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1.
Phys Rev Lett ; 131(16): 162501, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37925694

RESUMO

Neutrinoless double beta decay (0νßß) is a yet unobserved nuclear process that would demonstrate Lepton number violation, a clear evidence of beyond standard model physics. The process two neutrino double beta decay (2νßß) is allowed by the standard model and has been measured in numerous experiments. In this Letter, we report a measurement of 2νßß decay half-life of ^{100}Mo to the ground state of ^{100}Ru of [7.07±0.02(stat)±0.11(syst)]×10^{18} yr by the CUPID-Mo experiment. With a relative precision of ±1.6% this is the most precise measurement to date of a 2νßß decay rate in ^{100}Mo. In addition, we constrain higher-order corrections to the spectral shape, which provides complementary nuclear structure information. We report a novel measurement of the shape factor ξ_{3,1}=0.45±0.03(stat)±0.05(syst) based on a constraint on the ratio of higher-order terms from theory, which can be reliably calculated. This is compared to theoretical predictions for different nuclear models. We also extract the first value for the effective axial vector coupling constant obtained from a spectral shape study of 2νßß decay.

2.
Phys Rev Lett ; 131(22): 222501, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101385

RESUMO

We report on the results obtained with the global CUPID-0 background model, which combines the data collected in the two measurement campaigns for a total exposure of 8.82 kg×yr of ^{82}Se. We identify with improved precision the background sources within the 3 MeV energy region, where neutrinoless double ß decay of ^{82}Se and ^{100}Mo is expected, making more solid the foundations for the background budget of the next-generation CUPID experiment. Relying on the excellent data reconstruction, we measure the two-neutrino double ß-decay half-life of ^{82}Se with unprecedented accuracy: T_{1/2}^{2ν}=[8.69±0.05(stat)_{-0.06}^{+0.09}(syst)]×10^{19} yr.

3.
Phys Rev Lett ; 129(22): 222501, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36493444

RESUMO

The Cryogenic Underground Observatory for Rare Events (CUORE) at Laboratori Nazionali del Gran Sasso of INFN in Italy is an experiment searching for neutrinoless double beta (0νßß) decay. Its main goal is to investigate this decay in ^{130}Te, but its ton-scale mass and low background make CUORE sensitive to other rare processes as well. In this Letter, we present our first results on the search for 0νßß decay of ^{128}Te, the Te isotope with the second highest natural isotopic abundance. We find no evidence for this decay, and using a Bayesian analysis we set a lower limit on the ^{128}Te 0νßß decay half-life of T_{1/2}>3.6×10^{24} yr (90% CI). This represents the most stringent limit on the half-life of this isotope, improving by over a factor of 30 the previous direct search results, and exceeding those from geochemical experiments for the first time.


Assuntos
Granisetron , Meia-Vida , Teorema de Bayes
4.
Phys Rev Lett ; 129(11): 111801, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36154394

RESUMO

CUPID-0, an array of Zn^{82}Se cryogenic calorimeters, was the first medium-scale demonstrator of the scintillating bolometers' technology. The first project phase (March 2017-December 2018) allowed the most stringent limit on the neutrinoless double beta decay half-life of the isotope of interest, ^{82}Se, to be set. After a six month long detector upgrade, CUPID-0 began its second and last phase (June 2019-February 2020). In this Letter, we describe the search for neutrinoless double beta decay of ^{82}Se with a total exposure (phase I+II) of 8.82 kg yr^{-1} of isotope. We set a limit on the half-life of ^{82}Se to the ground state of ^{82}Kr of T_{1/2}^{0ν}(^{82}Se)>4.6×10^{24} yr (90% credible interval), corresponding to an effective Majorana neutrino mass m_{ßß}<(263-545) meV. We also set the most stringent lower limits on the neutrinoless decays of ^{82}Se to the 0_{1}^{+}, 2_{1}^{+}, and 2_{2}^{+} excited states of ^{82}Kr, finding 1.8×10^{23} yr, 3.0×10^{23} yr, and 3.2×10^{23} yr (90% credible interval) respectively.

5.
Phys Rev Lett ; 126(18): 181802, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34018798

RESUMO

The CUPID-Mo experiment at the Laboratoire Souterrain de Modane (France) is a demonstrator for CUPID, the next-generation ton-scale bolometric 0νßß experiment. It consists of a 4.2 kg array of 20 enriched Li_{2}^{100}MoO_{4} scintillating bolometers to search for the lepton-number-violating process of 0νßß decay in ^{100}Mo. With more than one year of operation (^{100}Mo exposure of 1.17 kg×yr for physics data), no event in the region of interest and, hence, no evidence for 0νßß is observed. We report a new limit on the half-life of 0νßß decay in ^{100}Mo of T_{1/2}>1.5×10^{24} yr at 90% C.I. The limit corresponds to an effective Majorana neutrino mass ⟨m_{ßß}⟩<(0.31-0.54) eV, dependent on the nuclear matrix element in the light Majorana neutrino exchange interpretation.

6.
Phys Rev Lett ; 123(3): 032501, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31386478

RESUMO

CUPID-0 is the first pilot experiment of CUPID, a next-generation project for the measurement of neutrinoless double beta decay (0νDBD) with scintillating bolometers. The detector, consisting of 24 enriched and 2 natural ZnSe crystals, has been taking data at Laboratori Nazionali del Gran Sasso from June 2017 to December 2018, collecting a ^{82}Se exposure of 5.29 kg×yr. In this Letter we present the phase-I results in the search for 0νDBD. We demonstrate that the technology implemented by CUPID-0 allows us to reach the lowest background for calorimetric experiments: (3.5_{-0.9}^{+1.0})×10^{-3} counts/(keV kg yr). Monitoring 3.88×10^{25} ^{82}Se nuclei×yr we reach a 90% credible interval median sensitivity of T_{1/2}^{0ν}>5.0×10^{24} yr and set the most stringent limit on the half-life of ^{82}Se 0νDBD: T_{1/2}^{0ν}>3.5×10^{24} yr (90% credible interval), corresponding to m_{ßß}<(311-638) meV depending on the nuclear matrix element calculations.

7.
Phys Rev Lett ; 123(26): 262501, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31951429

RESUMO

We report on the measurement of the two-neutrino double-ß decay of ^{82}Se performed for the first time with cryogenic calorimeters, in the framework of the CUPID-0 experiment. With an exposure of 9.95 kg yr of Zn^{82}Se, we determine the two-neutrino double-ß decay half-life of ^{82}Se with an unprecedented precision level, T_{1/2}^{2ν}=[8.60±0.03(stat) _{-0.13}^{+0.19}(syst)]×10^{19} yr. The very high signal-to-background ratio, along with the detailed reconstruction of the background sources allowed us to identify the single state dominance as the underlying mechanism of such a process, demonstrating that the higher state dominance hypothesis is disfavored at the level of 5.5σ.

8.
Osteoarthritis Cartilage ; 26(7): 978-987, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29723636

RESUMO

OBJECTIVE: The aim of the study is to assess the effects of the neuroinflammatory microenvironment of a mechanically-induced degenerating intervertebral disc (IVD) on neuroinflammatory like cells such as microglia, in order to comprehend the role of microglial cells in degenerative disc disease. METHODS: Bovine caudal IVDs were kept in culture in an ex vivo bioreactor under high frequency loading and limited nutrition or in free swelling conditions as control samples. Conditioned media (CM) were collected, analysed for cytokine and neurotrophin content and applied to microglial cells for neuroinflammatory activation assessment. RESULTS: Degenerative conditioned medium (D-CM) induced a higher production of interleukin (IL)-8, nerve growth factor (NGF), interferon (IFN)-γ, IL-17 from IVD cells than unloaded control conditioned medium (U-CM). Upon 48 h of co-incubation with microglia, D-CM stimulated microglia proliferation, activation, with increased expression of ionized calcium binding adaptor molecule 1 (IBA1) and CD68, and chemotaxis. Moreover, an increment of nitrite production was observed. Interestingly, D-CM caused an upregulation of IL-1ß, IL-6, tumour necrosis factor α (TNFα), inducible NO synthase (iNOS), IBA1, and vascular endothelial growth factor (VEGF) genes in microglia. Similar results were obtained when microglia were treated with the combination of the measured cytokines. CONCLUSIONS: Our findings show that in IVD degenerative microenvironment, IL-8, NGF, IFN-γ, IL-17 drive activation of microglia in the spinal cord and increase upregulation of neuroinflammatory markers. This, in turn, enhances the inflammatory milieu within IVD tissues and in the peridiscal space, aggravating the cascade of degenerative events. This study provides evidence for an important role of microglia in maintaining IVD neuroinflammatory microenvironment and probably inducing low back pain.


Assuntos
Proliferação de Células/efeitos dos fármacos , Quimiotaxia , Interleucina-1beta/farmacologia , Degeneração do Disco Intervertebral/metabolismo , Microglia/metabolismo , Estresse Mecânico , Animais , Bovinos , Células Cultivadas , Microambiente Celular , Meios de Cultivo Condicionados , Modelos Animais de Doenças , Humanos , Inflamação/fisiopatologia , Disco Intervertebral/metabolismo , Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/patologia , Microglia/citologia , Fator de Crescimento Neural/metabolismo , Óxido Nítrico/metabolismo , Distribuição Aleatória , Sensibilidade e Especificidade , Fator de Necrose Tumoral alfa/metabolismo
9.
Phys Rev Lett ; 120(23): 232502, 2018 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-29932707

RESUMO

We report the result of the search for neutrinoless double beta decay of ^{82}Se obtained with CUPID-0, the first large array of scintillating Zn^{82}Se cryogenic calorimeters implementing particle identification. We observe no signal in a 1.83 kg yr ^{82}Se exposure, and we set the most stringent lower limit on the 0νßß ^{82}Se half-life T_{1/2}^{0ν}>2.4×10^{24} yr (90% credible interval), which corresponds to an effective Majorana neutrino mass m_{ßß}<(376-770) meV depending on the nuclear matrix element calculations. The heat-light readout provides a powerful tool for the rejection of α particles and allows us to suppress the background in the region of interest down to (3.6_{-1.4}^{+1.9})×10^{-3} counts/(keV kg yr), an unprecedented level for this technique.

10.
Eur J Paediatr Dent ; 19(3): 247-249, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30063160

RESUMO

Determining the best choice between the different sealant materials might be complicated. The products that dentists can choose have different properties, such as caries' preventive effect, fluoride release and retention rate. According to the literature, fissure sealant materials fall into two main categories: resin-based sealants and glass ionomer sealants. Even if the "fluoride-releasing resin sealants" are better than "glass ionomer", with regards to retention of the material, the literature shows that their effectiveness in preventing fissure caries in permanent molars does not differ significantly over 24 months.


Assuntos
Cárie Dentária/prevenção & controle , Selantes de Fossas e Fissuras/química , Selantes de Fossas e Fissuras/uso terapêutico , Resinas Acrílicas/química , Resinas Acrílicas/uso terapêutico , Criança , Cimentos de Ionômeros de Vidro/química , Cimentos de Ionômeros de Vidro/uso terapêutico , Humanos
11.
Eur J Paediatr Dent ; 19(4): 333-334, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30567453

RESUMO

BACKGROUND: Bisphenol A (BPA) is a synthetic chemical resin used worldwide to produce plastic products. It is also a component of the bisphenol A diglycidylether methacrylate (Bis-GMA), which is a monomer found in dental resin-based materials (including resin-based dental sealants, RBSs). The controversy about its possible toxicity begins around the early '30s. Even if the amount of BPA released by dental sealants is well below the limit proposed by the U.S. Environmental Protection Agency and the European Food Safety Authority, we can reduce the risk of exposure, particularly for children, following precautionary measures.


Assuntos
Compostos Benzidrílicos/toxicidade , Assistência Odontológica para Crianças , Fenóis/toxicidade , Selantes de Fossas e Fissuras/toxicidade , Compostos Benzidrílicos/química , Criança , Humanos , Fenóis/química , Selantes de Fossas e Fissuras/química , Resinas Sintéticas/química , Resinas Sintéticas/toxicidade
12.
Eur J Paediatr Dent ; 19(1): 29-34, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29569450

RESUMO

AIM: The aim of this study is to evaluate the dento-alveolar effects of slow maxillary expansion using the Leaf Expander in a sample of growing patients with maxillary transverse deficiency, unilateral cross bite and mandibular shift. MATERIALS AND METHODS: The study included 10 patients, 3 male and 7 female (mean age 7.5 + 7 months), treated with Leaf Expander anchored on the upper deciduous teeth. Digital models were obtained by a lab scan of the pvs impressions at the beginning of the therapy (T1) and at the removal of the palatal expander (T2). Five parameters were measured: 1) the distance between the first upper permanent molars; 2) the distance between the upper second deciduous molars; 3) the distance between the upper canine cusps 4) the distance between the first lower permanent molars; 5) the distance of the lower canine cusps. RESULTS: In all patients complete correction of posterior crossbite was achieved on average in 4 months, with a spontaneous expansion of the upper first permanent molars. Significant increases in the dento-alveolar transversal diameters were obtained. Increases were also observed in the anterior mandibular arch diameter (+ 1 mm). CONCLUSIONS: These findings suggest that slow maxillary expansion using Leaf Expander appliance could be a reasonable alternative to conventional maxillary expansion therapy in the early mixed dentition.


Assuntos
Má Oclusão/terapia , Técnica de Expansão Palatina/instrumentação , Criança , Dentição Mista , Feminino , Humanos , Masculino , Desenvolvimento Maxilofacial , Projetos Piloto , Resultado do Tratamento
13.
Eur J Paediatr Dent ; 19(3): 199-204, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30063151

RESUMO

AIM: The aim of this study is to compare the dental and orthopaedic effects of the Leaf Expander with rapid and slow maxillary expanders. MATERIALS AND METHODS: The sample comprised 30 patients with a posterior crossbite divided into three groups: the rapid maxillary expander (RME) group (3 m, 7 f), average age 8.9 years; the slow maxillary expander (SME) group (7 m, 3 f) average age 12.2 years; the Leaf Expander (LE) group (7 m, 3 f), average age 7.9 years. Postero-anterior cephalometric studies have been obtained at the beginning of the therapy (T1) and after 9 months (T2). Nasal width, maxillary width, mandibular width, upper permanent molars width have been measured by a calibrated examiner. RESULTS: All the measurements increased significantly after the treatment (paired t-test P=0.05). Maxillary average width increased of 4.2 mm (SD 3.6 mm) in RME; + 2.8 mm (SD 2.8 mm) in RSE and +3.6 mm (SD 2.2 mm) in LE group. Upper permanent molars width increased: + 5.4 mm (SD 3.31 mm) in RME; + 5.4 mm (SD 3.3 mm) in SME and + 3.8 mm (SD 2.1 mm) in LE group. No statistical differencesbetween the groups have been found (t-student test P=.05). CONCLUSIONS: The effectiveness of the LE in transversal deficiency correction has been confirmed.


Assuntos
Cefalometria , Técnica de Expansão Palatina/instrumentação , Adolescente , Pontos de Referência Anatômicos , Criança , Dentição Mista , Feminino , Humanos , Masculino , Desenho de Aparelho Ortodôntico , Estudos Retrospectivos
14.
J Environ Manage ; 187: 560-570, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27865730

RESUMO

Conventional wastewater treatment plants (WWTPs) commonly require large capital investments as well as operation and maintenance costs. Constructed wetlands (CWs) appear as a cost-effective treatment, since they can remove a broad range of contaminants by a combination of physical, chemical and biological processes with a low cost. Therefore, CWs can be successfully applied for decentralized wastewater treatment in regions with low population density and/or with large land availability as Brazil. The present work provides a review of thirty nine studies developed on CWs implemented in Brazil to remove wastewater contaminants. Brazil current sanitation data is also considered to evaluate the potential role of CWs as decentralized wastewater treatment. Performance of CWs was evaluated according to (i) type of wetland system, (ii) different support matrix (iii) vegetation species and (iv) removal efficiency of chemical oxygen demand (COD), biological oxygen demand (BOD5), nitrogen (N), and phosphorus (P). The reviewed CWs in overall presented good efficiencies, whereas H-CWs achieved the highest removals for P, while the higher results for N were attained on VF-CW and for COD and BOD5 on HF-CW. Therefore, was concluded that CWs are an interesting solution for decentralized wastewater treatment in Brazil since it has warm temperatures, extensive radiation hours and available land. Additionally, the low percentage of population with access to the sewage network in the North and Northeast regions makes these systems especially suitable. Hence, the further implementation of CW is encouraged by the authors in regions with similar characteristics as Brazil.


Assuntos
Eliminação de Resíduos Líquidos , Águas Residuárias , Purificação da Água , Áreas Alagadas , Biodegradação Ambiental , Brasil , Humanos , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos
15.
Eur J Paediatr Dent ; 18(2): 111-115, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28598181

RESUMO

AIM: The aim of this study was to assess the effectiveness of a new protocol for deep caries treatment in deciduous teeth based on: 1) the incomplete removal of carious dentin tissue; 2) the use of new technology (ozone) for the disinfection of carious dentine; 3) the creation of a peripheral seal in healthy tissue for bonding procedures with rubber dam isolation. MATERIALS AND METHODS: From a personal database, authors selected 50 consecutive patients (28 males, 22 females; mean age 5.8 ± 1.7 years) in whom this new protocol was applied on posterior deciduous molars, for a total of 94 restorations. RESULTS: Regular follow- ups were performed at 3, 6 and 12 months by a second operator, who was asked to rate each restoration as success or failure. The success rate at 12 months was 93,62% (n. 88/94 restorations), similar to that reported in the literature for pulpotomy. CONCLUSION: The deciduous teeth considered for this study, if treated conventionally, would have probably been subjected to pulpotomy, because of the extension of the carious lesions. The proposed protocol, through the use of ozone, proved to be an excellent alternative, with the fundamental advantage of saving dental tissue and preventing the invasion of the pulp chamber.


Assuntos
Cárie Dentária/terapia , Restauração Dentária Permanente/métodos , Desinfecção/métodos , Ozônio/uso terapêutico , Dente Decíduo , Pré-Escolar , Feminino , Humanos , Masculino , Estudos Retrospectivos , Resultado do Tratamento
16.
Environ Monit Assess ; 188(7): 394, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27270482

RESUMO

This work reports the chemical monitoring of saline water and sediments at Aratu port, All Saints Bay, Brazil, when subjected to a deep dragging process (DDP) over a 2-year period (2010-2012). The aim of this work was to detect which metals had possible deleterious effects on the biota. It analyzed percentage of silt + clay and TOC and metal concentrations (As, Cd, Cu, Cr, Ni, Pb, and Zn) before, during, and after the DDP. The determination of metal concentration in sediments used the following techniques: atomic absorption spectrometer with flame, also with hydrate generation, and cold vapor spectrophotometry. The DDP disturbed the concentrations of metals in sediments and water, but 15 months after the DDP, only Cu and Zn were detectable on the bottom saline water, and 20 months after the DDP, only Zn was detectable in water. This fact indicates that these metals were longer available for absorption by the marine biota with probable deleterious effect. Indeed, studies by others during the DDP in Aratu port, indicated the decrease from 50 to 40 of the number of microalgae species identified. On the other hand, in the sediments, 20 months after the DDP, the concentrations of As, Cr, Cu, Pb, and Hg, returned to the original values, but Ni and Zn did not return to their original values. Comparison with studies by others indicated that the sediments from dredging were inappropriate for disposal at sea. This work indicated that the metals Cu, Ni, and Zn are the most deleterious elements to the marine environment.


Assuntos
Baías/química , Monitoramento Ambiental , Sedimentos Geológicos/química , Metais Pesados/análise , Poluentes Químicos da Água/análise , Brasil , Navios , Espectrofotometria Atômica
17.
Eur J Clin Microbiol Infect Dis ; 34(2): 287-301, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25169966

RESUMO

Propionibacterium acnes belongs to the normal skin microbiota, but it is also responsible for acne vulgaris and causes serious infections such as endocarditis and surgical site infections (SSI). The P. acnes population is structured into phylogenetic groups, with phylotype I being associated with acne. Herein, we explore the link between phylotypes and clinical origins in a collection of P. acnes isolated from different body sites, involved in deep infections or healthcare-associated infections (HAI), with particular emphasis on strains from cardiac SSI. Cardiac SSI have been further studied in terms of P. acnes population dynamics during the care pathway. The recA and tly genes phylotypes were compared to hemolytic behavior, susceptibility to antimicrobial agents, and clinical origins. An original approach of recA polymerase chain reaction temporal temperature gel electrophoresis (PCR-TTGE) was developed and applied for the direct identification of P. acnes phylotypes in surgical samples, in order to assess their temporal dynamics during the surgical course. Our results underlined the preferential involvement of IA-2/IB and II phylogroups in HAI and SSI. Unlike IA and II, type IA-2/IB presented a gradual increase with the depth of sampling in the peroperative phase of cardiac surgery. Phylotypes IA and IA-2/IB were both predominant in scar tissues and on postoperative skin, suggesting a specific predisposition to recolonize skin. Particular association of the phylotype IA-2/IB with SSI and its propensity to colonize wounds in cardiac surgery was observed. We assumed that the follow-up of P. acnes phylotypes during pathological processes could give new clues for P. acnes pathogenicity.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Infecções por Bactérias Gram-Positivas/microbiologia , Propionibacterium acnes/isolamento & purificação , Acne Vulgar/microbiologia , Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana , Sequência de Bases , Humanos , Dados de Sequência Molecular , Fenótipo , Filogenia , Reação em Cadeia da Polimerase , Propionibacterium acnes/genética , Propionibacterium acnes/patogenicidade , Recombinases Rec A/genética , Análise de Sequência de DNA , Pele/microbiologia
18.
Eur J Paediatr Dent ; : 1, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38623062

RESUMO

AIM: The aim of this article is to compare the performance of ZeroExpander® realised using PEEK or PA12 for the expansion of the maxilla in paediatric patients, exploring a new concept for approaching maxillary expansion with a metal-free fixed automatic appliance, based on pre-programmed set-up and anchored on deciduous teeth. MATERIALS: It is a retrospective comparative study with a sample of 40 children in early or mixed deciduous dentition and transversal maxillary deficit, 20 treated with ZeroExpander® in PEEK and 20 treated with ZeroExpander® in PA12 with a mean age of 7.3 years old. The intraoral scans at T0 and at the end of the expansion were all performed by the same operator to obtain digital models on which were performed measurements by two other different operators. A descriptive analysis was conducted using frequencies and percentages for nominal variables and means and standard deviations for continuous variables. CONCLUSION: In cases of allergy or hypersensitivity to metals or to specific chronic or acute pathological conditions, which may require periodic magnetic resonance imaging (MRI), it may not be possible to use traditional and metal fixed expansion devices. Moreover the concept of autonomous driving in paediatric orthodontics is not only possible, but it is and will be more real and very useful in the future. The "ortho-paediatric dentistry concept" will increase the range of benefits for children and their families which, in addition to care and thanks to technology, demand well-being, safety, comfort and quality of life beyond clinics.

19.
S Afr Med J ; 114(3b): e1366, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-39041444

RESUMO

BACKGROUND: South African transplant centres are faced with significant challenges in meeting the need for liver transplantation, owing to the low and ever-decreasing number of deceased-donor organs. To increase organ utility, deceased-donor split-liver transplant (DDSLT) and living-donor liver transplant (LDLT) programmes were initiated in the Wits Transplant Unit. OBJECTIVE: To evaluate outcomes of the LDLT and DDSLT programmes. METHODS: A retrospective analysis of de-identified recipient and donor variables from all adult and paediatric DDSLTs and LDLTs conducted between 2013 and 2021 was performed. Comparison of categorical study variables between graft types was done with the χ2 test. Continuous variables were compared by means of the independent samples t-test. Cox proportional hazards regression was performed to examine the effect of graft type on recipient and graft survival. All comparisons were made unadjusted, and adjusted for recipient age, recipient ethnicity, donor sex, and graft-weight-to-recipient-weight ratio (GWRWR) (for the paediatric cohort); and for donor age and GWRWR (for the adult cohort). RESULTS: A total of 181 paediatric and 48 adult liver transplants have been performed since the inception of the two programmes. Chronic liver failure, specifically intra- and extrahepatic cholestatic disease, was our main indication for liver transplantation in both cohorts. There were no significant differences between the DDSLTs and LDLTs in respect of pre- or post-discharge intervention, in-hospital mortality, length of stay, and recipient or graft survival within both the paediatric and adult groups. Our overall 1- and 3-year survival estimates (95% confidence intervals) were 77% (70% - 83%) and 71% (64% - 78%) for the paediatric cohort, and 77% (62% - 87%) and 66% (50% - 78%) for the adult cohort, respectively. CONCLUSION: The results of this study demonstrate comparable outcomes between DDSLT and LDLT, indicating that both methods are effective approaches to optimise organ utilisation for liver transplantation within our setting.


Assuntos
Sobrevivência de Enxerto , Transplante de Fígado , Doadores Vivos , Humanos , Transplante de Fígado/métodos , África do Sul , Estudos Retrospectivos , Feminino , Masculino , Adulto , Criança , Adolescente , Pessoa de Meia-Idade , Adulto Jovem , Pré-Escolar , Lactente , Complicações Pós-Operatórias/epidemiologia , Doadores de Tecidos
20.
S Afr Med J ; 114(3b): e1211, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-39041451

RESUMO

BACKGROUND: Liver transplantation is the definitive management for severe acute liver failure refractory to supportive management, and end- stage chronic liver failure. Owing to a shortage of deceased liver donors, South Africa requires innovative techniques to broaden the donor pool. OBJECTIVES: This study evaluated the outcomes of the Wits Transplant Unit ABO-incompatible liver transplant (ABOi-LT) programme. METHODS: This retrospective record review compared all adult and paediatric patients receiving ABO-compatible (ABOc) and ABO-incompatible (ABOi) liver transplants from January 2014 to December 2021 with a minimum one-year follow-up. Primary outcomes were recipient and graft survival and secondary outcomes included vascular, enteric and biliary complications, relook surgery, acute cellular rejection (ACR) and lenghth of hospital stay. Cox proportional hazards regression was performed to examine the effect of ABO-compatibility group on recipient and graft survival. The relationship between the ABO-compatibility group and categorical outcomes was assessed by binomial regression. RESULTS: During the study period, 532 liver transplants were performed; 44/532 (8%) were ABOi of which 14/44 (32%) were paediatric and 30/44 (68%) adult recipients. Within the pediatric group, the proportion of transplants performed for acute liver failure was significantly higher in the ABOi group (7/14; 50%) compared with the ABOc group (33/207; 16%) (p=0.005). Comparable recipient and graft survival estimates were noted: one-, three- and five-year recipient survival in the ABOi group was 77% (95% confidence interval (CI) 44 - 92), 58% (95% CI 17 - 84) and 58% (95% CI 17 - 84) respectively. There were significantly increased relative risks of relook surgery for the ABOi group compared with the ABOc group, both overall (relative risk (RR) 1.74; 95% CI 1.10 - 2.75) and at 90 days (RR 2.28; 95% CI 1.27 - 4.11); and also, for pre-discharge bloodstream infection (BSI), (RR 1.84; 95% CI 1.11 - 3.06). In adults, there were significantly more acute indications for liver transplantation in the ABOi (10/30; 33%) compared with the ABOc group (26/281; 9%) (p=0.0007) with the most common cause being drug or toxin ingestion (16/36; 44%). For the ABOi group, recipient survival estimates (95% CI) at 1, 3 and 5 years were 71% (50 - 84), 63% (41 - 78) and 58% (37 - 75) which, as noted with complication rates, were similar between ABO groups. CONCLUSION: This study confirms ABOi-LT as a feasible option to increase the liver donor pool in this organ-depleted setting as recipient survival and complication rates were similar between ABO-compatibility groups.


Assuntos
Sistema ABO de Grupos Sanguíneos , Incompatibilidade de Grupos Sanguíneos , Sobrevivência de Enxerto , Transplante de Fígado , Humanos , Transplante de Fígado/métodos , África do Sul , Estudos Retrospectivos , Feminino , Masculino , Sistema ABO de Grupos Sanguíneos/imunologia , Adulto , Pessoa de Meia-Idade , Criança , Rejeição de Enxerto , Doença Hepática Terminal/cirurgia , Adolescente , Pré-Escolar , Obtenção de Tecidos e Órgãos/métodos , Adulto Jovem
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