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1.
J Dairy Sci ; 107(5): 3292-3305, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38056565

RESUMO

Heat stress causes barrier dysfunction and inflammation of the small intestine of several species. However, less is known about the molecular and cellular mechanisms underlying the response of the bovine large intestine to hyperthermia. We aimed to identify changes in the colon of dairy cows in response to constant heat stress using a proteomic approach. Eighteen lactating Holstein dairy cows were kept under constant thermoneutral conditions (16°C and 68% relative humidity [RH]; temperature-humidity index [THI] = 60) for 6 d (period 1) with free access to feed and water. Thereafter, 6 cows were equally allocated to (1) thermoneutral condition with ad libitum feeding (TNAL; 16°C, RH = 68%, THI = 60), (2) heat stress condition (HS; 28°C, RH = 50%, THI = 76) with ad libitum feeding, or (3) pair-feeding at thermoneutrality (TNPF; 16°C, RH = 68%, THI = 60) for another 7 d (period 2). Rectal temperature, milk yield, dry matter and water intake were monitored daily. Then, cows were slaughtered and colon mucosa samples were taken for proteomic analysis. Physiological data were analyzed by ANOVA and colon proteome data were processed using DESeq2 package in R. Rectal temperature was significantly higher in HS than in TNPF and TNAL cows in period 2. Proteomic analysis revealed an enrichment of activated pathways related to colonic barrier function and inflammation, heat shock proteins, AA metabolism, reduced overall protein synthesis rate, and post-transcriptional regulation induced by heat stress. Further regulations were found for enzymes of the tricarboxylic acid cycle and components of the mitochondrial electron transport chain, presumably to reduce the generation of reactive oxygen species, maintain cellular ATP levels, and prevent apoptosis in the colon of HS cows. These results highlight the cellular, extracellular, and mitochondrial adaptations of the colon during heat stress and suggest a dysfunction of the hindgut barrier integrity potentially resulting in a "leaky" colon.

2.
J Dairy Sci ; 107(7): 5162-5177, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38431250

RESUMO

The intestinal microbiota plays a pivotal role in digestive processes and maintains gut health and intestinal homeostasis. These functions may be compromised by increased environmental heat, which in turn reduces feed intake and gut integrity and activates the intestinal immune system. It remains unknown whether high ambient temperatures, which cause heat stress (HS) in dairy cows, disturb the eubiosis of the microbial community, and if so, to which extent the reduction in feed intake and the impairment of circulating and intestinal metabolites account for the alterations of the jejunal microbiota. To address these questions, jejunal digesta, mucosa, and plasma samples were collected from cows exposed to heat stress (HS; 28°C, temperature-humidity index [THI] = 76, n = 10), control conditions (CON; 16°C, THI = 60, n = 10), or pair-fed (PF; 16°C, THI = 60, n = 10) for 7 d. Digesta fluids were examined for pH, acetate, nonesterified fatty acids (NEFA), glucose, and lactate, and plasma samples were analyzed for glucose, lactate, BHB, triglycerides, NEFA, creatinine, and urea. The microbiota of the digesta and mucosa samples were analyzed by 16S rRNA sequencing. The α-diversity was higher in mucosa than digesta but was not affected by high ambient temperatures. However, the mucosa-associated microbiota appeared more responsive to ambient heat than the digesta microbiome. The adaptive responses under HS conditions comprised an increased mucosal abundance of Bifidobacteriaceae, Succinivibrionaceae UCG-001, Clostridia and Lactobacillus. In the digesta, HS has exerted effects on microbial abundance of Colidextribacter, and Lachnospiraceae UCG-008. Several correlations between plasma or intestinal metabolites and microbiota were elucidated, including Methanobacteriaceae correlating positively with plasma BHB and digesta glucose concentrations. Moreover, the reduction in feed intake during HS had non-negligible effects on microbial diversity and the abundance of certain taxa, underpinning the importance of nutrient supply on maintaining intestinal homeostasis.


Assuntos
Microbioma Gastrointestinal , Jejuno , Animais , Bovinos , Feminino , Jejuno/metabolismo , Jejuno/microbiologia , Temperatura Alta , Microbiota
3.
J Craniofac Surg ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39028196

RESUMO

Positional skull deformities have been on the rise for decades and can be treated with molding helmets in early childhood. Parents often fear later cosmetic stigmatization, but also a reduced quality of life (QoL) during treatment. The aim of this study was to examine therapy results in our patient collection from a new perspective. Cranial vault asymmetry (CVA), cranial vault asymmetry index (CVAI), and cranial index (CI) were compared before and after molding helmet therapy. Correction was defined by a decrease in CVA <3.5 mm and CI <90%. Subjective therapy outcome, side effects and QoL from the parents' perspective were determined using a questionnaire. There were 25 patients included. Differences between pretherapeutic and posttherapeutic CVA, CVAI, and CI were significant (P<0.01). An objective correction according to the defined values was observed in only 12% of cases. However, 76% of parents stated that their child's skull shape was normal after therapy. There were 60 side effects reported in 23 cases. The QoL of 21 children was assessed as unimpaired during helmet therapy. Even though complete normalization was rarely observed, the parameters were significantly different after therapy, and subjective reduction in skull deformity was common.

4.
Int J Colorectal Dis ; 38(1): 80, 2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-36964828

RESUMO

PURPOSE: The effectiveness of modern perioperative treatment concepts has been demonstrated in several studies and meta-analyses. Despite good evidence, limited implementation of the fast track (FT) concept is still a widespread concern. To assess the status quo in Austrian and German hospitals, a survey on the implementation of FT measures was conducted among members of the German Society of General and Visceralsurgery (DGAV), the German Society of Coloproctology (DGK) and the Austrian Society of Surgery (OEGCH) to analyze where there is potential for improvement. METHODS: Twenty questions on perioperative care of colorectal surgery patients were sent to the members of the DGAV, DGK and OEGCH using the online survey tool SurveyMonkey®. Descriptive data analysis was performed using Microsoft Excel. RESULTS: While some of the FT measures have already been routinely adopted in clinical practice (e.g. minimally invasive surgical approach, early mobilization and diet buildup), for other components there are discrepancies between current recommendations and present implementation (e.g. the use of local nerve blocks to provide opioid-sparing analgesia or the use of abdominal drains). CONCLUSION: The implementation of the FT concept in Austria and Germany is still in need of improvement. Particularly regarding the use of abdominal drains and postoperative analgesia, there is a tendency to stick to traditional structures. To overcome the issues with FT implementation, the development of an evidence-based S3 guideline for perioperative care, followed by the founding of a surgical working group to conduct a structured education and certification process, may lead to significant improvements in perioperative patient care.


Assuntos
Cirurgia Colorretal , Procedimentos Cirúrgicos do Sistema Digestório , Cirurgiões , Humanos , Áustria , Inquéritos e Questionários , Analgésicos Opioides
5.
J Dairy Sci ; 106(4): 3008-3022, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36894431

RESUMO

Heat stress negatively affects the metabolism and physiology of the bovine gut. However, it is not known whether heat stress induces an inflammatory response in mesenteric lymph nodes (MLN), the primary origin of gut immune cells, and thus contributes to inflammatory processes in the circulation. Therefore, our objective was to elucidate the effects of chronic heat stress on the systemic activation of acute-phase response in blood, proinflammatory cytokine production in peripheral blood mononuclear cells (PBMC), and the activation of the toll-like receptor signaling (TLR) 2/4 pathway in MLN leucocytes and their chemokines and chemokine receptor profiles in Holstein cows. Primiparous Holstein cows (n = 30; 169 ± 9 d in milk) were exposed to a temperature-humidity index (THI) of 60 [16°C, 63% relative humidity (RH)] for 6 d. Thereafter, cows were evenly assigned to 3 groups: heat-stressed (HS; 28°C, 50% RH, THI = 76), control (CON; 16°C, 69% RH, THI = 60), or pair-feeding (PF; 16°C, 69% RH, THI = 60) for 7 d. On d 6, PBMC were isolated and on d 7 MLN. Plasma haptoglobin, TNFα, and IFNγ concentrations increased more in HS than CON cows. Concomitantly, TNFA mRNA abundance was higher in PBMC and MLN leucocytes of HS than PF cows, whereas IFNG mRNA abundance tended to be higher in MLN leucocytes of HS than PF cows, but not for chemokines (CCL20, CCL25) or chemokine receptors (ITGB7, CCR6, CCR7, CCR9). Furthermore, the TLR2 protein expression tended to be more abundant in MLN leucocytes of HS than PF cows. These results suggest that heat stress induced an adaptive immune response in blood, PBMC, and MLN leukocytes involving the acute-phase protein haptoglobin, proinflammatory cytokine production, and TLR2 signaling in MLN leucocytes. However, chemokines regulating the leucocyte trafficking between MLN and gut seem not to be involved in the adaptive immune response to heat stress.


Assuntos
Lactação , Leucócitos Mononucleares , Feminino , Bovinos , Animais , Lactação/fisiologia , Haptoglobinas/metabolismo , Receptor 2 Toll-Like/metabolismo , Leite/metabolismo , Resposta ao Choque Térmico , Leucócitos , Imunidade Adaptativa , Linfonodos , Temperatura Alta
6.
Zentralbl Chir ; 148(5): 406-414, 2023 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-34666401

RESUMO

The perioperative management of colorectal resections is often dominated by traditional procedures and a strong focus on safety. Evidence-based measures such as those established in Fast Track or ERAS programs, are rarely applied in a standardised manner. As part of elective colorectal surgery, many patients therefore continue to routinely receive central venous access, peridural catheters, urinary catheters, drains and/or gastric tubes ("Big Five" of invasiveness). This article presents the currently available evidence on these measures in colorectal surgery. In addition, results relating to the "Big Five" from the author's own centre are presented. This review shows that the "Big Five" of invasiveness are clinically unnecessary or supported by evidence. In addition, they often impair the patient's function.

7.
Zentralbl Chir ; 148(5): 454-459, 2023 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-36063840

RESUMO

BACKGROUND: ERAS (Enhanced Recovery After Surgery) describes a multimodal, interdisciplinary and interprofessional treatment concept that optimizes the postoperative convalescence of the patient through the use of evidence-based measures. GOAL OF THE WORK: The aim of this article is to examine the economic feasibility of the concept in the German DRG system. MATERIAL AND METHODS: Since August 2019, patients have been treated in our clinic according to the later certified ERAS concept. The last 20 patients before ERAS implementation are compared below with 20 patients after ERAS implementation, who were identified using a matched pair analysis. In addition to the comparison of costs and revenues, the clinical outcome of the patients is also presented. RESULTS: The cases of the patients in the pre-ERAS cohort caused median costs of € 7432.83. BWR of 3.38 were billable. The resulting DRG revenue for the patients in this group amounted to € 11325.78. The proceeds generated in the end amounted to € 4575.14. The cases of patients in the ERAS cohort resulted in costs of € 5582.96. BWR of 2.84 could be billed. The DRG proceeds for the patients in this group therefore amounted to € 10014.18. The profit generated was thus € 4993.84. DISCUSSION: The cost reduction generated by ERAS was comparable to the "loss" caused by the BWR decrease. ERAS is therefore also possible to cover costs in the German DRG system.


Assuntos
Neoplasias Colorretais , Grupos Diagnósticos Relacionados , Humanos , Tempo de Internação
8.
Langenbecks Arch Surg ; 407(7): 2981-2986, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35925378

RESUMO

PURPOSE: ERAS® (Enhanced Recovery After Surgery) describes a multimodal, interdisciplinary, and interprofessional treatment concept that optimizes the postoperative convalescence of the patient through the use of evidence-based measures. Goal of the work. The aim of this article is to examine the economic feasibility of the ERAS® concept in the German DRG (diagnosis-related groups) system. MATERIAL AND METHODS: Since August 2019, patients have been treated in our clinic according to the later certified ERAS® concept. The last 50 patients before ERAS® implementation are compared below with 50 patients after ERAS® implementation, who were identified using a matched pair analysis. In addition to the comparison of costs and revenues, the clinical outcome of the patients is also presented. RESULTS: The cases of the patients in the pre-ERAS® cohort caused median costs of € 7432.83. BWR (valuation ratio) of 3.38 were billable. The resulting DRG revenue for the patients in this group amounted to € 11,325.78. The proceeds generated in the end amounted to € 4575.14. The cases of patients in the ERAS® cohort resulted in costs of € 5582.96. BWR of 2.84 could be billed. The DRG proceeds for the patients in this group therefore amounted to € 10,014.18. The profit generated was thus € 4993.84. CONCLUSION: The cost reduction generated by ERAS® was more pronounced than the "loss" due to the decrease in BWR. ERAS® is therefore also possible in the German DRG system at absolutely cost-covering levels.


Assuntos
Neoplasias Colorretais , Recuperação Pós-Cirúrgica Melhorada , Humanos , Custos de Cuidados de Saúde , Grupos Diagnósticos Relacionados , Tempo de Internação
9.
Proc Natl Acad Sci U S A ; 116(21): 10333-10338, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31064871

RESUMO

High ambient temperature has multiple potential effects on the organism such as hyperthermia, endotoxemia, and/or systemic inflammation. However, it is often difficult to discriminate between cause and consequence of phenotypic effects, such as the indirect influence of heat stress via reduced food intake. Lactating dairy cows are a particularly sensitive model to examine the effects of heat stress due to their intensive metabolic heat production and small surface:volume ratio. Results from this model show heat stress directly induced a so-far unknown infiltration of yet uncategorized cells into the mucosa and submucosa of the jejunum. Due to a pair-feeding design, we can exclude this effect being a consequence of the concurrent heat-induced reduction in feed intake. Isolation and characterization of the infiltrating cells using laser capture microdissection and RNA sequencing indicated a myeloic origin and macrophage-like phenotype. Furthermore, targeted transcriptome analyses provided evidence of activated immune- and phagocytosis-related pathways with LPS and cytokines as upstream regulators directly associated with heat stress. Finally, we obtained indication that heat stress may directly alter jejunal tight junction proteins suggesting an impaired intestinal barrier. The penetration of toxic and bacterial compounds during heat stress may have triggered a modulated immune repertoire and induced an antioxidative defense mechanism to maintain homeostasis between commensal bacteria and the jejunal immune system. Our bovine model indicates direct effects of heat stress on the jejunum of mammals already at moderately elevated ambient temperature. These results need to be considered when developing concepts to combat the negative consequences of heat stress.


Assuntos
Resposta ao Choque Térmico/imunologia , Resposta ao Choque Térmico/fisiologia , Jejuno/imunologia , Jejuno/fisiologia , Animais , Bovinos , Feminino , Transtornos de Estresse por Calor/imunologia , Transtornos de Estresse por Calor/fisiopatologia , Temperatura Alta , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/fisiopatologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/fisiologia , Jejuno/metabolismo , Lactação/imunologia , Lactação/metabolismo , Lactação/fisiologia , Proteínas de Junções Íntimas/imunologia , Proteínas de Junções Íntimas/metabolismo
10.
Arch Gynecol Obstet ; 306(4): 937-942, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34874493

RESUMO

PURPOSE: Perioperative cognitive dysfunction can be observed in all age groups of patients. Sometimes, this is more stressful to the patient than the actual surgical wound. Enhanced recovery after surgery pathways screen for patients at risk and lead to early post-surgical intervention. To prevent cognitive dysfunction, a prehabilitation approach might be useful. METHODS: This systematic literature review provides an overview on the current knowledge on prehabilitation for cognitive dysfunction for gynaecological patients by searching the National Library of Medicine (PubMed) in February 2020 to identify publications regarding presurgical cognitive training with three different search terms. RESULTS: 501 articles were identified and after screening for eligibility five were left for further analysis. Generally, cognitive function is split into several cognitive aspects like anxiety or memory, speed, attention, flexibility or problem-solving functions. Each of these aspects can/need to be trained to show an improvement after general anaesthesia. Training possibilities range from relaxation methods via music, one-on-one personal training sessions to electronically supported training units. CONCLUSION: Prehabilitation of the cognitive function can be split in different cognitive domains. Each of these domains seem to be influenced by training. The training itself can be based on applications or known relaxation methods or even old-fashioned board games. The evidence is, however, still low and there is a need for further studies.


Assuntos
Transtornos Cognitivos , Disfunção Cognitiva , Ginecologia , Cognição , Transtornos Cognitivos/prevenção & controle , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/prevenção & controle , Humanos , Estados Unidos
11.
Arterioscler Thromb Vasc Biol ; 40(1): 159-174, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31619060

RESUMO

OBJECTIVE: In proliferative retinopathies, complications derived from neovascularization cause blindness. During early disease, pericyte's apoptosis contributes to endothelial dysfunction and leakage. Hypoxia then drives VEGF (vascular endothelial growth factor) secretion and pathological neoangiogenesis. Cardiac ANP (atrial natriuretic peptide) contributes to systemic microcirculatory homeostasis. ANP is also formed in the retina, with unclear functions. Here, we characterized whether endogenously formed ANP regulates retinal (neo)angiogenesis. Approach and Results: Retinal vascular development and ischemia-driven neovascularization were studied in mice with global deletion of GC-A (guanylyl cyclase-A), the cGMP (cyclic guanosine monophosphate)-forming ANP receptor. Mice with a floxed GC-A gene were interbred with Tie2-Cre, GFAP-Cre, or PDGF-Rß-CreERT2 lines to dissect the endothelial, astrocyte versus pericyte-mediated actions of ANP in vivo. In neonates with global GC-A deletion (KO), vascular development was mildly delayed. Moreover, such KO mice showed augmented vascular regression and exacerbated ischemia-driven neovascularization in the model of oxygen-induced retinopathy. Notably, absence of GC-A in endothelial cells did not impact retinal vascular development or pathological neovascularization. In vitro ANP/GC-A/cGMP signaling, via activation of cGMP-dependent protein kinase I, inhibited hypoxia-driven astrocyte's VEGF secretion and TGF-ß (transforming growth factor beta)-induced pericyte apoptosis. In neonates lacking ANP/GC-A signaling in astrocytes, vascular development and hyperoxia-driven vascular regression were unaltered; ischemia-induced neovascularization was modestly increased. Remarkably, inactivation of GC-A in pericytes retarded physiological retinal vascularization and markedly enhanced cell apoptosis, vascular regression, and subsequent neovascularization in oxygen-induced retinopathy. CONCLUSIONS: Protective pericyte effects of the ANP/GC-A/cGMP pathway counterregulate the initiation and progression of experimental proliferative retinopathy. Our observations indicate augmentation of endogenous pericyte ANP signaling as target for treatment of retinopathies associated with neovascularization.


Assuntos
Astrócitos/metabolismo , GMP Cíclico/genética , Regulação da Expressão Gênica no Desenvolvimento , Peptídeos Natriuréticos/metabolismo , Pericitos/metabolismo , RNA/genética , Neovascularização Retiniana/genética , Animais , Animais Recém-Nascidos , Apoptose , Astrócitos/patologia , Células Cultivadas , GMP Cíclico/biossíntese , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Immunoblotting , Camundongos , Camundongos Transgênicos , Pericitos/patologia , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/patologia , Transdução de Sinais
12.
Zentralbl Chir ; 146(6): 570-578, 2021 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-34587644

RESUMO

COVID-19 has led to profound changes in the world as we have known it. Due to the sharp increase in intensive care, COVID patients, elective admissions and interventions have been postponed. But emergencies such as myocardial infarction have also decreased. The present study deals with the effects of the COVID pandemic on visceral surgical emergencies on the basis of 5 indicator operations. Routine data from 73 acute hospitals of the Helios Group were evaluated for this purpose. The interventions that were carried out between March 13, 2020 and March 12, 2021 were included. The data was compared with the period from March 13, 2019 to March 12, 2020. The number of interventions in serious emergencies (ileus, mesenteric ischemia and ulcer perforation) has remained constant. However, the length of stay in hospital in the pandemic year 2020 was significantly shorter than in the reference year 2019. The number of cholecystectomies and appendectomies in the pandemic year was significantly lower than in the reference year 2019. The outcome parameters intensive care, invasive ventilation and hospital mortality were comparable for the two periods for these interventions.


Assuntos
COVID-19 , Apendicectomia , Hospitais , Humanos , Pandemias , Estudos Retrospectivos , SARS-CoV-2
13.
Zentralbl Chir ; 146(3): 260-268, 2021 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-34154006

RESUMO

Modern concepts of perioperative treatment place great value on the active role of the patient. In order to make this possible, intensive patient support is necessary. The position of the ERAS nurse has developed from this necessity. She is the primary contact for the patient before, during and after the operation. The conceptual creation and continuous further development of an ERAS concept may primarily be a medical activity, but the day-to-day work on the patient and filling the concept with life is mainly done by an ERAS nurse. Her main tasks are preoperative patient education, daily patient visits during the inpatient stay, filling in the documentation, ongoing communication with nursing staff and monitoring compliance with the ERAS requirements of all team members involved. It is accordingly important to create the position of an ERAS nurse and to integrate her as a valuable member of the team. In the following article, which is based on our experience as a certified ERAS centre, the job description in detail is presented, including tasks, importance and suggested solutions for common problems.


Assuntos
Recursos Humanos de Enfermagem , Feminino , Humanos
14.
BMC Oral Health ; 20(1): 148, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32429904

RESUMO

BACKGROUND: Periodontitis is a chronic inflammation of the tooth supporting structures that finally can lead to tooth loss. As chronic periodontitis is associated with systemic diseases multiple approaches have been followed to support regeneration of the destructed tissue. But very few materials are actually used in the clinic. A new and promising group of biomaterials with advantageous biomechanical properties that have the ability to support periodontal regeneration are self-assembling peptides (SAP). However, there is still a lack of 3D periodontal models that can evaluate the migration potential of such novel materials. METHODS: All experiments were performed with primary human periodontal ligament fibroblasts (HPLF). Migration capacity was assessed in a three-dimensional model of the human periodontal ligament by measuring the migration distance of viable cells on coated (Enamel Matrix Protein (EMP), P11-4, collagen I) or uncoated human dentin. Cellular metabolic activity on P11-4 hydrogels was assessed by a metabolic activity assay. Deposition of ECM molecules in a P11-4 hydrogel was visualized by immunostaining of collagen I and III and fibrillin I. RESULTS: The 3D periodontal model was feasible to show the positive effect of EMP for periodontal regeneration. Subsequently, self-assembling peptide P11-4 was used to evaluate its capacity to support regenerative processes in the 3D periodontal model. HPLF coverage of the dentin surface coated with P11-4 increased significantly over time, even though delayed compared to EMP. Cell viability increased and inclusion of ECM proteins into the biomaterial was shown. CONCLUSION: The presented results indicate that the 3D periodontal model is feasible to assess periodontal defect coverage and that P11-4 serves as an efficient supporter of regenerative processes in the periodontal ligament. CLINICAL RELEVANCE: The establishment of building-block synthetic polymers offers new opportunities for clinical application in dentistry. Self-assembling peptides represent a new generation of biomaterials as they are able to respond dynamically to the changing environment of the biological surrounding. Especially in the context of peri-implant disease prevention and treatment they enable the implementation of new concepts.


Assuntos
Materiais Biocompatíveis/uso terapêutico , Ligamento Periodontal , Periodontite/terapia , Periodonto/fisiologia , Engenharia Tecidual/métodos , Materiais Biocompatíveis/química , Fibroblastos , Humanos , Regeneração
15.
Circulation ; 138(5): 494-508, 2018 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-29626067

RESUMO

BACKGROUND: Peripheral vascular resistance has a major impact on arterial blood pressure levels. Endothelial C-type natriuretic peptide (CNP) participates in the local regulation of vascular tone, but the target cells remain controversial. The cGMP-producing guanylyl cyclase-B (GC-B) receptor for CNP is expressed in vascular smooth muscle cells (SMCs). However, whereas endothelial cell-specific CNP knockout mice are hypertensive, mice with deletion of GC-B in vascular SMCs have unaltered blood pressure. METHODS: We analyzed whether the vasodilating response to CNP changes along the vascular tree, ie, whether the GC-B receptor is expressed in microvascular types of cells. Mice with a floxed GC-B ( Npr2) gene were interbred with Tie2-Cre or PDGF-Rß-Cre ERT2 lines to develop mice lacking GC-B in endothelial cells or in precapillary arteriolar SMCs and capillary pericytes. Intravital microscopy, invasive and noninvasive hemodynamics, fluorescence energy transfer studies of pericyte cAMP levels in situ, and renal physiology were combined to dissect whether and how CNP/GC-B/cGMP signaling modulates microcirculatory tone and blood pressure. RESULTS: Intravital microscopy studies revealed that the vasodilatatory effect of CNP increases toward small-diameter arterioles and capillaries. CNP consistently did not prevent endothelin-1-induced acute constrictions of proximal arterioles, but fully reversed endothelin effects in precapillary arterioles and capillaries. Here, the GC-B receptor is expressed both in endothelial and mural cells, ie, in pericytes. It is notable that the vasodilatatory effects of CNP were preserved in mice with endothelial GC-B deletion, but abolished in mice lacking GC-B in microcirculatory SMCs and pericytes. CNP, via GC-B/cGMP signaling, modulates 2 signaling cascades in pericytes: it activates cGMP-dependent protein kinase I to phosphorylate downstream targets such as the cytoskeleton-associated vasodilator-activated phosphoprotein, and it inhibits phosphodiesterase 3A, thereby enhancing pericyte cAMP levels. These pathways ultimately prevent endothelin-induced increases of pericyte calcium levels and pericyte contraction. Mice with deletion of GC-B in microcirculatory SMCs and pericytes have elevated peripheral resistance and chronic arterial hypertension without a change in renal function. CONCLUSIONS: Our studies indicate that endothelial CNP regulates distal arteriolar and capillary blood flow. CNP-induced GC-B/cGMP signaling in microvascular SMCs and pericytes is essential for the maintenance of normal microvascular resistance and blood pressure.


Assuntos
Pressão Arterial/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Hipertensão/metabolismo , Microcirculação/efeitos dos fármacos , Microvasos/efeitos dos fármacos , Peptídeo Natriurético Tipo C/farmacologia , Pericitos/metabolismo , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Animais , Técnicas Biossensoriais , Sinalização do Cálcio/efeitos dos fármacos , Células Cultivadas , GMP Cíclico/metabolismo , Células Endoteliais/metabolismo , Transferência Ressonante de Energia de Fluorescência , Predisposição Genética para Doença , Hipertensão/genética , Hipertensão/fisiopatologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microvasos/metabolismo , Microvasos/fisiopatologia , Peptídeo Natriurético Tipo C/metabolismo , Comunicação Parácrina/efeitos dos fármacos , Fenótipo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/deficiência , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Receptores do Fator Natriurético Atrial/deficiência , Receptores do Fator Natriurético Atrial/genética
16.
Sensors (Basel) ; 14(11): 20975-99, 2014 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-25384007

RESUMO

The amount of liquid water in snow characterizes the wetness of a snowpack. Its temporal evolution plays an important role for wet-snow avalanche prediction, as well as the onset of meltwater release and water availability estimations within a river basin. However, it is still a challenge and a not yet satisfyingly solved issue to measure the liquid water content (LWC) in snow with conventional in situ and remote sensing techniques. We propose a new approach based on the attenuation of microwave radiation in the L-band emitted by the satellites of the Global Positioning System (GPS). For this purpose, we performed a continuous low-cost GPS measurement experiment at the Weissfluhjoch test site in Switzerland, during the snow melt period in 2013. As a measure of signal strength, we analyzed the carrier-to-noise power density ratio (C/N0) and developed a procedure to normalize these data. The bulk volumetric LWC was determined based on assumptions for attenuation, reflection and refraction of radiation in wet snow. The onset of melt, as well as daily melt-freeze cycles were clearly detected. The temporal evolution of the LWC was closely related to the meteorological and snow-hydrological data. Due to its non-destructive setup, its cost-efficiency and global availability, this approach has the potential to be implemented in distributed sensor networks for avalanche prediction or basin-wide melt onset measurements.

18.
Med Probl Perform Art ; 29(3): 168-73, 2014 09.
Artigo em Inglês | MEDLINE | ID: mdl-25194115

RESUMO

OBJECTIVE: The physical requirement profile for professional dancers has changed significantly during the past decades. The aim of this first comparative study is to present a differentiated analysis of work-related traumatic injuries sustained by professional ballet dancers at the end of the 20th century (1994/95) and now (2011/12). METHODS: The data for evaluation were obtained from work accident reports (n=241; 1994/95, n=155; 2011/12, n=86) from three Berlin theatres. RESULTS: An increase in incidence of injuries could be observed only in male dancers (0.3 injuries/yr in 1994/95 vs 0.4/yr in 2011/12). Numerous significant differences were found between injuries in the earlier time span and in the present. Movement contents resulting in traumatic injuries have changed. Furthermore, differences as to injury types, injured body region, nature of causes, dance activities prior to injury, and attitude after sustaining an occupational accident were observed. The lower extremity remained the most common injury site (66.7% in 1994/95 vs 57.0% in 2011/12, p=0.697. (The frequency rate of traumatic injuries to the spine has increased significantly (13.5% in 1994/95 vs 24.1% in 2011/12, p=0.026, (with injuries to the lumbar spine region more than tripled (5.8% vs 20.3% respectively). Few deviations were observed as to injury locations and organizational and time aspects (e.g., time of year of injury). CONCLUSION: Dance is progressing as evidenced by the numerous aspects resulting in traumatic injuries. It is not organizational or time changes but rather work- and content-related factors that result in significant differences between past and present injuries.


Assuntos
Osso e Ossos/lesões , Dança/lesões , Traumatismos Ocupacionais/epidemiologia , Ferimentos e Lesões/epidemiologia , Adolescente , Adulto , Comorbidade , Contusões/epidemiologia , Dança/estatística & dados numéricos , Feminino , Alemanha/epidemiologia , Humanos , Traumatismos da Perna/epidemiologia , Masculino , Prevalência , Fatores de Risco , Entorses e Distensões/epidemiologia , Fatores de Tempo , População Urbana/estatística & dados numéricos , Adulto Jovem
19.
Med Probl Perform Art ; 29(1): 32-6, 2014 03.
Artigo em Inglês | MEDLINE | ID: mdl-24647460

RESUMO

OBJECTIVE: Reducing work-related health hazards at the different theatre workplaces is one aspect of preventive options in professional dance. This also applies to hazards on the highly variable theatrical stage areas. However, detailed information on these stages and their risks is not available. The aim of this study was to analyze and evaluate work-related traumatic injuries in the stage area. METHODS: The basis for the evaluation was accident reports, from the German National Statutory Insurance, of work-related traumatic injuries occurring on stage in professional dancers (n=790: 407 males, 383 females) over a 17-year period (1995-2011). RESULTS: Most (79.4%) of the accidents on stage occurred during an ongoing performance (frequency: 10.1/100 performances), with only 19.7% occurring during rehearsals on stage (p<0.001). Due to the sustained injury, 30.2% of the dancers sustained a time-loss injury. Most (57.7%) of the injured dancers were older than 25 years. Of the accidents, 59.3% were initiated by a definably extrinsic cause, with 40.7% caused by intrinsic factors (p<0.001). Injuries were most commonly caused by the "partner" (21.7%) or "floor" (21.0%). The lower extremity was the most commonly affected body region (63.6%) (p<0.001). CONCLUSION: Stage performances seem to carry an increased injury risk compared to rehearsals. The "risk" of on-stage work is spread across various factors that seem to be stage-specific. There is a need for further qualitative and quantitative research to be able to classify the stage as workplace more precisely.


Assuntos
Acidentes de Trabalho/estatística & dados numéricos , Dança/lesões , Pisos e Cobertura de Pisos , Traumatismos Ocupacionais/epidemiologia , Entorses e Distensões/epidemiologia , Adulto , Fatores Etários , Osso e Ossos/lesões , Feminino , Alemanha , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Ferimentos e Lesões/epidemiologia , Adulto Jovem
20.
Med Probl Perform Art ; 28(1): 19-23, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23462900

RESUMO

Eating is a central part in human (social) life. Athletic performance and physical attractiveness are linked to appropriate nutritional behavior, especially for performing artists. Eating behavior and nutrition knowledge have not been examined in musical theatre students so far, which this study aims to analyze. We administered a cross-sectional questionnaire study to 37 musical theatre students. Results for the Eating Disorder Examination-Questionnaire (EDE-Q) showed non-pathological values for 92% of all participants, but 81% of participants answered correctly on only 30-59% of questions on the General Nutrition Knowledge Questionnaire (GNKQ). Our study results reveal the need for specific nutritional knowledge transfer programs for this target group.


Assuntos
Comportamento Alimentar/psicologia , Preferências Alimentares/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Música , Estudantes/psicologia , Adolescente , Adulto , Estudos Transversais , Feminino , Alemanha , Humanos , Masculino , Inquéritos Nutricionais , Necessidades Nutricionais , Valor Nutritivo , Vigilância da População , Inquéritos e Questionários , Universidades , Adulto Jovem
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