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1.
CVIR Endovasc ; 7(1): 63, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39141215

RESUMO

INTRODUCTION: Ureterovascular fistula (UVF) is a rare but potentially life-threatening condition. Since its primary description by Moschkowitz in 1908, many case reports, studies and reviews have been written about this condition with the suggestive symptoms and risk factors repeatedly discussed. This study will be focusing on the different locations of 532 out of 605 fistulae published from 1908 up to 2022 besides eight new patients of our own. MATERIAL AND METHODS: A systematic review of the literature started using PubMed database searching for "ureteroarterial fistula", "arteriovascular fistula" and "uretero vascular fistula" was performed yielding 122, 62 and 188 results respectively. Those studies and the cited literature in each study were examined to include studies, which did not appear in the primary search. A total of 605 patients in 315 publications were gathered. Only studies mentioning new patients, a clear indication of the location of the UVF, the presence/absence of urinary diversion (UD) as well as the type of UD if present were included. Ten duplicates as well as studies lacking information regarding the UVF and/or the UD (seven publications with 63 patients) were excluded, with 298 publications including 532 external patients remaining. Eight internal cases were included with a total of 540 cases. RESULTS: From the 540 included cases, 384 patients (71.1%) had no UD compared to 156 patients (28.9%) with UD. Due to the anatomical ureteral course, the common iliac artery (CIA) was the most common vascular component of UVF, irrespective of the presence or absence of UD. Any dispute to whether the crossing point is the common or the external iliac artery (EIA) was settled for the CIA. Further common vascular components besides CIA include the aorta, EIA, internal iliac artery (IIA) including its branches and vascular bypasses including the anastomosis sites. Other unusual arterial localizations were stated under the "others" category. CONCLUSION: Identifying the location of the bleeding artery in UVF is critical and represents the most important step for successful management. We present the largest summary of described locations up to date including our own.

2.
JAMA Oncol ; 10(6): 755-764, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38722641

RESUMO

Importance: Studies with nivolumab, an approved therapy for metastatic urothelial carcinoma (mUC) after platinum-based chemotherapy, demonstrate improved outcomes with added high-dose ipilimumab. Objective: To assess efficacy and safety of a tailored approach using nivolumab + ipilimumab as an immunotherapeutic boost for mUC. Design, Setting, and Participants: In this phase 2 nonrandomized trial, patients with mUC composed 2 cohorts. Cohort 1 received first-line or second-/third-line nivolumab with escalating doses of ipilimumab, and cohort 2 received second-/third-line nivolumab with high-dose ipilimumab. Recruitment spanned 26 sites in Germany and Austria from August 8, 2017, to February 18, 2021. All patients had a 70% or higher Karnofsky Performance Score and measurable disease per Response Evaluation Criteria in Solid Tumours, version 1.1. Interventions: All patients initiated 4 doses of 240-mg nivolumab (1× every 2 wk). Week 8 nonresponders received nivolumab + ipilimumab (1× every 3 wk). Cohort 1 received 2 doses of 3-mg/kg nivolumab + 1-mg/kg ipilimumab followed by 2 doses of 1-mg/kg nivolumab + 3-mg/kg ipilimumab if no response. Due to safety concerns, cohort 1 treatment was halted, and first-line cohort 2 treatment was not pursued. Cohort 2 received 2 to 4 doses of 1-mg/kg nivolumab + 3-mg/kg ipilimumab. Responders continued with nivolumab maintenance but could receive nivolumab + ipilimumab for later progression. Main Outcomes and Measures: The primary end point was objective response rate. Results: The study comprised 169 patients (118 [69.8%] men; median [range] age, 68 [37-84] years): 86 in cohort 1 (42 first-line; 44 second-/third-line) and 83 in cohort 2. The median (IQR) follow-up times were 10.4 (4.2-23.5) months (first-line cohort 1), 7.5 (3.1-23.8) months (second-/third-line cohort 1), and 6.2 (3.2-22.7) months (cohort 2). Response rates to nivolumab induction were 12/42 (29%, first-line cohort 1), 10/44 (23%, second-/third-line cohort 1), and 17/83 (20%, cohort 2). Response rates to a tailored approach were 20/42 (48% [90% CI, 34%-61%], first-line cohort 1), 12/44 (27% [90% CI, 17%-40%], second-/third-line cohort 1), and 27/83 (33% [90% CI, 23%-42%], cohort 2). Three-year overall survival rates for first-line cohort 1, second-/third-line cohort 1, and cohort 2 using the Kaplan-Meier method were 32% (95% CI, 17%-49%), 19% (95% CI, 8%-33%), and 34% (95% CI, 23%-44%), respectively. Conclusions and Relevance: In this nonrandomized trial, although first-line cohort 1 treatment improved objective response rates, considerable progression events urge caution with this as a first-line therapy. Second-/third-line cohort 1 treatment did not improve response rates compared with nivolumab monotherapy. However, added high-dose ipilimumab may improve tumor response and survival in patients with mUC. Trial Registration: ClinicalTrials.gov Identifier: NCT03219775.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Ipilimumab , Nivolumabe , Humanos , Nivolumabe/uso terapêutico , Nivolumabe/administração & dosagem , Ipilimumab/uso terapêutico , Ipilimumab/administração & dosagem , Ipilimumab/efeitos adversos , Masculino , Idoso , Feminino , Pessoa de Meia-Idade , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Idoso de 80 Anos ou mais , Adulto , Neoplasias Urológicas/tratamento farmacológico , Neoplasias Urológicas/patologia , Neoplasias Urológicas/imunologia , Metástase Neoplásica , Carcinoma de Células de Transição/tratamento farmacológico , Carcinoma de Células de Transição/secundário , Carcinoma de Células de Transição/imunologia , Imunoterapia/métodos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/imunologia
3.
J Multidiscip Healthc ; 17: 1137-1145, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38500480

RESUMO

Purpose: The shortage of nursing staff as well as the slow progress in the German health care system's digitalisation has gained much attention due to COVID-19. Patient-specific medication management using the unit-dose dispensing system (UDDS) has the potential for a lasting and positive influence on both digitalisation and the relief of nursing staff. Methods: Nursing staff UDDS-acceptance was determined via a validated online survey. For the evaluation of stock keeping on the wards, the delivery quantities were determined for a comparative period before and after the introduction of the UDDS. The time required for on-ward medication-related processes on ward before and after the introduction of UDDS was recorded based on a survey form and the nursing relief in full-time equivalent (FTE) was calculated using the data obtained. Results: We show that nurses appreciate the UDDS and confirm a significant reduction in drug stocks on the wards. The UDDS reduces the time needed to dispense medications from 4.52 ± 0.35 min to 1.67 ± 0.15 min/day/patient. In relation to the entire medication process, this corresponds to a reduction of 50% per day and per patient. Based on 40,000 patients/year and a supply of 1,125 beds with unit-dose blisters, 7.36 FTE nursing staff can be relieved per year. In contrast, 6.5 FTE in the hospital pharmacy are required for supplying the hospitals. Conclusion: UDDS is well accepted by nurses, reduces stock levels on ward, and fulfils criteria as a nursing-relief measure.

4.
BJUI Compass ; 5(1): 90-100, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38179024

RESUMO

Objectives: Most renal tumours can be treated with a partial nephrectomy, with robot-assisted partial nephrectomy becoming the new gold standard. This procedure is challenging to learn in a live setting, especially the enucleation and renorraphy phases. In this study, we attempted to evaluate face, content, and preliminary construct validity of a 3D-printed silicone renal tumour model in robotic training for robot-assisted partial nephrectomy. Materials and Methods: We compared the operative results of three groups of surgeons with different experience levels (>20 partial nephrectomies, 1-20 partial nephrectomies and no experience at all) performing a robotic tumour excision of a newly developed silicone model with four embedded 3D-printed renal tumours. We evaluated the participants' performance using surgical margins, excision time, total preserved parenchyma, tumour injury and GEARS score (as assessed by two blinded experts) for construct validity. Postoperatively, the participants were asked to complete a survey to evaluate the usefulness, realism and difficulty of the model as a training and/or evaluation model. NASA-TLX scores were used to evaluate the operative workload. Results: Thirty-six participants were recruited, each group consisting of 10-14 participants. The operative performance was significantly better in the expert group as compared to the beginner group. NASA-TLX scores proved the model to be of an acceptable difficulty level.Expert group survey results showed an average score of 6.3/10 on realism of the model, 8.2/10 on the usefulness as training model and 6.9/10 score on the usefulness as an evaluation tool. GEARS scores showed a non-significant tendency to improve between trials, emphasizing its potential as a training model. Conclusion: Face and content validity of our 3D renal tumour model were demonstrated. The vast majority of participants found the model realistic and useful for training and for evaluation. To evaluate construct and predictive validity, we require further research, aiming to compare the results of 3D-model trained surgeons with those of untrained surgeons in real-life surgery.

5.
Sci Rep ; 14(1): 2282, 2024 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-38280916

RESUMO

Research on the plastic contamination of organic fertilizer (compost) has largely concentrated on particles and fragments > 1 mm. Small, submillimeter microplastic particles may be more hazardous to the environment. However, research on their presence in composts has been impeded by the difficulty to univocally identify small plastic particles in such complex matrices. Here a method is proposed for the analysis of particles between 0.01 and 1.0 mm according to number, size, and polymer type in compost. As a first demonstration of its potential, the method is used to determine large and small microplastic in composts from eight municipal compost producing plants: three simple biowaste composters, four plants processing greenery and cuttings and one two-stage biowaste digester-composter. While polyethylene, PE, tends to dominate among fragments > 1 mm, the microplastic fraction contained more polypropylene, PP. Whereas the contamination with PE/PP microplastic was similar over the investigated composts, only composts prepared from biowaste contained microplastic with a signature of biodegradable plastic, namely poly(butylene adipate co-terephthalate), PBAT. Moreover, in these composts PBAT microplastic tended to form the largest fraction. When the bulk of residual PBAT in the composts was analyzed by chloroform extraction, an inverse correlation between the number of particles > 0.01 mm and the total extracted amount was seen, arguing for breakdown into smaller particles, but not necessarily a mass reduction. PBAT oligomers and monomers as possible substrates for subsequent biodegradation were not found. Remaining microplastic will enter the environment with the composts, where its subsequent degradability depends on the local conditions and is to date largely uninvestigated.


Assuntos
Compostagem , Plásticos , Plásticos/análise , Microplásticos , Polímeros , Polipropilenos
6.
Urologie ; 63(1): 67-74, 2024 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-37747493

RESUMO

BACKGROUND: In addition to erectile dysfunction, urinary incontinence is the most common functional limitation after radical prostatectomy (RPE) for prostate cancer (PCa). The German S3 guideline recommends informing patients about possible effects of the therapy options, including incontinence. However, only little data on continence from routine care in German-speaking countries after RPE are currently available, which makes it difficult to inform patients. OBJECTIVE: The aim of this work is to present data on the frequency and severity of urinary incontinence after RPE from routine care. MATERIALS AND METHODS: Information from the PCO (Prostate Cancer Outcomes) study is used, which was collected between 2016 and 2022 in 125 German Cancer Society (DKG)-certified prostate cancer centers in 17,149 patients using the Expanded Prostate Cancer Index Composite Short Form (EPIC-26). Changes in the "incontinence" score before (T0) and 12 months after RPE (T1) and the proportion of patients who used pads, stratified by age and risk group, are reported. RESULTS: The average score for urinary incontinence (value range: 0-worst possible to 100-best possible) was 93 points at T0 and 73 points 12 months later. At T0, 97% of the patients did not use a pad, compared to 56% at T1. 43% of the patients who did not use a pad before surgery used at least one pad a day 12 months later, while 13% use two or more. The proportion of patients using pads differs by age and risk classification. CONCLUSION: The results provide a comprehensive insight into functional outcome 12 months after RPE and can be taken into account when informing patients.


Assuntos
Disfunção Erétil , Neoplasias da Próstata , Incontinência Urinária , Masculino , Humanos , Incontinência Urinária/epidemiologia , Disfunção Erétil/epidemiologia , Neoplasias da Próstata/cirurgia , Prostatectomia/efeitos adversos
7.
Eur Urol ; 84(6): 571-578, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37758574

RESUMO

BACKGROUND: The role of immune checkpoint inhibitor (ICI) maintenance therapy in metastatic renal cell carcinoma (mRCC) is undefined. OBJECTIVE: To determine whether switch maintenance therapy with nivolumab improves clinical outcomes in patients with mRCC with tyrosine kinase inhibitor (TKI) sensitivity. DESIGN, SETTING, AND PARTICIPANTS: This open-label phase 2 trial randomized patients with a partial response or stable disease after 10-12-wk TKI induction therapy to either TKI or nivolumab maintenance. Key inclusion criteria were measurable disease, clear cell histology, Eastern Cooperative Oncology Group performance status (ECOG PS) 0-2, and adequate organ function. INTERVENTION: Intravenous nivolumab 8 × 240 mg every 2 wk, followed by 480 mg every 4 wk or sunitinib 50 mg (4-2 regimen) or pazopanib 800 mg once daily orally. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSES: The primary endpoint was overall survival (OS). Secondary endpoints were the objective response rate (ORR; Response Evaluation Criteria in Solid Tumors v1.1), progression-free survival (PFS), safety (Common Terminology Criteria for Adverse Events v4.03), and patient-reported outcomes (Functional Assessment of Cancer Therapy Kidney Symptom Index). The Kaplan-Meier method, two-sided log-rank tests, and Cox regression models were used for statistical analysis. RESULTS AND LIMITATIONS: Maintenance therapy was nivolumab for 25 patients (51.0%) and TKI for 24 (48.9%). The median age was 65 yr (range 35-79). Nine patients (18.4%) were female, 31 (63.3%) had ECOG PS of 0, and 15 (30.6%) had favorable risk. OS data are immature (17 deaths, 34.7%). The ORR was 20.0% (n = 5) for nivolumab and 52.2% (n = 12) for TKI. PFS was worse with nivolumab (hazard ratio 2.57, 95% confidence interval 1.36-4.89; p = 0.003). Grade ≥3 adverse events occurred in 14 patients (56.0%) with nivolumab and 17 (70.8%) with TKI. A major limitation is early termination of our study. CONCLUSIONS: TKI treatment achieved superior ORR and PFS in comparison to nivolumab maintenance therapy. Our data do not indicate a role for nivolumab switch maintenance in mRCC. PATIENT SUMMARY: Patients with metastatic kidney cancer who experienced a tumor response or disease stabilization after a short period of targeted treatment with a tyrosine kinase inhibitor did not benefit from a switch to the immunotherapy drug nivolumab. Patients who continued their original treatment achieved better responses and a longer time without disease progression. This trial is registered on EudraCT as 2016-002170-13 and on ClinicalTrials.gov as NCT02959554.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Idoso , Feminino , Humanos , Masculino , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Nivolumabe/efeitos adversos , Inibidores de Proteínas Quinases/efeitos adversos , Adulto , Pessoa de Meia-Idade
8.
Scand J Med Sci Sports ; 33(12): 2482-2498, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37635277

RESUMO

PURPOSE: Laboratory tests are commonly performed by cross-country (XC) skiers due to the challenges of obtaining reliable performance indicators on snow. However, only a few studies have reported reliability data for ski-specific test protocols. Therefore, this study examined the test-retest reliability of ski-specific aerobic, sprint, and neuromuscular performance tests. METHODS: Thirty-nine highly trained XC skiers (26 men and 13 women, age: 22 ± 4 years, V̇O2max : 70.1 ± 4.5 and 58.8 ± 4.4 mL·kg-1 ·min-1 , respectively) performed two test trials within 6 days of a diagonal V̇O2max test, n = 27; skating graded exercise test to assess the second lactate threshold (LT2 ), n = 27; 24-min double poling time trial (24-min DP, n = 25), double poling sprint test (SprintDP1 , n = 27), and 1-min self-paced skating sprint test (Sprint1-min , n = 26) using roller skis on a treadmill, and an upper-body strength test (UB-ST, n = 27) to assess peak power (Ppeak ) with light, medium, and heavy loads. For each test, the coefficient of variation (CV), intraclass correlation coefficient (ICC), and minimal detectable change (MDC) were calculated. RESULTS: V̇O2max demonstrated good-to-excellent reliability (CV = 1.4%; ICC = 0.99; MDC = 112 mL·min-1 ), whereas moderate-to-excellent reliability was found for LT2 (CV = 3.1%; ICC = 0.95). Performance during 24-min DP, SprintDP1 , and Sprint1-min showed good-to-excellent reliability (CV = 1.0%-2.3%; ICC = 0.96-0.99). Absolute reliability for UB-ST Ppeak was poor (CV = 4.9%-7.8%), while relative reliability was excellent (ICC = 0.93-0.97) across the loads. CONCLUSION: In highly trained XC skiers, sport-specific aerobic and sprint performance tests demonstrated high test-retest reliability, while neuromuscular performance for the upper body was less reliable. Using the presented protocols, practitioners can assess within- and between-season changes in relevant performance indicators.


Assuntos
Desempenho Atlético , Esqui , Masculino , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Reprodutibilidade dos Testes , Teste de Esforço , Ácido Láctico , Força Muscular , Consumo de Oxigênio
9.
Elife ; 122023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37158597

RESUMO

The amoeba-resistant bacterium Legionella pneumophila causes Legionnaires' disease and employs a type IV secretion system (T4SS) to replicate in the unique, ER-associated Legionella-containing vacuole (LCV). The large fusion GTPase Sey1/atlastin is implicated in ER dynamics, ER-derived lipid droplet (LD) formation, and LCV maturation. Here, we employ cryo-electron tomography, confocal microscopy, proteomics, and isotopologue profiling to analyze LCV-LD interactions in the genetically tractable amoeba Dictyostelium discoideum. Dually fluorescence-labeled D. discoideum producing LCV and LD markers revealed that Sey1 as well as the L. pneumophila T4SS and the Ran GTPase activator LegG1 promote LCV-LD interactions. In vitro reconstitution using purified LCVs and LDs from parental or Δsey1 mutant D. discoideum indicated that Sey1 and GTP promote this process. Sey1 and the L. pneumophila fatty acid transporter FadL were implicated in palmitate catabolism and palmitate-dependent intracellular growth. Taken together, our results reveal that Sey1 and LegG1 mediate LD- and FadL-dependent fatty acid metabolism of intracellular L. pneumophila.


Assuntos
Dictyostelium , Legionella pneumophila , Legionella , Doença dos Legionários , Humanos , Legionella pneumophila/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Macrófagos/metabolismo , Dictyostelium/metabolismo , Gotículas Lipídicas/metabolismo , Vacúolos/metabolismo , Legionella/metabolismo , Doença dos Legionários/microbiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
10.
Cell Chem Biol ; 30(5): 499-512.e5, 2023 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-37100053

RESUMO

Respiratory complex I is a multicomponent enzyme conserved between eukaryotic cells and many bacteria, which couples oxidation of electron donors and quinone reduction with proton pumping. Here, we report that protein transport via the Cag type IV secretion system, a major virulence factor of the Gram-negative bacterial pathogen Helicobacter pylori, is efficiently impeded by respiratory inhibition. Mitochondrial complex I inhibitors, including well-established insecticidal compounds, selectively kill H. pylori, while other Gram-negative or Gram-positive bacteria, such as the close relative Campylobacter jejuni or representative gut microbiota species, are not affected. Using a combination of different phenotypic assays, selection of resistance-inducing mutations, and molecular modeling approaches, we demonstrate that the unique composition of the H. pylori complex I quinone-binding pocket is the basis for this hypersensitivity. Comprehensive targeted mutagenesis and compound optimization studies highlight the potential to develop complex I inhibitors as narrow-spectrum antimicrobial agents against this pathogen.


Assuntos
Helicobacter pylori , Humanos , Helicobacter pylori/genética , Helicobacter pylori/metabolismo , Complexo I de Transporte de Elétrons/genética , Complexo I de Transporte de Elétrons/metabolismo , Mutagênese , Mutação , Oxirredução , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
11.
mBio ; 14(1): e0309322, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36598194

RESUMO

Small bacterial regulatory RNAs (sRNAs) have been implicated in the regulation of numerous metabolic pathways. In most of these studies, sRNA-dependent regulation of mRNAs or proteins of enzymes in metabolic pathways has been predicted to affect the metabolism of these bacteria. However, only in a very few cases has the role in metabolism been demonstrated. Here, we performed a combined transcriptome and metabolome analysis to define the regulon of the sibling sRNAs NgncR_162 and NgncR_163 (NgncR_162/163) and their impact on the metabolism of Neisseria gonorrhoeae. These sRNAs have been reported to control genes of the citric acid and methylcitric acid cycles by posttranscriptional negative regulation. By transcriptome analysis, we now expand the NgncR_162/163 regulon by several new members and provide evidence that the sibling sRNAs act as both negative and positive regulators of target gene expression. Newly identified NgncR_162/163 targets are mostly involved in transport processes, especially in the uptake of glycine, phenylalanine, and branched-chain amino acids. NgncR_162/163 also play key roles in the control of serine-glycine metabolism and, hence, probably affect biosyntheses of nucleotides, vitamins, and other amino acids via the supply of one-carbon (C1) units. Indeed, these roles were confirmed by metabolomics and metabolic flux analysis, which revealed a bipartite metabolic network with glucose degradation for the supply of anabolic pathways and the usage of amino acids via the citric acid cycle for energy metabolism. Thus, by combined deep RNA sequencing (RNA-seq) and metabolomics, we significantly extended the regulon of NgncR_162/163 and demonstrated the role of NgncR_162/163 in the regulation of central metabolic pathways of the gonococcus. IMPORTANCE Neisseria gonorrhoeae is a major human pathogen which infects more than 100 million people every year. An alarming development is the emergence of gonococcal strains that are resistant against virtually all antibiotics used for their treatment. Despite the medical importance and the vanishing treatment options of gonococcal infections, the bacterial metabolism and its regulation have been only weakly defined until today. Using RNA-seq, metabolomics, and 13C-guided metabolic flux analysis, we here investigated the gonococcal metabolism and its regulation by the previously studied sibling sRNAs NgncR_162/163. The results demonstrate the regulation of transport processes and metabolic pathways involved in the biosynthesis of nucleotides, vitamins, and amino acids by NgncR_162/163. In particular, the combination of transcriptome and metabolic flux analyses provides a heretofore unreached depth of understanding the core metabolic pathways and their regulation by the neisserial sibling sRNAs. This integrative approach may therefore also be suitable for the functional analysis of a growing number of other bacterial metabolic sRNA regulators.


Assuntos
Neisseria gonorrhoeae , Pequeno RNA não Traduzido , Humanos , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/metabolismo , Irmãos , Bactérias/genética , Redes e Vias Metabólicas/genética , RNA Bacteriano/metabolismo , Pequeno RNA não Traduzido/genética , Pequeno RNA não Traduzido/metabolismo , Nucleotídeos/metabolismo , Aminoácidos/metabolismo , Vitaminas , Regulação Bacteriana da Expressão Gênica
12.
Front Sports Act Living ; 4: 966203, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36406769

RESUMO

Introduction: When exercising in the cold, optimizing thermoregulation is essential to maintain performance. However, no study has investigated thermal parameters with wearable-based measurements in a field setting among elite Nordic skiers. Therefore, this study aimed to assess the thermal response and sensation measured at different body parts during exercise in a cold environment in biathletes. Methods: Thirteen Swiss national team biathletes (6 females, 7 males) performed two skiing bouts in the skating technique on two consecutive days (ambient temperature: -3.74 ± 2.32 °C) at 78 ± 4% of maximal heart rate. Heat flux (HF), core (Tcore) and skin (Tskin) temperature were measured with sensors placed on the thigh, back, anterior and lateral thorax. Thermal sensation (TS) was assessed three times for different body parts: in protective winter clothing, in a race suit before (PRE) and after exercise (POST). Results: HF demonstrated differences (p < 0.001) between sensor locations, with the thigh showing the highest heat loss (344 ± 37 kJ/m2), followed by the back (269 ± 6 kJ/m2), the lateral thorax (220 ± 47 kJ/m2), and the anterior thorax (192 ± 37 kJ/m2). Tcore increased (p < 0.001). Tskin decreased for all body parts (p < 0.001). Thigh Tskin decreased more than for other body parts (p < 0.001). From PRE to POST, TS of the hands decreased (p < 0.01). Conclusion: Biathletes skiing in a race suit at moderate intensity experience significant heat loss and a large drop in Tskin, particularly at the quadriceps muscle. To support the optimal functioning of working muscles, body-part dependent differences in the thermal response should be considered for clothing strategy and for race suit design.

13.
Scand J Clin Lab Invest ; 82(6): 474-480, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36129418

RESUMO

Recently, a new automated carbon monoxide (CO) rebreathing method (aCO) to estimate haemoglobin mass (Hbmass) was introduced. The aCO method uses the same CO dilution principle as the widely used optimised CO rebreathing method (oCO). The two methods differ in terms of CO administration, body position, and rebreathing time. Whereas with aCO, CO is administered automatically by the system in a supine position of the subject, with oCO, CO is administered manually by an experienced operator with the subject sitting. Therefore, the aim of this study was to quantify possible differences in Hbmass estimated with the two methods. Hbmass was estimated in 18 subjects (9 females, 9 males) with oCO using capillary blood samples (oCOc) and aCO taking simultaneously venous blood samples (aCOv) and capillary blood samples (aCOc). Overall, Hbmass was different between the three measurement procedures (F = 57.55, p < .001). Hbmass was lower (p < .001) for oCOc (737 g ± 179 g) than for both aCOv (825 g ± 189 g, -9.3%) and aCOc (835 g ± 189 g, -10.6%). There was no difference in Hbmass estimated with aCOv and aCOc procedures (p = .12). Three factors can likely explain the 10% difference in Hbmass: differences in calculations (including a factor for myoglobin flux), body position (distribution of CO in blood circulation) during rebreathing, and time of blood sampling. Moreover, the determination of Hbmass with aCO is possible with capillary blood sampling instead of venous blood sampling.


Assuntos
Monóxido de Carbono , Mioglobina , Coleta de Amostras Sanguíneas , Feminino , Hemoglobinas/análise , Humanos , Masculino , Flebotomia
14.
Sci Rep ; 12(1): 9021, 2022 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-35637211

RESUMO

Biodegradable plastics (BDP) are expected to mineralize easily, in particular under conditions of technical composting. However, the complexity of the sample matrix has largely prevented degradation studies under realistic conditions. Here composts and fertilizers from state-of-the-art municipal combined anaerobic/aerobic biowaste treatment plants were investigated for residues of BDP. We found BDP fragments > 1 mm in significant numbers in the final composts intended as fertilizer for agriculture and gardening. Compared to pristine compostable bags, the recovered BDP fragments showed differences in their material properties, which potentially renders them less prone to further biodegradation. BDP fragments < 1 mm were extracted in bulk and came up to 0.43 wt% of compost dry weight. Finally, the liquid fertilizer produced during the anaerobic treatment contained several thousand BDP fragments < 500 µm per liter. Hence, our study questions, if currently available BDP are compatible with applications in areas of environmental relevance, such as fertilizer production.


Assuntos
Plásticos Biodegradáveis , Compostagem , Agricultura , Biodegradação Ambiental , Fertilizantes
15.
Bio Protoc ; 12(6): e4364, 2022 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-35434198

RESUMO

Different pathways for autotrophic CO2 fixation can be recognized by the presence of genes for their specific key enzymes. On this basis, (meta)genomic, (meta)transcriptomic, or (meta)proteomic analysis enables the identification of the role of an organism or a distinct pathway in primary production. However, the recently discovered variant of the reductive tricarboxylic acid (rTCA) cycle, the reverse oxidative tricarboxylic acid (roTCA) cycle, lacks unique enzymes, a feature that makes it cryptic for bioinformatics analysis. This pathway is a reversal of the widespread tricarboxylic acid (TCA) cycle. The functioning of the roTCA cycle requires unusually high activity of citrate synthase, the enzyme responsible for citrate cleavage, as well as elevated CO2 partial pressures. Here, we present a detailed description of the protocol we used for the identification of the roTCA cycle in members of Desulfurellaceae. First, we describe the anaerobic cultivation of Desulfurellaceae at different CO2 concentrations with a method that can be adapted to the cultivation of other anaerobes. Then, we explain how to measure activities of enzymes responsible for citrate cleavage, malate dehydrogenase reaction, and the crucial carboxylation step of the cycle catalyzed by pyruvate synthase in cell extracts. In conclusion, we describe stable isotope experiments that allow tracking of the roTCA cycle in vivo, through the position-specific incorporation of carbon-13 into amino acids. The label is provided to the organism as 13CO2 or [1-13C]glutamate. The same key methodology can be used for the reliable evaluation of the functioning of the roTCA cycle in any organism under study. This pathway is likely to participate, completely unseen, in the metabolism of various microorganisms. Graphic abstract.

16.
Cell Rep ; 37(6): 109989, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34758302

RESUMO

Mutations in mitochondrial genes impairing energy production cause mitochondrial diseases (MDs), and clinical studies have shown that MD patients are prone to bacterial infections. However, the relationship between mitochondrial (dys)function and infection remains largely unexplored, especially in epithelial cells, the first barrier to many pathogens. Here, we generate an epithelial cell model for one of the most common mitochondrial diseases, Leigh syndrome, by deleting surfeit locus protein 1 (SURF1), an assembly factor for respiratory chain complex IV. We use this genetic model and a complementary, nutrient-based approach to modulate mitochondrial respiration rates and show that impaired mitochondrial respiration favors entry of the human pathogen Listeria monocytogenes, a well-established bacterial infection model. Reversely, enhanced mitochondrial energy metabolism decreases infection efficiency. We further demonstrate that endocytic recycling is reduced in mitochondrial respiration-dependent cells, dampening L. monocytogenes infection by slowing the recycling of its host cell receptor c-Met, highlighting a previously undescribed role of mitochondrial respiration during infection.


Assuntos
Neoplasias do Colo/microbiologia , Listeria monocytogenes/fisiologia , Listeriose/prevenção & controle , Proteínas de Membrana/metabolismo , Mitocôndrias/fisiologia , Proteínas Mitocondriais/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Respiração , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Metabolismo Energético , Células HCT116 , Humanos , Listeriose/microbiologia , Proteínas de Membrana/genética , Proteínas Mitocondriais/genética , Proteínas Proto-Oncogênicas c-met/genética
17.
Mol Microbiol ; 116(3): 841-860, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34164854

RESUMO

Helicobacter pylori displays a worldwide infection rate of about 50%. The Gram-negative bacterium is the main reason for gastric cancer and other severe diseases. Despite considerable knowledge about the metabolic inventory of H. pylori, carbon fluxes through the citrate cycle (TCA cycle) remained enigmatic. In this study, different 13 C-labeled substrates were supplied as carbon sources to H. pylori during microaerophilic growth in a complex medium. After growth, 13 C-excess and 13 C-distribution were determined in multiple metabolites using GC-MS analysis. [U-13 C6 ]Glucose was efficiently converted into glyceraldehyde but only less into TCA cycle-related metabolites. In contrast, [U-13 C5 ]glutamate, [U-13 C4 ]succinate, and [U-13 C4 ]aspartate were incorporated at high levels into intermediates of the TCA cycle. The comparative analysis of the 13 C-distributions indicated an adaptive TCA cycle fully operating in the closed oxidative direction with rapid equilibrium fluxes between oxaloacetate-succinate and α-ketoglutarate-citrate. 13 C-Profiles of the four-carbon intermediates in the TCA cycle, especially of malate, together with the observation of an isocitrate lyase activity by in vitro assays, suggested carbon fluxes via a glyoxylate bypass. In conjunction with the lack of enzymes for anaplerotic CO2 fixation, the glyoxylate bypass could be relevant to fill up the TCA cycle with carbon atoms derived from acetyl-CoA.


Assuntos
Aminoácidos/metabolismo , Ciclo do Carbono , Carbono/metabolismo , Ácido Cítrico/metabolismo , Glucose/metabolismo , Helicobacter pylori/metabolismo , Acetilcoenzima A/metabolismo , Ácido Aspártico/metabolismo , Metabolismo dos Carboidratos , Ciclo do Ácido Cítrico , Ácido Glutâmico/metabolismo , Gliceraldeído/metabolismo , Glioxilatos/metabolismo , Infecções por Helicobacter/microbiologia , Humanos , Malatos/metabolismo , Redes e Vias Metabólicas , Ácido Succínico/metabolismo
18.
Front Sports Act Living ; 3: 580486, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33791598

RESUMO

We recently measured the development of hemoglobin mass (Hbmass) in 10 Swiss national team endurance athletes between ages 16-19. Level of Hbmass at age 16 was an important predictor for Hbmass and endurance performance at age 19. The aim was to determine how many of these young athletes were still members of Swiss national teams (NT) at age 25, how many already terminated their career (TC), and whether Hbmass at ages 16 and 19 was different between the NT and TC group. We measured Hbmass using the optimized carbon monoxide re-breathing technique in 10 high-performing endurance athletes every 0.5 years beginning at age 16 and ending at age 19. At age 25, two athletes were in the NT group and eight athletes in the TC group. Mean absolute, body weight-, and lean body mass (LBM) related Hbmass at age 16 was 833 ± 61 g, 13.7 ± 0.2 g/kg and 14.2 ± 0.2 g/kg LBM in the NT group and 742 ± 83 g, 12.2 ± 0.7 g/kg and 12.8 ± 0.8 g/kg LBM in the TC group. At age 19, Hbmass was 1,042 ± 89 g, 14.6 ± 0.2 g/kg and 15.4 ± 0.2 g/kg LBM in the NT group and 863 ± 109 g, 12.7 ± 1.1 g/kg and 13.5 ± 1.1 g/kg LBM in the TC group. Body weight- and LBM related Hbmass were higher in the NT group than in the TC group at ages 16 and 19 (p < 0.05). These results indicate, that Hbmass at ages 16 and 19 possibly could be an important predictor for later national team membership in endurance disciplines.

19.
Int J Med Microbiol ; 311(4): 151504, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33906075

RESUMO

The metabolism of Legionella pneumophila strain Paris was elucidated during different time intervals of growth within its natural host Acanthamoeba castellanii. For this purpose, the amoebae were supplied after bacterial infection (t =0 h) with 11 mM [U-13C6]glucose or 3 mM [U-13C3]serine, respectively, during 0-17 h, 17-25 h, or 25-27 h of incubation. At the end of these time intervals, bacterial and amoebal fractions were separated. Each of these fractions was hydrolyzed under acidic conditions. 13C-Enrichments and isotopologue distributions of resulting amino acids and 3-hydroxybutyrate were determined by gas chromatography - mass spectrometry. Comparative analysis of the labelling patterns revealed the substrate preferences, metabolic pathways, and relative carbon fluxes of the intracellular bacteria and their amoebal host during the time course of the infection cycle. Generally, the bacterial infection increased the usage of exogenous glucose via glycolysis by A. castellanii. In contrast, carbon fluxes via the amoebal citrate cycle were not affected. During the whole infection cycle, intracellular L. pneumophila incorporated amino acids from their host into the bacterial proteins. However, partial bacterial de novo biosynthesis from exogenous 13C-Ser and, at minor rates, from 13C-glucose could be shown for bacterial Ala, Asp, Glu, and Gly. More specifically, the catabolic usage of Ser increased during the post-exponential phase of intracellular growth, whereas glucose was utilized by the bacteria throughout the infection cycle and not only late during infection as assumed on the basis of earlier in vitro experiments. The early usage of 13C-glucose by the intracellular bacteria suggests that glucose availability could serve as a trigger for replication of L. pneumophila inside the vacuoles of host cells.


Assuntos
Acanthamoeba castellanii , Legionella pneumophila , Aminoácidos/metabolismo , Proteínas de Bactérias/metabolismo , Legionella pneumophila/metabolismo , Redes e Vias Metabólicas
20.
Nature ; 592(7856): 784-788, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33883741

RESUMO

It has recently been shown that in anaerobic microorganisms the tricarboxylic acid (TCA) cycle, including the seemingly irreversible citrate synthase reaction, can be reversed and used for autotrophic fixation of carbon1,2. This reversed oxidative TCA cycle requires ferredoxin-dependent 2-oxoglutarate synthase instead of the NAD-dependent dehydrogenase as well as extremely high levels of citrate synthase (more than 7% of the proteins in the cell). In this pathway, citrate synthase replaces ATP-citrate lyase of the reductive TCA cycle, which leads to the spending of one ATP-equivalent less per one turn of the cycle. Here we show, using the thermophilic sulfur-reducing deltaproteobacterium Hippea maritima, that this route is driven by high partial pressures of CO2. These high partial pressures are especially important for the removal of the product acetyl coenzyme A (acetyl-CoA) through reductive carboxylation to pyruvate, which is catalysed by pyruvate synthase. The reversed oxidative TCA cycle may have been functioning in autotrophic CO2 fixation in a primordial atmosphere that is assumed to have been rich in CO2.


Assuntos
Processos Autotróficos , Dióxido de Carbono/química , Ciclo do Ácido Cítrico , Deltaproteobacteria/enzimologia , ATP Citrato (pro-S)-Liase/metabolismo , Acetilcoenzima A/metabolismo , Proteínas de Bactérias/metabolismo , Carbono/metabolismo , Deltaproteobacteria/crescimento & desenvolvimento , Pressão Parcial , Ácido Pirúvico/metabolismo
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