used to localize IL-1 pools within epidermal compartments and to characterize the immunoreactive species. Interleukin 1 alpha and beta immunoreactive species were detected by Western blot analysis only when epidermal extracts were obtained in extraction buffers containing dithiothreitol (DTT), sodium dodecyl sulfate (SDS), or 2 mercaptoethanol. Together with the 31-kD (intracellular precursor molecule) and the 17-kD (mature, secreted form) species, most of the antisera and MoAb reacted with a protein of 52-kD that was not found in several internal organs, and from which a 31-kD form could be released upon reelectrophoresis. Interleukin 1 beta immunoreactivity was consistently found by immunohistology at the level of the stratum granulosum, where IL-1 alpha immunoreactivity, although less consistently, also localized. Several monoclonal antibodies to IL-1 beta reacted intensively and specifically with epidermal basal cells. At the electron microscopical level, IL-1 beta immunoreactivity was detected in the upper layers of the stratum granulosum; it appeared to be membrane associated and suggested an exocytosis process similar to that involving lamellar bodies. These observations 1) confirm the presence of IL-1 species in the normal unstimulated human epidermis, 2) show that both IL-1 alpha and beta are detectable herein, 3) identify 52-kD IL-1 alpha and beta immunoreactive bands that appear special to the epidermis, and 4) suggest a link between epidermal IL-1 and the differentiation process of the keratinocyte.

Antibodies, Monoclonal↗
PubMed1989

Bacteria and gallstone nucleation.

This preliminary study reports for the first time that there might be a possible association between bacteria and the aetiology of some cholesterol calculi. The gall-bladder biles from 225 cholecystectomy patients underwent bacteriological and microscopic study. Cholesterol calculi from 13 patients (10.2%) were observed to be associated with gall-bladder bile profusely infected with at least one bacterial species that was shown to possess beta-glucuronidase activity, an enzyme that is thought to promote calcium bilirubinate precipitation in bile. Concomitantly, the associated gall-bladder bile was 'high' in calcium bilirubinate precipitation and the precipitate was also detected in the centre of the gallstones. Moreover, in approximately half of these patients (six of 13), the cholesterol gallstones' nuclear areas also contained calcium palmitate, which is also thought to be due to bacterial activity. The results also support the hypothesis that bacteria with active beta-glucuronidase (for example, Escherichia coli) can significantly influence the aetiology of brown pigment gallstones. In contrast, bacteria were observed to have no role in black pigment gallstone formation, as their associated gall-bladder biles were always observed to be sterile.

Adult↗
PubMed1989

Oligomerization of glycolipid-anchored and soluble forms of the vesicular stomatitis virus glycoprotein.

The vesicular stomatitis virus glycoprotein forms noncovalently linked trimers in the endoplasmic reticulum before being transported to the Golgi apparatus. The experiments reported here were designed to determine if the extracellular domain of the glycoprotein contains structural information sufficient to direct trimer formation. To accomplish this, we generated a construct encoding G protein with the normal transmembrane and anchor sequences replaced with the sequence encoding 53 C-terminal amino acids from the Thy-1.1 glycoprotein. We show here that these sequences were able to specify glycolipid addition to the truncated G protein, probably after cleavage of 31 amino acids derived from Thy-1.1. The glycolipid-anchored G protein formed trimers and was expressed on the cell surface in a form that could be cleaved by phosphoinositol-specific phospholipase C. However, the rate of transport was reduced, compared with that of wild-type G protein. A second form of the G protein was generated by deletion of only the transmembrane and cytoplasmic domains. This mutant protein also formed trimers with relatively high efficiency and was secreted slowly from cells.

Acetylglucosaminidase↗
PubMed1989

Illness-related worry among cancer patients: prevalence, severity, and content.

The present study assessed the prevalence, severity, and other parameters of illness-related worry among 83 cancer patients receiving active treatment for their illness. Participants completed questionnaires assessing a variety of worry dimensions. In addition, a family member of each patient completed a brief questionnaire regarding their perception of the patient's illness-related worry. Nurse ratings of patients' clinic-related behaviors were obtained. Fifty-one percent (n = 43) of patients reported worry to be at least "somewhat of a problem." Fifteen percent (n = 12) reported it to be a significant to severe problem. Significant correlations included patients self-rating of worry and: nurse rating of clinic behavior, total score on a Worry Content Scale, ability to stop worrying once started, and impact of worry on mood and functioning. Rating by the significant other of how much of a problem worry was for the patient and whether the patient was a worrier preillness was also significantly correlated. There were no significant differences between "worriers" and "nonworriers" on demographic or disease variables. A logistic regression model using the categories of "worries" or "nonworriers" as a dependent variable found that women and patients reporting poor social support were more likely to report a problem with worry. However, a large amount of the variance remained unexplained.

Adult↗
PubMed1989

Identification of interleukin 1 alpha produced by the 3B6 human EBV-B cell line.

We have previously described a novel protein, derived from the 3B6 EBV B-cell line which apparently displayed IL-1 bioactivity. We report here that the protein previously characterized is not a new species of IL-1. Indeed, we have now been able to clone and express a cDNA which identifies this protein as human thioredoxin, an intracellular dithiol oxydo-reductase enzyme. Thioredoxin however, is not a lymphokine and in particular does not possess IL-1 activity. Our earlier data can be explained in the light of recent findings, reported herein, indicating that IL-1 alpha is produced by the 3B6 line as assessed by antibody inhibition studies and IL-1 alpha mRNA expression. Thus our original protein preparation actually contained traces of IL-1 alpha, which was responsible for the biologic activities and thioredoxin.

Amino Acid Sequence↗
PubMed1989

Monoclonal antibodies reactive with hairy cell leukemia.

Monoclonal antibodies reactive with hairy cell leukemia were developed to aid in the diagnosis of this subtype of B cell chronic lymphocytic leukemia and to gain better insight into the origin of hairy cells. Three antibodies were found to be of value in the diagnosis of hairy cell leukemia. Antibody B-ly 2 can be considered a pan-B cell reagent and generally reacts similar to CD22 antibodies. Antibody B-ly 6 is reactive with the same antigen as CD11c (p150/95), an antigen that is present on hairy cell leukemia, macrophages, and a minor subpopulation of lymphocytes. Antibody B-ly 7 is a unique antibody reactive with 144 Kd antigen present only on hairy cell leukemia and a very small population of normal B lymphocytes. This subpopulation may be the counterpart of hairy cells.

Antibodies, Monoclonal↗
PubMed1989

Use of focus groups to explore consumers' preferences for content and graphic design of nutrition publications.

The purpose of this research was to determine consumers' preferences for the content and design of nutrition print materials through the use of focus group interviews. Thirty-seven non-pregnant, non-nursing female consumers 20 to 50 years of age attended one of six focus group interviews. Existing nutrition print materials were used to stimulate discussion on content and graphic design features of the materials. Content features discussed included glossaries, quizzes, diet evaluation checklists, diet monitoring forms, and "factual" vs. "how to " information. Graphic design features discussed included color, format, size, organization, and general appearance. Participants were asked to discuss the personal impressions and practical considerations that formed the basis of their opinions regarding each feature and to elaborate on how the existing materials might be improved to meet their particular needs. Features that drew the most positive reactions were bright food colors, organizational cues, clear information and explanations, features that help personalize the issue being addressed, and "how to" information.

Adult↗
PubMed1988

Detection of human IL-1 alpha and IL-1 beta at the subpicomolar level by colorimetric sandwich enzyme immunoassay.

Two separate convenient sandwich enzyme immunoassay methods were developed for measuring the production of the monokines interleukin-1 alpha (IL-1 alpha) and interleukin-1 beta (IL-1 beta) from peripheral blood mononuclear cells. Polyclonal antisera raised against the recombinant proteins and selected on the basis of their ability to neutralize IL-1-induced IL-2 secretion were used for coating microtiter plates or preparing peroxidase-Fab' conjugates. Both techniques were able to accurately and specifically detect monokines from various sources in the sub-picomolar range and were not influenced by compounds currently used for cell activation. A high molecular weight form of IL-1 beta was demonstrated under certain conditions and the two enzyme immunoassays were successfully applied to the detection of IL-1 alpha and IL-1 beta present in cell supernatants following stimulation with mitogenic or chemical agents.

Animals↗
PubMed1988

Genes for IFN-beta-2 (IL-6), tumor necrosis factor, and IL-1 are expressed at high levels in the organs of normal individuals.

The gene of a cytokine designated IFN-beta-2, or IL-6, and recently identified as identical to the B cell-stimulatory factor 2, is transcribed at high levels in the spleen, liver, kidney, and peripheral blood leukocytes of normal individuals. The number of IFN-beta-2/IL-6 transcripts present endogenously in normal human tissues (0.6 to 16 copies/cell) is comparable to that present in normal cells induced in vitro with human rTNF. This is in marked contrast to the absence of detectable IFN-beta-1 transcripts (less than 0.0003 copy/cell) in the same samples of human tissue. The expression of the IFN-beta-2/IL-6 gene is closely associated with that of two other cytokines TNF, and IL-1. Thus, significant levels of IFN-beta-2/IL-6, TNF, IL-1 alpha, and IL-1 beta, mRNA were detected in all the samples of normal tissue tested and those samples which contained high levels of IFN-beta/IL-6 mRNA also contained high levels of TNF, and IL-1 beta mRNA. These results suggest that these cytokines may function in consort as regulators of cellular growth and function in normal tissues.

Gene Expression Regulation↗
PubMed1988

Cloning and expression of a cDNA for human thioredoxin.

Thioredoxin is the best representative enzyme of a group of proteins, widely distributed and possessing dithiol-disulfide oxidoreductase activity. We have constructed a cDNA library from messenger RNAs isolated from a lymphoblastoid B cell line (Epstein-Barr virus-immortalized normal human lymphocytes). Screening of this library with synthetic oligonucleotide probes, constructed from the NH2-terminal amino acid sequence of a protein produced by this line, allowed us to identify a full-length cDNA clone coding for human thioredoxin. The open reading frame (315 nucleotides long) codes for a protein of 104 amino acids (excluding the initial methionine). This protein possesses the highly conserved enzymatic active site common to plant and bacterial thioredoxins: Trp-Cys-Gly-Pro-Cys (amino acids 30-34). These data provide for the first time the complete primary sequence of a thioredoxin of mammalian origin. Recombinant human thioredoxin, expressed in Escherichia coli, possesses a dithiol-reducing enzymatic activity as assayed on mammalian and plant substrates. It is able to reduce the interchain disulfide bridges of murine pentameric IgM and porcin insulin and also to activate vegetal NADP-malate dehydrogenase. Studies of human thioredoxin mRNA expression and regulation in immunocompetent cells of human origin indicate that the protein is weakly expressed in resting lymphocytes and monocytes, but the level of human thioredoxin mRNA transcription is quite important in activated monocytes and established dividing human cell lines.

Amino Acid Sequence↗
PubMed1988

Activation by PHA of CD8 lymphocytes into clonal colony forming cells. Role of interleukin-1.

Monoclonal T cell colonies can be grown in agar culture from quiescent T lymphocytes under PHA stimulation, provided that (1) a low number of T lymphocytes (less than or equal to 5 X 10(4)/ml) is seeded, (2) IL-2 is added to the culture, and (3) a high number of accessory B cells (greater than or equal to 5 X 10(5)/ml) is present in contact with the T lymphocytes. Under these culture conditions the colony progenitors can be ascribed to the CD4 subset, whereas CD8 lymphocytes do not generate colonies. This finding is surprising since both CD4 and CD8 lymphocytes may be cloned in liquid culture. We now report the appropriate conditions required to grow cytotoxic CD8 lymphocyte colonies in agar. CD8 colony growth is dependent upon IL-2-IL-2 receptor interaction and is inhibited by anti-IL-2 receptor antibodies. In addition to PHA, accessory B cells and IL-2, an additional signal provided by recombinant IL-1 is necessary for CD8 colony formation. Exogenous IL-1 can be replaced by irradiated CD4 lymphocytes which stimulate the expression of membrane IL-1 activity in the accessory B cells. In addition, colony growth from quiescent but not preactivated CD8 lymphocytes is inhibited by anti-IL-1 antibodies. Altogether, the data show that an IL-1 signal is required for the induction of IL-2 responsive IL-2 receptors on quiescent CD8 colony forming cells.

Animals↗
PubMed1988

Interleukin 1 alpha acts as an autocrine growth factor for RPMI 1788, an Epstein-Barr virus-transformed human B cell line.

The Epstein-Barr virus-transformed B cell line RPMI 1788 constitutively produces autocrine growth factors with molecular masses of 17 kDa, 24 kDa and 35 kDa. All three molecular forms were completely neutralized with anti-interleukin (IL) 1 alpha antiserum. Although IL 1 alpha and IL 1 beta mRNA were both equally detectable by Northern blotting, no IL 1 beta activity was found in partially purified RPMI 1788 supernatant. The growth of low density-seeded RPMI 1788 cells is specifically dependent on the presence of either IL 1 alpha or IL 1 beta. Since no other cytokine was found to be capable of sustaining proliferation, this cell line is suitable for the identification and quantification of IL 1, even in the presence of other cytokines.

B-Lymphocytes↗
PubMed1988

Protease inhibitors decrease rabbit cartilage degradation after meniscectomy.

In vitro proteoglycan (PG) synthesis and release were measured on cartilage removed from rabbit knees within 1 week of meniscectomy. Three days following partial lateral meniscectomy, 72% of the femurs and 82% of the tibias had visible ulcers. Cartilage from the weight-bearing areas incorporated 2.0-2.9 times more 35S-sulfate in vitro than cartilage from the opposite, unoperated knees. 3H-thymidine incorporation was 2.5-3.4 times higher for surgical than control groups. 35S-sulfate incorporation by the surgical group was inhibited by 22% in the presence of 10(-4) M U24522, an inhibitor of rabbit chondrocyte metalloprotease (CMP). 3H-thymidine incorporation by the surgical group was inhibited by 28% by 10(-4) M U24522. In vitro PG release from cartilage removed 2 days after surgery was 1.6-3.7 times higher for the surgical than the control group. PG release by the surgical group after 22 h of incubation was reduced to the control level by three CMP inhibitors, U24278, U24279, and U24522. PG release by cartilage from the nonsurgical group was also reduced by these compounds at 22 h. These results suggest that both the anabolic and catabolic processes that are stimulated by surgery can be isolated in vitro and that CMP may be involved in the catabolic process.

Animals↗
PubMed1988

Fertility and child spacing among the urban poor in a third world city: the case of Calcutta, India.

The author examines the fertility behavior of the urban poor in India. "On the basis of data from 180 slum households in Calcutta, India, the paper indicates that in a situation where material and social conditions are comparable, cultural and demographic variables play a major role in influencing reproductive behavior. In this case study, caste and family type are shown to have a significant effect on the numbers of surviving children. As regards child spacing, the woman's age is of paramount importance."

Age Factors↗