Laparoscopic intraperitoneal onlay mesh (IPOM) with fascial repair (IPOM-plus) for ventral and incisional hernia: a systematic review and meta-analysis

PURPOSE

Despite advancements in laparoscopic ventral hernia repair (LVHR) using the intraperitoneal onlay mesh technique (sIPOM), recurrence remains a common postoperative complication. The objective of this systematic review and meta-analysis is to compare the efficacy of defect closure (IPOM-plus) versus non-closure in ventral and incisional hernia repair. The aim is to determine which technique yields better outcomes in terms of reducing recurrence and complication rates.

METHODS

A comprehensive literature review was conducted in the PubMed, Web of Science, Cochrane Library, Embase, and ClinicalTrials.gov databases from their inception until October 1, 2022, to identify all online English publications that compared the outcomes of laparoscopic ventral hernia repair with and without fascia closure.

RESULTS

Three randomized controlled trials (RCTs) and eleven cohort studies involving 1585 patients met the inclusion criteria. The IPOM-plus technique was found to reduce the recurrence of hernias (OR = 0.51, 95% CI [0.35, 0.76], p < 0.01), seroma (OR = 0.48, 95% CI [0.32, 0.71], p < 0.01), and mesh bulging (OR = 0.08, 95% CI [0.01, 0.42], p < 0.01). Subgroup analysis revealed that body mass index (BMI) (OR = 0.43, 95% CI [0.29, 0.65], p < 0.0001), type of article (OR = 0.51, 95% CI [0.35, 0.76], p = 0.0008 < 0.01), geographical location (OR = 0.54, 95% CI [0.36, 0.82], p = 0.004 < 0.01), follow-up time (OR = 0.50, 95% CI [0.34, 0.73], p = 0.0004 < 0.01) had a significant influence on the postoperative recurrence of the IPOM-plus technique.

CONCLUSION

The IPOM-plus technique has been shown to greatly reduce the occurrence of recurrence, seroma, and mesh bulging. Overall, the IPOM-plus technique is considered a safe and effective procedure. However, additional randomized controlled studies with extended follow-up periods are necessary to further evaluate the IPOM-plus technique.

The Causal Association Between Blood Lead and Sleep Disorders: Evidence from National Health and Nutrition Examination Survey and Mendelian Randomization Analysis

BACKGROUND

Poor sleep quality is a global public health concern. This study aimed to identify the risk factors for sleep disorders and clarify their causal effects.

METHODS

Data were obtained from the National Health and Nutrition Examination Survey (NHANES) and Mendelian randomization (MR)-Base databases. Baseline characteristics of individuals with and without sleep disorders were compared. A multivariate logistic regression analysis was performed to calculate the effects of each variable on sleep disorders. Causal effects of blood lead levels and hypertension on sleep disorders were assessed using MR analysis.

RESULTS

In total, 3660 individuals were enrolled in the study. The prevalence of self-reported sleep disorders was 26.21%. Serum lead level, serum mercury level, serum retinol level, prevalence of hypertension, and daily vigorous work duration were significantly higher for those in the sleep disorders group than the control group. After adjusting for various covariates, the effects of serum lead and hypertension on sleep disorders were stable from logistic regression models 1-4. MR analysis showed that blood lead levels were causally related to the risk of sleep disorders (odds ratio (OR) = 1.09, 95% confidence interval (CI) 1.01-1.17, P = 0.030). There was no causal link between elevated blood pressure and sleep disorders (OR = 0.99, 95% CI 0.94-1.04, P = 0.757). Goodness-of-fit tests and sensitivity analyses were used to verify the reliability of the results.

CONCLUSIONS

Blood lead is positively and causally associated with an increased risk of sleep disorders. These findings provide a novel perspective regarding sleep protection. Taking effective measures to reduce lead exposure may significantly improve sleep health.

Relationship of weight change patterns from young to middle adulthood with incident rheumatoid arthritis and osteoarthritis: a retrospective cohort study

Background

The relationship between weight change patterns and arthritis onset, specifically rheumatoid arthritis (RA) and osteoarthritis (OA), is unclear. We examined the association between weight changes from young adulthood to midlife and arthritis onset.

Methods

Using data from NHANES 1999-2018, participants with self-reported arthritis were selected. Age at diagnosis determined arthritis onset. Weight change patterns were based on BMI at age 25 and 10 years before the survey. Patterns were categorized as stable non-obese, non-obese to obese, obese to non-obese, and stable obese. Cox regression models and restricted cubic spline (RCS) analysis were employed, calculating hazard ratios (HRs) and 95% confidence intervals (CIs) considering covariates.

Results

Out of 20,859 participants (male 11,017, 52.82%), 4922 developed arthritis over a mean 8.66-year follow-up. Compared to stable non-obese individuals, the HRs for arthritis were 1.55 (95% CI=1.45 to 1.66, P < 0.0001) for non-obese to obese and 1.74 (95% CI=1.56 to 1.95, P < 0.0001) for stable obese. Those gaining 10-20 kg had a HR of 1.33 (95% CI=1.22 to 1.46, P < 0.0001), and gains >20 kg had a HR of 1.56 (95% CI=1.42 to 1.71, P < 0.0001), compared to stable weight (change within 2.5 kg). Identical results observed for OA and RA. RCS showed a nonlinear relationship between weight change and arthritis (all P < 0.01).

Conclusions

Stable obesity and weight gain during adulthood increase arthritis risk. Maintaining a non-obese weight throughout adult years might reduce arthritis risk in later life.

Adapting the inoculation methods of kiwifruit canker disease to identify efficient biocontrol bacteria from branch microbiome

Pseudomonas syringae pv. actinidiae (Psa), the bacterium that causes kiwifruit bacterial canker, is a common field occurrence that is difficult to control globally. Currently, exploring the resources for efficient biocontrol bacteria is a hot spot in the field. The common strategy for isolating biocontrol bacteria is to directly isolate biocontrol bacteria that can secrete diffusible antibacterial substances, most of which are members of Bacillus, Pseudomonas and Streptomycetaceae, from disease samples or soil. Here, we report a new approach by adapting the typical isolation methods of kiwifruit canker disease to identify efficient biocontrol bacteria from the branch microbiome. Using this unique approach, we isolated a group of kiwifruit biocontrol agents (KBAs) from the branch microbiome of Psa-resistant varieties. Thirteen of these showed no antagonistic activity in vitro, which depends on the secretion of antibacterial compounds. However, they exhibited antibacterial activity via cell-to-cell contacts mimicked by co-culture on agar plates. Through biocontrol tests on plants, two isolates, KBA13 and KBA19, demonstrated their effectiveness by protecting kiwifruit branches from Psa infection. Using KBA19, identified as Pantoea endophytica, as a representative, we found that this bacterium uses the type VI secretion system (T6SS) as the main contact-dependent antibacterial weapon that acts via translocating toxic effector proteins into Psa cells to induce cell death, and that this capacity expressed by KBA19 is common to various Psa strains from different countries. Our findings highlight a new strategy to identify efficient biocontrol agents that use the T6SS to function in an antibacterial metabolite-independent manner to control wood diseases.

Soil bacterium manipulates antifungal weapons by sensing intracellular type IVA secretion system effectors of a competitor

Soil beneficial bacteria can effectively inhibit bacterial pathogens by assembling contact-dependent killing weapons, such as the type IVA secretion system (T4ASS). It's not clear whether these antibacterial weapons are involved in biotrophic microbial interactions in soil. Here we showed that an antifungal antibiotic 2,4-DAPG production of the soil bacterium, Pseudomonas protegens can be triggered by another soil bacterium, Lysobacter enzymogenes, via T4ASS by co-culturing on agar plates to mimic cell-to-cell contact. We demonstrated that the induced 2,4-DAPG production of P. protegens is achieved by intracellular detection of the T4ASS effector protein Le1519 translocated from L. enzymogenes. We defined Le1519 as LtaE (Lysobacter T4E triggering antifungal effects), which specifically stimulates the expression of 2,4-DAPG biosynthesis genes in P. protegens, thereby protecting soybean seedlings from infection by the fungus Rhizoctonia solani. We further found that LtaE directly bound to PhlF, a pathway-specific transcriptional repressor of the 2,4-DAPG biosynthesis, then activated the 2,4-DAPG production. Our results highlight a novel pattern of microbial interspecies and interkingdom interactions, providing a unique case for expanding the diversity of soil microbial interactions.

"Triple-low" radiation dose bronchial artery CT angiography before bronchial artery embolisation: a feasibility study

AIM

To explore the feasibility of a "triple-low" dose (low tube voltage, low tube current, and low contrast agent volume) bronchial artery computed tomography (CT) angiography (CTA) to replace routine dose bronchial artery CTA before bronchial artery embolisation (BAE).

MATERIALS AND METHODS

CTA was obtained from 60 patients with body mass index (BMI) < 30 kg/m2 using a 256 multi-section iCT system, and they were divided into two groups: (1) group A: 100 kVp, 100 mAs, 50 ml contrast medium (CM); (2) group B: 120 kVp, automatic tube current modulation (ACTM), 80 ml CM. CT attenuation of the thoracic aorta, image noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated, and subjective image quality scores and traceability scores assessed. The effective radiation dose was calculated.

RESULTS

The radiation dose was reduced by 79.7% in group A compared to group B (p<0.05). The CT attenuation of the thoracic aorta was increased by approximately 13% in group A compared to group B (p<0.05). Higher image noise, lower SNR, and CNR were obtained in group A compared to group B (all p<0.05). Both subjective image quality scores and traceability scores did not differ between groups A and B (both p>0.05).

CONCLUSION

It is feasible to use the "triple-low" dose CTA protocol for patients with a body mass index (BMI) < 30 kg/m2. The radiation dose was reduced by 79.7%, and the dose of contrast medium was reduced by 37.5% to ensure the diagnostic value.

Unraveling genetic causality between type 2 diabetes and pulmonary tuberculosis on the basis of Mendelian randomization

BACKGROUND

The comorbidity rate between type 2 diabetes mellitus (T2DM) and pulmonary tuberculosis (PTB) is high and imposes enormous strains on healthcare systems. However, whether T2DM is causally associated with PTB is unknown owing to limited evidence from prospective studies. Consequently, the present study aimed to clarify the genetic causality between T2DM and PTB on the basis of Mendelian randomization (MR) analysis.

METHODS

Genetic variants for T2DM and PTB were obtained from the IEU OpenGWAS project. The inverse variance weighted method was used as the main statistical analysis method and was supplemented with MR-Egger, weighted median, simple mode, and weighted mode methods. Heterogeneity was analyzed using Cochran's Q statistic. Horizontal pleiotropy was assessed using the MR-PRESSO global test and MR-Egger regression. Robustness of the results was verified using the leave-one-out method.

RESULTS

A total of 152 independent single-nucleotide polymorphisms (SNPs) were selected as instrumental variables (IVs) to assess the genetic causality between T2DM and PTB. Patients with T2DM had a higher risk of PTB at the genetic level (odds ratio (OR) for MR-Egger was 1.550, OR for weighted median was 1.540, OR for inverse variance weighted was 1.191, OR for simple mode was 1.629, OR for weighted mode was 1.529). There was no horizontal pleiotropy or heterogeneity among IVs. The results were stable when removing the SNPs one by one.

CONCLUSIONS

This is the first comprehensive MR analysis that revealed the genetic causality between T2DM and PTB in the East Asian population. The study provides convincing evidence that individuals with T2DM have a higher risk of developing PTB at the genetic level. This offers a significant basis for joint management of concurrent T2DM and PTB in clinical practice.

Common autoimmune diseases and urticaria: the causal relationship from a bidirectional two-sample mendelian randomization study

Objective

The immune response assumes a pivotal role in the underlying mechanisms of urticaria pathogenesis. The present study delves into an investigation of the genetic causal connections between urticaria and prevalent autoimmune afflictions, notably rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), ulcerative colitis (UC), and Crohn's disease (CD).

Methods

A bidirectional two-sample Mendelian randomization (MR) analysis was conducted to investigate the causal relationships involving four autoimmune diseases and urticaria. The genome-wide association study (GWAS) summary data of four autoimmune disease were sourced from the IEU OpenGWAS database. The GWAS summary data for urticaria were derived from the Finnish consortium dataset. The principal analytical approach employed in this study was the random-effects inverse variance weighted (IVW) method. Subsequently, a series of sensitivity analyses were performed, encompassing assessments of heterogeneity, horizontal pleiotropy, outliers, "Leave-one-out" analyses, and tests for adherence to the assumption of normal distribution.

Results

The random-effects IVW analysis indicate a positive genetic causal association between RA and urticaria (P < 0.001, OR 95% CI = 1.091 [1.051-1.133]). Conversely, SLE, UC, and CD do not exhibit a significant genetic causal relationship with urticaria. The reverse MR analysis reveals a positive genetic causal linkage between urticaria and SLE (P = 0.026, OR 95% CI = 1.289 [1.031-1.612]). However, the analysis demonstrates no substantial genetic causal relationship between urticaria and RA, UC, or CD. Importantly, the genetic causal assessment absence of heterogeneity, horizontal pleiotropy, and outliers. Furthermore, it remains unaffected by any individual single nucleotide polymorphism (SNP), demonstrating adherence to a normal distribution.

Conclusion

This investigation establishing RA as a predisposing factor for urticaria. Moreover, urticaria as a plausible risk determinant for SLE. Heightened vigilance is recommended among RA patients to monitor the manifestation of urticaria within clinical settings. Similarly, individuals afflicted by urticaria should duly acknowledge the prospective susceptibility to SLE.

Retrospective analysis of medical emergencies in an oral emergency department

BACKGROUND

To retrospectively analyze the rescue of medical emergencies and critical patients in the oral emergency department in a hospital during the past 14 years; analyze the general condition of patients, their diagnosis, etiological factors, and outcomes of the disease, so as to improve the ability of oral medical staff to deal with emergencies; and optimize the emergency procedures and resource allocation in such departments.

MATERIAL AND METHODS

Data and related information of critical patient emergency rescue from the Emergency Department of the Hospital of Stomatology, Peking University from January 2006 to December 2019, were analyzed.

RESULTS

A total of 53 critical patients were rescued in the oral emergency department in the past 14 years, which is an average of four cases per year, with an incidence rate of 0.00506%. The main type of emergency included hemorrhagic shock and active hemorrhage, with the highest incidence being in the age group of 19-40 years old. Among these cases, 67.92% (36/53) developed emergency and critical diseases before visiting the oral emergency department and 41.51% (22/53) had systemic diseases. After rescue, a total of 48 patients (90.57%) had stable vital signs and 5 (9.43%) died.

CONCLUSIONS

Oral doctors and other medical staff should be able to rapidly identify medical emergencies in oral emergency departments and commence emergency treatment. The department should be equipped with relevant first-aid drugs and devices, and medical staff should be regularly trained in practical first-aid skills. Patients with oral and maxillofacial trauma, massive hemorrhage and systemic diseases should be evaluated and treated according to their conditions and systemic organ function to prevent and reduce medical emergencies.

Quorum quenching by a type IVA secretion system effector

Proteobacteria primarily utilize acyl-homoserine lactones (AHLs) as quorum-sensing signals for intra-/interspecies communication to control pathogen infections. Enzymatic degradation of AHL represents the major quorum-quenching mechanism that has been developed as a promising approach to prevent bacterial infections. Here we identified a novel quorum-quenching mechanism revealed by an effector of the type IVA secretion system (T4ASS) in bacterial interspecies competition. We found that the soil antifungal bacterium Lysobacter enzymogenes OH11 (OH11) could use T4ASS to deliver the effector protein Le1288 into the cytoplasm of another soil microbiome bacterium Pseudomonas fluorescens 2P24 (2P24). Le1288 did not degrade AHL, whereas its delivery to strain 2P24 significantly impaired AHL production through binding to the AHL synthase PcoI. Therefore, we defined Le1288 as LqqE1 (Lysobacter quorum-quenching effector 1). Formation of the LqqE1-PcoI complex enabled LqqE1 to block the ability of PcoI to recognize/bind S-adenosy-L-methionine, a substrate required for AHL synthesis. This LqqE1-triggered interspecies quorum-quenching in bacteria seemed to be of key ecological significance, as it conferred strain OH11 a better competitive advantage in killing strain 2P24 via cell-to-cell contact. This novel quorum-quenching also appeared to be adopted by other T4ASS-production bacteria. Our findings suggest a novel quorum-quenching that occurred naturally in bacterial interspecies interactions within the soil microbiome by effector translocation. Finally, we presented two case studies showing the application potential of LqqE1 to block AHL signaling in the human pathogen Pseudomonas aeruginosa and the plant pathogen Ralstonia solanacearum.

Assessing the feasibility of SUVindex (a metric derived from FDG PET/CT) for the diagnosis of polymyalgia rheumatica

AIM

To evaluate the feasibility of standard uptake value (SUV) index (ratio lesional maximum SUV [SUVmax] to liver mean SUV [SUVmean]) as a metabolic parameter for diagnosing polymyalgia rheumatica (PMR).

MATERIALS AND METHODS

A retrospective group of patients with PMR and controls with symptoms similar to PMR but diagnosed with other diseases. Semiquantitative and qualitative analysis of 2-[18F]-fluoro-2-deoxy-d-glucose (18F-FDG) uptake at 18 sites was undertaken for all patients. The diagnostic value of positron-emission tomography/computed tomography (PET/CT) for PMR was assessed by R software using logistic regression and a generalised additive model (GAM). All images were examined independently by two nuclear medicine physicians with extensive work experience.

RESULTS

The characteristic sites of PMR were the ischial tuberosity, interspinous bursa, periarticular hip, and symphysis pubis enthesis. The area under the curve (AUC) of the characteristic site SUV index was 0.930, and the best cut-off value was 1.685 with a sensitivity of 84.6% and a specificity of 92.6%. After adjusting for potential confounders, the probability of PMR diagnosis increased as the characteristic site SUV index increased and there was a nonlinear correlation between the two. When the characteristic site SUV index was ≥2.56, the probability of PMR gradually reached the threshold effect, which was as high as 90% or more.

CONCLUSION

The characteristic site SUV index is an independent factor for diagnosing PMR, and PMR should be highly suspected when it is ≥ 1.685. Nonetheless, it is important to note that these findings are based on an initial retrospective single-centre study and require external validation and further prospective evaluation before being translated into clinical practice.

Assembly of an active microbial consortium by engineering compatible combinations containing foreign and native biocontrol bacteria of kiwifruit

Assembling functional bacterial biocontrol consortia is expected to expand the scope and efficiency of biocontrol agents. Generally, bacterial interspecies interactions lead to incompatibility events, as bacteria can produce antibacterial compounds and/or assemble contact-dependent killing (CDK) devices. Here, we aimed to assemble a bacterial consortium comprising Lysobacter enzymogenes OH11 and Bacillus safensis ZK-1 for the synergistic control of bacterial and fungal diseases of kiwifruit. ZK-1, a native kiwifruit biocontrol bacterium, is effective against Pseudomonas syringae pv. actinidiae (Psa) that causes bacterial kiwifruit canker, but has weak antifungal activity. OH11 is a foreign kiwifruit biocontrol agent with strong antifungal activity. While OH11 was unable to produce anti-Gram-negative metabolites, this strain could utilize type IV secretion system as an antibacterial CDK weapon. We first observed that OH11 could inhibit growth of ZK-1 by generating diffusible anti-Gram-positive antibiotic WAP-8294A2, whereas ZK-1 failed to generate diffusible antibacterial compound to inhibit growth of OH11. To disrupt this interspecies incompatibility, we generated a transgenic OH11-derived strain, OH11W, by deleting the WAP-8294A2 biosynthetic gene and found that OH11W did not kill ZK-1. We further observed that when OH11W and ZK-1 were co-inoculated on agar plates, no CDK effect was observed between them, whereas co-culture of OH11W or ZK-1 with Psa on agar plates resulted in Psa killing, suggesting L. enzymogenes and B. safensis assemble antibacterial CDK weapons against bacterial pathogens, and these CDK weapons did not affect the compatibility between OH11W and ZK-1. Based on these findings, we assembled an OH11W/ZK-1 dependent consortium that was shown to be functional in controlling bacterial canker and several representative fungal diseases of kiwifruit.

RNA-binding Protein QKI Inhibits Osteogenic Differentiation Via Suppressing Wnt Pathway

BACKGROUND

Dysregulation of MSCs differentiation is associated with many pathophysiological processes. Genetically modified MSCs transplantation helps restore bone loss efficiently.

METHODS

BMSCs-specific QKI overexpressing and knockdown mice were built to explore QKI's role in bone formation and fat accumulation. Primary BMSCs with QKI overexpression and knockout were subjected to osteogenic and adipogenic differentiation. ALP staining and oil red O staining were performed to evaluate the differences between the groups. RNA immunoprecipitation was performed to identify the QKI-related pathway. QKI deficient BMSCs were transplanted into mice with glucocorticoid-induced osteoporosis to evaluate its therapeutic potential.

RESULTS

Mice harboring BMSC-specific transgenic QKI exhibited reduced bone mass, while BMSC-specific QKI-deficient mice showed an increase in bone mass. Osteogenic differentiation of QKI deficient BMSCs was promoted and adipogenic differentiation was inhibited, while QKI overexpression in BMSCs displayed the opposite effects. To define the underlying mechanisms, RIP sequencing was performed. Wnt pathway-related genes were the putative direct target mRNAs of QKI, Canonical Wnt pathway activation was involved in QKI's effects on osteogenic differentiation. RNA immunoprecipitation quantitative real-time Polymerase Chain Reaction (PCR) and RNA fluorescence in situ hybridization experiments further validated that QKI repressed the expressions of Wnt5b, Fzd7, Dvl3 and β-catenin via direct binding to their putative mRNA specific sites. Glucocorticoid-induced osteoporotic mice transplanted with QKI deficient BMSCs exhibited less bone loss compared with mice transplanted with control BMSCs.

CONCLUSIONS

QKI suppressed BMSCs osteogenic differentiation by downregulating the expressions of Wnt5b, Fzd7, Dvl3 and β-catenin. Loss of QKI in BMSCs transplantation may provide a new strategy for the treatment of orthopedic diseases such as osteoporosis.

Breast cancer diagnosis and prognosis using a high b-value non-Gaussian continuous-time random-walk model

AIM

To compare the diagnostic performance of mono-exponential model-derived apparent diffusion coefficient (ADC), continuous-time random-walk (CTRW) model-derived D_m, α, β and their combinations in discriminating malignancy of breast lesions, and investigate the association between model-derived parameters and prognosis-related immunohistochemical indices.

MATERIALS AND METHODS

A total of 85 patients with breast lesions (51 malignant, 34 benign) were analysed in this retrospective study. Clinical characteristics include oestrogen receptor (ER), progesterone receptor (PR), human epidermal receptor 2 (HER2), and Ki-67. The ADC was fitted using a mono-exponential model (b-values = 0, 800 s/mm²), while D_m, α, and β were fitted using a CTRW model. Independent Student's t-test and the Mann-Whitney U-test were used for the comparison of parameters. Discrimination performance was accomplished by receiver operating characteristic (ROC) analysis, and Spearman's correlation analysis was used to explore the association between immunohistochemical indices and diffusion parameters, the statistical significance level was p<0.05.

RESULTS

D_m and ADC demonstrated similar performance in differentiating malignant and benign lesions (AUC = 0.928 versus 0.930), while the combination of D_m, α, and β could improve the AUC to 0.969. The combined parameter generated by ADC, D_m, α, and β was effective in identifying the ER+/ER- and PR+/PR- patients. Temporal heterogeneity parameter α correlated significantly with the expression of PR.

CONCLUSION

Diffusion parameters derived from the CTRW model could effectively discriminate the malignancy of breast lesions. Meanwhile, the hormone receptor expression could be distinguished by combined diffusion parameters, and have the potential to reflect the prognosis.

Pharmacodynamic activity of BMS-986156, a glucocorticoid-induced TNF receptor-related protein agonist, alone or in combination with nivolumab in patients with advanced solid tumors

BACKGROUND

The success of immune checkpoint inhibitors has revolutionized cancer treatment options and triggered development of new complementary immunotherapeutic strategies, including T-cell co-stimulatory molecules, such as glucocorticoid-induced tumor necrosis factor receptor-related protein (GITR). BMS-986156 is a fully agonistic human immunoglobulin G subclass 1 monoclonal antibody targeting GITR. We recently presented the clinical data for BMS-986156 with or without nivolumab, which demonstrated no compelling evidence of clinical activity in patients with advanced solid tumors. Here, we further report the pharmacodynamic (PD) biomarker data from this open-label, first-in-human, phase I/IIa study of BMS-986156 ± nivolumab in patients with advanced solid tumors (NCT02598960).

MATERIALS AND METHODS

We analyzed PD changes of circulating immune cell subsets and cytokines in peripheral blood or serum samples collected from a dataset of 292 patients with solid tumors before and during treatment with BMS-986156 ± nivolumab. PD changes in the tumor immune microenvironment were measured by immunohistochemistry and a targeted gene expression panel.

RESULTS

BMS-986156 + nivolumab induced a significant increase in peripheral T-cell and natural killer (NK) cell proliferation and activation, accompanied by production of proinflammatory cytokines. However, no significant changes in expression of CD8A, programmed death-ligand 1, tumor necrosis factor receptor superfamily members, or key genes linked with functional parameters of T and NK cells were observed in tumor tissue upon treatment with BMS-986156.

CONCLUSIONS

Despite the robust evidence of peripheral PD activity of BMS-986156, with or without nivolumab, limited evidence of T- or NK cell activation in the tumor microenvironment was observed. The data therefore explain, at least in part, the lack of clinical activity of BMS-986156 with or without nivolumab in unselected populations of cancer patients.

Twitching Motility Assays of Lysobacter enzymogenes OH11 Under a Light Microscope

Bacterial twitching motility is a peculiar way of adherence and surface translocation on moist solid or semisolid surfaces. Although the twitching motility has been detected in various flagellated bacteria, such as Pseudomonas aeruginosa, it has been rarely detected in flagella-less bacteria like Lysobacter enzymogenes, a natural predator of filamentous fungi. Here, by using a strain OH11 of L. enzymogenes as a model system, we describe a convenient method for observing the twitching motility, with fewer steps and better repetition than conventional methods. This new method provides important technical support for the motile study of Lysobacter.

A Novel and Efficient Platform for Discovering Noncanonical Quorum-Quenching Proteins

Quorum sensing (QS) is a well-known chemical signaling system responsible for intercellular communication that is widespread in bacteria. Acyl-homoserine lactone (AHL) is the most-studied QS signal. Previously, bacterially encoded AHL-degrading enzymes were considered to be canonical quorum-quenching proteins that have been widely used to control pathogenic infections. Here, we report a novel platform that enabled the efficient discovery of noncanonical AHL quorum-quenching proteins. This platform initially asked bacteriologists to carry out comparative genomic analyses between phylogenetically related AHL-producing and non-AHL-producing members to identify genes that are conservatively shared by non-AHL-producing members but absent in AHL-producing species. These candidate genes were then introduced into recombinant AHL-producing E. coli to screen for target proteins with the ability to block AHL production. Via this platform, we found that non-AHL-producing Lysobacter containing numerous environmentally ubiquitous members encoded a conserved glycosyltransferase-like protein Le4759, which was experimentally shown to be a noncanonical AHL-quenching protein. Le4759 could not directly degrade exogenous AHL but rather recognized and altered the activities of multiple AHL synthases through protein-protein interactions. This versatile capability enabled Le4759 to block specific AHL synthase such as CarI from Pectobacterium carotovorum to reduce its protein abundance to suppress AHL synthesis, thereby impairing bacterial infection. Thus, this study provided bacteriologists with a unique platform to discover noncanonical quorum-quenching proteins that could be developed as promising next-generation drug candidates to overcome emerging bacterial antibiotic resistance. IMPORTANCE Targeting and blocking bacterial quorum sensing (QS), the process known as quorum quenching (QQ) is an effective mean to control bacterial infection and overcome the emerging antibiotic resistance. Previously, diverse QS signal-degradation enzymes are identified as canonical QQ proteins. Here, we provided a novel and universal platform that enabled to discover previously unidentified noncanonical QQ proteins that were unable to degrade acyl-homoserine lactone (AHL) but could block AHL generation by recognizing multiple AHL synthases via direct protein-protein interactions. Our findings are believed to trigger broad interest for bacteriologists to identify potentially widely distributed noncanonical QQ proteins that have great potential for developing next-generation anti-infectious drugs.

Loss of Flagella-Related Genes Enables a Nonflagellated, Fungal-Predating Bacterium To Strengthen the Synthesis of an Antifungal Weapon

Loss of flagellar genes causes a nonmotile phenotype. The genus Lysobacter consists of numerous environmentally ubiquitous, nonflagellated bacteria, including Lysobacter enzymogenes, an antifungal bacterium that is beneficial to plants. L. enzymogenes still has many flagellar genes on its genome, although this bacterium does not engage in flagella-driven motility. Here, we report that loss of certain flagellar genes allows L. enzymogenes to strengthen its evolutionarily gained capacity in fungal killing. To clarify why this bacterium loses flagellar genes during the evolutionary process, we cloned several representative flagellar genes from Xanthomonas oryzae, a flagellated, phylogenetically related species of Lysobacter, and introduced them individually into L. enzymogenes to mimic genomic reacquisition of lost flagellar genes. Heterogeneous expression of the three X. oryzae flagellar structural genes (Xo-motA, Xo-motB, Xo-fliE) and one flagellar regulatory gene (Xo-fleQ) remarkably weakened the bacterial capacity to kill fungal pathogens by impairing the synthesis of an antifungal weapon, known as the heat-stable antifungal factor (HSAF). We further investigated the underlying mechanism by selecting Xo-FleQ as the representative because it is a master transcription factor responsible for flagellar gene expression. Xo-FleQ inhibited the transcription of operon genes responsible for HSAF synthesis via direct binding of Xo-FleQ to the promoter region, thereby decreasing HSAF biosynthesis by L. enzymogenes. These observations suggest a possible genome and function coevolution event, in which an antifungal bacterium deletes certain flagellar genes in order to enhance its ability to kill fungi. IMPORTANCE It is generally recognized that flagellar genes are commonly responsible for the flagella-driven bacterial motility. Thus, finding nonflagellated bacteria partially or fully lost flagellar genes is not a surprise. However, the present study provides new insights into this common idea. We found that loss of either certain flagellar structural or regulatory genes (such as motA, motB, fliE, and fleQ) allows a nonflagellated, antifungal bacterium (L. enzymogenes) to stimulate its fungal-killing capacity, outlining a genome-function coevolution event, where an antifungal bacterium "smartly" designed its genome to "delete" crucial flagellar genes to coordinate flagellar loss and fungal predation. This unusual finding might trigger bacteriologists to reconsider previously ignored functions of the lost flagellar genes in any nonflagellated, pathogenic, or beneficial bacteria.

Development and validation of risk prediction models for stroke and mortality among patients with type 2 diabetes in northern China

BACKGROUND

Stroke is one of the leading causes of disability and mortality in patients with type 2 diabetes mellitus (T2DM). Risk models have been developed for predicting stroke and stroke-associated mortality among patients with T2DM. Here, we evaluated risk factors of stroke for individualized prevention measures in patients with T2DM in northern China.

METHODS

In the community-based Tianjin Chronic Disease Cohort study, 58,042 patients were enrolled between January 2014 and December 2019. We used multiple imputation (MI) to impute missing variables and univariate and multivariate Cox's proportional hazard regression to screen risk factors of stroke. Furthermore, we established and validated first-ever prediction models for stroke (Model 1 and Model 2) and death from stroke (Model 3) and evaluated their performance.

RESULTS

In the derivation and validation groups, the area under the curves (AUCs) of Models 1-3 was better at 5 years than at 8 years. The Harrell's C-index for all models was above 0.7. All models had good calibration, discrimination, and clinical net benefit. Sensitivity analysis using the MI dataset indicated that all models had good and stable prediction performance.

CONCLUSION

In this study, we developed and validated first-ever risk prediction models for stroke and death from stroke in patients with T2DM, with good discrimination and calibration observed in all models. Based on lifestyle, demographic characteristics, and laboratory examination, these models could provide multidimensional management and individualized risk assessment. However, the models developed here may only be applicable to Han Chinese.

Lysobacter enzymogenes prevents Phytophthora infection by inhibiting pathogen growth and eliciting plant immune responses

The Phytophthora pathogen causes enormous damage to important agricultural plants. This group of filamentous pathogens is phylogenetically distant from fungi, making them difficult to control by most chemical fungicides. Lysobacter enzymogenes OH11 (OH11) is a biocontrol bacterium that secretes HSAF (Heat-Stable Antifungal Factor) as a broad-spectrum antifungal weapon. Here, we showed that OH11 could also control a variety of plant Phytophthora diseases caused by three major oomycetes (P. sojae, P. capsici and P. infestans). We provided abundant evidence to prove that OH11 protected host plants from Phytophthora pathogen infection by inhibiting mycelial growth, digesting cysts, suppressing cyst germination, and eliciting plant immune responses. Interestingly, the former two processes required the presence of HSAF, while the latter two did not. This suggested that L. enzymogenes could prevent Phytophthora infection via multiple previously unknown mechanisms. Therefore, this study showed that L. enzymogenes could serve as a promising alternative resource for promoting plant resistance to multiple Phytophthora pathogens.

Cyanidin Chloride Improves LPS-Induced Depression-Like Behavior in Mice by Ameliorating Hippocampal Inflammation and Excitotoxicity

Depression is a global disease that places a significant burden on human health. Neuroinflammation and disturbance of glutamate metabolism in brain regions, such as the hippocampus, play vital roles in the development of depression. Previous studies have shown that cyanidin chloride (Cycl) has anti-inflammatory and antioxidant properties with neuroprotective effects in peripheral tissues. However, the effects of Cycl on depression and the possible mechanism by which this compound targets brain regions remain less elucidated. We investigated the role of Cycl in lipopolysaccharide (LPS)-induced depression and examined the influence of the drug on central inflammation and the expression of excitatory amino acid transporters in the hippocampus. We found that prophylactic i.p. application of Cycl at 20 or 40 mg/kg for 5 days significantly reduced the immobility time assessed by the tail suspension test (TST) and forced swim test (FST) in LPS-challenged mice, suggesting an effective antidepressant activity of the drug. Western blotting and immunofluorescence staining in the hippocampus revealed that Cycl inhibited the upregulation of proinflammatory cytokines, including TNF-α and IL-6, and suppressed the hyperactivity of microglia induced by LPS, indicating an anti-inflammatory role in the hippocampus. Moreover, treatment with Cycl also recovered the downregulated expression of glial fibrillary acidic protein (GFAP), brain-derived neurotrophic factor (BDNF), and glutamate-aspartate transporter (GLAST) and excitatory amino acid transporter 2 (EAAT2), two members in the excitatory amino acid transporter family. The role of Cycl was also verified in cultured BV2 and U251 cells. In conclusion, the present in vivo and in vitro studies demonstrate that Cycl exerts potent antidepressant action in an LPS-induced depression model and the underlying mechanism is associated with reduced hippocampal inflammation, improved neurotrophic function, and attenuated excitotoxicity induced by glutamate.

Serum fibrinogen-like protein 1 as a novel biomarker in polycystic ovary syndrome: a case-control study

PURPOSE

To investigate the relationship between fibrinogen-like protein 1 (FGL-1) concentrations and various metabolic characteristics in patients with polycystic ovary syndrome (PCOS) and explore whether FGL-1 could be a predictive biomarker for PCOS.

METHODS

This case-control study included 136 patients with PCOS and 34 normal controls recruited in the Department of Endocrinology and Metabolism, Shanghai Tenth People's Hospital between May 2017 and June 2021. Anthropometric characteristics, metabolic parameters, and reproductive hormones were collected. Serum FGL-1 measurement was conducted using enzyme-linked immunosorbent assay (ELISA) kits.

RESULTS

Serum FGL-1 concentrations were higher in patients with PCOS than in control subjects in body mass index (BMI) subgroups, insulin resistance (IR) subgroups, and hepatic function subgroups, respectively. Serum FGL-1 concentrations were significantly associated with BMI, glycosylated hemoglobin A1c (HbA1c), fasting plasma glucose (FPG), homeostasis model assessment of insulin resistance (HOMA-IR), alanine aminotransferase (ALT), aspartate aminotransferase (AST), high-density lipoprotein cholesterol (HDL-c), and serum uric acid (SUA) in all individuals. The receiver operating characteristic (ROC) curve analysis revealed that the best cutoff value for FGL-1 levels to predict PCOS was 21.02 ng/ml with a sensitivity of 74.3% and a specificity of 70.6%. Both univariate and multiple logistic regressions indicated that the odds ratio (OR) for PCOS significantly increased in the subjects with high levels of FGL-1.

CONCLUSION

In our study, FGL-1 was associated with serum aminotransferase and various metabolic indexes. Moreover, the high risk of PCOS was independently associated with the increased FGL-1 levels, which suggested that FGL-1 could be a predictive biomarker for PCOS.

Maintenance of tRNA and elongation factors supports T3SS proteins translational elongations in pathogenic bacteria during nutrient starvation

Background

Sufficient nutrition contributes to rapid translational elongation and protein synthesis in eukaryotic cells and prokaryotic bacteria. Fast synthesis and accumulation of type III secretion system (T3SS) proteins conduce to the invasion of pathogenic bacteria into the host cells. However, the translational elongation patterns of T3SS proteins in pathogenic bacteria under T3SS-inducing conditions remain unclear. Here, we report a mechanism of translational elongation of T3SS regulators, effectors and structural protein in four model pathogenic bacteria (Pseudomonas syringae, Pseudomonas aeruginosa, Xanthomonas oryzae and Ralstonia solanacearum) and a clinical isolate (Pseudomonas aeruginosa UCBPP-PA14) under nutrient-limiting conditions. We proposed a luminescence reporter system to quantitatively determine the translational elongation rates (ERs) of T3SS regulators, effectors and structural protein under different nutrient-limiting conditions and culture durations.

Results

The translational ERs of T3SS regulators, effectors and structural protein in these pathogenic bacteria were negatively regulated by the nutrient concentration and culture duration. The translational ERs in 0.5× T3SS-inducing medium were the highest of all tested media. In 1× T3SS-inducing medium, the translational ERs were highest at 0 min and then rapidly decreased. The translational ERs of T3SS regulators, effectors and structural protein were inhibited by tRNA degradation and by reduced levels of elongation factors (EFs).

Conclusions

Rapid translational ER and synthesis of T3SS protein need adequate tRNAs and EFs in nutrient-limiting conditions. Numeric presentation of T3SS translation visually indicates the invasion of bacteria and provides new insights into T3SS expression that can be applied to other pathogenic bacteria.

Quantitative structure-activity relationship modeling reveals the minimal sequence requirement and amino acid preference of sirtuin-1's deacetylation substrates in diabetes mellitus

Sirtuin 1 (SIRT1) is a nicotinamide adenine dinucleotide (NAD[Formula: see text]-dependent deacetylase involved in multiple glucose metabolism pathways and plays an important role in the pathogenesis of diabetes mellitus (DM). The enzyme specifically recognizes its deacetylation substrates' peptide segments containing a central acetyl-lysine residue as well as a number of amino acids flanking the central residue. In this study, we attempted to ascertain the minimal sequence requirement (MSR) around the central acetyl-lysine residue of SIRT1 substrate-recognition sites as well as the amino acid preference (AAP) at different residues of the MSR window through quantitative structure-activity relationship (QSAR) strategy, which would benefit our understanding of SIRT1 substrate specificity at the molecular level and is also helpful to rationally design substrate-mimicking peptidic agents against DM by competitively targeting SIRT1 active site. In this procedure, a large-scale dataset containing 6801 13-mer acetyl-lysine peptides (and their SIRT1-catalyized deacetylation activities) were compiled to train 10 QSAR regression models developed by systematic combination of machine learning methods (PLS and SVM) and five amino acids descriptors (DPPS, T-scale, MolSurf, [Formula: see text]-score, and FASGAI). The two best QSAR models (PLS+FASGAI and SVM+DPPS) were then employed to statistically examine the contribution of residue positions to the deacetylation activity of acetyl-lysine peptide substrates, revealing that the MSR can be represented by 5-mer acetyl-lysine peptides that meet a consensus motif X[Formula: see text]X[Formula: see text]X[Formula: see text](AcK)₀X[Formula: see text]. Structural analysis found that the X[Formula: see text] and (AcK)₀ residues are tightly packed against the enzyme active site and confer both stability and specificity for the enzyme-substrate complex, whereas the X[Formula: see text], X[Formula: see text] and X[Formula: see text] residues are partially exposed to solvent but can also effectively stabilize the complex system. Subsequently, a systematic deacetylation activity change profile (SDACP) was created based on QSAR modeling, from which the AAP for each residue position of MSR was depicted. With the profile, we were able to rationally design an SDACP combinatorial library with promising deacetylation activity, from which nine MSR acetyl-lysine peptides as well as two known SIRT1 acetyl-lysine peptide substrates were tested by using SIRT1 deacetylation assay. It is revealed that the designed peptides exhibit a comparable or even higher activity than the controls, although the former is considerably shorter than the latter.

ECF Sigma Factor HxuI Is Critical for In Vivo Fitness of Pseudomonas aeruginosa during Infection

The opportunistic pathogen Pseudomonas aeruginosa often adapts to its host environment and causes recurrent nosocomial infections. The extracytoplasmic function (ECF) sigma factor enables bacteria to alter their gene expression in response to host environmental stimuli. Here, we report an ECF sigma factor, HxuI, which is rapidly induced once P. aeruginosa encounters the host. Host stresses such as iron limitation, oxidative stress, low oxygen, and nitric oxide induce the expression of hxuI. By combining RNA-seq and promoter-lacZ reporter fusion analysis, we reveal that HxuI can activate the expression of diverse metabolic and virulence pathways which are critical to P. aeruginosa infections, including iron acquisition, denitrification, pyocyanin synthesis, and bacteriocin production. Most importantly, overexpression of the hxuI in the laboratory strain PAO1 promotes its colonization in both murine lung and subcutaneous infections. Together, our findings show that HxuI, a key player in host stress-response, controls the in vivo adaptability and virulence of P. aeruginosa during infection. IMPORTANCE P. aeruginosa has a strong ability to adapt to diverse environments, making it capable of causing recurrent and multisite infections in clinics. Understanding host adaptive mechanisms plays an important guiding role in the development of new anti-infective agents. Here, we demonstrate that an ECFσ factor of P. aeruginosa response to the host-inflicted stresses, which promotes the bacterial in vivo fitness and pathogenicity. Furthermore, our findings may help explain the emergence of highly transmissible strains of P. aeruginosa and the acute exacerbations during chronic infections.

Mediating Effects of Malnutrition on the Relationship between Depressive Symptoms Clusters and Muscle Function Rather than Muscle Mass in Older Hemodialysis Patients

OBJECTIVES

The purpose of this study was to investigate the association and mediation pathways among muscle mass, muscle function (muscle strength and physical performance), and malnutrition with depressive symptoms clusters in the older hemodialysis patients.

DESIGN

A multi-center cross-sectional study.

SETTING AND PARTICIPANTS

A total of 499 patients aged ≥ 60 on hemodialysis from seven facilities in Shanghai of China from 2020 to 2021.

MEASUREMENTS

Muscle mass was assessed by skeletal muscle index(SMI). Muscle strength was measured by handgrip strength, and physical performance was measured via gait speed and Timed Up and Go Test (TUGT). Nutritional status was assessed by Malnutrition Inflammation Score (MIS). Depressive symptoms were evaluated by the Patient Health Questionnaire-9 (PHQ-9). Logistic regression and mediation analyses fully adjusted for all potential confounding factors.

RESULTS

Among 499 participants (312 men, mean age 69.2±6.6 years), 108 (21.6%) had depressive symptoms. The muscle strength, physical performance and malnutrition were associated with depressive symptoms. Furthermore, malnutrition significantly mediated the association of muscle function with total, cognitive-affective symptoms. The association of the muscle function with somatic symptoms were mediated by the nutritional status. The mediated proportions of malnutrition in the relationship between physical performance and depressive symptoms clusters were stronger in somatic symptoms than in cognitive-affective symptoms.

CONCLUSIONS

Our findings suggest that muscle function rather than muscle mass may contribute substantially to the development of depressive symptoms clusters in the hemodialysis via malnutrition. The malnutrition mediated stronger in the association of muscle function with somatic symptoms. These findings may help guide clinicians to better diagnose and manage depression in the context of concomitant muscle function and malnutrition.

Unlocking the bacterial contact-dependent antibacterial activity to engineer a biocontrol alliance of two species from natural incompatibility to artificial compatibility

Plant growth-promoting rhizobacteria (PGPR) contain various biocontrol bacteria with broad-spectrum antimicrobial activity, and their single species has been extensively applied to control crop diseases. The development of complex biocontrol community by mixing two or more PGPR members together is a promising strategy to enlarge the efficacy and scope of biocontrol. However, an effective method to assess the natural compatibility of PGPR members has not yet been established to date. Here, we developed such a tool by using the bacterial contact-dependent antibacterial activity (CDAA) as a probe. We showed that the CDAA events are common in two-species interactions in the four selected representative PGPRs, represented by the incompatible interaction of Lysobacter enzymogenes strain OH11 (OH11) and Lysobacter antibioticus strain OH13 (OH13). We further showed that the CDAA between OH11 and OH13 is jointly controlled by a contact-dependent killing device, called the type IV secretion system (T4SS). By deleting the respective T4SS synthesis genes, the T4SS in both strains was co-inactivated and this step unlocked  their natural CDAA, resulting in an engineered, compatible mutant alliance that co-displayed antibacterial and antifungal activity. Therefore, this study reveals that releasing bacterial CDAA is effective to rationally engineer the biocontrol community.

Pseudomonas syringae senses polyphenols via phosphorelay crosstalk to inhibit virulence

Bacteria use a variety of mechanisms, such as two-component regulatory systems (TCSs), to rapidly sense and respond to distinct conditions and signals in their host organisms. For example, a type III secretion system (T3SS) is a key determinant of the virulence of the model plant pathogen Pseudomonas syringae and contains the TCS RhpRS as a key regulator. However, the plant-derived compound targeting RhpRS remains unknown. Here, we report that RhpRS directly interacts with polyphenols and responds by switching off P. syringae T3SS via crosstalk with alternative histidine kinases. We identify three natural polyphenols that induce the expression of the rhpRS operon in an RhpS-dependent manner. The presence of these three specific polyphenols inhibits the phosphatase activity of RhpS, thus suppressing T3SS activation in T3SS-inducing conditions. The Pro40 residue of RhpS is essential to respond to these polyphenols. In addition, three non-cognate histidine kinases cooperatively phosphorylate RhpR and antagonize the rhpS mutant phenotype. This work illustrates that plant polyphenols can directly target P. syringae RhpRS, which results in bacterial virulence being switched off via a phosphorylation-related crosstalk.

Optimized protocols for ChIP-seq and deletion mutant construction in Pseudomonas syringae

Chromatin immunoprecipitation sequencing (ChIP-seq) is an efficient technique to identify the binding sites of transcription factors (TFs) in both eukaryotes and prokaryotes. However, its application in bacteria is very heterogeneous. In this protocol, we optimized the methods of ChIP-seq that can be widely applied to plant pathogens. We used homologous recombination to construct pK18mobsacB-Psph plasmid instead of restriction site ligation and replaced transconjugation with electroporation transformation in Pseudomonas syringae deletion mutant construction, which is more efficient and faster than previous methods.

For complete details on the use and execution of this protocol, please refer to Shao et al. (2021).

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This approach can be used to construct TF-overexpressed Pseudomonas syringae strain

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Protocols for ChIP-seq library construction of Pseudomonas syringae

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A simplified procedure to construct a deletion mutant of Pseudomonas syringae

A vascularized bone graft harvested from the dorsal base of the third metacarpal bone for the treatment of scaphoid nonunion

The purpose of this retrospective study was to introduce the use of an alternative vascularized bone graft for treating scaphoid non-union. The vascularized bone graft was harvested from the dorsal base of the third metacarpal bone. From May 2014 to September 2017, 29 patients with scaphoid non-union were treated. Grip and pinch strengths were compared to the contralateral side. The patients rated wrist joint pain on a visual analogue scale. Wrist function was assessed on Mayo Wrist Score. p < 0.05 was considered statistically significant. 18 scaphoids healed at 6 weeks and the other 11 at 16 weeks. Follow-up ranged from 28 to 73 months, for a mean 48 months. At final follow-up, mean wrist flexion had improved from 65° (range, 51°-81°) preoperatively to 72° (range, 61-78°) (p > 0.05), for a contralateral value of 74° (range, 65°-86°). Mean extension had improved from 56° (range, 44°-72°) to 60° (range, 47°-76°) (p > 0.05) for a contralateral value of 66° (range, 52°-80°). Mean wrist pain improved from 4 (range, 3-8) to 2 (range, 0-4) (p < 0.05). Mean pinch strength improved from 6.4 kg (range, 5.2-7.3 kg) to 8.6 kg (6.1-9.9 kg) (p < 0.05). Mayo Wrist Score improved from 49 (range, 10-65) to 92 (range, 70-100) (p < 0.05). Transferring a vascularized bone graft harvested from the base of the third metacarpal bone was an effective alternative for the treatment of scaphoid non-union, achieving bone healing and normal wrist function without significant donor-site morbidity. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Integrated regulatory network in Pseudomonas syringae reveals dynamics of virulence

Pseudomonas syringae, a Gram-negative plant pathogen, expresses multitudinous transcriptional regulators to control the type III secretion system (T3SS) and response to diverse environmental challenges. Although the mechanisms of virulence-associated regulators of P. syringae have been studied for decades, the overall crosstalk underlying these regulators is still elusive. Here, we identify five T3SS regulators (EnvZ-OmpR, CbrAB2, PhoPQ, PilRS, and MgrA), and find that the two-component systems EnvZ-OmpR and CbrAB2 negatively regulate the T3SS. To elucidate crosstalk between 16 virulence-associated regulators in P. syringae, we map an online intricate network called "PSRnet" (Pseudomonas syringae regulatory network) by combining the differentially expressed genes (DEGs) of these 16 regulators by RNA sequencing (RNA-seq) and their binding loci by chromatin immunoprecipitation sequencing (ChIP-seq). Consequently, we identify 238 and 153 functional genes involved in the T3SS and other virulence-related pathways in KB and MM media, respectively. Our results provide insights into the mechanism of plant infections caused by P. syringae.

MiR-133 inhibits kidney injury in rats with diabetic nephropathy via MAPK/ERK pathway

OBJECTIVE

The aim of this study was to explore the effect of micro ribonucleic acid (miR)-133 on kidney injury in rats with diabetic nephropathy (DN) through the mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathway.

MATERIALS AND METHODS

The model of DN was first established in rats. Blood glucose, renal index, urinary micro-albumin (UMA), and creatinine clearance rate (CCr) were detected. Meanwhile, the protein expression levels of miR-133, kidney injury molecule-1 (KIM-1) and anti-inflammatory cytokine interleukin-8 (IL-8) were measured using Western blotting. Human renal proximal tubular epithelial cell line human kidney-2 (HK-2) was treated with high glucose to simulate DN cells in vivo. Subsequently, Western blotting was performed to detect the protein expression of KIM-1. After HK-2 cells were treated with high glucose and silenced miR-133 for 24 h, the expression changes in KIM-1 was evaluated.

RESULTS

In DN group, blood glucose, renal index, UMA, and CCr were all markedly higher than those of control group. This indicated the successful establishment of DN model in rats. The expression level of miR-133 was significantly up-regulated in DN model rats. Meanwhile, the downstream protein phosphorylated-EPK (p-EPK) showed a significantly increasing trend as well. Additionally, the protein expressions of KIM-1 and IL-8 were notably elevated. High-glucose-treated HK-2 cells showed significantly up-regulated expression levels of miR-133, KIM-1, and IL-8. After 24 h of combined treatment with high glucose and miR-133 silence, the expressions of KIM-1 and IL-8 were markedly down-regulated.

CONCLUSIONS

MiR-133 may be related to the occurrence and development of DN. The silence of miR-133 inhibits kidney injury in DN via the MAPK/ERK signaling pathway. Our findings suggest that miR-133 may be an effective target for the treatment of DN.

Signal transduction schemes in Pseudomonas syringae

To cope with their continually fluctuating surroundings, pathovars of the unicellular phytopathogen Pseudomonas syringae have developed rapid and sophisticated signalling networks to sense extracellular stimuli, which allow them to adjust their cellular composition to survive and cause diseases in host plants. Comparative genomic analyses of P. syringae strains have identified various genes that encode several classes of signalling proteins, although how this bacterium directly perceives these environmental cues remains elusive. Recent work has revealed new mechanisms of a cluster of bacterial signal transduction systems that mainly include two-component systems (such as RhpRS, GacAS, CvsRS and AauRS), extracytoplasmic function sigma factors (such as HrpL and AlgU), nucleotide-based secondary messengers, methyl-accepting chemotaxis sensor proteins and several other intracellular surveillance systems. In this review, we compile a list of the signal transduction mechanisms that P. syringae uses to monitor and respond in a timely manner to intracellular and external conditions. Further understanding of these surveillance processes will provide new perspectives from which to combat P. syringae infections.

Experimental observation of Faraday waves in soft gels

We report the experimental observation of Faraday waves on soft gels. These were obtained using agarose in a mechanically vibrated cylindrical container. Low driving frequencies induce subharmonic standing waves with spatial structure that conforms to the geometry of the container. We report the experimental observation of the first 15 resonant Faraday wave modes that can be defined by the mode number (n,ℓ) pair. We also characterize the shape of the instability tongue and show the complex dependence upon material properties can be understood as an elastocapillary effect.

Association between cigarette smoking and the susceptibility of acute myeloid leukemia: a systematic review and meta-analysis

OBJECTIVE

To elucidate the association between cigarette smoking and the susceptibility of acute myeloid leukemia (AML).

MATERIALS AND METHODS

We searched relevant articles from PubMed, Embase, and Cochrane by 1st December, 2018. This meta-analysis included 20 case-control studies, involving 7,538 AML patients and 137,924 healthy controls. Studies reported OR and 95%CI of the correlation between cigarette smoking and AML susceptibility were eligible. Subsequently, the included data were weighted by an inverse variance and analyzed using fixed-effects or random-effects model. Subgroup analysis was conducted based on ethnicities and sources of controls. Heterogeneity test was applied for the included articles. Data analyses were conducted using STATA 12.0.

RESULTS

Current smokers (OR=1.42, 95%CI= 1.28-1.57; p=0.392) and ever-smokers (OR=1.16, 95%CI=1.05-1.28; p=0.036) were associated with AML susceptibility. In the subgroup analysis by ethnicity, only current smokers (OR=1.45, 95%CI=1.29-1.63; p=0.371) and ever-smokers (OR=1.16, 95%CI=1.03-1.30; p=0.034) of the Caucasian population were associated with AML susceptibility. Stratified analysis based on SOC (source of controls) indicated increased susceptibility of AML in current smokers (OR=1.43, 95%CI=1.26-1.63; p=0.283) and ever-smokers (OR=1.20, 95%CI=1.07-1.35; p=0.078) of the population-based group. Nevertheless, only current smokers in the hospital-based group had increased susceptibility of AML (OR=1.45, 95%CI=1.19-1.76; p=0.198). The risks of AML in ever-smokers (OR=1.04, 95%CI = 0.81-1.35; p=0.054) of the hospital-based group did not remarkably changed.

CONCLUSIONS

In this meta-analysis, we confirmed the association between cigarette smoking and onset risk of AML, especially in the Caucasian population. High-quality, large-scale researches are required to be conducted in multi-center hospitals for verification.

Novel therapeutic strategies for treating Pseudomonas aeruginosa infection

INTRODUCTION

Persistent infections caused by the superbug Pseudomonas aeruginosa and its resistance to multiple antimicrobial agents are huge threats to patients with cystic fibrosis as well as those with compromised immune systems. Multidrug-resistant P. aeruginosa has posed a major challenge to conventional antibiotics and therapeutic approaches, which show limited efficacy and cause serious side effects. The public demand for new antibiotics is enormous; yet, drug development pipelines have started to run dry with limited targets available for inventing new antibacterial drugs. Consequently, it is important to uncover potential therapeutic targets.

AREAS COVERED

The authors review the current state of drug development strategies that are promising in terms of the development of novel and potent drugs to treat P. aeruginosa infection.

EXPERT OPINION

The prevention of P. aeruginosa infection is increasingly challenging. Furthermore, targeting key virulence regulators has great potential for developing novel anti-P. aeruginosa drugs. Additional promising strategies include bacteriophage therapy, immunotherapies, and antimicrobial peptides. Additionally, the authors believe that in the coming years, the overall network of molecular regulatory mechanism of P. aeruginosa virulence will be fully elucidated, which will provide more novel and promising drug targets for treating P. aeruginosa infections.

Detection of the mesenchymal-to-epithelial transition of invasive non-small cell lung cancer cells by their membrane undulation spectra

A cancer cell changes its state from being epithelial- to mesenchymal-like in a dynamic manner during tumor progression. For example, it is well known that mesenchymal-to-epithelial transition (MET) is essential for cancer cells to regain the capability of seeding on and then invading secondary/tertiary regions. However, there is no fast yet reliable method for detecting this transition. Here, we showed that membrane undulation of invasive cancer cells could be used as a novel marker for MET detection, both in invasive model cell lines and repopulated circulating tumor cells (rCTCs) from non-small cell lung cancer (NSCLC) patients. Specifically, using atomic force microscopy (AFM), it was found that the surface oscillation spectra of different cancer cells, after undergoing MET, all exhibited two distinct peaks from 0.001 to 0.007 Hz that are absent in the spectra before MET. In addition, by adopting the long short-term memory (LSTM) based recurrent neural network learning algorithm, we showed that the positions of recorded membrane undulation peaks can be used to predict the occurrence of MET in invasive NSCLC cells with high accuracy (>90% for model cell lines and >80% for rCTCs when benchmarking against the conventional bio-marker vimentin). These findings demonstrate the potential of our approach in achieving rapid MET detection with a much reduced cell sample size as well as quantifying changes in the mesenchymal level of tumor cells.

[Risk factors and clinical features of hospital-associated venous thromboembolism]

Objective: To investigate the clinical features and risk factors of hospital-associated venous thromboembolism (VTE). Methods: The study enrolled acute VTE patients admitted into China-Japan Friendship Hospital from January 1, 2017 to December 31, 2017. The hospital-associated VTE (HA-VTE) group and the community-associated VTE (CA-VTE) group were classified according to whether the VTE occurred during hospitalization or within a 90-day period of admission to hospital (including inpatient with at least two days of hospital stay or a surgical procedure under general or regional anaesthesia). Differences in clinical features, risk factors, and mortality rate were compared between the two groups. Results: A total of 437 patients with acute VTE were analyzed in the study. Among them, 266 patients were HA-VTE, 171 patients were CA-VTE. Patients in the CA-VTE group were more likely to have varicose veins, sedentary, long-distance travel, and patients in the HA-VTE group were more complicated with recent surgery (<1 month), bed rest, active malignant tumor, acute infections, acute cerebral infarction, fracture, central venous catheter (P<0.05). The CA-VTE group had more clinical symptoms such as lower extremity pain, dyspnea, chest pain and chest tightness (P<0.05). HA-VTE patients had less clinical symptoms but were more severe than the CA-VTE patients, with more sudden deaths (0 vs 3.4%, P=0.035). Among HA-VTE patients, 92.8% experienced VTE during hospitalization or within 1 month of the preceding hospital encounter, with a 13-day median time to VTE. The all-cause mortality rate was higher for HA-VTE group than CA-VTE group (8.3% vs 1.2%, P<0.001), and the in-hospital VTE was more common compared to VTE diagnosed post-discharge (12.2% vs 3.4%, P<0.001). Conclusions: More than half events of VTE are related to recent hospitalizations. HA-VTE has different risk factors from CA-VTE, combined with fewer clinical symptoms but higher all-cause mortality rate. More attention about VTE should be paid to hospitalized patients to reduce the incidence of HA-VTE events.

Envelopes in multivariate regression models with nonlinearity and heteroscedasticity

Envelopes have been proposed in recent years as a nascent methodology for sufficient dimension reduction and efficient parameter estimation in multivariate linear models. We extend the classical definition of envelopes in Cook et al. (2010) to incorporate a nonlinear conditional mean function and a heteroscedastic error. Given any two random vectors ${X}\in\mathbb{R}^{p}$ and ${Y}\in\mathbb{R}^{r}$, we propose two new model-free envelopes, called the martingale difference divergence envelope and the central mean envelope, and study their relationships to the standard envelope in the context of response reduction in multivariate linear models. The martingale difference divergence envelope effectively captures the nonlinearity in the conditional mean without imposing any parametric structure or requiring any tuning in estimation. Heteroscedasticity, or nonconstant conditional covariance of ${Y}\mid{X}$, is further detected by the central mean envelope based on a slicing scheme for the data. We reveal the nested structure of different envelopes: (i) the central mean envelope contains the martingale difference divergence envelope, with equality when ${Y}\mid{X}$ has a constant conditional covariance; and (ii) the martingale difference divergence envelope contains the standard envelope, with equality when ${Y}\mid{X}$ has a linear conditional mean. We develop an estimation procedure that first obtains the martingale difference divergence envelope and then estimates the additional envelope components in the central mean envelope. We establish consistency in envelope estimation of the martingale difference divergence envelope and central mean envelope without stringent model assumptions. Simulations and real-data analysis demonstrate the advantages of the martingale difference divergence envelope and the central mean envelope over the standard envelope in dimension reduction.

Open reduction and internal fixation obtains favorable clinical and radiographic outcomes for pediatric mandibular condylar fractures

PURPOSE

Surgery with open reduction internal fixation (ORIF) for pediatric mandibular condylar fractures (MCF) is controversial. This study aims to evaluate the clinical and radiographic outcomes of the children with MCF treated surgically with ORIF.

METHODS

This retrospective study included 9 children diagnosed with MCF and treated surgically with ORIF. Imaging examinations were performed preoperatively and postoperatively. Patients underwent follow-up clinical observations and objective measurements for over 5 years.

RESULTS

All children recovered well in facial features, facial nerve functions, occlusions, joint movements, maximal incisal opening, and midline deviation postoperatively. The temporomandibular joint (TMJ) pain and click were found in 2 of 9 (22.2%) cases 1 year after surgery and disappeared 2 years later. Mandibular retrusion was always observed in a child (11.1%) postoperatively. The condylar surface appeared unsmooth in panoramic radiographs of 2 (22.2%) cases. Objective measurements showed that a patent (11.1%) had an opening deflection and a limited laterotrusion at the return visits. SNB angles of all cases were within the normal range 5 years after the operation.

CONCLUSION

Surgery with ORIF is a relatively safe and effective method for pediatric MCF. The future growth of the mandibular condyle and the long-term TMJ function are lightly influenced in patients postoperatively.

Thumb lengthening using a three-dimensional half-ring distraction frame

The purpose of this study was to evaluate the use of a three-dimensional half-ring distraction frame for thumb phalangeal lengthening. From February 2009 to March 2015, 23 patients (23 thumbs) with thumb loss were treated with a half-ring distraction frame. Active movements of the metacarpophalangeal (MCP) joint were measured with a goniometer. These measurements were compared with the opposite hand. Differences were considered statistically significant at p<0.05. Clinical outcome was assessed based on the modified Mayo score. Bone union and good alignment were achieved in all patients. The mean distraction time was 44 days (range, 35-62 days). The mean time to union was 20 days (range, 49-86 days). The mean palmar and radial abduction of the thumb was 60° (range, 53°-65°) and 63° (range, 58°-70°), respectively; on the uninjured side, these measurements were 62° (range, 56°-65°) and 64° (range, 60°-73°), respectively (p>0.05). The mean extension-flexion arc of the MCP joint was 46° (range, 40°-50°); the measurement on the uninjured side was 48° (40°-54°) (p>0.05). The mean follow-up period was 51 months (4.25 years) (range, 48-65 months). The mean modified Mayo Score was 138 (range, 113-145). There were 19 excellent, 3 good, and 1 fair results. The half-ring distraction frame is a viable alternative for thumb lengthening as it provides stable, three-dimensional fixation, resulting in good hand function.

A method for determining surface tension, viscosity, and elasticity of gels via ultrasonic levitation of gel drops

A method for obtaining the elasticity, surface tension, and viscosity of ultrasonically levitated gel drops is presented. The drops examined were made of agarose, a hydrogel. In contrast to previous studies where fluid properties are obtained using ultrasonic levitation of a liquid drop, herein the material studied was a gel which has a significant elasticity. The work presented herein is significant in that gels are of growing importance in biomedical applications and exhibit behaviors partially determined by their elasticities and surface tensions. Obtaining surface tension for these substances is important but challenging since measuring this quantity using the standard Wilhelmy plate or DuNuoy ring methods is not possible due to breakage of the gel. The experiments were conducted on agarose gels having elasticities ranging from 12.2 to 200.3 Pa. A method is described for obtaining elasticity, surface tension, and viscosity, and the method is experimentally demonstrated for surface tension and viscosity. For the range of elasticities explored, the measured surface tension ranged from 0.1 to 0.3 N/m, and the viscosity ranged from 0.0084 to 0.0204 Pa s. The measurements of surface tension are, to the authors' knowledge, the first obtained of a gel using ultrasonic levitation.

Breastfeeding is associated with reduced risk of multiple sclerosis in males, predominantly among HLA-DRB1*15:01 carriers

BACKGROUND

Breastfeeding as an infant appears protective against later development of some autoimmune diseases, but research into its influence on multiple sclerosis (MS) risk has yielded inconclusive results.

OBJECTIVE

We investigated the possible impact of breastfeeding on MS risk.

METHODS

We used two population-based case-control studies comprising 3670 cases and 6737 matched controls. Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for association between MS and exposure to prolonged breastfeeding (4 months or longer) versus reduced breastfeeding (less than 4 months). A meta-analysis of case-control studies that assessed the impact of breastfeeding on MS risk among women and men was conducted.

RESULTS

Prolonged breastfeeding was associated with reduced MS risk among men (OR 0.7, 95% CI 0.5-0.9) but not among women (OR 0.9, 95% CI 0.8-1.1). Among men, a synergistic effect was observed between HLA-DRB1*15:01 carrier status and reduced breastfeeding.

CONCLUSIONS

Findings from the current study add to accumulating evidence that breastfeeding may be a modifiable protective factor for reducing the risk of MS in offspring. When possible, mothers should be supported to breastfeed their infants; however, the mechanism of a sex-specific biologic effect of breastfeeding on MS risk is unclear.