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1.
Fitoterapia ; : 106055, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38838822

RESUMO

This study evaluates the antibacterial effectiveness of Origanum vulgare hydroethanolic extract, both independently and in combination with antibiotics, against Escherichia coli strains associated with avian colibacillosis-a significant concern for the poultry industry due to the rise of antibiotic-resistant E. coli. The urgent demand for new treatments is addressed by analyzing the extract's phytochemical makeup via High-Performance Liquid Chromatography (HPLC), which identified sixteen phenolic compounds. Antibacterial activity was determined through agar diffusion and the measurement of minimum inhibitory and bactericidal concentrations (MIC and MBC), showing moderate efficacy (MIC: 3.9 to 7.8 mg/ml, MBC: 31.2 to 62.4 mg/ml). Combining the extract with antibiotics like ampicillin and tetracycline amplified antibacterial activity, indicating a synergistic effect and highlighting the importance of combinatory treatments against resistant strains. Further analysis revealed the extract's mechanisms of action include disrupting bacterial cell membrane integrity and inhibiting ATPase/H+ proton pumps, essential for bacterial survival. Moreover, the extract effectively inhibited and eradicated biofilms, crucial for preventing bacterial colonization. Regarding cytotoxicity, the extract showed no hemolytic effect at 1 to 9 mg/ml concentrations. These results suggest Origanum vulgare extract, particularly when used with antibiotics, offers a promising strategy for managing avian colibacillosis, providing both direct antibacterial benefits and moderating antibiotic resistance, thus potentially reducing the economic impact of the disease on the poultry industry.

2.
RSC Adv ; 14(18): 12533-12555, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38689800

RESUMO

This study investigates the corrosion inhibition potential of 3,4-dimethoxy phenyl thiosemicarbazone (DMPTS) for copper in 1 M hydrochloric acid (HCl) solutions, aiming to disclose the mechanism behind its protective action. Through an integrative methodology encompassing electrochemical analyses-such as weight loss measurements, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS)-we quantitatively evaluate the corrosion protection efficacy of DMPTS. It was determined that the optimal concentration of DMPTS markedly boosts the corrosion resistance of copper, achieving an impressive inhibition efficiency of up to 89% at 400 ppm. The formation of a protective layer on the copper surface, a critical aspect of DMPTS's inhibitory action, was characterized using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). These techniques provided empirical evidence of surface morphology modifications and roughness changes, affirming the formation of a protective barrier against corrosion. A significant advancement in our study was the application of Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy, which identified chemical adsorption as the definitive mechanism of corrosion inhibition by DMPTS. The ATR-FTIR results explicitly demonstrated the specific interactions between DMPTS molecules and the copper surface, indicative of a robust protective adsorbed layer formation. This mechanistic insight, crucial to understanding the inhibitory process, aligns with the protective efficacy observed in electrochemical and surface analyses. Theoretical support, provided by the Quantum Theory of Atoms in Molecules (QTAIM) and quantum chemical computations, further validated the strong molecular interaction between DMPTS and copper, corroborating the experimental findings. Collectively, this research not only confirms the superior corrosion inhibition performance of DMPTS in an acidic setting but also elucidates the chemical adsorption mechanism as the foundation of its action, offering valuable insights for the development of effective corrosion inhibitors in industrial applications.

3.
Int J Biol Macromol ; 268(Pt 2): 131832, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38663704

RESUMO

In this comprehensive investigation, a novel pH-responsive hydrogel system comprising mimosa seed mucilage (MSM), ß-cyclodextrin (ß-CD), and methacrylic acid (MAA) was developed via free radical polymerization technique to promote controlled drug delivery. The hydrogel synthesis involved strategic variations in polymer, monomer, and crosslinker content in fine-tuning its drug-release properties. The resultant hydrogel exhibited remarkable pH sensitivity, selectively liberating the model drug (Capecitabine = CAP) under basic conditions while significantly reducing release in an acidic environment. Morphological, thermal, and structural analyses proved that CAP has a porous texture, high stability, and an amorphous nature. In vitro drug release experiments showcased a sustained and controlled release profile. Optimum release (85.33 %) results were recorded over 24 h at pH 7.4 in the case of MMB9. Pharmacokinetic evaluation in healthy male rabbits confirmed bioavailability enhancement and sustained release capabilities. Furthermore, rigorous toxicity evaluations and histopathological analyses ensured the safety and biocompatibility of the hydrogel. This pH-triggered drug delivery system can be a promising carrier system for drugs involving frequent administrations.


Assuntos
Preparações de Ação Retardada , Liberação Controlada de Fármacos , Hidrogéis , Mimosa , Sementes , beta-Ciclodextrinas , Concentração de Íons de Hidrogênio , Animais , Coelhos , Hidrogéis/química , Mimosa/química , Sementes/química , beta-Ciclodextrinas/química , Masculino , Sistemas de Liberação de Medicamentos , Mucilagem Vegetal/química , Portadores de Fármacos/química , Ácidos Polimetacrílicos/química
4.
Cell Mol Biol (Noisy-le-grand) ; 70(1): 67-79, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38372111

RESUMO

Bacillus sp. RTS11, a xylanolytic strain, was isolated from the Algerian desert rocks. Genetic analysis revealed a remarkable 98.69% similarity to Bacillus pumilus. We harnessed optimization techniques, including Plackett-Burman screening and Box-Behnken optimization design, to amplify xylanase production and activity. The outcome of these efforts was an optimized medium that yielded an impressive xylanase production titer of 448.89 U, a threefold increase compared to the non-optimized medium (146 U). The Purification of xylanase was achieved through the three-phase partitioning technique, employing t-butanol and various chromatographic methods. Notably, anion exchange chromatography led to isolating a highly pure enzyme with a molecular weight of 60 kDa. The xylanase exhibited its peak activity at a temperature of 60°C and a pH of 9.0. When applied to pulp pretreatment, 20 U/g of xylanase demonstrated a substantial increase in the release of phenolic and chromophore compounds while reducing sugar content in the pulp. Furthermore, this versatile xylanase shows its ability to efficiently hydrolyze a variety of agro-industrial residues, including wheat bran, corn and grape waste, wheat straw, and sugarcane bagasse. These findings underscore the significant potential of this xylanase enzyme in biobleaching processes and the utilization of agro-industrial waste, opening up exciting avenues for sustainable and environmentally friendly industrial applications.


Assuntos
Bacillus , Saccharum , Bacillus/genética , Celulose , Endo-1,4-beta-Xilanases , Fibras na Dieta , Concentração de Íons de Hidrogênio
5.
ACS Omega ; 8(49): 47224-47238, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38107914

RESUMO

Natural and fragrant compounds, essential oils (EOs) extracted from plants through hydrodistillation, are gaining popularity as eco-friendly and sustainable agents to protect metals and alloys from corrosion in acidic environments. This research focused on extracting and characterizing an EO obtained from the Cuminum cyminum (CC) plant native to India. The study aimed to evaluate the inhibitory properties of this EO on mild steel in a 0.5 M HCl solution at different concentrations. Various analytical techniques, including potentiodynamic polarization curves, electrochemical impedance spectroscopy, optical microscopy, infrared spectroscopy, and proton magnetic resonance, were employed to assess the effectiveness of this EO extract. Our findings indicate that the Cuminum cyminum L (CCL) extract effectively reduces the corrosion of mild steel in hydrochloric acid with an inhibition efficiency ranging from 79.69 to 98.76%. The optimal inhibition concentration was 2 g/L of EO, and surface analysis confirmed the formation of a protective layer. Furthermore, our results suggest that the inhibitor binds to the metal surface through a charge-transfer process, creating a protective film. Finally, we utilized theoretical calculations and molecular dynamics simulations to elucidate the inhibition mechanism on both a global and local scale.

6.
Molecules ; 28(20)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37894631

RESUMO

Eucalyptus, a therapeutic plant mentioned in the ancient Algerian pharmacopeia, specifically two species belonging to the Myrtaceae family, E. radiata and E. cinerea, were investigated in this study for their antibacterial, antioxidant, and anti-inflammatory properties. The study used aqueous extracts (AE) obtained from these plants, and the extraction yields were found to be different. The in vitro antibacterial activity was evaluated using a disc diffusion assay against three typical bacterial strains. The results showed that the two extracts were effective against all three strains. Both extracts displayed significant antioxidant activity compared to BHT. The anti-inflammatory impact was evaluated using a protein (BSA) inhibition denaturation test. The E. radiata extract was found to inhibit inflammation by 85% at a concentration of 250 µg/mL, significantly higher than the Aspirin. All phytoconstituents present good pharmacokinetic characteristics without toxicity except very slight toxicity of terpineol and cineol and a maximum binding energy of -7.53 kcal/mol for its anti-TyrRS activity in silico. The study suggests that the extracts and their primary phytochemicals could enhance the efficacy of antibiotics, antioxidants, and non-steroidal anti-inflammatory drugs (NSAIDs). As pharmaceutical engineering experts, we believe this research contributes to developing natural-based drugs with potential therapeutic benefits.


Assuntos
Antioxidantes , Extratos Vegetais , Antioxidantes/farmacologia , Antioxidantes/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antibacterianos/farmacologia , Antibacterianos/química , Anti-Inflamatórios/farmacologia , Compostos Fitoquímicos/química
7.
Int J Biol Macromol ; 253(Pt 4): 127032, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37742901

RESUMO

In current work, quince seed mucilage and ß-Cyclodextrin based pH regulated hydrogels were developed using aqueous free radical polymerization to sustain Capecitabine release patterns and to overcome its drawbacks, such as high dose frequency, short half-life, and low bioavailability. Developed networks were subjected to thermal analysis, Fourier transforms infrared spectroscopy, powder x-ray diffraction, elemental analysis, scanning electron microscopy, equilibrium swelling, and in-vitro release investigations to assess the network system's stability, complexation, morphology, and pH responsiveness. Thermally stable pH-responsive cross-linked networks were formed. Nanocomposite hydrogels were prepared by incorporating Capecitabine-containing clay into the swollen hydrogels. All the formulations exhibited equilibrium swelling ranging from 67.98 % to 92.98 % at pH 7.4. Optimum Capecitabine loading (88.17 %) was noted in the case of hydrogels, while it was 74.27 % in nanocomposite hydrogels. Excellent gel content (65.88 %-93.56 %) was noticed among developed formulations. Elemental analysis ensured the successful incorporation of Capecitabine. Nanocomposite hydrogels released 80.02 % longer than hydrogels after 30 h. NC hydrogels had higher t1/2 (10.57 h), AUC (121.52 µg.h/ml), and MRT (18.95 h) than hydrogels in oral pharmacokinetics. These findings imply that the pH-responsive carrier system may improve Capecitabine efficacy and reduce dosing frequency in cancer therapy. Toxicity profiling proved the system's safety, non-toxicity, and biocompatibility.


Assuntos
Rosaceae , beta-Ciclodextrinas , Metacrilatos/química , Capecitabina , Nanogéis , Polímeros , Sementes , Polissacarídeos , Hidrogéis/química , beta-Ciclodextrinas/química , Concentração de Íons de Hidrogênio
8.
Diabetes Obes Metab ; 25(12): 3444-3452, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37694802

RESUMO

Obesity is a debilitating disease of global proportions that necessitates refined, concept-driven therapeutic approaches. Policy makers, the public and even health care professionals, but also individuals with obesity harbour many misconceptions regarding this disease, which leads to prejudice, negative attitudes, stigmatization, discrimination, self-blame, and failure to provide and finance adequate medical care. Decades of intensive, successful scientific research on obesity have only had a very limited effect on this predicament. We propose a science-based, easy-to-understand conceptual model that synthesizes the complex pathogenesis of obesity including biological, psychological, social, economic and environmental aspects with the aim to explain and communicate better the nature of obesity and currently available therapeutic modalities. According to our integrative 'Behavioral Balance Model', 'top-down cognitive control' strategies are implemented (often with limited success) to counterbalance the increased 'bottom-up drive' to gain weight, which is triggered by biological, psycho-social and environmental mechanisms in people with obesity. Besides offering a deeper understanding of obesity, the model also highlights why there is a strong need for multimodal therapeutic approaches that may not only increase top-down control but also reduce a pathologically increased bottom-up drive.


Assuntos
Obesidade , Humanos , Obesidade/etiologia , Obesidade/terapia , Obesidade/psicologia , Causalidade
9.
Saudi Pharm J ; 31(8): 101671, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37484541

RESUMO

Background & Objectives: This study aimed to create a controlled delivery system for Tapentadol Hydrochloride by developing interpenetrating networks (IPNs) of Natrosol-Pectin copolymerized with Acrylic Acid and Methylene bisacrylamide, and to analyze the effects of various ingredients on the physical and chemical characteristics of the IPNs. Methods: Novel Tapentadol Hydrochloride-loaded Natrosol-Pectin based IPNs were formulated by using the free radical polymerization technique. Co-polymerization of Acrylic Acid (AA) with Natrosol and Pectin was performed by using Methylene bisacrylamide (MBA). Ammonium persulfate (APS) was used as the initiator of crosslinking process. The impact of ingredients i.e. Natrosol, Pectin, MBA, and Acrylic Acid on the gel fraction, porosity, swelling (%), drug loading, and drug release was investigated. FTIR, DSC, TGA, SEM and EDX studies were conducted to confirm the grafting of polymers and to evaluate the thermal stability and surface morphology of the developed IPNs. Results: Swelling studies exhibited an increase in swelling percentage from 84.27 to 91.17% upon increasing polymer (Natrosol and Pectin) contents. An increase in MBA contents resulted in a decrease in swelling from 85 to 67.63%. Moreover, the swelling was also observed to increase with higher AA contents. Significant drug release was noted at higher pH instead of gastric pH value. Oral toxicological studies revealed the nontoxic and biocompatible nature of Natrosol-Pectin IPNs. Interpretation & Conclusion: The developed IPNs were found to be an excellent system for the controlled delivery of Tapentadol Hydrochloride.

10.
Obes Res Clin Pract ; 17(4): 361-365, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37380506

RESUMO

INTRODUCTION: Craniopharyngioma is a brain tumor, resection which often results in hypothalamic damage leading to severe obesity. While small case series and case-control studies have shown the benefits of bariatric surgery in patients with craniopharyngioma-related hypothalamic obesity, long-term results (>5 years) have not been reported so far. METHODS: We analyzed data from 3 cases with craniopharyngioma-related hypothalamic obesity who had undergone (one proximal, two very long limb distal) Roux-en Y gastric bypass (RYGB) surgery 7, 8, and 14 years before their latest follow-up visit. RESULTS: Percentage of total weight loss varied across the 3 patients (11%, 26%, 32%). Preexisting type 2 diabetes markedly improved in 2 patients with one showing a temporary and one a persisting remission. At RYGB surgery one patient was diagnosed to have liver cirrhosis (intraoperative biopsy), but liver function remained stable or even improved during a 7-year follow-up period. One patient required proximalisation of lower anastomosis (distal RYGB) because of severe hypoproteinemia and diarrhea which resolved after revision. Another patient temporarily developed alcohol abuse that led to weight regain, but his weight decreased when alcohol consumption became under control. Importantly, all three patients stated in a standardized questionnaire that they have benefited and that they would recommend RYGB surgery to another person. CONCLUSION: Despite showing an unsatisfying weight loss result in one patient and distinct complications in the other two patients, all patients clearly showed long-term persisting benefits. Moreover, self-reported outcomes confirm that it was the right decision to recommend RYGB to our patients displaying craniopharyngioma-related hypothalamic obesity.


Assuntos
Craniofaringioma , Diabetes Mellitus Tipo 2 , Derivação Gástrica , Obesidade Mórbida , Neoplasias Hipofisárias , Humanos , Derivação Gástrica/métodos , Craniofaringioma/complicações , Craniofaringioma/cirurgia , Seguimentos , Diabetes Mellitus Tipo 2/complicações , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Obesidade/complicações , Obesidade/cirurgia , Redução de Peso , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
12.
J Environ Manage ; 305: 114393, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34979359

RESUMO

This work employed a unique kind of vinicultural biomass (grape residues) to generate fermentative hydrogen. This form of biomass serves two purposes (contains substrate and inoculum). Four mathematical model methods were established; these models were used to represent the fluctuation of hydrogen generation and other fermentation products (organic acids, alcohols), the consumption of substrates included in biomass, and bacterial growth. One of these models was verified using experimental data and used to represent all of the metabolic pathways of bacteria contained in the medium and the interaction between products and substrates. The optimal biomass load, 60 g COD (Chemical Oxygen Demand)/L with a concentration of 0.22 mol of hexose and 0.0444 mol of tartrate offers the best hydrogen yield.


Assuntos
Reatores Biológicos , Hidrogênio , Análise da Demanda Biológica de Oxigênio , Biomassa , Fermentação , Hidrogênio/análise
15.
Allergy ; 76(7): 2166-2176, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33605465

RESUMO

BACKGROUND: There is controversy whether taking ß-blockers or ACE inhibitors (ACEI) is a risk factor for more severe systemic insect sting reactions (SSR) and whether it increases the number or severity of adverse events (AE) during venom immunotherapy (VIT). METHODS: In this open, prospective, observational, multicenter trial, we recruited patients with a history of a SSR and indication for VIT. The primary objective of this study was to evaluate whether patients taking ß-blockers or ACEI show more systemic AE during VIT compared to patients without such treatment. RESULTS: In total, 1,425 patients were enrolled and VIT was performed in 1,342 patients. Of all patients included, 388 (27.2%) took antihypertensive (AHT) drugs (10.4% took ß-blockers, 11.9% ACEI, 5.0% ß-blockers and ACEI). Only 5.6% of patients under AHT treatment experienced systemic AE during VIT as compared with 7.4% of patients without these drugs (OR: 0.74, 95% CI: 0.43-1.22, p = 0.25). The severity of the initial sting reaction was not affected by the intake of ß-blockers or ACEI (OR: 1.14, 95% CI: 0.89-1.46, p = 0.29). In total, 210 (17.7%) patients were re-stung during VIT and 191 (91.0%) tolerated the sting without systemic symptoms. Of the 19 patients with VIT treatment failure, 4 took ß-blockers, none an ACEI. CONCLUSIONS: This trial provides robust evidence that taking ß-blockers or ACEI does neither increase the frequency of systemic AE during VIT nor aggravate SSR. Moreover, results suggest that these drugs do not impair effectiveness of VIT. (Funded by Medical University of Graz, Austria; Clinicaltrials.gov number, NCT04269629).


Assuntos
Anafilaxia , Venenos de Abelha , Mordeduras e Picadas de Insetos , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Dessensibilização Imunológica , Humanos , Estudos Prospectivos , Fatores de Risco
16.
Bioresour Technol ; 320(Pt A): 124334, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33166887

RESUMO

The aim of this work was to assess the performances of wine byproduct biomass for hydrogen production by dark fermentation. Grape must deposits from two grape varieties (Pinot Gris and Chardonnay) were considered, either with external microbial inoculum or without. We show that grape must residues contain endogenous microflora, well adapted to their environment, which can degrade sugars (initially contained in the biomass) to hydrogen without any nutrient addition. Indeed, hydrogen production during endogenous fermentation is as efficient as with an external heat-treated inoculum (2.5 ± 0.4 LH2.L-1reactor and 1.61 ± 0.41 molH2.mol-1consumed hexose, respectively) with a lower energy cost. Hydrogen-producing bacteria were selected from the endogenous microflora during semi-batch bioreactor operation, as shown by T-RFLP profiles and 16S rRNA sequencing, with Clostridium spp. (butyricum, beijerinckii, diolis, roseum) identified as the major phylotype. Such hydrogen production efficiency opens new perspectives for innovating in the valorization of winery by-products.


Assuntos
Vitis , Reatores Biológicos , Fermentação , Hidrogênio , RNA Ribossômico 16S/genética
17.
Bioresour Technol ; 319: 124203, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33045545

RESUMO

The aim of this work was to develop a continuous liquid/gas membrane bioreactor (L/G MBR), i.e. a fermenting module including hollow fibers membrane for L/G separation, for biohydrogen production by dark fermentation. Originally seeded with sludge from a wastewater treatment plant, the L/G MBR underwent a complete stop for eight months. It was then operated without further reseeding. In the present experiment, performed 551 days after the last reseeding, average hydrogen yield of 1.1 ± 0.2 mol per mol glucose added and hydrogen productivity of 135 ± 22 mL/L/h were reached, with acetate and butyrate as the main metabolite products. DNA sequence analysis revealed that Clostridium beijerinckii, Clostridium pasteurianum and Enterobacter sp. were dominant in liquid outlet, in a biofilm on the surface of the hollow fibers and in microbial granules. The L/G MBR has potential for the concentration and the long-term maintenance of an active hydrogen-producing bacterial community without need for reseeding.


Assuntos
Reatores Biológicos , Hidrogênio , Bactérias , Biofilmes , Clostridium , Fermentação
18.
Exp Clin Endocrinol Diabetes ; 128(1): 15-19, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30119136

RESUMO

BACKGROUND: Even subjects with severe obesity show a wide range of metabolic health states, with some showing marked alterations in glucose and lipid metabolism whereas others do not. In severely obese women, we could recently show that the degree of cardiorespiratory fitness is, independently of body mass and age, associated with several markers of glucose and lipid metabolism. AIMS: In our retrospective study on a clinical data set, we questioned whether such an association also exists in severely obese men. METHODS: Cardiorespiratory fitness, i. e. workload (Wpeak) and oxygen uptake (V̇O2,peak) at peak exercise, was assessed by a bicycle spiroergometry in 133 severely obese men (all BMI>35 kg m-2). The following metabolic blood markers were also measured: Fasting serum glucose, insulin, triglycerides (TG), total, low-, high-density cholesterol (Chol, LDL, HDL), uric acid, and whole blood glycated hemoglobin (HbA1c). The Chol/HDL ratio and Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) were also calculated. RESULTS: Multiple stepwise linear regression models including age, body mass, and smoking status as independent variables revealed that Wpeak and V̇O2,peak, explained 4.5 to 10.7% of variance in HbA1c and TG (all beta<- 0.22; all p<0.02). Including fat free mass instead of body mass in respective models revealed that both Wpeak and V̇O2,peak were predictors of HbA1c and TG (all beta<- 0.265; all p<0.013), respectively, while Wpeak also accounted for variance in glucose and Chol (both beta<- 0.259; both p<0.023). CONCLUSIONS: Similar to previous observations in women, our data indicate that cardiorespiratory fitness assessed by bicycle ergospirometry test is associated with glucose and lipid metabolism in severely obese men. The strength of the found associations suggest a mild to moderate influence of cardiorespiratory fitness on metabolic health in severe obesity.


Assuntos
Aptidão Cardiorrespiratória , Hemoglobinas Glicadas/metabolismo , Obesidade , Triglicerídeos/sangue , Adolescente , Adulto , Idoso , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/fisiopatologia , Estudos Retrospectivos , Índice de Gravidade de Doença
19.
Nutr Metab Cardiovasc Dis ; 29(12): 1382-1389, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31558415

RESUMO

BACKGROUND AND AIMS: Severe obesity is associated with poor physical performance but objective data are scarce. METHODS AND RESULTS: Bicycle spiroergometry data with focus on peak oxygen uptake (V˙O2,peak) and workload (Wpeak) from 476 subjects with severe obesity (BMI ≥ 35.0 kg/m2; 70% women) were analysed. In a first step, V˙O2,peak values were compared with reference values calculated upon different formulas (Wassermann; Riddle). Thereafter, multivariate regression analyses were performed to identify determinants of cardiorespiratory fitness. Cardiorespiratory fitness reference classes for V˙O2,peak and Wpeak were established by stratifying the sample upon identified determinants. Absolute V˙O2,peak (1.87 ± 0.47 vs. 2.40 ± 0.59 l/min) and Wpeak (131 ± 26 vs. 168 ± 44 W) were lower in women than men (both p<0.001). Same pattern was found for relative V˙O2,peak and Wpeak, respectively (both p < 0.05). In women, measured V˙O2,peak was lower than predicted by Wasserman (p < 0.001) but not by Riddle (p = 0.961). In men, V˙O2,peak was lower than calculated by both Wasserman and Riddle formulas (both p ≤ 0.003). Multivariate analyses revealed height and age to be the main determinants of cardiorespiratory fitness in both sexes. Subsequent statistical analyses of calculated reference fitness classes revealed that V˙O2,peak and Wpeak differed between the age- and height-defined groups in both sexes (all p < 0.001). CONCLUSION: Data indicate that the evaluation of cardiorespiratory fitness in subjects with severe obesity is largely biased by selected references values for comparison. Our newly established reference fitness classes upon height and age might be helpful in the clinical context when dealing with obese patients.


Assuntos
Aptidão Cardiorrespiratória , Teste de Esforço/normas , Obesidade/diagnóstico , Espirometria/normas , Adolescente , Adulto , Fatores Etários , Ciclismo , Estatura , Índice de Massa Corporal , Tolerância ao Exercício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Consumo de Oxigênio , Valor Preditivo dos Testes , Valores de Referência , Estudos Retrospectivos , Índice de Gravidade de Doença , Fatores Sexuais , Adulto Jovem
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