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1.
Autoimmunity ; 57(1): 2356089, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38770919

RESUMO

Autoimmune hepatitis (AIH) is a chronic, inflammatory liver disease of unknown aetiology which requires lifelong immunosuppression. Most therapeutic and outcome studies of AIH have been conducted predominantly in Caucasian (European Ancestry, EA) cohorts, with the exclusion of African American (AA) patients due to inadequate sample size. It is known that AA patients have a severe phenotype of autoimmune diseases and demonstrate a poor response to conventional medical therapy. Understanding cellular and molecular pathways which determine AIH severity and progression in AA patients is likely to lead to the discovery of novel, personalised and better tolerated therapies. The aim of the study is to determine the distinct effector B cell phenotypes which contribute to disease severity and progression of AIH in AA children as compared to their EA cohorts. PBMCs were isolated from blood samples collected from patients visiting Children's Healthcare of Atlanta (CHOA) and were grouped into AA, (n = 12), EA, (n = 11) and controls (n = 12) and were processed for flow cytometry. Markers of B cell development, maturation and activation were assessed namely CD19, CD21, IgD, CD27, CD38, CD11c, CD24, CD138. AA children with AIH demonstrated an expansion of CD19 + ve, Activated Naïve (aN), (CD19+ IgD-/CD27- Double Negative (DN2) ([CD19+/IgD-/CD27++CD38++) cells. Plasmablasts were significantly higher along with Signalling Lymphocytic activation molecule F7 (SLAMF7). Unswitched memory [CD19+] IgD+CD27+ (USM) B cells were significantly contracted in AA patients with AIH. B cell phenotyping reveals a distinct profile in AA AIH patients with a major skewing towards the expansion of effector pathways which have been previously characterised in severe SLE in AA patients. These results suggest that the quantification and therapeutic target of B cell pathway could contribute substantially to the clinical approach to AIH especially in the AA population.


Assuntos
Linfócitos B , Hepatite Autoimune , Imunoglobulina D , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral , Humanos , Hepatite Autoimune/imunologia , Hepatite Autoimune/sangue , Hepatite Autoimune/patologia , Hepatite Autoimune/diagnóstico , Imunoglobulina D/imunologia , Imunoglobulina D/metabolismo , Criança , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo , Masculino , Feminino , Adolescente , Linfócitos B/imunologia , Linfócitos B/metabolismo , Pré-Escolar , Imunofenotipagem , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/metabolismo , Idade de Início , Biomarcadores
2.
J Stomatol Oral Maxillofac Surg ; : 101876, 2024 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-38636805

RESUMO

This article has been withdrawn at the request of the authors. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/policies/article-withdrawal

3.
Aliment Pharmacol Ther ; 59(10): 1236-1247, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38462727

RESUMO

BACKGROUND: Data on oral vancomycin for primary sclerosing cholangitis (PSC)-associated inflammatory bowel disease (IBD) are limited. AIMS: Using data from the Paediatric PSC Consortium, to examine the effect of vancomycin on IBD activity. METHODS: In this retrospective multi-centre cohort study, we matched vancomycin-treated and untreated patients (1:3) based on IBD duration at the time of primary outcome assessment. The primary outcome was Physician Global Assessment (PGA) of IBD clinical activity after 1 year (±6 months) of vancomycin. We used generalised estimating equations (GEE) to examine the association between vancomycin and PGA remission, adjusting for IBD type, severity and medication exposures. Secondary outcomes included serum labs and endoscopic remission (global rating of no activity) among those with available data and also analysed with GEE. RESULTS: 113 PSC-IBD patients received vancomycin (median age 12.7 years, 63% male). The matched cohort included 70 vancomycin-treated and 210 untreated patients. Vancomycin was associated with greater odds of IBD clinical remission (odds ratio [OR] 3.52, 95% CI 1.97-6.31; adjusted OR [aOR] 5.24, 95% CI 2.68-10.22). Benefit was maintained in sensitivity analyses restricted to non-transplanted patients and those with baseline moderate-severe PGA. Vancomycin was associated with increased odds of endoscopic remission (aOR 2.76, 95% CI 1.002-7.62; N = 101 with data), and with lower CRP (p = 0.03) and higher haemoglobin and albumin (both p < 0.01). CONCLUSION: Vancomycin was associated with greater odds of IBD clinical and endoscopic remission. Additional, preferably randomised, controlled studies are needed to characterise efficacy using objective markers of mucosal inflammation, and to examine safety and define optimal dosing.


Assuntos
Antibacterianos , Colangite Esclerosante , Doenças Inflamatórias Intestinais , Vancomicina , Humanos , Vancomicina/administração & dosagem , Vancomicina/efeitos adversos , Colangite Esclerosante/tratamento farmacológico , Colangite Esclerosante/complicações , Feminino , Masculino , Estudos Retrospectivos , Criança , Adolescente , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Antibacterianos/efeitos adversos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/complicações , Administração Oral , Resultado do Tratamento , Índice de Gravidade de Doença , Indução de Remissão , Estudos de Coortes
4.
Curr Microbiol ; 81(4): 103, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38386082

RESUMO

Citrus is an economically important fruit crop, belongs to family Rutaceae, cultivated commercially in over 130 countries, which holds a leading profitable position in the international market. The most important citrus varieties are mandarins, oranges, lemons, sweet limes, grapefruits and pomelos. Citrus yellow vein clearing virus (CYVCV) is an important graft transmissible plant pathogen known to reduce productivity of citrus fruits due to its predominant association and widespread occurrence. Requirement of fast, reliable, efficient & economical CYVCV indexing assay is a prerequisite for production of healthy planting material. Currently, nucleic acid isolation and thermal cycler-based assay available for CYVCV indexing is a cumbersome lab intensive method. The present study was undertaken to develop and validate reverse transcription-recombinase polymerase amplification (RT-RPA) assay requiring no tedious RNA isolation, separate cDNA synthesis and costlier instrument like thermo-cycler. Optimized RT-RPA assay was able to amplify CYVCV up to 10-7 dilution (equivalent to 0.1 pg/µl) with the prepared templates of both RNA and crude saps and showed higher sensitivity in detection of CYVCV infection in field samples as compared to the conventional RT-PCR. Developed RT-RPA assay showed high specificity without any cross-reaction with other citrus pathogens (Indian citrus ringspot virus, citrus yellow mosaic virus, citrus tristeza virus, citrus exocortis viroid and huanglongbing). RT-RPA using crude leaf sap as template is quite simple, robust, highly sensitive, time and cost effective; therefore, it can be used in resource constrained laboratories as screening tool, for field surveys and on-site testing programs in farms, nurseries and biosecurity. Present study, first time reports the development, optimization and validation of crude sap-based RT-RPA assay for the detection of CYVCV infection in citrus plants namely; Kinnow mandarin, Mosambi and Grape fruit.


Assuntos
Citrus , Recombinases , Recombinases/genética , Bioensaio , Fazendas , RNA
5.
Mol Biotechnol ; 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38366109

RESUMO

Calanthe mild mosaic virus (CalMMV) infecting orchids is an important potyvirus which is known to cause mild leaf mosaic and flower colour-breaking symptoms in Calanthe and other orchid plants. The present study reports the production of polyclonal antibodies against CalMMV using bacterially expressed recombinant coat protein as immunogen, which in turn would be useful in routine indexing and screening of orchid germplasm. The coat protein (CP) gene (~ 807 bp) of CalMMV isolated from infected orchid sample was cloned in expression vector, pET-28a ( +) that yielded ~ 31 kDa fusion protein with Histidine tag (His6BP). The expression of fusion CP was confirmed through SDS-PAGE and Western blotting. The His6BP-CalMMV-CP obtained in soluble state after purification was used to immunize New Zealand white rabbit for the production of polyclonal antibodies (PAb). The PAb produced against the purified fusion protein successfully detected CAlMMV in the orchid samples at a dilution of 1:2000 in direct antigen-coated enzyme-linked immunosorbent assay (DAC-ELISA). This study presents the first report of Histidine tag (His6BP) fusion CalMMV-CP-based antibody production and its successful application in the identification of the virus in orchid plants. Outcome of this study will be helpful in routine certification programmes, screening of orchid germplasm and production of CalMMV-free planting materials of orchids.

6.
Transplantation ; 108(4): 940-946, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37831642

RESUMO

BACKGROUND: The social determinants of health contribute to adverse post-liver transplant outcomes. Identifying unmet social risks may enable transplant teams to improve long-term outcomes for at-risk children. However, providers may feel uncomfortable asking about household-level social risks in the posttransplant period because they might make their patients/families uncomfortable. METHODS: We conducted a mixed-methods analysis of caregiver participants (ie, parents/guardians of pediatric liver transplant recipients) in the Social and Contextual Impact on Children Undergoing Liver Transplantation study to assess their perceptions of provider-based social risk screening. Participants (N = 109) completed a 20-min social determinants of health questionnaire that included questions on the acceptability of being asked intimate social risk questions. A subset of participants (N = 37) engaged in an in-depth qualitative interview to share their perceptions of social risk screening. RESULTS: Of 109 participants across 9 US transplant centers, 60% reported financial strain and 30% reported at least 1 material economic hardship (eg, food insecurity, housing instability). Overall, 65% of respondents reported it very or somewhat appropriate and 25% reported being neutral to being screened for social risks in a liver transplant setting. In qualitative analyses, participants reported trust in the providers and a clear understanding of the intention of the screening as prerequisites for liver transplant teams to perform social risk screening. CONCLUSIONS: Only a small minority of caregivers found social risk screening unacceptable. Pediatric liver transplant programs should implement routine social risk screening and prioritize the patient and family voices when establishing a screening program to ensure successful implementation.


Assuntos
Cuidadores , Transplante de Fígado , Humanos , Criança , Transplante de Fígado/efeitos adversos , Habitação , Pobreza , Determinantes Sociais da Saúde
7.
Indian J Otolaryngol Head Neck Surg ; 75(4): 3679-3685, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37974701

RESUMO

Comparative evaluation of early and late tracheostomy outcomes in mechanically ventilated patients. The present retrospective study was conducted in Government medical college Jammu from April 2021 to November 2022 on 111 tracheotomised patient in intensive care unit. All tracheostomies with in 10 days of intubation were grouped as early tracheostomy (ET) group and all those done after 10 days were grouped as LATE TRACHEOSTOMY (LT) group. APACHE II score at the time of intensive care unit admission of all included tracheotomised patients was noted. Data regarding mortality, duration of mechanical ventilation and length of stay in intensive care unit (ICU) was studied. Mean age of presentation was 41.5 ± 15.7 yrs, with male preponderance. Out of 111 patients, 57 patients underwent early tracheostomy and 54 underwent late TRACHEOSTOMY. In APACHE II, < 25 category-short term mortality was 4 in ET and 5 in LT; long term mortality in ET was 4 and 10 in LT; average days of mechanical ventilation were 11.2 in ET and 3 in LT; average stay in ICU was 18 days in ET and 61 days in LT. in APACHE II > 25-short term mortality was 4 in ET and 5 in LT; long term mortality in ET was 3 and 9 in LT. Average days of mechanical ventilation were 10.8 in ET and 57 in LT; average stay in ICU was 24 days in ET and 79 days in LT. Early tracheostomy is superior to late Tracheostomy in terms of mortality, number of days of mechanical ventilation and the duration of intensive care unit stay.

8.
JAMA Netw Open ; 6(10): e2337602, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37824141

RESUMO

Importance: Live vaccines (measles-mumps-rubella [MMR] and varicella-zoster virus [VZV]) have not been recommended after solid organ transplant due to concern for inciting vaccine strain infection in an immunocompromised host. However, the rates of measles, mumps, and varicella are rising nationally and internationally, leaving susceptible immunocompromised children at risk for life-threating conditions. Objective: To determine the safety and immunogenicity of live vaccines in pediatric liver and kidney transplant recipients. Design, Setting, and Participants: This cohort study included select pediatric liver and kidney transplant recipients who had not completed their primary MMR and VZV vaccine series and/or who displayed nonprotective serum antibody levels at enrollment between January 1, 2002, and February 28, 2023. Eligibility for live vaccine was determined by individual US pediatric solid organ transplant center protocols. Exposures: Exposure was defined as receipt of a posttransplant live vaccine. Transplant recipients received 1 to 3 doses of MMR vaccine and/or 1 to 3 doses of VZV vaccine. Main Outcome and Measure: Safety data were collected following each vaccination, and antibody levels were obtained at 0 to 3 months and 1 year following vaccination. Comparisons were performed using Mann-Whitney U test, and factors associated with development of postvaccination protective antibodies were explored using univariate analysis. Results: The cohort included 281 children (270 [96%] liver, 9 [3%] kidney, 2 [1%] liver-kidney recipients) from 18 centers. The median time from transplant to enrollment was 6.3 years (IQR, 3.4-11.1 years). The median age at first posttransplant vaccine was 8.9 years (IQR, 4.7-13.8 years). A total of 202 of 275 (73%) children were receiving low-level monotherapy immunosuppression at the time of vaccination. The majority of children developed protective antibodies following vaccination (107 of 149 [72%] varicella, 130 of 152 [86%] measles, 100 of 120 [83%] mumps, and 124 of 125 [99%] rubella). One year post vaccination, the majority of children who initially mounted protective antibodies maintained this protection (34 of 44 [77%] varicella, 45 of 49 [92%] measles, 35 of 42 [83%] mumps, 51 of 54 [94%] rubella). Five children developed clinical varicella, all of which resolved within 1 week. There were no cases of measles or rubella and no episodes of graft rejection within 1 month of vaccination. There was no association between antibody response and immunosuppression level at the time of vaccination. Conclusions and Relevance: The findings suggest that live vaccinations may be safe and immunogenic after solid organ transplant in select pediatric recipients and can offer protection against circulating measles, mumps, and varicella.


Assuntos
Varicela , Sarampo , Caxumba , Rubéola (Sarampo Alemão) , Vacinas Virais , Criança , Humanos , Pré-Escolar , Adolescente , Varicela/prevenção & controle , Vacina contra Varicela/efeitos adversos , Vacinas Combinadas , Transplantados , Estudos de Coortes , Rubéola (Sarampo Alemão)/prevenção & controle , Sarampo/prevenção & controle , Vacinas Atenuadas/efeitos adversos
9.
J Physiol ; 601(17): 3739-3764, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37428651

RESUMO

Calmodulin (CaM) is a highly conserved mediator of calcium (Ca2+ )-dependent signalling and modulates various cardiac ion channels. Genotyping has revealed several CaM mutations associated with long QT syndrome (LQTS). LQTS patients display prolonged ventricular recovery times (QT interval), increasing their risk of incurring life-threatening arrhythmic events. Loss-of-function mutations to Kv7.1 (which drives the slow delayed rectifier potassium current, IKs, a key ventricular repolarising current) are the largest contributor to congenital LQTS (>50% of cases). CaM modulates Kv7.1 to produce a Ca2+ -sensitive IKs, but little is known about the consequences of LQTS-associated CaM mutations on Kv7.1 function. Here, we present novel data characterising the biophysical and modulatory properties of three LQTS-associated CaM variants (D95V, N97I and D131H). We showed that mutations induced structural alterations in CaM and reduced affinity for Kv7.1, when compared with wild-type (WT). Using HEK293T cells expressing Kv7.1 channel subunits (KCNQ1/KCNE1) and patch-clamp electrophysiology, we demonstrated that LQTS-associated CaM variants reduced current density at systolic Ca2+ concentrations (1 µm), revealing a direct QT-prolonging modulatory effect. Our data highlight for the first time that LQTS-associated perturbations to CaM's structure impede complex formation with Kv7.1 and subsequently result in reduced IKs. This provides a novel mechanistic insight into how the perturbed structure-function relationship of CaM variants contributes to the LQTS phenotype. KEY POINTS: Calmodulin (CaM) is a ubiquitous, highly conserved calcium (Ca2+ ) sensor playing a key role in cardiac muscle contraction. Genotyping has revealed several CaM mutations associated with long QT syndrome (LQTS), a life-threatening cardiac arrhythmia syndrome. LQTS-associated CaM variants (D95V, N97I and D131H) induced structural alterations, altered binding to Kv7.1 and reduced IKs. Our data provide a novel mechanistic insight into how the perturbed structure-function relationship of CaM variants contributes to the LQTS phenotype.


Assuntos
Calmodulina , Síndrome do QT Longo , Humanos , Calmodulina/genética , Calmodulina/metabolismo , Cálcio/metabolismo , Células HEK293 , Síndrome do QT Longo/genética , Mutação , Canal de Potássio KCNQ1/genética
10.
Front Plant Sci ; 14: 1151471, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36968414

RESUMO

Geminiviruses are known to infect several fields and horticultural crops around the globe. Grapevine geminivirus A (GGVA) was reported in the United States in 2017, and since then, it has been reported in several countries. The complete genome recovered through high-throughput sequencing (HTS)-based virome analysis in Indian grapevine cultivars had all of the six open reading frames (ORFs) and a conserved nonanucleotide sequence 5'-TAATATTAC-3' similar to all other geminiviruses. Recombinase polymerase amplification (RPA), an isothermal amplification technique, was developed for the detection of GGVA in grapevine samples employing crude sap lysed in 0.5 M NaOH solution and compared with purified DNA/cDNA as a template. One of the key advantages of this assay is that it does not require any purification or isolation of the viral DNA and can be performed in a wide range of temperatures (18°C-46°C) and periods (10-40 min), which makes it a rapid and cost-effective method for the detection of GGVA in grapevine. The developed assay has a sensitivity up to 0.1 fg µl-1 using crude plant sap as a template and detected GGVA in several grapevine cultivars of a major grapevine-growing area. Because of its simplicity and rapidity, it can be replicated for other DNA viruses infecting grapevine and will be a very useful technique for certification and surveillance in different grapevine-growing regions of the country.

11.
Lett Appl Microbiol ; 76(2)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36794889

RESUMO

Leek yellow stripe virus (LYSV) is one of the most important potyviruses, associated with garlic throughout the world, including India. LYSV causes stunting and yellow streaks in garlic and leek leaves and with other coinfecting viruses leading to severe symptom expression and yield reduction. In this study, we have made the first reported attempt to produce specific polyclonal antibodies to LYSV using expressed recombinant coat protein (CP), which would be useful for screening and routine indexing of the garlic germplasm. The CP gene was cloned, sequenced, and further subcloned in pET-28a(+) expression vector, which yielded ∼35 kDa fusion protein. The fusion protein was obtained in insoluble fraction after purification and its identity was confirmed by SDS-PAGE and western blotting. The purified protein was used as immunogen for production of polyclonal antisera in New Zealand white rabbit. Antisera raised, was able to recognize the corresponding recombinant proteins in western blotting, immunosorbent electron microscopy and dot immunobinding assay (DIBA). Developed antisera to LYSV (titer 1:2000) was used for screening of 21 garlic accessions in antigen coated plate enzyme-linked immunosorbent assay (ACP-ELISA) and 16 accessions were found positive for LYSV, indicating its widespread presence within the collection tested. To the best of our knowledge, this is the first report of a polyclonal antiserum against the in-vitro expressed CP of LYSV and its successful application in diagnosis of LYSV in garlic accessions in India.


Assuntos
Alho , Potyvirus , Animais , Coelhos , Cebolas , Escherichia coli/genética , Sequência de Bases , Proteínas Recombinantes/genética , Alho/genética , Potyvirus/genética , Soros Imunes/genética
12.
Pediatr Transplant ; 27(1): e14409, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36272132

RESUMO

BACKGROUND: Patient-reported outcome measures (PROMs) are not routinely used in clinical care by pediatric liver transplant (LT) teams. The Starzl Network for Excellence in Pediatric Transplantation (SNEPT) assessed feasibility of using a disease-specific Quality of Life (QoL) questionnaire in the ambulatory setting at 10 SNEPT sites. METHODS: A mixed methods feasibility project assessing administration processes, barriers, and user experiences with the Pediatric Liver Transplant Quality of Life (PeLTQL) tool. Iterative processes sought stakeholder feedback across four phases (Pilot, Extended Pilot, Development of a Mobile App PeLTQL version, and Pilot App use). RESULTS: A total of 149 patient-parent dyads completed the PeLTQL during LT clinic follow-up. Clinicians, parents, and patients evaluated and reported on feasibility of operationalization. Only two of 10 SNEPT sites continued PeLTQL administration after the initial two pilot phases. Reasons include limited clinical time and available personnel aggravated by the COVID-19 pandemic. In response, a mobile application version of the PeLTQL was initiated. Providing PeLTQL responses electronically was "very easy" or "easy" as reported by 96% (22/23) parents. CONCLUSIONS: Administration of a PROM into post-pediatric LT clinical care was feasible, but ongoing utilization stalled. Use of a mobile app towards facilitating completion of the PeLTQL outside of clinic hours may address the time and work-flow barriers identified.


Assuntos
COVID-19 , Transplante de Fígado , Criança , Humanos , Qualidade de Vida , Estudos de Viabilidade , Pandemias , Medidas de Resultados Relatados pelo Paciente
13.
J Biol Chem ; 299(1): 102777, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36496072

RESUMO

Long QT syndrome (LQTS) is a human inherited heart condition that can cause life-threatening arrhythmia including sudden cardiac death. Mutations in the ubiquitous Ca2+-sensing protein calmodulin (CaM) are associated with LQTS, but the molecular mechanism by which these mutations lead to irregular heartbeats is not fully understood. Here, we use a multidisciplinary approach including protein biophysics, structural biology, confocal imaging, and patch-clamp electrophysiology to determine the effect of the disease-associated CaM mutation E140G on CaM structure and function. We present novel data showing that mutant-regulated CaMKIIδ kinase activity is impaired with a significant reduction in enzyme autophosphorylation rate. We report the first high-resolution crystal structure of a LQTS-associated CaM variant in complex with the CaMKIIδ peptide, which shows significant structural differences, compared to the WT complex. Furthermore, we demonstrate that the E140G mutation significantly disrupted Cav1.2 Ca2+/CaM-dependent inactivation, while cardiac ryanodine receptor (RyR2) activity remained unaffected. In addition, we show that the LQTS-associated mutation alters CaM's Ca2+-binding characteristics, secondary structure content, and interaction with key partners involved in excitation-contraction coupling (CaMKIIδ, Cav1.2, RyR2). In conclusion, LQTS-associated CaM mutation E140G severely impacts the structure-function relationship of CaM and its regulation of CaMKIIδ and Cav1.2. This provides a crucial insight into the molecular factors contributing to CaM-mediated arrhythmias with a central role for CaMKIIδ.


Assuntos
Canais de Cálcio Tipo L , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Calmodulina , Síndrome do QT Longo , Humanos , Arritmias Cardíacas/genética , Arritmias Cardíacas/fisiopatologia , Cálcio/metabolismo , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Calmodulina/genética , Calmodulina/metabolismo , Síndrome do QT Longo/genética , Miócitos Cardíacos/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Mutação , Estrutura Secundária de Proteína/genética , Ligação Proteica/genética , Cristalografia
14.
Sci Rep ; 12(1): 18663, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36333377

RESUMO

Pediatric liver transplantation rejection affects 20% of children. Currently, liver biopsy, expensive and invasive, is the best method of diagnosis. Discovery and validation of clinical biomarkers from blood or other biospecimens would improve clinical care. For this study, stored plasma samples were utilized from two cross-sectional cohorts of liver transplant patients at Children's Healthcare of Atlanta. High resolution metabolic profiling was completed using established methods. Children with (n = 18) or without (n = 25) acute cellular rejection were included in the analysis (n = 43 total). The mean age of these racially diverse cohorts ranged from 12.6 years in the rejection group and 13.6 years in the no rejection group. Linear regression provided 510 significantly differentiating metabolites between groups, and OPLS-DA showed 145 metabolites with VIP > 2. A total of 95 overlapping significant metabolites between OPLS-DA and linear regression analyses were detected. Pathway analysis (p < 0.05) showed bile acid biosynthesis and tryptophan metabolism as the top two differentiating pathways. Network analysis also identified tryptophan and clustered with liver enzymes and steroid use. We conclude metabolic profiling of plasma from children with acute liver transplant rejection demonstrates > 500 significant metabolites. This result suggests that development of a non-invasive biomarker-based test is possible for rejection screening.


Assuntos
Rejeição de Enxerto , Transplante de Fígado , Humanos , Criança , Rejeição de Enxerto/patologia , Estudos Transversais , Triptofano , Metabolômica/métodos , Fígado/patologia , Biomarcadores , Complicações Pós-Operatórias/patologia
15.
Appl Immunohistochem Mol Morphol ; 30(10): 647-653, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36222506

RESUMO

The membrane protein angiotensin-converting enzyme-2 (ACE2) has gained notoriety as the receptor for severe acute respiratory syndrome coronavirus 2. Prior evidence has shown ACE2 is expressed within the liver but its function has not been fully discerned. Here, we utilized novel methodology to assess ACE2 expression in pediatric immune-mediated liver disease to better understand its presence in liver diseases and its role during infections such as COVID-19. We stained liver tissue with ACE2-specific immunofluorescent antibodies, analyzed via confocal microscopy. Computational deep learning-based segmentation models identified nuclei and cells, allowing the quantification of mean cellular and cytosolic immunofluorescent. Spatial transcriptomics provided high-throughput gene expression analysis in tissue to determine cellular composition for ACE2 expression. ACE2 plasma expression was quantified via enzyme-linked immunosorbent assay. High ACE2 expression was seen at the apical surface of cholangiocytes, with lower expression within hepatocyte cytosol and nonparenchymal cells ( P <0.001). Children with liver disease had higher ACE2 hepatic expression than pediatric control tissue ( P <0.001). Adult control tissue had higher expression than pediatric control ( P <0.001). Plasma ACE2 was not found to be statistically different between samples. Spatial transcriptomics identified cell composition of ACE2-expressing spots containing antibody-secreting cells. Our results show ACE2 expression throughout the liver, with strongest localization to cholangiocyte membranes. Machine learning can be used to rapidly identify hepatic cellular components for histologic analysis. ACE2 expression in the liver may be increased in pediatric liver disease. Future work is needed to better understand the role of ACE2 in chronic disease and acute infections.


Assuntos
COVID-19 , Hepatopatias , Humanos , Criança , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Angiotensinas
16.
Am J Physiol Gastrointest Liver Physiol ; 323(4): G306-G317, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35916405

RESUMO

The alternative (noncanonical) nuclear factor-κB (NF-κB) signaling pathway predominantly regulates the function of the p52/RelB heterodimer. Germline Nfkb2 deficiency in mice leads to loss of p100/p52 protein and offers protection against a variety of gastrointestinal conditions, including azoxymethane/dextran sulfate sodium (DSS)-induced colitis-associated cancer and lipopolysaccharide (LPS)-induced small intestinal epithelial apoptosis. However, the common underlying protective mechanisms have not yet been fully elucidated. We applied high-throughput RNA-Seq and proteomic analyses to characterize the transcriptional and protein signatures of the small intestinal mucosa of naïve adult Nfkb2-/- mice. Those data were validated by immunohistochemistry and quantitative ELISA using both small intestinal tissue lysates and serum. We identified a B-lymphocyte defect as a major transcriptional signature in the small intestinal mucosa and immunoglobulin A as the most downregulated protein by proteomic analysis in Nfkb2-/- mice. Small intestinal immunoglobulins were dramatically dysregulated, with undetectable levels of immunoglobulin A and greatly increased amounts of immunoglobulin M being detected. The numbers of IgA-producing, cluster of differentiation (CD)138-positive plasma cells were also reduced in the lamina propria of the small intestinal villi of Nfkb2-/- mice. This phenotype was even more striking in the small intestinal mucosa of RelB-/- mice, although these mice were equally sensitive to LPS-induced intestinal apoptosis as their RelB+/+ wild-type counterparts. NF-κB2/p52 deficiency confers resistance to LPS-induced small intestinal apoptosis and also appears to regulate the plasma cell population and immunoglobulin levels within the gut.NEW & NOTEWORTHY Novel transcriptomic analysis of murine proximal intestinal mucosa revealed an unexpected B cell signature in Nfkb2-/- mice. In-depth analysis revealed a defect in the CD38+ B cell population and a gut-specific dysregulation of immunoglobulin levels.


Assuntos
Subunidade p52 de NF-kappa B , Plasmócitos , Animais , Imunoglobulina A/metabolismo , Imunoglobulinas/metabolismo , Mucosa Intestinal/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , NF-kappa B/metabolismo , Subunidade p52 de NF-kappa B/genética , Subunidade p52 de NF-kappa B/metabolismo , Plasmócitos/metabolismo , Proteômica
17.
Clin Liver Dis ; 26(3): 489-519, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35868687

RESUMO

This article reviews recent literature on the pathogenesis, presentation, diagnosis, comorbidities, natural history, and management of pediatric primary sclerosing cholangitis (PSC). The authors shed light on the role of genetic and environmental factors in PSC, although recognize the limitations in the understanding of PSC pathogenesis. They reflect on presenting disease phenotypes, including the association with inflammatory bowel disease and frequent histologic presence of autoimmune hepatitis features. The current lack of effective medications is discussed, and disease complications and prognosis are described. Finally, the authors highlight available evidence while acknowledging the paucity of prospective pediatric data.


Assuntos
Colangite Esclerosante , Hepatite Autoimune , Doenças Inflamatórias Intestinais , Colangite Esclerosante/diagnóstico , Colangite Esclerosante/epidemiologia , Colangite Esclerosante/etiologia , Hepatite Autoimune/diagnóstico , Hepatite Autoimune/epidemiologia , Hepatite Autoimune/terapia , Humanos , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/epidemiologia , Doenças Inflamatórias Intestinais/etiologia , Prognóstico , Estudos Prospectivos
19.
J Pediatr Gastroenterol Nutr ; 75(5): 623-628, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35767565

RESUMO

OBJECTIVES: To analyze demographic, psychosocial, and clinical factors in pediatric liver transplant recipients for their association with death or loss to follow up in adulthood. We aimed to better understand known health disparities in transplant outcomes and identify potentially modifiable risk factors prior to transfer. METHODS: A retrospective cohort study of children who underwent liver transplantation at a large tertiary transplant center and were transferred to adult care between 2000 and 2015. RESULTS: During the study period, 101 qualifying patients were transferred. Ninety-three individuals followed with an adult provider, while 8 were lost to follow up. In total 23 of 93 patients died after transfer (24.7%). Several childhood factors were associated with adult death: Black race [odds ratio (OR) 6.59, P < 0.001]; psychiatric illness or substance use (OR 2.81, P = 0.04); failure to graduate high school before transfer (OR 9.59, P < 0.001); posttransplant tacrolimus medication-level variability index >2.5 (OR 5.36, P = 0.04); provider documentation of medication nonadherence (OR 4.72, P = 0.02); acute cellular rejection (OR 4.44, P = 0.03); the presence of diabetes mellitus (OR 5.71, P = 0.001), and chronic kidney disease (OR 2.82, P = 0.04). Failure to graduate HS was associated with loss to follow up ( P < 0.001). On multivariate analysis, Black race, substance use, diabetes, and failure to graduate HS retained association with adult death (each P < 0.05). CONCLUSIONS: Complex, intertwined patient characteristics are associated with increased odds of death in pediatric liver transplant recipients transferred to adult care. Early recognition of high-risk patients and intervention for modifiable factors, such as improved HS graduation and substance use prevention, may improve long-term outcomes.


Assuntos
Diabetes Mellitus , Transplante de Fígado , Transtornos Relacionados ao Uso de Substâncias , Adulto , Humanos , Criança , Transplante de Fígado/efeitos adversos , Sobrevivência de Enxerto , Estudos Retrospectivos , Rejeição de Enxerto/epidemiologia , Fatores de Risco , Adesão à Medicação , Diabetes Mellitus/etiologia , Transtornos Relacionados ao Uso de Substâncias/etiologia , Transplantados/psicologia
20.
Liver Transpl ; 28(12): 1899-1910, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35555876

RESUMO

With advances in surgical techniques, medical management, and more equitable allocation systems, children who receive a liver transplantation (LT) today can expect remarkable outcomes early after LT. However, beyond 1 year after transplant, attrition rates have not improved. We reviewed two separate eras (Era 1: January 1995-June 2004 vs. Era 2: July 2004-March 2018) of the Society of Pediatric Liver Transplantation registry to explore the evolution and associated factors contributing to late graft loss (LGL) and late mortality (LM). The fraction of long-term pediatric LT recipients surviving after 1 year with their first graft significantly improved (81.5% in Era 1 vs. 85.7% in Era 2; p < 0.0001). This improvement occurred despite significant changes in patient selection toward higher risk populations (p < 0.001) and without notable improvement in perioperative complications such as hepatic artery thrombosis (p = 0.24) and early posttransplant reoperation (p = 0.94) that have historically contributed to poor late-allograft outcomes. Improved outcomes were associated with changes in patient characteristics and perioperative practices, which subsequently impacted both early post-LT complications as well as other sequalae known to contribute to adverse events in long-term pediatric LT recipients. In conclusion, despite significant changes in patient selection toward higher risk populations, and without notable improvement in several perioperative complications known to contribute to poor late-allograft outcomes, significant improvements in LGL and a trend toward improvement in LM was seen in a more contemporary cohort of children receiving an LT.


Assuntos
Sobrevivência de Enxerto , Transplante de Fígado , Criança , Humanos , Transplante de Fígado/métodos , Reoperação , Fatores de Risco , Transplantados , Estudos Retrospectivos , Resultado do Tratamento
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