An evolutionarily conserved ubiquitin ligase drives infection and transmission of flaviviruses.

Mosquito-borne flaviviruses such as dengue (DENV) and Zika (ZIKV) cause hundreds of millions of infections annually. The single-stranded RNA genome of flaviviruses is translated into a polyprotein, which is cleaved equally into individual functional proteins. While structural proteins are packaged into progeny virions and released, most of the nonstructural proteins remain intracellular and could become cytotoxic if accumulated over time. However, the mechanism by which nonstructural proteins are maintained at the levels optimal for cellular fitness and viral replication remains unknown. Here, we identified that the ubiquitin E3 ligase HRD1 is essential for flaviviruses infections in both mammalian hosts and mosquitoes. HRD1 directly interacts with flavivirus NS4A and ubiquitylates a conserved lysine residue for ER-associated degradation. This mechanism avoids excessive accumulation of NS4A, which otherwise interrupts the expression of processed flavivirus proteins in the ER. Furthermore, a small-molecule inhibitor of HRD1 named LS-102 effectively interrupts DENV2 infection in both mice and Aedes aegypti mosquitoes, and significantly disturbs DENV transmission from the infected hosts to mosquitoes owing to reduced viremia. Taken together, this study demonstrates that flaviviruses have evolved a sophisticated mechanism to exploit the ubiquitination system to balance the homeostasis of viral proteins for their own advantage and provides a potential therapeutic target to interrupt flavivirus infection and transmission.

A naturally isolated symbiotic bacterium suppresses flavivirus transmission by Aedes mosquitoes.

The commensal microbiota of the mosquito gut plays a complex role in determining the vector competence for arboviruses. In this study, we identified a bacterium from the gut of field Aedes albopictus mosquitoes named Rosenbergiella sp. YN46 (Rosenbergiella_YN46) that rendered mosquitoes refractory to infection with dengue and Zika viruses. Inoculation of 1.6 × 103 colony forming units (CFUs) of Rosenbergiella_YN46 into A. albopictus mosquitoes effectively prevents viral infection. Mechanistically, this bacterium secretes glucose dehydrogenase (RyGDH), which acidifies the gut lumen of fed mosquitoes, causing irreversible conformational changes in the flavivirus envelope protein that prevent viral entry into cells. In semifield conditions, Rosenbergiella_YN46 exhibits effective transstadial transmission in field mosquitoes, which blocks transmission of dengue virus by newly emerged adult mosquitoes. The prevalence of Rosenbergiella_YN46 is greater in mosquitoes from low-dengue areas (52.9 to ~91.7%) than in those from dengue-endemic regions (0 to ~6.7%). Rosenbergiella_YN46 may offer an effective and safe lead for flavivirus biocontrol.

Risk factor for the development of surgical site infection following ileostomy reversal: a single-center report.

PURPOSE: Postoperative surgical site infection (SSI) is not uncommon in patients with ileostomy reversal. The appropriate index to predict the postoperative SSI in these individuals remains unclear. The aim of this study is to evaluate the risk factor for SSI after ileostomy reversal. METHODS: A consecutive cohort of 201 patients who underwent elective ileostomy reversal between January 2015 and January 2020 were retrospectively analyzed. Patients were divided into two groups: SSI group and non-SSI group. Univariate and multivariate analyses were conducted to identify risk factors for postoperative SSI. RESULTS: Postoperative SSI occurred in 37 (18.4%) patients. Compared with the non-SSI group, patients in SSI group had higher incidence of nutrition risk (56.77% vs 39.02%, P = 0.049), higher C-reactive protein (CRP) level (10.81 ± 16.49 vs 4.86 ± 4.14 mg/L, P < 0.001), and longer postoperative hospital stay (13.08 ± 3.71 vs 7.47 ± 2.38 days, P < 0.001). By analyzing the receiver-operating characteristic (ROC) curve, CRP have the value in predicting the occurrence of SSI. The areas under the ROC curves of CRP for SSI was 0.671 (95% confidence interval 0.568-0.774, P = 0.001) with an optimal diagnostic cut-off value of 8.0 mg/L. By the univariate and multivariate analyses, preoperative C-reactive protein (CRP) ≥ 8 mg/L(P < 0.001) and conventional linear closure method (P = 0.004) were independent risk factors for postoperative SSI. CONCLUSIONS: Preoperative CRP levels can be served as a predictive index for postoperative SSI after stoma reversal. Purse-string closure technique is the treatment of choice to minimize stoma site SSI in patients with stoma reversal.

A mosquito salivary protein promotes flavivirus transmission by activation of autophagy.

Transmission from an infected mosquito to a host is an essential process in the life cycle of mosquito-borne flaviviruses. Numerous studies have demonstrated that mosquito saliva facilitates viral transmission. Here we find that a saliva-specific protein, named Aedes aegypti venom allergen-1 (AaVA-1), promotes dengue and Zika virus transmission by activating autophagy in host immune cells of the monocyte lineage. The AG6 mice (ifnar1-/-ifngr1-/-) bitten by the virus-infected AaVA-1-deficient mosquitoes present a lower viremia and prolonged survival. AaVA-1 intracellularly interacts with a dominant negative binder of Beclin-1, known as leucine-rich pentatricopeptide repeat-containing protein (LRPPRC), and releases Beclin-1 from LRPPRC-mediated sequestration, thereby enabling the initialization of downstream autophagic signaling. A deficiency in Beclin-1 reduces viral infection in mice and abolishes AaVA-1-mediated enhancement of ZIKV transmission by mosquitoes. Our study provides a mechanistic insight into saliva-aided viral transmission and could offer a potential prophylactic target for reducing flavivirus transmission.

The Application of Spleen-Preserving Splenic Regional Laparoscopic Lymphadenectomy with Spleen Kept In Situ and Laparotomy with Spleen Lifted Out of the Abdomen for Locally Advanced Proximal Gastric Cancer: A Retrospective Study.

BACKGROUND AND PURPOSE: Findings whether laparoscopic lymphadenectomy with spleen kept in situ or laparotomy with spleen lifted out of the abdomen is more effective remain inconclusive. This study is aimed at comparing outcomes of spleen-preserving splenic regional laparoscopic lymphadenectomy with spleen kept in situ versus laparotomy with spleen lifted out of the abdomen for locally advanced proximal gastric cancer. METHODS: Data from patients with locally advanced proximal gastric cancer were collected from January 2011 to January 2014. A total of 246 patients were identified who received D2 radical total gastrectomy together with spleen-preserving splenic regional lymphadenectomy. Of those patients, 87 patients underwent laparoscopic splenic regional lymphadenectomy with spleen kept in situ (LSKS-SRLA) and 159 patients underwent laparotomy with spleen lifted out of the abdomen (LSLA-SRLA). Surgical outcomes and long-term outcomes were compared between the two groups. RESULTS: The total number of lymph node dissection, intraoperative blood loss volume, intraoperative injury cases, and postoperative complications had no statistically significant difference between the two groups. The number of splenic regional lymph node dissections was 3.90 ± 1.05 per case in the LSLA-SRLA group and 2.89 ± 1.04 in the LSKS-SRLA group. The operation time, length of the incision, and hospital days were shorter in the LSKS-SRLA group. The total recurrence and metastatic rates and 3-year cumulative survival rate had no statistically significant difference between the two groups. CONCLUSIONS: Similar long-term outcomes were achieved in the LSKS-SRLA and LSLA-SRLA groups for locally advanced proximal gastric cancer. However, in the aspects of surgical time, length of incision, and postoperative recovery, the LSKS-SRLA group had obvious advantages.

Host serum iron modulates dengue virus acquisition by mosquitoes.

A blood meal is the primary route through which mosquitoes acquire an arbovirus infection. Blood components or their metabolites may regulate the susceptibility of mosquitoes to arboviruses. Here we report that serum iron in human blood influences dengue virus acquisition by mosquitoes. Dengue virus acquisition by Aedes aegypti was inversely correlated with the iron concentration in serum from human donors. In a mouse-mosquito acquisition model, iron supplementation reduced dengue virus prevalence and viral load, whereas neutralization of serum iron facilitated dengue virus infection in A. aegypti mosquitoes. Of note, mosquitoes feeding on iron-deficient (sideropenic) mice exhibited a higher prevalence of dengue virus. Reversal of the sideropenic status of hosts largely reduced dengue virus acquisition and infection by mosquitoes. Serum iron, rather than haem-bound iron, was utilized by the mosquito iron metabolism pathway to boost the activity of reactive oxygen species in the gut epithelium, subsequently inhibiting infection by dengue virus. On the basis of these results, a status of iron deficiency in the human population might contribute to the vectorial permissiveness to dengue virus, thereby facilitating its spread by mosquitoes.

Laparoscopy Combined with Enhanced Recovery Pathway in Ileocecal Resection for Crohn's Disease: A Randomized Study.

BACKGROUND AND AIMS: Laparoscopic approach is recommended as the first-choice option for simple ileocecal resections. However, there are no randomized trials that have focused on patients with Crohn's disease (CD) treated by laparoscopy and enhanced recovery pathway. The aim of the present study is to prospectively evaluate the feasibility, safety, and short-term outcomes of laparoscopy with enhanced recovery pathway for CD patients undergoing ileocecal resection. METHODS: A consecutive cohort of 32 CD patients who underwent laparoscopic ileocecal resection between December 2015 and December 2016 was randomized to enhanced recovery after surgery (ERAS) group or standard care group. Primary outcome was total postoperative hospital stay. Secondary outcomes were time to first flatus and stool, pain scores, morbidity, reoperation rate, readmission rate, and in-hospital costs. RESULTS: Compliance with the ERAS was high for all items (≥90%) except the items of abdominal drains and early fluid intake. A significantly earlier return of bowel function was observed in the ERAS group. Compared with the standard care group, patients in the ERAS group had shorter postoperative hospital stay and lower in-hospital costs (5.19 ± 1.28 versus 9.94 ± 3.33 days, P < 0.001; 2.70 ± 0.50 versus 3.73 ± 0.75 ten thousand RMB, P < 0.001, respectively). Other parameters did not show any significant differences between the two groups. CONCLUSIONS: Laparoscopic approach within an ERAS perioperative care program is a safe and effective treatment combination for CD patients requiring ileocecal resection. This study is registered at ClinicalTrials.gov (NCT02777034).

Glasgow prognostic score is a practical predictive index for postoperative intra-abdominal septic complications after bowel resection in Crohn's disease patients.

PURPOSE: Postoperative intra-abdominal septic complications (IASCs) are not uncommon in patients with Crohn's disease (CD). The appropriate index to predict postoperative IASCs in these individuals remains unknown. This study investigates whether the inflammation-based Glasgow prognostic score (GPS) is predictive in the setting of postoperative IASC CD patients who underwent elective bowel resection. METHODS: A consecutive cohort of 163 CD patients who underwent elective intestinal resection from July 2012 to March 2016 was retrospectively analyzed. Patients were divided into two GPS groups, one lower and one higher. The GPS was defined by serum levels of C-reactive protein and albumin. Univariate and multivariate analyses were conducted to identify risk factors for postoperative IASCs. RESULTS: Postoperative IASCs occurred in 25 (15.3%) patients. Compared with patients in the lower GPS group, patients with a higher GPS had a higher incidence of postoperative IASCs (9.85 vs. 38.71%, P < 0.001) and experienced longer postoperative hospital stay (10.53 ± 7.00 vs. 15.71 ± 9.17, P = 0.001). Univariate and multivariate analyses revealed preoperative GPS [odds ratio (OR) 5.016, 95% confidence interval (CI) 1.134-22.193, P = 0.034] and penetrating behavior (OR 4.495, 95% CI 1.377-14.670, P = 0.013) to be independent risk factors for postoperative IASCs. CONCLUSIONS: A preoperative GPS can serve as a useful index for predicting manifestation of postoperative IASCs after bowel resection in patients with CD. Perioperative optimization is required to improve postoperative outcomes for patients with higher GPS.

Laparoscopy-Assisted versus Open Hepatectomy for Live Liver Donor: Systematic Review and Meta-Analysis.

OBJECTIVE: To assess the feasibility, safety, and potential benefits of laparoscopy-assisted living donor hepatectomy (LADH) in comparison with open living donor hepatectomy (ODH) for liver transplantation. BACKGROUND: LADH is becoming increasingly common for living donor liver transplant around the world. We aim to determine the efficacy of LADH and compare it with ODH. METHODS: A systematic search on PubMed, Embase, Cochrane Library, and Web of Science was conducted in May 2017. RESULTS: Nine studies were suitable for this analysis, involving 979 patients. LADH seemed to be associated with increased operation time (WMD = 24.85 min; 95% CI: -3.01~52.78, P = 0.08), less intraoperative blood loss (WMD = -59.92 ml; 95% CI: -94.58~-25.27, P = 0.0007), similar hospital stays (WMD = -0.47 d; 95% CI: -1.78~0.83, P = 0.47), less postoperative complications (RR = 0.70, 95% CI: 0.51~0.94, P = 0.02), less analgesic use (SMD = -0.22; 95% CI: -0.44~-0.11, P = 0.04), similar transfusion rates (RR = 0.82; 95% CI: 0.24~3.12, P = 0.82), and similar graft weights (WMD = 7.31 g; 95% CI: -23.45~38.07, P = 0.64). CONCLUSION: Our results indicate that LADH is a safe and effective technique and, when compared to ODH.

Safety and Efficacy of Exclusive Enteral Nutrition for Percutaneously Undrainable Abdominal Abscesses in Crohn's Disease.

BACKGROUND: The percutaneously undrainable abdominal abscesses in Crohn's disease (CD) are not uncommon. The treatment protocol is still under debate. This study was conducted to assess the safety and efficacy of exclusive enteral nutrition (EEN) for percutaneously undrainable abscesses in CD. METHODS: A consecutive cohort of 83 CD patients with percutaneously undrainable abdominal abscesses between January 2011 and June 2015 was retrospectively analyzed. They were divided into the EEN group and the non-EEN group. RESULTS: The cumulative surgical rate was significantly lower in the EEN group than in the non-EEN group (P = 0.001). Fifteen percent patients treated with EEN avoided surgery. EEN (P = 0.002) was associated with a decreased need for surgery. Previous abdominal surgery (P = 0.009) and abscess diameter > 3 cm (P = 0.022) were associated with an increased need for operation. EEN increased the albumin level, while decreased ESR and CRP significantly for patients requiring surgery. The risk of postoperative intra-abdominal septic complications (P = 0.036) was significantly lower in the EEN group compared with the non-EEN group. CONCLUSIONS: EEN is feasible in CD patients presenting with percutaneously undrainable abdominal abscesses. It is associated with a reduction in surgical rate, optimized preoperative condition, and improved postoperative outcomes in these specific groups of patients.

Body mass index is a practical preoperative nutritional index for postoperative infectious complications after intestinal resection in patients with Crohn's disease.

The patients with Crohn's disease (CD) are often accompanied with nutritional deficiencies. Compared with other intestinal benign disease, patients with CD have the higher risk of developing postoperative complications following intestinal resection. The aim of this study was to investigate the risk factors for postoperative infectious complications (PICs) after intestinal resection for CD, as well as search a practical preoperative nutritional index for PICs in patients with CD. A total of 122 patients who underwent intestinal resection for CD during 2011 to 2015 were retrospectively analyzed. After operation, 28 (22.95%) patients experienced PICs. Compared with the non-PICs group, the patients with PICs have the lower preoperative body mass index (BMI) (16.96 ±â€Š2.33 vs 19.53 ±â€Š2.49 kg/m, P < .001), lower albumin (ALB) (33.64 ±â€Š5.58 vs 36.55 ±â€Š5.69 g/L, P = .013), higher C-reactive protein (CRP) level (30.44 ±â€Š37.06 vs 15.99 ±â€Š33.30 mg/L, P = .052), and longer hospital stay (22.64 ±â€Š9.93 vs 8.90 ±â€Š4.32 days, P < .001). By analyzing the receiver-operating characteristic (ROC) curve, BMI have better value in predicting the occurrence of PICs than ALB. The areas under the ROC curves of BMI for PICs was 0.784 (95% confidence interval 0.690-0.878, P < .001) with an optimal diagnostic cut-off value of 17.5 kg/m. In the univariate and multivariate analysis, BMI < 17.5 kg/m (P = .001), ALB < 33.6 g/L (P = .024), CRP ≥ 10 mg/L (P = .026) were risk factors for PICs. Patients with a lower preoperative BMI (BMI < 17.5 kg/m) had a 7.35 times greater risk of PICs. Therefore, preoperative BMI could be regarded as a practical preoperative nutritional index for evaluating the nutritional preparation sufficiency before CD operations. Preoperative treatment with the aim of reducing CRP level and improving the patient's nutritional status may be helpful to reduce the rate of PICs.

Efficacy of Magnetic Sphincter Augmentation versus Nissen Fundoplication for Gastroesophageal Reflux Disease in Short Term: A Meta-Analysis.

Background. The efficacy of Magnetic Sphincter Augmentation (MSA) and its outcomes for Gastroesophageal Reflux Disease (GERD) are uncertain. Therefore, we aimed to summarize and analyze the efficacy of two treatments for GERD. Methods. The meta-analysis search was performed, using four databases. All studies from 2005 to 2016 were included. Pooled effect was calculated using either the fixed or random effects model. Results. A total of 4 trials included 624 patients and aimed to evaluate the differences in proton-pump inhibitor use, complications, and adverse events. MSA had a shorter operative time (MSA and NF: RR = -18.80, 95% CI: -24.57 to -13.04, and P = 0.001) and length of stay (RR = -14.21, 95% CI: -24.18 to -4.23, and P = 0.005). Similar proton-pump inhibitor use, complication (P = 0.19), and severe dysphagia for dilation were shown in both groups. Although there is no difference between the MSA and NF in the number of adverse events, the incidence of postoperative gas or bloating (RR = 0.71, 95% CI: 0.54-0.94, and P = 0.02) showed significantly different results. However, there is no significant difference in ability to belch and ability to vomit. Conclusions. MSA can be recommended as an alternative treatment for GERD according to their short-term studies, especially in main-features of gas-bloating, due to shorter operative time and less complication of gas or bloating.

Toward the development of monoclonal antibody-based assays to probe virion-like epitopes in hepatitis B vaccine antigen.

Prophylactic vaccines against hepatitis B Virus (HBV) infection were produced in different expression systems under different processing conditions. Since the recombinant HBV surface antigen (HBsAg) in these vaccines is a cysteine-rich protein with 14 cysteines among a total of 226 amino acids, the epitopes are dependent on the formation of intra- and intermolecular disulfide bonds. A panel of 22 monoclonal antibodies (mAbs) were developed and evaluated with respect to their sensitivity to disulfide reduction treatment of recombinant HBsAg. Not surprisingly, different mAbs showed different degree of sensitivity to controlled HBsAg disulfide reduction. With a view to exploring the functionality of anti-HBsAg mAbs to be used in HBsAg quality analysis, in vitro neutralization activity for the mAbs was assessed. One of the mAbs tested, 5F11, which showed high sensitivity to the disulfide integrity in HBsAg, was shown also to be highly effective in neutralizing HBV in vitro. Conversely, 42B6, while exhibiting similar neutralization activity, showed comparable binding HBsAg with or without reduction treatment. Based on these mAb characteristics, a sandwich ELISA with 42B6 being the capture Ab and detection Ab was developed to quantify HBsAg (like a "mass" assay) during antigen bioprocessing or in vaccine products. In parallel, when 5F11 was used as the detection Ab (with the same capture Ab), the assay can be used to probe disulfide-dependent and virion-like epitopes in intermediates or final products of hepatitis B vaccine, serving as a surrogate marker for vaccine efficacy to elicit neutralizing antibodies. This approach enables the comparative epitope specific antigenicity analysis of HBsAg antigen preparations from different sources.

Do drug users in China who frequently receive detoxification treatment change their risky drug use practices and sexual behavior?

BACKGROUND: Relapse rates among treated drug users in China are high. We examined the associations between frequency of drug detoxification treatment and HIV-related risky drug practices and sexual behavior. METHODS: A cross-sectional study was conducted among drug users in two Anhui province detoxification centers in 2003. RESULTS: A total of 312 drug users were recruited. Seventy-seven percent of the subjects had ever received two or more detoxification treatments. The median number of detoxification treatments received was three, with an interquartile range of two to five treatments. More than 7 in 10 (72%) ever injected drugs; 19% shared needles and syringes in the past 30 days; 40% of drug users reported having both regular and commercial sex partners in the past year and 48% reported having only regular sex partners. Multiple Poisson regression analysis documented that the frequency of detoxification treatment was not associated with a decrease in drug practice (injection or sharing needles) and in unprotected sex. CONCLUSION: Drug users who frequently received detoxification treatment did not change their risky drug use practices and sexual behavior. Effective behavioral interventions and substitution maintenance treatment should become an integral part of detoxification programs in China.