Comparing the reaction profiles of single iron catalytic sites in enzymes and in reticular frameworks for methane-to-methanol oxidation

The design of synthetic inorganic catalysts mimicking the first coordination spheres of enzymatic cofactors often results in lower yields and selectivity than their biological counterparts. In this study, we exploit Kohn-Sham density functional methods to compare the reaction profiles of four single iron-based catalysts for the direct oxidation of methane to methanol: two biomimetic models based on two enzymes (cytochrome P450 and taurine dioxygenase [TauD]) and two synthetic reticular frameworks (iron-BEA zeolite and tri-iron oxo-center-based metal-organic framework). Both the biomimetic and inorganic catalysts show almost zero selectivity toward methanol for methane conversions >1% at ambient temperature. This study highlights that iron's first coordination shell can influence selectivity toward methanol but to a limited extent. In the absence of methanol protection strategies, high selectivity can be reached only by mimicking the reaction microenvironment of enzymes beyond the first coordination shell of iron

Rural, urban and migrant differences in noncommunicable disease risk-factors in middle income countries: a cross-sectional study of WHO-SAGE Data

Understanding how urbanisation and rural-urban migration influence risk-factors for non-communicable disease (NCD) is crucial for developing effective preventative strategies globally. This study compares NCD risk-factor prevalence in urban, rural and migrant populations in China, Ghana, India, Mexico, Russia and South Africa.Study participants were 39,436 adults within the WHO Study on global AGEing and adult health (SAGE), surveyed 2007-2010. Risk ratios (RR) for each risk-factor were calculated using logistic regression in country-specific and all country pooled analyses, adjusted for age, sex and survey design. Fully adjusted models included income quintile, marital status and education.Regular alcohol consumption was lower in migrant and urban groups than in rural groups (pooled RR and 95%CI: 0.47 (0.31-0.68); 0.58, (0.46-0.72), respectively). Occupational physical activity was lower (0.86 (0.72-0.98); 0.76 (0.65-0.85)) while active travel and recreational physical activity were higher (pooled RRs for urban groups; 1.05 (1.00-1.09), 2.36 (1.95-2.83), respectively; for migrant groups: 1.07 (1.0 -1.12), 1.71 (1.11-2.53), respectively). Overweight, raised waist circumference and diagnosed diabetes were higher in urban groups (1.19 (1.04-1.35), 1.24 (1.07-1.42), 1.69 (1.15-2.47), respectively). Exceptions to these trends exist: obesity indicators were higher in rural Russia; active travel was lower in urban groups in Ghana and India; and in South Africa, urban groups had the highest alcohol consumption.Migrants and urban dwellers had similar NCD risk-factor profiles. These were not consistently worse than those seen in rural dwellers. The variable impact of urbanisation on NCD risk must be considered in the design and evaluation of strategies to reduce the growing burden of NCDs globally

Perioperative outcomes and adverse events of robotic colorectal resections for inflammatory bowel disease: a systematic literature review

The purpose of this study was to assess outcome measures and cost-effectiveness of robotic colorectal resections in adult patients with inflammatory bowel disease. The Cochrane Library, PubMed/Medline and Embase databases were reviewed, using the text “robotic(s)” AND (“inflammatory bowel disease” OR “Crohn’s” OR “Ulcerative Colitis”). Two investigators screened abstracts for eligibility. All English language full-text articles were reviewed for specified outcomes. Data were pre - sented in a summarised and aggregate form, since the lack of higher-level evidence studies precluded meta-analysis. Primary outcomes included mortality and postoperative complications. Secondary outcomes included readmission rate, length of stay, conversion rate, procedure time, estimated blood loss and functional outcome. The tertiary outcome was cost-effectiveness. Eight studies (3 case-matched observational studies, 4 case series and 1 case report) met the inclusion criteria. There was no reported mortality. Overall, complications occurred in 81 patients (54%) including 30 (20%) Clavien-Dindo III–IV complica - tions. Mean length of stay was 8.6 days. Eleven cases (7.3%) were converted to open. The mean robotic operating time was 99 min out of a mean total operating time of 298.6 min. Thirty-two patients (24.7%) were readmitted. Functional outcomes were comparable among robotic, laparoscopic and open approaches. Case-matched observational studies comparing robotic to laparoscopic surgery revealed a significantly longer procedure time; however, conversion, complication, length of stay and readmission rates were similar. The case-matched observational study comparing robotic to open surgery also revealed a longer procedure time and a higher readmission rate; postoperative complication rates and length of stay were similar. No studies compared cost-effectiveness between robotic and traditional approaches. Although robotic resections for inflamma - tory bowel disease are technically feasible, outcomes must be interpreted with caution due to low-quality studies

Influence of First and Second Coordination Environment on Structural Fe(II) Sites in MIL-101 for C–H Bond Activation in Methane

Divalent iron sites in tri-iron oxo-centered metal nodes in metal–organic frameworks (MOFs) catalyze light alkane oxidation. The first two steps of the reaction sequence, which are also the most en..

Comments on the article “Clinical and radiological outcomes of fixed- versus mobile-bearing total knee replacement: a meta-analysis”

Diagnosis and treatment of bone and soft tissue tumour

Large parathyroid adenomas: Potential mechanisms to reconcile adenoma size and disease phenotype

Parathyroid adenomas weighing more than 3.5 g are reported variously as atypical , large or giant parathyroid adenomas. All such adenomas are rare variants accounting for no more than 1.5% of all parathyroid adenomas. Large parathyroid adenomas are often associated with more severe form of the disease, including osteitis fibrosa cystica (OFC) and share many biochemical, histological, and molecular features of both benign and malignant parathyroid neoplasms, and are considered a distinct clinical entity. However, the pathogenesis of oversized parathyroid adenomas and the often-associated skeletal phenotype remains unclear. We present 5 cases of primary hyperparathyroidism (PHPT) with OFC, an uncommon manifestation of contemporary PHPT, associated with larger parathyroid adenomas, seen in the Bone and Mineral Disorders Clinic of the Henry Ford Health in the last 30 years to illustrate the critical role of vitamin D nutrition in the pathogenesis of both the OFC and adenoma size. The estimated prevalence of OFC was very low 0.2%, 5 of the \u3e3000 surgically confirmed cases of PHPT seen during this time. The mean ± SD values were: age: 36.8 ± 22.1 years (4 of the 510 years of follow-up. Because OFC is a very rare in the West, but very common areas of endemic vitamin D deficiency, we also examined the relationship between vitamin D nutrition, as assessed by serum 25-hydroxyvitamin D level, and parathyroid adenoma weight as well as prevalence of OFC in two large secularly diverse cohorts of patients with PHPT (Detroit, USA and Chandigarh, India). Based on this relationship and the relative prevalence of OFC in these two large cohorts, we propose that vitamin D nutrition (and perhaps calcium nutrition) best explains both the adenoma size and prevalence of OFC

Estrogen-mediated gut microbiome alterations influence sexual dimorphism in metabolic syndrome in mice

peer-reviewedBackground Understanding the mechanism of the sexual dimorphism in susceptibility to obesity and metabolic syndrome (MS) is important for the development of effective interventions for MS. Results Here we show that gut microbiome mediates the preventive effect of estrogen (17β-estradiol) on metabolic endotoxemia (ME) and low-grade chronic inflammation (LGCI), the underlying causes of MS and chronic diseases. The characteristic profiles of gut microbiome observed in female and 17β-estradiol-treated male and ovariectomized mice, such as decreased Proteobacteria and lipopolysaccharide biosynthesis, were associated with a lower susceptibility to ME, LGCI, and MS in these animals. Interestingly, fecal microbiota-transplant from male mice transferred the MS phenotype to female mice, while antibiotic treatment eliminated the sexual dimorphism in MS, suggesting a causative role of the gut microbiome in this condition. Moreover, estrogenic compounds such as isoflavones exerted microbiome-modulating effects similar to those of 17β-estradiol and reversed symptoms of MS in the male mice. Finally, both expression and activity of intestinal alkaline phosphatase (IAP), a gut microbiota-modifying non-classical anti-microbial peptide, were upregulated by 17β-estradiol and isoflavones, whereas inhibition of IAP induced ME and LGCI in female mice, indicating a critical role of IAP in mediating the effects of estrogen on these parameters. Conclusions In summary, we have identified a previously uncharacterized microbiome-based mechanism that sheds light upon sexual dimorphism in the incidence of MS and that suggests novel therapeutic targets and strategies for the management of obesity and MS in males and postmenopausal women