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1.
Nature ; 622(7982): 393-401, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37821590

RESUMO

Recent human decedent model studies1,2 and compassionate xenograft use3 have explored the promise of porcine organs for human transplantation. To proceed to human studies, a clinically ready porcine donor must be engineered and its xenograft successfully tested in nonhuman primates. Here we describe the design, creation and long-term life-supporting function of kidney grafts from a genetically engineered porcine donor transplanted into a cynomolgus monkey model. The porcine donor was engineered to carry 69 genomic edits, eliminating glycan antigens, overexpressing human transgenes and inactivating porcine endogenous retroviruses. In vitro functional analyses showed that the edited kidney endothelial cells modulated inflammation to an extent that was indistinguishable from that of human endothelial cells, suggesting that these edited cells acquired a high level of human immune compatibility. When transplanted into cynomolgus monkeys, the kidneys with three glycan antigen knockouts alone experienced poor graft survival, whereas those with glycan antigen knockouts and human transgene expression demonstrated significantly longer survival time, suggesting the benefit of human transgene expression in vivo. These results show that preclinical studies of renal xenotransplantation could be successfully conducted in nonhuman primates and bring us closer to clinical trials of genetically engineered porcine renal grafts.


Assuntos
Rejeição de Enxerto , Transplante de Rim , Macaca fascicularis , Suínos , Transplante Heterólogo , Animais , Humanos , Animais Geneticamente Modificados , Células Endoteliais/imunologia , Células Endoteliais/metabolismo , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Transplante de Rim/métodos , Polissacarídeos/deficiência , Suínos/genética , Transplante Heterólogo/métodos , Transgenes/genética
2.
Xenotransplantation ; 31(1): e12833, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37864433

RESUMO

BACKGROUND: Highly sensitized patients face many barriers to kidney transplantation, including higher rates of antibody-mediated rejection after HLA-incompatible transplant. IdeS, an endopeptidase that cleaves IgG nonspecifically, has been trialed as desensitization prior to kidney transplant, and successfully cleaves donor-specific antibody (DSA), albeit with rebound. METHODS: IdeS was generated and tested (2 mg/kg, IV) in two naïve and four allosensitized nonhuman primates (NHP). Peripheral blood samples were collected at regular intervals following IdeS administration. Total IgG, total IgM, and anti-CMV antibodies were quantified with ELISA, and donor-specific antibody (DSA) and anti-pig antibodies were evaluated using flow cytometric crossmatch. B cell populations were assessed using flow cytometry. RESULTS: IdeS successfully cleaved rhesus IgG in vitro. In allosensitized NHP, robust reduction of total, DSA, anti-pig, and anti-CMV IgG was observed within one day following IdeS administration. Rapid rebound of all IgG antibody populations was observed, with antibody levels returning to baseline around day 14 post-infusion. Total IgM level was not affected by IdeS. Interestingly, a comparable reduction in antibody populations was observed after the second dose of IdeS. However, we have not observed any significant modulation of B cell subpopulations after IdeS. CONCLUSIONS: This study evaluated efficacy of IdeS in the allosensitized NHP in IgG with various specificities, mirroring antibody kinetics in human patients. The efficacy of IdeS on preexisting anti-pig antibodies may be useful in clinical xenotransplantation. However, given the limitation of IdeS on its durability as a monotherapy, optimization of IdeS with other agents targeting the humoral response is further needed.


Assuntos
Rejeição de Enxerto , Isoanticorpos , Animais , Humanos , Macaca mulatta , Rejeição de Enxerto/prevenção & controle , Transplante Heterólogo , Imunossupressores/uso terapêutico , Imunoglobulina G , Imunoglobulina M , Antígenos HLA
3.
Am J Transplant ; 23(7): 904-919, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37054891

RESUMO

Porcine vascular endothelial cells (PECs) form a mechanistic centerpiece of xenograft rejection. Here, we determined that resting PECs release swine leukocyte antigen class I (SLA-I) but not swine leukocyte antigen class-II DR (SLA-DR) expressing extracellular vesicles (EVs) and investigated whether these EVs proficiently initiate xenoreactive T cell responses via direct xenorecognition and costimulation. Human T cells acquired SLA-I+ EVs with or without direct contact to PECs, and these EVs colocalized with T cell receptors. Although interferon gamma-activated PECs released SLA-DR+ EVs, the binding of SLA-DR+ EVs to T cells was sparse. Human T cells demonstrated low levels of proliferation without direct contact to PECs, but marked T cell proliferation was induced following exposure to EVs. EV-induced proliferation proceeded independent of monocytes/macrophages, suggesting that EVs delivered both a T cell receptor signal and costimulation. Costimulation blockade targeting B7, CD40L, or CD11a significantly reduced T cell proliferation to PEC-derived EVs. These findings indicate that endothelial-derived EVs can directly initiate T cell-mediated immune responses, and suggest that inhibiting the release of SLA-I EVs from organ xenografts has the potential to modify the xenograft rejection. We propose a secondary-direct pathway for T cell activation via xenoantigen recognition/costimulation by endothelial-derived EVs.


Assuntos
Células Endoteliais , Linfócitos T , Humanos , Suínos , Animais , Endotélio , Antígenos de Histocompatibilidade Classe I , Imunidade
4.
Xenotransplantation ; 30(2): e12794, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36880602

RESUMO

BACKGROUND: Recent years have seen major advancements in xenotransplantation: the first pig-to-human heart transplant, the development of a brain-dead recipient model for kidney xenotransplantation, and the registration of the first xenokidney clinical trial. The attitudes of patients with kidney disease or transplants on xenotransplantation and an assessment of their reservations and considerations regarding the technology are crucial to successful clinical translation and eventual widespread implementation. METHODS: This systematic review was registered through PROSPERO (CRD42022344581) prior to initiation of the study and reported using the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. We included studies that evaluated attitudes towards and willingness to undergo xenotransplantation in patients with end-stage renal disease (ESRD), including those who had already undergone transplantation. MEDLINE (via Ovid), Embase (via Elsevier), and Web of Science (via Clarivate) were searched from database inception to July 15, 2022 by an experienced medical librarian for studies on xenotransplantation and attitudes. Abstracts and full text were screened using Covidence software and data items regarding study methodology, patient demographics, and attitudes regarding xenotransplantation were extracted using Microsoft Excel. Risk of bias assessments were performed using the Critical Appraisal Skills Programmed and National Institute of Health study quality assessment tools. RESULTS: Of 1992 studies identified, 14 studies met the inclusion criteria. These studies were conducted across eight countries, four in the United States, for a total of 3114 patients on the kidney waitlist or with a kidney transplant. All patients were over 17 years old and 58% were male. Acceptance of a xenotransplant was assessed using surveys in 12 studies. Sixty-three percent (n = 1354) of kidney patients reported that they would accept a xenotransplant with function comparable to that of an allotransplant. Acceptance of xenografts with inferior function to allografts (15%) or as bridge organs (35%) to allotransplantation was lower. Specific concerns expressed by patients included graft function, infection, social stigma, and animal rights. Subgroup analyses showed higher acceptance in already transplanted compared to waitlist patients and white compared to Black Americans. CONCLUSION: An understanding of patient attitudes and reservations is key to the successful execution of the first xenotransplantation clinical trials. This study compiles important factors to consider, such as patient concerns, attitudes regarding practical clinical scenarios for the use of xenotransplantation, and the impact of demographic factors on acceptance of this emerging technology.


Assuntos
Transplante de Coração , Nefropatias , Transplante de Rim , Humanos , Masculino , Animais , Suínos , Adolescente , Feminino , Transplante Heterólogo , Atitude , Transplante de Rim/métodos
5.
Anesth Analg ; 136(3): 518-523, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36729887

RESUMO

BACKGROUND: Hyperfibrinolysis is a possible complication during liver transplantation, particularly immediately after reperfusion. METHODS: We performed a retrospective study to examine the incidence, treatment, and resolution of postreperfusion hyperfibrinolysis in patients undergoing liver transplantation at Duke University Hospital from 2015 to 2020. RESULTS: Out of 535 patients undergoing liver transplantation, 21 or 3.9%, 95% CI (2.5-5.9), had hyperfibrinolysis after reperfusion. Hyperfibrinolysis occurred in 16 of 511 (3.1%) patients receiving livers from DBD donors, 5 of 18 (27.8%) patients receiving livers from donation after circulatory death (DCD) donors, and 0 of 6 (0.0%) patients receiving livers from living donors. Fibrinolysis was treated with cryoprecipitate (12/21), a combination of cryoprecipitate and tranexamic acid (3/21), or neither (6/21) and resolved within several hours in all cases. CONCLUSIONS: Anesthesiologists should be aware of the possibility of postreperfusion hyperfibrinolysis in liver transplantation, particularly with DCD donors, and may consider treatment with cryoprecipitate or tranexamic acid. Further work is needed to identify any potential differences, such as faster resolution of fibrinolysis, between different treatment modalities.


Assuntos
Transplante de Fígado , Ácido Tranexâmico , Humanos , Transplante de Fígado/efeitos adversos , Estudos Retrospectivos , Incidência , Ácido Tranexâmico/uso terapêutico , Doadores Vivos , Sobrevivência de Enxerto , Morte
6.
West Afr J Med ; 40(8): 808-813, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37639332

RESUMO

BACKGROUND/OBJECTIVES: Healthcare professionals (HCPs) play a key role in the prevention of hepatitis B virus (HBV) infection. HCPs are expected to have adequate basic knowledge of HBV and readily uptake HBV vaccination as they are a high-risk group, especially those that have direct contact with blood and/or blood products. This study was aimed at assessing the knowledge of and vaccination uptake of HBV among HCPs in a Nigerian tertiary hospital. METHODS: This was a cross-sectional study in which self-administered questionnaires were used to obtain data from different categories of HCPs in a tertiary hospital. The associations between categorical variables were tested using Chi-square test and a P value of 0.05 or less was considered significant. RESULTS: A total of 355 HCPs comprising 149 medical doctors, 180 nurses and 26 laboratory scientists participated in the study. Majority (90.0%) of the respondents correctly identified blood and/or blood products transfusion, needle stick injury, sharing of sharps and vertical transmission as routes of HBV transmission. About 83.4% of the participants were aware that HBV could be transmitted through unprotected sex. However, 39.2% and 15.8% of the participants reported kissing and HBV vaccination as routes of transmission, respectively. Their knowledge and uptake of HBV vaccination was, however, good. CONCLUSION: While majority of the HCPs had good knowledge of the routes of HBV transmission, few still had misconceptions about the routes of transmission, a situation which may cause social discord in the society especially among closely related individuals and potentially result in poor uptake of the highly effective HBV vaccine.


CONTEXTE/OBJECTIFS: Les professionnels de la santé jouent un rôle clé dans la prévention de l'infection par le virus de l'hépatite B (VHB). On s'attend à ce qu'ils aient des connaissances de base suffisantes sur le VHB et qu'ils acceptent facilement la vaccination contre le VHB car ils constituent un groupe à haut risque, en particulier ceux qui sont en contact direct avec du sang et/ou des produits sanguins. Cette étude visait à évaluer les connaissances et l'acceptation de la vaccination contre le VHB parmi le personnel soignant d'un hôpital tertiaire nigérian. MÉTHODES: Il s'agit d'une étude transversale dans laquelle des questionnaires auto-administrés ont été utilisés pour recueillir des données auprès de différentes catégories de professionnels de la santé dans un hôpital tertiaire. Les associations entre les variables catégorielles ont été testées à l'aide du test du chi carré et une valeur P de 0,05 ou moins a été considérée comme significative. RÉSULTATS: Au total, 355 professionnels de la santé, dont 149 médecins, 180 infirmières et 26 laborantins, ont participé à l'étude. La majorité (90,0 %) des personnes interrogées ont correctement identifié la transfusion de sang et/ou de produits sanguins, les blessures par piqûre d'aiguille, le partage d'objets tranchants et la transmission verticale comme étant des voies de transmission du VHB. Environ 83,4 % des participants savaient que le VHB pouvait être transmis lors de rapports sexuels non protégés. Cependant, 39,2 % et 15,8 % des participants ont déclaré que le baiser et la vaccination contre le VHB étaient des voies de transmission, respectivement. Leur connaissance et leur participation à la vaccination contre le VHB étaient cependant bonnes. CONCLUSION: Alors que la majorité des professionnels de santé avaient une bonne connaissance des voies de transmission du VHB, quelques-uns avaient encore des idées fausses sur les voies de transmission, une situation qui peut causer des discordes sociales dans la société, en particulier parmi les personnes étroitement liées, et potentiellement entraîner une faible utilisation du vaccin hautement efficace contre le VHB. Mots-clés: Virus de l'hépatite B, Professionnels de la santé, Vaccination, Connaissances.


Assuntos
Vírus da Hepatite B , Hepatite B , Humanos , Nigéria , Estudos Transversais , Centros de Atenção Terciária , Hepatite B/prevenção & controle , Atenção à Saúde
7.
Am J Transplant ; 22 Suppl 4: 1-11, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36239200

RESUMO

Sensitized patients, those who had prior exposure to foreign human leukocyte antigens, are transplanted at lower rates due to challenges in finding suitable organs. Desensitization strategies have permitted highly sensitized patients to undergo kidney transplantation, albeit with higher rates of rejection. This study assesses targeting plasma cell and interleukin (IL)-6 receptor for desensitization in a sensitized nonhuman primate kidney transplantation model. All animals were sensitized using two sequential skin transplants from maximally major histocompatibility complex-mismatched donors. Carfilzomib (CFZ)/tocilizumab (TCZ) desensitization (N = 6) successfully decreased donor-specific antibody (DSA) titers and prevented the expansion of B cells compared to CFZ monotherapy (N = 3). Dual desensitization further delayed, but did not prevent humoral rebound, as evidenced by a delayed increase in post-kidney transplant DSA titers. Accordingly, CFZ/TCZ desensitization conferred a significant survival advantage over CFZ monotherapy. A trend toward increased T follicular helper cells was also observed in the dual therapy group along the same timeline as an increase in DSA and subsequent graft loss. Cytomegalovirus reactivation also occurred in the CFZ/TCZ group but was prevented with ganciclovir prophylaxis. In accordance with prior studies of CFZ-based dual desensitization strategies, the addition of IL-6 receptor blockade resulted in desensitization with further suppression of posttransplant humoral response compared to CFZ monotherapy.


Assuntos
Rejeição de Enxerto , Isoanticorpos , Animais , Humanos , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Dessensibilização Imunológica/métodos , Antígenos HLA , Receptores de Interleucina-6 , Primatas
8.
Ann Surg ; 276(5): 846-853, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35894433

RESUMO

OBJECTIVE: To define benchmark values for liver transplantation (LT) in patients with perihilar cholangiocarcinoma (PHC) enabling unbiased comparisons. BACKGROUND: Transplantation for PHC is used with reluctance in many centers and even contraindicated in several countries. Although benchmark values for LT are available, there is a lack of specific data on LT performed for PHC. METHODS: PHC patients considered for LT after Mayo-like protocol were analyzed in 17 reference centers in 2 continents over the recent 5-year period (2014-2018). The minimum follow-up was 1 year. Benchmark patients were defined as operated at high-volume centers (≥50 overall LT/year) after neoadjuvant chemoradiotherapy, with a tumor diameter <3 cm, negative lymph nodes, and with the absence of relevant comorbidities. Benchmark cutoff values were derived from the 75th to 25th percentiles of the median values of all benchmark centers. RESULTS: One hundred thirty-four consecutive patients underwent LT after completion of the neoadjuvant treatment. Of those, 89.6% qualified as benchmark cases. Benchmark cutoffs were 90-day mortality ≤5.2%; comprehensive complication index at 1 year of ≤33.7; grade ≥3 complication rates ≤66.7%. These values were better than benchmark values for other indications of LT. Five-year disease-free survival was largely superior compared with a matched group of nodal negative patients undergoing curative liver resection (n=106) (62% vs 32%, P <0.001). CONCLUSION: This multicenter benchmark study demonstrates that LT offers excellent outcomes with superior oncological results in early stage PHC patients, even in candidates for surgery. This provocative observation should lead to a change in available therapeutic algorithms for PHC.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Tumor de Klatskin , Transplante de Fígado , Benchmarking , Colangiocarcinoma/cirurgia , Humanos , Tumor de Klatskin/patologia , Tumor de Klatskin/cirurgia , Padrão de Cuidado
9.
J Neurophysiol ; 121(1): 140-151, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30461371

RESUMO

Transient receptor potential vanilloid type 1 (TRPV1) is a ligand-gated ion channel expressed in the peripheral and central nervous systems. TRPV1-dependent mechanisms take part in a wide range of physiological and pathophysiological pathways including the regulation of homeostatic functions. TRPV1 expression in the hypothalamus has been described as well as evidence that TRPV1-dependent excitatory inputs to hypothalamic preautonomic neurons are diminished in diabetic conditions. Here we aimed to determine the functional expression of TRPV1 in two hypothalamic nuclei known to be involved in the central control of metabolism and to test the hypothesis that TRPV1-expressing neurons receive TRPV1-expressing inputs. A mouse model (TRPV1Cre/tdTom) was generated to identify TRPV1-expressing cells and determine the cellular properties of TRPV1-expressing neurons in adult mice. Our study demonstrated the functional expression of TRPV1 in the dorsomedial hypothalamic nucleus and paraventricular nucleus in adult mice. Our findings revealed that a subset of TRPV1Cre/tdTom neurons receive TRPV1-expressing excitatory inputs, indicating direct interaction between TRPV1-expressing neurons. In addition, astrocytes likely play a role in the modulation of TRPV1-expressing neurons. In summary, this study identified specific hypothalamic regions where TRPV1 is expressed and functional in adult mice and the existence of direct connections between TRPV1Cre/tdTom neurons. NEW & NOTEWORTHY Transient receptor potential vanilloid type 1 (TRPV1) is expressed in the hypothalamus, and TRPV1-dependent regulation of preautonomic neurons is decreased in hyperglycemic conditions. Our study demonstrated functional expression of TRPV1 in two hypothalamic nuclei involved in the control of energy homeostasis. Our results also revealed that a subset of TRPV1-expressing neurons receive TRPV1-expressing excitatory inputs. These findings suggest direct interaction between TRPV1-expressing neurons.


Assuntos
Hipotálamo/metabolismo , Neurônios/metabolismo , Canais de Cátion TRPV/metabolismo , Animais , Astrócitos/citologia , Astrócitos/metabolismo , Dependovirus , Feminino , Hipotálamo/citologia , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Masculino , Potenciais da Membrana/fisiologia , Camundongos Transgênicos , Neurônios/citologia , Técnicas de Patch-Clamp , RNA Mensageiro/metabolismo , Canais de Cátion TRPV/genética , Técnicas de Cultura de Tecidos , Proteína Vermelha Fluorescente
10.
Retina ; 39(10): 1872-1879, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30005004

RESUMO

PURPOSE: To report on the diagnostic outcomes and safety of full diagnostic vitrectomy (FDV) with surgical posterior vitreous detachment induction for diagnosing vitritis of uncertain etiology. METHODS: Forty-nine patients underwent primary FDV using the cassette washings for histopathological analysis. In addition, an undiluted core vitreous sample was obtained for microbial analysis in suspected infective cases. Cases were retrospectively given a diagnosis of inflammatory, infective, or neoplastic based on the results at final follow-up and the outcome of primary FDV categorized as diagnostic or nondiagnostic. The success of FDV was evaluated in relation to the final diagnosis. The need for additional intraocular biopsies and intraoperative or postoperative complications was also recorded. RESULTS: Full diagnostic vitrectomy was diagnostic in 26/49 cases (53%) and nondiagnostic in 23 (47%). The diagnostic success rate was greatest in neoplastic (16/20, 80%) and infective cases (9/13, 69%). Seven cases (14%) required additional biopsies to establish the diagnosis, and in 15/49 cases (31%), no cause of vitritis was identified. Intraoperative retinal breaks occurred in 3/49 cases (6%) and retinal detachment in 1/49 cases (2%). Three of 49 cases (6%) developed transiently elevated intraocular pressure postoperatively. CONCLUSION: Full diagnostic vitrectomy in combination with an undiluted core vitreous biopsy for suspected infections is safe and effective at securing a diagnosis in vitritis, particularly in cases of neoplasia.


Assuntos
Acuidade Visual , Vitrectomia/métodos , Corpo Vítreo/patologia , Descolamento do Vítreo/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha Fina , Criança , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Corpo Vítreo/cirurgia , Descolamento do Vítreo/etiologia , Descolamento do Vítreo/cirurgia , Adulto Jovem
12.
Curr Opin Nephrol Hypertens ; 26(2): 97-104, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27930384

RESUMO

PURPOSE OF REVIEW: Endothelial dysfunction is an early feature of vascular disease induced by cardiovascular risk factors (CRFs). In growing populations with obesity, diabetes, hypertension, and heart failure, mineralocorticoid receptor antagonism improves endothelial function. This review summarizes recent advances in our understanding of the specific role of endothelial cell mineralocorticoid receptor in vascular function in health and disease. RECENT FINDINGS: Using transgenic mice with mineralocorticoid receptor expression specifically modulated in endothelial cells, recent studies support the emerging concept that while endothelial cell mineralocorticoid receptor may be protective in health, in the presence of CRFs, endothelial cell mineralocorticoid receptor activity contributes to endothelial dysfunction and progression of vascular disease. Proposed mechanisms include a role for endothelial cell mineralocorticoid receptor in decreased nitric oxide production and bioavailability, increased vascular oxidative stress, regulation of epithelial sodium channels that enhance vascular stiffness, and increased endothelial cell adhesion molecules promoting inflammation. The role of endothelial cell mineralocorticoid receptor may also depend on the sex, race, or vascular bed involved. SUMMARY: Recent advances support the idea that endothelial cell mineralocorticoid receptor is a mediator of the switch from vascular health to disease in response to CRFs. Further investigation of the molecular mechanism is underway to identify therapeutic interventions that will limit the detrimental effects of endothelial cell mineralocorticoid receptor in patients at cardiovascular risk.


Assuntos
Doenças Cardiovasculares/fisiopatologia , Endotélio Vascular/fisiopatologia , Receptores de Mineralocorticoides/fisiologia , Animais , Doenças Cardiovasculares/metabolismo , Endotélio Vascular/metabolismo , Humanos , Inflamação/metabolismo , Óxido Nítrico/metabolismo , Estresse Oxidativo , Receptores de Mineralocorticoides/metabolismo , Fatores de Risco , Transdução de Sinais , Rigidez Vascular
13.
J Neurophysiol ; 115(3): 1389-98, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26719086

RESUMO

Olanzapine, an atypical antipsychotic, is widely prescribed for the treatment of schizophrenia and bipolar disorder despite causing undesirable metabolic side effects. A variety of mechanisms and brain sites have been proposed as contributors to the side effects; however, the role of the dorsal motor nucleus of the vagus nerve (DMV), which plays a crucial role in the regulation of subdiaphragmatic organs and thus governs energy and glucose homeostasis, is largely unknown. Identifying the effect of olanzapine on the excitability of DMV neurons in both sexes is thus crucial to understanding possible underlying mechanisms. Whole cell patch-clamp electrophysiological recordings were conducted in stomach- and liver-related DMV neurons identified with retrograde viral tracers and in random DMV neurons. The effect of olanzapine on the neuronal excitability of DMV neurons both in male and female mice was established. Our data demonstrate that olanzapine hyperpolarizes the DMV neurons in both sexes and this effect is reversible. The hyperpolarization is associated with decreased firing rate and input resistance. Olanzapine also decreases the excitability of a subset of stomach- and liver-related DMV neurons. Our study demonstrates that olanzapine has a powerful effect on DMV neurons in both sexes, indicating its ability to reduce vagal output to the subdiaphragmatic organs, which likely contributes to the metabolic side effects observed in both humans and experimental models. These findings suggest that the metabolic side effects of olanzapine may partially originate in the DMV.


Assuntos
Antipsicóticos/efeitos adversos , Benzodiazepinas/efeitos adversos , Tronco Encefálico/efeitos dos fármacos , Potenciais de Ação , Animais , Tronco Encefálico/fisiologia , Feminino , Fígado/inervação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/fisiologia , Olanzapina , Estômago/inervação , Nervo Vago/efeitos dos fármacos , Nervo Vago/fisiologia
14.
Ophthalmology ; 121(2): 492-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24314841

RESUMO

PURPOSE: Quantifying the extent of conjunctival fibrosis for documentation of progression in conjunctival scarring disease is a clinical challenge. Measurement of forniceal foreshortening facilitates monitoring of these disorders. This study aims (1) to define the limits of the normal human conjunctival fornices and how these alter with age and (2) to provide normative data for upper and lower fornix depths (FDs) and fornix intercanthal distance (FICD) within a healthy South Asian, racially distinct population. DESIGN: Epidemiologic, cross-sectional study. PARTICIPANTS: A total of 240 subjects with national origins from South Asia, with no known ocular history and normal adnexal and conjunctival examination, aged 20 to 80 years. METHODS: An FICD modification of a custom-designed fornix depth measurer (FDM) was validated and used for measurement of both lower and upper FDs together with FICDs in 480 healthy eyes with no ocular comorbidities. Data were analyzed using repeated-measures analysis of variance and presented as means with 95% confidence intervals (CIs). MAIN OUTCOME MEASURES: Mean lower and upper FDs and FICD for the entire cohort, stratified according to age decade and sex. RESULTS: For this South Asian population, the overall upper and lower FDs were 15.3 mm (95% CI, 14.9-15.6) and 10.9 mm (95% CI, 10.7-11.1), respectively, with FICD defined as 32.9 mm (95% CI, 32.5-33.4) (upper) and 31.7 mm (95% CI, 31.3-32.1) (lower). With increasing age, a progressive reduction of all measured parameters (P < 0.001) was noted, with female subjects having significantly shallower fornices (upper FD, P < 0.001; lower FD, P < 0.001; upper FICD, P = 0.081; and lower FICD, P = 0.015). CONCLUSIONS: This is the first study to define the limits of normal upper FD and FICDs in any population group. Our study demonstrates sex variations and progressive conjunctival shrinkage with age. Although it provides important, objective data for normal forniceal anatomy, further study is recommended in other populations to confirm the generalizability of these data or to enable normal comparative datasets for the assessment of conjunctival scarring disorders among all anthropological groups.


Assuntos
Envelhecimento/fisiologia , Povo Asiático , Túnica Conjuntiva/anatomia & histologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Ásia , Estudos Transversais , Estudos Epidemiológicos , Pálpebras/anatomia & histologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valores de Referência , Distribuição por Sexo , Adulto Jovem
15.
Am J Obstet Gynecol ; 210(6): 567.e1-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24412118

RESUMO

OBJECTIVE: We sought to determine the attributes of successful and unsuccessful fellowship applicants of the American Board of Obstetrics and Gynecology Inc (ABOG)-approved fellowship programs and to identify salient differences between subspecialty applicants. STUDY DESIGN: Anonymous questionnaires were completed by obstetrics and gynecology fellowship applicants using a web-based survey after match day of 2012. Fellowship applicant practices were evaluated and included importance of prematch preparations, interview process, networking practices, and postmatch reflections. RESULTS: A total of 327 fellowship applicants applying to programs accredited by the ABOG were surveyed, and 200 completed the survey (61% response rate). A comparison between prematch educational preparations pursued by applicants showed that matched applicants were more likely to come from allopathic medical schools (94%), attain membership in Alpha Omega Alpha and/or Phi Beta Kappa (27%), and receive a letter of recommendation from a nationally known subspecialist (77%) than unmatched applicants (P = .03, .005, and .007, respectively). Applicants to reproductive endocrinology and infertility were more likely than female pelvic medicine and reconstructive surgery to be members of academic honor societies (P = .008). Research publication was common among matched subspecialist applicants, with over half publishing 1-3 peer-reviewed manuscripts prior to matching. Applicants to gynecologic oncology did more visiting electives than any other specialty applicants (P < .001). CONCLUSION: Successful obstetrics and gynecology fellowship applicants have superior prematch preparations, strong letters of recommendation from leaders in their field of interest, and multiple research publications. These data will guide applicants to a critical self-analysis before deciding to apply.


Assuntos
Educação de Pós-Graduação em Medicina/estatística & dados numéricos , Bolsas de Estudo/estatística & dados numéricos , Ginecologia/educação , Obstetrícia/educação , Bolsas de Estudo/classificação , Feminino , Humanos , Masculino , Conselhos de Especialidade Profissional , Inquéritos e Questionários , Estados Unidos
16.
Regen Med ; : 1-10, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39387455

RESUMO

Tennis elbow, also commonly known as lateral epicondylitis or common extensor tendinosis, is a common musculoskeletal injury in the adult population. Currently, the standard treatment regimen prescribed for this injury involves a combination of rest, physical therapy, bracing and anti-inflammatory medications. If refractory to these conservative measures, platelet-rich plasma has been shown effective. However, in the case of full thickness tears, surgery has remained the only treatment option until now. We present a case report of a 56-year-old man with a diagnosis of a left large full thickness tear and rupture with retraction of his common extensor tendon (CET) following a corticosteroid injection. The patient was treated with microfragmented adipose transfer. He was re-evaluated around 7 weeks and again at 15 weeks post-treatment and demonstrated ultrasound evidence of complete bridging and remodeling of his prior full thickness CET tear and resolution of retraction. This case presents a promising option for patients with full thickness CET tears who would like to refrain from or are unable to have surgery. Further research and possible randomized controlled trials are needed to further assess the full efficacy of microfragmented adipose transfer in the treatment of full thickness CET tears.


Adipose cells from a patient's own body fat are one of the best sources of mesenchymal stem cells (MSC) and growth factors that contribute to the generation of collagen protein fibers. MSC's are versatile cells that can differentiate into a variety of cell types, while collagen is an important component of muscles and tendons, as it provides structure. MSC's can be harvested from one's own fat and then used to help supplement the body's natural repair process of a variety of injured tissues. This case presents a patient with a history of persistent elbow pain caused by a large full-thickness tear and rupture of the common extensor tendon (CET) of the elbow. Full thickness tears are large deep tears that extend across the entirety of the tendon. Generally, partial CET tears of varying severities are some of the most common tendon injuries seen in the elbow and are injuries that historically, are treated with conservative management, such as pain medication, cortisone injection, physical therapy, platelet-rich plasma or surgery once/if conservative interventions fail. Full thickness tears, however, usually require surgery for patients to feel better. In this case, the patient underwent a novel regenerative treatment alternative to surgery, known as microfragmented adipose transfer (MFAT), to repair the torn CET. Fat was harvested from his flanks, was washed and cleaned, then injected into the CET tear of the elbow. He experienced significant improvements in function and pain and tendon healing was documented using ultrasound and MRI imaging. This case supports using MFAT for lateral elbow pain caused by full-thickness CET tears as a novel and significantly less invasive method than surgery. Our case illustrates the need for more research and possible clinical trials evaluating MFAT as a treatment option for common musculoskeletal pathologies.

17.
Nat Commun ; 15(1): 6854, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39127732

RESUMO

Therapeutic apheresis aims to selectively remove pathogenic substances, such as antibodies that trigger various symptoms and diseases. Unfortunately, current apheresis devices cannot handle small blood volumes in infants or small animals, hindering the testing of animal model advancements. This limitation restricts our ability to provide treatment options for particularly susceptible infants and children with limited therapeutic alternatives. Here, we report our solution to these challenges through an acoustofluidic-based therapeutic apheresis system designed for processing small blood volumes. Our design integrates an acoustofluidic device with a fluidic stabilizer array on a chip, separating blood components from minimal extracorporeal volumes. We carried out plasma apheresis in mouse models, each with a blood volume of just 280 µL. Additionally, we achieved successful plasmapheresis in a sensitized mouse, significantly lowering preformed donor-specific antibodies and enabling desensitization in a transplantation model. Our system offers a new solution for small-sized subjects, filling a critical gap in existing technologies and providing potential benefits for a wide range of patients.


Assuntos
Remoção de Componentes Sanguíneos , Plasmaferese , Animais , Remoção de Componentes Sanguíneos/instrumentação , Remoção de Componentes Sanguíneos/métodos , Camundongos , Plasmaferese/instrumentação , Plasmaferese/métodos , Humanos , Dispositivos Lab-On-A-Chip , Feminino , Acústica/instrumentação
18.
HLA ; 104(1): e15599, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39041289

RESUMO

Xenotransplantation is a potential option for individuals for whom an acceptable human allograft is unavailable. Individuals with broadly reactive HLA antibodies due to prior exposure to foreign HLA are potential candidates for a clinical xenotransplant trial. It remains controversial if allosensitisation results in the development of cross-reactive antibodies against SLA. This may require increased histocompatibility scrutiny for highly sensitised individuals prior to enrollment in a clinical trial. Serum samples were obtained from non-human primates sensitised via serial skin transplantation from maximally MHC-mismatched donor, as reported. Sera from pre- and post-allosensitisation timepoints were assessed in a flow crossmatch (FXM) for IgM and IgG binding to pig splenocytes with or without red blood cell adsorption. Xenoreactive antibodies were eluted from pig splenocytes and screened on a single antigen HLA bead assay. A MHC Matchmaker algorithm was developed to predict potential conserved amino acid motifs among the pig, NHP, and human. Our sensitised NHP model was used to demonstrate that allosensitisation does not result in an appreciable difference in xenoreactive antibody binding in a cell-based FXM. However, antibody elution and screening on single antigen HLA beads suggest the existence of potential cross-reactive antibodies against SLA. The cross-reactive IgG after allosensitisation were predicted by comparing the recipient Mamu alleles against its previous allograft donor Mamu alleles and the donor pig SLA alleles. Our study suggests that allosensitisation could elevate cross-reactive antibodies, but a more sensitive assay than a cell-based FXM is required to detect them. The MHC Matchmaker algorithm was developed as a potential tool to help determine amino acid motif conservation and reactivity pattern.


Assuntos
Reações Cruzadas , Citometria de Fluxo , Antígenos de Histocompatibilidade Classe I , Teste de Histocompatibilidade , Animais , Humanos , Reações Cruzadas/imunologia , Teste de Histocompatibilidade/métodos , Citometria de Fluxo/métodos , Suínos , Antígenos de Histocompatibilidade Classe I/imunologia , Imunoglobulina G/imunologia , Imunoglobulina G/sangue , Isoanticorpos/imunologia , Isoanticorpos/sangue , Transplante Heterólogo , Antígenos de Histocompatibilidade Classe II/imunologia , Transplante de Pele , Imunoglobulina M/imunologia , Imunoglobulina M/sangue , Antígenos HLA/imunologia , Linfócitos/imunologia , Algoritmos
19.
Front Microbiol ; 15: 1413250, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39104592

RESUMO

Chikungunya virus (CHIKV), a single-stranded RNA virus transmitted by Aedes mosquitoes, poses a significant global health threat, with severe complications observed in vulnerable populations. The only licensed vaccine, IXCHIQ, approved by the US FDA, is insufficient to address the growing disease burden, particularly in endemic regions lacking herd immunity. Monoclonal antibodies (mAbs), explicitly targeting structural proteins E1/E2, demonstrate promise in passive transfer studies, with mouse and human-derived mAbs showing protective efficacy. This article explores various vaccine candidates, including live attenuated, killed, nucleic acid-based (DNA/RNA), virus-like particle, chimeric, subunit, and adenovirus vectored vaccines. RNA vaccines have emerged as promising candidates due to their rapid response capabilities and enhanced safety profile. This review underscores the importance of the E1 and E2 proteins as immunogens, emphasizing their antigenic potential. Several vaccine candidates, such as CHIKV/IRES, measles vector (MV-CHIK), synthetic DNA-encoded antibodies, and mRNA-lipid nanoparticle vaccines, demonstrate encouraging preclinical and clinical results. In addition to identifying potential molecular targets for antiviral therapy, the study looks into the roles played by Toll-like receptors, RIG-I, and NOD-like receptors in the immune response to CHIKV. It also offers insights into novel tactics and promising vaccine candidates. This article discusses potential antiviral targets, the significance of E1 and E2 proteins, monoclonal antibodies, and RNA vaccines as prospective Chikungunya virus vaccine candidates.

20.
J Gastrointest Surg ; 28(5): 738-745, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38704208

RESUMO

BACKGROUND: Liver transplantation (LT) has been shown to be superior to resection in highly selected patients with perihilar cholangiocarcinoma (CCA), yet has traditionally been contraindicated for intrahepatic CCA (iCCA). Herein, we aimed to examine contemporary trends and outcomes for surgical resection and LT for iCCA. METHODS: The National Cancer Database was queried for patients presenting with stage I-III iCCA between 2010 and 2018 who underwent resection or LT. Overall survival (OS) was compared with Kaplan-Meier and multivariable Cox proportional hazards methods stratified by management. Secondary analysis of patients undergoing transplant for CCA was performed with the United Network for Organ Sharing database. RESULTS: Of 2565 patients, 2412 (94.0%) underwent resection and 153 (5.96%) LT of whom 84 (54.9%) received neoadjuvant therapy. Utilization of LT remained between 3.9% and 7.8% annually. Unadjusted 5-year OS was higher for LT than resection (59.8% vs 39.9%, P = .0067), yet adjusted analysis revealed no significant difference in mortality (hazard ratio, 0.91; 95% CI, 0.66-1.27; P = .58). On secondary analysis including 437 patients with all subtypes of CCA, unadjusted 5-year OS was higher for non-CCA indications (79% vs 52%-54%, P < .001). CONCLUSION: Utilization of LT for iCCA remains low and many cases are likely incidental. Although partial hepatectomy remains the standard of care for patients with resectable disease, our findings suggest that highly selected patients with unresectable iCCA may achieve favorable outcomes after LT. Granular, prospective data are needed to identify patients most likely to benefit from transplant and allocate scarce liver grafts.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Hepatectomia , Transplante de Fígado , Humanos , Transplante de Fígado/estatística & dados numéricos , Masculino , Feminino , Neoplasias dos Ductos Biliares/cirurgia , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/patologia , Pessoa de Meia-Idade , Idoso , Colangiocarcinoma/cirurgia , Colangiocarcinoma/mortalidade , Colangiocarcinoma/patologia , Resultado do Tratamento , Terapia Neoadjuvante/estatística & dados numéricos , Taxa de Sobrevida , Bases de Dados Factuais , Modelos de Riscos Proporcionais , Estimativa de Kaplan-Meier , Estudos Retrospectivos , Estadiamento de Neoplasias
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