The genetic and molecular basis of flagellar motility has been investigated for several decades, with innovative research strategies propelling advances at a steady pace. Furthermore, as the ...phenomenon is examined in diverse bacteria, new taxon-specific regulatory and structural features are being elucidated. Motility is also a straightforward bacterial phenotype that can allow undergraduate researchers to explore the palette of molecular genetic tools available to microbiologists. This study, driven primarily by undergraduate researchers, evaluated hundreds of flagellar motility mutants in the Gram-negative plant-associated bacterium Agrobacterium fabrum. The nearly saturating screen implicates a total of 37 genes in flagellar biosynthesis, including genes of previously unknown function.
The genetic and molecular basis of flagellar motility has been investigated for several decades, with innovative research strategies propelling advances at a steady pace. Furthermore, as the ...phenomenon is examined in diverse bacteria, new taxon-specific regulatory and structural features are being elucidated. Motility is also a straightforward bacterial phenotype that can allow undergraduate researchers to explore the palette of molecular genetic tools available to microbiologists. This study, driven primarily by undergraduate researchers, evaluated hundreds of flagellar motility mutants in the Gram-negative plant-associated bacterium Agrobacterium fabrum. The nearly saturating screen implicates a total of 37 genes in flagellar biosynthesis, including genes of previously unknown function.
Stunting affects one-third of children in developing countries, but the causes remain unclear. We hypothesized that enteropathy leads to low-grade inflammation, which suppresses the growth ...hormone-IGF axis and mediates stunting.
We conducted a case-control study of 202 HIV-unexposed Zimbabwean infants who were stunted (height-for-age Z-score (HAZ) <-2; cases) or non-stunted (HAZ >-0.5; controls) at 18 months. We measured biomarkers of intestinal damage (I-FABP), inflammation (CRP, AGP, IL-6) and growth hormone-IGF axis (IGF-1, IGFBP3) in infant plasma at 6 weeks and 3, 6, 12 and 18 months, and in paired maternal-infant plasma at birth. Adjusted mean differences between biomarkers were estimated using regression models. Multivariate odds ratios of stunting were estimated by logistic regression.
At birth, cases were shorter (median (IQR) HAZ -1.00 (-1.53, -0.08) vs 0.03 (-0.57, 0.62,); P<0.001) than controls and their mothers had lower levels of IGF-1 (adjusted mean difference (95%CI) -21.4 (-39.8, -3.1) ng/mL). From 6 weeks to 12 months of age, levels of CRP and AGP were consistently higher and IGF-1 and IGFBP3 lower in cases versus controls; IGF-1 correlated inversely with inflammatory markers at all time-points. I-FABP increased between 3-12 months, indicating extensive intestinal damage during infancy, which was similar in cases and controls. In multivariate analysis, higher log10 levels of CRP (aOR 3.06 (95%CI 1.34, 6.99); P = 0.008) and AGP (aOR 7.87 (95%CI 0.74, 83.74); P = 0.087) during infancy were associated with stunting. There were no associations between levels of I-FABP, IL-6, sCD14 or EndoCAb and stunting.
Stunting began in utero and was associated with low maternal IGF-1 levels at birth. Inflammatory markers were higher in cases than controls from 6 weeks of age and were associated with lower levels of IGF-1 throughout infancy. Higher levels of CRP and AGP during infancy were associated with stunting. These findings suggest that an extensive enteropathy occurs during infancy and that low-grade chronic inflammation may impair infant growth.
BDI is the most common serious complication of laparoscopic cholecystectomy. To address this problem, a multi-society consensus conference was held to develop evidenced-based recommendations for safe ...cholecystectomy and prevention of BDI.
Literature reviews were conducted for 18 key questions across 6 broad topics around cholecystectomy directed by a steering group and subject experts from 5 surgical societies (Society of Gastrointestinal and Endoscopic Surgeons, Americas Hepato-Pancreato-Biliary Association, International Hepato-Pancreato-Biliary Association, Society for Surgery of the Alimentary Tract, and European Association for Endoscopic Surgery). Evidence-based recommendations were formulated using the grading of recommendations assessment, development, and evaluation methodology. When evidence-based recommendations could not be made, expert opinion was documented. A number of recommendations for future research were also documented. Recommendations were presented at a consensus meeting in October 2018 and were voted on by an international panel of 25 experts with greater than 80% agreement considered consensus.
Consensus was reached on 17 of 18 questions by the guideline development group and expert panel with high concordance from audience participation. Most recommendations were conditional due to low certainty of evidence. Strong recommendations were made for (1) use of intraoperative biliary imaging for uncertainty of anatomy or suspicion of biliary injury; and (2) referral of patients with confirmed or suspected BDI to an experienced surgeon/multispecialty hepatobiliary team.
These consensus recommendations should provide guidance to surgeons, training programs, hospitals, and professional societies for strategies that have the potential to reduce BDIs and positively impact patient outcomes. Development of clinical and educational research initiatives based on these recommendations may drive further improvement in the quality of surgical care for patients undergoing cholecystectomy.
Environmental enteric dysfunction (EED) may be an important modifiable cause of child stunting. We described the evolution of EED biomarkers from birth to 18 months in rural Zimbabwe and tested the ...independent and combined effects of improved water, sanitation, and hygiene (WASH), and improved infant and young child feeding (IYCF), on EED.
The Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial was a 2x2 factorial cluster-randomised trial of improved IYCF and improved WASH on child stunting and anaemia at 18 months of age. 1169 infants born to HIV-negative mothers provided plasma and faecal specimens at 1, 3, 6, 12, and 18 months of age. We measured EED biomarkers that reflect all domains of the hypothesized pathological pathway. Markers of intestinal permeability and intestinal inflammation declined over time, while markers of microbial translocation and systemic inflammation increased between 1-18 months. Markers of intestinal damage (I-FABP) and repair (REG-1β) mirrored each other, and citrulline (a marker of intestinal epithelial mass) increased from 6 months of age, suggesting dynamic epithelial turnover and regeneration in response to enteric insults. We observed few effects of IYCF and WASH on EED after adjustment for multiple comparisons. The WASH intervention decreased plasma IGF-1 at 3 months (β:0.89, 95%CI:0.81,0.98) and plasma kynurenine at 12 months (β: 0.92, 95%CI:0.87,0.97), and increased plasma IGF-1 at 18 months (β:1.15, 95%CI:1.05,1.25), but these small WASH effects did not translate into improved growth.
Overall, we observed dynamic trends in EED but few effects of IYCF or WASH on biomarkers during the first 18 months after birth, suggesting that these interventions did not impact EED. Transformative WASH interventions are required to prevent or ameliorate EED in low-income settings.
The World Health Organization (WHO) recommends systematic symptom screening for tuberculosis (TB). However, TB prevalence surveys suggest that this strategy does not identify millions of TB patients, ...globally. Undiagnosed or delayed diagnosis of TB contribute to TB transmission and exacerbate morbidity and mortality. We conducted a cluster-randomized trial of large urban and rural primary healthcare clinics in 3 provinces of South Africa to evaluate whether a novel intervention of targeted universal testing for TB (TUTT) in high-risk groups diagnosed more patients with TB per month compared to current standard of care (SoC) symptom-directed TB testing.
Sixty-two clinics were randomized; with initiation of the intervention clinics over 6 months from March 2019. The study was prematurely stopped in March 2020 due to clinics restricting access to patients, and then a week later due to the Coronavirus Disease 2019 (COVID-19) national lockdown; by then, we had accrued a similar number of TB diagnoses to that of the power estimates and permanently stopped the trial. In intervention clinics, attendees living with HIV, those self-reporting a recent close contact with TB, or a prior episode of TB were all offered a sputum test for TB, irrespective of whether they reported symptoms of TB. We analyzed data abstracted from the national public sector laboratory database using Poisson regression models and compared the mean number of TB patients diagnosed per clinic per month between the study arms. Intervention clinics diagnosed 6,777 patients with TB, 20.7 patients with TB per clinic month (95% CI 16.7, 24.8) versus 6,750, 18.8 patients with TB per clinic month (95% CI 15.3, 22.2) in control clinics during study months. A direct comparison, adjusting for province and clinic TB case volume strata, did not show a significant difference in the number of TB cases between the 2 arms, incidence rate ratio (IRR) 1.14 (95% CI 0.94, 1.38, p = 0.46). However, prespecified difference-in-differences analyses showed that while the rate of TB diagnoses in control clinics decreased over time, intervention clinics had a 17% relative increase in TB patients diagnosed per month compared to the prior year, interaction IRR 1.17 (95% CI 1.14, 1.19, p < 0.001). Trial limitations were the premature stop due to COVID-19 lockdowns and the absence of between-arm comparisons of initiation and outcomes of TB treatment in those diagnosed with TB.
Our trial suggests that the implementation of TUTT in these 3 groups at extreme risk of TB identified more TB patients than SoC and could assist in reducing undiagnosed TB patients in settings of high TB prevalence.
South African National Clinical Trials Registry DOH-27-092021-4901.
Globally, nearly 250 million children (43% of all children under 5 years of age) are at risk of compromised neurodevelopment due to poverty, stunting, and lack of stimulation. We tested the ...independent and combined effects of improved water, sanitation, and hygiene (WASH) and improved infant and young child feeding (IYCF) on early child development (ECD) among children enrolled in the Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial in rural Zimbabwe.
SHINE was a cluster-randomized community-based 2×2 factorial trial. A total of 5,280 pregnant women were enrolled from 211 clusters (defined as the catchment area of 1-4 village health workers VHWs employed by the Zimbabwean Ministry of Health and Child Care). Clusters were randomly allocated to standard of care, IYCF (20 g of small-quantity lipid-based nutrient supplement per day from age 6 to 18 months plus complementary feeding counseling), WASH (ventilated improved pit latrine, handwashing stations, chlorine, liquid soap, and play yard), and WASH + IYCF. Primary outcomes were child length-for-age Z-score and hemoglobin concentration at 18 months of age. Children who completed the 18-month visit and turned 2 years (102-112 weeks) between March 1, 2016, and April 30, 2017, were eligible for the ECD substudy. We prespecified that primary inferences would be drawn from findings of children born to HIV-negative mothers; these results are presented in this paper. A total of 1,655 HIV-unexposed children (64% of those eligible) were recruited into the ECD substudy from 206 clusters and evaluated for ECD at 2 years of age using the Malawi Developmental Assessment Tool (MDAT) to assess gross motor, fine motor, language, and social skills; the MacArthur-Bates Communicative Development Inventories (CDI) to assess vocabulary and grammar; the A-not-B test to assess object permanence; and a self-control task. Outcomes were analyzed in the intention-to-treat population. For all ECD outcomes, there was not a statistical interaction between the IYCF and WASH interventions, so we estimated the effects of the interventions by comparing the 2 IYCF groups with the 2 non-IYCF groups and the 2 WASH groups with the 2 non-WASH groups. The mean (95% CI) total MDAT score was modestly higher in the IYCF groups compared to the non-IYCF groups in unadjusted analysis: 1.35 (0.24, 2.46; p = 0.017); this difference did not persist in adjusted analysis: 0.79 (-0.22, 1.68; p = 0.057). There was no evidence of impact of the IYCF intervention on the CDI, A-not-B, or self-control tests. Among children in the WASH groups compared to those in the non-WASH groups, mean scores were not different for the MDAT, A-not-B, or self-control tests; mean CDI score was not different in unadjusted analysis (0.99 95% CI -1.18, 3.17) but was higher in children in the WASH groups in adjusted analysis (1.81 0.01, 3.61). The main limitation of the study was the specific time window for substudy recruitment, meaning not all children from the main trial were enrolled.
We found little evidence that the IYCF and WASH interventions implemented in SHINE caused clinically important improvements in child development at 2 years of age. Interventions that directly target neurodevelopment (e.g., early stimulation) or that more comprehensively address the multifactorial nature of neurodevelopment may be required to support healthy development of vulnerable children.
ClinicalTrials.gov NCT01824940.
Background To determine the role of liver resection in patients with liver and extrahepatic colorectal cancer metastases and the role of chemotherapy in patients in conjunction with liver resection. ...Methods MEDLINE and EMBASE databases were searched for articles published between 1995 and 2010, along with hand searching. Results A total of 4875 articles were identified, and 83 were retained for inclusion. Meta-analysis was not performed because of heterogeneity and poor quality of the evidence. Outcomes in patients who had liver and lung metastases, liver and portal node metastases, and liver and other extrahepatic disease were reported in 14, 10, and 14 studies, respectively. The role of perioperative chemotherapy was assessed in 30 studies, including 1 randomized controlled trial and 1 pooled analysis. Ten studies assessed the role of chemotherapy in patients with initially unresectable disease, and 5 studies assessed the need for operation after a radiologic complete response. Conclusion The review suggests that: (1) select patients with pulmonary and hepatic CRC metastases may benefit from resection; (2) perioperative chemotherapy may improve outcome in patients undergoing a liver resection; (3) patients whose CRC liver metastases are initially unresectable may benefit from chemotherapy to identify a subgroup who may benefit later from resection; (4) after radiographic complete response (RCR), lesions should be resected if possible.
Pathological vascular remodeling and excessive perivascular fibrosis are major contributors to reduced vessel compliance that exacerbates cardiovascular diseases, for instance, promoting clinically ...relevant myocardial remodeling. Inflammation plays a significant role in both pathological vascular remodeling and fibrosis. We previously demonstrated that smooth muscle cell-specific PTEN depletion promotes significant vascular fibrosis and accumulation of inflammatory cells. In the current study, we aimed to determine the beneficial role of systemic PTEN elevation on Ang II (angiotensin II)-induced vascular fibrosis and remodeling. Approach and Results: Transgenic mice carrying additional copies of the wild-type
gene (super PTEN sPTEN) and WT littermates were subjected to Ang II or saline infusion for 14 or 28 days. Compared with WT, Ang II-induced vascular fibrosis was significantly blunted in sPTEN mice, as shown by histochemical stainings and label-free second harmonic generation imaging. The protection against Ang II was recapitulated in sPTEN mice bearing WT bone marrow but not in WT mice reconstituted with sPTEN bone marrow. Ang II-induced elevation of profibrotic and proinflammatory gene expression observed in WT mice was blocked in aortic tissue of sPTEN mice. Immunofluorescent staining and flow cytometry both indicated that perivascular infiltration of T cells and macrophages was significantly inhibited in sPTEN mice. In vitro induction of PTEN expression suppressed Ang II-induced Ccl2 expression in vascular smooth muscle cells.
Systemic PTEN elevation mediates protection against Ang II-induced vascular inflammation and fibrosis predominantly through effects in resident vascular cells. Our data highly support that pharmacological upregulation of PTEN could be a novel and viable approach for the treatment of pathological vascular fibrosis.
Male circumcision significantly reduced the incidence of human immunodeficiency virus (HIV) infection among men in three clinical trials. We assessed the efficacy of male circumcision for the ...prevention of herpes simplex virus type 2 (HSV-2) and human papillomavirus (HPV) infections and syphilis in HIV-negative adolescent boys and men.
We enrolled 5534 HIV-negative, uncircumcised male subjects between the ages of 15 and 49 years in two trials of male circumcision for the prevention of HIV and other sexually transmitted infections. Of these subjects, 3393 (61.3%) were HSV-2-seronegative at enrollment. Of the seronegative subjects, 1684 had been randomly assigned to undergo immediate circumcision (intervention group) and 1709 to undergo circumcision after 24 months (control group). At baseline and at 6, 12, and 24 months, we tested subjects for HSV-2 and HIV infection and syphilis, along with performing physical examinations and conducting interviews. In addition, we evaluated a subgroup of subjects for HPV infection at baseline and at 24 months.
At 24 months, the cumulative probability of HSV-2 seroconversion was 7.8% in the intervention group and 10.3% in the control group (adjusted hazard ratio in the intervention group, 0.72; 95% confidence interval CI, 0.56 to 0.92; P=0.008). The prevalence of high-risk HPV genotypes was 18.0% in the intervention group and 27.9% in the control group (adjusted risk ratio, 0.65; 95% CI, 0.46 to 0.90; P=0.009). However, no significant difference between the two study groups was observed in the incidence of syphilis (adjusted hazard ratio, 1.10; 95% CI, 0.75 to 1.65; P=0.44).
In addition to decreasing the incidence of HIV infection, male circumcision significantly reduced the incidence of HSV-2 infection and the prevalence of HPV infection, findings that underscore the potential public health benefits of the procedure. (ClinicalTrials.gov numbers, NCT00425984 and NCT00124878.)
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