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1.
Int J Obes (Lond) ; 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38228876

RESUMEN

BACKGROUND: Obesity (OB) is highly prevalent in females after menopause, especially visceral adipose tissue (VAT) accumulation which contributes to endothelial dysfunction. The endothelium assists in regulating blood flow (BF) during exercise and is attenuated in females with OB. The purpose of this study was to examine upper and lower limb flow-mediated dilation (FMD) and BF regulation during graded low-intensity submaximal exercises in postmenopausal females with BMI in the lean (LN), overweight (OW) and OB categories. METHODS: Participants were grouped by body mass index (BMI) into LN (BMI 18.5-24.9 kg/m2; n = 11), OW (BMI 25.0-29.9 kg/m2; n = 15), and OB (BMI 30.0-39.9 kg/m2; n = 13). FMD of the brachial (BA-FMD) and superficial femoral arteries (FA-FMD) were assessed. Subsequently, BF and vascular conductance (VC) in the upper (BA-BF and BA-VC) and lower limbs (FA-BF and FA-VC) were measured during separate 3-stage incremental rhythmic handgrip and plantarflexion exercises. RESULTS: Significantly lower FA-FMD (P < 0.05) were seen in OB than LN and OW groups with no differences in BA-FMD. Increases in FA-BF and FA-VC were attenuated during the last stage of plantarflexion exercise at 30% of 1RM in OB (both P < 0.001) compared to LN and OW, while upper-body exercise vasodilation was unchanged. FA-BF and FA-VC during plantarflexion exercise were correlated to FA-FMD (FA-BF: r = 0.423, P = 0.007, FA-VC: r = 0.367, P = 0.021) and BMI (FA-BF: r = -0.386, P = 0.015, FA-VC: r = -0.456, P = 0.004). CONCLUSION: Postmenopausal females with OB have reduced lower-limb endothelial and exercise vasodilator function during submaximal dynamic plantarflexion exercise compared to LN and OW. Our findings indicate that obesity may predict diminished leg endothelial function, BF and VC during exercise in postmenopausal females.

2.
Br J Nutr ; 131(3): 474-481, 2024 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-37664994

RESUMEN

Postmenopausal women have augmented pressure wave responses to low-intensity isometric handgrip exercise (IHG) due to an overactive metaboreflex (postexercise muscle ischaemia, PEMI), contributing to increased aortic systolic blood pressure (SBP). Menopause-associated endothelial dysfunction via arginine (ARG) and nitric oxide deficiency may contribute to exaggerated exercise SBP responses. L-Citrulline supplementation (CIT) is an ARG precursor that decreases SBP, pulse pressure (PP) and pressure wave responses to cold exposure in older adults. We investigated the effects of CIT on aortic SBP, PP, and pressure of forward (Pf) and backward (Pb) waves during IHG and PEMI in twenty-two postmenopausal women. Participants were randomised to CIT (10 g/d) or placebo (PL) for 4 weeks. Aortic haemodynamics were assessed via applanation tonometry at rest, 2 min of IHG at 30 % of maximal strength, and 3 min of PEMI. Responses were analysed as change (Δ) from rest to IHG and PEMI at 0 and 4 weeks. CIT attenuated ΔSBP (−9 ± 2 v. −1 ± 1 mmHg, P = 0·006), ΔPP (−5 ± 2 v. 0 ± 1 mmHg, P = 0·03), ΔPf (−6 ± 2 v. −1 ± 1 mmHg, P = 0·01) and ΔPb (−3 ± 1 v. 0 ± 1 mmHg, P = 0·02) responses to PEMI v. PL. The ΔPP during PEMI was correlated with ΔPf (r = 0·743, P < 0·001) and ΔPb (r = 0·724, P < 0·001). Citrulline supplementation attenuates the increase in aortic pulsatile load induced by muscle metaboreflex activation via reductions in forward and backward pressure wave amplitudes in postmenopausal women.


Asunto(s)
Presión Arterial , Citrulina , Humanos , Femenino , Anciano , Presión Arterial/fisiología , Citrulina/farmacología , Posmenopausia , Fuerza de la Mano , Músculo Esquelético , Presión Sanguínea , Suplementos Dietéticos
3.
Eur J Appl Physiol ; 124(9): 2603-2613, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38607608

RESUMEN

PURPOSE: Postmenopausal women experience augmented aortic hemodynamic responses to isometric handgrip (IHG) exercise and metaboreflex activation post-exercise muscle ischemia (PEMI). Relationships between endothelial function brachial artery flow-mediated dilation (FMD) and aortic stiffness carotid-femoral pulse wave velocity (cfPWV) with aortic pulsatile hemodynamics during IHG and PEMI have not been determined. The relationships between aortic hemodynamic responses to PEMI were evaluated. METHODS: Aortic blood pressure (BP), wave reflection, and pressure of forward (Pf) and backward (Pb) waves were measured using arterial tonometry at rest, IHG at 30% maximal force, and PEMI in 30 (15/group) postmenopausal women with low (≤ 4.5%) and normal (≥ 5.5%) FMD. Hemodynamic responses were analyzed as the change (Δ) from rest to the last minute of IHG and PEMI. RESULTS: Brachial and aortic systolic BP (SBP) responses to IHG were higher in the low vs normal FMD group (P < 0.05). Aortic SBP (Δ20 ± 8 vs Δ11 ± 7 mmHg), pulse pressure (PP) (Δ12 ± 8 vs Δ6 ± 4 mmHg), augmented pressure (AP) (Δ5 ± 3 vs Δ2 ± 2 mmHg), and Pb (Δ6 ± 4 vs Δ3 ± 2 mmHg) responses to PEMI were greater (P < 0.05) in women with low vs. normal FMD. FMD was negatively correlated with aortic SBP, PP, AP, and Pb (P < 0.05) responses to PEMI. cfPWV was not correlated with responses to PEMI. CONCLUSION: Endothelial dysfunction relates to augmented aortic pulsatile load during metaboreflex activation, which may increase cardiovascular risk in postmenopausal women.


Asunto(s)
Aorta , Endotelio Vascular , Posmenopausia , Humanos , Femenino , Posmenopausia/fisiología , Persona de Mediana Edad , Endotelio Vascular/fisiopatología , Endotelio Vascular/fisiología , Endotelio Vascular/metabolismo , Aorta/fisiopatología , Aorta/fisiología , Fuerza de la Mano/fisiología , Reflejo/fisiología , Presión Sanguínea/fisiología , Ejercicio Físico/fisiología , Hemodinámica/fisiología , Vasodilatación/fisiología , Anciano , Rigidez Vascular/fisiología , Músculo Esquelético/fisiología , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatología , Arteria Braquial/fisiología , Arteria Braquial/fisiopatología
4.
Alcohol Clin Exp Res ; 42(2): 260-269, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29121399

RESUMEN

BACKGROUND: It is widely assumed that the amount of alcohol in the blood reflects the amount of alcohol consumed. However, several factors in addition to amount of alcohol consumed can influence blood alcohol concentration (BAC). This study examines the effect of alcohol dose, concentration, and volume on BAC in rats with a high-alcohol-drinking (HAD) phenotype. METHODS: Study 1 examined the relationship between the amount of alcohol consumed and BAC. Alcohol-naïve, male, HAD rats (N = 7) were given access to alcohol for 2 h/d for 9 consecutive days with food and water ad libitum. Alcohol intake and BAC were measured at 30, 60, and 90 minutes after onset of access. Study 2 examined the effects of altering alcohol dose, concentration, and volume on BAC (as measured by area under the curve). Alcohol-naïve, male, HAD rats (N = 39) were infused, via an intragastric cannulus, with 1.16, 2.44, or 3.38 g alcohol/kg body weight (BW), produced by varying alcohol volume while holding concentration constant or by holding volume constant while varying concentration. Other rats were infused with 10, 15, or 20% v/v alcohol solutions while holding dose constant. RESULTS: BAC was more strongly correlated with the ratio of alcohol intake (g/kg BW) to total fluid intake (mls) (R = 0.85 to 0.97, p < 0.05 to p < 0.001) than it was with the amount of alcohol consumed (g/kg BW) (R = 0.70 to 0.81, p < 0.05). No effect of alcohol dose was seen during the first hour following the onset of an alcohol infusion regardless of whether dose was achieved by altering alcohol volume or concentration. After 1 hour, higher alcohol doses were predictive of greater BACs. CONCLUSIONS: The fact that a 3-fold difference in alcohol dose did not result in significant differences in BACs during the first 30 minutes after ingestion of alcohol has potentially important implications for interpretation of studies that measure alcohol-sensitive end points during this time.


Asunto(s)
Consumo de Bebidas Alcohólicas/sangre , Nivel de Alcohol en Sangre , Depresores del Sistema Nervioso Central/farmacocinética , Etanol/farmacocinética , Animales , Depresores del Sistema Nervioso Central/sangre , Etanol/sangre , Masculino , Ratas
5.
Alcohol Clin Exp Res ; 41(3): 644-652, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28055135

RESUMEN

BACKGROUND: This study examined whether naltrexone (NTX) or varenicline (VAR), alone or in combination, can retard the phenotypic expression of a genetic predisposition toward high alcohol drinking in rats selectively bred for high alcohol intake when drug treatment is initiated prior to, or concomitantly with, the onset of alcohol drinking. METHODS: Alcohol-naïve P rats were treated daily with NTX (15.0 mg/kg BW), VAR (1.0 mg/kg BW), a combination of NTX (15.0 mg/kg BW) + VAR (1.0 mg/kg BW), or vehicle (VEH) for 2 weeks prior to, or concomitantly with, their first opportunity to drink alcohol and throughout 21 days of daily 2-hour alcohol access. Drug treatment was then discontinued for 3 weeks followed by reinstatement of drug treatment for an additional 3 weeks. RESULTS: When P rats were pretreated with drug for 2 weeks prior to onset of alcohol access, only NTX + VAR in combination blocked the acquisition of alcohol drinking in alcohol-naïve P rats. When drug treatment was initiated concomitantly with the first opportunity to drink alcohol, NTX alone, VAR alone, and NTX + VAR blocked the acquisition of alcohol drinking. Following termination of drug treatment, NTX + VAR and VAR alone continued to reduce alcohol drinking but by the end of 3 weeks without drug treatment, alcohol intake in all groups was comparable to that seen in the vehicle-treated group as the expression of a genetic predisposition toward high alcohol drinking emerged in the drug-free P rats. After 3 weeks without drug treatment, reinstatement of NTX + VAR treatment again reduced alcohol intake. CONCLUSIONS: A combination of NTX + VAR, when administered prior to, or concomitantly with, the first opportunity to drink alcohol, blocks the acquisition of alcohol drinking during both initial access to alcohol and during a later period of alcohol access in P rats with a genetic predisposition toward high alcohol intake. The results suggest that NTX + VAR may be effective in curtailing alcohol drinking in individuals at high genetic risk of developing alcoholism.


Asunto(s)
Consumo de Bebidas Alcohólicas/tratamiento farmacológico , Consumo de Bebidas Alcohólicas/genética , Predisposición Genética a la Enfermedad/genética , Naltrexona/administración & dosificación , Vareniclina/administración & dosificación , Animales , Quimioterapia Combinada , Masculino , Antagonistas de Narcóticos/administración & dosificación , Agonistas Nicotínicos/administración & dosificación , Ratas
6.
Transfusion ; 56(1): 170-8, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26467770

RESUMEN

BACKGROUND: Platelet (PLT) transfusion is the primary treatment for thrombocytopenia. PLTs are obtained exclusively from volunteer donors, and the PLT product has only a 5-day shelf life, which can limit supply and result in PLT shortages. PLTs derived from stem cells could help to fill this clinical need. However, current culture methods yield far too few PLTs for clinical application. To address this need, a defined, serum-free culture method was designed using a novel bioreactor to increase the yield of PLTs from stem cell-derived megakaryocytes. STUDY DESIGN AND METHODS: CD34 cells isolated from umbilical cord blood were expanded with a variety of reagents and on a nanofiber membrane using serum-free medium. These cells were then differentiated into megakaryocytic lineage by culturing with thrombopoietin and stem cell factor in serum-free conditions. Polyploidy was induced by addition of Rho kinase inhibitor or actin polymerization inhibitor to the CD41 cells. A novel bioreactor was developed that recapitulated aspects of the marrow vascular niche. Polyploid megakaryocytes that were subjected to flow in the bioreactor extended proPLTs and shed PLTs, as confirmed by light microscopy, fluorescence imaging, and flow cytometry. RESULTS: CD34 cells were expanded 100-fold. CD41 cells were expanded 100-fold. Up to 100 PLTs per input megakaryocyte were produced from the bioreactor, for an overall yield of 10(6) PLTs per input CD34 cell. The PLTs externalized P-selectin after activation. DISCUSSION: Functional PLTs can be produced ex vivo on a clinically relevant scale using serum-free culture conditions with a novel stepwise approach and an innovative bioreactor.


Asunto(s)
Reactores Biológicos , Plaquetas/fisiología , Técnicas de Cultivo de Célula/instrumentación , Diferenciación Celular , Sangre Fetal/citología , Células Madre Hematopoyéticas/fisiología , Transfusión de Plaquetas , Técnicas de Cultivo de Célula/métodos , Células Cultivadas , Medio de Cultivo Libre de Suero , Citometría de Flujo , Humanos , Megacariocitos/fisiología
7.
Alcohol Clin Exp Res ; 40(9): 1961-70, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27469281

RESUMEN

BACKGROUND: This study examined whether varenicline (VAR), or naltrexone (NTX), alone or in combination, reduces alcohol drinking in alcohol-preferring (P) rats with a genetic predisposition toward high voluntary alcohol intake. METHODS: Alcohol-experienced P rats that had been drinking alcohol (15% v/v) for 2 h/d for 4 weeks were fed either vehicle (VEH), VAR alone (0.5, 1.0, or 2.0 mg/kg body weight [BW]), NTX alone (10.0, 15.0, or 20.0 mg/kg BW), or VAR + NTX in 1 of 4 dose combinations (0.5 VAR + 10.0 NTX, 0.5 VAR + 15.0 NTX, 1.0 VAR + 10.0 NTX, or 1.0 VAR + 15.0 NTX) at 1 hour prior to alcohol access for 10 consecutive days, and the effects on alcohol intake were assessed. RESULTS: When administered alone, VAR in doses of 0.5 or 1.0 mg/kg BW did not alter alcohol intake but a dose of 2.0 mg/kg BW decreased alcohol intake. This effect disappeared when drug treatment was terminated. NTX in doses of 10.0 and 15.0 mg/kg BW did not alter alcohol intake but a dose of 20.0 mg/kg BW decreased alcohol intake. Combining low doses of VAR and NTX into a single medication reduced alcohol intake as well as did high doses of each drug alone. Reduced alcohol intake occurred immediately after onset of treatment with the combined medication and continued throughout prolonged treatment. CONCLUSIONS: Low doses of VAR and NTX, when combined in a single medication, reduce alcohol intake in a rodent model of alcoholism. This approach has the advantage of reducing potential side effects associated with each drug. Lowering the dose of NTX and VAR in a combined treatment approach that maintains efficacy while reducing the incidence of negative side effects may increase patient compliance and improve clinical outcomes for alcoholics and heavy drinkers who want to reduce their alcohol intake.


Asunto(s)
Consumo de Bebidas Alcohólicas/tratamiento farmacológico , Alcoholismo/tratamiento farmacológico , Modelos Animales , Naltrexona/administración & dosificación , Antagonistas de Narcóticos/administración & dosificación , Vareniclina/administración & dosificación , Consumo de Bebidas Alcohólicas/psicología , Alcoholismo/psicología , Animales , Relación Dosis-Respuesta a Droga , Quimioterapia Combinada , Masculino , Agonistas Nicotínicos/administración & dosificación , Ratas , Roedores , Resultado del Tratamiento
9.
Alcohol Clin Exp Res ; 39(8): 1538-46, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26207767

RESUMEN

BACKGROUND: Many alcoholics and heavy drinkers undergo repeated cycles of alcohol abstinence followed by relapse to alcohol drinking; a pattern that contributes to escalated alcohol intake over time. In rodents, alcohol drinking that is interspersed with periods of alcohol deprivation (imposed abstinence) increases alcohol intake during reaccess to alcohol. This is termed the "alcohol deprivation effect" or "ADE" and is a model of alcohol relapse in humans. We have previously reported that prazosin reduces alcohol drinking during both brief and prolonged treatment in rats selectively bred for alcohol preference ("P" rats). This study explores whether prazosin prevents alcohol "relapse" in P rats, as reflected by a reduced or abolished ADE. METHODS: Adult male P rats were given 24-hour access to food and water and scheduled access to alcohol (15 and 30% v/v solutions presented concurrently) for 2 h/d. After 5 weeks, rats underwent imposed alcohol deprivation for 2 weeks, followed by alcohol reaccess for 2 weeks, and this pattern was repeated for a total of 3 cycles. Rats were injected with prazosin (0, 0.5, 1.0, or 2.0 mg/kg body weight, intraperitoneally) once a day for the first 5 days of each alcohol reaccess cycle. RESULTS: Alcohol intake increased on the first day of each alcohol reaccess cycle, demonstrating the formation of an ADE. The ADE was short-lived, lasting only 1 day, during each of the 3 cycles. Prazosin, in all doses tested, prevented the expression of an ADE in all 3 alcohol reaccess cycles. CONCLUSIONS: Prazosin decreases alcohol intake in P rats even in a situation that would be expected to increase alcohol drinking, namely following periods of alcohol deprivation. This suggests that prazosin may be effective in reducing alcohol relapse that often occurs during attempts to achieve permanent alcohol abstinence in treatment-seeking alcoholics and heavy drinkers.


Asunto(s)
Abstinencia de Alcohol , Consumo de Bebidas Alcohólicas/tratamiento farmacológico , Alcoholismo/tratamiento farmacológico , Modelos Animales de Enfermedad , Prazosina/uso terapéutico , Consumo de Bebidas Alcohólicas/psicología , Alcoholismo/psicología , Animales , Masculino , Ratas , Recurrencia
10.
Nutrients ; 16(12)2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38931289

RESUMEN

Endothelial dysfunction decreases exercise limb blood flow (BF) and muscle oxygenation. Acute L-Citrulline supplementation (CIT) improves muscle tissue oxygen saturation index (TSI) and deoxygenated hemoglobin (HHb) during exercise. Although CIT improves endothelial function (flow-mediated dilation [FMD]) in hypertensive women, the impact of CIT on exercise BF and muscle oxygenation (TSI) and extraction (HHb) are unknown. We examined the effects of CIT (10 g/day) and a placebo for 4 weeks on blood pressure (BP), arterial vasodilation (FMD, BF, and vascular conductance [VC]), and forearm muscle oxygenation (TSI and HHb) at rest and during exercise in 22 hypertensive postmenopausal women. Compared to the placebo, CIT significantly (p < 0.05) increased FMD (Δ-0.7 ± 0.6% vs. Δ1.6 ± 0.7%) and reduced aortic systolic BP (Δ3 ± 5 vs. Δ-4 ± 6 mmHg) at rest and improved exercise BF (Δ17 ± 12 vs. Δ48 ± 16 mL/min), VC (Δ-21 ± 9 vs. Δ41 ± 14 mL/mmHg/min), TSI (Δ-0.84 ± 0.58% vs. Δ1.61 ± 0.46%), and HHb (Δ1.03 ± 0.69 vs. Δ-2.76 ± 0.77 µM). Exercise BF and VC were positively correlated with improved FMD and TSI during exercise (all p < 0.05). CIT improved exercise artery vasodilation and muscle oxygenation via increased endothelial function in hypertensive postmenopausal women.


Asunto(s)
Citrulina , Suplementos Dietéticos , Ejercicio Físico , Fuerza de la Mano , Hipertensión , Músculo Esquelético , Posmenopausia , Flujo Sanguíneo Regional , Vasodilatación , Humanos , Femenino , Citrulina/farmacología , Persona de Mediana Edad , Hipertensión/fisiopatología , Hipertensión/tratamiento farmacológico , Músculo Esquelético/metabolismo , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/irrigación sanguínea , Fuerza de la Mano/fisiología , Vasodilatación/efectos de los fármacos , Flujo Sanguíneo Regional/efectos de los fármacos , Anciano , Ejercicio Físico/fisiología , Presión Sanguínea/efectos de los fármacos , Oxígeno/sangre , Oxígeno/metabolismo , Consumo de Oxígeno/efectos de los fármacos , Método Doble Ciego , Endotelio Vascular/efectos de los fármacos
11.
Tob Induc Dis ; 222024.
Artículo en Inglés | MEDLINE | ID: mdl-39072280

RESUMEN

INTRODUCTION: Among women at risk for alcohol-exposed pregnancies (AEP), smoking tobacco may be associated with increased severity of alcohol use, and risk for tobacco-exposed and other substance-exposed pregnancies (TEPs/SEPs). Our secondary data analysis of the 'CHOICES Plus' intervention trial explored AEP and SEP risk by smoking status. METHODS: Eligible women (N=261) were recruited from 12 primary care clinics in a public healthcare system, not pregnant, aged 18-44 years, drinking >3 drinks/day or >7 drinks/week, sexually active, and not using effective contraception. We compared women who did and did not smoke tobacco on alcohol and drug severity, and psychological distress (e.g. anxiety) at baseline. RESULTS: Participants were primarily Hispanic (47.1%) or non-Hispanic Black (41.8%) and reported incomes <$20000/year (69.3%). Tobacco smoking prevalence was 45.2%. Compared to non-smokers, those who smoked drank more days/week (mean=3.3, SD=2.0 vs mean=2.7, SD=1.8, p<0.01), had higher alcohol use disorders identification test (AUDIT) scores (mean=12.1, SD=7.6 vs mean=9.8, SD=7.1, p<0.05), were more likely to report current drug use (66.1% vs 48.3%, p<0.01), and had a greater number of (lifetime) drugs used (mean=3.0, SD=2.0 vs mean=2.0, SD=1.5 days, p<0.0001). Also, those who smoked reported greater levels of anxiety (mean=5.9, SD=5.6 vs mean=4.5, SD=4.9, p<0.05), lower confidence to not drink (mean=2.8, SD=0.8 vs mean=3.1, SD=1.0, p<0.01), lower confidence to reduce risky drinking (mean=6.3, SD=3.1 vs mean=7.3, SD=2.8, p<0.0001), greater drinking temptations (mean=3.0, SD=0.9 vs mean=2.6, SD=0.9, p<0.01), and, yet greater readiness to reduce alcohol use (mean=6.2, SD=3.0 vs mean=5.2, SD=3.0, p<0.05). CONCLUSIONS: Women who drink and smoke may have the highest AEP, TEP, and other SEP risk. Primary care providers should screen for alcohol and tobacco co-use and provide brief intervention and/or treatment referral. CLINICAL TRIAL REGISTRATION: The study was registered on the official website of ClinicalTrials.gov. IDENTIFIER: ID NCT01032772.

12.
ACS Appl Mater Interfaces ; 16(21): 27908-27916, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38752559

RESUMEN

Biofouling is a serious issue affecting the marine industry because the attached micro- and macrocontaminants can increase fuel consumption and damage ship hulls. A hydrophilic hydrogel-based coating is considered a promising antifouling material because it is environmentally friendly and the dense hydration layer can protect the substrate from microbial attachment. However, sediment adsorption can be an issue for hydrogel-based coatings. Their natural soft and porous structures can trap sediment from the marine environment and weaken the antifouling capability. There is still little research on the antisediment properties of hydrogels, and none of them deal with this problem. Here, we report on optimizing zwitterionic hydrogel-based coatings to improve their antisediment properties and achieve comparable performance to commercial biocidal coatings, which are the gold standard in the antifouling coating area. After 1 week of sediment contamination and 2 weeks of diatom coculturing, this optimized zwitterionic hydrogel coating maintained its antifouling properties with a few diatoms on the surface. Its large-scale samples also achieved antifouling performance similar to that of biocidal coatings in the Atlantic Ocean for 1.5 months. More importantly, our research provides a universal strategy to improve the antisediment properties of soft hydrogel-based coatings. For the first time, we report that the introduction of interfacial electrostatic interactions enhanced the antisediment properties of hydrogels.

13.
Alcohol Clin Exp Res ; 37(9): 1552-60, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23731093

RESUMEN

BACKGROUND: This study examined whether prazosin reduces alcohol drinking over the course of prolonged treatment and whether it blocks the initiation of alcohol drinking in rats with a genetic predisposition toward high alcohol drinking, that is alcohol-preferring (P) rats. METHODS: In study one, alcohol-experienced P rats that had been drinking alcohol for 2 h/d for several months were treated daily with prazosin (0, 0.5, 1.0, or 2.0 mg/kg body weight [BW]) for 7 weeks. In study two, alcohol-naïve P rats were treated daily with prazosin (0, 1.0, or 2.0 mg/kg BW) for 2 weeks prior to, or concomitantly with, the initiation of alcohol access and throughout 3 weeks of alcohol availability. Prazosin treatment and alcohol access were then discontinued for 2 weeks followed by reinstatement of alcohol access without prazosin treatment for 4 weeks, followed by resumption of daily prazosin treatment (2.0 mg/kg BW) for 3 weeks. RESULTS: Prazosin reduced alcohol drinking throughout 7 weeks of treatment in P rats accustomed to drinking alcohol. Following termination of prazosin treatment, alcohol drinking slowly returned to pretreatment baseline. Reduced alcohol intake was accompanied by increased water intake. In alcohol-naïve P rats, prazosin administration prior to the first opportunity to drink alcohol and throughout 3 weeks of alcohol access retarded acquisition of alcohol drinking and reduced the amount of alcohol consumed. When prazosin was administered concomitantly with the first opportunity to drink alcohol, it abolished acquisition of alcohol drinking. Discontinuation of prazosin treatment allowed expression of a genetic predisposition toward high alcohol drinking to gradually emerge. Prazosin retained the ability to reduce alcohol intake with repeated treatments. CONCLUSIONS: Prazosin decreased alcohol drinking during prolonged treatment and may be useful for treating alcoholism and alcohol-use disorders. Prazosin may also be useful for deterring the initiation of drinking in individuals with a family history of alcoholism.


Asunto(s)
Consumo de Bebidas Alcohólicas/tratamiento farmacológico , Consumo de Bebidas Alcohólicas/genética , Cruzamiento , Etanol/administración & dosificación , Prazosina/administración & dosificación , Animales , Cruzamiento/métodos , Relación Dosis-Respuesta a Droga , Masculino , Distribución Aleatoria , Ratas , Factores de Tiempo , Resultado del Tratamiento
14.
Nutrients ; 15(7)2023 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-37049398

RESUMEN

Postmenopausal women (PMW) may experience endothelial dysfunction associated with arginine (ARG) deficiency relative to asymmetric dimethylarginine (ADMA) caused by oxidative stress. Endothelial dysfunction contributes to increased blood pressure (BP) responsiveness to sympathoexcitation induced by the cold pressor test (CPT). We investigated the effects of citrulline alone (CIT) and combined with the antioxidant glutathione (CIT+GSH) on vascular function. Forty-four healthy PMW were randomized to CIT (6 g), CIT+GSH (2 g + 200 mg: Setria®) or placebo (PL) for 4 weeks. Brachial artery flow-mediated dilation (FMD), aortic stiffness (pulse wave velocity, PWV), brachial and aortic BP reactivity to CPT, and serum fasting blood glucose (FBG), ARG, and ARG/ADMA ratio were measured. Baseline FBG was higher in CIT+GSH vs. PL. FMD increased after CIT+GSH vs. PL (p < 0.05). CIT and CIT+GSH increased ARG/ADMA (p < 0.05), but did not affect aortic PWV. CIT+GSH attenuated the brachial and aortic systolic BP and mean arterial pressure (MAP) responses to CPT vs. PL and CIT (p < 0.05). The improvements in FMD were related to baseline FMD (r = -0.39, p < 0.05) and aortic MAP response to CPT (r = -0.33, p < 0.05). This study showed that CIT+GSH improved FMD and attenuated systolic BP and MAP reactivity in PMW. Although CIT increased ARG/ADMA, it did not improve FMD in healthy PMW.


Asunto(s)
Citrulina , Enfermedades Vasculares , Humanos , Femenino , Presión Sanguínea , Citrulina/farmacología , Análisis de la Onda del Pulso , Posmenopausia , Glutatión , Suplementos Dietéticos , Arginina , Endotelio Vascular
15.
Menopause ; 29(12): 1423-1429, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36194846

RESUMEN

OBJECTIVE: Postmenopausal women (post-MW) have greater risk of heart failure due to aortic pulsatile overload on the left ventricle associated with increased backward wave pressure (Pb). Post-MW have exaggerated peripheral blood pressure (BP) response to exercise mediated by metaboreflex (postexercise muscle ischemia [PEMI]) overactivation. Increased forward wave pressure (Pf) and Pb are determinants of aortic pulse pressure (PP) during isometric handgrip exercis (IHG) in young adults. We hypothesized that aortic PP and pressure wave responses to PEMI are augmented in nonhypertensive post-MW compared with premenopausal women (pre-MW). METHODS: Aortic BP, Pf, Pb, and reflection magnitude were assessed at rest and during IHG and PEMI by applanation tonometry in 15 pre-MW and 16 post-MW. RESULTS: Aortic systolic BP during PEMI similarly increased in both groups. The increase in diastolic BP was lower in post-MW (post-MW Δ6 ± 2 vs pre-MW Δ11 ± 2 mm Hg, P < 0.05). Aortic PP (post-MW Δ8 ± 2 vs pre-MW Δ3 ± 2), Pf (post-MW Δ6 ± 1 vs pre-MW Δ0 ± 1), and Pb (post-MW Δ5 ± 1 vs pre-MW Δ2 ± 1) augmented during PEMI in post-MW ( P < 0.05 for all), but not in pre-MW. Reflection magnitude increased during PEMI only in pre-MW (pre-MW Δ7 ± 2 vs post-MW Δ-1 ± 2, P < 0.05) due to concurrent increases in Pf and Pb in post-MW. CONCLUSIONS: Even in nonhypertensive postmenopausal women, increases in Pf and Pb and decrease in aortic DBP are important factors that contribute to the augmented aortic PP response to PEMI.


Asunto(s)
Presión Arterial , Análisis de la Onda del Pulso , Adulto Joven , Humanos , Femenino , Presión Arterial/fisiología , Fuerza de la Mano , Plomo , Presión Sanguínea/fisiología , Menopausia , Músculo Esquelético/fisiología
16.
Nutrients ; 15(1)2022 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-36615732

RESUMEN

Hypertension is highly prevalent in postmenopausal women. Endothelial dysfunction is associated with hypertension and the age-related decreases in muscle mass and strength. L-citrulline supplementation (CIT) and slow velocity low-intensity resistance training (SVLIRT) have improved vascular function, but their effect on muscle mass is unclear. We investigated whether combined CIT and SVLIRT (CIT + SVLIRT) would have additional benefits on leg endothelial function (superficial femoral artery flow-mediated dilation (sfemFMD)), lean mass (LM), and strength in hypertensive postmenopausal women. Participants were randomized to CIT (10 g/day, n = 13) or placebo (PL, n = 11) alone for 4 weeks and CIT + SVLIRT or PL + SVLIRT for another 4 weeks. sfemFMD, leg LM and muscle strength were measured at 0, 4, and 8 weeks. CIT increased sfemFMD after 4 weeks (CIT: Δ1.8 ± 0.3% vs. PL: Δ−0.2 ± 0.5%, p < 0.05) and 8 weeks (CIT + SVLIRT: Δ2.7 ± 0.5% vs. PL + SVLIRT: Δ−0.02 ± 0.5, p = 0.003). Leg LM improved after CIT + SVLIRT compared to PL + SVLIRT (Δ0.49 ± 0.15 kg vs. Δ0.07 ± 0.12 kg, p < 0.05). Leg curl strength increased greater with CIT + SVLIRT compared to PL + SVLIRT (Δ6.9 ± 0.9 kg vs. Δ4.0 ± 1.0 kg, p < 0.05). CIT supplementation alone improved leg endothelial function and when combined with SVLIRT has additive benefits on leg LM and curl strength in hypertensive postmenopausal women.


Asunto(s)
Hipertensión , Entrenamiento de Fuerza , Humanos , Femenino , Citrulina , Posmenopausia/fisiología , Pierna/fisiología , Fuerza Muscular , Músculo Esquelético , Suplementos Dietéticos
17.
Nutrients ; 14(20)2022 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-36297080

RESUMEN

Aging and menopause are associated with decreased nitric oxide bioavailability due to reduced L-arginine (L-ARG) levels contributing to endothelial dysfunction (ED). ED precedes arterial stiffness and hypertension development, a major risk factor for cardiovascular disease. This study investigated the effects of L-citrulline (L-CIT) on endothelial function, aortic stiffness, and resting brachial and aortic blood pressures (BP) in hypertensive postmenopausal women. Twenty-five postmenopausal women were randomized to 4 weeks of L-CIT (10 g) or placebo (PL). Serum L-ARG, brachial artery flow-mediated dilation (FMD), aortic stiffness (carotid-femoral pulse wave velocity, cfPWV), and resting brachial and aortic BP were assessed at 0 and 4 weeks. L-CIT supplementation increased L-ARG levels (Δ13 ± 2 vs. Δ−2 ± 2 µmol/L, p < 0.01) and FMD (Δ1.4 ± 2.0% vs. Δ−0.5 ± 1.7%, p = 0.03) compared to PL. Resting aortic diastolic BP (Δ−2 ± 4 vs. Δ2 ± 5 mmHg, p = 0.01) and mean arterial pressure (Δ−2 ± 4 vs. Δ2 ± 6 mmHg, p = 0.04) were significantly decreased after 4 weeks of L-CIT compared to PL. Although not statistically significant (p = 0.07), cfPWV decreased after L-CIT supplementation by ~0.66 m/s. These findings suggest that L-CIT supplementation improves endothelial function and aortic BP via increased L-ARG availability.


Asunto(s)
Hipertensión , Rigidez Vascular , Humanos , Femenino , Citrulina/farmacología , Presión Sanguínea , Análisis de la Onda del Pulso , Posmenopausia , Óxido Nítrico , Hipertensión/tratamiento farmacológico , Arginina/farmacología , Suplementos Dietéticos
18.
Med Sci Sports Exerc ; 54(5): 761-768, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-34974502

RESUMEN

PURPOSE: Hypertensive postmenopausal women (PMW) have exaggerated exercise systolic blood pressure (SBP) due to impaired functional sympatholysis. l-Citrulline (CIT) supplementation attenuates aortic SBP responses to cold pressor test (CPT)-induced vasoconstriction in young men. We hypothesized that acute CIT ingestion would attenuate aortic SBP and leg hemodynamic responses during exercise and CPT (EX + CPT). METHODS: Fifteen hypertensive PMW (61 ± 7 yr) were randomly assigned to consume either 6 g of CIT or placebo (PL) separated by a minimum 3-d washout phase. Brachial and aortic blood pressure, femoral artery blood flow (FBF), and vascular conductance (FVC) were measured at rest and during 5 min of unilateral plantarflexion exercise with a CPT applied during minutes 4 and 5. RESULTS: No differences between conditions were found in FBF, FVC, and brachial and aortic blood pressure at rest and during exercise alone. Changes in brachial SBP (CIT vs PL, 29 ± 12 vs 40 ± 10 mm Hg) and mean arterial pressure (CIT vs PL, 21 ± 10 vs 33 ± 11 mm Hg), and aortic SBP (CIT vs PL, 27 ± 11 vs 38 ± 9 mm Hg) and mean arterial pressure (CIT vs PL, 23 ± 9 vs 33 ± 11 mm Hg) to EX + CPT were lower in the CIT versus PL condition (P < 0.05). FBF, FVC, and functional sympatholysis (%ΔFVC) were not significantly different between conditions. CONCLUSIONS: Acute CIT ingestion attenuated aortic SBP response to exercise and cold-induced sympathetic activation that may prevent left ventricle overload in hypertensive PMW.


Asunto(s)
Citrulina , Hipertensión , Anciano , Presión Arterial , Presión Sanguínea/fisiología , Citrulina/farmacología , Suplementos Dietéticos , Femenino , Humanos , Hipertensión/prevención & control , Masculino , Persona de Mediana Edad , Posmenopausia
19.
Exp Gerontol ; 159: 111685, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34990772

RESUMEN

BACKGROUND AND AIMS: Augmented aortic systolic blood pressure (SBP) and wave reflection via sympathetic-mediated vasoconstriction elevates the risk for adverse cardiovascular events in older adults. L-citrulline (L-CIT) supplementation has shown to reduce aortic SBP and pulse pressure (PP) responses to cold pressor test (CPT) induced sympathoactivation in young men. The aim of this study was to elucidate the efficacy of L-CIT supplementation to attenuate aortic hemodynamic responses to CPT in older adults. METHODS AND RESULTS: Sixteen older adults were randomly assigned to placebo or L-CIT (6 g/day) for 14-days in a crossover, double-blind, placebo-controlled design. Brachial SBP and aortic SBP, PP, augmented pressure (AP), augmentation index standardized at 75 bpm (AIx@75), and pressure of the forward (Pf) and reflected (Pb) waves were evaluated at rest and during CPT pre- and post-intervention. Although no hemodynamic changes at rest, brachial SBP (Δ-12 ± 18 vs. Δ4 ± 14 mmHg; P = 0.008) and aortic SBP (Δ-10 ± 14 vs. Δ4 ± 12 mmHg; P = 0.005), PP (Δ-10 ± 12 vs. Δ4 ± 11 mmHg; P = 0.002), AP (Δ-4 ± 4 vs. Δ2 ± 7 mmHg; P = 0.004), AIx@75 (Δ-3.2 ± 7.2 vs. Δ2.2 ± 6.9%; P = 0.038), Pf (Δ-6 ± 10 vs. Δ3 ± 9 mmHg; P = 0.019), and Pb (Δ-4 ± 6 vs. Δ2 ± 6 mmHg; P = 0.008) responses to the CPT were significantly attenuated following L-CIT supplementation vs. placebo. CONCLUSIONS: L-CIT supplementation attenuated aortic pulsatile pressure and pressure wave reflection responses to CPT in older adults, providing possible cardioprotection during cold-induced sympathoactivation in older adults.


Asunto(s)
Citrulina , Rigidez Vascular , Anciano , Presión Arterial/fisiología , Presión Sanguínea , Citrulina/farmacología , Respuesta al Choque por Frío , Suplementos Dietéticos , Humanos , Masculino , Análisis de la Onda del Pulso/métodos
20.
Mayo Clin Proc Innov Qual Outcomes ; 6(1): 45-54, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35005437

RESUMEN

OBJECTIVE: To design and evaluate, through a human-centered design approach, a multispeciality clinic for patients with central sensitization syndromes that combined virtual previsit consultations, traditional face-to-face appointments, and technology-enabled educational programming. PATIENTS AND METHODS: Patients with suspected fibromyalgia and chronic abdominal pain were seen in a multispecialty practice, and the performance of the clinic was evaluated against a contemporary cohort. Quantitative and qualitative evaluation measures included team estimates of time spent on care-related tasks, physician rank of alignment of patient need with clinic design, major appointment changes, and nonvisit care tasks. Members of the care team also evaluated strengths, weaknesses, opportunities, and threats to the success of the clinic. RESULTS: The pilot clinic was operated from April 1, 2020, to April 30, 2021, and included 34 patients with suspected fibromyalgia/chronic abdominal pain. During the pilot period, physicians ranked the value of the virtual previsit consultations in providing care as 7.5 on a scale of 0 to 10 and reported an average of 50 minutes in preparation for the appointment, execution of the appointment, and postvisit documentation. We did not observe substantial differences in the number of added appointments or messages received within the patient portal when compared with a comparison cohort. Patients who participated in the combination nurse educator-led and digital education program provided positive feedback about their experience. CONCLUSION: Our clinic model provides a framework for the treatment of patients with debilitating centrally sensitized conditions and future expansion of virtual care delivery models to better meet patient care and educational needs.

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