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Background: The introduction of large language models (LLMs) into clinical practice promises to improve patient education and empowerment, thereby personalizing medical care and broadening access to medical knowledge. Despite the popularity of LLMs, there is a significant gap in systematized information on their use in patient care. Therefore, this systematic review aims to synthesize current applications and limitations of LLMs in patient care., Methods: We systematically searched 5 databases for qualitative, quantitative, and mixed methods articles on LLMs in patient care published between 2022 and 2023. From 4349 initial records, 89 studies across 29 medical specialties were included. Quality assessment was performed using the Mixed Methods Appraisal Tool 2018. A data-driven convergent synthesis approach was applied for thematic syntheses of LLM applications and limitations using free line-by-line coding in Dedoose., Results: We show that most studies investigate Generative Pre-trained Transformers (GPT)-3.5 (53.2%, n = 66 of 124 different LLMs examined) and GPT-4 (26.6%, n = 33/124) in answering medical questions, followed by patient information generation, including medical text summarization or translation, and clinical documentation. Our analysis delineates two primary domains of LLM limitations: design and output. Design limitations include 6 second-order and 12 third-order codes, such as lack of medical domain optimization, data transparency, and accessibility issues, while output limitations include 9 second-order and 32 third-order codes, for example, non-reproducibility, non-comprehensiveness, incorrectness, unsafety, and bias., Conclusions: This review systematically maps LLM applications and limitations in patient care, providing a foundational framework and taxonomy for their implementation and evaluation in healthcare settings., Competing Interests: Competing interests: JNK declares consulting services for Owkin, France; DoMore Diagnostics, Norway; Panakeia, UK, and Scailyte, Basel, Switzerland; furthermore JNK holds shares in Kather Consulting, Dresden, Germany; and StratifAI GmbH, Dresden, Germany, and has received honoraria for lectures and advisory board participation by AstraZeneca, Bayer, Eisai, MSD, BMS, Roche, Pfizer and Fresenius. DT holds shares in StratifAI GmbH, Dresden, Germany and has received honoraria for lectures by Bayer. KKB reports grants from the European Union (101079894) and Wilhelm-Sander Foundation; participation on a Data Safety Monitoring Board or Advisory Board for the EU Horizon 2020 LifeChamps project (875329) and the EU IHI Project IMAGIO (101112053); speaker Fees for Canon Medical Systems Corporation and GE HealthCare. RK receives medical consultancy fees from Odin Vision. The remaining authors declare no competing interests., (© 2025. The Author(s).)

Gasotransmitters play crucial roles in regulating many physiological processes, including cell signaling, cellular proliferation, angiogenesis, mitochondrial function, antioxidant production, nervous system functions and immune responses. Hydrogen sulfide (H 2 S) is the most recently identified gasotransmitter, which is characterized by its biphasic behavior. At low concentrations, H 2 S promotes cellular bioenergetics, whereas at high concentrations, it can exert cytotoxic effects. Cystathionine β-synthetase (CBS), cystathionine-γ-lyase (CSE), 3-mercaptopyruvate sulfurtransferase (3-MST), and cysteinyl-tRNA synthetase 2 (CARS2) are pivotal players in H 2 S biosynthesis in mammalian cells and tissues. The focus of this review is the regulation of the various pathways involved in H 2 S metabolism in various forms of cancer. Key enzymes in this process include the sulfide oxidation unit (SOU), which includes sulfide:quinone oxidoreductase (SQOR), human ethylmalonic encephalopathy protein 1 (hETHE1), rhodanese, sulfite oxidase (SUOX/SO), and cytochrome c oxidase (CcO) enzymes. Furthermore, the potential role of H 2 S methylation processes mediated by thiol S-methyltransferase (TMT) and thioether S-methyltransferase (TEMT) is outlined in cancer biology, with potential opportunities for targeting them for clinical translation. In order to understand the role of H 2 S in oncogenesis and tumor progression, one must appreciate the intricate interplay between H 2 S-synthesizing and H 2 S-catabolizing enzymes.

Background & Aims: In 2018, the World Endoscopy Organization (WEO) introduced standardized methods for calculating post-colonoscopy colorectal cancer-3yr rates (PCCRC-3yr). This systematic review aimed to calculate the global PCCRC-3yr according to the WEO methodology, its change over time, and to measure the association between risk factors and PCCRC occurrences., Methods: We searched 5 databases from inception until January 2024 for PCCRC-3yr studies that strictly adhered to the WEO methodology. The overall pooled PCCRC-3yr was calculated. For risk factors and time-trend analyses, the pooled PCCRC-3yr and odds ratios (ORs) of subgroups were compared., Results: Several studies failed to adhere to the WEO methodology. Eight studies from 4 Western European and 2 Northern American countries were included, totalling 220,106 detected-colorectal cancers (CRCs) and 18,148 PCCRCs between 2002 and 2017. The pooled Western World PCCRC-3yr was 7.5% (95% confidence interval [CI], 6.4%-8.7%). The PCCRC-3yr significantly (P < .05) decreased from 7.9% (95% CI, 6.6%-9.4%) in 2006 to 6.7% (95% CI, 6.1%-7.3%) in 2012 (OR, 0.79; 95% CI, 0.72-0.87). There were significantly higher rates for people with inflammatory bowel disease (PCCRC-3yr, 29.3%; OR, 6.17; 95% CI, 4.73-8.06), prior CRC (PCCRC-3yr, 29.8%; OR, 3.03; 95% CI, 1.34-4.72), proximal CRC (PCCRC-3yr, 8.6%; OR, 1.51; 95% CI, 1.41-1.61), diverticular disease (PCCRC 3-yr, 11.6%; OR, 1.74; 95% CI, 1.37-2.10), and female sex (PCCRC-3yr, 7.9%; OR, 1.15; 95% CI, 1.11-1.20)., Conclusion: According to the WEO methodology, the Western World PCCRC-3yr was 7.5%. Reassuringly, this has decreased over time, but further work is required to identify the reasons for PCCRCs, especially in higher-risk groups. We devised a WEO methodology checklist to increase its adoption and standardise the categorization of patients in future PCCRC-3yr studies., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Introduction: Hydrogen sulfide (H 2 S) has been recently scrutinized for its critical role in aggravating breast cancer (BC) tumorigenicity. Several cancers aberrantly express H 2 S synthesizing enzymes; Cystathionine-β-synthase (CBS) and cystathionine-γ-lyase (CSE). However, their levels and interdependence in BC require further studies., Objectives: Firstly, this study aimed to demonstrate a comparative expression profile of H 2 S synthesizing enzymes in BC vs normal tissue. Moreover, to investigate the reciprocal relationship between CBS and CSE and highlight the importance of dual targeting. Finally, to search for a valid dual repressor of the H 2 S synthesizing enzymes that could cease H 2 S production and reduce TNBC pathogenicity., Methods: Pairwise analysis of tumor vs. normal tissues of 40 BC patients was carried out. The TNBC cell line MDA-MB-231 was transfected with oligonucleotides to study the H 2 S mediated molecular mechanisms. In silico screening was performed to identify dual regulator(s) for CBS and CSE. Gene expression analysis was performed using qRT-PCR and was confirmed on protein level using Western blot. TNBC hallmarks were evaluated using MTT, migration, and clonogenicity assays. H 2 S levels were detected using a AzMc fluorescent probe., Results: BC tissues exhibited elevated levels of both CBS and CSE. Interestingly, upon CBS knockdown, CSE levels increased compensating for H 2 S production in TNBC cells, underlining the importance of dually targeting both enzymes in TNBC. In silico screening suggested miR-939-5p as a regulator of both CBS and CSE with high binding scores. Low expression levels of miR-939-5p were found in BC tissues, especially the aggressive subtypes. Ectopic expression of miR-939-5p significantly repressed CBS and CSE transcript and protein levels, diminished H 2 S production and attenuated TNBC hallmarks. Moreover, it improved the immune surveillance potency of TNBC cells through up regulating the NKG2D ligands, MICB and ULBP2 and reducing the immune suppressive cytokine IL-10., Conclusion: This study sheds light on the reciprocal relationship between CBS and CSE and on the importance of their dual targeting, particularly in TNBC. It also postulates miR-939-5p as a potent dual repressor for CBS and CSE overcoming their redundancy in H 2 S production, a mechanism that can potentially attenuate TNBC oncogenicity and improves the immunogenic response., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

Colorectal cancer is the third most common type of cancer with almost two million new cases worldwide. They develop from neoplastic polyps, most commonly adenomas, which can be removed during colonoscopy to prevent colorectal cancer from occurring. Unfortunately, up to a quarter of polyps are missed during colonoscopies. Studies have shown that polyp detection during a procedure correlates with the time spent searching for polyps, called the withdrawal time. The different phases of the procedure (cleaning, therapeutic, and exploration phases) make it difficult to precisely measure the withdrawal time, which should only include the exploration phase. Separating this from the other phases requires manual time measurement during the procedure which is rarely performed. In this study, we propose a method to automatically detect the cecum, which is the start of the withdrawal phase, and to classify the different phases of the colonoscopy, which allows precise estimation of the final withdrawal time. This is achieved using a Resnet for both detection and classification trained with two public datasets and a private dataset composed of 96 full procedures. Out of 19 testing procedures, 18 have their withdrawal time correctly estimated, with a mean error of 5.52 seconds per minute per procedure., Competing Interests: D.S: Odin Vision Ltd (I, S), D.S: Digital Surgery Ltd (E), L.L: Odin Vision Ltd (I)., (Published by Optica Publishing Group under the terms of the Creative Commons Attribution 4.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.)

Lynch syndrome (LS) is an inherited cancer predisposition syndrome associated with high lifetime risk of developing tumours, most notably colorectal and endometrial. It arises in the context of pathogenic germline variants in one of the mismatch repair genes, that are necessary to maintain genomic stability. LS remains underdiagnosed in the population despite national recommendations for empirical testing in all new colorectal and endometrial cancer cases. There are now well-established colorectal cancer surveillance programmes, but the high rate of interval cancers identified, coupled with a paucity of high-quality evidence for extra-colonic cancer surveillance, means there is still much that can be achieved in diagnosis, risk-stratification and management. The widespread adoption of preventative pharmacological measures is on the horizon and there are exciting advances in the role of immunotherapy and anti-cancer vaccines for treatment of these highly immunogenic LS-associated tumours. In this review, we explore the current landscape and future perspectives for the identification, risk stratification and optimised management of LS with a focus on the gastrointestinal system. We highlight the current guidelines on diagnosis, surveillance, prevention and treatment and link molecular disease mechanisms to clinical practice recommendations., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Williams, Hadjinicolaou, Norton, Kader and Lovat.)

Colonoscopy remains the gold standard investigation for colorectal cancer screening as it offers the opportunity to both detect and resect pre-cancerous polyps. Computer-aided polyp characterisation can determine which polyps need polypectomy and recent deep learning-based approaches have shown promising results as clinical decision support tools. Yet polyp appearance during a procedure can vary, making automatic predictions unstable. In this paper, we investigate the use of spatio-temporal information to improve the performance of lesions classification as adenoma or non-adenoma. Two methods are implemented showing an increase in performance and robustness during extensive experiments both on internal and openly available benchmark datasets., Competing Interests: D.S: Odin Vision Ltd (I, S), D.S: Digital Surgery Ltd (E), L.L: Odin Vision Ltd (I)., (Published by Optica Publishing Group under the terms of the Creative Commons Attribution 4.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.)

Background and Objectives : The objective of this study is to examine the effect of the BNT162b2 vaccine on systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and pulse pressure (PP) before and 15 min after two doses that were given 21 days apart. Materials and Methods : This active surveillance study of vaccine safety was conducted on 15 and 16 March (for the first dose) and 5 and 6 April (for the second dose) 2021 in an academic hospital. For both doses, SBP, DBP, MAP, and PP levels were measured before and 15 min after both doses were given to healthcare workers over the age of 18. The results of the study were based on measurements of the mean blood pressure (BP), the mean changes in BP, and the BP trends. Results : In total, 287 individuals received the vaccine. After the first dose, 25% ( n = 72) of individuals had a decrease in DBP of at least 10 mmHg (mean DBP decrease: 15 mmHg, 95% CI: 14-17 mmHg), and after the second dose it was 12.5% (mean DBP decrease: 13 mmHg, 95% CI: 12-15 mmHg). After the first dose, 28.6% ( n = 82) had a PP that was wider than 40 mmHg. After the first dose, 5.2% and 4.9% of the individuals experienced an increase or decrease in SBP, respectively, of more than 20 mmHg. After the second dose, the SBP of 11% ( n = 32) decreased by at least 20 mmHg. Conclusions : Improved understanding of vaccine effects on BP may help address vaccine hesitancy in healthcare workers.

Objective: The National Health Service (NHS) produces more carbon emissions than any public sector organisation in England. In 2020, it became the first health service worldwide to commit to becoming carbon net zero, the same year as the COVID-19 pandemic forced healthcare systems globally to rapidly adapt service delivery. As part of this, outpatient appointments became largely remote. Although the environmental benefit of this change may seem intuitive the impact on patient outcomes must remain a priority. Previous studies have evaluated the impact of telemedicine on emission reduction and patient outcomes but never before in the gastroenterology outpatient setting., Method: 2140 appointments from general gastroenterology clinics across 11 Trusts were retrospectively analysed prior to and during the pandemic. 100 consecutive appointments during two periods of time, from 1 June 2019 (prepandemic) to 1 June 2020 (during the pandemic), were used. Patients were telephoned to confirm the mode of transport used to attend their appointment and electronic patient records reviewed to assess did-not-attend (DNA) rates, 90-day admission rates and 90-day mortality rates., Results: Remote consultations greatly reduced the carbon emissions associated with each appointment. Although more patients DNA their remote consultations and doctors more frequently requested follow-up blood tests when reviewing patients face-to-face, there was no significant difference in patient 90-day admissions or mortality when consultations were remote., Conclusion: Teleconsultations can provide patients with a flexible and safe means of being reviewed in outpatient clinics while simultaneously having a major impact on the reduction of carbon emissions created by the NHS., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

The discovery that biomechanical forces regulate microbial virulence was established with the finding that physiological low fluid shear (LFS) forces altered gene expression, stress responses, and virulence of the enteric pathogen Salmonella enterica serovar Typhimurium during the log phase. These log phase LFS-induced phenotypes were independent of the master stress response regulator, RpoS (σ S ). Given the central importance of RpoS in regulating stationary-phase stress responses of S. Typhimurium cultured under conventional shake flask and static conditions, we examined its role in stationary-phase cultures grown under physiological LFS. We constructed an isogenic rpoS mutant derivative of wild-type S. Typhimurium and compared the ability of these strains to survive in vitro pathogenesis-related stresses that mimic those encountered in the infected host and environment. We also compared the ability of these strains to colonize (adhere, invade, and survive within) human intestinal epithelial cell cultures. Unexpectedly, LFS-induced resistance of stationary-phase S. Typhimurium cultures to acid and bile salts stresses did not rely on RpoS. Likewise, RpoS was dispensable for stationary-phase LFS cultures to adhere to and survive within intestinal epithelial cells. In contrast, the resistance of these cultures to challenges of oxidative and thermal stresses, and their invasion into intestinal epithelial cells was influenced by RpoS. These findings expand our mechanistic understanding of how physiological fluid shear forces modulate stationary-phase S. Typhimurium physiology in unexpected ways and provide clues into microbial mechanobiology and nuances of Salmonella responses to microenvironmental niches in the infected host. IMPORTANCE Bacterial pathogens respond dynamically to a variety of stresses in the infected host, including physical forces of fluid flow (fluid shear) across their surfaces. While pathogens experience wide fluctuations in fluid shear during infection, little is known about how these forces regulate microbial pathogenesis. This is especially important for stationary-phase bacterial growth, which is a critical period to understand microbial resistance, survival, and infection potential, and is regulated in many bacteria by the general stationary-phase stress response protein RpoS. Here, we showed that, unlike conventional culture conditions, several stationary-phase Salmonella pathogenic stress responses were not impacted by RpoS when bacteria were cultured under fluid shear conditions relevant to those encountered in the intestine of the infected host. These findings offer new insight into how physiological fluid shear forces encountered by Salmonella during infection might impact pathogenic responses in unexpected ways that are relevant to their disease-causing ability.

Background and Aims: Seattle protocol biopsies for Barrett's Esophagus (BE) surveillance are labour intensive with low compliance. Dysplasia detection rates vary, leading to missed lesions. This can potentially be offset with computer aided detection. We have developed convolutional neural networks (CNNs) to identify areas of dysplasia and where to target biopsy., Methods: 119 Videos were collected in high-definition white light and optical chromoendoscopy with i-scan (Pentax Hoya, Japan) imaging in patients with dysplastic and non-dysplastic BE (NDBE). We trained an indirectly supervised CNN to classify images as dysplastic/non-dysplastic using whole video annotations to minimise selection bias and maximise accuracy. The CNN was trained using 148,936 video frames (31 dysplastic patients, 31 NDBE, two normal esophagus), validated on 25,161 images from 11 patient videos and tested on 264 iscan-1 images from 28 dysplastic and 16 NDBE patients which included expert delineations. To localise targeted biopsies/delineations, a second directly supervised CNN was generated based on expert delineations of 94 dysplastic images from 30 patients. This was tested on 86 i-scan one images from 28 dysplastic patients., Findings: The indirectly supervised CNN achieved a per image sensitivity in the test set of 91%, specificity 79%, area under receiver operator curve of 93% to detect dysplasia. Per-lesion sensitivity was 100%. Mean assessment speed was 48 frames per second (fps). 97% of targeted biopsy predictions matched expert and histological assessment at 56 fps. The artificial intelligence system performed better than six endoscopists., Interpretation: Our CNNs classify and localise dysplastic Barrett's Esophagus potentially supporting endoscopists during surveillance., (© 2022 The Authors. United European Gastroenterology Journal published by Wiley Periodicals LLC on behalf of United European Gastroenterology.)

Background: The Baveno VI consensus identifies patients with compensated advanced chronic liver disease (cACLD) who can safely avoid screening endoscopy. However, concordance in clinical practice with this guidance is unknown. We audited clinical practice and the provision of transient elastography (TE) aiming to identify potential cost savings and benefits., Methods: Retrospective data collection from 12 sites across London over 6 months by reviewing oesophagogastroduodenoscopy (OGD) reports, platelet count and TE results as well as information on site-specific provision of TE., Results: Three-hundred and fifty-one screening procedures were identified; 177 (50.43%) had a TE test performed within the preceding 12 months; 142 (80.23%) patients with a recent TE test did not meet criteria for screening OGD. TE provision varied widely between sites., Conclusion: Improving concordance with the Baveno criteria through improved provision of TE would have benefits for patients, healthcare systems and the environment and would help to address the challenges of moving on from the COVID-19 pandemic., (© Royal College of Physicians 2022. All rights reserved.)

Background and Aims: With the potential integration of artificial intelligence (AI) into clinical practice, it is essential to understand end users' perception of this novel technology. The aim of this study, which was endorsed by the British Society of Gastroenterology (BSG), was to evaluate the UK gastroenterology and endoscopy communities' views on AI., Methods: An online survey was developed and disseminated to gastroenterologists and endoscopists across the UK., Results: One hundred four participants completed the survey. Quality improvement in endoscopy (97%) and better endoscopic diagnosis (92%) were perceived as the most beneficial applications of AI to clinical practice. The most significant challenges were accountability for incorrect diagnoses (85%) and potential bias of algorithms (82%). A lack of guidelines (92%) was identified as the greatest barrier to adopting AI in routine clinical practice. Participants identified real-time endoscopic image diagnosis (95%) as a research priority for AI, while the most perceived significant barriers to AI research were funding (82%) and the availability of annotated data (76%). Participants consider the priorities for the BSG AI Task Force to be identifying research priorities (96%), guidelines for adopting AI devices in clinical practice (93%) and supporting the delivery of multicentre clinical trials (91%)., Conclusion: This survey has identified views from the UK gastroenterology and endoscopy community regarding AI in clinical practice and research, and identified priorities for the newly formed BSG AI Task Force., Competing Interests: Competing interests: RK, RFB, OFA, NP, GC and SD declared no competing interests. MH received speaker fees from Cook Medical. DS is a shareholder in Odin Vision and Digital Surgery. LBL is a consultant and minor shareholder in Odin Vision. He has received research grants from Medtronic, Pentax Medical and DynamX; he is also on the advisory board for DynamX and Ninepoint Medical., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY. Published by BMJ.)

Oral administration of medications to children requires age-appropriate dosage forms and strengths. In this study, we: (i) assessed the extent of oral dosage form manipulations, (ii) documented how it is carried out, and (iii) examined the attitudes and sources of information regarding the handling from healthcare professionals. Prospective reviews of electronic records, ward observations, and clinician surveys were performed at a paediatric neurology ward and a paediatric oncology ward in Sweden during April to May of 2018. Approximately 15% of oral medications were manipulated for the studied patient group (median age 12.9 years in oncology, 5.8 years in neurology) with approximately 30% of the patients having an enteral feeding tube. Manipulations were performed both to obtain an appropriate dose from, for example, a fraction of the original tablet or to obtain a powder that could be used to prepare a slurry for administration through enteral feeding tubes. Risks identified were related to patient safety such as cross contamination, suboptimal absorption/pharmacokinetics and inaccurate dose. When examining the working environment of nurses, we observed safe handling of hazardous substances but the nurses occasionally experienced stress and a fear of making mistakes due to absence of information. Paediatricians experienced a lack of time to search for proper information on manipulations. As a step towards improving safety in paediatric medication, we suggest the introduction of clinical pharmacists into the team and further evaluating the possibilities of using more ready-to-administer medications with necessary product information and pharmacovigilance support.

Colonoscopy remains the gold standard investigation for colorectal cancer screening as it offers the opportunity to both detect and resect pre-malignant and neoplastic polyps. Although technologies for image-enhanced endoscopy are widely available, optical diagnosis has not been incorporated into routine clinical practice, mainly due to significant inter-operator variability. In recent years, there has been a growing number of studies demonstrating the potential of convolutional neural networks (CNN) to enhance optical diagnosis of polyps. Data suggest that the use of CNNs might mitigate the inter-operator variability amongst endoscopists, potentially enabling a "resect and discard" or "leave in" strategy to be adopted in real-time. This would have significant financial benefits for healthcare systems, avoid unnecessary polypectomies of non-neoplastic polyps and improve the efficiency of colonoscopy. Here, we review advances in CNN for the optical diagnosis of colorectal polyps, current limitations and future directions., Competing Interests: Conflict-of-interest statement: Rawen Kader is supported by the Wellcome/EPSRC Centre for Interventional and Surgical Sciences (WEISS) at UCL; [203145Z/16/Z]. Danail Stoyanov owns shares in Odin Vision and Digital Surgery Ltd. Laurence B Lovat owns shares in Odin Vision. The remaining authors declare no conflict of interest., (©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.)

(1) Background: Alveolar echinococcosis (AE) is restricted to the northern hemisphere with high endemic regions in Central Europe, North and Central Asia as well as Western China. The larval stage of Echinococcus multilocularis (E. multilocularis) causes AE with tumor-like growth. Humans are accidental hosts. This report is on the first case of AE becoming clinically manifested in the parotic gland. (2) Case presentation: A 52-year-old male patient presented with progressive and painful swelling of the right parotid gland persisting for one year. We performed a partial parotidectomy. The histological examination and immunohistological staining revealed larval stage of E. multilocularis . (3) Conclusion: E. multilocularis is known to infect animals and humans coincidentally, and leads to AE. It is one of the most life-threatening zoonoses in Europe. It typically manifests in the liver (50-77%), with further spreading to other organs being a rare phenomenon. Echinococcosis should be considered in the differential diagnosis of lesions of the parotid gland in endemic areas, but AE has not been described so far in the parotid gland as the sole manifestation and, therefore, impedes the correct diagnosis. A complete resection should be the aim, however, preservation of the facial nerve and adjuvant albendazole therapy is mandatory.

Contrast-enhanced echocardiography or cardiac magnetic resonance imaging is of value in the diagnosis of apical hypertrophic cardiomyopathy. Apical hypertrophic cardiomyopathy is rare in Caucasians, and gene negativity does not rule out the diagnosis. Risk stratification for sudden cardiac death and decisions about anticoagulation in cases with atrial fibrillation should be based on guidelines., Competing Interests: Dr Magnusson received an unrestricted research grant from Abbott and speakers fee from Alnylam, Bayer, Boehringer‐Ingelheim, Pfizer, and Novo Nordisk.

The objective of this study was to understand the impact of hazardous and harmful use of alcohol and/or other drugs on ARV adherence and disease progression among HIV patients. A cross-sectional study design was used. A total of 1503 patients attending HIV clinics in Cape Town, South Africa were screened for problematic substance use. A sub-sample of 607 patients (303 patients who screened positive for problematic substance use and 304 who did not) participated in this study. Hazardous or harmful alcohol use and problematic drug use predicted missing and stopping ARVs which, in turn, was associated with a decrease in CD4 counts and more rapid HIV-disease progression and poorer health outcomes in people living with HIV/AIDS (PLWHA). The findings of this study underscore the need for an integrated approach to managing substance-use disorders in PLWHA.

Background: A performance measurement system is planned for South African substance abuse treatment services. Provider-level barriers to implementing these systems have been identified in the United States, but little is known about the nature of these barriers in South Africa. This study explored the willingness of South African substance abuse treatment providers' to adopt a performance measurement system and perceived barriers to monitoring service quality that would need to be addressed during system development., Methods: Three focus group discussions were held with treatment providers from two of the nine provinces in South Africa. These providers represented the diverse spread of substance abuse treatment services available in the country. The final sample comprised 21 representatives from 12 treatment facilities: eight treatment centres in the Western Cape and four in KwaZulu-Natal. Content analysis was used to extract core themes from these discussions., Results: Participants identified barriers to the monitoring of service quality that included outdated modes of collecting data, personnel who were already burdened by paperwork, lack of time to collect data, and limited skills to analyse and interpret data. Participants recommended that developers engage with service providers in a participatory manner to ensure that service providers are invested in the proposed performance measurement system., Conclusion: Findings show that substance abuse treatment providers are willing to adopt a performance measurement system and highlight several barriers that need to be addressed during system development in order to enhance the likelihood that this system will be successfully implemented.

Live recombinant attenuated Salmonella vaccine (RASV) strains have great potential to induce protective immunity against Mycobacterium tuberculosis by delivering M. tuberculosis antigens. Recently, we reported that, in orally immunized mice, RASV strains delivering the M. tuberculosis early secreted antigenic target 6-kDa (ESAT-6) protein and culture filtrate protein 10 (CFP-10) antigens via the Salmonella type III secretion system (SopE amino-terminal region residues 1 to 80 with two copies of ESAT-6 and one copy of CFP-10 [SopE(Nt80)-E2C]) afforded protection against aerosol challenge with M. tuberculosis. Here, we constructed and evaluated an improved Salmonella vaccine against M. tuberculosis. We constructed translational fusions for the synthesis of two copies of ESAT-6 plus CFP-10 fused to the OmpC signal sequence (OmpC(SS)-E2C) and amino acids 44 to 338 of antigen 85A (Ag85A(294)) flanked by the signal sequence (SS) and C-terminal peptide (CT) of β-lactamase (Bla(SS)-Ag85A(294)-Bla(CT)) to enable delivery via the Salmonella type II secretion system. The genes expressing these proteins were cloned as an operon transcribed from P(trc) into isogenic Asd(+)/MurA(+) pYA3681 lysis vector derivatives with different replication origins (pBR, p15A, pSC101), resulting in pYA4890, pYA4891, and pYA4892 for SopE(Nt80)-E2C/Ag85A(294) synthesis and pYA4893 and pYA4894 for OmpC(SS)-E2C/Ag85A(294) synthesis. Mice orally immunized with the RASV χ11021 strain engineered to display regulated delayed lysis and regulated delayed antigen synthesis in vivo and harboring pYA4891, pYA4893, or pYA4894 elicited significantly greater humoral and cellular immune responses, and the RASV χ11021 strain afforded a greater degree of protection against M. tuberculosis aerosol challenge in mice than RASVs harboring any other Asd(+)/MurA(+) lysis plasmid and immunization with M. bovis BCG, demonstrating that RASV strains displaying regulated delayed lysis with delayed antigen synthesis resulted in highly immunogenic delivery vectors for oral vaccination against M. tuberculosis infection.

Tuberculosis remains a global health threat, and there is dire need to develop a vaccine that is safe and efficacious and confers long-lasting protection. In this study, we constructed recombinant attenuated Salmonella vaccine (RASV) strains with plasmids expressing fusion proteins consisting of the 80 amino-terminal amino acids of the type 3 secretion system effector SopE of Salmonella and the Mycobacterium tuberculosis antigens early secreted antigenic target 6-kDa (ESAT-6) protein and culture filtrate protein 10 (CFP-10). We demonstrated that the SopE-mycobacterial antigen fusion proteins were translocated into the cytoplasm of INT-407 cells in cell culture assays. Oral immunization of mice with RASV strains synthesizing SopE-ESAT-6-CFP-10 fusion proteins resulted in significant protection of the mice against aerosol challenge with M. tuberculosis H37Rv that was similar to the protection afforded by immunization with Mycobacterium bovis bacillus Calmette-Guérin (BCG) administered subcutaneously. In addition, oral immunization with the RASV strains specifying these mycobacterial antigens elicited production of significant antibody titers to ESAT-6 and production of ESAT-6- or CFP-10-specific gamma interferon (IFN-γ)-secreting and tumor necrosis factor alpha (TNF-α)-secreting splenocytes.

Background: The type III secretion system (TTSS) is an important virulence determinant of Gram-negative bacterial pathogens. It enables the injection of effector proteins into the cytosol of eukaryotic cells. These effectors ultimately manipulate the cellular functions of the infected organism. Salmonella enterica serovar Typhimurium encodes two virulence associated TTSSs encoded by the Salmonella Pathogenicity Islands (SPI) 1 and 2 that are required for the intestinal and systemic phases of the infection, respectively. However, recent studies suggest that the roles of these TTSSs are not restricted to these compartments. The regulation of TTSSs in Salmonella is very complex with several regulators operating to activate or to repress expression depending on the environmental conditions., Results: We performed a systematic analysis of the regulation of type III effectors during growth in vitro. We have tested the ability of seven regulatory genes to regulate ten effector genes. Each regulator was expressed in the absence of the other six to avoid cascade effects. Our results confirm and extend the previously reported regulation of TTSS1 and TTSS2 effectors by InvF-SicA and SsrB respectively., Conclusion: The set of strains constructed for this study can be used to quickly and systematically study the regulation of newly identified effector genes of Salmonella enterica. The approach we have used can also be applied to study complex regulatory cascades in other bacterial species.

Purpose: To determine whether keratocytes made fibroblastic in vitro by addition of fetal bovine serum to the medium regain the keratocyte phenotype after culture in serum-free medium., Methods: Collagenase-isolated keratocytes from bovine corneas were plated in DMEM/F-12 containing 1% horse plasma, to allow cell attachment, and then cultured until day 4 in either DMEM/F-12 alone, to retain the keratocyte phenotype, or in DMEM containing 10% fetal bovine serum, to cause the keratocytes to become fibroblastic. Medium for the fibroblastic cells was replaced on day 4 with serum-free medium, and cells were cultured until day 12. Cell phenotypes were determined on days 4 to 5 and 11 to 12 of culture as follows: (1) by the morphologic appearance on phase-contrast microscopy; (2) by the levels of aldehyde dehydrogenase in the cells, determined by SDS-PAGE and Coomassie blue staining; (3) by the relative synthesis of collagen types I and V, determined by (14)C-proline radiolabeling; (4) by pepsin digestion and analysis of collagen types by SDS-PAGE autoradiography; (5) by relative synthesis of cornea-specific proteoglycan core proteins determined by analysis of chondroitinase- or endo-beta-galactosidase-generated radiolabeled core proteins by SDS-PAGE autoradiography; and (6) by the relative synthesis of keratan sulfate and chondroitin sulfate determined by (35)SO(4) radiolabeling and measuring the sensitivity to endo-beta-galactosidase and chondroitinase ABC., Results: Keratocytes cultured in serum-free medium appeared dendritic and became fibroblastic in appearance when exposed to medium containing serum. Keratocytes and fibroblasts synthesized a similar proportion of collagen types I and V. However, compared with the keratocytes, the fibroblasts possessed no aldehyde dehydrogenase and synthesized significantly higher levels of decorin and significantly lower levels of prostaglandin D synthase (PGDS) and keratan sulfate. Subsequent culture of the fibroblasts in serum-free medium did not restore aldehyde dehydrogenase to keratocyte levels but did restore the cell morphology to a more dendritic appearance and returned the synthesis of decorin, PGDS, and keratan sulfate to keratocyte levels., Conclusions: The results of these studies indicate that primary cultures of keratocytes made fibroblastic by exposure to serum can return to their keratocyte phenotype in synthesizing extracellular matrix. These results also indicate that the differences in the organization of the collagenous matrix produced by keratocytes and fibroblasts may be related more to the different proteoglycan types than to the collagen types produced.