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1.
Nature ; 612(7939): 277-282, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36323786

RESUMO

The forested swamps of the central Congo Basin store approximately 30 billion metric tonnes of carbon in peat1,2. Little is known about the vulnerability of these carbon stocks. Here we investigate this vulnerability using peat cores from a large interfluvial basin in the Republic of the Congo and palaeoenvironmental methods. We find that peat accumulation began at least at 17,500 calibrated years before present (cal. yr BP; taken as AD 1950). Our data show that the peat that accumulated between around 7,500 to around 2,000 cal. yr BP is much more decomposed compared with older and younger peat. Hydrogen isotopes of plant waxes indicate a drying trend, starting at approximately 5,000 cal. yr BP and culminating at approximately 2,000 cal. yr BP, coeval with a decline in dominant swamp forest taxa. The data imply that the drying climate probably resulted in a regional drop in the water table, which triggered peat decomposition, including the loss of peat carbon accumulated prior to the onset of the drier conditions. After approximately 2,000 cal. yr BP, our data show that the drying trend ceased, hydrologic conditions stabilized and peat accumulation resumed. This reversible accumulation-loss-accumulation pattern is consistent with other peat cores across the region, indicating that the carbon stocks of the central Congo peatlands may lie close to a climatically driven drought threshold. Further research should quantify the combination of peatland threshold behaviour and droughts driven by anthropogenic carbon emissions that may trigger this positive carbon cycle feedback in the Earth system.


Assuntos
Carbono , Solo , Congo
2.
Am J Physiol Heart Circ Physiol ; 327(1): H182-H190, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38787386

RESUMO

Murray's law has been viewed as a fundamental law of physiology. Relating blood flow ([Formula: see text]) to vessel diameter (D) ([Formula: see text]·âˆ·D3), it dictates minimum lumen area (MLA) targets for coronary bifurcation percutaneous coronary intervention (PCI). The cubic exponent (3.0), however, has long been disputed, with alternative theoretical derivations, arguing this should be closer to 2.33 (7/3). The aim of this meta-analysis was to quantify the optimum flow-diameter exponent in human and mammalian coronary arteries. We conducted a systematic review and meta-analysis of all articles quantifying an optimum flow-diameter exponent for mammalian coronary arteries within the Cochrane library, PubMed Medline, Scopus, and Embase databases on 20 March 2023. A random-effects meta-analysis was used to determine a pooled flow-diameter exponent. Risk of bias was assessed with the National Institutes of Health (NIH) quality assessment tool, funnel plots, and Egger regression. From a total of 4,772 articles, 18 were suitable for meta-analysis. Studies included data from 1,070 unique coronary trees, taken from 372 humans and 112 animals. The pooled flow diameter exponent across both epicardial and transmural arteries was 2.39 (95% confidence interval: 2.24-2.54; I2 = 99%). The pooled exponent of 2.39 showed very close agreement with the theoretical exponent of 2.33 (7/3) reported by Kassab and colleagues. This exponent may provide a more accurate description of coronary morphometric scaling in human and mammalian coronary arteries, as compared with Murray's original law. This has important implications for the assessment, diagnosis, and interventional treatment of coronary artery disease.


Assuntos
Circulação Coronária , Vasos Coronários , Animais , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Vasos Coronários/diagnóstico por imagem , Modelos Cardiovasculares , Intervenção Coronária Percutânea
3.
Surg Endosc ; 38(7): 3645-3653, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38772960

RESUMO

BACKGROUND: The field of robotic-assisted surgery is rapidly growing as many robotic surgical devices are in development and about to enter the market. Currently, there is no universally accepted language for labeling the different robotic systems. To facilitate this communication, we created what is, to our knowledge, the first classification of surgical robotic technologies that organizes and classifies surgical robots used for endoscopy, laparoscopy and thoracoscopy. METHODS: We compiled a list of surgical robots intended to be used for endoscopy, laparoscopy, and/or thoracoscopy by searching United States, European, Hong Kong, Japan, and Korean databases for approved devices. Devices showcased at the 2023 Annual Meeting for the Society of Robotic Surgery were added. We also systematically reviewed the literature for any existing surgical robotic classifications or categorizations. We then created a multidisciplinary committee of 8 surgeons and 2 engineers to construct a proposed classification of the devices included in our search. RESULTS: We identified 40 robotic surgery systems intended to be used for endoscopy, laparoscopy and/or thoracoscopy. The proposed classification organizes robotic devices with regard to architecture, port design, and configuration (modular carts, multi-arm integrated cart, table-attachable or arm-table integration). CONCLUSION: This 3-level classification of robotic surgical devices used for endoscopy, laparoscopy and/or thoracoscopy describes important characteristics of robotic devices systematically.


Assuntos
Laparoscopia , Procedimentos Cirúrgicos Robóticos , Toracoscopia , Procedimentos Cirúrgicos Robóticos/instrumentação , Procedimentos Cirúrgicos Robóticos/métodos , Humanos , Laparoscopia/métodos , Toracoscopia/métodos , Desenho de Equipamento , Endoscopia/métodos
4.
Proc Natl Acad Sci U S A ; 118(48)2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34815344

RESUMO

Carriers of heterozygous germline BAP1 mutations (BAP1+/-) are affected by the "BAP1 cancer syndrome." Although they can develop almost any cancer type, they are unusually susceptible to asbestos carcinogenesis and mesothelioma. Here we investigate why among all carcinogens, BAP1 mutations cooperate with asbestos. Asbestos carcinogenesis and mesothelioma have been linked to a chronic inflammatory process promoted by the extracellular release of the high-mobility group box 1 protein (HMGB1). We report that BAP1+/- cells secrete increased amounts of HMGB1, and that BAP1+/- carriers have detectable serum levels of acetylated HMGB1 that further increase when they develop mesothelioma. We linked these findings to our discovery that BAP1 forms a trimeric protein complex with HMGB1 and with histone deacetylase 1 (HDAC1) that modulates HMGB1 acetylation and its release. Reduced BAP1 levels caused increased ubiquitylation and degradation of HDAC1, leading to increased acetylation of HMGB1 and its active secretion that in turn promoted mesothelial cell transformation.


Assuntos
Amianto , Proteína HMGB1/química , Histona Desacetilase 1/química , Proteínas Supressoras de Tumor/química , Ubiquitina Tiolesterase/química , Animais , Biomarcadores Tumorais/metabolismo , Carcinogênese , Núcleo Celular/metabolismo , Feminino , Interação Gene-Ambiente , Mutação em Linhagem Germinativa , Proteína HMGB1/genética , Heterozigoto , Histona Desacetilase 1/genética , Incidência , Inflamação , Masculino , Mesotelioma/metabolismo , Camundongos , Mutação , Prognóstico , Ligação Proteica , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina/química , Ubiquitina Tiolesterase/metabolismo
5.
Glob Chang Biol ; 29(23): 6812-6827, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37815703

RESUMO

Peatlands of the central Congo Basin have accumulated carbon over millennia. They currently store some 29 billion tonnes of carbon in peat. However, our understanding of the controls on peat carbon accumulation and loss and the vulnerability of this stored carbon to climate change is in its infancy. Here we present a new model of tropical peatland development, DigiBog_Congo, that we use to simulate peat carbon accumulation and loss in a rain-fed interfluvial peatland that began forming ~20,000 calendar years Before Present (cal. yr BP, where 'present' is 1950 CE). Overall, the simulated age-depth curve is in good agreement with palaeoenvironmental reconstructions derived from a peat core at the same location as our model simulation. We find two key controls on long-term peat accumulation: water at the peat surface (surface wetness) and the very slow anoxic decay of recalcitrant material. Our main simulation shows that between the Late Glacial and early Holocene there were several multidecadal periods where net peat and carbon gain alternated with net loss. Later, a climatic dry phase beginning ~5200 cal. yr BP caused the peatland to become a long-term carbon source from ~3975 to 900 cal. yr BP. Peat as old as ~7000 cal. yr BP was decomposed before the peatland's surface became wetter again, suggesting that changes in rainfall alone were sufficient to cause a catastrophic loss of peat carbon lasting thousands of years. During this time, 6.4 m of the column of peat was lost, resulting in 57% of the simulated carbon stock being released. Our study provides an approach to understanding the future impact of climate change and potential land-use change on this vulnerable store of carbon.


Assuntos
Carbono , Áreas Alagadas , Congo , Solo , Ciclo do Carbono
6.
BMC Med Res Methodol ; 23(1): 79, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-37013490

RESUMO

BACKGROUND: In network meta-analysis, estimation of a comparative effect can be performed for treatments that are connected either directly or indirectly. However, disconnected trial networks may arise, which poses a challenge to comparing all available treatments of interest. Several modeling approaches attempt to compare treatments from disconnected networks but not without strong assumptions and limitations. Conducting a new trial to connect a disconnected network can enable calculation of all treatment comparisons and help researchers maximize the value of the existing networks. Here, we develop an approach to finding the best connecting trial given a specific comparison of interest. METHODS: We present formulas to quantify the variation in the estimation of a particular comparative effect of interest for any possible connecting two-arm trial. We propose a procedure to identify the optimal connecting trial that minimizes this variation in effect estimation. RESULTS: We show that connecting two treatments indirectly might be preferred to direct connection through a new trial, by leveraging information from the existing disconnected networks. Using a real network of studies on the use of vaccines in the treatment of bovine respiratory disease (BRD), we illustrate a procedure to identify the best connecting trial and confirm our findings via simulation. CONCLUSION: Researchers wishing to conduct a connecting two-arm study can use the procedure provided here to identify the best connecting trial. The choice of trial that minimizes the variance of a comparison of interest is network dependent and it is possible that connecting treatments indirectly may be preferred to direct connection.


Assuntos
Projetos de Pesquisa , Animais , Bovinos , Humanos , Metanálise em Rede , Simulação por Computador
7.
Nature ; 546(7659): 549-553, 2017 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-28614305

RESUMO

BRCA1-associated protein 1 (BAP1) is a potent tumour suppressor gene that modulates environmental carcinogenesis. All carriers of inherited heterozygous germline BAP1-inactivating mutations (BAP1+/-) developed one and often several BAP1-/- malignancies in their lifetime, mostly malignant mesothelioma, uveal melanoma, and so on. Moreover, BAP1-acquired biallelic mutations are frequent in human cancers. BAP1 tumour suppressor activity has been attributed to its nuclear localization, where it helps to maintain genome integrity. The possible activity of BAP1 in the cytoplasm is unknown. Cells with reduced levels of BAP1 exhibit chromosomal abnormalities and decreased DNA repair by homologous recombination, indicating that BAP1 dosage is critical. Cells with extensive DNA damage should die and not grow into malignancies. Here we discover that BAP1 localizes at the endoplasmic reticulum. Here, it binds, deubiquitylates, and stabilizes type 3 inositol-1,4,5-trisphosphate receptor (IP3R3), modulating calcium (Ca2+) release from the endoplasmic reticulum into the cytosol and mitochondria, promoting apoptosis. Reduced levels of BAP1 in BAP1+/- carriers cause reduction both of IP3R3 levels and of Ca2+ flux, preventing BAP1+/- cells that accumulate DNA damage from executing apoptosis. A higher fraction of cells exposed to either ionizing or ultraviolet radiation, or to asbestos, survive genotoxic stress, resulting in a higher rate of cellular transformation. We propose that the high incidence of cancers in BAP1+/- carriers results from the combined reduced nuclear and cytoplasmic activities of BAP1. Our data provide a mechanistic rationale for the powerful ability of BAP1 to regulate gene-environment interaction in human carcinogenesis.


Assuntos
Cálcio/metabolismo , Transformação Celular Neoplásica , Citoplasma/metabolismo , Retículo Endoplasmático/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Mitocôndrias/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina Tiolesterase/metabolismo , Apoptose/genética , Amianto/toxicidade , Sinalização do Cálcio , Núcleo Celular/metabolismo , Sobrevivência Celular , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos da radiação , Células Cultivadas , Dano ao DNA , Epitélio , Fibroblastos , Interação Gene-Ambiente , Humanos , Ligação Proteica , Estabilidade Proteica , Proteínas Supressoras de Tumor/deficiência , Proteínas Supressoras de Tumor/genética , Ubiquitina/metabolismo , Ubiquitina Tiolesterase/deficiência , Ubiquitina Tiolesterase/genética
9.
Clin Psychol Psychother ; 30(2): 250-269, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36404411

RESUMO

BACKGROUND: Compassion-focused imagery (CFI) is a technique used to facilitate self-compassion by constructing and exploring imagery of a compassionate ideal. It is commonly used in Compassionate Mind Training, as part of a wider skills training intervention. This review aimed to explore the effectiveness of CFI on psychological outcomes when used as a brief standalone intervention across clinical and non-clinical adult populations. Population-specific effects were also explored. METHODS: Following an extensive literature search, 20 studies were identified for inclusion in the review. Quality and risk of bias assessment were completed using the Effective Public Health Practice Project (EPHPP) tool. Where available, effect sizes were calculated for outcome measures of self-compassion, self-criticism and shame. Study findings were qualitatively synthesized. RESULTS: Most of the studies reported improvements in psychological outcomes, such as improvements in self-compassion and positive affect, reduction in self-criticism, shame and paranoia. Across measures of self-compassion, self-criticism and shame, the effect sizes ranged between 0.02 and 1.1 and estimated treatment effects range between 0.09 and 1.39. Preliminary evidence is promising, with most studies reporting improvements in psychological outcomes; however, the evidence is limited by the methodological challenges and heterogeneity within the literature. Studies that implemented CFI in severe head injury samples reported limited improvements. Improvements in paranoia measures were more consistently reported in non-clinical samples, when compared to studies using clinical samples. High levels of self-criticism emerged as an important potential barrier in individuals' ability to engage with CFI tasks.


Assuntos
Empatia , Vergonha , Adulto , Humanos , Autoavaliação (Psicologia) , Avaliação de Resultados em Cuidados de Saúde , Transtornos Paranoides
10.
J Ment Health ; 32(4): 787-804, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36151719

RESUMO

BACKGROUND: There is increasing interest in the association between nature, health and wellbeing. Gardening is a popular way in which interaction with nature occurs and numerous gardening projects aim to facilitate wellbeing among participants. More research is needed to determine their effectiveness. AIM: To systematically evaluate the effectiveness of group-based gardening interventions for increasing wellbeing and reducing symptoms of mental ill-health in adults. METHODS: A systematic review of Randomised Controlled Trials was conducted following the protocol submitted to PROSPERO (CRD42020162187). Studies reporting quantitative validated health and wellbeing outcomes of the community residing, adult populations (18+) were eligible for inclusion. RESULTS: 24 studies met inclusion criteria: 20 completed and four ongoing trials. Meta-analyses suggest these interventions may increase wellbeing and may reduce symptoms of depression, however, there was uncertainty in the pooled effects due to heterogeneity and unclear risk of bias for many studies. There were mixed results for other outcomes. RESEARCH LIMITATIONS/IMPLICATIONS: Heterogeneity and small sample sizes limited the results. Poor reporting precluded meta-analysis for some studies. Initial findings for wellbeing and depression are promising and should be corroborated in further studies. The research area is active, and the results of the ongoing trials identified will add to the evidence base.


Assuntos
Jardinagem , Saúde Mental , Adulto , Humanos
11.
Neuropsychol Rehabil ; 32(1): 84-103, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32715913

RESUMO

Traumatic events can be associated with positive change, termed "post-traumatic growth." Existing resesarch suggests some overlap between post-traumatic growth and value-directed living. This study sought to explore the relationship between post-traumatic growth and value-directed living after acquired brain injury. Self-report questionnaires including the Posttraumatic Growth Inventory, Valued Living Questionnaire, Engaged Living Scale, Valuing Questionnaire, Hospital Anxiety and Depression Scale, World Health Organization Well-Being Index, Brief Resilience Scale, Trauma Screening Questionnaire and Glasgow Outcome Scale were posted to 317 individuals who had experienced a head injury, stroke or subarachnoid haemorrhage in the previous 3-13 years, with a hospital admission of minimum 7 days. Questionnaires were completed by 81 participants. Post-traumatic growth was significantly positively associated with two measures of value-directed living (VLQ, r = .269; VQ, r = .215). Higher levels of value-directed living were significantly associated with increased positive outcomes (wellbeing) and reduced negative outcomes (distress, post-traumatic stress symptoms). There was no significant association between post-traumatic growth and any of these outcomes. The association between post-traumatic growth and value-directed living indicates possible common underlying processes. Value-directed living appears to be a more useful concept, as it was associated with clinically relevant outcomes. It is recommended that value-directed living interventions are considered in brain injury rehabilitation.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , Crescimento Psicológico Pós-Traumático , Lesões Encefálicas/complicações , Lesões Encefálicas Traumáticas/complicações , Humanos , Inquéritos e Questionários
12.
Clin Psychol Psychother ; 29(2): 579-589, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34260130

RESUMO

Measurement of adverse effects of psychological therapy is inconsistent due to ambiguity about the concept. The perspective of people undertaking psychological therapy (that is, experts by experience) has largely been overlooked. This study will investigate whether there is consensus between the opinions of professionals and experts by experience. The Delphi method was used. In Round 1 thematic analysis was used to analyse qualitative responses. Wilcoxon rank-sum tests were used to examine group differences in Rounds 2 and 3. The study protocol was prospectively registered, reference osf.io/f9wp7. Fifty-one professionals and 51 experts by experience generated 147 potential adverse effects in Round 1, across 9 themes; including 'therapy amplifies problem', 'emotional lability' and 'sense of self'. Each item was rated for overall consensus in Rounds 2 (n = 62) and 3 (n = 63). Thirty-eight items were rated as essential, very important or important to include on a list of potential adverse effects. A further 12 items were rated as important by the expert by experience group only. Professionals were more conservative in their ratings. There appeared to be consensus between professionals and experts by experience on what to include in a list of adverse effects of psychological therapy (the EDAPT), including novel adverse effects which have not been previously considered. Further research is required to understand which adverse effects are necessary, unnecessary, or indeed harmful to psychotherapy outcomes.


Assuntos
Consenso , Técnica Delphi , Humanos
13.
New Phytol ; 232(4): 1591-1602, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34018616

RESUMO

Mangroves are among the world's most carbon-dense ecosystems, but have suffered extensive deforestation, prompting reforestation projects. The effects of mangrove reforestation on belowground carbon dynamics are poorly understood. In particular, we do not know how fine root production develops following mangrove reforestation, despite fine root production being a major carbon sink and an important control of mangrove soil accretion. Using minirhizotrons, we investigated fine root production and its depth variation along a chronosequence of mature Vietnamese mangroves. Our results showed that fine root production decreases strongly with stand age in the uppermost 32 cm of our soil profiles. In younger mangrove stands, fine root production declines with depth, possibly due to a vertical gradient in soil nutrient availability; while root production in the oldest stand is low at all depths and exhibits no clear vertical pattern. A major fraction of fine root production occurs deeper than 30 cm, depths that are commonly omitted from calculations of mangrove carbon budgets. Younger mangroves may accrue shallow soil organic matter faster than older mangroves. Therefore, root productivity and forest stand age should be accounted for when forecasting mangrove carbon budgets and resistance to sea-level rise.


Assuntos
Ecossistema , Áreas Alagadas , Carbono , Sequestro de Carbono , Florestas , Solo
14.
Phys Rev Lett ; 126(9): 095101, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33750160

RESUMO

Collisionless shocks are ubiquitous in the Universe and often associated with a strong magnetic field. Here, we use large-scale particle-in-cell simulations of nonrelativistic perpendicular shocks in the high-Mach-number regime to study the amplification of the magnetic field within shocks. The magnetic field is amplified at the shock transition due to the ion-ion two-stream Weibel instability. The normalized magnetic field strength strongly correlates with the Alfvénic Mach number. Mock spacecraft measurements derived from particle-in-cell simulations are fully consistent with those taken in situ at Saturn's bow shock by the Cassini spacecraft.

15.
Proc Natl Acad Sci U S A ; 115(19): 4851-4856, 2018 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-29666256

RESUMO

Widespread establishment of peatlands since the Last Glacial Maximum represents the activation of a globally important carbon sink, but the drivers of peat initiation are unclear. The role of climate in peat initiation is particularly poorly understood. We used a general circulation model to simulate local changes in climate during the initiation of 1,097 peatlands around the world. We find that peat initiation in deglaciated landscapes in both hemispheres was driven primarily by warming growing seasons, likely through enhanced plant productivity, rather than by any increase in effective precipitation. In Western Siberia, which remained ice-free throughout the last glacial period, the initiation of the world's largest peatland complex was globally unique in that it was triggered by an increase in effective precipitation that inhibited soil respiration and allowed wetland plant communities to establish. Peat initiation in the tropics was only weakly related to climate change, and appears to have been driven primarily by nonclimatic mechanisms such as waterlogging due to tectonic subsidence. Our findings shed light on the genesis and Holocene climate space of one of the world's most carbon-dense ecosystem types, with implications for understanding trajectories of ecological change under changing future climates.


Assuntos
Carbono/metabolismo , Aquecimento Global , Modelos Biológicos , Solo , Áreas Alagadas
16.
Infancy ; 26(3): 352-368, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33645890

RESUMO

Physiological adaptations to external stressors can reveal socio-cognitive health in infancy. With the use of thermal imaging and behavioural analyses, the current study examined the arousal markers accompanying infants' interactions with a familiar and an unfamiliar person. To address the current research question, the mother and a complete stranger interacted with 2 to 3 month-old infants (N= 10, 2 boys)in three different conditions: Neutral, Play, and Compliment. Behavioral analyses showed that overall gaze was longer to the Stranger compared to the Mother independent of condition. Physiological findings showed that skin temperature was significantly higher with the stranger independent of condition. The regions of the face that passed the significance threshold included the maxillary area, the nose, and the forehead. Both behavioral and physiological findings emphasize the ability of the infant to distinguish between a familiar and an unfamiliar person. Most importantly, however thermal imaging has proven to be a promising tool in physiologically differentiating between variable social conditions in very young infants opening up a new experimental portal for identifying healthy physiological development.


Assuntos
Mães , Interação Social , Nível de Alerta , Feminino , Humanos , Lactente , Masculino
17.
Mol Plant Microbe Interact ; 33(5): 727-741, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32096689

RESUMO

In bacteria, FtsZ proteins form a Z ring that is the initial step preceding septal fission. FtsZ proteins enable the division of mitochondria in early eukaryotes and are present in some kingdoms but have been lost in animals, fungi, and plants. Here, we have identified two Phytophthora capsici ortholog genes of Escherichia coli FtsZs, designated PcFtsZ1 and PcFtsZ2. Overexpression of PcFtsZ2 in E. coli fully complemented the overexpression phenotype of EcFtsZ. In contrast, overexpression of PcFtsZ1 in E. coli had minimal impact on cell division and separation. Thus, we focused on evaluating the impact of altered expression of PcFtsZ2 in P. capsici, as it exhibited the strongest phenotype. PcFtsZ2 was expressed at the highest levels in mycelia, sporangia, and germinating cysts, as well as in late infection. PcFtsZ2 mis-expression lines showed aberrant asexual growth and development of P. capsici. Alterations in the expression of PcFtsZ2 changed the distribution of mitochondria in hyphae and sporangia and, also, affected the number, size, and shape of actin plaques. Silencing of PcFtsZ2 restrained growth and development of invasive structures, especially cysts and sporangia, substantially inhibiting the ability of transformants to cause blight lesions. In overexpressed transformant lines, cyst and sporangial germination rates were only half that of controls, but hyphal growth from direct germination of sporangia was more rapid than controls. These transformant lines were only slightly impaired in virulence relative to controls. This study emphasizes the essential role of the evolutionarily conserved FtsZ2 proteins in affecting cytoskeleton dynamics.


Assuntos
Phytophthora/genética , Doenças das Plantas/microbiologia , Animais , Escherichia coli , Phytophthora/crescimento & desenvolvimento , Phytophthora/patogenicidade , Plantas/microbiologia
18.
Glob Chang Biol ; 26(3): 1899-1907, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31750606

RESUMO

Mangroves are among the world's most carbon-dense ecosystems, but they are threatened by rapid climate change and rising sea levels. The accumulation and decomposition of soil organic matter (SOM) are closely tied to mangroves' carbon sink functions and resistance to rising sea levels. However, few studies have investigated the response of mangrove SOM dynamics to likely future environmental conditions. We quantified how mangrove SOM decay is affected by predicted global warming (+4°C), sea level changes (simulated by altering of the inundation duration to 0, 2, and 6 hr/day), and their interaction. Whilst changes in inundation duration between 2 and 6 hr/day did not affect SOM decay, the treatment without inundation led to a 60% increase. A warming of 4°C caused SOM decay to increase by 21%, but longer inundation moderated this temperature-driven increase. Our results indicate that (a) sea level rise is unlikely to decrease the SOM decay rate, suggesting that previous mangrove elevation gain, which has allowed mangroves to persist in areas of sea level rise, might result from changes in root production and/or mineral sedimentation; (b) sea level fall events, predicted to double in frequency and area, will cause periods of intensified SOM decay; (c) changing tidal regimes in mangroves due to sea level rise might attenuate increases in SOM decay caused by global warming. Our results have important implications for forecasting mangrove carbon dynamics and the persistence of mangroves and other coastal wetlands under future scenarios of climate change.


Assuntos
Ecossistema , Solo , Sequestro de Carbono , Mudança Climática , Áreas Alagadas
19.
J Surg Oncol ; 121(3): 511-517, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31907944

RESUMO

BACKGROUND AND METHODS: Complex en-bloc multivisceral and oncovascular resections for upper abdominal tumors remain rare, but there is increasing interest in their role. We analyze complications and survival for these operations. We performed a retrospective cohort study of patients who underwent en-bloc upper abdominal resections for tumors involving multiple organs. Primary outcomes were complications as per the Clavien-Dindo Classification and Comprehensive Complication Index (CCI). Secondary outcome was overall survival (OS). RESULTS: We identified 60 consecutive patients who underwent resection from 2011 to 2018. Histopathology was heterogeneous, the most common being renal cell carcinoma. Eighteen patients had major complications. Mean (interquartile range) CCI was 29.6 (9.6-43.9). Liver resection was significantly associated with an increased CCI and increased the odds of a major complication (odds ratio: 4.67, 95% confidence interval [CI]: 1.31-16.59; P = .017). Charlson Comorbidity Score was significantly associated with the presence of at least one major complication. Mean OS was 47.1 months (95% CI: 37.6-56.6). CONCLUSION: In appropriately selected patients, and when undertaken in centers with appropriate subspecialist surgical teams and intensive care services, en-bloc multivisceral resection of upper abdominal tumors is safe, but liver resection is associated with an increase in major complications.


Assuntos
Neoplasias Abdominais/cirurgia , Procedimentos Cirúrgicos de Citorredução/métodos , Fígado/cirurgia , Neoplasias Abdominais/diagnóstico por imagem , Neoplasias Abdominais/patologia , Idoso , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/cirurgia , Estudos de Coortes , Procedimentos Cirúrgicos de Citorredução/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos
20.
J Chem Inf Model ; 60(9): 4191-4199, 2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32568539

RESUMO

Cheminformatics aims to assist in chemistry applications that depend on molecular interactions, structural characteristics, and functional properties. The arrival of deep learning and the abundance of easily accessible chemical data from repositories like PubChem have enabled advancements in computer-aided drug discovery. Virtual high-throughput screening (vHTS) is one such technique that integrates chemical domain knowledge to perform in silico biomolecular simulations, but prediction of binding affinity is restricted due to limited availability of ground-truth binding assay results. Here, text representations of 83 000 000 molecules are leveraged to perform single-target binding affinity prediction directly on the outcome of screening assays. The embedding of an end-to-end transformer neural network, trained to encode the structural characteristics of a molecule via a text-based translation task, is repurposed through transfer learning to classify binding affinity to single targets with few known binding compounds. We quantify the observed increase in AUC on binding prediction tasks between classifiers trained on the translation embedding versus those using an untrained embedding. Visualization of the embedding space reveals organization of structural and functional properties that aid binding prediction. The pretrained transformer, data, and associated software to extract embeddings are made publicly available at https://github.com/mpcrlab/MolecularTransformerEmbeddings.


Assuntos
Redes Neurais de Computação , Software , Simulação por Computador , Descoberta de Drogas
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