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J S Lin

Publications and source records attributed to J S Lin.

At least 181 records · Page 10Linked to original sources
PubMed1986

[Role of hypothalamic histaminergic systems in the regulation of vigilance states in cats].

We have studied the effects of local injections of histaminergic and antihistaminic drugs on the sleep-waking cycle in the cat. Microinjections of alpha-fluoromethylhistidine (alpha-FMH), a specific inhibitor of histidine decarboxylase, in the ventrolateral posterior hypothalamus, where histamine-immunoreactive neurons have been recently identified, resulted in a significant decrease in wakefulness (W) and increase in deep slow wave sleep (SWS). On the other hand, microinjections of SKF-91488 (Homodimaprit), a specific inhibitor of histamine-N-methyltransferase, increased W and decreased SWS and paradoxical sleep (PS). Microinjections of histamine also produced an increase of W, while this effect was abolished by pretreatment with mepyramine, an H1-histamine receptor antagonist.

Animals↗
PubMed1986

[Histamine-immunoreactive neurons in the hypothalamus of cats].

The localization of histaminergic neurons in the cat brain was determined immunohistochemically with an antibody against histamine. We found that histamine-immunoreactive neurons are observed exclusively in the posterior hypothalamus of colchicine treated cats. The larger group of neurons was found in the ventrolateral part of the posterior hypothalamus, including the tuberomammillary nucleus. Histamine-positive neurons were also observed in the supramammillary area and adjacent posterior hypothalamic area, as well as in the peri- and premammillary regions. In addition, numerous histamine immunoreactive fibers were detected, not only in the posterior hypothalamus, but also in other brain areas, such as the preoptic area of the anterior hypothalamus.

Animals↗
PubMed1982

Complement-mediated killing of Ureaplasma urealyticum by antibody directed against components of the growth medium.

Many strains of Ureaplasma urealyticum were inactivated, in the presence of complement, by a control antiserum prepared in guinea-pigs against the uninfected culture medium used to grow ureaplasmas. This mycoplasmacidal activity of the control serum, unlike that of the specific antisera prepared against the organisms themselves, was removed by treatment with dithiothreitol or by absorption with the horse-serum component of the medium, suggesting that the activity was due to an antibody of the IgM class acting on horse-serum proteins that had become associated with the surface of the ureaplasmas. The mycoplasmacidal activity in the specific ureaplasma antisera appeared to be due mainly to antibody of the IgG class. A similar complement-dependent mycoplasmacidal antibody to U. urealyticum apparently active against serum components, was present in normal rabbit sera.

Antibodies, Bacterial↗
PubMed1980

Infection with Mycoplasma hominis in postpartum fever.

A follow-up of 535 patients after vaginal delivery showed that 9% had a fever of 37.7 degrees C or greater, and 2% had a fever of 38 degrees C or more, on two days. The commonest cause of both categories of fever was Mycoplasma hominis infection as defined by a fourfold or greater rise in mycoplasmacidal antibody titre. Among women for whom sera were available this agent caused 50% (14/28) of all fevers and 71% (5/7) of the higher fevers. Absence or low titre (< 1:8) of antibody against M. hominis was the strongest single predictor of otherwise unexplained fever (16/40 patients with low antibody titre were febrile vs 7/50 with high antibody titre, p < 0.01). Among women with absent or low antibody titres, both rise in titre of antibody to this organism and lochial colonisation by it were significantly associated with fever (p < 0.001, p < 0.025, respectively). Standard microbiological and clinical techniques identified probable causes in only 18% (5/28) of all fevers and 29% (2/7) of higher fevers. Patients who had postpartum infection caused by M. hominis remained in hospital 31% longer than the non-infected patients (4.57 vs 3.49 days, p < 0.001). Low antibody to and lochial colonisation with M. hominis occurred together in 17% of patients, who accounted for 71% of all higher fevers. Since these risk factors for postpartum fever can be identified before delivery, prophylactic measures applied selectively to women with these risk factors may prevent a large proportion of postpartum fevers and the excess hospital stay associated with them.

Adult↗
PubMed1980

Fourteen serotypes of ureaplasma urealyticum (T-mycoplasmas) demonstrated by the complement-dependent mycoplasmacidal test.

Previously, we found that strains of Ureaplasma urealyticum could be divided into 11 serotypes using the mycoplasmacidal (MC) method for serotyping. Subsequent study has shown that two pairs of these strains were sufficiently closely related to cause us to revise the typing scheme into nine distinct serotypes. Other investigators, using different methods to detect serotypic diversity, have found eight serotypes. We have now compared our nine strains with the eight prototype strains developed by Ford and Black, and we have used reciprocal MC titers of antisera for the comparison. Three pairs of strains from our group and the group prepared by Ford and Black were found to be serologically closely related or identical, leaving six serotypes in our series and five in the other series that were serologically unique. Thus 14 serotypes of U. urealyticum have been identified in these studies, and a 15th strain that is apparently serologically distinct from the others, has recently been described in Vancouver.

Serotyping↗
PubMed1980

An antigenic analysis for membranes of Mycoplasma hominis by cross-absorption.

Antigenic components at the outer surface membranes of seven serotypes of Mycoplasma hominis were analysed by the mycoplasmacidal reaction and the agglutination during growth reaction. Antibody absorbing capacities of the mycoplasma cells were compared with absorbing capacities of membranes. It was shown that serologically active membrane antigens were mainly heat-labile proteins. No major antigens common to all seven serotypes were detected and each strain had its own specific antigens at the cell surface. Results of analysis indicate that there is a complex antigenic structure exposed in M. hominis and that 7 to 14 cross-reacting antigens may be present at the outer surface in the different serotypes examined. Additional cross-reacting antigens, presumably inner membrane in origin and not exposed at the cell surface, were also demonstrable.

Antigens, Bacterial↗
PubMed1978

Serologic studies of human genital mycoplasmas: distribution of titers of mycoplasmacidal antibody to Ureaplasma urealyticum and Mycoplasma hominis in pregnant women.

Titers of mycoplasmacidal antibody to the human genital mycoplasmas Ureaplasma urealyticum and Mycoplasma hominis were determined using genital isolates from pregnant patients as antigens and comparing these isolates with the 11 prototypic reference strains for U. urealyticum and the seven reference strains for M. hominis. Virtually all titers that were detected with use of the patient's own isolates were detected by the 11 reference strains of U. urealyticum and by the seven reference strains of M. hominis. Serologic surveys of pregnant women who harbored either or both mycoplasmas in vaginal cultures indicated that antibody to M. hominis was found more commonly than antibody to U. urealyticum. It was demonstrated that significant postpartum rises in titers of antibody to M. hominis were correlated with the presence of these mycoplasmas in genital cultures. Postpartum rises in titer of antibody were particularly likely to occur in women with low titers of mycoplasmacidal antibody in serum at the time of delivery. Approximately 88% of the women who were colonized with M. hominis showed significant changes in titer of antibody to M. hominis throughout an apparently normal pregnancy; only 40% of the women who were colonized with U. urealyticum showed such changes in titers to U. urealyticum. Statistical analysis showed that mean log titers of antibody to both mycoplasmas at the first prenatal visit were significantly associated with the number of pregnancies experienced by these women.

Antibodies, Bacterial↗
PubMed1978

Isolation of Mycoplasma hominis from blood cultures in patients with postpartum fever.

Eight women with postpartum fever are presented in whom Mycoplasma hominis was isolated from cultures of their blood. Clinical disease consisted of a mild although often prolonged febrile illness, and all but one recovered without appropriate antimicrobial therapy. Five patients demonstrated elevated convalescent titers of mycoplasmacidal antibodies. The isolates of M. hominis were recovered from routine blood cultures in the diagnostic bacteriology laboratory using blind subcultures to blood agar plates. These cases lend support to the concept that endometritis with M. hominis is a cause of postpartum fever and suggest that these organisms may be recovered with increased frequency if minor changes in standard bacteriologic technique are introduced.

Bacteriological Techniques↗
PubMed1977

Etiology of nongonococcal urethritis. Evidence for Chlamydia trachomatis and Ureaplasma urealyticum.

Chlamydia trachomatis, Ureaplasma urealyticum (T-mycoplasma), and Hemophilus vaginalis have previously been considered possible etiological agents in nongonococcal urethritis (NGU). In this study, current C. trachomatis infection was confirmed by culture and (or) micro-immunofluorescence serology in 26 of 69 men experiencing afirst episode of NGU, and 1 of 39 with no urethritis. Serum IgM immunofluorescent antibody to chlamydia was demonstrated in 16 of 20 men with chlamydia culture positive NGU, and 3 of 39 with chlamydia culture negative NG, and none of 34 with no urethritis. 9 of 10 culture positive men with less than or equal to 10 days symptoms developed immunofluorescent antibody seroconversion in paired sera. U. realyticum was isolated significantly more often and in significantly higher concentration from first voided urine from chlamydia-negative cases of NGU than from chlamydia-positive NGU. Ureaplasmacidal antibody titers increased fourfold in six men, four of whom had negative cultures for for unreaplasma. H. vaginalis was isolated from c9 of 33 men with no urethritis and 2 of 69 with NGU. C. trachomatis is susceptible, and U. urealyticum is resistant to sulfonamides. A 10-day course of sulfisoxazole therapy produced improvement in 13 of 13 chlamydia-positive, unreaplasma-negative, and only 14 of 29 chlamydia-negative, unreaplasma-positive NGU cases (P less than 0.002). Thus, culture, serology, and response to therapy support the etiologic role of chlamydia in NGU. Quantitative culture and response to therapy suggest U. unrealyticum may cause many cases of chlamydia-netative NGU.

Adult↗