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1.
J Hand Surg Am ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39115486

RESUMEN

PURPOSE: Wide awake local anesthesia no tourniquet (WALANT) is gaining popularity with flexor tendon repair. We hypothesized that results of zone II flexor tendon repair performed under WALANT would be superior to those performed under general anesthesia (GA). METHODS: A randomized controlled trial was conducted to compare results of repair of zone II flexor tendon lacerations under WALANT versus GA. Following sample size estimation, 86 digits were included and randomized into two groups. All surgeries were performed by a single surgeon using a six-stranded core stitch and running epitenon suture. All patients followed the same early active rehabilitation protocol. The primary outcome was recovery calculated using the Strickland and Glogovac criteria. Secondary outcomes included rupture rate, complication rate, and Disabilities of the Arm, Shoulder, and Hand (DASH) score. All outcomes were reported at the 6-month visit for all patients. RESULTS: Of the 86 digits, three were lost to follow-up. Analysis was performed on 43 digits in the WALANT group and 40 in the GA group. Demographic characteristics including age and sex were comparable in both groups. Rupture of the repair occurred in two digits in each of the WALANT and GA groups. An excellent or good outcome was achieved in 49% and 56% of the digits in the WALANT and GA groups, respectively. This difference was not statistically significant. DASH scores averaged 12.9 and 8.4 for the WALANT and GA groups, respectively. CONCLUSIONS: WALANT may not be superior to GA in regards function, rates of rupture, and patient-reported outcomes in repair of zone II flexor tendon lacerations. Surgeons can be confident in choosing either technique if rigorous patient selection, sound surgical technique, and proper hand therapy are employed. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic I.

2.
BMC Med Genomics ; 17(1): 202, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39123171

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is the most common primary liver cancer. Chronic hepatitis and liver cirrhosis lead to accumulation of genetic alterations driving HCC pathogenesis. This study is designed to explore genomic landscape of HCC in Egyptian patients by whole exome sequencing. METHODS: Whole exome sequencing using Ion Torrent was done on 13 HCC patients, who underwent surgical intervention (7 patients underwent living donor liver transplantation (LDLT) and 6 patients had surgical resection}. RESULTS: Mutational signature was mostly S1, S5, S6, and S12 in HCC. Analysis of highly mutated genes in both HCC and Non-HCC revealed the presence of highly mutated genes in HCC (AHNAK2, MUC6, MUC16, TTN, ZNF17, FLG, MUC12, OBSCN, PDE4DIP, MUC5b, and HYDIN). Among the 26 significantly mutated HCC genes-identified across 10 genome sequencing studies-in addition to TCGA, APOB and RP1L1 showed the highest number of mutations in both HCC and Non-HCC tissues. Tier 1, Tier 2 variants in TCGA SMGs in HCC and Non-HCC (TP53, PIK3CA, CDKN2A, and BAP1). Cancer Genome Landscape analysis revealed Tier 1 and Tier 2 variants in HCC (MSH2) and in Non-HCC (KMT2D and ATM). For KEGG analysis, the significantly annotated clusters in HCC were Notch signaling, Wnt signaling, PI3K-AKT pathway, Hippo signaling, Apelin signaling, Hedgehog (Hh) signaling, and MAPK signaling, in addition to ECM-receptor interaction, focal adhesion, and calcium signaling. Tier 1 and Tier 2 variants KIT, KMT2D, NOTCH1, KMT2C, PIK3CA, KIT, SMARCA4, ATM, PTEN, MSH2, and PTCH1 were low frequency variants in both HCC and Non-HCC. CONCLUSION: Our results are in accordance with previous studies in HCC regarding highly mutated genes, TCGA and specifically enriched pathways in HCC. Analysis for clinical interpretation of variants revealed the presence of Tier 1 and Tier 2 variants that represent potential clinically actionable targets. The use of sequencing techniques to detect structural variants and novel techniques as single cell sequencing together with multiomics transcriptomics, metagenomics will integrate the molecular pathogenesis of HCC in Egyptian patients.


Asunto(s)
Carcinoma Hepatocelular , Secuenciación del Exoma , Neoplasias Hepáticas , Mutación , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Masculino , Egipto , Persona de Mediana Edad , Femenino , Genómica , Adulto
3.
Technol Cancer Res Treat ; 22: 15330338231206335, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37908130

RESUMEN

External beam radiation therapy (EBRT) has increasingly been utilized in the treatment of hepatocellular carcinoma (HCC) due to technological advances with positive clinical outcomes. Innovations in EBRT include improved image guidance, motion management, treatment planning, and highly conformal techniques such as intensity-modulated radiation therapy (IMRT) and stereotactic body radiation therapy (SBRT). Moreover, proton beam therapy (PBT) and magnetic resonance image-guided radiation therapy (MRgRT) have expanded the capabilities of EBRT. PBT offers the advantage of minimizing low- and moderate-dose radiation to the surrounding normal tissue, thereby preserving uninvolved liver and allowing for dose escalation. MRgRT provides the advantage of improved soft tissue delineation compared to computerized tomography (CT) guidance. Additionally, MRgRT with online adaptive therapy is particularly useful for addressing motion not otherwise managed and reducing high-dose radiation to the normal tissue such as the stomach and bowel. PBT and online adaptive MRgRT are emerging technological advancements in EBRT that may provide a significant clinical benefit for patients with HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Terapia de Protones , Radioterapia Guiada por Imagen , Humanos , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/radioterapia , Radioterapia Guiada por Imagen/métodos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/radioterapia , Planificación de la Radioterapia Asistida por Computador/métodos , Espectroscopía de Resonancia Magnética
4.
BMC Med Genomics ; 16(1): 89, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-37127645

RESUMEN

Inherited retinal dystrophies (IRDs) are a major cause of vision loss. Altogether are highly heterogeneous genotypically and phenotypically, exhibiting substantial differences worldwide. To shed more light on these conditions, we investigated the genetic and phenotypic landscape of IRDs in the Arabs globally and per country.We analyzed 1,621 affected individuals from 16 Arabic countries reported in 198 articles. At the phenotypic level, rod-cone dystrophy (RCD) and Usher syndrome were the most prevalent conditions among non-syndromic and syndromic IRDs. At the gene level, TULP1, ABCA4, RP1, CRB1, MYO7A, RPE65, KCNV2, and IMPG2 were the most mutated genes. Interestingly, all except CRB1 were highly prevalent because they harbored founder mutations, implying that consanguinity is a major determinant in Arab countries. Of note, ~ 93% of the investigated individuals carried homozygous mutations. The country analysis for the IRDs conditions and their associated genotypes revealed that whereas Leber Congenital Amaurosis, RCD, and USHER syndrome were widely distributed, bestrophinopathies and non-syndromic hearing loss were restricted to specific countries (till now).This study could be a starting point for initiating suitable health policies towards IRDs in the Arab world. The high degree of homozygosity urges the need for genetic counsellors to provide personalized information and support the affected individuals.


Asunto(s)
Amaurosis Congénita de Leber , Canales de Potasio con Entrada de Voltaje , Distrofias Retinianas , Síndromes de Usher , Humanos , Árabes , Distrofias Retinianas/genética , Amaurosis Congénita de Leber/genética , Mutación , Transportadoras de Casetes de Unión a ATP/genética , Proteínas del Ojo/genética , Proteínas de la Membrana/genética , Proteínas del Tejido Nervioso/genética , Canales de Potasio con Entrada de Voltaje/genética
5.
Life (Basel) ; 12(11)2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36362916

RESUMEN

Herein, two seaweed extracts (Sargassum latifolium and Corallina elongate), and two commercial seaweed products (Canada power and Oligo-X) with a concentration of 5% were used to alleviate the drought stress on wheat plants. The extract of C. elongate had the highest capacity to ameliorate the deleterious effects of water scarcity followed by S. latifolium and the commercial products. The drought stress reduced wheat shoots length and the contents of pigments (chlorophyll and carotenoids), carbohydrates, and proteins. While the highest increment in the total carbohydrates and protein contents of the wheat shoot after two stages, 37-and 67-days-old, were noted in drought-stressed plants treated with C. elongate extract with values of (34.6% and 22.8%) and (51.9% and 39.5%), respectively, compared to unstressed plants. Decreasing the activity of antioxidant enzymes, peroxidase, superoxidase dismutase, and polyphenol oxidase in drought-stressed plants treated with algal extracts indicated amelioration of the response actions. Analysis of phytohormones in wheat plants exhibited increasing GA3 and IAA contents with percentages of (20.3-13.8%) and (72.7-25%), respectively. Interestingly, all morphological and metabolic characteristics of yield were improved due to the algal treatments compared with untreated drought-stressed plants. Overall, the algal extracts, especially those from seaweed of C. elongate, could represent a sustainable candidate to overcome the damage effects of water deficiency in the wheat plant.

6.
Saudi J Biol Sci ; 29(6): 103273, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35431593

RESUMEN

Chronic diseases including cardiovascular, diabetes and cancer persist for a long time in the course of treatment affecting health and are currently the cause of many deaths. In most cases, the treatment of chronic infectious diseases especially Tuberculosis relies on conventional drugs which are currently becoming fruitless due to drug resistance and unpredicted complications in course of treatment. However, herbal medicines have for a long time been used in prevention and treatment of chronic diseases including asthma and heart diseases in Africa. In this study, we extracted metabolites and screened for active compounds with potential free radical scavenging and pharmacological activities from Bersama abyssinica, the plant commonly used in traditional medicine in Tanzania. B. abyssinica root, stembark and leaf were air dried, sequentially extracted in various solvents including petroleum ether, dichloromethane, ethylacetate and methanol to yield extracts and fractions. The extracts and fractions were tested for the presence of several metabolites and antioxidant activity. The analysis of chemical compounds from resultant extracts was done by GC-MS for non-polar factions and LC-MS/MC for moderate polar extracts.High amount of phenolic acid, flavonoids and tannin were identified in ethylacetate fraction compared to ethanol, dichloromethane and petroleum ether. The GC-MS analysis of petroleum ether extract of B. abyssinica stem back yielded twelve (12) compounds with varying composition. The most abundant compounds were 2-Butenoic acid, 3-methyl-, ethyl ester comprising 33.8%, n-Hexadecanoic acid comprising 16.7% and Ethanolpentamethyl- yielded in 16.7%.The LC-MS/MS analysis of Ethyl acetate fractions yielded 20 compounds including; Mangiferin and Isoquercitin were abundant in leaves, stembark and roots. Lastly, ethyl vanillate was identified in both roots and leaves whereas Quercitrin and 7,8-Dimethoxycoumarin were found in stembark and root.These findings indicated that B. abyssinica is rich in phenolic compounds ranging from phenolic acids, flavonoids and coumarin that possess high antioxidant and pharmacological properties potential for treatment of chronic diseases.

7.
Front Biosci (Landmark Ed) ; 27(1): 27, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-35090332

RESUMEN

BACKGROUND AND OBJECTIVES: Vascular Endothelial Growth Factor (VEGF) is an essential regulator of vascular biology. In addition to the well-established role in angiogenesis, circulating VEGF levels were found elevated in severely anemic patients, pointing out that anemia might affect the progression of angiogenesis in malignant and benign diseases through the alteration of VEGF levels. Ten single nucleotide polymorphisms (SNPs) in VEGFA and other loci were shown to explain more than 50% of its circulating levels. This study investigated the association of those ten VEGF-related SNPs with serum iron levels in a general Lebanese population free of chronic diseases (N = 460). RESULT: We found that the rs10738760 and the body mass index (BMI) were associated with decreased Iron levels (p = 0.002, and p < 0.001, respectively). When taken together, both variables, rs10738760 and BMI, interacted to reduce iron levels (p < 0.001). According to obesity status, the stratification revealed that the effect of rs10738760 was more pronounced in obese than non-obese individuals (p = 0.025). Conclusion: The intergenic SNP rs10738760 is associated with circulating iron levels, and this association depends on BMI status. Although of interest, these results need replication in larger populations from different ancestries.


Asunto(s)
Polimorfismo de Nucleótido Simple , Factor A de Crecimiento Endotelial Vascular/genética , Índice de Masa Corporal , Genotipo , Humanos , Hierro , Factores de Crecimiento Endotelial Vascular
8.
AAPS J ; 22(2): 51, 2020 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-32086622

RESUMEN

The orally available novel small molecule SHetA2 is the lead sulfur-containing heteroarotinoid that selectively inhibits cancer cells over normal cells, and is currently under clinical development for anticancer treatment and cancer prevention. The objective of this study was to assess and characterize the tissue distribution of SHetA2 in tumor-bearing mice by developing a physiologically based pharmacokinetic (PBPK) model. An orthotopic SKOV3 ovarian cancer xenograft mouse model was used to most accurately mimic the ovarian cancer tumor microenvironment in the peritoneal cavity. SHetA2 concentrations in plasma and 14 different tissues were measured at various time points after a single intravenous dose of 10 mg/kg and oral dose of 60 mg/kg, and these data were used to develop a whole-body PBPK model. SHetA2 exhibited a multi-exponential plasma concentration decline with an elimination half-life of 4.5 h. Rapid and extensive tissue distribution, which was best described by a perfusion rate-limited model, was observed with the tissue-to-plasma partition coefficients (kp = 1.4-21.2). The PBPK modeling estimated the systemic clearance (76.4 mL/h) from circulation as a main elimination pathway of SHetA2. It also indicated that the amount absorbed into intestine was the major determining factor for the oral bioavailability (22.3%), while the first-pass loss from liver and intestine contributed minimally (< 1%). Our results provide an insight into SHetA2 tissue distribution characteristics. The developed PBPK model can be used to predict the drug exposure at tumors or local sites of action for different dosing regimens and scaled up to humans to correlate with efficacy.


Asunto(s)
Antineoplásicos/farmacocinética , Cromanos/farmacocinética , Modelos Biológicos , Neoplasias Ováricas/tratamiento farmacológico , Tionas/farmacocinética , Administración Intravenosa , Administración Oral , Animales , Antineoplásicos/administración & dosificación , Disponibilidad Biológica , Línea Celular Tumoral , Cromanos/administración & dosificación , Femenino , Humanos , Ratones Desnudos , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Tionas/administración & dosificación , Distribución Tisular , Ensayos Antitumor por Modelo de Xenoinjerto
9.
Eur J Gastroenterol Hepatol ; 31(4): 418-424, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30694909

RESUMEN

Endoscopic submucosal dissection (ESD) and gastrectomy with lymph node dissection are considered acceptable treatment modalities for early gastric cancer (EGC). In the last decade, ESD has become more favorable than surgery as it offers faster recovery, lower costs, and a superior quality of life when compared to gastrectomy. The aim of this study is to compare the long-term outcome of ESD versus surgery in EGC. We performed a systematic and comprehensive search of major reference databases (Medline, Embase, CINHAL) for all studies that compared the outcome of EGC for patients underwent ESD or surgery in the same cohort. A systematic review was conducted through November 2017, using pooled analysis to calculate 5-year overall survival (OS) rate, disease-specific survival (DSS) rate, disease-free survival (DFS) rate, and recurrence-free survival (RFS) rate of ESD versus gastrectomy. Five-year OS and DSS were similar between ESD and gastrectomy groups 96 versus 96% and 99.4 versus 99.2%, respectively. Likewise, DFS was similar in both groups 95.9 versus 98.5% odds ratio 1.86 (0.57-6.0) P=0.3. However, ESD had a lower RFS compared to surgery 92.4 versus 98.3% odds ratio 0.17 (0.1-4.9) P=0.001. Overall, there was a higher recurrence rate in patients who underwent ESD compared to surgery [40/2943 (1.4%) vs. 12/3116 (0.4) risk ratio (RR) 2.5 (1.3-4.8) P=0.005]. Moreover, synchronous and metachronous cancers were more prevalent in the ESD group compared to the surgery group [1.5 vs. 0.1% RR 5.7 (1.5-21.9) P=0.01] [16/1082 (1.5%) vs. 1/1485 (0.1%) RR 10.1 (5.9-17.1) P=0.0001]. Five-year OS, DSS and DFS were similar between ESD and surgery groups. However, recurrent, synchronous and metachronous cancers were more prevalent in patients treated by ESD compared to patients treated by surgery, resulting in a lower RFS. Adequate surveillance with upper endoscopy is crucial after ESD to detect early recurrence and metachronous lesions.


Asunto(s)
Resección Endoscópica de la Mucosa/métodos , Gastrectomía/métodos , Neoplasias Gástricas/cirugía , Resección Endoscópica de la Mucosa/efectos adversos , Gastrectomía/efectos adversos , Humanos , Recurrencia Local de Neoplasia , Neoplasias Primarias Secundarias , Tasa de Supervivencia , Resultado del Tratamiento
10.
AAPS PharmSciTech ; 20(1): 20, 2019 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-30604109

RESUMEN

SHetA2 is a novel anticancer drug with poor aqueous solubility. In formal toxicological studies, Kolliphor HS 15 was used as a solubilizing agent to increase the oral bioavailability of SHetA2. The purpose of this study was to formulate SHetA2 and Kolliphor HS 15 as solid powders to facilitate their filling in hard gelatin capsules for clinical trials. Two manufacturing processes, ultra-rapid freeze-drying (URFD) and spray freeze drying (SFD), were employed to fabricate solid powders of SHetA2-Kolliphor HS 15 and trehalose. The morphology, size, flowability, and compressibility of URFD-SHetA2 and SFD-SHetA2 powders were characterized. The crystallinity and apparent maximum solubility of SHetA2 in both powders were also determined. SFD-SHetA2 powders were spherical in shape, small, and with a wide size distribution while the URFD-SHetA2 powders were irregularly shaped and big but with a narrower distribution. DSC and XRD analyses indicated that SHetA2 was mostly amorphous in both powders. The flow of both powders was categorized as "good" (angle of repose < 35°). The uniformity of drug content in URFD-SHetA2 powders was more variable than that in SFD-SHetA2 powders. The solubility profile of SHetA2 in both powders SGF exhibited a transient supersaturation "spring effect" due to the drug's amorphousness followed by extended supersaturation "parachute effect" at approximately 6 µg/ml for both powders compared to 0.02 ± 0.01 µg/ml for unprocessed drug. In conclusion, both URFD and SFD formed solid SHetA2 Kolliphor powders that are possible formulation candidates to be filled in hard gelatin capsules for clinical trials.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacocinética , Cromanos/síntesis química , Cromanos/farmacocinética , Tionas/síntesis química , Tionas/farmacocinética , Administración Oral , Antineoplásicos/administración & dosificación , Disponibilidad Biológica , Cromanos/administración & dosificación , Desecación , Liofilización/métodos , Ácido Gástrico/metabolismo , Humanos , Tamaño de la Partícula , Polvos , Solubilidad , Tionas/administración & dosificación , Difracción de Rayos X
11.
Mol Pharm ; 15(1): 300-313, 2018 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-29219321

RESUMEN

Tuberculosis (TB) is a life threatening pulmonary infection caused by Mycobacterium tuberculosis (MTB). Current treatments are complex, lengthy, and associated with severe side effects that decrease patient compliance and increase the probability of the emergence of drug resistant strains. Thus, more effective drugs with little to no side effects are needed to diversify the armamentarium against the global TB epidemic. SHetA2, an anticancer compound with null toxicity at doses much higher than the effective dose, was recently discovered to be active against MTB. In the present study, a dry powder formulation of SHetA2 for pulmonary delivery was developed to overcome its poor aqueous solubility and to maximize its concentration in the lungs, the main site of TB infection. Using quality by design (QbD) methodology, three different formulations of SHetA2 microparticles (MPs) were designed, manufactured, and optimized, SHetA2 alone, SHetA2 PLGA, and SHetA2 mannitol MPs, to maximize the drug dose, target alveolar macrophages, and increase drug solubility, respectively. The resulting three SHetA2 MP formulations had spherical shape with particle size ranging from 1 to 3 µm and a narrow size distribution, suitable for uniform delivery to the alveolar region of the lungs. Upon dispersion with the Aerolizer dry powder inhaler (DPI), all three SHetA2 MP formulations had aerodynamic diameters smaller than 3.3 µm and fine particle fractions (FPF4.46) greater than 77%. SHetA2 remained chemically stable after MP manufacture by spray drying, but the drug transformed from the crystalline to the amorphous form, which significantly enhanced the solubility of SHetA2. Using a custom-made dissolution apparatus, the FPF4.46 of SHetA2 MP dissolved much faster and to a greater extent (21.19 ± 4.40%) than the unprocessed drug (3.51 ± 0.9%). Thus, the physicochemical characteristics, in vitro aerosol performance, and dissolution rate of the optimized SHetA2 MPs appear to be suitable to achieve therapeutic concentrations in the lungs.


Asunto(s)
Aerosoles/química , Cromanos/química , Cromanos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Tionas/química , Tionas/farmacología , Pulmón/metabolismo , Pulmón/microbiología , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
12.
J Mol Recognit ; 30(2)2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27774692

RESUMEN

Three isolectins denoted hereforth MBaL-30, MBaL-60, and MBaL-80 were isolated from seeds extract of Momordica balsamina by 30%, 60%, and 80% ammonium sulfate saturations, respectively. The native molecular weights of these lectins, as judged by gel filtration, were 108, 56, and 160 kDa, respectively. On SDS-PAGE, under reduced condition, 27 kDa band was obtained for all isolectins. The lectins hemagglutinating activities were variably inhibited by d-galactose (minimum inhibitory concentrations = 12.5mM, 50mM, and 0.391mM, respectively). MBaL-30 and -60 could agglutinate all human blood types with slight preference for the A and O blood groups, whereas MBaL-80 did not agglutinate B and AB blood types. The 3 isolectins were purified from crude seeds extract, collectively, in a single step on the affinity matrix Lactamyl-Seralose 4B; this purified lectin fraction, which contains all isolectins, is termed MBaL. The N-terminal of MBaL till the 25th amino acid was NLSLSELDFSADTYKSFIKNLRKQL, which shares 88% sequence identity with Momordica charantia lectin type-2 ribosomal inactivating protein from Momordica charantia and 50% with momordin II from Momordica balsamina. MBaL retained 100% activity at up to 50°C for 30 minutes. MBaL-30 and MBaL-60 exhibited maximum activities in the pH range between 4 and 8, while MBaL-80 was showing maximum activity in the pH range between 3 and 5. Treatment of MBaL-30 and MBaL-60 with EDTA completely abolished their hemagglutinating activities. Addition of Zn and Fe ions to the ethylenediaminetetraacetic acid-treated MBaL-30 and MBaL-60 lectins did not only regained the loss of activity but also resulted in 200% to 300% increase in activity, respectively. MBaL-30 and -60 agglutinated gram positive Listeria monocytogenes and Staphylococcus aureus, whereas MBaL-30 could merely agglutinate Escherichia coli. None of these lectins could arrest bacterial growth. Addition of MBaL to cancer cell lines (Gastric cancer cell line (AGS) and Gastric cencer cell line (MKN45), Glioblastoma (ECV-304), and Human urinary bladder cancer cell line (U87-MG)) at varying concentrations did not cause statistically significant changes on cell growth and viability.


Asunto(s)
Momordica/metabolismo , Lectinas de Plantas/análisis , Semillas/metabolismo , Secuencia de Aminoácidos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Galactosa/metabolismo , Pruebas de Hemaglutinación , Humanos , Peso Molecular , Lectinas de Plantas/química , Lectinas de Plantas/metabolismo
13.
Clin Exp Pharmacol Physiol ; 38(12): 791-5, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21913957

RESUMEN

1. The ratio of nitric oxide (NO) to free radicals is critical during skeletal muscle contraction. Changes in this ratio have been suggested to play a role in muscle fatigue. 2. The aim of the present study was to investigate the changes in NO and free radicals during tetanic and subtetanic contraction and fatigue in the gastrocnemius muscle of adult male Wistar rats. 3. Rats were subjected to either low- or high-frequency stimulation (10 and 100 Hz, respectively) of the right gastrocnemius muscle. Both groups were further subdivided into untreated (0.9% NaCl solution), N(G) -nitro-L-arginine methyl ester (L-NAME)-treated and reduced glutathione (GSH)-treated groups. Rats were administered their treatments intraperitoneally 30 min prior to electrical stimulation. 4. Levels of both NO and lipid peroxides increased significantly during peak force contraction for either type of contractions, with a more significant response during subtetanic contraction. Treatment with L-NAME significantly reduced the maximal force and this effect was more marked in the low frequency-stimulated group. Although peroxides levels were reduced by GSH, it had no significant effect on force production. In L-NAME-treated rats, the onset of 50% fatigue was accelerated with a significant increase in peroxides levels, whereas the opposite effects were observed after GSH treatment. 5. Current results reflect the importance of endogenous NO, as an anti-oxidant, in aiding muscle performance by overcoming oxidative stress during fatigue. They provide a possible explanation as to why patients with myopathies like Duchenne muscular dystrophy, in which dystrophin is lacking suffer from muscle weakness and fatigue easily.


Asunto(s)
Radicales Libres/metabolismo , Contracción Muscular/fisiología , Fatiga Muscular/fisiología , Músculo Esquelético/fisiología , Óxido Nítrico/metabolismo , Animales , Estimulación Eléctrica , Inhibidores Enzimáticos/farmacología , Radicales Libres/análisis , Glutatión/metabolismo , Peróxidos Lipídicos , Masculino , Contracción Muscular/efectos de los fármacos , Fatiga Muscular/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico/análisis , Ratas , Ratas Wistar
14.
Microbiology (Reading) ; 153(Pt 11): 3631-3644, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17975071

RESUMEN

Identification of short genes that encode peptides of fewer than 60 aa is challenging, both experimentally and in silico. As a consequence, the universe of these short coding sequences (CDSs) remains largely unknown, although some are acknowledged to play important roles in cell-cell communication, particularly in Gram-positive bacteria. This paper reports a thorough search for short CDSs across streptococcal genomes. Our bioinformatic approach relied on a combination of advanced intrinsic and extrinsic methods. In the first step, intrinsic sequence information (nucleotide composition and presence of RBSs) served to identify new short putative CDSs (spCDSs) and to eliminate the differences between annotation policies. In the second step, pseudogene fragments and false predictions were filtered out. The last step consisted of screening the remaining spCDSs for lines of extrinsic evidence involving sequence and gene-context comparisons. A total of 789 spCDSs across 20 complete genomes (19 Streptococcus and one Enterococcus) received the support of at least one line of extrinsic evidence, which corresponds to an average of 20 short CDSs per million base pairs. Most of these had no known function, and a significant fraction (31%) are not even annotated as hypothetical genes in GenBank records. As an illustration of the value of this list, we describe a new family of CDSs, encoding very short hydrophobic peptides (20-23 aa) situated just upstream of some of the positive transcriptional regulators of the Rgg family. The expression of seven other short CDSs from Streptococcus thermophilus CNRZ1066 that encode peptides ranging in length from 41 to 56 aa was confirmed by real-time quantitative RT-PCR and revealed a variety of expression patterns. Finally, one peptide from this list, encoded by a gene that is not annotated in GenBank, was identified in a cell-envelope-enriched fraction of S. thermophilus CNRZ1066.


Asunto(s)
Secuencia de Aminoácidos , Codón Iniciador , Biología Computacional/métodos , Genoma Bacteriano , Streptococcus/genética , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Enterococcus faecalis/genética , Regulación Bacteriana de la Expresión Génica , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Péptidos/química , Péptidos/genética , Filogenia , Streptococcus/crecimiento & desarrollo , Streptococcus thermophilus/genética , Streptococcus thermophilus/crecimiento & desarrollo , Transactivadores/química , Transactivadores/genética
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