59 research outputs found
The Impact of the COVID-19 Pandemic on the Career Preparedness of Chemistry Graduates
Recent research has established that the COVID-19 pandemic has resulted in a shift in University student expectations of their graduate prospects due to unavoidable changes in their learning experiences during the pandemic, as well as the decrease in number of available jobs because of the economic impact of measures put in place to reduce COVID-19 transmission. This study used a survey to investigate: (a) the impact of the pandemic on student destinations six months after graduation and (b) the variations in perceptions of personal level of career preparedness between pre-pandemic graduates and graduates at different stages of the pandemic (i.e. the graduating classes of 2020 and 2021). 40 University of Leicester chemistry graduates engaged with the survey and analysis of the data revealed a non-statistically significant negative impact on employment six-months after graduation that appears to only affect graduates in 2020. The data also suggests that increased experience of the blended learning approaches adopted at the University of Leicester during the pandemic studies may better prepare graduates for remote working practices (e.g. using remote video conferencing software)
Ethnic differences in beta cell function occur independently of insulin sensitivity and pancreatic fat in black and white men
Introduction It is increasingly recognized that type 2 diabetes (T2D) is a heterogenous disease with ethnic variations. Differences in insulin secretion, insulin resistance and ectopic fat are thought to contribute to these variations. Therefore, we aimed to compare postprandial insulin secretion and the relationships between insulin secretion, insulin sensitivity and pancreatic fat in men of black West African (BA) and white European (WE) ancestry. Research design and methods A cross-sectional, observational study in which 23 WE and 23 BA men with normal glucose tolerance, matched for body mass index, underwent a mixed meal tolerance test with C peptide modeling to measure beta cell insulin secretion, an MRI to quantify intrapancreatic lipid (IPL), and a hyperinsulinemic-euglycemic clamp to measure whole-body insulin sensitivity. Results Postprandial insulin secretion was lower in BA versus WE men following adjustment for insulin sensitivity (estimated marginal means, BA vs WE: 40.5 (95% CI 31.8 to 49.2) × 10 3 vs 56.4 (95% CI 48.9 to 63.8) × 10 3 pmol/m 2 body surface area × 180 min, p=0.008). There was a significantly different relationship by ethnicity between IPL and insulin secretion, with a stronger relationship in WE than in BA (r=0.59 vs r=0.39, interaction p=0.036); however, IPL was not a predictor of insulin secretion in either ethnic group following adjustment for insulin sensitivity. Conclusions Ethnicity is an independent determinant of beta cell function in black and white men. In response to a meal, healthy BA men exhibit lower insulin secretion compared with their WE counterparts for their given insulin sensitivity. Ethnic differences in beta cell function may contribute to the greater risk of T2D in populations of African ancestry
Exploring the determinants of ethnic differences in insulin clearance between men of Black African and White European ethnicity
Aim: People of Black African ancestry, who are known to be at disproportionately high risk of type 2 diabetes (T2D), typically exhibit lower hepatic insulin clearance compared with White Europeans. However, the mechanisms underlying this metabolic characteristic are poorly understood. We explored whether low insulin clearance in Black African (BA) men could be explained by insulin resistance, subclinical inflammation or adiponectin concentrations. Methods: BA and White European (WE) men, categorised as either normal glucose tolerant (NGT) or with T2D, were recruited to undergo the following: a mixed meal tolerance test with C-peptide modelling to determine endogenous insulin clearance; fasting serum adiponectin and cytokine profiles; a hyperinsulinaemic–euglycaemic clamp to measure whole-body insulin sensitivity; and magnetic resonance imaging to quantify visceral adipose tissue. Results: Forty BA (20 NGT and 20 T2D) and 41 WE (23 NGT and 18 T2D) men were studied. BA men had significantly lower insulin clearance (P = 0.011) and lower plasma adiponectin (P = 0.031) compared with WE men. In multiple regression analysis, ethnicity, insulin sensitivity and plasma adiponectin were independent predictors of insulin clearance, while age, visceral adiposity and tumour necrosis factor alpha (TNF-α) did not significantly contribute to the variation. Conclusion: These data suggest that adiponectin may play a direct role in the upregulation of insulin clearance beyond its insulin-sensitising properties
Insulin clearance as the major player in the hyperinsulinaemia of black African men without diabetes
Aim: To investigate relationships between insulin clearance, insulin secretion, hepatic fat accumulation and insulin sensitivity in black African (BA) and white European (WE) men. Methods: Twenty-three BA and twenty-three WE men with normal glucose tolerance, matched for age and body mass index, underwent a hyperglycaemic clamp to measure insulin secretion and clearance, hyperinsulinaemic-euglycaemic clamp with stable glucose isotope infusion to measure whole-body and hepatic-specific insulin sensitivity, and magnetic resonance imaging to quantify intrahepatic lipid (IHL). Results: BA men had higher glucose-stimulated peripheral insulin levels (48.1 [35.5, 65.2] × 103 vs. 29.9 [23.3, 38.4] × 103 pmol L−1 × min, P =.017) and lower endogeneous insulin clearance (771.6 [227.8] vs. 1381 [534.3] mL m−2 body surface area min −1, P <.001) compared with WE men. There were no ethnic differences in beta-cell insulin secretion or beta-cell responsivity to glucose, even after adjustment for prevailing insulin sensitivity. In WE men, endogenous insulin clearance was correlated with whole-body insulin sensitivity (r = 0.691, P =.001) and inversely correlated with IHL (r = −0.674, P =.001). These associations were not found in BA men. Conclusions: While normally glucose-tolerant BA men have similar insulin secretory responses to their WE counterparts, they have markedly lower insulin clearance, which does not appear to be explained by either insulin resistance or hepatic fat accumulation. Low insulin clearance may be the primary mechanism of hyperinsulinaemia in populations of African origin
Postoperative complications and waiting time for surgical intervention after radiologically guided drainage of intra-abdominal abscess in patients with Crohn's disease
In patients with active Crohn's disease (CD), treatment of intra-abdominal abscess usually comprises antibiotics and radiologically guided percutaneous drainage (PD) preceding surgery. The aim of this study was to investigate the risk of postoperative complications and identify the optimal time interval for surgical intervention after PD
Watchful Waiting After Radiological Guided Drainage of Intra-abdominal Abscess in Patients With Crohn's Disease Might Be Associated With Increased Rates of Stoma Construction
Background: Management of spontaneous intra-abdominal abscess (IAA) in patients with Crohn's disease (CD) with radiologically guided percutaneous drainage (PD) was debated. Methods: This is a secondary analysis from a multicenter, retrospective cohort study of all the patients with CD who underwent PD followed by surgery at 19 international tertiary centers. Results: Seventeen patients (4.8%) who did not undergo surgery after PD were compared to those who had PD followed by surgical intervention 335/352 (95.2%). Patients who had PD without surgery were those with longer disease duration, more frequently had previous surgery for CD (laparotomies/laparoscopies), enteric fistula, on steroid treatment before and continue to have it after PD. Patients who had PD without subsequent surgical resection had a higher risk of stoma construction at later stages 8/17 (47.1%) versus 90/326 (27.6%) (P < .01). Patients with PD with no subsequent surgery had numerically higher rates of abscess recurrence 5/17 (29.4%) compared to those who had PD followed by surgery 45/335 (13.4%) the difference was not statistically significant (P = .07). Conclusions: Even with the low number of patients enrolled in this study who had PD of IAA without subsequent surgery, the findings indicate a markedly worse prognosis in terms of recurrence, length of stay, readmission, and stoma construction. Watchful waiting after PD to treat patients with spontaneous IAA might be indicated in selected patients with poor health status or poor prognostic factors
Cyr61/CCN1 Is Regulated by Wnt/β-Catenin Signaling and Plays an Important Role in the Progression of Hepatocellular Carcinoma
Abnormal activation of the canonical Wnt signaling pathway has been implicated in carcinogenesis. Transcription of Wnt target genes is regulated by nuclear β-catenin, whose over-expression is observed in Hepatocellular Carcinoma (HCC) tissue. Cyr61, a member of the CCN complex family of multifunctional proteins, is also found over-expressed in many types of tumor and plays dramatically different roles in tumorigenesis. In this study, we investigated the relationship between Cyr61 and β-catenin in HCC. We found that while Cyr61 protein was not expressed at a detectable level in the liver tissue of healthy individuals, its expression level was elevated in the HCC and HCC adjacent tissues and was markedly increased in cancer-adjacent hepatic cirrhosis tissue. Over-expression of Cyr61 was positively correlated with increased levels of β-catenin in human HCC samples. Activation of β-catenin signaling elevated the mRNA level of Cyr61 in HepG2 cells, while inhibition of β-catenin signaling reduced both mRNA and protein levels of Cyr61. We identified two TCF4-binding elements in the promoter region of human Cyr61 gene and demonstrated that β-catenin/TCF4 complex specifically bound to the Cyr61 promoter in vivo and directly regulated its promoter activity. Furthermore, we found that over-expression of Cyr61 in HepG2 cells promoted the progression of HCC xenografts in SCID mice. These findings indicate that Cyr61 is a direct target of β-catenin signaling in HCC and may play an important role in the progression of HCC
Simvastatin Sodium Salt and Fluvastatin Interact with Human Gap Junction Gamma-3 Protein
Finding pleiomorphic targets for drugs allows new indications or warnings for treatment to be identified. As test of concept, we applied a new chemical genomics approach to uncover additional targets for the widely prescribed lipid-lowering pro-drug simvastatin. We used mRNA extracted from internal mammary artery from patients undergoing coronary artery surgery to prepare a viral cardiovascular protein library, using T7 bacteriophage. We then studied interactions of clones of the bacteriophage, each expressing a different cardiovascular polypeptide, with surface-bound simvastatin in 96-well plates. To maximise likelihood of identifying meaningful interactions between simvastatin and vascular peptides, we used a validated photo-immobilisation method to apply a series of different chemical linkers to bind simvastatin so as to present multiple orientations of its constituent components to potential targets. Three rounds of biopanning identified consistent interaction with the clone expressing part of the gene GJC3, which maps to Homo sapiens chromosome 7, and codes for gap junction gamma-3 protein, also known as connexin 30.2/31.3 (mouse connexin Cx29). Further analysis indicated the binding site to be for the N-terminal domain putatively ‘regulating’ connexin hemichannel and gap junction pores. Using immunohistochemistry we found connexin 30.2/31.3 to be present in samples of artery similar to those used to prepare the bacteriophage library. Surface plasmon resonance revealed that a 25 amino acid synthetic peptide representing the discovered N-terminus did not interact with simvastatin lactone, but did bind to the hydrolysed HMG CoA inhibitor, simvastatin acid. This interaction was also seen for fluvastatin. The gap junction blockers carbenoxolone and flufenamic acid also interacted with the same peptide providing insight into potential site of binding. These findings raise key questions about the functional significance of GJC3 transcripts in the vasculature and other tissues, and this connexin’s role in therapeutic and adverse effects of statins in a range of disease states
Evaluation of appendicitis risk prediction models in adults with suspected appendicitis
Background
Appendicitis is the most common general surgical emergency worldwide, but its diagnosis remains challenging. The aim of this study was to determine whether existing risk prediction models can reliably identify patients presenting to hospital in the UK with acute right iliac fossa (RIF) pain who are at low risk of appendicitis.
Methods
A systematic search was completed to identify all existing appendicitis risk prediction models. Models were validated using UK data from an international prospective cohort study that captured consecutive patients aged 16–45 years presenting to hospital with acute RIF in March to June 2017. The main outcome was best achievable model specificity (proportion of patients who did not have appendicitis correctly classified as low risk) whilst maintaining a failure rate below 5 per cent (proportion of patients identified as low risk who actually had appendicitis).
Results
Some 5345 patients across 154 UK hospitals were identified, of which two‐thirds (3613 of 5345, 67·6 per cent) were women. Women were more than twice as likely to undergo surgery with removal of a histologically normal appendix (272 of 964, 28·2 per cent) than men (120 of 993, 12·1 per cent) (relative risk 2·33, 95 per cent c.i. 1·92 to 2·84; P < 0·001). Of 15 validated risk prediction models, the Adult Appendicitis Score performed best (cut‐off score 8 or less, specificity 63·1 per cent, failure rate 3·7 per cent). The Appendicitis Inflammatory Response Score performed best for men (cut‐off score 2 or less, specificity 24·7 per cent, failure rate 2·4 per cent).
Conclusion
Women in the UK had a disproportionate risk of admission without surgical intervention and had high rates of normal appendicectomy. Risk prediction models to support shared decision‐making by identifying adults in the UK at low risk of appendicitis were identified
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