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1.
Artículo en Inglés | MEDLINE | ID: mdl-39218827

RESUMEN

Oral hormone replacement therapy has been and continues to be the cornerstone of adrenocortical insufficiency management. However, the introduction of continuous subcutaneous hydrocortisone infusion (CSHI) shows great potential for advancing the management of adrenocortical insufficiency. It resembles the circadian rhythm of physiological cortisol secretion and was shown to have a promising outcome in terms of quality of life (QOL) and clinical outcomes in the literature. We conducted a systematic search strategy including MEDLINE, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL), and the online trials registers at ClinicalTrials.gov without geographic restrictions. Research investigations where self-reported quality of life (QOL) was assessed as a variable in adult individuals with confirmed adrenal disease, treated by CSHI, and results were presented in English. All articles included were published between 2014 and 2023, even though we had no timeframe limitations in our inclusion criteria. A total of six studies were included, with 63 subjects enrolled, and the average age was 40 years, a study showed a significant reduction in the average total daily dose of HC from 47.5 mg to 31.4 mg on CSHI, while other two studies estimated a reduction in the hospitalization rate due to adrenal crisis from 2.6 to 1.3 admissions per year on CSHI. Most of the studies on subjective well-being and quality of life have shown significant improvement. Overall, CSHI shows great potential as a treatment method for Adrenal insufficiency. It improves the quality of life and lowers hospitalization rates, resulting in increased patient satisfaction and acceptance. Additional comprehensive research is necessary to strengthen these discoveries, gain a deeper understanding of the effectiveness and safety of this treatment approach, and provide guidance for medical practitioners.

2.
Med Sci Monit ; 30: e943218, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38173221

RESUMEN

BACKGROUND Physicians are faced with the risk of patients developing opioid use disorders (OUDs) when prescribing patients opioids for long periods of time. Therefore, it is highly recommended to continuously monitor and evaluate long-term non-cancer pain patients who are prescribed opioids. This study aims to estimate the prevalence of OUDs in 103 patients with active opioid prescriptions attending the Pain Clinic at King Khalid University Hospital. MATERIAL AND METHODS A cross-sectional study was conducted at King Khalid University Hospital's pain clinic from 2020 to 2022. A list of all patients attending the Pain Clinic with an opioid prescription was provided by the hospital. Through telephone interviews, consent was secured followed by the collection of demographic variables and prescription-related variables. Additionally, patients were asked to complete the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST 3.1) opioid questionnaire. RESULTS Most of the 103 patients were at moderate risk for abuse (91.3%), while a smaller percentage were at high risk (dependence) (5.8%) and low risk (misuse) (2.9%). Tramadol was the most-prescribed opioid (43.7%). Young age (<50) (Z=2.534; P=0.011), opioid use for more than 90 days (Z=2.788; P=0.005), and the prescription of tramadol (Z=4.124; P<0.001) were associated with higher risk of OCDs. CONCLUSIONS Younger patients, opioid use >90 days, and tramadol are associated with a higher risk of opioid misuse. However, further studies on a larger scale and in various settings are needed to provide evidence accurately reflecting the general population, as this study focused on the population of pain clinic attendees.


Asunto(s)
Trastornos Relacionados con Opioides , Tramadol , Humanos , Analgésicos Opioides/efectos adversos , Estudios Transversales , Clínicas de Dolor , Trastornos Relacionados con Opioides/epidemiología , Trastornos Relacionados con Opioides/tratamiento farmacológico , Hospitales Universitarios , Factores de Riesgo
3.
J Stroke Cerebrovasc Dis ; 33(4): 107552, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38277959

RESUMEN

PURPOSE: This study aimed to investigate the outcomes of endovascular thrombectomy-treated patients in King Fahad Medical City, Riyadh, Saudi Arabia. METHODS: A retrospective cohort study of acute ischemic stroke patients treated with endovascular thrombectomy. Patients were included in the study between January 2015 and December 2022. Good outcomes were defined as a modified Rankin Scale (mRS) of 0-2 at 90 days. Multivariate logistic regression analysis was performed to identify the independent factors associated with good outcomes. RESULTS: During the study period, 369 patients with acute ischemic stroke (mean ± SD age, 61/- 15.1 yrs; 55.4 % male) underwent mechanical thrombectomy. Median National Institute of Health Stroke Scale (NIHSS) 15. Intravenous thrombolysis was administered to 34.5 % of the patients. Successful recanalization in the anterior circulation was achieved in 84.8 % of patients. Data from mRS performed after 90 days in the anterior circulation were available for 71.2 % of the patients. Of these, 41 % showed a good outcome, and the mortality rate was 22.4 %. The significant factors associated with good outcomes were age, NIHSS score, Alberta Stroke Program Early Computed Tomography Score (ASPECTS), and short arterial puncture to recanalization. CONCLUSION: The number of patients who underwent endovascular thrombectomy has increased over time. The treatment outcomes and mortality were comparable with those of previous endovascular thrombectomy registries despite the high prevalence of DM, lower ASPECT score, and prolonged onset-to-recanalization time.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Masculino , Femenino , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Accidente Cerebrovascular Isquémico/terapia , Estudios Retrospectivos , Arabia Saudita , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/terapia , Trombectomía/efectos adversos , Trombectomía/métodos , Resultado del Tratamiento , Procedimientos Endovasculares/efectos adversos , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/terapia
4.
Int J Mol Sci ; 25(16)2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39201258

RESUMEN

The Middle Eastern prevalence of sickle cell anemia, a genetic disorder that affects red blood cells, necessitates additional research. On a molecular level, we sought to identify and sort the oral microbiota of healthy individuals and those with sickle cell anemia. Furthermore, it is crucial to comprehend how changes in the genetic makeup of the oral microbiota impact the state of sickle cell anemia. Using next-generation sequencing, the 16S rRNA amplicon was examined using saliva samples from 36 individuals with sickle cell anemia and healthy individuals. These samples were obtained from sickle cell anemia patients (18 samples) and healthy control participants (controls, 18 samples). Various analyses are conducted using bioinformatic techniques to identify distinct species and their relative abundance. Streptococcus, followed by Fusobacterium nucleatum, Prevotella, and Veillonella were the most prevalent genera of bacteria in the saliva of the SCA and non-SCA individuals according to our findings. Rothia mucilaginosa, Prevotella scoposa, and Veillonella dispar species were the dominant species in both sickle cell anemia and non-sickle cell anemia subjects. Streptococcus salivarius, Actinomyces graevenitzii, Actinomyces odontolyticus, and Actinomyces georgiae spp. were the most prevalent bacterial spp. in the studied SCA cases. The sequencing of the 16S rRNA gene yielded relative abundance values that were visualized through a heatmap analysis. Alterations in the oral microflora's constitution can significantly affect the susceptibility of sickle cell anemia patients to develop more severe health complications. Salivary diagnosis is a potential tool for predicting and preventing oral microbiome-related diseases in the future.


Asunto(s)
Anemia de Células Falciformes , Microbiota , Boca , ARN Ribosómico 16S , Saliva , Humanos , Anemia de Células Falciformes/microbiología , Anemia de Células Falciformes/genética , Boca/microbiología , Microbiota/genética , ARN Ribosómico 16S/genética , Femenino , Masculino , Adulto , Saliva/microbiología , Bacterias/genética , Bacterias/clasificación , Bacterias/aislamiento & purificación , Adulto Joven , Estudios de Casos y Controles , Adolescente , Secuenciación de Nucleótidos de Alto Rendimiento , Persona de Mediana Edad
5.
Toxicol Appl Pharmacol ; 466: 116449, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36924898

RESUMEN

Intensive and inefficient exploitation of pesticides through modernized agricultural practices has caused severe pesticide contamination problems to the environment and become a crucial problem over a few decades. Due to their highly toxic and persistent properties, they affect and get accumulated in non-target organisms, including microbes, algae, invertebrates, plants as well as humans, and cause severe issues. Considering pesticide problems as a significant issue, researchers have investigated several approaches to rectify the pesticide contamination problems. Several analyses have provided an extensive discussion on pesticide degradation but using specific technology for specific pesticides. However, in the middle of this time, cleaner techniques are essential for reducing pesticide contamination problems safely and environmentally friendly. As per the research findings, no single research finding provides concrete discussion on cleaner tactics for the remediation of contaminated sites. Therefore, in this review paper, we have critically discussed cleaner options for dealing with pesticide contamination problems as well as their advantages and disadvantages have also been reviewed. As evident from the literature, microbial remediation, phytoremediation, composting, and photocatalytic degradation methods are efficient and sustainable and can be used for treatment at a large scale in engineered systems and in situ. However, more study on the bio-integrated system is required which may be more effective than existing technologies.


Asunto(s)
Plaguicidas , Humanos , Plaguicidas/metabolismo , Agricultura , Biodegradación Ambiental , Tecnología
6.
J Endovasc Ther ; : 15266028231184687, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37401667

RESUMEN

OBJECTIVE: The main objective of this study is to present the experience of 2 centers undertaking total percutaneous aortic arch-branched graft endovascular repair using combination of femoral and axillary routes. The report summarizes the procedural steps, outcomes achieved, and the benefits of this approach, which eliminates the need for direct open surgical exposure of the carotid, subclavian, or axillary arteries, thereby reducing the unnecessary associated surgical risks. METHODS: Retrospectively collected data of 18 consecutive patients (15M:3F) undergoing aortic arch endovascular repair using a branched device between February 2021 and June 2022 at 2 aortic units. Six patients were treated for a residual aortic arch aneurysm following previous type A dissection with size range of (58-67 mm in diameter), 10 were treated for saccular or fusiform degenerative atheromatous aneurysm with size range of (51.5-80 mm in diameter), and 2 were treated for penetrating aortic ulcer (PAU) with size range of (50-55 mm). Technical success was defined as completion of the procedure and satisfactory placement of the bridging stent grafts (BSGs) in the supra-aortic vessels percutaneously including the brachiocephalic trunk (BCT), left common carotid artery (LCCA), and left subclavian artery (LSA) without the need for carotid, subclavian, or axillary cut down. The primary technical success was examined as primary outcome well as any other related complications and reinterventions as secondary outcomes. RESULTS: The primary technical success with our alternative approach was achieved in all 18 cases. There was one access site complication (groin haematoma), which was managed conservatively. There was no incidence of death, stroke, or cases of paraplegia. No other immediate complications were noted. Postoperative imaging confirmed supra-aortic branch patency, with satisfactory position of the BSGs and immediate aneurysm exclusion except in 4 patients who had type 1C endoleak (Innominate: 2, LSA 2) detected on the first postoperative scan. Three of them were treated with relining/extension, and 1 spontaneously resolved after 6 weeks. CONCLUSIONS: Total percutaneous aortic arch repair with antegrade and retrograde inner-branch endografts can be performed with promising early results. Dedicated steerable sheaths and appropriate BSG would optimize the percutaneous approach for aortic arch endovascular repairs. CLINICAL IMPACT: This article provides an alternative and innovative approach to improve the minimally invasive techniques in the endovascular treatment of the aortic arch conditions.

7.
BMC Public Health ; 23(1): 1462, 2023 07 31.
Artículo en Inglés | MEDLINE | ID: mdl-37525238

RESUMEN

BACKGROUND: Intermittent fasting (IF) is a popular dietary plan for weight loss. In fact, fasting is a common practice in different religions such as Buddhism, Hinduism, Judaism, Christianity, and Islam. During the month of Ramadan, more than 1.5 billion Muslims worldwide fast from dawn to sunset. Ramadan diurnal intermittent fasting (RDIF) has health benefits, including a reduction in cardiovascular disease (CVD) risk and an improvement in mood. However, little is known about the effects of RDIF on lifestyle behaviors, such as regular exercise, consuming healthy diet, and avoiding harmful substances, as well as mental stress, and academic performance in high school and university students. METHODS: In this prospective cohort study, two self-reported questionnaires were sent one week before and during the last week of Ramadan (April 2022; Ramadan 1443 in Hijri Islamic Calendar) to assess changes in lifestyle, perceived stress, and academic achievement of medical students at Taif University in Taif city, Saudi Arabia. Healthy lifestyle components data were collected to calculate healthy lifestyle scores, including body mass index, physical activity, adherence to a Mediterranean diet, smoking status, and sleep duration. RESULTS: RDIF was associated with a healthier lifestyle in both female and male participants (pre-RDIF mean score: 2.42 vs post-RDIF mean score: 2.74; statistical power = 0.99; P-value < 0.05). They were more active and adherent to the Mediterranean diet during RDIF. Additionally, the post-RDIF smoking rate declined by 53.4%. Male participants showed higher perceived stress scores during RDIF (pre-RDIF mean score: 19.52 vs post-RDIF mean score: 22.05; P-value < 0.01). No changes in academic performance were observed upon RDIF. CONCLUSION: Medical students show healthier dietary and lifestyle behaviors and their academic performance is not affected during RDIF. However, perceived stress is higher among male students.


Asunto(s)
Ayuno , Estudiantes de Medicina , Humanos , Masculino , Femenino , Ayuno Intermitente , Estudios Prospectivos , Arabia Saudita , Estilo de Vida , Estrés Psicológico/epidemiología , Islamismo
8.
Saudi Pharm J ; 31(5): 736-745, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37181143

RESUMEN

The current study was designed to develop a nanoconjugate of cordycepin-melittin (COR-MEL) and assess its healing property in wounded diabetic rats. The prepared nanoconjugate has a particle size of 253.5 ± 17.4 nm with a polydispersity index (PDI) of 0.35 ± 0.04 and zeta potential of 17.2 ± 0.3 mV. To establish the wound healing property of the COR-MEL nanoconjugate, animal studies were pursued, where the animals with diabetes were exposed to excision and treated with COR hydrogel, MEL hydrogel, or COR-MEL nanoconjugate topically. The study demonstrated an accelerated wound contraction in COR-MEL nanoconjugate -treated diabetic rats, which was further validated by histological analysis. The nanoconjugate further exhibited antioxidant activities by inhibiting the accumulation of malondialdehyde (MDA) and exhaustion of superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzymatic activities. The nanoconjugate further demonstrated an enhanced anti-inflammatory activity by retarding the expression of interleukin (IL)-6 and tumor necrosis factor (TNF)-α. Additionally, the nanoconjugate exhibits a strong expression of transforming growth factor (TGF)-ß1, vascular endothelial growth factor (VEGF)-A, and platelet-derived growth factor (PDGFR)-ß, indicating enrichment of proliferation. Likewise, nanoconjugate increased the concentration of hydroxyproline as well as the mRNA expression of collagen, type I, alpha 1 (Col 1A1). Thus, it is concluded that the nanoconjugate possesses a potent wound-healing activity in diabetic rats via antioxidant, anti-inflammatory, and pro-angiogenetic mechanisms.

9.
Int J Clin Pract ; 2022: 5846255, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35989869

RESUMEN

Introduction: The temporomandibular joint is a complex synovial joint in the body. It is the area in which the mandible articulates with the cranium. The temporomandibular joint space is located between the articular eminence and the glenoid fossa of the temporal bone at the base of the skull and the condylar process of the mandible. This interarticular space is divided into superior joint space (1.2 ml) and inferior joint space (0.9 ml) by the articular disc. The purpose of this study is to detect and evaluate the variations in the temporomandibular joint space among patients having temporomandibular joint disorders. Materials and Methods: In this retrospective study, 60 magnetic resonance imaging scans were evaluated at King Faisal Specialist Hospital in Riyadh, Saudi Arabia, between the years 2006 and 2016. Measurements were done in sagittal view in three areas: anterior, central, and posterior areas. However, coronal view readings were recorded in two different areas: medial and lateral joint spaces. All measurements were recorded at the highest point of the condyle that is perpendicular to the opposing bone. The SPSS program was used for statistical analysis. Results: The central joint space values were higher than the anterior and posterior joint spaces in both coronal and sagittal views. We also found that joint spaces among male patients were higher than female patients (right side P=0.015 and left side P=0.006). It is worth mentioning that the number of temporomandibular joint disorder female patients was more than the number of male temporomandibular joint disorder patients (52 females versus 24 males). Additionally, patients who were older than 55 years old had wider joint spaces than patients who were younger than 25 years old. Conclusion: The central joint space value was the highest among the other joint spaces on both views of magnetic resonance imaging, and the values of joint spaces among males were larger than those of females on sagittal magnetic resonance imaging. Patients with elderly temporomandibular joint disorders showed larger joint spaces than young patients. This study spotlights the importance of magnetic resonance imaging evaluation in temporomandibular joint disorder patients for a better understanding of the clinical evolution of temporomandibular disorders.


Asunto(s)
Disco de la Articulación Temporomandibular , Trastornos de la Articulación Temporomandibular , Adulto , Anciano , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Cóndilo Mandibular/patología , Persona de Mediana Edad , Estudios Retrospectivos , Arabia Saudita , Articulación Temporomandibular/diagnóstico por imagen , Articulación Temporomandibular/patología , Disco de la Articulación Temporomandibular/patología , Trastornos de la Articulación Temporomandibular/diagnóstico por imagen , Trastornos de la Articulación Temporomandibular/patología
10.
Sensors (Basel) ; 22(22)2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36433326

RESUMEN

Modern wheelchairs, with advanced and robotic technologies, could not reach the life of millions of disabled people due to their high costs, technical limitations, and safety issues. This paper proposes a gesture-controlled smart wheelchair system with an IoT-enabled fall detection mechanism to overcome these problems. It can recognize gestures using Convolutional Neural Network (CNN) model along with computer vision algorithms and can control the wheelchair automatically by utilizing these gestures. It maintains the safety of the users by performing fall detection with IoT-based emergency messaging systems. The development cost of the overall system is cheap and is lesser than USD 300. Hence, it is expected that the proposed smart wheelchair should be affordable, safe, and helpful to physically disordered people in their independent mobility.


Asunto(s)
Personas con Discapacidad , Silla de Ruedas , Humanos , Gestos , Dedos , Redes Neurales de la Computación
11.
Molecules ; 27(17)2022 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-36080245

RESUMEN

The synthesis of MMT and poly(o-anisidine) (MMT/POA) clay nanocomposites was carried out by using the chemical oxidative polymerization of POA and MMT clay with POA, respectively. By maintaining the constant concentration of POA, different percentage loads of MMT clay were used to determine the effect of MMT clay on the properties of POA. The interaction between POA and MMT clay was investigated by FTIR spectroscopy, and, to reveal the complete compactness and homogeneous distribution of MMT clay in POA, were assessed by using scanning-electron-microscope (SEM) analysis. The UV-visible spectrum was studied for the optical and absorbance properties of MMT/POA ceramic nanocomposites. Furthermore, the horizontal burning test (HBT) demonstrated that clay nanofillers inhibit POA combustion.


Asunto(s)
Retardadores de Llama , Nanocompuestos , Compuestos de Anilina , Bentonita/química , Arcilla , Nanocompuestos/química
12.
Hosp Pharm ; 56(6): 690-696, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34732923

RESUMEN

OBJECTIVE: Prescribing a drug for a child is not an easy task and requires using the best available evidence as a guide, especially when a drug is used off-label. The practice of prescribing a drug for off-label use is fairly widespread worldwide. The FDA does not regulate prescribing patterns or practices of individual practitioners and, therefore, allows off-label use. The main objective of this study is to evaluate off-label prescribing among the pediatric population in the Kingdom of Saudi Arabia (KSA). METHOD: This is a retrospective, simple random selection observational study of children (≤15 years) who visited pediatric clinics and had at least 1 drug prescribed over a 12-month period (January to December 2018). RESULTS: A total of 865 drugs (mean 1 and SD 0.24) were prescribed to 326 children. Off-label was identified in 39.4% of the drugs with a frequency of 512 (as 1 drug may belong to more than 1 off-label category). The most common reason for off-label prescribing was related to doses that were "higher or lower than the recommended use" (48.6%), and the most frequently identified drug class prescribed for off-label use was anti-infective drugs for systemic use (39.9%). The percentage of off-label drug use was found to be higher in girls and in the age group of 1 month to 2 years (P = .001) for both variables. In addition, a significant association was found between off label drug use and the total number of drugs prescribed, P < .001. CONCLUSION: The findings of this study showed a high incidence of off-label prescribing mainly related to dosing and indication. The results of this observational study support the need to establish a unified national pediatric dosing formulary guide to ensure safe drug use in pediatrics.

13.
Clin Genet ; 97(3): 447-456, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31730227

RESUMEN

Retinal arterial macroaneurysms with supravalvular pulmonic stenosis (RAMSVPS), also known as Familial Retinal Arterial Macroaneurysms (FRAM) syndrome, is a very rare multisystem disorder. Here, we present a case series comprising ophthalmologic and systemic evaluation of patients homozygous for RAMSVPS syndrome causative IGFBP7 variant. New clinical details on 22 previously published and 8 previously unpublished patients are described. Age at first presentation ranged from 1 to 34 years. The classical feature of macroaneurysms and vascular beading involving the retinal arteries was universal. Follow up extending up to 14 years after initial diagnosis revealed recurrent episodes of bleeding and leakage from macroaneurysms in 55% and 59% of patients, respectively. The majority of patients who underwent echocardiography (18/23) showed evidence of heart involvement, most characteristically pulmonary (valvular or supravalvular) stenosis, often requiring surgical correction (12/18). Four patients died in the course of the study from complications of pulmonary stenosis, cerebral hemorrhage, and cardiac complications. Liver involvement (usually cirrhosis) was observed in eight patients. Cerebral vascular involvement was observed in one patient, and stroke was observed in two. We conclude that RAMSVPS is a recognizable syndrome characterized by a high burden of ocular and systemic morbidity, and risk of premature death. Recommendations are proposed for early detection and management of these complications.


Asunto(s)
Predisposición Genética a la Enfermedad , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/genética , Estenosis de la Válvula Pulmonar/genética , Macroaneurisma Arterial de Retina/genética , Adolescente , Adulto , Niño , Preescolar , Femenino , Angiografía con Fluoresceína , Fondo de Ojo , Homocigoto , Humanos , Lactante , Masculino , Estenosis de la Válvula Pulmonar/complicaciones , Estenosis de la Válvula Pulmonar/diagnóstico por imagen , Estenosis de la Válvula Pulmonar/patología , Macroaneurisma Arterial de Retina/complicaciones , Macroaneurisma Arterial de Retina/diagnóstico por imagen , Macroaneurisma Arterial de Retina/patología , Arteria Retiniana/diagnóstico por imagen , Arteria Retiniana/metabolismo , Arteria Retiniana/patología , Agudeza Visual/genética , Agudeza Visual/fisiología , Adulto Joven
14.
Langmuir ; 35(1): 41-50, 2019 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-30509072

RESUMEN

Over the past few decades, field- and laboratory-scale studies have shown enhancements in oil recovery when reservoirs, which contain high-salinity formation water (FW), are waterflooded with modified-salinity salt water (widely referred to as the low-salinity, dilution, or SmartWater effect for improved oil recovery). In this study, we investigated the time dependence of the physicochemical processes that occur during diluted seawater (i.e., SmartWater) waterflooding processes of specific relevance to carbonate oil reservoirs. We measured the changes to oil/water/rock wettability, surface roughness, and surface chemical composition during SmartWater flooding using 10-fold-diluted seawater under mimicked oil reservoir conditions with calcite and carbonate reservoir rocks. Distinct effects due to SmartWater flooding were observed and found to occur on two different timescales: (1) a rapid (<15 min) increase in the colloidal electrostatic double-layer repulsion between the rock and oil across the SmartWater, leading to a decreased oil/water/rock adhesion energy and thus increased water wetness and (2) slower (>12 h to complete) physicochemical changes of the calcite and carbonate reservoir rock surfaces, including surface roughening via the dissolution of rock and the reprecipitation of dissolved carbonate species after exchanging key ions (Ca2+, Mg2+, CO32-, and SO42- in carbonates) with those in the flooding SmartWater. Our experiments using crude oil from a carbonate reservoir reveal that these reservoir rock surfaces are covered with organic-ionic preadsorbed films (ad-layers), which the SmartWater removes (detaches) as flakes. Removal of the organic-ionic ad-layers by SmartWater flooding enhances oil release from the surfaces, which was found to be critical to increasing the water wetness and significantly improving oil removal from carbonates. Additionally, the increase in water wetness is further enhanced by roughening of the rock surfaces, which decreases the effective contact (interaction) area between the oil and rock interfaces. Furthermore, we found that the rate of these slower physicochemical changes to the carbonate rock surfaces increases with increasing temperature (at least up to an experimental temperature of 75 °C). Our results suggest that the effectiveness of improved oil recovery from SmartWater flooding depends strongly on the formation of the organic-ionic ad-layers. In oil reservoirs where the ad-layer is fully developed and robust, injecting SmartWater would lead to significant removal of the ad-layer and improved oil recovery.

15.
Gen Physiol Biophys ; 38(6): 497-503, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31829307

RESUMEN

Normal repeated uterine contractions are associated with uterine hypoxic stresses and uterine transplantation and severe bleeding during hysterectomy may lead to hypoxia and irreversible cellular damage. This study investigated the effects of short repeated hypoxic episodes on the structure and function of uterine tissues following sustained prolonged hypoxia. Small segments of uterine tissue were dissected from three groups of nonpregnant rats and mounted in a tissue bath system. Prolonged hypoxia markedly increased the infiltration of eosinophils into the myometrium and caused fibrotic stroma and degeneration of endometrial glands with marked infiltration of eosinophils into the endometrium compared to the control group. In addition, the mean myometrial contractile function significantly decreased to 69 ± 1% compared to 100% control with irregular and uncoordinated contractile activity (p < 0.01). Intriguingly, preconditioning with brief hypoxic episodes prevented the endometrial and myometrial degenerative changes. Although the mean myometrial contractile function decreased to 80 ± 3% during reoxygenation compared to the 100% control, the entire force was greater than the force in the non-preconditioned group (p < 0.01). These results provide compelling evidence that prolonged hypoxia exacerbates the degree of cellular damage and that preconditioning with repeated cycles of short hypoxia/reoxygenation can ameliorate cellular damage.


Asunto(s)
Hipoxia , Miometrio , Animales , Endometrio , Femenino , Contracción Muscular , Embarazo , Ratas , Útero
16.
J Adolesc ; 71: 63-71, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30639665

RESUMEN

Puberty is a physiological event involving the attainment of reproductive capability and complete development of sexual and physical organs. Changing from childhood to adulthood is a complex process and is tightly controlled by interconnection pathways at the level of the hypothalamus which can be influenced by environmental, psychosocial, and endocrine factors. Although various mechanisms underlying the onset of normal puberty have been investigated in humans and animals, the exact molecular mechanisms thereof remain unclear. The aim of this review is to summarize the current state of knowledge and provide a synoptic overview about the physiology of puberty in adolescent boys and girls, and describe pathological disorders affecting its onset.


Asunto(s)
Pubertad/fisiología , Maduración Sexual/fisiología , Adolescente , Trastornos del Desarrollo Sexual/fisiopatología , Femenino , Humanos , Masculino , Caracteres Sexuales
17.
Proc Natl Acad Sci U S A ; 112(31): 9763-8, 2015 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-26195731

RESUMEN

For successful birth, contractions need to become progressively stronger. The underlying mechanisms are unknown, however. We have found that a novel mechanism, hypoxia-induced force increase (HIFI), is switched on selectively, at term, and is essential to strengthening contractions. HIFI is initiated as contractions cyclically reduce blood flow and produce repeated hypoxic stresses, with associated metabolic and transcriptomic changes. The increases in contractility are a long-lasting, oxytocin-independent, intrinsic mechanism present only in the full-term pregnant uterus. HIFI is inhibited by adenosine receptor antagonism and blockade of cyclooxygenase-2 signaling, and partially reproduced by brief episodes of acidic (but not alkalotic) pH. HIFI explains how labor can progress despite paradoxical metabolic challenge, and provides a new mechanistic target for the 1 in 10 women suffering dysfunctional labor because of poor contractions.


Asunto(s)
Hipoxia/fisiopatología , Trabajo de Parto , Estrés Fisiológico , Contracción Uterina/fisiología , Ácidos/metabolismo , Adaptación Fisiológica/efectos de los fármacos , Adenosina/farmacología , Adenosina Trifosfato/farmacología , Animales , Fenómenos Biomecánicos/efectos de los fármacos , Calcio/farmacología , Ciclooxigenasa 2/metabolismo , Femenino , Humanos , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Trabajo de Parto/efectos de los fármacos , Miometrio/efectos de los fármacos , Miometrio/fisiopatología , Oxígeno/farmacología , Oxitocina/farmacología , Embarazo , Ratas Wistar , Receptor de Adenosina A1/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Estrés Fisiológico/efectos de los fármacos , Contracción Uterina/efectos de los fármacos
18.
Croat Med J ; 59(6): 327-334, 2018 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-30610775

RESUMEN

AIM: To assess the in vitro effect of hydrogen peroxide (H2O2) on uterine contractions in pregnant and non-pregnant rats. METHODS: The study was performed at the Department of Physiology, College of Medicine, King Saud University from December 2016 to October 2017. Intact uterine samples were obtained from non-pregnant (n=7-8) and term-pregnant (n=6-7) rats. Small longitudinal uterine strips were dissected and mounted in an organ bath. Isometric force measurements were used to assess the effect of 400, 800, and 1000 µM H2O2 on spontaneous uterine contractions and contractions induced by oxytocin (5 nM), high calcium (Ca+2) solution (6 mmol/L), and high potassium chloride (KCl) solution (60 mmol/L). RESULTS: In both term-pregnant and non-pregnant uterine strips, H2O2 elicited a biphasic response, consisting of a transient contraction followed by a persistent decrease in spontaneously generated contractions, contractions induced by oxytocin, and contractions induced by high Ca+2 (all P<0.01, compared with controls) in a concentration-dependent manner. The effect of H2O2 was more pronounced in non-pregnant than in pregnant rats (P<0.05). In both groups, H2O2 failed to relax uterine strips pre-contracted with high-KCl solution (P>0.05 compared with controls). CONCLUSION: H2O2 was shown to be a potent uterine relaxant in pregnant and non-pregnant states. The pregnant uterus better withstood the inhibitory effect of H2O2 than non-pregnant uterus.


Asunto(s)
Peróxido de Hidrógeno/farmacología , Oxidantes/farmacología , Contracción Uterina/efectos de los fármacos , Animales , Calcio/farmacología , Femenino , Oxitócicos/farmacología , Oxitocina/farmacología , Cloruro de Potasio/farmacología , Embarazo , Ratas , Ratas Wistar , Técnicas de Cultivo de Tejidos
19.
Int Orthop ; 42(8): 1979-1985, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29387916

RESUMEN

PURPOSE: The purpose of the study is to provide a methodology to quantify knee height asymmetry (KHA) and to establish the incidence of knee height asymmetry in a patient population visiting the limb length discrepancy clinic in a paediatric-orthopaedic hospital centre. METHOD: A retrospective chart review was performed on all patients who attended the limb length discrepancy clinic and underwent corrective surgery at the Shriners Hospital for Children-Canada from December 2009 to December 2015. Full-standing anteroposterior radiographs were used to measure pre- and post-surgery limb length discrepancy and knee height asymmetry for 52 individuals included in the study. RESULTS: Sixty-seven percent of the studied population had a KHA of 20 mm or less, 25% had a KHA between 20 and 40 mm, and 8% had a KHA of over 40 mm. The average KHA preoperatively for all 52 individuals was 17 ± 14 mm (range 0-59 mm), which represents roughly 2.5% of total limb length. There was a 3-mm non-significant reduction in KHA size between pre-and post-operative states (p = 0.22). CONCLUSION: The current study provides a method to quantify knee height asymmetry. Using this method, it was shown that knee height asymmetry is frequent in youth with limb length discrepancy in both pre- and post-corrective surgery states. The relatively high incidence of knee height asymmetry highlights the importance to investigate the impact of knee height asymmetry in youth living with a limb length discrepancy.


Asunto(s)
Deformidades Adquiridas de la Articulación/epidemiología , Articulación de la Rodilla/diagnóstico por imagen , Diferencia de Longitud de las Piernas/complicaciones , Adolescente , Niño , Femenino , Humanos , Incidencia , Deformidades Adquiridas de la Articulación/etiología , Diferencia de Longitud de las Piernas/cirugía , Masculino , Estudios Retrospectivos
20.
Foot Ankle Surg ; 24(2): 119-123, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29409229

RESUMEN

BACKGROUND: Despite being a common condition, there are no objective measures in the literature to reflect the burden of pes planus on affected individuals. Our primary objective was to evaluate this burden by recruiting a sample from the general population using validated utility outcome measures. METHODS: Participants were recruited online and filled a questionnaire to help measure the health burden of pes planus. Three recognized utility outcome scores were used to compare the health burden of monocular blindness, binocular blindness, and pes planus. These included the standard gamble (SG), time trade-off (TTO), and visual analogue score (VAS). Paired t test, independent t test, and linear regression were used for statistical analysis. RESULTS: Ninety-two participants were included in the final analysis. The utility outcome scores (VAS, TTO, SG) for pes planus were 73±17, 0.90±0.08, and 0.88±0.12, respectively. The linear regression analysis showed that age was inversely proportional to the time trade-off. However, race, educational level, and income were not significant predictors of utility outcome score for pes planus. CONCLUSIONS: This study shows that the perceived burden of living with pes planus is comparable to living with some debilitating conditions. Our participants were willing to sacrifice 3.6 years of life, and have a procedure with a theoretical 12% mortality risk to attain perfect health.


Asunto(s)
Costo de Enfermedad , Pie Plano/epidemiología , Pie Plano/psicología , Indicadores de Salud , Evaluación del Resultado de la Atención al Paciente , Adolescente , Adulto , Femenino , Pie Plano/cirugía , Humanos , Masculino , Psicometría/métodos , Adulto Joven
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