RESUMO
Objective: To perform intrauterine adhesion modeling, and to investigate the repair effect of hypoxic treated bone marrow mesenchymal stem cells (BMSC) and their derived exosomes (BMSC-exo) on endometrial injury. Methods: BMSC and their exosomes BMSC-exo extracted from rats' femur were cultured under conventional oxygen condition (21%O2) or hypoxia condition (1%O2). Intrauterine adhesion modeling was performed on 40 healthy female SD rats by intrauterine injection of bacterial lipopolysaccharide after curettage. On the 28th day of modeling, 40 rat models were randomly divided into five groups, and interventions were performed: (1) NC group: 0.2 ml phosphate buffered solution was injected into each uterine cavity; (2) BMSC group: 0.2 ml BMSC (1×106/ml) with conventional oxygen culture was injected intrauterine; (3) L-BMSC group: 0.2 ml of hypoxic cultured BMSC (1×106/ml) was injected intrauterine; (4) BMSC-exo group: 0.2 ml of BMSC-exo cultured with conventional oxygen at a concentration of 500 µg/ml was injected into the uterine cavity; (5) L-BMSC-exo group: 0.2 ml hypoxic cultured BMSC-exo (500 µg/ml) was injected intrauterine. On the 14th and 28th day of treatment, four rats in each group were sacrificed by cervical dislocation after anesthesia, and endometrial tissues were collected. Then HE and Masson staining were used to observe and calculate the number of glands and fibrosis area in the endometrium. The expressions of angiogenesis related cytokines [vascular endothelial growth factor A (VEGFA) and CD31], and fibrosis-related proteins [collagen-â , collagen-â ¢, smooth muscle actin α (α-SMA), and transforming growth factor ß1 (TGF-ß1)] in endometrial tissues were detected by western blot. Results: (1) HE and Masson staining showed that the number of endometrial glands in L-BMSC group, BMSC-exo group and L-BMSC-exo group increased and the fibrosis area decreased compared with NC group on the 14th and 28th day of treatment (all P<0.05). Noteworthily, the changes of L-BMSC-exo group were more significant than those of BMSC-exo group (all P<0.05), and the changes of BMSC-exo group were greater than those of BMSC group (all P<0.05). (2) Western blot analysis showed that, compared with NC group, the expressions of collagen-â ¢ and TGF-ß1 in BMSC group, L-BMSC group, BMSC-exo group and L-BMSC-exo group decreased on the 14th and 28th day of treatment (all P<0.05). As the treatment time went on, the expressions of fibrosis-related proteins were different. Compared with BMSC group, the expressions of collagen-â ¢, α-SMA and TGF-ß1 in the BMSC-exo group and L-BMSC group decreased on the 28th day (all P<0.05). Moreover, the expressions of collagen-â ¢ and TGF-ß1 in L-BMSC-exo group were lower than those in BMSC-exo group on the 28th day (all P<0.05). And the expressions of collagen-â , α-SMA and TGF-ß1 in L-BMSC-exo group were lower than those in L-BMSC group on the 28th day (all P<0.05). (3) The results of western blot analysis of VEGFA and CD31 showed that, the expressions of VEGFA and CD31 in BMSC group, L-BMSC group, BMSC-exo group and L-BMSC-exo group increased on the 14th and 28th day of treatment compared with NC group (all P<0.05). Treatment for 28 days, the expressions of VEGFA and CD31 in BMSC-exo group and CD31 in L-BMSC group were higher than those in BMSC group (all P<0.05). Moreover, the expressions of VEGFA and CD31 in L-BMSC-exo group were higher than those in BMSC-exo group and L-BMSC group on the 28th day (all P<0.05). Conclusions: Treatment of BMSC and their exosomes BMSC-exo with hypoxia could promote endometrial gland hyperplasia, inhibit tissue fibrosis, and further repair the damaged endometrium in rats with intrauterine adhesion. Importantly, hypoxic treatment of BMSC-exo is the most effective in intrauterine adhesion rats.
Assuntos
Exossomos , Células-Tronco Mesenquimais , Doenças Uterinas , Ratos , Feminino , Humanos , Animais , Ratos Sprague-Dawley , Fator de Crescimento Transformador beta1/metabolismo , Fator A de Crescimento do Endotélio Vascular , Exossomos/metabolismo , Doenças Uterinas/terapia , Colágeno , Hipóxia/terapia , Fibrose , Células-Tronco Mesenquimais/metabolismo , OxigênioRESUMO
Objective: To analyze the trend of liver cancer morbidity and mortality among residents with household registration in certain District, 2017 to 2019. Methods: The crude morbidity and mortality rate of males and females in the whole population were calculated by using the relevant data from the certain District Cancer Registry and Report System and the Cause of Death Surveillance System. The standardized morbidity and mortality rate were calculated according to the age structure of 2000 National Demographic Census and Segi's world population, respectively. Trend in liver cancer morbidity and mortality were evaluated using percent change (PC), annual percentage change, and case-number-weighted annual percent change. Age-specific rates were used to analyze the epidemic trend of liver cancer with age. Results: The crude morbidity rate of liver cancer in the whole population (male and female) of the certain district from 2017 to 2019 were 18.86/100 000, 26.05/100 000 and 11.90/100 000 respectively, and the crude mortality rates were 21.20/100 000, 29.29/100 000 and 13.38/100 000 respectively. The crude morbidity and mortality rate of liver cancer among male showed a downward trend (PC=-16.77% and -20.15% respectively). The crude morbidity and mortality rate of liver cancer among female showed inconsistent changes; however, the crude morbidity rate showed a downward trend, and the crude mortality rate first increased and then decreased (PC=-19.42% and -0.30% respectively). Liver cancer morbidity and mortality rate in male after the age of 30 were increased with age. The two key points of accelerated growth were around the age of 65 and 75, and the peak of morbidity (130.78/100 000) and mortality (201.96/100 000) were after the age of 80. The morbidity and mortality rate were significantly lower in female than those of male aged 60; however, after the age of 65, the morbidity rate was increased rapidly and gradually approached as that of male. After the age of 80 (the peak morbidity and mortality were 104.40/100,000 and 132.87/100,000, respectively), male were about twice as high as those female aged between 75 and 79. Conclusion: Morbidity and mortality rate of liver cancer in the certain District showed an overall downward trend from 2017 to 2019, but it increased with age, and the disease burden was relatively high among the elderly population. Liver cancer mostly occurred in male, so the prevention and control of liver cancer epidemics in middle-aged and elderly should be actively monitored.
Assuntos
Neoplasias Hepáticas , Idoso , China/epidemiologia , Feminino , Humanos , Incidência , Neoplasias Hepáticas/epidemiologia , Masculino , Pessoa de Meia-Idade , Morbidade , Sistema de Registros , População UrbanaRESUMO
Piglet diarrhea epidemics result in major economic losses for the swine industry. Four viruses are closely linked to porcine diarrhea: porcine kobuvirus (PKV), porcine epidemic diarrhea virus (PEDV), porcine transmissible gastroenteritis virus (TGEV), and porcine rotavirus (PRoV). We have conducted an epidemiology study to determine the frequency of infection and co-infection with these viruses in China, and characterized the genetic variation of the isolated PEDV and PKV strains. Stool and intestinal samples (n = 314) were collected from piglets with diarrhea in China from years 2012 to 2014. RT-PCR was used to detect PKV, PEDV, TGEV, and PRoV. Phylogenetic relationships between reference strains and the isolated PEDV and PKV strains were determined based on the M and 3D gene sequence. The rates of infection with PKV, PEDV, TGEV and PRoV were 29.9%, 24.2%, 1.91%, and 0.31%, respectively. Co-infections with PKV and the other three viruses were very common. Co-infection of PKV and PEDV was detected in 15.0% (47/314) of the samples. Phylogenetic analysis of the PKV 3D gene indicated that there were some phylogenetic differences in the PKV strains across regions within China. However, according to the PEDV M gene, strains clustered into three groups and the primary group was distinct from the vaccine strain CV777. This study provides insights in to the prevalence of diarrhea viruses and their prevention and control in China.
Assuntos
Coinfecção/veterinária , Diarreia/veterinária , Kobuvirus/fisiologia , Vírus da Diarreia Epidêmica Suína/fisiologia , Doenças dos Suínos/virologia , Animais , China/epidemiologia , Coinfecção/epidemiologia , Coinfecção/virologia , Diarreia/epidemiologia , Diarreia/virologia , Fezes/virologia , Kobuvirus/genética , Kobuvirus/isolamento & purificação , Dados de Sequência Molecular , Filogenia , Vírus da Diarreia Epidêmica Suína/genética , Vírus da Diarreia Epidêmica Suína/isolamento & purificação , Suínos , Doenças dos Suínos/epidemiologiaRESUMO
UNLABELLED: Differential osteogenic potential and responsiveness to 17ß-estradiol (E2) of mesenchymal stem cells (MSCs) were found between postmenopausal women with osteoporosis (OP) and osteoarthritis (OA). These results suggest differential biological mechanisms of estrogen deficiency in regulation of bone remodeling between OP and OA. INTRODUCTION: OP and OA are two common disorders in postmenopausal women. The inverse relationship has been suggested between OP and OA, but their mechanisms that relate to estrogen deficiency are not fully understood. The aim of this study was to compare the differential responsiveness to E2 of MSCs from osteoporotic versus osteoarthritic donors. METHODS: Twenty postmenopausal patients, ten with osteoporotic hip fractures and ten with hip osteoarthritis, were included into this study. MSCs were derived from cancellous bones of femoral heads from OA and OP donors and cultured in osteogenic and adipogenic medium with or without E2 added. The alkaline phosphatase (ALP) activity, calcium content, calcified nodules, lipid droplets, messenger RNA (mRNA) expression of ALP, osteocalcin (OC), collagen 1α (COL1α), peroxisome proliferators-activated receptor γ2 (PPARγ2) and lipoprotein lipase (LPL) were measured and compared between two groups with OP and OA. RESULTS: In osteogenic medium, ALP activity, calcium content and mRNA expression of OC and COL1α in MSCs from OA were significantly higher than those from OP group. In adipogenic condition, there was no significant difference in lipid droplets formation and mRNA expression of PPARγ2 and LPL between OP and OA groups. With E2 added in osteogenic medium, ALP activity, calcium content and OC mRNA were significantly higher in OP group than in OA group, whereas E2 had no significant effect on lipid droplet formation and mRNA expression of PPARγ2 and LPL. CONCLUSION: Differential osteogenic potential and responsiveness to E2 of MSCs were found between postmenopausal women with OP and OA. These results may provide information for clinical application of MSCs in the differential setting of estrogen deficiency.
Assuntos
Estradiol/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteoartrite do Quadril/patologia , Osteoporose Pós-Menopausa/patologia , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/metabolismo , Cálcio/metabolismo , Células Cultivadas , Feminino , Cabeça do Fêmur/patologia , Fraturas do Quadril/etiologia , Fraturas do Quadril/metabolismo , Fraturas do Quadril/patologia , Humanos , Células-Tronco Mesenquimais/metabolismo , Osteoartrite do Quadril/metabolismo , Osteocalcina/metabolismo , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/metabolismo , Fraturas por Osteoporose/metabolismo , Fraturas por Osteoporose/patologiaRESUMO
Ovarian cortical tissues of various ages of chicken were grafted underneath chorioallantoic membrane (CAM) of 6-d-old chicken embryo and the grafts were collected on d 0, 2, 4, 8, or 10. The tissue sections were prepared to examine the development of follicles in grafts and the proliferative ability of follicles was examined by immunohistochemistry analysis of proliferating cell nuclear antigen. The results indicated that the development of follicles in cultured chicken ovarian cortical pieces progressed smoothly and slowly similar to those in vivo, and the environment of chicken embryo was more suitable for the synchronous development of oocyte and follicular cells in the larger follicles. Meanwhile, the synchronous development could be more easily achieved in the chicken ovarian tissues of 12- to 15-wk chicken. Neither oocyte nor granulosa cells but the thecal cells of follicles developed in grafts of 13- to 15-d chicken within 10 d of culturing in ovo, and the CAM can ease follicular atresia in chicken ovarian grafts of 12- to 15-wk chicken. The proliferative performance of follicles in the grafts was not influenced by the environment of chicken embryo. These results indicated that the chicken embryo has the ability to support slow development of primordial and primary follicles in grafted ovarian cortical tissues of chickens of different ages. The CAM system may also prove useful for the study of early follicle development with further information.
Assuntos
Embrião de Galinha , Galinhas/fisiologia , Membrana Corioalantoide/fisiologia , Ovário/fisiologia , Envelhecimento , Animais , Feminino , Regulação da Expressão Gênica/fisiologia , Imuno-Histoquímica , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Fatores de Tempo , Técnicas de Cultura de TecidosRESUMO
Various classification systems have been proposed for fractures of the distal radius, but the reliability of these classifications are seldom addressed. The objective of this study was to determine the interobserver and intraobserver reliability of the Cooney classification. Five orthopaedic surgeons with more than 10 years' experience in orthopaedic trauma assessed 43 sets of radiographic files according to the Cooney classification separately. Kappa statistics were used to analyse the interobserver and intraobserver reliability. There was moderate and substantial interobserver and intraobserver reliability of the Cooney classification without subtype, but only slight reliability when the subgroups were considered. These results question the value of this classification system for treatment decision making.
Assuntos
Ortopedia/estatística & dados numéricos , Fraturas do Rádio/classificação , Traumatismos do Punho/classificação , Ossos do Carpo/diagnóstico por imagem , Ossos do Carpo/lesões , Ossos do Carpo/cirurgia , Humanos , Variações Dependentes do Observador , Radiografia , Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/cirurgia , Reprodutibilidade dos Testes , Traumatismos do Punho/cirurgiaRESUMO
It is well established that testicular differentiation of the human embryonic gonad depends on the action of the Y-chromosomal gene SRY. However, exceptional cases such as SRY-negative cases of 46,XX testicular disorder of sexual development (DSD), and of 46,XX ovotesticular DSD document that testicular tissue can develop in the absence of the SRY gene. These SRY-negative XX sex reversal cases are very rare and usually sporadic, but a few familial cases have been reported. We present a large, consanguineous family with nine affected individuals with phenotypes ranging from 46,XX testicular DSD to 46,XX ovotesticular DSD, with predominance of male characteristics. Absence of SRY in peripheral blood was documented by fluorescence in situ hybridization (FISH) and PCR analysis in all nine affected individuals, and by FISH analysis on gonadal sections with testicular tissue in four affected individuals. By quantitative PCR, a duplication of the SOX9 gene was excluded. In addition, as linkage analysis showed that the nine affected members of the family do not share a common SOX9 haplotype, any mutation at the SOX9 locus could be ruled out. Together, these findings implicate a mutation at a sex-determining locus other than SRY and SOX9 as the cause for the XX sex reversal trait in this family.
Assuntos
Transtornos do Desenvolvimento Sexual , Proteínas de Grupo de Alta Mobilidade/genética , Mutação/genética , Linhagem , Proteína da Região Y Determinante do Sexo/deficiência , Fatores de Transcrição/genética , Adolescente , Adulto , Criança , Pré-Escolar , Análise Citogenética , Proteínas do Domínio Duplacortina , Feminino , Regulação da Expressão Gênica , Haplótipos , Proteínas de Grupo de Alta Mobilidade/metabolismo , Hormônios/sangue , Humanos , Masculino , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOX9 , Proteína da Região Y Determinante do Sexo/genética , Proteína da Região Y Determinante do Sexo/metabolismo , Testículo/patologia , Fatores de Transcrição/metabolismoRESUMO
The photoinduced electron donor acceptor interactions of C60 with eight kinds of aliphatic amines, namely dicthylamine (DEA), triethylamine (TEA), tri-n-amylamine (TAA), propylethylamine (PPA), n-butylamine (BTA), n-heptylamine (HPA) and dodecylamine (DDA) and ethylenediamine (EDA) are reported by a comprehensive spectroscopic study. Experiments show that there is a good discipline with different structure and the length of n-alkyl group both in their ground and excited states. At the same time, a slow reaction takes place between C60 and various amines with a gradual increase in the concentration of various aliphatic amines or the standing of solution, which can be dramatically catalyzed by UV-radiation. The final products can all emit a strong fluorescence at the relatively shorter wavelength around 519 nm. On this basis, the dynamic properties of C60/aphaliticamines including the enthalpy of activation (deltaH++et) and entropy activation (deltaS++et), together with all sorts of influence factors are firstly investigated in this work. The possible reaction mechanisms are explored, also.
Assuntos
Aminas/química , Carbono/química , Fulerenos , Fármacos Fotossensibilizantes/química , Fotoquímica , Espectrometria de Fluorescência , Espectrofotometria , Relação Estrutura-AtividadeRESUMO
The binding reaction between sparfloxacion (SPFX) and bovine serum albumin (BSA) or chicken egg albumin (CEA) in aqueous was studied using fluorescence and absorption spectra. Their binding constants are KCEA = 8.29 x 10(6) and KBSA = 4.41 x 10(7), and the binding sites are nCEA = 0.558, nBSA = 0.793 respectively. The action distances (RCEA = 1.99 nm, RBSA = 2.09 nm) and energy transfer efficiencies (ECEA = 0.766, EBSA = 0.714) between donor-acceptor and SPFX were obtained by Förster's nonradiative energy transfer mechanism. The experiment demonstrated that the higher the temperature is, the lower the slopes of quenching curves of BSA and CEA are in presence of different amounts of SPFX. It is confirmed that the combination for SPFX with BSA or CEA is a single static quenching process, their interaction may be interpreted with energy transfer mechanism. Through binding reaction of the two albumins with SPFX, the biological effects and action mechanism of SPFX with albumins in vivo were discussed.
Assuntos
Proteínas do Ovo/metabolismo , Fluoroquinolonas/química , Fluoroquinolonas/metabolismo , Soroalbumina Bovina/metabolismo , Albuminas/metabolismo , Animais , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Sítios de Ligação , Bovinos , Galinhas , Proteínas do Ovo/química , Transferência de Energia , Humanos , Ligação Proteica , Soroalbumina Bovina/química , Espectrometria de Fluorescência/métodos , Espectrofotometria Ultravioleta/métodosRESUMO
At pH 3,S,R enantioners of ofloxacin can be well recognized by the synchronous-first derivative fluorimetry. Based on this, a new method for the recognition and determination of enantiomers of ofloxacin, the synchronous-first order derivative fluorimetry has been developed. The linear range is 0.36-2.16 micrograms.mL-1(R), 0.36-2.89 micrograms.mL-1(S), and 3.16-31.6 micrograms.mL-1(S). The detection limit is 0.36 microgram.mL-1, RSD is less than 6.6%, and the recovery is within the range of 97%%-104%. The transformation of S- to R- (+)-ofloxacin enantiomer in human body is founded. In 0-3 h after taking ofloxacin tablets by a healthy subject, R-enantiomer can not be detected. At the 6th hour, remarkable amount of R-enantiomer was detected, and then R-/S-enantiomer ratio increased rapidly to 21.3% at the 24th hour for 2.1% at the 6th hour.
Assuntos
Anti-Infecciosos/farmacocinética , Ofloxacino/farmacocinética , Anti-Infecciosos/urina , Fluorometria/métodos , Humanos , Ofloxacino/urina , Espectrometria de Fluorescência/métodos , EstereoisomerismoRESUMO
Under controlling pH 3, R-(+)- and S-(-)-ofloxacin (OFLX) enantiomers can be well recognized and resolved by the synchronization-1st derivative fluorescence spectroscopic techniques, and the interference from urine blank also can be eliminated. The linear dynamic ranges are 0.36-2.16 (R), 0.36-2.89 and 3.16-31.6 mug/ml (S), respectively, for determining OFLX in urine samples. The limits of detection are 0.36 mug/ml (R) and the recoveries of R-(+)- and S-(-)-OFLX in urine samples are 97-104%. Relative standard deviation is <6.6%. Pharmacokinetic study of OFLX and levofloxacin shows that R-(+)- and S-(-)-ofloxacin reach their peak concentration in urine samples after a healthy subject has taken tablets for approximately 3 and 6 h, respectively. R-(+)-OFLX can be obviously detected in 5-6 h after a healthy subject has taken tablets, indicating the transformation of S-(-)- to R-(+)-OFLX enantiomer in human body (in vitro).
RESUMO
A fluorescence probe of 3-methoxybenzanthrone (MBA) exhibits significant solvatochromic characteristics correlated with the polarity of solvents. The interaction of the solvatochromic fluorescence probe with calf thymus DNA (ct-DNA) has been investigated. In the presence of ct-DNA the fluorescence of MBA is strongly quenched with a blue-shift of emission peak and a hypochromism in absorption spectra. The absorption spectra, fluorescence quenching and fluorescence polarization experiments show that the MBA molecule as an intercalator is inserted into the base-stacking domain of the ct-DNA double helix, and the interaction of the nucleobases with the MBA molecule causes quenching of fluorescence and hypochromism in the absorption spectra. The intrinsic binding constant and the binding site number were determined to be 1.70 x 10(5) mol l-1 in base pairs and six, respectively. The I0/I versus [ct-DNA] plot shows linear relationship in the range covering 4.3 x 10(-7)-1.02 x 10(-4) mol l-1 in base pairs which can be used for ct-DNA determination. The limit of detection was found to be 4.3 x 10(-7) mol l-1 in base pairs (0.5 microgram ml-1).
Assuntos
Benzo(a)Antracenos/química , Benzo(a)Antracenos/metabolismo , DNA/química , DNA/metabolismo , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Absorção , Acetona/química , Animais , Ânions , Pareamento de Bases , Bovinos , Polarização de Fluorescência , Concentração de Íons de Hidrogênio , Sais , Solventes , Espectrometria de Fluorescência , Análise Espectral/métodos , Temperatura , Timo/fisiologiaRESUMO
Permanent withdrawal of skeletal myoblasts from the cell cycle precedes differentiation. We examined the changes of protein levels of cell cycle regulators and the activities of CDKs in differentiating (by serum deprivation) or in differentiation-inhibited (by serum deprivation + TGF-beta1 treated) C2C12 skeletal myocytes. Regardless of differentiation, protein levels of most cyclins declined over time while this effect was delayed slightly by TGF-beta1 for cyclins D1 and F. Although the protein levels of CDKs gradually decreased over time, the activities of CDK2 and cdc2 decreased dramatically between 0 and 12 h after serum deprivation in both groups. Decreased CDK2 and cdc2 activities were temporally related to decreased DNA synthesis. While the p27KIP1 protein increased in both groups, the p21CIP1 protein increased only in differentiating cells. In vivo, protein expressions of cyclins, CDKs, and p21CIP1 were high in fetal, but almost undetectable in adult skeletal muscle. In contrast, the levels of p27KIP1 protein in skeletal muscle were high throughout development. Thus, changes of cell cycle regulators in differentiating C2C12 myocytes paralleled those during skeletal muscle development of mice. These results suggest that the rapid reduction of DNA synthesis and activities of CDKs slow reduction of protein levels of cyclins and CDKs, and that the increase of p27KIP1 are programmed mechanisms upon mitogen deprivation regardless of differentiation in skeletal myocytes.
Assuntos
Proteínas de Ciclo Celular/efeitos dos fármacos , Meios de Cultura/farmacologia , Músculo Esquelético/efeitos dos fármacos , Proteínas Supressoras de Tumor , Animais , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular , Inibidor de Quinase Dependente de Ciclina p21 , Inibidor de Quinase Dependente de Ciclina p27 , Quinases Ciclina-Dependentes/efeitos dos fármacos , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/efeitos dos fármacos , Ciclinas/metabolismo , DNA/biossíntese , DNA/efeitos dos fármacos , Feto/metabolismo , Camundongos , Proteínas Associadas aos Microtúbulos/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/metabolismo , Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Timidina/metabolismo , Fator de Crescimento Transformador beta/farmacologia , TrítioRESUMO
A comparison has been made for the quenching effect of three classes of organic solvents on the porous silicon photoluminescence, including hydrocarbons, solvents containing oxygen and nitrogen. Among them organoamines possess the strongest quenching effect. The experiments show that the solvent molecules interact synergistically with porous silicon and the main pathways include the surface hydrophobic interaction, dipole-dipole interaction and hole trapping, the later being the dominant pathway in quenching of porous silicon photoluminescence.
Assuntos
Solventes , Hidrocarbonetos , Luminescência , Silício , Relação Estrutura-AtividadeRESUMO
RESULTS: Based on the mathematical model of high-level expression of heterologous genes in prokaryotic vector pBV220, we developed a program GeneDn for high-level expression design of natural and synthetic genes. AVAILIBILITY: The program is written in Turbo Pascal 7.0. The source code and related material are available upon request. CONTACT: wujj@nic.bmi.ac.cn
Assuntos
Expressão Gênica , Software , Algoritmos , Biologia Computacional , Escherichia coli/genética , Vetores Genéticos , Humanos , Modelos Genéticos , Proteínas Recombinantes/genéticaRESUMO
Fluorescence quenching of free and DNA-bound ethidium bromide (EB) by a number of quaternary ammonium and other compounds was studied. For free EB or bound EB at lower DNA concentration the fluorescence quenching follows the Stern-Volmer equation and at higher DNA concentration follows an exponential model. At least at low quencher concentrations the quenching efficiency varies with DNA or NaCl concentrations and is about 100 times greater for bound than free EB. The quenching pathways may involve energy transfer and conformational loosening or distortion of the DNA helix in addition to possible electron transfer.
Assuntos
DNA/metabolismo , Etídio/química , Fluorescência , Porfirinas/química , Tensoativos/farmacologia , Detergentes/metabolismo , Substâncias Intercalantes/química , Estrutura Molecular , Conformação de Ácido Nucleico , Porfirinas/metabolismo , EspectrofotometriaRESUMO
Two hundred and eighty-seven renal-transplanted recipients treated with cyclosporine were monitored for their cyclosporine trough blood level periodically. Based on the monitor results, we now can define the ideal therapeutic range of cyclosporine in whole blood as follows: 500-600 ng/ml in the first week of post-transplantation, 600-800 ng/ml in the second week to sixth month of post-transplantation, 400-600 ng/ml in the seventh to twelfth month of post-transplantation and 350-400 ng/ml 1 year after post-transplantation.