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1.
New Phytol ; 240(1): 23-40, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37501525

RESUMO

Functional traits offer a promising avenue to improve predictions of species range shifts under climate change, which will entail warmer and often drier conditions. Although the conceptual foundation linking traits with plant performance and range shifts appears solid, the predictive ability of individual traits remains generally low. In this review, we address this apparent paradox, emphasizing examples of woody plants and traits associated with drought responses at the species' rear edge. Low predictive ability reflects the fact not only that range dynamics tend to be complex and multifactorial, as well as uncertainty in the identification of relevant traits and limited data availability, but also that trait effects are scale- and context-dependent. The latter results from the complex interactions among traits (e.g. compensatory effects) and between them and the environment (e.g. exposure), which ultimately determine persistence and colonization capacity. To confront this complexity, a more balanced coverage of the main functional dimensions involved (stress tolerance, resource use, regeneration and dispersal) is needed, and modelling approaches must be developed that explicitly account for: trait coordination in a hierarchical context; trait variability in space and time and its relationship with exposure; and the effect of biotic interactions in an ecological community context.


Assuntos
Secas , Plantas , Biota , Mudança Climática , Fenótipo , Ecossistema
2.
Glob Chang Biol ; 27(10): 2113-2127, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33511746

RESUMO

Many temperate forests are changing in composition due to a combination of changes in land-use, management and climate-related disturbances. Previous research has shown that in some regions these changes frequently favour drought-tolerant tree species. However, the effects of these changes in composition on forest functioning (e.g. productivity) are unclear. We studied 25 years of change in individual tree biomass growth, ingrowth and mortality, and community composition and total plot biomass across 2663 permanent forest plots in Catalonia (NE Spain) comprising 85,220 trees of 59 species. We focused on the relationship between community-level forest productivity and drought tolerance (DT), which was estimated using hydraulic traits as well as biogeographic indicators. We found that there was a small increase (1.6%-3.2% on average) in community-mean DT (DTcwm) during the study period, concurrent with a strong increase (12.4%-19.4% on average) in DT richness (DTric; i.e. trait range). Most importantly, we found that the mean DT was negatively related to forest productivity, which was explained because drought-tolerant tree species have lower tree-level growth. In contrast, DT richness was strongly and positively related to forest productivity, probably because it allowed for a more stable production along wet and dry periods. These results suggest a negative impact of ongoing climate change on forest productivity mediated by functional composition shifts (i.e. selection of drought-tolerant species), and a positive effect of increased DT richness as a consequence of land-use legacies. Such a trend towards functional diversification, although temporary, would increase forests' capacity to resist drought and place them in a better position to face the expected change in climate.


Assuntos
Secas , Árvores , Biomassa , Mudança Climática , Espanha
3.
Clin Nephrol ; 93(1): 68-71, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31549629

RESUMO

Chronic kidney disease (CKD) is a health problem worldwide. This article's objective is to describe CKD's integration into Cuba's National Noncommunicable Diseases (NCD) Program and the main outcomes regarding the burden of CKD and associated risk factors in Cuba. Cuba offers free health services to all its citizens on the basis of a strong primary healthcare system focused on prevention. The CKD National Program is coordinated by the Institute of Nephrology and includes the National Program for Prevention of CKD, which addresses all levels of prevention. The following indicators for renal replacement treatment are from 2016. The incidence of new patients on dialysis was 109 per million population (pmp); the two main causes were hypertension (34.4%) and diabetes mellitus (29.2). In 6.3% of patients, CKD cause could not be determined because they presented at advanced stages. The prevalence of patients on dialysis was 289 pmp; 90% of dialysis patients were on hemodialysis. The main causes of death were cardiovascular diseases (30.25%), cerebrovascular diseases (11.1%), and infections (29.5%). The kidney transplant rate was 14.3 pmp. Kidney transplants performed with cadaveric donors were 86.5% of total, with living related donors 13.5%. The Isle of Youth Study (ISYS) was designed to assess predialysis chronic kidney disease patterns; its methodology has been published previously. Results: Risk factors: age > 59 years 32%, women 67.8%, overweight 34.3%, obesity 22.8%, hypertension 41.5%, diabetes 13%. Estimated CKD prevalence was 9.63%. The integration of CKD into Cuba's NCD Program has gathered knowledge of burden and trends of CKD and better risk factor control.


Assuntos
Insuficiência Renal Crônica/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Cuba/epidemiologia , Feminino , Humanos , Incidência , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Prevalência , Diálise Renal/estatística & dados numéricos , Insuficiência Renal Crônica/etiologia
4.
Clin Nephrol ; 93(1): 60-67, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31699212

RESUMO

In El Salvador, a form of chronic kidney disease (CKD) of nontraditional causes (CKDnt) affecting farmers is being reported. Its behavior has been epidemic and is responsible for tens of thousands of deaths. This article summarizes the results obtained from a series of studies conducted to identify the epidemiology and clinical behavior of this disease, proposing a case definition and an etiopathogenic hypothesis. Methods included a survey of CKD in agricultural communities studying 2,388 people ≥ 18 years and 1,755 < 18, a descriptive clinical study followed by histopathological assessment conducted in 46 possible cases of CKDnt ≥ 18 years, and a national survey to study the prevalence of CKD and associated risk factors in 4,817 participants ≥ 20 years followed by a nested case-control study. In the agricultural communities, the prevalence of CKD in adults was 18% (men: 23.9%, women: 13.9%), 26.8% in agricultural workers (non-agricultural 13.8%), CKDnt accounted for 51.9% of cases. CKD in the population < 18 years was 3.9% (mean estimated glomerular filtration rate > 160 mL/1.73m2). The national CKD prevalence was 12.6% (urban: 11.3%; rural: 14.4%; males: 17.8%, females 8.5%), and CKDnt was only 3.8%; with associations between CKD and exposure to agrochemicals. The clinical study revealed the presence of markers of kidney damage (A3 albuminuria: 80.4%; ß2-microglobulin: 78.2%), urine electrolyte anomalies (100% hypermagnesuria, 45.7% hypernatriuria, 43.5% osmotic polyuria), abnormal osteotendinous reflexes (45.7%), sensorineural hearing loss (56.5%), and damage of the tibial arteries by Doppler imaging (66.7%). Biopsies revealed a chronic tubulointerstitial nephropathy. The etiopathogenesis of CKDnt is possibly multifactorial, including environmental contamination by agrochemicals, heat stress, and dehydration.


Assuntos
Nefrite Intersticial/epidemiologia , Insuficiência Renal Crônica/epidemiologia , Adolescente , Adulto , Idoso , Agricultura , Agroquímicos/efeitos adversos , Estudos de Casos e Controles , Criança , Pré-Escolar , El Salvador/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nefrite Intersticial/etiologia , Prevalência , Insuficiência Renal Crônica/etiologia
5.
Clin Nephrol ; 83(7 Suppl 1): 24-31, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25725238

RESUMO

INTRODUCTION: In El Salvador end-stage renal disease (ESRD) was the first cause of hospital mortality overall, the first cause of hospital deaths in men, and the fifth cause of hospital mortality in women in 2013. In agricultural communities, chronic kidney disease (CKD) occurs predominantly in male agricultural workers, but it also affects women to a lesser degree, even those who are not involved in agricultural work. Internationally, most epidemiological CKD studies emphasize men and no epidemiological studies focused exclusively on women. OBJECTIVE: To describe the epidemiological characteristics of CKD in females in agricultural communities of El Salvador. METHODS: A cross-sectional epidemiological study was carried out in 2009 - 2011 based on active screening for CKD and risk factors in women aged ≥ 18 years in 3 disadvantaged populations of El Salvador: Bajo Lempa (Usulután Department), Guayapa Abajo (Ahuachapán Department), and Las Brisas (San Miguel Department). Epidemiological and clinical data were gathered through personal history, as well as urinalysis for renal damage markers, determinations of serum creatinine and glucose, and estimation of glomerular filtration rates. CKD cases were confirmed at 3 months. RESULTS: Prevalence of CKD was 13.9% in 1,412 women from 1,306 families studied. Chronic kidney disease of nontraditional causes (CKDu), not attributed to diabetes mellitus, hypertension, or proteinuric primary glomerulopathy (proteinuria > 1 g/L) was 6.6%. Prevalence of chronic renal failure was 6.8%. Prevalence of renal damage markers was 9.8% (microalbuminuria (30 - 300 mg/L) 5.7%; macroalbuminuria (> 300 mg/L) 2%; and hematuria, 2.1%. Prevalence of chronic kidney disease risk factors was: diabetes mellitus, 9.3%; hypertension, 23%; family history of CKD, 16%; family history of diabetes mellitus (DM), 18.7%; family history of hypertension (HT), 31.9%; obesity, 21%; central obesity, 30.7%; NSAID use, 84.3%; agricultural occupation, 15.2%; and contact with agrochemicals, 33.1%. CONCLUSIONS: CKD in women of Salvadoran agricultural communities is associated with disadvantaged populations, traditional (DM, HT, obesity) and non-traditional causes (environmental and occupational exposure to toxic agents and inadequate working conditions). Our results reinforce the hypotheses emerging from other studies, suggesting a multifactorial etiopathology including environmental and occupational nephrotoxic exposure.


Assuntos
Agricultura , Agroquímicos/efeitos adversos , Doenças Profissionais/epidemiologia , Exposição Ocupacional/efeitos adversos , Insuficiência Renal Crônica/epidemiologia , Adulto , Estudos Transversais , El Salvador/epidemiologia , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/induzido quimicamente , Prevalência , Insuficiência Renal Crônica/induzido quimicamente , Fatores de Risco
6.
Clin Nephrol ; 83(7 Suppl 1): 56-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25725244

RESUMO

INTRODUCTION: A chronic kidney disease of non-traditional causes (CKDu) has emerged in Central America and elsewhere, predominantly affecting male farmworkers. In El Salvador (2009), it was the second cause of death in men > 18 years old. Causality has not been determined. Most available research focused on men and there is scarce data on women. OBJECTIVES: Describe the clinical and histopathologic characteristics of CKDu in women of agricultural communities in El Salvador. METHODOLOGY: A descriptive study was carried out in 10 women with CKDu stages 2, 3a, and 3b. Researchers studied demographics, clinical examination; hematological and biochemical analyses, urine sediment, renal injury markers, and assessed renal, cardiac, and peripheral arteries, liver, pancreas, and lung anatomy and functions. Kidney biopsy was performed in all. Data was collected on the Lime Survey platform and exported to SPSS 19.0. RESULTS: Patient distribution by stages: 2 (70%), 3a (10%), 3b (20%). Occupation: agricultural 7; non-agricultural 3. RISK FACTORS: agrochemical exposure 100%; farmworkers 70%; incidental malaria 50%, NSAIDs use 40%; hypertension 40%. SYMPTOMS: nocturia 50%; dysuria 50%; arthralgia 70%; asthenia 50%; cramps 30%, profuse sweating 20%. Renal markers: albumin creatinine ratio (ACR) > 300 mg/g 90%; ß microglobulin and neutrophil gelatinase- associated lipocalin (NGAL) presence in 40%. Kidney function: hypermagnesuria 100%; hyperphosphaturia 50%, hypercalciuria 40%; hypernatriuria 30%; hyponatremia 60%, hypocalcemia 50%. Doppler: tibial artery damage 40%. Neurological: reflex abnormalities 30%; Babinski and myoclonus 20%. Neurosensorial hypoacusis 70%. Histopathology: damage restricted mostly to the tubulo-interstitium, urine was essentially bland. CONCLUSIONS: CKDu in women is a chronic tubulointerstitial nephropathy with varied extrarenal symptoms.


Assuntos
Agricultura , Agroquímicos/efeitos adversos , Doenças Profissionais/epidemiologia , Exposição Ocupacional/efeitos adversos , Insuficiência Renal Crônica/epidemiologia , Adulto , El Salvador/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/induzido quimicamente , Prevalência , Insuficiência Renal Crônica/induzido quimicamente , Fatores de Risco
7.
Nat Commun ; 15(1): 6169, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103349

RESUMO

As major terrestrial carbon sinks, forests play an important role in mitigating climate change. The relationship between the seasonal uptake of carbon and its allocation to woody biomass remains poorly understood, leaving a significant gap in our capacity to predict carbon sequestration by forests. Here, we compare the intra-annual dynamics of carbon fluxes and wood formation across the Northern hemisphere, from carbon assimilation and the formation of non-structural carbon compounds to their incorporation in woody tissues. We show temporally coupled seasonal peaks of carbon assimilation (GPP) and wood cell differentiation, while the two processes are substantially decoupled during off-peak periods. Peaks of cambial activity occur substantially earlier compared to GPP, suggesting the buffer role of non-structural carbohydrates between the processes of carbon assimilation and allocation to wood. Our findings suggest that high-resolution seasonal data of ecosystem carbon fluxes, wood formation and the associated physiological processes may reduce uncertainties in carbon source-sink relationships at different spatial scales, from stand to ecosystem levels.


Assuntos
Sequestro de Carbono , Carbono , Mudança Climática , Florestas , Estações do Ano , Traqueófitas , Madeira , Carbono/metabolismo , Madeira/metabolismo , Madeira/química , Traqueófitas/metabolismo , Biomassa , Ecossistema , Ciclo do Carbono , Árvores/metabolismo
8.
Nat Ecol Evol ; 7(10): 1620-1632, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37640766

RESUMO

Predicting drought-induced mortality (DIM) of woody plants remains a key research challenge under climate change. Here, we integrate information on the edaphoclimatic niches, phylogeny and hydraulic traits of species to model the hydraulic risk of woody plants globally. We combine these models with species distribution records to estimate the hydraulic risk faced by local woody plant species assemblages. Thus, we produce global maps of hydraulic risk and test for its relationship with observed DIM. Our results show that local assemblages modelled as having higher hydraulic risk present a higher probability of DIM. Metrics characterizing this hydraulic risk improve DIM predictions globally, relative to models accounting only for edaphoclimatic predictors or broad functional groupings. The methodology we present here allows mapping of functional trait distributions and elucidation of global macro-evolutionary and biogeographical patterns, improving our ability to predict potential global change impacts on vegetation.


Assuntos
Secas , Plantas , Mudança Climática , Fenótipo
9.
MEDICC Rev ; 24(1): 32-35, 2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35157637

RESUMO

INTRODUCTION: During the pandemic caused by the SARS-CoV-2 virus, some patients who develop severe forms of COVID-19 present thrombotic microangiopathy in the course of the disease's clinical progression. METHODS: Data came from direct patient observation and clinical records. We performed a kidney biopsy and used optical microscopy and immunofluorescence techniques. RESULTS: We present the case of a 78-year-old male patient, mestizo, overweight with a history of high blood pressure, ischemic cardiopathy and chronic obstructive pulmonary disease who was first admitted to the hospital due to respiratory symptoms and diarrhea related to COVID-19, from which he recovered. He was subsequently readmitted with symptoms of acute renal dysfunction accompanied by mild anemia and thrombocytopenia; at the same time, he resulted negative for COVID-19 via a real-time polymerase chain reaction test. A kidney biopsy revealed thrombi in glomerular capillaries, acute tubular necrosis, thickening of extraglomerular blood vessel walls, and C3 deposits in the glomerular tufts. CONCLUSIONS: We describe a case of thrombotic microangiopathy with kidney biopsy in a patient recovering from COVID-19. Acute renal dysfunction is a form of thrombotic microangiopathy that has been observed in patients recovering from COVID-19.


Assuntos
COVID-19 , Microangiopatias Trombóticas , Idoso , Cuba , Humanos , Rim , Masculino , SARS-CoV-2 , Microangiopatias Trombóticas/diagnóstico , Microangiopatias Trombóticas/etiologia
10.
Neurotox Res ; 39(2): 182-190, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33555546

RESUMO

The enzyme glutathione transferase M2-2, expressed in human astrocytes, increases its expression in the presence of aminochrome and catalyzes the conjugation of aminochrome, preventing its toxic effects. Secretion of the enzyme glutathione transferase M2-2 from U373MG cells, used as a cellular model for astrocytes, has been reported, and the enzyme is taken up by neuroblastoma SYSH-S7 cells and provide protection against aminochrome. The present study provides evidence that glutathione transferase M2-2 is released in exosomes from U373MG cells, thereby providing a means for intercellular transport of the enzyme. With particular relevance to Parkinson disease and other degenerative conditions, we propose a new mechanism by which astrocytes may protect dopaminergic neurons against the endogenous neurotoxin aminochrome.


Assuntos
Astrócitos/metabolismo , Exossomos/metabolismo , Glutationa Transferase/metabolismo , Transporte Proteico , Linhagem Celular Tumoral , Neurônios Dopaminérgicos/metabolismo , Humanos
11.
MEDICC Rev ; 22(4): 87-88, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33295327

RESUMO

At fi rst, COVID-19 was thought to be primarily a respiratory disease, progressing in some patients to serious respiratory symptoms, pneumonia, severe respiratory distress syndrome and even death. Later analysis revealed entire systems were compromised, affecting other vital organs, including the kidneys, and a correlation was observed between chronic kidney disease (CKD) and COVID-19 severity COVID-19 severity.


Assuntos
COVID-19/complicações , Nefropatias/virologia , COVID-19/epidemiologia , Cuba , Progressão da Doença , Humanos , Pandemias , Fatores de Risco , SARS-CoV-2
12.
Sci Rep ; 10(1): 9542, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32533000

RESUMO

The geographic distribution of species depends on their relationships with climate and on the biotic interactions of the species. Ecological Niche Models (ENMs) mainly consider climatic variables only and may tend to overestimate these distributions, especially for species strongly restricted by biotic interactions. We identified the preference of Laelia speciosa for different host tree species and include this information in an ENM. The effect of habitat loss and climate change on the distribution of these species was also estimated. Although L. speciosa was recorded as epiphyte at six tree species, 96% of the individuals were registered at one single species (Quercus deserticola), which indicated a strong biotic interaction. We included the distribution of this host tree as a biotic variable in the ENM of L. speciosa. The contemporary distribution of L. speciosa is 52,892 km2, which represent 4% of Mexican territory and only 0.6% of the distribution falls within protected areas. Habitat loss rate for L. speciosa during the study period was 0.6% per year. Projections for 2050 and 2070 under optimistic and pessimistic climate change scenarios indicated a severe reduction in its distribution. Climaticaly suitable areas will also shift upwards (200-400 m higher). When estimating the distribution of a species, including its interactions can improve the performance of the ENMs, allowing for more  accurate estimates of the actual distribution of the species, which in turn allows for better conservation strategies.


Assuntos
Orchidaceae/crescimento & desenvolvimento , Quercus/crescimento & desenvolvimento , Biodiversidade , Mudança Climática , Conservação dos Recursos Naturais/métodos , Ecossistema , México , Árvores/crescimento & desenvolvimento
13.
Clin Pharmacol Transl Med ; 3(1): 125-133, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31321384

RESUMO

BACKGROUND/AIMS: Aminochrome, an endogenous compound formed during dopamine oxidation can induce neurotoxicity under certain aberrant conditions and induce Parkinson-like syndrome. Glutathione transferase M2 (GSTM2) activity of astrocytes by catalysing the conjugation of aminochrome with glutathione, can offer protection against aminochrome toxicity. Some medicinal toxicity through this plants may exert protective effect against aminochrome mechanism. METHODS: In the present study, extracts from plants native to Cameroon, such as Alchornea laxiflora (leaves), Dacryodes edulis (barks), Annona muricata (seeds), Annona senegalensis (barks) were evaluated for their protection against aminochrome-induced toxicity in human glioblastoma/ astrocytoma U373MG wild type and U373MGsiGT6 cells in which GSTM2 expression was 74% silenced. The cells were pre-incubated with the plant extracts for 2 hr before addition of aminochrome (75 µM) and measurement of cell death/viability by flow cytometry after 24 hr incubation. RESULTS: The extract of A. laxiflora (1 µg/ml), D. edulis (25 µg/ml), A. muricata (25 µg/ml) and A. senegalensis (25µg/ml) significantly decreased aminochrome-induced toxicity in U373siGST6 and U373MG cells. However, only A. laxiflora and A. muricata significantly increased the mitochondria membrane potential in U373siGST6 cells following aminochrome treatment. CONCLUSION: The results indicate that extracts of some Cameroon plants can provide protection against aminochrome-induced toxicity and mitochondria dysfunction in human glioblastoma/astrocytoma cells. Although further identification of active components of these extracts is needed, potential usefulness of these compounds in Parkinson's disease may be suggested.

14.
MEDICC Rev ; 21(2-3): 29-37, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31373582

RESUMO

INTRODUCTION Chronic kidney disease has reached epidemic levels in several Central American countries since the early years of this century. In El Salvador, it is the second cause of death in men, the fifth in persons over 18 years old and the third cause of hospital deaths in the adult population. Its features, especially those of a subtype unassociated with traditional risk factors such as diabetes and high blood pressure, are only partially understood. OBJECTIVE Estimate the magnitude of chronic kidney disease in the adult population of El Salvador, considering both prevalence of the disease in its diverse forms as well as presence of potential risk factors nationally and in major subpopulations. METHODS A descriptive, cross-sectional analysis was conducted on data obtained from the Survey of Chronic Non-communicable Diseases in Adults in El Salvador, completed in 2015. The original data (interviews and measurements) were collected between October 2014 and March 2015 from 4817 adults employing a two-stage probabilistic cluster sample, with stratification of primary sampling units. Our analysis, using 20 of the 118 primary variables included in the original survey, focused on point estimation of prevalence rates and means, related to both traditional biological risk factors and nontraditional ones, such as insufficient hydration, strenuous working conditions and exposure to toxic agents. A separate analysis was performed to estimate prevalence of chronic kidney disease from nontraditional causes. Corresponding confidence intervals were calculated with proper weighting. RESULTS The general prevalence of chronic kidney disease in El Salvador was 12.8% (men 18.0%; women 8.7%). Of the chronically ill kidney patients, 13.1% were between 20 and 40 years of age. Among biological risk factors, the most frequent was high blood pressure (37.0%). Among nontraditional risk factors, high levels of sugary drink consumption (81.0%), insufficient hydration (65.9%) and high levels of exposure to agrochemicals in the work environment (12.6%) were also observed. Prevalence of chronic kidney disease from nontraditional causes was 3.9% (men 6.1%; women 2.2%). CONCLUSIONS Chronic kidney disease has reached epidemic proportions in El Salvador. The data confirm a health tragedy that, although especially striking older men, also takes a severe toll on young men and women. The results confirm findings of previous research in several Salvadoran agricultural communities. The relatively high level of population exposure to agrochemicals is important and alarming, especially in rural areas, meriting health-impact studies that include and go beyond possible impact on chronic kidney disease. KEYWORDS Kidney, renal insufficiency, chronic, risk factors, epidemics, El Salvador.


Assuntos
Insuficiência Renal Crônica/epidemiologia , Adulto , Idoso , Análise por Conglomerados , Estudos Transversais , El Salvador/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco
15.
MEDICC Rev ; 21(4): 46-52, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-32335569

RESUMO

In El Salvador, chronic kidney disease had reached epidemic propor-tions towards the end of this century's first decade. In 2011-2012, the Ministry of Health reported it was the leading cause of hospital deaths in men, the fifth in women, and the third overall in adult hospital fa-talities. Farming was the most common occupation among men in dialysis (50.7%). By 2017, chronic kidney disease admissions had overwhelmed hospital capacity.In 2009, El Salvador's Ministry of Health, Cuba's Ministry of Public Health and PAHO launched a cooperative effort to comprehensively tackle the epidemic. The joint investigations revealed a total prevalence of chronic kidney disease in the adult population of farming communities higher than that reported internationally (18% vs.11%-14.8%), higher in men than in women (23.9% vs 13.9%) and higher in men who were farmers/farmworkers than in men who were not (31.3% vs. 14.8%). The disease was also detected in children. An association was found between chronic kidney disease and exposure to agrochemicals (OR 1.4-2.5). In 51.9% of all chronic kidney disease cases, traditional causes (diabetes, hyperten-sion, glomerulopathies, obstructive nephropathies and cystic diseases) were ruled out and the existence of a particular form of chronic kidney disease of nontraditional etiology was confirmed (whose initial cases were reported as early as 2002). In the patients studied, functional altera-tions and histopathologic diagnosis confirmed a chronic tubulointerstitial nephritis; most presented with neurosensory hearing loss, altered tendon refiexes and tibial artery damage. The main results of this cooperation were the epidemiologic, physio-pathologic, clinical and histopathologic characterization of chronic kid-ney disease of nontraditional etiology. This characterization facilitated case definition for the epidemic and led to the hypothesis of systemic toxicity from agrochemicals (e.g., paraquat, glyphosate), which par-ticularly affect the kidneys and to which farmers/farmworkers (who may also become dehydrated in the fields) are most exposed. The research thus also laid the foundations for design of comprehensive intersectoral government actions to reduce cases and put an end to the epidemic. KEYWORDS Chronic kidney disease; chronic renal failure; tubuloint-erstitial nephritis; epidemiology; histopathology; international coopera-tion; agrochemicals; environmental pollutants, noxae, and pesticides; occupational health; PAHO; El Salvador; Cuba.


Assuntos
Epidemias , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/etiologia , Adolescente , Criança , Pré-Escolar , Comportamento Cooperativo , Prestação Integrada de Cuidados de Saúde/tendências , El Salvador/epidemiologia , Epidemias/história , Feminino , História do Século XXI , Humanos , Masculino
16.
Front Microbiol ; 9: 2463, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30459723

RESUMO

The coli surface antigen 26 (CS26) of enterotoxigenic Escherichia coli (ETEC) had been described as a putative adhesive pilus based on the partial sequence of the crsH gene, detected in isolates from children with diarrhea in Egypt. However, its production and activity as adherence determinant has not been experimentally addressed. The crsH was identified as a homolog of genes encoding structural subunits of ETEC colonization factors (CFs) CS12, CS18, and CS20. These CFs, along with the recently discovered CS30, belong to the γ2 family of pili assembled by the chaperone-usher pathway (CU pili). Further, the complete CS26 locus, crsHBCDEFG, was described in an O141 ETEC strain (ETEC 100664) obtained from a diarrhea case in The Gambia, during the Global Enterics Multicenter Study. Here, we report that CS26 is a pilus of ∼10 nm in diameter, with the capacity to increase the cell adherence of the non-pathogenic strain E. coli DH10B. As for other related pili, production of CS26 seems to be regulated by phase variation. Deletion of crsHBCDEFG in ETEC 100664 significantly decreased its adherence capacity, which was recovered by in trans complementation. Furthermore, CrsH was cross-recognized by polyclonal antibodies directed against the major structural subunit of CS20, CsnA, as determined by Western blotting and immunogold labeling. ETEC CS26+ strains were found to harbor the heat-labile enterotoxin only, within three different sequence types of phylogroups A and B1, the latter suggesting acquisition through independent events of horizontal transfer. Overall, our results demonstrate that CS26 is an adhesive pilus of human ETEC. In addition, cross-reactivity with anti-CsnA antibodies indicate presence of common epitopes in γ2-CFs.

17.
Sci Rep ; 8(1): 5627, 2018 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-29618754

RESUMO

Climate change affects ecosystem functioning directly through impacts on plant physiology, resulting in changes of global productivity. However, climate change has also an indirect impact on ecosystems, through changes in the composition and diversity of plant communities. The relative importance of these direct and indirect effects has not been evaluated within a same generic approach yet. Here we took advantage of a novel approach for disentangling these two effects in European temperate forests across a large climatic gradient, through a large simulation-based study using a forest succession model. We first showed that if productivity positively correlates with realized tree species richness under a changed climate, indirect effects appear pivotal to understand the magnitude of climate change impacts on forest productivity. We further detailed how warmer and drier conditions may affect the diversity-productivity relationships (DPRs) of temperate forests in the long term, mostly through effects on species recruitment, ultimately enhancing or preventing complementarity in resource use. Furthermore, losing key species reduced the strength of DPRs more severely in environments that are becoming climatically harsher. By disentangling direct and indirect effects of climate change on ecosystem functioning, these findings explain why high-diversity forests are expected to be more resilient to climate change.


Assuntos
Biodiversidade , Mudança Climática , Ecossistema , Árvores/classificação , Árvores/fisiologia , Simulação por Computador , Florestas , Modelos Biológicos
18.
Rev. cuba. med ; 61(3)sept. 2022.
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1441676

RESUMO

Introducción: El trasplante renal es uno de los métodos de sustitución de la función renal y tiene como factor de mayor influencia en su supervivencia, la compatibilidad inmunológica del sistema mayor. Objetivos: Definir la supervivencia del trasplante y su relación con el grado de compatibilidad. Métodos: Se realizó un estudio retrospectivo sobre el tiempo de supervivencia con base hospitalaria de los 512 trasplantes en el período comprendido entre los años 1993 y 2010, ambos incluidos con seguimiento y corte al concluir el año 2019. Se empleó el Kaplan Meier para calcular las supervivencias, se utilizó el paquete estadístico Statiscal Package Social Science (Spss) versión 22.0. Resultados: 397 pacientes recibieron riñones cadavéricos al momento del corte, 11,3 por ciento de los injertos estaban funcionando, mientras que para los 115 que recibieron de vivo, el 45,2 por ciento, p=0,000. La mediana de supervivencia para el cadavérico fue de 3,1 años (SD 2,4-3,8) y dentro de ellos los que compartieron tres o más antígenos lograron el doble de sobrevida, p=0,033. Para el de donante vivo, la mediana fue de 16,0 años (SD 9,1-22,9) y dentro de este grupo 104 pacientes que compartían un haplotipo lograron 44,2 por ciento de función, los hermanos que eran idénticos un 66,0 por ciento. Por parentesco los que recibieron riñones de hermanos tienen mejor supervivencias que de padres a hijos, p=0,001. Conclusiones: Se definió que la compatibilidad inmunológica del sistema mayor entre donante y receptor propicia diferencias en la función de los injertos(AU)


Introduction: Renal transplantation is one of the methods of renal function substitution and the main factor influencing survival is the immunological compatibility of the major system. Objectives: To define transplant survival and the relationship with the degree of compatibility. Methods: A retrospective study was carried out on the hospital-based survival time of 512 transplants from 1993 to 2010, including follow-up and the cut at the end of 2019. The Kaplan-Meier estimator was used to calculate the survivals, the statistical package Statistical Package Social Science (Spss) version 22.0 was used. Results: Three hundred ninety seven (397) patients received cadaveric kidneys at the cut, 11.3percent of the grafts were functioning, 115 received living grafts, 45.2percent p=0.000. The median survival for the cadaveric kidneys was 3.1 years (SD 2.4-3.8) and among them those who shared three or more antigens achieved twice the survival, p=0.033. For the living donor, the median was 16.0 years (SD 9.1-22.9) and within this group, 104 patients, sharing a haplotype, achieved 44.2percent function, siblings, who were identical, achieved 66 .0percent. By kinship, those who received kidneys from siblings have better survival than for those who received it from parents, p=0.001. Conclusions: Immunological compatibility of the major system between donor and recipient was defined to favor differences in the function of the grafts(AU)


Assuntos
Humanos , Masculino , Feminino , Transplante de Rim/métodos , Sobrevivência , Estudos Retrospectivos
19.
Top Stroke Rehabil ; 24(6): 472-478, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28406071

RESUMO

BACKGROUND: Function in Sitting Test (FIST) is a clinical functional assessment of sitting balance validated in adults with stroke. For a major use of this, the test is recommended to be translated in Spanish-speaking countries. OBJECTIVES: Translate to Spanish the FIST and determine its intra-rater and inter-rater reliabilities and concurrent validity as a measure of sitting balance in adult individuals with stroke. METHODS: The original version was translated into Spanish and was agreed by a team of experts. A back-translation into English was subsequently performed and sent to the original author, who approved this version named from now Spanish version of Function in Sitting Test (S-FIST). Sixty post-stroke patients' performance was recorded on a videotape. These videos were then used to carry out four measurements to assess the intra-rater and inter-rater reliabilities; two of these were performed by the same rater and the third and fourth by a second and third rater. RESULTS: The S-FIST meets the following requirements: good construct validity and high correlation with Spanish version of Trunk Impairment Scale 2.0 (S-TIS 2.0) scores (r = 0.791) Spearman's rank, high internal consistency (Cronbach's α-coefficient = 0.97), and high intra-rater and inter-rater reliabilities for the summed scores assessed by intra-class correlation coefficient were 0.999 and 0.997, respectively. CONCLUSIONS: The S-FIST is valid and reliable and can be recommended for use in the evaluation of dynamic and sitting balance and trunk control in future research and clinical practice on post-stroke patients. Guidelines for treatment and level of quality of trunk activity can be derived from its use.


Assuntos
Avaliação de Resultados em Cuidados de Saúde/métodos , Equilíbrio Postural/fisiologia , Transtornos de Sensação/etiologia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/complicações , Tradução , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Transtornos de Sensação/reabilitação , Estatística como Assunto
20.
Adv Chronic Kidney Dis ; 24(2): 101-106, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28284375

RESUMO

Over the past 20 years, there has been an increase in chronic interstitial nephritis in agricultural communities (CINAC) not associated with traditional risk factors. This disease has become an important public health problem and is observed in several countries in Central America and Asia. CINAC predominantly affects young male farmers between the third and fifth decades of life with women, children, and adolescents less often affected. Clinically, CINAC behaves like a chronic tubulointerstitial nephropathy but with systemic manifestations not attributable to kidney disease. Kidney biopsy reveals chronic tubulointerstitial nephritis with variable glomerulosclerosis and mild chronic vascular damage, with the severity depending on sex, occupation, and CKD stage. The presence of toxicological, occupational, and environmental risk factors within these communities suggests a multifactorial etiology for CINAC. This may include exposure to agrochemicals, a contaminated environment, repeated episodes of dehydration with heat stress, and an underlying genetic predisposition. An understanding of these interacting factors using a multidisciplinary approach with international cooperation and the formulation of a comprehensive hypothesis are essential for the development of public health programs to prevent this devastating epidemic.


Assuntos
Agricultura , Nefrite Intersticial/epidemiologia , Nefrite Intersticial/etiologia , Exposição Ocupacional/efeitos adversos , Agroquímicos/toxicidade , Doença Crônica , Desidratação/complicações , Exposição Ambiental/efeitos adversos , Transtornos de Estresse por Calor/complicações , Humanos , Nefrite Intersticial/patologia , Saúde Ocupacional
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