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1.
World J Transplant ; 14(2): 91052, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38947965

RESUMO

BACKGROUND: The impact of social determinants of health in allogeneic transplant recipients in low- and middle-income countries is poorly described. This observational study analyzes the impact of place of residence, referring institution, and transplant cost coverage (out-of-pocket vs government-funded vs private insurance) on outcomes after allogeneic hematopoietic stem cell transplantation (alloHSCT) in two of Mexico's largest public and private institutions. AIM: To evaluate the impact of social determinants of health and their relationship with outcomes among allogeneic transplant recipients in Mexico. METHODS: In this retrospective cohort study, we included adolescents and adults ≥ 16 years who received a matched sibling or haploidentical transplant from 2015-2022. Participants were selected without regard to their diagnosis and were sourced from both a private clinic and a public University Hospital in Mexico. Three payment groups were compared: Out-of-pocket (OOP), private insurance, and a federal Universal healthcare program "Seguro Popular". Outcomes were compared between referred and institution-diagnosed patients, and between residents of Nuevo Leon and out-of-state. Primary outcomes included overall survival (OS), categorized by residence, referral, and payment source. Secondary outcomes encompassed early mortality, event-free-survival, graft-versus-host-relapse-free survival, and non-relapse-mortality (NRM). Statistical analyses employed appropriate tests, Kaplan-Meier method, and Cox proportional hazard regression modeling. Statistical software included SPSS and R with tidycmprsk library. RESULTS: Our primary outcome was overall survival. We included 287 patients, n = 164 who lived out of state (57.1%), and n = 129 referred from another institution (44.9%). The most frequent payment source was OOP (n = 139, 48.4%), followed by private insurance (n = 75, 26.1%) and universal coverage (n = 73, 25.4%). No differences in OS, event-free-survival, NRM, or graft-versus-host-relapse-free survival were observed for patients diagnosed locally vs in another institution, nor patients who lived in-state vs out-of-state. Patients who covered transplant costs through private insurance had the best outcomes with improved OS (median not reached) and 2-year cumulative incidence of NRM of 14% than patients who covered costs OOP (Median OS and 2-year NRM of 32%) or through a universal healthcare program active during the study period (OS and 2-year NRM of 19%) (P = 0.024 and P = 0.002, respectively). In a multivariate analysis, payment source and disease risk index were the only factors associated with overall survival. CONCLUSION: In this Latin-American multicenter study, the site of residence or referral for alloHSCT did not impact outcomes. However, access to healthcare coverage for alloHSCT was associated with improved OS and reduced NRM.

2.
Ann Intensive Care ; 14(1): 108, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980442

RESUMO

BACKGROUND: Dynamic arterial elastance (Eadyn) has been investigated for its ability to predict hypotension during the weaning of vasopressors. Our study focused on assessing Eadyn's performance in the context of critically ill adult patients admitted to the intensive care unit, regardless of diagnosis. MAIN BODY: Our study was conducted in accordance with the Preferred Reported Items for Systematic Reviews and Meta-Analysis checklist. The protocol was registered in PROSPERO (CRD42023421462) on May 26, 2023. We included prospective observational studies from the MEDLINE and Embase databases through May 2023. Five studies involving 183 patients were included in the quantitative analysis. We extracted data related to patient clinical characteristics, and information about Eadyn measurement methods, results, and norepinephrine dose. Most patients (76%) were diagnosed with septic shock, while the remaining patients required norepinephrine for other reasons. The average pressure responsiveness rate was 36.20%. The synthesized results yielded an area under the curve of 0.85, with a sensitivity of 0.87 (95% CI 0.74-0.93), specificity of 0.76 (95% CI 0.68-0.83), and diagnostic odds ratio of 19.07 (95% CI 8.47-42.92). Subgroup analyses indicated no variations in the Eadyn based on norepinephrine dosage, the Eadyn measurement device, or the Eadyn diagnostic cutoff to predict cessation of vasopressor support. CONCLUSIONS: Eadyn, evaluated through subgroup analyses, demonstrated good predictive ability for the discontinuation of vasopressor support in critically ill patients.

3.
Front Med (Lausanne) ; 11: 1380125, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38841583

RESUMO

Introduction: Invasive Pneumococcal Disease (IPD) causes significant morbidity and mortality in children under 5 y. Colombia introduced PCV10 vaccination in 2012, and the Neumocolombia network has been monitoring IPD in pediatric patients since 2008. Materials and methods: This study is a secondary analysis of a prospective cohort involving pediatric patients with IPD admitted to 17 hospitals in Colombia, from January 1st, 2017, to December 31st, 2022. We present data on serotypes (Spn), clinical characteristics, and resistance patterns. Results: We report 530 patients, 215 (40.5%) were younger than 24 months. Among these, 344 cases (64.7%) presented with pneumonia, 95 (17.9%) with primary bacteremia, 53 (10%) with meningitis, 6 (1.1%) had pneumonia and meningitis, and 32 (6%) had other IPD diagnosis. The median hospital stay was 12 days (RIQ 8-14 days), and 268 (50.6%) were admitted to the ICU, of whom 60 (11.3%) died. Serotyping was performed in 298 (56.1%). The most frequent serotypes were Spn19A (51.3%), Spn6C (7.7%), Spn3 (6.7%), Spn6A (3.6%), and Spn14 (3.6%). Of 495 (93%) isolates with known susceptibility, 46 (9.2%) were meningeal (M) and 449 (90.7%) non-meningeal (NM). Among M isolates, 41.3% showed resistance to penicillin, and 21.7% decreased susceptibility to ceftriaxone. For NM isolates, 28.2% had decreased susceptibility to penicilin, and 24.2% decreased susceptibility to ceftriaxone. Spn19A showed the highest resistant to penicillin at 47% and was linked to multiresistance. Conclusion: The prevalence of PCV10-included serotypes decreased, while serotypes 19A and 6C increased, with Spn19A being associated with multiresistance. These findings had played a crucial role in the decision made by Colombia to modify its immunization schedule by switching to PCV13 in July 2022.

4.
Front Pediatr ; 12: 1386310, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38895192

RESUMO

Background: Staphylococcus aureus infections are a significant cause of morbidity and mortality in pediatric populations worldwide. The Staphylo Research Network conducted an extensive study on pediatric patients across Colombia from 2018 to 2021. The aim of this study was to describe the epidemiological and microbiological characteristics of S. aureus in this patient group. Methods: We analyzed S. aureus isolates from WHONET-reporting centers. An "event" was a positive culture isolation in a previously negative individual after 2 weeks. We studied center characteristics, age distribution, infection type, and antibiotic susceptibilities, comparing methicillin sensitive (MSSA) and resistant S. aureus (MRSA) isolates. Results: Isolates from 20 centers across 7 Colombian cities were included. Most centers (80%) served both adults and children, with 55% offering oncology services and 85% having a PICU. We registered 8,157 S. aureus culture isolations from 5,384 events (3,345 MSSA and 1,961 MRSA) in 4,821 patients, with a median age of 5 years. Blood (26.2%) and skin/soft tissue (18.6%) were the most common infection sources. Most isolates per event remained susceptible to oxacillin (63.2%), clindamycin (94.3%), and TMP-SMX (98.3%). MRSA prevalence varied by city (<0.001), with slightly higher rates observed in exclusively pediatric hospitals. In contrast, the MRSA rate was somewhat lower in centers with Antimicrobial Stewardship Program (ASP). MRSA was predominantly isolated from osteoarticular infections and multiple foci, while MSSA was more frequently associated with recurrent infections compared to MRSA. Conclusions: This is the largest study of pediatric S. aureus infections in Colombia. We found MSSA predominance, but resistance have important regional variations. S. aureus remains susceptible to other commonly used antibiotics such as TMP-SMX and clindamycin. Ongoing monitoring of S. aureus infections is vital for understanding their behavior in children. Prospective studies within the Staphylored LATAM are underway for a more comprehensive clinical and genetic characterization.

5.
Plants (Basel) ; 13(10)2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38794457

RESUMO

Nitrogen (N) is the most important nutrient in coffee, with a direct impact on productivity, quality, and sustainability. N uptake by the roots is dominated by ammonium (NH4+) and nitrates (NO3-), along with some organic forms at a lower proportion. From the perspective of mineral fertilizer, the most common N sources are urea, ammonium (AM), ammonium nitrates (AN), and nitrates; an appropriate understanding of the right balance between N forms in coffee nutrition would contribute to more sustainable coffee production through the better N management of this important crop. The aim of this research was to evaluate the influences of different NH4-N/NO3-N ratios in coffee from a physiological and agronomical perspective, and their interaction with soil water levels. Over a period of 5 years, three trials were conducted under controlled conditions in a greenhouse with different growing media (quartz sand) and organic soil, with and without water stress, while one trial was conducted under field conditions. N forms and water levels directly influence physiological responses in coffee, including photosynthesis (Ps), chlorophyll content, dry biomass accumulation (DW), nutrient uptake, and productivity. In all of the trials, the plants group in soils with N ratios of 50% NH4-N/50% NO3-N, and 25% NH4-N/75% NO3-N showed better responses to water stress, as well as a higher Ps, a higher chlorophyll content, a higher N and cation uptake, higher DW accumulation, and higher productivity. The soil pH was significantly influenced by the N forms: the higher the NO3--N share, the lower the acidification level. The results allow us to conclude that the combination of 50% NH4-N/50% NO3-N and 25% NH4-N/75% NO3-N N forms in coffee improves the resistance capacity of the coffee to water stress, improves productivity, reduces the soil acidification level, and improves ion balance and nutrient uptake.

6.
BMC Microbiol ; 24(1): 146, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678217

RESUMO

BACKGROUND: Streptococcus pneumoniae is a global cause of community-acquired pneumonia (CAP) and invasive disease in children. The CAP-IT trial (grant No. 13/88/11; https://www.capitstudy.org.uk/ ) collected nasopharyngeal swabs from children discharged from hospitals with clinically diagnosed CAP, and found no differences in pneumococci susceptibility between higher and lower antibiotic doses and shorter and longer durations of oral amoxicillin treatment. Here, we studied in-depth the genomic epidemiology of pneumococcal (vaccine) serotypes and their antibiotic resistance profiles. METHODS: Three-hundred and ninety pneumococci cultured from 1132 nasopharyngeal swabs from 718 children were whole-genome sequenced (Illumina) and tested for susceptibility to penicillin and amoxicillin. Genome heterogeneity analysis was performed using long-read sequenced isolates (PacBio, n = 10) and publicly available sequences. RESULTS: Among 390 unique pneumococcal isolates, serotypes 15B/C, 11 A, 15 A and 23B1 were most prevalent (n = 145, 37.2%). PCV13 serotypes 3, 19A, and 19F were also identified (n = 25, 6.4%). STs associated with 19A and 19F demonstrated high genome variability, in contrast to serotype 3 (n = 13, 3.3%) that remained highly stable over a 20-year period. Non-susceptibility to penicillin (n = 61, 15.6%) and amoxicillin (n = 10, 2.6%) was low among the pneumococci analysed here and was independent of treatment dosage and duration. However, all 23B1 isolates (n = 27, 6.9%) were penicillin non-susceptible. This serotype was also identified in ST177, which is historically associated with the PCV13 serotype 19F and penicillin susceptibility, indicating a potential capsule-switch event. CONCLUSIONS: Our data suggest that amoxicillin use does not drive pneumococcal serotype prevalence among children in the UK, and prompts consideration of PCVs with additional serotype coverage that are likely to further decrease CAP in this target population. Genotype 23B1 represents the convergence of a non-vaccine genotype with penicillin non-susceptibility and might provide a persistence strategy for ST types historically associated with vaccine serotypes. This highlights the need for continued genomic surveillance.


Assuntos
Antibacterianos , Infecções Comunitárias Adquiridas , Vacinas Pneumocócicas , Sorogrupo , Streptococcus pneumoniae , Humanos , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/isolamento & purificação , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/epidemiologia , Vacinas Pneumocócicas/administração & dosagem , Vacinas Pneumocócicas/imunologia , Reino Unido/epidemiologia , Pré-Escolar , Antibacterianos/farmacologia , Criança , Irlanda/epidemiologia , Pneumonia Pneumocócica/microbiologia , Pneumonia Pneumocócica/epidemiologia , Pneumonia Pneumocócica/prevenção & controle , Lactente , Genômica , Amoxicilina/farmacologia , Masculino , Testes de Sensibilidade Microbiana , Feminino , Sequenciamento Completo do Genoma , Genoma Bacteriano , Penicilinas/farmacologia , Nasofaringe/microbiologia
7.
Biomedicines ; 12(4)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38672122

RESUMO

Proteinuria is the main predictor of kidney graft loss. However, there is little information regarding the consequences of nephrotic proteinuria (NP) and nephrotic syndrome (NS) after a kidney transplant. We aimed to describe the clinical and histopathological characteristics of kidney recipients with nephrotic-range proteinuria and compare the graft surveillance between those who developed NS and those who did not. A total of 204 patients (18.6% of kidney transplants in the study period) developed NP, and 68.1% of them had NS. Of the 110 patients who underwent a graft biopsy, 47.3% exhibited ABMR, 21.8% the recurrence of glomerulonephritis, 9.1% IFTA, and 7.3% de novo glomerulonephritis. After a median follow-up of 97.5 months, 64.1% experienced graft loss. The graft survival after the onset of NP declined from 75.8% at 12 months to 38% at 5 years, without significant differences between those with and those without NS. Patients who developed NS fewer than 3 months after the onset of NP exhibited a significantly higher risk of death-censored graft loss (HR: 1.711, 95% CI: 1.147-2.553) than those without NS or those with late NS. In conclusion, NP and NS are frequent conditions after a kidney transplant, and they imply extremely poor graft outcomes. The time from the onset of NP to the development of NS is related to graft survival.

8.
Heliyon ; 10(7): e28984, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38601560

RESUMO

Background: Molecular diagnosis of cystic fibrosis (CF) is challenging in Mexico due to the population's high genetic heterogeneity. To date, 46 pathogenic variants (PVs) have been reported, yielding a detection rate of 77%. We updated the spectrum and frequency of PVs responsible for this disease in mexican patients. Methods: We extracted genomic DNA from peripheral blood lymphocytes obtained from 297 CF patients and their parents. First, we analyzed the five most frequent PVs in the Mexican population using PCR-mediated site-directed mutagenesis. In patients with at least one identified allele, CFTR sequencing was performed using next-generation sequencing tools and multiplex ligation-dependent probe amplification. For variants not previously classified as pathogenic, we used a combination of in silico prediction, CFTR modeling, and clinical characteristics to determine a genotype-phenotype correlation. Results: We identified 95 PVs, increasing the detection rate to 87.04%. The most frequent variants were p.(PheF508del) (42.7%), followed by p.(Gly542*) (5.6%), p.(Ser945Leu) (2.9%), p.(Trp1204*) and p.(Ser549Asn) (2.5%), and CFTRdel25-26 and p.(Asn386Ilefs*3) (2.3%). The remaining variants had frequencies of <2.0%, and some were exclusive to one family. We identified 10 novel PVs localized in different exons (frequency range: 0.1-0.8%), all of which produced structural changes, deletions, or duplications in different domains of the protein, resulting in dysfunctional ion flow. The use of different in silico software and American College of Medical Genetics and Genomics (ACMG) and the Association for Molecular Pathology (AMP) criteria allowed us to assume that all of these PVs were pathogenic, causing a severe phenotype. Conclusions: In a highly heterogeneous population, combinations of different tools are needed to identify the variants responsible for CF and enable the establishment of appropriate strategies for CF diagnosis, prevention, and treatment.

10.
Res Sq ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38659939

RESUMO

Purpose: Immune checkpoint inhibitor-related pneumonitis (ICI-P) is a condition associated with high mortality, necessitating prompt recognition and treatment initiation. This study aimed to assess the impact of implementing a clinical care pathway algorithm on reducing the time to treatment for ICI-P. Methods: Patients with lung cancer and suspected ICI-P were enrolled, and a multi-modal intervention promoting algorithm use was implemented in two phases. Pre- and post-intervention analyses were conducted to evaluate the primary outcome of time from ICI-P diagnosis to treatment initiation. Results: Of the 82 patients admitted with suspected ICI-P, 73.17% were confirmed to have ICI-P, predominantly associated with non-small cell lung cancer (91.67%) and stage IV disease (95%). Pembrolizumab was the most commonly used immune checkpoint inhibitor (55%). The mean times to treatment were 2.37 days in the pre-intervention phase and, 3.07 days (p=0.46), and 1.27 days (p=0.40) in the post-intervention phases 1 and 2, respectively. Utilization of the immunotoxicity order set significantly increased from 0% to 27.27% (p = 0.04) after phase 2. While there were no significant changes in ICU admissions or inpatient mortality, outpatient pulmonology follow-ups increased statistically significantly, demonstrating enhanced continuity of care. The overall mortality for patients with ICI-P was 22%, underscoring the urgency of optimizing management strategies. Notably, all patients discharged on high-dose corticosteroids received appropriate gastrointestinal prophylaxis and prophylaxis against Pneumocystis jirovecii pneumonia infections at the end of phase 2. Conclusion: Implementing a clinical care pathway algorithm for ICI-P management standardizes care practices and enhances patient outcomes, underscoring the importance of structured approaches.

11.
Eur J Breast Health ; 20(2): 94-101, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38571688

RESUMO

Objective: High rates of negative sentinel lymph node biopsy (SLNB) in clinically node-negative (cN0) breast cancer (BC) after neoadjuvant chemotherapy (NAC) have been described. These results are associated with triple-negative (TNBC) and human epidermal growth factor receptor 2 (HER2+) subtypes achieving pathologic complete response (pCR). This study evaluates predictive variables and survival in order to assess the possible omission of SLNB after NAC. Materials and Methods: Prospective study of women with cN0 BC treated with NAC and subsequent surgery, between April 2010 and May 2021. SLNB technique included, performing axillary lymphadenectomy in the absence of detection or SLNB-positivity. Multivariable logistic regression was used for analysis of NAC-response and SLNB-results in molecular subtypes: HR-/HER2+, TNBC, HR+/HER2- and HR+/HER2+. Kaplan-Meyer and log-rank were used for survival analysis. Results: A total of 179 patients (50.5±10.1 years) were included. Of these, 39.7% achieved pCR (ypT0/Tis). HR-negative subtypes had higher pCR rates (HR-/HER2+: 59.4%; TNBC: 53.4%), with no cases of SLNB-positive. With residual disease, HR-/HER2+ and TNBC showed low rates of SLNB-positivity (6.7% and 10.3%) versus HR+ (HR+/HER2+: 20%; HR+/HER2-: 44%; p<0.001). Multivariable analysis identified independent predictors of SLNB-negativity (p<0.0001) to be: HR- [odds ratio (OR)=0.15; 95% confidence interval (CI): 0.06-0.37; p = 0.0001], HER2+ (OR=0.34; 95% CI: 0.14-0.81; p = 0.015) and high-grade Nottingham (OR=0.42; 95% CI: 0.18-0.99; p = 0.048). Disease-free survival showed worse outcomes with SLNB-positivity (p<0.0001), HR+/HER2- (p = 0.0277), larger tumor size (p = 0.002) and residual disease after NAC (p<0.0001). Conclusion: Patient selection based on NAC response, molecular subtype, and survival outcomes is a priority for establishing individualized therapeutic strategies after NAC. Molecular subtypes with higher pCR rates and lower rates of SLNB-positivity could benefit from non-invasive strategies that include omission of SLNB.

12.
J Phys Act Health ; 21(6): 578-585, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561000

RESUMO

INTRODUCTION: Lack of physical activity (PA) is associated with obesity, diabetes, hypertension, cardiovascular diseases, and cancer. Parenting practices influence PA in young children. However, there is little evidence available for adolescents. We examined whether parenting practices were associated with out-of-school PA (OSPA) in US adolescents. METHODS: This cross-sectional 2019 study analyzed data from the 2014 FLASHE study, a web-based, quota-sampled survey of parent-adolescent dyads. Inclusion required survey completion and parents to live with their teen (ages 12-17 y old). Physically limited adolescents were excluded. Dyads were stratified by teen age. Exposures included parental modeling, monitoring, facilitation, restriction, guided choice, and pressure. The outcomes of interest were OSPA Youth Activity Profile scores. Odds ratios (ORs) with 95% confidence intervals (CI) were calculated using adjusted logistic regressions. RESULTS: A total of 1109 dyads were included. Guided choice increased odds of OSPA for 15- to 17-year-olds (OR = 2.12; 95% CI, 1.17-3.84). Facilitation increased odds of OSPA for 12- to 14-year-olds (OR = 2.21; 95% CI, 1.13-4.33). Monitoring decreased odds of OSPA for 15- to 17-year-olds (OR = 0.34; 95% CI, 0.20-0.57) and 12- to 14-year-olds (OR = 0.45; 95% CI, 0.27-0.74). Friend support increased odds of OSPA in 15- to 17-year-olds (OR = 4.03; 95% CI, 2.29-7.08) and 12- to 14-year-olds (OR = 3.05; 95% CI 1.69-5.51). CONCLUSION: Future interventions should prioritize (1) shared decision making for older teens, (2) access to PA opportunities for younger adolescents, and (3) promoting peer PA and friend support for everyone.


Assuntos
Exercício Físico , Poder Familiar , Humanos , Adolescente , Masculino , Feminino , Estudos Transversais , Poder Familiar/psicologia , Criança , Estados Unidos , Inquéritos e Questionários , Relações Pais-Filho
13.
Magn Reson Imaging ; 109: 286-293, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38531463

RESUMO

INTRODUCTION: The relationship between brain lesions and stroke outcomes is crucial for advancing patient prognosis and developing effective therapies. Stroke is a leading cause of disability worldwide, and it is important to understand the neurological basis of its varied symptomatology. Lesion-symptom mapping (LSM) methods provide a means to identify brain areas that are strongly associated with specific symptoms. However, inner variations in LSM methods can yield different results. To address this, our study aimed to characterize the lesion-symptom mapping variability using three different LSM methods. Specifically, we sought to determine a lesion symptom core across LSM approaches enhancing the robustness of the analysis and removing potential spatial bias. MATERIAL & METHODS: A cohort consisting of 35 patients with either right- or left-sided middle cerebral artery strokes were enrolled and evaluated using the NIHSS at 24 h post-stroke. Anatomical T1w MRI scans were also obtained 24 h post-stroke. Lesion masks were segmented manually and three distinctive LSM methods were implemented: ROI correlation-based, univariate, and multivariate approaches. RESULTS: The results of the LSM analyses showed substantial spatial differences in the extension of each of the three lesion maps. However, upon overlaying all three lesion-symptom maps, a consistent lesion core emerged, corresponding to the territory associated with elevated NIHSS scores. This finding not only enhances the spatial accuracy of the lesion map but also underscores its clinical relevance. CONCLUSION: This study underscores the significance of exploring complementary LSM approaches to investigate the association between brain lesions and stroke outcomes. By utilizing multiple methods, we can increase the robustness of our results, effectively addressing and neutralizing potential spatial bias introduced by each individual method. Such an approach holds promise for enhancing our understanding of stroke pathophysiology and optimizing patient care strategies.


Assuntos
Mapeamento Encefálico , Acidente Vascular Cerebral , Humanos , Mapeamento Encefálico/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia , Encéfalo/patologia , Imageamento por Ressonância Magnética , Infarto da Artéria Cerebral Média
15.
Brain Imaging Behav ; 18(3): 612-621, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38332386

RESUMO

Although mild cognitive impairment is a common non-motor symptom experienced by individuals with Parkinson's Disease, the changes in intrinsic resting-state networks associated with its onset in Parkinson's remain underexamined. To address the issue, our study sought to examine resting-state network alterations and their association with total performance in the Montreal Cognitive Assessment and its cognitive domains in Parkinson's by means of functional magnetic resonance imaging of 29 Parkinson's patients with normal cognition, 25 Parkinson's patients with mild cognitive impairment, and 13 healthy controls. To contrast the Parkinson's groups with each other and the controls, the images were used to estimate the Z-score coefficient between the regions of interest from the default mode network, the salience network and the central executive network. Our first finding was that default mode and salience network connectivity decreased significantly in Parkinson's patients regardless of their cognitive status. Additionally, default mode network nodes had a negative and salience network nodes a positive correlation with the global assessment in Parkinson's with normal cognition; this inverse relationship of both networks to total score was not found in the group with cognitive impairment. Finally, a positive correlation was found between executive scores and anterior and posterior cortical network connectivity and, in the group with cognitive impairment, between language scores and salience network connectivity. Our results suggest that specific resting-state networks of Parkinson's patients with cognitive impairment differ from those of Parkinson's patients with normal cognition, supporting the evidence that cognitive impairment in Parkinson's Disease displays a differentiated neurodegenerative pattern.


Assuntos
Encéfalo , Disfunção Cognitiva , Imageamento por Ressonância Magnética , Testes de Estado Mental e Demência , Rede Nervosa , Doença de Parkinson , Descanso , Humanos , Doença de Parkinson/fisiopatologia , Doença de Parkinson/diagnóstico por imagem , Masculino , Imageamento por Ressonância Magnética/métodos , Feminino , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/diagnóstico por imagem , Descanso/fisiologia , Idoso , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Pessoa de Meia-Idade , Rede Nervosa/fisiopatologia , Rede Nervosa/diagnóstico por imagem , Função Executiva/fisiologia , Vias Neurais/fisiopatologia , Vias Neurais/diagnóstico por imagem , Rede de Modo Padrão/fisiopatologia , Rede de Modo Padrão/diagnóstico por imagem , Mapeamento Encefálico/métodos , Cognição/fisiologia
16.
J Neurol Neurosurg Psychiatry ; 95(7): 682-690, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38383154

RESUMO

BACKGROUND: Spinal cord damage is a feature of many spinocerebellar ataxias (SCAs), but well-powered in vivo studies are lacking and links with disease severity and progression remain unclear. Here we characterise cervical spinal cord morphometric abnormalities in SCA1, SCA2, SCA3 and SCA6 using a large multisite MRI dataset. METHODS: Upper spinal cord (vertebrae C1-C4) cross-sectional area (CSA) and eccentricity (flattening) were assessed using MRI data from nine sites within the ENIGMA-Ataxia consortium, including 364 people with ataxic SCA, 56 individuals with preataxic SCA and 394 nonataxic controls. Correlations and subgroup analyses within the SCA cohorts were undertaken based on disease duration and ataxia severity. RESULTS: Individuals in the ataxic stage of SCA1, SCA2 and SCA3, relative to non-ataxic controls, had significantly reduced CSA and increased eccentricity at all examined levels. CSA showed large effect sizes (d>2.0) and correlated with ataxia severity (r<-0.43) and disease duration (r<-0.21). Eccentricity correlated only with ataxia severity in SCA2 (r=0.28). No significant spinal cord differences were evident in SCA6. In preataxic individuals, CSA was significantly reduced in SCA2 (d=1.6) and SCA3 (d=1.7), and the SCA2 group also showed increased eccentricity (d=1.1) relative to nonataxic controls. Subgroup analyses confirmed that CSA and eccentricity are abnormal in early disease stages in SCA1, SCA2 and SCA3. CSA declined with disease progression in all, whereas eccentricity progressed only in SCA2. CONCLUSIONS: Spinal cord abnormalities are an early and progressive feature of SCA1, SCA2 and SCA3, but not SCA6, which can be captured using quantitative MRI.


Assuntos
Imageamento por Ressonância Magnética , Ataxias Espinocerebelares , Humanos , Ataxias Espinocerebelares/diagnóstico por imagem , Ataxias Espinocerebelares/patologia , Ataxias Espinocerebelares/genética , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Genótipo , Idoso , Medula Espinal/patologia , Medula Espinal/diagnóstico por imagem , Medula Cervical/diagnóstico por imagem , Medula Cervical/patologia , Índice de Gravidade de Doença , Estudos de Casos e Controles
17.
Am J Physiol Regul Integr Comp Physiol ; 326(5): R346-R356, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38406844

RESUMO

The aim of this study was to investigate how aging affects blood flow and structure of the brain. It was hypothesized older individuals would have lower gray matter volume (GMV), resting cerebral blood flow (CBF0), and depressed responses to isometabolic and neurometabolic stimuli. In addition, increased carotid-femoral pulse-wave velocity (PWV), carotid intima-media thickness (IMT), and decreased brachial flow-mediated dilation (FMD) would be associated with lower CBF0, cerebrovascular reactivity (CVR), and GMV. Brain scans (magnetic resonance imaging) and cardiovascular examinations were conducted in young (age = 24 ± 3 yr, range = 22-28 yr; n = 13) and old (age = 71 ± 4 yr; range = 67-82 yr, n = 14) participants, and CBF0, CVR [isometabolic % blood oxygen level-dependent (BOLD) in response to a breath hold (BH)], brain activation patterns during a working memory task (neurometabolic %BOLD response to N-back trial), GMV, PWV, IMT, and FMD were measured. CBF0 and to a lesser extent CVRBH were lower in the old group (P ≤ 0.050); however, the increase in the %BOLD response to the memory task was not blunted (P ≥ 0.2867). Age-related differential activation patterns during the working memory task were characterized by disinhibition of the default mode network in the old group (P < 0.0001). Linear regression analyses revealed PWV, and IMT were negatively correlated with CBF0, CVRBH, and GMV across age groups, but within the old group alone only the relationships between PWV-CVRBH and IMT-GMV remained significant (P ≤ 0.0183). These findings suggest the impacts of age on cerebral %BOLD responses are stimulus specific, brain aging involves alterations in cerebrovascular and possibly neurocognitive control, and arterial stiffening and wall thickening may serve a role in cerebrovascular aging.NEW & NOTEWORTHY Cerebral perfusion was lower in old versus young adults. %Blood oxygen level-dependent (BOLD) responses to an isometabolic stimulus and gray matter volume were decreased in old versus young adults and associated with arterial stiffening and wall thickening. The increased %BOLD response to a neurometabolic stimulus appeared unaffected by age; however, the old group displayed disinhibition of the default mode network during the stimulus. Thus, age-related alterations in cerebral %BOLD responses were stimulus specific and related to arterial remodeling.


Assuntos
Espessura Intima-Media Carotídea , Imageamento por Ressonância Magnética , Adulto Jovem , Humanos , Adulto , Idoso , Imageamento por Ressonância Magnética/métodos , Encéfalo/fisiologia , Envelhecimento , Circulação Cerebrovascular/fisiologia , Atrofia
19.
Plant Physiol ; 195(2): 1521-1535, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38386701

RESUMO

Fatty acid unsaturation levels affect chloroplast function and plant acclimation to environmental cues. However, the regulatory mechanism(s) controlling fatty acid unsaturation in thylakoid lipids is poorly understood. Here, we have investigated the connection between chloroplast redox homeostasis and lipid metabolism by focusing on 2-Cys peroxiredoxins (Prxs), which play a central role in balancing the redox state within the organelle. The chloroplast redox network relies on NADPH-dependent thioredoxin reductase C (NTRC), which controls the redox balance of 2-Cys Prxs to maintain the reductive activity of redox-regulated enzymes. Our results show that Arabidopsis (Arabidopsis thaliana) mutants deficient in 2-Cys Prxs contain decreased levels of trienoic fatty acids, mainly in chloroplast lipids, indicating that these enzymes contribute to thylakoid membrane lipids unsaturation. This function of 2-Cys Prxs is independent of NTRC, the main reductant of these enzymes, hence 2-Cys Prxs operates beyond the classic chloroplast regulatory redox system. Moreover, the effect of 2-Cys Prxs on lipid metabolism is primarily exerted through the prokaryotic pathway of glycerolipid biosynthesis and fatty acid desaturase 8 (FAD8). While 2-Cys Prxs and FAD8 interact in leaf membranes as components of a large protein complex, the levels of FAD8 were markedly decreased when FAD8 is overexpressed in 2-Cys Prxs-deficient mutant backgrounds. These findings reveal a function for 2-Cys Prxs, possibly acting as a scaffold protein, affecting the unsaturation degree of chloroplast membranes.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ácidos Graxos Dessaturases , Peroxirredoxinas , Tilacoides , Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos Dessaturases/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Tilacoides/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Peroxirredoxinas/metabolismo , Peroxirredoxinas/genética , Oxirredução , Cloroplastos/metabolismo , Metabolismo dos Lipídeos , Mutação/genética , Regulação da Expressão Gênica de Plantas
20.
Pathogens ; 13(2)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38392864

RESUMO

More than one million curable sexually transmitted infections occur every day. Trichomonas vaginalis is one of the main infections responsible for these epidemiological data; however, the diagnosis of this protozoan is still mainly based on microscopic and culture identification. The commercialization of immunological tests and the development of molecular techniques have improved the sensitivity of classical methods. Nevertheless, the fact that trichomoniasis is a neglected parasitic infection hinders the development of novel techniques and their implementation in routine diagnosis. This review article shows the different methods developed to identify T. vaginalis in population and the difficulties in diagnosing male and asymptomatic patients. The importance of including this parasite in routine gynecological screening, especially in pregnant women, and the importance of considering T. vaginalis as an indicator of high-risk sexual behavior are also discussed.

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