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81.
Incidence of human papillomavirus (HPV) attributable oropharyngeal cancers (OPCs) has been increasing globally, especially among men in high-income countries. There is a lack of studies comparing oral HPV prevalence by age and country among healthy men. The purpose of our study was to assess oral HPV prevalence by country and age. Participants of the HPV Infection in Men Study (HIM), a cohort of 3,098 healthy men from São Paulo, Brazil, Cuernavaca, Mexico and Tampa, USA, were studied. Oral HPV prevalence and type distribution were assessed using the SPF10 PCR-DEIA-LiPA25 system. The prevalence of any HPV in Brazil, Mexico and the US was 8.7% (95% CI: 7.1%, 10.4%), 10.0% (95% CI: 8.3%, 12.1%) and 7.6% (95% CI: 5.9%, 9.5%), respectively, while the prevalence of high-risk HPV was 5.3% (95% CI: 4.1%, 6.7%), 7.3% (95% CI: 5.7%, 9.0%) and 5.4% (95% CI: 4.0%, 7.0%), respectively. No significant differences in prevalence of grouped HPV types were observed by country despite significant differences in sexual behaviors. However, the age-specific prevalence of oral HPV differed by country. Brazilian (6.0% [95% CI: 3.4%, 9.7%]) and Mexican (9.2% [95% CI: 5.6%, 14.0%]) participants had peak high-risk HPV prevalence among men aged 41–50 years whereas the US participants had peak prevalence at ages 31–40 years (11.0% [95% CI: 6.4%, 17.3%]). In conclusion, oral HPV prevalence was low with no difference in overall prevalence observed by country. Factors associated with the differences in oral HPV age-patterning by country and sexual orientation require further study.  相似文献   
82.
Dose-dense adjuvant chemotherapy is standard of care in high-risk early breast cancer patients. However, its role in HER2-positive patients is still uncertain. In this exploratory analysis of the GIM2 trial, we investigated the efficacy of dose-dense chemotherapy in HER2-positive breast cancer patients with or without exposure to trastuzumab. In the GIM2 trial, node-positive early breast cancer patients were randomized to receive four cycles of (fluorouracil)epirubicin/cyclophosphamide followed by four cycles of paclitaxel administered every 2 (dose-dense) or 3 (standard-interval) weeks. After approval of adjuvant trastuzumab, protocol was amended in April 2006 to allow use of trastuzumab for 1 year after chemotherapy completion in HER2-positive patients. The efficacy of dose-dense chemotherapy in terms of disease-free survival (DFS) and overall survival (OS) was assessed according to HER2 status and trastuzumab use. Out of 2,003 breast cancer patients, HER2 status was negative/unknown in 1,551 patients; among the 452 patients with HER2-positive breast cancer, chemotherapy alone or followed by trastuzumab was given to 320 and 132 patients, respectively. Median follow-up was 8.1 years. No significant interaction between HER2 status, trastuzumab use and chemotherapy treatment was observed for both DFS (p = 0.698) and OS (p = 0.708). Nevertheless, there was no apparent benefit in the HER2-positive group treated with trastuzumab (DFS: HR, 0.99; 95% CI 0.52–1.89; OS: HR, 0.95; 95% CI 0.37–2.41). Although dose-dense chemotherapy was associated with a significant survival improvement in high-risk breast cancer patients, its benefit appeared to be smaller (if any) in patients with HER2-positive disease who received adjuvant trastuzumab.  相似文献   
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The Na+/taurocholate co-transporting polypeptide (NTCP, gene symbol SLC10A1) is both a physiological bile acid transporter and the high-affinity hepatic receptor for the hepatitis B and D viruses (HBV/HDV). Virus entry via endocytosis of the virus/NTCP complex involves co-factors, but this process is not fully understood. As part of the innate immunity, interferon-induced transmembrane proteins (IFITM) 1–3 have been characterized as virus entry-restricting factors for many viruses. The present study identified IFITM3 as a novel protein–protein interaction (PPI) partner of NTCP based on membrane yeast-two hybrid and co-immunoprecipitation experiments. Surprisingly, IFITM3 knockdown significantly reduced in vitro HBV infection rates of NTCP-expressing HuH7 cells and primary human hepatocytes (PHHs). In addition, HuH7-NTCP cells showed significantly lower HDV infection rates, whereas infection with influenza A virus was increased. HBV-derived myr-preS1 peptide binding to HuH7-NTCP cells was intact even under IFITM3 knockdown, suggesting that IFITM3-mediated HBV/HDV infection enhancement occurs in a step subsequent to the viral attachment to NTCP. In conclusion, IFITM3 was identified as a novel NTCP co-factor that significantly affects in vitro infection with HBV and HDV in NTCP-expressing hepatoma cells and PHHs. While there is clear evidence for a direct PPI between IFITM3 and NTCP, the specific mechanism by which this PPI facilitates the infection process remains to be identified in future studies.  相似文献   
85.
86.

Background

Hepatitis E virus (HEV) infection in patients with pre-existing liver disease has shown high morbidity and lethality. The consequences of HEV superinfection in patients with chronic hepatitis C virus (HCV) infection are not fully understood. This study aimed to evaluate the association between the presence of anti-HEV antibodies, liver cirrhosis, and insulin resistance.

Methods

A total of 618 patients chronically infected with HCV were included from three reference centers for viral hepatitis in São Paulo, Brazil. Presence of anti-HEV IgG was assessed by enzyme-linked immunosorbent assay (WANTAI HEV-IgG ELISA).

Results

The seroprevalence of anti-HEV in patients with cirrhosis was significantly higher than in patients without cirrhosis (13.2% vs 8%, OR = 1.74, p = 0.04). Seropositivity for anti-HEV, adjusted for sex, age, and HCV genotype showed an association trend with hepatic cirrhosis (aOR = 1.75, p = 0.059). Presence of HEV antibodies, adjusted for age, body mass index and cirrhosis, was shown to be independently associated with insulin resistance (aOR: 4.39; p = 0.045).

Conclusion

Patients with chronic hepatitis C are under risk of hepatitis E virus superinfection in Brazil. The trend toward association between cirrhosis and previous HEV infection suggests that it may accelerate liver fibrosis in patients with chronic hepatitis C. In addition, previous infection by HEV is independently associated with insulin resistance in the studied population, which may be an extra-hepatic manifestation of hepatitis E that persists after resolution of the active infection, and may contribute to fibrosis progression.  相似文献   
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88.
BACKGROUND: Controversy exists regarding axillary dissection (ALND) for sentinel node (SLN) metastases detected as isolated tumor cells (ITC). We hypothesized that the number of positive non-SLNs is low and ALND is unnecessary for most patients with ITC. METHODS: From 1995 to 1999, 634 breast cancer patients underwent SLND. SLNs were examined using immunohistochemistry if hematoxylin and eosin was negative. ALND was recommended for ITC-positive SLNs. RESULTS: Seventy-eight patients (12.3%) with ITC-positive SLNs were offered ALND. Sixty-one consented, whereas 17 refused. Fifty-eight (95.1%) had negative non-SLNs. Three (4.9%) had non-SLN metastases. One patient (1.6%) had macrometastatic disease, whereas 2 (3.3%) had micrometastases. No ITC-only-positive SLN patient experienced axillary recurrence. CONCLUSIONS: When ALND was performed for ITC, 1.6% of non-SLNs harbored macrometastases and 3.3% had micrometastases. When ALND was not performed, axillary recurrence was not seen. The low risk of non-SLN disease in this study fails to support the routine use of ALND for ITC-positive SLNs.  相似文献   
89.
Laparoscopic cholecystectomy in Child-Pugh class C cirrhotic patients.   总被引:3,自引:0,他引:3  
OBJECTIVES: This study aimed to determine whether laparoscopic cholecystectomy is a safe and advisable procedure in Child-Pugh C cirrhotic patients with symptomatic cholelithiasis. METHODS: The records of 42 laparoscopic cholecystectomies performed between January 1995 and February 2004 in patients with Child-Pugh A, B, and C cirrhosis were retrospectively reviewed, focusing on the 4 patients with Child-Pugh C cirrhosis. RESULTS: Among the 38 Child-Pugh A and B patients, no deaths occurred. In this group, only 1 Child-Pugh B cirrhotic patient required blood transfusion, and postoperative morbidity occurred in 10 patients including hemorrhage, wound infection, intraabdominal collection, and cardiopulmonary complications (morbidity rate 26%). The mean postoperative stay was 5 days (range, 3 to 13). The indication for surgery in the 4 Child-Pugh C patients was acute cholecystitis. In this group, 2 deaths occurred for severe liver failure in 1 case and for sepsis in the other. One patient developed heavy gallbladder bed bleeding, and a second operation was necessary to control the hemorrhage. The morbidity rate was 75%. Only 1 patient had no complications. The mean postoperative stay was 10 days (range, 4 to 17). CONCLUSIONS: Laparoscopic cholecystectomy is a safe procedure in well-selected Child-Pugh A and B cirrhotic patients indicated for surgery, but it is a very high-risk procedure in Child-Pugh C patients. Indications for surgery in Child-Pugh C patients should be evaluated very carefully and surgery should be avoided unless the patient needs an emergency cholecystectomy for acute cholecystitis. Child-Pugh C cirrhotic patients might better benefit from percutaneous drainage of the gallbladder.  相似文献   
90.
To confirm recent observations about the relationship between immunosuppression and the recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT), we retrospectively analyzed 70 consecutive HCC patients who underwent LT and received cyclosporine (CsA)-based immunosuppression. CsA trough blood levels, measured with the same technique (fluorescence polarization immunoassay), were analyzed at different time points after transplantation. The exposure to the drug was calculated with the trapezoidal rule in each patient. CsA was associated with steroids in 26 patients and steroids and azathioprine in 44 patients. HCC recurred in 7 patients (10.0%). Different immunosuppressive schedules (CsA and steroids vs. CsA, steroids, and azathioprine) or the cumulative dosage of steroids and azathioprine did not influence HCC recurrence that was associated instead with CsA exposure (278.3 +/- 86.4 ng/mL in recurrent vs. 169.9 +/- 33.3 in tumor-free patients; P < 0.001); CsA exposure above 189.6 ng/mL was related to HCC recurrence at the receiver operating characteristic analysis (ROC). The relationship between CsA exposure; various clinical (sex, age, viral- vs. non-viral-related cirrhosis, preoperative vs. incidental diagnosis of HCC, alpha-fetoprotein [AFP] blood level), pathologic (pathologic tumor staging [pT] stage, presence of Milan criteria), and histologic (grading, presence of microvascular tumor invasion) parameters; and tumor recurrence were assessed. AFP (P = 0.032), microvascular tumor invasion (P = 0.044), and CsA exposure (P < 0.001) influenced recurrence-free survival at the univariate analysis; CsA exposure was the only independent prognostic determinant at multivariate analysis (P < 0.001). High CsA exposure favors tumor recurrence; CsA blood levels should be kept to the effective minimum in HCC patients. In the presence of pathologic and histologic risk factors, specific immunosuppressive protocols should be considered.  相似文献   
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