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1.
Ultrasound Obstet Gynecol ; 57(5): 798-803, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-32770786

RESUMEN

OBJECTIVES: To evaluate the accuracy of an automated three-dimensional (3D) ultrasound technique for fetal intracranial measurements compared with manual acquisition. METHODS: This was a prospective observational study of patients presenting for routine anatomical survey between 18 + 0 and 22 + 6 weeks' gestation. After providing informed consent, each patient underwent two consecutive ultrasound examinations of the fetal head, one by a sonographer and one by a physician. Each operator obtained manual measurements of the biparietal diameter (BPD), head circumference (HC), transcerebellar diameter (TCD), cisterna magna (CM) and posterior horn of the lateral ventricle (Vp), followed by automated measurements of these structures using an artificial intelligence-based tool, SonoCNS® Fetal Brain. Both operators repeated the automated approach until all five measurements were obtained in a single sweep, up to a maximum of three attempts. The accuracy of automated measurements was compared with that of manual measurements using intraclass correlation coefficients (ICC) by operator type, accounting for patient and ultrasound characteristics. RESULTS: One hundred and forty-three women were enrolled in the study. Median body mass index was 24.0 kg/m2 (interquartile range (IQR), 22.5-26.8 kg/m2 ) and median subcutaneous thickness was 1.6 cm (IQR, 1.3-2.0 cm). Fifteen (10%) patients had at least one prior Cesarean delivery, 17 (12%) had other abdominal surgery and 78 (55%) had an anterior placenta. Successful acquisition of the automated measurements was achieved on the first, second and third attempts in 70%, 22% and 3% of patients, respectively, by sonographers and in 76%, 16% and 3% of cases, respectively, by physicians. The automated algorithm was not able to identify and measure all five structures correctly in six (4%) and seven (5%) patients scanned by the sonographers and physicians, respectively. The ICCs reflected good reliability (0.80-0.88) of the automated compared with the manual approach for BPD and HC and poor to moderate reliability (0.23-0.50) for TCD, CM and Vp. Fetal lie, head position, placental location, maternal subcutaneous thickness and prior Cesarean section were not associated with the success or accuracy of the automated technique. CONCLUSIONS: Automated 3D ultrasound imaging of the fetal head using SonoCNS reliably identified and measured BPD and HC but was less consistent in accurately identifying and measuring TCD, CM and Vp. While these results are encouraging, further optimization of the automated technology is necessary prior to incorporation of the technique into routine sonographic protocols. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Biometría/métodos , Feto/diagnóstico por imagen , Cabeza/diagnóstico por imagen , Imagenología Tridimensional/métodos , Ultrasonografía Prenatal/métodos , Adulto , Inteligencia Artificial , Femenino , Feto/embriología , Edad Gestacional , Cabeza/embriología , Humanos , Embarazo , Estudios Prospectivos , Reproducibilidad de los Resultados
2.
Malays J Pathol ; 40(2): 161-167, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30173234

RESUMEN

Primary bone lymphoma (PBL) is an uncommon type of extranodal lymphoma involvement. An anaplastic large-cell lymphoma (ALCL) is an extremely rare type of PBL, and it remains unclear whether ALCLs that primarily involve the bone exhibit favourable or unfavourable biological behaviour, and whether they are similar to ALCLs in general, or not. We reported a case of ALK-positive ALCL with primary bone involvement, and reviewed the clinicopathological features of 22 previously reported cases. An ALCL with primary bone involvement mostly affects younger patients with a preponderant towards the involvement of axial-bone. The prognosis of an ALCL that primarily involves bone is unfavourable, compared with PBL generally. The ALK-positive ALCLs in PBLs had less decedents than the ALK-negative ALCLs with a statistical non-significance (p=0.198).


Asunto(s)
Neoplasias Óseas/patología , Linfoma Anaplásico de Células Grandes/patología , Adulto , Quinasa de Linfoma Anaplásico/biosíntesis , Humanos , Masculino
3.
J Evol Biol ; 30(4): 839-847, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28187229

RESUMEN

Recent theory predicts that the magnitude of sexual antagonism should depend on how well populations are adapted to their environment. We tested this idea experimentally by comparing intersexual genetic correlations for adult survival in pedigreed populations of southern field crickets (Gryllus bimaculatus) raised on naturally balanced (free-choice) vs. imbalanced (protein-deprived) diets. We tested for (1) sex differences in nutritional intake and preference, (2) sex-specific effects of protein deprivation on survival and (3) diet dependence of the level of sexual antagonism. Adult males and females consumed a similar amount of protein, but protein deprivation decreased male survival but not female survival. Protein deprivation appeared to decrease the degree of sexual antagonism as intersexual genetic correlations were significantly lower than 1 only for the complementary free-choice diet group but close to 1 for the protein-deficient diet group. Our findings thereby implied that variation in nutritional environments can alter the magnitude of sexual antagonism. This research represents an important step towards understanding the relationship between sexual antagonism and adaptation in heterogeneous environments.


Asunto(s)
Dieta , Gryllidae/fisiología , Conducta Sexual Animal , Animales , Femenino , Humanos , Masculino , Caracteres Sexuales , Conducta Sexual
4.
Mol Hum Reprod ; 20(7): 701-8, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24723465

RESUMEN

There has been growing interest in the role of viral infections and their association with adverse pregnancy outcomes. However, little is known about the impact viral infections have on the fetal membranes (FM). Toll-like receptors (TLR) are thought to play a role in infection-associated inflammation at the maternal-fetal interface. Therefore, the objective of this study was to characterize the cytokine profile and antiviral response in human FMs exposed to viral dsRNA, which activates TLR3, and viral ssRNA, which activates TLR8; and to determine the mechanisms involved. The viral dsRNA analog, Poly(I:C), induced up-regulated secretion of MIP-1α, MIP-1ß, RANTES and TNF-α, and down-regulated interleukin (IL)-2 and VEGF secretion. In contrast, viral ssRNA induced a broader panel of cytokines in the FMs by up-regulating the secretion of IL-1ß, IL-2, IL-6, G-CSF, MCP-1, MIP-1α, MIP-1ß, RANTES, TNF-α and GRO-α. Using inhibitory peptides against TLR adapter proteins, FM secretion of MIP-1ß and RANTES in response to Poly(I:C) was MyD88 dependent; MIP-1α secretion was dependent on MyD88 and TRIF; and TNF-α production was independent of MyD88 and TRIF. Viral ssRNA-induced FM secretion of IL-1ß, IL-2, IL-6, G-CSF, MIP-1α, RANTES and GRO-α was dependent on MyD88 and TRIF; MIP-1ß was dependent upon TRIF, but not MyD88; and TNF-α and MCP-1 secretion was dependent on neither. Poly(I:C), but not ssRNA, induced an FM antiviral response by up-regulating the expression of IFNß, myxovirus-resistance A, 2',5'-oligoadenylate synthetase and apolipoprotein B mRNA-editing enzyme-catalytic polypeptide-like 3G. These findings demonstrate that human FMs respond to two viral signatures by generating distinct inflammatory cytokine/chemokine profiles and antiviral responses through different mechanisms.


Asunto(s)
Citocinas/metabolismo , Membranas Extraembrionarias/efectos de los fármacos , Poli I-C/farmacología , ARN Bicatenario/farmacología , ARN Viral/farmacología , Membranas Extraembrionarias/metabolismo , Femenino , Humanos , Embarazo , Regulación hacia Arriba/efectos de los fármacos
5.
J Evol Biol ; 26(10): 2260-70, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23980636

RESUMEN

Correlated suites of behaviours, or behavioural syndromes, appear to be widespread, and yet few studies have explored how they arise and are maintained. One possibility holds that correlational selection can generate and maintain behavioural syndrome if certain behavioural combinations enjoy greater fitness than other combinations. Here we test this correlational selection hypothesis by comparing behavioural syndrome structure with a multivariate fitness surface based on reproductive success of male water striders. We measured the structure of a behavioural syndrome including dispersal ability, exploration behaviour, latency to remount and sex recognition sensitivity in males. We then measured the relationship between these behaviours and mating success in a range of sex ratio environments. Despite the presence of some significant correlational selection, behavioural syndrome structure was not associated with correlational selection on behaviours. Although we cannot conclusively reject the correlational selection hypothesis, our evidence suggests that correlational selection and resulting linkage disequilibrium might not be responsible for maintaining the strong correlations between behaviours. Instead, we suggest alternative ways in which this behavioural syndrome may have arisen and outline the need for physiological and quantitative genetic tests of these suggestions.


Asunto(s)
Conducta Animal/fisiología , Heterópteros/fisiología , Selección Genética , Distribución Animal , Animales , Femenino , Heterópteros/genética , Masculino , Razón de Masculinidad , Conducta Sexual Animal
6.
Ultrasound Obstet Gynecol ; 40(2): 158-64, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22511529

RESUMEN

OBJECTIVE: To determine whether prenatal myelomeningocele repair is a cost-effective strategy compared to postnatal repair. METHODS: Decision-analysis modeling was used to calculate the cumulative costs, effects and incremental cost-effectiveness ratio of prenatal myelomeningocele repair compared with postnatal repair in singleton gestations with a normal karyotype that were identified with myelomeningocele between T1 and S1. The model accounted for costs and quality-adjusted life years (QALYs) in three populations: (1) myelomeningocele patients; (2) mothers carrying myelomeningocele patients; and (3) possible future siblings of these patients. Sensitivity analysis was performed using one-way, two-way and Monte Carlo simulations. RESULTS: Prenatal myelomeningocele repair saves $ 2 066 778 per 100 cases repaired. Additionally, prenatal surgery results in 98 QALYs gained per 100 repairs with 42 fewer neonates requiring shunts and 21 fewer neonates requiring long-term medical care per 100 repairs. However, these benefits are coupled to 26 additional cases of uterine rupture or dehiscence and one additional case of neurologic deficits in future offspring per 100 repairs. Results were robust in sensitivity analysis. CONCLUSION: Prenatal myelomeningocele repair is cost effective and frequently cost saving compared with postnatal myelomeningocele repair despite the increased likelihood of maternal and future pregnancy complications associated with prenatal surgery.


Asunto(s)
Costos de la Atención en Salud/estadística & datos numéricos , Meningomielocele/cirugía , Procedimientos Quirúrgicos Obstétricos/economía , Análisis Costo-Beneficio , Técnicas de Apoyo para la Decisión , Femenino , Humanos , Recién Nacido , Meningomielocele/economía , Embarazo , Factores de Tiempo
7.
Ultrasound Obstet Gynecol ; 38(1): 32-7, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21157771

RESUMEN

OBJECTIVE: To determine whether routine measurement of second-trimester transvaginal cervical length by ultrasound in low-risk singleton pregnancies is a cost-effective strategy. METHODS: We developed a decision analysis model to compare the cost-effectiveness of two strategies for identifying pregnancies at risk for preterm birth: (1) no routine cervical length screening and (2) a single routine transvaginal cervical length measurement at 18-24 weeks' gestation. In our model, women identified as being at increased risk (cervical length < 1.5 cm) for preterm birth would be offered daily vaginal progesterone supplementation. We assumed that vaginal progesterone reduces preterm birth at < 34 weeks' gestation by 45%. We also assumed that a decreased cervical length could result in additional costs (ultrasound scans, inpatient admission) without significantly improved neonatal outcomes. The main outcome measure was incremental cost-effectiveness ratio. RESULTS: Our model predicts that routine cervical-length screening is a dominant strategy when compared to routine care. For every 100,000 women screened, $12,119,947 can be potentially saved (in 2010 US dollars) and 423.9 quality-adjusted life-years could be gained. Additionally, we estimate that 22 cases of neonatal death or long-term neurologic deficits could be prevented per 100,000 women screened. Screening remained cost-effective but was no longer the dominant strategy when cervical-length ultrasound measurement costs exceeded $187 or when vaginal progesterone reduced delivery risk at < 34 weeks by less than 20%. CONCLUSION: In low-risk pregnancies, universal transvaginal cervical length ultrasound screening appears to be a cost-effective strategy under a wide range of clinical circumstances (varied preterm birth rates, predictive values of a shortened cervix and costs).


Asunto(s)
Medición de Longitud Cervical/métodos , Cuello del Útero/diagnóstico por imagen , Nacimiento Prematuro/diagnóstico por imagen , Cuello del Útero/anomalías , Análisis Costo-Beneficio , Árboles de Decisión , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Tamizaje Masivo/métodos , Embarazo , Segundo Trimestre del Embarazo , Nacimiento Prematuro/economía , Nacimiento Prematuro/prevención & control , Estados Unidos
8.
J Dent Res ; 100(1): 90-97, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32940141

RESUMEN

To investigate the characteristics and molecular events of dental pulp stem cells (DPSCs) for tissue regeneration with aging, we isolated and analyzed the stem cells from human exfoliated deciduous teeth (SHED) and permanent teeth of young (Y-DPSCs) and old (A-DPSCs) adults. Results showed that the stemness and osteogenic differentiation capacity of DPSCs decreased with aging. The RNA sequencing results showed that glycine, serine, and threonine metabolism was one of the most enriched gene clusters among SHED, Y-DPSCs, and A-DPSCs, according to analysis based on the Kyoto Encyclopedia of Genes and Genomes. The expression of serine metabolism-related enzymes phosphoserine aminotransferase 1 (PSAT1) and phosphoglycerate (PHGDH) decreased in A-DPSCs and provided less methyl donor S-adenosylmethionine (SAM) for DNA methylation, leading to the hypomethylation of the senescence marker p16 (CDNK2A). Furthermore, the proliferation and differentiation capacity of Y-DPSCs and SHED decreased after PHGDH siRNA treatment, which reduced the level of SAM. Convincingly, the ratios of PSAT1-, PHGDH-, or proliferating cell nuclear antigen-positive cells in the dental pulp of old permanent teeth were less than those in the dental pulp of deciduous teeth and young permanent teeth. In summary, the stemness and differentiation capacity of DPSCs decreased with aging. The decreased serine metabolism in A-DPSCs upregulated the expression of p16 via attenuating its DNA methylation, resulting in DPSC aging. Our finding indicated that serine metabolism and 1 carbon unit participated in stem cell aging, which provided new direction for stem cell aging study and intervention.


Asunto(s)
Pulpa Dental , Osteogénesis , Envejecimiento , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Senescencia Celular/genética , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Metilación de ADN , Humanos , Serina/genética , Diente Primario
9.
J Bacteriol ; 191(11): 3569-79, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19346311

RESUMEN

The facultative intracellular bacterial pathogen Brucella infects a wide range of warm-blooded land and marine vertebrates and causes brucellosis. Currently, there are nine recognized Brucella species based on host preferences and phenotypic differences. The availability of 10 different genomes consisting of two chromosomes and representing six of the species allowed for a detailed comparison among themselves and relatives in the order Rhizobiales. Phylogenomic analysis of ortholog families shows limited divergence but distinct radiations, producing four clades as follows: Brucella abortus-Brucella melitensis, Brucella suis-Brucella canis, Brucella ovis, and Brucella ceti. In addition, Brucella phylogeny does not appear to reflect the phylogeny of Brucella species' preferred hosts. About 4.6% of protein-coding genes seem to be pseudogenes, which is a relatively large fraction. Only B. suis 1330 appears to have an intact beta-ketoadipate pathway, responsible for utilization of plant-derived compounds. In contrast, this pathway in the other species is highly pseudogenized and consistent with the "domino theory" of gene death. There are distinct shared anomalous regions (SARs) found in both chromosomes as the result of horizontal gene transfer unique to Brucella and not shared with its closest relative Ochrobactrum, a soil bacterium, suggesting their acquisition occurred in spite of a predominantly intracellular lifestyle. In particular, SAR 2-5 appears to have been acquired by Brucella after it became intracellular. The SARs contain many genes, including those involved in O-polysaccharide synthesis and type IV secretion, which if mutated or absent significantly affect the ability of Brucella to survive intracellularly in the infected host.


Asunto(s)
Brucella/genética , Transferencia de Gen Horizontal/genética , Genoma Bacteriano/genética , Adipatos/metabolismo , Brucella/clasificación , Brucella/fisiología , Cromosomas Bacterianos/genética , Biología Computacional , Modelos Genéticos , Filogenia , Seudogenes/genética , Transducción de Señal/genética
10.
Minerva Ginecol ; 61(2): 127-39, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19255560

RESUMEN

Multiple gestations account for approximately 3% of all live births, but contribute to a disproportionate 15% of the overall perinatal mortality. Ultrasound evaluation of twin pregnancies serves an important role in surveillance, early detection, and invasive treatment of complications in twin pregnancies, including spontaneous abortion, abnormalities in placentation, preterm labor, growth restriction, congenital abnormalities, fetal demise, fetal mal-presentation, and twin-to-twin transfusion syndrome. A review of literature regarding the indications and use of ultrasound in twin pregnancy is presented.


Asunto(s)
Nacimiento Prematuro/diagnóstico por imagen , Nacimiento Prematuro/prevención & control , Diagnóstico Prenatal/métodos , Gemelos , Ultrasonografía Prenatal , Aborto Espontáneo/diagnóstico por imagen , Anomalías Congénitas/diagnóstico por imagen , Femenino , Enfermedades Fetales/diagnóstico por imagen , Enfermedades Fetales/prevención & control , Retardo del Crecimiento Fetal/diagnóstico por imagen , Transfusión Feto-Fetal/diagnóstico por imagen , Humanos , Presentación en Trabajo de Parto , Trabajo de Parto Prematuro/diagnóstico por imagen , Placenta/anomalías , Vigilancia de la Población , Embarazo , Resultado del Embarazo , Embarazo Múltiple , Nacimiento Prematuro/mortalidad , Medición de Riesgo , Gemelos Dicigóticos , Gemelos Monocigóticos
11.
Mol Cell Biol ; 18(5): 2721-8, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9566891

RESUMEN

The human BLM gene is a member of the Escherichia coli recQ helicase family, which includes the Saccharomyces cerevisiae SGS1 and human WRN genes. Defects in BLM are responsible for the human disease Bloom's syndrome, which is characterized in part by genomic instability and a high incidence of cancer. Here we describe the cloning of rad12+, which is the fission yeast homolog of BLM and is identical to the recently reported rhq1+ gene. We showed that rad12 null cells are sensitive to DNA damage induced by UV light and gamma radiation, as well as to the DNA synthesis inhibitor hydroxyurea. Overexpression of the wild-type rad12+ gene also leads to sensitivity to these agents and to defects associated with the loss of the S-phase and G2-phase checkpoint control. We showed genetically and biochemically that rad12+ acts upstream from rad9+, one of the fission yeast G2 checkpoint control genes, in regulating exit from the S-phase checkpoint. The physical chromosome segregation defects seen in rad12 null cells combined with the checkpoint regulation defect seen in the rad12+ overproducer implicate rad12+ as a key coupler of chromosomal integrity with cell cycle progression.


Asunto(s)
Proteínas de Ciclo Celular/genética , Ciclo Celular/genética , ADN Helicasas/genética , Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces/genética , Adenosina Trifosfatasas/genética , Reparación del ADN , Proteínas Fúngicas , RecQ Helicasas , Fase S , Homología de Secuencia de Aminoácido , Rayos Ultravioleta/efectos adversos
12.
Meat Sci ; 77(2): 257-63, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22061598

RESUMEN

Marbling score (MS) is the major qualitative trait that affects carcass quality in beef cattle. In this study, we examined the association between genetic polymorphisms of the titin-cap gene (TCAP) and carcass traits in Korean native cattle (also known as Hanwoo). By direct DNA sequencing in 24 unrelated Korean cattle, we identified five sequence variants in 1.2kb of TCAP. Among them, four common polymorphic sites were selected for genotyping in the beef cattle (n=437). Pair-wise linkage analysis with four polymorphisms showed strong linkage disequilibrium (LD), and three major haplotypes (freq.>0.1) were constructed. Statistical analysis revealed that polymorphisms in intron1 (g.346G>A) and exon2 (g.592-597CTGCAG[Leu-Gln]insdel) showed significant association with marbling score (P(cor.)=0.003 and 0.02, respectively). One haplotype, ht2[C-G-G-del], also showed significant association with MS (P(cor.)=0.0004). Our findings suggest that polymorphisms in TCAP might be among the important genetic factors involved in carcass quality in beef cattle.

13.
Front Biosci ; 11: 1077-89, 2006 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-16146798

RESUMEN

Experimental cryptorchidism is a common model for examining the expression and function of heat-sensitive spermatogenesis-related genes in testis. Previous studies have shown that germ cells in cryptorchid testis die mainly in an apoptotic way. The molecular mechanism, however, is still unclear. We have established unilateral cryptorchid monkey model (Cynomolgus Macaque) to identify possible molecules involved in the germ cell apoptosis. The degree of germ cell apoptosis, the morphology of the cryptorchid testis, and the changes in the serum concentration of FSH, LH and testosterone after cryptorchid surgery were analyzed. Sertoli cell marker molecule vimentin, the orphan receptor LRH-1, as well as the mitochondria-related protein HSP60 and Bcl-2 were examined. Our results showed that the weight of the cryptorchid testis decreased in a time-dependent manner started from day 7 after the surgery, while the weight of the scrotal testis had no obvious change. HE staining showed that from day 5, some germ cells were detached from the epithelium. A massive degeneration of the seminiferous epithelium characteristic of epithelial structural disorganization and the formation of multinucleated giant cells as well as vacuoles was observed on day 10 and 15. The cryptorchidism induced a marked germ cell apoptosis on day 3 after the operation, reaching a peak level on day 7.


Asunto(s)
Apoptosis , Criptorquidismo/patología , Células Germinativas/patología , Animales , Western Blotting , Chaperonina 60/biosíntesis , Fragmentación del ADN , Proteínas de Unión al ADN/metabolismo , Modelos Animales de Enfermedad , Células Epiteliales/metabolismo , Hormona Folículo Estimulante/metabolismo , Células Germinativas/metabolismo , Células Gigantes/metabolismo , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Hormona Luteinizante/metabolismo , Macaca fascicularis , Masculino , Modelos Biológicos , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Radioinmunoensayo , Receptores Citoplasmáticos y Nucleares/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células de Sertoli/metabolismo , Testículo/metabolismo , Factores de Tiempo , Factores de Transcripción/metabolismo , Vimentina/biosíntesis
14.
Nucleic Acids Res ; 27(24): 4715-24, 1999 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-10572171

RESUMEN

The topoisomerase III gene ( top3 (+)) from Schizosaccharomyces pombe was isolated and a targeted gene disruption ( top3 :: kan (R)) was used to make a diploid strain heterozygous for top3 (+). The diploid was sporulated and the top3 :: kan (R)spores went through four to eight cell divisions before arresting as elongated, predominantly binucleated cells with incompletely segregated chromosomes. This demonstrates that top3 (+)is essential for vegetative growth in fission yeast. The aberrant chromosomal segregation seen in top3 :: kan (R)cells is unlike the 'cut' phenotype seen in mitosis-defective mutants and so we refer to this phenotype as 'torn'. A deletion mutant, rad12-hd ( rad12 is a homolog of Saccharomyces cerevisiae SGS1), partially suppressed the lethality of top3 mutants. A point mutant, rad12-K547I, which presumably eliminates helicase activity, also suppresses the lethality of top3 mutants, demonstrating that the lethality seen in top3 (-)cells is most likely caused by the helicase activity of Rad12. This double mutant grows very slowly and has much lower viability compared to rad12-hd top3 :: kan (R)cells, implying that the helicase activity of Rad12 is not the only cause of top3 (-)lethality. The low viability of rad12 (-) top3 (-)mutants compared with rad12 single mutants suggests that Top3 also functions independently of Rad12.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , ADN Helicasas/metabolismo , ADN-Topoisomerasas de Tipo I/genética , Genes Fúngicos , Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces/genética , Secuencia de Aminoácidos , Sustitución de Aminoácidos , División Celular , Clonación Molecular , ADN-Topoisomerasas de Tipo I/química , ADN-Topoisomerasas de Tipo I/metabolismo , Diploidia , Eliminación de Gen , Genes Esenciales , Genes Letales , Genotipo , Heterocigoto , Humanos , Mitosis , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Fenotipo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/enzimología , Saccharomyces cerevisiae/genética , Schizosaccharomyces/enzimología , Schizosaccharomyces/fisiología , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Esporas Fúngicas
15.
J Natl Cancer Inst ; 71(4): 841-7, 1983 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6413744

RESUMEN

Growth inhibition in the Chinese hamster cell line V79 and in the human lymphoid cell line Raji and induction of sister chromatid exchange(s) (SCE) in V79 cells after treatment with six anticancer drugs [harringtonine (HRT), homoharringtonine (HHRT), camptothecin (CPT), hydroxycamptothecin (HCPT), lycobetaine (LBT), and oxalysine (OXL)] developed in the People's Republic of China were studied. OXL is a new antibiotic; all other drugs are plant extracts. All drugs caused a dose-dependent growth inhibition in both cell types, as evidenced by decreases in plating efficiencies of V79 cells and in viable cell counts of Raji. However, the degree of inhibition differed widely among the drugs. HRT, HHRT, CPT, and HCPT were the most potent growth inhibitors, LBT was next, and OXL was the least effective inhibitor. SCE analyses were made in V79 cells treated with a drug in the presence or absence of the metabolic activation system S9 mixture (S9 mix), except for the HRT assay in which the S9 mix was not used. CPT, HCPT, and LBT induced a dose-dependent increase in SCE frequencies, while HRT, HHRT, and OXL caused no SCE induction at any dose level used. CPT was the most powerful SCE inducer. HCPT induced SCE but at a much reduced rate when compared to that of CPT. LBT was a weak SCE inducer; SCE induction was seen only in cultures treated with 40 micrograms or more LBT/ml. Addition of the S9 mix did not alter SCE frequencies, indicating that the drugs were direct-acting agents. HRT and HHRT were highly toxic, but they induced no increases in SCE frequency, indicating that cytotoxicity of a compound does not necessarily correlate with SCE induction.


Asunto(s)
Alcaloides/toxicidad , Alcaloides de Amaryllidaceae , Antibióticos Antineoplásicos/toxicidad , Antineoplásicos Fitogénicos/toxicidad , Camptotecina/análogos & derivados , División Celular/efectos de los fármacos , Intercambio Genético/efectos de los fármacos , Harringtoninas/toxicidad , Indolizinas , Serina/análogos & derivados , Intercambio de Cromátides Hermanas/efectos de los fármacos , Aminoácidos Dicarboxílicos , Animales , Línea Celular , China , Cricetinae , Cricetulus , Homoharringtonina , Humanos , Pulmón , Tejido Linfoide , Pruebas de Mutagenicidad , Serina/toxicidad
16.
Biochim Biophys Acta ; 429(3): 993-1005, 1976 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-131582

RESUMEN

The effects of several alkali metal cations on the relationship between steady state phospho-enzyme levels and initial velocity and equilibrium levels of [3H]-ouabain binding to (Na+ + K+)-ATPase (ATP phosphohydrolase EC 3.6.1.3.) were examined. Only Na+ increased both phospho-enzyme and [3H] ouabain binding levels above those observed in the presence of Mg2+ alone. While Na+ stimulated phosphorylation with an apparent Km of about 1 mM, its stimulation of [3H] ouabain binding was biphasic, the lower Km for stimulation corresponding to the Km for formation of phospho-enzyme. Among the other alkali metal cations, potassium, rubidium and lithium were at least eight times more effect in reducing phospho-enzyme levels than in reducing [3H] ouabain binding. This discrepancy is not due to the stability of the enzyme-ouabain complex, nor to any action on the rates of formation or dissociation of the enzyme-ouabain complex. The data thus suggest that [3H] ouabain interacts with the K+, Rb+ or Li+ -enzyme complexes. For Li+, this hypothesis is further supported by the observation that Li+ can cirectly increase the equilibrium level of [3H] ouabain binding to this enzyme under certain conditions.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Cationes Monovalentes/farmacología , Ouabaína/metabolismo , Animales , Encéfalo/enzimología , Cesio/farmacología , Cobayas , Riñón/enzimología , Cinética , Litio/farmacología , Magnesio/farmacología , Potasio/farmacología , Unión Proteica , Ratas , Rubidio/farmacología , Sodio/farmacología
17.
Malays Orthop J ; 9(1): 23-27, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28435591

RESUMEN

BACKGROUND: Monteggia fracture-dislocation is rare in children. Various reports attest to its rarity, while recording the many variant of this injury. It is, therefore, easy to miss the diagnosis in the absence of proper clinical examination and radiographs. CASE REPORT: This report highlights two rare variants of Monteggia fracture-dislocation seen in children. The first case was a 12-year old girl alleged to have fallen from a 15- feet tall tree and sustaining a combined type III Monteggia injury with ipsilateral Type II Salter-Harris injury of distal end radius with a metaphyseal fracture of the distal third of the ulna. The second case was a 13-year old who had sustained a closed fracture of atypical Type I Monteggia hybrid lesion, in a road traffic accident. CONCLUSION: This report highlights the rare variants of Monteggia fracture dislocation which could have been missed without proper clinical examinations and radiographs.

18.
Parkinsonism Relat Disord ; 21(7): 704-8, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25937616

RESUMEN

BACKGROUNDS: Leukoaraiosis may present with slowly progressive parkinsonism indistinguishable from primary degenerative parkinsonism. Both leukoaraiosis and degenerative parkinsonism are an age-related disorder. Thus, comorbidity is expected to be common in elderly patients with parkinsonism. However, no systematic study has been reported on the clinical features indicating concomitant nigrostriatal dopaminergic denervation (NDD) in parkinsonian patients with leukoaraiosis. METHODS: We performed [(18)F] FP-CIT positron emission tomography studies in 42 consecutive parkinsonian patients with diffuse leukoaraiosis, but no basal ganglia vascular lesions. RESULTS: Twenty (48%) of the 42 patients had coexisting NDD. Compared to parkinsonian patients with isolated leukoaraiosis, those with coexisting NDD more frequently had asymmetric onset. They had similar degree of parkinsonian motor deficits in the legs, but greater rigidity and resting tremor in the arms. Consequently, they had less prominent lower body parkinsonism. They more frequently showed favorable response to levodopa treatment. They had similar burden of regional and total leukoaraiosis. Among a variety of clinical variables and MRI findings, only asymmetric onset and more than 30% improvement in UPDRS motor score by levodopa treatment were valuable indicators of coexisting NDD. CONCLUSIONS: We would like to recommend dopaminergic functional imaging studies for all parkinsonian patients with leukoaraiosis. Further studies are needed to confirm sensitivity and specificity of asymmetric onset and good levodopa response for the prediction of coexisting NDD in a different group of parkinsonian patients with leukoaraiosis.


Asunto(s)
Radioisótopos de Flúor , Leucoaraiosis/diagnóstico por imagen , Leucoaraiosis/epidemiología , Trastornos Parkinsonianos/diagnóstico por imagen , Trastornos Parkinsonianos/epidemiología , Tomografía de Emisión de Positrones , Anciano , Anciano de 80 o más Años , Cuerpo Estriado/diagnóstico por imagen , Femenino , Humanos , Masculino , Tomografía de Emisión de Positrones/métodos , Sustancia Negra/diagnóstico por imagen
19.
Genome Announc ; 3(3)2015 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-25977434

RESUMEN

Here, we report the completed genome sequences for two non-O1/non-O139 Vibrio cholerae isolates. Each isolate has only a single chromosome, as opposed to the normal paradigm of two chromosomes found in all other V. cholerae isolates.

20.
Genome Announc ; 3(1)2015 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-25614562

RESUMEN

We report the genome sequence of Anaeromyxobacter sp. Fw109-5, isolated from nitrate- and uranium-contaminated subsurface sediment of the Oak Ridge Integrated Field-Scale Subsurface Research Challenge (IFC) site, Oak Ridge Reservation, TN. The bacterium's genome sequence will elucidate its physiological potential in subsurface sediments undergoing in situ uranium bioremediation and natural attenuation.

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