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1.
Nature ; 624(7990): 130-137, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37993711

RESUMO

The termination of a meal is controlled by dedicated neural circuits in the caudal brainstem. A key challenge is to understand how these circuits transform the sensory signals generated during feeding into dynamic control of behaviour. The caudal nucleus of the solitary tract (cNTS) is the first site in the brain where many meal-related signals are sensed and integrated1-4, but how the cNTS processes ingestive feedback during behaviour is unknown. Here we describe how prolactin-releasing hormone (PRLH) and GCG neurons, two principal cNTS cell types that promote non-aversive satiety, are regulated during ingestion. PRLH neurons showed sustained activation by visceral feedback when nutrients were infused into the stomach, but these sustained responses were substantially reduced during oral consumption. Instead, PRLH neurons shifted to a phasic activity pattern that was time-locked to ingestion and linked to the taste of food. Optogenetic manipulations revealed that PRLH neurons control the duration of seconds-timescale feeding bursts, revealing a mechanism by which orosensory signals feed back to restrain the pace of ingestion. By contrast, GCG neurons were activated by mechanical feedback from the gut, tracked the amount of food consumed and promoted satiety that lasted for tens of minutes. These findings reveal that sequential negative feedback signals from the mouth and gut engage distinct circuits in the caudal brainstem, which in turn control elements of feeding behaviour operating on short and long timescales.


Assuntos
Regulação do Apetite , Tronco Encefálico , Ingestão de Alimentos , Retroalimentação Fisiológica , Alimentos , Saciação , Estômago , Regulação do Apetite/fisiologia , Tronco Encefálico/citologia , Tronco Encefálico/fisiologia , Ingestão de Alimentos/fisiologia , Vias Neurais/citologia , Vias Neurais/fisiologia , Neurônios/metabolismo , Hormônio Liberador de Prolactina/metabolismo , Saciação/fisiologia , Núcleo Solitário/citologia , Núcleo Solitário/fisiologia , Estômago/fisiologia , Paladar/fisiologia , Fatores de Tempo , Animais , Camundongos
2.
N Engl J Med ; 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38804512

RESUMO

BACKGROUND: Minimal change disease and primary focal segmental glomerulosclerosis in adults, along with idiopathic nephrotic syndrome in children, are immune-mediated podocytopathies that lead to nephrotic syndrome. Autoantibodies targeting nephrin have been found in patients with minimal change disease, but their clinical and pathophysiological roles are unclear. METHODS: We conducted a multicenter study to analyze antinephrin autoantibodies in adults with glomerular diseases, including minimal change disease, focal segmental glomerulosclerosis, membranous nephropathy, IgA nephropathy, antineutrophil cytoplasmic antibody-associated glomerulonephritis, and lupus nephritis, as well as in children with idiopathic nephrotic syndrome and in controls. We also created an experimental mouse model through active immunization with recombinant murine nephrin. RESULTS: The study included 539 patients (357 adults and 182 children) and 117 controls. Among the adults, antinephrin autoantibodies were found in 46 of the 105 patients (44%) with minimal change disease, 7 of 74 (9%) with primary focal segmental glomerulosclerosis, and only in rare cases among the patients with other conditions. Of the 182 children with idiopathic nephrotic syndrome, 94 (52%) had detectable antinephrin autoantibodies. In the subgroup of patients with active minimal change disease or idiopathic nephrotic syndrome who were not receiving immunosuppressive treatment, the prevalence of antinephrin autoantibodies was as high as 69% and 90%, respectively. At study inclusion and during follow-up, antinephrin autoantibody levels were correlated with disease activity. Experimental immunization induced a nephrotic syndrome, a minimal change disease-like phenotype, IgG localization to the podocyte slit diaphragm, nephrin phosphorylation, and severe cytoskeletal changes in mice. CONCLUSIONS: In this study, circulating antinephrin autoantibodies were common in patients with minimal change disease or idiopathic nephrotic syndrome and appeared to be markers of disease activity. Their binding at the slit diaphragm induced podocyte dysfunction and nephrotic syndrome, which highlights their pathophysiological significance. (Funded by Deutsche Forschungsgemeinschaft and others.).

3.
Proc Natl Acad Sci U S A ; 120(51): e2221680120, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38096407

RESUMO

Animals integrate sensory information from the environment and display various behaviors in response to external stimuli. In Caenorhabditis elegans hermaphrodites, 33 types of sensory neurons are responsible for chemosensation, olfaction, and mechanosensation. However, the functional roles of all sensory neurons have not been systematically studied due to the lack of facile genetic accessibility. A bipartite cGAL-UAS system has been previously developed to study tissue- or cell-specific functions in C. elegans. Here, we report a toolkit of new cGAL drivers that can facilitate the analysis of a vast majority of the 60 sensory neurons in C. elegans hermaphrodites. We generated 37 sensory neuronal cGAL drivers that drive cGAL expression by cell-specific regulatory sequences or intersection of two distinct regulatory regions with overlapping expression (split cGAL). Most cGAL-drivers exhibit expression in single types of cells. We also constructed 28 UAS effectors that allow expression of proteins to perturb or interrogate sensory neurons of choice. This cGAL-UAS sensory neuron toolkit provides a genetic platform to systematically study the functions of C. elegans sensory neurons.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Células Receptoras Sensoriais/metabolismo
4.
J Infect Dis ; 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38366561

RESUMO

BACKGROUND: Lysins (cell wall hydrolases) targeting Gram-negative organisms require engineering to permeabilize the outer membrane and access subjacent peptidoglycan to facilitate killing. In the current study, the potential clinical utility for engineered lysin, CF-370, was examined in vitro and in vivo against Gram-negative pathogens important in human infections. METHODS: MICs and bactericidal activity were determined using standard methods. An in vivo proof-of-concept efficacy study was conducted using a rabbit acute pneumonia model caused by Pseudomonas aeruginosa. RESULTS: CF-370 exhibited potent antimicrobial activity, with MIC50/90 values (in µg/mL) for: P. aeruginosa, 1/2; Acinetobacter baumannii, 1/1; Escherichia coli, 0.25/1; Klebsiella pneumoniae, 2/4; Enterobacter cloacae 1/4; and Stenotrophomonas maltophilia 2/8. CF-370 furthermore demonstrated: i) bactericidal activity; (ii) activity in serum; iii) a low propensity for resistance; iv) anti-biofilm activity; and v) synergy with antibiotics. In the pneumonia model, CF-370 alone decreased bacterial densities in lungs, kidneys and spleen vs. vehicle control, and demonstrated significantly increased efficacy when combined with meropenem (vs either agent alone). CONCLUSIONS: CF-370 is the first engineered lysin described with potent broad spectrum in vitro activity against multiple clinically-relevant Gram-negative pathogens, as well as potent in vivo efficacy in an animal model of severe invasive multi-system infection.

5.
Circulation ; 148(16): 1195-1206, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37634092

RESUMO

BACKGROUND: Intravascular imaging-guided percutaneous coronary intervention (PCI) with intravascular ultrasound (IVUS) or optical coherence tomography (OCT) showed superior clinical outcomes compared with angiography-guided PCI. However, the comparative effectiveness of OCT-guided and IVUS-guided PCI regarding clinical outcomes is unknown. METHODS: In this prospective, multicenter, open-label, pragmatic trial, we randomly assigned 2008 patients with significant coronary artery lesions undergoing PCI in a 1:1 ratio to undergo either an OCT-guided or IVUS-guided PCI. The primary end point was a composite of death from cardiac causes, target vessel-related myocardial infarction, or ischemia-driven target-vessel revascularization at 1 year, which was powered for noninferiority of the OCT group compared with the IVUS group. Safety outcomes were also assessed. RESULTS: At 1 year, primary end point events occurred in 25 of 1005 patients (Kaplan-Meier estimate, 2.5%) in the OCT group and in 31 of 1003 patients (Kaplan-Meier estimate, 3.1%) in the IVUS group (absolute difference, -0.6 percentage points; upper boundary of one-sided 97.5% CI, 0.97 percentage points; P<0.001 for noninferiority). The incidence of contrast-induced nephropathy was similar (14 patients [1.4%] in the OCT group versus 15 patients [1.5%] in the IVUS group; P=0.85). The incidence of major procedural complications was lower in the OCT group than in the IVUS group (22 [2.2%] versus 37 [3.7%]; P=0.047), although imaging procedure-related complications were not observed. CONCLUSIONS: In patients with significant coronary artery lesions, OCT-guided PCI was noninferior to IVUS-guided PCI with respect to the incidence of a composite of death from cardiac causes, target vessel-related myocardial infarction, or ischemia-driven target-vessel revascularization at 1 year. The selected study population and lower-than-expected event rates should be considered in interpreting the trial. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique number: NCT03394079.


Assuntos
Doença da Artéria Coronariana , Stents Farmacológicos , Infarto do Miocárdio , Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Angiografia Coronária/métodos , Tomografia de Coerência Óptica/métodos , Estudos Prospectivos , Stents Farmacológicos/efeitos adversos , Ultrassonografia de Intervenção/efeitos adversos , Ultrassonografia de Intervenção/métodos , Resultado do Tratamento , Infarto do Miocárdio/etiologia , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia
6.
Am Heart J ; 275: 86-95, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38723880

RESUMO

BACKGROUND: Artificial intelligence-based quantitative coronary angiography (AI-QCA) has been developed to provide a more objective and reproducible data about the severity of coronary artery stenosis and the dimensions of the vessel for intervention in real-time, overcoming the limitations of significant inter- and intraobserver variability, and time-consuming nature of on-site QCA, without requiring extra time and effort. Compared with the subjective nature of visually estimated conventional CAG guidance, AI-QCA guidance provides a more practical and standardized angiography-based approach. Although the advantage of intravascular imaging-guided PCI is increasingly recognized, their broader adoption is limited by clinical and economic barriers in many catheterization laboratories. METHODS: The FLASH (fully automated quantitative coronary angiography versus optical coherence tomography guidance for coronary stent implantation) trial is a randomized, investigator-initiated, multicenter, open-label, noninferiority trial comparing the AI-QCA-assisted PCI strategy with optical coherence tomography-guided PCI strategy in patients with significant coronary artery disease. All operators will utilize a novel, standardized AI-QCA software and PCI protocol in the AI-QCA-assisted group. A total of 400 patients will be randomized to either group at a 1:1 ratio. The primary endpoint is the minimal stent area (mm2), determined by the final OCT run after completion of PCI. Clinical follow-up and cost-effectiveness evaluations are planned at 1 month and 6 months for all patients enrolled in the study. RESULTS: Enrollment of a total of 400 patients from the 13 participating centers in South Korea will be completed in February 2024. Follow-up of the last enrolled patients will be completed in August 2024, and primary results will be available by late 2024. CONCLUSION: The FLASH is the first clinical trial to evaluate the feasibility of AI-QCA-assisted PCI, and will provide the clinical evidence on AI-QCA assistance in the field of coronary intervention. CLINICAL TRIAL REGISTRATION: URL: https://www. CLINICALTRIALS: gov. Unique identifier: NCT05388357.

7.
Pediatr Nephrol ; 39(6): 1901-1907, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38240870

RESUMO

BACKGROUND: Shiga toxin-producing E. coli-hemolytic uremic syndrome (STEC-HUS) is associated with high morbidity and relevant mortality. Previous small studies showed that volume expansion could improve the course and outcome of STEC-HUS. The aim of this single-center study was to evaluate the effect of volume expansion on the clinical course and outcome in STEC-HUS. METHODS: Data of pediatric patients with STEC-HUS were analyzed retrospectively. Course and outcome of patients treated with volume expansion (VE) from 2019 to 2022 (n = 38) were compared to historical controls (HC) from 2009 to 2018 (n = 111). RESULTS: Patients in the VE group had a significant relative median weight gain compared to HC (7.8% (3.4-11.3) vs. 1.2% (- 0.7-3.9), p < 0.0001) 48 h after admission. The need for dialysis was not reduced by VE (VE 21/38 (55.3%) vs. HC 64/111 (57.7%), p = 0.8). However, central nervous system involvement (impairment of consciousness, seizures, focal neurological deficits, and/or visual disturbances) was significantly reduced (VE 6/38 (15.8%) vs. HC 38/111 (34.2%), p = 0.039). None of the patients in the VE group died or developed chronic kidney disease (CKD) stage 5, whereas in the HC group, three patients died and three patients had CKD stage 5 at discharge. CONCLUSIONS: This study suggests that volume expansion may be associated with the mitigation of the acute course of STEC-HUS, especially severe neurological involvement and the development of CKD. Prospective trials should lead to standardized protocols for volume expansion in children with STEC-HUS.


Assuntos
Infecções por Escherichia coli , Síndrome Hemolítico-Urêmica , Falência Renal Crônica , Escherichia coli Shiga Toxigênica , Criança , Humanos , Toxina Shiga , Infecções por Escherichia coli/complicações , Estudos Retrospectivos , Estudos Prospectivos , Diálise Renal , Síndrome Hemolítico-Urêmica/complicações , Falência Renal Crônica/complicações
8.
Pediatr Nephrol ; 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38347283

RESUMO

Despite significant medical and technical improvements in the field of dialysis, the morbidity and mortality among patients with chronic kidney disease (CKD) stage 5 on dialysis remains extremely high. Hemodiafiltration (HDF), a dialysis method that combines the two main principles of hemodialysis (HD) and hemofiltration-diffusion and convection-has had a positive impact on survival when delivered with a high convective dose. Improved outcomes with HDF have been attributed to the following factors: HDF removes middle molecular weight uremic toxins including inflammatory cytokines, increases hemodynamic stability, and reduces inflammation and oxidative stress compared to conventional HD. Two randomized trials in adults have shown improved survival with HDF compared to high-flux HD. A large prospective cohort study in children has shown that HDF attenuated the progression of cardiovascular disease, improved bone turnover and growth, reduced inflammation, and improved blood pressure control compared to conventional HD. Importantly, children on HDF reported fewer headaches, dizziness, and cramps; had increased physical activity; and improved school attendance compared to those on HD. In this educational review, we discuss the technical aspects of HDF and results from pediatric studies, comparing outcomes on HDF vs. conventional HD. Convective volume, the cornerstone of treatment with HDF and a key determinant of outcomes in adult randomized trials, is discussed in detail, including the practical aspects of achieving an optimal convective volume.

9.
Pediatr Nephrol ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517536

RESUMO

Cystinosis is a rare autosomal-recessive lysosomal storage disease that progressively affects multiple organs beginning with the kidneys. Patients require lifelong multidisciplinary care for the management of kidney disease and progressive extra-renal manifestations, and thus, they are especially fragile and vulnerable during transition from pediatric to adult care. Previous documents have provided guidance to help the medical transition of these highly burdened patients. Patients and their families often experience great psychological distress and face significant social challenges; for these reasons, they often need help from psychologists, social workers, and other psychosocial professionals. Due to the rarity of the disease, most psychosocial professionals have no expertise in this disorder and require advice. To this end, a steering committee (SC) composed of six experts, including pediatric nephrologists, psychologists, and social workers with experience in the care for patients with cystinosis, have identified and addressed seven key questions related to psychosocial challenges of the disease and the burden of treatment. Ten additional international experts (the extended faculty, EF) were invited to answer these questions. Since robust evidence is lacking, as in many rare diseases, conclusions were based on collective agreement between members of the SC and the EF, and the consolidated answers were summarized into expert opinion statements. The present document contains information on the concerns and psychosocial burden of patients with cystinosis and of their caregivers, and provides practical advice for timely and appropriate support to facilitate the transition to adult care.

10.
Pediatr Nephrol ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850407

RESUMO

BACKGROUND: Infantile nephropathic cystinosis (INC) is a rare lysosomal storage disorder, mostly and often firstly affecting the kidneys, together with impaired disharmonious growth and rickets, eventually resulting in progressive chronic kidney disease (CKD). With the introduction of cysteamine therapy, most pediatric patients reach adulthood with no need for kidney replacement therapy. Still, detailed changes in INC patients' clinical and morphological presentation over the past decades have not yet been thoroughly investigated. METHODS: Two groups with a respective total of 64 children with INC and 302 children with CKD, both treated conservatively and aged 2 to 18 years, were prospectively observed in the time span from 1998 to 2022 with 1186 combined annual clinical and morphological examinations clustered into two measurement periods (1998 to 2015 and ≥ 2016). RESULTS: In INC patients, thoracic proportion indices remained markedly increased, whereas body fat stores remained decreased over the past 25 years (+ 1 vs. below ± 0 z-score, respectively). Their CKD peers presented with overall improved growth, general harmonization of body proportions, and improved body fat stores, while INC patients only presented with an isolated significant increase in leg length over time (∆0.36 z-score). eGFR adjusted for age did not significantly change over the past 25 years in both groups. Alkaline phosphatase (ALP) showed a significant decrease in CKD patients over time, while remaining above normal levels in INC patients. CONCLUSIONS: Disproportionate thoracic shape and impaired body fat stores remain the most characteristic morphological traits in INC patients over the past 25 years, while causal mechanisms remain unclear.

11.
BMC Pediatr ; 24(1): 69, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245705

RESUMO

BACKGROUND: The administration of high-dose intravenous immunoglobulin (IVIG) is a standard treatment for the management of Kawasaki disease (KD). IVIG is known to be a highly effective and safe treatment. CASE PRESENTATION: We report the development of hemolytic anemia in seven children receiving repeated doses of IVIG. The children were aged 3-44 months and included 4 girls and 3 boys. All children received 10% IVIG and a second course of immunoglobulin because they did not respond to the first course of immunoglobulin. Two received high-dose aspirin (50 mg/kg), and five received low-dose aspirin (5 mg/kg). Two patients required additional methylprednisolone pulse therapy (30 mg/kg) after the second dose of immunoglobulin, and three patients received oral prednisolone therapy for defervescence. Three patients showed coronary artery dilation during hospitalization and normalized within two months. Pretreatment hemoglobin averaged 11.3-14.2 g/dL, and post-hemolytic anemia hemoglobin ranged from 7.4 to 9.6 g/dL, with a difference of 1.7-6.8 g/dL. Reticulocytes were increased to 3.3-13.2%. Peripheral blood smears showed normochromic normocytic anemia, and anisopoikilocytosis. All children were positive for warm-type antibodies with IgG+, C3d- in direct antiglobulin test, and the blood group was A + in five and B + in two. None of the patients received immunomodulatory therapy or red blood cell transfusions. They were followed for a year and all recovered. CONCLUSION: Especially, in non-O blood group KD patients who are refractory to initial IVIG and require a second dose of IVIG or 10% formulation the possibility of immune hemolytic anemia should be carefully considered, and close follow-up should be maintained after therapy.


Assuntos
Anemia Hemolítica , Imunoglobulinas Intravenosas , Síndrome de Linfonodos Mucocutâneos , Criança , Feminino , Humanos , Masculino , Anemia Hemolítica/induzido quimicamente , Anemia Hemolítica/terapia , Aspirina/uso terapêutico , Hemoglobinas/uso terapêutico , Imunoglobulinas Intravenosas/efeitos adversos , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Sistema ABO de Grupos Sanguíneos
12.
Klin Padiatr ; 2024 Mar 08.
Artigo em Alemão | MEDLINE | ID: mdl-38458231

RESUMO

Bardet-Biedl syndrome (BBS) is a rare, autosomal recessive multisystem disease. The pathophysiological origin is a dysfunction of the primary cilium. Clinical symptoms are heterogeneous and variable: retinal dystrophy, obesity, polydactyly, kidney abnormalities, hypogenitalism and developmental delays are the most common features. By the approval of the melanocortin 4 receptor agonist setmelanotide, a drug therapy for BBS-associated hyperphagia and obesity can be offered for the first time. Hyperphagia and severe obesity represent a considerable burden and are associated with comorbidity and increased mortality risk. Due to the limited experience with setmelanotide in BBS, a viable comprehensive therapy concept is to be presented. Therapy decision and management should be conducted in expert centers. For best therapeutic effects with setmelanotide adequate information of the patient about the modalities of the therapy (daily subcutaneous injection) and possible adverse drug events are necessary. Furthermore, the involvement of psychologists, nutritionists and nursing services (support for the application) should be considered together with the patient. The assessment of therapy response should be carried out with suitable outcome measurements and centrally reported to an adequate register.

13.
Z Gastroenterol ; 62(7): 1032-1041, 2024 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-38976982

RESUMO

INTRODUCTION: Clostridioides difficile infection (CDI), as a nosocomial disease, is associated with high morbidity and mortality. Even though the incidence of CDI has been declining in Germany in recent years, the individual infection may pose a medical challenge despite therapeutic advances. The aim here is to clarify which gaps practitioners consider to be particularly serious in care and in the existing evidence base. METHODS: In a moderated workshop of German CDI experts the topics considered as relevant were identified. A survey already conducted in five other countries (Australia, France, Great Britain, Canada, and Italy) was adapted and processed by 27 practitioners. During the evaluation, the topics perceived as particularly important were identified, the statements of the specialist groups were compared and changes in opinion were considered. RESULTS: 27 fully completed questionnaires were evaluated. The need for improvement was primarily seen in the prevention of CDI recurrences (74.1%) and the treatment of recurrences (55.6%). Evidence deficits were noted in the treatment of recurrences (55.6%) and identification of risk factors for recurrences (48.1%). Improving care via fecal microbiota transfer (FMT) was named by 70.4%. For guidelines, more clarity (48.1%) and more regular updates (40.7%) were desired. For patients, better education on appropriate antibiotic use (52.0%) and choice of FMT were desired (48.1%). SUMMARY: The German expert view and the international assessment is similar, when asked about the need for improvement in care and evidence gaps in the treatment of patients with CDI: The focus is on prevention and therapy of recurrent CDI. The problem of access to FMT is a German peculiarity that seems to need improvement.


Assuntos
Infecções por Clostridium , Humanos , Infecções por Clostridium/terapia , Infecções por Clostridium/epidemiologia , Alemanha , Melhoria de Qualidade , Internacionalidade , Prova Pericial , Transplante de Microbiota Fecal , Medicina Baseada em Evidências , Avaliação das Necessidades , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/terapia , Guias de Prática Clínica como Assunto
14.
Kidney Int ; 103(3): 464-466, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36822751

RESUMO

The diagnosis of glomerular disease still mostly relies on the conventional histologic and immunohistochemical analysis of biopsies, thereby failing to provide a molecular disease understanding and stratification as the fundamental basis for an individualized therapy. It is out of the question that nephrology will be transformed into a field of systemic molecular precision diagnostics and individualized therapies. However, the time scale and efficiency of such transformation will depend on more studies exemplifying successful translational strategies. The highly heterogeneous glomerular disease entities of minimal change disease and focal segmental glomerular sclerosis seem ideally suited to exploring and ensuring the advancement of an individualized precision nephrology.


Assuntos
Glomerulosclerose Segmentar e Focal , Nefropatias , Nefrologia , Humanos , Patologia Molecular , Nefropatias/patologia , Glomérulos Renais/patologia , Glomerulosclerose Segmentar e Focal/patologia
15.
J Clin Immunol ; 43(1): 46-56, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36121535

RESUMO

Almost 2 years into the pandemic and with vaccination of children significantly lagging behind adults, long-term pediatric humoral immune responses to SARS-CoV-2 are understudied. The C19.CHILD Hamburg (COVID-19 Child Health Investigation of Latent Disease) Study is a prospective cohort study designed to identify and follow up children and their household contacts infected in the early 2020 first wave of SARS-CoV-2. We screened 6113 children < 18 years by nasopharyngeal swab-PCR in a low-incidence setting after general lockdown, from May 11 to June 30, 2020. A total of 4657 participants underwent antibody testing. Positive tests were followed up by repeated PCR and serological testing of all household contacts over 6 months. In total, the study identified 67 seropositive children (1.44%); the median time after infection at first presentation was 83 days post-symptom onset (PSO). Follow-up of household contacts showed less than 100% seroprevalence in most families, with higher seroprevalence in families with adult index cases compared to pediatric index cases (OR 1.79, P = 0.047). Most importantly, children showed sustained seroconversion up to 9 months PSO, and serum antibody concentrations persistently surpassed adult levels (ratio serum IgG spike children vs. adults 90 days PSO 1.75, P < 0.001; 180 days 1.38, P = 0.01; 270 days 1.54, P = 0.001). In a low-incidence setting, SARS-CoV-2 infection and humoral immune response present distinct patterns in children including higher antibody levels, and lower seroprevalence in families with pediatric index cases. Children show long-term SARS-CoV-2 antibody responses. These findings are relevant to novel variants with increased disease burden in children, as well as for the planning of age-appropriate vaccination strategies.


Assuntos
Formação de Anticorpos , COVID-19 , Adulto , Humanos , Criança , SARS-CoV-2 , COVID-19/diagnóstico , COVID-19/epidemiologia , Estudos Prospectivos , Estudos Soroepidemiológicos , Controle de Doenças Transmissíveis , Anticorpos Antivirais
16.
Small ; 19(22): e2300218, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36864579

RESUMO

Metal-organic framework (MOF) nanoparticles have recently emerged as a promising vehicle for drug delivery with high porosity and feasibility. However, employing a MOF-based drug delivery system remains a challenge due to the difficulty in controlling interfaces of particles in a biological environment. In this paper, protein corona-blocked Zr6 -based MOF (PCN-224) nanoparticles are presented for targeted cancer therapy with high efficiency. The unmodified PCN-224 surface is precoated with glutathione transferase (GST)-fused targetable affibody (GST-Afb) proteins via simple mixing conjugations instead of chemical modifications that can induce the impairment of proteins. GST-Afb proteins are shown to stably protect the surface of PCN-224 particles in a specific orientation with GST adsorbed onto the porous surface and the GST-linked Afb posed outward, minimizing the unwanted interfacial interactions of particles with external biological proteins. The Afb-directed cell-specific targeting ability of particles and consequent induction of cell death is demonstrated both in vitro and in vivo by using two kinds of Afb, which targets the surface membrane receptor, human epidermal growth factor receptor 2 (HER2) or epidermal growth factor receptor (EGFR). This study provides insight into the way of regulating the protein-adhesive surface of MOF nanoparticles and designing a more effective MOF-hosted targeted delivery system.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Neoplasias , Humanos , Estruturas Metalorgânicas/metabolismo , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico , Proteínas de Membrana
17.
Opt Express ; 31(11): 18407-18419, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37381552

RESUMO

We report high light extraction from the top emission OLED (TEOLED) device structure by improving mainly the waveguide mode loss in the atomic layer deposition processed thin film encapsulation (TFE) layer. A novel structure incorporating the light extraction concept using evanescent waves and the hermetic encapsulation of a TEOLED device is presented here. When the TEOLED device is fabricated using the TFE layer, a substantial amount of generated light is trapped inside the device due to the difference in refractive index (RI) between the capping layer (CPL) and the aluminum oxide (Al2O3) layer. By inserting a low RI layer at the interface between the CPL and Al2O3, the direction of the internal reflected light is changed by the evanescent waves. The high light extraction with the low RI layer is attributed to the presence of evanescent waves and an electric field in the low RI layer. The novel fabricated TFE structure, CPL/ low RI layer/ Al2O3/ polymer/ Al2O3, is reported here. The current efficiency of the fabricated blue TEOLED device using this low RI layer is improved by about 23% and the blue index value is enhanced by about 26%. This new approach for light extraction will be applicable to future encapsulation technology for flexible optoelectronic devices.

18.
Amino Acids ; 55(10): 1381-1388, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37648945

RESUMO

Guanidino compounds such as dimethylarginines (SDMA, ADMA) and L-homoarginine ((L-)hArg) can interfere with bioavailability and function of the main NO-donor L-arginine (L-Arg). High ADMA and SDMA but low L-hArg concentrations have been associated with cardio- and cerebrovascular events and mortality in adults. The role of guanidino compounds in paediatric patients remains less clear. We, therefore, compared guanidino compound levels in plasma samples of 57 individuals with chronic kidney disease (CKD) and 141 individuals without CKD from the age of 0 to 17 years, including patients with different comorbidities by correlation and regression analyses. We found highest hArg, SDMA and ADMA concentrations in neonates (Kruskal-Wallis, p < 0.001 for all). From the age of 1 year on, hArg levels increased, whereas SDMA und ADMA levels further decreased in children. SDMA and ADMA are higher in children with CKD independent of GFR (mean factor 1.92 and 1.38, respectively, p < 0.001 for both), and SDMA is strongly correlated with creatinine concentration in children with CKD (Spearman's rho 0.74, p < 0.001). We provide guanidino compound levels in a large sample covering all paediatric age groups for the first time. Our data can be used to assess the role of guanidino compounds such as hArg in disease states, i.e. cerebro- and cardiovascular disorders in childhood and adolescence.


Assuntos
Doenças Cardiovasculares , Insuficiência Renal Crônica , Adulto , Recém-Nascido , Humanos , Adolescente , Criança , Lactente , Pré-Escolar , Homoarginina , Arginina , Coração
19.
Langmuir ; 39(15): 5426-5439, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37014907

RESUMO

Bacterial fouling is a persistent problem causing the deterioration and failure of functional surfaces for industrial equipment/components; numerous human, animal, and plant infections/diseases; and energy waste due to the inefficiencies at internal and external geometries of transport systems. This work gains new insights into the effect of surface roughness on bacterial fouling by systematically studying bacterial adhesion on model hydrophobic (methyl-terminated) surfaces with roughness scales spanning from ∼2 nm to ∼390 nm. Additionally, a surface energy integration framework is developed to elucidate the role of surface roughness on the energetics of bacteria and substrate interactions. For a given bacteria type and surface chemistry; the extent of bacterial fouling was found to demonstrate up to a 75-fold variation with surface roughness. For the cases showing hydrophobic wetting behavior, both increased effective surface area with increasing roughness and decreased activation energy with increased surface roughness was concluded to enhance the extent of bacterial adhesion. For the cases of superhydrophobic surfaces, the combination of factors including (i) the surpassing of Laplace pressure force of interstitial air over bacterial adhesive force, (ii) the reduced effective substrate area for bacteria wall due to air gaps to have direct/solid contact, and (iii) the reduction of attractive van der Waals force that holds adhering bacteria on the substrate were summarized to weaken the bacterial adhesion. Overall, this study is significant in the context of designing antifouling coatings and systems as well as explaining variations in bacterial contamination and biofilm formation processes on functional surfaces.


Assuntos
Aderência Bacteriana , Nanoestruturas , Animais , Humanos , Aderência Bacteriana/fisiologia , Propriedades de Superfície , Molhabilidade , Interações Hidrofóbicas e Hidrofílicas
20.
Nephrol Dial Transplant ; 38(10): 2170-2181, 2023 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-36754369

RESUMO

BACKGROUND: The unphysiological composition of peritoneal dialysis (PD) fluids induces progressive peritoneal fibrosis, hypervascularization and vasculopathy. Information on these alterations after kidney transplantation (KTx) is scant. METHODS: Parietal peritoneal tissues were obtained from 81 pediatric patients with chronic kidney disease stage 5 (CKD5), 72 children on PD with low glucose degradation product (GDP) PD fluids, and from 20 children 4-8 weeks after KTx and preceding low-GDP PD. Tissues were analyzed by digital histomorphometry and quantitative immunohistochemistry. RESULTS: While chronic PD was associated with peritoneal hypervascularization, after KTx vascularization was comparable to CKD5 level. Submesothelial CD45 counts were 40% lower compared with PD, and in multivariable analyses independently associated with microvessel density. In contrast, peritoneal mesothelial denudation, submesothelial thickness and fibrin abundance, number of activated, submesothelial fibroblasts and of mesothelial-mesenchymal transitioned cells were similar after KTx. Diffuse peritoneal podoplanin positivity was present in 40% of the transplanted patients. In subgroups matched for age, PD vintage, dialytic glucose exposure and peritonitis incidence, submesothelial hypoxia-inducible factor 1-alpha abundance and angiopoietin 1/2 ratio were lower after KTx, reflecting vessel maturation, while arteriolar and microvessel p16 and cleaved Casp3 were higher. Submesothelial mast cell count and interleukin-6 were lower, whereas transforming growth factor-beta induced pSMAD2/3 was similar as compared with children on PD. CONCLUSIONS: Peritoneal membrane damage induced with chronic administration of low-GDP PD fluids was less severe after KTx. While peritoneal microvessel density, primarily defining PD transport and ultrafiltration capacity, was normal after KTx and peritoneal inflammation less pronounced, diffuse podoplanin positivity and profibrotic activity were prevalent.


Assuntos
Falência Renal Crônica , Transplante de Rim , Diálise Peritoneal , Peritonite , Humanos , Criança , Transplante de Rim/efeitos adversos , Diálise Renal , Diálise Peritoneal/efeitos adversos , Peritônio/metabolismo , Soluções para Diálise/metabolismo , Peritonite/metabolismo , Falência Renal Crônica/cirurgia , Falência Renal Crônica/metabolismo , Glucose/metabolismo
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