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71.
72.
An influenza B outbreak occurred in Taiwan in 2004 and 2005, during which both Victoria (Vic) and Yamagata (Ya) lineages cocirculated. This study examined 36 influenza B viral genomes isolated during the outbreak to reveal their reassortment patterns. According to the isolate groupings in phylogenetic analysis, we were able to categorize those 36 isolates as being of either the Victoria or Yamagata lineage for all eight influenza B virus genomic segments, except for the NS gene, in which clades A and B existed. Based on these groupings, three genome patterns clearly emerged, namely, pattern I (Vic+Vic+Ya+Vic+Ya+Ya+Ya+A, from segments 1 to 8), pattern II (Ya+Ya+Ya+Ya+Ya+Ya+Ya+B), and pattern III (Ya+Ya+Ya+Ya+Ya+Ya+Ya+A). According to the timeline of those isolates under investigation, it appears that pattern I and II viruses could have generated pattern III via reassortment of the NS gene. On the other hand, a genomewide comparison of all six pattern III Taiwanese viruses with 37 international influenza B viral genomes showed that two international strains, B/Oslo/71/04 and B/England/23/04, were consistently clustered with the pattern III viruses isolated in Taiwan in 2004 and 2005, suggesting that Taiwanese pattern III viruses might also have been imported due to their matching genomic composition.  相似文献   
73.
Zheng Z  Pan J  Chu B  Wong YC  Cheung AL  Tsao SW 《Human pathology》1999,30(4):458-466
Nasopharyngeal carcinoma (NPC) is predominantly of the undifferentiated histological subtype. Histological differentiation is of limited prognostic significance in NPC. Recent studies have suggested that downregulation of the cadherin-catenin cell adhesion complex may play a crucial role in the initial stage of cancer invasion and metastasis and is associated with poor prognosis in human cancers. Expression of E-cadherin has not been reported previously in NPC, and its prognostic value in NPC is unknown. The purpose of this study was to examine the expression pattern of E-cadherin and its associated partner, beta-catenin, in NPC and their possible applications as prognostic markers to predict the clinical outcome of NPC. Expression of the E-cadherin and beta-catenin was examined by immunohistochemical methods in 74 cases of primary NPC and 17 of their corresponding lymph node metastases. Normal nasopharyngeal epithelium showed strong and homogeneous immunocytochemical staining of E-cadherin and beta-catenin at the cell membranes and intercellular junctions. In contrast, primary NPC showed variable and heterogeneous staining patterns of E-cadherin and beta-catenin. Loss of membranous E-cadherin expression was significantly associated with advanced stages of diseases (P<.001). Eighty percent to ninety percent of NPC in stages IV and V (Ho's staging), respectively, showed a reduced (<35%) membranous staining of E-cadherin compared with normal nasopharyngeal epithelium. Expression of beta-catenin also was downregulated in advanced NPC. Ninety percent to one hundred percent of NPC in stages IV and V (Ho's staging) expressed a reduction (<35%) of imnmunocytochemical staining of beta-catenin. The expression pattern of beta-catenin staining was strongly associated with the expression of E-cadherin (P<.001). Unlike E-cadherin, nuclear staining of beta-catenin expression was observed in some of the primary NPC and lymph node metastasis. Reduced expression of E-cadherin and beta-catenin expression was associated with a shorter survival of NPC patients (P<.001). In advanced NPC patients (stages IV and V), a significant difference in survival was observed in tumors with higher or lower levels of E-cadherin expression (P=.0224, log-rank test). These observations suggests that expression of E-cadherin and beta-catenin may have prognostic values in NPC patients.  相似文献   
74.
Telomerase activity in gestational trophoblastic disease   总被引:12,自引:0,他引:12       下载免费PDF全文
AIMS: To investigate the pattern of telomerase activity in hydatidiform mole as compared with normal placenta and choriocarcinoma, and to determine the prognostic significance of telomerase activity in hydatidiform mole. METHODS: Telomerase activity in 35 cases of hydatidiform mole, 35 normal placentas, one choriocarcinoma sample, and two choriocarcinoma cell lines (JAR, JEG3) was determined using the sensitive polymerase chain reaction based telomeric repeat amplification protocol (TRAP) assay. Two cases of breast carcinoma and two cases of ovarian carcinoma were also included as positive controls in the telomerase assay. RESULTS: Telomerase activity was detected in 11 of 30 early placentas (36.7%), one of five term placentas (20%), five of 27 hydatidiform moles which regressed spontaneously (18.5%), and six of eight hydatidiform moles which developed persistent trophoblastic disease (75%) (including three which developed metastases). Hydatidiform moles which subsequently developed persistent disease, especially those which metastasised, were more likely to express telomerase activity (p < 0.01). However, there was no significant difference in the frequency of telomerase activity between early placentas and hydatidiform mole. Strong telomerase activity was observed in choriocarcinoma tissue, choriocarcinoma cell lines, and ovarian and breast carcinomas. CONCLUSIONS: Telomerase activation occurs in hydatidiform mole with a similar incidence to early normal placentas. This supports the concept that hydatidiform mole is essentially an abnormal conceptus. There is an association between telomerase activation and the development of persistent trophoblastic disease. Further study is warrant to confirm the prognostic significance of telomerase activity in hydatidiform mole.  相似文献   
75.
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77.
Despite advances in the surgical treatment and medical management over the last 20 years, neonates with congenital diaphragmatic hernia (CDH) remain one of the most challenging patient groups for all clinicians. Treatment strategies have shifted from emergent surgical repair and maximum ventilatory support to delayed repair and preoperative hemodynamic stabilization with lung-sparing ventilation strategies and extracorporeal membrane oxygenation. Subsequently, overall survival has improved to as high as 80% in some centers. However, specific treatment criteria are vague and highly variable amongst centers. This lack of consensus of these treatment modalities remains elusive due to the heterogeneity in disease severity as well as heterogeneity in patient care amongst centers. As a result of the rare incidence of disease and limited experience of individual centers, the evidence for CDH is typically reported as a homogenous disease largely supported by case series and networked-based studies. To better evaluate the data and compare treatment strategies, a classification and stratification of disease and centers is needed.  相似文献   
78.

Purpose

Shunt procedures used to treat cryptococcal meningitis complicated with hydrocephalus and/or increased intracranial pressure (IICP) could result in cerebrospinal fluid (CSF) overdrainage, thereby presenting therapeutic challenges.

Methods

We analyzed the clinical features and neuroimaging findings after the ventriculoperitoneal (VP) shunt procedure in 51 HIV (Human Immunodeficiency Virus)-negative patients with cryptococcal meningitis, to assess the risk factors associated with post-shunt CSF overdrainage.

Results

Symptomatic CSF overdrainage occurred in 12% (6/51) of patients with cryptococcal meningitis who underwent the shunt procedure. Rapid deterioration of neurological conditions was found in 6 patients after the shunt procedure was performed, including disturbed consciousness, quadriparesis, and dysphasia in 5 patients and severe ataxia in 1. The mean duration of CSF overdrainage after the shunting procedure was 2–7 days (mean 4 days). The mean interval between meningitis onset to shunting procedure remained independently associated with CSF overdrainage, and the cut-off value for predicting CSF overdrainage in interval between meningitis onset to shunting procedure was 67.5 days.

Conclusions

CSF overdrainage after the VP shunt procedure is not rare, especially in patients with a high-risk of cryptococcal meningitis who also have a prolonged duration of hydrocephalus and/or IICP.  相似文献   
79.

Background/purpose

The incidence of carbapenem-resistant Pseudomonas aeruginosa (CRPA) related healthcare-associated infection (HAI) has increased in recent year worldwide. This study is to investigate the risk factors associated with CRPA infections in a university hospital setting in Taiwan to provide more information for clinician and infection control system.

Methods

A retrospective cross-sectional study was conducted from January 1st, 2009 to June 30th, 2014. Patients with P. aeruginosa related HAI were included and divided into the CRPA case group and carbapenem-susceptible Pseudomonas aeruginosa (CSPA) control group. The medical records were reviewed to identify risk factors for CRPA HAI and mortality. Patients with prior use of any anti-pseudomonal carbapenems were included in subgroup analysis.

Results

395 cases of P. aeruginosa infection were enrolled from total of 3263 HAI events; 63 were CRPA and 332 were CSPA. The prevalence of CRPA was 15.9% (63/395). Significant risk factors related to CRPA infection were longer time at risk, prior use of anti-pseudomonal carbapenems, and prior use of aminoglycoside (p < 0.05, 0.01, and 0.05). Furthermore, anti-pseudomonal carbapenem monotherapy did not significantly increase risk for CRPA infection.

Conclusion

The worldwide CRPA prevalence has been on the raise and Taiwan has been also keeping up with the trend. Antimicrobials usage should be monitored carefully, especially with carbapenems and aminoglycoside. Clinicians should be award of and understand about the risk of CRPA infection, which increases by 1% with each hospitalization day.  相似文献   
80.
BACKGROUND: Viruses are a frequent cause of upper respiratory tract infections in children. Like Taiwan, there were few virological surveillance systems for respiratory viral infections among children in developing countries. MATERIALS AND METHODS: During August 1995 and July 1997, 6-10 throat swab specimens per week were taken from pediatric outpatients with acute, febrile upper respiratory tract infections (URTI). The specimens were randomly obtained by two pediatricians at Chang Gung Children's Hospital and sent for virus isolation and identification. RESULTS: A total of 910 specimens were collected and 365 specimens (40%) were positive for at least 1 virus and included 81 enterovirus, 73 adenovirus, 58 influenza B virus, 54 influenza A virus, 48 cytomegalovirus (CMV), 25 herpes simplex virus-1 (HSV-1), 7 parainfluenza virus, 3 respiratory syncytial virus (RSV) and 16 mixed viruses. Adenovirus and enterovirus were identified throughout the study period. No seasonal variation was noted for adenovirus while enterovirus peaked between May and July and also during September and November. Influenza viruses, both A and B, were identified during two periods, respectively and altogether, influenza viruses could be detected almost throughout the year. An association between the virus type identified and the mean age of patients was found (P-value = 0.0001 by ANOVA test). The mean age of patients infected with influenza viruses, either A or B, was significantly higher than those of patients infected with adenovirus, HSV-1, CMV and enterovirus. CONCLUSION: The results of this study demonstrate that adenovirus and enterovirus are the two most common viruses isolated from pediatric outpatients with acute, febrile URTIs and can be identified throughout the year in northern Taiwan. Influenza viruses also can be identified throughout the year and during the epidemic, a child older than 5 years of age with acute febrile URTI is likely to be a case of influenza.  相似文献   
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