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1.
Rev Sci Instrum ; 94(3): 033511, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37012804

RESUMO

High-power, short-pulse laser-driven fast electrons can rapidly heat and ionize a high-density target before it hydrodynamically expands. The transport of such electrons within a solid target has been studied using two-dimensional (2D) imaging of electron-induced Kα radiation. However, it is currently limited to no or picosecond scale temporal resolutions. Here, we demonstrate femtosecond time-resolved 2D imaging of fast electron transport in a solid copper foil using the SACLA x-ray free electron laser (XFEL). An unfocused collimated x-ray beam produced transmission images with sub-micron and ∼10 fs resolutions. The XFEL beam, tuned to its photon energy slightly above the Cu K-edge, enabled 2D imaging of transmission changes induced by electron isochoric heating. Time-resolved measurements obtained by varying the time delay between the x-ray probe and the optical laser show that the signature of the electron-heated region expands at ∼25% of the speed of light in a picosecond duration. Time-integrated Cu Kα images support the electron energy and propagation distance observed with the transmission imaging. The x-ray near-edge transmission imaging with a tunable XFEL beam could be broadly applicable for imaging isochorically heated targets by laser-driven relativistic electrons, energetic protons, or an intense x-ray beam.

2.
Res Vet Sci ; 130: 48-51, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32143083

RESUMO

Ceramides (CERs) in the stratum corneum (SC) are known to play a crucial role in determining skin barrier function in dogs. We aimed to develop an in vitro culture system that synthesized epidermal CER classes to better understand the synthesis of CER classes in canine SC-. Canine keratinocyte cells (MSCEK) at appropriate confluency were incubated with high Ca2+ (1.8 mM CaCl2) supplemented serum-free medium. Eight days post Ca2+ application, the surface of cultured MSCEK was broadly stained with anti-loricrin antibody implying that the keratinocytes had stratified into stratum granulosum. MSCEK cells synthesized heterogenous epidermal CERs, similar to those seen during the stratification of canine keratinocytes. CER fractions obtained from MSCEK cells were comparable to those from canine SC, including CER[EOS] (combination of ω-hydroxy fatty acids and sphingosines), CER[NP] (combination of non-hydroxy fatty acids and phytosphingosines), and CER[EOP] (combination of ω-hydroxy fatty acids and phytosphingosines), all of which are lowered in the SC during canine atopic dermatitis. Thus, the present study provides a simple culture system as a tool for in-depth analysis of CER production in canine keratinocytes.


Assuntos
Técnicas de Cultura de Células/veterinária , Ceramidas/síntese química , Queratinócitos/química , Animais , Técnicas de Cultura de Células/métodos , Cães , Epiderme/química
4.
Sci Rep ; 8(1): 15847, 2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-30367130

RESUMO

The nitrogen-vacancy (NV) centre in diamond is a promising candidate for quantum computing applications and magnetic sensing applications, because it is an atomic-scale defect with stable coherence time (T2) and reliable accessibility at room temperature. We demonstrated a method for improving the NV spin properties (the full width half maximum (FWHM) value of the magnetic resonance spectrum and T2) through a near-field (NF) etching method under ambient conditions. The NF etching method, based on a He-Cd ultraviolet laser (325 nm), which is longer than the absorption edge of the oxygen molecule, enabled selective removal of defects on the nanodiamond surface. We observed a decrease in the FWHM value close to 15% and an increase in T2 close to 25%. Since our technique can be easily reproduced, a wide range of NV centre applications could be improved, especially magnetic sensing applications. Our results are especially attractive, because they have been obtained under ambient conditions and only require a light source with wavelength slightly above the O2 absorption edge.

5.
J Assist Reprod Genet ; 35(5): 899-905, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29357025

RESUMO

PURPOSE: In human oocytes, sERCs are one of the dysmorphic phenotypes that have been reported. Significantly reduced pregnancy rates and a comparatively higher number of abnormities in live births appear to be associated with the presence of sERCs in oocytes. However, some reports have shown that healthy babies can be born, without any reduced pregnancy rates, from oocytes observed to contain sERCs. Thus, the clinical and scientific significance of oocytes that harbor sERCs remains controversial. METHODS: The presence of sERCs was evaluated using a time-lapse system while studying the dynamic changes within oocytes and embryos. Logistic regression analysis was carried out to explore the independent variables for meiotic and mitotic cleavage failure.. RESULTS: The incidence of mitotic cleavage failure and the incidence of meiotic cleavage failure during the second polar body extrusion in oocytes with sERCs were found to be significantly higher than that in oocytes without sERCs. Furthermore, ICSI was found to have a greater frequency of meiotic failure than IVF. CONCLUSIONS: In cases of cleavage failure, an embryonic cell could become tetraploid and may induce abnormal chromosomal configurations. Some cells exposed to cleavage failure may become trophectoderm cells and form placental abnormalities. Even if they develop into trophectoderm cells, the ICM can be susceptible to further cleavage failure and may in turn cause further aneuploidy. For these reasons, it is important to monitor pregnancies and births derived from oocytes that contained sERCs.


Assuntos
Retículo Endoplasmático Liso/patologia , Fertilização in vitro/métodos , Oócitos/patologia , Adulto , Feminino , Humanos , Meiose , Injeções de Esperma Intracitoplásmicas/métodos , Imagem com Lapso de Tempo , Resultado do Tratamento
6.
Rev Sci Instrum ; 89(12): 125007, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30599584

RESUMO

Ultimate sensitivity for quantum magnetometry using nitrogen-vacancy (NV) centers in a diamond is limited by a number of NV centers and coherence time. Microwave irradiation with a high and homogeneous power density for a large detection volume is necessary to achieve a highly sensitive magnetometer. Here, we demonstrate a microwave resonator to enhance the power density of the microwave field and an optical system with a detection volume of 1.4 × 10-3 mm3. The strong microwave field enables us to achieve 48 ns Rabi oscillation which is sufficiently faster than the phase relaxation time of NV centers. This system combined with a decoupling pulse sequence, XY16, extends the spin coherence time (T 2) up to 27 times longer than that with a spin echo method. Consequently, we obtained an AC magnetic field sensitivity of 10.8 pt/ Hz using the dynamical decoupling pulse sequence.

7.
Orthod Craniofac Res ; 20(2): 95-101, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28414873

RESUMO

OBJECTIVES: To examine the influence of negative pressure of the pharyngeal airway on mandibular retraction during inspiration in children with nasal obstruction using the computational fluid dynamics (CFD) method. SETTING AND SAMPLE POPULATION: Sixty-two children were divided into Classes I, II (mandibular retrusion) and III (mandibular protrusion) malocclusion groups. MATERIAL AND METHODS: Cone-beam computed tomography data were used to reconstruct three-dimensional shapes of the nasal and pharyngeal airways. Airflow pressure was simulated using CFD to calculate nasal resistance and pharyngeal airway pressure during inspiration and expiration. RESULTS: Nasal resistance of the Class II group was significantly higher than that of the other two groups, and oropharyngeal airway inspiration pressure in the Class II (-247.64 Pa) group was larger than that in the Class I (-43.51 Pa) and Class III (-31.81 Pa) groups (P<.001). The oropharyngeal airway inspiration-expiration pressure difference in the Class II (-27.38 Pa) group was larger than that in the Class I (-5.17 Pa) and Class III (0.68 Pa) groups (P=.006). CONCLUSION: Large negative inspiratory pharyngeal airway pressure due to nasal obstruction in children with Class II malocclusion may be related to their retrognathia.


Assuntos
Resistência das Vias Respiratórias , Tomografia Computadorizada de Feixe Cônico , Má Oclusão Classe II de Angle/diagnóstico por imagem , Má Oclusão Classe II de Angle/fisiopatologia , Obstrução Nasal/diagnóstico por imagem , Obstrução Nasal/fisiopatologia , Faringe/anormalidades , Faringe/diagnóstico por imagem , Criança , Feminino , Humanos , Masculino , Pressão
8.
Cryo Letters ; 38(1): 1-6, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28376134

RESUMO

BACKGROUND: In the vitrification of embryos, dimethyl sulfoxide (DMSO) is one of the most effective cryoprotectant agents (CPAs), but cytotoxic effects of DMSO on embryos are well known. Carboxylated poly-L-lysine (CPLL) has been identified as an effective cryoprotectant of cultured cell lines and mammalian oocytes. OBJECTIVE: To evaluate the efficacy and safety of CPLL as a CPA for developmental stage embryos. MATERIALS AND METHODS: Mouse 8-cell embryos and blastocysts were vitrified with ethylene glycol (EG), DMSO/EG, or CPLL/EG and the developmental potency assessed in vitro. RESULTS: In 8-cell embryos, there were no differences between the levels of survival and developmental progress into the blastocyst stage in each solution. At the blastocyst stage, the proportion of dead cells was significantly higher in the EG compared with other solutions. In contrast, there were no differences between the DMSO/EG and CPLL/EG. CONCLUSION: These results indicate that CPLL can be used as a replacement for DMSO in the vitrification of mouse embryos.


Assuntos
Blastocisto/efeitos dos fármacos , Criopreservação/métodos , Crioprotetores/farmacologia , Desenvolvimento Embrionário/efeitos dos fármacos , Polilisina/farmacologia , Animais , Dimetil Sulfóxido/farmacologia , Etilenoglicol/farmacologia , Feminino , Camundongos , Oócitos/efeitos dos fármacos , Vitrificação
9.
J Radiol Prot ; 36(4): 865-884, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27739409

RESUMO

The attribution of stochastic effects to exposure to ionizing radiation has been qualitatively discussed by introducing two distinct concepts of provability and probability. This study aims to develop a method of quantitatively assessing the provability of radiation-related cancers. To this end, the 'minimum provable dose' (MPD) was developed and applied to actual cancer mortality in Japan. The background lifetime risk of cancer mortality was calculated for the esophagus, stomach, colon, liver, lungs, skin, breasts, ovaries, bladder, and bone marrow as well as the age-specific risk coefficients reproducing those given in the 2007 Recommendations of the International Commission on Radiological Protection (ICRP). Comparing the relative ratio of MPDs, which was defined herein as the 'provability index' (PI), we quantitatively ranked radiation-related cancers for different tissues and organs predicated on provability for ages of 10, 30, 50, and 0-85+ years at exposure. We discuss the radiological protection of male emergency workers focusing on cancers highly prioritized according to the ranking (i.e. colon, bone marrow, and bladder). The present study proposed the system to quantitatively evaluate the level of radiological protection taking into account the variations of the background cancer risk on the provability of radiation-related cancers.


Assuntos
Neoplasias Induzidas por Radiação/etiologia , Doses de Radiação , Proteção Radiológica/métodos , Radiação Ionizante , Feminino , Humanos , Incidência , Japão/epidemiologia , Masculino , Neoplasias Induzidas por Radiação/epidemiologia , Exposição Ocupacional/efeitos adversos , Monitoramento de Radiação , Medição de Risco , Fatores de Risco
10.
Nature ; 518(7537): 85-8, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25653000

RESUMO

Plate tectonics successfully describes the surface of Earth as a mosaic of moving lithospheric plates. But it is not clear what happens at the base of the plates, the lithosphere-asthenosphere boundary (LAB). The LAB has been well imaged with converted teleseismic waves, whose 10-40-kilometre wavelength controls the structural resolution. Here we use explosion-generated seismic waves (of about 0.5-kilometre wavelength) to form a high-resolution image for the base of an oceanic plate that is subducting beneath North Island, New Zealand. Our 80-kilometre-wide image is based on P-wave reflections and shows an approximately 15° dipping, abrupt, seismic wave-speed transition (less than 1 kilometre thick) at a depth of about 100 kilometres. The boundary is parallel to the top of the plate and seismic attributes indicate a P-wave speed decrease of at least 8 ± 3 per cent across it. A parallel reflection event approximately 10 kilometres deeper shows that the decrease in P-wave speed is confined to a channel at the base of the plate, which we interpret as a sheared zone of ponded partial melts or volatiles. This is independent, high-resolution evidence for a low-viscosity channel at the LAB that decouples plates from mantle flow beneath, and allows plate tectonics to work.

11.
Cell Death Differ ; 22(2): 311-22, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25257171

RESUMO

The transcription factor adenovirus E2 promoter-binding factor (E2F)-1 normally enhances cell-cycle progression, but it also induces apoptosis under certain conditions, including DNA damage and serum deprivation. Although DNA damage facilitates the phosphorylation and stabilization of E2F1 to trigger apoptosis, how serum starvation renders cells vulnerable to E2F1-induced apoptosis remains unclear. Because poly(ADP-ribose) polymerase 1 (PARP1), a nuclear enzyme essential for genomic stability and chromatin remodeling, interacts directly with E2F1, we investigated the effects of PARP1 on E2F1-mediated functions in the presence and absence of serum. PARP1 attenuation, which increased E2F1 transactivation, induced G2/M cell-cycle arrest under normal growth conditions, but enhanced E2F1-induced apoptosis in serum-starved cells. Interestingly, basal PARP1 activity was sufficient to modify E2F1 by poly(ADP-ribosyl)ation, which stabilized the interaction between E2F1 and the BIN1 tumor suppressor in the nucleus. Accordingly, BIN1 acted as an RB1-independent E2F1 corepressor. Because E2F1 directly activates the BIN1 gene promoter, BIN1 curbed E2F1 activity through a negative-feedback mechanism. Conversely, when the BIN1-E2F1 interaction was abolished by PARP1 suppression, E2F1 continuously increased BIN1 levels. This is functionally germane, as PARP1-depletion-associated G2/M arrest was reversed by the transfection of BIN1 siRNA. Moreover, PARP-inhibitor-associated anti-transformation activity was compromised by the coexpression of dominant-negative BIN1. Because serum starvation massively reduced the E2F1 poly(ADP-ribosyl)ation, we conclude that the release of BIN1 from hypo-poly(ADP-ribosyl)ated E2F1 is a mechanism by which serum starvation promotes E2F1-induced apoptosis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Difosfato de Adenosina/metabolismo , Apoptose , Fator de Transcrição E2F1/metabolismo , Proteínas Nucleares/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Células 3T3 , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Divisão Celular , Linhagem Celular , Dano ao DNA , Fator de Transcrição E2F1/genética , Humanos , Camundongos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/genética , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/genética , Regiões Promotoras Genéticas , Proteínas Supressoras de Tumor/genética
12.
J Wound Care ; 24(1): 41-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25543822

RESUMO

OBJECTIVE: In the treatment of pressure ulcers and leg ulcers it is necessary to achieve an effective balance between adhesive and skin-protective properties. We speculated that addition of a tackifying agent (TA) to ceramide 2-containing hydrocolloid dressings would increase their adhesiveness under dry conditions and reduce their adhesiveness under wet conditions because dry tack converts to wet tack after water absorption. METHOD: We prepared ceramide 2-containing hydrocolloid dressings with varying amounts of TA. Basic characteristics of the test ceraminde dressings, such as initial tack force and peeling force, were evaluated using standard methods. Peeling force and stratum corneum (SC) removal on healthy human skin were also evaluated at 20 minutes, 7 hours, and 72 hours. In addition, the effect of 10 repeated applications on transepidermal water loss (TEWL) was investigated on the skin of hairless mice under dry and wet conditions. Statistical analyses were performed using one-way analysis of variance followed by Dunnett's multiple comparison test. A p-value of <0.05 was considered statistically significant. RESULTS: On a stainless steel substrate, initial tack force and 180° peeling force increased as TA content increased. Twenty minutes after application on human skin, peeling force and SC removal increased with increasing TA content. When TA contents were over 10%, significant differences in peeling force and SC removal were obtained compared with ceramide 2-containing hydrocolloid dressings without TA (p<0.05). However, a TA content-dependent increase in peeling force was not evident 7 hours and 72 hours after application. Under dry conditions, TEWL increased with repeated application and peeling. Conversely, no significant increases in TEWL were evident under wet conditions after 10 repeated applications and peelings. CONCLUSION: Our data demonstrate that the initial attachment of ceramide 2-containing hydrocolloid dressings to the skin increases with addition of TA. Skin damage can be avoided by conversion of the adhesive system to wet tack with water absorption. DECLARATION OF INTEREST: Masushi Kohta and Tetsuji IwasakI are employees of ALCARE Co., Ltd., Japan. This project was supported by an unrestricted grant from ALCARE.


Assuntos
Curativos Hidrocoloides , Ceramidas/uso terapêutico , Epiderme/efeitos dos fármacos , Epiderme/lesões , Fita Cirúrgica , Animais , Voluntários Saudáveis , Humanos , Camundongos Pelados , Perda Insensível de Água/efeitos dos fármacos
13.
J Environ Radioact ; 139: 416-426, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24909793

RESUMO

A numerical model capable of simulating the transfer of (137)Cs in rivers associated with transport of fine sediment is presented. The accident at Fukushima Dai-ichi Nuclear Power Plant (FDNPP) released radionuclides into the atmosphere, and after fallout several radionuclides in them, such as radiocesium ((134)Cs, (137)Cs) and radioiodine ((131)I) were adsorbed on surface soil particles around FDNPP and transported by surface water. To understand the transport and deposition of the radioactive contaminant along with surface soil particles and its flux to the ocean, we modeled the transport of the (137)Cs contaminant by computing the water flow and the associated washload and suspended load transport. We have developed a two-dimensional model to simulate the plane flow structure, sediment transport and associated (137)Cs contaminant transport in rivers by combining a shallow water flow model and an advection-diffusion equation for the transport of sediment. The proposed model has been applied to the lower reach of Abukuma River, which is the main river in the highly contaminated area around FDNPP. The numerical results indicate that most (137)Cs supplied from the upstream river reach with washload would directly reach to Pacific Ocean. In contrast, washload-oriented (137)Cs supplied from the upstream river basin has a limited role in the radioactive contamination in the river. The results also suggest that the proposed framework of computational model can be a potential tool for understanding the sediment-oriented (137)Cs behavior in rivers.


Assuntos
Radioisótopos de Césio/análise , Césio/análise , Sedimentos Geológicos/análise , Modelos Teóricos , Monitoramento de Radiação/métodos , Rios/química , Poluentes Radioativos da Água/análise , Simulação por Computador , Acidente Nuclear de Fukushima , Japão , Movimentos da Água
14.
Singapore Med J ; 55(6): 318-24, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25017407

RESUMO

INTRODUCTION: The ability to predict the prognosis of patients with pneumonia is critical, especially when making decisions regarding treatment regimens and sites of care. However, prognostic guidelines for healthcare-associated pneumonia (HCAP) have yet to be established. I-ROAD is the prognostic guideline of the Japanese Respiratory Society for hospital-acquired pneumonia (HAP). This study compared available prognostic guidelines to determine the usefulness of I-ROAD as a prognostic tool for patients with HCAP. METHODS: We conducted a retrospective review of all patients with pneumonia admitted to Kameda Medical Center, Japan, from January 2006 to September 2009. Patients were categorised into two groups, namely those with community acquired pneumonia (CAP) and those with HCAP. We compared the baseline characteristics, laboratory findings, identified pathogens, antibiotic regimens, clinical outcomes, pneumonic severity and prognostic accuracy of each guideline between the two patient groups. The severity of each disease was assessed on admission using the A-DROP, CURB-65, PSI and I-ROAD guidelines. RESULTS: Of the 302 patients evaluated, 228 (75.5%) were diagnosed with CAP and 74 (24.5%) with HCAP. Patients with HCAP were older and had a higher performance status than patients with CAP. The mortality rate in the CAP group tended to rise with increasing severity scores of prognostic guidelines. Although the severity scores of all prognostic guidelines could predict 30-day mortality in patients with CAP, I-ROAD exhibited a higher discriminatory power for patients with HCAP based on analysis of receiver-operating characteristic curves. CONCLUSION: I-ROAD could be more accurate than other prognostic guidelines for evaluating the severity of HCAP.


Assuntos
Infecções Comunitárias Adquiridas/diagnóstico , Infecção Hospitalar/diagnóstico , Infectologia/normas , Pneumonia/diagnóstico , Idoso , Feminino , Humanos , Japão , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Sociedades Médicas
15.
Transplant Proc ; 46(3): 797-803, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24767352

RESUMO

BACKGROUND: Along with an increased number of cases of liver transplantation (LT), perioperative mortality has decreased and short-term survival has improved. However, long-term complications have not been fully elucidated today. PURPOSE: Chronic complications were analyzed individually to find risk factors and to improve long-term outcomes after LT. SUBJECTS: There were 63 cases of LT from our outpatient clinic that were included in this study. Among them, 58 were performed using living donor LT and 5 were performed using deceased donor LT. Original diseases mainly consisted of hepatitis C virus (HCV; 45.9%) and hepatitis B virus (23.0%). FINDINGS: The median follow-up was 5.4 ± 3.3 years (range, 0.1∼17 years). Overall survival at 2, 3, 5, and 10 years was 89.3%, 83.4%, 81.3%, and 81.3%, respectively. Long-term complications mainly consisted of renal dysfunction (62.7%), dyslipidemia (29.4%), diabetes mellitus (21.6%), and arterial hypertension (21.6%). In univariate analysis, HCV (P = .03) and elapsed years after LT (P = .02) were identified as predictive factors for arterial hypertension and recipient age >50 (P = .03), and elapsed years after LT for renal dysfunction (P = .03), respectively. In multivariate Cox regression analysis, HCV (odds ratio [OR] 5.25, 95% confidence interval [CI] 1.05-34.06, P = .04) was identified as a predictive factor for arterial hypertension, and recipient age older than 50 years for renal dysfunction (OR 5.67, 95% CI 1.34-28.88, P = .02). The number of elapsed years after transplantation was also identified as a predictive factor for arterial hypertension/dyslipidemia/renal dysfunction (OR 13.88/14.15/4.10, 95% CI 1.91-298.26/2.18-290.78/1.09-18.03, P = .01/.003/.04). Fifty percent of the recipients developed renal dysfunction within 8 years after LT, and fluctuation of estimated glomerular filtration rate (eGFR) within 3 months after LT was successfully associated with an annual decrease of eGFR (r(2) value = 0.574, P < .0001). CONCLUSION: Renal dysfunction is the most frequent chronic complication after LT. As chronic individual eGFR can be now accurately predicted with deterioration speed, recipient strata for renal protection strategies should be precisely targeted.


Assuntos
Transplante de Fígado/efeitos adversos , Adulto , Idoso , Causas de Morte , Taxa de Filtração Glomerular , Humanos , Pessoa de Meia-Idade , Doadores de Tecidos
16.
J Neuroendocrinol ; 26(3): 164-75, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24460919

RESUMO

Thyroid hormones play crucial roles in the development and functional maintenance of the central nervous system. Despite extensive studies of the neural function of thyroid hormones, little is known about the effects of hypothyroidism on behavioural traits and the mechanisms underlying such effects. In the present study, we report an investigation of congenitally hypothyroid mutant rdw rats, revealing a novel function of thyroid hormones in the central nervous system. The rdw rats were subjected to behavioural analyses such as the rotarod test, open field test and circadian activity measurement. To determine the cause of behavioural disorders, cerebellar morphogenesis was examined by immunohistochemical analysis, and the axonal transport of dopamine in the nigrostriatal pathway was analysed by high-performance liquid chromatography and western blotting. The effects of thyroxine administration to the rdw rats were examined by behavioural analysis. The rdw rats showed severe impairment of motor coordination and balance. This could be explained by the fact that the rats showed severe retardation of cerebellar morphogenesis, which correlates with the small somata and poor dendritic arborisation of Purkinje cells and retarded migration of granule cells particularly during the first two postnatal weeks. Moreover, the rdw rats showed hypoactivity, characterised by decreased circadian locomotor activity. After weaning, thyroxine administration improved the dwarfism in rdw rats but had no effect on cerebellar function. In addition, the rdw rats showed anxiety and depression intrinsically to novel surroundings. Interestingly, the rdw rats showed high levels of dopamine in the substantia nigra and low levels in the striatum, an important centre for the coordination of behaviour. Furthermore, low levels of tubulin in the striatum were detected, indicating the aberrant axonal transport of dopamine in the nigrostriatal pathway as a result of the reduced delivery of microtubules. These findings indicate an important function of thyroid hormones in cerebellar formation and in the regulation of axonal transport of dopamine. Moreover, rdw rats will be useful for studies of brain function and behavioural disorders in congenital hypothyroidism.


Assuntos
Hipotireoidismo Congênito/patologia , Corpo Estriado/crescimento & desenvolvimento , Dopamina/metabolismo , Substância Negra/crescimento & desenvolvimento , Animais , Western Blotting , Cromatografia Líquida de Alta Pressão , Hipotireoidismo Congênito/genética , Hipotireoidismo Congênito/metabolismo , Corpo Estriado/metabolismo , Feminino , Masculino , Desempenho Psicomotor , Ratos , Teste de Desempenho do Rota-Rod , Substância Negra/metabolismo , Hormônios Tireóideos/sangue , Tiroxina/administração & dosagem
17.
J Fish Dis ; 37(7): 619-27, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23952965

RESUMO

Serum biochemical analysis was undertaken to study the pathophysiological details of emaciation disease of the tiger puffer fish Takifugu rubripes (Temminck and Schlegel). Serum parameters were measured by biochemical analysis using automated dry chemistry and gas chromatography/mass spectrometry (GC/MS). Serum concentrations of albumin, amylase, calcium, creatinine, glucose and total protein were significantly lower in the emaciated fish when compared with those of normal fish. Regression analyses found close correlation between concentrations of total protein, albumin, amylase, glucose and progress of the disease. In contrast, serum alanine aminotransferase increased significantly in emaciated fish indicating liver function disorder. Further, GC/MS metabolic profiling of the puffer serum showed that the profile of the emaciated fish was distinct to that of non-infected control. The serum content of amino acids including glycine, 5-oxo-proline and proline, and ascorbic acid, fumaric acid and glycerol increased significantly in serum in moderately emaciated fish. The serum glucose, linolenic acid and tyrosine level decreased significantly in the late phase of the disease. Our results clearly show that prolonged intestinal damage caused by myxosporean infection impairs absorption of nutrients, resulting in extreme emaciation.


Assuntos
Emaciação/veterinária , Doenças dos Peixes/fisiopatologia , Metaboloma , Myxozoa/isolamento & purificação , Myxozoa/microbiologia , Doenças Parasitárias em Animais/fisiopatologia , Takifugu , Animais , Análise Química do Sangue/veterinária , Emaciação/enzimologia , Emaciação/parasitologia , Emaciação/fisiopatologia , Enzimas/sangue , Doenças dos Peixes/enzimologia , Doenças dos Peixes/parasitologia , Cromatografia Gasosa-Espectrometria de Massas/veterinária , Intestinos/enzimologia , Intestinos/parasitologia , Intestinos/fisiopatologia , Doenças Parasitárias em Animais/enzimologia , Doenças Parasitárias em Animais/parasitologia
18.
Cerebellum ; 12(4): 572-86, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23475384

RESUMO

In the present study, we examined the effect of perinatal Escherichia coli lipopolysaccharide (LPS) exposure on the developing rat cerebellum and tested the hypothesis that maternal infections impact brain structure and function by mechanisms involving increase in oxidative stress and changes in brain type 2 iodothyronine deiodinase (D2)- and thyroid hormone (TH)-responsive genes. Spontaneously hypertensive rat (SHR) and Sprague-Dawley (SD) rat dams were challenged with LPS (200 µg/kg body weight) exposure during pregnancy (G10-G15) and lactation (P5-P10), the time periods corresponding, respectively, to the first/second and the third trimesters of human pregnancy. LPS exposure resulted in a significantly decreased motor learning in SD male (29.8 %) and in female (55.0 %) pups (p < 0.05); changes in rollover and startle response showed only a trend. The LPS challenge also resulted in a trend (p = 0.09) toward increased cerebellar levels of the oxidative stress marker 3-nitrotyrosine (3-NT) in SD male (16.2 %) and female (21.2 %) neonates, while 3-NT levels were significantly decreased (p < 0.05) in SHR female pups. D2 activity, responsible for local intra-brain conversion of thyroxine (T4) to the active hormone, 3',3,5-triiodothyronine (T3), was significantly (p < 0.05) decreased in LPS-challenged SHR male (40.3 %) and SD female (47.4 %) pups. Several genes were affected by LPS. Notably, D2 (DIO2) and brain-derived neurotrophic factor (BDNF) were significantly elevated in SHR females, while transthyretin (TTR) expression was decreased in both SD males and females (P < 0.05). In vitro chronic exposure of cerebellar cultures to LPS resulted in decreased arborization of Purkinje cells while D2 was only increased transiently. Our data demonstrate that perinatal LPS exposure impacts the developing cerebellum in strain- and sex-dependent manner via complex mechanisms that involve changes in oxidative stress, enzymes involved in maintaining local TH homeostasis, and downstream gene expression.


Assuntos
Cerebelo/crescimento & desenvolvimento , Cerebelo/metabolismo , Modelos Animais de Doenças , Lipopolissacarídeos/toxicidade , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Animais , Animais Recém-Nascidos , Infecções Bacterianas/induzido quimicamente , Infecções Bacterianas/metabolismo , Células Cultivadas , Cerebelo/efeitos dos fármacos , Feminino , Humanos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Gravidez , Ratos , Ratos Endogâmicos SHR , Ratos Sprague-Dawley , Fatores Sexuais , Especificidade da Espécie
19.
J Small Anim Pract ; 54(4): 201-4, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23496103

RESUMO

A six-year-old, neutered, female golden retriever was presented with generalised, dark purple to black cutaneous nodules and gastrointestinal haemorrhage. Histopathologically, all cutaneous nodules were diagnosed as benign cavernous haemangiomas. Endoscopic analysis revealed similar nodules in the oesophagus, stomach and duodenum. At laparotomy, similar nodules were seen on the visceral peritoneal lining of abdominal organs. Metastatic haemangiosarcoma was ruled out based on histological features and lack of primary tumour in spleen, liver or heart ultrasonographically. Blood loss associated with gastrointestinal haemorrhage was managed with blood transfusion. To the authors' knowledge, this is the first canine case of multi-system progressive angiomatosis resembling blue rubber bleb nevus syndrome in humans.


Assuntos
Angiomatose/veterinária , Doenças do Cão/diagnóstico , Hemangioma/veterinária , Angiomatose/diagnóstico , Animais , Diagnóstico Diferencial , Cães , Feminino , Hemangioma/diagnóstico , Humanos , Nevo Azul/diagnóstico , Nevo Azul/veterinária , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/veterinária , Síndrome
20.
Arch Oral Biol ; 57(3): 307-13, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21975117

RESUMO

Head rotation is coordinated with mandibular movement during mouth opening, and the range of head rotation and mouth opening change with food size. However, past research did not include upper body movement, and no reports have related head and mandibular movement during realistic eating. The purpose of this study was to analyse head and mandibular movements with intake of different-sized food pieces during realistic eating. The test food consisted of apple cut into two different cube sizes (10mm and 20mm). Head and mandibular movements of 20 healthy young adults eating the apple pieces were simultaneously recorded in three dimensions by a wireless opto-electronic system. Reflective markers were attached to the upper lip and chin to measure the mouth opening range. Five markers were attached to eyeglasses frames to measure linear motion and rotation of the head. One marker was attached to the jugular notch of the sternum to measure linear motion of the upper body. Linear motion, and the inclination angle of the head and upper body, and mouth opening range were compared during intake of different-sized apple pieces. Mouth opening, head-neck rotation angle and the amount of upper body forward translation and inclination increased with larger apple pieces. However, isolated relative head motion was stabilized. We conclude that upper body forward motion and head-neck rotation assist mouth opening whilst stabilizing head orientation, and that the range of head-neck rotation angle, upper body translation and range of mouth opening change with food size during realistic eating.


Assuntos
Ingestão de Alimentos/fisiologia , Movimentos da Cabeça/fisiologia , Mandíbula/fisiologia , Movimento/fisiologia , Tórax/fisiologia , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Boca/fisiologia , Pescoço/fisiologia , Amplitude de Movimento Articular , Fatores Sexuais
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