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1.
J Craniomaxillofac Surg ; 52(2): 141-150, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38195297

RESUMO

Oral squamous cell carcinoma (OSCC) is the most prevalent type of head and neck cancer, and lymph node metastasis is a crucial prognostic factor that has a direct correlation with the survival rate. The standard procedure for managing clinically negative (cN0) neck in OSCC patients is elective neck dissection (END), but it can lead to various complications that affect the patient's quality of life. Therefore, medical professionals are exploring the use of the sentinel lymph node biopsy (SLNB) to manage cN0 neck in OSCC patients. The aim of this systematic review and meta-analysis was to compare the overall survival (OS) and disease-free survival (DFS) of patients undergoing SLNB and END in the surgical management of early cN0 neck in OSCC patients. To conduct this study, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was used to report the systematic reviews. The study included all comparative clinical studies, including randomized clinical trials (RCTs), clinical perspective studies, and retrospective studies that compared END to SLNB for early cN0 neck in OSCC patients. The hazard ratio (HR) and risk ratio (RR) with 95% confidence interval (CI) were calculated using comprehensive meta-analysis. The primary outcome variables were OS, DFS, and disease-specific survival (DSS). The secondary outcome variable was the nodal recurrence rate without local or distant metastasis. The GRADE system was used to assess the evidence's certainty. The meta-analysis included 12 clinical studies, comprising three RCTs and seven non-RCTs. The results showed no statistically significant difference between END and SLNB concerning OS (HR = 0.993, CI: 0.814 to 1.211, P = 0.947, low-quality evidence), DFS (HR = 0.705, CI: 0.408 to 1.29, P = 0.21, low-quality evidence), and nodal recurrence (RR = 1.028, CI: 0.969 to 1.090, P = 0.907, low-quality evidence). Additionally, SLNB was non-inferior to END regarding DSS (RR = 1.028, CI: 0.969 to 1.090, P = 0.907, low-quality evidence). In conclusion, this research affirms the safety and precision of SLNB as a means to stage cN0 OSCC patients, with outcomes that are comparable to END in terms of survival and nodal recurrence. Nevertheless, it's crucial to acknowledge that the quality of evidence in this study was relatively low. Therefore, additional RCTs comparing END to SLNB are warranted to validate these results and offer more robust guidance for managing cN0 OSCC patients.

2.
Eur J Vasc Endovasc Surg ; 66(4): 493-500, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37490978

RESUMO

OBJECTIVE: There is a paucity of observational data including long term outcomes after invasive treatment for carotid artery stenosis. METHODS: This retrospective study used nationwide insurance claims from the third largest provider in Germany, DAK-Gesundheit. Patients who underwent inpatient carotid endarterectomy (CEA) or carotid artery stenting (CAS) between 1 January 2008 and 31 May 2017 were included. The Elixhauser comorbidity scores from longitudinally linked hospital episodes were used. Kaplan-Meier analysis and the log rank test were used to determine long term stroke free survival. Multivariable regression models were developed to adjust for confounding. RESULTS: A total of 22 637 individual patients (41.6% female, median age 72.5 years) were included, of whom 15 005 (66.3%) were asymptomatic and 17 955 (79.3%) underwent CEA. After a median of 48 months, 5 504 any stroke or death events were registered. The mortality rate varied between 0.4% (CEA for asymptomatic stenosis) and 2.1% (urgent CAS for acute stroke patients) at 30 days, and between 4.1% and 8.4% at one year, respectively. The rate for any stroke varied between 0.6% (CEA for asymptomatic stenosis) and 2.5% (CAS for symptomatic patients) at 30 days, and between 2.5% and 6.4% at one year, respectively. The combined rate for any stroke and mortality at one year was 6.3% (CEA for asymptomatic stenosis), 8.7% (CAS for asymptomatic stenosis), and 12.5% (urgent CAS for acute stroke patients). After five years, the overall stroke rate was 7.4% after CEA and 9.0% after CAS. In adjusted analyses, both older age and van Walraven comorbidity score were associated with events, while treatment of asymptomatic stenosis was associated with lower event rates. CONCLUSION: The current study revealed striking differences between previous landmark trials and real world practice. It further suggested excess deaths among invasively treated asymptomatic patients.

3.
Oral Maxillofac Surg Clin North Am ; 35(1): 71-82, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36336597

RESUMO

We have observed a revival of the original Surgery First approach in orthognathic surgery. Fully digital planning and simulation of the surgery has improved the predictability of Surgery First procedures. The orthodontist plays a crucial role in the successful management of Surgery First and Surgery Early cases. Surgery First and Surgery Early procedures have made the correction of a dentofacial deformity and dysgnathia a clear and transparent procedure. The decision of the treatment protocol is based on a thorough consideration and discussion between the surgeon, the orthodontist, and the patient for a successful outcome.


Assuntos
Deformidades Dentofaciais , Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Humanos , Procedimentos Cirúrgicos Ortognáticos/métodos , Deformidades Dentofaciais/cirurgia
4.
J Plant Physiol ; 271: 153643, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35248933

RESUMO

Cucurbits have been used as phloem research models for many decades because their exudates can be accessed with ease. However, cucurbit plants possess two distinct phloem systems known as the fascicular phloem (FP) and extrafascicular phloem (EFP). Therefore, the molecular composition and function of certain exudates can be misinterpreted due to their unclear origin. To characterize the anatomy and function of the different phloem systems more clearly, we generated specific antibodies against marker proteins (PP1 homologs) allowing the clear identification of the EFP at the organ, tissue and cellular levels by immunological staining. We also used detailed microscopy to determine common and unique anatomical features of the FP and EFP sieve elements (SEs) in cucumber (Cucumis sativus). The comparison of exudation rates and the dynamic viscosity, density and sugar content of the exudates from plants grown in the light and dark revealed the consistent composition and behavior of the EFP exudate even when photosynthesis was prevented, thus differing from the properties of the FP exudate. Furthermore, the analysis of phloem transport using a fluorescein disodium salt showed only wound-induced exudation of dye from the EFP, indicating the absence of transport in this tissue. Our results show that it is important to distinguish between the EFP and FP in cucurbits, particularly their differing behaviors in response to wounding.


Assuntos
Cucumis sativus , Cucurbita , Transporte Biológico , Cucumis sativus/metabolismo , Cucurbita/anatomia & histologia , Cucurbita/metabolismo , Floema/metabolismo , Fotossíntese
5.
Biology (Basel) ; 11(1)2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35053121

RESUMO

Acute myocardial infarction (AMI) is a result of cardiac non-perfusion and leads to cardiomyocyte necrosis, inflammation, and compromised cardiac performance. Here, we showed that the secretome of γ-irradiated peripheral blood mononuclear cells (PBMCsec) improved heart function in a porcine AMI model and displayed beneficial long- and short-term effects. As an AMI is known to strongly affect gene regulation of the ischemia non-affected heart muscle and distal organs, we employed a transcriptomics approach to further study the immediate molecular events orchestrated using the PBMCsec in myocardium, liver, and spleen 24 h post ischemia. In the infarcted area, the PBMCsec mainly induced genes that were essential for cardiomyocyte function and simultaneously downregulated pro-inflammatory genes. Interestingly, genes associated with pro-inflammatory processes were activated in the transition zone, while being downregulated in the remote zone. In the liver, we observed a pronounced inhibition of immune responses using the PBMCsec, while genes involved in urea and tricarboxylic cycles were induced. The spleen displayed elevated lipid metabolism and reduced immunological processes. Together, our study suggested several types of pharmacodynamics by which the PBMCsec conferred immediate cardioprotection. Furthermore, our data supported the assumption that an AMI significantly affects distal organs, suggesting that a holistic treatment of an AMI, as achieved by PBMCsec, might be highly beneficial.

6.
Cell Host Microbe ; 29(11): 1601-1603, 2021 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-34762824

RESUMO

Phytoplasmas are pathogenic bacteria that manipulate their plant hosts in dramatic ways. In issue 20 Vol. 184 of Cell, Huang and colleagues report on a phytoplasma effector protein that brings about manifold effects by a surprising mechanism. Are resistant plants on the horizon now?


Assuntos
Phytoplasma , Doenças das Plantas , Plantas
7.
PLoS Pathog ; 17(3): e1009459, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33765095

RESUMO

The host-pathogen combinations-Malus domestica (apple)/`Candidatus Phytoplasma mali´, Prunus persica (peach)/`Ca. P. prunorum´ and Pyrus communis (pear)/`Ca. P. pyri´ show different courses of diseases although the phytoplasma strains belong to the same 16SrX group. While infected apple trees can survive for decades, peach and pear trees die within weeks to few years. To this date, neither morphological nor physiological differences caused by phytoplasmas have been studied in these host plants. In this study, phytoplasma-induced morphological changes of the vascular system as well as physiological changes of the phloem sap and leaf phytohormones were analysed and compared with non-infected plants. Unlike peach and pear, infected apple trees showed substantial reductions in leaf and vascular area, affecting phloem mass flow. In contrast, in infected pear mass flow and physicochemical characteristics of phloem sap increased. Additionally, an increased callose deposition was detected in pear and peach leaves but not in apple trees in response to phytoplasma infection. The phytohormone levels in pear were not affected by an infection, while in apple and peach trees concentrations of defence- and stress-related phytohormones were increased. Compared with peach and pear trees, data from apple suggest that the long-lasting morphological adaptations in the vascular system, which likely cause reduced sap flow, triggers the ability of apple trees to survive phytoplasma infection. Some phytohormone-mediated defences might support the tolerance.


Assuntos
Produtos Agrícolas/microbiologia , Malus/imunologia , Doenças por Fitoplasmas/imunologia , Imunidade Vegetal/fisiologia , Prunus persica/imunologia , Produtos Agrícolas/imunologia , Malus/microbiologia , Phytoplasma/imunologia , Folhas de Planta/microbiologia , Feixe Vascular de Plantas/microbiologia , Prunus persica/microbiologia , RNA Ribossômico 16S
8.
Ann Transl Med ; 9(2): 117, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33569419

RESUMO

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality and is characterized by episodes of acute exacerbations. Finding a systemic biomarker that reliably predicts outcome after an acute exacerbation remains a major challenge. Heat shock protein 27 (HSP27) has been previously studied in COPD, however, urine excretion trajectory and prognostic value after an exacerbation is unknown. METHODS: In this retrospective post hoc analysis of a prospective study that included 253 COPD patients who were hospitalized for acute exacerbation, 207 patients were analyzed. Urine and serum were sampled at admission, discharge, and 180 days after discharge; urine excretion trajectory was analyzed and correlated with clinicopathological and survival data. RESULTS: HSP27 urine excretion increased after an exacerbation episode [1.8% admission, 1.8% discharge, 2.3% 180 days after discharge (P=0.091)]. In severely ill patients (GOLD IV) this course was even more distinct [1.6% admission, 2.1% discharge, 2.8% 180 days after discharge (P=0.007)]. Furthermore, fractional HSP27 urine excretion at discharge was increased in GOLD IV patients (P=0.031). In Kaplan-Meier and univariable Cox proportional hazard models patients with HSP27 urine excretion below 0.845% showed significantly worse survival at 30, 90 and 180 days after discharge. In a multivariable Cox proportional hazard model including established COPD outcome parameters fractional HSP27 urine excretion remained a significant predictor of survival at 30 and 90 days after discharge. Comparing this model to our already published model that includes HSP27 serum concentration we could show that fractional HSP27 urine excretion performs better in short-term survival. CONCLUSIONS: Our findings provide novel information about fractional HSP27 urine excretion trajectory in acute exacerbation of COPD. Fractional HSP27 urine excretion may be significantly reduced during an episode of acute exacerbation in COPD patients and may be used as a predictor of short-term all-cause mortality.

9.
Int J Mol Sci ; 22(2)2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33419062

RESUMO

Forisomes are giant fusiform protein complexes composed of sieve element occlusion (SEO) protein monomers, exclusively found in sieve elements (SEs) of legumes. Forisomes block the phloem mass flow by a Ca2+-induced conformational change (swelling and rounding). We studied the forisome reactivity in four different legume species-Medicago sativa, Pisum sativum, Trifolium pratense and Vicia faba. Depending on the species, we found direct relationships between SE diameter, forisome surface area and distance from the leaf tip, all indicative of a developmentally tuned regulation of SE diameter and forisome size. Heat-induced forisome dispersion occurred later with increasing distance from the stimulus site. T. pratense and V. faba dispersion occurred faster for forisomes with a smaller surface area. Near the stimulus site, electro potential waves (EPWs)-overlapping action (APs), and variation potentials (VPs)-were linked with high full-dispersion rates of forisomes. Distance-associated reduction of forisome reactivity was assigned to the disintegration of EPWs into APs, VPs and system potentials (SPs). Overall, APs and SPs alone were unable to induce forisome dispersion and only VPs above a critical threshold were capable of inducing forisome reactions.


Assuntos
Fabaceae/fisiologia , Proteínas de Plantas/metabolismo , Cálcio/metabolismo , Fenômenos Eletrofisiológicos , Fabaceae/crescimento & desenvolvimento , Fabaceae/metabolismo , Medicago sativa/crescimento & desenvolvimento , Medicago sativa/metabolismo , Pisum sativum/crescimento & desenvolvimento , Pisum sativum/metabolismo , Floema/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Especificidade da Espécie , Temperatura , Vicia faba/crescimento & desenvolvimento , Vicia faba/metabolismo
10.
Clin Chim Acta ; 510: 507-514, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32735982

RESUMO

BACKGROUND: The inflammatory markers sST2, HSP27 and hsCRP have already been identified as prognostic markers in chronic heart failure (HF). Though individual biomarkers have proven their value in mortality risk prediction, the role of a multimarker strategy needs further evaluation. MATERIALS AND METHODS: This is an exploratory reanalysis in chronic HF patients. Plasma HSP27, sST2 and hsCRP in outpatients with chronic HF were analysed. Patients were followed for a minimum of twelve months for the endpoint cardiovascular mortality and unplanned HF associated hospitalisation (=event). 15 year overall mortality was assessed retrospectively. The prognostic impact was assessed using a Cox proportional hazard model. RESULTS: 113 chronic HF patients were included. Median follow up time was 614 days and 37 patients (32.7%) experienced an event. A Kaplan-Meier analysis revealed that patients with increased sST2, HSP27 and hsCRP levels have significantly worse prognosis (p < 0.001). The use of a three-biomarker combination was superior in an independent risk prediction of an event (one high vs. two high: HR = 4.5, 95% CI: 1.3-15.5, p = 0.018; and one high vs. all high: HR = 9.8, 95% CI: 2.8-34.3, p < 0.001) as shown in a multivariable cox proportional hazard model. However, the biomarker panel did not predict 15 year overall mortality, in contrast to elevated HSP27 levels (p = 0.012). CONCLUSIONS: The combination of all three markers is an independent predictor of cardiovascular death and unplanned HF associated hospitalisation but not overall mortality. Our findings suggest that adding those markers in combination to well established risk assessment parameters may improve risk stratification.


Assuntos
Proteína C-Reativa , Insuficiência Cardíaca , Biomarcadores , Proteínas de Choque Térmico HSP27 , Insuficiência Cardíaca/diagnóstico , Proteínas de Choque Térmico , Humanos , Proteína 1 Semelhante a Receptor de Interleucina-1 , Chaperonas Moleculares , Prognóstico , Receptores Imunológicos , Estudos Retrospectivos
11.
Mol Ther Methods Clin Dev ; 18: 354-366, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32671138

RESUMO

Cardiosphere-derived cells (CDCs) are progenitor cells derived from heart tissue and have shown promising results in preclinical models. APOSEC, the secretome of irradiated peripheral blood mononuclear cells, has decreased infarct size in acute and chronic experimental myocardial infarction (MI). We enhanced the effect of CDCs with APOSEC preconditioning (apoCDC) and investigated the reparative effect in a translational pig model of reperfused MI. Supernatants of CDCs, assessed by proteomic analysis, revealed reduced production of extracellular matrix proteins after in vitro APOSEC preconditioning. In a porcine model of catheter-based reperfused anterior acute MI (AMI), CDCs with (apoCDC, n = 8) or without APOSEC preconditioning (CDC, n = 6) were infused intracoronary, 15 min after the start of reperfusion. Untreated AMI animals (n = 7) and sham procedures (n = 5) functioned as controls. 2-deoxy-2-(18 F)-fluoro-D-glucose-positron emission tomography-magnetic resonance imaging ([18F]FDG-PET-MRI), with late enhancement after 1 month, showed reduced scar volume and lower transmurality of the infarcted area in CDC and apoCDC compared to AMI controls. Segmental quantitative PET images displayed indicated more residual viability in apoCDC. The left-ventricle (LV) ejection fraction was improved nonsignificantly to 45.8% ± 8.6% for apoCDC and 43.5% ± 7.1% for CDCs compared to 38.5% ± 4.4% for untreated AMI. Quantitative hybrid [18F]FDG-PET-MRI demonstrated improved metabolic and functional recovery after CDC administration, whereas apoCDCs induced preservation of viability of the infarcted area.

12.
Toxins (Basel) ; 12(7)2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32645818

RESUMO

Pyrrolizidine alkaloids (PA) and PA N-oxides (PANO) are secondary plant metabolites exhibiting genotoxic and carcinogenic properties. Apart from the roots and leaves, PA/PANO are particularly present in pollen and nectar. Therefore, the spread of Jacobaea vulgaris in certain regions of northern Germany has an impact on the safety of honey produced in that region. In this study, raw honey samples (n = 437) were collected from usually three individual beehives per site (n = 73) in the district of Ostholstein and analyzed for 25 PA/PANO. The results reveal mean levels of 8.4, 1.5, and 72.6 µg/kg and maximum levels of 111, 59.4, and 3313 µg/kg, depending on the season (summer 2015 and spring/summer 2016, respectively). As far as individual data are concerned, sites near areas with J. vulgaris growth did not necessarily result in high PA/PANO values. Furthermore, intra-site investigations revealed remarkable differences in PA/PANO levels of raw honey collected by different bee colonies at the same site. Consumption of these regionally produced honeys entails an increased exposure to PA/PANO, especially in children and high consumers. Margin of exposure values of <10,000 and an exceedance of the health-based guidance value highlight that regionally produced and marketed honey must be considered with care for a proper risk assessment and risk management.


Assuntos
Asteraceae/metabolismo , Abelhas , Mel/análise , Óxidos/análise , Pólen/metabolismo , Alcaloides de Pirrolizidina/análise , Animais , Asteraceae/efeitos adversos , Qualidade de Produtos para o Consumidor , Alemanha , Pólen/efeitos adversos , Alcaloides de Pirrolizidina/efeitos adversos , Medição de Risco , Estações do Ano , Metabolismo Secundário , Fatores de Tempo
13.
Int J Mol Sci ; 21(13)2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32630157

RESUMO

Periodontal inflammation is associated with dying cells that potentially release metabolites helping to promote inflammatory resolution. We had shown earlier that the secretome of irradiated, dying peripheral blood mononuclear cells support in vitro angiogenesis. However, the ability of the secretome to promote inflammatory resolution remains unknown. Here, we determined the expression changes of inflammatory cytokines in murine bone marrow macrophages, RAW264.7 cells, and gingival fibroblasts exposed to the secretome obtained from γ-irradiated peripheral blood mononuclear cells in vitro by RT-PCR and immunoassays. Nuclear translocation of p65 was detected by immunofluorescence staining. Phosphorylation of p65 and degradation of IκB was determined by Western blot. The secretome of irradiated peripheral blood mononuclear cells significantly decreased the expression of IL1 and IL6 in primary macrophages and RAW264.7 cells when exposed to LPS or saliva, and of IL1, IL6, and IL8 in gingival fibroblasts when exposed to IL-1ß and TNFα. These changes were associated with decreased phosphorylation and nuclear translocation of p65 but not degradation of IκB in macrophages. We also show that the lipid fraction of the secretome lowered the inflammatory response of macrophages exposed to the inflammatory cues. These results demonstrate that the secretome of irradiated peripheral blood mononuclear cells can lower an in vitro simulated inflammatory response, supporting the overall concept that the secretome of dying cells promotes inflammatory resolution.


Assuntos
Fibroblastos/metabolismo , Inflamação/metabolismo , Leucócitos Mononucleares/metabolismo , Metabolismo dos Lipídeos , Lipídeos/fisiologia , Animais , Camundongos , Camundongos Endogâmicos BALB C , Células RAW 264.7
14.
J Craniomaxillofac Surg ; 48(5): 521-526, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32303420

RESUMO

Oral and maxillofacial surgery is correlated with a high risk of SARS-CoV-2 transmission. Therefore, the aim of the review is to collect and discuss aspects of the management of patients in oral and maxillofacial surgery during the COVID-19 pandemic. In order to save resources and to avoid unnecessary exposure to infected patients, there is the need to schedule interventions depending on their priority. During the peak of the pandemic, no elective surgery should be performed. Even urgent procedures might be postponed if there is a view to recovery of a COVID-19 patient within a few days. Emergency procedures do not allow any delay. Specialties with overlap in therapies should have well defined arrangements among each other concerning the treatment spectra in order to avoid redundancy and loss of resources. Inpatient and outpatient units have to be organized in such a way that the risk of cross-infection among patients is reduced to a minimum. Especially, testing of patients for SARS-CoV-2 is important to detect the infected patients at an early stage. When surgery is performed on COVID-19 patients, adequate personal protective equipment is crucial. There must be negative pressure in the operating room, and aerosol formation must be reduced to a minimum. In order to address the COVID-19 challenge adequately, significant changes in the infrastructure of outpatient units, inpatient units, and operating rooms are needed. In addition, the demands concerning personal protective equipment increase significantly. The major aim is to protect patients as well as the medical staff from unnecessary infection, and to keep the healthcare system running effectively. Therefore, every effort should be taken to make the necessary investments.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Controle de Infecções/métodos , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Pandemias , Equipamento de Proteção Individual , Pneumonia Viral , Cirurgia Bucal , Aerossóis , COVID-19 , Teste para COVID-19 , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Procedimentos Cirúrgicos Eletivos , Humanos , Pandemias/prevenção & controle , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , SARS-CoV-2 , Cirurgia Bucal/métodos
15.
Commun Biol ; 3(1): 108, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32144394

RESUMO

Lakes and reservoirs contribute substantially to atmospheric concentrations of the potent greenhouse gas methane. Lake sediments produce large amounts of methane, which accumulate in the oxygen-depleted bottom waters of stratified lakes. Climate change and eutrophication may increase the number of lakes with methane storage in the future. Whether stored methane escapes to the atmosphere during annual lake overturn is a matter of controversy and depends critically on the response of the methanotroph assemblage. Here we show, by combining 16S rRNA gene and pmoA mRNA amplicon sequencing, qPCR, CARD-FISH and potential methane-oxidation rate measurements, that the methanotroph assemblage in a mixing lake underwent both a substantial bloom and ecological succession. As a result, methane oxidation kept pace with the methane supplied from methane-rich bottom water and most methane was oxidized. This aspect of freshwater methanotroph ecology represents an effective mechanism limiting methane transfer from lakes to the atmosphere.


Assuntos
Bactérias/metabolismo , Efeito Estufa , Gases de Efeito Estufa/metabolismo , Metano/metabolismo , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Monitoramento Ambiental , Hibridização in Situ Fluorescente , Lagos/microbiologia , Oxirredução , Oxigenases/genética , Oxigenases/metabolismo , Dinâmica Populacional , Ribotipagem , Estações do Ano , Análise de Sequência de RNA , Fatores de Tempo , Microbiologia da Água
16.
Cell Stress Chaperones ; 25(1): 141-149, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31820266

RESUMO

Episodes of acute exacerbations are major drivers of hospitalisation and death from COPD. To date, there are no objective biomarkers of disease activity or biomarkers to predict patient outcome. In this study, 211 patients hospitalised for an acute exacerbation of COPD have been included. At the time of admission, routine blood tests have been performed including complete blood count, C-reactive protein, cardiac troponin T and NT-proBNP. Heat shock protein 27 (HSP27) serum concentrations were determined at time of admission, discharge and 180 days after discharge by ELISA. We were able to demonstrate significantly increased HSP27 serum concentrations in COPD patients at time of admission to hospital as compared to HSP27 concentrations obtained 180 days after discharge. In univariable Cox regression analyses, a HSP27 serum concentration ≥ 3098 pg/mL determined at admission was a predictor of all-cause mortality at 90 days, 180 days, 1 year and 3 years. In multivariable analyses, an increased HSP27 serum concentration at admission retained its prognostic ability with respect to all-cause mortality for up to 1-year follow-up. However, an increased HSP27 serum concentration at admission was not an independent predictor of long-term all-cause mortality at 3 years. Elevated serum HSP27 concentrations significantly predicted short-term mortality in patients admitted to hospital with acute exacerbation of COPD and could help to improve outcomes by identifying high-risk patients.


Assuntos
Proteína C-Reativa/metabolismo , Proteínas de Choque Térmico HSP27/metabolismo , Valor Preditivo dos Testes , Doença Pulmonar Obstrutiva Crônica/metabolismo , Biomarcadores/sangue , Feminino , Hospitalização/estatística & dados numéricos , Hospitais/estatística & dados numéricos , Humanos , Masculino , Prognóstico , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/diagnóstico
17.
ISME J ; 14(1): 274-287, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31624343

RESUMO

Lakes are a significant source of atmospheric methane, although methane-oxidizing bacteria consume most methane diffusing upward from anoxic sediments. Diverse methane-oxidizing bacteria form an effective methane filter in the water column of stratified lakes, yet, niche partitioning of different methane-oxidizing bacteria along the oxygen-methane counter gradient remains poorly understood. In our study, we reveal vertical distribution patterns of active methane-oxidizing bacteria along the oxygen-methane counter gradient of four lakes, based on amplicon sequencing analysis of 16S rRNA and pmoA genes, and 16S rRNA and pmoA transcripts, and potential methane oxidation rates. Differential distribution patterns indicated that ecologically different methane-oxidizing bacteria occupied the methane-deficient and oxygen-deficient part above and below the oxygen-methane interface. The interface sometimes harbored additional taxa. Within the dominant Methylococcales, an uncultivated taxon (CABC2E06) occurred mainly under methane-deficient conditions, whereas Crenothrix-related taxa preferred oxygen-deficient conditions. Candidatus Methylomirabilis limnetica (NC10 phylum) abundantly populated the oxygen-deficient part in two of four lakes. We reason that the methane filter in lakes is structured and that methane-oxidizing bacteria may rely on niche-specific adaptations for methane oxidation along the oxygen-methane counter gradient. Niche partitioning of methane-oxidizing bacteria might support greater overall resource consumption, contributing to the high effectivity of the lacustrine methane filter.


Assuntos
Lagos/microbiologia , Metano/metabolismo , Methylococcaceae/isolamento & purificação , Ecossistema , Gammaproteobacteria/isolamento & purificação , Lagos/química , Metano/análise , Methylococcaceae/genética , Methylococcaceae/metabolismo , Oxirredução , Oxigênio/análise , Filogenia , RNA Ribossômico 16S/genética
18.
J Colloid Interface Sci ; 560: 369-378, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31635882

RESUMO

The understanding and design of wetting-transport and wetting-charge-transport interplay in nanometer-sized pores is a still not fully understood key step in improving nanopore transport-related applications. A control of mesopore wettability accompanied by pore filling and ionic mesopore accessibility analysis is expected to deliver major insights into this interplay of nanoscale pore wetting and transport. For a systematic understanding, we demonstrate a gradual adjustment of nanopore ionic accessibility by gradually tuning silica nanopore wettability using chemical vapor phase deposition of 1H,1H,2H,2H-perfluorooctyl dimethylchlorosilane. The mutual influence of wetting on liquid imbibition, condensation, and molecular transport as well as on heat transfer were studied by ellipsometry, cyclic voltammetry and boiling experiments, respectively. A multi-methodical analytic approach was used to directly couple wetting properties of mesoporous silica thin films to ionic mesopore accessibility allowing us to determine two different ion transport mechanisms based on three defined wetting regimes as well as a threshold hydrophobicity suppressing pore accessibility. Furthermore, boiling experiments showed a clear increase in nucleation site density upon changing the wettability of the mesoporous surfaces from hydrophilic to hydrophobic. Hence, these results provide insights into the complex interplay of pore wall functionalization, wetting, and charge-dependent nanopore properties.

20.
Methods Mol Biol ; 2014: 439-447, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31197815

RESUMO

Electropotential waves (EPW) are involved in plant responses to both abiotic and biotic stresses. Three different types of EPWs have been identified: action potential, variation potential, and system potential, all of which have been indicated to participate in phloem-based communication between plant organs. In this chapter we describe in detail how to measure EPWs in plants, including how to access the phloem, and how to insert microelectrodes. Such experiments can be used, for example, to study the local and systemic signaling in response to diverse stimuli like microbial threat or herbivore attack.


Assuntos
Fenômenos Eletrofisiológicos , Microeletrodos , Floema/fisiologia , Fenômenos Fisiológicos Vegetais , Proteínas de Plantas/metabolismo , Transdução de Sinais
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