Biomedical subjects
Publications and source records attributed to Y Yang.
The title complex with the formula EuL3 x phen x H2O (phen=1, 10-phenathroline, HL=p-anisic acid) were synthesized and characterized by elemental analysis, molar conductivity, IR, UV, NMR etc.
The expression of cytokeratin (CK) mRNA for CK5, -8, -14, -16, and -19 was investigated in normal prostate, prostatic intraepithelial neoplasia (PIN) lesions, and invasive carcinoma using in situ hybridization. Protein localization was carried out in adjacent sections using immunohistochemistry and correlated with mRNA expression. Snap-frozen human prostate samples including 22 examples of normal glands, 20 cases of PIN lesions, and 12 cases of invasive carcinoma were examined. CK5 and -14 mRNA and protein were prominently expressed only in the basal cells of normal glands and PIN lesions. CK14 mRNA was absent in the luminal cells of the most of the PIN lesions but was seen at a low level in some PIN lesions. CK14 protein was not detected in any PIN lesion, suggesting that, if the cell that makes up the PIN lesions is derived from a basal cell, CK14 translation is depressed although a low level of CK14 mRNA may persist. CK8 mRNA and protein were constitutively expressed in all epithelia of normal and abnormal prostate tissues. CK19 mRNA and protein were persistently expressed in both basal and luminal cells of the tubular portion of normal glands as well as PIN lesions, but were expressed heterogeneously in both basal and luminal cells of normal alveoli. CK16 mRNA was expressed in a similar pattern as CK19, but CK16 protein was not detected either in normal or in abnormal prostate tissues. In conclusion, the expression of CK19 in PIN lesions is similar to its tubular expression and would support an origin of PIN lesions from this structure rather than the alveolar portion of the glands. The similar cytokeratin expression between PIN lesions and invasive carcinoma further supports the concept that PIN is a precursor lesion of invasive carcinoma.
BACKGROUND: Several studies have shown that some aspects of vision are impaired when exposed to higher than normal CO2 concentrations in air. The effect of moderately increased CO2 concentration on coherent motion perception, however, has not been studied. HYPOTHESIS: Studies in neurophysiology and cell biology have provided evidence that higher than normal CO2 concentration in air affects cell activities from the retina to the cortex, including the V1 area in the visual cortex. We predicted that motion perception may be impaired by moderately increased CO2, since the V1 area is a gateway for visual motion information processing. The purpose of the present work was to investigate the effect of 2.5% CO2 concentration in air on coherent motion perception. METHODS: Random dot cinematograms were generated by a computer and served as visual stimuli. A whole-room indirect calorimeter was used for the accurate measurement and control of CO2 concentration in air, and served as the experimental environment. A two-interval-forced choice (2IFC) psychophysical procedure was employed to obtain psychometric functions. RESULTS: For all three subjects, psychometric functions were shifted to the right when exposed to 2.5% CO2 in breathing air, compared to those using fresh air. CONCLUSION: This finding implies that human ability in detecting coherent motion can be temporally impaired when CO2 concentration in air is raised to 2.5%.
In previous studies, we found that single injections of the thyrotropin-releasing hormone analog TA-0910 dose-dependently reduced alcohol intake and preference in alcohol-preferring (P) and Fawn-Hooded (FH) rats over a 24-hr period of continuous access to alcohol and water. However, several consecutive daily injections of TA-0910 resulted in the development of tolerance to these effects. In the present study, we found that in a 5-hr limited-access schedule in which monkeys could select an aqueous alcohol solution (7.5% v/v) or tap water, single doses of TA-0910 (0.0625, 0.125, 0.25, 0.5, and 0.75 mg/kg), similar to those found effective in P and FH rats, reduced consumption of alcohol. In this protocol, tolerance to the attenuating effects of TA-0910 on alcohol intake was not evident after five consecutive once-daily doses of 0.5 mg/kg. Furthermore, it was shown that a single dose of 0.75 mg/kg TA-0910 did not significantly influence 24-hr water intake when water was the only available fluid, but did reduce the intake of a preferred solution of saccharin. These findings suggest that activation of brain thyrotropin-releasing hormone systems reduces alcohol intake in primates and that tolerance to this effect is not evident within 5 days under a limited access schedule.
A 62-year-old woman with hypocellular acute myelogenous leukemia experienced spontaneous remission after repeated episodes of severe infections. Transient surge of profuse blasts in the peripheral blood was observed prior to the occurrence of spontaneous remission. The duration of the spontaneous remission was relatively short, and the disease relapsed five months later. A second complete remission was achieved after chemotherapy with low-dose cytosine arabinoside. The patient finally died of relapsed leukemia after a second remission of three year duration. Possible mechanisms implicated in the occurrence of spontaneous remission in this patient are discussed.
Extracts of urine and serum from children with cholestatic liver disease were analyzed by fast atom bombardment (FAB) mass spectrometry. About half of all spectra showed a peak at m/z 657, compatible with the presence of a glucuronidated cholestenediol sulfate. Separation by ion exchange chromatography before and after solvolysis and treatment with beta-glucuronidase, combined with analyses by gas chromatography-mass spectrometry and FAB mass spectrometry with collision-induced dissociation, showed that the major compound responsible for the peak at m/z 657 was (24S)-24-hydroxycholesterol 3-sulfate, 24-glucuronide. The double conjugate of 27-hydroxycholesterol was also identified and double conjugates of cholestene- and cholestanetriols were also present. Semiquantitative analyses of the double conjugate of 24-hydroxycholesterol in patients whose FAB spectra showed a peak at m/z 657 indicated serum levels of 2-18 microM and a daily urinary excretion of 0.1-2.7 mumol/24 h. Eleven of 13 studied patients with a prominent peak at m/z 657 in the FAB spectra of their serum or urine either underwent liver transplantation or died. It is concluded that double conjugation of hydroxysterols with sulfuric and glucuronic acids can be an important metabolic pathway, particularly for (24S)-24-hydroxycholesterol. It is speculated that serious cholestatic liver disease may induce an increased formation and release of (24S)-24-hydroxycholesterol from brain (Lütjohann et al. 1996, Proc. Nutl. Acad. Sci. USA. 93: 9799-9804) with subsequent extracerebral conjugation with sulfuric and glucuronic acids.
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We have previously found that human chromosome 3 was fragmented in the course of in vivo tumor growth of monochromosomal human/mouse (A9 fibrosarcoma parent) microcell hybrids in SCID mice. Marker analysis of tumor cell lines has identified a regularly eliminated 7 cM segment on 3p21.3 referred to as the common eliminated region (CER). The same region is frequently affected by LOH in a variety of human carcinomas. The present study is a comparative chromosome painting, reverse painting, and PCR marker analysis of microcell hybrids (MCHs) that originally contained an intact chromosome 3 from two alternative donors, during and after four passages in SCID mice. We found regular elimination of 3p in parallel with preferential retention of 3q. In addition to CER on 3p, we can now define a common retained region (CRR) on 3q. It includes eight markers between D3S1282 (3q25-q26) and D3S1265 (3q27-qter) and spans approximately 43 cM. These observations are concordant with the frequent loss of corresponding 3p regions and the frequent retention, with occasional amplification, of 3q in several types of human tumors.
OBJECTIVE: To assess the awareness of AIDS, other sexually transmitted diseases (STDs), condoms, sources of health information and HIV-related societal risks among Dai villagers in southern Yunnan Province, China. SUBJECTS AND METHODS: In November-December 1994, a cross-sectional descriptive study, comprising a questionnaire-based survey and focus group discussions, was conducted in three Dai villages in Mengla county; a total of 177 Dai villagers were interviewed in the survey and eight focus group discussions were held. Ethnographic observations provided a composite picture of HIV risks in the area. RESULTS: Only 18% of respondents had heard of AIDS, and only 25 and 28%, respectively, had heard of STDs or condoms. Furthermore, among these more aware groups, the level of knowledge was low and misconceptions were common. An ability to understand the official language (Mandarin) was the most important predictor of awareness of AIDS, other STDs or condoms. The sources of information in the three Dai villages sampled included TV, videos, radio and magazines, but only TV and videos had a large audience. Even so, these media were mostly in Mandarin and were not used in AIDS education. Travel outside of China was frequent; most villagers (77%) had traveled to Laos and 9% had traveled to Thailand. Societal risks of HIV transmission, such as an increasing incidence of STDs and an active sex industry, were observed in this area. CONCLUSIONS: Dai villagers in southern Yunnan Province had an extremely low awareness and knowledge of AIDS, other STDs and condoms. Given the high mobility of ethnic villagers to neighboring countries in Southeast Asia and the societal risks of HIV transmission in this area, there is an urgent need to provide accessible education about AIDS and other STDs. Suggestions regarding such health education and the implications of HIV policy-making are discussed.
We have previously identified an approximately 7 cM long common eliminated region (CER), involving the 3p21.3 markers AP20R, D3S966, D3S3559, D3S1029, WI-7947, D3S2354, AFMb362wb9, and D3S32, in human chromosome 3/A9 mouse fibrosarcoma microcell hybrid (MCH) derived SCID mouse tumors. We now report the results of our more detailed analysis on 24 SCID mouse tumors derived from two MCH lines that originally carried intact human chromosomes 3. They were analyzed by fluorescence in situ hybridization (FISH) painting and PCR, using 24 markers covering the region between D3S1611 and D3S13235 at 3p22-p21.2. D3S32 and D3S2354 were regularly eliminated during in vivo tumor growth, whereas the other 22 markers, D3S1611, ACAA, D3S1260, WI-692, AP20R, D3S3521, D3S966, D3S1029, D3S643, WI-2420, MSTI. GNAI2, D3S1235, D3S1298, GLBI, WI-4193, D3S3658, D3S3559, D3S3678, WI-6400, WI-7947, and WI-10865, were regularly retained. We have defined a common eliminated region of approximately 1.6 cM (designated as CER1) inside the 7 cM CER described earlier. CER1 is flanked distally by D3S1029 and proximally by D3S643.
Pharmacological experiments were conducted to determine the neuronal mechanisms involved in the suppressive effects of the thyrotropin-releasing hormone analog TA-0910 on alcohol intake in alcohol-preferring (P) rats. We previously reported that single intraperitoneal injections of TA-0910 dose-dependently reduced alcohol intake in P rats without altering fluid or total calorie intake; however, after several consecutive, once-daily injections, P rats developed tolerance to the suppressive effects of TA-0910 on alcohol intake and cross-tolerance to like effects of the dopamine D2 agonist bromocriptine, but not to like effects of the serotonin uptake inhibitor fluoxetine. In the present study, rats were injected with vehicle or different doses of the D2 antagonist s(-)-eticlopride (0.01 to 0.05 mg/kg) or the D1 antagonist R(+)-SCH23390 (0.1 to 0.5 mg/kg) and 20 min later with TA-0910 (0.75 mg/kg). Alcohol and water intakes were measured at 2, 4, 6, and 24 hr, and food was measured every 24 hr. Both s(-)-eticlopride and R(+)-SCH23390 produced modest reductions in alcohol intake alone; however, only s(-)-eticlopride antagonized the suppressive effect of TA-0910 on alcohol intake. In related experiments, it was confirmed that the dopamine D3 agonist 7-hydroxy-N,N-di-n-propyl-2-aminotetralin reduced alcohol intake in P rats, and it was found that tolerance to this effect did not develop during or after seven consecutive once-daily injections. Furthermore, this effect of 7-hydroxy-N,N-di-n-propyl-2-aminotetralin was not diminished in rats made tolerant to the effect of TA-0910 on alcohol intake. These data, those of previous studies, and recent preliminary findings support involvement of dopamine D2, but not D1 or D3 receptors in mediating the suppressive effect of TA-0910 on alcohol intake of P rats.
Random amplified polymorphic DNA(RAPD) has been used in analyzing 13 winter worm, summer grasses (Cordyceps sinensis [Berk.], Sacc.) from 5 areas in Qingzang plateau. For 19 arbitrary primers, each individual showed about 65 RAPD markers. The genetic distances among those 13 winter worm, summer grasses were correlated to their geographic distances. Molecular phylogenetic tree constructed by UPGMA and NJ suggested that 13 winter worm, summer grasses could be divided into 3 clusters: east cluster, north cluster and middle cluster, in consistence with their origins and genetic divergence among different clusters. Furthermore, our results implied that the RAPD markers of winter worm, summer grasses showed a geographic specificity and could be a better genetic marker in studying genetic diversity and phylogeny of winter worm, summer grasses.
BACKGROUND: Lymphomas occurring in nasal cavities and paranasal sinuses are uncommon neoplasms in Western, but are reported to be higher in Oriental, countries. A retrospective study was performed to analyze the clinical and pathological characteristics of sinonasal lymphomas/polymorphic reticulosis at Taichung Veterans General Hospital during a 14-year period. METHODS: At Taichung Veterans General Hospital, 37 patients with sinonasal lymphomas (including three patients with polymorphic reticulosis) were seen from November 1982 through September 1996. Excluding three patients without sufficient data, a total of 34 patients with their clinical records were reviewed. Clinical information regarding characteristics of the tumors, histological studies, treatment modalities and follow-up was collected for analysis. RESULTS: The 34 patients who underwent review showed a male-to-female ratio of 2.1:1. Median age was 60 years (range 13-83 years). The most common symptoms were nasal obstruction, nasal discharge/rhinorrhea and epistaxis. Median duration of symptoms at the time of diagnosis was two months. The most frequently involved sites were nasal cavities (right more than left side). There were 31 non-Hodgkin's lymphomas and three polymorphic reticuloses. The pathological classifications revealed 13 diffuse large cell lymphomas, 14 diffuse mixed small and large cell lymphomas and four pleomorphic T-cell lymphomas. Of the 21 adequately staged patients, 13 patients were in stage I; four, stage II; two, stage III and two, stage IV. The immunophenotypic study was performed in 20 patients. Eighteen (90%) of them were T-cell lymphomas and only two cases (10%) derived from B-cell. Though approach to therapy and follow-up periods varied during the time period covered by this study, the differences in survival according to treatment modalities were not statistically significant. The follow-up period ranged from 9 days to 130 months. The mean survival was 84.2 months. The overall five-year survival rate was 63%. CONCLUSIONS: The majority of the cases here were T-cell lymphomas. Most histologic grading by Working formulation belonged to the intermediate grade. Optimal treatment for such a group of patients still has no consensus, but adequate local control is important. If diagnosed and treated early, primary sinonasal lymphomas can be associated with a favorable outcome even with local treatment alone.
OBJECTIVE: To evaluate long-term efficacy of percutaneous transluminal coronary angioplasty (PTCA) and the factors affecting its efficacy in Chinese patients. METHODS: Two hundred and twenty-nine patients who underwent successful PTCA in this institution were followed-up by direct interview or letters. The rate of follow-up was 95%. The period of follow-up were 0.5-8.4 (with mean of 2.3 +/- 1.8 years). RESULTS: Angina Pectoris recurred in 76 (33.2%) of the patients. Cox regression analysis revealed that the relative risk of recurrence of angina pectoris was increased among the patients with triple vessel disease and with history of hypertension. During the period of follow-up, 2 (0.9%) patients died, 6 (2.6%) had non-fatal acute myocardial infarction, 4 (1.7%) had coronary artery bypass graft surgery and 29 (12.7%) had repeat PTCA. The cardiac event-free survival rate calculated by Kaplan-Meier method was 84.8% at the first year and 70.5% at the eighth year. Cox regression analysis revealed that there were positive correlation between the relative risks of cardiac events and stenosis of lesions before PTCA and residual stenosis of LAD after PTCA. CONCLUSION: The long-term efficacy of PTCA in Chinese patients was good. The results of this study suggest that to decrease the residual stenosis of LAD during procedures could probably decrease the relative risk of cardiac events during follow-up.
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OBJECTIVE: To study the prevalence of Chlamydia trachomatis (CT) and Ureaplasma urealyticum (UU) infection in spontaneous abortion patients. METHODS: CT and UU in aborted tissues were determined by polymerase chain reaction (PCR) technique in 45 spontaneous abortion patients (abortion group) and 25 artificial abortion cases (control group). RESULTS: The detective rate of CT and UU was 42.2% and 33.3% respectively in the abortion group. As compared with the control group significant difference (P < 0.01, P < 0.025) was shown. The detection rate of mixed CT and UU is 8.9%. CONCLUSION: CT and UU are important infection factors which may cause spontaneous abortion. PCR examination of the aborted tissue can submit an accurate, rapid microorganic diagnosis of CT and (or) UU infection.
This article introduces a new electrocardiogam telephone transmitting and central ambulatory monitoring (receiving) system, and a device used for monitoring and transmitting the user's electrocardiogram. We also give some detailed discussion about the real time the flow display of ECG, and the signal preprocessing method based on the design of optimum FIR linear phase digital filter for the detection of QRS complexes.
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