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T Klein

Publications and source records attributed to T Klein.

At least 181 records · Page 10Linked to original sources
PubMed1991

Close association of HLA-B51 and B52 in Israeli patients with Behçet's syndrome.

Epidemiological data, family history, clinical data, and HLA typing were studied in three groups of patients with Behçet's syndrome: six Israeli Ashkenazi Jews, 29 non-Ashkenazi Jews, and three Israeli Arabs. HLA-B51 and B52 were present in 24/38 (63%) and 8/38 (21%), respectively, of the patients compared with 13/151 (9%) of the control group for both cases, a relative risk of 18.2 and 2.8 respectively. The syndrome was found in six of the 34 families. Ninety five per cent of the affected family members were either B51 or B52 positive. Eleven of the 14 families (79%) chosen for study contained a close relative of the proband who had recurrent oral ulcers. All the relatives with ulcers, except for one, were B51 or B52 carriers. Recurrent oral ulcers in the patients with Behçet's syndrome began a few years before other manifestations of the syndrome occurred. Our findings suggest that (a) HLA-B51 and HLA-B52 are primarily associated with Behçet's disease of Israeli patients; (b) the familial occurrence of this syndrome is high and occurs predominantly in the B5 positive group; (c) recurrent oral ulcers may be the first symptom of Behçet's syndrome, appearing early in life; HLA analysis can provide the clue for a correct diagnosis; (d) ulcer recurrence is common among members of a family containing a patient with Behçet's syndrome.

Behcet Syndrome↗
PubMed1991

Expression of HLA class I and class II in gastric carcinoma in relation to pathologic stage.

The expression of HLA class I and II antigens was studied in 41 patients with gastric cancer and in 2 normal stomachs. The normal gastric epithelia were diffusely stained for class I antigens. No staining was observed for class II. In gastric cancer an overall reduction in staining was observed, which was related to the degree of tumor penetration through the gastric wall. In tumors which penetrated the mucosa and submucosa only, 80-90% of tumor cells were stained for class I, as well as the normal areas surrounding the tumor. On the other hand, in tumors which penetrated through the organ to the fat, only 10-20% of cells were stained. Staining for class II was observed in only 12 cases, all of them advanced, with penetration to muscle or fat. No staining was observed in the normal areas surrounding the tumor. The importance of HLA antigens in immune surveillance is discussed.

Gastric Mucosa↗
PubMed1991

Functional antagonism between hormone receptor systems: modulation of glycoprotein secretion in secretory epithelial cells.

A physiologic response such as mucin secretion from epithelial cells in vivo may be under the control of several endogenous substances such as acetylcholine, norepinephrine, and vasoactive intestinal peptide (VIP). These substances may simultaneously activate distinct membrane receptors that exist on the same epithelial cells, and this activation may result in reciprocal physiologic responses or functional antagonism. To test whether simultaneous activation of the VIP and muscarinic receptors or of beta-adrenoreceptors and muscarinic receptors affect mucin secretion in a reciprocal manner, we studied some characteristics of the resultant physiologic response in human epithelial cells secreting radiolabeled mucin-like glycoprotein (MLGP). Both basal and methacholine (M.chol)-induced MLGP secretion could be blocked by VIP (1 pM to 1 microM) and by isoproterenol (ISO) (0.1 nM to 10 nM) in a concentration-dependent and reversible manner. In a membrane preparation from the same cells, VIP (1 to 1,000 nM) and ISO (0.1 to 10 microM) stimulated adenylyl cyclase activity in a concentration-dependent and nonadditive manner. In the same membrane preparation, no effect of M.chol was observed on this response to VIP or to ISO. It is proposed that functional antagonism at the cellular level between basal or cholinergic-stimulated mucin secretion and either activated beta-adrenergic or VIP receptors may play a crucial role in modulation of mucin secretion from epithelial cells.

Adenylyl Cyclases↗
PubMed1990

Production of tumor necrosis factor (TNF-alpha) and lymphotoxin (TNF-beta) by murine pre-B and B cell lymphomas.

Media from murine pre-B and B lymphoma cell cultures, but not from myeloma cell cultures, was cytotoxic to WEHI 164 cells, causing these TNF-sensitive targets to release 51Cr. The cytotoxic activity in the culture medium reached maximum levels approximately 4 days after the cell culture was initiated. The constitutive production of the factors was not influenced by depletion of serum from the medium or by the addition of either phorbol ester or bacterial endotoxin. The factor has a Mr greater than 10 kDa, and its cytotoxicity was abolished by anti-serum against murine TNF. Northern blot analysis with the use of cDNA probes to murine tumor necrosis factor (TNF-alpha) and lymphotoxin (LT, TNF-beta) showed high levels of TNF-mRNA in the pre-B cell lines, lower levels in the mature B cell lines and no TNF-mRNA in the myeloma cell lines. LT mRNA was present in pre-B cell lines, at a much lower concentration in only one of the B cell lines, and was not present in three other B lymphomas or in the myelomas tested. The results show a positive correlation between the presence of TNF and/or LT mRNA and the 51Cr-releasing activity present in the cell culture medium. Our data indicate that TNF and LT can be produced by murine B cells and that the synthesis of these cytokines may be restricted to certain differentiation stages of the B cell lineage.

Animals↗
PubMed1990

Immunoadjuvanticity of endotoxins and nontoxic derivatives for normal and leukemic immunocytes.

Studies with FLV infected mice, a model for retrovirus induced acquired immunodeficiency, showed that intact lipopolysaccharide rich extract from Serratia marcescens as well as the nontoxic polysaccharide derivative free of lipid A were equally adjuvantic in enhancing antibody formation to sheep erythrocytes, both in vivo and in vitro. The PS-rich endotoxin derivative had little or no toxic activity in leukemic animals as occurred with intact endotoxin. The adjuvanticity of both the nontoxic polysaccharide derivative as well as the intact endotoxin in enhancing antibody formation in FLV infected mice was evident also in vitro when spleen cells from infected animals were immunized with sheep erythrocytes simultaneously with the polysaccharide in comparison with the LPS. Supernatants from normal spleen cells treated in vitro either with the polysaccharide or the intact endotoxin showed immunoenhancing helper activity for both normal and FLV infected spleen cells and this enhancing activity was due to IL-1 induced by either bacterial product. Thus the immunoenhancing soluble mediator, i.e., IL-1, is induced equally by PS or LPS and has immunorestorative activity for FLV infected animals. The potential value of the nontoxic PS as an immunoadjuvant in retrovirus immunosuppressed lymphoid cells is evident. The results of these studies suggest that further investigations concerning the nature and mechanism involved in such adjuvancticity is warranted.

Adjuvants, Immunologic↗
PubMed1990

Auranofin-induced suppression of autoimmune antibody production and inflammation in genetically autoimmune-prone mice.

The gold compound auranofin and lobenzarit (CCA) were compared in regard to effects on development of an autoimmune-like disease in MRL/1 mice, which normally develop elevated levels of serum anti-DNA antibodies and rheumatoid factor as well as joint lesions similar to those seen in patients with rheumatoid arthritis. MRL/1 mice, which are genetically prone to development of autoimmune disease, were given auranofin or lobenzarit by gavage for 15 weeks, starting at 6 weeks of age. Mice were examined periodically for immunological abnormalities as well as histologic changes in articular joints. The auranofin-treated mice showed marked diminution in development of anti-DNA antibodies and serum rheumatoid factor as compared to control animals. Although higher than in the auranofin-treated animals, CCA-treated mice also had lower levels of serum autoantibodies than those seen in the control animals. Examination of limb joints for histopathologic changes indicated that the auranofin-treated animals developed only the slightest evidence of lesions as compared to control animals. CCA-treated mice also had a lessening of lesion development compared to control animals, but lesions were more developed than in auranofin-treated mice. This study indicates that auranofin is more effective than CCA in diminishing development of autoimmunity in MRL/1 mice.

Administration, Oral↗
PubMed1990

Endosonography of pararectal lymph nodes. In vitro and in vivo evaluation.

One hundred thirteen patients with carcinoma of the rectum were evaluated for lymph node metastases by endorectal ultrasound. With the use of 7.5 MHz and based on different echo patterns, two main groups of lymph nodes can be differentiated: hypoechoic and hyperechoic lymph nodes. Compared with pathologic findings, hypoechoic lymph nodes represent metastases, whereas hyperechoic lymph nodes are visualized due to unspecific inflammation. Lymph node metastases can be predicted with a sensitivity of 72 percent and inflammatory lymph nodes with a specificity of 83 percent. The physical basis of the differentiation of lymph nodes was assessed in vitro by the determination of ultrasound parameters (speed of sound, acoustic impedance, attenuation, and backscattered amplitude). The attenuation coefficient of benign lymph nodes [2.5 dB/(MHz x cm)] is significantly higher than the mean value of lymph node metastases [1.3 db/(MHz x cm)]. The results demonstrate that involved nodes can principally be differentiated from not involved nodes. Micrometastases, mixed lymph nodes, and changing echo patterns within inflammatory nodes explain the accuracy rate of 78 percent.

Acoustics↗
PubMed1990

The expression of HLA class I antigens in germ cell testicular cancer.

The expression of HLA class I antigens in testicular germ cell tumors (TGCTs) was studied by the immunoperoxidase technique. In the normal testicle, the interstitial cells of Leydig as well as most of the germ cells were significantly stained. In typical seminoma, 75% of the tumor cells in stage I and 30% in stage II were stained. In embryonal cell carcinoma, 25% of the cases in stage I and less than 10% of those in stage II were stained. Mature teratoma was stained in most of the cases, whereas in malignant teratoma only 35% of the cases showed some staining of the tumor cells. In mixed tumors each component displayed its characteristic staining pattern. The expression of class I antigens on tumor cells is required for immune recognition and lysis of the tumor by cytotoxic T-cells. The reduced expression of class I antigens that was related to histologic characteristics and stage suggests that some testicular tumors may escape immune surveillance and become biologically more aggressive.

Dysgerminoma↗
PubMed1990

[Postmaterialism and fertility].

"Though changes in values have been analysed [for] two decades, their impact on actual behaviour has almost been neglected. This especially is the case with values concerning marriage and the family which [have been] responsible for behavioural changes. Here, the impact of emerging postmaterialistic values on fertility are analysed, deriving from the assumption that the effect of children on the general life-style is large enough to let fertility behaviour be influenced by general value orientations. The main result is that the emergence of postmaterialism has led to postponement of parenthood whereas the number of children is left untouched." (SUMMARY IN ENG)

Attitude↗
PubMed1989

Photoregulation of a phytochrome gene promoter from oat transferred into rice by particle bombardment.

The regulatory photoreceptor phytochrome controls the transcription of its own phy genes in a negative feedback fashion. We have exploited microprojectile-mediated gene transfer to develop a rapid transient expression assay system for the study of DNA sequences involved in the phytochrome-regulated expression of these genes. The 5'-flanking sequence and part of the structural region of an oat phy gene have been fused to a reporter coding sequence (chloramphenicol acetyltransferase, CAT) and introduced into intact darkgrown seedlings by using high-velocity microprojectiles. Expression is assayable in less than 24 hr from bombardment. The introduced oat phy-CAT fusion gene is expressed and down-regulated by white light in barley, rice, and oat, whereas no expression is detected in three dicots tested, tobacco, cucumber, and Arabidopsis thaliana. In bombarded rice shoots, red/far-red light-reversible repression of expression of the heterologous oat phy-CAT gene shows that it is regulated by phytochrome in a manner parallel to that of the endogenous rice phy genes. These data indicate that the transduction pathway components and promoter sequences involved in autoregulation of phy expression have been evolutionarily conserved between oat and rice. The experiments show the feasibility of using high-velocity microprojectile-mediated gene transfer for the rapid analysis of light-controlled monocot gene promoters in monocot tissues that until now have been recalcitrant to such studies.

Chloramphenicol O-Acetyltransferase↗
PubMed1989

[The expansion of the educational system and the birth decline in the Federal Republic of Germany: a cohort-based simulation on the impact of the changing educational structure on reproductive behavior].

"Demographic studies on cohort fertility have revealed that the birth decline in the [Federal Republic of Germany] was accompanied or even brought about by a considerable postponement in parenthood. By means of event history analysis and micro-simulation this article shows that the postponement of motherhood can be attributed to the expansion of the educational system that took place in the 60s and early 70s. Furthermore, changes in educational structure have contributed markedly to increased childlessness in the younger generation, whereas there is no relation between the reduction in family size and the structural changes in education. The impact of increased education on the family life-cycle can be explained by labour market theories, whereas traditional theories have neglected biographic aspects of fertility." (SUMMARY IN ENG)

Cohort Studies↗
PubMed1989

[Visualization of imperceptible blood contamination in operative hospital areas with the help of chemoluminescence].

Invisible contamination of the skin and other surfaces in the hospital environment with small quantities of blood must be considered a potential source of infection of parenterally transmitted diseases. In the presence of hematin, luminol oxidizes rapidly, emitting visible light in the process. By means of this chemoluminescence reaction, surface contamination with small amounts of blood can be easily visualized. A survey of the hospital environment with this technique revealed that during surgery the extent of blood contamination was much greater than could be judged by the naked eye. Luminol chemoluminescence can be used to spot potential sources of infection of parenterally transmitted diseases and can thus help to reduce their risk of transmission.

Blood↗
PubMed1989

Recombinant interleukin-2-activated intracavitary lymphocytes: phenotypic characteristics and effector function.

A preclinical study of intracavitary lymphocytes (ICL) from malignant effusions of cancer patients is described. The object of this study was to evaluate the antitumor potential of ICL as a baseline for developing adoptive immunotherapy trial for ovarian carcinoma patients. The main parameters studied were functional cytolytic activity of fresh and recombinant interleukin-2 (rIL-2)-activated ICL and their phenotypic characteristics. Spontaneous cytolytic activity of ICL was detected in all samples tested against natural killer (NK)-sensitive targets (K562), while very low activity was shown against NK-resistant targets (Daudi) and fresh tumor cells. Activation in culture with rIL-2 generated cytolytic activity against NK-resistant targets and significantly augmented NK activity. The pattern of antitumor lytic activity of ICL resembles lymphokine-activated killer cell activity and is non-major histocompatibility complex restricted against a variety of tumor targets. Phenotypic characterization of fresh ICL showed the predominance of CD3+ cells with the CD4/CD8 ratio resembling that of peripheral blood lymphocytes. During culture with rIL-2, changes in phenotypic expression of activated ICL were detected: enrichment in NKH1+ cells (up to 65%), of CD8+ (up to 70%), and very late antigen (VLA)-1+ cells (up to 54%), concomitantly with a decrease in CD4+ population. The NKH1, CD8, and VLA-1 expression peaked at 2 weeks in culture and coincided with peak cytolytic activity of cultured ICL. Depletion of CD8+ cells from activated ICL resulted in a decreased proportion of cells expressing the NKH1 and VLA-1 phenotype, whereas depletion CD4+ cells led to enrichment in CD8, NKH1, and VLA-1 antigens. Cytolytic activity was significantly increased in CD4 depleted population against NK-resistant and NK-sensitive targets. In this study we found that rIL-2 activation and culture of ICL generates killer activity against NK-resistant and fresh tumor targets and that enrichment in expression of NKH1, CD8, and VLA-1 antigens is associated with effector function.

Antigens, Surface↗