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1.
Langmuir ; 40(11): 5606-5616, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38501265

RESUMO

The motion of partly gold (Au)-coated Janus particles under laser irradiation is caused by self-thermophoresis. Despite numerous studies addressing this topic, the impact of the preparation method and the degree of coverage of the particle with Au on the resulting thermophoretic velocity has not yet been fully understood. A detailed understanding of the most important tuning parameters during the preparation process is crucial to design Janus particles that are optimized for Au coverage to receive a high thermophoretic velocity. In this study, we explore the influence of the fabrication process, which changes the Au cap size, on the resulting self-propulsion behavior of partly Au-coated polystyrene particles (Au-PS). Additionally, the impact of an underlying adhesion chromium layer is investigated. In addition to the most commonly used qualitative SEM and EDX measurements, we propose a novel and fast technique utilizing AFM studies to quantify the cap size. This non-invasive technique can be used to determine both the size and the maximum thickness of the Au cap. The Au cap size was systematically varied in a range between about 36 and 74% by different preparation strategies. Nevertheless, we showed that the differing Au cap sizes of the Janus particles in this range have no obvious effect on the thermophoretic velocity. This is a surprising result since one would expect an effect of the Au cap size due to different solvent flows around the Janus particles and is attributed to an additional torque near the surface of the measuring cell.

3.
Endosc Int Open ; 12(1): E78-E89, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38205218

RESUMO

Background and study aims There is still a lack of evidence-based recommendations concerning endoscopic bougienage in benign esophageal strictures. Our study aimed to assess the relevance of the time interval between endoscopic dilation (ED) sessions with regard to endoscopic and clinical response. Patients and methods We performed a retrospective study including patients treated with endoscopic bougienage for a benign esophageal stricture in two German centers. Primary endpoint was the number of ED until freedom from dysphagia was achieved. Secondary endpoints were analyses on reaching a diameter of 15 mm and on achieving clinical freedom from symptoms. Results Between April 2014 and March 2020, bougienage was used as the primary treatment for benign esophageal strictures in 238 patients (194 patients in Center 1; 44 patients in Center 2). Both centers differed in their endoscopic bougienage regime: Center 1 was characterized by a higher frequency of interventions compared to Center 2 (median: 2 days [range 1-28] vs. 10 days [range 1-41]; P <0.001). Clinical response was achieved significantly earlier using the high-frequency regimen in all patients except for those with post-radiogen strictures, who clinically benefited from a low-frequency ED program. Accordingly, patients receiving higher-frequency ED reached a significantly larger post-dilation diameter and considerably larger diameter differences. Conclusions The results of our study demonstrate that a treatment concept consisting of higher-frequency bougienages seems to be more effective in treating most types of esophageal stricture. Radiogenic strictures were the only types of stenoses that benefited from a lower frequency ED program.

4.
J Clin Med ; 12(22)2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-38002661

RESUMO

INTRODUCTION: Standardization of diagnostic criteria of autoimmune hepatitis (AIH) and primary biliary cholangitis (PBC) variant syndrome (AIH-PBC VS) has not been achieved so far and evidence-based recommendations for monitoring and treatment of the disease are still lacking. Our study aimed to assess the prevalence, biochemical, and serological features, as well as the clinical course, of VS. METHODS: We performed a retrospective study including all patients with VS between 1999 and 2020 in four German centers. Data on demographic parameters, biochemical and serological tests, treatment, and outcome were collected. RESULTS: Of 90 patients (3.1%) meeting Paris criteria for VS diagnosis, 65.6% showed AIH and PBC histological features, while biochemical Paris criteria were observed comparatively rarely. Further antibodies, which were not part of the diagnostic criteria of VS, were found in a subgroup of patients with available data (ACA: 30.0%; anti-CENP-A: 25.0%; anti-CENP-B: 33.3%; anti-SP100: 21.4%). Biochemical response was more frequently observed in patients treated with a combined therapy of ursodeoxycholic acid (UDCA) and immunosuppression (IS). Liver cirrhosis was detected in 31 patients (34.4%) and 25 patients (27.8%) developed clinical manifestations of portal hypertension. CONCLUSIONS: Biochemical Paris criteria of VS were rarely detected, thus implying that these cut-off values should be redefined. Regarding pharmacological treatment, combined therapy of UDCA and IS appeared to be more effective than monotherapy with UDCA.

5.
Surg Endosc ; 37(10): 7803-7811, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37605011

RESUMO

INTRODUCTION: Radiofrequency ablation (RFA) and hybrid argon plasma coagulation (H-APC) are established thermal ablation techniques for eradicating Barrett's esophagus after endoscopic resection. This study aimed to compare RFA with H-APC in relation to safety, effectiveness and eradication rates. METHODS: After endoscopic resection, patients were randomly assigned to H-APC or RFA. A simplified H-APC technique was applied at 60 W. RFA was used with a 90° focal catheter and a simplified protocol of 12 J/cm2 × 3 or with a Halo 360° balloon and 10 J/cm2/cleaning/10 J/cm2. Eradication rates and adverse events were recorded. Patients received follow-up examinations after 3, 6, 12 and 24 months. RESULTS: One hundred and one patients were finally included in the study (RFA N = 47, H-APC N = 54). The median follow-up period for short-term was 6.0 (CI 5.4-6.9) months and for long term 21 (CI 19.2.5-22.7) months. In total 211 ablations were performed. The eradication rates after long-term follow-up were 74.2% in the RFA group and 82.9% in the H-APC group. Post-interventional pain was significantly greater in the RFA group, with a mean score of 4.56/10 and duration of 7.54 days, in comparison with a mean score of 2.07/10 over 3.59 days in the H-APC group. Stenoses requiring intervention were noted in 3.7% of patients in the H-APC arm and 14.9% of those in the RFA arm. CONCLUSIONS: Both ablation techniques have good results in relation to the eradication rate, with a slightly better outcome in the H-APC group. The severity and duration of pain were significantly greater in the RFA group.


Assuntos
Esôfago de Barrett , Ablação por Cateter , Ablação por Radiofrequência , Humanos , Esôfago de Barrett/terapia , Coagulação com Plasma de Argônio , Estudos Prospectivos , Resultado do Tratamento , Ablação por Radiofrequência/efeitos adversos , Ablação por Cateter/métodos , Esofagoscopia/métodos
6.
J Clin Med ; 12(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37445409

RESUMO

We performed a retrospective single-center analysis to investigate the diagnostic yield of bone marrow puncture in patients with liver cirrhosis and cytopenia. Liver cirrhosis patients receiving bone marrow aspiration or biopsy for the diagnostic work-up of otherwise unexplained peripheral blood cytopenia at our institution between 2004 and 2020 were enrolled in this study. We evaluated findings from cytologic, histologic and immunologic assessment and final diagnostic outcomes. A total of 118 patients with a median age of 55 years and a median Child-Pugh score of B (8 points) were enrolled. The main etiologies of liver cirrhosis were viral hepatitis (B and C) or chronic alcohol consumption. The majority of patients (60%) exhibited concurrent anemia, leukocytopenia and thrombocytopenia. Bone marrow assessment revealed normal, unspecific or reactive alterations in 117 out of 118 patients (99%). One patient was diagnosed with myelodysplastic syndrome. Our findings suggest that peripheral blood cytopenia in patients with liver cirrhosis is rarely associated with a primary bone marrow pathology.

7.
J Clin Med ; 12(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37240598

RESUMO

BACKGROUND: Non-anastomotic biliary strictures (NAS) are a common cause of morbidity and mortality after liver transplantation. METHODS: All patients with NAS from 2008 to 2016 were retrospectively analyzed. The success rate and overall mortality of an ERCP-based stent program (EBSP) were the primary outcomes. RESULTS: A total of 40 (13.9%) patients with NAS were identified, of which 35 patients were further treated in an EBSP. Furthermore, 16 (46%) patients terminated EBSP successfully, and nine (26%) patients died during the program. All deaths were caused by cholangitis. Of those, one (11%) patient had an extrahepatic stricture, while the other eight patients had either intrahepatic (3, 33%) or combined extra- and intrahepatic strictures (5, 56%). Risk factors of overall mortality were age (p = 0.03), bilirubin (p < 0.0001), alanine transaminase (p = 0.006), and aspartate transaminase (p = 0.0003). The median duration of the stent program was 34 months (ITBL: 36 months; IBL: 10 months), and procedural complications were rare. CONCLUSIONS: EBSP is safe, but lengthy and successful in only about half the patients. Intrahepatic strictures were associated with an increased risk of cholangitis.

8.
J Clin Med ; 12(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37176604

RESUMO

BACKGROUND: Genesis and the prognostic value of olfactory dysfunction (OD) in COVID-19 remain partially described. The objective of our study was to characterize OD during SARS-CoV-2 infection and to examine whether testing of OD may be a useful tool in clinical practice in order to early identify patients with SARS-CoV-2 infection. METHODS: Olfactory function assessment was objectively carried out using the u-Smell-it® test. In a cross-sectional study part, we evaluated this test in a control cohort of SARS-CoV-2 negative tested patients, who attended the University Hospital Frankfurt between May 2021 and March 2022. In a second longitudinal study part, sensitivity and specificity of OD was evaluated as a diagnostic marker of a SARS-CoV-2 infection in Frankfurt am Main, Germany in SARS-CoV-2 infected patients and their close contacts. RESULTS: Among 494 SARS-CoV-2 negative tested patients, OD was detected in 45.7% and was found to be significantly associated with the male gender (p < 0.001), higher age (p < 0.001), cardiovascular and pulmonary comorbidities (p < 0.001; p = 0.03). Among 90 COVID-19 positive patients, OD was found in 65.6% and was significantly associated with male gender and positive smoking status (p = 0.04 each). Prevalence and severity of OD were significantly increased in infections with the Delta variant (B.1.617.2) compared to those with the Omicron variant (BA.1.1.529). Diagnostic sensitivity and specificity of OD for diagnosis of SARS-CoV-2 infection were 69% and 64%, respectively. CONCLUSION: OD is common in COVID-19 negative and positive tested patients with significantly different prevalence rates observed between different variants. Diagnostic accuracy of OD is not high enough to implement olfactory testing as a tool in diagnostic routine to early identify patients with a SARS-CoV-2 infection.

9.
J Clin Med ; 12(9)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37176616

RESUMO

BACKGROUND AND STUDY AIM: The incidence of wound infections after percutaneous endoscopic gastrostomy (PEG) varies widely in recent studies. The present study systematically investigates the underlying risk factors for the development of wound infections in a large cohort of patients over a long-term follow-up period. PATIENTS AND METHODS: A retrospective cohort study of patients undergoing PEG insertion using either the pull or push technique was conducted and patients followed up for 3 years. Tube-related wound infections were identified, and pathogens regularly cultured from wound swabs. Adjusted analysis was performed via univariate and multivariate logistic regression analysis. RESULTS: 616 patients were included in this study. A total of 25% percent of patients developed wound infections upon PEG tube insertion and 6.5% showed recurrent infections. Nicotine abuse (p = 0.01), previous ischemic stroke (p = 0.01) and head and neck cancer (p < 0.001) showed an increased risk for wound infection after PEG placement. Moreover, radio-chemotherapy was associated with the occurrence of wound infections (p < 0.001). Infection rates were similar between pull and push cohorts. The most common bacterial pathogen detected was Enterobacterales (19.2%). Staphylococcus aureus, Pseudomonas aeruginosa and enterococci were frequently detected in recurrent infection (14.2%, 11.4% and 9.6%, respectively). Antibiotic prophylaxis showed no effect on infection rates. CONCLUSIONS: Wound infections after PEG placement are common and occasionally occur as recurrent infections. There is potential for improvement in everyday clinical practice, particularly regarding antibiotic prophylaxis in accordance with guidelines.

10.
Sci Rep ; 13(1): 8290, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37217560

RESUMO

The electrical transport in bismuth nanowires is strongly influenced by both sample geometry and crystallinity. Compared to bulk bismuth, the electrical transport in nanowires is dominated by size effects and influenced by surface states, which gain increasing relevance with increasing surface-to-volume ratios, i.e. with decreasing wire diameter. Bismuth nanowires with tailored diameter and crystallinity constitute, therefore, excellent model systems, allowing to study the interplay of the different transport phenomena. Here, we present temperature-dependent Seebeck coefficient and relative electrical resistance measurements of parallel bismuth nanowire arrays with diameters between 40 and 400 nm synthesized by pulsed electroplating in polymer templates. Both electrical resistance and Seebeck coefficient exhibit a non-monotonic temperature dependence, with the sign of the Seebeck coefficient changing from negative to positive with decreasing temperature. The observed behavior is size-dependent and is attributed to limitations of the mean free path of the charge carriers within the nanowires. The observed size-dependent Seebeck coefficient and in particular the size-dependent sign change opens a promising avenue for single-material thermocouples with p- and n-legs made from nanowires with different diameters.

11.
RSC Adv ; 13(7): 4721-4728, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36760287

RESUMO

We report the catalytic performance of networks of highly interconnected Au nanowires with diameters tailored between 80 and 170 nm. The networks were synthesized by electrodeposition in etched ion-track polymer templates, and the synthesis conditions were developed for optimal wire crystallinity and network homogeneity. The nanowire networks were self-supporting and could be easily handled as electrodes in electrochemical cells or other devices. The electrochemically active surface area of the networks increased systematically with increasing the wire diameter. They showed a very stable performance during 200 CV cycles of methanol oxidation reactions, with the peak current density reaching up to 200 times higher than that of a flat reference electrode, with only a 5% drop in the peak current density. The Au nanowire networks proved to be excellent model systems for investigation of the performance of porous catalysts and very promising nanosystems for application in direct alcohol fuel cell catalysts.

13.
United European Gastroenterol J ; 9(4): 469-477, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33887119

RESUMO

BACKGROUND: Before performing endoscopy to remove prophylactic pancreatic stents placed in patients with high risk of post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP), X-ray imaging is recommended to confirm the stents position in the pancreatic duct. OBJECTIVES: The aim of the present study was to investigate the feasibility of prophylactic pancreatic stent detection by transabdominal ultrasonography, to reduce the burden of X-ray imaging, which is currently the golden standard. METHODS: All patients who received a pancreatic stent for PEP prophylaxis were included in the present prospective trial. First, stent position was determined by transabdominal ultrasonography. Afterwards, it was verified by X-ray imaging. Retained stents were removed by esophagogastroduodenoscopy. Dislocated stents needed no further intervention. RESULTS: Fourty-one patients were enrolled in this study. All prophylactic pancreatic stents were straight 6 cm long 5 Fr stents with external flap. All stents were removed between day 1 and 10 (median: 3 days) in all cases. In 34 of 41 cases (83.0%), the pancreatic stent was still in place on the day of examination. Twenty-nine of 34 (85.3%) stents were detected correctly by transabdominal ultrasonography. Overlying gas prevented visualization of the pancreas in 3/41 (7.3%) cases. Sensitivity of sonographic detection of the stent was 93.5% (29/31). Six of seven stents were determined correctly as dislocated by ultrasonography. Here, specificity was 85.7%. A positive predictive value of 96.7% (29/30) was examined. The negative predictive value was 75.0% (6/8). CONCLUSION: Transabdominal ultrasonography detects the majority of prophylactic pancreatic stents. Thereby, it helps to identify patients with an indication for endoscopy sufficiently. X-ray imaging could subsequently be omitted in about 70% of examinations, reducing the radiation exposure for the patient and the endoscopy staff.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Remoção de Dispositivo , Ductos Pancreáticos/diagnóstico por imagem , Ductos Pancreáticos/cirurgia , Pancreatite/prevenção & controle , Stents , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Estudos Prospectivos , Radiografia , Fatores de Risco , Sensibilidade e Especificidade , Ultrassonografia , Adulto Jovem
14.
Ann Vasc Surg ; 73: 417-422, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33383136

RESUMO

BACKGROUND: Endovascular aortic aneurysm repair (EVAR) has become the treatment of choice for most patients with abdominal aortic aneurysm (AAA). Open aneurysm repair (OAR) is still being used in a number of patients for specific reasons. The aim of the present study was to investigate the reasons and perioperative outcomes of OAR in a high-volume endovascular center. METHODS: All patients who underwent OAR in a single center institution during the period April 2010 to July 2019 were retrospectively analyzed. RESULTS: During the study period, 222 patients underwent OAR. One hundred and forty-one (63.5%) patients underwent elective surgery, and eighty-one (36.5%) patients were treated acutely. The reasons for the decision to perform OAR instead of EVAR were as follows: anatomical in 89 (40.1%) cases, rupture in unstable patient in 57 (25.7%) cases, AAA with concomitant iliac arterial occlusive disease in 44 (19.8%) cases, previous EVAR with complications in 14 (6.3%) cases, large pararenal aneurysm considered risky to wait for a customized fenestrated stent graft in 7 (3.2%) cases, young patient age in 4 (1.8%) cases, the patient's preference in 3 (1.4%) cases, infected/mycotic AAA in 2 (0.9%) cases, and simultaneous OAR with colon cancer resection (n = 1, 0.5%) and renal transplantation (n = 1, n = 0.5). Thirty-day mortality in elective cases was 5% (7/141) and in acute cases 34.6% (28/81). CONCLUSIONS: This study shows that OAR is still used for selected patients despite improvements in EVAR technology. The most common reason for OAR was an unsuitable anatomy for EVAR. Perioperative mortality of OAR both for acute and elective cases as observed in this study is in line with published outcomes of other centers.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/cirurgia , Procedimentos Cirúrgicos Vasculares , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/mortalidade , Aneurisma da Aorta Abdominal/fisiopatologia , Ruptura Aórtica/diagnóstico por imagem , Ruptura Aórtica/mortalidade , Ruptura Aórtica/fisiopatologia , Tomada de Decisão Clínica , Procedimentos Cirúrgicos Eletivos , Feminino , Alemanha , Hospitais com Alto Volume de Atendimentos , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Procedimentos Cirúrgicos Vasculares/mortalidade
15.
J Clin Monit Comput ; 35(5): 1085-1092, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-32734356

RESUMO

Standard monitoring of heart rate, blood pressure and arterial oxygen saturation during endoscopy is recommended by current guidelines on procedural sedation. A number of studies indicated a reduction of hypoxic (art. oxygenation < 90% for > 15 s) and severe hypoxic events (art. oxygenation < 85%) by additional use of capnography. Therefore, U.S. and the European guidelines comment that additional capnography monitoring can be considered in long or deep sedation. Integrated Pulmonary Index® (IPI) is an algorithm-based monitoring parameter that combines oxygenation measured by pulse oximetry (art. oxygenation, heart rate) and ventilation measured by capnography (respiratory rate, apnea > 10 s, partial pressure of end-tidal carbon dioxide [PetCO2]). The aim of this paper was to analyze the value of IPI as parameter to monitor the respiratory status in patients receiving propofol sedation during PEG-procedure. Patients reporting for PEG-placement under sedation were randomized 1:1 in either standard monitoring group (SM) or capnography monitoring group including IPI (IM). Heart rate, blood pressure and arterial oxygen saturation were monitored in SM. In IM additional monitoring was performed measuring PetCO2, respiratory rate and IPI. Capnography and IPI values were recorded for all patients but were only visible to the endoscopic team for the IM-group. IPI values range between 1 and 10 (10 = normal; 8-9 = within normal range; 7 = close to normal range, requires attention; 5-6 = requires attention and may require intervention; 3-4 = requires intervention; 1-2 requires immediate intervention). Results on capnography versus standard monitoring of the same study population was published previously. A total of 147 patients (74 in SM and 73 in IM) were included in the present study. Hypoxic events occurred in 62 patients (42%) and severe hypoxic events in 44 patients (29%), respectively. Baseline characteristics were equally distributed in both groups. IPI = 1, IPI < 7 as well as the parameters PetCO2 = 0 mmHg and apnea > 10 s had a high sensitivity for hypoxic and severe hypoxic events, respectively (IPI = 1: 81%/81% [hypoxic/severe hypoxic event], IPI < 7: 82%/88%, PetCO2: 69%/68%, apnea > 10 s: 84%/84%). All four parameters had a low specificity for both hypoxic and severe hypoxic events (IPI = 1: 13%/12%, IPI < 7: 7%/7%, PetCO2: 29%/27%, apnea > 10 s: 7%/7%). In multivariate analysis, only SM and PetCO2 = 0 mmHg were independent risk factors for hypoxia. IPI (IPI = 1 and IPI < 7) as well as the individual parameters PetCO2 = 0 mmHg and apnea > 10 s allow a fast and convenient conclusion on patients' respiratory status in a morbid patient population. Sensitivity is good for most parameters, but specificity is poor. In conclusion, IPI can be a useful metric to assess respiratory status during propofol-sedation in PEG-placement. However, IPI was not superior to PetCO2 and apnea > 10 s.


Assuntos
Gastrostomia , Propofol , Capnografia , Sedação Consciente , Humanos , Monitorização Fisiológica , Estudos Prospectivos , Respiração
16.
J Gastroenterol Hepatol ; 35(3): 401-407, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31222832

RESUMO

BACKGROUND AND AIM: A number of studies were able to show a reduction of hypoxemia episodes during procedural sedation through the use of capnography (CA). The present study investigates the number of episodes of hypoxemia during percutaneous endoscopic gastrostomy (PEG) placement with propofol sedation comparing standard monitoring (SM) versus SM with additional CA surveillance. METHODS: In this single center randomized controlled trial, 150 patients were prospectively randomized 1:1 in either the SM group or the CA group after stratification for ASA class, PEG method (push or pull method), presence of head and neck tumor, and tracheostomy. CA analysis was performed for all patients but was blinded for the endoscopic team in the SM group. RESULTS: In the SM group, 57% episodes of hypoxemia (SpO2  < 90% for > 15 s) and 41% episodes of severe hypoxemia (SpO2  < 85% for > 15 s) were observed in comparison with 28% and 20% in the CA group, respectively. Odds ratios for hypoxemia and severe hypoxemia were 0.29 (confidence interval 0.15-0.57; P = 0.0005) and 0.35 (confidence interval 0.17-0.73; P = 0.008) in favor of the CA group. On average, CA was able to detect imminent mild and severe hypoxemia 83 and 99 s before standard monitoring. Standard monitoring represented an independent risk factor for hypoxemia and severe hypoxemia. CONCLUSIONS: Respiratory complications of sedation during PEG placement are frequent events. CA is able to detect imminent hypoxemia at an early time point. This allows an early intervention and consecutively the avoidance of mild and severe hypoxemia. Therefore, CA monitoring can be recommended particularly during PEG insertion procedures.


Assuntos
Capnografia , Sedação Consciente/métodos , Endoscopia Gastrointestinal/métodos , Gastrostomia/métodos , Hipóxia/diagnóstico , Complicações Intraoperatórias/diagnóstico , Monitorização Fisiológica/métodos , Idoso , Feminino , Humanos , Hipóxia/prevenção & controle , Complicações Intraoperatórias/prevenção & controle , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
17.
Front Plant Sci ; 10: 1639, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31998332

RESUMO

Pathogen-associated molecular pattern (PAMP) recognition occurs by plasma membrane located receptors that induce among other processes nuclear gene expression. However, signaling to the nuclear compartment is restricted by the nuclear envelope and nuclear pore complexes. We show here that among the four Arabidopsis lamin homologs LITTLE NUCLEI/CROWDED NUCLEI (LINC/CRWN), LINC1 plays an important role in PTI and jasmonic acid (JA) signaling. We show that linc1 knock out mutants affect PAMP-triggered MAPK activation and growth inhibition, but not reactive oxygen species or callose accumulation. We also demonstrate that linc1 mutants are compromised in regulating PAMP-triggered pathogen-related genes, in particular encoding factors involved in JA signaling and responses. Expression of a number of JAZ domain proteins, the key JA-related transcription factor MYC2 as well as key MYB transcription factors and biosynthesis genes of both the indole and aliphatic glucosinolate pathways are changed in linc1 mutants. Moreover, PAMP triggers JA and JA-Ile accumulation in linc1 mutants, whereas salicylic acid levels are unchanged. Despite impairment in PAMP-triggered immunity, linc1 mutants still show basal immunity towards Pseudomonas syringae DC3000 strains. High JA levels usually render plants resistant to necrotrophic pathogen. Thus, linc1 mutants show enhanced resistance to Botrytis cinerea infection. In accordance with a general role of LINC1 in JA signaling, linc1 mutants are hypersensitive to growth inhibition to external JA. In summary, our findings show that the lamin-like LINC1 protein plays a key role in JA signaling and regulation of PTI responses in Arabidopsis.

18.
Elife ; 72018 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-30311601

RESUMO

Thiol-dependent redox regulation controls central processes in plant cells including photosynthesis. Thioredoxins reductively activate, for example, Calvin-Benson cycle enzymes. However, the mechanism of oxidative inactivation is unknown despite its importance for efficient regulation. Here, the abundant 2-cysteine peroxiredoxin (2-CysPrx), but not its site-directed variants, mediates rapid inactivation of reductively activated fructose-1,6-bisphosphatase and NADPH-dependent malate dehydrogenase (MDH) in the presence of the proper thioredoxins. Deactivation of phosphoribulokinase (PRK) and MDH was compromised in 2cysprxAB mutant plants upon light/dark transition compared to wildtype. The decisive role of 2-CysPrx in regulating photosynthesis was evident from reoxidation kinetics of ferredoxin upon darkening of intact leaves since its half time decreased 3.5-times in 2cysprxAB. The disadvantage of inefficient deactivation turned into an advantage in fluctuating light. Physiological parameters like MDH and PRK inactivation, photosynthetic kinetics and response to fluctuating light fully recovered in 2cysprxAB mutants complemented with 2-CysPrxA underlining the significance of 2-CysPrx. The results show that the 2-CysPrx serves as electron sink in the thiol network important to oxidize reductively activated proteins and represents the missing link in the reversal of thioredoxin-dependent regulation.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Cloroplastos/metabolismo , Cisteína/metabolismo , Peroxirredoxinas/metabolismo , Tiorredoxinas/metabolismo , Arabidopsis/efeitos da radiação , Clorofila A/metabolismo , Simulação por Computador , Fluorescência , Genótipo , Meia-Vida , Cinética , Luz , Malato Desidrogenase/metabolismo , Modelos Biológicos , Mutação/genética , NADP/metabolismo , Oxirredução , Fenótipo , Fotossíntese , Espectroscopia de Luz Próxima ao Infravermelho
19.
Sante Publique ; 30(1): 105-113, 2018.
Artigo em Francês | MEDLINE | ID: mdl-29589682

RESUMO

INTRODUCTION: Organizational culture, a frequently ignored concept, affects job satisfaction and productivity in organizations. OBJECTIVE: To determine the factors associated with the strength of organizational culture (OC) in Mono / Couffo regional hospital in Lokossa in Benin. METHODS: This cross-sectional and analytical study involved 121 workers of Mono/Couffo hospital in March 2015. Data on the strength of OC was collected using a questionnaire based on the validated tool proposed by Cameron and Quinn (2006). Logistic regression was performed to explore the nature of the relationship between the independent variables and OC using Odds ratios. RESULTS: 62% of the surveyed subjects had a positive perception of organizational culture. This perception was statistically associated with managerial factors (moral support of workers and type of relationship with the executive staff). The risk of perceiving a low strength of OC was sixfold higher OR = 3.78, 95% CI (1.08 - 13.22) among subjects who felt they did not have moral support from executive staff than in those who perceived this moral support. The risk of perceiving a weak OC was higher among subjects who considered relations with the staff to be uncordial [OR = 14.32, 95% CI (4.35 - 47.11)] compared to those who considered these relations to be cordial. CONCLUSION: Human resource management factors were more closely associated with the strength of organizational culture. Hospital managers should pay more attention to these factors in their hospitals to promote better institutional performance.


Assuntos
Atitude do Pessoal de Saúde , Cultura Organizacional , Adulto , Benin , Estudos Transversais , Feminino , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade
20.
BMC Genomics ; 16: 430, 2015 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-26044734

RESUMO

BACKGROUND: Fusarium head blight (FHB) and Septoria tritici blotch (STB) severely impair wheat production. With the aim to further elucidate the genetic architecture underlying FHB and STB resistance, we phenotyped 1604 European wheat hybrids and their 135 parental lines for FHB and STB disease severities and determined genotypes at 17,372 single-nucleotide polymorphic loci. RESULTS: Cross-validated association mapping revealed the absence of large effect QTL for both traits. Genomic selection showed a three times higher prediction accuracy for FHB than STB disease severity for test sets largely unrelated to the training sets. CONCLUSIONS: Our findings suggest that the genetic architecture is less complex and, hence, can be more properly tackled to perform accurate prediction for FHB than STB disease severity. Consequently, FHB disease severity is an interesting model trait to fine-tune genomic selection models exploiting beyond relatedness also knowledge of the genetic architecture.


Assuntos
Ascomicetos/fisiologia , Resistência à Doença/genética , Fusarium/fisiologia , Doenças das Plantas/genética , Triticum/genética , Mapeamento Cromossômico , Europa (Continente) , Genótipo , Fenótipo , Doenças das Plantas/etiologia , Doenças das Plantas/microbiologia , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Triticum/microbiologia
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