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Biomedical subjects

J S Lin

Publications and source records attributed to J S Lin.

At least 163 records · Page 9Linked to original sources
PubMed1991

Myelodysplastic syndrome: a study of prognostic factors.

Forty-three patients with myelodysplastic syndrome (MDS) were retrospectively analyzed for its prognostic factors. We evaluated the relationship of the clinical, biochemical, and hematological data, as well as colony-forming unit myeloid (CFU-C) culture, Bournemouth score, modified Bournemouth score, and modified Dutcher score to the prognosis. The median age was 65 years. Eighteen patients had refractory anemia (RA), 4 had refractory anemia with ringed sideroblasts (RARS), 15 had refractory anemia with excess blasts (RAEB), 2 had refractory anemia with excess blasts in transformation (RAEB-t), and 4 had chronic myelomonocytic leukemia (CMMoL). The median survival of all patients was 482 days. The median survival for each subtype was as follows: RA, 628 days; CMMoL, 350 days; RAEB, 240 days; RAEB-t, 90 days. For RARS, no data have yet been obtained, because only one out of 4 patients with RARS has died. We subdivided all patients into two groups: one group included patients with RA or RARS and the other group included patients with RAEB, RAEB-t or CMMoL. The former group had a median survival of 677 days and the latter group 240 days, p = 0.0035. In the former group, 3 out of 22 patients (13.6%) developed acute myeloid leukemia (AML), as compared to 8 out of 21 patients (38.1%) in the latter group, p = 0.0661. Twenty-five of the 43 patients died: 10 from AML and 15 from infection and/or bleeding.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

HIV, HBV and HCV seropositivity in hemophiliacs.

Eleven cases of severe type hemophiliacs who had received long-term factor VIII injections were tested for the serological markers of human immunodeficiency virus (HIV), hepatitis B virus and hepatitis C virus (HCV). The period of factor VIII concentrate injections ranged from 2 to 32 years. The seropositive rates of HIV and HCV were 9/11(82%) and 11/11(100%), respectively. The seropositive rate of hepatitis B surface antigen was only 1/11(9%), while the seropositive rates of antibody to hepatitis B core antigen and antibody to hepatitis B surface antigen were 9/11(82%) and 7/11(64%), respectively, Although the patients had no symptoms related to acquired immunodeficiency syndrome, they were noted to have inverted helper/suppressor T-lymphocyte ratio, suggesting that hemophiliacs with long-term factor VIII injections have a high incidence of HIV and HCV infection, with immunological aberration.

Adult↗
PubMed1991

[The property of filamentous hemagglutinin of Bordetella pertussis].

For the purpose to clarifying the biologically active substance of B. pertussis, we prepared the filamentous hemagglutinin (FHA) from culture supernatant of the strain Tohama phase I and purified it through chromatography columns of hydroxylapatite, fetuin-Sepharose 4B and Sepharose CL 6B. There are several bands appeared in the polyacrylamide gel after SDS-PAGE, especially between 98 kD and 210 kD. The amount of 210 kD component is not proportional to hemagglutination (HA) activity of FHA among five different lots. Irons et al. reported that FHA preparation degraded the 220 kD and 210 kD polypeptides during the storage would be reduced the specific HA activity. Our result pointed out that the HA activity of purified Foffdid not relate to 210 kD component only. For the quality control of FHA purity in the B. pertussis acellular vaccine, we suggest that it would be necessary to test both HA titer and SDS-PAGE results.

Adhesins, Bacterial↗
PubMed1991

Stomach and duodenal alcohol and aldehyde dehydrogenase isozymes in Chinese.

Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) isozyme phenotypes were determined in surgical and endoscopic biopsies of the stomach and duodenum by agarose isoelectric focusing. gamma-ADH was found to be the predominant form in the mucosal layer whereas beta-ADH was predominant in the muscular layer. Low-Km ALDH1 and ALDH2 were found in the stomach and duodenum. High-Km ALDH3 isozymes occurred only in the stomach but not in the duodenum. The isozyme patterns of gastric mucosal ALDH2 and ALDH3 remained unchanged in the fundus, corpus, and antrum. The stomach ALDH3 isozymes exhibited a Km value for acetaldehyde of 75 mM, and an optimum for acetaldehyde oxidation at pH 8.5. Since the Km value was high, ALDH3 contributed very little, if any, to gastric ethanol metabolism. The activities of ALDH in the gastric mucosa deficient in ALDH2 were 60-70% of that of the ALDH2-active phenotypes. These results indicate that Chinese lacking ALDH2 activity may have a lower acetaldehyde oxidation rate in the stomach during alcohol consumption.

Adult↗
PubMed1990

Involvement of histaminergic neurons in arousal mechanisms demonstrated with H3-receptor ligands in the cat.

The effects of histamine H3-receptor ligands on sleep-waking parameters were studied in freely moving cats. Oral administration of (R)alpha-methylhistamine (alpha MHA), a H3-agonist, caused a significant increase in deep slow wave sleep while that of thioperamide, a H3-antagonist, enhanced wakefulness in a marked and dose-dependent manner. The arousal effects of thioperamide were prevented by pretreatment with alpha MHA or mepyramine, a H1-receptor antagonist. The findings support the hypothesis that the histaminergic neurons are critically involved in arousal mechanisms and suggest that H3-receptors play an active part in these mechanisms by regulating histamine transmission.

Animals↗
PubMed1990

[Diagnostic application of immunohistochemistry in pleomorphic sarcomas].

Eighteen cases of pleomorphic sarcoma diagnosed or supposed as rhabdomyosarcomas (RMS) and fourteen cases of other soft tissue lesions were stained with five specific antisera (myoglobin, desmin, alpha-1-antitrypsin, Lysozyme, and S-100) by peroxidase antiperoxidase method. The immunohistochemical findings indicated that the majority of the pleomorphic sarcomas (11/18) had to be reclassified as malignant fibrous histiocytoma (MFH), and pleomorphic RMS was indeed rare in adults over the age of 30 years. In this MFH group, desmin was present in all but 3 cases (8/11), supporting that MFH is a tumor originated from mesenchymal cells other than histiocytes. The success of using immunohistochemistry for making pathologic diagnosis depends upon rational application of panels of antibodies. The diagnostic features of pleomorphic sarcomas in routine or special stains are discussed.

Adolescent↗
PubMed1989

Type B monoamine-oxidase-containing cells and fibers in the cat hypothalamus demonstrated by an improved enzyme histochemical method.

The present study, using a diaminobenzidine (DAB)-coupled peroxidation method, examined the distribution and morphological characteristics of neuronal structures containing type B monoamine oxidase (MAO-B) in the cat hypothalamus. Large and intensely stained, distinctive MAO-B-positive cells, multipolar and with long dendritic arbors, were principally distributed in the ventral hypothalamus extending from A7 to A12.5 of the Horsley-Clarke plane. These cells were located caudally in the ventral surface of the brain including the tuberomamillary nucleus (TM) and the region surrounding the mamillary nuclei. Rostrally, they were aggregated in the area surrounding the fornix, particularly in the lateral perifornical region, and dispersed in the anterior mamillary nucleus, lateral hypothalamic area (HLA), and the medial tip of the entopeduncular nucleus. The most rostral positive cell group was identified in a narrow space between the optic tract and the entopeduncular nucleus at the A12.5 level. In addition to these large cells, the present study disclosed the presence of "small" to "very small" MAO-B-positive cells in the area surrounding the mamillary recess and the lateral part of the caudal arcuate nucleus. Distinct MAO-B-stained fibers were identified in all regions of the hypothalamus. A large number of thick labeled fibers were observed in the ventral hypothalamus including the TM and premamillary nucleus and posterior and lateral hypothalamic areas. A dense network of MAO-B-positive terminal-like fibers was observed in the dorsomedial nucleus where very small labeled cells were scattered. Many intensely stained thick and straight fibers were seen running ventrolaterally in the anterior part of the HLA and in the narrow space between the entopeduncular nucleus and optic tract. In the area of the tuber cinereum and the ventral part of the HLA, there were many positive fibers cut transversely, possibly projecting to the more anterior parts of the brain such as the diagonal band of Broca or septal nuclei.

Animals↗
PubMed1989

A critical role of the posterior hypothalamus in the mechanisms of wakefulness determined by microinjection of muscimol in freely moving cats.

In order to determine critical sites within the hypothalamus responsible for the induction and maintenance of wakefulness (W), we performed microinjections of muscimol, a potent gamma-aminobutyric acid (GABA) agonist, in various lateral hypothalamic regions of freely moving cats. We found that bilateral injections of a small amount of muscimol (0.1-1.0 micrograms/0.5 microliters) in the preoptic and anterior hypothalamus and rostral mesencephalic tegmentum resulted in increased vigilance and insomnia. In contrast, microinjections of muscimol in the middle and anterior parts of the posterior hypothalamus induced long-lasting behavioral and electroencephalographic signs of sleep with short latency. The hypersomnia was characterized by a significant increase in both light and deep slow wave sleep (SWS), and a nearly complete suppression of paradoxical sleep (PS). Animals with muscimol microinjections in the ventrolateral part of the posterior hypothalamus, however, exhibited increased SWS followed by a significant increase in PS. When injected into the posterior hypothalamus of insomniac cats pretreated with p-chlorophenylalanine (PCPA), muscimol induced not only SWS but also PS with short latency. The present data thus support the hypotheses that the posterior hypothalamus plays a critical role in the mechanisms of W and that sleep might result from functional blockade of the hypothalamic waking center.

Animals↗
PubMed1989

Small-angle X-ray scattering studies of fibrin film: comparisons of fine and coarse films prepared with thrombin and ancrod.

Measurements of small-angle x-ray scattering have been made on films prepared from fine and coarse (i.e., formed at high and low, respectively, pH and ionic strength) clots of bovine fibrin by osmotic shrinkage or compression in one dimension. Intensity profiles were obtained with pinhole geometry on films stretched up to a stretch ratio of 1.43. In unstretched coarse films, repeat spacings were seen at about 245, 120, and 77-80 A. These peaks can probably be identified with the first, second, and third orders of the well-known fibrin repeat of 225 A. In unstretched fine films, only the 77-80 A spacing was seen. In this case, the first two orders may be weak because the half-staggered arrangement of monomer units giving rise to the 225 A reflection is not reinforced by lateral aggregation of protofibrils; the third order may be strong since the molecular subdomains appear to divide the repeat roughly into thirds. After stretching, the 77-80 A spacing persisted in the meridional direction but almost disappeared in the equatorial. Experiments on unstretched films prepared with ancrod substituted for thrombin gave similar results.

Ancrod↗
PubMed1989

Inhibition of human neutrophil NADPH oxidase by Chlamydia serovars E, K, and L2.

The effects of Chlamydia trachomatis (serovars E, K, and L2) on human neutrophil activation were examined with respect to the organisms both as primary agonists and as agents that modulate cell responses to a second stimulus. Unopsonized chlamydiae alone, at ratios of 1.5 to 100 organisms per cell, failed to elicit changes in intracellular calcium or membrane depolarization or to stimulate the respiratory burst or degranulation during 60 min of incubation. Each of these functions except the respiratory burst was also normally activated when chlamydia-infected neutrophils were subsequently stimulated with formylmethionyl leucine phenylalanine or phorbol myristate acetate; the respiratory burst was inhibited 30 to 65%. Inhibition was dependent on live organisms and was maximal within 5 min of incubation. The organisms had no effect on the superoxide (O2-) assay, and the site of chlamydial inhibition was determined at the level of the NADPH oxidase itself, not at an intermediate step in the activation cascade. The mechanism of enzyme inactivation could not be determined. These results show that unopsonized chlamydiae do not elicit responses from infected neutrophils and suggest that microbicidal mechanisms other than those dependent on elaboration of toxic oxygen-derived species are required to inactivate chlamydiae.

Calcium↗
PubMed1989

Lung alcohol and aldehyde dehydrogenase isoenzymes in Chinese.

Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) isoenzyme phenotypes were determined in 53 surgical lung specimens by isoelectric focusing. ADH isoenzymes containing beta subunits, but no alpha, gamma or pi subunits, were found present in human lungs. Ninety percent of the lung specimens exhibited a pH-optimum for ethanol oxidation at pH 8.5, instead of 10.5 which is usual among Caucasians. The homozygous ADH2 2-2 phenotype was found to be 60%, and the heterozygous ADH2 2-1 phenotype, 30%. The remaining 10% of the lungs, exhibiting a pH-optimum 10.5, was homozygous ADH2 1-1 phenotype. Accordingly, the gene frequencies of the alleles ADH2(2) and ADH1(2) were calculated to be 0.75 and 0.25, respectively. Fifty-five percent of the 53 lungs examined possessed both the activities of ALDH I and ALDH II isoenzymes, whereas 45% lacked the ALDH I activity. The ADH activities in homogenate supernatants of the lungs with phenotypes ADH2 2-2 or ADH2 2-1 were considerably greater than those with ADH2 1-1 phenotypes. The ALDH activities were significantly higher in the ALDH I-positive lungs than in the ALDH I-negative groups. The implications of these distributions of lung ADH and ALDH isoenzyme composition and activity among Orientals for ethanol metabolism and toxicity are discussed.

Adult↗
PubMed1989

Mapping of cholinoceptive brainstem structures responsible for the generation of paradoxical sleep in the cat.

In order to determine the cholinoceptive brainstem structures critical for PS generation, we investigated the effect on PS induction of the injection of a small dose and volume (0.4 microgram/0.2 microliter) of the cholinergic agonist carbachol in the following caudal brainstem structures: 1) the caudal mesencephalic reticular formation, especially the nucleus pedunculopontinus pars compacta or X area; 2) the mediodorsal pontine tegmentum, in particular the nuclei locus coeruleus (LC), locus coeruleus alpha (LC alpha), peri-locus coeruleus alpha (peri-LC alpha) and laterodorsalis tegmenti (Ldt); 3) the pontine; and 4) bulbar gigantocellular (FTG) and magnocellular tegmental fields (FTM). We found that the only brainstem area from which a high amount of PS was induced by carbachol applications with short latencies, less than 5 minutes, is the mediodorsal pontine tegumentum, namely the LC alpha and peri-LC alpha, where ChAT-and TH- immunoreactive neurons are intermingled. Injections in an area immediately ventral to the peri-LC alpha induced physiological states resembling PS but lacking certain electrophysiological (PS-like) and behavioral components of PS (dissociated states I and II). The weak PS induction following carbachol administration in the anteromedial part of the FTG was due to the spread of the drug toward the efficient site since the latencies to PS onset were in the range of 20 to 60 minutes. No effects on PS generation were obtained after carbachol microinjections in the LC and the laterocaudal part of the FTG, while carbachol injections in the X area or in the bulbar FTG or FTM resulted in the increase of waking and the decrease of PS. In addition to these effects on PS induction, we also found that carbachol induced: 1) stereotyped PGO-like bursts when injected in the ventral part of the FTG and the rostral part of the FTM, 2) postural atonia with very short latencies, less than two minutes, when injected in the LC alpha and peri-LC alpha; and 3) hippocampal theta waves of 3-5 Hz persisting during light slow wave sleep (S1) when injected in and around the LC alpha and peri-LC alpha and in some points of the mediocaudal part of the FTG. These results support the hypothesis that PS is generated by highly localized neuronal populations and suggest that the mediodorsal pontine tegmentum (namely the nuclei LC alpha and peri-LC alpha) may represent a cholinoceptive PS generator.

Action Potentials↗
PubMed1988

Evidence for histaminergic arousal mechanisms in the hypothalamus of cat.

Polygraphic 23-hr recordings were carried out in 25 adult cats in order to examine the effects of both systemic and local injections of various histaminergic and antihistaminergic drugs on sleep-waking cycles. alpha-Fluoromethylhistidine (alpha-FMH), a specific inhibitor of histidine decarboxylase, when injected intraperitoneally at a dose of 20 mg/kg, induced a significant increase in deep slow wave sleep (S2) and a decrease in wakefulness (W), without modifying light slow wave sleep (S1) and paradoxical sleep (PS). Intraperitoneal injections of mepyramine (1 mg and 5 mg/kg), a well-known histamine H1-receptor antagonist, increased deep slow wave sleep and decreased wakefulness, as well as paradoxical sleep. Bilateral injections of alpha-FMH (50 micrograms/1 microliter) into the ventrolateral posterior hypothalamus, where histamine immunoreactive neurones have been recently identified, resulted in a significant decrease in wakefulness and increase in deep slow wave sleep. Similarly, injections of mepyramine (120 micrograms/1 microliter) in the same structures caused a significant decrease in wakefulness and an increase in deep slow wave and paradoxical sleep as well. In contrast, local injections of SKF-91488 (50 micrograms/1 microliter), a specific inhibitor of histamine-N-methyltransferase, led to a significant increase in wakefulness and decrease in both slow wave sleep (SWS) and paradoxical sleep. Injections of histamine, at doses of 5, 30 and 60 micrograms/1 microliter, also increased wakefulness and decreased slow wave sleep dose dependently, while these effects were completely blocked by pretreatment with mepyramine. The results suggest that histaminergic systems in the hypothalamus play an important role in arousal mechanisms and their actions are mediated through H1-receptors.

Animals↗
PubMed1988

[Peripheral nerve tumor with rhabdomyosarcomatous differentiation (malignant "triton" tumor)--report of 3 cases].

In this paper, 3 cases of malignant "triton" tumor are reported. By special stain, immunohistochemistry and electron microscopy, coexistence of rhabdomyoblasts and Schwann's cell elements was demonstrated. Case 1 was associated with von Recklinghausen disease; in case 3, the tumor developed within a nerve; both had background of malignant schwannoma. Case 2 was a girl with congenital giant pigmented nevus. Her tumor was composed predominantly of rhabdomyoblasts element but by immunohistochemistry, it was confirmed that her tumor also occurred within a nerve. The criteria of diagnosis, differential diagnosis and histogenesis are discussed.

Adolescent↗
PubMed1986

Transport abnormalities from single-breath dynamics of Ar, CO2 and O2.

A model framework is developed for analyzing non-invasive measurements of Ar, CO2, O2, and lung volume during a single exhalation from healthy and diseased lungs. The objective is to distinguish ventilation inhomogeneity from gas-exchange limitations associated with alveolar-capillary transport and processes within the blood. Several practical, quantitative indices are compared to provide distinction and physiological interpretation in terms of rate-determining transport processes. Some indices arise from a model in which the composition in the alveolar space differs from that of the exhaled gas. Other indices are computed from the effective dead-space volumes for Ar, CO2, and O2. Ventilation inhomogeneity is accounted for by the Ar dynamics. Values of these indices were computed from experiments with human subjects having normal lungs, restrictive pulmonary disease, or chronic obstructive pulmonary disease. These three groups are clearly distinguished by a pair of indices: one reflects ventilation inhomogeneity, while the other reflects dysfunction associated with the alveolar-capillary transport and capillary blood flow and distribution.

Airway Obstruction↗
PubMed1986

Arginine deiminase of Mycoplasma hominis: cytoplasmic and membrane-associated forms.

Membrane and cytoplasmic fractions of Mycoplasma hominis inhibited the multiplication of this mycoplasma. Arginine deiminase (EC 3.5.3.6), isolated from both fractions, reproduced the inhibition. The purified cytoplasmic deiminase had a subunit Mr of 49,000, a specific activity of 53 units (mg protein)-1 and an A280/A260 ratio of 1.76. The membrane-associated enzyme had an identical Mr but lower values for specific activity [39 units (mg protein)-1] and the A280/A260 ratio (1.46). In experiments in vitro, recent clinical isolates of M. hominis produced less arginine deiminase, but grew faster than the laboratory reference strain PG 21. In addition, other growth inhibitory components associated with membrane preparations were detected in recent clinical isolates but were absent from strain PG 21.

Cell Membrane↗