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1.
Zhonghua Yi Xue Za Zhi ; 100(35): 2779-2784, 2020 Sep 22.
Artículo en Chino | MEDLINE | ID: mdl-32972060

RESUMEN

Objectives: To investigated whether berberine could ameliorate septic cardiomyopathy in a rat model of sepsis and it's mechanisms. Methods: SD rats were divided into 3 groups: sepsis group (LPS group), rats were intraperitoneal injected of LPS (10 mg/kg); Berberine intervention group (Ber group), Ber (50 mg/kg, one time per day) was gavage fed 3 days before intraperitoneally injection of lipopolysaccharides (LPS); control group (Con group), rats were gavage fed with double distilled water (2 ml/100 g, one time per day) 3 days before intraperitoneal injection of normal saline (1 ml/100 g). LPS group and the Ber group was further divided into 3 subgroups (n=6), and the follow-up experiments were conducted at 6 h, 24 h and 48 h after LPS injection (of which 48 h subgroup rats were gavage fed with Ber/saline at 24 h). Left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), and the maximum rate of change of left ventricular pressure (±dp/dtmax) were monitored, the level of cardiac troponin T (cTnT), tumor necrosis factor (TNF)-α and interleukin (IL)-1ß was detected by ELISA method, HE staining of myocardial tissues was done to observe myocardial injury; Western blotting method was used to detect the expression of toll-like receptor 4(TLR4) protein in rat myocardial tissue, the level of myocardial cell nucleus protein p65 was detected to reflects the degree of NF-κB activation. The correlation of factors was analyzed with Pearson correlation analysis. Results: Pre-treatment with berberine stabilized cardiac hemodynamics and improved the systolic function and diastolic function in the heart of LPS-induced rats, as evidenced by the partial recovery of the reduced±dp/dtmax and LVSP, as well as the decreased LVEDP. Compared with the LPS group, the Ber group showed improved myocardial injury, as demonstrated by decreased cTnT at each time point. HE staining results showed that berberine decreased inflammatory cell infiltration and LPS-induced cell swelling. These effects were observed early at 6 hours, severe at 24 hours, and become more serious at 48 hours after LPS injection. Further, TLR4 and NF-κB p65 subunits, which were the two key factors of the TLR4/NF-κB signaling, were upregulated in the LPS group and attenuated in the Ber group. Consistently, the expression levels of the downstream cytokines TNF-α and IL-1ß were lower in the Ber group than those in the LPS group (all P<0.05). Myocardial injury markers were positively correlated with the markers of TLR4/NF-κB signals and the downstream host inflammatory factors (all P<0.05). Conclusions: Berberine can improve myocardial injury and cardiac function in sepsis rats, the mechanism is considered to be related to that it can inhibit the activation of TLR4/NF-κB signaling pathway induced by LPS and further reducing the production of TNF-α and IL-1ß.


Asunto(s)
Berberina/uso terapéutico , Sepsis , Animales , Lipopolisacáridos , FN-kappa B , Ratas , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa
2.
Zhonghua Yi Xue Za Zhi ; 100(32): 2525-2531, 2020 Aug 25.
Artículo en Chino | MEDLINE | ID: mdl-32829600

RESUMEN

Objective: To systematically evaluate the efficacy and safety of vitamin D supplementation in the treatment of pulmonary tuberculosis. Methods: Biomedical Database was searched to collect randomized controlled trials (RCT) related to vitamin D supplementation in tuberculosis patients, and the retrieval time was from establishment to November 2019. Two evaluators independently screened the literature and extracted the data. The negative conversion rate of acid-fast-bacilli of sputum smear, the negative conversion rate of mycobacterium tuberculosis culture and the change of serum vitamin D level were the main outcome indicators, and the body mass index was the secondary outcome indicator. The incidence of hypercalcemia and abnormal urinary calcium were used as adverse event indicators and the RevMan 5.2 software was used for meta-analysis. Results: A total of 8 RCT(S) met the inclusion criteria, including 850 patients with tuberculosis. Meta-analysis showed that compared with the control group, negative conversion rate of acid-fast-bacilli of sputum smear and serum vitamin D level increased after 8 weeks of vitamin D supplementation [RR (95%CI) and mean deviation (MD) (95%CI) were 1.06 (1.00, 1.13) and 8.81 (1.81, 15.81), respectively; negative conversion rate of acid-fast-bacilli of sputum smear was not increased at week 4 and 12 [RR (95%CI) were 1.08 (0.97, 1.20) and 1.01 (0.91, 1.12), respectively]; negative conversion rate of mycobacterium tuberculosis culture in sputum was not increased after 4 and 8 weeks [RR (95%CI) were 1.06 (0.91, 1.22) and 1.02 (0.96, 1.08), respectively]; there was no change in body mass index [MD (95%CI):-0.02 (-0.53, 0.50)]; there was increased risk of abnormal urinary calcium [RR (95%CI): 2.45 (1.75, 3.41)], while no increase in risk of hypercalcemia [RR (95%CI): 1.99 (0.96, 4.13)]. Conclusion: Vitamin D supplementation is safe but not effective in the treatment of pulmonary tuberculosis.


Asunto(s)
Tuberculosis Pulmonar , Tuberculosis , Suplementos Dietéticos , Humanos , Esputo , Vitamina D
3.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 54(10): 656-661, 2019 Oct 09.
Artículo en Chino | MEDLINE | ID: mdl-31607000

RESUMEN

Objective: To evaluate the antiseptic effect of combined using of 5% sodium hypochlorite and calcium silicate-based root canal sealer against Enterococcus faecalis (Ef) biofilms in infected dentinal tubules in vitro. Methods: Cells of Ef were inoculated into the dentinal tubules of single-rooted teeth (without caries, periapical lesions and malformations extracted due to periodontal disease or orthodontic reasons; collected from Department of Maxillofacial Surgery, The First Affiliated Hospital of Zhengzhou University) with centrifugation and incubated in brain-heart infusion (BHI) to form 3-week-old biofilms. The infected samples were subjected to sodium hypochlorite or sterile water bathing for 10 minutes followed by calcium silicate-based root canal sealer (iRoot SP) (calcium silicate-based group), Gutta-percha group and sterile water group placed on the root canal wall for 1, 4 and 12 weeks. There were two samples in each treatment at each point. The antiseptic effectiveness of combined use of sodium hypochlorite and calcium silicate-based root canal sealer was analyzed by laser scanning confocal microscope (LSCM), ANOVA and LSD-t test. Results: After treatment with 5% sodium hypochlorite, in calcium silicate-based group for 4 and 12 weeks more Ef biofilm cells [(75.3±3.5)% and (74.8±3.8)%] were killed than in Gutta-percha group [(65.9±4.1)% and (63.0±3.7)%] and sterile water group [(63.9±4.0)% and (64.2±3.5)%] (P<0.05). After being treated with sterile water, the proportion of dead bacterial cells in calcium silicate-based group for 1, 4 and 12 weeks [(27.5±4.6)%, (43.0±4.4)% and (40.3±6.1)%] were more than those in Gutta-percha group and sterile water group (P<0.05). After being treated with 5% sodium hypochlorite or sterile water, more biofilm bacteria were killed in calcium silicate-based group for 4 and 12 weeks than in calcium silicate-based group for 1 week (P<0.05). Conclusions: The combined use of sodium hypochlorite and calcium silicate-based root canal sealer kills more biofilm cells in infected dentinal tubules.


Asunto(s)
Antibacterianos , Compuestos de Calcio , Enterococcus faecalis , Irrigantes del Conducto Radicular , Silicatos , Biopelículas , Calcio , Cavidad Pulpar , Dentina , Hipoclorito de Sodio
4.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 53(10): 681-687, 2018 Oct 09.
Artículo en Chino | MEDLINE | ID: mdl-30392225

RESUMEN

Objective: To evaluate the antimicrobial activity of nonequilibrium plasma against Enterococcus faecalis (Ef) biofilms in vitro and to obtain novel evidence of root canal disinfection with nonequilibrium plasma. Methods: Sterile cover slips and single-rooted canals were filled with Ef and incubated to form 1-week-old and 3-week-old biofilms, respectively. The infected samples were subjected to nonequilibrium plasma, 2% chlorhexidine digluconate (CHX) and saline for 3, 10 and 30 minutes, respectively. After treatment, the killing effectiveness of nonequilibrium plasma was analyzed by using laser scanning confocal microscopy (LSCM) and colony forming unit (CFU) counting. Results: The 3-dimentional reconstruction LSCM images showed that about 48.3%-79.8% of 1-week-old Ef biofilm cells and 40.0%-67.4% of 3-week-old biofilm cells were killed by nonequilibrium plasma and 2% CHX compared to saline (P<0.05). The proportion of killing activity was lower after 3 minutes (40.0%-50.9% killing) than after 10 minutes (65.3%-77.8% killing) and 30 minutes (66.4%-79.8% killing) (P<0.05). And the killing of biofilm bacteria was fastest during the first 3 minutes (13.3%-17.0% killing per minute) and slow down greatly after 10 minutes. Remarkably more bacteria were killed in 1-week-old Ef biofilms (48.3%-79.8% killing) than in 3-week-old biofilms (P<0.05). Conclusions: The nonequilibrium plasma killed more Ef biofilm cells in infected root canals showed promotional as an additional approach against bacterial biofilms during root canal disinfection.


Asunto(s)
Biopelículas , Cavidad Pulpar , Enterococcus faecalis , Infecciones por Bacterias Grampositivas , Microscopía Confocal , Irrigantes del Conducto Radicular , Tratamiento del Conducto Radicular , Hipoclorito de Sodio
5.
Eur Rev Med Pharmacol Sci ; 22(16): 5180-5186, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30178839

RESUMEN

OBJECTIVE: P3H4, as a kind of quinone compounds, is a coenzyme Q10 (ubiquinone) analogues. A recent study investigated the role of P3H4 on cerebral ischemia-reperfusion and hypertension. It is well known that ischemia-reperfusion is closely associated with kidney disease. This study aims to investigate the impact of P3H4 in the occurrence and development of the tumor. MATERIALS AND METHODS: A total of 40 rats at 8-week old were selected to establish renal cancer model by burying suture method for 4 months. The rats in the experimental group received P3H4 treatment at 100 mg/kg every 48 h for consecutive 4 weeks, while the rats in control received normal saline. H&E staining was applied to test the histological changes of tissue at 0, 1, 2 weeks after treatment. Gene microarray was adopted to screen miRNA expression to explore the function of miRNA in renal cancer cell line. Renal cancer cell migration and invasion were evaluated by wound healing and transwell assays after the treatment of P3H4, miR-1a, miR-133a, respectively. RESULTS: The rats were randomly equally divided into experimental group and control. HE staining result showed renal interstitial fibroblasts hyperplasia, renal tubular necrosis, and glomerular reduction after modeling. P3H4 treatment significantly alleviated the lesion severity and inhibited the tumor cells invasion. Microarray demonstrated that miR-1a and miR-133a were significantly upregulated in rat renal cancer tissue after the treatment of P3H4. The overexpression of miR-1a and miR-133a markedly reduced renal cell invasion and migration, which was consistent with the effect of P3H4. CONCLUSIONS: P3H4 suppressed the development of renal carcinoma through upregulating miR-1a and miR-13a, which provides fundamental leads for the future anti-cancer therapy.


Asunto(s)
Neoplasias Renales/metabolismo , Neoplasias Renales/prevención & control , MicroARNs/biosíntesis , Ubiquinona/análogos & derivados , Regulación hacia Arriba/efectos de los fármacos , Animales , Línea Celular Tumoral , Femenino , Masculino , MicroARNs/agonistas , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Ubiquinona/farmacología , Ubiquinona/uso terapéutico , Regulación hacia Arriba/fisiología
6.
Environ Monit Assess ; 189(8): 411, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28735434

RESUMEN

Assessment of groundwater quality plays a significant role in the utilization of the scarce water resources globally and especially in arid regions. The increasing abstraction together with man-made contamination and seawater intrusion have strongly affected groundwater quality in the Arabia Peninsula, exemplified by the investigation given here from the United Arab Emirates, where the groundwater is seldom reviewed and assessed. In the aim of assessing current groundwater quality, we here present a comparison of chemical data linked to aquifers types. The results reveal that most of the investigated groundwater is not suitable for drinking, household, and agricultural purposes following the WHO permissible limits. Aquifer composition and climate have vital control on the water quality, with the carbonate aquifers contain the least potable water compared to the ophiolites and Quaternary clastics. Seawater intrusion along coastal regions has deteriorated the water quality and the phenomenon may become more intensive with future warming climate and rising sea level.


Asunto(s)
Monitoreo del Ambiente , Agua Subterránea/química , Contaminantes Químicos del Agua/análisis , Agricultura , Agua Potable , Agua de Mar , Calidad del Agua/normas , Recursos Hídricos/provisión & distribución
7.
Artículo en Chino | MEDLINE | ID: mdl-28511315

RESUMEN

Objective: To perform a cost-benefit analysis of the occupational disease reporting system in China, and to provide a basis for effective resource allocation. Methods: The data on the cost of occupational diseases were collected from China Health Statistics Yearbook 2013, the estimated benefit data were collected from published articles in China and foreign countries, and the probability data were collected from the occupational diseasereports published by health and family planning administrative departments. Adecision-making tree was used for the cost-benefit analysis. Results: The estimated cost of occupational disease reporting was about 102.47 million yuan/year, consisting of a cost of reporting in national medical institutions of 1.25 million yuan/year, a management cost of 30.35 million yuan/year, a management cost in local public health institutions of 69.80 million yuan/year, a management cost in national public health institutions of 370 thousand yuan/year, and a cost of construction and maintenance of reporting system of 700 thousand yuan/year. The results of the decision tree analysis showed that when an occupational disease monitoring system was established, the incremental input for occupational disease monitoring and prevention/control was 2.1 billion yuan/year, the output was 6.5 billion yuan/year, and the benefit of occupational disease reporting system was 4.4 billion yuan/year. Conclusion: The benefit of occupational disease reporting system depends on the cost-benefit of occupational disease prevention and control measures, and proper prevention and control measures are extremely important for improving the benefit of occupational disease reporting system.


Asunto(s)
Análisis Costo-Beneficio , Enfermedades Profesionales/economía , China/epidemiología , Humanos , Enfermedades Profesionales/epidemiología
8.
Crit Rev Food Sci Nutr ; 52(5): 426-42, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22369261

RESUMEN

Plastic packaging for food and non-food applications is non-biodegradable, and also uses up valuable and scarce non-renewable resources like petroleum. With the current focus on exploring alternatives to petroleum and emphasis on reduced environmental impact, research is increasingly being directed at development of biodegradable food packaging from biopolymer-based materials. The proposed paper will present a review of recent developments in biopolymer-based food packaging materials including natural biopolymers (such as starches and proteins), synthetic biopolymers (such as poly lactic acid), biopolymer blends, and nanocomposites based on natural and synthetic biopolymers. The paper will discuss the various techniques that have been used for developing cost-effective biodegradable packaging materials with optimum mechanical strength and oxygen and moisture barrier properties. This is a timely review as there has been a recent renewed interest in research studies, both in the industry and academia, towards development of a new generation of biopolymer-based food packaging materials with possible applications in other areas.


Asunto(s)
Biopolímeros/química , Embalaje de Alimentos , Nanocompuestos/química , Poliésteres/química , Biopolímeros/metabolismo , Carbohidratos de la Dieta/análisis , Carbohidratos de la Dieta/metabolismo , Proteínas en la Dieta/análisis , Proteínas en la Dieta/metabolismo , Embalaje de Alimentos/tendencias , Poliésteres/metabolismo , Polihidroxialcanoatos/química , Polihidroxialcanoatos/metabolismo , Alcohol Polivinílico/química , Silicatos/química
9.
Phys Rev Lett ; 109(26): 269501; author reply 269502, 2012 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-23368626
10.
Phys Rev Lett ; 95(15): 155002, 2005 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-16241732

RESUMEN

In a linear driven problem with integral constraints, resonant phenomena can still persist but occur away from the fundamental frequencies of the unconstrained linear system. The frequency and the mode structure of the constrained resonances are found to be the intrinsic properties of the undriven and unconstrained linear systems. This is shown with a Taylor-relaxed magnetized plasma in a torus that conserves the net toroidal flux. The constrained resonance leads to a number of modifications to the standard paradigm of Taylor relaxation in a toroidal plasma.

11.
Phys Rev Lett ; 94(22): 225004, 2005 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-16090407

RESUMEN

Taylor relaxation in a driven plasma with normal magnetic field intercepting the boundary is described by the Jensen-Chu theory, which predicts infinite energy and helicity barriers that constrain the accessible relaxed states to system scale. For a partially relaxed force-free (j=kB) plasma where k is a field line constant, nonlinearity regularizes the Jensen-Chu singularities and new branches of relaxed state become accessible, such as the flipped spheromak and other high k states.

12.
Chaos ; 9(1): 183-194, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12779812

RESUMEN

We consider the design criteria of a chemical mixing device based on a chaotic flow, with an emphasis on the steady-state devices. The merit of a reactor, defined as the Q-factor, is related to the physical dimension of the device and the molecular diffusivity of the reactants through the local Lyapunov exponents of the flow. The local Lyapunov exponent can be calculated for any given flow field and it can also be measured in experimental situations. Easy-to-compute formulae are provided to estimate the Q-factor given either the exact spatial dependence of the local Lyapunov exponent or its probability distribution function. The requirements for optimization are made precise in the context of local Lyapunov exponents. (c) 1999 American Institute of Physics.

13.
Chaos ; 8(3): 688-696, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12779773

RESUMEN

Converting a continuous signal into a multisymbol stream is a simple method of data compression which preserves much of the dynamical information present in the original signal. The retrieval of selected types of information from symbolic data involves binary operations and is therefore optimal for digital computers. For example, correlation time scales can be easily recovered, even at high noise levels, by varying the time delay for symbolization. Also, the presence of periodicity in the signal can be reliably detected even if it is weak and masked by a dominant chaotic/stochastic background. (c) 1998 American Institute of Physics.

14.
Cancer Res ; 55(23 Suppl): 5736s-5742s, 1995 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-7493338

RESUMEN

An IgM lambda human tumor cell-reactive monoclonal antibody was developed that reacts with cells of ovarian cancer, colorectal cancer, breast cancer, and certain other malignancies. The monoclonal antibody AC6C3-2B12, which was obtained from a recent recloning, was purified from tissue culture supernatants and analyzed by high-performance liquid chromatography and sodium dodecyl sulfate-PAGE. An animal model was developed in which human tumors grew either as solid peritoneal metastases or as s.c. nodules utilizing the human colorectal carcinoma cell line SW620. The biodistribution of 111In-labeled IgM conjugate was studied after i.v. or i.p. administration in nude mice bearing an s.c. xenograft or peritoneal tumor lumps of a human colorectal carcinoma (SW620). IgM administered i.v. cleared rapidly from blood and was deposited mainly in the liver [50% injected dose/g (ID)/g)], pancreas (20% ID/g), and kidney (10% ID/g) at 24 h. Tumor deposition was low (< or = 1.0% ID/g) in the s.c. tumor xenograft. In contrast, high tumor targeting (29% ID/g) was found in peritoneal tumor lumps after i.p. administration of 111In-labeled IgM. The biological half-life of IgM in the tumor was 100 h. Long peritoneal residence time (t 1/2 = 67 h) and low liver uptake (7% ID/g) were observed after i.p. administration. Blood activity was < 1% of the injected activity. Tumor:normal organ ratios were high (range, 2-290) from 2 to 144 h after i.p. administration. Whole body autoradiograms at 24 h after i.p. 111In-labeled IgM administration confirmed the biodistribution results. In normal beagle dogs, 75% of the i.p.-administered 111In-IgM decayed in the peritoneal cavity. The majority of the remaining radioactivity was taken up by mediastinal lymph nodes. Biological half-life in both locations was approximately 137 h. The i.p. administration of intact, specific radiolabeled IgM provides prolonged retention of radioactivity in tumor, low normal tissue uptake, a long peritoneal residence time, and very limited spillover of IgM into the circulation. This approach offers a promising new method for the diagnosis and treatment of certain patients with peritoneal carcinomatosis.


Asunto(s)
Anticuerpos Antineoplásicos/uso terapéutico , Neoplasias Colorrectales/radioterapia , Inmunoglobulina M/uso terapéutico , Radioisótopos de Indio/uso terapéutico , Radioinmunoterapia , Animales , Autorradiografía , Perros , Humanos , Ratones , Ratones Desnudos , Ácido Pentético
15.
Radiat Res ; 141(3): 294-302, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7871156

RESUMEN

High-dose radiation therapy for liver metastases of gastrointestinal malignancies might be improved by combining external-beam irradiation and radioimmunoglobulin therapy. We studied the liver toxicity of the proposed combination in healthy beagle dogs. A total dose of 30 Gy to the whole liver, delivered in 2-Gy fractions over 3 weeks, resulted in mild, temporary veno-occlusive disease (VOD) in three of three dogs. Reversible bone marrow damage was noted after two intravenous injections of 18.5 MBq of yttrium-90-labeled monoclonal antibody ZCE025 per kg body weight in three of three dogs. Administrations of the antibody were separated by 1 week. Three dogs treated by irradiation of the liver with radioimmunoglobulin therapy added during the last 2 weeks of the irradiation showed signs of radiation hepatitis (VOD) starting around 35 days after treatment. One dog had a complete recovery, and two dogs were euthanized in a stage of terminal liver failure around day 90 after treatment. Temporary bone marrow damage was observed after the combined treatment, similar to the bone marrow damage observed after radioimmunoglobulin therapy alone. Earlier studies in the same dog model showed that bone marrow is the dose-limiting organ if radioimmunoglobulin therapy is used alone. The addition of irradiation of the liver to radioimmunoglobulin therapy changes the dose-limiting organ from bone marrow to liver. The radiation hepatitis observed in dogs is very similar to that observed in humans and is reflected in early platelet consumption in the irradiated liver plus late elevations of liver enzymes and VOD in central hepatic veins on histological analysis. Future applications of combined liver irradiation and radioimmunoglobulin therapy in humans should use radioimmunoglobulin therapy agents which show minimal uptake by normal liver.


Asunto(s)
Anticuerpos Monoclonales/farmacocinética , Hígado/efectos de la radiación , Radioinmunoterapia , Animales , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/uso terapéutico , Perros , Femenino , Radioisótopos de Indio/farmacocinética , Masculino , Radioinmunoterapia/efectos adversos , Radioisótopos de Itrio/farmacocinética
16.
J Tongji Med Univ ; 14(4): 242-4, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7760438

RESUMEN

A correct estimation of the collagen content in cirrhosis liver tissue and analysis of its relation to the degree of liver function injury are important to the clinician in the establishment of the diagnosis in the liver diseases. The author has performed the morphometric measurement of collagen with liver tissue pathological section by using TJTY-300 image analysis system. It was found that the cirrhotic liver tissue's collagen area and collagen average grey degree were notably higher than those in normal men (P < 0.05), average optical density was markedly lower than that in normal men (P < 0.05), integral optical density had no significant difference (P > 0.05) between patients and normal controls, but the integral optical density in cirrhotic liver was 1.21 times that of normal men. It suggests that the collagen content in cirrhotic liver tissue increased obviously, the average density of the increased collagen was lower than that in the normal liver tissue and the density of increased collagen was not homogeneous. Comparison between normal controls and patients with different Child-Pugh liver function grades in liver tissue collagen parameters revealed that the cirrhotic liver's collagen content can, to different degree, directly reflect the function status of cirrhotic liver.


Asunto(s)
Colágeno/análisis , Hipertensión Portal/metabolismo , Cirrosis Hepática/complicaciones , Hígado/química , Adulto , Femenino , Hepatitis Viral Humana/complicaciones , Humanos , Hipertensión Portal/etiología , Masculino , Persona de Mediana Edad
17.
Sci Sin B ; 31(7): 860-72, 1988 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2904697

RESUMEN

Human mitochondrial DNA (mtDNA) restriction endonuclease fragment patterns were analyzed using placenta DNA isolated from 273 individuals representing four different nationalities, the Han, the Uygur, the Kazakh and the Hui populations. Thirty-eight fragment patterns (morphs) were observed with the enzyme ApaI, BamHI, EcoRI, HindIII, HinfI, HhaI, HapII, KpnI, Mbol, PstI, PvuII, SacI, ScaL and XhoI. Fourteen new morphs, including some only existing in individual racial and national populations were observed, which indicates that there is a significant difference in the distribution of mtDNA morphs among various national and racial populations. By comparison with the mtDNA sequences in primate species, some mtDNA ancestral morphs were found to be retained in Oriental population today. This result provided indirect evidence that Asia may be one of the human original sources. Genetic distances among four national populations computed and employed in construction of an average linkage tree suggested that the Uygur and the Kazakh populations combined to form a branch at first, then the Han and the Hui came together to form another one, and at last, these two branches converged into a stem. Again, it was found that the internal variation within the Uygur and the Kazakh populations was greater than that within the Han and the Hui populations. These results showed a relationship among the four different national populations in China based on the molecular level.


Asunto(s)
ADN Mitocondrial/genética , Polimorfismo Genético , Polimorfismo de Longitud del Fragmento de Restricción , China , ADN Mitocondrial/aislamiento & purificación , Etnicidad , Humanos , Placenta/análisis , Especificidad de la Especie
18.
Biosci Rep ; 4(12): 1071-7, 1984 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6099156

RESUMEN

The erythroleukemia cell line K562 was previously shown to have specific binding sites for insulin but not for insulin-like growth factor I (IGF-I). In this study the presence of specific receptors for insulin-like growth factor II (IGF-II) is established. Scatchard analysis of the competition curve for IGF-II disclosed a non-cooperative binding kinetic with a calculated affinity constant 2.4 X 10(8) M-1 and a receptor number of 4.8 X 10(4) sites/cell. IGF-I displayed 10% crossreactivity over the IGF-II receptor but insulin did not crossreact at all. Instead insulin, present in high concentrations, enhanced the binding of IGF-II. The presence of IGF II but not IGF-I receptors makes the K562 cell line suitable for studying properties of the type-2 receptor.


Asunto(s)
Insulina/metabolismo , Leucemia Eritroblástica Aguda/metabolismo , Péptidos/metabolismo , Somatomedinas/metabolismo , Sitios de Unión , Unión Competitiva , Línea Celular , Humanos , Cinética , Receptores de Superficie Celular/metabolismo , Receptores de Somatomedina
19.
Biochem Biophys Res Commun ; 117(3): 823-34, 1983 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-6582851

RESUMEN

The K 562 is a transformed human erythroid stemcell and is used as a target cell for NK-T-cells. In this study the presence of insulin receptors in K 562 is established. The best binding and negative cooperativity was found in the two Hepes containing buffers whereas no cooperativity was obtained in the Krebs-Ringer buffer. The calculated affinity constants and receptor number per cell varied according to the buffer. Preincubation with insulin caused a down-regulation of the insulin binding capacity. 10 ng/ml caused a lowering of the affinity, with an unchanged number of receptors. 100 ng/ml caused a decrease in receptor number with unchanged affinity. These results were found in both Hepes and Krebs-Ringer phosphate buffer. IGF-I shows cross-reactivity with the insulin receptor, with a potency of 12 and 100 times less than insulin in Krebs-Ringer phosphate buffer and G-buffer respectively. However, no specific IGF-I receptors were found. The presence of receptors on K 562 cells suggests a biological role for insulin. The different results in the different buffers, indicate that a buffer containing Hepes and/or Tris, is required to expose negative cooperativity and make the receptors more accessible to insulin.


Asunto(s)
Leucemia Eritroblástica Aguda/metabolismo , Receptor de Insulina/aislamiento & purificación , Unión Competitiva , Tampones (Química) , Línea Celular , Humanos , Cinética
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