Sensitivity of sediment geochemical proxies to coring location and corer type in a large lake: Implications for paleolimnological reconstruction

We compared a suite of geochemical proxies in sediment cores collected in 1982, 1988, 1991, and 2003 from sites near the depocenter of Lake Erie to evaluate the reliability of paleoenvironmental reconstructions derived from lacustrine sediments. Our proxies included the concentrations and carbon isotopic compositions of organic and inorganic carbon (TOC, CaCO 3 , δ 13 C org , and δ 13 C CaCO3 ), augmented by organic C to total N ratios (C org :N tot ), δ 15 N, and carbonate δ 18 O values (δ 18 O CaCO3 ). The three coring sites were clustered within 12 km; two types of corers—a Box corer and a Benthos gravity corer—were used for the 1991 sampling campaign. The variance of most proxies was accounted for not only by temporal environmental changes but also by coring locations and corer type, indicating that sediment spatial heterogeneity and differences in sediment recovery due to the use of different corers also played a part in determining the geochemical compositions of these cores. The TOC, δ 13 C org , and δ 13 C CaCO3 values showed decadal temporal patterns that were consistent between the multiple sampling campaigns. In contrast, the δ 15 N, C org :N tot , CaCO 3 , and δ 18 O CaCO3 exhibited across‐core differences in their temporal variations, making it difficult to extract consistent environment information from different cores. Our findings suggest that in addition to temporal environmental changes, high‐resolution paleolimnological reconstruction is sensitive to many factors that could include spatial sediment heterogeneity, discontinuous sedimentation processes, bioturbation, sediment dating uncertainty, and artifacts associated with analytical and coring procedures. Therefore, multiple‐core sampling and analysis are important in reliably reconstructing environmental changes, particularly for large, heterogeneous lacustrine basins. Key Points Geochemical proxies in five sediment cores from Lake Erie were compared Geochemical record was sensitive to coring location and corer type Multiple cores are necessary for reliable paleolimnological reconstructionPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/107562/1/ggge20455.pd

Meal-induced increases in C-reactive protein, interleukin-6 and tumour necrosis factor α are attenuated by prandial + basal insulin in patients with Type 2 diabetes

Aim To determine if a regimen with prandial+basal insulin compared with basal insulin attenuates post-meal inflammatory and glycative biomarkers in patients with Type2 diabetes. Methods This test-meal sub-study in the USA is from a previously reported clinical trial comparing the effect on glycaemic control of 24weeks of thrice-daily pre-meal insulin lispro mix50 (50% insulin lispro, 50% insulin lispro protamine suspension) or bedtime insulin glargine, both plus metformin. In the sub-study, glucose, insulin, triglycerides, high-sensitivity C-reactive protein, tumour necrosis factor alpha , interleukin-6, methylglyoxal and 3-deoxyglucosone were measured during the post-meal period of a mixed-meal breakfast at the final visit. Prandial+basal (n=25) and basal (n=21) insulin were administered at the same times as during the previous 24weeks. Results Post-meal, the prandial+basal insulin group had significantly higher insulin, lower glucose and triglycerides, as well as lower high-sensitivity C-reactive protein, tumour necrosis factor alpha and interleukin-6, than the basal insulin group. Glucose incremental area under the concentration curve significantly correlated with high-sensitivity C-reactive protein, tumour necrosis factor alpha , interleukin-6, methylglyoxal and 3-deoxyglucosone incremental area under the concentration curve. Insulin incremental area under the concentration curve correlated inversely with high-sensitivity C-reactive protein and tumour necrosis factor alpha incremental area under the concentration curve. However, after adjusting for glucose incremental area under the concentration curve, these inverse correlations were no longer significant. Triglyceride incremental area under the concentration curve was not correlated with any biomarker incremental area under the concentration curve. Conclusions Controlling post-meal hyperglycaemia with prandial+basal insulin in patients with Type2 diabetes attenuates meal-induced increases in high-sensitivity C-reactive protein, interleukin-6 and tumour necrosis factor alpha compared with basal insulin. The rise in post-meal glucose, but not triglycerides, significantly correlated with the rise in post-meal inflammatory and glycative biomarkers.Original Abstract: Diabet. Med. 28, 1088-1095 (2011

Association of Chartered Physiotherapists in Respiratory Care scoping review: Post-operative physiotherapy management in upper gastrointestinal (GI) surgery

Objective This scoping review will identify and synthesise the available evidence for post-operative physiotherapy following upper GI surgery, in order to identify gaps in the literature, inform evidence-based practice and contribute towards guidelines and/or policy development. Introduction Physiotherapy management following thoracic, cardiac and upper gastrointestinal surgery has been identified as one of the five key priorities for review by the Association of Chartered Physiotherapists in Respiratory Care (ACPRC) editorial board. Previously, systematic reviews have been published with a focus on one type of physiotherapy treatment. The aim of this scoping review was to identify all types of post-operative physiotherapy following upper GI surgery research to provide a comprehensive review of available evidence

PAR2 (protease-activated receptor 2) Deficiency Attenuates Atherosclerosis in Mice

Objective-PAR2 (protease-activated receptor 2)-dependent signaling results in augmented inflammation and has been implicated in the pathogenesis of several autoimmune conditions. The objective of this study was to determine the effect of PAR2 deficiency on the development of atherosclerosis. Approach and Resutle-PAR2 mRNA and protein expression is increased in human carotid artery and mouse aortic arch atheroma versus control carotid and aortic arch arteries, respectively. To determine the effect of PAR2 deficiency on atherosclerosis, male and female low-density lipoprotein receptor-deficient (Ldlr-/-) mice (8-12 weeks old) that were Par2+/+ or Par2-/- were fed a fat-and cholesterol-enriched diet for 12 or 24 weeks. PAR2 deficiency attenuated atherosclerosis in the aortic sinus and aortic root after 12 and 24 weeks. PAR2 deficiency did not alter total plasma cholesterol concentrations or lipoprotein distributions. Bone marrow transplantation showed that PAR2 on nonhematopoietic cells contributed to atherosclerosis. PAR2 deficiency significantly attenuated levels of the chemokines Ccl2 and Cxcl1 in the circulation and macrophage content in atherosclerotic lesions. Mechanistic studies using isolated primary vascular smooth muscle cells showed that PAR2 deficiency is associated with reduced Ccl2 and Cxcl1 mRNA expression and protein release into the supernatant resulting in less monocyte migration.Conclusion-Our results indicate that PAR2 deficiency is associated with attenuation of atherosclerosis and may reduce lesion progression by blunting Ccl2-and Cxcl1-induced monocyte infiltration

Base-pair neutral homozygotes can be discriminated by calibrated high-resolution melting of small amplicons

Genotyping by high-resolution melting analysis of small amplicons is homogeneous and simple. However, this approach can be limited by physical and chemical components of the system that contribute to intersample melting variation. It is challenging for this method to distinguish homozygous G::C from C::G or A::T from T::A base-pair neutral variants, which comprise ∼16% of all human single nucleotide polymorphisms (SNPs). We used internal oligonucleotide calibrators and custom analysis software to improve small amplicon (42–86 bp) genotyping on the LightScanner®. Three G/C (PAH c.1155C>G, CHK2 c.1-3850G>C and candidate gene BX647987 c.261+22,290C>G) and three T/A (CPS1 c.3405-29A>T, OTC c.299-8T>A and MSH2 c.1511-9A>T) human single nucleotide variants were analyzed. Calibration improved homozygote genotyping accuracy from 91.7 to 99.7% across 1105 amplicons from 141 samples for five of the six targets. The average Tm standard deviations of these targets decreased from 0.067°C before calibration to 0.022°C after calibration. We were unable to generate a small amplicon that could discriminate the BX647987 c.261+22,290C>G (rs1869458) SNP, despite reducing standard deviations from 0.086°C to 0.032°C. Two of the sites contained symmetric nearest neighbors adjacent to the SNPs. Unexpectedly, we were able to distinguish these homozygotes by Tm even though current nearest neighbor models predict that the two homozygous alleles would be identical

Central African Hunters Exposed to Simian Immunodeficiency Virus

HIV-seronegative Cameroonians with exposure to nonhuman primates were tested for simian immunodeficiency virus (SIV) infection. Seroreactivity was correlated with exposure risk (p<0.001). One person had strong humoral and weak cellular immune reactivity to SIVcol peptides. Humans are exposed to and possibly infected with SIV, which has major public health implications

Intensive versus conventional glycaemic control for treating diabetic foot ulcers

This is the protocol for a review and there is no abstract. The objectives are as follows: To assess the effects of intensive glycaemic control compared to conventional control on the outcome of foot ulcers in patients with type 1 and type 2 diabetes

The Role of Nitric Oxide in Mycobacterial Infections

Although tuberculosis poses a significant health threat to the global population, it is a challenge to develop new and effective therapeutic strategies. Nitric oxide (NO) and inducible NO synthase (iNOS) are important in innate immune responses to various intracellular bacterial infections, including mycobacterial infections. It is generally recognized that reactive nitrogen intermediates play an effective role in host defense mechanisms against tuberculosis. In a murine model of tuberculosis, NO plays a crucial role in antimycobacterial activity; however, it is controversial whether NO is critically involved in host defense against Mycobacterium tuberculosis in humans. Here, we review the roles of NO in host defense against murine and human tuberculosis. We also discuss the specific roles of NO in the central nervous system and lung epithelial cells during mycobacterial infection. A greater understanding of these defense mechanisms in human tuberculosis will aid in the development of new strategies for the treatment of disease