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1.
Nature ; 560(7720): 613-616, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30158605

RESUMO

Galaxies in the early Universe that are bright at submillimetre wavelengths (submillimetre-bright galaxies) are forming stars at a rate roughly 1,000 times higher than the Milky Way. A large fraction of the new stars form in the central kiloparsec of the galaxy1-3, a region that is comparable in size to the massive, quiescent galaxies found at the peak of cosmic star-formation history4 and the cores of present-day giant elliptical galaxies. The physical and kinematic properties inside these compact starburst cores are poorly understood because probing them at relevant spatial scales requires extremely high angular resolution. Here we report observations with a linear resolution of 550 parsecs of gas and dust in an unlensed, submillimetre-bright galaxy at a redshift of z = 4.3, when the Universe was less than two billion years old. We resolve the spatial and kinematic structure of the molecular gas inside the heavily dust-obscured core and show that the underlying gas disk is clumpy and rotationally supported (that is, its rotation velocity is larger than the velocity dispersion). Our analysis of the molecular gas mass per unit area suggests that the starburst disk is gravitationally unstable, which implies that the self-gravity of the gas is stronger than the differential rotation of the disk and the internal pressure due to stellar-radiation feedback. As a result of the gravitational instability in the disk, the molecular gas would be consumed by star formation on a timescale of 100 million years, which is comparable to gas depletion times in merging starburst galaxies5.

2.
Clin Radiol ; 79(3): 213-220, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38218706

RESUMO

AIM: To evaluate the efficacy of using the central venous (CV) port compared with peripheral intravenous access for contrast-material injection for contrast enhancement during the portal venous phase. MATERIALS AND METHODS: Patients were divided into three groups: CV delay, CV routine, and peripheral access (PA) groups. Patients in the CV delay group underwent injection in the arm-down position with an additional delay, while those in the CV routine and PA groups underwent injections with the routine injection protocol for portal venous phase imaging. Contrast enhancement was evaluated by measuring the mean radiodensity (Hounsfield units) values for the aortic arch, abdominal aorta, inferior vena cava, portal vein, and spleen. The peak injection pressure was recorded and compared among the three groups. RESULTS: No complications related to power injection were observed during 119 contrast-material injections performed using the CV port device. The CV delay group showed significantly lower radiodensity values than the PA group (165.7 ± 20.1 versus 181 ± 19 HU [p<0.01] for the portal vein); however, no significant differences in mean radiodensity values were observed between the CV routine and PA groups (p>0.05). The median peak injection pressure was 73.5, 67, and 47 psi in the CV delay, CV routine, and PA groups, respectively (p<0.01). CONCLUSION: The CV port can be used for safe contrast-material injection while maintaining contrast enhancement on portal venous phase comparable to that achieved with peripheral intravenous access.


Assuntos
Cateterismo Venoso Central , Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Meios de Contraste , Injeções Intravenosas , Veia Cava Inferior
3.
Clin Radiol ; 77(12): 935-942, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36302714

RESUMO

AIM: To identify the magnetic resonance imaging (MRI) features of metastases to the extraocular muscles (EOM metastases). MATERIAL AND METHODS: The MRI features of 19 patients with EOM metastases were compared with those of 24 patients with EOM diseases of non-thyroid origin. MRI was used to assess the number of tumours, morphology, signal intensity on T2-weighted images, enhancement patterns, and apparent diffusion coefficient (ADC) values. RESULTS: Single muscular involvement was observed in 10 patients, and multiple muscular involvement was observed in nine patients. The morphology was focally discrete in nine patients, and diffuse infiltrative in 10 patients; all the nine patients with focal discrete morphology presented with single muscular lesions. On T2-weighted images, the signal intensities were intermediate or low in 15 patients and a mixture of high and intermediate in four patients. In 14 patients for whom contrast-enhanced images were available, ring enhancement (n=5), heterogeneous diffuse enhancement (n=5), and homogeneous enhancement (n=4) were seen. The mean ADC value was 0.98 × 10-3 mm2/s. Compared to other EOM diseases of non-thyroid origin, single muscular presentation, focal discrete morphology, the presence of hyperintensity on T2-weighted images, and ring or heterogeneous enhancement were significantly more frequent in EOM metastases. CONCLUSION: The MRI features of EOM metastases showed two main patterns: a single discrete mass and multiple infiltrative masses. In addition to the presentation as a single discrete mass, the presence of hyperintensity on T2-weighted images and ring or heterogeneous enhancement can aid in the differentiation of EOM metastases from other EOM diseases.


Assuntos
Músculos Oculomotores , Doenças Orbitárias , Humanos , Músculos Oculomotores/diagnóstico por imagem , Músculos Oculomotores/patologia , Meios de Contraste , Imageamento por Ressonância Magnética/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Estudos Retrospectivos
4.
Nature ; 510(7504): 247-9, 2014 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-24919918

RESUMO

Long-duration γ-ray bursts are associated with the explosions of massive stars and are accordingly expected to reside in star-forming regions with molecular gas (the fuel for star formation). Previous searches for carbon monoxide (CO), a tracer of molecular gas, in burst host galaxies did not detect any emission. Molecules have been detected as absorption in the spectra of γ-ray burst afterglows, and the molecular gas is similar to the translucent or diffuse molecular clouds of the Milky Way. Absorption lines probe the interstellar medium only along the line of sight, so it is not clear whether the molecular gas represents the general properties of the regions where the bursts occur. Here we report spatially resolved observations of CO line emission and millimetre-wavelength continuum emission in two galaxies hosting γ-ray bursts. The bursts happened in regions rich in dust, but not particularly rich in molecular gas. The ratio of molecular gas to dust (<9-14) is significantly lower than in star-forming regions of the Milky Way and nearby star-forming galaxies, suggesting that much of the dense gas where stars form has been dissipated by other massive stars.

6.
Spinal Cord ; 55(4): 419-426, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27801888

RESUMO

STUDY DESIGN: Retrospective study. OBJECTIVES: Few studies have reported a relationship between central motor conduction time (CMCT), which evaluates corticospinal function, and degree of spinal cord compression in patients with myelopathy. Thus, there is no consensus on predicting the degree of prolonged CMCT on the basis of the degree of spinal cord compression. If a correlation exists between CMCT and spinal cord compression, then spinal cord compression may be a useful noninvasive clinical indicator of corticospinal function. Therefore, this study evaluated the relationship between CMCT and cervical spinal cord compression measured by magnetic resonance imaging (MRI) in patients with cervical spondylotic myelopathy (CSM). SETTING: Hiroshima University Hospital in Japan. METHODS: We studied 33 patients undergoing laminoplasty. Patients exhibited significant cervical spinal cord compression on both MRI and intraoperative electrophysiological examination. We assessed transcranial magnetic stimulation measurement of CMCT; spinal cord compression parameters such as area, lateral diameter, anteroposterior diameter and flattening of the spinal cord at the lesion site and C2/3 levels on MRI; and pre- versus postoperative Japanese Orthopaedic Association (JOA) scores. RESULTS: Correlations between CMCT and flattening as well as anteroposterior diameter of the spinal cord at the lesion level were observed. Strong correlations between CMCT and the ratio of the flattening and anteroposterior diameter parameters at the lesion level to that at the C2/3 level were also observed. CONCLUSIONS: Measurement of spinal cord compression may be useful for the evaluation of corticospinal function as a proxy for CMCT in patients with CSM.


Assuntos
Condução Nervosa/fisiologia , Compressão da Medula Espinal/diagnóstico por imagem , Compressão da Medula Espinal/fisiopatologia , Espondilose/diagnóstico por imagem , Espondilose/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Potencial Evocado Motor/fisiologia , Feminino , Hospitais Universitários , Humanos , Monitorização Neurofisiológica Intraoperatória , Laminoplastia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Estudos Retrospectivos , Medula Espinal/diagnóstico por imagem , Medula Espinal/fisiopatologia , Compressão da Medula Espinal/complicações , Compressão da Medula Espinal/cirurgia , Espondilose/complicações , Espondilose/cirurgia , Fatores de Tempo , Estimulação Magnética Transcraniana , Resultado do Tratamento
7.
Br J Surg ; 103(1): 60-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26572241

RESUMO

BACKGROUND: The aim of this study was to evaluate whether MRI at 3 T with superparamagnetic iron oxide (SPIO) enhancement is an accurate and useful method for detecting metastases in sentinel nodes identified by CT-lymphography (CT-LG) in patients with breast cancer. The results were compared with those obtained using CT-LG alone and diagnosing metastasis according to size criteria. METHODS: Patients with clinically node-negative breast cancer were included. Sentinel nodes identified by CT-LG were evaluated prospectively using SPIO-enhanced MRI at 3 T. Sentinel node size was measured on CT-LG, and a node larger than 5 mm in short-axis diameter was considered metastatic. Sentinel nodes localized by CT-LG were removed, and imaging results and histopathological findings were compared. RESULTS: Sentinel nodes were identified successfully by CT-LG in 69 (99 per cent) of 70 patients. All 19 patients with a finding of metastasis in sentinel nodes at pathology were also shown to have metastases on MRI. Forty-eight of 50 patients with non-metastatic sentinel nodes diagnosed at pathology were classified as having non-metastatic nodes on MRI. On a patient-by-patient basis, the sensitivity, specificity and accuracy of MRI for the diagnosis of sentinel node metastases were 100, 96 and 97 per cent; respective values for CT-LG were 79, 56 and 62 per cent. The specificity and accuracy of MRI were superior to those of CT-LG (P < 0·001 and P = 0·002 respectively). CONCLUSION: SPIO-enhanced MRI at 3 T is useful for accurate diagnosis of metastatic sentinel nodes, indicating that sentinel node biopsy may be avoided in patients with breast cancer who have non-metastatic sentinel nodes on imaging.


Assuntos
Neoplasias da Mama/patologia , Meios de Contraste , Compostos Férricos , Linfonodos/patologia , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X , Adulto , Idoso , Axila , Neoplasias da Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Lobular/diagnóstico por imagem , Carcinoma Lobular/patologia , Feminino , Humanos , Linfonodos/diagnóstico por imagem , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Sensibilidade e Especificidade
8.
Clin Exp Obstet Gynecol ; 43(6): 902-904, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29944250

RESUMO

PURPOSE: The authors report on a rare case of maternal virilization during pregnancy caused by autosomal recessive P450 oxidore- ductase (POR) deficiency. MATERIALS AND METHODS: A 24-year-old primigravida developed a deepening voice and hirsutism in the second trimester. Prenatal ultrasonography failed to detect any fetal abnormality and fetal growth was normal. POR deficiency was suspected, but the mother declined fetal genetic testing. A female neonate was delivered by cesarean section at 41 weeks' gestation. RESULTS: The neonate had skeletal abnormalities. Mutational analysis of the POR gene demonstrated homozygosity for c.1370 G>A and p.R457H in the patient and heterozygosity in her parents. POR deficiency was confirmed in the neonate. CONCLUSION: POR deficiency should be suspected in cases of maternal virilization. Maternal urinary estriol, fetal magnetic resonance imaging, and parental genetic testing should be performed. Parental consent for fetal genetic testing should be sought to ensure prompt diagnosis and early treatment.


Assuntos
Fenótipo de Síndrome de Antley-Bixler/fisiopatologia , Complicações na Gravidez/fisiopatologia , Virilismo/fisiopatologia , Fenótipo de Síndrome de Antley-Bixler/complicações , Fenótipo de Síndrome de Antley-Bixler/genética , Clitóris/anormalidades , Feminino , Testes Genéticos , Humanos , Recém-Nascido , Mutação , Linhagem , Gravidez , Complicações na Gravidez/genética , Segundo Trimestre da Gravidez , Ultrassonografia Pré-Natal , Virilismo/etiologia , Virilismo/genética , Adulto Jovem
11.
Br J Surg ; 101(4): 398-407, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24536011

RESUMO

BACKGROUND: The pathophysiology of intra-abdominal adhesions has not been studied extensively. The aim of this study was to elucidate the molecular mechanisms underlying adhesion formation in a murine model and in patients undergoing hepatectomy. METHODS: Partial hepatectomy was performed using bipolar forceps in mice. Wild-type mice, antibodies to CD4 and interferon (IFN) γ, IFN-γ, natural killer T (NKT) cells and plasminogen activator inhibitor (PAI) 1 knockout (KO) mice were used. Recombinant hepatocyte growth factor (HGF) was tested for its ability to prevent adhesions. Liver specimens were obtained during surgery from patients undergoing hepatectomy. Adhesion formation was evaluated using a scoring system that ranged from 0 (no adhesions) to 5 (severe adhesions). Levels of IFN-γ and PAI-1 mRNA, and protein concentration of PAI-I were measured, and fluorescence immunostaining was performed. RESULTS: Adhesion formation depended on IFN-γ produced by NKT cells, and NKT KO mice developed few adhesions (mean(s.d.) 1·7(0·3) versus 4·6(0·4) in wild-type mice; P = 0·037). In wild-type mice, the level of PAI-1 mRNA increased after hepatectomy, followed by a decrease in the tissue plasminogen activator (tPA) mRNA level. Adhesion formation was inhibited completely in PAI-1 KO mice (0(0) versus 4·1(0·8) in wild-type mice; P = 0·002). HGF inhibited formation of abdominal adhesions after hepatectomy by reducing IFN-γ and PAI-1 levels, and increasing tPA levels compared with those in mice treated with phosphate-buffered saline (P < 0·001, P = 0·002 and P = 0·035 respectively). In human liver specimens, NKT cells accumulated in the liver after hepatectomy, and PAI-1 expression was increased 5·25-fold (P = 0·030). CONCLUSION: IFN-γ is a key molecule for abdominal adhesion formation after hepatectomy, acting via the reciprocal balance of PAI-1 and tPA. This molecular mechanism may also regulate adhesion formation in patients following hepatectomy. HGF inhibited formation of adhesions by regulating IFN-γ and PAI-1, suggesting that it may be an important target for prevention of adhesions after hepatectomy. SURGICAL RELEVANCE: Postoperative intra-abdominal adhesions can be asymptomatic or cause significant morbidity and mortality. Adhesion formation after hepatectomy has not been studied extensively. In the present study, the molecular mechanisms underlying intra-abdominal adhesions after hepatectomy were investigated in a murine model and in patients. Interferon (IFN) γ produced by natural killer T cells is a key molecule for adhesion formation after hepatectomy in mice, acting via the reciprocal balance between plasminogen activator inhibitor (PAI) 1 and tissue plasminogen activator, the pivotal factors in fibrinolytic activity. This mechanism was also involved in the regulation of adhesions in human tissue samples. Hepatocyte growth factor (HGF) strongly inhibited adhesion formation by regulating IFN-γ and PAI-1. These results indicate that IFN-γ and PAI-1 are possible therapeutic targets, and HGF could prevent postoperative adhesion formation after hepatectomy.


Assuntos
Interferon gama/fisiologia , Inibidor 1 de Ativador de Plasminogênio/fisiologia , Aderências Teciduais/fisiopatologia , Animais , Antígenos CD4/farmacologia , Ensaio de Imunoadsorção Enzimática , Feminino , Hepatectomia/efeitos adversos , Fator de Crescimento de Hepatócito/farmacologia , Humanos , Células Matadoras Naturais , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Recombinantes
12.
Phys Rev Lett ; 112(11): 112502, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24702355

RESUMO

Gamow-Teller (GT) transitions in atomic nuclei are sensitive to both nuclear shell structure and effective residual interactions. The nuclear GT excitations were studied for the mass number A = 42, 46, 50, and 54 "f-shell" nuclei in ((3)He, t) charge-exchange reactions. In the (42)Ca → (42)Sc reaction, most of the GT strength is concentrated in the lowest excited state at 0.6 MeV, suggesting the existence of a low-energy GT phonon excitation. As A increases, a high-energy GT phonon excitation develops in the 6-11 MeV region. In the (54)Fe → (54)Co reaction, the high-energy GT phonon excitation mainly carries the GT strength. The existence of these two GT phonon excitations are attributed to the 2 fermionic degrees of freedom in nuclei.

13.
Clin Radiol ; 69(1): 41-4, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24090910

RESUMO

AIM: To report the magnetic resonance imaging (MRI) and corresponding histopathological features of squamous cell carcinoma (SCC) originating in the parotid gland. MATERIALS AND METHODS: The MRI images of seven patients with histopathologically proven SCC originating in the parotid gland were reviewed retrospectively, with an emphasis on tumour size, shape, contour definition, extraparotid infiltration, signal characteristics, and the presence of central necrosis. These were correlated with the microscopic findings of the surgical specimens. RESULTS: The tumours ranged in size from 3.9-7 cm (mean 4.7 cm). All tumours had an ill-defined margin with extraparotid infiltration, which seemed to reflect the invasive growth of the tumour cells on histopathological examination. The solid portions of the tumours showed predominantly low to intermediate signal intensities on T2-weighted images, which seemed to reflect the high cellularity, intercellular bridges, and/or keratin pearl formation observed at histopathological examination. Five of the seven tumours had central necrosis. CONCLUSION: A relatively large tumour with central necrosis is a useful imaging feature of SCCs originating in the parotid gland, in addition to the well-recognized indicators of parotid malignancy, such as an ill-defined margin, extraparotid infiltration, and low to intermediate signal intensity on T2-weighted images.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Neoplasias Parotídeas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Neoplasias Parotídeas/patologia , Estudos Retrospectivos
14.
Spinal Cord ; 52 Suppl 3: S19-21, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25376311

RESUMO

STUDY DESIGN: Case report. OBJECTIVE: To report intraoperative spinal cord injury by resection of spinous processes in a 73-year-old man with ossification of the posterior longitudinal ligament (OPLL) in the thoracic spine. METHODS: A 73-year-old man presented with cervicothoracic OPLL with bilateral numbness and clumsiness of his hand, weakness of his lower extremities and severe gait disturbance. His Japanese Orthopaedic Association (JOA) score was 7.5 out of 17. Cervical laminoplasty (C2-6), cervicothoracic laminectomy (C7-T10) and posterior fusion (C7-T10) were performed in the prone position with electrophysiologic monitoring of the spinal cord-evoked potentials (SCEPs). RESULTS: The spinal processes with supra- and interspinous ligaments between C7 and T10 were resected. After resection, the amplitude of SCEP waveforms decreased rapidly to <10% of control levels. Laminectomy was performed, and, after 80 min of SCEP deterioration, an instrumented fusion with correction for kyphosis was completed. The SCEP amplitude recovered gradually. Immediately after surgery, the patient suffered severe motor loss in both lower limbs. His neurological recovery progressed gradually from 2 days after surgery, and he was able to walk at 3 months after surgery. At 6 years after surgery, the JOA score was 11. CONCLUSION: Our results suggest that intraoperative spinal cord injury can occur before posterior decompression by resection of spinal processes with supra- and interspinous ligaments. The timing of the instrumented stabilization using a temporary rod is important and should be considered immediately after posterior exposure of the spine.


Assuntos
Ossificação do Ligamento Longitudinal Posterior/cirurgia , Complicações Pós-Operatórias/etiologia , Traumatismos da Medula Espinal/etiologia , Idoso , Descompressão Cirúrgica/métodos , Humanos , Laminectomia/métodos , Masculino , Ossificação do Ligamento Longitudinal Posterior/diagnóstico , Compressão da Medula Espinal/cirurgia , Traumatismos da Medula Espinal/diagnóstico
15.
Oper Dent ; 49(3): 311-324, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38632849

RESUMO

OBJECTIVES: To investigate the influence of filler type/loading on the micro-tensile fracture strength (µTFS) of adhesive resins, as measured 'immediately' upon preparation and after 1-week water storage ('water-stored'). METHODS: The morphology and particle-size distribution of three filler particles, referred to as 'Glass-S' (Esschem Europe), 'BioUnion' (GC), and 'CPC_Mont', were correlatively characterized by SEM, TEM, and particle-size analysis. These filler particles were incorporated into an unfilled adhesive resin ('BZF-29unfilled', GC) in different concentrations to measure the 'immediate' µTFS. After 1-week water storage, the 'water-stored' µTFS of the experimental particle-filled adhesive resins with the most optimum filler loading, specific for each filler type, was measured. In addition, the immediate and water-stored µTFS of the adhesive resins of three experimental two-step universal adhesives based on the same resin matrix but varying for filler type/loading, coded as 'BZF-21' (containing silica and bioglass), 'BZF-29' (containing solely silica), and 'BZF-29_hv' (highly viscous with a higher silica loading than BZF-29), and of the adhesive resins of the gold-standard adhesives OptiBond FL ('Opti-FL', Kerr) and Clearfil SE Bond 2 ('C-SE2', Kuraray Noritake) was measured along with that of BZF-29unfilled (GC) serving as control/reference. Statistics involved one-way and two-way ANOVA followed by post-hoc multiple comparisons (α<0.05). RESULTS: Glass-S, BioUnion, and CPC_Mont represent irregular fillers with an average particle size of 8.5-9.9 µm. Adding filler to BZF-29unfilled decreased µTFS regardless of filler type/loading. One-week water storage reduced µTFS of all adhesive resins except BZF-21, with the largest reduction in µTFS recorded for BZF-29unfilled. Among the three filler types, the µTFS of the 30 wt% Glass-S and 20 wt% BioUnion filled adhesive resin was not significantly different from the µTFS of BZF-29unfilled upon water storage. CONCLUSIONS: Adding filler particles into adhesive resin did not enhance its micro-tensile fracture strength but appeared to render it less sensitive to water storage as compared to the unfilled adhesive resin investigated.


Assuntos
Teste de Materiais , Resistência à Tração , Cimentos de Resina/química , Resinas Compostas/química , Propriedades de Superfície , Tamanho da Partícula , Análise do Estresse Dentário , Cimentos Dentários/química , Humanos , Microscopia Eletrônica de Varredura
16.
Nature ; 443(7112): 649, 2006 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-17035994

RESUMO

In the absence of a red-sensitive visual pigment, some deep-sea fish use a chlorophyll derivative in their green-sensitive rod cells in order to see deep-red light. Here we show that living rods extracted from a salamander can also accumulate an exogenous chlorophyll derivative, chlorin e6, that renders them as sensitive to red light as they are to green. This vision enhancement by an unbleachable chlorophyll derivative might therefore be a general phenomenon in vertebrate photoreception.


Assuntos
Percepção de Cores/fisiologia , Cor , Porfirinas/metabolismo , Células Fotorreceptoras Retinianas Bastonetes/fisiologia , Urodelos/fisiologia , Animais , Bovinos , Clorofila/metabolismo , Clorofilídeos , Percepção de Cores/efeitos dos fármacos , Porfirinas/química , Porfirinas/farmacologia , Células Fotorreceptoras Retinianas Bastonetes/química , Células Fotorreceptoras Retinianas Bastonetes/citologia , Células Fotorreceptoras Retinianas Bastonetes/efeitos dos fármacos , Rodopsina/metabolismo
17.
Scand J Immunol ; 74(6): 574-84, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21883352

RESUMO

Shiga toxin 1 produced by enterohaemorrhagic Escherichia coli is an AB(5) toxin that is involved in the life-threatening haemolytic-uraemic syndrome. The B subunits (Stx1B) are cell-binding subunits. We previously established mouse hybridoma cell line producing IgA and IgG monoclonal antibodies (mAbs) against Stx1B. Here, we cloned cDNAs encoding each of the heavy, light and joining (J) chains from the hybridoma cell lines by means of the 5' rapid amplification of cDNA ends (RACE) PCR method. Upon assignment of the variable regions of the heavy and light chains to known germline sequences, we found substantial somatic hypermutation in the complementarity-determining regions in both the IgA and IgG mAbs. We also established a hybrid-IgG/IgA heavy chain having variable regions of the IgG mAb by means of recombinant PCR methods. Upon transient expression of the hybrid-IgG/IgA heavy, IgG-associated light and J chains in COS-1 cells, the translated dimeric hybrid-IgG/IgA bound to immobilized Stx1B, as revealed on ELISA. The production of dimeric hybrid-IgG/IgA was revealed on immunoblot analysis. The dimeric hybrid-IgG/IgA inhibited the binding of digoxigenin-conjugated Stx1B to natural ligands (CD77) displayed on Burkitt's lymphoma cell line Ramos. These results indicate that the replacement of variable regions resulted in the production of more useful recombinant dimeric IgA against Stx1B.


Assuntos
Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Toxina Shiga/imunologia , Sequência de Aminoácidos , Animais , Especificidade de Anticorpos , Sequência de Bases , Imunoglobulina A/química , Imunoglobulina A/genética , Imunoglobulina G/química , Imunoglobulina G/genética , Camundongos , Dados de Sequência Molecular , Mutação , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia
18.
Phys Rev Lett ; 107(6): 062502, 2011 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-21902316

RESUMO

A benchmark experiment on (208)Pb shows that polarized proton inelastic scattering at very forward angles including 0° is a powerful tool for high-resolution studies of electric dipole (E1) and spin magnetic dipole (M1) modes in nuclei over a broad excitation energy range to test up-to-date nuclear models. The extracted E1 polarizability leads to a neutron skin thickness r(skin) = 0.156(-0.021)(+0.025) fm in (208)Pb derived within a mean-field model [Phys. Rev. C 81, 051303 (2010)], thereby constraining the symmetry energy and its density dependence relevant to the description of neutron stars.

19.
Nat Med ; 5(2): 226-30, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9930873

RESUMO

Liver cirrhosis is the irreversible end result of fibrous scarring and hepatocellular regeneration, characterized by diffuse disorganization of the normal hepatic structure of regenerative nodules and fibrotic tissue. It is associated with prominent morbidity and mortality, and is induced by many factors, including chronic hepatitis virus infections, alcohol drinking and drug abuse. Hepatocyte growth factor (HGF), originally identified and cloned as a potent mitogen for hepatocytes, shows mitogenic, motogenic and morphogenic activities for a wide variety of cells. Moreover, HGF plays an essential part in the development and regeneration of the liver, and shows anti-apoptotic activity in hepatocytes. In a rat model of lethal liver cirrhosis produced by dimethylnitrosamine administrations, repeated transfections of the human HGF gene into skeletal muscles induced a high plasma level of human as well as enodogenous rat HGF, and tyrosine phosphorylation of the c-Met/HGF receptor. Transduction with the HGF gene also suppressed the increase of transforming growth factor-beta1 (TGF-beta1), which plays an essential part in the progression of liver cirrhosis, inhibited fibrogenesis and hepatocyte apoptosis, and produced the complete resolution of fibrosis in the cirrhotic liver, thereby improving the survival rate of rats with this severe illness. Thus, HGF gene therapy may be potentially useful for the treatment of patients with liver cirrhosis, which is otherwise fatal and untreatable by conventional therapy.


Assuntos
Terapia Genética , Fator de Crescimento de Hepatócito/genética , Cirrose Hepática Experimental/terapia , Animais , Apoptose , Northern Blotting , Humanos , Fígado/patologia , Cirrose Hepática Experimental/patologia , Ratos , Ratos Sprague-Dawley , Transfecção , Fator de Crescimento Transformador beta/biossíntese
20.
J Biol Regul Homeost Agents ; 25(3): 341-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22023758

RESUMO

This study aims to determine the effects of different alkaline supplementations on high protein diet-induced abnormalities affecting bone metabolism in rats which were also undergoing physical exercise of moderate intensity. Sixty elderly Sprague-Dawley rats were randomly divided into four groups of 10 rats each and treated for 16 weeks as follows: baseline control group fed normal food (C); acidic high-protein diet supplemented group (chronic acidosis, CA group), bicarbonate-based alkaline formula (Basenpulver, Named, Italy) supplemented chronic acidosis (BB-CA) and citrate-based alkaline supplement (CB-CA). Throughout the supplementation period, rats were put on a treadmill training mimicking a moderate level of exercise. In the CA group, 24-hour urinary calcium (Ca) and phosphorus (P) excretion were increased over 30 percent (p<0.05 vs normal diet controls). However serum Ca was not significantly changed. Femural and tibial BMD and BMC was significantly decreased in the CA group (p<0.05) but both alkaline supplementations prevented such phenomenon (p<0.05 vs CA), without significant difference between the two formulations although the BB-CA group showed significantly more preserved trabecular bone volume (p<0.05 vs CB-CA group). An increased level of over 50 percent of urinary Dpd observed in the CA group (p<0.001) was reverted to normal by both supplementations (p<0.001 vs CA group). The same applied to urinary net acid excretion (p<001) with BB-supplementation performing better than CB-supplementation (p<0.05). Moreover, while the latter did not modify Nterminal telopeptide value, BB-supplementation significantly normalized this parameter (p<0.05 vs CA group) which exercise and acidic protein diet had modified (p<0.01 vs control diet). Overall, the present study shows that a bicarbonate-based alkaline formula, when administered to a dose amenable to clinical use, may significantly protect bone structure in exercising aged animals to a greater extent than a quali/quantitavely similar citrate-based formula.


Assuntos
Acidose/sangue , Acidose/urina , Envelhecimento , Bicarbonatos/farmacologia , Osso e Ossos/metabolismo , Cálcio/sangue , Cálcio/urina , Citratos/farmacologia , Suplementos Nutricionais , Fósforo , Condicionamento Físico Animal , Acidose/etiologia , Álcalis/farmacologia , Animais , Doença Crônica , Proteínas Alimentares/farmacologia , Masculino , Fósforo/sangue , Fósforo/urina , Ratos , Ratos Sprague-Dawley
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