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1.
J Infect Chemother ; 30(8): 757-767, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38432559

RESUMO

BACKGROUND: Mycobacterium abscessus species (MABS) is now a most virulent rapidly growing mycobacteria (RGM), and the rapid increase of MABS was recently observed worldwide, including in Japan. Thus, we gathered evidences of the presence of pulmonary MABS in Japanese population from Japanese articles. METHODS: we searched studies that addressed the isolation of pulmonary non-tuberculous Mycobacteria (NTM) or MABS from clinical respiratory specimens in Japan. RESULTS: the ratio of MABS to NTM was 3.04% (95% confidence interval [CI]: 2.51-3.68), found using the meta-analysis of single proportions. The estimated mean age of patients infected with MABS was 67.72 years (95% CI: 65.41-70.02), found using the meta-analysis of single means. The estimated proportion of females, never smoker, and the co-infection with Mycobacterium avium complex (MAC) was 66.75% (95% CI: 59.23-73.50), 67.57% (95% CI: 62.43-72.32), and 36.74% (95% CI: 25.30-49.90), respectively. The characteristics of MABS in Japan were considerably different from that in Europe and United States from the perspective of age, gender, and complications, wherein the patients in these countries tended to be younger, had lower number of females, and had more occurrences of hereditary diseases, including cystic fibrosis (CF). CONCLUSION: we hypothesized that the characteristics of MABS in the Japanese were involved in those of non-CF MABS, and the distribution of gender and age of MABS were similar to that of MAC in the Japanese.


Assuntos
Infecções por Mycobacterium não Tuberculosas , Mycobacterium abscessus , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Coinfecção/epidemiologia , Coinfecção/microbiologia , População do Leste Asiático , Japão/epidemiologia , Mycobacterium abscessus/isolamento & purificação , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Infecções por Mycobacterium não Tuberculosas/microbiologia , Fatores Sexuais , Pneumopatias/microbiologia
3.
Respirol Case Rep ; 10(2): e0896, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35003752

RESUMO

Dendriform pulmonary ossification (DPO) is a rare condition characterized by heterotopic bone production of unknown origin within the pulmonary tissue. Many cases are asymptomatic with slow progression and are often diagnosed incidentally during autopsy. Thus, only few cases are diagnosed while the patient is still alive since surgical lung biopsy is often needed for pathological diagnosis. This is the case of a 37-year-old man treated at our hospital due to abnormal findings on chest x-ray without any symptoms. His high-resolution computed tomography revealed diffuse reticular shadows and micronodules, consistent with calcification. He underwent transbronchial lung cryobiopsy (TBLC) and was diagnosed with idiopathic DPO based on pathological findings. To our knowledge, this is the first reported case of DPO diagnosed using TBLC. TBLC can be a useful yet minimally invasive diagnostic tool to diagnose DPO and other interstitial lung diseases.

4.
Drug Des Devel Ther ; 15: 223-230, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33500614

RESUMO

PURPOSE: The INPULSIS-ON study suggested the safety and tolerability of long-term nintedanib treatment for idiopathic pulmonary fibrosis (IPF). However, there are no real-world studies on long-term nintedanib treatment. The main aim of the study was to investigate the efficacy and the tolerability of long-term treatment with nintedanib for IPF in clinical practice. PATIENTS AND METHODS: This retrospective study enrolled 104 IPF patients who underwent treatment with nintedanib. Among these patients, 51 were able to receive nintedanib for more than 12 months (ie, treatment with nintedanib over 12 months was possible [P group]) and 53 were not able to receive nintedanib for more than 12 months (ie, treatment with nintedanib over 12 months was impossible [I group]). The tolerability and efficacy of nintedanib were compared between the two groups. RESULTS: In the I group, 29 patients were unable to continue nintedanib therapy because of adverse effects, including diarrhea and nausea/anorexia. In addition, 19 and four patients could not continue nintedanib treatment because of IPF progression and worsening of performance status (PS), respectively. One patient suddenly died during nintedanib treatment. The incidence of nausea/anorexia in the I group was significantly higher than in the P group (49.06 vs 25.49%). The survival time was significantly longer in the P group than in the I group (35 vs 12 months). The decline in forced vital capacity was significantly larger in the I group than in the P group (165 vs 10 mL/year). Poor PS at nintedanib initiation was the only significant risk factor for nintedanib treatment discontinuation over 12 months. Finally, the survival time was significantly longer in patients with good PS than in those with poor PS (27 vs 13 months). CONCLUSION: Poor PS can result in discontinuation of nintedanib after 12 months. Long-term nintedanib treatment may be effective for survival.


Assuntos
Fibrose Pulmonar Idiopática/tratamento farmacológico , Indóis/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Fibrose Pulmonar Idiopática/diagnóstico , Indóis/administração & dosagem , Indóis/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
5.
Thorac Cancer ; 12(5): 715-719, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33475256

RESUMO

To date, several studies have described the mechanism of resistance to first- or second-generation anaplastic lymphoma kinase (ALK) inhibitors. Secondary ALK mutations, ALK gene amplification, and other bypass signal activations (i.e., KRAS mutation, EGFR mutation, amplification of KIT, and increased autophosphorylation of EGFR) are known as resistance mechanisms. However, little has been previously reported on acquired resistance mechanisms to lorlatinib. Here, we report a case of a patient with ALK-positive lung adenocarcinoma that acquired resistance to lorlatinib during treatment for brain metastasis and showed histological transformation to squamous cell carcinoma with MET amplification. We also review the previous literature on the resistance mechanism to ALK inhibitors.


Assuntos
Adenocarcinoma/tratamento farmacológico , Aminopiridinas/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Lactamas/uso terapêutico , Pirazóis/uso terapêutico , Adenocarcinoma/patologia , Aminopiridinas/farmacologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Lactamas/farmacologia , Pessoa de Meia-Idade , Pirazóis/farmacologia
6.
Nucl Med Commun ; 41(11): 1189-1198, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32796454

RESUMO

OBJECTIVE: To semiquantitatively estimate fluorine-18-fluorodeoxyglucose (FDG) uptake in primary lung cancer cells using dynamic and dual-time-point (DTP) PET/computed tomography (PET/CT) to obtain a diagnostic index for lymph node metastasis. METHODS: Forty-five patients with lung cancer underwent dynamic and DTP PET/CT examinations. All primary lesions and lymph node metastases were evaluated pathologically. At each time phase, we assessed the maximum standardised uptake value (SUVmax), metabolic tumour volume (MTV) and total lesion glycolysis (TLG) of the primary tumours. We investigated the relationship between semiquantitative index and the presence of lymph node metastasis for each case and for all cases satisfying indications for segmentectomy. In cases with lymph node metastasis, we assessed the SUVmax of pathologically proven metastatic lymph nodes and nonmetastatic lymph nodes in each dynamic phase for evaluating temporal change. RESULTS: Among 45 patients, 15 had 17 lymph node metastasis. SUVmax, MTV and TLG of primary tumours at each time phase were significantly associated with lymph node metastasis (P < 0.05). In receiver operating characteristic analysis, dynamic second and third phases showed high diagnostic ability for lymph node metastasis. The temporal change in SUVmax in the dynamic phase between primary tumours and metastatic lymph nodes were significantly different (P = 0.065). The temporal change in SUVmax was significantly lower in nonmetastatic lymph nodes than in primary tumours and metastatic lymph nodes (P < 0.0001). CONCLUSIONS: Semiquantitative assessment of FDG uptake in dynamic second and third phases and the assessment of temporal changes in SUVmax on dynamic PET/CT scans were important predictors in diagnosing lymph node metastasis.


Assuntos
Fluordesoxiglucose F18/metabolismo , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Adulto , Idoso , Idoso de 80 Anos ou mais , Transporte Biológico , Feminino , Glicólise , Humanos , Neoplasias Pulmonares/metabolismo , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Carga Tumoral
7.
Respir Res ; 20(1): 287, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31852459

RESUMO

BACKGROUND: Acute exacerbation of chronic fibrosing idiopathic interstitial pneumonias (AE-IIPs) is associated with a high mortality rate. In 2016, an international working group proposed a revised diagnostic criteria for AE-IIPs, suggesting that it be classified as idiopathic or triggered. Many factors are known to trigger AE-IIPs, including surgery, infection, and drugs. However, it is unknown which AE-IIPs triggers have a worse prognosis. We aimed to investigate the prognosis of patients with various clinical types of AE-IIPs, particularly infection-triggered, non-infection triggered, and idiopathic AE-IIPs. METHODS: We retrospectively collected data from 128 chronic fibrosing IIPs (CF-IIPs) patients who were hospitalized by respiratory failure between April 2009 and March 2019 at Juntendo University Hospital. Among these patients, we evaluated 79 patients who developed AE-IIPs and 21 who developed pneumonia superimposed on CF-IIPs. Patients with AE-IIPs were classified into three types: idiopathic, infection-triggered, and non-infection-triggered AE-IIPs. We analyzed differences in patient characteristics, examination findings; level of serum markers, results of pulmonary function, and radiological findings, prior treatment for baseline CF-IIPs, and prognosis. We then evaluated the risk factor for early death (death within 30 days from the onset of AE-IIPs) associated with AE-IIPs. RESULTS: Among the patients who developed AE-IIPs, 34 were characterized as having idiopathic, 25 were characterized as having infection-triggered, and 20 were categorized as having non-infection-triggered AE-IIPs. Survival time for pneumonia superimposed on IIPs was significantly longer than that for any AE-IIPs. Survival time for bacterial pneumonia superimposed on CF-IIPs was significantly longer than that for AE-IIPs (for each idiopathic and all triggered IIPs). Thereafter, survival time for infection-triggered was significantly longer than for idiopathic or non-infection-triggered AE-IIPs. The mortality rate was significantly lower in infection-triggered AE-IIPs than in other types of AE-IIPs. Furthermore, the incidence of infection-triggered AE-IIPs in winter was significantly higher than that in other seasons. Moreover, the clinical AE-IIPs types and radiological findings at AE-IIP onset were significant risk factors for AE-IIPs-induced early death. CONCLUSIONS: Our findings suggest that patients with infection-triggered AE-IIPs can expect a better prognosis than can patients with other clinical types of AE-IIPs.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Doença Iatrogênica/epidemiologia , Pneumonias Intersticiais Idiopáticas/epidemiologia , Pulmão , Pneumonia Bacteriana/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/mortalidade , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/terapia , Feminino , Interações Hospedeiro-Patógeno , Humanos , Pneumonias Intersticiais Idiopáticas/diagnóstico , Pneumonias Intersticiais Idiopáticas/mortalidade , Pneumonias Intersticiais Idiopáticas/terapia , Incidência , Japão/epidemiologia , Pulmão/efeitos dos fármacos , Pulmão/microbiologia , Pulmão/cirurgia , Masculino , Pessoa de Meia-Idade , Pneumonia Bacteriana/diagnóstico , Pneumonia Bacteriana/mortalidade , Pneumonia Bacteriana/terapia , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Estações do Ano , Fatores de Tempo
8.
Ann Nucl Med ; 33(9): 689-696, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31201673

RESUMO

OBJECTIVE: 18F-FDG PET/CT is a hybrid imaging method widely used as a useful, noninvasive imaging modality for evaluating various neoplastic diseases. When assessing the tumor uptake, the liver and the mediastinal blood pool are often used as a reference region. In daily clinical practice, the 18F-FDG uptake in the liver sometimes appears to decrease on PET images of patients with malnutrition. The purpose of this study was to investigate whether or not the liver 18F-FDG uptake is decreased in patients with malnutrition. METHODS: We retrospectively analyzed 246 patients who underwent 18F-FDG PET/CT from January 2018 to June 2018 and whose blood serum albumin was measured within 1 month of PET/CT. We compared the liver uptake and mediastinal blood uptake of patients with low serum albumin level (< 4.0 g/dl) and hypoalbuminemia (< 3.5 g/dl) with those with a normal serum albumin level (≥ 4.0 g/dl). Correlations between the liver and mediastinal blood uptake and the serum albumin level were also calculated. RESULTS: The maximum standardized uptake value (SUVmax) and mean standardized uptake value (SUVmean) of the liver in 117 patients with low serum albumin were 3.1 ± 0.5 and 2.3 ± 0.3, respectively, while they were 2.9 ± 0.4, 2.0 ± 0.3 in 29 patients with hypoalbuminemia; these values were all significantly lower than the respective ones (3.4 ± 0.5, 2.5 ± 0.4) in 129 patients with normal serum albumin (all p < 0.001). The SUVmean of the mediastinal blood uptake in patients with hypoalbuminemia and normal serum albumin were 1.6 ± 0.2 and 1.7 ± 0.3, respectively (p = 0.053). The serum albumin level demonstrated a significantly positive, moderate correlation with the liver SUVmean, showing a regression line of y = 0.31x + 1.1 (r = 0.41, p < 0.001). CONCLUSION: The liver 18F-FDG uptake tended to decrease in patients with hypoalbuminemia. In the patients with malnutrition, the mediastinal blood pool may be a more stable reference than the liver for evaluating the tumor activity because hypoalbuminemia is considered to less strongly influence the mediastinal blood pool than that in the liver.


Assuntos
Fluordesoxiglucose F18/metabolismo , Hipoalbuminemia/complicações , Hipoalbuminemia/metabolismo , Fígado/metabolismo , Desnutrição/complicações , Idoso , Transporte Biológico , Feminino , Humanos , Hipoalbuminemia/diagnóstico por imagem , Fígado/diagnóstico por imagem , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Retrospectivos
9.
Cardiovasc Intervent Radiol ; 42(1): 69-77, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30039504

RESUMO

PURPOSE: To evaluate the accuracy of the virtual liver parenchymal perfusion area using a commercially available workstation and liver analysis software in conventional transarterial chemoembolization (cTACE) for hepatocellular carcinoma (HCC). MATERIALS AND METHODS: This method was retrospectively applied to 29 treated HCCs in 23 patients. The virtual embolic area (VEA) was estimated based on cone beam computed tomography during hepatic arteriography using a commercially available workstation and liver analysis software by two observer groups (group A: experts; group B: semi-experts). The real embolic area (REA) was defined as the area where iodized oil accumulated on computed tomography at 1 week after cTACE. The REA was estimated by each of the two groups, and the mean REA between the groups (mREA) was used as a standard reference. Agreement of volume and cross-sectional area in three orthogonal planes between the VEA and mREA were analyzed using intraclass correlation coefficients (ICCs) and Bland-Altman plots. RESULTS: The ICCs for volume between VEA and mREA were 0.97 and 0.88 for groups A and B, respectively, and those for cross-sectional area were 0.94 and 0.88 for the axial plane, 0.95 and 0.83 for the coronal plane, and 0.87 and 0.74 for the sagittal plane, respectively. Thus, the overall agreement was excellent, except for the sagittal imaging plane in group B. CONCLUSION: This method using a commercially available workstation and liver analysis software can be useful for estimating the embolic area in cTACE.


Assuntos
Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/terapia , Terapia Assistida por Computador , Interface Usuário-Computador , Idoso , Angiografia , Angiografia Digital , Tomografia Computadorizada de Feixe Cônico/métodos , Óleo Etiodado , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/irrigação sanguínea , Recidiva Local de Neoplasia/terapia , Proibitinas , Estudos Retrospectivos , Software
10.
Toxicology ; 328: 84-92, 2015 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-25527144

RESUMO

The health effects of silver nanoparticles (AgNPs) have not been well investigated, despite AgNPs now being widely used in consumer products. We investigated the metabolic behavior and toxicity of AgNPs in comparison to silver nitrate (AgNO3) both in vivo and in vitro. AgNPs (20 nm diameter) suspended in 1% albumin solution or AgNO3 solution was injected into the mouse lung. Less than 1% of the initial dose of AgNPs and more than 7% of the initial dose of AgNO3 was recovered in the liver 4h after administration, suggesting that the ionic form of silver was absorbed by the lung tissue and entered the systemic circulation more efficiently than AgNPs. The pro-inflammatory cytokine, IL-1ß, and neutrophils in bronchoalveolar lavage fluid (BALF) increased following intratracheal instillation of AgNPs or AgNO3. AgNO3 recruited more neutrophils in the alveolar space than did AgNPs. In the in vitro study, AgNO3 was more cytotoxic than 20, 60, or 100 nm diameter AgNPs in a mouse macrophage cell line (J774.1). To investigate the intracellular distribution of Ag in detail, J774.1 cells were exposed to AgNO3 or 20 nm AgNPs and the distribution of Ag to cytosolic proteins was investigated using HPLC-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). Ag was mainly distributed to metallothioneins (MT) and to high molecular weight proteins in AgNO3- and AgNPs-exposed cells, respectively. Confocal laser microscopic examination of LysoTracker(®)-labeled cells indicated that AgNPs were colocalized with lysosomes in J774.1 cells. These results suggest that AgNPs were transported to lysosomes and only gradually dissolved in the macrophages, causing milder inflammatory stimulation in the mouse lung compared to AgNO3.


Assuntos
Pulmão/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Nitrato de Prata/toxicidade , Animais , Transporte Biológico , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Mediadores da Inflamação/metabolismo , Exposição por Inalação/efeitos adversos , Interleucina-1beta/metabolismo , Fígado/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Metalotioneína/metabolismo , Camundongos Endogâmicos ICR , Peso Molecular , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Tamanho da Partícula , Nitrato de Prata/metabolismo , Fatores de Tempo
11.
Chem Pharm Bull (Tokyo) ; 61(12): 1228-38, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24292785

RESUMO

Solid-state characterization plays a vital role in lead optimization and candidate selection with the appropriate physicochemical properties for proper oral dosage formulation. Aqueous solubility is an important parameter in the successful development of oral dosage formulation since poor aqueous solubility limits absorption. In this study, we summarized an efficient approach using a small amount of sample for solid-state characterization, including thermodynamic solubility, which is defined as physicochemical profiling. By using the physicochemical profiling results of 75 anti-cancer drugs and clinical candidates, we examined the relationship between thermodynamic solubility and molecular structural parameters and assessed the effects of thermodynamic solubility on pharmacokinetic profile for rational soluble drug design. The Log DpH 7.4, aromatic ring count, and hydrogen bond count were good indicators for predicting sparingly soluble compounds that increase the lattice energy because of π-π stacking and hydrogen bonds, resulting in lowered thermodynamic solubility. The level of thermodynamic solubility in simulated intestinal fluid (pH 6.8) in the presence and absence of bile acid, which is required for minimal acceptable bioavailability (>30%), was 1 µg/mL and 10 µg/mL, respectively. Physicochemical profiling, which includes thermodynamic solubility considering its solid-state properties, contributes to rational lead optimization and efficient candidate selection for drug development.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacocinética , Descoberta de Drogas/métodos , Administração Oral , Animais , Antineoplásicos/administração & dosagem , Cristalização , Masculino , Neoplasias/tratamento farmacológico , Ratos , Ratos Sprague-Dawley , Solubilidade , Termodinâmica
12.
Toxicology ; 305: 20-9, 2013 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-23333424

RESUMO

Silver (Ag) possesses antibacterial activity and has been used in wound dressings and deodorant powders worldwide. However, the metabolic behavior and biological roles of Ag in mammals have not been well characterized. In the present study, we exposed human bronchial epithelial cells (BEAS-2B) to AgNO3 and investigated uptake and intracellular distribution of Ag, expression of metallothionein (MT), generation of reactive oxygen species (ROS), and changes in mitochondrial respiration. The culture medium concentration of Ag decreased with time and stabilized at 12h. The concentration of both Ag and MT in the soluble cellular fraction increased up to 3h and then decreased, indicating that cytosolic Ag relocated to the insoluble fraction of the cells. The levels of mRNAs for the major human MT isoforms MT-I and MT-II paralleled with the protein levels of Ag-MT. The intensity of fluorescence derived from ROS was elevated in the mitochondrial region at 24h. Ag decreased mitochondrial oxygen consumption in a dose-dependent manner and the activity of mitochondrial complex I-IV enzymes was significantly inhibited following exposure to Ag. In a separate experiment, we found that hydrogen peroxide (H2O2) at concentrations as low as 0.001% (equivalent to the concentration of H2O2 in Ag-exposed cells) removed Ag from MT. These results suggest MT was decomposed by cytosolic H2O2, and then Ag released from MT relocated to insoluble cellular fractions and inhibited electron chain transfer of mitochondrial complexes, which eventually led to cell damage.


Assuntos
Anti-Infecciosos Locais/toxicidade , Brônquios/metabolismo , Transporte de Elétrons/fisiologia , Células Epiteliais/metabolismo , Metalotioneína/metabolismo , Mitocôndrias/metabolismo , Nitrato de Prata/toxicidade , Brônquios/citologia , Brônquios/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cobre/metabolismo , Citocromos c/metabolismo , Citosol/química , Citosol/metabolismo , Transporte de Elétrons/efeitos dos fármacos , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Células Epiteliais/efeitos dos fármacos , Glutationa/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Metalotioneína/fisiologia , Mitocôndrias/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real , Prata/metabolismo , Zinco/metabolismo
13.
Nihon Eiseigaku Zasshi ; 67(3): 383-9, 2012 May.
Artigo em Japonês | MEDLINE | ID: mdl-22781012

RESUMO

Silver (Ag) possesses a well-known antibacterial activity and has been used for medical treatment and cosmetics such as wound dressing and deodorant powders. Occupational Safety and Health Administration (OSHA) and Mine Safety and Health Administration (MSHA) proposed that the permissible exposure limit (PEL) for both metallic and most soluble Ag compounds should be 0.01 mg/m3. Argyria and argyrosis are known to be caused by deposition of insoluble Ag in the dermis and cornea/conjunctiva. However, the metabolic behavior and biological roles of Ag have not been well characterized in mammals. Ag can be absorbed into the systemic circulation from drinking water, and also through parenteral routes such as inhalation and dermal exposure. Experimental studies have demonstrated that Ag+ induces and binds to metallothionein I and II (MTs), which are cysteine-rich proteins, in cells. MTs are major cytoplasmic metal binding proteins and thereby reduce cellular damage caused by toxic heavy metals including Ag. Profiles of Ag distribution in MTs and other Ag-binding proteins can be determined using high performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS). This technique directly provides information on the intracellular behavior of Ag, which is important for elucidating the mechanism underlying Ag toxicity. Silver nanoparticles (AgNPs) are also commercially used mainly as antimicrobial agents. Despite the widespread use of AgNPs, relatively few studies have been undertaken to evaluate the health effects of AgNP exposure. In the present paper, we discuss the absorption, toxicodynamics, and metabolism of both Ag and AgNPs in mammals and their health effects.


Assuntos
Exposição Ambiental , Prata/toxicidade , Animais , Humanos , Metalotioneína/análise , Nanopartículas/toxicidade , Prata/farmacocinética
14.
J Craniofac Surg ; 21(5): 1443-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20818256

RESUMO

The cranial neural crest cells contribute extensively to the formation of skeletogenic mesenchyme in the head and neck. Hes1 functions as a repressor of basic helix-loop-helix transcription factors and is implicated in controlling the maintenance of undifferentiated cells and the timing of cell differentiation. We show here that Hes1 homozygous null mutant mice exhibit multiple craniofacial malformations including calvaria agenesis, defective anterior cranial base, shortened maxilla and mandible, and abnormal palate and tongue. In the null mutant cranium, the calvarial bones, meninges including the dura mater and skin were not formed, and the brain was therefore exposed without the outer cover. The defective anterior cranial base in the mutants was attributable to the lack of presphenoid bone and the flexed cranial base angle, which was in contrast with the flat cranial base of wild-type mice. Furthermore, in the null mutants, palatal shelf growth was impaired because of the early elevation of the palatal shelves, resulting in a narrow palate and oral cavity, which were consistently associated with a small size of the tongue. These craniofacial anomalies could be the result of the defective development of neural crest cells. Taken together, it is supposed that Hes1 signaling plays an essential role in regulating the development of various craniofacial structures derived from the cranial neural crest cells.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Anormalidades Craniofaciais/metabolismo , Proteínas de Homeodomínio/fisiologia , Crista Neural/citologia , Palato/embriologia , Crânio/embriologia , Animais , Camundongos , Morfogênese/fisiologia , Crista Neural/fisiologia , Palato/anormalidades , Fenótipo , Transdução de Sinais , Crânio/anormalidades , Fatores de Transcrição HES-1
15.
Cell Tissue Res ; 340(3): 509-21, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20431921

RESUMO

The hypophyseal pars tuberalis surrounds the median eminence and infundibular stalk of the hypothalamus as thin layers of cells. The pars tuberalis expresses MT1 melatonin receptor and participates in mediating the photoperiodic secretion of pituitary hormones. Both the rostral tip of Rathke's pouch (pars tuberalis primordium) and the pars tuberalis expressed alphaGSU mRNA, and were immunoreactive for LH, chromogranin A, and TSHbeta in mice. Hes genes control progenitor cell differentiation in many embryonic tissues and play a crucial role for neurulation in the central nervous system. We investigated the Hes1 function in outgrowth and differentiation of the pars tuberalis by using the markers for the pars tuberalis. In homozygous Hes1 null mutant embryos, the rostral tip was formed in the basal-ventral part of Rathke's pouch at embryonic day (E)11.5 as well as in wild-type embryos. In contrast to the wild-type, the rostral tip of null mutants could not extend rostrally with age; it remained in the low extremity of Rathke's pouch during E12.5-E13.5 and disappeared at E14.5, resulting in lack of the pars tuberalis. Development of the ventral diencephalon was impaired in the null mutants at early stages. Rathke's pouch, therefore, could not link with the nervous tissue and failed to receive inductive signals from the diencephalon. In a very few mutant mice in which the ventral diencephalon was partially sustained, some pars tuberalis cells were distributed around the hypoplastic infundibulum. Thus, Hes1 is required for development of the pars tuberalis and its growth is dependent on the ventral diencephalon.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Homeodomínio/metabolismo , Hipófise/citologia , Hipófise/metabolismo , Animais , Biomarcadores/metabolismo , Diencéfalo/metabolismo , Diencéfalo/patologia , Embrião de Mamíferos/citologia , Regulação da Expressão Gênica , Subunidade alfa de Hormônios Glicoproteicos/genética , Subunidade alfa de Hormônios Glicoproteicos/metabolismo , Camundongos , Camundongos Mutantes , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição HES-1
16.
Cell Tissue Res ; 317(3): 279-88, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15300491

RESUMO

To clarify whether the common alpha-subunit of glycoprotein hormones is involved in photic signal transduction, alpha-subunit mRNA levels in the pars tuberalis (PT) of both hamsters and chickens were estimated at different time points of the day/night cycle by laser capture microdissection (LCM) and real-time quantitative polymerase chain reaction (PCR). Distinct diurnal rhythms were found for alpha-subunit mRNA expression in both species. In the hamster PT, alpha-subunit mRNA levels gradually increased during the dark phase; the diurnal peak was found at time (ZT) 21. The lowest value was obtained at ZT 5 during the day. In the chicken PT, alpha-subunit mRNA levels were maintained at a low constant level at night between ZT 13 and 21. Thus, alpha-subunit mRNA expression in the PT depends on the light-dark cycle and may be controlled by the pineal hormone melatonin. The effect of various photoperiods on the hamster PT was examined by real-time PCR, immunohistochemistry, and electron microscopy. In hamsters kept under short photoperiod (L/D=8 h:16 h) or complete darkness, a dramatic decrease of alpha-subunit mRNA level was induced, and the PT-specific cells accumulated glycogen-like particles and enlarged secretory granules. Under long photoperiods (L/D=16 h:8 h), however, the alpha-subunit mRNA level was elevated and the PT-specific cells exhibited highly active features, i.e., piles of lamellar cisternae of rough endoplasmic reticulum and well-developed Golgi complexes. The alpha-subunit synthesized by the PT-specific cells may therefore participate in the circadian and seasonal regulation of endocrine activities.


Assuntos
Galinhas/fisiologia , Ritmo Circadiano , Cricetinae/fisiologia , Subunidade alfa de Hormônios Glicoproteicos/biossíntese , Adeno-Hipófise/metabolismo , RNA Mensageiro/metabolismo , Animais , Subunidade alfa de Hormônios Glicoproteicos/genética , Técnicas Imunoenzimáticas , Adeno-Hipófise/ultraestrutura , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Biol Reprod ; 70(2): 356-63, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14561644

RESUMO

The beta subunits of the two pituitary gonadotropins LH and FSH and of thyroid-stimulating hormone (TSH) were cloned from Australian lungfish (Neoceratodus forsteri) pituitary glands. These three glycoprotein hormone beta subunits possess the main characteristics common to their counterparts in other vertebrates. Taking advantage of the phylogenetic position of the lungfish, close to the root of tetrapods, a maximum parsimony tree was inferred from these new sequences and sequences from representatives of the diversity of vertebrates. The topology of the tree was imposed so that it reflected as closely as possible the real evolutionary history of the subunits. This tree was used to estimate the relative evolution rate of the three subunits in vertebrates. Cumulated amino acid substitutions from the basal subunit node (ancestral subunit sequence) to the species node were calculated and compared. It showed that a burst in evolutionary rate occurred for the LHbeta subunit in the tetrapod lineage sometime after the emergence of amphibians. The rate of evolution of the LHbeta subunit was particularly high throughout the radiation of mammals while FSH and TSHbeta subunits kept quite stable in this lineage. A burst in evolutionary rate was also observed for the FSHbeta subunit in the lineage leading to teleosts sometime after the emergence of chondrosteans and the dynamic of evolution was high throughout the radiation of teleosts. These results were consistent with data obtained from pairwise comparisons.


Assuntos
Evolução Molecular , Peixes/genética , Subunidade beta do Hormônio Folículoestimulante/genética , Hormônio Luteinizante Subunidade beta/genética , Hipófise/fisiologia , Sequência de Aminoácidos , Substituição de Aminoácidos/genética , Animais , Dados de Sequência Molecular , Filogenia , Vertebrados
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