The objective of this study was to investigate the effects of losartan (100 mg) plus hydrochlorothiazide (HCTZ; 25 mg) on nitric oxide (NO) production and blood pressure (BP) in "nondipper" severe ...hypertensive patients. Twelve hypertensive "nondipper patients" (6 of each gender) with sitting systolic/diastolic BP of 188.0 +/- 5.2/116.2 +/- 1.2 mm Hg were studied by 24-hour ambulatory blood pressure monitoring (ABPM) after daily administration of 100 mg losartan plus 25 mg HCTZ for a period of 12 weeks. Office and mean 24-hour, as well as mean awake- and sleep-time systolic/diastolic BP, serum NO levels, and urinary excretion of NO were measured after the placebo period (3 weeks) and after 12 weeks of therapy. At the end of the 12-week treatment period, the mean 24-hour systolic/diastolic BP decreased significantly from 158.6 +/- 4.7/102.2 +/- 2.6 mm Hg (placebo period) to 140.3 +/- 4.8/90.9 +/- 3.3 mm Hg (P = 0.001/< or = 0.002). The mean BP (systolic/diastolic) during the waking period was reduced from 159.3 +/- 4.4/103.0 +/- 2.5 mm Hg to 135.0 +/- 4.4/88.2 +/- 3.1 (P < or = 0.007/P < or = 0.002), whereas the mean BP (systolic/diastolic) during the sleeping hours changed from 154.9 +/- 5.3/98.9 +/- 3.1 to 140.9 +/- 4.6 (P = 0.035)/91.7 +/- 3.2 mm Hg (P = 0.035/P = 0.051). Serum NO levels increased from 40.89 +/- 5.69 microM/L (placebo period) to 67.35 +/- 6.96 microM/L (posttreatment; P < or = 0.007), whereas the 24-hour urinary NO excretion did not change significantly (69.71 +/- 3.68 microM/L placebo period vs 79.64 +/- 4.25 microM/L posttreatment; P < or = 0.16). Urinary clearance of NO also did not change. Serum NO levels increased significantly without a significant change in urinary NO excretion. BP was significantly reduced but without modifying the nondipper pattern in these patients.
The aim of this study was to evaluate the fibrinolytic system by measurement of fibrinogen, plasminogen, tissue-type plasminogen activator (t-PA), and plasminogen activator inhibitor-1 (PAI-1) in ...healthy normotensive subjects and in patients with essential hypertension. A group of 21 healthy normotensive subjects age, 39.2 +/- 1.8 years; 8 males, 13 females; body mass index (BMI) = 27.9 kg/m and 42 patients with untreated essential hypertension (age, 47.6 +/- 1.7 years; 19 males, 23 females; BMI = 28.3 kg/m) were studied. Blood samples and clinical measurement were taken between 7 am and 9 am by an observer in a blind fashion. The systolic/diastolic blood pressure of normotensive subjects was 121.3 +/- 2.5/78.4 +/- 1.3 mm Hg and that of hypertensive patients was 166.4 +/- 4.3/102.9 +/- 1.83 mm Hg, measured in the sitting position. Plasma fibrinogen levels in the normotensive and hypertensive individuals were 295.7 +/- 9.4 mg/dL and 305.67 +/- 10.9 mg/dL, respectively (P = 0.456). The corresponding values for plasminogen were 71.4 +/- 3.8% and 89.5 +/- 2.5%, (P = 0.0031), for t-PA were 6.3 +/- 0.5 ng/mL and 7.6 +/- 0.4 ng/mL (P = 0.0487), and for PAI-1 were 46.9 +/- 5.1 ng/mL and 63.0 +/- 5.6 ng/mL (P = 0.0324), respectively. In conclusion, patients with essential hypertension have disequilibrium in the fibrinolytic system with a tendency toward a hypercoagulability state when compared with normotensive subjects. This state could explain, in part, the thrombotic complications that occur with a higher frequency in hypertensive patients as compared with normotensive subjects.
This review summarizes the prevalence of hypertension and the state of cardiovascular health in Venezuela and surrounding nations. First, the review discusses the fact that cardiovascular disease ...(CVD) is the main cause of death in Venezuela, Colombia, Brazil, and Trinidad and Tobago, accounting for 20% to 35% of all deaths. These data are similar to data from the developed world. Second, prevalence of hypertension in this region varies from 8% to 40% in the adult population, and, on average, 22% of the adult population of this region has an elevated blood pressure. However, prevalence rates vary considerably from country to country and within regions of the same country. Although mortality from hypertension as the main cause of death accounts for 1% to 4% of all deaths, mortality from stroke, mainly caused by hypertension, accounts for 10% of all deaths, indicating a failure in the treatment of hypertension. In most Latin American countries, the degree of awareness, treatment and control of hypertension is low, necessitating the establishment of programs to prevent, detect and effectively treat hypertension and decrease CVD risk factors.
Antihypertensive effect, platelet aggregation, and plasma lipid profile were studied in a group of 14 hypertensive patients with diastolic blood pressure between 96 and 116 mm Hg during placebo and ...terazosin phases. Terazosin, an
α
1-adrenergic blocking agent, was given initially at the dosage of 1 mg daily. Then it was continued at a dosage of 2 mg daily and 5 mg daily respectively, each dosage for 4 weeks. Blood pressure was taken every 2 weeks. Ex vivo platelet aggregation induced by epinephrine, collagen, and adenosine diphosphate (ADP) were carried out twice during the first placebo phase, once at the end of each terazosin dosage, and once in the second placebo phase. Total cholesterol, HDL cholesterol, and triglycerides were measured at the end of first placebo and terazosin phases. Blood from eight patients was taken during the second placebo phase to carry out in vitro response of platelet aggregation induced by ADP, collagen, and epinephrine before and after incubation with terazosin (1, 2 and 5 μg/L or doxazosin (100, 200, and 500 μg/L) for 5 min.
Terazosin induced a statistically significant decrease in
14.2
8.0
mm Hg,
26.1
13.4
mm Hg, and
33.9
16.5
mm Hg in the supine position for 1, 2, and 5 mg/daily, respectively. No changes in heart rate were observed. Terazosin inhibited significant ex vivo platelet aggregation induced by epinephrine, collagen, and ADP in a range from 20% to 45% for different concentrations of inducers. Reductions in platelet aggregation seemed not to be dose dependent, as reductions were statistically equivalent for dosages of 1, 2, and 5 mg daily. Terazosin significantly reduced the level of total cholesterol (8.71%) and triglycerides (14.31%), and increased (although not significantly) levels of HDL cholesterol (3.91%). In vitro platelet aggregation was inhibited by doxazosin to a significant extent but not by terazosin.
It is well established that patients with systemic sclerosis (SSc) have a disrupted lipid profile and an increased cardiovascular risk. Cholesterol efflux capacity (CEC), the ability of high-density ...lipoprotein (HDL)-cholesterol to accept cholesterol from macrophages, has been linked to cardiovascular events. The aim of this study was to establish whether CEC and lipid profile were impaired in SSc patients with respect to controls and whether these changes were associated with disease-related data.
Cross-sectional study encompassed 188 individuals: 73 SSc patients and 115 controls. CEC, using an in vitro assay, and lipoprotein serum concentrations were assessed in patients and controls. A multivariable analysis was performed to study the differences in CEC between patients and controls, and if SSc-related data could explain such differences.
The multivariable analysis adjusted for demographic characteristics, cardiovascular risk factors, and lipid-related molecules showed that total cholesterol (beta coefficient: - 22 95%CI - 37 to - 7, p = 0.004), triglycerides (beta coefficient: 24 95%CI 2-47, p = 0.033), lipoprotein A (beta coefficient: 22 95%CI 2-43, p = 0.033), and CEC (beta coefficient: - 6 95%CI - 10 to - 2%,p = 0.002) were significantly different between patients and controls. Skin thickness, as assessed by modified Rodnan skin score, was independently associated with a lower CEC (beta coefficient: - 0.21 95%CI - 0.37 to - 0.05%, p = 0.011) after multivariable adjustment.
SSc patients show an abnormal lipid profile with respect to controls including CEC. Skin thickness is independent and inversely associated with CEC in SSc patients.
Background and purpose
The aim was to systematically review the effectiveness and safety of telemedicine combined with usual care (in‐person visits) compared to usual care for the therapeutic ...management and follow‐up assessment of neurological diseases.
Methods
The electronic databases MEDLINE, Embase, Web of Science and Cochrane Central Register of Controlled Trials were searched (June 2021). Randomized controlled trials (RCTs) on patients of any age with neurological diseases were considered. Two reviewers screened and ed data in duplicate and independently and assessed risk of bias using the Cochrane risk‐of‐bias tool for randomized trials (RoB 2). When possible, pooled effect estimates were calculated.
Results
Of a total of 3018 records initially retrieved, 25 RCTs (n = 2335) were included: 11 (n = 804) on stroke, four (n = 520) on Parkinson's disease, three (n = 110) on multiple sclerosis, two (n = 320) on epilepsy, one (n = 63) on dementia, one (n = 23) on spina bifida, one (n = 40) on migraine, one (n = 22) on cerebral palsy and one (n = 433) on brain damage. Types of telemedicine assessed were online visits (11 studies), tele‐rehabilitation (seven studies), telephone calls (three), smartphone apps (two) and online computer software (two). The evidence was quite limited except for stroke. Compared to usual care alone, telemedicine plus usual care was found to improve depressive symptoms, functional status, motor function, executive function, generic quality of life, healthcare utilization and healthy lifestyle in patients in post‐stroke follow‐up.
Conclusions
Well‐designed and executed RCTs are needed to confirm our findings on stroke and to have more scientific evidence available for the other neurological diseases.
This article presents an improved nonlinear empirical I/V model suitable for GaAs and GaN FETs. The new drain‐to‐source current formulation accurately represents the symmetric and the asymmetric ...bell‐shaped transconductance (gm) for all VDS values. Besides modeling with high accuracy the I/V characteristic, the proposed model can fit the first and second derivatives of the transconductance, from the ohmic to the saturation region, including the pinch‐off region. The high correlation between experimental and simulated data of the I/V curves of GaAs and GaN FETs, ACPR, load‐pull, and a class‐J power amplifier designed in S‐band corroborates the usefulness of the proposed model, considering only the static I/V model as the main nonlinear element of the electrical equivalent circuit model of the transistor.
Spin crossover (SCO) molecules are promising nanoscale magnetic switches due to their ability to modify their spin state under several stimuli. However, SCO systems face several bottlenecks when ...downscaling into nanoscale spintronic devices: their instability at the nanoscale, their insulating character and the lack of control when positioning nanocrystals in nanodevices. Here we show the encapsulation of robust Fe-based SCO molecules within the 1D cavities of single-walled carbon nanotubes (SWCNT). We find that the SCO mechanism endures encapsulation and positioning of individual heterostructures in nanoscale transistors. The SCO switch in the guest molecules triggers a large conductance bistability through the host SWCNT. Moreover, the SCO transition shifts to higher temperatures and displays hysteresis cycles, and thus memory effect, not present in crystalline samples. Our results demonstrate how encapsulation in SWCNTs provides the backbone for the readout and positioning of SCO molecules into nanodevices, and can also help to tune their magnetic properties at the nanoscale.
Liquid crystals are known to be particularly sensitive to orientational cues provided at surfaces or interfaces. In this work, we explore theoretically, computationally, and experimentally the ...behavior of liquid crystals on isolated nanoscale patterns with controlled anchoring characteristics at small length scales. The orientation of the liquid crystal is controlled through the use of chemically patterned polymer brushes that are tethered to a surface. This system can be engineered with remarkable precision, and the central question addressed here is whether a characteristic length scale exists at which information encoded on a surface is no longer registered by a liquid crystal. To do so, we adopt a tensorial description of the free energy of the hybrid liquid-crystal–surface system, and we investigate its morphology in a systematic manner. For long and narrow surface stripes, it is found that the liquid crystal follows the instructions provided by the pattern down to 100 nm widths. This is accomplished through the creation of line defects that travel along the sides of the stripes. We show that a “sharp” morphological transition occurs from a uniform undistorted alignment to a dual uniform/splay-bend morphology. The theoretical and numerical predictions advanced here are confirmed by experimental observations. Our combined analysis suggests that nanoscale patterns can be used to manipulate the orientation of liquid crystals at a fraction of the energetic cost that is involved in traditional liquid crystal-based devices. The insights presented in this work have the potential to provide a new fabrication platform to assemble low power bistable devices, which could be reconfigured upon application of small external fields.
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