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Endolysins, proteins encoded by phages to lyse their hosts and release their progeny, have evolved to adapt to the structural features of each host. The endolysins from Staphylococcus-infecting phages typically feature complex architectures with two enzymatically active domains (EADs) and one cell wall-binding domain (CBD) belonging to the bacterial SH3 (SH3b) superfamily. This study focuses on three SH3b-like CBDs from representative staphylococcal phage endolysins (LysRODI, LysC1C and LysIPLA5) that were structurally and functionally characterized. While RODI_CBD and C1C_CBD were assigned to the well-known SH3_5 family, a new family, SH3b_T (PF24246), was identified using the CBD from LysIPLA5 as a model. GFP-fused CBDs were created to assess their differential binding to a collection of staphylococcal strains. IPLA5_CBD showed enhanced binding to Staphylococcus epidermidis, while RODI_CBD and C1C_CBD exhibited distinct binding profiles, with RODI_CBD targeting Staphylococcus aureus specifically and C1C_CBD displaying broad binding. Sequence comparisons suggested that a few differences in key amino acids could be responsible for the latter binding difference. The CBDs modulated the activity spectrum of synthetic EAD-CBD combinations in accordance with the previous binding profiles, but in a manner that was also dependent on the EAD present in the fusion protein. These results serve as a context for the diversity and versatility of SH3b domains in staphylococcal endolysins, providing insights on how (i) the CBDs from this superfamily have diverged to adapt to diverse bacterial ligands in spite of sharing a common fold; and (ii) the evolution of specificity relies on the EAD-CBD combination rather than solely the CBD.
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The phage lysin field has done nothing but grow in the last decades. As a result, many different research groups around the world are contributing to the field, often with certain methodological differences that pose a challenge to the interpretation and comparison of results. In this work, we present the case study of three Acinetobacter baumannii-targeting phage lysins (wild-type endolysin LysMK34 plus engineered lysins eLysMK34 and 1D10) plus one lysin with broad activity against Gram-positive bacteria (PlySs2) to provide exemplary evidence on the risks of generalization when using one of the most common lysin evaluation assays: the killing assay with resting cells. To that end, we performed killing assays with the aforementioned lysins using hypo-, iso- and hypertonic buffers plus human serum either as the reaction or the dilution medium in a systematic manner. Our findings stress the perils of creating hypotonic conditions or a hypotonic shock during a killing assay, suggesting that hypotonic buffers should be avoided as a test environment or as diluents before plating to avoid overestimation of the killing effect in the assayed conditions. As a conclusion, we suggest that the nature of both the incubation and the dilution buffers should be always clearly identified when reporting killing activity data, and that for experimental consistency the same incubation buffer should be used as a diluent for posterior serial dilution and plating unless explicitly required by the experimental design. In addition, the most appropriate buffer mimicking the final application must be chosen to obtain relevant results.
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Acinetobacter baumannii , Bacteriófagos , Bacteriófagos/química , Bacteriófagos/fisiología , Bacteriófagos/genética , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/virología , Concentración Osmolar , Viabilidad Microbiana/efectos de los fármacos , Tampones (Química) , Humanos , Proteínas Virales/genética , Proteínas Virales/metabolismo , Proteínas Virales/química , Endopeptidasas/metabolismo , Endopeptidasas/químicaRESUMEN
Sexual dysfunction (SD) has been associated with worse quality of life and higher disease activity in patients with rheumatic diseases, yet it is still not regularly addressed during routine rheumatologic evaluations. This study aimed to determine the prevalence of sexual dysfunction in patients with rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE) and evaluate their perception of their sexual health. We performed a retrospective study in an outpatient rheumatology clinic to evaluate patients over 18 years old with a diagnosis of RA or SLE through the Spanish version of the Arizona Sexual Experiences Scale (ASEX) and the Sexual Health Perception Survey (SHEPS), a questionnaire of 6 items designed in our clinic. Additionally, we applied the Functional Assessment of Chronic Illness Therapy - Fatigue (FACIT-F version 4) and the Hospital Anxiety and Depression Scale (HADS). A total of 567 patients were evaluated with SHEPS, most of whom were women with a median age of 50 years (IQR: 34) and a median disease duration of 5 years (IQR: 9). Through the ASEX, we found that 67% of the patients with RA and 60% of the patients with SLE experienced SD. Patients reported the level of sex drive, arousal, and the ability to achieve orgasms as the areas with the most difficulties. Most patients did not know their disease could affect their sexuality and had never addressed these issues with their rheumatologists, but almost all of them were willing to. Our findings highlight the importance of addressing sexual health issues regularly during rheumatologic evaluations.
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OBJECTIVE: Stress and trauma are psychosocial factors with an impact on the course of systemic lupus erythematosus (SLE). The influence of violence on SLE has not been entirely explored, even though women (including patients with rheumatic diseases) are a vulnerable population to any form of violence. This study aims to assess the prevalence and impact of intimate partner violence (IPV) on health-related quality of life in women with SLE. METHODS: An observational, cross-sectional, and analytical study was conducted at a rheumatology clinic of a university hospital from September 2022 and September 2023. We evaluated the presence of IPV in 85 women with SLE with the Hurt, Insulted, Threatened with Harm and Screamed at (HITS) questionnaire and the Index of Spouse Abuse (ISA), and quality of life with LupusQoL. RESULTS: The prevalence by HITS score of past-year IPV was 24.4% and of lifetime IPV was 36.5%. Past-year non-physical violence was present in 17.1% of patients by ISA, and 27.1% were victims in their lifetime. While in physical violence, 7.3% were victims in the previous year and 21.2% in their lifetime. The total quality of life and the emotional domain by LupusQoL were diminished in victims of past-year IPV, compared to those who weren't exposed (p = .018 and p = .036, respectively). Past-year HITS score correlated with the Physician Global Assessment (PGA) (rho = 0.301, p = .006), while lifetime HITS score correlated with PGA (rho = 0.329, p = .002) and SLEDAI-2K (rho = 0.277, p = .010). CONCLUSION: We found that one in four women suffered IPV in the previous year, and those who were exposed had diminished quality of life. Also, the severity of the abuse correlated with disease activity. Our findings emphasize the importance of comprehensive care for patients with SLE.
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Violencia de Pareja , Lupus Eritematoso Sistémico , Calidad de Vida , Humanos , Lupus Eritematoso Sistémico/psicología , Femenino , Estudios Transversales , Adulto , Persona de Mediana Edad , Violencia de Pareja/psicología , Violencia de Pareja/estadística & datos numéricos , Prevalencia , Encuestas y CuestionariosRESUMEN
Schizophrenia is a prototypical network disorder with widespread brain-morphological alterations, yet it remains unclear whether these distributed alterations robustly reflect the underlying network layout. We tested whether large-scale structural alterations in schizophrenia relate to normative structural and functional connectome architecture, and systematically evaluated robustness and generalizability of these network-level alterations. Leveraging anatomical MRI scans from 2439 adults with schizophrenia and 2867 healthy controls from 26 ENIGMA sites and normative data from the Human Connectome Project (n = 207), we evaluated structural alterations of schizophrenia against two network susceptibility models: (i) hub vulnerability, which examines associations between regional network centrality and magnitude of disease-related alterations; (ii) epicenter mapping, which identifies regions whose typical connectivity profile most closely resembles the disease-related morphological alterations. To assess generalizability and specificity, we contextualized the influence of site, disease stages, and individual clinical factors and compared network associations of schizophrenia with that found in affective disorders. Our findings show schizophrenia-related cortical thinning is spatially associated with functional and structural hubs, suggesting that highly interconnected regions are more vulnerable to morphological alterations. Predominantly temporo-paralimbic and frontal regions emerged as epicenters with connectivity profiles linked to schizophrenia's alteration patterns. Findings were robust across sites, disease stages, and related to individual symptoms. Moreover, transdiagnostic comparisons revealed overlapping epicenters in schizophrenia and bipolar, but not major depressive disorder, suggestive of a pathophysiological continuity within the schizophrenia-bipolar-spectrum. In sum, cortical alterations over the course of schizophrenia robustly follow brain network architecture, emphasizing marked hub susceptibility and temporo-frontal epicenters at both the level of the group and the individual. Subtle variations of epicenters across disease stages suggest interacting pathological processes, while associations with patient-specific symptoms support additional inter-individual variability of hub vulnerability and epicenters in schizophrenia. Our work outlines potential pathways to better understand macroscale structural alterations, and inter- individual variability in schizophrenia.
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INTRODUCTION: Regional gray matter (GM) alterations have been reported in early-onset psychosis (EOP, onset before age 18), but previous studies have yielded conflicting results, likely due to small sample sizes and the different brain regions examined. In this study, we conducted a whole brain voxel-based morphometry (VBM) analysis in a large sample of individuals with EOP, using the newly developed ENIGMA-VBM tool. METHODS: 15 independent cohorts from the ENIGMA-EOP working group participated in the study. The overall sample comprised T1-weighted MRI data from 482 individuals with EOP and 469 healthy controls. Each site performed the VBM analysis locally using the standardized ENIGMA-VBM tool. Statistical parametric T-maps were generated from each cohort and meta-analyzed to reveal voxel-wise differences between EOP and healthy controls as well as the individual-based association between GM volume and age of onset, chlorpromazine (CPZ) equivalent dose, and other clinical variables. RESULTS: Compared with healthy controls, individuals with EOP showed widespread lower GM volume encompassing most of the cortex, with the most marked effect in the left median cingulate (Hedges' g = 0.55, p = 0.001 corrected), as well as small clusters of lower white matter (WM), whereas no regional GM or WM volumes were higher in EOP. Lower GM volume in the cerebellum, thalamus and left inferior parietal gyrus was associated with older age of onset. Deficits in GM in the left inferior frontal gyrus, right insula, right precentral gyrus and right superior frontal gyrus were also associated with higher CPZ equivalent doses. CONCLUSION: EOP is associated with widespread reductions in cortical GM volume, while WM is affected to a smaller extent. GM volume alterations are associated with age of onset and CPZ equivalent dose but these effects are small compared to case-control differences. Mapping anatomical abnormalities in EOP may lead to a better understanding of the role of psychosis in brain development during childhood and adolescence.
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Edad de Inicio , Encéfalo , Sustancia Gris , Imagen por Resonancia Magnética , Trastornos Psicóticos , Sustancia Blanca , Humanos , Sustancia Gris/patología , Trastornos Psicóticos/patología , Trastornos Psicóticos/diagnóstico por imagen , Masculino , Femenino , Imagen por Resonancia Magnética/métodos , Sustancia Blanca/patología , Sustancia Blanca/diagnóstico por imagen , Adolescente , Adulto , Encéfalo/patología , Adulto Joven , Mapeo Encefálico/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Estudios de CohortesRESUMEN
BACKGROUND: A desire for hastened death is commonly expressed by cancer patients. Although efforts to define and explore this issue have been undertaken, no standardized approach exists to address these desires. CASE DESCRIPTION: Ms. J expressed a wish for accelerated death and subsequently experienced unexpected clinical decline resulting in a quick, natural death. Our team experienced a mixture of both emotional distress and awe after witnessing the pragmatic approach our patient had to her impending decline, that we felt was worthy of further exploration. CONCLUSION: Most clinicians lack formal training in communication, potentially making cases like Ms. J's highly distressing. Clinicians should feel comfortable addressing and potentially inquiring about patients' desire to hasten death. While our initial reaction might be to correct this desire, we propose reframing this expression as an opportunity to explore more about our patients.
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IMPORTANCE: Engineered lysins are considered as highly promising alternatives for antibiotics. Our previous screening study using VersaTile technology identified 1D10 as a possible lead compound with activity against Acinetobacter baumannii strains under elevated human serum concentrations. In this manuscript, we reveal an unexpected mode of action and exceptional thermoresistance for lysin 1D10. Our findings shed new light on the development of engineered lysins, providing valuable insights for future research in this field.
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Bacteriófagos , Humanos , Bacteriófagos/genética , Antibacterianos/farmacología , Bacterias GramnegativasRESUMEN
Carbohydrate intake restriction positively affects markers related to metabolic syndrome (MS). However, the effects of long-term carbohydrate-free diets (CFD) have yet to be studied. The main objective of this study was to report the effects on biochemical and morphometric parameters in a rat model of MS. Male Wistar rats were initially divided into two groups: the standard diet group (SD, n = 20); and the MS group (n = 30) fed a high-glucose diet. Ten animals from each group were sacrificed after 20 weeks on their respective diets to verify MS development. The remaining MS animals were divided into two subgroups: one continued with the MS diet (n = 10); and the other transitioned to a carbohydrate-free diet (MS + CFD group, n = 10) for 20 more weeks. At week 40, parameters, including glucose, insulin, lipid profile, ketone bodies, C-reactive protein (CRP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea, creatinine, liver and muscle glycogen, and serum, hepatic, renal, and pancreatic malondialdehyde (MDA) levels were assessed. Transitioning to CFD resulted in decreased caloric intake and body weight, with normalized parameters including MDA, insulin, lipid profile, ALT, liver glycogen, creatinine, and CRP levels. This shift effectively reversed the MS-induced alterations, except for glycemia and uremia, likely influenced by the diet's high protein content stimulating gluconeogenesis. This research underscores the potential benefits of long-term carbohydrate restriction in mitigating MS-related markers.
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Carriers of BRCA1 germline pathogenic variants are at substantially higher risk of developing breast and ovarian cancer than the general population. Accurate identification of at-risk individuals is crucial for risk stratification and the implementation of targeted preventive and therapeutic interventions. Despite significant progress in variant classification efforts, a sizable portion of reported BRCA1 variants remain as variants of uncertain clinical significance (VUSs). Variants leading to premature protein termination and loss of essential functional domains are typically classified as pathogenic. However, the impact of frameshift variants that result in an extended incorrect terminus is not clear. Using validated functional assays, we conducted a systematic functional assessment of 17 previously reported BRCA1 extended incorrect terminus variants (EITs) and concluded that 16 constitute loss-of-function variants. This suggests that most EITs are likely to be pathogenic. However, one variant, c.5578dup, displayed a protein expression level, affinity to known binding partners, and activity in transcription and homologous recombination assays comparable to the wild-type BRCA1 protein. Twenty-three additional carriers of c.5578dup were identified at a US clinical diagnostic lab and assessed using a family history likelihood model providing, in combination with the functional data, a likely benign interpretation. These results, consistent with family history data in the current study and available data from ClinVar, indicate that most, but not all, BRCA1 variants leading to an extended incorrect terminus constitute loss-of-function variants and underscore the need for comprehensive assessment of individual variants.
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Predisposición Genética a la Enfermedad , Neoplasias Ováricas , Femenino , Humanos , Proteína C , Proteína BRCA1/genética , Neoplasias Ováricas/epidemiología , Mutación de Línea Germinal/genéticaRESUMEN
Pelleting of lignocellulosic biomass to improve its transportation, storage and handling impacts subsequent processing and conversion. This work reports the role of high moisture pelleting in the enzymatic digestibility of corn stover prior to pretreatment, together with associated substrate characteristics. Pelleting increases the digestibility of unpretreated corn stover, from 8.2 to 15.5% glucan conversion, at 5% solid loading using 1 FPU Cellic® CTec2 per g solids. Compositional analysis indicates that loose and pelleted corn stover have similar non-dissolvable compositions, although their extractives are different. Enzymatic hydrolysis of corn stover after size reduction to normalize particle sizes and removal of extractives confirms that pelleting improves corn stover digestibility. Such differences may be explained by the decreased particle size, improved substrate accessibility, and hydrolysis of cross-linking structures induced by pelleting. These findings are useful for the development of processing schemes for sustainable and efficient use of lignocellulose.
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Celulasa , Zea mays , Zea mays/química , Celulasa/química , Hidrólisis , BiomasaRESUMEN
Left-right asymmetry is an important organizing feature of the healthy brain that may be altered in schizophrenia, but most studies have used relatively small samples and heterogeneous approaches, resulting in equivocal findings. We carried out the largest case-control study of structural brain asymmetries in schizophrenia, with MRI data from 5,080 affected individuals and 6,015 controls across 46 datasets, using a single image analysis protocol. Asymmetry indexes were calculated for global and regional cortical thickness, surface area, and subcortical volume measures. Differences of asymmetry were calculated between affected individuals and controls per dataset, and effect sizes were meta-analyzed across datasets. Small average case-control differences were observed for thickness asymmetries of the rostral anterior cingulate and the middle temporal gyrus, both driven by thinner left-hemispheric cortices in schizophrenia. Analyses of these asymmetries with respect to the use of antipsychotic medication and other clinical variables did not show any significant associations. Assessment of age- and sex-specific effects revealed a stronger average leftward asymmetry of pallidum volume between older cases and controls. Case-control differences in a multivariate context were assessed in a subset of the data (N = 2,029), which revealed that 7% of the variance across all structural asymmetries was explained by case-control status. Subtle case-control differences of brain macrostructural asymmetry may reflect differences at the molecular, cytoarchitectonic, or circuit levels that have functional relevance for the disorder. Reduced left middle temporal cortical thickness is consistent with altered left-hemisphere language network organization in schizophrenia.
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Esquizofrenia , Masculino , Femenino , Humanos , Esquizofrenia/diagnóstico por imagen , Estudios de Casos y Controles , Encéfalo/diagnóstico por imagen , Corteza Cerebral , Imagen por Resonancia Magnética/métodos , Lateralidad FuncionalRESUMEN
Emerging evidence suggests brain white matter alterations in adolescents with early-onset psychosis (EOP; age of onset <18 years). However, as neuroimaging methods vary and sample sizes are modest, results remain inconclusive. Using harmonized data processing protocols and a mega-analytic approach, we compared white matter microstructure in EOP and healthy controls using diffusion tensor imaging (DTI). Our sample included 321 adolescents with EOP (median age = 16.6 years, interquartile range (IQR) = 2.14, 46.4% females) and 265 adolescent healthy controls (median age = 16.2 years, IQR = 2.43, 57.7% females) pooled from nine sites. All sites extracted mean fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD) for 25 white matter regions of interest per participant. ComBat harmonization was performed for all DTI measures to adjust for scanner differences. Multiple linear regression models were fitted to investigate case-control differences and associations with clinical variables in regional DTI measures. We found widespread lower FA in EOP compared to healthy controls, with the largest effect sizes in the superior longitudinal fasciculus (Cohen's d = 0.37), posterior corona radiata (d = 0.32), and superior fronto-occipital fasciculus (d = 0.31). We also found widespread higher RD and more localized higher MD and AD. We detected significant effects of diagnostic subgroup, sex, and duration of illness, but not medication status. Using the largest EOP DTI sample to date, our findings suggest a profile of widespread white matter microstructure alterations in adolescents with EOP, most prominently in male individuals with early-onset schizophrenia and individuals with a shorter duration of illness.
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Trastornos Psicóticos , Esquizofrenia , Sustancia Blanca , Femenino , Humanos , Masculino , Adolescente , Imagen de Difusión Tensora/métodos , Encéfalo , Esquizofrenia/tratamiento farmacológico , AnisotropíaRESUMEN
Biological therapies are available for the treatment of the severe allergic asthma (SAA) with blood eosinophil count ≥ 0.3 × 109/L. Several of them also showed benefits on nasal polyps (NP), one of the most frequent comorbidities of the severe asthma, but comparative studies on their effectiveness in the association SAA-NP are currently lacking. The aim of this study is to compare the effectiveness of benralizumab, mepolizumab and omalizumab in patients with SAA-NP in real-life settings. A retrospective, observational, multicenter real-life study was realized including patients with SAA-NP treated by benralizumab, mepolizumab or omalizumab for 6 months. We analysed the nasal and respiratory symptoms, the number of asthma attacks and salbutamol use/week, acute sinusitis and severe exacerbation rates, the asthma control score, the lung function parameters, the NP endoscopic score, the sinus imaging and the blood eosinophil count 6 months before and after treatment. Seventy-two patients with SAA-NP were included: 16 treated by benralizumab, 21 by mepolizumab and 35 by omalizumab. After 6 months of treatment, almost all studied parameters were improved (except sinus imaging) with a greater effect of omalizumab on the nasal pruritus (p = 0.001) and more benefits of benralizumab on exacerbations rate, asthma attacks per week and lung function (all p < 0.05). Benralizumab and mepolizumab were more effective to improve the NP endoscopic score and the blood eosinophil count (both p < 0.001). All three biological therapies showed effectiveness by improving asthma and nasal outcomes in patients with SAA-NP. Several differences have been found that should be confirmed by larger comparative studies.
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Antiasmáticos , Anticuerpos Monoclonales Humanizados , Asma , Pólipos Nasales , Humanos , Antiasmáticos/uso terapéutico , Asma/complicaciones , Asma/tratamiento farmacológico , Pólipos Nasales/complicaciones , Pólipos Nasales/tratamiento farmacológico , Omalizumab/uso terapéutico , Estudios Retrospectivos , Anticuerpos Monoclonales Humanizados/uso terapéuticoRESUMEN
The silent pandemic of antibiotic resistance is thriving, prompting the urgent need for the development of new antibacterial drugs. However, within the preclinical pipeline, in vitro screening conditions can differ significantly from the final in vivo settings. To bridge the gap between in vitro and in vivo assays, we developed a pig-skin-based bioluminescent ex vivo burn wound infection model, enabling real-time assessment of antibacterials in a longitudinal, non-destructive manner. We provide a proof-of-concept for A. baumannii NCTC13423, a multidrug-resistant clinical isolate, which was equipped with the luxCDABE operon as a reporter using a Tn7-based tagging system. This bioluminescence model provided a linear correlation between the number of bacteria and a broad dynamic range (104 to 109 CFU). This longitudinal model was subsequently validated using a fast-acting enzybiotic, 1D10. Since this model combines a realistic, clinically relevant yet strictly controlled environment with real-time measurement of bacterial burden, we put forward this ex vivo model as a valuable tool to assess the preclinical potential of novel phage-inspired enzybiotics.