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31.
In the context of collateral circulation of the heart, the role of extra-cardiac collateral arteries has been thought to be negligible. We present a case in which such collateral vessel acted as a rescue, subsequent to a failed revascularisation attempt. With surgeons nowadays considering ‘less is more’ in terms of grafting in coronary artery bypass grafting (CABG), and more evidence arising in favour of medical therapy, we need to re-assess the role of these collateral vessels in the coronary circulation. 相似文献
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33.
Edward F. McKone Emily A. DiMango Sivagurunathan Sutharsan Tara Lynn Barto Daniel Campbell Neil Ahluwalia Mark Higgins Caroline A. Owen Elizabeth Tullis 《Journal of cystic fibrosis》2021,20(2):234-242
BackgroundTezacaftor (TEZ)/ivacaftor (IVA) is an approved CFTR modulator shown to be efficacious and generally safe and well tolerated in people ≥12 years of age with cystic fibrosis (CF) homozygous for the F508del-CFTR mutation or heterozygous for the F508del-CFTR mutation and a residual function mutation. Although previous studies with IVA alone showed clinical benefits in people with CFTR gating mutations, TEZ/IVA has not yet been evaluated in a Phase 3 study of participants heterozygous for F508del-CFTR and a gating mutation (F/gating genotypes). Here, we present results from a randomized, double-blind, IVA-controlled, parallel-group, Phase 3 study assessing the efficacy, safety, and pharmacokinetics (PK) of TEZ/IVA in participants ≥12 years of age with F/gating genotypes.MethodsEnrolled participants entered a 4-week IVA run-in period to create a stable IVA baseline. Participants were then randomized to receive IVA or TEZ/IVA for 8 weeks in an active comparator treatment period (ACTP). The primary endpoint was absolute change in percent predicted forced expiratory volume in 1 second (ppFEV1). Key secondary endpoints were relative change in ppFEV1 and absolute change in CF Questionnaire–Revised respiratory domain score. Secondary endpoints included absolute change in sweat chloride (SwCl) concentration, PK parameters, and safety. All endpoints except PK parameters and safety were assessed from baseline through Week 8.ResultsSixty-nine participants (92.0%) in the IVA group and 75 participants (98.7%) in the TEZ/IVA group completed treatment. No improvements were seen in efficacy endpoints from baseline at the end of the IVA run-in period through the end of the ACTP in the IVA group. No significant differences in ppFEV1 or any key secondary endpoint were observed between the IVA and TEZ/IVA groups. SwCl concentrations decreased more in the TEZ/IVA versus IVA group during the ACTP. The safety profile and PK parameters of TEZ/IVA were consistent with those of previous studies in participants ≥12 years of age with CF.ConclusionsThis Phase 3 study showed that the dual-combination regimen of TEZ/IVA demonstrated clinical efficacy but did not have significantly greater clinical efficacy than IVA alone in participants ≥12 years of age with F/gating genotypes. However, as reported in other studies, TEZ/IVA was generally safe and well tolerated (NCT02412111). 相似文献
34.
Roger Suau Marta Vidal Ruth Aguilar Gemma Ruiz-Olalla Miquel Vázquez-Santiago Chenjerai Jairoce Augusto J. Nhabomba Ben Gyan David Dosoo Kwaku Poku Asante Seth Owusu-Agyei Joseph J. Campo Luis Izquierdo David Cavanagh Ross L. Coppel Virander Chauhan Evelina Angov Sheetij Dutta Carlota Dobaño 《Vaccine》2021,39(4):687-698
BackgroundThe evaluation of immune responses to RTS,S/AS01 has traditionally focused on immunoglobulin (Ig) G antibodies that are only moderately associated with protection. The role of other antibody isotypes that could also contribute to vaccine efficacy remains unclear. Here we investigated whether RTS,S/AS01E elicits antigen-specific serum IgA antibodies to the vaccine and other malaria antigens, and we explored their association with protection.MethodsNinety-five children (age 5–17 months old at first vaccination) from the RTS,S/AS01E phase 3 clinical trial who received 3 doses of RTS,S/AS01E or a comparator vaccine were selected for IgA quantification 1 month post primary immunization. Two sites with different malaria transmission intensities (MTI) and clinical malaria cases and controls, were included. Measurements of IgA against different constructs of the circumsporozoite protein (CSP) vaccine antigen and 16 vaccine-unrelated Plasmodium falciparum antigens were performed using a quantitative suspension array assay.ResultsRTS,S vaccination induced a 1.2 to 2-fold increase in levels of serum/plasma IgA antibodies to all CSP constructs, which was not observed upon immunization with a comparator vaccine. The IgA response against 13 out of 16 vaccine-unrelated P. falciparum antigens also increased after vaccination, and levels were higher in recipients of RTS,S than in comparators. IgA levels to malaria antigens before vaccination were more elevated in the high MTI than the low MTI site. No statistically significant association of IgA with protection was found in exploratory analyses.ConclusionsRTS,S/AS01E induces IgA responses in peripheral blood against CSP vaccine antigens and other P. falciparum vaccine-unrelated antigens, similar to what we previously showed for IgG responses. Collectively, data warrant further investigation of the potential contribution of vaccine-induced IgA responses to efficacy and any possible interplay, either synergistic or antagonistic, with protective IgG, as identifying mediators of protection by RTS,S/AS01E immunization is necessary for the design of improved second-generation vaccines.Clinical trial registration: ClinicalTrials.gov: NCT008666191. 相似文献
35.
Ashley Lacombe-Duncan PhD MSW Hannah Kia PhD MSW Carmen H. Logie PhD MSW Kieran P. Todd BA Yasmeen Persad Gabrielle Leblanc Kelendria Nation Ayden I. Scheim PhD Tara Lyons PhD Chavisa Horemans MES BFA Mona Loutfy MD FRCPC MPH 《Health & social care in the community》2021,29(5):e33-e46
Transgender (trans) women experience barriers to access to HIV care, which result in their lower engagement in HIV prevention, treatment and support relative to cisgender people living with HIV. Studies of trans women's barriers to HIV care have predominantly focused on perspectives of trans women, while barriers are most often described at provider, organisation and/or systems levels. Comparing perspectives of trans women and service providers may promote a shared vision for achieving health equity. Thus, this qualitative study utilised focus groups and semi-structured interviews conducted 2018–2019 to understand barriers and facilitators to HIV care from the perspectives of trans women (n = 26) and service providers (n = 10). Barriers endorsed by both groups included: (a) anticipated and enacted stigma and discrimination in the provision of direct care, (b) lack of provider knowledge of HIV care needs for trans women, (c) absence of trans-specific services/organisations and (d) cisnormativity in sexual healthcare. Facilitators included: (a) provision of trans-positive trauma-informed care, (b) autonomy and choice for trans women in selecting sexual health services and (c) models for trans-affirming systems change. Each theme had significant overlap, yet nuanced perspective, between trans women and service providers. Specific recommendations to improve HIV care access for trans women are discussed. These recommendations can be used by administrators and service providers alike to work collaboratively with trans women to reduce barriers and facilitators to HIV care and ultimately to achieve health equity for trans women. 相似文献
36.
Martin Kolev Tara Barbour Scott Baver Cedric Francois Pascal Deschatelets 《Immunological reviews》2023,313(1):358-375
C3 is a key complement protein, located at the nexus of all complement activation pathways. Extracellular, tissue, cell-derived, and intracellular C3 plays critical roles in the immune response that is dysregulated in many diseases, making it an attractive therapeutic target. However, challenges such as very high concentration in blood, increased acute expression, and the elevated risk of infections have historically posed significant challenges in the development of C3-targeted therapeutics. This is further complicated because C3 activation fragments and their receptors trigger a complex network of downstream effects; therefore, a clear understanding of these is needed to provide context for a better understanding of the mechanism of action (MoA) of C3 inhibitors, such as pegcetacoplan. Because of C3's differential upstream position to C5 in the complement cascade, there are mechanistic differences between pegcetacoplan and eculizumab that determine their efficacy in patients with paroxysmal nocturnal hemoglobinuria. In this review, we compare the MoA of pegcetacoplan and eculizumab in paroxysmal nocturnal hemoglobinuria and discuss the complement-mediated disease that might be amenable to C3 inhibition. We further discuss the current state and outlook for C3-targeted therapeutics and provide our perspective on which diseases might be the next success stories in the C3 therapeutics journey. 相似文献
37.
R. Bulat E. Fachnie U. Chauhan Ying Chen & G. Tougas 《Alimentary pharmacology & therapeutics》1999,13(6):805-812
BACKGROUND: Spearmint is commonly used as an antispasmodic and as a flavouring in several medications including antacids. It can produce heartburn, presumably by lowering lower oesophageal sphincter (LES) tone, but the mechanism has not previously been objectively examined. AIM: To study the effect of spearmint on LES function, acid reflux and symptoms. METHODS: In healthy volunteers, a Dent Sleeve and a pH electrode were placed in the distal oesophagus. They were then given spearmint either in a flavouring (0.5 mg), or a high (500 mg) dose, or a placebo, using a double-blind randomized crossover design. LES pressure, oesophageal pH and symptoms were recorded for 30 min before and after administration. RESULTS: LES pressure was not affected by spearmint, either high dose (19.6 vs. 16.0 mmHg), flavouring dose (20.2 vs. 19.8 mmHg) or placebo (20.5 vs. 19.2 mmHg, all N.S.). There were no differences in reflux occurrence following high dose (mean = 0.65 vs. 0.85 episodes), low dose (0.4 vs. 0.5 episodes) or placebo (0.7 vs. 1.10 episodes, all N.S.). There was a significant increase in mean symptom scores following high-dose spearmint (0 vs. 0.35, P = 0.03), but not low dose (0 vs. 0.2) or placebo (0 vs. 0.5, both N.S.). One subject reported symptoms with placebo, one with low dose, and six with high dose; all without increased reflux episodes or decreased sphincter pressure. CONCLUSION: Spearmint has no effect on LES pressure or acid reflux. Flavouring doses of spearmint do not produce more symptoms than placebo while high doses can be associated with symptoms, presumably from direct mucosal irritation but not reflux. 相似文献
38.
Tara L. McLaughlin 《Substance Abuse》2003,24(1):73-75
The book reviewed in this article discusses the use of brief interventions in the treatment of adolescent substance abuse. Topics covered include the developmental context within which adolescent substance use occurs, the use of the harm reduction approach to reduce substance use, current assessment instruments, and the role of cognitive and genetic factors in the etiology of substance abuse. Examples of specific brief interventions with adolescents are described and possible avenues for future transdisciplinary research are explored. This expansive sourcebook will be of value to clinicians and academicians alike. 相似文献
39.
Pure red cell aplasia (PRCA) is characterized by severe anemia, reticulocytopenia, marked selective hypoplasia of the erythroid precursor cells in the bone marrow and normal peripheral leukocyte and platelet counts. We reported two cases of diphenylhydantoin (DPH)-induced PRCA after neurological surgery. They recovered completely with discontinuance of DPH therapy. Neurosurgeons should be aware of this side effect because most reported cases of PRCA have occurred about a few months after neurological surgery under general anaesthesia and DPH therapy. 相似文献
40.
Personal exposure to nitrogen dioxide and risk of airflow obstruction in asthmatic children with upper respiratory infection
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BACKGROUND: Several studies have linked air pollution by nitrogen dioxide (NO(2)) with increased hospital admissions for asthma in children. Exacerbations of asthma in children are often precipitated by upper respiratory infections. It is therefore possible that NO(2) increases the risk of airways obstruction when asthmatic children develop upper respiratory infections. METHODS: To test this hypothesis a sample of 114 asthmatic children aged 7-12 years were followed for a total of up to 13 months. Probable upper respiratory infections were identified by consensus review of daily symptom diaries, and episodes of airways obstruction from serial records of peak expiratory flow (PEF). Personal exposures to NO(2) were measured with Palmes tubes that were changed weekly. Generalised estimating equations were used to assess the relative risk (RR) of an asthmatic exacerbation starting within seven days of an upper respiratory infection according to estimated NO(2) exposure during the one week period from two days before to four days after the onset of the infection. RESULTS: The children were followed for an average of 34 weeks during which 318 upper respiratory infections and 224 episodes of reduced PEF were diagnosed. PEF episodes were much more likely to occur in the seven days following the onset of an upper respiratory infection than at other times. Estimated exposures to NO(2) at the time of infections were generally low (geometric mean 10.6 microg/m(3)). Compared with exposures of < or = 8 microg/m(3), exposures of >28 microg/m(3) were associated with a RR of 1.9 (95% confidence interval 1.1 to 3.4) for the development of an asthmatic episode within seven days of an infection. CONCLUSIONS: The findings give some support to the hypothesis that NO(2) increases the risk of asthmatic exacerbations following respiratory infections, even at relatively low levels of exposure. Further studies in populations with higher exposures would be useful. 相似文献