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1.
N Engl J Med ; 387(16): 1456-1466, 2022 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-36027564

RESUMO

BACKGROUND: Evidence to support the choice of blood-pressure targets for the treatment of comatose survivors of out-of-hospital cardiac arrest who are receiving intensive care is limited. METHODS: In a double-blind, randomized trial with a 2-by-2 factorial design, we evaluated a mean arterial blood-pressure target of 63 mm Hg as compared with 77 mm Hg in comatose adults who had been resuscitated after an out-of-hospital cardiac arrest of presumed cardiac cause; patients were also assigned to one of two oxygen targets (reported separately). The primary outcome was a composite of death from any cause or hospital discharge with a Cerebral Performance Category (CPC) of 3 or 4 within 90 days (range, 0 to 5, with higher categories indicating more severe disability; a category of 3 or 4 indicates severe disability or coma). Secondary outcomes included neuron-specific enolase levels at 48 hours, death from any cause, scores on the Montreal Cognitive Assessment (range, 0 to 30, with higher scores indicating better cognitive ability) and the modified Rankin scale (range, 0 to 6, with higher scores indicating greater disability) at 3 months, and the CPC at 3 months. RESULTS: A total of 789 patients were included in the analysis (393 in the high-target group and 396 in the low-target group). A primary-outcome event occurred in 133 patients (34%) in the high-target group and in 127 patients (32%) in the low-target group (hazard ratio, 1.08; 95% confidence interval [CI], 0.84 to 1.37; P = 0.56). At 90 days, 122 patients (31%) in the high-target group and 114 patients (29%) in the low-target group had died (hazard ratio, 1.13; 95% CI, 0.88 to 1.46). The median CPC was 1 (interquartile range, 1 to 5) in both the high-target group and the low-target group; the corresponding median modified Rankin scale scores were 1 (interquartile range, 0 to 6) and 1 (interquartile range, 0 to 6), and the corresponding median Montreal Cognitive Assessment scores were 27 (interquartile range, 24 to 29) and 26 (interquartile range, 24 to 29). The median neuron-specific enolase level at 48 hours was also similar in the two groups. The percentages of patients with adverse events did not differ significantly between the groups. CONCLUSIONS: Targeting a mean arterial blood pressure of 77 mm Hg or 63 mm Hg in patients who had been resuscitated from cardiac arrest did not result in significantly different percentages of patients dying or having severe disability or coma. (Funded by the Novo Nordisk Foundation; BOX ClinicalTrials.gov number, NCT03141099.).


Assuntos
Pressão Arterial , Coma , Parada Cardíaca Extra-Hospitalar , Adulto , Humanos , Pressão Arterial/fisiologia , Biomarcadores/análise , Reanimação Cardiopulmonar , Coma/diagnóstico , Coma/etiologia , Coma/mortalidade , Coma/fisiopatologia , Método Duplo-Cego , Indicadores Básicos de Saúde , Parada Cardíaca Extra-Hospitalar/complicações , Parada Cardíaca Extra-Hospitalar/terapia , Oxigênio , Fosfopiruvato Hidratase/análise , Sobreviventes , Cuidados Críticos
2.
Mol Cell Proteomics ; 22(3): 100508, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36787876

RESUMO

White adipose tissue is deposited mainly as subcutaneous adipose tissue (SAT), often associated with metabolic protection, and abdominal/visceral adipose tissue, which contributes to metabolic disease. To investigate the molecular underpinnings of these differences, we conducted comprehensive proteomics profiling of whole tissue and isolated adipocytes from these two depots across two diets from C57Bl/6J mice. The adipocyte proteomes from lean mice were highly conserved between depots, with the major depot-specific differences encoded by just 3% of the proteome. Adipocytes from SAT (SAdi) were enriched in pathways related to mitochondrial complex I and beiging, whereas visceral adipocytes (VAdi) were enriched in structural proteins and positive regulators of mTOR presumably to promote nutrient storage and cellular expansion. This indicates that SAdi are geared toward higher catabolic activity, while VAdi are more suited for lipid storage. By comparing adipocytes from mice fed chow or Western diet (WD), we define a core adaptive proteomics signature consisting of increased extracellular matrix proteins and decreased fatty acid metabolism and mitochondrial Coenzyme Q biosynthesis. Relative to SAdi, VAdi displayed greater changes with WD including a pronounced decrease in mitochondrial proteins concomitant with upregulation of apoptotic signaling and decreased mitophagy, indicating pervasive mitochondrial stress. Furthermore, WD caused a reduction in lipid handling and glucose uptake pathways particularly in VAdi, consistent with adipocyte de-differentiation. By overlaying the proteomics changes with diet in whole adipose tissue and isolated adipocytes, we uncovered concordance between adipocytes and tissue only in the visceral adipose tissue, indicating a unique tissue-specific adaptation to sustained WD in SAT. Finally, an in-depth comparison of isolated adipocytes and 3T3-L1 proteomes revealed a high degree of overlap, supporting the utility of the 3T3-L1 adipocyte model. These deep proteomes provide an invaluable resource highlighting differences between white adipose depots that may fine-tune their unique functions and adaptation to an obesogenic environment.


Assuntos
Tecido Adiposo , Proteoma , Camundongos , Animais , Proteoma/metabolismo , Tecido Adiposo Branco , Adipócitos/metabolismo , Lipídeos
3.
Am J Physiol Endocrinol Metab ; 326(5): E663-E672, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568150

RESUMO

Despite the fact that genes and the environment are known to play a central role in islet function, our knowledge of how these parameters interact to modulate insulin secretory function remains relatively poor. Presently, we performed ex vivo glucose-stimulated insulin secretion and insulin content assays in islets of 213 mice from 13 inbred mouse strains on chow, Western diet (WD), and a high-fat, carbohydrate-free (KETO) diet. Strikingly, among these 13 strains, islets from the commonly used C57BL/6J mouse strain were the least glucose responsive. Using matched metabolic phenotyping data, we performed correlation analyses of isolated islet parameters and found a positive correlation between basal and glucose-stimulated insulin secretion, but no relationship between insulin secretion and insulin content. Using in vivo metabolic measures, we found that glucose tolerance determines the relationship between ex vivo islet insulin secretion and plasma insulin levels. Finally, we showed that islet glucose-stimulated insulin secretion decreased with KETO in almost all strains, concomitant with broader phenotypic changes, such as increased adiposity and glucose intolerance. This is an important finding as it should caution against the application of KETO diet for beta-cell health. Together these data offer key insights into the intersection of diet and genetic background on islet function and whole body glucose metabolism.NEW & NOTEWORTHY Thirteen strains of mice on chow, Western diet, and high-fat, carbohydrate-free (KETO), correlating whole body phenotypes to ex vivo pancreatic islet functional measurements, were used. The study finds a huge spectrum of functional islet responses and insulin phenotypes across all strains and diets, with the ubiquitous C57Bl/6J mouse exhibiting the lowest secretory response of all strains, highlighting the overall importance of considering genetic background when investigating islet function. Ex vivo basal and stimulated insulin secretion are correlated in the islet, and KETO imparts widescale downregulation of islet insulin secretion.


Assuntos
Dieta Hiperlipídica , Secreção de Insulina , Insulina , Ilhotas Pancreáticas , Camundongos Endogâmicos C57BL , Animais , Camundongos , Ilhotas Pancreáticas/metabolismo , Secreção de Insulina/fisiologia , Insulina/metabolismo , Insulina/sangue , Masculino , Dieta Ocidental , Glucose/metabolismo , Dieta com Restrição de Carboidratos , Camundongos Endogâmicos , Glicemia/metabolismo , Intolerância à Glucose/metabolismo , Intolerância à Glucose/genética
4.
Int J Obes (Lond) ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961153

RESUMO

BACKGROUND: Weight loss can improve the metabolic complications of obesity. However, it is unclear whether insulin resistance persists despite weight loss and whether any protective benefits are preserved following weight regain (weight cycling). The impact of genetic background on weight cycling is undocumented. We aimed to investigate the effects of weight loss and weight cycling on metabolic outcomes and sought to clarify the role of genetics in this relationship. METHOD: Both C57BL/6 J and genetically heterogeneous Diversity Outbred Australia (DOz) mice were alternately fed high fat Western-style diet (WD) and a chow diet at 8-week intervals. Metabolic measures including body composition, glucose tolerance, pancreatic beta cell activity, liver lipid levels and adipose tissue insulin sensitivity were determined. RESULTS: After diet switch from WD (8-week) to chow (8-week), C57BL/6 J mice displayed a rapid normalisation of body weight, adiposity, hyperinsulinemia, liver lipid levels and glucose uptake into adipose tissue comparable to chow-fed controls. In response to the same dietary intervention, genetically diverse DOz mice conversely maintained significantly higher fat mass and insulin levels compared to chow-fed controls and exhibited much more profound interindividual variability than C57BL/6 J mice. Weight cycled (WC) animals were re-exposed to WD (8-week) and compared to age-matched controls fed 8-week WD for the first time (LOb). In C57BL/6 J but not DOz mice, WC animals had significantly higher blood insulin levels than LOb controls. All WC animals exhibited significantly greater beta cell activity than LOb controls despite similar fat mass, glucose tolerance, liver lipid levels and insulin-stimulated glucose uptake in adipose tissue. CONCLUSION: Following weight loss, metabolic outcomes return to baseline in C57BL/6 J mice with obesity. However, genetic diversity significantly impacts this response. A period of weight loss does not provide lasting benefits after weight regain, and weight cycling is detrimental and associated with hyperinsulinemia and elevated basal insulin secretion.

5.
Opt Express ; 32(9): 15667-15679, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859212

RESUMO

We report on the theoretical and experimental investigations of optical microcavities consisting in the plane-plane arrangement of a broadband high-reflectivity mirror and a suspended one-dimensional grating mirror possessing a high-quality factor Fano resonance. By varying the length of these cavities from the millimeter to the few-micron range, we observe at short lengths the reduction of the spectral linewidth predicted to occur for such a Fano cavity as compared to a conventional broadband mirror cavity with the same length and internal losses. Such narrow linewidth and small modevolume microcavities with high-mechanical quality ultrathin mirrors will be attractive for a wide range of applications within optomechanics and sensing.

6.
Artigo em Inglês | MEDLINE | ID: mdl-38932581

RESUMO

BACKGROUND: Prone position ventilation (PPV) is recommended for patients with COVID-19 induced severe Adult Respiratory Distress Syndrome (ARDS) and is used for patients supported with V-V ECMO as well. The purpose of this study was to describe the use of PPV in these patients focusing on physiological effects with the hypothesis that PPV could reduce oxygen need and improve dynamic compliance. METHODS: This study was a nationwide retrospective analysis of all COVID-19 patients in Denmark from March 2020 - December 2021 with severe ARDS and need of V-V ECMO support. Data on the number of patients treated with PPV, number of PPV sessions, timing, the time spent in prone position, pulmonary physiological response types with analysis of variables affecting the response are reported. RESULTS: Out of 68 patients 44 were treated with 220 PPV sessions and a positive clinical response was observed in 80% of patients but only in 45% of sessions. On a single session level, increased compliance was observed in 38% and increased oxygenation in only 15% of 220 sessions, with within-patient heterogeneity. Higher dynamic compliance at the beginning of a PPV session was associated with a lower delta change in dynamic compliance during PPV. The response to a PPV session could not be predicted by the response in the prior session. Dynamic compliance did not change during the ECMO course. CONCLUSION: Eighty percent of patients responded positively during a PPV session, but this was not associated with overall pulmonary improvement. On a single patient level, responses were heterogenous and only 45% of sessions resulted in clinical improvement. Response in dynamic compliance was associated with starting values of compliance.

7.
Proc Natl Acad Sci U S A ; 117(38): 23932-23941, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32900951

RESUMO

DICER is a key enzyme in microRNA (miRNA) biogenesis. Here we show that aerobic exercise training up-regulates DICER in adipose tissue of mice and humans. This can be mimicked by infusion of serum from exercised mice into sedentary mice and depends on AMPK-mediated signaling in both muscle and adipocytes. Adipocyte DICER is required for whole-body metabolic adaptations to aerobic exercise training, in part, by allowing controlled substrate utilization in adipose tissue, which, in turn, supports skeletal muscle function. Exercise training increases overall miRNA expression in adipose tissue, and up-regulation of miR-203-3p limits glycolysis in adipose under conditions of metabolic stress. We propose that exercise training-induced DICER-miR-203-3p up-regulation in adipocytes is a key adaptive response that coordinates signals from working muscle to promote whole-body metabolic adaptations.


Assuntos
Tecido Adiposo/metabolismo , RNA Helicases DEAD-box/metabolismo , Exercício Físico/fisiologia , Ribonuclease III/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Adaptação Fisiológica/fisiologia , Adipócitos/metabolismo , Animais , Células Cultivadas , RNA Helicases DEAD-box/deficiência , RNA Helicases DEAD-box/genética , Feminino , Glicólise , Humanos , Masculino , Camundongos , Camundongos Knockout , MicroRNAs/genética , MicroRNAs/metabolismo , Condicionamento Físico Animal , Ribonuclease III/deficiência , Ribonuclease III/genética
8.
Perfusion ; : 2676591231198798, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37787741

RESUMO

INTRODUCTION: Prone position ventilation (PPV) of patients with adult respiratory distress syndrome (ARDS) supported with veno-venous extracorporeal membrane oxygenation (V-V ECMO) may improve oxygenation and alveolar recruitment and is recommended when extensive dorsal consolidations are present, but only few data regarding adverse events (AE) related to PPV in this group of patients have been published. METHODS: Nationwide retrospective analysis of 68 COVID-19 patients admitted from March 2020 - December 2021 with severe ARDS and need of V-V ECMO support. The number of patients treated with PPV, number of PPV-events, timing, the time spent in prone position, number and causes of AE are reported. Causes to stop the PPV regimen and risk factors for AE were explored. RESULTS: 44 out of 68 patients were treated with PPV, and 220 PPV events are evaluated. AE were identified in 99 out of 220 (45%) PPV events and occurred among 31 patients (71%). 1 fatal PPV related AE was registered. Acute supination occurred in 19 events (9%). Causes to stop the PPV regimen were almost equally distributed between effect (weaned from ECMO), no effect, death (of other reasons) and AE. Frequent causes of AE were pressures sores and ulcers, hypoxia, airway related and ECMO circuit related. Most AE occurred during patients first or second PPV event. CONCLUSIONS: PPV treatment was found to carry a high incidence of PPV related AE in these patients. Causes and preventive measures to reduce occurrence of PPV related AE during V-V ECMO support need further exploration.

9.
Opt Express ; 30(3): 3962-3972, 2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35209644

RESUMO

We report on the design and experimental characterization of a suspended silicon nitride subwavelength grating possessing a polarization-independent guided-mode resonance at oblique incidence. At this resonant wavelength we observe that the transverse intensity profile of the transmitted beam is consistent with a first-order spatial differentiation of the incident beam profile in the direction of the grating periodicity, regardless of the incident light polarization. These observations are corroborated by full numerical simulations. The simple one-dimensional and symmetric design, combined with the thinness and excellent mechanical properties of these essentially loss-free dieletric films, is attractive for applications in optical processing, sensing and optomechanics.

10.
Sensors (Basel) ; 22(8)2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35458893

RESUMO

The Radiation and Dust Sensor is one of six sensors of the Mars Environmental Dynamics Analyzer onboard the Perseverance rover from the Mars 2020 NASA mission. Its primary goal is to characterize the airbone dust in the Mars atmosphere, inferring its concentration, shape and optical properties. Thanks to its geometry, the sensor will be capable of studying dust-lifting processes with a high temporal resolution and high spatial coverage. Thanks to its multiwavelength design, it will characterize the solar spectrum from Mars' surface. The present work describes the sensor design from the scientific and technical requirements, the qualification processes to demonstrate its endurance on Mars' surface, the calibration activities to demonstrate its performance, and its validation campaign in a representative Mars analog. As a result of this process, we obtained a very compact sensor, fully digital, with a mass below 1 kg and exceptional power consumption and data budget features.


Assuntos
Poeira , Meio Ambiente Extraterreno , Atmosfera
11.
Wound Repair Regen ; 29(6): 988-995, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34546614

RESUMO

Rapid wound closure is important after arthroplasty procedures to prevent postoperative complications. Platelets are rich in growth factors and leukocytes contribute to innate immunity. We hypothesized that topical leukocyte platelet-rich plasma (L-PRP) derived from the blood of patients would be beneficial to wound healing. In this randomized controlled trial, patients subjected to elective total hip arthroplasty (THA) were assigned by concealed allocation either L-PRP application onto the sutured fascia or no application (control) after the THA intervention. In addition, all patients received 1.5 g protein/kg, 5 g L-arginine, 500 mg vitamin C and 44 mg zinc daily over the 4-week postoperative period to obtain optimal nutrition. The primary endpoint was complete healing of the skin incision. The secondary endpoints were blood transfusions, length of hospital stay, pain and wound infections. Sixteen patients in the L-PRP group and 17 patients in the control group completed the trial. L-PRP treatment accelerated complete wound healing after 3 weeks (seven in the L-PRP group vs. zero in the control group, p = 0.003) and after 4 weeks (12 in the L-PRP group vs. six in the control group, p = 0.037). No postoperative superficial wound infections occurred within 4 weeks, and there were no significant differences in the other secondary outcomes. L-PRP generated in 10 sex-matched healthy volunteers revealed increased concentrations of platelets (5.8-fold) and leukocytes (2.3-fold) compared with those in whole blood. Furthermore, the concentration of keratinocyte mitogen epidermal growth factor in L-PRP (380 ± 130 pg/ml, mean ± SD) was higher (p < 0.001) than that in serum (130 ± 26 pg/ml). In conclusion, a single intraoperative local application of L-PRP promoted wound healing after THA, possibly mediated by EGF receptor agonists.


Assuntos
Artroplastia de Quadril , Plasma Rico em Plaquetas , Humanos , Leucócitos , Infecção da Ferida Cirúrgica/prevenção & controle , Cicatrização
12.
Eur J Orthop Surg Traumatol ; 31(6): 1029-1036, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33244659

RESUMO

PURPOSE: Elevated levels of serum metal ions can be found in some patients with metal-on-metal (MoM) hip replacements. This study seeks to identify whether there is a significant association between the contact patch to rim distance (CPRD) and the anterior center edge angle (ACEA), respectively, and serum cobalt (Co) and chromium (Cr) levels in patients treated with unilateral MoM hip replacements by using standing anteroposterior and false profile view radiographs. METHODS: This is a retrospective analysis on 53 patients with either unilateral ReCap or M2a-Magnum MoM hip replacements operated in 2006 or 2007. Univariate linear regression and multivariable linear regression (MLR) analyses were performed using the CPRD and ACEA along with risk factors for elevated serum levels of Co and Cr previously suggested in the literature as explanatory variables. Serum Co and Cr were measured using inductively coupled plasma mass spectrometry. RESULTS: The MLR model showed that the same three variables (gender, CPRD and ACEA) were significantly associated with serum levels of both Co and Cr explaining approximately half of the variation. A univariate analysis showed a polynomial association between both anteversion angle and the ACEA with serum levels of Co and Cr. The vertex of the polynomial function was located at approximately 20° and 40°, respectively. CONCLUSION: Gender, CPRD and ACEA are independently associated with serum levels of Co and Cr. Both ACEA and anteversion angles have optimae associated with low serum metal levels which may be useful for post-surgery evaluation of cup positioning.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Próteses Articulares Metal-Metal , Cromo , Cobalto , Prótese de Quadril/efeitos adversos , Humanos , Próteses Articulares Metal-Metal/efeitos adversos , Desenho de Prótese , Estudos Retrospectivos
13.
PLoS Med ; 16(10): e1002936, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31574097

RESUMO

BACKGROUND: Physical exercise has been shown to be effective in relation to fatigue, aerobic fitness, and lower body strength in men with prostate cancer. However, research into the clinically relevant effects of interventions conducted in heterogeneous patient populations and in real-life clinical practice settings is warranted. METHODS AND FINDINGS: We conducted a pragmatic, multicentre, parallel randomised controlled trial in 5 Danish urological departments. Recruitment began in May 2015, the first participant was randomised in June 2015, and the last participant was included in February 2017. In total, 214 men with prostate cancer were randomly assigned to either 6 months of free-of-charge football training twice weekly at a local club (football group [FG]) (n = 109) or usual care (usual care group [UG]) (n = 105), including brief information on physical activity recommendations at randomisation. Participants were on average 68.4 (SD 6.2) years old, 157 (73%) were retired, 87 (41%) were on castration-based treatment, 19 (9%) had received chemotherapy, and 41 (19%) had skeletal metastases at baseline. In this 1-year follow-up study, we evaluated the effects of community-based football training on the following outcomes: primary outcome, quality of life; secondary outcomes: continuation of football after 6 months, hip and lumbar spine bone mineral density (BMD), mental health score, fat and lean body mass, and safety outcomes, i.e., fractures, falls, and hospital admissions. Intention to treat (ITT) and per protocol (PP) analyses were conducted. No statistically significant between-group difference was observed in change in prostate-cancer-specific quality of life (ITT: 1.9 points [95% CI -1.9 to 5.8], p = 0.325; PP: 3.6 points [95% CI -0.9 to 8.2], p = 0.119). A statistically significant between-group difference was observed in change in total hip BMD, in favour of FG (0.007 g/cm2 [95% CI 0.004 to 0.013], p = 0.037). No differences were observed in change in lumbar spine BMD or lean body mass. Among patients allocated to football, 59% chose to continue playing football after the end of the 6-month intervention period. At 1-year follow-up in the PP population, FG participants had more improvement on the Mental Component Summary (2.9 [95% CI 0.0 to 5.7], p = 0.048 points higher) than UG participants, as well as a greater loss of fat mass (-0.9 kg [95% CI -1.7 to -0.1], p = 0.029). There were no differences between groups in relation to fractures or falls. Hospital admissions were more frequent in UG compared to FG (33 versus 20; the odds ratio based on PP analysis was 0.34 for FG compared to UG). There were 3 deaths in FG and 4 in UG. Main limitations of the study were the physically active control group and assessment of physical activity by means of self-report. CONCLUSIONS: In this trial, participants allocated to football appeared to have improved hip BMD and fewer hospital admissions. Men who played football more than once a week for 1 year lost fat mass and reported improved mental health. Community-based football proved to be acceptable, even when club membership was not subsidised. TRIAL REGISTRATION: ClinicalTrials.gov NCT02430792.


Assuntos
Exercício Físico , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/reabilitação , Futebol , Acidentes por Quedas/prevenção & controle , Idoso , Densidade Óssea , Dinamarca , Terapia por Exercício , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Admissão do Paciente , Neoplasias da Próstata/psicologia , Qualidade de Vida , Resultado do Tratamento
14.
Appl Environ Microbiol ; 85(10)2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30877113

RESUMO

Some lactic acid bacteria, especially Lactobacillus spp., possess adhesive properties enabling colonization of the human gastrointestinal tract. Two probiotic Lactobacillus plantarum strains, WCSF1 and 299v, display highly different mannose-specific adhesion, with L. plantarum 299v being superior to L. plantarum WCFS1 based on a yeast agglutination assay. A straightforward correlation between the mannose adhesion capacity and domain composition of the mannose-specific adhesin (Msa) in the two strains has not been demonstrated previously. In this study, we analyzed the promoter regions upstream of the msa gene encoding a mannose-specific adhesin in these two strains. The promoter region was mapped by primer extension and DNA sequence analysis, and only a single nucleotide change was identified between the two strains. However, Northern blot analysis showed a stronger msa transcript band in 299v than in WCFS1 correlating with the different adhesion capacities. During the establishment of a high-throughput yeast agglutination assay, we isolated variants of WCFS1 that displayed a very strong mannose-specific adhesion phenotype. The region upstream of the msa gene in these variants showed an inversion of a 104-bp fragment located between two perfectly inverted repeats present in the untranslated leader region. The inversion disrupts a strong hairpin structure that otherwise most likely would terminate the msa transcript. In addition, the ribosome binding site upstream of the msa gene, which is also masked within this hairpin structure, becomes accessible upon inversion, thereby increasing the frequency of translation initiation in the variant strains. Furthermore, Northern blot analysis showed a higher abundance of the msa transcript in the variants than in the wild type, correlating with a strong-Msa phenotype.IMPORTANCE Probiotic strains possess adhesive properties enabling colonization of the human intestinal tract through interactions between molecules present on the probiotic bacteria and components of the epithelial surface. In Lactobacillus plantarum, interaction is mediated through bacterial surface proteins like Msa, which binds to mannose residues present on the intestinal cells. Such interactions are believed to be important for the health-promoting effects of probiotics, including displacement of pathogens, immunomodulation, and protective effects on the intestinal barrier function. In this study, we have identified a new molecular switch controlling expression of the msa gene in L. plantarum strain WCFS1. Strains with increased msa expression could be valuable in the development and manufacture of improved probiotic products.


Assuntos
Adesinas Bacterianas/genética , Regulação Bacteriana da Expressão Gênica , Lactobacillus plantarum/genética , Manose/metabolismo , Probióticos , Adesinas Bacterianas/metabolismo , Aglutinação , Trato Gastrointestinal/microbiologia , Humanos , Lactobacillus plantarum/metabolismo , Saccharomyces cerevisiae/metabolismo
15.
Am J Physiol Endocrinol Metab ; 314(4): E377-E395, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29208611

RESUMO

Nicotinamide adenine dinucleotide (NAD+) can be synthesized by nicotinamide phosphoribosyltransferase (NAMPT). We aimed to determine the role of NAMPT in maintaining NAD+ levels, mitochondrial function, and metabolic homeostasis in skeletal muscle cells. We generated stable Nampt knockdown (sh Nampt KD) C2C12 cells using a shRNA lentiviral approach. Moreover, we applied gene electrotransfer to express Cre recombinase in tibialis anterior muscle of floxed Nampt mice. In sh Nampt KD C2C12 myoblasts, Nampt and NAD+ levels were reduced by 70% and 50%, respectively, and maximal respiratory capacity was reduced by 25%. Moreover, anaerobic glycolytic flux increased by 55%, and 2-deoxyglucose uptake increased by 25% in sh Nampt KD cells. Treatment with the NAD+ precursor nicotinamide riboside restored NAD+ levels in sh Nampt cells and increased maximal respiratory capacity by 18% and 32% in control and sh Nampt KD cells, respectively. Expression of Cre recombinase in muscle of floxed Nampt mice reduced NAMPT and NAD+ levels by 38% and 43%, respectively. Glucose uptake increased by 40%, and mitochondrial complex IV respiration was compromised by 20%. Hypoxia-inducible factor (HIF)-1α-regulated genes and histone H3 lysine 9 (H3K9) acetylation, a known sirtuin 6 (SIRT6) target, were increased in shNampt KD cells. Thus, we propose that the shift toward glycolytic metabolism observed, at least in part, is mediated by the SIRT6/HIF1α axis. Our findings suggest that NAMPT plays a key role for maintaining NAD+ levels in skeletal muscle and that NAMPT deficiency compromises oxidative phosphorylation capacity and alters energy homeostasis in this tissue.


Assuntos
Citocinas/genética , Metabolismo Energético/genética , Mitocôndrias Musculares/fisiologia , Músculo Esquelético/metabolismo , Mioblastos/metabolismo , NAD/metabolismo , Nicotinamida Fosforribosiltransferase/genética , Animais , Metabolismo dos Carboidratos/genética , Células Cultivadas , Citocinas/metabolismo , Homeostase/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Nicotinamida Fosforribosiltransferase/metabolismo , Fosforilação Oxidativa , Transdução de Sinais/genética
16.
Opt Express ; 26(18): A788-A795, 2018 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-30184838

RESUMO

This paper describes a systematic design study of periodic gold-nanostrip arrays placed on a thin film aimed at enhancing the electric field inside the film when irradiated by light. Based on the study, a "selection rule" is proposed, which provides optimization-based design methods with an a priori choice between field-enhancement dominated by coupling to guided modes, by plasmonic near-field enhancement or by a mix hereof. An appropriate choice of wavelength and grating period is shown to selectively suppress or include waveguiding effects for the optimized designs. The validity of the selection rule is demonstrated through a numerical topology optimization study in which gold nanostrips are optimized for electric-field enhancement in an erbium-doped TiO2 thin film, targeting increased spectral upconversion in the erbium ions. The obtained designs exhibit waveguide excitation within the predicted intervals and, for light polarized perpendicularly to the strips, plasmonic response outside.

17.
J Arthroplasty ; 33(5): 1412-1420, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29276121

RESUMO

BACKGROUND: The large-diameter metal-on-metal hip prostheses were expected to have low wear and reduced dislocation rate compared to the traditional metal-on-polyethylene implants. We compare 2 such prostheses, the ReCap resurfacing implant and the M2a-Magnum stemmed implant, with the C2a ceramic-on-ceramic stemmed implant as to clinical performance, serum concentrations of prosthesis metals, and the durability of the implants in a randomized, controlled clinical trial at 7 years of follow-up. METHODS: All included patients had osteoarthritis. Preoperatively, the size of the implants was estimated from a magnetic resonance imaging (MRI) scan. Follow-up data included serum cobalt and chromium concentrations, Oxford and Harris Hip Scores, leg press and abduction force, 6-minute walk distance, WOMAC and SF-36 self-assessment scores, and from the 7th postoperative year also ultrasonography (US) examination of the soft tissue adjacent to the implant as well as MRI with metal artifact reduction sequence (MARS-MRI) when indicated. RESULTS: One hundred fifty-two hips in 146 patients were included. The serum cobalt and chromium concentrations were significantly higher for the 2 metal-on-metal prostheses than for the ceramic-on-ceramic, with the M2a-Magnum as the highest. No significant difference was found between the groups concerning physical performance measurements and scores as well as dislocations and prosthesis survival. Five revisions were done and concerned all groups, for reasons of pain, high serum cobalt and chromium concentrations, cystic fluid collection around the joint, and infection. Metal concentrations, US, and MARS-MRI contributed to the decision making regarding prosthesis revision. CONCLUSION: Metal concentrations were significantly higher for the metal-on-metal prostheses than for the ceramic-on-ceramic. The clinical performance was good in all 3 prosthesis groups. Metal concentrations, US, and MARS-MRI findings were of use to identify hips needing revision. ID Number in ClinicalTrials.gov PRS: NCT00284674.


Assuntos
Artroplastia de Quadril/instrumentação , Artroplastia de Quadril/métodos , Prótese de Quadril , Desenho de Prótese , Falha de Prótese , Adulto , Idoso , Cerâmica , Cromo/sangue , Cobalto/sangue , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Imageamento por Ressonância Magnética , Masculino , Metais , Pessoa de Meia-Idade , Polietileno , Resultado do Tratamento
18.
Opt Express ; 25(16): 19354-19359, 2017 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-29041129

RESUMO

A two-particle model is proposed which enables the assessment of particle-particle interactions in large, sparse arrays of randomly distributed plasmonic metal nanoparticles of arbitrary geometry in inhomogeneous environments. The two-particle model predicts experimentally observed peak splittings in the extinction cross section spectrum for randomly distributed gold nanocones on a TiO2:Er3+ thin film with average center-to-center spacings of 3-5 diameters. The main physical mechanism responsible is found to be interference between the incident field and the far-field component of the single-particle scattered field which is guided along the film.

19.
Pharm Res ; 34(9): 1970-1983, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28646324

RESUMO

PURPOSE: Production and characterization of a chimeric fusion protein (GMZ2'.10C) which combines epitopes of key malaria parasite antigens: glutamate-rich protein (GLURP), merozoite surface protein 3 (MSP3), and the highly disulphide bonded Pfs48/45 (10C). GMZ2'.10C is a potential candidate for a multi-stage malaria vaccine that targets both transmission and asexual life-cycle stages of the parasite. METHODS: GMZ2'.10C was produced in Lactococcus lactis and purified using either an immunoaffinity purification (IP) or a conventional purification (CP) method. Protein purity and stability was analysed by RP-HPLC, SEC-HPLC, 2-site ELISA, gel-electrophoresis and Western blotting. Structural characterization (mass analysis, peptide mapping and cysteine connectivity mapping) was performed by LC-MS/MS. RESULTS: CP-GMZ2'.10C resulted in similar purity, yield, structure and stability as compared to IP-GMZ2'.10C. CP-GMZ2'.10C and IP-GMZ2'.10C both elicited a high titer of transmission blocking (TB) antibodies in rodents. The intricate disulphide-bond connectivity of C-terminus Pfs48/45 was analysed by tandem mass spectrometry and was established for GMZ2'.10C and two reference fusion proteins encompassing similar parts of Pfs48/45. CONCLUSION: GMZ2'.10C, combining GMZ2' and correctly-folded Pfs48/45 can be produced by the Lactoccus lactis P170 based expression system in purity and quality for pharmaceutical development and elicit high level of TB antibodies. The cysteine connectivity for the 10C region of Pfs48/45 was revealed experimentally, providing an important guideline for employing the Pfs48/45 antigen in vaccine design.


Assuntos
Antígenos de Protozoários/uso terapêutico , Vacinas Antimaláricas/uso terapêutico , Malária Falciparum/prevenção & controle , Plasmodium falciparum/imunologia , Proteínas de Protozoários/uso terapêutico , Sequência de Aminoácidos , Animais , Formação de Anticorpos , Antígenos de Protozoários/química , Antígenos de Protozoários/genética , Antígenos de Protozoários/imunologia , Clonagem Molecular , Humanos , Lactococcus lactis/genética , Vacinas Antimaláricas/química , Vacinas Antimaláricas/genética , Vacinas Antimaláricas/imunologia , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Plasmodium falciparum/química , Plasmodium falciparum/genética , Plasmodium falciparum/crescimento & desenvolvimento , Estabilidade Proteica , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia , Ratos Wistar , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/uso terapêutico
20.
J Arthroplasty ; 30(6): 993-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25720854

RESUMO

We perform a non-randomized, consecutive pilot study on the ASR and ReCap resurfacing hip implants and have completed 7 years follow-up. Forty-six non-osteoporotic patients with hip osteoarthritis and anatomical conditions suitable for resurfacing were divided into 2 equal groups and operated sequentially, starting with the ASR implants. Sixteen patients operated with ASR and 19 patients with ReCap have been followed-up. There were no significant differences between the two groups preoperatively as to physical function, pain, or femoral BMD. The serum concentrations of cobalt and chromium were higher in the ASR group from 1/2 to 7 years postoperatively. Five of 16 ASR implants have been revised, and none of the ReCap implants. BMD below the femoral component increased in both groups.


Assuntos
Artroplastia de Quadril/instrumentação , Prótese de Quadril/estatística & dados numéricos , Osteoartrite do Quadril/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril/estatística & dados numéricos , Densidade Óssea , Cromo/sangue , Cobalto/sangue , Feminino , Fêmur/fisiologia , Fêmur/cirurgia , Seguimentos , Prótese de Quadril/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Desenho de Prótese , Falha de Prótese , Reoperação
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