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Y Guo

Publications and source records attributed to Y Guo.

At least 469 records · Page 26Linked to original sources
PubMed1997

Analysis of epitope structure of PSP94 (prostate secretory protein of 94 amino acids): (I). Immuno-dominant and immuno-recessive area.

PSP94 is a potential biomarker for evaluating patients with prostate carcinoma. We have systematically studied the epitope structure of PSP94 by using a polyclonal antibody against human PSP94. Results of peptide mapping and ELISA tests of dose response to rabbit antiserum against human PSP94 protein showed that only the N-terminal peptides (N30 and M23) are immunoreactive while all the synthetic peptides (C28, C10) located closer to the C-terminus are completely devoid of antigenic activity with the polyclonal antibody. These results were confirmed by analysis of reciprocal competitive binding of PSP94 polyclonal antibody by the N-terminal peptides (N30 and M23) v. either recombinant GST-PSP94 fusion protein, purified recombinant PSP94, or natural PSP94 protein. To further delineate the antigenic activity of the N- and C-termini, we have also expressed N- and C-terminal half of the whole PSP94 (each 47 peptides) using the E. coli GST expression system. The recombinant N47/C47 peptides were released by thrombin cleavage from the GST fusion protein and characterized by Western blotting experiments. Dose response of the recombinant GST-PSP-N47 and -C47 peptides to PSP94 polyclonal antibody showed differential binding activities. Competitive binding of these recombinant N47/C47 proteins against the GST-PSP94 protein demonstrates that the polyclonal antibody has a higher affinity for the N47 peptide than the C47 peptide. Based on the immunological studies of both synthetic peptides and recombinant PSP94- N/C terminal proteins, we propose an epitope structure of human PSP94 with an immuno-dominant N-terminus and an immuno-recessive C-terminus.

Amino Acid Sequence↗
PubMed1997

Analysis of epitope structure of PSP94 (prostate secretory protein of 94 amino acids): (II). Epitope mapping by monoclonal antibodies.

PSP94 has shown potential to be a serum biomarker for evaluating prostate cancer. Studies of the epitope structure is crucial for this endeavour. In this article, we have used 15 different monoclonal antibodies (MAb) to analyse the epitope structure of PSP94 and to compare with the results obtained from our previous work using polyclonal antibody and recombinant PSP94. Firstly, we determined the relative activities of the 15 MAb population by direct and competitive ELISA. The two predominant MAbs (MAb PSP-6 and -19) in 15 MAbs were selected for further studies of the epitope structure. By comparing the binding activities of recombinant GST-PSP94 and natural PSP94 with MAbs, and by comparing their affinity with MAbs in an in vitro denaturing experiment, PSP94 was shown to have a similar, prevalently linear epitope structure as we demonstrated by polyclonal antibody. Using recombinant GST fusion protein with PSP94 and with each half of the N- and C-terminal 47 amino acids (GST-PSP-N47/C47) in E. coli cells, the different epitopes recognized by 15 monoclonal antibodies were delineated and the polar distribution of the epitope structure of PSP94 was characterized. Results of direct ELISA of recombinant N47 and C47 and their competitive binding against natural PSP94 (competitive ELISA) showed that the N- and C-termini represent the immuno-dominant and immuno-recessive area separately. A majority of the monoclonal antibodies (12/15) showed preferential binding of the N-terminal sequence of the PSP94 protein. Using GST-PSP-N47 as a standard protein, an epitope map of the 15 monoclonal antibodies was obtained. The results of this study will help to define the clinical utility of PSP94.

Animals↗
PubMed1997

Engineering factors affecting the granulation of sludge in the UASB reactor.

The influence of inoculum sludge involving different microbial populations, different modes of stream flow and different flow rates in a bioreactor on the granulation of sludge was studied. In the granulation process there were four periods: formation of microbial floccus, formation of subcore, growth of subcore, and maturity of granules. The production of microfloccus could be attributed to acid-forming bacteria. The hydrodynamic momentum transfer caused by moving phases and the hydraulic shear effect are the crucial factors affecting the formation of the subcore. For this a new concept-the lowest limited flow rate-is proposed, i.e., the lowest flow rate to form an expanded sludge bed. A sufficient feed rate (higher than the lowest flow rate), an appropriate sludge load, and an equal distribution of feed, as well as a suitable alkalinity in the medium are the essential factors for the scaling-up and process-control of the UASB reactor.

Anaerobiosis↗
PubMed1997

[Prognosis and prognostic factor analysis epithelial ovarian cancer].

OBJECTIVE: To investigate the prognosis change and prognostic factors of advanced epithelial ovarian cancer in recent over twenty years. METHODS: One hundred and fourty patients with advanced epithelial ovarian cancer were analyzed. They were divided into two groups based on their operation time. 56 patients operated before Jan. 1980 were included in the first group, and the other 84 patients in the second group. Kaplan-Meier survival curves of the two groups were calculated, and Cox model was used to evaluate the prognostic factors of the disease at univariate and multivariate levels using SPSS and SURVCALC software. RESULTS: There was no pathological difference in between the two groups, but the patients in the second group received more aggressive chemotherapy. The overall 1-, 2-, and 5-year survival rates were 61.2%, 32.1%, and 8.5%, respectively. In the first group they were 42.3%, 29.6% and 4.5% respectively and in the second group 69.3%, 36.2%, and 11.2% respectively. The prognosis of the patients in the second group was better than that in the first group, P < 0.05. Univariate analysis revealed that stage, grade, residual tumor size and chemotherapy were significant predictors of patients' outcome. COX regression analysis identified that they were all independent prognostic factors. The patients with advanced, low grade, residual tumor (> 2 cm) had poor prognosis. The prognosis of the patients who received equal or more than four, especially six cycles combined chemotherapy was improved. CONCLUSION: The prognosis of the patients with advanced ovarian cancer has improved in recent over 10 years, higher optimal cytoreductive rate and equal or more than six cycles combined chemotherapy are important measures for the better prognosis of advanced ovarian cancer.

Adenocarcinoma, Mucinous↗
PubMed1997

[Estrogen and progesterone receptors in endometrial carcinoma].

OBJECTIVE: To study the relationship between estrogen receptor (ER) and progesterone receptor (PR) and the clinico-pathologic features in endometrial carcinoma. METHODS: ER and PR contents of fresh tumor tissues taken from 70 cases of primary endometrial carcinoma were measured by biochemical (DCC) method and 30 paraffin-embedded archival specimens of the 70 cases also by immunohistochemical (IHC) method. RESULTS: Both ER and PR positive rates were 77.1% by DCC assay and 83.3% by IHC method. Excellent correspondency of one method to the other was observed (ER 83.3%, PR 86.7%). And the IHC method displayed further the origin of the tissue examined. The ER and PR levels correlated negatively with the grades of tumor (P < 0.01). ER and PR positive rates in adenocarcinoma (including papillary adenocarcinoma) and adenoacanthoma were higher than those in the other histological types (ER, P < 0.01; PR, P < 0.005). There was a positive correlation between the ER levels and obesity. CONCLUSIONS: The levels of ER and PR and the histopathological classification and grading of the tumor tissue reflect biologic behaviors of endometrial carcinoma. ER and PR assays are important for endocrinotherapy and in predicting prognosis.

Adenocarcinoma↗
PubMed1997

[The clinical and pathological characteristics of epithelial ovarian carcinoma in patients with age under 40].

OBJECTIVE: To investigate the clinical and pathological characteristics of epithelial ovarian carcinoma in patients with age under 40. METHODS: From Jan 1978 to Dec 1992, 54 cases with epithelial ovarian carcinoma under 40 years old were admitted to our hospital and enrolled in the study group, another 54 patients suffered from the same disease with age over 40 in the same period were served as control. Comparison analysis for clinical and pathologic data of 2 groups was performed using SPSS and SURVALC statistics software. RESULTS: Main complaint because of either pelvic mass or abdominal mass found by chance was more common in study group (46.3%) than that in control group (27.8%). whereas because of symptoms was less common in study group (53.7%) than in control group (72.2%). Other parameters such as early stage (I and II) rate (61.1%), unilateral tumor rate (68.5%), average maximum diameter of tumor (13.6 cm), highly differentiated rate (50%) and the possibility for tumor reductive surgery were higher in study group than in control group. The difference of histological pattern and chemotherapy between 2 groups was not significant. Single variate analysis showed that the prognosis was better in study group. The 2-year and 5-year survival rates were 69.8% and 50.2% respectively. No recurrence was found in the 8 patients in whom the contralateral healthy ovary remained. However multiple variate analysis indicated that age was not a prognostic factor. CONCLUSION: Epithelial ovarian carcinoma was prone to be lower degree malignancy in patients under 40 years therefore the prognosis of them was better. It might be resonable to have healthy ovary left in some select cases.

Adolescent↗
PubMed1997

Guillain-Barré syndrome: clinical analysis and pathological study on sural nerve biopsy of forty cases.

OBJECTIVE: To make clinical analysis and pathological study on 40-case Gullain-Barré syndrome with sural nerve biopsy. METHODS: A total of 90 cases of GBS were retrospectively analyzed of which sural nerve biopsies were performed in 40 cases. The type of GBS was determined according to Asbury and Ropper criteria, and its correlation with pathological findings was studied. RESULTS: In the 40 biopsy cases, demyelination was the predominant pathological change in 38 cases. Mild axonal degeneration was also seen in 13 of the 38 cases. Prominent axonal degeneration was seen in only 2 of 13 cases. The increased monocyte infiltration and varied capillary permeability were observed in 19 of 25 cases. Onion-bulb like changes were seen in 6 cases. CONCLUSION: We studied the correlation between paresthesia and the pathological findings of sural nerve biopsy and concluded that sural nerve biopsy is very useful in the diagnosis of GBS and its variant.

Adolescent↗
PubMed1997

Clinical, pathologic and genetic studies on mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes.

OBJECTIVE: To study the clinical, pathological and genetic characteristics of mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS). METHODS: Eight cases of MELAS (6 of them were from 2 families) underwent clinical study, muscle biopsy, autopsy on one patient, brain biopsy on one patient and genetic research. RESULTS: In clinical report the average age of onset was 10-22 years old. Four cases from one family were 3 brothers and their nephew (sister's son). The death age of the three brothers was 16-20 years. Two cases from another family were a brother and a sister. The six patients of the two families showed the typical inherited characters of MELAS. The symptoms were myoclonic epilepsy, stroke-like episodes, paralysis of limbs, progressive mental retardation and neurological deaf. CT showed calcification in globus pallidus and MRI demonstrated clearly the abnormal prolongation of T2-weighed signals that distributed in frontal, parietal, occipital and temporal cortex as multiple focal, cystic and laminar necrotic areas. Pathological studies on brain showed multi-focal, cystic, and laminar or spongy necrotic abnormality primarily in gray matter of frontal, parental, temporal and occipital cortex. Decrease and loss of nerve fibers of the sub-cortical white matters of the lesion areas of cortex and calcification of globus pallidus were also observed. Red ragged fibers (RRF) and abnormal mitochondron were found by muscle biopsies. A point mutation (A-G transition) at nt 4243 in the mitochondrial tRNA Leu (UUR) was confirmed by using PCR and Southern Blot. CONCLUSION: Although great progress has been made in the clinical, pathological and genetic research of MELAS, the pathogenesis of the disease remains further research.

Adolescent↗
PubMed1997

Genital Ureaplasma urealyticum infection in varicocele-related infertility.

OBJECTIVE: To assess the existence of a possible infectious factor in varicocele-related infertility. METHODS: A total of 925 seminal plasmas from 590 infertile men with varicocele and 335 infertile patients without palpable varicocele were cultured for Ureaplasma urealyticum infection, and routine semen analysis was made. RESULTS: The infection rate of Ureaplasma urealyticum in seminal plasmas was 48.22%. The asymptomatic genital infection of Ureaplasma urealyticum was traced in 329 (55.76%) varicocele men and 117 (34.93%) infertile patients without varicocele (control group). A significant quantitative difference in the incidence of genital Ureaplasma urealyticum infection between the varicocele and control group was observed (P < 0.005) and asthenozoospermia was significantly more prevalent in the patients with varicocele than in the other patients (P < 0.05). CONCLUSIONS: Genital Ureaplasma urealyticum infection may play a role in varicocele-related infertility. To prevent future infertility, men with both varicocele and genital Ureaplasma urealyticum infection may benefit from early evaluation and treatment.

Adult↗
PubMed1997

[Biologic effects of introduction of wild-type p53 cDNA into a human ovarian cancer cell line SKOV-3].

OBJECTIVE: To study the effects on biologic behavior in cells obtained from human ovarian cancer cell line SKOV-3 into which the wild-type p53 cDNA was introduced. METHOD: Recombinant eukaryotic expression vector pC53-SN3 containing full-length human wild-type p53 cDNA and vector containing neomycin resistance gene only were introduced by lipofectamine-mediated gene transfection into SKOV-3 cell line which does not express endogenous p53. The clones obtained were observed for their biologic behavior. RESULTS: (1) 2 clones named pC53 and 2 clones named pNeo were obtained after pC53-SN3 and vector transfection respectively; (2) The morphology of cells either from pC53 or from pNeo did not change significantly with respect to their parental SKOV-3; (3) The growth rate of cells from pC53 was much slower than that from SKOV-3, while the cell growth curve of pNeo was similar to that of SKOV-3; (4) The number of colones formed in the soft-agar by pC53 was significantly less than that by SKOV-3 or by pNeo; (5) The percentage of phase G1/G0 of pC53 was much higher than that of SKOV-3 and pNeo. CONCLUSION: Wild-type p53 cDNA may be considered as one of the target genes for the gene therapy of ovarian cancer.

Cell Cycle↗
PubMed1997

[LH-CG receptor protein expression in epithelial ovarian cancer].

OBJECTIVE: To evaluate the relationship between (LH-CG) receptor expression and prognosis in epithelial ovarian cancer. METHODS: The relative quantity of LH-CG receptor protein of epithelial ovarian cancer tissuse was detected with semiquantitative western immunobloting in 40 cases. The LH-CG receptor protein was located with immunohistochemistry. The LH-CG receptor was termed high expression if its concentration was more than and/or equal to the median, and low expression if its concentration was less than the median. 36 of the 40 cases were followed up at various intervals, the longest follow up period was 56 months. There were 16 cases with high LH-CG expression and 20 cases with low LH-CG receptor expression in which 9 cases died. RESULTS: The positive rate of LH-CG receptor protein expression was 72.5% (29/40). The level of LH-CG receptor protein expression in patients with stages I and II was higher than that in patients with stages III and IV, but it is not significant (P > 0.05). The LH-CG receptor concentration in the well-differentiated cancer group was twice as much as that in the poorly-differentiated cancer group. The difference between the well-differentiated group and the poorly-differentiated group was significant (P < 0.05). The 1-year and 3-year survival rates were 83.94% and 67.15% respectively in the high LH-CG receptor expression group. Both of the 1-year and 3-year survival rates were 33. 34% in the low LH-CG receptor expression group. The survival rates of the high expression group was significantly higher than those of the low expression group (P < 0.05). LH-CG receptor expression did not correlate with age, lymph node metastases, the size of residual tumor and CA125. CONCLUSION: The prognosis of patients with high LH-CG receptor expression is better than that of those with low expression.

Adult↗
PubMed1997

[Studies on epidemic hemorrhagic fever among rats in Jianghan Plian, Hubei Province, China].

Capture of rats by digging their cavities, identification of rat strains, sex and age, examination of their skin cut or damage, and detection of antigen and antibody of epidemic hemorrhagic fever virus (EHFV) were conducted in epidemic areas of epidemic hemorrhagic fever (EHF) in Jinaghan Plain, Hubei Province, to study prevalence of EHFV infection in rats. Results showed that Apodemus agarius and Rattus norvegius accounted for 69.7% and 23.6% of the total rats captured, respectively, their infection rates of EHFV were 21.8% and 30.9%, respectively. Infection rate of EHFV was significantly higher in adult rats than in sub-adult and young ones, with prevalence of 40.8%, 17.0% and 12.4%, respectively. Infection rate of EHFV was 45.9% in rats with skin cut, significantly higher than in those without it (13.9%). There was an obvious litter-clustering phenomenon in infected rats, but their litters distributed in space randomly. Serotyping of infected rats showed that Apodemus agarius mainly was in a wild rat pattern, Rattus norvegius in a domestic rat pattern, and a small number of rats were in undefined patterns. It indicated that Jinaghan Plain was a mixed epidemic area of EHF with domestic and wild rat patterns and with Apodemus agarius and Rattus norvegius as main reservoir host, and age, skin cut, and close contact with them were important factors contributing to transmit it.

Animals↗
PubMed1997

Loss of the cyclin-dependent kinase inhibitor p27(Kip1) protein in human prostate cancer correlates with tumor grade.

Loss of expression or mutational deletion of the cyclin-dependent kinase inhibitor p27(Kip1) has recently been implicated in malignant development. In this study, we investigated the relationship between p27(Kip1) protein expression and tumor grade in human prostate cancer by conducting an immunohistochemical analysis in a series of normal prostate, benign prostatic hyperplasia, and malignant prostate cancer specimens. The proliferative activity of prostatic tumors was determined on the basis of the Ki-67 nuclear antigen staining. A uniformly intense immunoreactivity for p27(Kip1) was localized to the nuclei of glandular epithelial cells of normal prostates. The benign glandular epithelia exhibited moderate immunostaining. In the malignant prostate tissue, however, a heterogeneous pattern of substantially reduced p27(Kip1) immunoreactivity was found among the glandular epithelial cells. The majority of primary prostate cancer specimens (68%) were totally negative for p27(Kip1) immunoreactivity, whereas the rest exhibited a significantly decreased p27(Kip1) expression, compared with the normal prostate (P < 0.01). Moreover, there was progressively diminished p27(Kip1) immunostaining with increased tumor grade. This loss of p27(Kip1) was associated with an increase in the proliferative index of prostatic tumors (r = 0.88). There was no significant relationship between p27(Kip) loss and the transforming growth factor beta receptor status of prostatic adenocarcinomas. These results indicate that frequent loss of the cyclin-dependent kinase inhibitor p27(Kip1) in human prostate cancer cells correlates with advancing histological aggressiveness, implicating deregulation of p27(Kip1) in prostate tumor progression.

Adenocarcinoma↗
PubMed1997

[A four-box multi-function testing system of pharmacology reaction].

The organism position matrix method, a new method of testing pharmacology reaction is proposed. On the basis of the method, we have developed a four-box multi-function testing system which can test the spontaneous activity, analgesic effect, and learning and memory ability of 1 to 4 mice in three dimensions respectively. Four quantitative parameters, the total distance, the movement intensity, the vertical number and the jumping number are put forward to describe the spontaneous activity. The starting time of continuous jumping and the jumping number are used to describe the analgesic effect. The time from the electrical shock to escape onto a safety platform and the number of the electrical shock are used to describe the learning and memory ability. The system has the characteristics of good repeatability, high efficiency, quantitative and automatic control.

Animals↗
PubMed1997

[Experimental study on prevention and treatment of neuroma by implanting nerve stump into muscle].

Prevention and treatment of traumatic neuroma by implanting the proximal neural stump into the muscle were studied. Sixteen SD rats were used for the experimental study. The proximal stump of the left sciatic nerve was implanted into the nearby muscle as the experiment side, whereas the proximal stump of the right sciatic nerve was left untreated as the control side. The results were assessed with histological and electrophysiological methods. The experiment demonstrated that neuroma was formed in the control side one month postoperatively, whereas in the experimental side the nerve fibers were dispersed among the muscle fibers and no definite neuroma was formed. Implantation of neural stump into muscle could prevent and treat traumatic neuroma.

Animals↗