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Coxiella burnetii is a globally distributed obligate intracellular pathogen. Although often asymptomatic, infections can cause acute Q fever with influenza-like symptoms and/or severe chronic Q fever. C. burnetii develops a unique replicative niche within host cells called the Coxiella-containing vacuole (CCV), facilitated by the Dot/Icm type IV secretion system translocating a cohort of bacterial effector proteins into the host. The role of some effectors has been elucidated; however, the actions of the majority remain enigmatic and the list of true effectors is disputable. This study examined CBU2016, a unique C. burnetii protein previously designated as an effector with a role in infection. We were unable to validate CBU2016 as a translocated effector protein. Employing targeted knock-out and complemented strains, we found that the loss of CBU2016 did not cause a replication defect within Hela, THP-1, J774, or iBMDM cells or in axenic media, nor did it affect the pathogenicity of C. burnetii in the Galleria mellonella infection model. Absence of CBU2016 did, however, result in a consistent decrease in the size of CCVs in HeLa cells. These results suggest that although CBU2016 may not be a Dot/Icm effector, it is still able to influence the host environment during infection.
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Maintaining cellular homeostasis in the face of stress conditions is vital for the overall well-being of an organism. Reactive oxygen species (ROS) are among the most potent cellular stressors and can disrupt the internal redox balance, giving rise to oxidative stress. Elevated levels of ROS can severely affect biomolecules and have been associated with a range of pathophysiological conditions. In response to oxidative stress, yeast activator protein-1 (Yap1p) undergoes post-translation modification that results in its nuclear accumulation. YAP1 has a key role in oxidative detoxification by promoting transcription of numerous antioxidant genes. In this study, we identified previously undescribed functions for NCE102, CDA2, and BCS1 in YAP1 expression in response to oxidative stress induced by hydrogen peroxide (H2O2). Deletion mutant strains for these candidates demonstrated increased sensitivity to H2O2. Our follow-up investigation linked the activity of these genes to YAP1 expression at the level of translation. Under oxidative stress, global cap-dependent translation is inhibited, prompting stress-responsive genes like YAP1 to employ alternative modes of translation. We provide evidence that NCE102, CDA2, and BCS1 contribute to cap-independent translation of YAP1 under oxidative stress.
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Phase four of the Alzheimer's Disease Neuroimaging Initiative (ADNI4) magnetic resonance imaging (MRI) protocols aim to maintain longitudinal consistency across two decades of data acquisition, while adopting new technologies. Here we describe and justify the study's design and targeted biomarkers. The ADNI4 MRI protocol includes nine MRI sequences. Some sequences require the latest hardware and software system upgrades and are continuously rolled out as they become available at each site. The main sequence additions/changes in ADNI4 are: (1) compressed sensing (CS) T1-weighting, (2) pseudo-continuous arterial spin labeling (ASL) on all three vendors (GE, Siemens, Philips), (3) multiple-post-labeling-delay ASL, (4) 1 mm3 isotropic 3D fluid-attenuated inversion recovery, and (5) CS 3D T2-weighted. ADNI4 aims to help the neuroimaging community extract valuable imaging biomarkers and provide a database to test the impact of advanced imaging strategies on diagnostic accuracy and disease sensitivity among individuals lying on the cognitively normal to impaired spectrum. HIGHLIGHTS: A summary of MRI protocols for phase four of the Alzheimer's Disease Neuroimaging Initiative (ADNI 4). The design and justification for the ADNI 4 MRI protocols. Compressed sensing and multi-band advances have been applied to improve scan time. ADNI4 protocols aim to streamline safety screening and therapy monitoring. The ADNI4 database will be a valuable test bed for academic research.
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Objectives: Patients with ankle fractures associated with diabetes experience more complications following standard open reduction-internal fixation (ORIF) than those without diabetes. Augmented fixation strategies, namely extended ORIF and hindfoot nails (HFNs), may offer better results and early weightbearing in this group. The aim of this study was to define the population of patients with diabetes undergoing primary fixation for ankle fractures. Secondarily, we aimed to assess the utilisation of standard and augmented strategies and the effect of these choices on surgical outcomes, including early post-operative weightbearing and surgical complications. Methods: A national multicentre retrospective cohort study was conducted between January and June 2019 in 56 centres (10 major trauma centres and 46 trauma units) in the United Kingdom; 1360 patients with specifically defined complex ankle fractures were enrolled. The patients' demographics, fixation choices and surgical and functional outcomes were recorded. Statistical analysis was performed to compare high-risk patients with and without diabetes. Results: There were 316 patients in the diabetes cohort with a mean age of 63.9 yrs (vs. 49.3 yrs. in the non-diabetes cohort), and a greater frailty score > 4 (24% vs. 14% (non-diabetes cohort) (p < 0.03)); 7.5% had documented neuropathy. In the diabetes cohort, 79.7% underwent standard ORIF, 7.1% extended ORIF and 10.2% an HFN, compared to 87.7%, 3.0% and 10.3% in the non-diabetes cohort. Surgical wound complications after standard-ORIF were higher in the diabetes cohort (15.1% vs. 8.7%) (p < 0.02), but patients with diabetes who underwent augmented techniques showed little difference in surgical outcomes/complications compared to non-diabetes patients, even though early-weightbearing rates were greater than for standard-ORIF. Conclusions: Ankle fractures in diabetes occur in older, frailer patients, whilst lower-than-expected neuropathy rates suggest a need for improved assessment. Augmented surgical techniques may allow earlier weightbearing without increasing complications, in keeping with modern guidelines in ankle fracture management.
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Background and Objectives: Despite numerous described techniques, laparoscopy has yet to replace open surgery as the gold standard for inguinal hernia (IH) repair in children. This may be due to many variables, including the lack of long-term follow-up and concern for increased recurrence. In this study, we present our long-term follow-up data on children undergoing percutaneous internal ring suturing (PIRS) for IH repair. Materials and Methods: This retrospective cohort study included children who underwent PIRS for IH between May 2013 and May 2021 at three tertiary care institutions, with at least three years of follow-up. Age at surgery, side of IH, presence of contralateral patent processus vaginalis, surgical and anesthesia time, and complications were noted. Parents were contacted to enquire about long-term complications, such as recurrence. Results: Long-term follow-up (average 6.9 ± 2.3 years) was available for 714 patients. For unilateral and bilateral procedures, the average surgical time was 13.6 ± 5.4 and 19.9 ± 3.0, and the average anesthesia time was 27.7 ± 12.9 and 33.9 ± 14.1 min, respectively. Complications were seen in 0.84% of patients and 1.2% of procedures, and recurrence was observed in 0.98% of patients and 0.78% of procedures. Conclusions: Our study, with a nearly 7-year follow-up, provides substantial evidence that PIRS is a safe and effective technique for IH repair in children, with low recurrence and complication rates. Despite the study's retrospective nature and limited sample size, it contributes valuable data supporting the use of PIRS in pediatric IH repair.
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Hernia Inguinal , Herniorrafia , Humanos , Hernia Inguinal/cirugía , Estudios Retrospectivos , Masculino , Femenino , Preescolar , Niño , Estudios de Seguimiento , Herniorrafia/métodos , Herniorrafia/efectos adversos , Lactante , Técnicas de Sutura , Resultado del Tratamiento , Estudios de Cohortes , Adolescente , Laparoscopía/métodos , RecurrenciaRESUMEN
Emerging evidence indicates that micro- and macro-plastics present in water can support a diverse microbial community, including potential human pathogens (e.g., bacteria, viruses). This interaction raises important concerns surrounding the role and suitability of current bathing water regulations and associated pathogen exposure risk within beach environments. In response to this, we critically evaluated the available evidence on plastic-pathogen interactions and identified major gaps in knowledge. This review highlighted the need for a conceptual shift in risk management at public beaches recognising: (i) interconnected environmental risks, e.g., associations between microbial compliance parameters, potential pathogens and both contemporary and legacy plastic pollution; and (ii) an appreciation of risk of exposure to plastic co-pollutants for both water and waterside users. We present a decision-making framework to identify options to manage plastic-associated pathogen risks alongside short- and longer-term research priorities. This advance will help deliver improvements in managing plastic-associated pathogen risk, acknowledging that human exposure potential is not limited to only those who engage in water-based activity. We argue that adopting these recommendations will help create an integrated approach to managing and reducing human exposure to pathogens at bathing, recreational water and beach environments.
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Playas , Plásticos , Gestión de Riesgos , Humanos , Microbiología del Agua , Contaminación del AguaRESUMEN
Background: People with HIV (PWH) who are coinfected with hepatitis B virus (HBV) have a higher risk of mortality compared with PWH alone. Populations such as people who inject drugs (PWID) and men who have sex with men (MSM) are particularly at high risk for HBV acquisition; yet, limited epidemiological data from these populations exist on HBV prevalence from low- and middle-income country settings (LMICs). Methods: We characterized the prevalence and correlates of HBV serological markers in a sample of PWID and MSM with HIV recruited across 15 Indian cities using hepatitis B surface antigen (HBsAg), hepatitis B core antibody (anti-HBc), and hepatitis B surface antibody (anti-HBs). Testing of stored specimens for the presence of these markers was performed on the Abbott ARCHITECT i1000 as per the manufacturer's instructions. Correlates of ever being infected with HBV (reactive for anti-HBc and/or HBsAg) and chronic HBV (reactive for HBsAg) among those ever infected were assessed using univariable and multivariable multilevel logistic regression models accounting for site-level clustering. Results: A total of 2198 (95%) of the 2314 participants recruited for the trial were screened for HBV markers. The median age among the PWID and MSM participants was 30 and 32 years, respectively. The prevalence of ever being infected with HBV was 75.6% vs 46.9% in PWID vs MSM, respectively (P < .01); prevalence of chronic infection was also higher in PWID vs MSM (14.1% vs 9.5%; P < .01). Correlates of ever being infected with HBV among PWID included unstable housing (adjusted odds ratio [aOR], 5.02) and sharing injection paraphernalia (aOR, 2.70), and among MSM, correlates included history of injection drug use (aOR, 4.87) and gender identity. The prevalence of isolated core (anti-HBc in the absence of anti-HBs) was 34.7% vs 29.4% in PWID vs MSM (P < .05). Vaccination serostatus was <10% in both populations. Conclusions: In this large sample of PWID and MSM with HIV, we observed a high prevalence of serology consistent with HBV infection and low vaccination, highlighting the need for routine screening and catch-up vaccination. The high prevalence of isolated anti-HBc reactivity highlights the need to understand the risk of reactivation with this serological pattern.
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Various tests based on different biomarkers have been developed to identify the best candidates for poly(ADP-ribose) polymerase (PARP)-inhibitor therapy. However, due to the absence of harmonization regarding these complex biomarkers, along with various cutoff points and unknown spatial and temporal variations, it is difficult to define the clinical utility of each test and ensure uniformity in treatment decision-making. Here, we propose measures to align biomarker definitions and minimum analytical performance characteristics for diagnostics to ensure equitable and sustainable access to precision medicine.
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Biomarcadores de Tumor , Desarrollo de Medicamentos , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Medicina de Precisión , Humanos , Desarrollo de Medicamentos/métodos , Medicina de Precisión/métodos , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Neoplasias/tratamiento farmacológicoRESUMEN
Axillary lymphadenitis in adults presents a diagnostic challenge due to its diverse etiology and variable clinical manifestations. We present a rare case of suppurative Group A Streptococcus (GAS) axillary lymphadenitis secondary to a puncture wound, emphasizing the critical importance of differential diagnosis and immediate intervention. A 36-year-old male initially presented with left axillary pain and discomfort following a traumatic injury to the left thumb. Despite multiple healthcare encounters and misdiagnoses including viral illness and shingles, the patient's condition deteriorated, manifesting as fever, edema, and erythema in the left axilla. This case underscores the paramount significance of considering lymphadenitis in patients with axillary symptoms, particularly following trauma or skin breaches. Early recognition and appropriate management are crucial to prevent grave complications such as abscess formation, thrombophlebitis, and bacteremia. Streptococcal axillary lymphadenitis should be included at the forefront of the differential diagnosis to expedite treatment and mitigate potential life-threatening consequences associated with delayed diagnosis.
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A novel method for quantifying the concentration of lactulose, rhamnose, xylose, and 3-O-methylglucose (3-OMG) in cat plasma using liquid chromatography-mass spectrometry (LC-MS) was developed. Domestic male cats (n = 13) were orally dosed with a solution containing the four sugars to test the permeability and absorptive capacity of their intestinal barrier. Plasma samples were taken 3 h later and were prepared with acetonitrile (ACN), dried under N2, and reconstituted in 90 % ACN with 1 mM ammonium formate. Stable isotope labelled 13C standards for each analyte were used as internal standards. Chromatographic separation was conducted using a Phenomenex Luna NH2 column with a gradient elution system of deionized water and 90 % ACN with 1 mM ammonium formate at 300 µL/min for 13 min total analysis time. Recovery trials were conducted in triplicate over three days with RSD values (%) for each day ranging from 1.2 to 1.4 for lactulose, 5.4 - 6.0 for rhamnose, 3.3 - 5.5 for xylose, and 2.6 - 5.6 for 3-OMG. Inter-day variations for each analyte were not different (p > 0.05). Limit of detection and quantification were 0.2 and 0.7 µg/mL for lactulose, 0.8 and 2.4 µg/mL for rhamnose, 0.6 and 1.8 µg/mL for xylose, and 0.3 and 1.1 µg/mL for 3-OMG, respectively. Plasma sugar concentrations recovered from cats were above the limit of quantification and below the highest calibration standard, validating the use of this method to test intestinal permeability and absorptive capacity in cats.
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Espectrometría de Masas en Tándem , Animales , Gatos , Espectrometría de Masas en Tándem/métodos , Masculino , Reproducibilidad de los Resultados , Cromatografía Liquida/métodos , Modelos Lineales , Intestino Delgado/metabolismo , Permeabilidad , Absorción Intestinal/fisiología , Límite de Detección , Administración Oral , Cromatografía Líquida con Espectrometría de Masas , Funcion de la Barrera IntestinalRESUMEN
Inpatient treatment of hyperkalaemia with insulin and dextrose can be complicated by iatrogenic hypoglycaemia. We sought to assess the incidence of hypoglycaemia in hospitalised patients with renal disease and assess the impact of the introduction of a local guideline incorporating the use of sodium zirconium cyclosilicate (SZC) for patients with moderate hyperkalaemia. After establishing a significant burden of hypoglycaemia in the initial observation period, a requirement for hourly capillary blood glucose monitoring (for up to 6 h) following the administration of insulin for hyperkalaemia was incorporated into the guidelines. The two-fold introduction of SZC alongside changes in patient care after the administration of insulin/dextrose resulted in more appropriate use of insulin/dextrose, as well as a significant (73%) reduction in the iatrogenic burden of hypoglycaemia (P = 0.04).
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Glucosa , Hiperpotasemia , Hipoglucemia , Insulina , Silicatos , Humanos , Hiperpotasemia/tratamiento farmacológico , Hiperpotasemia/inducido químicamente , Insulina/efectos adversos , Insulina/administración & dosificación , Insulina/uso terapéutico , Glucosa/uso terapéutico , Glucosa/administración & dosificación , Silicatos/uso terapéutico , Silicatos/efectos adversos , Hipoglucemia/tratamiento farmacológico , Hipoglucemia/inducido químicamente , Masculino , Femenino , Anciano , Glucemia/análisis , Glucemia/efectos de los fármacos , Persona de Mediana Edad , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/uso terapéutico , Hipoglucemiantes/administración & dosificación , Enfermedad Iatrogénica/prevención & controlRESUMEN
Introduction: Acute myeloid leukemia (AML) remains difficult to treat due to its heterogeneity in molecular landscape, epigenetics and cell signaling alterations. Precision medicine is a major goal in AML therapy towards developing agents that can be used to treat patients with different 'subtypes' in combination with current chemotherapies. We have previously developed dextrin-colistin conjugates to combat the rise in multi-drug resistant bacterial infections and overcome dose-limiting nephrotoxicity. Recent evidence of colistin's anticancer activity, mediated through inhibition of intracellular lysine-specific histone demethylase 1 (LSD1/KDM1A), suggests that dextrin-colistin conjugates could be used to treat cancer cells, including AML. This study aimed to evaluate whether dextrin conjugation (which reduces in vivo toxicity and prolongs plasma half-life) could enhance colistin's cytotoxic effects in myeloid leukemia cell lines and compare the intracellular uptake and localization of the free and conjugated antibiotic. Results: Our results identified a conjugate (containing 8000 g/mol dextrin with 1 mol% succinoylation) that caused significantly increased toxicity in myeloid leukemia cells, compared to free colistin. Dextrin conjugation altered the mechanism of cell death by colistin, from necrosis to caspase 3/7-dependent apoptosis. In contrast, conjugation via a reversible ester linker, instead of an amide, had no effect on the mechanism of the colistin-induced cell death. Live cell confocal microscopy of fluorescently labelled compounds showed both free and dextrin-conjugated colistins were endocytosed and co-localized in lysosomes, and increasing the degree of modification by succinoylation of dextrin significantly reduced colistin internalization. Discussion: Whilst clinical translation of dextrin-colistin conjugates for the treatment of AML is unlikely due to the potential to promote antimicrobial resistance (AMR) and the relatively high colistin concentrations required for anticancer activity, the ability to potentiate the effectiveness of an anticancer drug by polymer conjugation, while reducing side effects and improving biodistribution of the drug, is very attractive, and this approach warrants further investigation.
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Apoptosis , Colistina , Dextrinas , Colistina/farmacología , Colistina/química , Colistina/farmacocinética , Dextrinas/química , Dextrinas/farmacología , Humanos , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/farmacocinética , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/patología , Supervivencia Celular/efectos de los fármacosRESUMEN
Calmodulin transduces [Ca2+] information regulating the rhythmic Ca2+ cycling between the sarcoplasmic reticulum and cytoplasm during contraction and relaxation in cardiac and skeletal muscle. However, the structural dynamics by which calmodulin modulates the sarcoplasmic reticulum Ca2+ release channel, the ryanodine receptor, at physiologically relevant [Ca2+] is unknown. Using fluorescence lifetime FRET, we resolve different structural states of calmodulin and Ca2+-driven shifts in the conformation of calmodulin bound to ryanodine receptor. Skeletal and cardiac ryanodine receptor isoforms show different calmodulin-ryanodine receptor conformations, as well as binding and structural kinetics with 0.2-ms resolution, which reflect different functional roles of calmodulin. These FRET methods provide insight into the physiological calmodulin-ryanodine receptor structural states, revealing additional distinct structural states that complement cryo-EM models that are based on less physiological conditions. This technology will drive future studies on pathological calmodulin-ryanodine receptor interactions and dynamics with other important ryanodine receptor bound modulators.
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Calcio , Calmodulina , Transferencia Resonante de Energía de Fluorescencia , Músculo Esquelético , Miocardio , Canal Liberador de Calcio Receptor de Rianodina , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Canal Liberador de Calcio Receptor de Rianodina/química , Calmodulina/metabolismo , Calmodulina/química , Calcio/metabolismo , Miocardio/metabolismo , Cinética , Animales , Músculo Esquelético/metabolismo , Humanos , Conformación Proteica , Unión Proteica , Retículo Sarcoplasmático/metabolismoRESUMEN
Although many studies predict extensive future biodiversity loss and redistribution in the terrestrial realm, future changes in marine biodiversity remain relatively unexplored. In this work, we model global shifts in one of the most important marine functional groups-ecosystem-structuring macrophytes-and predict substantial end-of-century change. By modelling the future distribution of 207 brown macroalgae and seagrass species at high temporal and spatial resolution under different climate-change projections, we estimate that by 2100, local macrophyte diversity will decline by 3-4% on average, with 17 to 22% of localities losing at least 10% of their macrophyte species. The current range of macrophytes will be eroded by 5-6%, and highly suitable macrophyte habitat will be substantially reduced globally (78-96%). Global macrophyte habitat will shift among marine regions, with a high potential for expansion in polar regions.
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Biodiversidad , Cambio Climático , Ecosistema , Phaeophyceae , Algas Marinas , Algas Marinas/fisiologíaRESUMEN
Tumor mutation profiling (MP) is often conducted on tissue from biopsies conducted for clinical purposes (diagnostic tissue). We aimed to explore the views of patients with cancer on who should own tumor biopsy tissue, pay for its storage, and decide on its future use; and determine their attitudes to and predictors of undergoing additional biopsies if required for research purposes. In this mixed methods, cross-sectional study, patients with advanced solid cancers enrolled in the Molecular Screening and Therapeutics Program (nâ =â 397) completed a questionnaire prior to undergoing MP (nâ =â 356/397). A subset (nâ =â 23) also completed a qualitative interview. Fifty percent of participants believed they and/or relatives should own and control access to diagnostic tissue. Most (65.5%) believed the government should pay for tissue preparation. Qualitative themes included (1) custodianship of diagnostic tissue, (2) changing value of tissue across time and between cultures, (3) equity regarding payment, and (4) cost-benefit considerations in deciding on additional biopsies. Policy and regulation should consider patient perspectives. Extension of publicly funded health care to include tissue retrieval for clinical trials should be considered.
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NUDT15 homozygous mutations predispose patients to severe leucopenia, which invites risk of disseminated fungal infections when high doses or a combination of immunosuppressives are administered in this patient population.
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After recovery from a hepatitis B virus (HBV) infection, reactivation can occur with immunosuppression; thus, it is assumed that replication competent HBV persists in the liver. We sought to detect persistent HBV from 13 people with spontaneous recovery. We quantified HBV DNA and RNA in core liver biopsies (median 1.72x106 cells) from people who inject drugs (PWID). Among 13 biopsies, 8 (61%) had evidence of HBV DNA or RNA and 5 (38%) had both HBV DNA and RNA. mRNAs derived from cccDNA and integrated HBV DNA. Here, we show prevalent HBV DNA and RNA despite clinical recovery in PWID.
We used a sensitive method to determine the amount of hepatitis B virus DNA or RNA in the livers of 13 individuals who recovered from hepatitis B virus infection. We found viral DNA or RNA in the liver in 61% of individuals despite no detectable virus in blood. Our findings support that eliminating all hepatitis B from the liver is a difficult treatment goal.