233 research outputs found
A numerical model for simulating the effect of strain rate on eutectic band thickness
Large tensile strains acting on the solidifying weld metal can cause the formation of eutectic bands along grain boundaries. These eutectic bands can lead to severe liquation in the partially melted zone of a subsequent overlapping weld. This can increase the risk of heat-affected zone liquation cracking. In this paper, we present a solidification model for modeling eutectic bands. The model is based on solute convection in grain boundary liquid films induced by tensile strains. The proposed model was used to study the influence of strain rate on the thickness of eutectic bands in Alloy 718. It was found that when the magnitude of the strain rate is 10 times larger than that of the solidification rate, the calculated eutectic band thickness is about 200 to 500% larger (depending on the solidification rate) as compared to when the strain rate is zero. In the paper, we also discuss how eutectic bands may form from hot cracks
Fast-growing pancreatic neuroendocrine carcinoma in a patient with multiple endocrine neoplasia type 1: a case report
<p>Abstract</p> <p>Introduction</p> <p>Predictive genetic screening and regular screening programs in patients with multiple endocrine neoplasia type 1 are intended to detect and treat malignant tumors at the earliest stage possible. Malignant neuroendocrine pancreatic tumors are the most frequent cause of death in these patients. However, the extent and intervals of screening in patients with multiple endocrine neoplasia type 1 are controversial as neuroendocrine tumors are usually slow growing. Here we report the case of a patient who developed a fast-growing neuroendocrine carcinoma within 15 months of a laparoscopic distal pancreatic resection.</p> <p>Case presentation</p> <p>We followed a group of 45 patients with multiple endocrine neoplasia type 1 by an annual screening program in the Department of Visceral, Thoracic, and Vascular Surgery at the University Hospital Marburg in cooperation with the Department of Radiology and the Division of Endocrinology. A man with multiple endocrine neoplasia type 1 who was diagnosed with a recurrent primary hyperparathyroidism underwent a distal pancreatic resection for a non-functional neuroendocrine tumor. In the context of our regular screening program, a large non-functional neuroendocrine tumor was diagnosed in the pancreatic head 15 months after the first pancreatic surgery. Therefore, we performed an enucleation and regional lymph node resection. At histology, the diagnosis of a neuroendocrine carcinoma with one lymph node metastasis was established. There was no evidence of recurrence 9 months after re-operation.</p> <p>Conclusion</p> <p>Fast-growing neuroendocrine tumors are rare in patients with multiple endocrine neoplasia type 1. The intervals, both postoperative and in newly diagnosed pancreatic lesions, in patients with multiple endocrine neoplasia type 1 should be reduced to 6 months to establish the early diagnosis of rapidly progressive disease in a small subset of patients.</p
The effect of hypoxia and work intensity on insulin resistance in type 2 diabetes
Context:Hypoxia and muscle contraction stimulate glucose transport in vitro. We have previously demonstrated that exercise and hypoxia have an additive effect on insulin sensitivity in type 2 diabetics.Objectives:Our objective was to examine the effects of three different hypoxic/exercise (Hy Ex) trials on glucose metabolism and insulin resistance in the 48 h after acute hypoxia in type 2 diabetics.Design, Participants, and Interventions:Eight male type 2 diabetics completed 60 min of hypoxic [mean (sem) O(2) = βΌ14.7 (0.2)%] exercise at 90% of lactate threshold [Hy Ex(60); 49 (1) W]. Patients completed an additional two hypoxic trials of equal work, lasting 40 min [Hy Ex(40); 70 (1) W] and 20 min [Hy Ex(20); 140 (12) W].Main Outcome Measures:Glucose rate of appearance and rate of disappearance were determined using the one-compartment minimal model. Homeostasis models of insulin resistance (HOMA(IR)), fasting insulin resistance index and Ξ²-cell function (HOMA(Ξ²-cell)) were calculated at 24 and 48 h after trials.Results:Peak glucose rate of appearance was highest during Hy Ex(20) [8.89 (0.56) mg/kg Β· min, P < 0.05]. HOMA(IR) and fasting insulin resistance index were improved in the 24 and 48 h after Hy Ex(60) and Hy Ex(40) (P < 0.05). HOMA(IR) decreased 24 h after Hy Ex(20) (P < 0.05) and returned to baseline values at 48 h.Conclusions:Moderate-intensity exercise in hypoxia (Hy Ex(60) and Hy Ex(40)) stimulates acute- and moderate-term improvements in insulin sensitivity that were less apparent in Hy Ex(20). Results suggest that exercise duration and not total work completed has a greater influence on acute and moderate-term glucose control in type 2 diabetics
Talking about Gypsies:Β the notion of discourse as control.
The file attached to this record is the authors final peer reviewed version. The final published version can be found on the publisher's website. http://www.informaworld.com/Gypsies and Travellers are increasingly part of a debate by politicians and the media in the U.K. This discourse is not a benign reflection of events; instead it is part of a complex mechanism of control. There is a difficult relationship between the settled and travelling communities which inhibits political discussion of a strategy for site provision. In this context, the paper examines the links between discourse and control, by paying attention to Foucaultian notions of the βgazeβ, amongst other explanations. Drawing on findings from analysis of the media, focus groups with Travellers and a case study in one local authority planning consultation exercise, the paper proposes a theoretical explanation for the link between the discourse used around Gypsies and Travellers and the control that is exercised over them, particularly in inhibiting their right to a travelling lifestyle
Limitations of Tc99m-MIBI-SPECT Imaging Scans in Persistent Primary Hyperparathyroidism
In primary hyperparathyroidism (PHPT) the predictive value of technetium 99m sestamibi single emission computed tomography (Tc99m-MIBI-SPECT) for localizing pathological parathyroid glands before a first parathyroidectomy (PTx) is 83-100%. Data are scarce in patients undergoing reoperative parathyroidectomy for persistent hyperparathyroidism. The aim of the present study was to determine the value of Tc99m-MIBI-SPECT in localizing residual hyperactive parathyroid tissue in patients with persistent primary hyperparathyroidism (PHPT) after initial excision of one or more pathological glands. We retrospectively evaluated the localizing accuracy of Tc99m-MIBI-SPECT scans in 19 consecutive patients with persistent PHPT who had a scan before reoperative parathyroidectomy. We used as controls 23 patients with sporadic PHPT who had a scan before initial surgery. In patients with persistent PHPT, Tc99m-MIBI-SPECT accurately localized a pathological parathyroid gland in 33% of cases before reoperative parathyroidectomy, compared to 61% before first PTx for sporadic PHPT. The Tc99m-MIBI-SPECT scan accurately localized intra-thyroidal glands in 2 of 7 cases and a mediastinal gland in 1 of 3 cases either before initial or reoperative parathyroidectomy. Our data suggest that the accuracy of Tc99m-MIBI-SPECT in localizing residual hyperactive glands is significantly lower before reoperative parathyroidectomy for persistent PHPT than before initial surgery for sporadic PHPT. These findings should be taken in consideration in the preoperative workup of patients with persistent primary hyperparathyroidis
Bilateral adrenocortical carcinoma in a patient with multiple endocrine neoplasia type 1 (MEN1) and a novel mutation in the MEN1 gene
The incidence of adrenal involvement in MEN1 syndrome has been reported between 9 and 45%, while the incidence of adrenocortical carcinoma (ACC) in MEN1 patients has been reported between 2.6 and 6%. In the literature data only unilateral development of ACCs in MEN1 patients has been reported. We report a 31 years-old female MEN1-patient, in whom hyperplasia of the parathyroid glands, prolactinoma, non functioning pancreatic endocrine carcinoma and functioning bilateral adrenal carcinomas were diagnosed. Interestingly, a not previously described in the literature data, novel germline mutation (p.E45V) in exon 2 of MEN1 gene, was detected. The association of exon 2 mutation of the MEN1 gene with bilateral adrenal carcinomas in MEN1 syndrome, should be further investigated
The effectiveness of proactive telephone support provided to breastfeeding mothers of preterm infants: Study protocol for a randomized controlled trial
Background: Although breast milk has numerous benefits for infants' development, with greater effects in those born preterm (at < 37 gestational weeks), mothers of preterm infants have shorter breastfeeding duration than mothers of term infants. One of the explanations proposed is the difficulties in the transition from a Neonatal Intensive Care Unit (NICU) to the home environment. A person-centred proactive telephone support intervention after discharge from NICU is expected to promote mothers' sense of trust in their own capacity and thereby facilitate breastfeeding. Methods/design: A multicentre randomized controlled trial has been designed to evaluate the effectiveness and cost-effectiveness of person-centred proactive telephone support on breastfeeding outcomes for mothers of preterm infants. Participating mothers will be randomized to either an intervention group or control group. In the intervention group person-centred proactive telephone support will be provided, in which the support team phones the mother daily for up to 14 days after hospital discharge. In the control group, mothers are offered a person-centred reactive support where mothers can phone the breastfeeding support team up to day 14 after hospital discharge. The intervention group will also be offered the same reactive telephone support as the control group. A stratified block randomization will be used; group allocation will be by high or low socioeconomic status and by NICU. Recruitment will be performed continuously until 1116 mothers (I: 558 C: 558) have been included. Primary outcome: proportion of mothers exclusively breastfeeding at eight weeks after discharge. Secondary outcomes: proportion of breastfeeding (exclusive, partial, none and method of feeding), mothers satisfaction with breastfeeding, attachment, stress and quality of life in mothers/partners at eight weeks after hospital discharge and at six months postnatal age. Data will be collected by researchers blind to group allocation for the primary outcome. A qualitative evaluation of experiences of receiving/providing the intervention will also be undertaken with mothers and staff. Discussion: This paper presents the rationale, study design and protocol for a RCT providing person-centred proactive telephone support to mothers of preterm infants. Furthermore, with a health economic evaluation, the cost-effectiveness of the intervention will be assessed
Type 2 Diabetes Is Associated with Altered NF-ΞΊB DNA Binding Activity, JNK Phosphorylation, and AMPK Phosphorylation in Skeletal Muscle after LPS
Systemic inflammation is often associated with impaired glucose metabolism. We therefore studied the activation of inflammatory pathway intermediates that interfere with glucose uptake during systemic inflammation by applying a standardised inflammatory stimulus in vivo. After ethical approval, informed consent and a thorough physical examination, 10 patients with type 2 diabetes and 10 participants with normal glucose tolerance (NGT) were given an intravenous bolus of E. coli lipopolysaccharide (LPS) of 0.3 ng/kg. Skeletal muscle biopsies and plasma were obtained at baseline and two, four and six hours after LPS. Nuclear factor (NF)-ΞΊB p65 DNA binding activity measured by ELISA, tumor necrosis factor-Ξ± and interleukin-6 mRNA expression analysed by real time reverse transcription polymerase chain reaction, and abundance of inhibitor of NF-ΞΊB (IΞΊB)Ξ±, phosphorylated c-Jun-N-terminal kinase (JNK), AMP-activated protein kinase (AMPK), and acetyl-CoA carboxylase measured by Western blotting were detected in muscle biopsy samples. Relative to subjects with NGT, patients with type 2 diabetes exhibited a more pronounced increase in NF-ΞΊB binding activity and JNK phosphorylation after LPS, whereas skeletal muscle cytokine mRNA expression did not differ significantly between groups. AMPK phosphorylation increased in volunteers with NGT, but not in those with diabetes. The present findings indicate that pathways regulating glucose uptake in skeletal muscle may be involved in the development of inflammation-associated hyperglycemia. Patients with type 2 diabetes exhibit changes in these pathways, which may ultimately render such patients more prone to develop dysregulated glucose disposal in the context of systemic inflammation
Quantitative Mass Spectrometry Analysis Using PAcIFIC for the Identification of Plasma Diagnostic Biomarkers for Abdominal Aortic Aneurysm
BACKGROUND: Abdominal aortic aneurysm (AAA) is characterized by increased aortic vessel wall diameter (>1.5 times normal) and loss of parallelism. This disease is responsible for 1-4% mortality occurring on rupture in males older than 65 years. Due to its asymptomatic nature, proteomic techniques were used to search for diagnostic biomarkers that might allow surgical intervention under nonlife threatening conditions. METHODOLOGY/PRINCIPAL FINDINGS: Pooled human plasma samples of 17 AAA and 17 control patients were depleted of the most abundant proteins and compared using a data-independent shotgun proteomic strategy, Precursor Acquisition Independent From Ion Count (PAcIFIC), combined with spectral counting and isobaric tandem mass tags. Both quantitative methods collectively identified 80 proteins as statistically differentially abundant between AAA and control patients. Among differentially abundant proteins, a subgroup of 19 was selected according to Gene Ontology classification and implication in AAA for verification by Western blot (WB) in the same 34 individual plasma samples that comprised the pools. From the 19 proteins, 12 were detected by WB. Five of them were verified to be differentially up-regulated in individual plasma of AAA patients: adiponectin, extracellular superoxide dismutase, protein AMBP, kallistatin and carboxypeptidase B2. CONCLUSIONS/SIGNIFICANCE: Plasma depletion of high abundance proteins combined with quantitative PAcIFIC analysis offered an efficient and sensitive tool for the screening of new potential biomarkers of AAA. However, WB analysis to verify the 19 PAcIFIC identified proteins of interest proved inconclusive save for five proteins. We discuss these five in terms of their potential relevance as biological markers for use in AAA screening of population at risk
Postexercise High-Fat Feeding Supresses p70S6K1 Activity in Human Skeletal Muscle.
PURPOSE: To examine the effects of reduced CHO but high post-exercise fat availability on cell signalling and expression of genes with putative roles in regulation of mitochondrial biogenesis, lipid metabolism and muscle protein synthesis (MPS). METHODS: Ten males completed a twice per day exercise model (3.5 h between sessions) comprising morning high-intensity interval (HIT) (8 x 5-min at 85% VO2peak) and afternoon steady-state (SS) running (60 min at 70% VO2peak). In a repeated measures design, runners exercised under different isoenergetic dietary conditions consisting of high CHO (HCHO: 10 CHO, 2.5 Protein and 0.8 Fat g.kg per whole trial period) or reduced CHO but high fat availability in the post-exercise recovery periods (HFAT: 2.5 CHO, 2.5 Protein and 3.5 Fat g.kg per whole trial period). RESULTS: Muscle glycogen was lower (P<0.05) at 3 (251 vs 301 mmol.kgdw) and 15 h (182 vs 312 mmol.kgdw) post-SS exercise in HFAT compared to HCHO. AMPK-Ξ±2 activity was not increased post-SS in either condition (P=0.41) though comparable increases (all P<0.05) in PGC-1Ξ±, p53, CS, Tfam, PPAR and ERRΞ± mRNA were observed in HCHO and HFAT. In contrast, PDK4 (P=0.003), CD36 (P=0.05) and CPT1 (P=0.03) mRNA were greater in HFAT in the recovery period from SS exercise compared with HCHO. p70S6K activity was higher (P=0.08) at 3 h post-SS exercise in HCHO versus HFAT (72.7 Β± 51.9 vs 44.7 Β± 27 fmol.min mg). CONCLUSION: Post-exercise high fat feeding does not augment mRNA expression of genes associated with regulatory roles in mitochondrial biogenesis though it does increase lipid gene expression. However, post-exercise p70S6K1 activity is reduced under conditions of high fat feeding thus potentially impairing skeletal muscle remodelling processes
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