Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 471
Filtrar
1.
Clin Transplant ; 38(7): e15413, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39033508

RESUMO

INTRODUCTION: It is unclear whether kidney/pancreas (KP) transplantation will prevent the progression of peripheral arterial disease (PAD) in patients with insulin dependent diabetes (IDDM) and end-stage renal disease. We sought to determine the pre- and posttransplant prevalence of symptomatic PAD and changes in carotid artery intima-media thickness (IMT) in KP recipients. METHODS: In this single center study, outcomes were compared between KP recipients with and without a history of PAD. A subset of recipients underwent pre- and posttransplant IMT measurements. RESULTS: Among the study group (N = 107), 18 (17%) recipients admitted to a pretransplant history of symptomatic PAD, comprised 11 foot infections and 7 amputations (5 minor and 2 major). Baseline characteristics of age, gender, race, years of diabetes, dialysis history, smoking history, years of hypertension, and history of coronary artery disease (CAD) were equivalent between PAD and non-PAD cohorts. At a median follow-up of 60 months (IQR: 28, 110), 16 (15%) KP recipients had suffered a PAD event. In multivariate analysis, a pretransplant history of PAD (hazard ratio [HR] 9.66, p < 0.001) and CAD (HR 3.33, p = 0.04) were independent predictors of posttransplant PAD events. Among a subset of 20 recipients (3 with PAD), mean IMT measurements pretransplant and at a median of 24 (range 18-24) months posttransplant, showed no evidence of disease progression. CONCLUSION: Based on IMT measurements and clinical results, KP transplantation stabilized PAD in most patients, but did not alter outcomes of symptomatic PAD recipients. A pretransplant history of PAD and CAD was an independent predictor of posttransplant PAD events.


Assuntos
Espessura Intima-Media Carotídea , Falência Renal Crônica , Transplante de Rim , Transplante de Pâncreas , Doença Arterial Periférica , Humanos , Feminino , Masculino , Transplante de Pâncreas/efeitos adversos , Doença Arterial Periférica/cirurgia , Doença Arterial Periférica/etiologia , Pessoa de Meia-Idade , Seguimentos , Transplante de Rim/efeitos adversos , Falência Renal Crônica/cirurgia , Fatores de Risco , Prognóstico , Diabetes Mellitus Tipo 1/cirurgia , Diabetes Mellitus Tipo 1/complicações , Adulto , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Taxa de Filtração Glomerular , Testes de Função Renal
2.
ACS Omega ; 9(22): 23782-23792, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38854584

RESUMO

In this study, we conducted first-principles calculations interfaced with Boltzmann transport theory to examine the carrier-dependent thermoelectric properties of CrS2-x Te x (x: 0, 1, 2) dichalcogenides monolayers. We conducted a systematic analysis of the structural, phonon band structures, elastic properties, electronic structures, and thermoelectric properties, of electron (e) and hole (h) doped CrS2-x Te x (x: 0, 1, 2) dichalcogenides monolayers. The studied 2D TMDCs exhibit structural stability, as indicated by the negative formation energy. Additionally, the phonon band structures indicate no negative frequencies along any wave vector, confirming the dynamic stability of the CrS2-x Te x monolayers. CrS2 and CrTe2 monolayers are semiconductors with direct bandgaps of 1.01 and 0.67 eV, respectively. A Janus CrSTe monolayer has a smaller bandgap of 0.21 eV. Temperatures range between 300 and 500 K, and concentrations of e(h) doped in the range of 1.0 × 1018-1.0 × 1020 cm-3 are used to compute the thermoelectric transport coefficients. The low lattice thermal conductivity is predicted for the studied compounds, among which Janus CrSTe and CrTe2 have the minimum value of κlat ≈ 1 W/mK @ 700 K. The figure-of-merit ZT projected value at the optimal e(h) doping concentration for the CrS2 monolayer is as high as 0.07 (0.09) at 500 K. Our findings demonstrate how to design improved thermoelectric materials suitable for various thermoelectric devices.

3.
Heliyon ; 10(10): e30927, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38779003

RESUMO

The purpose of this study was to synthesize ecofriendly nano-composite in which agricultural waste (seeds of Tamarindus indica) was used to synthesize tamarind seed polysaccharides (TSP) and its composite with copper nanoparticles (Cu-NPs) for the purpose of green and clean environment as well as reduction of green-house gases. Confirmation of extracted TSP, synthesized nanocomposite was carried out using FTIR, SEM, PXRD and EDX techniques. In FTIR analysis TSP gives a strong broad peak at 3331 cm-1 due to -OH group and in case of composite its intensity is reduced which might be due to the interactions between -OH and Cu+2 ions. SEM analysis gives that TSP have irregular and rough surface while Cu-NPs exhibited spherical morphology and composite showed clustering of spherical shape to rough surface. EDX analysis quantitatively represented copper having atomic ratio 0.57 % which confirms the synthesis of composite. Furthermore, synthesized composite demonstrated excellent antibacterial activity against gram-positive (S.aureus) and gram-negative bacteria (E.coli) even greater than standard medicine (ciprofloxacin). From this study it was revealed that agriculture waste can be utilized to make environment green as well as synthesized composite from agricultural waste seed also displayed excellent antimicrobial activities which directs that they can be utilized in medical field. This study aims to assess the antimicrobial properties of the nanocomposite, aiming to contribute to the development of effective antimicrobial agents. Through these objectives, the research seeks to bridge the gap between green technology and antimicrobial efficacy, offering a promising avenue for both environmental conservation and healthcare advancements.

4.
Transplant Direct ; 10(4): e1590, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38464428

RESUMO

Background: The COVID-19 pandemic has led to an increase in SARS-CoV-2-test positive potential organ donors. The benefits of life-saving liver transplantation (LT) must be balanced against the potential risk of donor-derived viral transmission. Although emerging evidence suggests that the use of COVID-19-positive donor organs may be safe, granular series thoroughly evaluating safety are still needed. Results of 29 consecutive LTs from COVID-19-positive donors at a single center are presented here. Methods: A retrospective cohort study of LT recipients between April 2020 and December 2022 was conducted. Differences between recipients of COVID-19-positive (n = 29 total; 25 index, 4 redo) and COVID-19-negative (n = 472 total; 454 index, 18 redo) deceased donor liver grafts were compared. Results: COVID-19-positive donors were significantly younger (P = 0.04) and had lower kidney donor profile indices (P = 0.04) than COVID-19-negative donors. Recipients of COVID-19-positive donor grafts were older (P = 0.04) but otherwise similar to recipients of negative donors. Donor SARS-CoV-2 infection status was not associated with a overall survival of recipients (hazard ratio, 1.11; 95% confidence interval, 0.24-5.04; P = 0.89). There were 3 deaths among recipients of liver grafts from COVID-19-positive donors. No death seemed virally mediated because there was no qualitative association with peri-LT antispike antibody titers, post-LT prophylaxis, or SARS-CoV-2 variants. Conclusions: The utilization of liver grafts from COVID-19-positive donors was not associated with a decreased overall survival of recipients. There was no suggestion of viral transmission from donor to recipient. The results from this large single-center study suggest that COVID-19-positive donors may be used safely to expand the deceased donor pool.

5.
J Endocrinol ; 261(1)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38305305

RESUMO

Metabolic syndrome (MetS) is an increasing global health threat and strong risk factor for type 2 diabetes (T2D). MetS causes both hyperinsulinemia and islet size overexpansion, and pancreatic ß-cell failure impacts insulin and proinsulin secretion, mitochondrial density, and cellular identity loss. The low-density lipoprotein receptor knockout (LDLr-/-) model combined with high-fat diet (HFD) has been used to study alterations in multiple organs, but little is known about the changes to ß-cell identity resulting from MetS. Osteocalcin (OC), an insulin-sensitizing protein secreted by bone, shows promising impact on ß-cell identity and function. LDLr-/- mice at 12 months were fed chow or HFD for 3 months ± 4.5 ng/h OC. Islets were examined by immunofluorescence for alterations in nuclear Nkx6.1 and PDX1 presence, insulin-glucagon colocalization, islet size and %ß-cell and islet area by insulin and synaptophysin, and mitochondria fluorescence intensity by Tomm20. Bone mineral density (BMD) and %fat changes were examined by Piximus Dexa scanning. HFD-fed mice showed fasting hyperglycemia by 15 months, increased weight gain, %fat, and fasting serum insulin and proinsulin; concurrent OC treatment mitigated weight increase and showed lower proinsulin-to-insulin ratio, and higher BMD. HFD increased %ß and %islet area, while simultaneous OC-treatment with HFD was comparable to chow-fed mice. Significant reductions in nuclear PDX1 and Nkx6.1 expression, increased insulin-glucagon colocalization, and reduction in ß-cell mitochondria fluorescence intensity were noted with HFD, but largely prevented with OC administration. OC supplementation here suggests a benefit to ß-cell identity in LDLr-/- mice and offers intriguing clinical implications for countering metabolic syndrome.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperinsulinismo , Células Secretoras de Insulina , Ilhotas Pancreáticas , Síndrome Metabólica , Animais , Camundongos , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica/efeitos adversos , Glucagon/metabolismo , Hiperinsulinismo/metabolismo , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Lipoproteínas LDL , Síndrome Metabólica/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteocalcina/metabolismo , Proinsulina/metabolismo , Aumento de Peso
6.
Nat Immunol ; 25(1): 66-76, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38168955

RESUMO

CD4+ T cells are central to various immune responses, but the molecular programs that drive and maintain CD4+ T cell immunity are not entirely clear. Here we identify a stem-like program that governs the CD4+ T cell response in transplantation models. Single-cell-transcriptomic analysis revealed that naive alloantigen-specific CD4+ T cells develop into TCF1hi effector precursor (TEP) cells and TCF1-CXCR6+ effectors in transplant recipients. The TCF1-CXCR6+CD4+ effectors lose proliferation capacity and do not reject allografts upon adoptive transfer into secondary hosts. By contrast, the TCF1hiCD4+ TEP cells have dual features of self-renewal and effector differentiation potential, and allograft rejection depends on continuous replenishment of TCF1-CXCR6+ effectors from TCF1hiCD4+ TEP cells. Mechanistically, TCF1 sustains the CD4+ TEP cell population, whereas the transcription factor IRF4 and the glycolytic enzyme LDHA govern the effector differentiation potential of CD4+ TEP cells. Deletion of IRF4 or LDHA in T cells induces transplant acceptance. These findings unravel a stem-like program that controls the self-renewal capacity and effector differentiation potential of CD4+ TEP cells and have implications for T cell-related immunotherapies.


Assuntos
Regulação da Expressão Gênica , Linfócitos T Reguladores , Diferenciação Celular
7.
J Am Soc Nephrol ; 35(3): 347-360, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38147137

RESUMO

SIGNIFICANCE STATEMENT: There is no standardized desensitization regimen for kidney transplant candidates. CD38, expressed by plasma cells, could be targeted for desensitization to deplete plasma cells producing alloantibodies and donor-specific antibodies. Few studies and case reports are available regarding the use of CD38 antibodies for desensitization in patients awaiting kidney transplant. This study shows that isatuximab, a CD38-targeting therapy, was well tolerated in kidney transplant candidates, with a durable decrease in anti-HLA antibodies and partial desensitization activity. The short treatment period and long follow-up of this study allowed for the understanding of the mechanism and timing for any antibody rebound. Isatuximab could be further investigated as an option for adjunct therapy to existing desensitization for patients on the kidney transplant waitlist. BACKGROUND: Patients with calculated panel reactive antibody (cPRA) ≥80.00%, particularly those with cPRA ≥99.90%, are considered highly sensitized and underserved by the Kidney Allocation System. Desensitization removes circulating reactive antibodies and/or suppresses antibody production to increase the chances of a negative crossmatch. CD38 is expressed highly on plasma cells, thus is a potential target for desensitization. METHODS: This was an open-label single-arm phase 1/2 study investigating the safety, pharmacokinetics, and preliminary efficacy of isatuximab in patients awaiting kidney transplantation. There were two cohorts, cohorts A and B, which enrolled cPRA ≥99.90% and 80.00% to <99.90%, respectively. RESULTS: Twenty-three patients (12 cohort A, 11 cohort B) received isatuximab 10 mg/kg weekly for 4 weeks then every 2 weeks for 8 weeks. Isatuximab was well tolerated with pharmacokinetic and pharmacodynamic profiles that indicated similar exposure to multiple myeloma trials. It resulted in decreases in CD38 + plasmablasts, plasma cells, and NK cells and significant reductions in HLA-specific IgG-producing memory B cells. Overall response rate, on the basis of a predefined composite desensitization end point, was 83.3% and 81.8% in cohorts A and B. Most responders had decreases in anti-HLA antibodies that were maintained for 26 weeks after the last dose. Overall, cPRA values were minimally affected, however, with only 9/23 patients (39%) having cPRA decreases to target levels. By study cutoff (median follow-up of 68 weeks), six patients received transplant offers, of which four were accepted. CONCLUSIONS: In this open-label trial, isatuximab was well tolerated and resulted in a durable decrease in anti-HLA antibodies with partial desensitization activity. CLINICAL TRIAL REGISTRATION NUMBER: NCT04294459 .


Assuntos
Transplante de Rim , Humanos , Anticorpos Monoclonais Humanizados , Rim , Isoanticorpos , Soro Antilinfocitário
8.
Cancers (Basel) ; 15(22)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38001597

RESUMO

Transplant oncology is an emerging concept of cancer treatment with a promising prospective outcome. The applications of oncology, transplant medicine, and surgery are the core of transplant oncology to improve patients' survival and quality of life. The main concept of transplant oncology is to radically cure cancer by removing the diseased organ and replacing it with a healthy one, aiming to improve the survival outcomes and quality of life of cancer patients. Subsequently, it seeks to expand the treatment options and research for hepatobiliary malignancies, which have seen significantly improved survival outcomes after the implementation of liver transplantation (LT). In the case of colorectal cancer (CRC) in the transplant setting, where the liver is the most common site of metastasis of patients who are considered to have unresectable disease, initial studies have shown improved survival for LT treatment compared to palliative therapy interventions. The indications of LT for hepatobiliary malignancies have been slowly expanded over the years beyond Milan criteria in a stepwise manner. However, the outcome improvements and overall patient survival are limited to the specifics of the setting and systematic intervention options. This review aims to illustrate the representative concepts and history of transplant oncology as an emerging discipline for the management of hepatobiliary malignancies, in addition to other emerging concepts, such as the uses of immunotherapy in a peri-transplant setting as well as the use of circulating tumor DNA (ctDNA) for surveillance post-transplantation.

9.
Am J Transplant ; 23(12): 1980-1989, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37748554

RESUMO

Older compatible living donor kidney transplant (CLDKT) recipients have higher mortality and death-censored graft failure (DCGF) compared to younger recipients. These risks may be amplified in older incompatible living donor kidney transplant (ILDKT) recipients who undergo desensitization and intense immunosuppression. In a 25-center cohort of ILDKT recipients transplanted between September 24, 1997, and December 15, 2016, we compared mortality, DCGF, delayed graft function (DGF), acute rejection (AR), and length of stay (LOS) between 234 older (age ≥60 years) and 1172 younger (age 18-59 years) recipients. To investigate whether the impact of age was different for ILDKT recipients compared to 17 542 CLDKT recipients, we used an interaction term to determine whether the relationship between posttransplant outcomes and transplant type (ILDKT vs CLDKT) was modified by age. Overall, older recipients had higher mortality (hazard ratio: 1.632.072.65, P < .001), lower DCGF (hazard ratio: 0.360.530.77, P = .001), and AR (odds ratio: 0.390.540.74, P < .001), and similar DGF (odds ratio: 0.461.032.33, P = .9) and LOS (incidence rate ratio: 0.880.981.10, P = 0.8) compared to younger recipients. The impact of age on mortality (interaction P = .052), DCGF (interaction P = .7), AR interaction P = .2), DGF (interaction P = .9), and LOS (interaction P = .5) were similar in ILDKT and CLDKT recipients. Age alone should not preclude eligibility for ILDKT.


Assuntos
Transplante de Rim , Humanos , Idoso , Pessoa de Meia-Idade , Adolescente , Adulto Jovem , Adulto , Transplante de Rim/efeitos adversos , Doadores Vivos , Sobrevivência de Enxerto , Rejeição de Enxerto/etiologia , Antígenos HLA , Fatores de Risco
10.
Microb Cell Fact ; 22(1): 148, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37559084

RESUMO

Colorectal cancer (CRC) is the third cause of death by cancers worldwide and is one of the most common cancer types reported in both Egypt and the United States. The use of probiotics as a dietary therapy is increasing either as a prevention or as a treatment for many diseases, particularly, in the case of CRC. The increasing acceptance of lactic acid bacterial (LAB) oligosaccharides as bioactive agents has led to an increase in the demand for the large-scale production of LAB-oligosaccharides using fermentation technology. Therefore, in the current study, we are using the Plackett- Burman design (PBD) approach, where sixteen experimental trials were applied to optimize the production of the target oligosaccharide LA-EPS-20079 from Lactobacillus acidophilus. Glucose, yeast extract and sodium acetate trihydrate were the top three significant variables influencing LA-EPS production. The maximum concentration of LA-EPS-20079 achieved by L. acidophilus was 526.79 µg/ml. Furthermore, Box-Behnken design (BBD) as response surface methodology (RSM) was used to complete the optimization procedure. The optimal levels of the chosen variables which were 30.0 g/l, glucose; 5 g/l, yeast extract and 10.0 g/l sodium acetate trihydrate with the predicted LA-EPS-20079 concentration of 794.82 µg/ml. Model validity reached 99.93% when the results were verified. Both optimized trials showed great cytotoxic effects against colon cancer line (CaCo-2) with inhibition percentages ranging from 64.6 to 81.9%. Moreover, downregulation in the expression level of BCL2 and Survivin genes was found with a fold change of 3.377 and 21.38, respectively. Finally, we concluded that the optimized LA-EPS-20079 has maintained its anticancer effect against the CaCo-2 cell line that was previously reported by our research group.


Assuntos
Neoplasias do Colo , Probióticos , Humanos , Lactobacillus acidophilus/metabolismo , Projetos de Pesquisa , Células CACO-2 , Acetato de Sódio/metabolismo , Fermentação , Neoplasias do Colo/tratamento farmacológico , Glucose/metabolismo
11.
Transplant Direct ; 9(5): e1482, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37096152

RESUMO

Combined liver-lung transplantation is an uncommon, although vital, procedure for patients with simultaneous end-stage lung and liver disease. The utility of lung-liver transplant has been questioned because of initial poor survival outcomes, particularly when compared with liver-alone transplant recipients. Methods: A single-center, retrospective review of the medical records of 19 adult lung-liver transplant recipients was conducted, comparing early recipients (2009-2014) with a recent cohort (2015-2021). Patients were also compared with the center's single lung or liver transplant recipients. Results: Recent lung-liver recipients were older (P = 0.004), had a higher body mass index (P = 0.03), and were less likely to have ascites (P = 0.02), reflecting changes in the etiologies of lung and liver disease. Liver cold ischemia time was longer in the modern cohort (P = 0.004), and patients had a longer posttransplant length of hospitalization (P = 0.048). Overall survival was not statistically different between the 2 eras studied (P = 0.61), although 1-y survival was higher in the more recent group (90.9% versus 62.5%). Overall survival after lung-liver transplant was equivalent to lung-alone recipients and was significantly lower than liver-alone recipients (5-y survival: 52%, 51%, and 75%, respectively). Lung-liver recipient mortality was primarily driven by deaths within 6 mo of transplant due to infection and sepsis. Graft failure was not significantly different (liver: P = 0.06; lung: P = 0.74). Conclusions: The severity of illness in lung-liver recipients combined with the infrequency of the procedure supports its continued use. However, particular attention should be paid to patient selection, immunosuppression, and prophylaxis against infection to ensure proper utilization of scarce donor organs.

12.
Clin Transplant ; 37(8): e14963, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36938669

RESUMO

INTRODUCTION: In an effort to maximize living donor kidney utilization, we describe the use of deceased donor vein extension grafts for right-sided living donor kidneys and report our single-center experience using this technique. METHODS: A retrospective review of kidney transplant recipients (KTR) who received a right living donor kidney with deceased donor vein extension graft. Recipient demographics, postoperative graft function, and surgical complications were reviewed. Living donor nephrectomies were performed laparoscopically. Vein grafts were obtained from recent deceased donor procurements. End-to-end anastomosis of the graft to the renal vein was performed prior to implantation. RESULTS: Thirty-eight KTR received a right kidney transplant with deceased donor extension grafts. The median recipient age and BMI were 53.0 years and 29.3 kg/m2 . Total 71% were male. Ninety-five percent of grafts displayed immediate graft function, with two recipients requiring temporary dialysis due to anaphylaxis from induction therapy. Median serum creatinine at two weeks was 1.6 mg/dL and at three months was 1.5 mg/dL. There were no graft thromboses. CONCLUSION: Utilization of deceased donor extension grafts for short right renal veins is a simple technique that expands the donor pool for living donor renal transplantation. Our experience resulted in no technical complications and excellent early graft function.


Assuntos
Transplante de Rim , Masculino , Humanos , Feminino , Transplante de Rim/métodos , Doadores Vivos , Sobrevivência de Enxerto , Rim , Veias Renais/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
13.
Am J Transplant ; 23(7): 875-890, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36958628

RESUMO

In July 2022, the Scientific Registry of Transplant Recipients (SRTR) hosted an innovative, multistakeholder consensus conference to identify information and metrics desired by stakeholders in the transplantation system, including patients, living donors, caregivers, deceased donor family members, transplant professionals, organ procurement organization professionals, payers, and regulators. Crucially, patients, caregivers, living donors, and deceased donor family members were included in all aspects of this conference, including serving on the planning committee, participating in preconference focus groups and learning sessions, speaking at the conference, moderating conference sessions and breakout groups, and shaping the conclusions. Patients constituted 24% of the meeting participants. In this report, we document the proceedings and enumerate 160 recommendations, 10 of which have been highly prioritized. SRTR will use the recommendations to develop new presentations of information and metrics requested by stakeholders to support informed decision-making.


Assuntos
Obtenção de Tecidos e Órgãos , Transplantes , Humanos , Transplantados , Benchmarking , Sistema de Registros , Doadores de Tecidos , Doadores Vivos
14.
Plast Reconstr Surg ; 151(6): 1318-1321, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36729732

RESUMO

SUMMARY: This report provides a 5-year follow-up on the first reported simultaneous scalp, calvarium, kidney, and pancreas transplant. The previously published case report represented both the first composite calvarial-scalp transplant and combination of a vascularized composite allotransplantation with double organ transplantation. Over the ensuing 5 years, the patient underwent a single episode of acute scalp rejection successfully managed with intravenous Solu-Medrol, one resection of a basal cell carcinoma on the native scalp, hardware removal, and bony contouring. In addition, the patient developed seizures secondary to delayed, postirradiation cerebral necrosis requiring craniotomy and resection. His seizures were ultimately controlled. Currently, more than 5 years after his multiorgan transplant, the patient continues to have excellent allograft function and a very satisfactory aesthetic outcome, demonstrating that in certain cases, combined vascularized composite allotransplantation with solid organ transplantation can be performed safely without compromising the solid organ transplantation.


Assuntos
Transplante de Pâncreas , Couro Cabeludo , Humanos , Couro Cabeludo/cirurgia , Seguimentos , Crânio , Rim , Rejeição de Enxerto/patologia
15.
Reprod Biol ; 23(1): 100732, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36669377

RESUMO

The negative impact of zearalenone (ZEN; potent estrogenic mycotoxin) exposure on buffalo embryo production has not yet been determined. In the current study, buffalo sperm and oocytes were exposed to ZEN at different concentrations during maturation. Sperms (with and without ZEN exposure) were incubated for 2 h and evaluated for motility, viability, acrosome integrity, normality, and ultrastructure. Matured oocytes exposed to ZEN were stained to determine their nuclear maturation. Further, their developmental ability was evaluated after in vitro fertilization. Our results showed the toxic effects of ZEN at high concentrations (2000 ng/mL) on different buffalo sperm parameters. The number of acrosome-intact sperm was reduced at 0 h after exposure to a concentration of ≥ 100 ng/mL. Furthermore, the maturation rate of buffalo oocytes (telophase I + metaphase II) was significantly decreased in ZEN-treated oocytes with a higher degeneration rate. Oocytes matured in 1000 ng/mL ZEN and subsequently exhibited considerable reduction in cleavage rate and blastocyst formation compared with control oocytes (2.6% vs. 13.1%). Moreover, the morula rate was decreased (p < 0.001) in ZEN-treated oocytes at concentrations of ≥ 10 ng/mL. Overall, the adverse effects of in vitro ZEN exposure on buffalo sperm parameters and oocyte meiotic progression with a notable reduction in cleavage, morula, and blastocyst rates were defined by these results. Altogether, buffaloes should be considered sensitive to ZEN exposure with respect to their reproductive function.


Assuntos
Búfalos , Zearalenona , Gravidez , Animais , Feminino , Masculino , Zearalenona/análise , Zearalenona/farmacologia , Sêmen , Desenvolvimento Embrionário , Oócitos , Fertilização in vitro , Espermatozoides , Técnicas de Maturação in Vitro de Oócitos/métodos , Blastocisto
16.
Transplantation ; 107(7): 1513-1523, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36706077

RESUMO

BACKGROUND: The need for liver retransplantation (reLT) has increased proportionally with greater numbers of liver transplants (LTs) performed, use of marginal donors, degree of recipient preoperative liver dysfunction, and longer survival after LT. However, outcomes following reLT have been historically regarded as poor. METHODS: To evaluate reLT in modern recipients, we retrospectively examined our single-center experience. Analysis included 1268 patients undergoing single LT and 68 patients undergoing reLT from January 2008 to December 2021. RESULTS: Pre-LT mechanical ventilation, body mass index at LT, donor-recipient ABO incompatibility, early acute rejection, and length of hospitalization were associated with increased risk of needing reLT following index transplant. Overall and graft survival outcomes in the reLT cohort were equivalent to those after single LT. Mortality after reLT was associated with Kidney Donor Profile Index, national organ sharing at reLT, and LT donor death by anoxia and blood urea nitrogen levels. Survival after reLT was independent of the interval between initial LT and reLT, intraoperative packed red blood cell use, cold ischemia time, and preoperative mechanical ventilation, all previously linked to worse outcomes. CONCLUSIONS: These data suggest that reLT is currently a safer option for patients with liver graft failure, with comparable outcomes to primary LT.


Assuntos
Hepatopatias , Transplante de Fígado , Humanos , Reoperação/efeitos adversos , Estudos Retrospectivos , Fatores de Risco , Transplante de Fígado/efeitos adversos , Sobrevivência de Enxerto
17.
Enzyme Microb Technol ; 162: 110133, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36152593

RESUMO

Recent advancements in biorefinery processes necessitate search for cost effective and thermostable cellulases. This study was designed to characterize the cellulase obtained from a thermophilic bacterium, Neobacillus sedimentimangrovi UE25. A combined pretreatment of NaOH and methyltrioctylammonium chloride was given to sugarcane bagasse (SB) for lignin removal and the pretreated SB was utilized as a carbon source for the cellulase production. The thermostable cellulase thus obtained was characterized by adopting central composite design which has not been reported earlier for this purpose. Cellulase showed its maximum activity at pH 7 and temperature 60 â„ƒ and it remained active in the presence of many salts and detergents. Endoglucanase (EG) was found to be stable for 30 min at 80 â„ƒ. The purification of EG by using DEAE column yielded specific activity and purification fold of 365.866 IU mg-1 and 4.264, respectively. The purified EG had a molecular weight of ∼45 kDa. End product tolerance of EG was also evident, as an activity of 228.57 IU mL-1 was observed in the presence of 60 mM glucose which revealed that it does not lose its activity upon accumulation of end-product when the reaction is prolonged. The purified EG exhibited Vmax and Km of 294 U mL-1 min-1 and 36 µM, respectively, in the presence of 60 mM glucose. This novel thermostable cellulase can finds its applications in industrial sector.


Assuntos
Bacillaceae , Celulase , Celulases , Saccharum , Celulase/metabolismo , Celulose/química , Saccharum/metabolismo , Estabilidade Enzimática , Temperatura , Glucose , Concentração de Íons de Hidrogênio
18.
Sci Rep ; 12(1): 22251, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-36564523

RESUMO

Phosphoric acid is the core material for the fertilizer industry; however, it is incredibly corrosive to manufacturing plants' structures, mainly steel. Corrosion is one of the most severe problems encountered during phosphate fertilizer manufacturing. Recently, plant extracts have been commonly used as corrosion inhibitors because they are cheap and environmentally friendly. Steel corrosion in a 20% aqueous phosphoric acid solution in the absence and presence of fenugreek seed (Fen) or cape gooseberry leaf (CgL) extracts was investigated using the electrochemical impedance spectroscopy technique, potentiodynamic polarization measurement, scanning electron microscope, and quantum chemical calculations. Fourier Transform Infrared, FTIR, was used to identify the functional groups in Fen and CgL extracts. The inhibition efficiency for steel in 20% aqueous phosphoric acid was roughly equal to 80% for 0.4 g/L CgL and 1.2 g/L Fen extracts. A scanning electron microscope showed that the chemical constituents of extracts block the surface roughness of steel, decreasing the corrosion rate. The activation parameters indicated the effectiveness of the extracts at a higher temperature. Measurements of the potential of zero charges showed that the steel surface is positively charged in the phosphoric acid solution. Quantum chemical computations were also employed to examine the corrosion inhibition mechanisms of the natural extracts.


Assuntos
Ribes , Aço , Aço/química , Corrosão , Fertilizantes , Extratos Vegetais/química
19.
PLoS One ; 17(12): e0278781, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36534667

RESUMO

BACKGROUND: Solid organ transplant (SOT) recipients are predicted to have worse COVID-19 outcomes due to their compromised immunity. However, this association remains uncertain because published studies have had small sample sizes and variability in chronic comorbidity adjustment. METHODS: In this retrospective cohort study conducted at a multihospital health system, we compared COVID-19 outcomes and survival up to 60 days following hospital admission in SOT recipients taking baseline immunosuppressants versus hospitalized control patients. RESULTS: The study included 4,562 patients who were hospitalized with COVID-19 (108 SOT recipients and 4,454 controls) from 03/2020 to 08/2020. Mortality at 60 days was higher for SOT recipients (17% SOT vs 10% control; unadjusted odds ratio (OR) = 1.74, 95% confidence interval (CI) 1.04-2.91, P = 0.04). We then conducted a 1:5 propensity matched cohort analysis (100 SOT recipients; 500 controls) using age, sex, race, body mass index, hypertension, diabetes, chronic kidney disease, liver disease, admission month, and area deprivation index. Within 28 days of admission, SOT recipients had fewer hospital-free days (median; 17 SOT vs 21 control; OR = 0.64, 95%CI 0.46-0.90, P = 0.01) but had similar ICU-free days (OR = 1.20, 95%CI 0.72-2.00, P = 0.49) and ventilator-free days (OR = 0.91, 95%CI 0.53-1.57, P = 0.75). There was no statistically significant difference in 28-day mortality (9% SOT vs 12% control; OR = 0.76, 95%CI 0.36-1.57, P = 0.46) or 60-day mortality (16% SOT vs 14% control; OR = 1.15, 95%CI 0.64-2.08, P = 0.64). CONCLUSIONS: Hospitalized SOT recipients appear to need additional days of hospital care but can achieve short-term mortality outcomes from COVID-19 that are similar to non-SOT recipients in a propensity matched cohort study.


Assuntos
COVID-19 , Transplante de Órgãos , Humanos , Estudos de Coortes , Estudos Retrospectivos , Hospitalização , Transplantados
20.
Nat Commun ; 13(1): 7951, 2022 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-36572684

RESUMO

Pancreatic islet transplantation efficacy for type 1 diabetes (T1D) management is limited by hypoxia-related graft attrition and need for systemic immunosuppression. To overcome these challenges, we developed the Neovascularized Implantable Cell Homing and Encapsulation (NICHE) device, which integrates direct vascularization for facile mass transfer and localized immunosuppressant delivery for islet rejection prophylaxis. Here, we investigated NICHE efficacy for allogeneic islet transplantation and long-term diabetes reversal in an immunocompetent, male rat model. We demonstrated that allogeneic islets transplanted within pre-vascularized NICHE were engrafted, revascularized, and functional, reverting diabetes in rats for over 150 days. Notably, we confirmed that localized immunosuppression prevented islet rejection without inducing toxicity or systemic immunosuppression. Moreover, for translatability efforts, we showed NICHE biocompatibility and feasibility of deployment as well as short-term allogeneic islet engraftment in an MHC-mismatched nonhuman primate model. In sum, the NICHE holds promise as a viable approach for safe and effective islet transplantation and long-term T1D management.


Assuntos
Diabetes Mellitus Tipo 1 , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Ratos , Animais , Masculino , Diabetes Mellitus Tipo 1/terapia , Terapia de Imunossupressão , Tolerância Imunológica , Imunossupressores/farmacologia , Sobrevivência de Enxerto
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...