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1.
EuroIntervention ; 20(17): e1098-e1106, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39219362

RESUMO

BACKGROUND: Acute ischaemic stroke (AIS) after percutaneous coronary intervention (PCI) is a rare, but debilitating, complication. However, contemporary data from real-world unselected patients are scarce. AIMS: We aimed to explore the temporal trends, outcomes and variables associated with AIS as well as in-hospital all-cause mortality in a nationwide cohort. METHODS: A retrospective analysis of healthcare records from 2006-2021 was implemented. Patients were stratified according to the occurrence of AIS in the setting of PCI. The temporal trends of AIS were analysed. A stepwise regression model was used to identify variables associated with AIS and in-hospital all-cause mortality. RESULTS: A total of 4,910,430 PCIs were included for the current analysis. AIS occurred in 4,098 cases (0.08%). An incremental increase in the incidence of AIS after PCI from 0.03% to 0.14% per year was observed from 2006-2021. The strongest associations with AIS after PCI included carotid artery disease, medical history of stroke, atrial fibrillation, presentation with an ST-segment elevation myocardial infarction (STEMI) or non-STEMI and coronary thrombectomy. For patients with AIS, a higher in-hospital all-cause mortality (18.11% vs 3.29%; p<0.001) was documented. With regard to all-cause mortality, the strongest correlations in the stroke cohort were found for cardiogenic shock, dialysis and clinical presentation with a STEMI. CONCLUSIONS: In an unselected nationwide cohort of patients hospitalised for PCI, a gradual increase in AIS incidence was noted. We identified several variables associated with AIS as well as with in-hospital mortality. Hereby, clinicians might identify the patient population at risk for a peri-interventional AIS as well as those at risk for an adverse in-hospital outcome after PCI.


Assuntos
Mortalidade Hospitalar , AVC Isquêmico , Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/tendências , Intervenção Coronária Percutânea/mortalidade , Masculino , Feminino , Idoso , AVC Isquêmico/mortalidade , AVC Isquêmico/epidemiologia , Estudos Retrospectivos , Pessoa de Meia-Idade , Mortalidade Hospitalar/tendências , Idoso de 80 Anos ou mais , Fatores de Risco , Resultado do Tratamento , Incidência , Hospitalização/estatística & dados numéricos , Infarto do Miocárdio com Supradesnível do Segmento ST/mortalidade , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Fatores de Tempo
2.
Physiol Rep ; 12(17): e16150, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39209762

RESUMO

The motor impairments experienced by people with Parkinson's disease (PD) are exacerbated during memory-guided movements. Despite this, the effect of antiparkinson medication on memory-guided movements has not been elucidated. We evaluated the effect of antiparkinson medication on motor control during a memory-guided reaching task with short and long retention delays in participants with PD and compared performance to age-matched healthy control (HC) participants. Thirty-two participants with PD completed the motor section of the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS III) and performed a memory-guided reaching task with two retention delays (0.5 s and 5 s) while on and off medication. Thirteen HC participants completed the MDS-UPDRS III and performed the memory-guided reaching task. In the task, medication increased movement velocity, decreased movement time, and decreased reaction time toward what was seen in the HC. However, movement amplitude and reaching error were unaffected by medication. Shorter retention delays increased movement velocity and amplitude, decreased movement time, and decreased error, but increased reaction times in the participants with PD and HC. Together, these results imply that antiparkinson medication is more effective at altering the neurophysiological mechanisms controlling movement velocity and reaction time compared with other aspects of movement control.


Assuntos
Antiparkinsonianos , Doença de Parkinson , Desempenho Psicomotor , Tempo de Reação , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/fisiopatologia , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Antiparkinsonianos/uso terapêutico , Antiparkinsonianos/administração & dosagem , Tempo de Reação/efeitos dos fármacos , Desempenho Psicomotor/efeitos dos fármacos , Movimento , Memória/efeitos dos fármacos
3.
Nat Methods ; 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39174710

RESUMO

Over the last decade, biology has begun utilizing 'big data' approaches, resulting in large, comprehensive atlases in modalities ranging from transcriptomics to neural connectomics. However, these approaches must be complemented and integrated with 'small data' approaches to efficiently utilize data from individual labs. Integration of smaller datasets with major reference atlases is critical to provide context to individual experiments, and approaches toward integration of large and small data have been a major focus in many fields in recent years. Here we discuss progress in integration of small data with consortium-sized atlases across multiple modalities, and its potential applications. We then examine promising future directions for utilizing the power of small data to maximize the information garnered from small-scale experiments. We envision that, in the near future, international consortia comprising many laboratories will work together to collaboratively build reference atlases and foundation models using small data methods.

4.
J R Stat Soc Ser C Appl Stat ; 73(4): 1082-1109, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39145308

RESUMO

Motivated by the questions of risk assessment in climatology (temperature change in North America) and medicine (impact of statin usage and coronavirus disease 2019 on hospitalized patients), we address the problem of estimating the set in the domain of a function whose image equals a predefined subset of the real line. Existing methods require strict assumptions. We generalize the estimation of such sets to dense and nondense domains with protection against inflated Type I error in exploratory data analysis. This is achieved by proving that confidence sets of multiple upper, lower, or interval sets can be simultaneously constructed with the desired confidence nonasymptotically through inverting simultaneous confidence intervals. Nonparametric bootstrap algorithm and code are provided.

5.
Artigo em Inglês | MEDLINE | ID: mdl-39185869

RESUMO

BACKGROUND AND OBJECTIVES: One of the major challenges in training neurosurgical and orthopedic residents the technique for minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is the lack of visualization of surgical landmarks (pedicle, pars, lamina). This is due to the limited access to the bony spine through a tubular retractor, in addition to a smaller working corridor or patient-specific factors such as bony overgrowth, disk space collapse, and listhesis. These factors increase the possibility for surgical error and prolonged surgery time. With augmented reality (AR), relevant surgical anatomy can be projected directly into the user's field of view through the microscope. The purpose of this study was to assess the utility, accuracy, efficiency, and precision of AR-guided MIS-TLIF and to determine its impact in spine surgery training. METHODS: At 2 centers, 12 neurosurgical residents performed a one-level MIS-TLIF on a high-fidelity lumbar spine simulation model with and without AR projection into the microscope. For the MIS-TLIF procedures with AR, surgical landmarks were highlighted in different colors on preoperative image data. These landmarks were visualized in the spinal navigation application on the navigation monitor and in the microscope to confirm the relevant anatomy. Postprocedural surveys (National Aeronautics and Space Administration Task Load Index) were given to the residents. RESULTS: Twelve residents were included in this trial. AR-guided procedures had a consistent impact on resident anatomical orientation and workload experience. Procedures performed without AR had a significantly higher mental demand (P = .003) than with AR. Residents reported to a significantly higher rate that it was harder work for them to accomplish their level of performance without AR (P = .019). CONCLUSION: AR can bring a meaningful value in MIS teaching and training to confirm relevant anatomy in situations where the surgeon will have less direct visual access. AR used in surgical simulation can also speed the learning curve.

6.
Nat Commun ; 15(1): 6611, 2024 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-39098889

RESUMO

Identifying cellular identities is a key use case in single-cell transcriptomics. While machine learning has been leveraged to automate cell annotation predictions for some time, there has been little progress in scaling neural networks to large data sets and in constructing models that generalize well across diverse tissues. Here, we propose scTab, an automated cell type prediction model specific to tabular data, and train it using a novel data augmentation scheme across a large corpus of single-cell RNA-seq observations (22.2 million cells). In this context, we show that cross-tissue annotation requires nonlinear models and that the performance of scTab scales both in terms of training dataset size and model size. Additionally, we show that the proposed data augmentation schema improves model generalization. In summary, we introduce a de novo cell type prediction model for single-cell RNA-seq data that can be trained across a large-scale collection of curated datasets and demonstrate the benefits of using deep learning methods in this paradigm.


Assuntos
Análise de Célula Única , Análise de Célula Única/métodos , Humanos , RNA-Seq/métodos , Aprendizado de Máquina , Redes Neurais de Computação , Transcriptoma , Análise de Sequência de RNA/métodos , Animais , Biologia Computacional/métodos , Aprendizado Profundo , Perfilação da Expressão Gênica/métodos , Algoritmos
7.
Nat Methods ; 21(8): 1430-1443, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39122952

RESUMO

Recent efforts to construct reference maps of cellular phenotypes have expanded the volume and diversity of single-cell omics data, providing an unprecedented resource for studying cell properties. Despite the availability of rich datasets and their continued growth, current single-cell models are unable to fully capitalize on the information they contain. Transformers have become the architecture of choice for foundation models in other domains owing to their ability to generalize to heterogeneous, large-scale datasets. Thus, the question arises of whether transformers could set off a similar shift in the field of single-cell modeling. Here we first describe the transformer architecture and its single-cell adaptations and then present a comprehensive review of the existing applications of transformers in single-cell analysis and critically discuss their future potential for single-cell biology. By studying limitations and technical challenges, we aim to provide a structured outlook for future research directions at the intersection of machine learning and single-cell biology.


Assuntos
Análise de Célula Única , Análise de Célula Única/métodos , Humanos , Aprendizado de Máquina , Animais , Biologia Computacional/métodos , Genômica/métodos
8.
Elife ; 132024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39042440

RESUMO

Genetically encoded calcium indicators (GECIs) such as GCaMP are invaluable tools in neuroscience to monitor neuronal activity using optical imaging. The viral transduction of GECIs is commonly used to target expression to specific brain regions, can be conveniently used with any mouse strain of interest without the need for prior crossing with a GECI mouse line, and avoids potential hazards due to the chronic expression of GECIs during development. A key requirement for monitoring neuronal activity with an indicator is that the indicator itself minimally affects activity. Here, using common adeno-associated viral (AAV) transduction procedures, we describe spatially confined aberrant Ca2+ microwaves slowly travelling through the hippocampus following expression of GCaMP6, GCaMP7, or R-CaMP1.07 driven by the synapsin promoter with AAV-dependent gene transfer in a titre-dependent fashion. Ca2+ microwaves developed in hippocampal CA1 and CA3, but not dentate gyrus nor neocortex, were typically first observed at 4 wk after viral transduction, and persisted up to at least 8 wk. The phenomenon was robust and observed across laboratories with various experimenters and setups. Our results indicate that aberrant hippocampal Ca2+ microwaves depend on the promoter and viral titre of the GECI, density of expression, as well as the targeted brain region. We used an alternative viral transduction method of GCaMP which avoids this artefact. The results show that commonly used Ca2+-indicator AAV transduction procedures can produce artefactual Ca2+ responses. Our aim is to raise awareness in the field of these artefactual transduction-induced Ca2+ microwaves, and we provide a potential solution.


Assuntos
Cálcio , Dependovirus , Hipocampo , Sinapsinas , Animais , Dependovirus/genética , Sinapsinas/metabolismo , Sinapsinas/genética , Cálcio/metabolismo , Hipocampo/metabolismo , Camundongos , Vetores Genéticos , Transdução Genética , Regiões Promotoras Genéticas , Camundongos Endogâmicos C57BL , Masculino
9.
Eur J Med Chem ; 276: 116676, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39067437

RESUMO

Our previously reported HDAC6 inhibitor (HDAC6i) Marbostat-100 (4) has provided many arguments for further clinical evaluation. By the substitution of the acidic hydrogen of 4 for different carbon residues, we were able to generate an all-carbon stereocenter, which significantly improves the hydrolytic stability of the inhibitor. Further asymmetric synthesis has shown that the (S)-configured inhibitors preferentially bind to HDAC6. This led to the highly selective and potent methyl-substituted derivative S-29b, which elicited a long-lasting tubulin hyperacetylation in MV4-11 cells. Finally, a crystal structure of the HDAC6/S-29b complex provided mechanistic explanation for the high potency and stereoselectivity of synthesized compound series.


Assuntos
Carbolinas , Desacetilase 6 de Histona , Inibidores de Histona Desacetilases , Humanos , Carbolinas/química , Carbolinas/farmacologia , Carbolinas/síntese química , Linhagem Celular Tumoral , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Desacetilase 6 de Histona/antagonistas & inibidores , Desacetilase 6 de Histona/metabolismo , Inibidores de Histona Desacetilases/química , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/síntese química , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade , Morfolinas/síntese química , Morfolinas/química , Morfolinas/farmacologia
10.
S Afr Med J ; 114(3b): e1367, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-39041443

RESUMO

BACKGROUND: In the paediatric liver transplant programme in Johannesburg, South Africa (SA), tacrolimus is the calcineurin inhibitor of choice, comprising an essential component of the immunosuppression regimen. It is characterised by a narrow therapeutic index and wide interpatient variability, necessitating therapeutic drug monitoring of whole-blood concentrations. Pharmacogenetic research, although not representative of SA population groups, suggests that single-nucleotide polymorphisms within the cytochrome P450 3A5 (CYP3A5) gene contribute to the variability in tacrolimus dosing requirements. The rs776746 polymorphism, CYP3A5*3, results in a splice defect and a non-functional enzyme. Clinically, to reach the same tacrolimus concentration-to-dose ratio (CDR), expressors (CYP3A5*1/*1 and *1/*3) require a higher tacrolimus dose than non-expressors (*3/*3). OBJECTIVES: To compare the pharmacokinetics of tacrolimus in paediatric liver transplant recipients with their donors' CYP3A5 genotypes, considering both donor and recipient characteristics. METHODS: Blood samples from 46 living liver donors were collected, their genomic DNA was extracted, and their CYP3A5 genotype was established (polymerase chain reaction and restriction fragment length polymorphism analysis, validated by Sanger sequencing). The relationship of donor and recipient characteristics with the mean tacrolimus CDR was analysed using a general linear model. Non- confounding significant variables were included in a multiple regression model. RESULTS: The study showed that all expressor donors genotyped as CYP3A5*1/*1 were of black African self-reported race and ethnicity. During the first 15 days post-transplant, we found that children who received grafts from donor CYP3A5 expressors (CYP3A5*1/*1 and *1/*3) had significantly lower mean tacrolimus CDRs compared with those who received grafts from donor CYP3A5 non-expressors (*3/*3); the recipients of CYP3A5 expressor grafts therefore require higher doses of oral tacrolimus to achieve the same therapeutic target range. In addition, graft-to-recipient weight ratio and the CYP3A5 donor genotypes were independent factors that significantly (p<0.05) affected mean tacrolimus CDRs in recipients. CONCLUSION: In this study, we showed that all CYP3A5*1 homozygote donors were of black African self-reported race and ethnicity, and tacrolimus CDRs in paediatric living-donor liver transplant recipients were significantly affected by donor graft size and donor CYP3A5 genotypes. Information from this study may inform the development of an Afrocentric tacrolimus precision-medicine algorithm to optimise recipient safety and graft outcomes.


Assuntos
Citocromo P-450 CYP3A , Genótipo , Imunossupressores , Transplante de Fígado , Polimorfismo de Nucleotídeo Único , Tacrolimo , Humanos , Tacrolimo/farmacocinética , Tacrolimo/administração & dosagem , Tacrolimo/uso terapêutico , Citocromo P-450 CYP3A/genética , África do Sul , Criança , Imunossupressores/farmacocinética , Imunossupressores/administração & dosagem , Imunossupressores/uso terapêutico , Masculino , Feminino , Pré-Escolar , Adolescente , Doadores Vivos , Lactente
11.
Genome Biol ; 25(1): 181, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38978088

RESUMO

Single-cell multiomic analysis of the epigenome, transcriptome, and proteome allows for comprehensive characterization of the molecular circuitry that underpins cell identity and state. However, the holistic interpretation of such datasets presents a challenge given a paucity of approaches for systematic, joint evaluation of different modalities. Here, we present Panpipes, a set of computational workflows designed to automate multimodal single-cell and spatial transcriptomic analyses by incorporating widely-used Python-based tools to perform quality control, preprocessing, integration, clustering, and reference mapping at scale. Panpipes allows reliable and customizable analysis and evaluation of individual and integrated modalities, thereby empowering decision-making before downstream investigations.


Assuntos
Análise de Célula Única , Software , Transcriptoma , Análise de Célula Única/métodos , Perfilação da Expressão Gênica/métodos , Humanos , Fluxo de Trabalho
12.
S Afr Med J ; 114(3b): e1365, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-39041445

RESUMO

In 2022, the Wits Transplant Unit performed 57 liver transplants: 33/57 adult (58%) and 24/57 paediatric (42%) recipients. At the beginning of 2022, 28 candidates were on the adult waitlist. Forty-six candidates were added to the waitlist during the year. Sixty-five percent of waitlisted candidate were transplanted. Adult candidates remained on the waitlist for longer than previous years, with 52% of them waitlisted for less than one year before undergoing liver transplantation. There was a decrease in adult pretransplant mortality to 9% in 2021 from 25% in 2020. The most common aetiology in waitlist candidates was alcoholic steatohepatitis (ASH)/non-alcoholic steatohepatitis (NASH) (36%) and in recipients cholestatic (primary sclerosing cholangitis (PSC) and primary biliary sclerosis (PBC)) (40%). Most adult recipients received a deceased donor graft (79%). Unadjusted recipient one- and three-year survivals were 75% (95% confidence interval (CI) 65 - 83) and 74% (95% CI 65 - 81), respectively. In the paediatric population, the most common aetiologies for both pretransplant candidates and transplant recipients remained cholestatic disease and acute liver failure. There was a decrease in paediatric pretransplant mortality from 27% in 2017 to 6% in 2021. Unlike the adult cohort, most paediatric recipients received a living donor graft (79%). Unadjusted one-year and three-year survival rates were 85% (95% CI 75 - 92) and 68% (95% CI 56 - 77), respectively.


Assuntos
Transplante de Fígado , Listas de Espera , Humanos , Listas de Espera/mortalidade , Adulto , Criança , África do Sul/epidemiologia , Masculino , Feminino , Adolescente , Pessoa de Meia-Idade , Adulto Jovem , Pré-Escolar , Taxa de Sobrevida , Lactente
13.
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
14.
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
15.
S Afr Med J ; 114(3b): e1190, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-39041452

RESUMO

BACKGROUND: The Wits Transplant Unit performed its first paediatric liver transplant in 2005. Initial experiences from the unit were published in 2012 and 2014. Since then, significant progress has been made in capacity-building the unit, improving outcomes and enhancing service delivery. This paper presents a broad overview and update of the unit's 17-year experience.   Methods: We conducted a retrospective review of all paediatric liver transplants performed in Johannesburg from 1 January 2005 to 31 December 2021 with a minimum one-year follow-up. Data were accessed from the Wits Donald Gordon Medical Centre Paediatric Liver Transplant Research Database (University of the Witwatersrand Human Research Ethics approval: M190749). The following data were collected: donor and recipient sociodemographic and clinical characteristics, details of transplant procedures, donor grafts and recipient outcomes (post-operative complications, graft and recipient survival).   Results: A total of 270 transplants were performed during the review period. Two thirds of recipients (n=180, 67%) were younger than 5 years at time of transplant and half (n=135, 50%) received a living donor graft. The most common indication for liver transplant was biliary atresia, followed by acute liver failure. Unadjusted recipient survival was 80% (95% CI: 75-85%) at one year, and 68% (95% CI: 59-75%) at five years. Waiting list mortality decreased from 27.3% in 2017 to 5.9% in 2021. One hundred and fifty-four (57.0%) recipients experienced at least one type of intervention requiring surgical complication - the most common being biliary in nature (n = 91; 33.7%).   Conclusion: Over last seventeen years, a sustainable paediatric liver transplantation service has been established in Johannesburg. Living donor, split and ABO incompatible liver transplants have been incorporated in response to the severe organ shortage in South Africa. However, our outcomes can be improved. Additionally, a national transplant initiative to coordinate timeous referrals and expand access to liver transplantation for children with severe acute and chronic liver failure is advised.


Assuntos
Transplante de Fígado , Humanos , África do Sul , Estudos Retrospectivos , Criança , Pré-Escolar , Masculino , Feminino , Adolescente , Lactente , Sobrevivência de Enxerto , Doadores Vivos , Complicações Pós-Operatórias/epidemiologia , Atresia Biliar/cirurgia
16.
Eye (Lond) ; 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39068248

RESUMO

OBJECTIVES: To determine real-life quantitative changes in OCT biomarkers in a large set of treatment naive patients in a real-life setting undergoing anti-VEGF therapy. For this purpose, we devised a novel deep learning based semantic segmentation algorithm providing the first benchmark results for automatic segmentation of 11 OCT features including biomarkers for neovascular age-related macular degeneration (nAMD). METHODS: Training of a Deep U-net based semantic segmentation ensemble algorithm for state-of-the-art semantic segmentation performance which was used to analyze OCT features prior to, after 3 and 12 months of anti-VEGF therapy. RESULTS: High F1 scores of almost 1.0 for neurosensory retina and subretinal fluid on a separate hold-out test set with unseen patients. The algorithm performed worse for subretinal hyperreflective material and fibrovascular PED, on par with drusenoid PED, and better in segmenting fibrosis. In the evaluation of treatment naive OCT scans, significant changes occurred for intraretinal fluid (mean: 0.03 µm3 to 0.01 µm3, p < 0.001), subretinal fluid (0.08 µm3 to 0.01 µm3, p < 0.001), subretinal hyperreflective material (0.02 µm3 to 0.01 µm3, p < 0.001), fibrovascular PED (0.12 µm3 to 0.09 µm3, p = 0.02) and central retinal thickness C0 (225.78 µm3 to 169.40 µm3). The amounts of intraretinal fluid, fibrovascular PED, and ERM were predictive of poor outcome. CONCLUSIONS: The segmentation algorithm allows efficient volumetric analysis of OCT scans. Anti-VEGF provokes most potent changes in the first 3 months while a gradual loss of RPE hints at a progressing decline of visual acuity. Additional research is required to understand how these accurate OCT predictions can be leveraged for a personalized therapy regimen.

17.
J Am Coll Cardiol ; 84(2): 165-177, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38960510

RESUMO

BACKGROUND: Conventional low-density lipoprotein cholesterol (LDL-C) quantification includes cholesterol attributable to lipoprotein(a) (Lp(a)-C) due to their overlapping densities. OBJECTIVES: The purposes of this study were to compare the association between LDL-C and LDL-C corrected for Lp(a)-C (LDLLp(a)corr) with incident coronary heart disease (CHD) in the general population and to investigate whether concomitant Lp(a) values influence the association of LDL-C or apolipoprotein B (apoB) with coronary events. METHODS: Among 68,748 CHD-free subjects at baseline LDLLp(a)corr was calculated as "LDL-C-Lp(a)-C," where Lp(a)-C was 30% or 17.3% of total Lp(a) mass. Fine and Gray competing risk-adjusted models were applied for the association between the outcome incident CHD and: 1) LDL-C and LDLLp(a)corr in the total sample; and 2) LDL-C and apoB after stratification by Lp(a) mass (≥/<90th percentile). RESULTS: Similar risk estimates for incident CHD were found for LDL-C and LDL-CLp(a)corr30 or LDL-CLp(a)corr17.3 (subdistribution HR with 95% CI) were 2.73 (95% CI: 2.34-3.20) vs 2.51 (95% CI: 2.15-2.93) vs 2.64 (95% CI: 2.26-3.10), respectively (top vs bottom fifth; fully adjusted models). Categorization by Lp(a) mass resulted in higher subdistribution HRs for uncorrected LDL-C and incident CHD at Lp(a) ≥90th percentile (4.38 [95% CI: 2.08-9.22]) vs 2.60 [95% CI: 2.21-3.07]) at Lp(a) <90th percentile (top vs bottom fifth; Pinteraction0.39). In contrast, apoB risk estimates were lower in subjects with higher Lp(a) mass (2.43 [95% CI: 1.34-4.40]) than in Lp(a) <90th percentile (3.34 [95% CI: 2.78-4.01]) (Pinteraction0.49). CONCLUSIONS: Correction of LDL-C for its Lp(a)-C content provided no meaningful information on CHD-risk estimation at the population level. Simple categorization of Lp(a) mass (≥/<90th percentile) influenced the association between LDL-C or apoB with future CHD mostly at higher Lp(a) levels.


Assuntos
Apolipoproteínas B , LDL-Colesterol , Doença das Coronárias , Lipoproteína(a) , Humanos , Lipoproteína(a)/sangue , LDL-Colesterol/sangue , Masculino , Feminino , Doença das Coronárias/sangue , Doença das Coronárias/epidemiologia , Pessoa de Meia-Idade , Apolipoproteínas B/sangue , Idoso , Adulto , Fatores de Risco , Medição de Risco/métodos , Incidência
18.
Artigo em Alemão | MEDLINE | ID: mdl-38904775

RESUMO

The prevalence of cardiovascular diseases increases with age. Common symptoms such as dyspnea, chest pain, dizziness, or syncope can impact driving fitness. Due to a growing number of private drivers aged 65 and older and an increasing prevalence of cardiovascular diseases, questions regarding driving fitness restrictions for cardiological patients are gaining prominence in clinical settings. This article aims to summarize current recommendations for driving fitness in the context of cardiovascular diseases. The basis for the guidelines includes the Driving License Ordinance, the expert assessment guidelines of the Federal Highway Research Institute, and the guidelines of the German Society of Cardiology on driving fitness. Original literature on this topic is limited.Emphasizing an individualized assessment, clear guidelines for driving fitness in cardiac diseases or their symptoms and treatments are formulated. Regardless of the cardiac condition, the symptoms and likelihood of sudden loss of consciousness play a leading role in driving fitness assessment. Resulting impairments can range from a few weeks to a complete revocation of driving fitness. Regular examinations and differentiated assessments by medical professionals are prerequisites for maintaining driving fitness.The driving fitness of older private drivers is a significant and practical topic in cardiology. Current guidelines support the treating physicians in providing appropriate recommendations.


Assuntos
Condução de Veículo , Doenças Cardiovasculares , Limitação da Mobilidade , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Exame para Habilitação de Motoristas/legislação & jurisprudência , Condução de Veículo/legislação & jurisprudência , Doenças Cardiovasculares/terapia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Avaliação Geriátrica/métodos , Alemanha , Aptidão Física
19.
Viruses ; 16(6)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38932176

RESUMO

This article develops a multi-perspective view on motivations and methods for tobamovirus purification through the ages and presents a novel, efficient, easy-to-use approach that can be well-adapted to different species of native and functionalized virions. We survey the various driving forces prompting researchers to enrich tobamoviruses, from the search for the causative agents of mosaic diseases in plants to their increasing recognition as versatile nanocarriers in biomedical and engineering applications. The best practices and rarely applied options for the serial processing steps required for successful isolation of tobamoviruses are then reviewed. Adaptations for distinct particle species, pitfalls, and 'forgotten' or underrepresented technologies are considered as well. The article is topped off with our own development of a method for virion preparation, rooted in historical protocols. It combines selective re-solubilization of polyethylene glycol (PEG) virion raw precipitates with density step gradient centrifugation in biocompatible iodixanol formulations, yielding ready-to-use particle suspensions. This newly established protocol and some considerations for perhaps worthwhile further developments could serve as putative stepping stones towards preparation procedures appropriate for routine practical uses of these multivalent soft-matter nanorods.


Assuntos
Tobamovirus , Vírion , Vírion/isolamento & purificação , Tobamovirus/genética , Tobamovirus/isolamento & purificação , Doenças das Plantas/virologia , Virologia/métodos , Centrifugação com Gradiente de Concentração/métodos
20.
Lipids Health Dis ; 23(1): 197, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926753

RESUMO

BACKGROUND: Lipids, including phospholipids and bile acids, exert various signaling effects and are thought to contribute to the development of coronary artery disease (CAD). Here, we aimed to compare lipidomic and bile acid profiles in the blood of patients with and without CAD stratified by sex. METHODS: From 2015 to 2022, 3,012 patients who underwent coronary angiography were recruited in the INTERCATH cohort. From the overall cohort, subgroups were defined using patient characteristics such as CAD vs. no CAD, 1st vs. 3rd tertile of LDL-c, and female vs. male sex. Hereafter, a matching algorithm based on age, BMI, hypertension status, diabetes mellitus status, smoking status, the Mediterranean diet score, and the intake of statins, triglycerides, HDL-c and hs-CRP in a 1:1 ratio was implemented. Lipidomic analyses of stored blood samples using the Lipidyzer platform (SCIEX) and bile acid analysis using liquid chromatography with tandem mass spectrometry (LC‒MS/MS) were carried out. RESULTS: A total of 177 matched individuals were analyzed; the median ages were 73.5 years (25th and 75th percentile: 64.1, 78.2) and 71.9 years (65.7, 77.2) for females and males with CAD, respectively, and 67.6 years (58.3, 75.3) and 69.2 years (59.8, 76.8) for females and males without CAD, respectively. Further baseline characteristics, including cardiovascular risk factors, were balanced between the groups. Women with CAD had decreased levels of phosphatidylcholine and diacylglycerol, while no differences in bile acid profiles were detected in comparison to those of female patients without CAD. In contrast, in male patients with CAD, decreased concentrations of the secondary bile acid species glycolithocholic and lithocholic acid, as well as altered levels of specific lipids, were detected compared to those in males without CAD. Notably, male patients with low LDL-c and CAD had significantly greater concentrations of various phospholipid species, particularly plasmalogens, compared to those in high LDL-c subgroup. CONCLUSIONS: We present hypothesis-generating data on sex-specific lipidomic patterns and bile acid profiles in CAD patients. The data suggest that altered lipid and bile acid composition might contribute to CAD development and/or progression, helping to understand the different disease trajectories of CAD in women and men. REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT04936438 , Unique identifier: NCT04936438.


Assuntos
Ácidos e Sais Biliares , Doença da Artéria Coronariana , Lipidômica , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ácidos e Sais Biliares/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Doença da Artéria Coronariana/sangue , Caracteres Sexuais , Fatores Sexuais , Espectrometria de Massas em Tandem , Triglicerídeos/sangue , Estudos de Coortes
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