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61.
Nipah viruses from pigs from a Malaysian 1998 outbreak were isolated and sequenced. At least two different Nipah virus strains, including a previously unreported strain, were identified. The findings highlight the possibility that the Malaysia outbreaks had two origins of Nipah virus infections.  相似文献   
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BACKGROUND: Estrogen and progesterone immunoregulate the genital environment by expression of cytokines and growth factors. OBJECTIVE: To investigate the pattern of expression of T-helper cytokines during the ovarian cycle compared with women with chronic anovulation resistant to clomiphene citrate. HYPOTHESIS: Expression of T-helper cytokines in women with chronic anovulation may be different from the pattern in women with a normal ovarian cycle. METHODS: We evaluated 31 infertile women having laparoscopy for evaluation of tubal patency and evidence of ovulation in two groups during (a) the luteal phase (17 women) and (b) the follicular phase (14 women). A third group was composed of 14 women with polycystic ovarian syndrome, but they were resistant to clomiphene citrate for induction of ovulation and had laparoscopic ovarian cautery. Peritoneal fluid was collected during laparoscopy. Estimation of T-helper cytokine interleukin (IL)-2, tumor necrosis factor (TNF)-alpha, IL-4 and IL-6 in serum, peritoneal fluid and culture of the peritoneal mononuclear cells was performed by ELISA. Serum luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin, estradiol and progesterone were evaluated by the Vidas Parametric System. RESULTS: The LH : FSH ratio was significantly higher in the women with polycystic ovaries than in the ovulatory groups. IL-2 and IFN-gamma were more highly expressed in the follicular phase but the T-helper 2 cytokines IL-4 and IL-6 predominated in the luteal phase, serum, peritoneal fluid and culture of the peritoneal mononuclear cells. From the follicular to the mid-luteal phase, IL-6 increased three to fivefold in the serum and peritoneal fluid, but there was low expression with anovulation. CONCLUSIONS: The peritoneal fluid levels of IL-4 and IL-6 are higher in the luteal phase. Low IL-6 levels in chronic anovulation may be a marker of resistance to clomiphene citrate.  相似文献   
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OBJECTIVE: Treatment and management of congenital as well as post-traumatic trachea stenosis remains a challenge in pediatric surgery. The aim of this study was to reconstruct a trachea with human nasal septum chondrocytes by using the combination of biodegradable hydrogel and non-biodegradable high-density polyethylene (HDP) as the internal predetermined shape scaffold. METHODS: Human nasal septum cartilage was harvested as excessive tissue after elective septoplasty and digested in 0.6% collagenase II. Chondrocytes were cultured in an equal volume mix of Ham's F12 medium and Dulbecco's modified eagle medium added with 10% fetal bovine serum and basic fibroblast growth factor. After two passages, the cultured chondrocytes were trypsinized and mixed with biodegradable hydrogel Pluronic F127. The chondrocytes-hydrogel admixture was then painted over the HDP as the internal support in a predetermined trachea shape. The composite was then implanted subcutaneously in athymic mice. RESULTS: After 8 weeks of in vivo implantation, the tissue engineered trachea constructs were harvested. Macroscopic appearance of the tissue engineered trachea constructs demonstrated that the HDP were 80-90% covered with yellowish glistering cartilage like tissue without any sign of inflammation. The tissue engineered trachea cartilage consisted of evenly spaced lacunae embedded in basophilic matrix and stained red with Safranin-O staining denoting abundant proteoglycans production. Type II collagen gene which was expressed in native cartilage was highly expressed in this tissue engineered trachea cartilage. CONCLUSION: We have successfully reconstructed a trachea in vivo with human nasal septum chondrocytes using HDP as the internal support. This construct has the advantage of bio-inert and strength in which both are important properties in tracheal reconstruction.  相似文献   
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The majority of global incidences of oral cancer occur in Asia, and the aetiology of oral cancer is different in Asia as it is in the West. However, whereas there is a growing understanding of the molecular mechanisms of oral cancer progression in the West, there is little progress in this understanding in Asia. In particular, the role of the p53 pathway in modulating cancer progression in Asian oral cancer remains unclear. In this study, we micro-dissected and analysed 20 well-differentiated oral squamous cell carcinoma specimens for alterations in the p53 pathway. We found that 6/20 samples contained mutations in the p53 gene which occurred in three hotspots, at codon 203, 218 and 296. Furthermore, 6/20 samples had a homozygous deletion of p14ARF, but notably p14ARF deletion and p53 mutation events were often independent and mutually exclusive. Strikingly, MDM2 was upregulated in 20/20 samples, but not in 3/3 normal tissue specimens. Taken together, these data suggest that inactivation of the p53 pathway is a frequent event in oral squamous cell carcinoma, which occurs by an aberration in one of a number of players in the p53 pathway.  相似文献   
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Noruddin NA  Saim AB  Chua KH  Idrus R 《The Laryngoscope》2007,117(12):2139-2145
OBJECTIVE: To compare a co-culture system with a conventional dispase-dissociation method for obtaining functional human respiratory epithelial cells from the nasal turbinates for tissue engineering application. METHODS: Human respiratory epithelial cells were serially passaged using a co-culture system and a conventional dispase-dissociation technique. The growth kinetics and gene expression levels of the cultured respiratory epithelial cells were compared. Four genes were investigated, namely cytokeratin-18, a marker for ciliated and secretory epithelial cells; cytokeratin-14, a marker for basal epithelial cells; MKI67, a proliferation marker; and MUC5B, a marker for mucin secretion. Immunocytochemical analysis was performed using monoclonal antibodies against the high molecular-weight cytokeratin 34 beta E12, cytokeratin 18, and MUC5A to investigate the protein expression from cultured respiratory epithelial cells. RESULTS: Respiratory epithelial cells cultured using both methods maintained polygonal morphology throughout the passages. At passage 1, co-cultured respiratory epithelial showed a 2.6-times higher growth rate compared to conventional dispase dissociation technique, and 7.8 times higher at passage 2. Better basal gene expression was observed by co-cultured respiratory epithelial cells compared to dispase dissociated cells. Immunocytochemical analyses were positive for the respiratory epithelial cells cultured using both techniques. CONCLUSION: Co-culture system produced superior quality of cultured human respiratory epithelial cells from the nasal turbinates as compared to dispase dissociation technique.  相似文献   
69.
OBJECTIVE: Maxillofacial trauma in children is not common worldwide. Domestic injuries are frequently seen in younger children while older children are mostly involved in motor vehicle accidents (MVA). The objective of this study was to analyze the pattern of maxillofacial injuries in pediatric patients referred to three government main hospitals in different areas of West Malaysia. METHODS: Patients' records of three selected hospitals in Malaysia (National University of Malaysia Hospital, Kajang Hospital and Seremban Hospital) from January 1999 to December 2001 were reviewed. Data associated with demographics, etiology of injury in relation to age group, type of injuries whether soft tissues of hard tissue in relation to age group and treatment modalities were collected. RESULTS: A total of 521 pediatric patients' records were reviewed. Malays made up the majority of patients with maxillofacial injuries in the three hospitals. Males outnumbered females in all the three hospitals. Injuries commonly occur in the 11-16 years old. MVA was the most common etiology followed by fall and assault. Soft tissue injuries were the most common type of injuries in all the hospitals. In relation to fractures, mandible was the most common bone to fracture with condyle being the most common site. Orbital fracture was the most common fracture in the midfacial area. Most of the fractures were managed conservatively especially in the younger age groups. Open reduction with or without internal fixation was more frequently carried out in the 11-16 years old group. CONCLUSION: Children exhibit different pattern of clinical features depending on the etiology and stage of their bone maturation. A dedicated team, who is competent in trauma and aware of the unique anatomy, physical and psychological characteristics of children, should manage pediatric patient with trauma.  相似文献   
70.
BACKGROUND: The honeymoon period (i.e., partial remission) of type 1 diabetes mellitus is characterized by reduced insulin requirements while good glycemic control is maintained. The clinical significance is the potential possibility for pharmacological intervention during this period to either slow down or arrest the ongoing destruction of the remaining beta-cells. METHODS: A group of 103 diabetic children, younger than 12 yr of age, were prospectively studied to assess the frequency, duration, and factors that may affect partial remission. At the time of admission, patients were characterized by age, gender, symptom duration, diabetic ketoacidosis (DKA), and blood sugar level at admission. The honeymoon period was defined as a period with insulin requirements of less than 0.5 U/kg/day and hemoglobin A1c (HbA1c) level of less or equal to 6%. RESULTS: Partial remission occurred in 71, being complete in three. The length of time until remission was 28.6 +/- 12.3 (mean +/- SD) days. The duration of remission was 7.2 +/- 4.8 months. Remission rates were higher in those patients older than 5 yr compared with those between 3 and 5 yr of age. DKA at presentation and long duration of symptoms were associated with lower duration of remission (p < 0.001 and p < 0.001, respectively). Children in whom remission occurred had significantly lower blood glucose levels and higher pH at presentation (p < 0.001 and p < 0.001, respectively). CONCLUSIONS: Young age and severe disease at presentation are associated with decreased residual beta-cells function that is reflected by a lower incidence of partial remission. These observations are important to consider in the research regarding therapies that will have the potential goal to induce prolonged and/or complete remission at disease onset or shortly thereafter.  相似文献   
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