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1.
Proc Natl Acad Sci U S A ; 121(6): e2305944121, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38252845

RESUMO

Protected areas are of paramount relevance to conserving wildlife and ecosystem contributions to people. Yet, their conservation success is increasingly threatened by human activities including habitat loss, climate change, pollution, and species overexploitation. Thus, understanding the underlying and proximate drivers of anthropogenic threats is urgently needed to improve protected areas' effectiveness, especially in the biodiversity-rich tropics. We addressed this issue by analyzing expert-provided data on long-term biodiversity change (last three decades) over 14 biosphere reserves from the Mesoamerican Biodiversity Hotspot. Using multivariate analyses and structural equation modeling, we tested the influence of major socioeconomic drivers (demographic, economic, and political factors), spatial indicators of human activities (agriculture expansion and road extension), and forest landscape modifications (forest loss and isolation) as drivers of biodiversity change. We uncovered a significant proliferation of disturbance-tolerant guilds and the loss or decline of disturbance-sensitive guilds within reserves causing a "winner and loser" species replacement over time. Guild change was directly related to forest spatial changes promoted by the expansion of agriculture and roads within reserves. High human population density and low nonfarming occupation were identified as the main underlying drivers of biodiversity change. Our findings suggest that to mitigate anthropogenic threats to biodiversity within biosphere reserves, fostering human population well-being via sustainable, nonfarming livelihood opportunities around reserves is imperative.


Assuntos
Biodiversidade , Ecossistema , Humanos , Animais , Agricultura , Animais Selvagens , Mudança Climática
2.
Proc Natl Acad Sci U S A ; 118(49)2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34845017

RESUMO

One-third of all Neotropical forests are secondary forests that regrow naturally after agricultural use through secondary succession. We need to understand better how and why succession varies across environmental gradients and broad geographic scales. Here, we analyze functional recovery using community data on seven plant characteristics (traits) of 1,016 forest plots from 30 chronosequence sites across the Neotropics. By analyzing communities in terms of their traits, we enhance understanding of the mechanisms of succession, assess ecosystem recovery, and use these insights to propose successful forest restoration strategies. Wet and dry forests diverged markedly for several traits that increase growth rate in wet forests but come at the expense of reduced drought tolerance, delay, or avoidance, which is important in seasonally dry forests. Dry and wet forests showed different successional pathways for several traits. In dry forests, species turnover is driven by drought tolerance traits that are important early in succession and in wet forests by shade tolerance traits that are important later in succession. In both forests, deciduous and compound-leaved trees decreased with forest age, probably because microclimatic conditions became less hot and dry. Our results suggest that climatic water availability drives functional recovery by influencing the start and trajectory of succession, resulting in a convergence of community trait values with forest age when vegetation cover builds up. Within plots, the range in functional trait values increased with age. Based on the observed successional trait changes, we indicate the consequences for carbon and nutrient cycling and propose an ecologically sound strategy to improve forest restoration success.


Assuntos
Conservação dos Recursos Naturais , Florestas , Modelos Biológicos , Clima Tropical
3.
Proc Biol Sci ; 290(1990): 20222203, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36629117

RESUMO

Abandonment of agricultural lands promotes the global expansion of secondary forests, which are critical for preserving biodiversity and ecosystem functions and services. Such roles largely depend, however, on two essential successional attributes, trajectory and recovery rate, which are expected to depend on landscape-scale forest cover in nonlinear ways. Using a multi-scale approach and a large vegetation dataset (843 plots, 3511 tree species) from 22 secondary forest chronosequences distributed across the Neotropics, we show that successional trajectories of woody plant species richness, stem density and basal area are less predictable in landscapes (4 km radius) with intermediate (40-60%) forest cover than in landscapes with high (greater than 60%) forest cover. This supports theory suggesting that high spatial and environmental heterogeneity in intermediately deforested landscapes can increase the variation of key ecological factors for forest recovery (e.g. seed dispersal and seedling recruitment), increasing the uncertainty of successional trajectories. Regarding the recovery rate, only species richness is positively related to forest cover in relatively small (1 km radius) landscapes. These findings highlight the importance of using a spatially explicit landscape approach in restoration initiatives and suggest that these initiatives can be more effective in more forested landscapes, especially if implemented across spatial extents of 1-4 km radius.


Assuntos
Ecossistema , Florestas , Biodiversidade , Árvores , Plantas
4.
Acta Paediatr ; 112(10): 2104-2112, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37332100

RESUMO

AIM: We examined the correlation between how long it took the parents of very low birthweight infants, born weighing up to 1500 g, to provide different kinds of autonomous care in a neonatal intensive care unit (NICU). METHODS: This prospective observational was conducted in the NICU of a Spanish hospital from 10 January 2020 to 3 May 2022. The unit had 11 beds single-family rooms and provided eight beds in an open bay room. The study examined breastfeeding, patient safety, participation in rounds, pain prevention and cleanliness. RESULTS: We studied 96 patients and their parents and there was no correlation between any type of care and the time it took parents to provide it autonomously. Parents in the single-family room cohort spent a median of 9.5 h per day between them in the NICU, while the parents in the open bay room spent 7.0 h with their infants (p = 0.03). However, parents in the single-family room group were able to recognise pain faster (p = 0.02). CONCLUSION: Parents in single-family rooms spent more time in the NICU and recognised pain faster but did not achieve autonomous care faster than parents in the open bay group.


Assuntos
Unidades de Terapia Intensiva Neonatal , Pais , Recém-Nascido , Feminino , Humanos , Lactente , Peso ao Nascer , Aleitamento Materno , Recém-Nascido de muito Baixo Peso
5.
Medicina (Kaunas) ; 59(6)2023 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-37374326

RESUMO

Objective: We aimed to evaluate the efficacy of the combination of atorvastatin and N-acetyl cysteine in increasing platelet counts in patients with immune thrombocytopenia who were resistant to steroid therapy or had a relapse after treatment. Material and Methods: The patients included in this study received oral treatment of atorvastatin at a dose of 40 mg daily and N-acetyl cysteine at a dose of 400 mg every 8 h. The desired treatment duration was 12 months, but we included patients who completed at least 1 month of treatment in the analysis. The platelet counts were measured prior to the administration of the study treatment and in the first, third, sixth, and twelfth months of treatment (if available). A p value < 0.05 was considered statistically significant. Results: We included 15 patients who met our inclusion criteria. For the total treatment duration, the global response was 60% (nine patients); eight patients (53.3%) had a complete response and one patient (6.7%) had a partial response. Six patients (40%) were considered as having undergone treatment failure. Of the responder group, five patients maintained a complete response after treatment (55.5%), three patients maintained a partial response (33.3%), and one patient (11.1%) lost their response to the treatment. All of the patients in the responder group had significant increases in their platelet counts after treatment (p < 0.05). Conclusion: This study provides evidence of a possible treatment option for patients with primary immune thrombocytopenia. However, further studies are needed.


Assuntos
Púrpura Trombocitopênica Idiopática , Trombocitopenia , Humanos , Acetilcisteína/farmacologia , Acetilcisteína/uso terapêutico , Atorvastatina/farmacologia , Atorvastatina/uso terapêutico , Contagem de Plaquetas , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Trombocitopenia/tratamento farmacológico , Resultado do Tratamento
6.
Medicina (Kaunas) ; 59(7)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37512152

RESUMO

Background and Objectives: Central aortic pressure (CAP) can be measured through noninvasive methods, and CAP wave analysis can provide information about arterial stiffness. The objective of this study was to compare CAP in women with preeclampsia and normotensive postpartum women from an urban region in western Mexico. Materials and Methods: We recruited 78 women in immediate puerperium, including 39 with preeclampsia and 39 with normotension, who received delivery care in our hospital between September 2017 and January 2018. Pulse wave analysis was used to assess central hemodynamics as well as arterial stiffness with an oscillometric device. For this purpose, the measurement of the wave of the left radial artery was obtained with a wrist applanation tonometer and the ascending aortic pressure wave was generated using the accompanying software (V 1.1, Omron, Japan). Additionally, the systolic CAP, diastolic pressure, pulse pressure, heart rate, and rise rate adjusted for a heart rate of 75 bpm were determined. The radial pulse wave was calibrated using the diastolic and mean arterial pressures obtained from the left brachial artery. For all the statistical analyses, we considered p < 0.05 to be significant. Results: The results were as follows: a systolic CAP of 125.40 (SD 15.46) vs. 112.10 (SD 10.12) with p < 0.0001 for women with and without preeclampsia, respectively. Systolic CAP was significantly elevated in women with preeclampsia and could indicate an elevated risk of cardiovascular disease. Conclusion: CAP is an important parameter that can be measured in this group of patients and is significantly elevated in women with postpartum preeclampsia, even when the brachial blood pressure is normal.


Assuntos
Pré-Eclâmpsia , Rigidez Vascular , Gravidez , Humanos , Feminino , Pressão Sanguínea , Pressão Arterial , México/epidemiologia , Período Pós-Parto , Rigidez Vascular/fisiologia , Análise de Onda de Pulso
7.
Medicina (Kaunas) ; 59(5)2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37241121

RESUMO

Background and Objectives: Our primary objective was to study the clinical and biochemical characteristics associated with acute kidney injury (AKI) remission in a group of Mexican patients. Materials and methods: We retrospectively enrolled 75 patients who were diagnosed with AKI and separated the sample into two groups: nonremitting patients (n = 27, 36%) vs. remitting patients (n = 48, 64%). Results: We found significant relationships between nonremitting AKI and previous diagnosis of chronic kidney disease (p = 0.009), higher serum creatinine (Cr) at admission (p < 0.0001), lower estimated glomerular filtration rate (eGFR) (p < 0.0001), maximum serum creatinine during hospitalization (p < 0.0001), higher fractional excretion of sodium (FENa) (p < 0.0003) and 24-h urine protein (p = 0.005), higher serum potassium on admission (p = 0.025), abnormal levels of procalcitonin (p = 0.006), and increased risk of death (p = 0.015). Conclusion: Chronic kidney disease (CKD), lower eGFR, higher levels of serum creatinine during hospitalization, higher FENa and 24-h urine protein, abnormal levels of procalcitonin, and higher serum potassium on admission were associated with nonremitting AKI. These findings may facilitate the rapid identification of patients at risk for nonremitting AKI based on clinical and biochemical characteristics. Furthermore, these findings may inform the design of timely strategies for the vigilance, prevention, and treatment of AKI.


Assuntos
Injúria Renal Aguda , Insuficiência Renal Crônica , Humanos , Estudos Retrospectivos , Creatinina , Pró-Calcitonina , Insuficiência Renal Crônica/complicações , Injúria Renal Aguda/complicações , Taxa de Filtração Glomerular
8.
Nature ; 530(7589): 211-4, 2016 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-26840632

RESUMO

Land-use change occurs nowhere more rapidly than in the tropics, where the imbalance between deforestation and forest regrowth has large consequences for the global carbon cycle. However, considerable uncertainty remains about the rate of biomass recovery in secondary forests, and how these rates are influenced by climate, landscape, and prior land use. Here we analyse aboveground biomass recovery during secondary succession in 45 forest sites and about 1,500 forest plots covering the major environmental gradients in the Neotropics. The studied secondary forests are highly productive and resilient. Aboveground biomass recovery after 20 years was on average 122 megagrams per hectare (Mg ha(-1)), corresponding to a net carbon uptake of 3.05 Mg C ha(-1) yr(-1), 11 times the uptake rate of old-growth forests. Aboveground biomass stocks took a median time of 66 years to recover to 90% of old-growth values. Aboveground biomass recovery after 20 years varied 11.3-fold (from 20 to 225 Mg ha(-1)) across sites, and this recovery increased with water availability (higher local rainfall and lower climatic water deficit). We present a biomass recovery map of Latin America, which illustrates geographical and climatic variation in carbon sequestration potential during forest regrowth. The map will support policies to minimize forest loss in areas where biomass resilience is naturally low (such as seasonally dry forest regions) and promote forest regeneration and restoration in humid tropical lowland areas with high biomass resilience.


Assuntos
Biomassa , Florestas , Árvores/crescimento & desenvolvimento , Clima Tropical , Carbono/metabolismo , Ciclo do Carbono , Sequestro de Carbono , Ecologia , Umidade , América Latina , Chuva , Fatores de Tempo , Árvores/metabolismo
9.
Transfus Med ; 32(2): 153-161, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35001439

RESUMO

INTRODUCTION: South America is one of the regions most affected by the COVID-19 pandemic. Specific and affordable treatments are needed to treat SARS-CoV-2 infection. Evidence regarding the use of convalescent plasma in COVID-19 patients is still limited. We compared the safety and efficacy of COVID-19-convalescent plasma administration as a complement to standard treatment in the early management of patients with moderate SARS-CoV-2 infection. METHODS: We carried out a random double blinded, placebo-controlled trial that compared standard treatment plus convalescent plasma (CP) or plus non-convalescent plasma in the management of COVID-19 patients. The main outcome was survival and secondary endpoints included: length of hospitalisation (LOH), days from treatment to discharge, time to clinical improvement or death within a 28-day period, and adverse reactions to treatment. RESULTS: Administration of CP with antibodies against SARS-CoV-2 did not affect patient survival, RR = 1.003, 95% CI (0.3938, 2.555). These results led to terminate the RCT prematurely. However, early treatment of COVID-19 patients with CP tended to decrease the LOH while the delay in CP treatment was associated with longer hospitalisation. In addition, delay in CP treatment negatively affected the recovery of the respiratory rate. CONCLUSION: Use of CP for the treatment of COVID-19 patients is safe and its early use can decrease the LOH and improve respiratory function. Early administration of antibody-rich CP could contribute to decrease the negative impact of COVID-19 pandemic in patients with impaired immune response.


Assuntos
COVID-19 , Imunização Passiva , COVID-19/terapia , Humanos , Imunização Passiva/métodos , Pandemias , SARS-CoV-2 , Soroterapia para COVID-19
10.
Dis Colon Rectum ; 64(12): 1521-1530, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34747917

RESUMO

BACKGROUND: Chemical sphincterotomy avoids the risk of permanent incontinence in the treatment of chronic anal fissure, but it does not reach the efficacy of surgery and recurrence is high. Drug combination has been proposed to overcome these drawbacks. OBJECTIVE: This study aimed to compare the clinical, morphological, and functional effects of combined therapy with botulinum toxin injection and topical diltiazem in chronic anal fissure and to assess the long-term outcome after healing. DESIGN: This is a randomized, controlled, double-blind, 2-arm, parallel-group trial with a long-term follow-up. SETTINGS: This study was conducted at a tertiary care center. PATIENTS: A total of 70 consecutive patients were referred to the gastroenterology department of a hospital in Valencia, Spain. INTERVENTION: After botulinum toxin injection (20 IU), patients were randomly assigned to local diltiazem (diltiazem group) or placebo gel (placebo group) for 12 weeks. MAIN OUTCOME MEASURES: The primary outcome was fissure healing (evaluated by video register by 3 independent physicians). Secondary outcomes included symptomatic relief (30-day diary), effect on anal sphincters (manometry), safety, and long-term recurrence (24 months and 10 years). RESULTS: Healing was achieved per protocol in 13 of 25 (52%) patients of the diltiazem group and 11 of 30 (36.7%) patients of the placebo group (p = 0.25); on an intention-to-treat basis in 37.1% and 31.4% (p = 0.61). Both groups displayed significant reduction of anal pressures. Thirty percent reported minor and transitory incontinence, without differences between groups. Nine (69.2%) of the diltiazem group and 6 (54.5%) of the placebo group experienced a relapse at 24 months (p = 0.67). The overall recurrence rate at 10 years was 83.3% (20/24 patients). LIMITATIONS: This study was limited by the loss of patients during the trial. The low healing rate led to a small cohort to assess recurrence. CONCLUSIONS: Combined botulinum toxin injection and topical diltiazem is not superior to botulinum toxin injection in the treatment of chronic anal fissure. Both options offer suboptimal healing rates. Long-term recurrence is high (>80% at 10 years) and might appear at any time after healing. See Video Abstract at http://links.lww.com/DCR/B527. INYECCIN DE TOXINA BOTULNICA MS DILTIAZEM TPICO EN FISURA ANAL CRNICA UN ENSAYO CLNICO ALEATORIZADO DOBLE CIEGO Y RESULTADOS A LARGO PLAZO: ANTECEDENTES:La esfinterotomía química evita el riesgo de incontinencia permanente en el tratamiento de la fisura anal crónica, pero no alcanza la eficacia de la cirugía y la recurrencia es alta. Se ha propuesto la combinación de fármacos para superar estos inconvenientes.OBJETIVO:Comparar los efectos clínicos, morfológicos y funcionales de la terapia combinada con inyección de toxina botulínica y diltiazem tópico en fisura anal crónica y evaluar el resultado a largo plazo después de la cicatrización.DISEÑO:Ensayo aleatorizado, controlado, doble ciego, de dos brazos, de grupos paralelos con un seguimiento a largo plazo.ESCENARIO:Estudio realizado en un centro de atención terciaria.PACIENTES:Un total de 70 pacientes consecutivos referidos al servicio de gastroenterología de un hospital de Valencia, España.INTERVENCIÓN:Después de la inyección de toxina botulínica (20UI), los pacientes fueron asignados al azar a diltiazem local (grupo de diltiazem) o gel de placebo (grupo de placebo) durante 12 semanas.PRINCIPALES MEDIDAS DE RESULTADO:El resultado primario fue la cicatrización de la fisura (evaluado por registro de video por tres médicos independientes). Los resultados secundarios incluyeron alivio sintomático (diario de 30 días), efecto sobre los esfínteres anales (manometría), seguridad y recurrencia a largo plazo (24 meses y 10 años).RESULTADOS:La curación se logró por protocolo en 13/25 (52%) en el grupo de Diltiazem y 11/30 (36,7%) en el grupo de Placebo (p = 0.25); por intención de tratar en el 37.1% y el 31.4%, respectivamente (p = 0.61). Ambos grupos mostraron una reducción significativa de las presiones anales. El 30% refirió incontinencia leve y transitoria, sin diferencias entre grupos. 9 (69.2%) del grupo de Diltiazem y 6 (54.5%) del grupo de placebo recurrieron a los 24 meses (p = 0.67). La tasa global de recurrencia a los 10 años fue del 83.3% (20/24 pacientes).LIMITACIONES:La pérdida de pacientes a lo largo del ensayo. La baja tasa de curación llevó a una pequeña cohorte para evaluar la recurrencia.CONCLUSIONES:La inyección combinada de toxina botulínica y diltiazem tópico no es superior a la inyección de TB en el tratamiento de la fisura anal crónica. Ambas opciones ofrecen tasas de curación subóptimas. La recurrencia a largo plazo es alta (> 80% a los 10 años) y puede aparecer en cualquier momento después de la curación. Consulte Video Resumen en http://links.lww.com/DCR/B527.


Assuntos
Toxinas Botulínicas/uso terapêutico , Diltiazem/uso terapêutico , Fissura Anal/tratamento farmacológico , Neurotoxinas/uso terapêutico , Vasodilatadores/uso terapêutico , Administração Tópica , Adulto , Canal Anal/efeitos dos fármacos , Canal Anal/fisiopatologia , Toxinas Botulínicas/administração & dosagem , Estudos de Casos e Controles , Doença Crônica , Diltiazem/administração & dosagem , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Injeções/métodos , Masculino , Manometria/métodos , Pessoa de Meia-Idade , Neurotoxinas/administração & dosagem , Placebos/administração & dosagem , Recidiva , Espanha/epidemiologia , Centros de Atenção Terciária , Resultado do Tratamento , Vasodilatadores/administração & dosagem , Cicatrização/efeitos dos fármacos
11.
Proc Natl Acad Sci U S A ; 115(8): 1837-1842, 2018 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-29432167

RESUMO

Knowledge about the biogeographic affinities of the world's tropical forests helps to better understand regional differences in forest structure, diversity, composition, and dynamics. Such understanding will enable anticipation of region-specific responses to global environmental change. Modern phylogenies, in combination with broad coverage of species inventory data, now allow for global biogeographic analyses that take species evolutionary distance into account. Here we present a classification of the world's tropical forests based on their phylogenetic similarity. We identify five principal floristic regions and their floristic relationships: (i) Indo-Pacific, (ii) Subtropical, (iii) African, (iv) American, and (v) Dry forests. Our results do not support the traditional neo- versus paleotropical forest division but instead separate the combined American and African forests from their Indo-Pacific counterparts. We also find indications for the existence of a global dry forest region, with representatives in America, Africa, Madagascar, and India. Additionally, a northern-hemisphere Subtropical forest region was identified with representatives in Asia and America, providing support for a link between Asian and American northern-hemisphere forests.


Assuntos
Florestas , Filogenia , Plantas/classificação , Plantas/genética , Clima Tropical , Biodiversidade , Conservação dos Recursos Naturais , Monitoramento Ambiental
12.
Ann Bot ; 126(5): 957-969, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33026086

RESUMO

BACKGROUND AND AIMS: The implications of herbivory for plant reproduction have been widely studied; however, the relationship of defoliation and reproductive success is not linear, as there are many interacting factors that may influence reproductive responses to herbivore damage. In this study we aimed to disentangle how the timing of foliar damage impacts both male and female components of fitness, and to assess when it has greater impacts on plant reproductive success. METHODS: We measured herbivore damage and its effects on floral production, male and female floral attributes as well as fruit yield in three different phenological phases of Casearia nitida (Salicaceae) over the course of two consecutive years. Then we tested two models of multiple causal links among herbivory and reproductive success using piecewise structural equation models. KEY RESULTS: The effects of leaf damage differed between reproductive seasons and between male and female components of fitness. Moreover, the impact of herbivory extended beyond the year when it was exerted. The previous season's cumulated foliar damage had the largest impact on reproductive characters, in particular a negative effect on the numbers of inflorescences, flowers and pollen grains, indirectly affecting the numbers of infructescences and fruits, and a positive one on the amount of foliar damage during flowering. CONCLUSIONS: For perennial and proleptic species, the dynamics of resource acquisition and allocation patterns for reproduction promote and extend the effects of herbivore damage to longer periods than a single reproductive event and growing season, through the interactions among different components of female and male fitness.


Assuntos
Herbivoria , Árvores , Feminino , Flores , Folhas de Planta , Reprodução
13.
Int J Colorectal Dis ; 35(3): 491-500, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31915983

RESUMO

PURPOSE: Recognizing patients with inflammatory bowel disease who are prone to infection would enable the adjustment of the type and intensity of immunosuppressive treatment. The aim of this study was to identify a clinical profile of risk for infections in IBD patients, based on the interaction of immunosuppressive treatment with factors inherent to the patient. METHODS: A case-control study was performed among patients older than 18 years. Patients with any significant infection (any kind of severe or recurrent infection according to standard clinical criteria or a critical enough infection according to the patient) were defined as cases. Both cases and controls were randomly selected in a 1:3 ratio. All the period from diagnosis to the end of recruitment (June 2016) was analyzed. Risk factors for infection were identified by logistic regression analysis; the strength of association was reported by odds ratio (OR) with 95% confidence interval (95%CI). RESULTS: A total of 112 cases and 270 controls were included. The independent risk factors for significant infection are the number of immunosuppressants (one drug: OR 1.28, 95% CI 0.53-3.11, two drugs: OR 2.37, 95% CI 1.01-5,56, and three drugs: OR 5.84, 95% CI 1.57-21.72), body mass index (OR 1.08; 95 %CI 1,01-1,16), the degree of comorbidity (OR 1.52; 95% CI 1.04-2.21), and the intensity of inflammatory activity (OR 1.43; 95% CI 1.19-1.71). CONCLUSIONS: Regardless of immunosuppression, several patient factors such as comorbidity, body mass index, or the inflammatory activity of the disease determine the individual risk of infectious complications and should be considered for an adequate risk assessment.


Assuntos
Imunossupressores/efeitos adversos , Infecções/etiologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/imunologia , Índice de Massa Corporal , Estudos de Casos e Controles , Suscetibilidade a Doenças , Humanos , Doenças Inflamatórias Intestinais/complicações , Fatores de Risco
14.
New Phytol ; 223(2): 896-907, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30891762

RESUMO

It has been suggested that plant carbon (C) use by symbiotic arbuscular mycorrhizal fungi (AMF) may be compensated by higher photosynthetic rates because fungal metabolism creates a strong C sink that prevents photosynthate accumulation and downregulation of photosynthesis. This mechanism remains largely unexplored and lacks experimental evidence. We report here two experiments showing that the experimental manipulation of the mycorrhizal C sink significantly affected the photosynthetic rates of cucumber host plants. We expected that a sudden reduction in sink strength would cause a significant reduction in photosynthetic rates, at least temporarily. Excision of part of the extraradical mycorrhizal mycelium from roots, and causing no disturbance to the plant, induced a sustained (10-40%) decline in photosynthetic rates that lasted from 30 min to several hours in plants that were well-nourished and hydrated, and in the absence of growth or photosynthesis promotion by mycorrhizal inoculation. This effect was though minor in plants growing at high (700 ppm) atmospheric CO2 . This is the first direct experimental evidence for the C sink strength effects exerted by arbuscular mycorrhizal symbionts on plant photosynthesis. It encourages further experimentation on mycorrhizal source-sink relations, and may have strong implications in large-scale assessments and modelling of plant photosynthesis.


Assuntos
Sequestro de Carbono , Micorrizas/fisiologia , Fotossíntese , Dióxido de Carbono/metabolismo , Cucumis sativus/microbiologia , Cucumis sativus/fisiologia , Modelos Lineares , Modelos Biológicos , Micélio/fisiologia , Estômatos de Plantas/fisiologia , Fatores de Tempo
15.
J Card Fail ; 25(5): 319-327, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30347272

RESUMO

BACKGROUND: Recent evidence endorses gut microbiota dysregulation in the pathophysiology of heart failure (HF). Small intestinal bacterial overgrowth (SIBO) might be present in HF and associated with poor clinical outcomes. Lactulose breath testing is a simple noninvasive test that has been advocated as a reliable indicator of SIBO. In patients with HF, we aimed to evaluate the association with clinical outcomes of the exhaled hydrogen (H2) and methane (CH4) concentrations through the lactulose breath test. METHODS AND RESULTS: We included 102 patients with HF in which lactulose SIBO breath tests were assessed. Cumulative gas was quantified by the area under the receiver operating characteristic curve of CH4 (AUC-CH4) and H2 (AUC-H2). Clinical end points included the composite of all-cause death with either all-cause or HF hospitalizations, recurrent all-cause hospitalizations, and recurrent HF hospitalizations. Medians (interquartile ranges) of AUC-H2 and AUC-CH4 were 1290 U (520-2430) and 985 U (450-2120), respectively. In multivariable analysis, AUC-H2 (per 1000 U) was associated with all-cause death/all-cause hospitalization (hazard ratio [HR] 1.21, 95% CI 1.04-1.40; P = .012), all-cause death/HF hospitalization (HR 1.20, 95% CI 1.03-1.40; P = .021), and an increase in the rate of recurrent all-cause (incidence rate ratio [IRR] 1.31, 95% CI 1.14-1.51; P < .001) and HF (IRR 1.41, 95% CI 1.15-1.72; P = .001) hospitalizations. AUC-CH4 was not associated with any of these end points. CONCLUSIONS: AUC-H2, a safe and noninvasive method for SIBO estimation, is associated with higher risk of long-term adverse clinical events in patients with HF. In contrast, AUC-CH4 did not show any prognostic value.


Assuntos
Testes Respiratórios , Insuficiência Cardíaca/mortalidade , Hospitalização/estatística & dados numéricos , Hidrogênio/análise , Metano/análise , Idoso , Idoso de 80 Anos ou mais , Bactérias/crescimento & desenvolvimento , Expiração , Feminino , Seguimentos , Microbioma Gastrointestinal , Humanos , Intestino Delgado/microbiologia , Masculino , Estudos Prospectivos
16.
Pancreatology ; 19(5): 623-629, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31229460

RESUMO

BACKGROUND: Previous publications have reported an association between hypertriglyceridemia (HTG) and severity of acute pancreatitis, but this relationship remains somewhat controversial. OBJECTIVE: To evaluate the outcome of acute pancreatitis according to serum triglyceride levels on admission. METHODS: Retrospective analysis of prospectively collected data, which included all consecutive cases of acute pancreatitis admitted to a tertiary hospital (January 2002-December 2014). Acute pancreatitis patients were classified into 3 groups based on serum triglyceride levels (mg/dl) measured within 48 h from admission: normal triglycerides-mild HTG (<200); moderate HTG (200-749); severe HTG (≥750). Primary outcomes were the difference in organ failure, pancreatic necrosis, acute peripancreatic collections and mortality among the three groups. RESULTS: A total of 1,457 cases were included: 1,335 with normal-mild HTG, 77 with moderate HTG and 45 with severe HTG. The rates of organ failure (11.2% in normal-mild HTG group, 15.6% in moderate HTG and 20.0% in severe HTG), persistent multiple organ failure (2.5% vs. 5.2% vs. 6.7%), pancreatic necrosis (9.2% vs. 14.3% vs. 26.7%) and acute collections (21.6% vs. 40.3% vs. 55.6%) increased significantly with hypertriglyceridemia severity grades. On multivariate analysis, triglycerides as a quantitative variable, evaluated in increments of 100 mg/dl, was independently associated with organ failure, pancreatic necrosis, acute collections and mortality (p < 0.05). CONCLUSIONS: Elevated serum triglyceride levels are independently associated with a more severe course of pancreatitis. It must be highlighted the elevated frequency of local complications in patients with HTG that increases proportionally and significantly with HTG severity grades.


Assuntos
Hipertrigliceridemia/sangue , Pancreatite/sangue , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Hipertrigliceridemia/complicações , Hipertrigliceridemia/mortalidade , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/mortalidade , Pâncreas/patologia , Pancreatite/complicações , Pancreatite/mortalidade , Pancreatite Necrosante Aguda/sangue , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Triglicerídeos/sangue , Adulto Jovem
17.
Transpl Infect Dis ; 20(4): e12904, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29668074

RESUMO

BACKGROUND: Nocardiosis is a life-threatening opportunistic infection. Solid organ transplant (SOT) recipients are at higher risk (incidence 0.04%-3.5%) of developing nocardiosis. Rate of nocardiosis in the Southwestern US may be high due to environmental factors. METHODS: We performed a retrospective review study on 54 SOT patients diagnosed with Nocardia between 1997 and 2016 at our center. To explore the association of various risk factors with both the development of disseminated disease and mortality, a series of Fisher's exact tests was used. FINDINGS: Incidence of nocardiosis in SOT patients was 2.65%. Fisher's exact tests revealed no association between development of disseminated disease and the following variables: transplant rejection (P = 1), elevated tacrolimus levels (P = .4), and CMV viremia (P = .06). Also, we did not find any association between mortality and the variables we evaluated: type of transplant, transplant rejection, renal failure, disseminated nocardia, and patient's age. Overall mortality and 1-year mortality were 17% and 11%. INTERPRETATION: Based on our findings, daily 1 DS TMP/SMX prophylaxis did not appear to provide reliable protection against nocardiosis. However, we could not state definitely that TMP/SMX prophylaxis was or wasn't protective because of lack control group. None of the Fisher's exact tests revealed associations between the tested risk factors and either disease dissemination or mortality. This could be due to a true lack of association between the variables in each pair. However, it is also likely that our relatively small sample size limited our power to detect underlying relationships that may be present. Compared with other studies, 1-year mortality was lower at our institution (11% vs 16%).


Assuntos
Rejeição de Enxerto/epidemiologia , Nocardiose/epidemiologia , Nocardia/isolamento & purificação , Infecções Oportunistas/epidemiologia , Transplante de Órgãos/efeitos adversos , Adulto , Idoso , Antibacterianos/uso terapêutico , Feminino , Rejeição de Enxerto/prevenção & controle , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/efeitos adversos , Incidência , Masculino , Pessoa de Meia-Idade , Nocardiose/imunologia , Nocardiose/microbiologia , Nocardiose/prevenção & controle , Infecções Oportunistas/imunologia , Infecções Oportunistas/microbiologia , Infecções Oportunistas/prevenção & controle , Estudos Retrospectivos , Fatores de Risco , Sudoeste dos Estados Unidos/epidemiologia , Tacrolimo , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Adulto Jovem
18.
Int J Colorectal Dis ; 32(8): 1197-1205, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28361220

RESUMO

PURPOSE: Several studies demonstrate an increased prevalence and concordance of inflammatory bowel disease among the relatives of patients. Other studies suggest that genetic influence is over-estimated. The aims of this study are to evaluate the phenotypic expression and the treatment requirements in familial inflammatory bowel disease, to study the relationship between number of relatives and degree of kinship with disease severity and to quantify the impact of family aggregation compared to other environmental factors. METHODS: Observational analytical study of 1211 patients followed in our unit. We analyzed, according to the existence of familial association, number and degree of consanguinity, the phenotypic expression, complications, extraintestinal manifestations, treatment requirements, and mortality. A multivariable analysis considering smoking habits and non-steroidal-anti-inflammatory drugs was performed. RESULTS: 14.2% of patients had relatives affected. Median age at diagnosis tended to be lower in the familial group, 32 vs 29, p = 0.07. In familial ulcerative colitis, there was a higher proportion of extraintestinal manifestations: peripheral arthropathy (OR = 2.3, p = 0.015) and erythema nodosum (OR = 7.6, p = 0.001). In familial Crohn's disease, there were higher treatment requirements: immunomodulators (OR = 1.8, p = 0.029); biologics (OR = 1.9, p = 0.011); and surgery (OR = 1.7, p = 0.044). The abdominal abscess increased with the number of relatives affected: 5.1% (sporadic), 7.0% (one), and 14.3% (two or more), p=0.039. These associations were maintained in the multivariate analysis. CONCLUSIONS: Familial aggregation is considered a risk factor for more aggressive disease and higher treatment requirements, a tendency for earlier onset, more abdominal abscess, and extraintestinal manifestations, remaining a risk factor analyzing the influence of some environmental factors.


Assuntos
Doenças Inflamatórias Intestinais/patologia , Doenças Inflamatórias Intestinais/terapia , Índice de Gravidade de Doença , Adulto , Anti-Inflamatórios não Esteroides/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/patologia , Doença de Crohn/tratamento farmacológico , Doença de Crohn/patologia , Família , Feminino , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Masculino , Análise Multivariada , Fumar/efeitos adversos , Adulto Jovem
20.
Int J Colorectal Dis ; 30(5): 613-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25612521

RESUMO

AIM: Transanal advancement flap is a recognized technique for complex fistula. Management of the tract is open to discussion. Excision of the tract by the "core out" technique is difficult and could increase the risk of sphincter damage. Curettage is easier but it could increase the risk of recurrence. The aim of the present study was to assess the effect of both techniques on sphincter function and to study the clinical results. METHOD: This is a retrospective analysis from a prospective database. One hundred nineteen consecutive patients with high cryptoglandular anal fistula were included. "Core out" technique was performed in 78 patients (group I) and "curettage" in 41 (group II). In both, a full-thickness rectal flap was advanced over the closed internal defect. Anorectal manometry was performed to assess sphincter function. Continence was assessed using the Wexner Scale. Recurrence was defined as the presence of an abscess or fistulization. RESULTS: Manometric results showed a significant decrease in the maximum resting pressure after surgery in both groups. The maximum squeeze pressure was significantly reduced only in group I (p < 0.001). No significant changes in Wexner score were observed. The overall recurrence rate was 5.88%, five of group I (6.4%) and two of group II (4.9%), without statistical significance (p = 0.74). CONCLUSIONS: The core-out technique causes a significant decrease in squeeze pressures, which reflects damage to the external anal sphincter. This could lead to incontinence in high-risk patients. Curettage is a simple technique that preserves the values of squeeze pressures without increasing recurrence rates.


Assuntos
Curetagem/métodos , Fístula Retal/cirurgia , Retalhos Cirúrgicos , Adulto , Canal Anal/cirurgia , Bases de Dados Factuais , Incontinência Fecal/prevenção & controle , Feminino , Seguimentos , Humanos , Masculino , Manometria/métodos , Pessoa de Meia-Idade , Satisfação do Paciente/estatística & dados numéricos , Procedimentos de Cirurgia Plástica/métodos , Fístula Retal/diagnóstico , Recidiva , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Resultado do Tratamento , Cicatrização/fisiologia
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