RESUMO
AIM: To assess the utility of dynamic chest radiography (DCR) during the preoperative evaluation of pleural adhesions. MATERIALS AND METHODS: Sequential chest radiographs of 146 patients with lung cancer were acquired during forced respiration using a DCR system. The presence of pleural adhesions and their grades were determined by retrospective surgery video assessment (absent: 121, present: 25). The maximum inspiration to expiration lung area ratio was used as an index for air intake volume. A ratio of ≥0.65 was regarded as insufficient respiration. Two radiologists assessed the images for pleural adhesions based on motion findings. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were compared for each adhesion grade and patient group (patients with sufficient/insufficient respiration). Pearson's chi-squared test compared the group. Statistical significance was set at p<0.05. RESULTS: DCR correctly identified 22/25 patients with pleural adhesions, with 20 false-positive results (sensitivity, 88%; specificity, 83.5%; PPV, 52.4%; NPV, 97.12%). Although the diagnostic performances for the various adhesion grades were similar, specificity in patients with sufficient respiration increased to 93.9% (31/33), identifying all cases except for those with loose adhesions. CONCLUSIONS: DCR images revealed restricted and/or distorted motions in lung structures and structural tension in patients with pleural adhesions. DCR could be a useful technique for routine preoperative evaluation of pleural adhesions. Further development of computerised methods can assist in the quantitative assessment of abnormal motion findings.
Assuntos
Neoplasias Pulmonares , Doenças Pleurais , Humanos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/diagnóstico por imagem , Doenças Pleurais/diagnóstico por imagem , Radiografia , Estudos Retrospectivos , Sensibilidade e Especificidade , Aderências Teciduais/diagnóstico por imagemRESUMO
Cooperation is a strategy that has been adopted by groups of organisms to execute complex tasks more efficiently than single entities. Cooperation increases the robustness and flexibility of the working groups and permits sharing of the workload among individuals. However, the utilization of this strategy in artificial systems at the molecular level, which could enable substantial advances in microrobotics and nanotechnology, remains highly challenging. Here, we demonstrate molecular transportation through the cooperative action of a large number of artificial molecular machines, photoresponsive DNA-conjugated microtubules driven by kinesin motor proteins. Mechanical communication via conjugated photoresponsive DNA enables these microtubules to organize into groups upon photoirradiation. The groups of transporters load and transport cargo, and cargo unloading is achieved by dissociating the groups into single microtubules. The group formation permits the loading and transport of cargoes with larger sizes and in larger numbers over long distances compared with single transporters. We also demonstrate that cargo can be collected at user-determined locations defined by ultraviolet light exposure. This work demonstrates cooperative task performance by molecular machines, which will help to construct molecular robots with advanced functionalities in the future.
Assuntos
Cinesinas , Microtúbulos , DNA/metabolismo , Dineínas/metabolismo , Humanos , Microtúbulos/metabolismo , NanotecnologiaRESUMO
Both proto-oncogenic and tumor-suppressive functions have been reported for enhancer of zeste homolog 2 (EZH2). To investigate the effects of its inactivation, a mutant EZH2 lacking its catalytic domain was prepared (EZH2-dSET). In a mouse bone marrow transplant model, EZH2-dSET expression in bone marrow cells induced a myelodysplastic syndrome (MDS)-like disease in transplanted mice. Analysis of these mice identified Abcg2 as a direct target of EZH2. Intriguingly, Abcg2 expression alone induced the same disease in the transplanted mice, where stemness genes were enriched. Interestingly, ABCG2 expression is specifically high in MDS patients. The present results indicate that ABCG2 de-repression induced by EZH2 mutations have crucial roles in MDS pathogenesis.
Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/patologia , Animais , Modelos Animais de Doenças , Camundongos , Mutação/genéticaRESUMO
BACKGROUND: Implantation of Kerboull acetabular reinforcement cross-plates (Kerboull plate) carries a risk for injury to vascular structures and pelvic organs. To our knowledge, there is no study assessing anatomical assessment related to this risk with this specific design. Therefore, we performed a prospective study to answer the following four questions: 1) What is the minimum distance and angle between the plate and iliac vessels? 2) What is the distance between the plate and the inner cortex of the ilium? 3) What is the ratio of views with muscle tissue present on the inner surface of the ilium? 4) What are the boundaries of the safe zone for transacetabular screw fixation for a Kerboull plate? HYPOTHESIS: A safe zone for fixation screws would be defined by a narrow range of insertion angles. MATERIALS AND METHODS: This is a CT-based 3D templating prospective study. Simulations were performed for 18 patients fitted with a Kerboull plate. An original Kerboull plate (Stryker, Mahwah, NJ, USA) was placed at a 45° abduction angle relative to the X-axis (alignment A) and the palette was placed vertically to the X-axis (alignment B). We measured the distance from the centre of the plate to the inner surface of the cortex of the ilium, the shortest distance to vessels and the angle of existing vessels, and the ratio of muscles on the inner surface of the ilium. RESULTS: The shortest distance to the vascular structures increased with increasing angle of insertion of the fixation screws, 85.8±12.1mm for A and 111.4±12.0mm for B at 45°. The distance to the inner cortex was further increased for screws inserted in posterior direction. At insertion angles ≥40°, the screws passed through muscle before invading the pelvis in most cases. However, at anterior-posterior angle (AP angles) ≤-10°, the risk of direct insertion of screws into the sacroiliac joint increased. DISCUSSION: The safe zone for transacetabular screws would be insertion at an angle≥40°, with an AP angle between 0° and -10° (slight posterior direction). LEVEL OF EVIDENCE: Level IV prospective diagnostic study.
Assuntos
Pontos de Referência Anatômicos/diagnóstico por imagem , Artroplastia de Quadril/métodos , Parafusos Ósseos , Implantação de Prótese/métodos , Tomografia Computadorizada por Raios X , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Adulto , Idoso , Artroplastia de Quadril/efeitos adversos , Placas Ósseas , Parafusos Ósseos/efeitos adversos , Simulação por Computador , Feminino , Fixação Interna de Fraturas , Humanos , Artéria Ilíaca/diagnóstico por imagem , Artéria Ilíaca/lesões , Veia Ilíaca/diagnóstico por imagem , Veia Ilíaca/lesões , Ílio/diagnóstico por imagem , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Estudos Prospectivos , Articulação Sacroilíaca/lesõesRESUMO
Mutations in ASXL1 are frequent in patients with myelodysplastic syndrome (MDS) and are associated with adverse survival, yet the molecular pathogenesis of ASXL1 mutations (ASXL1-MT) is not fully understood. Recently, it has been found that deletion of Asxl1 or expression of C-terminal-truncating ASXL1-MTs inhibit myeloid differentiation and induce MDS-like disease in mice. Here, we find that SET-binding protein 1 (SETBP1) mutations (SETBP1-MT) are enriched among ASXL1-mutated MDS patients and associated with increased incidence of leukemic transformation, as well as shorter survival, suggesting that SETBP1-MT play a critical role in leukemic transformation of MDS. We identify that SETBP1-MT inhibit ubiquitination and subsequent degradation of SETBP1, resulting in increased expression. Expression of SETBP1-MT, in turn, inhibited protein phosphatase 2A activity, leading to Akt activation and enhanced expression of posterior Hoxa genes in ASXL1-mutant cells. Biologically, SETBP1-MT augmented ASXL1-MT-induced differentiation block, inhibited apoptosis and enhanced myeloid colony output. SETBP1-MT collaborated with ASXL1-MT in inducing acute myeloid leukemia in vivo. The combination of ASXL1-MT and SETBP1-MT activated a stem cell signature and repressed the tumor growth factor-ß signaling pathway, in contrast to the ASXL1-MT-induced MDS model. These data reveal that SETBP1-MT are critical drivers of ASXL1-mutated MDS and identify several deregulated pathways as potential therapeutic targets in high-risk MDS.
Assuntos
Proteínas de Transporte/genética , Transformação Celular Neoplásica/genética , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicas/genética , Proteínas Nucleares/genética , Proteínas Repressoras/genética , Adulto , Animais , Apoptose , Proteínas de Transporte/metabolismo , Diferenciação Celular , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Células HEK293 , Células HL-60 , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/mortalidade , Síndromes Mielodisplásicas/patologia , Proteínas Nucleares/metabolismo , Proteína Fosfatase 2/genética , Proteína Fosfatase 2/metabolismo , Proteólise , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais , Análise de Sobrevida , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , UbiquitinaçãoRESUMO
OBJECTIVE: To develop an augmented reality (AR) neuronavigation system with Web cameras and examine its clinical utility. METHODS: The utility of the system was evaluated in three patients with brain tumors. One patient had a glioblastoma and two patients had convexity meningiomas. Our navigation system comprised the open-source software 3D Slicer (Brigham and Women's Hospital, Boston, Massachusetts, USA), the infrared optical tracking sensor Polaris (Northern Digital Inc., Waterloo, Canada), and Web cameras. We prepared two different types of Web cameras: a handheld type and a headband type. Optical markers were attached to each Web camera. We used this system for skin incision planning before the operation, during craniotomy, and after dural incision. RESULTS: We were able to overlay these images in all cases. In Case 1, accuracy could not be evaluated because the tumor was not on the surface, though it was generally suitable for the outline of the external ear and the skin. In Cases 2 and 3, the augmented reality error was â¼2 to 3 mm. CONCLUSION: AR technology was examined with Web cameras in neurosurgical operations. Our results suggest that this technology is clinically useful in neurosurgical procedures, particularly for brain tumors close to the brain surface.
Assuntos
Neuroimagem/métodos , Neuronavegação/métodos , Procedimentos Neurocirúrgicos/métodos , Cirurgia Assistida por Computador/métodos , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Estudos de Viabilidade , Feminino , Glioblastoma/patologia , Glioblastoma/cirurgia , Humanos , Meningioma/patologia , Meningioma/cirurgia , Pessoa de Meia-Idade , Neuroimagem/instrumentação , Neuronavegação/instrumentação , Procedimentos Neurocirúrgicos/instrumentação , Cirurgia Assistida por Computador/instrumentação , Resultado do TratamentoRESUMO
OBJECTIVE: We retrospectively evaluated the effect of transpulmonary radiofrequency ablation (RFA) of liver tumours on the lung. METHODS: 16 patients (10 males and 6 females; mean age, 65.2 years) with 16 liver tumours (mean diameter 1.5 cm) underwent transpulmonary RFA under CT fluoroscopic guidance. The tumours were either hepatocellular carcinoma (n=14) or liver metastasis (n=12). All 16 liver tumours were undetectable with ultrasonography. The pulmonary function values at 3 months after transpulmonary RFA were compared with baseline (i.e. values before RFA). RESULTS: In 8 of 16 sessions, minor pulmonary complications occurred, including small pneumothorax (n=8) and small pleural effusion (n=1). In two sessions, major pulmonary complications occurred, including pneumothorax requiring a chest tube (n=2). These chest tubes were removed at 4 and 6 days, and these patients were discharged 7 and 10 days after RFA, respectively, without any sequelae. The pulmonary function values we evaluated were forced expiratory volume in 1 s (FEV1.0) and vital capacity (VC). The mean values of FEV1.0 before and 3 months after RFA were 2.55 l and 2.59 l, respectively; the mean values of VC before and 3 months after RFA were 3.20 l and 3.27 l, respectively. These pulmonary values did not show any significant worsening (p=0.393 and 0.255 for FEV1.0 and VC, respectively). CONCLUSION: There was no significant lung injury causing a fatal or intractable complication after transpulmonary RFA of liver tumours.
Assuntos
Carcinoma Hepatocelular/cirurgia , Ablação por Cateter/métodos , Neoplasias Hepáticas/cirurgia , Derrame Pleural/etiologia , Pneumotórax/etiologia , Idoso , Ablação por Cateter/efeitos adversos , Feminino , Fluoroscopia/efeitos adversos , Fluoroscopia/métodos , Volume Expiratório Forçado/efeitos da radiação , Humanos , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Derrame Pleural/fisiopatologia , Pneumotórax/fisiopatologia , Radiografia Intervencionista/efeitos adversos , Radiografia Intervencionista/métodos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/efeitos adversos , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Capacidade Vital/efeitos da radiaçãoAssuntos
Aortite/complicações , Aortite/terapia , Transplante de Células-Tronco Hematopoéticas , Leucemia Mielomonocítica Crônica/complicações , Leucemia Mielomonocítica Crônica/terapia , Adulto , Aortite/diagnóstico por imagem , Doenças Autoimunes/terapia , Doença Enxerto-Hospedeiro/complicações , Humanos , Masculino , Tomografia Computadorizada por Raios X , Transplante HomólogoRESUMO
The aim of this study was to analyze clinical aspects, hearing evolution and efficacy of clinical treatment of patients with sudden sensorineural hearing loss (SSNHL). This was a prospective clinical study of 136 consecutive patients with SSNHL divided into three groups after diagnostic evaluation: patients with defined etiology (DE, N = 13, 10%), concurrent diseases (CD, N = 63, 46.04%) and idiopathic sudden sensorineural hearing loss (ISSHL, N = 60, 43.9%). Initial treatment consisted of prednisone and pentoxifylline. Clinical aspects and hearing evolution for up to 6 months were evaluated. Group CD comprised 73% of patients with metabolic decompensation in the initial evaluation and was significantly older (53.80 years) than groups DE (41.93 years) and ISSHL (39.13 years). Comparison of the mean initial and final hearing loss of the three groups revealed a significant hearing improvement for group CD (P = 0.001) and group ISSHL (P = 0.001). Group DE did not present a significant difference in thresholds. The clinical classification for SSNHL allows the identification of significant differences regarding age, initial and final hearing impairment and likelihood of response to therapy. Elevated age and presence of coexisting disease were associated with a greater initial hearing impact and poorer hearing recovery after 6 months. Patients with defined etiology presented a much more limited response to therapy. The occurrence of decompensated metabolic and cardiovascular diseases and the possibility of first manifestation of auto-immune disease and cerebello-pontine angle tumors justify an adequate protocol for investigation of SSNHL.
Assuntos
Perda Auditiva Neurossensorial , Perda Auditiva Súbita , Adulto , Anti-Inflamatórios/uso terapêutico , Audiometria de Tons Puros , Limiar Auditivo , Quimioterapia Combinada , Perda Auditiva Neurossensorial/tratamento farmacológico , Perda Auditiva Neurossensorial/etiologia , Perda Auditiva Neurossensorial/fisiopatologia , Perda Auditiva Súbita/tratamento farmacológico , Perda Auditiva Súbita/etiologia , Perda Auditiva Súbita/fisiopatologia , Humanos , Pessoa de Meia-Idade , Pentoxifilina/uso terapêutico , Prednisona/uso terapêutico , Estudos Prospectivos , Resultado do Tratamento , Vasodilatadores/uso terapêuticoRESUMO
The aim of this study was to analyze clinical aspects, hearing evolution and efficacy of clinical treatment of patients with sudden sensorineural hearing loss (SSNHL). This was a prospective clinical study of 136 consecutive patients with SSNHL divided into three groups after diagnostic evaluation: patients with defined etiology (DE, N = 13, 10%), concurrent diseases (CD, N = 63, 46.04%) and idiopathic sudden sensorineural hearing loss (ISSHL, N = 60, 43.9%). Initial treatment consisted of prednisone and pentoxifylline. Clinical aspects and hearing evolution for up to 6 months were evaluated. Group CD comprised 73% of patients with metabolic decompensation in the initial evaluation and was significantly older (53.80 years) than groups DE (41.93 years) and ISSHL (39.13 years). Comparison of the mean initial and final hearing loss of the three groups revealed a significant hearing improvement for group CD (P = 0.001) and group ISSHL (P = 0.001). Group DE did not present a significant difference inthresholds. The clinical classification for SSNHL allows the identification of significant differences regarding age, initial and final hearing impairment and likelihood of response to therapy. Elevated age and presence of coexisting disease were associated with a greater initial hearing impact and poorer hearing recovery after 6 months. Patients with defined etiology presented a much more limited response to therapy. The occurrence of decompensated metabolic and cardiovascular diseases and the possibility of first manifestation of auto-immune disease and cerebello-pontine angle tumors justify an adequate protocol for investigation of SSNHL.
Assuntos
Adulto , Humanos , Pessoa de Meia-Idade , Perda Auditiva Neurossensorial , Perda Auditiva Súbita , Audiometria de Tons Puros , Limiar Auditivo , Anti-Inflamatórios/uso terapêutico , Quimioterapia Combinada , Perda Auditiva Neurossensorial/tratamento farmacológico , Perda Auditiva Neurossensorial/etiologia , Perda Auditiva Neurossensorial/fisiopatologia , Perda Auditiva Súbita/tratamento farmacológico , Perda Auditiva Súbita/etiologia , Perda Auditiva Súbita/fisiopatologia , Estudos Prospectivos , Pentoxifilina/uso terapêutico , Prednisona/uso terapêutico , Resultado do Tratamento , Vasodilatadores/uso terapêuticoRESUMO
BACKGROUND AND PURPOSE: A traditional Japanese herbal medicine, hochu-ekki-to, has been used for the symptomatic treatment of the common cold and to reduce the frequency of colds in patients with chronic obstructive pulmonary disease. However, the inhibitory effects of hochu-ekki-to on infection by rhinovirus (RV), the major cause of common colds, have not been studied. EXPERIMENTAL APPROACH: Human tracheal epithelial cells in culture were infected with a major group rhinovirus-RV14. Virus output and viral RNA were measured along with interleukin (IL)-1beta, IL-6, IL-8 and tumor necrosis factor (TNF)-alpha), mRNA for intercellular adhesion molecule (ICAM)-1 and acidic endosomes in cells. KEY RESULTS: RV14 infection increased virus titers, the content of cytokines in supernatants and RV14 RNA in the cells. Hochu-ekki-to decreased virus output, RV14 RNA in the cells, susceptibility to RV infection and supernatant cytokine concentrations after RV14 infection. Hochu-ekki-to reduced mRNA for ICAM-1, the receptor for RV14, the concentration of the soluble form of ICAM-1 and the number and fluorescence intensity of acidic endosomes in the cells, from which RV RNA enters into the cytoplasm, at RV14 infection. Glycyrrhizin, one of the chemical constituents of hochu-ekki-to, reduced supernatant virus titers dose-dependently. CONCLUSION AND IMPLICATIONS: Hochu-ekki-to inhibited RV14 infection by decreasing ICAM-1 and by blocking entry of viral RNA into the cytoplasm from the endosomes, in airway epithelial cells. Glycyrrhizin may be partly responsible for inhibition of RV infection by hochu-ekki-to. Hochu-ekki-to could modulate airway inflammation by reducing production of cytokines in RV infections.
Assuntos
Resfriado Comum/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Fitoterapia , Rhinovirus/efeitos dos fármacos , Células Cultivadas , Resfriado Comum/imunologia , Resfriado Comum/virologia , Citocinas/biossíntese , Endossomos/efeitos dos fármacos , Endossomos/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/imunologia , Células Epiteliais/virologia , Humanos , Concentração de Íons de Hidrogênio , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Viral/metabolismo , Rhinovirus/fisiologia , Traqueia/efeitos dos fármacos , Traqueia/imunologia , Traqueia/virologia , Replicação Viral/efeitos dos fármacosRESUMO
The aim of the study was to examine the effects of a mucolytic drug, carbocisteine, on rhinovirus (RV) infection in the airways. Human tracheal epithelial cells were infected with a major-group RV, RV14. RV14 infection increased virus titres and the cytokine content of supernatants. Carbocisteine reduced supernatant virus titres, the amount of RV14 RNA in cells, cell susceptibility to RV infection and supernatant cytokine concentrations, including interleukin (IL)-6 and IL-8, after RV14 infection. Carbocisteine reduced the expression of mRNA encoding intercellular adhesion molecule (ICAM)-1, the receptor for the major group of RVs. It also reduced the supernatant concentration of a soluble form of ICAM-1, the number and fluorescence intensity of acidic endosomes in the cells before RV infection, and nuclear factor-kappaB activation by RV14. Carbocisteine also reduced the supernatant virus titres of the minor group RV, RV2, although carbocisteine did not reduce the expression of mRNA encoding a low density lipoprotein receptor, the receptor for RV2. These results suggest that carbocisteine inhibits rhinovirus 2 infection by blocking rhinovirus RNA entry into the endosomes, and inhibits rhinovirus 14 infection by the same mechanism as well as by reducing intercellular adhesion molecule-1 levels. Carbocisteine may modulate airway inflammation by reducing the production of cytokines in rhinovirus infection.
Assuntos
Anti-Infecciosos Locais/farmacologia , Antivirais/farmacologia , Carbocisteína/farmacologia , Células Epiteliais/virologia , Infecções por Picornaviridae/tratamento farmacológico , Rhinovirus/metabolismo , Traqueia/virologia , Idoso , Endossomos/metabolismo , Feminino , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Masculino , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Receptores de LDL/metabolismoRESUMO
Osteoprotegerin (OPG) is a recently identified member of the tumor necrosis factor (TNF) receptor superfamily that regulates bone mass through an inhibitory action on osteoclast differentiation and function. To determine its potential roles of OPG in pathological changes in bone metabolism caused by estrogen deficiency, we investigated effects of estrogen on OPG expression by a mouse stromal cell line, ST-2, in vitro. Treatment of ST-2 cells with 17beta-E(2) resulted in up-regulation of OPG expression at both the messenger RNA and protein levels. The effect was time and dose dependent and steroid specific. The stimulatory action of 17beta-E(2) on OPG expression appeared to be mediated by the estrogen receptor-alpha (ERalpha) subtype because stable overexpression of ERalpha, but not of ERbeta, enhanced the OPG induction by 17beta-E(2). Moreover, estrogen withdrawal after 5-day pretreatment, mimicking the event occurring in vivo at menopause, dramatically diminished the expression of OPG. These findings suggest that down-regulation of OPG after estrogen withdrawal contributes to the enhanced osteoclastic bone resorption and bone loss after menopause by enhancing RANK ligand-RANK system that lies downstream of a large number of bone-resorbing cytokines.
Assuntos
Estradiol/farmacologia , Expressão Gênica/efeitos dos fármacos , Glicoproteínas/genética , Receptores Citoplasmáticos e Nucleares/genética , Receptores de Estrogênio/fisiologia , Células Estromais/metabolismo , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Estradiol/administração & dosagem , Receptor alfa de Estrogênio , Glicoproteínas/análise , Humanos , Cinética , Camundongos , Osteoprotegerina , RNA Mensageiro/análise , Receptores Citoplasmáticos e Nucleares/análise , Receptores de Estrogênio/efeitos dos fármacos , Receptores do Fator de Necrose TumoralRESUMO
Hematologic malignancies such as multiple myeloma, adult T cell leukemia and malignant lymphoma are often complicated with bone lesions and/or hypercalcemia. The abnormal bone metabolism in these diseases are modified by co-existing cachexia, malnutrition, sex hormone deficiency and abnormal parathyroid function or by chemotherapy in a complex manner. Metabolic bone markers are not only clinically useful for evaluation and diagnosis of such bone abnormalities but may also be used to monitor the disease activity itself, particularly in multiple myeloma which almost inevitably involves bone destructive lesions.
RESUMO
Parathyroid hormone-related peptide (PTHrP) was initially discovered as a tumor-derived systemic factor which causes humoral hypercalcemia of malignancy. When overproduced and secreted by tumor cells, PTHrP acts on target organs such as bone and kidney to cause hypercalcemia through its 'PTH-like effects'. The hypercalcemic effects of PTHrP are attributed to its N-terminal portion (1-36) which shows a limited homology with PTH and is able to bind to the common PTH/PTHrP receptor. In contrast to such pathological effects as a humoral factor, PTHrP is now recognized as a locally active cytokine produced by a variety of tissues and cell types. Gene knockout experiments have revealed critical roles for PTHrP in a wide spectrum of physiological processes including chondrogenesis. It also significantly contributes to various pathological processes such as tumor metastasis to bone and bone destruction in arthropathies, acting as a bone-resorbing cytokine. Consistent with its divergent roles, regulation of PTHrP expression as well as its mode of action seems to be much more complex than its hormonal counterpart, PTH. In this article, we will briefly review the recent progress in our understanding of both physiological and pathological aspects of PTHrP biology, with a particular focus on its roles as a bone cytokine.
Assuntos
Doenças Ósseas/patologia , Osso e Ossos/fisiologia , Proteínas/fisiologia , Osso e Ossos/patologia , Humanos , Proteína Relacionada ao Hormônio Paratireóideo , Proteínas/química , Proteínas/metabolismoRESUMO
Myotonic dystrophy (MD) is characterized by myotonia and muscular dystrophy and cardiac involvement with tachy-arrhythmia is rarely encountered. We report a case of MD complicated with severe left ventricular hypofunction and incessant ventricular tachycardia (VT) with varying heart rates. The morphology of VT suggested that it originated from the right ventricular outflow tract, and electrophysiological study disclosed that the mechanism of VT was abnormal automaticity. Catheter ablation was performed to treat this VT. The patient had a cardiomyopathy with normal coronary arteries. The specimen of RV biopsy showed moderate hypertrophy, mild fat infiltration and slight fibrosis. These findings are histologically consistent with myotonic dystrophy.
Assuntos
Ablação por Cateter , Distrofia Miotônica/complicações , Taquicardia Ventricular/cirurgia , Bradicardia/etiologia , Eletrocardiografia , Feminino , Ventrículos do Coração/patologia , Humanos , Pessoa de Meia-Idade , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/etiologiaRESUMO
Although expression of the calcitonin (CT) receptor (CTR) decreases after CT binding, there has been no evidence that it occurs at the transcriptional level. In the present study we investigated the mechanism of CTR messenger RNA (mRNA) down-regulation by CT in mouse cocultures of bone marrow and osteoblasts. Ribonuclease protection analysis revealed that osteoclast-like cells purified from cocultures predominantly express the C1a isoform and do not express an appreciable amount of the brain-specific C1b mRNA (< 1% of C1a). Treatment of day 5 cocultures with CT caused a dose- and time-dependent decrease in the steady state level of C1a mRNA. This CT effect was mimicked by the cAMP agonists forskolin and (Bu)2cAMP. Prolonged suppression of C1a mRNA was observed after short treatment with CT, but not with (Bu)2cAMP, suggesting that persistent intracellular cAMP elevation is necessary for the prolonged CT effect. The half-life of the C1a mRNA in cocultures was 4-6 h and was not altered by CT or (Bu)2cAMP. Moreover, competitive RT-PCR analysis revealed that 1-h treatment with CT reduced the level of CTR heterogeneous nuclear RNA to 10% in a cycloheximide-independent manner. These results suggest that CT down-regulates C1a-CTR mRNA expression at least in part by a transcriptional mechanism, thereby contributing to the ligand-induced desensitization in cells of the osteoclast lineage.
Assuntos
Calcitonina/fisiologia , Osteoclastos/metabolismo , Isoformas de Proteínas/metabolismo , Receptores da Calcitonina/metabolismo , Transcrição Gênica , Animais , Células da Medula Óssea/metabolismo , Linhagem da Célula , Técnicas de Cocultura , Regulação para Baixo , Masculino , Camundongos , RibonucleasesRESUMO
Thyroid follicles in the lateral position of the neck are usually thought to represent the metastasis of thyroid carcinoma. Here we present a case of a 28-year-old woman with accessory ectopic thyroid associated with Graves' disease. Despite a history of Graves' disease poorly controlled with large dose propylthiouracil she was found to be pregnant and artificial abortion was planned. Thyroid scintigraphy was carried out, which indicated an uptake into the region above the left lobe as well as into both lobes of the thyroid gland. In order to control hyperthyroidism and to exclude the possibility of metastasis, total thyroidectomy with tumor resection was performed before the artificial abortion. Pathological examinations of the thyroid gland indicated findings compatible with Graves' disease. The lateral neck mass was revealed to be composed of nonneoplastic thyroid tissue, showing similar histological findings to those of the goiter, which were consistent with Graves' disease. Taken together with several previous reports, it appears that there are some cases with lateral ectopic thyroid tissue, whose pathogenetic mechanism remains to be elucidated.