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1.
Langmuir ; 40(1): 1117-1129, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38115197

RESUMEN

This study demonstrated the importance of identifying the optimal balance of hydrophilic and hydrophobic moieties in amphiphilic coatings to achieve fouling-release (FR) performance that surpasses that of traditional hydrophobic marine coatings. While there have been many reports on fouling-release properties of amphiphilic surfaces, the offered understanding is often limited. Hence, this work is focused on further understanding of the amphiphilic surfaces. Poly(ethylene glycol) (PEG) and polydimethylsiloxane (PDMS) were used to create a series of noncross-linked amphiphilic additives that were then added to a hydrophobic-designed siloxane-polyurethane (SiPU) FR system. After being characterized by ATR-FTIR, XPS, contact angle analysis, and AFM, the FR performance was evaluated by using different marine organisms. The assessments showed that the closer the hydrophilic and hydrophobic moieties in a system reached a relatively equalized level, the more desirable the FR performance of the coating system became. A balanced ratio of hydrophilicity-hydrophobicity in the system at around 10-15 wt % of each component had the best FR performance and was comparable to or better than commercial FR coatings.

2.
Drug Chem Toxicol ; : 1-9, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-37017136

RESUMEN

Coffee is the most popular beverage after water in the world, which has an important role in health as a result of various minerals and vitamins but it may be pollution source of potentially toxic elements (PTEs) that can threate the health. Thus, the current study intended to detect the level of PTEs such as Cadmium (Cd), Copper (Cu), Lead (Pb), Nickel (Ni), Znc (Zn) and Iron (Fe), in various coffee and coffee-based products (powder, ground, processed, infusion and bean). Considering the databases of Scopus, Google scholar, PubMed, and Web of Science, the concentration of PTEs in coffee and coffee-based products was retrieved and meta-analyzed. Additionally, the non-carcinogenic risks in terms of total hazard quotient (TTHQ) were assessed using Monte Carlo simulated (MCS) model. According to the findings of 23 articles, the ranking of metal concentration in different coffees was Fe > Zn > Cu> Ni > Pb > Cd in powder, Fe > Cu > Zn> Ni in ground, Fe > Zn > Ni> Cu> Pb > Cd in processed and infusion and Fe > Zn > Ni> Cs > Pb in bean. Moreover, based on WHO regions, the highest concentrations of Cd and Pb (0.742 mg/kg) were related to the South-East Asia Region (SEARO) and European region (EURO) respectively. However, the highest concentrations of Fe (81.161 mg/kg), Zn (33.392 mg/kg), Cu (9.408 mg/kg), and Ni (18.064 mg/kg) were related to Pan American health organization (PAHO), PAHO, PAHO and Eastern Mediterranean Region (EMRO), respectively. On the other hand, the risk pattern was different in different countries. Moreover, consumers in some countries were not at significant non-carcinogenic risks because of ingestion of PTEs via coffee and consumption of coffee-based products.

3.
Health Info Libr J ; 40(1): 3-28, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36637218

RESUMEN

BACKGROUND: Patient education information material (PEIM) is an essential component of patient education programs in increasing patients' ability to cope with their diseases. Therefore, it is essential to consider the criteria that will be used to prepare and evaluate these resources. OBJECTIVE: This paper aims to identify these criteria and recognize the tools or methods used to evaluate them. METHODS: National and international databases and indexing banks, including PubMed, Scopus, Web of Science, ProQuest, the Cochrane Library, Magiran, SID and ISC, were searched for this review. Original or review articles, theses, short surveys, and conference papers published between January 1990 and June 2022 were included. RESULTS: Overall, 4688 documents were retrieved, of which 298 documents met the inclusion criteria. The criteria were grouped into 24 overarching criteria. The most frequently used criteria were readability, quality, suitability, comprehensibility and understandability. CONCLUSION: This review has provided empirical evidence to identify criteria, tools, techniques or methods for developing or evaluating a PEIM. The authors suggest that developing a comprehensive tool based on these findings is critical for evaluating the overall efficiency of PEIM using effective criteria.


Asunto(s)
Educación del Paciente como Asunto , Humanos
4.
Appl Soft Comput ; 144: 110511, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37346824

RESUMEN

The outbreak of the corona virus disease (COVID-19) has changed the lives of most people on Earth. Given the high prevalence of this disease, its correct diagnosis in order to quarantine patients is of the utmost importance in the steps of fighting this pandemic. Among the various modalities used for diagnosis, medical imaging, especially computed tomography (CT) imaging, has been the focus of many previous studies due to its accuracy and availability. In addition, automation of diagnostic methods can be of great help to physicians. In this paper, a method based on pre-trained deep neural networks is presented, which, by taking advantage of a cyclic generative adversarial net (CycleGAN) model for data augmentation, has reached state-of-the-art performance for the task at hand, i.e., 99.60% accuracy. Also, in order to evaluate the method, a dataset containing 3163 images from 189 patients has been collected and labeled by physicians. Unlike prior datasets, normal data have been collected from people suspected of having COVID-19 disease and not from data from other diseases, and this database is made available publicly. Moreover, the method's reliability is further evaluated by calibration metrics, and its decision is interpreted by Grad-CAM also to find suspicious regions as another output of the method and make its decisions trustworthy and explainable.

5.
Int Ophthalmol ; 42(7): 2273-2288, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35041131

RESUMEN

PURPOSE: To systematically review the published manuscripts on stereopsis after corneal refractive surgery. METHODS: The Web of Science, PubMed, Scopus, ProQuest, Clinical Key, Embase, and Cochrane Library were searched for relevant articles published until August 2020. The fixed- or random-effects models were used to estimate the Weighted mean difference (WMD) or Relative risk (RR) and 95% Confidence interval (CI) for postoperative stereopsis changes and incidence when applicable. Meta-regression was conducted for adjusting the effects of potential confounders. RESULTS: Seven studies (1266 eyes) in adults and ten studies in pediatrics (259 eyes) were included. In adults, stereopsis improved significantly compared to the preoperative state (WMD = - 27.4, 95% CI = - 40.0, - 14.7; I2 = 97.8%; P < 0.001). In pediatrics, proportion of patients with stereoacuity postoperatively was 2.18 times compared to preoperative evaluation. (RR = 2.18, 95% CI = 1.2, 3.9; I2 = 68.6%, P < 0.001). CONCLUSIONS: Stereopsis improves after corneal refractive surgery in adults and pediatrics.


Asunto(s)
Procedimientos Quirúrgicos Refractivos , Adulto , Niño , Percepción de Profundidad , Humanos , Agudeza Visual
6.
J Res Med Sci ; 27: 74, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36353345

RESUMEN

Background: Paraquat (PQ) poisoning is a serious public health concern, especially in developing countries, due to its easy access and lack of awareness of potential harms. No effective treatment has been reported yet. Conventional hemodialysis (HD) is still used in many centers for excreting PQ or reducing acute kidney injury, but there is no consensus on its efficacy. Therefore, we aimed to review the HD efficacy in PQ poisoning mortality. Materials and Methods: We searched Web of Science, PubMed, Excerpta Medical Database, Google Scholar, Scopus, Cochrane, Web of Knowledge, Pro-Quest, ScienceDirect, Springer, Clinical Key, Scientific Information Database, Magiran, and Iran-doc, in publications before January 1, 2020. We compared patients who underwent HD (Group 1) with those who did not (Group 2). The outcome was considered mortality/survival. The data were analyzed by Comprehensive Meta-analysis Software. Results: This systematic review and meta-analysis included five studies with a combined total of 203 patients. The patients in the Group 1 had higher mortality than Group 2 (odds ratio, 2.84; 95% confidence interval: 1.22-6.64; P = 0.02). There was no evidence of publication bias (P value for Egger's test = 0.833). Conclusion: Although HD did not affect the survival of patients, other variables such as the amount of ingested PQ, poisoning severity, the time between PQ ingestion and the start of HD, duration, and times of HD sessions may influence the results regarding mortality.

7.
Langmuir ; 37(8): 2728-2739, 2021 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-33586437

RESUMEN

Amphiphilic surfaces, containing both hydrophilic and hydrophobic domains, offer desirable performance for many applications such as marine coatings or anti-icing purposes. This work explores the effect of the concentration of amphiphilic moieties on converting a polyurethane (PU) system to a coating having fouling-release properties. A novel amphiphilic compound is synthesized and added at increasing amounts to a PU system, where the amount of the additive is the only variable in the study. The additive-modified surfaces are characterized by a variety of techniques including ATR-FTIR, XPS, contact angle measurements, and AFM. Surface characterizations indicate the presence of amphiphilic domains on the surface due to the introduction of the self-stratifying amphiphilic additive. The fouling-release properties of the surfaces are assessed with three biological assays using Ulva linza, Cellulophaga lytica, and Navicula Incerta as the test organisms. A change in the fouling-release performance is observed and plateaued once a certain amount of amphiphilicity is attained in the coating system, which we call the critical amphiphilic concentration (CAC).


Asunto(s)
Incrustaciones Biológicas , Flavobacteriaceae , Ulva , Incrustaciones Biológicas/prevención & control , Propiedades de Superficie
8.
J Med Libr Assoc ; 109(1): 33-43, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33424462

RESUMEN

OBJECTIVES: Access to high-quality information improves the quality of patient care, but lack of time and sufficient skills in information seeking can prevent access to information by clinicians. To solve this problem, clinical informationists can provide high-quality, filtered information for clinical team members. This study identified the core competencies that clinical informationists need to effectively fulfill their roles on clinical teams. METHODS: Participants were selected purposefully from clinicians and medical librarians. Data were collected through semi-structured interviews and analyzed using qualitative content analysis. RESULTS: The authors identified six competencies-communication, research, education and training, domain knowledge, information services, and technology-which together were used to develop a "CREDIT" model of core competencies for clinical informationists. CONCLUSIONS: The CREDIT model can be used as criteria for evaluating the performance of clinical informationists as well as for developing and assessing clinical informationist educational programs and curriculums.


Asunto(s)
Almacenamiento y Recuperación de la Información/métodos , Bibliotecólogos/estadística & datos numéricos , Bibliotecas Médicas/organización & administración , Competencia Profesional/normas , Rol Profesional , Humanos , Relaciones Interprofesionales
9.
Nature ; 515(7526): 249-52, 2014 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-25363781

RESUMEN

Lignin is a heterogeneous aromatic biopolymer that accounts for nearly 30% of the organic carbon on Earth and is one of the few renewable sources of aromatic chemicals. As the most recalcitrant of the three components of lignocellulosic biomass (cellulose, hemicellulose and lignin), lignin has been treated as a waste product in the pulp and paper industry, where it is burned to supply energy and recover pulping chemicals in the operation of paper mills. Extraction of higher value from lignin is increasingly recognized as being crucial to the economic viability of integrated biorefineries. Depolymerization is an important starting point for many lignin valorization strategies, because it could generate valuable aromatic chemicals and/or provide a source of low-molecular-mass feedstocks suitable for downstream processing. Commercial precedents show that certain types of lignin (lignosulphonates) may be converted into vanillin and other marketable products, but new technologies are needed to enhance the lignin value chain. The complex, irregular structure of lignin complicates chemical conversion efforts, and known depolymerization methods typically afford ill-defined products in low yields (that is, less than 10-20wt%). Here we describe a method for the depolymerization of oxidized lignin under mild conditions in aqueous formic acid that results in more than 60wt% yield of low-molecular-mass aromatics. We present the discovery of this facile C-O cleavage method, its application to aspen lignin depolymerization, and mechanistic insights into the reaction. The broader implications of these results for lignin conversion and biomass refining are also considered.


Asunto(s)
Formiatos/química , Lignina/química , Polimerizacion , Biomasa , Estructura Molecular
10.
Health Info Libr J ; 37(2): 143-151, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31592573

RESUMEN

BACKGROUND: Clinical specialists require access to the most recent and up to date professional information. However, barriers such as insufficient time and lack of necessary information retrieval skills necessitate the presence of clinical informationist (CI) in medical teams. OBJECTIVES: This study sought to determine the pre-requisite for CI participation in the grand round. METHODS: This was a qualitative study carried out using content analysis approach. Study involved all fellowship students and attending physicians in the department of gastroenterology at Al-Zahra hospital in Isfahan (Iran), who were selected using purposive sampling. Gathered reports were analysed using qualitative content analysis and concept mapping approaches. DISCUSSION: To improve the process of CI collaboration with clinical specialists during the educational rounds, it is necessary for CI to have certain pre-requisite skills. CONCLUSIONS: By identifying the pre-requisites for CI participation in the grand round and explaining advantages of this participation for clinical specialists, this study proposes a suitable process for implantation of CI participation in grand rounds.


Asunto(s)
Servicios de Información/tendencias , Rol Profesional/psicología , Rondas de Enseñanza/métodos , Humanos , Irán , Investigación Cualitativa
11.
J Res Med Sci ; 24: 2, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30815015

RESUMEN

BACKGROUND: Paraquat (PQ) poisoning is a serious public health problem in many countries. In spite of different treatments, the mortality is still high. We performed a meta-analysis to see whether hemoperfusion (HP) in combination with other treatments reduces the mortality more than HP alone in patients with PQ poisoning. MATERIALS AND METHODS: We searched EMBASE, PubMed, Google Scholar, ISI Web of Knowledge, Cochrane Central Register of Controlled Trials, Scopus, Springer, TRIP, ProQuest, and references of the included studies from January 2000 to August 2017. Two reviewers independently searched and extracted data. We measured I 2 to determine variance contributed by heterogeneity. To investigate the publication bias, Begg's and Egger's tests were used along with funnel plot analysis. RESULTS: Ultimately 12 articles were included in the meta-analysis. Five articles compared HP with conventional therapy with a total of 1311 patients, and seven articles compared mortality of patients received HP versus those received HP in combination with an additional treatment. HP alone reduced the odds of death (odds ratio [OR] = 0.20; 95% confidence interval [CI]: 0.11-0.40, P < 0.0001) compared to conventional therapy. Furthermore, the odds of death was higher in HP group compared to those received HP in combination of additional treatments (OR = 1.24; 95% CI: 1.05-1.46, P = 0.01). CONCLUSION: The mortality was less in HP-treated group compared to those received only conventional therapy. Addition of other treatments with HP reduced the mortality more than HP alone.

12.
Health Info Libr J ; 35(3): 180-191, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30160384

RESUMEN

OBJECTIVE: The purpose of this study was to examine the models and methods for evaluating digital libraries. METHODS: Springer, Science Direct, ProQuest, Emerald, Wiley, LISTA, Web of Science (WOS), Scopus, Magiran (Persian), Irandoc (Persian), SID (Persian) and Noormags (Persian) databases were searched systematically based on the defined criteria. Selection criteria included full-text articles and dissertations published in English and Persian languages in 2004-2017. The final included articles (n = 64) were reviewed, selected and analysed by group discussions. RESULTS: The results of analysing 64 included articles for this systematised review specified that the evaluation of digital libraries is mostly focused on the service quality aspect, and DigiQual was the most frequently used model. Few studies have evaluated digital libraries in the health sector. The researcher developed questionnaire is the most frequently used method to evaluate digital libraries. CONCLUSION: Because there are fewer studies of digital libraries evaluation in the health sector, the specific features of health digital libraries should be addressed by librarians and health digital library designers to develop specific models.


Asunto(s)
Gestión de la Información en Salud/métodos , Bibliotecas Digitales/tendencias , Bibliotecas Médicas , Humanos , Bibliotecas Digitales/normas
13.
Nutr Cancer ; 69(6): 840-848, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28742387

RESUMEN

The dangerous dose-dependent side effects of anticancer agents triggered the finding of new approaches for elevated chemotherapy efficacy. This study investigated the potential application of nanostructured lipid careers (NLCs) in increasing vitamin D3 (VitD) effectiveness in breast cancer cell (MCF-7) in concurrent administration with doxorubicin (Dox). VitD-loaded NLCs were characterized by particle size, zeta potential, Fourier transform infrared spectroscopy, and scanning electron microscope. Cytotoxicity and molecular effects of formulation were evaluated by MTT, DAPI staining, flow cytometry, and real-time quantitative PCR assays. The formulation revealed mean particle size of 87±5 nm with a polydispersity index of 0.24 confirmed by SEM images. The IC50 values for VitD and Dox were 1.3 ± 0.04 and 0.65 ± 0.05 µM, respectively. VitD-loaded NLCs decreased the percentage of cell proliferation from 49 ± 7.2% to 37 ± 5.1% (P < 0.05). Cotreatment of the cells with VitD-loaded NLCs and Dox caused over a twofold increase in the percentage of apoptosis (P < 0.05). Gene expression profile demonstrated a significant decrease in antiapoptotic factor survivin along with increase in proapoptotic factor Bax mRNA levels. Overall, our results introduced the NLC technology as a novel strategy to elevate the efficacy of chemotherapeutics in breast cancer.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Doxorrubicina/farmacología , Portadores de Fármacos/química , Nanoestructuras/química , Vitamina D/química , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Doxorrubicina/administración & dosificación , Femenino , Regulación de la Expresión Génica , Humanos , Proteínas Inhibidoras de la Apoptosis/genética , Proteínas Inhibidoras de la Apoptosis/metabolismo , Concentración 50 Inhibidora , Células MCF-7 , Tamaño de la Partícula , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Survivin , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismo
15.
J Cataract Refract Surg ; 50(7): 767-776, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38353281

RESUMEN

Laser vision correction for residual refractive errors in patients with previous radial keratotomy (RK) presents a challenging task. Different techniques have been used with varying outcomes. This study aimed to systematically review published articles on refractive surgeries in post-RK patients by conducting a search on PubMed, Scopus, and Web of Science. The final analysis included 35 studies that described a total of 888 eyes. Our systematic review and meta-analysis demonstrated a significant improvement in uncorrected distance visual acuity (UDVA) for photorefractive keratectomy (PRK), topography-guided PRK, wavefront-guided PRK, and femtosecond laser-assisted in situ keratomileusis (LASIK) while mechanical microkeratome LASIK did not yield such significant improvements. Moreover, our results suggest that post-RK patients with hyperopia had a significant improvement in UDVA, whereas no such improvement was observed in patients with myopia.


Asunto(s)
Queratomileusis por Láser In Situ , Queratotomía Radial , Refracción Ocular , Agudeza Visual , Humanos , Agudeza Visual/fisiología , Refracción Ocular/fisiología , Queratomileusis por Láser In Situ/métodos , Queratectomía Fotorrefractiva/métodos , Láseres de Excímeros/uso terapéutico , Errores de Refracción/fisiopatología , Miopía/cirugía , Miopía/fisiopatología , Hiperopía/cirugía , Hiperopía/fisiopatología
16.
J Geriatr Phys Ther ; 47(2): 85-96, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-36827693

RESUMEN

BACKGROUND AND PURPOSE: Thoracic hyperkyphosis may adversely influence physical function in older adults, but the literature is mixed and confounded by possible sex differences. This systematic review and meta-analysis aimed to examine the association between hyperkyphosis and physical function in older females. METHODS: Scopus, ISI Web of Science, Cochrane Library, PubMed, CINAHL, and PEDro databases were searched through 2021 for studies that included measures of thoracic hyperkyphosis and physical function with extractable data for women older than 60 years. Studies were excluded if they were qualitative, case reports, case series, ecological studies, reviews, or were not published in English. The study quality and risk of bias were assessed using checklists from the National Heart, Lung, and Blood Institute. Data were synthesized using Cohen's d effect size and 95% confidence interval (CI), and random-effects models were used for the meta-analyses. RESULTS AND DISCUSSION: Three cohort and 22 cross-sectional studies of fair to good quality met the inclusion criteria. Eight studies reporting single-group data showed a moderate association between greater kyphosis angles and lower physical function ( d = -0.57; 95% CI -0.73, -0.40). Fourteen studies reporting 2-group data showed a large negative effect on physical function for groups with greater kyphosis angles ( d = -1.16; 95% CI -1.53, -0.78). Three studies that reported multivariate data also tended to show negative associations between physical function and hyperkyphosis. Limitations include a relative lack of causal evidence; confirming causation requires additional longitudinal studies. Studies have assessed various physical function categories, including strength, gait, and balance. Future studies could determine the categories of function most affected so that preventive interventions could target hyperkyphosis appropriately. CONCLUSIONS: Hyperkyphosis was associated with lower physical function in older women. Three cohort studies suggest that greater kyphosis angles may predict greater loss of physical function over time. These results imply that therapies that help to minimize hyperkyphosis may help preserve function in older women.


Asunto(s)
Cifosis , Humanos , Femenino , Masculino , Anciano , Estudios Transversales , Estudios de Cohortes
17.
J Med Chem ; 67(4): 2369-2378, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38335279

RESUMEN

There remains a need to develop novel SARS-CoV-2 therapeutic options that improve upon existing therapies by an increased robustness of response, fewer safety liabilities, and global-ready accessibility. Functionally critical viral main protease (Mpro, 3CLpro) of SARS-CoV-2 is an attractive target due to its homology within the coronaviral family, and lack thereof toward human proteases. In this disclosure, we outline the advent of a novel SARS-CoV-2 3CLpro inhibitor, CMX990, bearing an unprecedented trifluoromethoxymethyl ketone warhead. Compared with the marketed drug nirmatrelvir (combination with ritonavir = Paxlovid), CMX990 has distinctly differentiated potency (∼5× more potent in primary cells) and human in vitro clearance (>4× better microsomal clearance and >10× better hepatocyte clearance), with good in vitro-to-in vivo correlation. Based on its compelling preclinical profile and projected once or twice a day dosing supporting unboosted oral therapy in humans, CMX990 advanced to a Phase 1 clinical trial as an oral drug candidate for SARS-CoV-2.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Diferenciación Celular , Revelación , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasas/uso terapéutico , Antivirales/farmacología
18.
J Am Chem Soc ; 135(17): 6415-8, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23570328

RESUMEN

An efficient organocatalytic method for chemoselective aerobic oxidation of secondary benzylic alcohols within lignin model compounds has been identified. Extension to selective oxidation in natural lignins has also been demonstrated. The optimal catalyst system consists of 4-acetamido-TEMPO (5 mol %; TEMPO = 2,2,6,6-tetramethylpiperidine-N-oxyl) in combination with HNO3 and HCl (10 mol % each). Preliminary studies highlight the prospect of combining this method with a subsequent oxidation step to achieve C-C bond cleavage.


Asunto(s)
Alcohol Bencilo/química , Lignina/química , Aerobiosis , Bicarbonatos/química , Biopolímeros , Catálisis , Ácido Clorhídrico/química , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Metales/química , Modelos Químicos , Oxidación-Reducción
19.
Iran J Basic Med Sci ; 26(8): 891-898, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37427334

RESUMEN

Objectives: Due to the presence of the cholinergic system in the lateral periaqueductal gray (lPAG) column, the cardiovascular effects of acetylcholine (ACH) and its receptors in normotensive and hydralazine (HYD) hypotensive rats in this area were evaluated. Materials and Methods: After anesthesia, the femoral artery was cannulated and systolic blood pressure (SBP), mean arterial pressure (MAP), heart rate (HR), and also electrocardiogram for evaluation of low frequency (LF) and high frequency (HF) bands, important components of heart rate variability (HRV), were recorded. ACH, atropine (Atr, a muscarinic antagonist), and hexamethonium (Hex, an antagonist nicotinic) alone and together microinjected into lPAG, changes (Δ) of cardiovascular responses and normalized (n) LF, HF, and LF/HF ratio were analyzed. Results: In normotensive rats, ACH decreased SBP and MAP, and enhanced HR while Atr and Hex did had no effects. In co-injection of Atr and Hex with ACH, only ACH+Atr significantly attenuated parameters. In HYD hypotension, ACH had no affect but Atr and Hex significantly improved the hypotensive effect. Co-injection of Atr and Hex with ACH decreased the hypotensive effect but the effect of Atr+ACH was higher. In normotensive rats, ACH decreased nLF, nHF, and nLF/nHF ratio. These parameters in the Atr +ACH group were significantly higher than in ACH group. In HYD hypotension nLF and nLF/nHF ratio increased which was attenuated by ACH. Also, Atr+ACH decreased nLF and nLF/nHF ratio and increased nHF. Conclusion: The cholinergic system of lPAG mainly via muscarinic receptors has an inhibitory effect on the cardiovascular system. Based on HRV assessment, peripheral cardiovascular effects are mostly mediated by the parasympathetic system.

20.
Int J Inj Contr Saf Promot ; 30(4): 571-581, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37498113

RESUMEN

This research examines the injury severity of single-vehicle large-truck crashes in Florida while exploring the role of heterogeneity. A random parameter ordered logit (RPOL) model was applied to 27,505 single-vehicle large-truck crashes from 2007 to 2016 in Florida, and the contributing factors were identified. Random parameters and interaction effects were introduced to the model to determine the heterogeneity and its potential sources. The results suggested that driving speed of 76-120 mph and defective tires were the most influential factors in crash injury severity, increasing the probability of severe crashes. Regarding truckers' attributes, asleep or fatigued conditions and driving under the influence were correlated with a higher possibility of severe crashes. Interestingly, the results showed that truckers from outside the state of Florida were less likely to cause severe single-vehicle large-truck crashes compared to their Floridian counterparts. Y-intersections were also found as a high-risk location for single-vehicle large-truck crashes, leading to more severe outcomes. Regarding heterogeneity, the results indicated that the impacts of driving speed (26-50 mph) and light condition (dark - not lighted) significantly varied among the observations, and these variations could be attributed to driver action, vision obstruction, driver distraction, roadway type and roadway alignment.


Asunto(s)
Conducción Distraída , Heridas y Lesiones , Humanos , Accidentes de Tránsito , Vehículos a Motor , Modelos Logísticos
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