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Soil carbon isotopes (δ13C) provide reliable insights for studying soil carbon turnover at a long-term scale. The Tibetan Plateau (TP), often referred as "the third pole of the earth", is highly sensitive to global climate change, and exhibits an early warning signal of global warming. Although many studies detected soil δ13C variability at site scales, there is still a knowledge gap existing in the spatial pattern of soil δ13C across the TP. In this study, we compiled a database of 198 topsoil δ13C observations from published literatures and used a modified multi-layer perceptron (MLP) neural network algorithm to predict the spatial pattern of topsoil δ13C and β (indicating the decomposition rate of soil organic carbon (SOC), calculated as δ13C divided by logarithmically converted SOC) at 500m resolution. Results showed that MLP model effectively predicted topsoil δ13C with a model efficiency of 0.72 and a root mean square error of 1.16‰. Topsoil δ13C varied significantly across different ecosystem types (p < 0.001) with a mean δ13C of –25.89 ± 1.15‰ (mean ± standard deviation) for forests, –24.91 ± 1.03‰ for shrublands, –22.95 ± 1.44‰ for grasslands, and –18.88 ± 2.37‰ for deserts. Furthermore, there was an increasing trend of predicted δ13C from the southeastern to the northwestern TP, likely linked to vegetation type and climatic conditions. β values were low in the eastern TP and higher in the northern and northwestern TP, indicating faster SOC turnover rate in the east TP compared to the north and northwest. This study represents the first effort to develop a fine resolution product of topsoil δ13C and β across the TP, which could provide an independent, data-driven benchmark for biogeochemical cycling models to study SOC turnover and terrestrial carbon-climate feedback over the TP under climate change. [ABSTRACT FROM AUTHOR]

Starch digestion in the small intestines of the dairy cow is low, to a large extent, due to a shortage of syntheses of α -amylase. One strategy to improve the situation is to enhance the synthesis of α -amylase. The mammalian target of rapamycin (mTOR) signalling pathway, which acts as a central regulator of protein synthesis, can be activated by leucine. Our objectives were to investigate the effects of leucine on the mTOR signalling pathway and to define the associations between these signalling activities and the synthesis of pancreatic enzymes using an in vitro model of cultured Holstein dairy calf pancreatic tissue. The pancreatic tissue was incubated in culture medium containing l -leucine for 3 h, and samples were collected hourly, with the control being included but not containing l -leucine. The leucine supplementation increased α -amylase and trypsin activities and the messenger RNA expression of their coding genes (P <0.05), and it enhanced the mTOR synthesis and the phosphorylation of mTOR, ribosomal protein S6 kinase 1 and eukaryotic initiation factor 4E-binding protein 1 (P <0.05). In addition, rapamycin inhibited the mTOR signal pathway factors during leucine treatment. In sum, the leucine regulates α -amylase and trypsin synthesis in dairy calves through the regulation of the mTOR signal pathways. [ABSTRACT FROM AUTHOR]

Objective: To investigate the relationship between dietary vitamin A intake and its sources in the first trimester and gestational diabetes mellitus (GDM). Methods: A prospective study was conducted to select women at 6-14 weeks of gestation in an obstetric clinic of a maternal and child health care medical institution in Chengdu in 2017. The types and quantities of food during the first trimester were collected by 3-day 24-hour dietary recalls. Dietary vitamin A intake was calculated based on the Chinese Food Composition Table (2018), and it was divided into animal and plant vitamin A intakes according to its food sources. An oral glucose tolerance test was performed at 24-28 weeks of gestation to diagnose GDM according to the Chinese guidelines for diagnosis and treatment of gestational diabetes mellitus (2014). According to the estimated average requirement (EAR) and recommended nutrient intake (RNI), dietary vitamin A intake was divided into low-level group (RNI). Animal and plant vitamin A intakes were divided into four groups (Q1-Q4) according to the quartile method, respectively. The association between dietary vitamin A intake, its different sources of vitamin A intake and GDM in the first trimester was analyzed by log-binomial regression models. Results: A total of 1 298 valid samples were finally included. The average dietary vitamin A intake, animal and plant vitamin A intakes in the first trimester were 341.1 (227.8-501.0) μgRAE/d, 139.3 (69.6-195.3) μgRAE/d and 184.2 (99.4-301.1) μgRAE/d, respectively. After adjusting for confounding factors, log-binomial regression analysis showed that the risk of GDM in high-level group of dietary vitamin A intake was lower than that in low-level group [ RR (95% CI ):0.53 (0.36-0.80)]. Pregnant women in the highest quartile of animal vitamin A intake had a lower risk of GDM than those in the lowest quartile [ RR (95% CI ):0.66 (0.47-0.95)]. No relationship between plant vitamin A intake and GDM was found. Conclusion: Dietary vitamin A intake in the first trimester is associated with the occurrence of GDM, and higher intake than RNI may reduce the risk of GDM. Higher vitamin A intake from animal-derived food is associated with decreased risk of GDM.

Objective: To explore the effects of dietary glycemic load (GL) during first trimester on the risk of gestational diabetes mellitus (GDM). Methods: A prospective study was conducted among healthy women with singleton pregnancy at 8-14 weeks of gestation in a maternity out-patient clinic of maternal-and-child health care institution in Chengdu, Sichuan province. Information on dietary intake during the first trimester was collected through a 3-day 24-hour dietary recall. Glycemic index (GI) values were obtained from China Food Composition Tables (Standard Edition) and International Tables of Glycemic Index and Glycemic Load Values (2008). Dietary GL and GLs of staple foods were calculated based on GI values and the amount of carbohydrate consumed per day. Diagnostic criteria of GDM was followed the Guidelines for Diagnosis and Treatment of Pregnancy Diabetes in China (2014), and used on participants who underwent an oral glucose tolerant test during 24-28 weeks of gestation. Log-binomial regression models were used to explore the associations between both quartiles of dietary GL, GLs of staple foods and the risks of GDM,respectively. Results: The medians of dietary GL and GL of staple foods were 145.70 (113.23-180.85) and 121.05 (89.08-155.70), respectively. The median GL of both rice and tubers were 73.14 (43.89-107.50) and 3.43 (0.00-9.84), respectively. After adjusting for the age at pregnancy, pre-pregnancy body mass index and other confounding factors, results of log-binomial regressions analysis showed that when compared with the lowest quartile of dietary GL group, the third and highest quartiles of dietary GL groups increased the risk of GDM ( RR =1.47, 95% CI : 1.20-1.80; RR =1.31, 95% CI : 1.04-1.64), respectively. Compared with the lowest quartile of GL of staple foods, the third and highest quartiles of GL of staple foods groups also increased the risk of GDM ( RR =1.28, 95% CI : 1.04-1.58; RR =1.27, 95% CI : 1.02-1.60), respectively. The third and highest quartiles of GL of rice groups increased the risk of GDM ( RR =1.30, 95% CI : 1.06-1.59; RR =1.28, 95% CI : 1.03-1.59), respectively, than the lowest quartile of GL of rice group. When compared with the lowest quartile of GL of tubers group, the highest quartile of GL of tubers group increased the risk of GDM ( RR =1.30, 95% CI : 1.09-1.54). However, we did not notice the effects of wheat GL and coarse grain GL on the risk of GDM. Conclusions: A positive association was found between dietary glycemic load and the risk of GDM. Higher dietary glycemic load, especially in rice and tubers during first trimester, seemed to have increased the risk of GDM.

This study aimed to investigate the effect of dietary supplementation with leucine and phenylalanine on pancreas development, enzyme activity, and related gene expression in male Holstein calves. Twenty male Holstein calves [1 d of age, 38 ± 3 kg of body weight (BW)] were randomly assigned to 1 of the following 4 treatment groups with 5 calves in each group: control, leucine supplementation (1.435 g/L of milk), phenylalanine supplementation (0.725 g/L of milk), and leucine and phenylalanine (1.435 + 0.725 g/L of milk). The diets were made isonitrogenous with the inclusion of alanine in each respective treatment. The feeding trial lasted for 8 wk, including 1 wk for adaption and 7 wk for the feeding experiment. Leucine tended to increase the concentration of total pancreatic protein (mg/kg of BW). Phenylalanine increased the concentrations of plasma insulin, cholecystokinin, and pancreatic DNA (mg/g) and the expression of trypsin gene but decreased the pancreatic protein:DNA ratio and tended to decrease the pancreas weight (g/kg of BW). No differences were observed in total pancreatic DNA (mg/pancreas and mg/kg of BW), pancreatic protein (mg/pancreas), or activities of α-amylase, trypsin, and lipase. The relative expression levels of the genes encoding α-amylase and lipase did not differ among the 4 groups. The supplementation of both leucine and phenylalanine showed an interaction on the pancreas weight (g and g/kg of BW) and a tendency of an interaction on the pancreatic protein concentration (mg/g of pancreas and mg/kg of BW) and the plasma glucose concentration. Leucine tended to increase the size of the pancreatic cells, whereas phenylalanine tended to increase the number of pancreatic cells. However, neither AA affected the activities of the pancreatic enzymes of the calves. These results indicate that leucine and phenylalanine supplementation in milk-fed Holstein calves differentially affect pancreatic growth and development., (Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

This study aimed to examine the temporal (hourly within a day and daily over the long term) effects of monensin on CH 4 emissions, ruminal fermentation, and in situ alfalfa degradation in dairy goats during dietary monensin supplementation by controlling the confounding effects of feed intake and ambient temperature. Six ruminally cannulated dairy goats were used, and they were housed in environmental chambers and fed a restricted amount of ration throughout the experiment. The experiment included a baseline period of 20 d followed by a treatment period of 55 d with 32 mg of monensin/d. During the whole experiment, CH 4 production was measured every 5 d, whereas fermentation characteristics and in situ alfalfa degradation were analyzed every 10 d. The CH 4 -depressing effect of monensin was time dependent on the duration of treatment, highly effective at d 5 but thereafter decreased gradually until d 55 even though CH 4 -suppressing effect still remained significant. The decreasing effects of monensin on ruminal acetate proportion and acetate to propionate ratio also faded over days of treatment, and the acetate proportion returned up to the pre-supplementation level on d 50. Monensin supplementation elevated ruminal propionate proportion and decreased the effective ruminal degradability of alfalfa NDF, but both measurements tended to recover over time. The postprandial increase rate of hourly CH 4 emissions was reduced, whereas that of propionate proportion was enhanced by monensin supplementation. However, the postprandial responses to monensin in CH 4 emission rates, ruminal VFA profiles, and in situ degradation kinetics declined with both hours after feeding and days of treatment. Our results suggest that the CH 4 -suppressing effect of monensin supplementation in goats was attributed to reductions in both ruminal feed degradation and acetate to propionate ratio, but those reductions faded with time, hours after feeding, and days of treatment., (Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

Background/aims: Hepatic artery stenosis (HAS) is a potentially life-threatening complication of liver transplantation because the associated mortality and morbidity rates are high. Surgical reconstruction was recommended as first choice of treatment and interventional radiologic techniques have been introduced recently. However, the mid- or long-term outcomes of HAS were unclear. The purpose of this study was to evaluate the efficacy of interventional therapy and clinical outcomes of HAS following liver transplantation., Methods: A retrospective analysis was performed for 20 cases of HAS documented by angiography from October 2003 to August 2007 at the authors' institution. All patients underwent transluminal interventional therapy including percutaneous transluminal angioplasty and endovascular stent placement. The technical results, hepatic artery patency and clinical outcome were reviewed., Results: All patients were treated with interventional management. Technical and immediate success was 100%. Of 8 patients with early HAS (within 1 month of transplantation), 1 underwent retransplantation due to deterioration of liver function. One died of acute liver failure waiting for retransplantation. Of 12 patients with late HAS (after 1 month of liver transplantation), 1 died of severe sepsis 38 days after transplantation. Five patients underwent late retransplantation due to ischemic-type biliary strictures or recurrent attacks of cholangitis. One of these patients died 11 days after retransplantation. The median follow-up of all 20 patients was 14.4 months after liver transplantation. The Kaplan-Meier curve of patency showed that cumulated primary patency of hepatic artery interventional treatment at 3, 6 and 12 months was 94, 87 and 79%, respectively. Two patients died of causes unrelated to HAS. Three patients developed recurrent HAS and were successfully treated with second interventional therapy. Eight patients (40%) developed ischemic-type biliary strictures and 7 underwent endoscopic treatment or percutaneous transhepatic cholangiodrainage. Graft function in 5 patients improved. The Kaplan-Meier curve of survival showed that the 1- and 2-year cumulated survival rates of early and late HAS were 87.5 and 43.8% and 81.5 and 61.1%, respectively. There was no significant difference in 1- and 2-year survival rates between early and late HAS (log-rank test, p = 0.928)., Conclusion: Interventional therapy is an effective treatment for both early and late HAS with excellent short- and mid-term outcomes, while without irreversible graft dysfunction resulted from HAS. However, the patients have a high incidence of ischemic-type biliary lesions., ((c) 2008 S. Karger AG, Basel.)

From Oct. 1989 to Apr. 1990, 16 patients with colorectal carcinoma undergoing elective radical resection were randomly divided into two groups to receive oral and combined (oral + i.v.) antimicrobials respectively. Patients in the oral group received preoperative oral gentamicin and metronidazole for two days, in the combined group oral medication was followed by the same antimicrobials intravenously during perioperative period. Quantitative bacterial cultures were performed before and after the regimen. Results showed that the preoperative prophylaxis with oral antimicrobial resulted in a significant reduction in the bacterial counts of the rectum contents in all the patients (P < 0.001). The NICs of gentamicin and metronidazole for E. coli and B. fragilis were found to be 2.31 micrograms/ml and 0.66 micrograms/ml respectively. The perioperative blood samples and the intraoperative tissue specimens were taken for gentamicin and metronidazole determination. In the oral group, effective concentration of metronidazole were found in serum and tissues but gentamicin was undetected. In the combined group, effective concentrations of both gentamicin and metronidazole were detected. According to our results, the short-term preoperative oral medications combined with perioperative intravenous gentamicin and metronidazole prophylaxis appears to rational.

Thirty-five gastrofundic devascularization procedures were performed with the side-to-side CF stapler of Chinese manufacture for obliteration of oesophagogastric varices. Four patients were operated on as emergencies, six patients 2-3 weeks after control of bleeding by tamponade and the remaining twenty-five electively (including four patients who had not bled). There were two operative deaths, an operative mortality of 6 per cent. In all, 30 patients have been followed, 20 for 1-3 years and 10 for less than 1 year. Twenty-five patients had postoperative barium meal examination. The varices were ameliorated in 19, not changed in 5 and exacerbated in 1. Nine patients rebled and of these, two died. The stapler is used in devascularization to interrupt intramural varices in the oesophagocardiac region. It must be emphasized that its use is only a part of the devascularization procedure. When used alone devascularization is not complete. The side-to-side stapler appears to be a convenient, safe and rational instrument for use in devascularization.

Forty rectal carcinoma subjected to anterior resection using GF stapler during November 1979-March 1983 were reviewed. 32 were radical resections with the remaining 8 for palliation. 36 (90%) could be traced. 23/32 (73%) of the radical resection group survived for more than 5 years. Long-term follow-up showed that neither local recurrence nor 5 year survival was stapler-related. A stapler may facilitate the performance of a low anterior resection, but it is merely a form of technical improvement. Therefore, the principles of radical resection should still be strictly observed and indications for anterior resection should not be unconditionally extended.