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At least 415 records · Page 23Linked to original sources
PubMed1979

In vitro studies of poison oak immunity. II. Effect of urushiol analogues on the human in vitro response.

Studies were performed to ascertain the effect of urushiol analogues on the in vitro lymphocyte blastogenesis elicited by urushiol in peripheral blood lymphocytes taken from individuals sensitized to poison oak or ivy. Urushiol is a mixture of alkylcatechols composed of a catechol ring coupled to mono-, di-, or tri-unsaturated C-15 or C-17 carbon side chains. Each of these two moieties, catechol ring and side chain, was tested for its role in eliciting reactivity. Analogues tested represented the catechol ring (3-methylcatechol), the mono- or di-unsaturated side chain (oleic or linoleic acid), and the saturated side chain coupled to a catechol ring (pentadecylcatechol), a blocked catechol ring (heptadecylveratrole), or a resorcinol (pentadecylresorcinol). Urushiol with a blocked catechol ring (urushiol dimethyl ether) was also included. Of these, only pentadecylcatechol evoked reactivity in sensitized lymphocytes, and this reactivity was only a fraction of that evoked by urushiol. This suggested that the system has some requirement for the side chain, and that the catechol ring is critical for reactivity. This was further investigated by testing the ability of some of these analogues to inhibit urushiol-specific blastogenesis. No inhibition was noted with compounds bearing the saturated side chain with modified ring structures (pentadecylresorcinol and heptadecylveratrole). However, both 3-methylcatechol and pentadecylcatechol (at equimolar concentrations) blocked reactivity. The results of our experiments suggested that although both the side chain and the catechol ring are required for reactivity, the latter is most critical. Unsaturation in the side chain is important for maximal reactivity because the saturated catechols were only partially as active as the urushiol oil. There may be a greater dose requirement for the catechol ring than for the side chain.

Alkenes↗
PubMed2005

Dynamic in vitro measurement of patellar movement after total knee arthroplasty: an in vitro study.

BACKGROUND: Changing the kinematic behaviour of patellar movement could be one of the reasons for anterior knee pain after implantation of a total knee arthroplasty (TKA). The aim of the current study was to measure the potential influence on patellar kinematics of patellar resurfacing during TKA. METHODS: Patellar movement before and after TKA with and without patellar resurfacing was measured under dynamic conditions in an in vitro cadaver simulation. Physiologic Musculus quadriceps forces were applied to five physiologic human knee specimens undergoing simulated isokinetic extension motions, patellar movement was measured using an ultrasonic measurement system. Thereafter, the Interax I.S.A.-prosthesis system was implanted without and with resurfacing the patella, and patellar movement was again measured. RESULTS: The physiologic patella center moved on a semilunar path up to 6.4 mm (SD 6.4 mm) medially during extension. After TKA, the unresurfaced patella showed significantly less medial translation (p = 0.04) than the resurfaced patella. Subsequent resurfacing of the patella then resulted in a return to mediolateral positioning of the patella similar to the physiological case, whereas the resurfaced patella tilted up to twice as much as physiologic. CONCLUSION: The results of this study suggest that resurfacing of the patella during TKA can result in a restoration of the physiologic mediolateral shift of the patellofemoral joint while angulation of the patella remains unphysiologic.

Aged↗
PubMed1999

[Results of in vitro fertilization therapy methods in Germany in 1996--the German In Vitro Fertilization Registry].

We believe that on the IVF subject, which is nowadays applied exept a standard method in the world. In the next years we could expect further improvement in our success++. It is also to anticipate that next changes in the development of assistance-reproduction will be: 1. Freezing of ovums, 2. To get in vitro-meture of the immature cells, 3. Transplantation of ovarium tissue, 4. Transfer of the blastocyst, 5. Transfer of cytoplasma or the cell nucleus. We recommend that the IVF/ICSI--therapy and birth of children has to be registrated in one central register.

Adult↗
PubMed1975

In vitro studies on target cells of oncogenic adenoviruses in hamster brain. II. In vitro transformation of brain cells of hamsters at various ages by human adenovirus type 12.

In vitro transformations of brain cells of hamsters of various ages were examined after the administration of human adenovirus type 12 (Ad 12) to determine the type and origin of the target cell. Hamster brain cells at all examined ages were transformed by Ad12. Although the virus was not isolated, virus specific tumor antigen was demonstrated in the transformed cells. The histological features of tumors that developed by transplantation of transformed cells closely resembled Ad12-induced brain tumors. The transformed cell focus tended to appear near the embryonic brain cell (EB cell) or glioblastic cell (GB cell). The transformed cells were morphologically similar to the EB or GB cell. Some subcultured transformed cells showed a rosette-like pattern, and the surrounding space arrangement was similar to that of the ventricular wall. The incidence of brain cell transformations decreased with increased hamster age. This decreased incidence with age corresponded to the decreased numbers of EB or GB cells present in progressively older hamsters. From these results, it is concluded that the target cells of AD12 in hamster brain cell cultures are probably the EB or GB cells.

Adenoviridae↗
PubMed1975

In vitro studies on target cells of oncogenic adenoviruses in hamster brain. III. In vitro transformation of brain cells of hamsters at various ages by bovine adenovirus type 3.

In vitro transformation of brain cells of hamsters at various ages was examined after the addition of bovine adenovirus type 3 to determine the type and origin of the target cells. Cellular transformations occurred only in cultures of fetus and newborn animals and at low incidences. Nine cell lines were obtained. Virus specific tumor antigens were demonstrated in the transformed cells. The present investigation suggested that bovine adenovirus type 3 might transform mesenchymal cells (ME cell) and that these cells are probably of meningeal or vascular origin. The histological picture of tumors following transplantation of the transformed cells resembled human primary sarcoma of the meninges and brain.

Adenoviridae↗
PubMed1990

In vitro fertilisation when normal sperm morphology is less than fifteen per cent. Results of in vitro fertilisation and embryo transfer at H.F. Verwoerd Hospital, Pretoria.

The outcome of in vitro fertilisation and embryo transfer in 90 couples where the husband's normal sperm morphology was less than 15% were analysed. Based on the percentage of morphologically normal spermatozoa the patients were divided into three groups: group A--normal morphological features 0-5%; group B--6-10%; and group C--11-14%. A control group had normal morphological features greater than or equal to 15%. The fertilisation rate and number of embryos transferred was not significantly different in these groups. However, the pregnancy rate per embryo transfer was significantly different for groups A and B compared with group C and the control group (0% and 5.9% for groups A and B v. 13.9% and 18.3% for group C and the control group, respectively). It is concluded that when the normal sperm morphology is less than 11% the prospect of a pregnancy is poor.

Embryo Transfer↗
PubMed1987

The role of interleukin-2 in proliferative responses in vitro of T cells from patients after bone marrow transplantation. Evidence that minor defects can lead to in vitro unresponsiveness.

We have studied lectin-induced interleukin-2 (IL-2) production and proliferation of peripheral blood mononuclear cells from patients who had undergone a successful allogeneic bone marrow transplantation. Shortly after transplantation, the T cells show a decreased proliferative response and a decreased IL-2 production. However, addition to the culture of exogenous IL-2 does not result in restoration of the proliferative response, which indicates that the low proliferative response is not due to decreased IL-2 production alone. Longitudinal studies show a substantial variation between patients in the time in which the capacity to produce IL-2 is restored; however, in all patients there is a period in which IL-2 production is still diminished, but the proliferative capacity, as measured upon addition of exogenous IL-2 to the culture, is almost within the normal range. Also during this period, the proliferative response of the T cells can be restored by the addition of irradiated "feeder cells" obtained from the bone-marrow donors, as these cells secrete IL-2 without consuming it. Because peripheral blood samples from patients after bone marrow transplantation show great imbalances in the distribution of T4/T8 subpopulations, we have studied the influence of an artificially produced "reverse T4/T8" ratio on the proliferative response to mitogen and (allos-)antigen stimulation of healthy donor T lymphocytes. Even at very low proportions of T4 cells, normal responses were obtained in the proliferation assays with polyclonal mitogens. Only the response to soluble antigens, such as tetanus toxoid, was impaired. However, a low proportion of T4 cells resulted in a low IL-2 production so that, when IL-2 is a limiting factor due to intrinsic defects of patient cells, an inverse T4/T8 ratio can cause a nonresponsiveness in in-vitro assays.

Bone Marrow Transplantation↗
PubMedDate not supplied

In vitro decondensation of the human spermatozoan nucleus and image analysis. Quantitative data on the kinetics of in vitro decondensation of the human spermatozoan nucleus.

The authors subjected 14 human sperm samples to decondensation in vitro. They analyzed the images of a total of 9,681 objects as a function of time of decondensation. The discussion bears on the heterogeneity of the process of chromatin decondensation in human spermatozoa, on the influence of the zinc/fructose ratio in the seminal fluid and on the role of the period during which the spermatozoa are left in contact with the fluid.

Cell Nucleus↗
PubMed1977

In vitro secondary MLR. I. Kinetics of proliferation and specificity of in vitro primed responder cells.

We have examined the kinetics and specificity of secondary in vitro mixed lymphocyte reactions (MLR). With limited numbers of primed responder cells (PRC) in the presence of "excess antigen" it was possible to obtain proliferative responses that were proportional to the number of PRC initially placed in culture. The responding cells, after an initial lag period, seem to grow exponentially until day 3 of culture. The responses of PRC (with the strain combinations and culture conditions described in this report) seemed to be directed toward stimulator cell determinants whose expression was determined by genes in the I region of the MHC. In one case, the relevant incompatibilities could be further restricted to the I-A region. Although PRC responded best to stimulator cells sharing the I region with the priming stimulator cell, apparent cross-reactivity could be observed by restimulating PRC with stimulator cells that did not carry the MHC haplotype of the priming stimulator cell. The rate of proliferation (measured as 3H-thymidine incorporation) in these apparent cross-reactions was reproducible and comparable to the rate observed in response to the priming stimulator cell. It was possible, therefore, to estimate the proportion of PRC that reacted in the presence of third party stimulator cells compared to the response of these PRC to the priming stimulator cells. We have estimated that the response of A (B6) PRC against H-2d and H-2s haplotype stimulator cells is about half of the response of these PRC to H-2b, the priming stimulator cell.

Animals↗
PubMed1977

Some data concerning immune processes in concomitant tumor immunity experimental models. Comparative in vivo and in vitro investigations II. In vitro experiments.

The humoral and cellular immune status of C57BL/6 male mice and "R" male rats bearing MC-induced sarcomas were investigated in vitro, using 51Cr-releasing and mixed hemadsorption assays. Analysis was performed on mice subjected to concomitant tumor immunity (CTI) model experiments or bearing primary tumors of different sizes, that was done also in rats. Chromatographic fractions, assumed to contain tumor specific antigens, antibodies or antigen-antibody complexes were identified by their absorption capacity upon specially prepared syngeneic immune sera. Free antibody and antigen-antibody complexes, accompanied with a weak cell mediated immunity (CMI) were correlated with efficient CTI in 2--3% TW/TBW tumor bearers. Homoral immunity (HI) showed sometimes an important increase after challenge administration. High levels of free antigen and antigen-antibody complexes, lack of antibodies and CMI were correlated with CTI absence in huge tumor bearers, representing 30--37% of total body weight. Conditions determining variability of results reported by different authors and the possible mechanisms by which serum immune factor may impair the tumor bearer's immune status are discussed.

Animals↗
PubMed1975

Specific anti-tumor responses by cultured immune spleen cells. I. In vitro culture method and initial characterization of factors which block immune cell-mediated cytotoxicity in vitro.

Spleen cells from BALB/c mice which either bore syngeneic sarcomas or were normal controls were cultured in vitro. The culture supernatants of spleen cells from tumor-bearing mice inhibited (blocked) specific cell-mediated cytotoxicity to the tumor borne by the spleen donor. They also mediated specific antiserum-dependent cytotoxicity with control lymphoid cells. The appearance of blocking activity in culture supernatants was prevented by lysis of theta-positive spleen cells with antiserum and complement. The blocking activity was removed by passing culture supernatants through an anti-mouse immunoglobulin affinity column and was recovered in a 3 M NaSCN eluate of the column.

Animals↗
PubMed1975

[Inhibition of corneal metabolism by glucocorticosteroids. An in vitro study (author's transl)]?14Hemmung des Hornhautstoffwechals durch Glukocorticosteroide. Eine in vitro Studie.

Cortisone and its derivates demonstrates influence to the metabolism of connective tissue. In this in vitro-study the action of water soluble Dexamethason (Schering) to corneal tissue is quantitatively determined. Incorporation of radioactive sulfate into the glycosaminoglycanes and the sulfate-hexosamine-quotient of keratansulfate and chondroitinsulfate is pointed out. 1. A 2 times 10-7 M Dexamethason-concentration and 6 hours incubation time causes reducing of sulfate incorporation in the case of keratansulfate (I) about 94 per cent and chondroitinsulfate (II) about 89 percent compared to nontreated control. Increasing concentration of Dexamethason leads the inhibition of sulfate incorporation to 66 per cent (I) and 63 per cent (II) respectively. Removing the epithelium from the stroma before incubation the Dexamethason concentration and 6 h incubation time only 84 percent and 80 per cent radioactive sulfate is found in keratansulfate and chondroitinsulfate. An increasing Dexamethason concentration leads to inhibition of 55 per cent (I) and 46 per cent (II) respectively. 2. A comparable inhibition of sulfate incorporation is demonstrated with constant Dexamethason concentration and variable duration of incubation. A 1 hour incubation reduced incorporation of sulfate to 89 per cent for keratansulfate and 81 per cent for chondroitinsulfate. The 24 hours incubation inhibits incorporation to 69 per cent (I) and 65 per cent (II) respectively.

Animals↗
PubMed1991

Induction of experimental murine granuloma formation against Schistosoma japonicum eggs produced by in vitro ova deposition, in vitro tissue extraction, or lyophilization.

Fresh eggs, laid by Schistosoma japonicum adult worms in vitro or recovered from tissue after trypsin digestion, as well as non-viable lyophilized eggs were injected into mice via the cecal vein. The freshly laid eggs induced a marked, maximal reaction at 2 weeks after implantation. This reaction was indistinguishable from that seen early in naturally infected mice. Lyophilized eggs induced granulomas only one-tenth the size of those formed around freshly laid eggs. Maximal granulomatous reactivity was not seen until the 4th week after implantation and the intensity of cellular reactivity and associated histopathological change was much lower than that observed with freshly laid eggs. Reactions against live, tissue-extracted eggs were quantitatively and temporally intermediate between those observed against laid and those surrounding lyophilized eggs. The results suggests that these differences in granuloma formation are due to variable quantities of locally produced cytotoxic materials and/or antigen that stimulate immune reactions of different intensities.

Animals↗
PubMed1990

Chemical composition, in vitro protein digestibility and in vitro available iron of blue green alga, Nostoc commune.

Blue-green alga, Nostoc commune, contained moderate amounts of protein and iron. Its in vitro protein digestibility was 43.50%. The soluble and ionic iron from the alga was extractable to some extent at pH 1.5 but was not detectable at pH 8.0. The digestion by protease did not affect the iron detection. Heat processing at 100 and 120 degrees C failed to increase the digestibility and the content of available iron. The dietary fiber in the alga may be responsible for low protein digestion and low iron availability.

Biological Availability↗
PubMed1995

Bendazac decreases in vitro glycation of human lens crystallins. Decrease of in vitro protein glycation by bendazac.

Bendazac has been used as an anti-cataractogenic drug. It has been reported that this acts by preventing protein denaturation. In this study the ability of bendazac to inhibit in vitro glycation of human lens crystallins was evaluated. Possible effects of bendazac were detected by incubation of WS crystallins with the reducing sugars glucose and fructose. The efficiency of bendazac was evaluated by means of selected parameters including: browning, glycation (measured as tyrosine content) and specific NTP-fluorescence. The results showed clearly that bendazac (bendazac L-lysine and sodium) inhibits the early stages of protein glycation, as well as the formation of fluorescent advanced glycation products. Bendazac lysine (20 mM) proved to be more effective in inhibiting fluorescence development (67% inhibition) that the corresponding sodium salt (35% inhibition). No significant differences were found with respect to furosine levels; about 40% inhibition was produced with either bendazac lysine or sodium salt bendazac clearly inhibits glycation of human lens crystallins, as can be efficiently monitored by following specific changes in lens protein fluorescence. These results may constitute a new and relevant therapeutic approach to monitoring cataract development.

Adult↗
PubMed1981

In vitro culture of leukocytes from patients with sarcoidosis: in search of an "in vitro Kveim test".

Mononuclear cells from patients with sarcoidosis respond to Kveim tissue suspensions in vivo and from granulomas. We attempted to develop an in vitro Kveim test by adding Kveim material to monocytes and lymphocytes from patients with sarcoidosis and observing the cells in tissue culture. Sarcoid leukocytes were grown in culture with either Kveim suspensions (100 microgram/ml), control human spleen extract (100 microgram/ml) or no foreign antigen. After 7 to 9 days, we counted the number of cells adherent to glass, the number of cells with nucleoli, and the number of giant cells. Despite equal monocyte inocula, cultures of sarcoid leukocytes consistently had more cells adherent to glass than did cultures from normal donors regardless of whether Kveim, spleen, or no antigen was added to the cultures. There were no significant differences in giant cell formation or in the number of cells with nucleoli in the sarcoid compared with the control cultures.

Cell Nucleolus↗
PubMed1991

The spontaneous apoptotic cell death of normal human lymphocytes in vitro: the release of, and immunoproliferative response to, nucleosomes in vitro.

Nucleosomes released spontaneously in short-term culture from murine spleen cells have a significant immunoproliferative effect in vitro, including the stimulation of anti-DNA antibody responses. The present studies show that during short-term cultures, tonsil lymphoid cells also undergo spontaneous apoptosis revealed morphologically (electron microscopy) by the appearance of changes in nuclear chromatin, typical of apoptosis and similar to morphologic changes of apoptosis in cultured normal splenic lymphocytes. This process is followed by the release, in the greater than 30-kDa cell free supernatant fraction, of core histones (H2A, H2B, H3, H4) and low molecular weight DNA (approx 160 bp) constituents of nucleosomes. The greater than 30-kDa tonsil lymphocyte cell-free supernatant material containing the constituents of core nucleosomes, as well as the greater than 30-kDa supernatant fractions of tonsil cell lysates harvested at the same time, had a significant immunoproliferative effect on human or murine lymphocytes, increasing both DNA and immunoglobulin synthesis (protein A plaque-forming cells). Thus the release of immunoproliferative nucleosomes form dying human lymphoid cells provides an autocrine lymphocyte stimulatory network which may be important in immunoproliferative disorders and in normal cell turnover. Apoptosis in vivo may also provide a potential source for the circulating nucleosomal DNA identified in plasma in some systemic lupus erythematosus patients as well as contributing to increased polyclonal B lymphocyte stimulation and autoantibody responses in this disorder.

Cell Survival↗