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2.
Phys Rev Lett ; 125(20): 202701, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33258618

RESUMO

Type-I x-ray bursts can reveal the properties of an accreting neutron star system when compared with astrophysics model calculations. However, model results are sensitive to a handful of uncertain nuclear reaction rates, such as ^{22}Mg(α,p). We report the first direct measurement of ^{22}Mg(α,p), performed with the Active Target Time Projection Chamber. The corresponding astrophysical reaction rate is orders of magnitude larger than determined from a previous indirect measurement in a broad temperature range. Our new measurement suggests a less-compact neutron star in the source GS1826-24.

3.
Phys Rev Lett ; 123(8): 082501, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31491233

RESUMO

The elusive ß^{-}p^{+} decay was observed in ^{11}Be by directly measuring the emitted protons and their energy distribution for the first time with the prototype Active Target Time Projection Chamber in an experiment performed at ISAC-TRIUMF. The measured ß^{-}p^{+} branching ratio is orders of magnitude larger than any previous theoretical model predicted. This can be explained by the presence of a narrow resonance in ^{11}B above the proton separation energy.

4.
Skin Res Technol ; 25(2): 124-128, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30030918

RESUMO

BACKGROUND: Car drivers are generally exposed to direct sunlight during commuting hours, which may lead to irreversible skin damage; however, topographical analysis for different facial areas has not been reported. METHODS: Facial areas were divided topographically into 11 areas based on esthetic units. We performed a preliminary study to identify the delivery pattern of solar energy on the face in the car during commuting time; subsequently, 15 drivers aged above 50 years were enrolled. Statistical evaluation was performed to investigate topographical differences between the left and right sides of the face and between sexes. RESULTS: The left side of the face was different from the right side for L*, a*, and b* on the infraorbital area and L* and b* on the temporal area. Differences were found for L*, a*, or b* between sexes on the central and right face, but not on the left. The left side had more severe hyperpigmentation and wrinkles than the right on average. CONCLUSION: The left facial area, especially the infraorbital and temporal areas, of Korean automobile commuters was vulnerable to sun damage. Therefore, automobile drivers should care about these areas while driving to prevent long-term effect from chronic solar damage.


Assuntos
Face/efeitos da radiação , Pele/efeitos da radiação , Luz Solar/efeitos adversos , Automóveis , Face/patologia , Feminino , Humanos , Hiperpigmentação/patologia , Masculino , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Pele/patologia , Envelhecimento da Pele/patologia , Meios de Transporte
5.
Phys Rev Lett ; 120(2): 022502, 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29376727

RESUMO

The g factor of the 56 ns half-life isomeric state in ^{128}Cs has been measured using the time-differential perturbed angular distribution method. This state is the bandhead of the positive-parity chiral rotational band, which emerges when an unpaired proton, an unpaired neutron hole, and an even-even core are coupled such that their angular momentum vectors are aplanar (chiral configuration). g-factor measurements can give important information on the relative orientation of the three angular momentum vectors. The measured g factor g=+0.59(1) shows that there is an important contribution of the core rotation in the total angular momentum of the isomeric state. Moreover, a quantitative theoretical analysis supports the conclusion that the three angular momentum vectors lie almost in one plane, which suggests that the chiral configuration in ^{128}Cs demonstrated in previous works by characteristic patterns of electromagnetic transitions appears only above some value of the total nuclear spin.

6.
Acta Neurol Scand ; 135(2): 204-210, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26932899

RESUMO

OBJECTIVES: Primary restless leg syndrome (RLS) and periodic limb movements in sleep (PLMS) frequently co-exist, obscuring the boundaries between the two conditions. In such instances, a study of secondary cases with focal lesions such as post-stroke RLS and PLMS (psRLS and psPLMS, respectively) can be helpful in identifying characteristics of the individual conditions. MATERIALS AND METHODS: Patients who had suffered strokes and who subsequently developed psRLS or psPLMS were recruited. To determine the overall features of psRLS/PLMS, historical cases were selected from the literature. All cases with either psRLS or psPLMS alone were further analyzed to elucidate the distinctive pathomechanisms of the two conditions. RESULTS: Six patients with either psRLS or psPLMS were recruited from our hospital; two patients had both conditions contemporaneously. The literature contains details on 30 cases of psRLS or psPLMS. The causative lesion was most frequently located in the pons. We found that psRLS was more often bilateral, and usually detected later in time. Lesions in both the pontine base and tegmentum (together) were associated with unilateral psPLMS, whereas lesions in the corona radiata and adjacent basal ganglia were associated with bilateral RLS. Lesions confined to the corona radiata resulted in either unilateral or bilateral RLS. CONCLUSIONS: The observed differences in the clinical and radiological features of psRLS and psPLMS suggest that the pathophysiologies of the two conditions are distinct. Further research is needed to understand the pathophysiologies of primary RLS and PLMS.


Assuntos
Síndrome da Mioclonia Noturna/fisiopatologia , Síndrome das Pernas Inquietas/fisiopatologia , Sono/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome da Mioclonia Noturna/diagnóstico por imagem , Síndrome da Mioclonia Noturna/epidemiologia , Polissonografia/tendências , Ponte/diagnóstico por imagem , Síndrome das Pernas Inquietas/diagnóstico por imagem , Síndrome das Pernas Inquietas/epidemiologia , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/epidemiologia
7.
J Exp Med ; 203(5): 1235-47, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16636132

RESUMO

Emerging evidence suggests that both human stem cells and mature stromal cells can play an important role in the development and growth of human malignancies. In contrast to these tumor-promoting properties, we observed that in an in vivo model of Kaposi's sarcoma (KS), intravenously (i.v.) injected human mesenchymal stem cells (MSCs) home to sites of tumorigenesis and potently inhibit tumor growth. We further show that human MSCs can inhibit the in vitro activation of the Akt protein kinase within some but not all tumor and primary cell lines. The inhibition of Akt activity requires the MSCs to make direct cell-cell contact and can be inhibited by a neutralizing antibody against E-cadherin. We further demonstrate that in vivo, Akt activation within KS cells is potently down-regulated in areas adjacent to MSC infiltration. Finally, the in vivo tumor-suppressive effects of MSCs correlates with their ability to inhibit target cell Akt activity, and KS tumors engineered to express a constitutively activated Akt construct are no longer sensitive to i.v. MSC administration. These results suggest that in contrast to other stem cells or normal stromal cells, MSCs possess intrinsic antineoplastic properties and that this stem cell population might be of particular utility for treating those human malignancies characterized by dysregulated Akt.


Assuntos
Efeito Enxerto vs Tumor/imunologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/imunologia , Sarcoma de Kaposi/imunologia , Animais , Modelos Animais de Doenças , Ativação Enzimática/imunologia , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , Proteína Oncogênica v-akt/imunologia , Sarcoma de Kaposi/patologia , Sarcoma de Kaposi/terapia , Células Estromais/imunologia , Células Estromais/transplante , Transplante Heterólogo , Células Tumorais Cultivadas
8.
Pharmacogenomics J ; 10(4): 364-74, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20368714

RESUMO

The discordance in results of independent genome-wide association studies (GWAS) indicates the potential for Type I and Type II errors. We assessed the repeatibility of current Affymetrix technologies that support GWAS. Reasonable reproducibility was observed for both raw intensity and the genotypes/copy number variants. We also assessed consistencies between different SNP arrays and between genotype calling algorithms. We observed that the inconsistency in genotypes was generally small at the specimen level. To further examine whether the differences from genotyping and genotype calling are possible sources of variation in GWAS results, an association analysis was applied to compare the associated SNPs. We observed that the inconsistency in genotypes not only propagated to the association analysis, but was amplified in the associated SNPs. Our studies show that inconsistencies between SNP arrays and between genotype calling algorithms are potential sources for the lack of reproducibility in GWAS results.


Assuntos
Estudo de Associação Genômica Ampla/estatística & dados numéricos , Genótipo , Haplótipos/genética , Algoritmos , DNA/genética , Interpretação Estatística de Dados , Dosagem de Genes , Humanos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Polimorfismo de Nucleotídeo Único , Reprodutibilidade dos Testes
9.
Science ; 202(4368): 635-7, 1978 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-17754039

RESUMO

A strain of Amoeba proteus has lost its ability to survive at temperatures above 26 degrees C as a result of becoming dependent on endosymbiotic bacteria that are psychrophile-like. The observed temperature sensitivity develops in fewer than 200 host cell generations (18 months of culture) after the host cells are experimentally infected with the symbionts.

10.
Regul Toxicol Pharmacol ; 53(1): 63-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19047007

RESUMO

This study investigated the potential adverse effects of 1,3-dichloro-2-propanol (1,3-DCP) on pregnant dams and the embryo-fetal development after maternal exposure on gestational days (GD) 6 through 19 in Sprague-Dawley rats. The test chemical was administered to pregnant rats by gavage at dose levels of 0, 10, 30, and 90mg/kg per day (n=10 for each group). All dams underwent Caesarean sections on GD 20, and their fetuses were examined for morphological abnormalities. Maternal toxicity was noted at 90mg/kg/day. Manifestations of toxicity included clinical signs of illness, lower body weight gain, decreased food intake, and increases in the weight of the adrenal glands and the liver. Developmental toxic effects including decreases in fetal body weight and increases in visceral and skeletal variations also occurred at the highest dose. At 30mg/kg, only a minimal maternal toxicity, including a decrease in maternal food intake and an increase in the liver weight, was observed. No adverse maternal or developmental effects were observed at 10mg/kg/day. These results revealed that a 14-day repeated oral dose of 1,3-DCP was minimally embryotoxic but not teratogenic at a maternal toxic dose (90mg/kg/day), and was not embryotoxic at a minimally maternal toxic dose (30mg/kg/day) in rats. Because the developmental toxicity of 1,3-DCP was observed only in the presence of maternal toxicity, it is concluded that the developmental findings observed in the present study are secondary effects to maternal toxicity. Under these experimental conditions, the no-observed-adverse-effect level of 1,3-DCP is considered to be 10mg/kg/day for dams and 30mg/kg/day for embryo-fetal development.


Assuntos
Desenvolvimento Fetal/efeitos dos fármacos , Exposição Materna , Mutagênicos/toxicidade , alfa-Cloridrina/análogos & derivados , Administração Oral , Animais , Relação Dose-Resposta a Droga , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Peso Fetal/efeitos dos fármacos , Masculino , Mutagênicos/administração & dosagem , Nível de Efeito Adverso não Observado , Tamanho do Órgão/efeitos dos fármacos , Gravidez , Ratos , Ratos Sprague-Dawley , Aumento de Peso/efeitos dos fármacos , alfa-Cloridrina/administração & dosagem , alfa-Cloridrina/toxicidade
11.
Artigo em Inglês | MEDLINE | ID: mdl-18200572

RESUMO

BACKGROUND: Recently, it was reported that the 4-week exposure of rats to a concrete building environment under cool temperatures (11.7-12.1 degrees C) had adverse effects on the general health parameters. This study examined the potential effects of concrete and hwangto building environments on pregnant dams and embryo-fetal development in Sprague-Dawley rats. METHODS: Groups of 10 mated females were exposed to polycarbonate (control), concrete, or hwangto cages from gestational days (GD) 0 to 20 under cool temperatures (11.9-12.5 degrees C). All the females underwent a caesarean section on GD 20, and their fetuses were examined for any morphological abnormalities. RESULTS: The temperatures in the cages were similar in all groups but the relative humidity in the concrete and hwangto groups were higher than in the control group. The concentration of volatile organic compounds in the hwangto group during the study period was lower than in the control group. In the concrete group, maternal effects manifested as an increase in the incidence of clinical signs, a lower body weight, and a decrease in the thymus and ovary weights. Developmental effects included increased post-implantation loss and decreased litter size. In contrast, in the hwangto group, there were no exposure-related adverse effects on the maternal and developmental parameters. CONCLUSIONS: Overall, the exposure of pregnant rats to a concrete building environment under cool temperatures has adverse effects on the clinical signs, body weight, organ weight, and embryo-fetal development. On the other hand, exposure to a hwangto building environment does not have any adverse effects on pregnant dams or on embryo-fetal development in rats.


Assuntos
Criação de Animais Domésticos , Materiais de Construção/toxicidade , Desenvolvimento Embrionário/fisiologia , Desenvolvimento Fetal/fisiologia , Abrigo para Animais , Poluentes Atmosféricos/análise , Animais , Feminino , Umidade , Masculino , Exposição Materna , Compostos Orgânicos/análise , Gravidez , Ratos , Ratos Sprague-Dawley , Organismos Livres de Patógenos Específicos
12.
Environ Technol ; 28(6): 701-11, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17624110

RESUMO

The usefulness of the electrical resistivity method for characterization of contaminated sites has been studied in many ways. The most commonly used device is a cone penetrometer that utilizes two or four electrodes to measure electrical resistivity (or conductivity) during a cone penetration test (CPT) along a vertical or horizontal alignment. This paper introduces a new miniature resistivity probe (MRP) that can potentially be deployed from a sampling platform to detect contaminant plumes prior to collecting soil samples. Following bench-scale tests aimed at quantifying the sensitivity of the MRP to various operating and environmental parameters, the response of the MRP in sandy soil containing various concentrations of tour heavy metals (Cu, Zn, Pb and Ni) and two hydrocarbons (phenol and gasoline) is evaluated. The test data revealed that the MRP has the potential to serve as an indexing tool for rapidly delineating contaminant plumes where heavy metals are present. The results for hydrocarbons were less conclusive, ranging from moderate ability to differentiate contaminated and non-contaminated soils for phenol to poor differentiation ability for gasoline.


Assuntos
Hidrocarbonetos/análise , Metais Pesados/análise , Calibragem , Miniaturização
13.
Water Sci Technol ; 54(3): 185-90, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17037151

RESUMO

The aim of this study was to evaluate the use of total coliforms (TC) and faecal coliforms (FC) using a membrane filtration method for precise monitoring of faecal pollution in Korean surface water. The samples were collected in Korea from both main rivers and their tributaries. Presumptive TC * FC were enumerated. The ratios of presumptive FC to TC were not constant, but varied widely, and TC were difficult to enumerate because of overgrowth by background colonies. For FC this was not the case. Seven hundred and three purified strains of presumptive TC * FC and their background colonies were biotyped using API 20E. Among 272 presumptive TC, non-faecal related species, Aeromonas hydrophila dominated (34.6%) and E. coli accounted for only 5.1%. In contrast, E. coli made up 89% of the 209 presumptive FC. Furthermore, of 164 background colonies on Endo Agar LES, 54.9% was A. hydrophila, while background colonies on m-FC Agar were few (58 strains), and despite their atypical colony appearance, most of them were biotyped as enteric bacteria. These results reveal that the detection of FC rather than TC using m-FC Agar is more appropriate for faecal pollution monitoring in eutrophicated surface water located in a temperate region.


Assuntos
Enterobacteriaceae/isolamento & purificação , Fezes/microbiologia , Microbiologia da Água , Enterobacteriaceae/classificação , Especificidade da Espécie
14.
J Hum Hypertens ; 30(5): 315-21, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26155994

RESUMO

Reports detailing the response of hypertensive patients to renal denervation (RDN) in Asian patients are limited. We evaluated 6- and 12-month outcomes after RDN in an Asian population and compared outcomes to a primarily Caucasian population. The Global SYMPLICITY Registry (GSR) is a prospective, all-comer, worldwide registry that evaluates the safety and effectiveness of RDN and includes the Korean registry substudy (GSR Korea) and a Caucasian subset (GSR Caucasian). Given differences in baseline characteristics among GSR Korea (n=93) as compared with GSR Caucasian (n=169) patients, including lower baseline office systolic blood pressure (SBP), lower body mass index and differences in medications, propensity score adjustment was performed when comparing the change in SBP between subsets. The 6- and 12-month change in SBP in GSR Korea was -19.4±17.2 and -27.2±18.1 mm Hg, respectively (P<0.001 for both vs baseline). GSR Caucasian had a SBP change similar to GSR Korea at 6 months (-20.9±21.4 mm Hg, unadjusted P=0.547, adjusted P=0.998), whereas at 12 months the change was significantly less pronounced (-20.1±23.9 mm Hg, unadjusted P=0.004, adjusted P=0.002). There were no protocol-defined procedure-related adverse events and no chronic adverse events associated with the device in an Asian population. RDN provided a significant reduction in 6- and 12-month office SBP among Asian patients, with a favorable safety profile. The 12-month SBP reduction was larger than that observed in Caucasian patients.


Assuntos
Ablação por Cateter/estatística & dados numéricos , Denervação/estatística & dados numéricos , Hipertensão/cirurgia , Sistema de Registros , Artéria Renal/inervação , Adulto , Idoso , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Feminino , Humanos , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
15.
J Am Coll Cardiol ; 38(5): 1409-15, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11691516

RESUMO

OBJECTIVES: We assessed the effects of estrogen on vascular dilatory and other homeostatic functions potentially affected by nitric oxide (NO)-potentiating properties in type II diabetic postmenopausal women. BACKGROUND: There is a higher cardiovascular risk in diabetic women than in nondiabetic women. This would suggest that women with diabetes do not have the cardioprotection associated with estrogen. METHODS: We administered placebo or conjugated equine estrogen, 0.625 mg/day for 8 weeks, to 20 type II diabetic postmenopausal women in a randomized, double-blinded, placebo-controlled, cross-over design. RESULTS: Compared with placebo, estrogen tended to lower low-density lipoprotein (LDL) cholesterol levels by 15 +/- 23% (p = 0.007) and increase high-density lipoprotein (HDL) cholesterol levels by 8 +/- 16% (p = 0.034). Thus, the ratio of LDL to HDL cholesterol levels significantly decreased with estrogen, by 20 +/- 24%, as compared with placebo (p = 0.001). Compared with placebo, estrogen tended to increase triglyceride levels by 16 +/- 48% and lower glycosylated hemoglobin levels by 3 +/- 13% (p = 0.295 and p = 0.199, respectively). However, estrogen did not significantly improve the percent flow-mediated dilatory response to hyperemia (17 +/- 75% vs. placebo; p = 0.501). The statistical power to accept our observation was 81.5%. Compared with placebo, estrogen did not significantly change E-selectin, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, monocyte chemoattractant protein-1 or matrix metalloproteinase-9 levels. Compared with placebo, estrogen tended to decrease tissue factor antigen and increase tissue factor activity levels by 7 +/- 46% and 5 +/- 34%, respectively (p = 0.321 and p = 0.117, respectively) and lower plasminogen activator inhibitor-1 levels by 16 +/- 31% (p = 0.043). CONCLUSIONS: The effects of estrogen on endothelial, vascular dilatory and other homeostatic functions were less apparent in type II diabetic postmenopausal women, despite the beneficial effects of estrogen on lipoprotein levels.


Assuntos
Artéria Braquial/efeitos dos fármacos , Artéria Braquial/fisiologia , Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Estrogênios Conjugados (USP)/farmacologia , Óxido Nítrico/fisiologia , Pós-Menopausa/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/fisiopatologia , Quimiocina CCL2/fisiologia , HDL-Colesterol/sangue , HDL-Colesterol/efeitos dos fármacos , LDL-Colesterol/sangue , LDL-Colesterol/efeitos dos fármacos , Estudos Cross-Over , Método Duplo-Cego , Sinergismo Farmacológico , Selectina E/efeitos dos fármacos , Feminino , Fibrinólise/efeitos dos fármacos , Hemoglobinas Glicadas/efeitos dos fármacos , Hemoglobinas Glicadas/metabolismo , Hemostasia/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Humanos , Molécula 1 de Adesão Intercelular/efeitos dos fármacos , Metaloproteinase 9 da Matriz/efeitos dos fármacos , Pessoa de Meia-Idade , Inibidor 1 de Ativador de Plasminogênio/fisiologia , Tromboplastina/efeitos dos fármacos , Triglicerídeos/sangue , Molécula 1 de Adesão de Célula Vascular/efeitos dos fármacos
16.
Opt Express ; 13(20): 8256-62, 2005 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-19498855

RESUMO

A novel differential mode delay (DMD) measurement technique for a multimode optical fiber based on optical frequency domain reflectometry (OFDR) has been proposed. We have obtained a high-resolution DMD value of 0.054 ps/m for a commercial multimode optical fiber with length of 50 m by using a modified OFDR in a Mach-Zehnder interferometer structure with a tunable external cavity laser and a Mach-Zehnder interferometer instead of Michelson interferometer. We have also compared the OFDR measurement results with those obtained using a traditional time-domain measurement method. DMD resolution with our proposed OFDR technique is more than an order of magnitude better than a result obtainable with a conventional time-domain method.

17.
Opt Express ; 13(11): 4005-11, 2005 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-19495311

RESUMO

A novel mode analysis method and differential mode delay (DMD) measurement technique for a multimode optical fiber based on optical frequency domain reflectometry has been proposed for the first time. We have used a conventional OFDR with a tunable external cavity laser and a Michelson interferometer. A few-mode optical multimode fiber was prepared to test our proposed measurement technique. We have also compared the OFDR measurement results with those obtained using a traditional time-domain measurement method.

18.
J Neuroendocrinol ; 27(2): 100-10, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25496429

RESUMO

Prenatal exposure of the female ovine foetus to excess testosterone leads to neuroendocrine disruptions in adulthood, as demonstrated by defects in responsiveness with respect to the ability of gonadal steroids to regulate gonadotrophin-releasing hormone (GnRH) secretion. In the ewe, neurones of the arcuate nucleus (ARC), which co-expresses kisspeptin, neurokinin B (NKB) and dynorphin (termed KNDy cells), play a key role in steroid feedback control of GnRH and show altered peptide expression after prenatal testosterone treatment. KNDy cells also co-localise NKB receptors (NK3R), and it has been proposed that NKB may act as an autoregulatory transmitter in KNDy cells where it participates in the mechanisms underlying steroid negative-feedback. In addition, recent evidence suggests that NKB/NK3R signalling may be involved in the positive-feedback actions of oestradiol leading to the GnRH/luteinising hormone (LH) surge in the ewe. Thus, we hypothesise that decreased expression of NK3R in KNDy cells may be present in the brains of prenatal testosterone-treated animals, potentially contributing to reproductive defects. Using single- and dual-label immunohistochemistry we found NK3R-positive cells in diverse areas of the hypothalamus; however, after prenatal testosterone treatment, decreased numbers of NK3R immunoreactive (-IR) cells were seen only in the ARC. Moreover, dual-label confocal analyses revealed a significant decrease in the percentage of KNDy cells (using kisspeptin as a marker) that co-localised NK3R. To investigate how NKB ultimately affects GnRH secretion in the ewe, we examined GnRH neurones in the preoptic area (POA) and mediobasal hypothalamus (MBH) for the presence of NK3R. Although, consistent with earlier findings, we found no instances of NK3R co-localisation in GnRH neurones in either the POA or MBH; in addition, > 70% GnRH neurones in both areas were contacted by NK3R-IR presynaptic terminals suggesting that, in addition to its role at KNDy cell bodies, NKB may regulate GnRH neurones by presynaptic actions. In summary, the finding of decreased NK3R within KNDy cells in prenatal testosterone-treated sheep complements previous observations of decreased NKB and dynorphin in the same population, and may contribute to deficits in the feedback control of GnRH/LH secretion in this animal model.


Assuntos
Núcleo Arqueado do Hipotálamo/metabolismo , Feto/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Receptores da Neurocinina-3/imunologia , Testosterona/metabolismo , Animais , Núcleo Arqueado do Hipotálamo/citologia , Dinorfinas/metabolismo , Feminino , Kisspeptinas/metabolismo , Neurocinina B/metabolismo , Gravidez , Ovinos , Testosterona/farmacologia
19.
Bone Joint J ; 97-B(12): 1726-31, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26637691

RESUMO

The traditional techniques involving an oblique tunnel or triangular wedge resection to approach a central or mixed-type physeal bar are hindered by poor visualisation of the bar. This may be overcome by a complete transverse osteotomy at the metaphysis near the growth plate or a direct vertical approach to the bar. Ilizarov external fixation using small wires allows firm fixation of the short physis-bearing fragment, and can also correct an associated angular deformity and permit limb lengthening. We accurately approached and successfully excised ten central- or mixed-type bars; six in the distal femur, two in the proximal tibia and two in the distal tibia, without damaging the uninvolved physis, and corrected the associated angular deformity and leg-length discrepancy. Callus formation was slightly delayed because of periosteal elevation and stretching during resection of the bar. The resultant resection of the bar was satisfactory in seven patients and fair in three as assessed using a by a modified Williamson-Staheli classification.


Assuntos
Epífises/cirurgia , Fêmur/cirurgia , Lâmina de Crescimento/cirurgia , Técnica de Ilizarov , Desigualdade de Membros Inferiores/cirurgia , Osteotomia/métodos , Tíbia/cirurgia , Adolescente , Fios Ortopédicos , Criança , Feminino , Humanos , Masculino
20.
Bone Joint J ; 97-B(11): 1525-32, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26530656

RESUMO

The purpose of this study was to evaluate the change in sagittal tibiotalar alignment after total ankle arthroplasty (TAA) for osteoarthritis and to investigate factors affecting the restoration of alignment. This retrospective study included 119 patients (120 ankles) who underwent three component TAA using the Hintegra prosthesis. A total of 63 ankles had anterior displacement of the talus before surgery (group A), 49 had alignment in the normal range (group B), and eight had posterior displacement of the talus (group C). Ankles in group A were further sub-divided into those in whom normal alignment was restored following TAA (41 ankles) and those with persistent displacement (22 ankles). Radiographic and clinical results were assessed. Pre-operatively, the alignment in group A was significantly more varus than that in group B, and the posterior slope of the tibial plafond was greater (p < 0.01 in both cases). The posterior slope of the tibial component was strongly associated with restoration of alignment: ankles in which the alignment was restored had significantly less posterior slope (p < 0.001). An anteriorly translated talus was restored to a normal position after TAA in most patients. We suggest that surgeons performing TAA using the Hintegra prosthesis should aim to insert the tibial component at close to 90° relative to the axis of the tibia, hence reducing posterior soft-tissue tension and allowing restoration of normal tibiotalar alignment following surgery.


Assuntos
Artroplastia de Substituição do Tornozelo/métodos , Deformidades Articulares Adquiridas/cirurgia , Osteoartrite/cirurgia , Tálus/patologia , Tíbia/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/patologia , Articulação do Tornozelo/fisiopatologia , Articulação do Tornozelo/cirurgia , Feminino , Humanos , Deformidades Articulares Adquiridas/diagnóstico por imagem , Deformidades Articulares Adquiridas/etiologia , Deformidades Articulares Adquiridas/patologia , Prótese Articular , Masculino , Pessoa de Meia-Idade , Osteoartrite/complicações , Osteoartrite/diagnóstico por imagem , Osteoartrite/patologia , Radiografia , Amplitude de Movimento Articular , Estudos Retrospectivos , Tálus/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Resultado do Tratamento
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