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A brief exposure to moderate passive smoke increases metabolism and thyroid hormone secretion.CONTEXT: Active smoking influences normal metabolic status and thyroid function. OBJECTIVE: The objective was to assess experimentally the effects of 1 h of moderate passive smoking in a controlled simulated bar/restaurant environment on the metabolism and thyroid hormone levels in healthy nonsmokers. PARTICIPANTS: Eighteen (nine females, nine males) healthy individuals (mean +/- sd: age, 25.3 +/- 3.1 yr; height, 174.0 +/- 10.1 cm; weight, 65.2 +/- 13.7 kg) participated in the study. DESIGN: In repeated-measures randomized blocks, participants visited the laboratory on 2 consecutive days. In the experimental condition, they were exposed to 1 h of moderate passive smoking at a carbon monoxide concentration of 23 +/- 1 ppm in an environmental chamber, whereas in the control condition participants remained in the same chamber for 1 h breathing normal atmospheric air. MAIN OUTCOME MEASURES: In both conditions, cotinine serum and urine levels, resting energy expenditure (REE), as well as concentration of T3, free T4, and TSH were assessed before participants entered the chamber and immediately after their exit. Heart rate and blood pressure were tested in 10-min intervals during all REE assessments. RESULTS: The mean +/- sd difference of serum and urine cotinine levels (-0.27 +/- 3.94 vs. 14.01 +/- 6.54 and 0.05 +/- 2.07 vs. 7.23 +/- 3.75, respectively), REE (6.73 +/- 98.06 vs. 80.58 +/- 120.91) as well as T3 and free T4 (0.05 +/- 0.11 vs. 0.13 +/- 0.12 and 0.02 +/- 0.15 vs. 0.22 +/- 0.20) were increased in the experimental compared with the control condition at baseline and follow-up (P < 0.05). No statistically significant variation was observed in the mean difference of the remaining parameters (P > 0.05). Serum and urine cotinine values were linearly associated with REE (P < 0.05). CONCLUSION: One hour of passive smoking at bar/restaurant levels is accompanied by significant increases in metabolism and thyroid hormone levels.
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A comparison of two stretching modalities on lower-limb range of motion measurements in recreational dancers.Most stretching techniques are designed to place a "stress" on the musculoskeletal unit that will increase its resting length and range of motion (ROM). Twenty-four adolescent dancers participated in a 6-week intervention program that compared low-intensity stretching (Microstretching) with moderate-intensity static stretching on active and passive ranges of motion. Microstretching is a new modality that reduces the possibility of the parasympathetic system being activated. Repeated measures analysis indicated changes in ROM over the intervention period (p < 0.05), with the Microstretching group demonstrating greater increases in passive and active ROM than the static stretch group (p < 0.01); there was no noted bilateral differences in ROM. The results from this study agree with past studies that have found that stretching increases the compliance of any given muscle and therefore increases the range of motion. One main finding of the present study was that throughout a 6-week training program very-low-intensity stretching had a greater positive effect on lower-limb ROM than moderate-intensity static stretching. The most interesting aspect of the study was the greater increase in active ROM compared to passive ROM by the Microstretching group. This suggests that adaptation has occurred within the muscle itself to a greater extent than in structures of the hip joint. Practical application for this technique suggests it is beneficial as a postexercise modality that potentially has a restorative component.
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A longitudinal study of United Kingdom pharmacists' misdemeanours--trials, tribulations and trends.BACKGROUND: Standards of UK pharmacy practice are maintained by the Royal Pharmaceutical Society of Great Britain, which has the power to take a range of sanctions, including removal of the right to practice, against those found guilty of malpractice. This function is currently under review. OBJECTIVE: To conduct a longitudinal study in order to define trends and identify areas where remedial or preventative support could be focused. METHOD: Case analysis of reports of individuals' misdemeanours published in the British Pharmaceutical Journal over a 12-year period (September 1988-October 2000). Professional and personal misdemeanours were considered. MAIN OUTCOME MEASURE: Nature of misdemeanour, conviction or disciplinary proceedings against individual, practising pharmacists in the study period. Reasons offered for committing the misdemeanour and penalties applied. RESULTS: 344 cases, involving a wide range of personal (162) and professional (590) misdemeanours were found. On an annual basis, the maximum incidence of pharmacists found guilty of any misdemeanour was extremely low (< 0.1 of 1% on the pharmaceutical register). The most common professional misdemeanour was failure to keep adequate written records. The most common personal misdemeanour was fraud. The most common reason cited for committing any misdemeanour was financial gain. Numbers in individual offence categories were persistent but low and there were few obvious trends with time. The odds of involvement ratio for male versus female pharmacists was 7.36 (CI: 5.23-10.35) and for ethnic minority versus Caucasian pharmacists was 3.8 (CI: 3.06-4.72). The most stringent penalties (either imprisonment or removal of the right to practice and frequently both) were applied to cases involving personal use or trafficking of drugs subject to abuse. CONCLUSIONS: The current self-regulation of pharmacy practice in the UK involves a wide range of misdemeanours of varying severity; but the incidence of reports of pharmacists found guilty of malpractice was extremely low. The nature of misdemeanours appeared to change little over the period of the study; this study therefore indicates the spectrum of misdemeanours likely to be encountered by a regulating board in the immediate to medium-term future. If regulatory changes such as competence-based practice rights are introduced, the spectrum may change.
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A pilot study to determine the effectiveness of garlic oil capsules in the treatment of dyspeptic patients with Helicobacter pylori.BACKGROUND: Resistance of Helicobacter pylori to clarithromycin and metronidazole is now found worldwide. Steam-distilled garlic oil has in vitro activity against H. pylori and may be a useful alternative treatment strategy. MATERIALS AND METHODS: In this pilot study dyspeptic patients with positive serology for H. pylori confirmed by 13C urea breath test (UBT), at 0 and 2 weeks, were enrolled. Treatment consisted of one 4 mg garlic oil capsule with a meal four times per day for 14 days. H. pylori eradication was defined as a negative UBT at both follow-up appointments. Suppression was defined as a 50% fall in 13C excess between baseline and follow-up 1. RESULTS: Five patients completed the study. There was no evidence of either eradication or suppression of H. pylori or symptom improvement whilst taking garlic oil. CONCLUSION: These negative results show that, within the gastric milieu, garlic oil at this dose does not inhibit H. pylori. A higher dose administered for a longer time-period may be effective. Antibiotics are usually combined with a proton-pump inhibitor or bismuth salt, as the only antibiotic with any in vivo activity against H. pylori in monotherapy is clarithromycin. A proton pump inhibitor raises gastric pH and, by increasing bacterial division, may increase the in vivo activity of garlic oil. This may be worth pursuing in a future trial.
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A role for human endogenous retrovirus-K (HML-2) in rheumatoid arthritis: investigating mechanisms of pathogenesis.Human endogenous retroviruses (HERVs) are remnants of ancient retroviral infections within the human genome. These molecular fossils draw parallels with present-day exogenous retroviruses and have been linked previously with immunopathology within rheumatoid arthritis (RA). Mechanisms of pathogenesis for HERV-K in RA such as molecular mimicry were investigated. To clarify a role for HERVs in RA, potential autoantigens implicated in autoimmunity were scanned for sequence identity with retroviral epitopes. Short retroviral peptides modelling shared epitopes were synthesized, to survey anti-serum of RA patients and disease controls. A novel real-time polymerase chain reaction (PCR) assay was also developed to quantify accurately levels of HERV-K (HML-2) gag expression, relative to normalized housekeeping gene expression. Both serological and molecular assays showed significant increases in HERV-K (HML-2) gag activity in RA patients, compared to disease controls. The real-time PCR assay identified significant up-regulation in HERV-K mRNA levels in RA patients compared to inflammatory and healthy controls. Exogenous viral protein expression and proinflammatory cytokines were also shown to exert modulatory effects over HERV-K (HML-2) transcription. From our data, it can be concluded that RA patients exhibited significantly elevated levels of HERV-K (HML-2) gag activity compared to controls. Additional factors influencing HERV activity within the synovium were also identified. The significant variation in RA patients, both serologically and transcriptionally, may be an indication that RA is an umbrella term for a number of separate disease entities, of which particular HERV polymorphisms may play a role in development.
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A sychnological cell penetrating peptide mimic of p21(WAF1/CIP1) is pro-apoptogenic.Targeting chemotherapeutic agents directly to sites of DNA replication and repair within cancerous cells is problematic. This study attempts to address the issue of nuclear delivery of biologically active peptides with the potential to disrupt cancer cell growth. Herein, the protein transduction domain of the HIV-1 transactivator of transcription, Tat (Tat(48-60)), is used to deliver a cytotoxic peptide mimic of the cyclin-dependent kinase inhibitor, p21(WAF1/CIP1) into the nucleus. This construct, which we designate as Tat(48-60)-P10, contains the PCNA interacting protein (PIP) box. We demonstrate the utility of Tat(48-60) for peptide delivery to the nucleus and show that Tat(48-60)-P10 induces apoptosis specific to the inclusion of the wild type PIP box containing sequence. Colocalization of Tat(48-60)-P10 with nuclear PCNA was observed by immunofluorescence analysis, supporting the hypothesis that cytotoxicity is potentially related to disruption of nuclear PCNA function. The U251 and U373 glioma cell lines exhibited particular sensitivity to the construct.
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A2 milk enhances dynamic muscle function following repeated sprint exercise, a possible ergogenic aid for a1-protein intolerant athletes?Hyperaminoacidemia following ingestion of cows-milk may stimulate muscle anabolism and attenuate exercise-induced muscle damage (EIMD). However, as dairy-intolerant athletes do not obtain the reported benefits from milk-based products, A2 milk may offer a suitable alternative as it lacks the A1-protein. This study aimed to determine the effect of A2 milk on recovery from a sports-specific muscle damage model. Twenty-one male team sport players were allocated to three independent groups: A2 milk (n = 7), regular milk (n = 7), and placebo (PLA) (n = 7). Immediately following muscle-damaging exercise, participants consumed either A2 milk, regular milk or PLA (500 mL each). Visual analogue scale (muscle soreness), maximal voluntary isometric contraction (MVIC), countermovement jump (CMJ) and 20-m sprint were measured prior to and 24, 48, and 72 h post EIMD. At 48 h post-EIMD, CMJ and 20-m sprint recovered quicker in A2 (33.4 ± 6.6 and 3.3 ± 0.1, respectively) and regular milk (33.1 ± 7.1 and 3.3 ± 0.3, respectively) vs. PLA (29.2 ± 3.6 and 3.6 ± 0.3, respectively) (p < 0.05). Relative to baseline, decrements in 48 h CMJ and 20-m sprint were minimised in A2 (by 7.2 and 5.1%, respectively) and regular milk (by 6.3 and 5.2%, respectively) vs. PLA. There was a trend for milk treatments to attenuate decrements in MVIC, however statistical significance was not reached (p = 0.069). Milk treatments had no apparent effect on muscle soreness (p = 0.152). Following muscle-damaging exercise, ingestion of 500 mL of A2 or regular milk can limit decrements in dynamic muscle function in male athletes, thus hastening recovery and improving subsequent performance. The findings propose A2 milk as an ergogenic aid following EIMD, and may offer an alternative to athletes intolerant to the A1 protein.
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Acid phosphatases.Acid phosphatases (APs) are a family of enzymes that are widespread in nature, and can be found in many animal and plant species. Mystery surrounds the precise functional role of these molecular facilitators, despite much research. Yet, paradoxically, human APs have had considerable impact as tools of clinical investigation and intervention. One particular example is tartrate resistant acid phosphatase, which is detected in the serum in raised amounts accompanying pathological bone resorption. This article seeks to explore the identity and diversity of APs, and to demonstrate the relation between APs, human disease, and clinical diagnosis.
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Acute adrenal failure: A potentially fatal consequence of an adulterated herbal remedy© 2019 BMJ Publishing Group Limited. Herbal remedies adulterated with glucocorticoids can cause Cushing's syndrome. We report a severe presentation of a 'herbal remedy' adulterated with glucocorticoids; causing a potentially fatal adrenal crisis precipitated by acute illness. Investigations were consistent with adrenal suppression and confirmed, after tablet analysis, to be due to a 'herbal remedy' containing synthetic betamethasone/dexamethasone. This case highlights the need for clinical vigilance and patient education about the potential risks associated with the use of unlicensed treatments and the role of tablet analysis in routine biochemistry.
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Acute and short-term effects of secondhand smoke on lung function and cytokine production.RATIONALE: The acute effect of secondhand smoke (SHS) on lung function and the duration of system disruption remain unknown. OBJECTIVES: To assess the SHS effects and their duration on lung function and inflammatory markers. METHODS: In a randomized single-blind crossover experiment data were obtained from 16 (8 women) nonsmoking adults at baseline and at 0, 1, and 3 hours after a 1-hour SHS exposure set at bar/restaurant SHS levels. MEASUREMENTS AND MAIN RESULTS: Serum and urine cotinine, lung function, and cytokines IL-4, IL-5, IL-6, tumor necrosis factor (TNF)-alpha, and IFN-gamma. At 0 hours most lung function parameters were significantly reduced (indicative: FEV(1), 4.3 +/- 0.4 vs. 3.8 +/- 0.3 L; FEV(1)/FVC, 0.9 +/- 0.1 vs. 0.8 +/- 0.1; P < 0.05) but at 3 hours they were at baseline levels. In contrast, cotinine (serum, 8.9 +/- 3.2 vs. 35.5 +/- 10.2 ng x ml(-1)), IL-4 (41.3 +/- 5.8 vs. 44.2 +/- 4.5 pg x ml(-1)), IL-5 (36.1 +/- 3.2 vs. 60.1 +/- 7.0 pg x ml(-1)), IL-6 (2.5 +/- 0.3 vs. 7.6 +/- 1.4 pg x ml(-1)) and IFN-gamma (0.3 +/- 0.2 vs. 0.6 +/- 0.2 IU x ml(-1)) at 3 hours were higher than at baseline (P < 0.05). IL-4 and TNF-alpha increased only in men, whereas IL-5, IL-6, and IFN-gamma were different between sexes after exposure (P < 0.05). Regression analyses revealed inverse associations of FEV(1) and FEV(1)/FVC ratio with IL-5 (P < 0.05) in men and with IL-5 (P = 0.01), IL-6 (P < 0.001), IFN-gamma (P = 0.034) and serum cotinine (P < 0.001) in women. CONCLUSIONS: We conclude that 1 hour of SHS exposure at bar/restaurant levels is accompanied by significant decrements on lung function and marked increases in inflammatory cytokines, particularly in men. More importantly, whereas most smoke-induced effects on lung function appear to recede within 60 minutes, inflammatory cytokines remain elevated for at least 3 hours after exposure to SHS.
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Acute rise of circulating vascular endothelial growth factor-A in patients with coronary artery disease following cardiothoracic surgery.AIMS: Vascular endothelial growth factor-A (VEGF-A) is an angiogenic and vasoprotective molecule whose expression is modulated by hypoxia and inflammatory mediators. Here we have tested the hypothesis that plasma levels of VEGF-A are influenced by pre-existing coronary artery disease and by changes in circulating interleukin-6 (IL-6). METHODS AND RESULTS: Plasma VEGF-A and IL-6 were measured prior to and at various time intervals following surgery in individuals with angiographically normal coronary arteries requiring cardiac valve replacement (N group) and in patients with coronary artery disease and stable angina undergoing coronary artery bypass grafting (CAD group). Baseline VEGF-A levels were not significantly different in CAD (22.3+/-2.6 pg x ml(-1)) compared to the N group (14.9+/-2.9 pg x ml(-1)). Following cardiac surgery there was a significant rise of VEGF-A in CAD (P<0.0005 vs baseline), but not in the N group, reaching a maximum (approximately 2 fold increase) after 24 h. Surgery caused a rapid increase of plasma IL-6 in both groups, but the rise was significantly larger in CAD patients (P<0.0005 vs N) where it preceded the increase in VEGF-A. Furthermore, in patients with CAD there was a significant correlation between the change in VEGF-A and the change in IL-6 (P<0.04). CONCLUSION: These findings demonstrate that in patients with coronary artery disease cardiothoracic surgery leads to an acute rise in VEGF-A. We suggest that this rise may result from an interaction between the pre-existing atheromatous process and a systemic increase of inflammatory mediators.
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Adenovirus vector-mediated delivery of the prodrug-converting enzyme carboxypeptidase G2 in a secreted or GPI-anchored form: High-level expression of this active conditional cytotoxic enzyme at the plasma membrane.Carboxypeptidase G2 (CPG2) is a powerful prodrug-converting enzyme. Without a requirement for endogenous enzymes or cofactors, it can directly activate mustard alkylating prodrugs to cytotoxic species, killing both quiescent and dividing cells. This paper provides the first report of its use in the context of a clinically relevant delivery vehicle using adenovirus vectors. To strengthen the efficacy of the prodrug-activating system, the enzyme has been engineered to be secreted or glycosylphosphatidylinositol (GPI) anchored to the extracellular membrane of tumor cells, resulting in an enhanced bystander effect by facilitating diffusion of the active drug through extracellular, rather than intracellular, activation. Using the vectors, we have achieved expression of functional secreted or GPI-anchored CPG2 in a panel of tumor cell lines demonstrating no loss in efficacy as a result of GPI anchor retention. Despite variable transduction efficiencies inherent to these vectors, greater than 50% cell kill was achievable in all of the cell lines tested following only a single exposure to the prodrug ZD2767P. Even in cell lines refractive to infection with the vectors, substantial cell death was recorded, indicative of the enhanced bystander effect generated following extracellular prodrug activation. A direct evaluation of the efficacy of our system has been made against adenoviral delivery of herpes simples virus thymidine kinase plus ganciclovir (GCV), a suicide gene therapy approach already in the clinic. In a short-term human glioma culture (IN1760) resistant to the clinical chemotherapeutic drug CCNU (1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea), thymidine kinase/GCV effected no cell killing compared to 70% cell killing with our system.
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Adenovirus-mediated expression of HSV1-TK or Fas ligand induces cell death in primary human glioma-derived cell cultures that are resistant to the chemotherapeutic agent CCNU.Due to minimal treatment success with surgery, radiotherapy, and chemotherapy, the aim of this study was to test the therapeutic potential of gene therapy for the treatment of glioblastoma multiforme (GBM). We have quantitatively analyzed two gene therapy approaches using short-term human glioma cell cultures derived from surgical biopsies (designated IN859, IN1612, IN2045, IN1760, and IN1265) and compared the results of gene therapy with the chemosensitivity of the same cells. All of the glioma cell cultures tested were susceptible to recombinant adenovirus (RAd)-mediated infection. Expression of herpes simplex virus type 1-thymidine kinase (RAd128), followed by ganciclovir treatment, induced apoptosis in all of the glioma cell cultures studied, including three that are resistant to the chemotherapeutic drug 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU). Expression of murine Fas ligand (RAdhCMV-mFasL) also induced cell death in four of the five cell cultures studied. One cell culture that was resistant to CCNU was also resistant to apoptosis induced by mFasL expression. These results suggest that sensitivity to chemotherapeutic agents does not necessarily correlate with the sensitivity to gene therapy treatments. RAds expressing therapeutic gene products in human glioma cell cultures are able to induce apoptosis even in some cells that are resistant to a commonly used chemotherapeutic agent. Therefore, RAd-mediated gene transfer could be a good candidate to further develop gene therapy for the treatment of GBM.
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Age-related alterations in blood and colonic dendritic cell propertiesBackground: Dendritic cells (DC) determine initiation, type and location of immune responses and, in adults, show decreased Toll-like receptors and some increased cytokine levels on ageing. Few studies in children have characterised DC or explored DC-related mechanisms producing age-related immune changes. Results: The pDC marker BDCA2 (but not CD123) was absent in pre-pubertal children and numbers of pDC decreased with age. Blood and colonic DC were more mature and activated in adults. Decrease in pDC numbers correlated with reduced GM-CSF levels with aging, but increasing IL-4 and IL-8 levels correlated with a more activated DC profile in blood. CXCL16 levels decreased with age. Methods: Blood and colonic DC phenotypes were determined in healthy adults and children by flow cytometry and correlated with aging. Blood DC were divided into plasmacytoid (pDC) and myeloid (mDC) while only mDC were identified in colon. Serum cytokine levels were determined by multiplex cytokine assays and correlated with DC properties. Conclusions: In children, lack of BDCA2, a receptor mediating antigen capture and inhibiting interferon induction, may be immunologically beneficial during immune development. Conversely, reduced pDC numbers, probably secondary to decreasing GM-CSF and increasing cytokine-induced maturation of DC are likely to determine deteriorating immunity with ageing.
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Age-related responses in circulating markers of redox status in healthy adolescents and adults during the course of a training macrocycleRedox status changes during an annual training cycle in young and adult track and field athletes and possible differences between the two age groups were assessed. Forty-six individuals (24 children and 22 adults) were assigned to four groups: trained adolescents, (TAD, N=13), untrained adolescents (UAD, N=11), trained adults (TA, N=12), and untrained adults (UA, N=10). Aerobic capacity and redox status related variables [total antioxidant capacity (TAC), glutathione (GSH), catalase activity, TBARS, protein carbonyls (PC), uric acid, and bilirubin] were assessed at rest and in response to a time-trial bout before training, at mid- and posttraining. TAC, catalase activity, TBARS, PC, uric acid, and bilirubin increased and GSH declined in all groups in response to acute exercise independent of training status and age. Training improved aerobic capacity, TAC, and GSH at rest and in response to exercise. Age affected basal and exercise-induced responses since adults demonstrated a greater TAC and GSH levels at rest and a greater rise of TBARS, protein carbonyls, and TAC and decline of GSH in response to exercise. Catalase activity, uric acid, and bilirubin responses were comparable among groups. These results suggest that acute exercise, age, and training modulate the antioxidant reserves of the body.
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Ambulatory care management of 69 patients with acute severe ulcerative colitis in comparison to 695 inpatients: Insights from a multicentre UK cohort studyIntroduction Acute severe ulcerative colitis (ASUC) traditionally requires inpatient hospital management for intravenous therapies and/or colectomy. Ambulatory ASUC care has not yet been evaluated in large cohorts. Aims We used data from PROTECT, a UK multicentre observational COVID-19 inflammatory bowel disease study, to report the extent, safety and effectiveness of ASUC ambulatory pathways. Methods Adults (≥18 years old) meeting Truelove and Witts criteria between 1 January 2019-1 June 2019 and 1 March 2020-30 June 2020 were recruited to PROTECT. We used demographic, disease phenotype, treatment outcomes and 3-month follow-up data. Primary outcome was rate of colectomy during the index ASUC episode. Secondary outcomes included corticosteroid response, time to and rate of rescue or primary induction therapy, response to rescue or primary induction therapy, time to colectomy, mortality, duration of inpatient treatment and hospital readmission and colectomy within 3 months of index flare. We compared outcomes in three cohorts: (1) patients treated entirely in inpatient setting; ambulatory patients subdivided into; (2) patients managed as ambulatory from diagnosis and (3) patients hospitalised and subsequently discharged to ambulatory care for continued intravenous steroids. Results 37% (22/60) participating hospitals used ambulatory pathways. Of 764 eligible patients, 695 (91%) patients received entirely inpatient care, 15 (2%) patients were managed as ambulatory from diagnosis and 54 (7%) patients were discharged to ambulatory pathways. Aside from younger age in patients treated as ambulatory from diagnosis, no significant differences in disease or patient phenotype were observed. The rate of colectomy (15.0% (104/695) vs 13.3% (2/15) vs 13.0% (7/54), respectively, p=0.96) and secondary outcomes were similar among all three cohorts. Stool culture and flexible sigmoidoscopy were less frequently performed in ambulatory cohorts. Forty per cent of patients treated as ambulatory from diagnosis required subsequent hospital admission. Conclusions In a post hoc analysis of one of the largest ASUC cohorts collected to date, we report an emerging UK ambulatory practice which challenges treatment paradigms. However, our analysis remains underpowered to detect key outcome measures and further studies exploring clinical and cost-effectiveness as well as patient and physician acceptability are needed. Trial registration number NCT04411784.
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An international study on dietary supplementation use in dancersLittle is known of the prevalence and motives of dietary supplement use amongst dancers from different cultures. Investigating supplement use, presumed effects, and other factors may be crucial for improving educational and nutritional advice provided for this cohort. Therefore, this study investigated the use of dietary supplements in 334 dancers from 53 countries, who completed a digitally based 35-question survey detailing demographic information and the use of dietary supplementation. Supplement use was prevalent amongst this international cohort, with 48% reporting regular supplement use. Major motives for supplement use were to improve health, boost immunity, and reduce fatigue. Forty-five percent believed that dancing increased the need for supplementation, whilst 30% recognized that there were risks associated with nutritional supplementation. The most frequently consumed supplements were vitamin C (60%), multivitamins (67%), and caffeine (72%). A smaller group of participants declared the use of whey protein (21%) or creatine (14%). Supplements were mainly obtained from pharmacies, supermarkets, and health-food stores. Dancers recognized their lack of knowledge in dietary supplement use and relied on peer recommendations instead of sound evidence-based advice from acknowledged nutrition or health care professionals. This study demonstrates that dietary supplement use is internationally prevalent amongst dancers. Continued efforts are warranted with regard to information dissemination.
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Angiogenesis in chronically ischaemic human heart following percutaneous myocardial revascularisation.Patients with intractable angina and severe diffuse coronary artery disease not amenable to conventional revascularisation therapy have relatively few treatment options. A number of studies suggest myocardial laser revascularisation is of clinical benefit in such patients.1, 2 Percutaneous myocardial revascularisation (PMR) involves the use of an intravascular catheter, positioned within the left ventricular cavity under fluoroscopic guidance, to deliver controlled bursts of holmium:YAG laser energy. PMR results in the formation of small channels (~1.75 mm diameter) that extend from the endocardial surface partly into the myocardial wall. Many uncontrolled studies suggest that PMR provides symptomatic relief, although the first randomised controlled trial demonstrated no benefit over a sham procedure.3 It has been suggested that PMR induces angiogenesis, although many other mechanisms of action have been suggested. To determine whether PMR has any effects on angiogenesis in the human ischaemic myocardium we have undertaken a detailed histological and immunohistochemical examination of the hearts of two patients who died eight weeks and 52 weeks after apparently symptomatically successful PMR therapy. In this first detailed study of human myocardium subjected to percutaneous myocardial laser revascularisation, we report evidence of sustained myocardial neovascularisation in treated areas and of the presence of vascular endothelial growth factor (VEGF). Unexpectedly, most of the neovessels are abnormal and immature, lacking a smooth muscle coat. Furthermore, neovessels are largely confined to scar tissue. Both the above factors are likely to limit the extent to which angiogenesis following PMR could improve perfusion. In a broader context, our findings that, once formed, immature and abnormal neovessels are sustained long term in human myocardium, may be relevant to the general design of strategies for therapeutic angiogenesis in patients—for example, the direct application of angiogenic factors (or genes).
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Ankle and foot contributions to extreme plantar- and dorsiflexion in female ballet dancers.Background: Female ballet dancers require extreme ankle motion. The objective of this study was to quantify the relative contributions of the ankle and various foot joints to extreme plantarflexion (PF) and dorsiflexion (DF) in female ballet dancers using an X-ray superimposition technique and digital graphics software. Materials and Methods: One asymptomatic ankle was studied in each of seven experienced female ballet dancers. Three lateral weightbearing X-rays were taken of each ballet dancer's ankle: en pointe (maximum PF), in neutral position, and in demi-plié (maximum DF). Using graphics software, a subject's three X-ray images were superimposed and the tali were aligned. On each image the tibia, navicular, intermediate cuneiform, and first metatarsal were marked. Positional differences of a bone's line among the three images demonstrated angular movement of the bone in degrees. The neutral position was the reference from which both PF and DF of the bones were calculated. Results: The talocrural joint contributed the most motion of any pair of bones evaluated for both PF and DF, with mean movements of 57.6 ± 5.2 degrees en pointe and 24.6 ± 9.6 degrees in demi-plié. Approximately 70% of total PF and DF were attributable to the talocrural joint, with the remaining 30% coming from motion between adjacent pairs of the studied foot bones. Conclusion: Superimposed X-rays for assessing ankle and foot contributions to the extreme positions required of female ballet dancers offer insight into how these positions are attained that is not available via goniometry. Clinical Relevance: Functional information gained from this study may assist clinicians in assessessing ankle and foot pain in these individuals.