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1.
J Hazard Mater ; 471: 134337, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38640674

RESUMO

BACKGROUND: Hexafluoropropylene oxide trimer acid (HFPO-TA), a perfluorooctanoic acid (PFOA) substitute, exhibited strong affinity and capability to activate peroxisome proliferator activated receptor gamma (PPARγ), a lipid metabolism regulator, suggesting potential to induce metabolic toxicities. METHODS: Fertile chicken eggs were exposed to 0, 0.5, 1 or 2 mg/kg (egg weight) HFPO-TA and incubated until hatch. Serum from 0- and 3- month-old chickens were subjected to liquid chromatography ultra-high resolution mass spectrometry for HFPO-TA concentration, while liver, pancreas and adipose tissue samples were collected for histopathological assessments. In ovo PPARγ reporter and silencing system were established with lentivirus microinjection. qRT-PCR and immunohistochemistry were utilized to evaluate the expression levels of PPARγ downstream genes. RESULTS: In 3-month-old animals developmentally exposed to HFPO-TA, adipose tissue hyperplasia, hepatic steatosis, pancreas islet hypertrophy and elevated serum free fatty acid / insulin levels were observed. Results of reporter assay and qRT-PCR indicated HFPO-TA-mediated PPARγ transactivation in chicken embryo. Silencing of PPARγ alleviated HFPO-TA-induced changes, while PPARγ agonist rosiglitazone mimicked HFPO-TA-induced effects. qRT-PCR and immunohistochemistry revealed that FASN and GPD1 were upregulated following developmental exposure to HFPO-TA in 3-month-old animals. CONCLUSIONS: Developmental exposure to HFPO-TA induced persistent metabolic toxicities in chickens, in which PPARγ played a central role.

2.
Diabetes Obes Metab ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38465784

RESUMO

AIM: To investigate the differences in utility between conventional dressings and hydrogel dressings for the treatment of diabetic foot ulcer (DFU). METHODS: The PubMed, Embase, Cochrane Library, CNKI, VIP and Wanfang databases were systematically searched up to 21 January 2023. Fixed/random-effect models were used to calculate the odds ratios (ORs) and mean differences (MDs) with 95% confidence intervals (CIs) for the effect size analysis, with heterogeneity determined by I2 statistics. Subgroup analyses of different classes of hydrogel were also conducted. RESULTS: A total of 15 randomized controlled trials with 872 patients were eligible for the present analysis. Compared with conventional dressings, hydrogel dressings significantly improved the healing rate (OR 4.09, 95% CI 2.83 to 5.91), shortened the healing time (MD -11.38, 95% CI -13.11 to -9.66), enhanced granulation formation (MD -3.60, 95% CI -4.21 to -3.00) and epithelial formation (MD -2.82, 95% CI -3.19 to -2.46), and reduced the incidence of bacterial infection (OR 0.10, 95% CI 0.05 to 0.18). CONCLUSION: The meta-analysis showed that hydrogel dressings are more effective in treating DFU compared with conventional dressings.

3.
Ecotoxicol Environ Saf ; 271: 115909, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199220

RESUMO

OBJECTIVE: The effects of air pollution on metabolism have become a popular research topic, and a large number of studies had confirmed that air pollution exposure could induce insulin resistance (IR) to varying degrees, but the results were inconsistent, especially for the long-term exposures. The aim of the current study was to further investigate the potential effects of air pollution on IR. METHODS: A systematic review and meta-analysis of four electronic databases, including PubMed, Embase, Web of Science and Cochrane were conducted, searching for relevant studies published before June 10, 2023, in order to explore the potential relationships between long-term exposure to air pollution and IR. A total of 10 studies were included for data analysis, including seven cohort studies and three cross-sectional studies. Four major components of air pollution, including PM2.5 (particulate matter with an aerodynamic diameter of 2.5 µm or less), PM10 (particulate matter with an aerodynamic diameter of 10 µm or less), NO2, and SO2 were selected, and each analyzed for the potential impacts on insulin resistance, in the form of adjusted percentage changes in the homeostasis assessment model of insulin resistance (HOMA-IR). RESULTS: This systematic review and meta-analysis showed that for every 1 µg/m³ increase in the concentration of selected air pollutants, PM2.5 induced a 0.40% change in HOMA-IR (95%CI: -0.03, 0.84; I2 =67.4%, p = 0.009), while PM10 induced a 1.61% change (95%CI: 0.243, 2.968; I2 =49.1%, p = 0.001). Meanwhile, the change in HOMA-IR due to increased NO2 or SO2 exposure concentration was only 0.09% (95%CI: -0.01, 0.19; I2 =83.2%, p = 0.002) or 0.01% (95%CI: -0.04, 0.06; I2 =0.0%, p = 0.638), respectively. CONCLUSIONS: Long-term exposures to PM2.5, PM10, NO2 or SO2 are indeed associated with the odds of IR. Among the analyzed pollutants, inhalable particulate matters appear to exert greater impacts on IR.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Resistência à Insulina , Humanos , Dióxido de Nitrogênio/análise , Estudos Transversais , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Material Particulado/toxicidade , Material Particulado/análise
4.
Soft Matter ; 20(3): 661-671, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38164039

RESUMO

Motility near solid surfaces plays a key role in the life cycle of bacteria and is essential for biofilm formation, biofilm dispersal, and virulence. The alignment of the cell body with the surface during surface swimming impacts bacterial surface sensing. Here, we developed a high-throughput method for characterizing the orientation of the cell body relative to the surface using total internal reflection fluorescence (TIRF) microscopy. The angle between the cell body and the surface was determined by maximizing image cross-correlations between the TIRF image of the cell and a reference library. Utilizing this technique, we surprisingly identified six distinct surface swimming states of Pseudomonas aeruginosa according to the body alignment and the flagellar position. Furthermore, we observed that the near-surface swimming speed is greater in the pull state than in the push state, attributed to hydrodynamic effects near the liquid-solid interface. Hydrodynamic force analysis of the swimming states provided rich insights into the mechanics of bacterial surface swimming. Our technique is readily applicable to the study of surface motility across a wide spectrum of bacterial species.


Assuntos
Microscopia , Natação , Bactérias , Biofilmes , Pseudomonas aeruginosa
5.
Sci Adv ; 9(44): eadi6724, 2023 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-37922360

RESUMO

Flagellated bacteria, like Escherichia coli, swim by rotating helical flagellar filaments powered by rotary flagellar motors at their base. Motor dynamics are sensitive to the load it drives. It was previously thought that motor load was high when driving filament rotation in free liquid environments. However, torque measurements from swimming bacteria revealed substantially lower values compared to single-motor studies. We addressed this inconsistency through motor resurrection experiments, abruptly attaching a 1-micrometer-diameter bead to the filament to ensure high load. Unexpectedly, we found that the motor works with only half the complement of stator units when driving filament rotation. This suggests that the motor is not under high load during bacterial swimming, which we confirmed by measuring the torque-speed relationship by varying media viscosity. Therefore, the motor operates in an intermediate-load region, adaptively regulating its stator number on the basis of external load conditions. This ensures the robustness of bacterial motility when swimming in diverse load conditions and varying flagella numbers.


Assuntos
Proteínas Motores Moleculares , Natação , Bactérias , Escherichia coli/fisiologia , Flagelos/fisiologia , Proteínas de Bactérias
6.
iScience ; 26(10): 107950, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37817931

RESUMO

Bacteria perform chemotactic adaptation by sequential modification of multiple modifiable sites on chemoreceptors through stochastic action of tethered adaptation enzymes (CheR and CheB). To study the molecular kinetics of this process, we measured the response to different concentrations of MeAsp for the Tar-only Escherichia coli strain. We found a strong dependence of the methylation rate on the methylation level and established a new mechanism of adaptation kinetics due to tethered particle motion of the methylation enzyme CheR. Experiments with various lengths of the C-terminal flexible chain in the Tar receptor further validated this mechanism. The tethered particle motion resulted in a CheR concentration gradient that ensures encounter-rate matching of the sequential modifiable sites. An analytical model of multisite catalytic reaction showed that this enables robustness of methylation to fluctuations in receptor activity or cell-to-cell variations in the expression of adaptation enzymes and reduces the variation in methylation level among individual receptors.

7.
Maturitas ; 174: 57-66, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37295252

RESUMO

AIM: We performed a systematic review and meta-analysis to assess whether endometrial telomerase activity is associated with endometrial cancer or hyperplasia. METHODS: PubMed, Web of Science, Embase, Scielo, LILAC, and CNKI databases were searched to obtain relevant literature for articles published through June 2022, following PRISMA guidelines and a registered PROSPERO protocol. We included observational studies reporting endometrial telomerase activity in patients with either endometrial cancer or hyperplasia compared with benign endometrial tissue (control women). The Newcastle-Ottawa Scale was used to evaluate the quality of studies. Data were expressed as the odds ratios (OR) and 95 % confidence intervals (CI). Random effects and inverse variance methods were used to meta-analyze associations. The I2 test was used to assess heterogeneity. RESULTS: There were significant associations between endometrial telomerase activity and either endometrial cancer (20 studies, OR = 10.65, 95 % CI 6.39, 17.75, p = 0.00001, I2 = 21 %) or endometrial hyperplasia (nine studies, OR = 3.62, 95 % CI 1.61, 8.13, p = 0.002, I2 = 36 %) compared to women without endometrial cancer and hyperplasia. There was not a significant difference in telomerase activity in women with endometrial cancer compared to those with endometrial hyperplasia (seven studies, OR = 1.03; 95 % CI 0.31, 3.37, p = 0.96, I2 = 49 %). In subgroup analyses, there were no significant differences in telomerase activity in patients with endometrial cancer by type of observational studies and by countries of the studies. CONCLUSION: Endometrial telomerase activity is higher in women with either endometrial cancer or endometrial hyperplasia compared to control women without those lesions.


Assuntos
Hiperplasia Endometrial , Neoplasias do Endométrio , Telomerase , Feminino , Humanos , Hiperplasia Endometrial/genética , Neoplasias do Endométrio/genética , Endométrio , Hiperplasia
8.
Front Microbiol ; 14: 1159974, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37125196

RESUMO

In E. coli and related species, flagellar brake protein YcgR responds to the elevated intracellular c-di-GMP, decreases the flagellar rotation speed, causes a CCW rotation bias, and regulates bacterial swimming. Boehm et al. suggested that c-di-GMP-activated YcgR directly interacted with the motor protein MotA to curb flagellar motor output. Paul et al. proposed that YcgR disrupted the organization of the FliG C-terminal domain to bias the flagellar rotation. The target proteins are controversial, and the role of motor proteins remains unclear in flagellar rotation speed and direction regulation by YcgR. Here we assayed the motor proteins' affinity via a modified FRET biosensor and accessed the role of those key residue via bead assays. We found that YcgR could interact with both MotA and FliG, and the affinities could be enhanced upon c-di-GMP binding. Furthermore, residue D54 of YcgR-N was needed for FliG binding. The mutation of the FliG binding residue D54 or the MotA binding ones, F117 and E232, restored flagellar rotation speed in wild-type cells and cells lacking chemotaxis response regulator CheY that switched the flagellar rotation direction and decreased the CCW ratio in wild-type cells. We propose that c-di-GMP-activated YcgR regulated the flagellar rotation speed and direction via its interaction with motor proteins MotA and FliG. Our work suggest the role of YcgR-motor proteins interaction in bacterial swimming regulation.

9.
Phys Biol ; 20(4)2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37105184

RESUMO

The output of the bacterial chemotaxis signaling pathway, the level of the intracellular regulator CheY-P, modulates the rotation direction of the flagellar motor, thereby regulating bacterial run-and-tumble behavior. The multiple flagellar motors on anE. colicell are controlled by a common cytoplasmic pool of CheY-P. Fluctuation of the CheY-P level was thought to be able to coordinate the switching of multiple motors. Here, we measured the correlation of rotation directions between two motors on a cell, finding that it surprisingly exhibits two well separated timescales. We found that the slow timescale (∼6 s) can be explained by the slow fluctuation of the CheY-P level due to stochastic activity of the chemotactic adaptation enzymes, whereas the fast timescale (∼0.3 s) can be explained by the random pulse-like fluctuation of the CheY-P level, due probably to the activity of the chemoreceptor clusters. We extracted information on the properties of the fast CheY-P pulses based on the correlation measurements. The two well-separated timescales in the fluctuation of CheY-P level help to coordinate multiple motors on a cell and to enhance bacterial chemotactic performance.


Assuntos
Proteínas de Bactérias , Proteínas de Escherichia coli , Proteínas de Bactérias/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas Quimiotáticas Aceptoras de Metil/metabolismo , Escherichia coli/metabolismo , Flagelos/metabolismo , Proteínas de Membrana/metabolismo , Quimiotaxia/fisiologia
10.
Phys Rev Lett ; 130(13): 138401, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37067319

RESUMO

The bacterial hook, as a universal joint coupling rotation of the flagellar motor and the filament, is an important component of the flagellum that propels the bacteria to swim. The mechanical properties of the hook are essential for the flagellum to achieve normal functions. In multiflagellated bacteria such as Escherichia coli, the hook must be compliant so that it can bend for the filaments to form a coherently rotating bundle to generate the thrust when the motor rotates counterclockwise (CCW), yet it also must be rigid so that the bundle can disrupt for the bacteria to tumble to change swimming direction when the motor rotates clockwise (CW). Here, by combining an elastic rod model with high-resolution bead assay to accurately measure the bending stiffness of the hook under CCW or CW rotation in vivo, we elucidate how the hook accomplishes this dual functionality: the hook stiffens under CW rotation, with bending stiffness under CW rotation twice as large as that under CCW rotation. This enables a robust run-and-tumble swimming motility for multiflagellated bacteria.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Flagelos , Proteínas de Bactérias
11.
mBio ; 14(2): e0018923, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-36946730

RESUMO

The cytoplasmic ring (C-ring) of the bacterial flagellar motor controls the motor rotation direction, thereby controlling bacterial run-and-tumble behavior. The C-ring has been shown to undergo adaptive remodeling in response to changes in motor directional bias. However, the stoichiometry and arrangement of the C-ring is still unclear due to contradiction between the results from fluorescence studies and cryo-electron microscopy (cryo-EM) structural analysis. Here, by using the copy number of FliG molecules (34) in the C-ring as a reference, we precisely measured the copy numbers of FliM molecules in motors rotating exclusively counterclockwise (CCW) and clockwise (CW). We surprisingly found that there are on average 45 and 58 FliM molecules in CW and CCW rotating motors, respectively, which are much higher than previous estimates. Our results suggested a new mechanism of C-ring adaptation, that is, extra FliM molecules could be bound to the primary C-ring with probability depending on the motor rotational direction. We further confirmed that all of the FliM molecules in the C-ring function in chemotaxis signaling transduction because all of them could be bound by the chemotactic response regulator CheY-P. Our measurements provided new insights into the structure and arrangement of the flagellar switch. IMPORTANCE The bacterial flagellar switch can undergo adaptive remodeling in response to changes in motor rotation direction, thereby shifting its operating point to match the output of the chemotaxis signaling pathway. However, it remains unclear how the flagellar switch accomplishes this adaptive remodeling. Here, via precise fluorescence studies, we measured the absolute copy numbers of the critical component in the switch for motors rotating counterclockwise and clockwise, obtaining much larger numbers than previous relative estimates. Our results suggested a new mechanism of adaptive remodeling of the flagellar switch and provided new insights for updating the conformation spread model of the switch.


Assuntos
Proteínas de Bactérias , Flagelos , Proteínas de Bactérias/química , Microscopia Crioeletrônica , Flagelos/fisiologia , Proteínas Quimiotáticas Aceptoras de Metil/metabolismo , Quimiotaxia
12.
Ecotoxicol Environ Saf ; 253: 114671, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36822062

RESUMO

Hexafluoropropylene oxide tetramer acid (HFPO-TeA) is an emerging environmental contaminant, with environmental presence but limited toxicological information. To investigate its potential developmental toxicities, various doses of HFPO-TeA exposure were achieved in chicken embryos via air cell injection, and the exposed embryos were incubated until hatch. Within 24 h of hatch, the hatchling chickens were assessed with electrocardiography and histopathology for toxicological evaluation. For mechanistic investigation, in ovo silencing of PPARα was achieved via lentivirus microinjection, then the morphological/functional endpoints along with protein expression levels of PPARα-regulated genes were assessed. HFPO-TeA exposure in chicken embryo resulted in developmental cardiotoxicity and hepatotoxicity. Specifically, decreased right ventricular wall thickness, increased heart rate and hepatic steatosis were observed, whereas silencing of PPARα resulted in alleviation of observed toxicities. Western blotting for EHHADH and FABPs suggested that developmental exposure to HFPO-TeA effectively increased the expression levels of both targets in hatchling chicken heart and liver tissue samples, while PPARα silencing prevented such changes, suggesting that PPARα and its downstream genes are playing critical roles in HFPO-TeA induced developmental toxicities.


Assuntos
Galinhas , Fluorocarbonos , Embrião de Galinha , Animais , Galinhas/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , Fluorocarbonos/toxicidade , Coração , Fígado/metabolismo
13.
Food Funct ; 14(5): 2502-2517, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36815696

RESUMO

Background: L-carnitine supplementation has been utilized against glucolipid metabolism disruption. However, to the best of our knowledge, no meta-analysis process has analyzed the effects of L-carnitine supplementation on insulin resistance, fasting blood glucose, lipid metabolism, and liver enzyme levels in adults. Methods: Through the analysis and screening of 12 221 studies, 15 studies were selected from eligible trials for meta-analysis. Meta-analysis was performed in a random effect model with heterogeneity determined by I2, and subgroup analyses were used to further identify the source of heterogeneity. Result: The results showed significant effects of L-carnitine on FBG (MD = -4.94 mg dL-1, 95% CI: -7.07 to -2.82), insulin (MD = -0.99 µU mL-1, 95% CI: -1.41 to -0.56), HOMA-IR (MD = -0.58, 95% CI: -0.77 to -0.38), TG (MD = -11.22 mg dL-1, 95% CI: -19.21 to -3.22), TC (MD = -6.45 mg dL-1, 95% CI: -9.95 to -2.95, LDLc (MD = -8.28 mg dL-1, 95% CI: -11.08 to -5.47), and ALT (MD = -19.71 IU L-1, 95% CI: -36.45 to -2.96). However, no significant effect of L-carnitine supplementation was observed in HDLc (MD = -0.77 mg dL-1, 95% CI: -0.10 to -1.63) or AST (MD = -11.05 IU L-1, 95% CI: -23.08 to 0.99). The duration of carnitine supplementation was negatively associated with mean differences in FBG, as assessed by meta-regression. Conclusion: The current meta-analysis revealed that L-carnitine may have favorable effects on glucolipid profile, especially insulin, FBG, HOMA-IR, TG, TC, LDLc, and ALT levels.


Assuntos
Carnitina , Resistência à Insulina , Adulto , Humanos , Insulina , Suplementos Nutricionais
14.
Diabetes Metab Res Rev ; 39(4): e3612, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36656279

RESUMO

AIMS: This systematic review and meta-analysis examined maternal and cord blood betatrophin levels in pregnant women with gestational diabetes mellitus (GDM) and normoglycemic controls. MATERIAL AND METHODS: PubMed, Cochrane Library, Embase, LILACS, WangFang, and China National Knowledge Infrastructure were searched for literature from inception until May 2022. The primary outcomes were maternal and cord blood betatrophin levels. A random-effect meta-analysis was used to estimate the pooled results. The mean differences (MDs) or standardised MDs (SMD) and their 95% confidence intervals (CIs) were calculated. I2 tests were used to evaluate the heterogeneity. The quality of studies was evaluated using the Newcastle-Ottawa Scale. RESULTS: Betatrophin levels were reported in 22 studies with a total of 3034 pregnant women, and in seven studies including cord blood from 456 infants. Women with GDM display higher betatrophin levels than the normoglycemic controls (SMD = 0.85, 95% CI: 0.38-1.31) during the second half of the pregnancy. The sensitivity analysis indicated that no single study had significantly influenced the betatrophin overall outcomes. There was heterogeneity between the studies as evidenced by high I2 values. Meta-regression analysis indicated a significant regression coefficient for maternal betatrophin and glycosilated haemoglobin. There was no significant difference in cord blood betatrophin in infants from women with and without GDM (SMD = 0.34, 95% CI: -0.15-0.83). Women with GDM also had significantly higher insulin, glucose, glycosylated haemoglobin, HOMA-IR, LDL-cholesterol, HDL-cholesterol, triglycerides, and body mass index compared with the normoglycemic controls. CONCLUSIONS: Maternal betatrophin levels were higher in women with GDM than in the normoglycemic controls. There was no difference in cord blood betatrophin. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42022311372.


Assuntos
Diabetes Gestacional , Gravidez , Feminino , Humanos , Proteína 8 Semelhante a Angiopoietina , Gestantes , Sangue Fetal/metabolismo , Proteínas Semelhantes a Angiopoietina , Insulina/metabolismo
15.
Environ Pollut ; 317: 120722, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36436667

RESUMO

Perfluorooctanoic acid (PFOA) is a widespread persistent organic pollutant. Fertile chicken eggs were exposed to PFOA and incubated to hatch. At three time points post hatch (0-, 1- and 3-months old), chickens were subjected to electrocardiography and sacrificed. Serum was subjected to LC-MS/MS for PFOA concentration, and organs were subjected to histopathological assessments. Additionally, PPARα-silencing lentivirus was co-applied with PFOA exposure, and the corresponding phenotypes were evaluated. Western blotting was performed to assess expressions of FABPs and pSMAD2 in heart and liver samples. Considerable amount of PFOA were detected in hatchling chicken serum, but not in one-month-old or three-month-old chicken serum. PFOA exposure resulted in developmental cardiotoxicity and hepatotoxicity in hatchling chickens. Meanwhile, one-month-old chickens still exhibited elevated heart rate, but classical cardiac remodeling (thicker right ventricular wall) were observed in exposed animals. Three-month-old chickens exhibited similar results as one-month-old ones. PPARα silencing only had partial protective effects in hatchling chickens, but the protective effects seemed to increase as chickens aged. Western blotting results indicated that L-FABP was involved in PFOA-induced hepatotoxicity, while pSMAD2 was involved in PFOA-induced cardiotoxicity. In summary, developmental exposure to PFOA resulted in persistent cardiotoxicity, but not hepatotoxicity. PPARα participates in both cardiotoxicity and hepatotoxicity.


Assuntos
Galinhas , Fluorocarbonos , Animais , Galinhas/metabolismo , Cardiotoxicidade , PPAR alfa/genética , PPAR alfa/metabolismo , Cromatografia Líquida , Peroxissomos/metabolismo , Espectrometria de Massas em Tandem , Caprilatos/toxicidade , Caprilatos/metabolismo , Fluorocarbonos/toxicidade , Fluorocarbonos/metabolismo , Proliferação de Células , Fígado/metabolismo
16.
Appl Environ Microbiol ; 88(22): e0153922, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36286538

RESUMO

FliL is present in nearly all flagellated bacterial species and is associated with the flagellar basal body. This protein was found to be important for the function of the flagellar motor, and its absence led to a variety of motility defects in several species. However, the specific function of FliL in Pseudomonas aeruginosa remains elusive. Here, we studied the effects of FliL on motor output in P. aeruginosa using a bead assay, finding that FliL regulates motor output through its differential effects on the two sets of homologous MotAB and MotCD stators. FliL interacts with the MotCD stators to increase the motor torque and the stability of the motor speed, whereas it works with the MotAB stators to maintain a high motor switching rate. These effects of FliL contribute to enhancing P. aeruginosa's motility and chemotaxis. IMPORTANCE FliL emerged as a modulator of flagellar motor function in several bacterial species, but its function in Pseudomonas aeruginosa was unknown. Here, by performing single-motor studies using a bead assay, we elucidated its effects on the flagellar motor in P. aeruginosa. We found that it differentially interacts with two sets of stators (MotAB and MotCD) to regulate different aspects of bacterial motility (motor switching rate and motor rotation speed), thereby enhancing the ability of P. aeruginosa to explore its environment.


Assuntos
Flagelos , Pseudomonas aeruginosa , Pseudomonas aeruginosa/fisiologia , Flagelos/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Quimiotaxia
17.
Surg Obes Relat Dis ; 18(11): 1323-1338, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36058832

RESUMO

Obesity impairs cognition. Bariatric surgery can result in substantial weight loss in patients with severe obesity; however, the impact of bariatric surgery on cognitive function remains controversial. To quantify the effect of bariatric surgery on cognition in patients with severe obesity, we performed a meta-analysis of 20 studies retrieved from PubMed, Cochrane, and Embase. Of these, 6 cohort studies found that Roux-en-Y gastric bypass leads to better performance for immediate verbal memory function (standardized mean difference [SMD] = .56; 95% confidence interval [CI]: .30-.82, P < .0001; I2 = 0%) and delayed memory function (SMD = .64; 95% CI: .38-.90, P < .00001; I2 = 0%) during in the short term. Similarly, positive impacts on immediate verbal memory function (SMD = .46; 95% CI: .09-.83, P < .00001) and delayed memory function (SMD = .84; 95% CI: .46-1.22, P < .0001) were identified during a long-term follow-up. The Roux-en-Y gastric bypass group showed no improvements in attention, cognitive speed, and executive function compared with the control obese group. In 14 longitudinal studies (12 single-arm pre-post comparison studies and 2 cohort studies whose control group had no follow-up cognitive data), patients performed better postoperatively than preoperatively in all cognitive domains during repeated assessments. The analysis for the 20 operative groups showed that individuals treated with bariatric surgery had higher scores after repeated assessment of most neuropsychological tests except for animal fluency and letter fluency than baseline scores. These findings suggest that patients with severe obesity may obtain immediate verbal and delayed memory function benefits from Roux-en-Y gastric bypass.


Assuntos
Cirurgia Bariátrica , Derivação Gástrica , Obesidade Mórbida , Humanos , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Resultado do Tratamento , Obesidade/cirurgia , Cognição
18.
World J Gastrointest Surg ; 14(8): 778-787, 2022 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-36157373

RESUMO

BACKGROUND: The prevalence of constipation in the Chinese population over 60 years of age is 11.5%, and this prevalence increases with age, which seriously affects the quality of life in older adults. Therefore, reducing the incidence of constipation in older adults is necessary to promote a healthy lifestyle as well as biochemical health. AIM: To explore the value of preoperative guidance and education to improve the effects of bowel cleaning in older adult patients undergoing colonoscopy. METHODS: In this study, 160 older adult patients with constipation requiring colonoscopy at Shandong Provincial Hospital between January 2019 and March 2021 were selected and randomly divided into a study group and a control group, with 80 patients in each group. The study group received medication guidance and targeted educational guidance before the operation, while the control group received only medication and dietary guidance. The baseline data, colonoscopy duration, bowel preparation compliance, Boston bowel preparation (BBPS) assessment score, intestinal bubble score, the incidence of adverse reactions during bowel preparation, and nursing appointment satisfaction were compared between the two groups. RESULTS: The colonoscopy duration times and intestinal bubble scores of the study group were shorter than those of the control group, with statistically significant differences. The BBPS scores for the right, left, and interrupted colon in the study group were also higher than those in the control group, and the difference was statistically significant. Additionally, the study group had a higher rate of liquid diet one day before the examination, higher rate of correct bowel-clearing agent dilution method, higher rate of accurate time of ingesting the bowel-clearing agent, and a higher proportion of patients ingesting bowel-clearing agent at the specified time than the control group, with statistically significant differences. The incidence of nausea and vomiting during bowel clearance in the study group was significantly lower than that in the control group. The incidence of abdominal pain, abdominal distension, dizziness, and fatigue was compared between the two groups, but the difference was not statistically significant. The scores of service attitude, detailed notification of dietary precautions, clear and easy-to-understand health educational content, and receiving care and comfort in the study group were significantly higher than those in the control group. CONCLUSION: Preoperative special guidance and education were shown to significantly improve bowel clearance and compliance and reduce the incidence of adverse reactions in older adult patients with constipation undergoing colonoscopy. These factors are beneficial for improving patient satisfaction with nursing services.

19.
Environ Pollut ; 312: 120022, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36028080

RESUMO

Perfluorooctanoic acid (PFOA) could induce developmental toxicities, affecting various organs, including the heart. Although peroxisome-proliferation activated receptor alpha (PPARα) had been identified as a major target of PFOA, PPARα-independent effects are frequently reported. To further elucidate the mechanism of toxicity in PFOA-induced developmental cardiotoxicity, RNA-seq analysis was performed in hatchling chicken hearts developmentally exposed to vehicle or 2 mg/kg (egg weight) PFOA. RT-PCR and western blotting were then performed to confirm the identified potential targets. Furthermore, lentivirus was designed to overexpress and silence identified target miRNA in developing chicken embryo, and the resulting phenotypes were investigated. 21 miRNAs and 1142 mRNAs were identified to be affected by developmental exposure to PFOA in chicken embryo hearts. Among the identified differentially expressed miRNAs, miR-490-5p was confirmed to be significantly affected by PFOA exposure, along with its downstream targets, Synaptosome associated protein 91 (SNAP91) and LY6/PLAUR domain containing 6 (LYPD6), as indicated by RT-PCR and western blotting results. Lentivirus overexpressing miR-490-5p mimicked the phenotype induced by PFOA exposure, while lentivirus silencing miR-490-5p alleviated PFOA-induced changes. Similar patterns were also observed in the expression of downstream target genes, SNAP91 and LYPD6. In summary, miR-490-5p and its downstream genes, SNAP91 and LYPD6 are associated with PFOA-induced developmental cardiotoxicity in chicken embryo, which might help to further elucidate the mechanism of PFOA-induced developmental cardiotoxicity.


Assuntos
Fluorocarbonos , MicroRNAs , Animais , Caprilatos , Cardiotoxicidade , Embrião de Galinha , Galinhas/metabolismo , Fluorocarbonos/metabolismo , Fluorocarbonos/toxicidade , MicroRNAs/genética , MicroRNAs/metabolismo , PPAR alfa/metabolismo
20.
Front Microbiol ; 13: 928408, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35875555

RESUMO

The evolution of the bacterial flagellum gave rise to motility and repurposing of a signaling network, now termed the chemotaxis network, enabled biasing of cell movements. This made it possible for the bacterium to seek out favorable chemical environments. To enable chemotaxis, the chemotaxis network sensitively detects extracellular chemical stimuli and appropriately modulates flagellar functions. Additionally, the flagellar motor itself is capable of detecting mechanical stimuli and adapts its structure and function in response, likely triggering a transition from planktonic to surface-associated lifestyles. Recent work has shown a link between the flagellar motor's response to mechanical stimuli and the chemotactic output. Here, we elaborate on this link and discuss how it likely helps the cell sense and adapt to changes in its swimming speeds in different environments. We discuss the mechanism whereby the motor precisely tunes its chemotaxis output under different mechanical loads, analogous to proprioception in higher order organisms. We speculate on the roles bacterial proprioception might play in a variety of phenomena including the transition to surface-associated lifestyles such as swarming and biofilms.

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