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Background: Bacteriophage (phage) therapy is a promising alternative antimicrobial approach that has the potential to transform the way we treat bacterial infections. The antibiotic resistance crisis is driving renewed interest in phage therapy. There are currently no licensed phage therapy medicinal products and phage therapy is used in small but growing patient numbers on an unlicensed basis., Objectives: This article provides guidelines on the assessment of patient suitability for unlicensed phage therapy for clinicians in the United Kingdom., Sources: This article builds on Health Improvement Scotland's recommendation for the consideration of phage therapy in difficult-to-treat infections and the experience of the author group, who have collectively assessed the suitability of 30 patients for phage therapy., Content: In the United Kingdom, unlicenced medicines, including phages, may be considered to meet special clinical needs. The use of unlicenced medicines is governed by national legislation and local National Health Service trust policies. Phages can be used in any National Health Service trust and decisions about suitability should be made through existing local clinical management pathways. This article sets out guidelines to support local clinical teams in the assessment of patient suitability for phage therapy. Clinical and microbiological considerations are presented, including allergy and pregnancy., Implications: The assessment of patient suitability for phage therapy is within the scope of local clinical teams. Local assessment through existing clinical management pathways will develop confidence and competence in phage therapy among clinical teams nationally and ensure timely patient care., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: A series of phase 3 clinical trials have demonstrated that elexacaftor plus tezacaftor plus ivacaftor (ELX/TEZ/IVA) is safe and efficacious in people with cystic fibrosis (pwCF) aged ≥12 years with ≥1 F508del mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The impact of this treatment on lifetime clinical outcomes and survival, however, has yet to be assessed., Methods: We used a person-level microsimulation model to estimate the survival and lifetime clinical benefits of ELX/TEZ/IVA treatment versus other CFTR modulator combinations (tezacaftor plus ivacaftor [TEZ/IVA] or lumacaftor plus ivacaftor [LUM/IVA]) or best supportive care (BSC) alone in pwCF aged ≥12 years who are homozygous for F508del-CFTR. Disease progression inputs were derived from published literature; clinical efficacy inputs were derived from an indirect treatment comparison conducted using relevant phase 3 clinical trial data and extrapolations of clinical data., Results: The median projected survival for pwCF homozygous for F508del-CFTR treated with ELX/TEZ/IVA was 71.6 years. This was an increase of 23.2 years versus TEZ/IVA, 26.2 years versus LUM/IVA, and 33.5 years versus BSC alone. Treatment with ELX/TEZ/IVA also reduced disease severity as well as the number of pulmonary exacerbations and lung transplants. In a scenario analysis, the median projected survival for pwCF initiating ELX/TEZ/IVA between the ages of 12 and 17 years was 82.5 years, an increase of 45.4 years compared with BSC alone., Conclusions: The results from our model suggest ELX/TEZ/IVA treatment may substantially increase survival for pwCF, with early initiation potentially allowing pwCF to achieve near-normal life expectancy., Competing Interests: Declaration of Competing Interest Andrea Lopez, Conor Daly, Gabriela Vega-Hernandez, and Jaime L. Ru- bin are employees of Vertex Pharmaceuticals and might own stock or stock options in the company. Gordon MacGre- gor has no conflicts of interest to declare., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: Elexacaftor-tezacaftor-ivacaftor has been shown to be safe and efficacious in people with cystic fibrosis and at least one F508del allele. Our aim was to identify a novel cystic fibrosis transmembrane conductance regulator (CFTR) modulator combination capable of further increasing CFTR-mediated chloride transport, with the potential for once-daily dosing., Methods: We conducted two phase 2 clinical trials to assess the safety and efficacy of a once-daily combination of vanzacaftor-tezacaftor-deutivacaftor in participants with cystic fibrosis who were aged 18 years or older. A phase 2 randomised, double-blind, active-controlled study (VX18-561-101; April 17, 2019, to Aug 20, 2020) was carried out to compare deutivacaftor monotherapy with ivacaftor monotherapy in participants with CFTR gating mutations, following a 4-week ivacaftor monotherapy run-in period. Participants were randomly assigned to receive either ivacaftor 150 mg every 12 h, deutivacaftor 25 mg once daily, deutivacaftor 50 mg once daily, deutivacaftor 150 mg once daily, or deutivacaftor 250 mg once daily in a 1:1:2:2:2 ratio. The primary endpoint was absolute change in ppFEV 1 from baseline at week 12. A phase 2 randomised, double-blind, controlled, proof-of-concept study of vanzacaftor-tezacaftor-deutivacaftor (VX18-121-101; April 30, 2019, to Dec 10, 2019) was conducted in participants with cystic fibrosis and heterozygous for F508del and a minimal function mutation (F/MF genotypes) or homozygous for F508del (F/F genotype). Participants with F/MF genotypes were randomly assigned 1:2:2:1 to receive either 5 mg, 10 mg, or 20 mg of vanzacaftor in combination with tezacaftor-deutivacaftor or a triple placebo for 4 weeks, and participants with the F/F genotype were randomly assigned 2:1 to receive either vanzacaftor (20 mg)-tezacaftor-deutivacaftor or tezacaftor-ivacaftor active control for 4 weeks, following a 4-week tezacaftor-ivacaftor run-in period. Primary endpoints for part 1 and part 2 were safety and tolerability and absolute change in ppFEV 1 from baseline to day 29. Secondary efficacy endpoints were absolute change from baseline at day 29 in sweat chloride concentrations and Cystic Fibrosis Questionnaire-Revised (CFQ-R) respiratory domain score. These clinical trials are registered with ClinicalTrials.gov, NCT03911713 and NCT03912233, and are complete., Findings: In study VX18-561-101, participants treated with deutivacaftor 150 mg once daily (n=23) or deutivacaftor 250 mg once daily (n=24) had mean absolute changes in ppFEV 1 of 3·1 percentage points (95% CI -0·8 to 7·0) and 2·7 percentage points (-1·0 to 6·5) from baseline at week 12, respectively, versus -0·8 percentage points (-6·2 to 4·7) with ivacaftor 150 mg every 12 h (n=11); the deutivacaftor safety profile was consistent with the established safety profile of ivacaftor 150 mg every 12 h. In study VX18-121-101, participants with F/MF genotypes treated with vanzacaftor (5 mg)-tezacaftor-deutivacaftor (n=9), vanzacaftor (10 mg)-tezacaftor-deutivacaftor (n=19), vanzacaftor (20 mg)-tezacaftor-deutivacaftor (n=20), and placebo (n=10) had mean changes relative to baseline at day 29 in ppFEV 1 of 4·6 percentage points (-1·3 to 10·6), 14·2 percentage points (10·0 to 18·4), 9·8 percentage points (5·7 to 13·8), and 1·9 percentage points (-4·1 to 8·0), respectively, in sweat chloride concentration of -42·8 mmol/L (-51·7 to -34·0), -45·8 mmol/L (95% CI -51·9 to -39·7), -49·5 mmol/L (-55·9 to -43·1), and 2·3 mmol/L (-7·0 to 11·6), respectively, and in CFQ-R respiratory domain score of 17·6 points (3·5 to 31·6), 21·2 points (11·9 to 30·6), 29·8 points (21·0 to 38·7), and 3·3 points (-10·1 to 16·6), respectively. Participants with the F/F genotype treated with vanzacaftor (20 mg)-tezacaftor-deutivacaftor (n=18) and tezacaftor-ivacaftor (n=10) had mean changes relative to baseline (taking tezacaftor-ivacaftor) at day 29 in ppFEV 1 of 15·9 percentage points (11·3 to 20·6) and -0·1 percentage points (-6·4 to 6·1), respectively, in sweat chloride concentration of -45·5 mmol/L (-49·7 to -41·3) and -2·6 mmol/L (-8·2 to 3·1), respectively, and in CFQ-R respiratory domain score of 19·4 points (95% CI 10·5 to 28·3) and -5·0 points (-16·9 to 7·0), respectively. The most common adverse events overall were cough, increased sputum, and headache. One participant in the vanzacaftor-tezacaftor-deutivacaftor group had a serious adverse event of infective pulmonary exacerbation and another participant had a serious rash event that led to treatment discontinuation. For most participants, adverse events were mild or moderate in severity., Interpretation: Once-daily dosing with vanzacaftor-tezacaftor-deutivacaftor was safe and well tolerated and improved lung function, respiratory symptoms, and CFTR function. These results support the continued investigation of vanzacaftor-tezacaftor-deutivacaftor in phase 3 clinical trials compared with elexacaftor-tezacaftor-ivacaftor., Funding: Vertex Pharmaceuticals., Competing Interests: Declaration of interests AZU received grants from the Cystic Fibrosis Foundation and the CFF-Therapeutic Development Network for the present work; received payment or honoraria from Vertex Pharmaceuticals for presentations at CF Centers in UK; and participated in advisory boards for Vertex and Eloxx. VI received grant support from CF TDN for the present work; consulting fees from Mylan for CF—TOBI podhaler advisory board; and grant support from CFF for meeting attendance. PA received support from Vertex Pharmaceuticals for lectures, presentations, and materials; meeting attendance; and participation on data safety monitoring boards or advisory boards. MAM received payment from Vertex for the current work and personal fees for serving on an advisory board; grants from Vertex and from the German Ministry for Education and Research; consulting fees from Boehringer Ingelheim, Arrowhead Pharmaceuticals, Vertex Pharmaceuticals, Santhera, Sterna Biologicals, Enterprise Therapeutics, Antabio, and Abbvie; lecture fees from Boehringer Ingelheim, Arrowhead Pharmaceuticals, and Vertex Pharmaceuticals; travel reimbursement from Boehringer Ingelheim and Vertex Pharmaceuticals; personal fees for participation in an advisory board from Boehringer Ingelheim, Arrowhead Pharmaceuticals, Vertex Pharmaceuticals, Santhera, Enterprise Therapeutics, Antabio, Kither Biotech, Abbvie, and Pari; and serves as an ECFS Board member. EFM received grants and other payments or honoraria from Vertex; and support for meetings or travel from Menarini. BWR received payments from Vertex for the present work, and payments for a presentation in Vancouver, BC, Canada in 2019; and participated on data safety monitoring boards or advisory boards for CF Storm Clinical Trial, Vertex Pharmaceuticals, Janssen, Abbvie, and Insmed. SMR received support for a clinical trial; consulting fees on the design and conduct of clinical trials; support for meeting attendance and for his role as Co-Chair of the Next Generation Steering Committee; received grants or contracts from Novartis, TranslateBio, Galapagos–Abbvie, Synedgen–Synspira, Eloxx, Vertex Pharmaceuticals, and Ionis Astra Zenica; consulting fees from Novartis, Galapagos–Abbvie, Synedgen–Synspira, Vertex Pharmaceuticals, Renovion, Ionis, Cystetic Medicines, and Arcturus; support for meeting attendance from Vertex; has patents planned, issued or pending; serves as a Co-Chair of the Next Generation Steering Committee; and owns stock or stock options with Synedgen–Synspira and Renovion. RCR received clinical trial support and consulting fees from Vertex for the present work; grants from CFF, NIDDK, NHLBI, NICHD, and NIDCD; received consulting fees from Guidepoint Global, Gerson Lehrman Group, and Cystic Fibrosis Foundation; participated on a data safety monitoring or advisory board for NHLBI DSMB. JLT-C received personal consulting fees from Vertex for the present work; received grants from Vertex, Eloxx, and 4DMT for the conduct of a research trial; personal fees from Vertex, Insmed, and 4DMT for trial design consulting; personal fees from Vertex for non-branded speaking; and personal fees from AbbVie for her role as DMC Chair; served as the adult patient care representative to the CFF Board of Trustees, on the CF Foundation's Clinical Research Executive Committee, Clinical Research Advisory Board, and Racial Justice Working Group; as immediate past chair of the CF TDN's Sexual Health, Reproduction and Gender Research Working Group; on the scientific advisory board for Emily's Entourage; on the ATS Respiratory Health Awards Working Group; on the ATS Scientific Grant Review and Clinical Problems Assembly Programming Committees; and served as an associate editor for the Journal of Cystic Fibrosis. ET received payment for the present work and grants for doing clinical trials from Vertex Pharmaceuticals; received payment and reimbursement from Vertex for her role on a steering committee and for presentations at educational events. JB received funding from Vertex Pharmaceuticals for the present work. AH received funding from Vertex Pharmaceuticals for the present work; grant support from NIHR, CF Trust, CF Foundation, and Medical Research Council; payments for educational lectures from Vertex Pharmaceuticals and for an advisory board from Mylan; medical writing support from Vertex; served as Chair of the UK CF Clinical Trials Accelerator Platform and as a board member of the UK CF Medical Association. LMY received salary support from mgH TDN for clinical research activity for the present work. DW has patents planned, issued or pending. DW, LTW, CC, APM, NN, PRS, ST, FVG, and YX are Vertex employees and might own stocks or stock options. GM and CK have nothing to disclose. LV was a clinical pharmacology lead at Vertex during the conduct of this study and conducted PK data analysis for the present study., (Copyright © 2023 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background: Elexacaftor plus tezacaftor plus ivacaftor is a triple-combination cystic fibrosis transmembrane conductance regulator (CFTR) modulator regimen shown to be generally safe and efficacious in people with cystic fibrosis aged 12 years or older with at least one F508del-CFTR allele. We aimed to assess the magnitude and durability of the clinical effects of this triple combination regimen in people with cystic fibrosis homozygous for the F508del-CFTR mutation., Methods: We conducted a multicentre, randomised, double-blind, active-controlled, phase 3b trial of elexacaftor plus tezacaftor plus ivacaftor at 35 medical centres in Australia, Belgium, Germany, and the UK. Eligible participants were those with cystic fibrosis homozygous for the F508del-CFTR mutation, aged 12 years or older with stable disease, and with a percent predicted FEV 1 of 40-90% inclusive. After a 4-week run-in period, in which participants received tezacaftor 100 mg orally once daily and ivacaftor 150 mg orally every 12 h, participants were randomly assigned (1:1) to receive 24 weeks of either elexacaftor 200 mg orally once daily plus tezacaftor 100 mg orally once daily plus ivacaftor 150 mg orally every 12 h (elexacaftor plus tezacaftor plus ivacaftor group) or tezacaftor 100 mg orally once daily plus ivacaftor 150 mg orally every 12 h (tezacaftor plus ivacaftor group). Randomisation was stratified by percent predicted FEV 1 , age at screening visit, and whether the participant was receiving CFTR modulators at the time of the screening visit. Patients, investigators, and sponsor's study execution team were masked to treatment assignment. The primary endpoint was the absolute change in Cystic Fibrosis Questionnaire-Revised (CFQ-R) respiratory domain score from baseline (ie, at the end of the tezacaftor plus ivacaftor run-in period) up to and including week 24. The key secondary endpoint was the absolute change from baseline in percent predicted FEV 1 up to and including week 24; other secondary endpoints were the absolute change from baseline in sweat chloride concentrations up to and including week 24, and safety and tolerability. All endpoints were assessed in all randomised patients who had received at least one dose of their assigned regimen. This study is registered with ClinicalTrials.gov, NCT04105972., Findings: Between Oct 3, 2019, and July 24, 2020, 176 participants were enrolled. Following the 4-week tezacaftor plus ivacaftor run-in period, 175 participants were randomly assigned (87 to the elexacaftor plus tezacaftor plus ivacaftor group and 88 to the tezacaftor plus ivacaftor group) and dosed in the treatment period. From baseline up to and including week 24, the mean CFQ-R respiratory domain score increased by 17·1 points (95% CI 14·1 to 20·1) in the elexacaftor plus tezacaftor plus ivacaftor group and by 1·2 points (-1·7 to 4·2) in the tezacaftor plus ivacaftor group (least squares mean treatment difference 15·9 points [95% CI 11·7 to 20·1], p<0·0001), the mean percent predicted FEV 1 increased by 11·2 percentage points (95% CI 9·8 to 12·6) in the elexacaftor plus tezacaftor plus ivacaftor group and by 1·0 percentage points (-0·4 to 2·4) in the tezacaftor plus ivacaftor group (least squares mean treatment difference 10·2 percentage points [8·2 to 12·1], p<0·0001), and the mean sweat chloride concentration decreased by 46·2 mmol/L (95% CI 43·7 to 48·7) in the elexacaftor plus tezacaftor plus ivacaftor group and by 3·4 mmol/L (1·0 to 5·8) in the tezacaftor plus ivacaftor group (least squares mean treatment difference -42·8 mmol/L [-46·2 to -39·3], nominal p<0·0001). Most participants (70 [80%] in the elexacaftor plus tezacaftor plus ivacaftor group and 74 [84%] in the tezacaftor plus ivacaftor group) had adverse events that were mild or moderate in severity; serious adverse events occurred in five (6%) of 87 participants in the elexacaftor plus tezacaftor plus ivacaftor group and 14 (16%) of 88 participants in the tezacaftor plus ivacaftor group. One (1%) participant in the elexacaftor plus tezacaftor plus ivacaftor group discontinued treatment due to an adverse event of anxiety and depression. Two (2%) participants in the tezacaftor plus ivacaftor group discontinued treatment due to adverse events of psychotic disorder (n=1) and obsessive-compulsive disorder (n=1)., Interpretation: The elexacaftor plus tezacaftor plus ivacaftor regimen was safe and well tolerated, and led to significant and clinically meaningful improvements in respiratory-related quality of life and lung function, as well as improved CFTR function, changes that were durable over 24 weeks and superior to those seen with tezacaftor plus ivacaftor in this patient population., Funding: Vertex Pharmaceuticals., Competing Interests: Declaration of interests SS received personal fees from Proteostasis Therapeutics, Novartis Pharma, Vertex Pharmaceuticals, Chiesi, and Teva outside of the submitted work; and grants from Galapagos, Proteostasis Therapeutics, Celtaxsys, Flatley, Vertex Pharmaceuticals, Teva, Chiesi, Boehringer Ingelheim, Corbus Pharmaceuticals, and Ionis Pharmaceuticals outside of the submitted work. EFM received personal fees and grants from Vertex Pharmaceuticals during the conduct of the study; personal fees from Roche Pharmaceuticals, Insmed, and Janssen Pharmaceuticals; and other financial support from A Menarini outside of the submitted work. DGD received non-financial support from Vertex Pharmaceuticals during the conduct of the study; personal fees from Vertex Pharmaceuticals, Proteostasis, and Chiesi; and grants from Chiesi outside of the submitted work. JD received advisory board and speaker fees from Vertex Pharmaceuticals outside of the submitted work. EVB received institutional grants from Vertex Pharmaceuticals for the submitted work; and institutional grants from Vertex Pharmaceuticals, Galapagos, and Abbvie for other cystic fibrosis-related trials. MAM received personal fees from Vertex Pharmaceuticals during the conduct of the study; grants from Vertex Pharmaceuticals; and personal fees from Boehringer Ingelheim, Arrowhead Pharmaceuticals, Vertex Pharmaceuticals, Santhera, Galapagos, Sterna Biologicals, Enterprise Therapeutics, Kither Biotech, and Antabio outside of the submitted work. ET received grants and non-financial support from Vertex Pharmaceuticals during the conduct of the study; grants from Abbvie, Boehringer Ingelheim, Bayer, Spyryx, Horizon, Corbus, and Celtaxis; personal fees from Proteostasis and Horizon; and non-financial support from Proteostasis and Spyryx outside of the submitted work. CEW received institutional grants from Vertex Pharmaceuticals during the conduct of the study; grants from Novo Nordisk outside of the submitted work; and personal fees from Vertex Pharmaceuticals, Boehringer Ingelheim, Novartis, DKBmed, Gilead, and In Vivo Academy outside of the submitted work. DWal and SMM have pending patents for methods of treatment for cystic fibrosis, pharmaceutical compositions for treatment of cystic fibrosis, compositions and methods for treatment of cystic fibrosis, and crystalline forms and compositions of CFTR modulators. DWal and SMM have issued patents for crystalline forms and compositions of CFTR modulators. NA, BGB, CH, APL, YL, SMM, ST, JY, and DWal are employees of Vertex Pharmaceuticals and might own stock or stock options in the company. GM and DWat declare no competing interests., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Introduction: Breast Q questionnaire measures patient's perceptions following breast reconstruction using quality of life and satisfaction. This study assessed patient reported outcomes following mastectomy and reconstruction utilizing Breast Q., Methods: All consecutive Letterkenny Hospital patients undergoing mastectomy and breast reconstruction between August 2008 and February 2011 were invited to complete Breast Q evaluation of their care. Collected data included: age; presenting complaint, height, weight; type of operation. RUMM 2020 program evaluated satisfaction where 0 is very dissatisfied to 100 very satisfied., Results: 30/33 (91%) patients completed Breast Q; mean age 43 ± 11 (range 29-64); mean BMI 27.3 ± 5 (range 21.7-43.1). 27 patients were symptomatic, and 3 were image detected. 23 had a latissimus dorsi reconstruction, 11 of these with implant augmentation, 5 had a DIEP and 2 implant only reconstruction. The mean satisfaction score of 79.7 indicating good to excellent results. Post reconstructive outcomes were not statistically different from pre-operative perceptions in key areas such as satisfaction with breasts, psychosocial and sexual well-being., Conclusion: This study identified outcomes as good as if not superior to international averages with preservation of satisfaction with breast and psychosocial well-being. Breast Q could help form a template for national benchmarks in patients undergoing mastectomy and reconstruction., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Background: For cystic fibrosis (CF) patients there is a lack of good assays of disease activity and response to new therapeutic interventions, including gene therapy. Current measures of airways inflammation severity are insensitive or non-specific., Methods: Bronchoalveolar lavage fluid from 39 CF children and 38 respiratory disease controls was obtained at bronchoscopy and analysed by surface enhanced laser desorption ionisation time of flight (SELDI-TOF) mass spectrometry. Recognized proteins were assessed for CF disease specificity. Individual protein identification of specific peaks was performed., Results: 1277 proteins/peptides, >4 kDa, were detected using 12 different surfaces and binding conditions. 202 proteins/peptides were differentially expressed in the CF samples (p<0.001), 167 up-regulated and 35 down-regulated. The most discriminatory biomarker had a mass of 5.163 kDa. The most abundant, with a mass of 10.6 kDa, was identified as s100 A8 (calgranulin A)., Conclusions: The application of SELDI-TOF mass spectrometry allows evaluation of proteins in BAL fluid avoiding the limitations of only analysing predetermined proteins and potentially identifying proteins not previously appreciated as biomarkers. Its application to cystic fibrosis should enable appropriate evaluation of evolving illness, of gene therapy and other new therapies.

Type II Bartter's syndrome is a hereditary hypokalemic renal salt-wasting disorder caused by mutations in the ROMK channel (Kir1.1; Kcnj1), mediating potassium recycling in the thick ascending limb of Henle's loop (TAL) and potassium secretion in the distal tubule and cortical collecting duct (CCT). Newborns with Type II Bartter are transiently hyperkalemic, consistent with loss of ROMK channel function in potassium secretion in distal convoluted tubule and CCT. Yet, these infants rapidly develop persistent hypokalemia owing to increased renal potassium excretion mediated by unknown mechanisms. Here, we used free-flow micropuncture and stationary microperfusion of the late distal tubule to explore the mechanism of renal potassium wasting in the Romk-deficient, Type II Bartter's mouse. We show that potassium absorption in the loop of Henle is reduced in Romk-deficient mice and can account for a significant fraction of renal potassium loss. In addition, we show that iberiotoxin (IBTX)-sensitive, flow-stimulated maxi-K channels account for sustained potassium secretion in the late distal tubule, despite loss of ROMK function. IBTX-sensitive potassium secretion is also increased in high-potassium-adapted wild-type mice. Thus, renal potassium wasting in Type II Bartter is due to both reduced reabsorption in the TAL and K secretion by max-K channels in the late distal tubule.

Male mice deficient in BCLW, a death-protecting member of the BCL2 family, are sterile due to an arrest in spermatogenesis that is associated with a gradual loss of germ cells and Sertoli cells from the testis. As Bclw is expressed in both Sertoli cells and diploid male germ cells, it has been unclear which of these cell types requires BCLW in a cell-autonomous manner for survival. To determine whether death of Sertoli cells in Bclw mutants is influenced by the protracted loss of germ cells, we examined testes from Bclw/c-kit double mutant mice, which lack germ cells from birth. Loss of BCLW-deficient Sertoli cells occurs in the absence of germ cells, indicating that germ cell death is not required to mediate loss of Sertoli cells in BCLW-deficient mice. This suggests that Sertoli cells require BCLW in a cell-intrinsic manner for long-term survival. The loss of Sertoli cells in Bclw mutants commences shortly after Sertoli cells have become postmitotic. In situ hybridization analysis indicates that Bclw is expressed in Sertoli cells both before and after exit from mitosis. Therefore, Bclw-independent pathways promote the survival of undifferentiated, mitotic Sertoli cells. We show that BAX and BAK, two closely related death-promoting members of the BCL2 family, are expressed in Sertoli cells. To determine whether either BAX or BAK activity is required for Sertoli cell death in Bclw mutant animals, we analyzed survival of Sertoli cells in Bclw/Bax and Bclw/Bak double homozygous mutant mice. While mutation of Bak had no effect, ablation of Bax suppressed the loss of Sertoli cells in Bclw mutants. Thus, BCLW mediates survival of postmitotic Sertoli cells in the mouse by suppressing death-promoting activity of BAX., (Copyright 2001 Academic Press.)

Removal of fetal lung fluid at birth is crucial to survival. In vivo, a reversal in the direction of vectorial, amiloride-sensitive Na+) transport can be stimulated by ETYA, a nonmetabolizable analogue of the naturally occurring unsaturated fatty acid, arachidonate. Using the patch-clamp technique, fetal guinea pig alveolar type II pneumocyte single Na+ channel activity was robustly activated by 10 microM arachidonate, ETYA, oleate and stearate; this was unaffected by cyclooxygenase and 5'lipoxygenase inhibitors. The Na+ channel expressed in fetal guinea pig alveolar epithelial type II pneumocytes has biophysical properties compatible with species-specific coexpression of a novel variant of alphaENaC with betaENaC. gammaENaC is either not expressed in this tissue or shares very little homology with the rat and human gamma subunit. Thus, dramatic stimulation of this channel by arachidonate explains the in vivo observation of gestation-dependent reversal of fetal transepithelial driving force and may, therefore, be of physiological significance during the transition to breathing air at birth., (Copyright 2001 Academic Press.)

Biophysical properties of ROMK2 channel were investigated at physiological temperature, after reexpression of the recombinant ROMK2 protein in a mammalian cell expression system (COS-7). We observed that ROMK2 induced an inwardly rectifying K(+) current whether polyvalent cations were present or not. Above +10 mV, ROMK2-induced current exhibited a voltage- and time-dependent decay, consistent with an inactivation process. Inactivation of ROMK2-induced current was also seen in inside out patch from ROMK2-expressing Xenopus oocyte. In COS-7 cells, inactivation was found to account for most of the inward rectification. Mg(2+) and spermine modulated rectification by accelerating inactivation kinetics independently of membrane potential. These results establish for the first time ROMK2 properties in a mammalian cell expression system., (Copyright 2001 Academic Press.)

Background: We evaluated the prevalence of left ventricular hypertrophy in elite footballers compared with sedentary controls. A total of 141 elite male professional footballers and 32 healthy sedentary controls were studied. Echocardiographic and demographic variables were compared between groups by unpaired t-test., Results: The prevalence of left ventricular hypertrophy with maximal wall thickness values out with the normal range (>12 mm) was noted. Footballers were significantly younger than controls (20.9 vs. 24.3 years, P<0.005: 95% CI (-5.2, -1.73)) but there were no significant differences in height, weight or body surface area between the groups. Each of inter-ventricular septum (10.4 vs. 9.1 mm, P<0.0001; 95% CI (0.88, 1.72)), posterior wall (9.2 vs. 8.5 mm, P<0.01; 95% CI (0.22, 1.21)), left ventricular cavity (systolic and diastolic) (34.5 vs. 28.4 mm, P<0.0001; 95% CI (4.31, 7.76) in systole; 50.1 vs. 48.2 mm, P<0.05; 95% CI (0.15, 3.74) in diastole), aortic root size (29.1 vs. 27.8 mm, P<0.05; 95% CI (0.03,2.49)) and left ventricular mass index (112 vs. 89 g/m2, P<0.0001; 95% CI (14.4, 32.1)) were significantly greater in footballers than in controls. Absolute left ventricular wall thickness >12 mm was present in 17 footballers (12%) (range 13-15 mm) and in no controls., Conclusions: Elite professional footballers have increased cardiac dimensions compared with healthy controls. The prevalence of absolute wall thicknesses out with the normal range is relatively high.

Nutrition plays a very important role in regulating blood pressure. If we reverted to our evolutionary diet the problem of high blood pressure would disappear. However, this is unlikely and we, therefore, need to identify the most important factors in our diet that predispose to high blood pressure and, therefore, to vascular disease. Studies clearly demonstrate the very important role of our current intake of salt in our diet as being the major factor in regulating blood pressure in populations. Other dietary factors have also been identified as playing an important role, particularly potassium intake and fruit and vegetable consumption. A more healthy diet, that is a diet with much less salt and increased potassium through an increase in fruit and vegetable consumption, a reduction in fat intake with substitution of saturated by monounsaturated fat, a reduction in meat and dairy products with an increase in fish consumption will have large effects on blood pressure but, at the same time, will decrease other cardiovascular risk factors, particularly cholesterol and glucose intolerance. This healthier diet will reduce cardiovascular disease and is similar to the diet now being advocated for the prevention of some forms of cancer. Diet is by far the most important environmental factor determining our longevity and for those who wish to live longer, a change in diet as early in life as possible will have substantial effects.

Increased activity of sodium/hydrogen exchange provides a potentially important mechanism for the development of hypertension. The aims of this study were to compare platelet sodium/hydrogen exchanger activity and renal acid-base excretion in normotensives and hypertensives of Caucasian origin. Platelet intracellular pH (pHi) was measured using the fluorescent dye BCECF to monitor intracellular pH. Sodium/hydrogen exchanger activity was estimated from the recovery of pHi clamped to 6.25 with nigericin. Normotensives had supine blood pressures of < 140 and < 90 mmHg; those with essential hypertension had blood pressures > 150/95 mmHg with no known secondary cause. Measurements of platelet pHi and sodium/hydrogen exchanger activity were made on 26 normotensives (ten female, sixteen male) and 25 hypertensives (five female, twenty male). All subjects were on their usual dietary sodium intake. Statistical analysis was by two-way analysis of variance for gender and blood pressure status. Group values are expressed as means+/-SD and a P value of < 0.05 was taken as being statistically significant. There were no significant differences in platelet pHi between the normotensive (n = 26) and the hypertensive (n = 25) group: pHi 7.21+/-0.14 and 7.18+/-0.16, respectively. The pHi recovery after acidification was sodium-dependent and inhibited by N-hexamethylene amiloride. Comparison of kinetic constants showed no significant differences between the normotensive and the hypertensive groups: values for rate constants and initial velocities were 0.24+/-0.04 s(-1), 0.16+/-0.03 dpHi/s for the normotensives and 0.25+/-0.05 s(-1), 0.16+/-0.03 dpHi/s for the hypertensives, respectively; there were also no significant differences in proton fluxes. The inability to find raised platelet sodium/hydrogen exchanger in the hypertensives contrasts with previous observations using other methods for the measurement of this exchanger in platelets and this raises important methodological issues in the assessment of platelet sodium/hydrogen exchanger activity.

This study has examined the association between circulating atrial natriuretic peptide (ANP), plasma cyclic GMP and urinary cyclic GMP in relation to hypertension and reduced renal function in 30 normotensives, in 30 patients with essential hypertension and in 22 patients with stable dialysis-independent chronic renal failure (CRF). Plasma ANP was significantly raised (about two-three-fold) in the CRF group compared with the hypertensive and normal groups; plasma cyclic GMP was also significantly raised in the CRF group (median group values: 4.6, 5.8 and 11.0 pmol/ml, respectively, for the normal, hypertensive and CRF groups). There were no significant differences in urinary cyclic GMP between the normotensives and hypertensives but urinary cyclic GMP was significantly reduced in the patients with CRF (median group values: 407.1, 450.9 and 247.8 pmol/min for the normal, hypertensive and CRF groups, respectively, P < 0.001). In the subjects with CRF, the clearance of cyclic GMP was reduced in proportion to the clearance of creatinine, but there was no significant difference in the fractional excretion of cyclic GMP (median group values: 78.1% in the normal group, 78.9% in the hypertensive group and 70.2% in the CRF group). In all groups, there was no association between circulating ANP and urinary cyclic GMP: By contrast, there was a positive association between plasma ANP and plasma cyclic GMP (r = 0.39 P < 0.001) that was independent of blood pressure or renal function. These results demonstrate that while a substantial amount of urinary cyclic GMP originates from the glomerular filtrate, to some extent, raised plasma ANP also contributes to the circulating levels of cyclic GMP. However, plasma cyclic GMP cannot be taken as a direct substitute for plasma ANP.

Background: Liddle's syndrome is a rare inherited form of hypertension in which mutations of the epithelial sodium channel result in increased renal sodium reabsorption. Essential hypertension in black patients also shows clinical features of sodium retention so we screened black people for the T594M mutation, the most commonly identified sodium-channel mutation., Methods: In a case-control study, 206 hypertensive (mean age 48.0 [SD 11.8] years, men:women 80:126) and 142 normotensive (48.7 [7.4] years; 61:81) black people who lived in London, UK, were screened for T594M. Part of the last exon of the epithelial sodium-channel beta subunit from genomic DNA was amplified by PCR. The T594M variant was detected by single-strand conformational polymorphism analysis of PCR products and confirmed by DNA sequencing., Findings: 17 (8.3%) of 206 hypertensive participants compared with three (2.1%) of 142 normotensive participants possessed the T594M variant (odds ratio [OR]=4.17 [95% CI 1.12-18.25], p=0.029). A high proportion of participants with the T594M variant were women (15 of 17 hypertensive participants and all three normotensive participants), whereas women comprised a lower proportion of the individuals screened (61.2% hypertensive, 57.7% normotensive). However, the association between the T594M variant and hypertension persisted after adjustment for sex and body-mass index (Mantel-Haenszel OR=5.52 [1.40-30.61], p=0.012). Plasma renin activity was significantly lower in 13 hypertensive participants with the T594M variant (median=0.19 ng mL(-1) h(-1)) than in 39 untreated hypertensive individuals without the variant (median=0.45 ng mL(-1) h(-1), p=0.009)., Interpretation: Among black London people the T594M sodium-channel beta subunit mutation occurs more frequently in people with hypertension than those without. The T594M variant may increase sodium-channel activity and could raise blood pressure in affected people by increasing renal tubular sodium reabsorption. These findings suggest that the T594M mutation could be the most common secondary cause of essential hypertension in black people identified to date.

Background: Stroke is directly related to blood pressure and treatment trials in older hypertensive individuals show a reduction in strokes. However, the majority of strokes occur in normotensive individuals in whom no attempt is made to lower blood pressure. We compared the effects of modest salt restriction on blood pressure in older hypertensive and normotensive people., Methods: 47 untreated elderly people (24 men, age range 60-78 years; blood-pressure range 123-205 mm Hg systolic and 64-112 mm Hg diastolic) completed a 2-month double-blind randomised placebo-controlled crossover study of modest salt restriction with slow sodium and placebo to give a salt intake of either 10 g (equivalent to the normal amount for the UK population) or 5 g., Findings: On the normal salt intake for the UK population, supine blood pressure was 163/90 (SD 21/10) mm Hg with urinary sodium excretion of 177 (49) mmol/day. With modest sodium restriction, blood pressure fell to 156/87 (22/9) mm Hg (p < 0.001/0.004) with a urinary sodium excretion of 94 (50) mmol/day. A reduction in sodium intake of 83 mmol/day was associated with a reduction of 7.2/3.2 mm Hg. There was no significant difference in the blood-pressure fall between 18 normotensive and 29 hypertensive participants (8.2/3.9 vs 6.6/2.7 mm Hg)., Interpretation: A modest reduction in salt intake leads to a fall in blood pressure in both normotensive and hypertensive older people similar to that in outcome trials of thiazide-based treatment. Since the majority of strokes in older people occur below the current definition of hypertension, our results have important implications for the prevention of stroke.

Tissue nonspecific alkaline phosphatase (TNAP), the product of the Akp2 locus, is expressed in mouse primordial germ cells (PGC) for an extensive period during embryogenesis. Mice with the Akp2tm1Sor mutant allele of TNAP express lacZ (beta-galactosidase; beta-gal) under control of the Akp2 locus. PGCs were purified from Akp2tm1Sor embryos using fluorescence activated cell sorting of beta-gal expressing cells (FACS-gal). Analysis of the purified cells by alkaline phosphatase staining and immunocytochemistry with anti-c-kit antibody demonstrated that highly (98%) purified PGCs can be isolated using this method. This technique will facilitate experiments that require highly purified preparations of PGCs including cell culture and gene expression analyses.

Atherosclerotic renal artery disease is an important secondary cause of hypertension. Currently, there is great interest in possible genetic determinants of cardiovascular disease. The ACE-D allele has been reported to be associated with increased risk of myocardial infarction as well as coronary re-stenosis after angioplasty. We therefore assessed whether this allele is also linked to renovascular disease by studying 56 Caucasian subjects with atherosclerotic renal artery stenosis and 74 age, sex and race matched control subjects. Genetic analysis for the ACE I/D polymorphism was performed on peripheral leukocytes using PCR techniques, including insertion-specific primers. The distribution of I and D alleles was: renal artery stenosis 8 II, 25 ID, 23 DD; and controls, 16 II, 41 ID, 17 DD. The frequency of the D allele in the renal artery stenosis group was significantly higher (D/total 71/112 = 0.66) than that of the control population [75/148 = 0.51; chi 2 = 4.17, P = 0.04; odds ratio 1.69 (95% CI 1.02 to 2.78)]. Our results suggest that the ACE-D allele may be associated with increased risk of vascular disease at sites other than the coronary circulation.

A radioimmunoassay has been developed for measuring plasma neuropeptide-Y immunoreactivity using extraction on Sep-Pak C18 cartridges. Neuropeptide-Y concentrations (mean +/- SEM) in plasma from 15 normotensive individuals were 223.6 +/- 14.7 ng/l. Plasma concentrations were raised in 10 patients with heamodialysis-dependent chronic renal failure with values of 417.6 +/- 13.6 ng/l and in 3 patients with phaeochromocytoma the concentrations were 237 ng/l, 574 ng/l and 747 ng/l. Plasma neuropeptide-Y immunoreactivity was also measured in 10 normotensive individuals in response to a, hand-in-ice, cold pressor test. Despite an immediate significant elevation in blood pressure, neuropeptide-Y immunoreactivity was not significantly raised until after the removal of the hand from the ice by which time the blood pressure had returned towards the basal levels. This dissociation in neuropeptide-Y immunoreactivity and blood pressure responses probably reflects a delay in the diffusion of synaptic neuropeptide-Y into the general circulation. This study suggests that the measurement of neuropeptide-Y immunoreactivity may be a useful index of sympathetic activation.

Plasma levels of immunoreactive N-terminal ProANP have been measured in plasma from 19 healthy individuals, 15 patients with essential hypertension, 8 cardiac transplant recipients and 8 patients with chronic renal failure using two separate radioimmunoassays (RIAs), one directed against ProANP (1-30) and the other against ProANP (79-98). The mean concentrations of ProANP (1-30) and ProANP (79-98) were elevated in these groups of patients. There were positive correlations between levels of ProANP (1-30) and ProANP (79-98), with a correlation coefficient of 0.97 (P less than 0.001, n = 50). In healthy individuals a 2-1 (isotonic) saline infusion significantly increased both ANP (99-126) (P less than 0.05, n = 8) and N-terminal ProANP (P less than 0.005, n = 8) within 15 min of the end of the infusion. Plasma N-terminal ProANP levels were still significantly elevated after 75 min (P less than 0.05, n = 8) and 225 min (P less than 0.05, n = 8), by contrast ANP (99-126) had returned to basal values. Gel filtration of plasma extracted on Sep-Pak C-18 from normal individuals and patients gave a single immunoreactive peak for N-terminal ProANP as measured by both N-terminal ProANP assays, indicating an absence of small N-terminal fragments and the presence of a single high molecular weight form. These studies demonstrate that the major circulating N-terminal ANP in man is probably ProANP (1-98) and that it is cosecreted with ANP (99-126).

Diuretics are now commonly prescribed for women with so-called idiopathic oedema. Two patients with idiopathic oedema, one of whom was oedematous on diuretics, had the diuretics stopped. In one the oedema became much worse, and in the other oedema developed. However, this oedema disappeared spontaneously in both patients and they have remained free of oedema on no treatment. It is suggested that in some patients treated with diuretics compensatory mechanisms to retain sodium and water may be stronger than the diuretic-effect itself and may lead to perpetuation of unnecessary treatment.

A sensitive and specific procedure for the measurement of atrial natriuretic peptide (ANP) in human plasma by radioreceptor assay, using bovine adrenal membranes treated with Triton-X-100, is described. Plasma levels (mean +/- SEM) of ANP in healthy subjects on a normal sodium intake were 8.4 +/- 1.4 pg/ml and could be modified by changes in sodium intake with increases in sodium intake being associated with higher levels. Mean plasma ANP was approximately 2-fold higher in patients with essential hypertension and 4-fold higher in patients with cardiac or renal disease. The values obtained were comparable in magnitude to those obtained by radioimmunoassay and there was a strong correlation (r = 0.94; p less than 0.001) between the values obtained by radioimmuno- and radioreceptor-assay. These results suggest that circulating ANP corresponds to the biologically active peptide and point to an important role of the atrial peptides in the control of sodium balance.

20 patients with mild hypertension (average supine blood pressure without treatment, 164/101 mm Hg) reduced their salt intake to 50 mmol (3 g) per day for a month. They then entered a 3 month double-blind randomised crossover study of three levels of sodium intake: 200, 100, and 50 mmol per day. Blood pressure was significantly reduced on the middle and lowest sodium intakes. The average fall in blood pressure from the highest to the lowest sodium intake was 16/9 mm Hg. Patients continued to restrict their sodium intake for a further year. In 16 of the 20 patients blood pressure remained well controlled with salt restriction alone. Supine blood pressure at 1 year was 142/87 (SE 3/2) mm Hg with a 24 h urinary sodium excretion of 54 (7) mmol. These results show a progressive blood pressure fall as salt intake is reduced and that, in many patients with mild essential hypertension, blood pressure can be controlled without the need for drug therapy.