On the glacial-interglacial variability of the Asian monsoon in speleothem δ18O records.

While Asian monsoon (AM) changes have been clearly captured in Chinese speleothem oxygen isotope (δ18O) records, the lack of glacial-interglacial variability in the records remains puzzling. Here, we report speleothem δ18O records from three locations along the trajectory of the Indian summer monsoon (ISM), a major branch of the AM, and characterize AM rainfall over the past 180,000 years. We have found that the records close to the monsoon moisture source show large glacial-interglacial variability, which then decreases landward. These changes likely reflect a stronger oxygen isotope fractionation associated with progressive rainout of AM moisture during glacial periods, possibly due to a larger temperature gradient and suppressed plant transpiration. We term this effect, which counteracts the forcing of glacial boundary conditions, the moisture transport pathway effect.

Magnetic Resonance Spectroscopy in Living-Donor Liver Transplantation.

OBJECTIVE: The purpose of this study is to evaluate the accuracy rate of the one breath-hold single voxel hydrogen-1 magnetic resonance spectroscopy (MRS) in comparison with intraoperative biopsy for liver fat quantification in living-donor liver transplantation. MATERIALS AND METHODS: A total of 80 living liver donors participated in this study. Each patient underwent both MRS and intraoperative biopsy for evaluation of liver fatty content. MRS was performed using 1.5-T magnetic resonance imaging and placed in segments 2-4, 5-8, and left lateral segment for each donor. Accuracy was assessed through receiver operating characteristic curve analysis. Sensitivity and specificity of MRS fat fractions were also calculated. RESULTS: Eighty living-donor liver transplantation donors were enrolled in this study. There was no fatty liver in 59 subjects (73.8%), 5% to 10% fatty liver in 17 subjects, 11% to 15% fatty liver in 3 subjects, and >16% fatty liver in 1 subject. MRS fat fraction showed excellent parameters to predict between normal liver and fatty liver groups (1.85% ± 0.98, 8.13% ± 3.52, respectively; P < .0001). Linear regression between MRS fat fraction and pathology grading showed high correlation (R(2) = 0.7092). Pearson correlation revealed high correlation between MRS and pathology results (r = 0.936), poor correlation between body mass index and pathology results (r = 0.390). The sensitivity and specificity for detection of liver steatosis in MRS fat fraction were 95.2% and 98.3%, respectively. CONCLUSION: (1)H MRS fat fraction is a highly precise and accurate method in quantification of hepatic steatosis for the living donor and can be finished in a single breath-hold.

Magnetic resonance fat quantification in living donor liver transplantation.

OBJECTIVE: Hepatic steatosis can cause substantial problems for both donors and recipients in living donor liver transplantation (LDLT). The aim of this study is to evaluate the accuracy of the magnetic resonance IDEAL (iterative decomposition of water and fat with echo asymmetry and least squares estimation) sequence in quantifying the liver fat during LDLT. MATERIALS AND METHODS: A total of 63 liver donors (29 men and 34 women ranging from 18 to 47 years old with a mean age of 30) who received both magnetic resonance imaging (MRI) and intraoperative liver biopsy were enrolled in this study. MR IDEAL IQ sequences were performed by 1.5-T MRI (Discovery 450; GE Healthcare, Milwaukee, Wis, United States) to estimate the liver fatty content. Accuracy was assessed through linear regression between fat fraction image and pathology grading. Sensitivity and specificity of MR IDEAL IQ fat fractions were also calculated. RESULTS: A total of 63 LDLTs were performed and with pathology grading. No fatty content was found in 48 donors (76.2%; group 1), 5% to 10% fatty liver in 11 donors (17.4%; group 2), 11% to 15% fatty liver in 2 donors (3.2%; group 3), and >16% fatty change in 2 donors (3.2%; group 4). MR IDEAL fat fraction results were excellent in prediction of the normal and fatty content and with good correlation with the pathology grading (2.9 ± 0.9, 8.3 ± 4.2, P < .0001). Linear regression between IDEAL image and pathology grading indicated a high accuracy rate (R(2) = 0.813, R(2) = 0.9286) for all 4 groups. The sensitivity and specificity for detection of liver steatosis in MRI fat fraction image were 100% and 77.1% (P < .0001, 95% confidence interval 0.000-1.000). CONCLUSION: MR IDEAL IQ sequencing is a highly precise and accurate method in quantifying hepatic steatosis for the living donor.

Magnetic resonance cholangiography in living donor liver transplantation: comparison of preenhanced and post-gadolinium-enhanced methods.

OBJECTIVE: The purpose of this study was to evaluate the image quality and diagnostic accuracy of postgadolinium complex of diethylenetriaminepentaacetic acid (GD-DTPA)-enhanced magnetic resonance cholangiography (MRC) in donor selection. MATERIALS AND METHODS: Donors (n=228) with both preoperative MRC and intraoperative cholangiography (IOC) were enrolled in this study. MRC pre- and post-GD-DTPA enhancement were performed using 1.5-T magnetic resonance imaging. The signal-to-noise ratio (SNR) of liver parenchyma and contrast-to-noise ratio of bile duct, as well as the contrast between bile duct and liver parenchyma, were calculated. The biliary anatomy correlation with the IOC during hepatectomy and patient prognosis were also evaluated. RESULTS: Quantitative results of the SNR of the liver parenchyma post-GD-DTPA were statistically significantly lower than preenhanced MRC (2.69 times reduced from the preenhanced MRC). The contrast of the bile duct and liver parenchyma in post-GD-DTPA were significantly higher than the preenhancement MRC. The anatomic diagnostic accuracy rate of post-GD-DTPA MRC was 92.9%. The sensitivity and specificity of GD-PTPA MRC were 85% and 96%, respectively. GD-DTPA-enhanced MRC has higher accuracy than the preenhanced MRC (92.9% vs 75%). The concurrence between GD-DTPA-enhanced MRC and IOC were commendable (kappa=0.9). The posttransplant biliary complication rate was 5.5%, and the 3-year survival rate was 91.2% in the recipients. CONCLUSION: GD-DTPA, a paramagnetic metal, can shorten the T1 and T2 relaxation values of surrounding protons. This decreases the signal of the liver parenchyma and brightens the biliary anatomy. It can improve the image quality of MRC and increase the diagnostic accuracy of the biliary tract classification. It is mandatory in the "donor and recipient surgery during the LDLT".

Idiopathic multicentric osteolysis with nephropathy.

Idiopathic multicentric osteolysis is a rare syndrome that manifests with progressive loss of carpal and tarsal bones in childhood. Affected children have arthritic-like episodes, followed by progressive deformities, radiographic osteolytic changes, and variable degrees of disability. A rare form of this disease (type III, sporadic) is associated with serious nephropathy. We present the first reported case of type III idiopathic multicentric osteolysis in a Chinese woman. The patient, a 34-year-old woman with normal mental development and no family history of bone or kidney disease, presented with a 4-day history of nausea and vomiting. She had shortening and swelling of the hands, which had occurred in childhood and persisted at the time of admission. X-ray studies showed disappearance of the carpal bones, and multiple osseous erosions of the tarsal bones. Hypertension, severe azotemia, and metabolic acidosis were also noted. Advanced renal disease was documented after a series of investigations, including renal biopsy. She is now dialysis-dependent. This case illustrates the importance of early diagnosis and management of idiopathic multicentric osteolysis with nephropathy.