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1.
Curr Issues Mol Biol ; 45(11): 9039-9059, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37998744

RESUMEN

Wound healing is a multifaceted process necessitating the collaboration of numerous elements to mend damaged tissue. Plant and animal-derived natural compounds have been utilized for wound treatment over the centuries, with many scientific investigations examining these compounds. Those with antioxidant, anti-inflammatory, and antibacterial properties are particularly noteworthy, as they target various wound-healing stages to expedite recovery. Thymoquinone, derived from Nigella sativa (N. sativa)-a medicinal herb with a long history of use in traditional medicine systems such as Unani, Ayurveda, Chinese, and Greco-Arabic and Islamic medicine-has demonstrated a range of therapeutic properties. Thymoquinone exhibits antimicrobial, anti-inflammatory, and antineoplastic activities, positioning it as a potential remedy for skin pathologies. This review examines recent research on how thymoquinone accelerates wound healing and the mechanisms behind its effectiveness. We carried out a comprehensive review of literature and electronic databases, including Google Scholar, PubMed, Science Direct, and MedlinePlus. Our aim was to gather relevant papers published between 2015 and August 2023. The main criteria for inclusion were that the articles had to be peer reviewed, original, written in English, and discuss the wound-healing parameters of thymoquinone in wound repair. Our review focused on the effects of thymoquinone on the cellular and molecular mechanisms involved in wound healing. We also examined the role of cytokines, signal transduction cascades, and clinical trials. We found sufficient evidence to support the effectiveness of thymoquinone in promoting wound healing. However, there is no consensus on the most effective concentrations of these substances. It is therefore essential to determine the optimal treatment doses and the best route of administration. Further research is also needed to investigate potential side effects and the performance of thymoquinone in clinical trials.

2.
BMC Ophthalmol ; 23(1): 194, 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37138239

RESUMEN

BACKGROUND: Keratoconus (KC) is easily recognized by its unique topographic pattern, but it can be difficult to distinguish subclinical form of the disease from the normal cornea. Optovue anterior segment optical coherence tomography (AS-OCT) helps diagnose KC. AIM OF THE WORK: To assess and the level of agreement of Keratometry-readings (K), Central Corneal Thickness (CCT) and Thinnest Corneal Thickness (TCT) measurements obtained by Optovue AS-OCT and Wavelight Oculyzer Pentacam HR in two groups: KC eyes and normal eyes. PATIENTS AND METHODS: This is a prospective clinical observational study. The study included 110 eyes divided into two groups. The study group included 62 eyes with topographic evidence of KC. The control group included 48 eyes of normal subjects with no topographic evidence of KC. All of the participants underwent full cycloplegic refraction, spectacle best-corrected distance visual acuity, comprehensive slit-lamp biomicroscopy and fundoscopy. All participants underwent corneal topography by Pentacam HR and AS-OCT. RESULTS: There were highly significant differences between the studied groups as regarding BCVA, intraocular pressure and CCT measurements which were found to be lower among KC group compared to the control one. There were highly significant differences between the studied groups regarding TCT measurement detected by Pentacam HR and AS-OCT which was found to be lower among the keratoconus group compared to the control one (470.9, 455.7 versus 541.9 and 518.7 respectively). CONCLUSION: Both Scheimpflug-based imaging and AS-OCT provide comparable readings with a good agreement regarding corneal pachymetry in keratoconus group with accurate identification of KC eyes and healthy ones. However, there was a significant difference in K readings between both devices in Keratoconus and control group.


Asunto(s)
Córnea , Paquimetría Corneal , Queratocono , Humanos , Córnea/diagnóstico por imagen , Paquimetría Corneal/métodos , Topografía de la Córnea/métodos , Queratocono/diagnóstico , Estudios Prospectivos , Reproducibilidad de los Resultados , Tomografía de Coherencia Óptica/métodos
3.
Sensors (Basel) ; 22(20)2022 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-36298297

RESUMEN

Recently, global healthcare has made great progress with the use of Internet of Things technology. However, for there to be excellent patient care, there must be a high degree of safety for the IoT health system. There has been a massive increase in hacking systems and the theft of sensitive and highly confidential information from large health centers and hospitals. That is why establishing a highly secure and reliable healthcare system has become a top priority. In this paper, a security scheme for the IoT-enabled healthcare environment, LBSS, is proposed. This security scheme comprises three security mechanisms. The first mechanism is based on the blockchain technology and is used for transaction integrity. The second mechanism is used to store the healthcare system data in a secure manner through the distribution of its data records among multiple servers. The third mechanism is used to access the healthcare data after applying a proposed authorization test. To minimize the security overhead, the healthcare data is prioritized in regard to its importance. Therefore, each security mechanism has specific steps for each level of data importance. Finally, the NS3 package is used to construct a simulation environment for IoT-enabled healthcare systems to measure the proposed security scheme performance. The simulation results proved that the proposed healthcare security scheme outperformed the traditional models in regard to the performance metrics.


Asunto(s)
Cadena de Bloques , Humanos , Seguridad Computacional , Confidencialidad , Atención a la Salud/métodos
4.
Molecules ; 27(4)2022 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-35209201

RESUMEN

The need for biodegradable and biocompatible polymers is growing quickly, particularly in the biomedical and environmental industries. Cellulose acetate, a natural polysaccharide, can be taken from plants and modified with polycaprolactone to improve its characteristics for a number of uses, including biomedical applications and food packaging. Cellulose acetate-g-polycaprolactone was prepared by a three-step reaction: First, polymerization of ε-caprolactone via ring-opening polymerization (ROP) reaction using 2-hydroxyethyl methacrylate (HEMA) and functionalization of polycaprolactone(PCL) by introducing NCO on the hydroxyl end of the HEMA-PCL using hexamethyl lenediisocyanate(HDI) were carried out. Then, the NCO-HEMA-PCL was grafted onto cellulose acetate (using the "grafting to" method). The polycaprolactone grafted cellulose acetate was confirmed by FTIR, the thermal characteristics of the copolymers were investigated by DSC and TGA, and the hydrophobicity was analyzed via water CA measurement. Introducing NCO-PCL to cellulose acetate increased the thermal stability. The contact angle of the unreacted PCL was higher than that of cellulose acetate-g-PCL, and it increased when the chain length increased. The CA-g-PCL50, CA-g-PCL100, and CA-g-PCL200 showed very high inhibition zones for all three bacteria tested (E. coli, S. aureus, and P. aeruginosa).


Asunto(s)
Antibacterianos , Bacterias/crecimiento & desarrollo , Celulosa/análogos & derivados , Embalaje de Alimentos , Poliésteres , Polimerizacion , Antibacterianos/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Celulosa/síntesis química , Celulosa/química , Celulosa/farmacología , Poliésteres/síntesis química , Poliésteres/química , Poliésteres/farmacología
5.
Clin Infect Dis ; 72(10): e476-e483, 2021 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-32803236

RESUMEN

BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has caused substantial morbidity and mortality worldwide. Few reports exist in Latin America, a current epicenter of transmission. Here, we aim to describe the epidemiology and outcomes associated with coronavirus disease 2019 (COVID-19) in Honduras. METHODS: Baseline clinical and epidemiological information of SARS-CoV-2 reverse transcriptase polymerase chain reaction-confirmed cases detected between 17 March-4 May in the San Pedro Sula Metropolitan area was collected; for hospitalized cases, clinical data were abstracted. Logistic regression models were fit to determine the factors associated with hospitalization. RESULTS: We identified 877 COVID-19 cases, of which 25% (n = 220) were hospitalized. The 19-44-year age group (57.8%) and males (61.3%) were predominant in overall COVID-19 cases. Of the cases, 34% (n = 299) had at least 1 preexisting medical condition. Individuals aged 45-69 years (adjusted odds ratio [aOR] = 4.05; 95% confidence interval [CI], 2.85-5.76) or ≥70 years (aOR = 9.12; 95% CI, 5.24-15.86), of male sex (aOR = 1.72; 95% CI, 1.21-2.44), and those with a preexisting condition (aOR = 2.12; 95% CI, 1.43-3.14) had higher odds of hospitalization. Of inpatients, 50% were hospitalized more than 7 days. The median length of hospitalization was 13 days (interquartile range [IQR], 8-29) among individuals aged 19-44 years, and 17 days (IQR, 11-24.6) among those aged 45-69. Of the fatal cases, 42% occurred among adults under 60 years old. CONCLUSIONS: Our findings show that a high proportion of COVID-19 cases in Honduras occurred among younger adults, who also constituted a significant proportion of severe and fatal cases. Preexisting conditions were associated with severe outcomes independently from age and were highly prevalent in Honduran COVID-19 cases.


Asunto(s)
COVID-19 , Adulto , Anciano , Honduras/epidemiología , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , SARS-CoV-2 , Adulto Joven
6.
IUBMB Life ; 71(3): 310-320, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30468285

RESUMEN

Noncoding RNAs are emerging biomarkers for many diseases including diabetic retinopathy (DR). This study aimed to measure the expression levels of serum miR-20b, miR-17-3p, HOTAIR, and MALAT1 in DR patients. A total of 80 patients diagnosed as type 2 diabetes (T2D) and 81 healthy subjects were recruited in this study. T2D patients were divided into three groups: nondiabetic retinopathy (NDR) group (30 patients), nonproliferative diabetic retinopathy (NPDR) group (30 patients), and proliferative diabetic retinopathy (PDR) group (20 patients). Quantitative real-time polymerase chain reaction (PCR) was used to assess the expression of serum miR-20b, miR-17-3p, HOTAIR, and MALAT1. We found a significant decrease in serum miR-20b and a significant increase in serum HOTAIR and MALAT1 in NDR patients compared to healthy subjects. Also, we revealed a significant decrease in serum miR-20b and miR-17-3p and a significant increase in serum HOTAIR and MALAT1 in each of NPDR and PDR groups when compared with healthy subjects. Furthermore, we reported a significant decrease in miR-20b and miR-17-3p and a significant increase in HOTAIR and MALAT1in DR as well as in PDR patients when compared with NDR patients. However, on comparing NPDR with NDR patients, no significant difference was observed regarding the expression levels of miR-20b and miR-17-3p, in contrast, significant elevation of serum HOTAIR and MALAT1 was found in NPDR. Moreover, we observed a significant decrease in serum miR-20b and miR-17-3p and a significant increase in serum HOTAIR and MALAT1 in PDR group relative to NPDR group. Receiver operating characteristic (ROC) curve was used for evaluating the diagnostic value of the examined serum noncoding RNAs as novel biochemical indicators detecting severity of DR. Our analyses suggested that the examined serum noncoding RNAs may discriminate DR (PDR and NPDR) from NDR. Furthermore, these noncoding RNAs (less importantly miR-17) can be used as promising novel biomarkers for prediction DR severity, distinguishing PDR from NPDR patients. We can conclude that serum miR-20b, miR-17-3p, HOTAIR, and MALAT1 may be used as noninvasive biomarkers for screening of DR and early diagnosis of PDR. © 2018 IUBMB Life, 71(3):310-320, 2019.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Retinopatía Diabética/genética , MicroARNs/genética , ARN Largo no Codificante/genética , Adulto , Biomarcadores/sangre , Estudios de Casos y Controles , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/patología , Retinopatía Diabética/sangre , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/patología , Diagnóstico Precoz , Femenino , Regulación de la Expresión Génica , Humanos , Masculino , MicroARNs/sangre , Persona de Mediana Edad , Pronóstico , ARN Largo no Codificante/sangre , Curva ROC , Índice de Severidad de la Enfermedad
7.
Tunis Med ; 96(1): 76-79, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30324998

RESUMEN

Cranial nerves palsy associated with preeclampsia is reported in literature. Facial and abducens palsies were the most nerve disorders described. Only eleven cases have been reported in the literature. We report the case of a 27-years-old patient who presented abducens nerve palsy in immediately after the delivery of severe pre-eclampsia. No specific pathology was found. Symptoms of abducens nerve palsy have resolved spontaneously by controlling blood pressure after delivery.


Asunto(s)
Enfermedades del Nervio Abducens/diagnóstico , Preeclampsia/patología , Trastornos Puerperales/diagnóstico , Enfermedades del Nervio Abducens/etiología , Adulto , Cesárea , Diplopía/diagnóstico , Diplopía/etiología , Femenino , Humanos , Preeclampsia/diagnóstico , Preeclampsia/cirugía , Embarazo , Trastornos Puerperales/etiología , Índice de Severidad de la Enfermedad
8.
Chem Pharm Bull (Tokyo) ; 62(12): 1166-72, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25450624

RESUMEN

The aim of this work was to synthesize 4-acetamido-, 4-amino- and 4-oxo-6-substituted aminoquinazolines and to evaluate them as phosphoinositide 3-kinases (PI3Ks) inhibitors. The respective chemotype was designed based on combining the structural features of two previously reported scaffolds acting as potent PI3Kγ inhibitors, which are quinazoline derivatives and amino-heterocyclic derivatives. In vitro enzymatic assay at 10 µM against all the eight human PI3K isoforms showed that an unsubstituted benzamide group at position 6 and an acetyl group at N(4) gave the best inhibitory activity on PI3Kγ. Interestingly, compounds 5a and 5e showed a significant, inhibitory effect on Class II PI3K-C2γ. This is of high value since there are very few inhibitors for this isoform reported in the literature.


Asunto(s)
Inhibidores de las Quinasa Fosfoinosítidos-3 , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacología , Quinazolinas/síntesis química , Quinazolinas/farmacología , Dominio Catalítico , Diseño de Fármacos
9.
NPJ Comput Mater ; 10(1): 224, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39309403

RESUMEN

Accurate computation of the gas adsorption properties of MOFs is usually bottlenecked by the DFT calculations required to generate partial atomic charges. Therefore, large virtual screenings of MOFs often use the QEq method which is rapid, but of limited accuracy. Recently, machine learning (ML) models have been trained to generate charges in much better agreement with DFT-derived charges compared to the QEq models. Previous ML charge models for MOFs have all used training sets with less than 3000 MOFs obtained from the CoRE MOF database, which has recently been shown to have high structural error rates. In this work, we developed a graph attention network model for predicting DFT-derived charges in MOFs where the model was developed with the ARC-MOF database that contains 279,632 MOFs and over 40 million charges. This model, which we call MEPO-ML, predicts charges with a mean absolute error of 0.025e on our test set of over 27 K MOFs. Other ML models reported in the literature were also trained using the same dataset and descriptors, and MEPO-ML was shown to give the lowest errors. The gas adsorption properties evaluated using MEPO-ML charges are found to be in significantly better agreement with the reference DFT-derived charges compared to the empirical charges, for both polar and non-polar gases. Using only a single CPU core on our benchmark computer, MEPO-ML charges can be generated in less than two seconds on average (including all computations required to apply the model) for MOFs in the test set of 27 K MOFs.

10.
Artículo en Inglés | MEDLINE | ID: mdl-38978825

RESUMEN

Background: The American Optometric Association defines computer vision syndrome (CVS), also known as digital eye strain, as "a group of eye- and vision-related problems that result from prolonged computer, tablet, e-reader and cell phone use". We aimed to create a well-structured, valid, and reliable questionnaire to determine the prevalence of CVS, and to analyze the visual, ocular surface, and extraocular sequelae of CVS using a novel and smart self-assessment questionnaire. Methods: This multicenter, observational, cross-sectional, descriptive, survey-based, online study included 6853 complete online responses of medical students from 15 universities. All participants responded to the updated, online, fourth version of the CVS questionnaire (CVS-F4), which has high validity and reliability. CVS was diagnosed according to five basic diagnostic criteria (5DC) derived from the CVS-F4. Respondents who fulfilled the 5DC were considered CVS cases. The 5DC were then converted into a novel five-question self-assessment questionnaire designated as the CVS-Smart. Results: Of 10 000 invited medical students, 8006 responded to the CVS-F4 survey (80% response rate), while 6853 of the 8006 respondents provided complete online responses (85.6% completion rate). The overall CVS prevalence was 58.78% (n = 4028) among the study respondents; CVS prevalence was higher among women (65.87%) than among men (48.06%). Within the CVS group, the most common visual, ocular surface, and extraocular complaints were eye strain, dry eye, and neck/shoulder/back pain in 74.50% (n = 3001), 58.27% (n = 2347), and 80.52% (n = 3244) of CVS cases, respectively. Notably, 75.92% (3058/4028) of CVS cases were involved in the Mandated Computer System Use Program. Multivariate logistic regression analysis revealed that the two most statistically significant diagnostic criteria of the 5DC were ≥2 symptoms/attacks per month over the last 12 months (odds ratio [OR] = 204177.2; P <0.0001) and symptoms/attacks associated with screen use (OR = 16047.34; P <0.0001). The CVS-Smart demonstrated a Cronbach's alpha reliability coefficient of 0.860, Guttman split-half coefficient of 0.805, with perfect content and construct validity. A CVS-Smart score of 7-10 points indicated the presence of CVS. Conclusions: The visual, ocular surface, and extraocular diagnostic criteria for CVS constituted the basic components of CVS-Smart. CVS-Smart is a novel, valid, reliable, subjective instrument for determining CVS diagnosis and prevalence and may provide a tool for rapid periodic assessment and prognostication. Individuals with positive CVS-Smart results should consider modifying their lifestyles and screen styles and seeking the help of ophthalmologists and/or optometrists. Higher institutional authorities should consider revising the Mandated Computer System Use Program to avoid the long-term consequences of CVS among university students. Further research must compare CVS-Smart with other available metrics for CVS, such as the CVS questionnaire, to determine its test-retest reliability and to justify its widespread use.

11.
Clin Exp Hepatol ; 9(2): 129-137, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37502440

RESUMEN

Aim of the study: Hepatocellular carcinoma (HCC) prognosis heavily depends on early diagnosis. We aimed to determine the role of serum urothelial carcinoma-associated 1 (UCA1) and wd repeat containing antisense to TP53 (WRAP53) as diagnostic tools of HCC. Material and methods: A case-control study including 90 subjects (30 patients having HCC, 30 patients having liver cirrhosis without HCC and 30 healthy controls) was performed. In all participants, the serum levels of UCA1 and WRAP53 were assessed by quantitative real-time polymerase chain reaction together with serumαa-fetoprotein (AFP). Results: Serum levels of both UCA1 and WRAP53 were upregulated in patients with HCC being significantly higher than in patients with liver cirrhosis and healthy control (p < 0.001). They were also correlated with some clinicopathological characteristics of HCC. Using the receiver operating curve, both UCA1 and WRAP53 showed higher diagnostic performance for HCC (AUC = 0.9, 73.3% sensitivity, 100% specificity and AUC = 0.85, 63.3% sensitivity, 80% specificity respectively) and their combination with AFP resulted in improved sensitivity and specificity (AUC = 0.97, 90% sensitivity, 100% specificity). Conclusions: Serum UCA1 and WRAP53 have the potential to be used alone, or in combination or with AFP, as diagnostic non-invasive biomarkers for HCC with accepted sensitivity and specificity. This study has been registered in clinicaltrials.gov with clinical trial registration number NCT05088811.

12.
J Occup Environ Hyg ; 9(12): 733-42, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23113576

RESUMEN

The welding process yields a high concentration of nanoparticles loaded with hexavalent chromium (Cr(6+)), a known human carcinogen. Previous studies have demonstrated that using tetramethylsilane (TMS) as a shielding gas additive can significantly reduce the Cr(6+) concentration in welding fume particles. In this study, a novel insulated double shroud torch (IDST) was developed to further improve the reduction of airborne Cr(6+) concentration by separating the flows of the primary shielding gas and the TMS carrier gas. Welding fumes were collected from a welding chamber in the laboratory and from a fixed location near the welding arc in a welding facility. The Cr(6+) content was analyzed with ion chromatography and X-ray photoelectron spectroscopy (XPS). Results from the chamber sampling demonstrated that the addition of 3.2 ≈ 5.1% of TMS carrier gas to the primary shielding gas resulted in more than a 90% reduction of airborne Cr(6+) under all shielding gas flow rates. The XPS result confirmed complete elimination of Cr(6+) inside the amorphous silica shell. Adding 100 ≈ 1000 ppm of nitric oxide or carbon monoxide to the shielding gas could also reduce Cr(6+) concentrations up to 57% and 35%, respectively; however, these reducing agents created potential hazards from the release of unreacted agents. Results of the field test showed that the addition of 1.6% of TMS carrier gas to the primary shielding gas reduced Cr(6+) concentration to the limitation of detection (1.1 µg/m(3)). In a worst-case scenario, if TMS vapor leaked into the environment without decomposition and ventilation, the estimated TMS concentration in the condition of field sampling would be a maximum 5.7 ppm, still well below its flammability limit (1%). Based on a previously developed cost model, the use of TMS increases the general cost by 3.8%. No visual deterioration of weld quality caused by TMS was found, although further mechanical testing is necessary.


Asunto(s)
Carcinógenos Ambientales/análisis , Cromo/análisis , Nanopartículas del Metal/análisis , Exposición Profesional/análisis , Dióxido de Silicio/química , Soldadura/instrumentación , Monóxido de Carbono/química , Carcinógenos Ambientales/química , Cromatografía por Intercambio Iónico , Cromo/química , Humanos , Nanopartículas del Metal/química , Óxido Nítrico/química , Exposición Profesional/prevención & control , Equipos de Seguridad , Ventilación
13.
J Surg Case Rep ; 2022(1): rjab645, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35096373

RESUMEN

We report a case of a two month old baby who had presented with an acute abdomen. Intra operative necrosis of the abdominal esophagus to distal of ligamentum treitz was noted. He was subjected to palliative care and passed away on Day 8 post-surgery.

14.
Eye Brain ; 14: 115-126, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36193222

RESUMEN

Background: Ultrasonographic measurement of optic nerve sheath diameter is a simple, non-invasive, and reliable method of detecting elevated intracranial pressure (ICP) in critical patients. Optic nerve sheath communicates with the dura mater covering the brain and contains cerebrospinal fluid, allowing pressure transmission from the cranium. Therefore, changes in cerebrospinal fluid (CSF) pressure have been shown to produce changes in ONSD. Objective: This study aimed to assess the accuracy of optic nerve sheath diameter (ONSD) in diagnosis and follow-up patients with disturbed conscious levels compared with CT brain and fundus examination. Patients and Methods: One hundred forty-one participants were included in the study, classified into 76 cases admitted with disturbed conscious levels due to elevated ICP and 65 controls. All patients were subjected to CT brain and optic nerve US and fundus examination at the time of admission and follow-up after 48 h after proper management. Results: The current study showed that ONSD is significant in predicting elevated ICP at the cut-off point of average ONSD of 5.19 mm with 97% sensitivity and 98% specificity, and the area under the curve (AUC) was 0.996. The present study revealed a significant inverse correlation between ONSD and GCS in patients with increased ICP. Conclusion: Ultrasonic measurement of ONSD is a promising technique in diagnosing and following patients with disturbed conscious levels.

15.
Arch Virol ; 156(11): 2039-43, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21761169

RESUMEN

A full-length infectious cDNA clone of potato virus Y (PVY) was constructed based on an isolate of the PVY(NTN-NW) strain, SYR-II-2-8, which is able to cause potato tuber necrotic ringspot disease (PTNRD). Silent point mutations were introduced to modify sequences similar to the prokaryotic promoter elements detected at the 5' terminus of the P3 coding region of SYR-II-2-8. This, along with modification of the growing conditions of E. coli, led to the successful construction of a stable full-length infectious cDNA clone, named p2-8C3. The biological properties of p2-8C3 were identical to those of SYR-II-2-8, both of which induced PTNRD in potato, veinal necrosis in tobacco, and similar symptoms in the potato cultivars inoculated.


Asunto(s)
ADN Complementario/genética , Enfermedades de las Plantas/virología , Potyvirus/genética , Potyvirus/aislamiento & purificación , Solanum tuberosum/virología , Secuencia de Aminoácidos , Secuencia de Bases , ADN Complementario/metabolismo , ADN Viral/genética , ADN Viral/metabolismo , Datos de Secuencia Molecular , Mutación , Potyvirus/clasificación , Potyvirus/fisiología , Nicotiana/virología
16.
Artículo en Inglés | MEDLINE | ID: mdl-18952688

RESUMEN

Weighlevel, a mixture of extract of four plants used in traditional Arabic and Islamic medicine as well as in European herbal medicine, was prepared and assessed for its safety and efficacy in weight loss. Leaves of Alchemilla vulgaris, Olea europaea and Mentha longifolia L., as well as seeds of Cuminum cyminum, were used. Cultured human fibroblasts treated with Weighlevel did not exhibit any sign of toxicity as evidenced by lactate dehydrogenase release. These results were confirmed in experimental studies on rats where an LD(50) of 15.3 g kg(-1) was observed. Significant antioxidant properties were seen at very low concentrations of Weighlevel (10 µg ml(-1)) as measured by the lipid peroxidation method. Progressive and significant weight loss was observed in chickens given this mixture weekly for 4 weeks compared with controls. Furthermore, a 3-fold increase in the thermogenesis was seen in rat interscapular brown adipose tissue following exposure to different concentrations of Weighlevel extract as determined by measurement of increased oxygen consumption. In addition, a clinical study was carried out among 80 human volunteers with a body mass index (BMI) of 30.67 ± 2.14 kg m(-2). All 80 subjects were asked to continue their usual diet but to eat only three main meals daily and to take one Weighlevel tablet 30 min before each meal. Fourteen subjects were excluded for not following the protocol, and 66 subjects were all evaluated for efficacy and tolerability of Weighlevel monthly for 3 months. Weighlevel was well tolerated by all subjects, and no side effects were reported. A progressive and significant weight loss was seen in these subjects during the whole study period. Higher levels of weight loss were seen in people with BMI of 25-30 kg m(-2) (overweight) compared to people with BMI >30 kg m(-2) (obese). The BMI was reduced after 3 months from 28.5 ± 1.2 and 32.1 ± 1.8 kg m(-2) to 24.5 ± 1.4 and 27.5 ± 2.2 kg m(-2) in overweight and obese group, respectively. Results indicate safety, tolerability and efficacy of Weighlevel.

17.
Artículo en Inglés | MEDLINE | ID: mdl-18955363

RESUMEN

Based on knowledge from traditional Arab herbal medicine, this in vitro study aims to examine the anti-inflammatory mechanism of Hypericum triquetrifolium by measuring the expression and release of pro-inflammatory cytokines, tumor necrosis factor-α (TNF-α) and interleukine-6 (IL-6), and inducible nitric oxide synthase (iNOS) in human monocytic cells, THP-1. The effects were assessed by measuring the levels of secretory proteins and mRNA of TNF-α and IL-6, the levels of nitric oxide (NO) secretion and the expression of iNOS in THP-1 cells. Cells were treated with 5 µg lipopolysaccharide/ml (LPS) in the presence and absence of increasing concentrations of extracts from the aerial parts of H. triquetrifolium. During the entire experimental period, we used extract concentrations (up to 250 µg mL(-1)) that had no cytotoxic effects, as measured with MTT and LDH assays. Hypericum triquetrifolium extracts remarkably suppressed the LPS-induced NO release, significantly attenuated the LPS-induced transcription of iNOS and inhibited in a dose-dependent manner the expression and release of TNF-α. No significant effects were observed on the release of IL-6. Taken together, these results suggest that H. triquetrifolium probably exerts anti-inflammatory effects through the suppression of TNF-α and iNOS expressions.

18.
J Ophthalmol ; 2021: 6630286, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33868724

RESUMEN

PURPOSE: To assess the visual, ocular, extraocular, and multifocal electroretinography (mfERG) outcomes of computer vision syndrome (CVS) among medical students. METHODS: This study was designed as a cross-sectional case-control study that included 733 medical students. All students completed a specially designed and validated CVS questionnaire survey (CVS-F3). Students from the control (No-CVS) and CVS groups underwent comprehensive ophthalmic examinations including the mfERG examinations. Our main outcome measures included uncorrected and corrected distance visual acuity (UDVA and CDVA, resp.) measurements, subjective and cycloplegic refractions, slit-lamp examination, intraocular pressure measurement, pupillary reflexes tests, ocular movements' tests, dry eye disease tests, and fundus and mfERG examinations. RESULTS: The CVS-F3 identified that 87.9% of students had complaints that might be related to CVS. We documented a 76% prevalence rate in students undergoing an ophthalmologic exam. The most common ocular and extraocular complaints included visual blur and headache (40.9% and 46.8%, resp.). Statistical logistic and linear regression analyses showed that refractive errors, prolonged screen-hours, close eye-screen distance, improper gaze angle, poor screen-resolution, and screen-glare were risk factors for developing CVS and influencing its severity. In the mfERG subgroup, 42.5% demonstrated reduced amplitudes of mfERG rings and quadrants, indicating reduced foveal responses. CONCLUSION: Surveys cannot yield an accurate CVS prevalence. However, they help to identify subjects at risk who should be comprehensively assessed to confirm or exclude CVS diagnosis. Smartphone misuse primarily caused CVS among users. Our mfERG findings might be a sign of potential CVS visual sequelae; however, future studies are warranted. Clinicians need to understand these sequelae to appropriately identify and treat CVS.

19.
Evid Based Complement Alternat Med ; 7(4): 419-24, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18955344

RESUMEN

Complementary medicine is a formal method of health care in most countries of the ancient world. It is expected to become more widely integrated into the modern medical system, including the medical curriculum. Despite the perception of modern medicine as more efficacious, traditional medicine continues to be practiced. More than 70% of the developing world's population still depends primarily on the complementary and alternative systems of medicine (CAM). In rural areas, cultural beliefs and practices often lead to self-care, home remedies or consultation with traditional healers. Herbal medicine can be broadly classified into four basic systems as follows: Traditional Chinese Herbalism, Ayurvedic Herbalism, Western Herbalism-which originally came from Greece and Rome to Europe and then spread to North and South America and Traditional Arabic and Islamic Medicine (TAIM). There is no doubt that today the concept of Arabic traditional herbal medicine is a part of modern life in the Middle East, and it is acquiring worldwide respect, with growing interest among traditional herbalists and the scientific community. TAIM therapies have shown remarkable success in healing acute as well as chronic diseases and have been utilized by people in most countries of the Mediterranean who have faith in spiritual healers. TAIM is the first choice for many in dealing with ailments such as infertility, epilepsy, psychosomatic troubles and depression. In parallel, issues of efficacy and safety of complementary medicine have become increasingly important and supervision of the techniques and procedures used is required for commercial as well as traditional uses. More research is therefore needed to understand this type of medicine and ensure its safe usage. The present review will discuss the status of traditional Arab medicine (particularly herbal medicine), including the efficacy and toxicity of specific medicinal preparations, with an emphasis on the modern in vitro and in vivo techniques.

20.
Clin Ophthalmol ; 14: 3495-3498, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33149542

RESUMEN

PURPOSE: To evaluate the safety and efficacy of topical difluprednate ophthalmic emulsion use for prophylaxis of corneal graft rejection in patients undergoing penetrating keratoplasty. METHODS: This study reviewed the charts of patients undergoing penetrating keratoplasty who were treated with difluprednate (DP) ophthalmic emulsion postoperatively. At each follow-up visit, patients were followed for signs of graft rejection, cataract development, and intraocular pressure rise in addition to routine ocular examination. RESULTS: The charts of 36 patients (38 eyes) who underwent penetrating keratoplasty (PKP) (27 eyes) and PKP triple (11 eyes) were reviewed. All eyes were followed up for at least 8 months postoperatively. Five grafts developed rejection and three grafts subsequently failed. Six eyes had an increase of IOP that required use of antiglaucoma drops. Three eyes were switched from difluprednate to prednisolone acetate (PA) after persistent rise of IOP failed to respond to antiglaucoma drops. None of these cases needed glaucoma surgery. Two patients developed cataract during the follow-up period (out of 12 phakic eyes). CONCLUSION: Topical difluprednate is potentially effective and safe in preventing graft rejection after penetrating keratoplasty. Larger prospective clinical trials are warranted.

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