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One of the major global health and welfare issues is the treatment of obesity and associated metabolic disorders, such as type 2 diabetes mellitus and nonalcoholic fatty liver disease. Obesity, caused by the excessive accumulation of triglycerides in adipose tissues, induces adipocyte dysfunction, followed by inflammation, in adipose tissues and lipotoxicity in nonadipose tissues. Several studies have shown that obesity and glucose homeostasis are influenced by sphingolipid mediators, including ceramide and sphingosine 1-phosphate (S1P). Cellular accumulation of ceramide impairs pancreatic ß-cell survival, confers insulin resistance in the liver and the skeletal muscle, and deteriorates adipose tissue inflammation via unknown molecular mechanisms. The roles of S1P are more complicated, because there are five cell-surface S1P receptors (S1PRs: S1P1-5) which have altered functions, different cellular expression patterns, and inapparent intracellular targets. Recent findings, including those by our group, support the notable concept that the pharmacological activation of S1P1 or S1P3 improves obesity and associated metabolic disorders, whereas that of S1P2 has the opposite effect. In addition, the regulation of S1P production by sphingosine kinase (SphK) is an essential factor affecting glucose homeostasis. This review summarizes the current knowledge on SphK/S1P/S1PR signaling in and against obesity, insulin resistance, and associated disorders.
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Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Lisofosfolípidos , Esfingosina/análogos & derivados , Humanos , Obesidad , Ceramidas , Inflamación , Homeostasis , GlucosaRESUMEN
Considering the importance of elucidating the heat transfer in living cells, we evaluated the thermal conductivity κ and conductance G of hydrated protein through all-atom non-equilibrium molecular dynamics simulation. Extending the computational scheme developed in earlier studies for spherical protein to cylindrical one under the periodic boundary condition, we enabled the theoretical analysis of anisotropic thermal conduction and also discussed the effects of protein size correction on the calculated results. While the present results for myoglobin and green fluorescent protein (GFP) by the spherical model were in fair agreement with previous computational and experimental results, we found that the evaluations for κ and G by the cylindrical model, in particular, those for the longitudinal direction of GFP, were enhanced substantially, but still keeping a consistency with experimental data. We also studied the influence by salt addition of physiological concentration, finding insignificant alteration of thermal conduction of protein in the present case.
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Simulación de Dinámica Molecular , Agua , Conductividad Térmica , Proteínas Fluorescentes Verdes , MioglobinaRESUMEN
OBJECTIVES: To efficiently detect somatic UBA1 variants and establish a clinical scoring system predicting patients with pathogenic variants in VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome. METHODS: Eighty-nine Japanese patients with clinically suspected VEXAS syndrome were recruited [81 males and 8 females; median onset age (IQR) 69.3 years (62.1-77.6)]. Peptide nucleic acid-clamping PCR (PNA-PCR), regular PCR targeting exon 3 clustering UBA1 variants, and subsequent Sanger sequencing were conducted for variant screening. Partitioning digital PCR (pdPCR) or targeted amplicon deep sequencing (TAS) was also performed to evaluate the variant allele frequency (VAF). We developed our clinical scoring system to predict UBA1 variant-positive and negative patients and assessed the diagnostic value of our system using receiver operating characteristic (ROC) curve analysis. RESULTS: Forty patients with reported pathogenic UBA1 variants (40/89, 44.9%) were identified, including a case having a variant with VAF of 1.7%, using a highly sensitive method. Our clinical scoring system considering >50 years of age, cutaneous lesions, lung involvement, chondritis, and macrocytic anaemia efficiently predicted patients with UBA1 variants (the area under the curve for the scoring total was 0.908). CONCLUSIONS: Genetic screening with the combination of regular PCR and PNA-PCR detected somatic UBA1 variants with high sensitivity and specificity. Our scoring system could efficiently predict patients with UBA1 variants.
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BACKGROUND: Organic acids on the surface of human hands contribute to the barrier against transient pathogens. This is the first study to explore the synergistic contribution of lactic acid and other hand environment-related features on the antibacterial properties of the hand surface. MATERIALS AND METHODS: We estimated the contribution of fingerprint depth, skin pH, stratum corneum water content, skin temperature, and sweat rate of the hands to the infection barrier using an observational survey of 105 subjects. The relationship between each factor and the antibacterial activity of the hands was analyzed using Pearson's correlation coefficient. We performed molecular dynamics simulations to study the interaction between lactic acid and bacterial membranes. RESULTS: The amount of lactic acid on the hands and skin temperature contributed positively to the antimicrobial activity (r = 0.437 and P = 3.18 × 10-6 , r = 0.500 and P = 5.66 × 10-8 , respectively), while the skin pH contributed negatively (r = -0.471, P = 3.99 × 10-7 ). The predicted value of the combined antimicrobial effect of these parameters was [antimicrobial activity] = 0.21 × [lactic acid] - 0.25 × [skin pH] + 0.26 × [skin temperature] + 0.98. The coefficient of determination (R2 ) was 0.50. CONCLUSION: The increase in the amount of non-ionic lactic acid due to lower pH and improvement in the fluidity of the cell membrane due to higher temperatures enable the efficient transport of lactic acid into cells and subsequent antimicrobial activity. The proposed mechanism could help to develop an effective hand infection barrier technology.
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Mano , Ácido Láctico , Epidermis , Humanos , AguaRESUMEN
OBJECTIVES: Although transthyretin (TTR) is a nutritional indicator and is influenced by systemic inflammation, it may be a good prognostic indicator for cancer patients in palliative care settings. This study investigates the correlation between low TTR levels and survival among cancer patients in palliative care settings. METHODS: This was a sub-analysis of a prospective, multicenter cohort study. Patients who had advanced-stage cancer and who were newly referred to palliative care services were eligible to participate; however, those receiving anti-tumor therapy were excluded. Survival analyses were performed to clarify predictors of poor prognosis. RESULTS: A total of 144 patients were enrolled (45.1% female; median age, 72 years). Cox regression analysis revealed that low TTR levels (<10.9 mg/l) (hazard ratio 1.74, P = 0.025), poor muscle power (1.71, P = 0.045), and fatigue (1.89, P = 0.024) were predictors of poor prognosis. Median survival in patients with low TTR levels (<10.9 mg/l) was 26 days, which was significantly shorter than those with high TTR levels (≥10.9 mg/l) (50 days; P < 0.001). CONCLUSION: Low TTR levels may be indicators for poor prognosis among cancer patients in palliative care settings.
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Neoplasias/sangre , Neoplasias/mortalidad , Cuidados Paliativos , Prealbúmina/análisis , Anciano , Anciano de 80 o más Años , Pueblo Asiatico , Biomarcadores de Tumor/sangre , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Análisis de SupervivenciaRESUMEN
PURPOSE: Although corticosteroids are widely used to relieve anorexia, information regarding the factors predicting responses to corticosteroids remains limited. The purpose of the study is to identify potential factors predicting responses to corticosteroids for anorexia in advanced cancer patients. METHODS: Inclusion criteria for this multicenter prospective observational study were patients who had metastatic or locally advanced cancer and had an anorexia intensity score of 4 or more on a 0-10 Numerical Rating Scale (NRS). Univariate and multivariate analyses were conducted to identify the factors predicting ≥2-point reduction in NRS on day 3. RESULTS: Among 180 patients who received corticosteroids, 99 (55 %; 95 % confidence interval [CI], 47-62 %) had a response with ≥2-point reduction. Factors that significantly predicted responses were Palliative Performance Scale (PPS) > 40 and absence of drowsiness. In addition, factors that tended to be associated with ≥2-point reduction in NRS included PS 0-3, absence of diabetes mellitus, absence of peripheral edema, presence of lung metastasis, absence of peritoneal metastasis, baseline anorexia NRS of >6, presence of pain, and presence of constipation. A multivariate analysis showed that the independent factors predicting responses were PPS of >40 (odds ratio = 2.7 [95 % CI = 1.4-5.2]), absence of drowsiness (2.6 [1.3-5.0]), and baseline NRS of >6 (2.4 [1.1-4.8]). CONCLUSIONS: Treatment responses to corticosteroids for anorexia may be predicted by PPS, drowsiness, and baseline symptom intensity. Larger prospective studies are needed to confirm these results.
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Corticoesteroides/uso terapéutico , Anorexia/tratamiento farmacológico , Neoplasias/complicaciones , Cuidados Paliativos/métodos , Corticoesteroides/administración & dosificación , Corticoesteroides/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Several reports have demonstrated the use of whole-slide imaging (WSI) for primary pathological diagnosis, but no such studies have been published from Asia. We retrospectively collected 1070 WSI specimens from 900 biopsies and small surgeries conducted in nine hospitals. Nine pathologists, who participated in this study, trained for the College of American Pathologists guidelines, reviewed the specimens and made diagnoses based on digitized, 20× or 40× optically magnified images with a WSI scanner. After a washout interval of over 2 weeks, the same observers reviewed conventional glass slides and diagnosed them by light microscopy. Discrepancies between microscopy- and WSI-based diagnoses were evaluated at the individual institutes, and discrepant cases were further reviewed by all pathologists. Nine diagnoses (0.9%) showed major discrepancies with significant clinical differences between the WSI- and microscopy-based diagnoses, and 37 (3.5%) minor discrepancies occurred without a clinical difference. Eight out of nine diagnoses with a major discrepancy were considered concordant with the microscopy-based diagnoses. No association was observed between the level of discrepancy and the organ type, collection method, or digitized optical magnification. Our results indicate the availability of WSI-based primary diagnosis of biopsies and small surgeries in routine daily practice.
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Neoplasias Gastrointestinales/diagnóstico , Interpretación de Imagen Asistida por Computador/métodos , Humanos , Japón , Variaciones Dependientes del Observador , Patología Clínica/métodos , Patología Quirúrgica/métodos , Reproducibilidad de los Resultados , Estudios RetrospectivosRESUMEN
Recently, more than ten cases of thrombocytopenia, anasarca, fever, reticulin fibrosis, and organomegaly (TAFRO) syndrome or Castleman-Kojima disease exhibiting such symptoms as thrombocytopenia, anasarca, fever, reticulin fibrosis and organomegaly have been reported in Japan. We have found two cases of TAFRO syndrome and have reviewed another eighteen previously reported cases. Histological findings of the lymph nodes and levels of interleukin 6 (IL-6) and vascular endothelial growth factor in both serum/plasma and effusions are important characteristics for diagnosing this syndrome.
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Enfermedad de Castleman/diagnóstico , Edema/diagnóstico , Fiebre/diagnóstico , Trombocitopenia/diagnóstico , Adulto , Humanos , Interleucina-6/sangre , Japón , Ganglios Linfáticos/patología , Masculino , SíndromeRESUMEN
BACKGROUND: Although the place of death has a great influence on the quality of death and dying for cancer patients, whether the survival time differs according to the place of death is unclear. The primary aim of this study was to explore potential differences in the survival time of cancer patients dying at home or in a hospital. METHODS: This multicenter, prospective cohort study was conducted in Japan from September 2012 through April 2014 and involved 58 specialist palliative care services. RESULTS: Among the 2426 patients recruited, 2069 patients were analyzed for this study: 1582 receiving hospital-based palliative care and 487 receiving home-based palliative care. A total of 1607 patients actually died in a hospital, and 462 patients died at home. The survival of patients who died at home was significantly longer than the survival of patients who died in a hospital in the days' prognosis group (estimated median survival time, 13 days [95% confidence interval (CI), 10.3-15.7 days] vs 9 days [95% CI, 8.0-10.0 days]; P = .006) and in the weeks' prognosis group (36 days [95% CI, 29.9-42.1 days] vs 29 days [95% CI, 26.5-31.5 days]; P = .007) as defined by Prognosis in Palliative Care Study predictor model A. No significant difference was identified in the months' prognosis group. Cox proportional hazards analysis revealed that the place of death had a significant influence on the survival time in both unadjusted (hazard ratio [HR], 0.86; 95% CI, 0.78-0.96; P < .01) and adjusted models (HR, 0.87; 95% CI, 0.77-0.97; P = .01). CONCLUSIONS: In comparison with cancer patients who died in a hospital, cancer patients who died at home had similar or longer survival. Cancer 2016;122:1453-1460. © 2016 American Cancer Society.
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Muerte , Neoplasias , Adulto , Anciano , Estudios de Cohortes , Femenino , Servicios de Atención de Salud a Domicilio/estadística & datos numéricos , Mortalidad Hospitalaria , Humanos , Japón , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Cuidados Paliativos/estadística & datos numéricos , Prioridad del Paciente , Estudios Prospectivos , Distribución por Sexo , Análisis de Supervivencia , Factores de TiempoRESUMEN
BACKGROUND: There is no consensus regarding whether cancer-induced hypercalcemia should be treated up until the patient's death. The primary aim of this study was to clarify physicians' attitude toward treating recurrent hypercalcemia in terminally ill cancer patients and associated factors. METHODS: A nationwide, cross-sectional survey was performed involving 757 physicians of the Japanese Society for Palliative Medicine. Physicians' attitude toward treating hypercalcemia in terminally ill patients was assessed based on the response to the question: do you agree that you provide medical treatment for recurrent hypercalcemia up until a patient's death? As the potential determinants of physicians' attitudes, we examined their characteristics, beliefs about hypercalcemia, and beliefs about a good death. RESULTS: We obtained a total of 380 (50.2%) analyzable responses. A total of 163 physicians (43%) agreed that hypercalcemia should be treated up until the patient's death, while the remaining 217 physicians (57%) disagreed. The independent determinants of the attitude included the following: physicians' specialty, belief that hypercalcemia treatment improves pain, belief that hypercalcemia treatment improves nausea, belief that hypercalcemia treatment improves quality of life, belief that hypercalcemia treatment prolongs life, belief that the effect of hypercalcemia treatment reduces gradually, belief that death with hypercalcemia is less distressing, and the perception that being mentally clear is important for a good death. CONCLUSION: Japanese physicians had different attitudes toward treating hypercalcemia in terminally ill patients. Physicians' beliefs about the efficacy of medical treatment for hypercalcemia markedly influenced their attitudes. Clarifying evidence on the effect of hypercalcemia treatment on patients' symptoms and prognoses is strongly encouraged.
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Actitud del Personal de Salud , Conservadores de la Densidad Ósea/uso terapéutico , Difosfonatos/uso terapéutico , Hipercalcemia/terapia , Enfermo Terminal , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Hipercalcemia/complicaciones , Masculino , Persona de Mediana Edad , Neoplasias/complicaciones , Neoplasias/terapia , Dolor/fisiopatología , Médicos/psicología , Pautas de la Práctica en Medicina , Pronóstico , Calidad de Vida , Recurrencia , Encuestas y CuestionariosRESUMEN
PURPOSE: The Glasgow prognostic score (GPS), which uses C-reactive protein and albumin levels, is a good predictor of prognosis in cancer patients undergoing anti-tumor therapy. The objective of this study was to investigate the correlation between GPS and survival among cancer patients in palliative settings, as findings in such populations have not been well described. METHODS: This was a subanalysis of a multicenter, prospective, cohort study in patients who were adults, diagnosed with advanced cancer, and first referred to palliative care service in Japan. Patients who were not receiving anti-tumor therapy and who had undergone laboratory examinations were eligible. Clinical features were analyzed to investigate prognostic factors. RESULTS: A total of 1160 patients were enrolled (41.6 % female; median age, 72 years). The independent predictors were Eastern Cooperative Oncology Group performance status (ECOG PS) score of 4 (hazard ratio (HR), 1.54), liver metastasis (HR, 1.21), dyspnea (HR, 1.35), edema (HR, 1.25), prognostic performance index (HR, 1.56), neutrophil-lymphocyte ratio (HR, 1.43), and GPS of 2 (HR, 1.36). The sensitivity and specificity for 3-week prognosis of a GPS of 2 were 0.879 and 0.410. Median survival time with GPS of 0, 1, and 2 was 58 days (95 % confidence interval, 48-81), 43 days (37-50), and 21 days (19-24), respectively (log-rank test, p < 0.001). CONCLUSION: The GPS was a good prognostic indicator for cancer patients in palliative settings.
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Albúminas/análisis , Proteína C-Reactiva/metabolismo , Neoplasias/terapia , Cuidados Paliativos , Albúmina Sérica/análisis , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Neoplasias/mortalidad , Pronóstico , Modelos de Riesgos Proporcionales , Estudios ProspectivosRESUMEN
Background: The use of serum soluble interleukin 2 receptor (sIL-2R) for the diagnosis of febrile illnesses has not been examined. In this study, febrile patients were classified according to etiology and disease, and serum sIL-2R levels were evaluated. We determined whether serum sIL-2R is a useful marker for differentiating between malignant lymphoma (ML) and non-ML patients and between patients with ML and Kikuchi disease, which present similar clinical manifestations. Methods: This study was a cross-sectional study and included 344 patients with uncomplicated hemophagocytic syndrome, who had a fever of 38 °C or higher within 1 week of admission to our institution. Patient serum sIL-2R was measured, and the serum sIL-2R values are shown as median and IQR. Results: Serum sIL-2R increased above the upper reference limit in all disease groups with fever. The serum sIL-2R level in ML patients (n = 13) was 4760 (2120-6730) U/mL and significantly higher (p < 0.001) than the level of 998 (640-1625) U/mL in non-ML patients (n = 331). The serum sIL-2R level in ML patients (n = 13) was also significantly higher (p < 0.001) compared with that in patients with Kikuchi disease (n = 20; 705 (538-1091) U/mL). Conclusions: Serum sIL-2R tends to exceed the upper reference limit in patients with febrile illnesses. We conclude that the measurement of serum sIL-2R is useful for differentiating ML from non-ML and ML from Kikuchi disease.
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The role of mitochondria in white adipocytes (WAs) has not been fully explored. A recent study revealed that brown adipocytes contain functionally distinct mitochondrial fractions, cytoplasmic mitochondria, and peridroplet mitochondria. However, it is not known whether such a functional division of mitochondria exists in WA. Herein, we observed that mitochondria could be imaged and mitochondrial DNA and protein detected in pellets obtained from the cytoplasmic layer and oil layer of WAs after centrifugation. The mitochondria in each fraction were designated as cytoplasmic mitochondria (CMw) and peridroplet mitochondria (PDMw) in WAs, respectively. CMw had higher ß-oxidation activity than PDMw, and PDMw was associated with diacylglycerol acyltransferase 2. Therefore, CMw may be involved in ß-oxidation and PDMw in droplet expansion in WAs.
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Adipocitos Blancos , Citoplasma , Mitocondrias , Mitocondrias/metabolismo , Mitocondrias/genética , Animales , Citoplasma/metabolismo , Adipocitos Blancos/metabolismo , Adipocitos Blancos/citología , ADN Mitocondrial/metabolismo , ADN Mitocondrial/genética , Ratones , Oxidación-Reducción , Diacilglicerol O-Acetiltransferasa/metabolismo , Diacilglicerol O-Acetiltransferasa/genética , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genéticaRESUMEN
A case of cytoplasmic anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALCL) initially involving the skin in a 44-year-old Japanese female is reported. The patient had a hemorrhagic erythematous tumor on the right thigh without any systemic symptoms. Pathology showed diffuse infiltration of CD30-positive anaplastic large cells positive for epithelial membrane antigen and cytoplasmic ALK. The right inguinal lymph node showed infiltration of tumor cells in the marginal sinus. Only 2 weeks after radiation therapy, the patient developed multiple subcutaneous nodules and lung involvement. Even after subsequent multichemotherapy sessions, cutaneous recurrence occurred. Literature review of cytoplasmic ALK-positive ALCL initially involving in the skin revealed that skin lesions were mostly seen in the extremities and that half of the cases developed extracutaneous lesions. Radiation and chemotherapy were effective for most cases. Inverse RT-PCR identified a tumor necrosis factor receptor-associated factor (TRAF)1-ALK fusion in our case. Most reported cases with this translocation experienced repeated changes in chemotherapy, suggesting poorer prognosis. Although ALK-positive ALCL generally responds well to chemotherapy, the presence of a TRAF1-ALK fusion may suggest resistance to treatment. Detection of fusion partners of ALK is important for predicting clinical courses and deciding treatment options.
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Linfoma Anaplásico de Células Grandes , Humanos , Femenino , Adulto , Linfoma Anaplásico de Células Grandes/diagnóstico , Linfoma Anaplásico de Células Grandes/genética , Quinasa de Linfoma Anaplásico/genética , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Proteínas Tirosina Quinasas Receptoras/uso terapéutico , Factor 1 Asociado a Receptor de TNF/metabolismo , Ganglios Linfáticos/patologíaRESUMEN
The diagnosis of hereditary skin tumors is difficult for "old" diagnostic tools such as immunohistochemistry. Whole-exome sequencing analysis as a "new" diagnostic tool enables us to make a final diagnosis in spite of unknown hereditary diseases in the past. Hereditary leiomyomatosis and renal cell cancer are autosomal dominant hereditary cancer syndromes characterized by uterine myomas, cutaneous leiomyomas, and aggressive renal cell cancer. The syndrome is associated with pathogenic germline variants in the fumarate hydratase gene. Herein, we demonstrate a pathogenic germline variant of the fumarate hydratase gene in a 60-year-old woman with multiple cutaneous leiomyomas, leading to the diagnosis of hereditary leiomyomatosis and renal cell cancer. Whole-exome sequencing analysis using genomic DNA extracted from peripheral blood leukocytes revealed one germline variant in the FH gene on chromosome 1 (c.290G>A, p.Gly97Asp). She received total hysterectomy due to uterine myoma, which strongly supported the diagnosis. No tumor was detected in her kidney by computed tomography and ultrasound examination. Genetic examination for the mutation of the fumarate hydratase gene is important in order to reach the correct diagnosis and to detect renal cancer at its early stage.
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A 91-year-old dog-owning woman with a history of hypertension and femoral neck fracture consulted our hospital with fever and femur pain with redness. Laboratory test results showed leukocytosis with 85% neutrophils and high values of C-reactive protein and procalcitonin. In addition, growth of Gram-positive streptococcus was observed in two independent blood culture sets. The isolated bacterium was identified as Streptococcus canis on the basis of biochemical properties and sequencing analyses of the 16S rRNA gene. The patient recovered completely without critical illness following prompt antimicrobial treatment with ceftriaxone. S. canis, a ß-hemolytic Lancefield group G streptococcus, is in general isolated from various animal sources, but its isolation from a human clinical sample is extremely rare. Since ß-hemolytic streptococci can cause severe infectious diseases such as necrotizing fasciitis, it is absolutely necessary to start antimicrobial treatment immediately. It is necessary to identify pathogenic bacteria carefully and to obtain information on a patient's background, including history of contact with an animal, when S. canis is isolated.
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Sepsis/diagnóstico , Sepsis/microbiología , Infecciones Estreptocócicas/diagnóstico , Streptococcus/aislamiento & purificación , Zoonosis/diagnóstico , Zoonosis/microbiología , Anciano de 80 o más Años , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Ceftriaxona/farmacología , Ceftriaxona/uso terapéutico , Perros , Femenino , Humanos , Japón , Pruebas de Sensibilidad Microbiana , Mascotas , Infecciones Estreptocócicas/microbiología , Streptococcus/efectos de los fármacosRESUMEN
It has been thought that adipocytes lack proliferative ability and do not revert to precursor cells. However, numerous findings that challenge this notion have also been reported. The idea that adipocytes dedifferentiate to fibroblast-like cells with increasing cell number was reported in 1975. This possibility has been ignored despite knowledge gained in the 1990s regarding adipocyte differentiation. Several studies on proliferation and dedifferentiation of adipocytes have been published, most of which were conducted from the perspective of regenerative medicine. However, the concept of proliferation of adipocytes remains unclear. In this study, we postulate a new population of adipocytes, which consist of small sized cells (less than 20 µm in diameter) expressing adipocyte markers, such as adiponectin and peroxisome proliferator-activated receptor γ (PPARγ), but not possessing large lipid droplets. These cells show marked ability to incorporate 5-bromo-2'-deoxyuridine (BrdU), for which reason we termed them "small proliferative adipocytes (SPA)". In addition, SPA are observed in the stromal vascular fraction. Since SPA are morphologically different from mature adipocytes, we regarded them as committed progenitor cells. When proliferation of adipocytes in vivo is assessed by measuring BrdU incorporation and expression levels of proliferating cell nuclear antigen (PCNA) in isolated fractions of adipocytes from adipose tissues, subcutaneous SPA proliferate less actively than visceral SPA. Treatment with pioglitazone increases the number of proliferating SPA in subcutaneous, but not visceral, fat, suggesting that SPA may be important in regulating systemic insulin sensitivity and glucose metabolism.
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Adipocitos/citología , Adipoquinas/biosíntesis , Proliferación Celular , Células Madre/citología , Adipocitos/metabolismo , Animales , Bromodesoxiuridina , Desdiferenciación Celular , Diferenciación Celular , Células Cultivadas , Humanos , Inmunohistoquímica , PPAR gamma/biosíntesis , Pioglitazona , Antígeno Nuclear de Célula en Proliferación/biosíntesis , TiazolidinedionasRESUMEN
Obesity consists of hypertrophy and hyperplasia of adipocytes. Although the number of adipocytes is influenced by anatomical location, nutritional environment, hormone and genetic variation, it has been thought to be determined by the proliferation of precursor cells and subsequent differentiation. However, our recent research has identified the population of small adipocytes less than 20 µm in diameter, exhibiting tiny or no lipid droplets and expressing adipocyte marker proteins (small proliferative adipocytes: SPA) in isolated adipocytes. Notably, 5-bromo-2'-deoxyuridine (BrdU) incorporation and proliferating cell nuclear antigen (PCNA) expression were detected in these cells. In this study, we investigated the role of SPA in development of adipose tissue using genetically obese diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats and their non-obese and non-diabetic littermates, Long-Evans Tokushima Otsuka (LETO) rats. Proliferation of SPA was determined by measurement of PCNA at the protein level in isolated fractions of adipocytes with collagenase digestion. In general, expression levels of PCNA rose, reached a maximum, and declined in adipose tissues during aging. The expression levels of PCNA were maximum in epididymal fat at 32 w and 12 w of age in LETO and OLETF, respectively. They reached the maximum at 20 w of age both in LETO and OLETF in mesenteric fat. Although the PCNA expression level was higher in OLETF in the early period, it reversed later. Enlargement of adipocytes developed during aging, which was enhanced when the expression levels of PCNA declined. These results suggest that proliferation of SPA may prevent adipocyte hypertrophy and the resultant development of metabolic disorders.
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Adipocitos/citología , Grasa Intraabdominal/metabolismo , Obesidad/patología , Ratas Endogámicas OLETF , Adipocitos/patología , Envejecimiento , Animales , Proliferación Celular , Diabetes Mellitus Tipo 2 , Masculino , Obesidad/etiología , Obesidad/fisiopatología , Antígeno Nuclear de Célula en Proliferación/biosíntesis , RatasRESUMEN
We investigated the effect of Trichinella infection on glucose tolerance and (pro- or anti-inflammatory) macrophage status in adipose tissue. Ob/ob mice and high fat-fed mice (obesity model) and C57/BL mice (control mice) were orally infected with (infected group) or without (uninfected group) 400 Trichinella per mouse. Four weeks later, the mice were subjected to investigation, which showed that fasting plasma glucose levels decreased in the infected group of C57/BL and ob/ob mice. Glucose tolerance, evaluated with intraperitoneal GTT, improved in the infected group of ob/ob mice and high fat-fed mice compared with the uninfected groups. Additional assay included anti-inflammatory macrophage (M2) markers and pro-inflammatory macrophage (M1) markers, with the aim to explore the effect of Trichinella infection on adipose tissue inflammation, since our previous study identified anti-inflammatory substances in secreted proteins by Trichinella. The result showed that mRNA levels of M2 markers, such as CD206, arginase and IL-10, increased, whereas M1 markers, such as CD11c, iNOS and IL-6, decreased in the stromal vascular fraction (SVF) isolated from epididymal fat in ob/ob mice. Residential macrophages obtained from the peritoneal lavage exhibited lower M1 markers and higher M2 markers levels in the infected group than in the uninfected group. Trichinella infection increases the ratio of M2/M1 systemically, which results in an improvement in pro-inflammatory state in adipose tissue and amelioration of glucose tolerance in obese mice.
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Glucemia/metabolismo , Macrófagos/metabolismo , Obesidad/complicaciones , Obesidad/metabolismo , Triquinelosis/complicaciones , Triquinelosis/metabolismo , Adipocitos/metabolismo , Tejido Adiposo/metabolismo , Animales , Macrófagos/patología , Ratones , Ratones Endogámicos C57BL , Ratones ObesosRESUMEN
OBJECTIVES: To elucidate the differences between pleomorphic adenomas and schwannomas occurring in the parapharyngeal space by histogram analyses of apparent diffusion coefficient (ADC) values measured with diffusion-weighted MRI. METHODS: This retrospective study included 29 patients with pleomorphic adenoma and 22 patients with schwannoma arising in the parapharyngeal space or extending into the parapharyngeal space from the parotid region. Using pre-operative MR images, ADC values of tumor lesions showing the maximum diameter were measured. The regions of interest for ADC measurement were placed by contouring the tumor margin, and the histogram metrics of ADC values were compared between pleomorphic adenomas and schwannomas regarding the mean, skewness, and kurtosis by Wilcoxon's rank sum test. Subsequent to the primary analysis which included all lesions, we performed two subgroup analyses regarding b-values and magnetic field strength used for MRI. RESULTS: The mean ADC values did not show significant differences between pleomorphic adenomas and schwannomas for the primary and subgroup analyses. Schwannomas showed higher skewness (p = 0.0001) and lower kurtosis (p = 0.003) of ADC histograms compared with pleomorphic adenomas in the primary analysis. Skewness was significantly higher in schwannomas in all the subgroup analyses. Kurtosis was consistently lower in schwannomas but did not reach statistical significance in one subgroup analysis. CONCLUSIONS: Skewness and kurtosis showed significant differences between pleomorphic adenomas and schwannomas occupying the parapharyngeal space, but the mean ADC values did not. Our results suggest that the skewness and kurtosis of ADC histograms may be useful in differentiating these two parapharyngeal tumors.