Hepatitis B is a major health concern in the Asia-Pacific region,and is endemic in China,Southeast Asia,and Africa.Chronic hepatitis B virus(HBV)infection may cause hepatic cirrhosis and liver cancer.It is estimated t...Hepatitis B is a major health concern in the Asia-Pacific region,and is endemic in China,Southeast Asia,and Africa.Chronic hepatitis B virus(HBV)infection may cause hepatic cirrhosis and liver cancer.It is estimated that there are more than 350 million chronic HBV carriers worldwide,of whom approximately one quarter will die of chronic hepatitis B-related liver diseases.HBV is transmitted horizontally through blood and blood products or by sexual transmission,and vertically from mother to infant.Perinatal infection is the predominant mode of transmission in countries with a high prevalence of hepatitis B surface antigen(HBsAg)carriage,and perinatal transmission leads to high rates of chronic infection.Therefore,it is important to prevent the mother-to-child transmission(MTCT)of HBV.Research has shown that pregnant women with high HBV DNA levels have an increased risk of MTCT.However,most of the obstetrics guidelines do not make a distinction between pregnant women with high HBV DNA levels and those who are HBsAg positive only.This review addresses the management of pregnant women with high levels of HBV viremia,in terms of antiviral therapy,use of hepatitis B immunoglobulin(HBIG),the combined application of hepatitis B vaccine and HBIG,choice of delivery mode and feeding practices.展开更多
Background: The aim of this study was to assess the performance of apparent diffusion coefficient (ADC) measurement obtained with diffusion-weighted magnetic resonance imaging (DW-MRI) to distinguish renal cell c...Background: The aim of this study was to assess the performance of apparent diffusion coefficient (ADC) measurement obtained with diffusion-weighted magnetic resonance imaging (DW-MRI) to distinguish renal cell carcinomas (RCCs) from small benign solid renal tumors (〈4 cm). Methods: In this cross-sectional study, 49 consecutive patients with histopathologically confirmed small solid renal tumors, and seven healthy volunteers were imaged using nonenhanced MRI and DW-MRI. The ADC map was calculated using the b values of 0, 50, 400, and 600 s/ mm2 and values compared via the Kruskal-Wallis and Mann-Whitney tests. The utility of ADC for differentiating RCCs and benign lesions was assessed using a receiver operating characteristic curve. Multiple nonenhanced MRI features were analyzed by Logistic regression. Results: The tumors consisted of 33 cases of clear-cell RCCs (ccRCCs) and 16 cases of benign tumors, including 14 cases of minimal fat angiomyolipomas and 2 cases ofoncocytomas. The ADCs showed significant differences among benign tumors ([0.90 ±0.52] x 10 x mm2/s), ccRCCs ([1.53 ± 0.31 ] x 10 ^3 mm2/s) and the normal renal parenchyma ([2.22 ± 0.12]x 10^-3 mmVs) (P 〈 0.001). Moreover, there was statistically significant difference between high and low-grade ccRCCs (P = 0.004). Using a cut-offADC of 1.36± 10 3 mm2/s, DW-MRI resulted in an area under the curve (AUC), sensitivity, and specificity equal to 0.839, 75.8%, and 87.5%, respectively. Nonenhanced MRI alone and the combination of imaging methods led to an AUC, sensitivity and specificity equal to 0.919, 93.9%, and 81.2%, 0.998, 97%, and 100%, respectively. The Logistic regression showed that the location of the center of the tumor (inside the contour of the kidney) and appearance of stiffblood vessel were significantly helpful for diagnosing ccRCCs. Conclusions: DW-MRI has potential in distinguishing ccRCCs from benign lesions in human small solid renal tumors (〈4 cm), and in increasing the accuracy for diagnosing ccRCCs when combined with nonenhanced MRI.展开更多
文摘Hepatitis B is a major health concern in the Asia-Pacific region,and is endemic in China,Southeast Asia,and Africa.Chronic hepatitis B virus(HBV)infection may cause hepatic cirrhosis and liver cancer.It is estimated that there are more than 350 million chronic HBV carriers worldwide,of whom approximately one quarter will die of chronic hepatitis B-related liver diseases.HBV is transmitted horizontally through blood and blood products or by sexual transmission,and vertically from mother to infant.Perinatal infection is the predominant mode of transmission in countries with a high prevalence of hepatitis B surface antigen(HBsAg)carriage,and perinatal transmission leads to high rates of chronic infection.Therefore,it is important to prevent the mother-to-child transmission(MTCT)of HBV.Research has shown that pregnant women with high HBV DNA levels have an increased risk of MTCT.However,most of the obstetrics guidelines do not make a distinction between pregnant women with high HBV DNA levels and those who are HBsAg positive only.This review addresses the management of pregnant women with high levels of HBV viremia,in terms of antiviral therapy,use of hepatitis B immunoglobulin(HBIG),the combined application of hepatitis B vaccine and HBIG,choice of delivery mode and feeding practices.
文摘Background: The aim of this study was to assess the performance of apparent diffusion coefficient (ADC) measurement obtained with diffusion-weighted magnetic resonance imaging (DW-MRI) to distinguish renal cell carcinomas (RCCs) from small benign solid renal tumors (〈4 cm). Methods: In this cross-sectional study, 49 consecutive patients with histopathologically confirmed small solid renal tumors, and seven healthy volunteers were imaged using nonenhanced MRI and DW-MRI. The ADC map was calculated using the b values of 0, 50, 400, and 600 s/ mm2 and values compared via the Kruskal-Wallis and Mann-Whitney tests. The utility of ADC for differentiating RCCs and benign lesions was assessed using a receiver operating characteristic curve. Multiple nonenhanced MRI features were analyzed by Logistic regression. Results: The tumors consisted of 33 cases of clear-cell RCCs (ccRCCs) and 16 cases of benign tumors, including 14 cases of minimal fat angiomyolipomas and 2 cases ofoncocytomas. The ADCs showed significant differences among benign tumors ([0.90 ±0.52] x 10 x mm2/s), ccRCCs ([1.53 ± 0.31 ] x 10 ^3 mm2/s) and the normal renal parenchyma ([2.22 ± 0.12]x 10^-3 mmVs) (P 〈 0.001). Moreover, there was statistically significant difference between high and low-grade ccRCCs (P = 0.004). Using a cut-offADC of 1.36± 10 3 mm2/s, DW-MRI resulted in an area under the curve (AUC), sensitivity, and specificity equal to 0.839, 75.8%, and 87.5%, respectively. Nonenhanced MRI alone and the combination of imaging methods led to an AUC, sensitivity and specificity equal to 0.919, 93.9%, and 81.2%, 0.998, 97%, and 100%, respectively. The Logistic regression showed that the location of the center of the tumor (inside the contour of the kidney) and appearance of stiffblood vessel were significantly helpful for diagnosing ccRCCs. Conclusions: DW-MRI has potential in distinguishing ccRCCs from benign lesions in human small solid renal tumors (〈4 cm), and in increasing the accuracy for diagnosing ccRCCs when combined with nonenhanced MRI.