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1.
J Membr Biol ; 248(6): 1071-8, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26087905

RESUMEN

Arsenic is successfully used in cancer chemotherapy and several cancer treatments on account of its apoptogenic effects. However, it is environmentally hazardous with potential for toxicity when distributed in the soil, water, and food, and long exposure to water contaminated with Arsenic may induce cancers. Some research studies have reported that liver is the storage site and an important target organ for Arsenic toxicity. In the present work, a new kind of organic arsenic compound, 4-(2-nitrobenzaliminyl) phenyl arsenoxide (NPA), was synthesized, and its potential involvement of mitochondria was explored. The results presented that the toxicology of NPA, at least in part, mediated mitochondrial function and may thoroughly destroy mitochondrial membrane physiological functions. NPA induced mitochondrial permeability transition pore (mtPTP) opening that induces mitochondrial biochemical abnormalities as evidenced by mitochondrial swelling, mitochondrial membrane potential breakdown, membrane fluidity alterations, and the strikingly remarkable protection of CsA. Meanwhile, both the decreased respiration rate of state 4 and the increased inner membrane H(+) permeabilization revealed that the inner membrane function regarding important energy production chain was destroyed. The toxicity of NPA is due to its interaction with mitochondrial membrane thiol protein. This conclusion is based on the protective effects of RR, DTT, and MBM(+).


Asunto(s)
Arsenicales/farmacología , Mitocondrias Hepáticas/efectos de los fármacos , Mitocondrias Hepáticas/metabolismo , Animales , Permeabilidad de la Membrana Celular/efectos de los fármacos , Respiración de la Célula , Ciclosporina/farmacología , Hidrógeno/metabolismo , Peroxidación de Lípido , Fluidez de la Membrana/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Proteínas de Transporte de Membrana Mitocondrial , Membranas Mitocondriales/química , Membranas Mitocondriales/metabolismo , Poro de Transición de la Permeabilidad Mitocondrial , Consumo de Oxígeno , Potasio/metabolismo , Ratas
3.
J Thorac Dis ; 16(3): 2070-2081, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38617762

RESUMEN

Background: Electrical impedance tomography (EIT) is a relatively recent functional imaging technique that is both noninvasive and radiation free. EIT measures the associated voltage when a weak current is applied to the surface of the human body to determine the distribution of electrical resistance within tissues. We performed a bibliometrics-based review to explore the geographic hotspots of current research and future trends developing in the field of EIT for mechanical ventilation. Methods: The Web of Science database was searched from its inception to June 25, 2023. CiteSpace software was used to visualize and analyze the relevant literature and identify the most impactful literature, trends, and hotspots. Results: 363 articles describing EIT use in mechanical ventilation were identified. A fluctuating growth in the number of publications was observed from 1998 to 2023. Germany had the highest number of articles (n=154), followed by Italy (n=53) and China (n=52). A cluster analysis of keyword co-occurrence revealed that "titration", "ventilator-related lung injury", and "oxygenation" were the most actively researched terms associated with the use of EIT in mechanically ventilated patients. Conclusions: Significant progress has been made in EIT research for mechanical ventilation. EIT research is limited to a small number of countries with a present research focus on the prevention and treatment of ventilator-related lung injury, oxygenation status, and prone ventilation. These topics are expected to remain research hotspots in the future.

4.
Front Pediatr ; 11: 1169064, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37360361

RESUMEN

Immune thrombocytopenia (ITP) is one of the most prevalent acquired bleeding disorders in children, which is primarily characterized by a decrease in platelet count. It can be classified into two subtypes: primary ITP and secondary ITP. The underlying mechanisms causing ITP are complex and not fully comprehended. Helicobacter pylori (H. pylori) infections can lead to ITP and potentially trigger various autoimmune diseases. Furthermore, there is evidence of a correlation between thyroid disease and ITP. In this case report, we describe the case of an 11-year-old patient who presented with ITP, Hashimoto's thyroiditis (HT), and H. pylori infection. Following anti-H. pylori treatment and thyroxine supplementation, the child's platelet count increased compared to the previous count. The limitation of this report is that the platelet count of this child returned to normal after anti-H. pylori and thyroxine supplementation, so we cannot distinguish the effect of anti-H. pylori and thyroxine supplementation on the platelet count in this child. Despite this limitation, we still believe that early screening for thyroid function and H. pylori, as well as prompt eradication of H. pylori, along with thyroxine supplementation, may be beneficial in treating and improving the prognosis of children diagnosed with ITP.

5.
Sci Rep ; 12(1): 3471, 2022 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-35236868

RESUMEN

Both intra-pore hydrate morphology and inter-pore hydrate distribution influence the physical properties of hydrate-bearing sediments, yet there has been no pore-scale observations of hydrate habit under pressure in preserved pressure core samples so far. We present for the first time a pore-scale micro-CT study of natural hydrate-bearing cores that were acquired from Green Canyon Block 955 in UT-GOM2-1 Expedition and preserved within hydrate pressure-temperature stability conditions throughout sub-sampling and imaging processes. Measured hydrate saturation in the sub-samples, taken from units expected to have in-situ saturation of 80% or more, ranges from 3 ± 1% to 56 ± 11% as interpreted from micro-CT images. Pore-scale observations of gas hydrate in the sub-samples suggest that hydrate in silty sediments at the Gulf of Mexico is pore-invasive rather than particle displacive, and hydrate particles in these natural water-saturated samples are pore-filling with no evidence of grain-coating. Hydrate can form a connected 3D network and provide mechanical support for the sediments even without cementation. The technical breakthrough to directly visualize particle-level hydrate pore habits in natural sediments reported here sheds light on future investigations of pressure- and temperature-sensitive processes including hydrate-bearing sediments, dissolved gases, and other biochemical processes in the deep-sea environment.


Asunto(s)
Sedimentos Geológicos , Metano , Gases/química , Sedimentos Geológicos/química , Metano/química , Temperatura , Microtomografía por Rayos X
6.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 40(1): 20-3, 76, 2009 Jan.
Artículo en Zh | MEDLINE | ID: mdl-19292036

RESUMEN

OBJECTIVE: To study the expression of TFR2 mRNA in mononuclear cells of bone marrow and peripheral blood from children with acute lymphoblastic leukemia, and to explore possible correlations between TFR2 expression and a panel of prognostic/risk factors. METHODS: Bone marrow or peripheral mononuclear cells were isolated from 56 children with newly diagnosed acute lymphoblastic leukemia (ALL) and 15 normal children as control. TFR2 mRNA expression level in mononuclear cell was determined by real-time fluorescence quantitative RT-PCR. RESULTS: Relative expression level of TFR2 mRNA in prednisone good responders (median: 0.0848) was significantly higher than that in prednisone poor responders (median: 0.0126) (P = 0.038). The medians of TFR2 mRNA expression levels in low-risk, moderate-risk and high-risk ALL were 0.1677, 0.0728 and 0.0125 respectively (P = 0.003). The medians of TFR2 mRNA expression levels in three ALL groups with initial WBC counts less than 50 x 10(9)/L, from 50 x 10(9)/L to 100 x 10(9)/L and more than 100 x 10(9)/L were 0.0974, 0.0294 and 0.0078 (P = 0. 013). In addition, the relative TFR2 mRNA level in B-lineage ALL was significantly higher than that in T-ALL, with medians of 0.0636 and 0.0065 respectively (P = 0.004). Ranked correlation analysis revealed that TFR2 expression was negatively correlated to initial white blood cell count, percentage of blast cells and absolute numbers of blasts in peripheral blood, with ranked correlation coefficients of -0.398, -0.307 and 0.421 respectively (correponding P values were 0.003, 0.022 and 0.001). CONCLUSION: TFR2 might be a novel prognostic factor for ALL.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Leucocitos Mononucleares/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangre , Receptores de Transferrina/metabolismo , Adolescente , Biomarcadores de Tumor/genética , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Pronóstico , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Transferrina/genética
7.
BMJ Open ; 8(9): e020735, 2018 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-30232102

RESUMEN

OBJECTIVE: To investigate the association between bronchopulmonary dysplasia (BPD) and the risk of cerebral palsy (CP) in children. DATA SOURCES: We used EMBASE, PubMed and Web of Science to conduct a meta-analysis of studies published before 1 September 2017, written in English whose titles or abstracts discussed an association between BPD and CP. STUDY SELECTION: Observational studies, for example, case-control and cohort studies were included. DATA EXTRACTION AND SYNTHESIS: All review stages were conducted by two reviewers independently. Data synthesis was undertaken via meta-analysis of available evidence. MAIN OUTCOMES AND MEASURES: The prevalence of developing CP was measured after exposure to BPD. RESULTS: Among 1234 initially identified studies, we selected those that addressed an association between BPD and CP according to our preselected inclusion criteria. Our meta-analysis included 11 studies. According to a random effect model, BPD was significantly associated with CP (ORs 2.10; 95% CI 1.57 to 2.82) in preterm infants. Factors explaining differences in the study results included study design, the definition of BPD, the time of diagnosis of CP and whether the studies adjusted for potential confounders. CONCLUSION: This study suggests that BPD is a risk factor for CP. Further studies are required to confirm these results and to detect the influence of variables across studies.


Asunto(s)
Displasia Broncopulmonar/epidemiología , Parálisis Cerebral/epidemiología , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Prevalencia , Factores de Riesgo
8.
Medicine (Baltimore) ; 97(35): e12179, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30170465

RESUMEN

BACKGROUND: Vitamin D deficiency (VDD) has been implicated in the pathogenesis of tuberculosis (TB), but most studies have not reported a significant association. We conducted a meta-analysis to explore the association between vitamin D status and TB in children. METHODS: Web of Science, Ovid Medline, and EMBASE were searched for studies in English that discussed vitamin D status and TB in children before January 22, 2018. RESULTS: From the 585 initially identified studies, we selected those that addressed an association between vitamin D status and TB according to our preselected inclusion criteria. Our meta-analysis included 10 studies. According to the random effects model, TB was significantly associated with VDD (ORs, 1.70; 95% CI, 1.20-2.42; P < .05) in children. Vitamin D levels were significantly lower in TB patients than in controls, with a mean difference d = -5.49 nmol/L (95% CI, -10.42 to -0.55; P < .05), indicating that VDD was significantly associated with TB (OR, 1.78; 95% CI, 1.30-2.44; P < .05) in children. CONCLUSION: This study suggests that vitamin D levels are significantly lower in children with TB/latent TB infection than in controls. TB may contribute to VDD in children. Therefore, VDD may be associated with TB in children.


Asunto(s)
Tuberculosis Latente/sangre , Tuberculosis Pulmonar/sangre , Deficiencia de Vitamina D/microbiología , Vitamina D/sangre , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Tuberculosis Latente/complicaciones , Masculino , Estado Nutricional , Tuberculosis Pulmonar/complicaciones , Deficiencia de Vitamina D/sangre
9.
Rev Neurosci ; 29(2): 151-160, 2018 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-29120862

RESUMEN

White matter injury (WMI) often results in cognitive impairment, behavioral disorders, and cerebral palsy and thus imposes a tremendous burden on society. The cells in brain white matter mainly comprise oligodendrocytes (OLs), astrocytes, and microglia. The dysregulation of OLs development is the pathological hallmark of WMI. Recent studies have demonstrated that microRNAs (miRNAs or miRs) participate in the regulation of OLs development, and the dysregulation of this process represents the pathogenesis of WMI. This review summarizes the progress made in this field that will help clinicians and researchers understand the molecular etiology of WMI and develop miRNAs as new agents for the prevention and treatment of WMI.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , MicroARNs/genética , Oligodendroglía/citología , Sustancia Blanca/citología , Sustancia Blanca/lesiones , Animales , Lesiones Encefálicas/terapia , Humanos , Vaina de Mielina/metabolismo
10.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 24(5): 560-3, 2007 Oct.
Artículo en Zh | MEDLINE | ID: mdl-17922427

RESUMEN

OBJECTIVE: To determine the incidence of TEL-AML1 fusion gene in childhood acute lymphoblastic leukemia (ALL) and to compare the clinical features between TEL-AML1 positive and negative patients. METHODS: Samples of bone marrow or peripheral blood were collected from 95 newly diagnosed ALL children and the TEL-AML1 fusion gene was detected using nested reverse transcription-polymerase chain reaction (RT-PCR). The ALL patients were stratified into TEL-AML1 positive and negative groups and the clinical features were compared. RESULTS: Among 95 patients, 20 (21.05%) were TEL-AML1 positive. The median age of TEL-AML1 positive patients was 5.9 years old and M/F ratio was 1.22:1. There were significant differences between TEL-AML1 positive and negative patients in hepatomegaly (2.75 cm vs. 4 cm below costal arch, P=0.006), splenomegaly (0 cm vs. 3 cm below costal arch, P < 0.001), initial white blood cell count (median 7.40 x 10(9)/L vs.18.70 x 10(9)/L, P=0.011), initial peripheral blood blast (median 2.45 x 10(9)/L vs.11.66 x 10(9)/L, P=0.013), hemoglobin level [(61.45 +/- 13.46) g/L vs. (75.89 +/- 23.11) g/L, P=0.003] and serum lactate dehydrogenase [(621.47 +/- 335.85) U/L vs.(1566.64 +/- 1720.45) U/L, P=0.020], while no differences were found between two groups in age, gender ratio, initial platelet count, percentage of blast in bone marrow, immunophenotypes and the expression of myeloid antigen CD13, CD33 and CD34. The prednisone sensitivity test showed that all 12 TEL-AML1 positive patients were good responders, while there were 11 prednisone poor responders among 40 negative patients (27.50%, P < 0.05). Bone marrow examination on day 15 showed no difference in the rate of complete remission between TEL-AML1 positive and negative patients. CONCLUSION: The incidence of TEL-AML1 fusion gene in cases of ALL is 21.05%. The load of leukemia cells in TEL-AML1 positive patients is significantly smaller than its counterparts, and the blast cells in TEL-AML1 positive patients are more sensitive to prednisone, indicating childhood ALL with TEL-AML1 fusion gene has a favorable prognosis.


Asunto(s)
Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Fusión Génica , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Proteínas Proto-Oncogénicas c-ets/genética , Proteínas Represoras/genética , Adolescente , Médula Ósea/patología , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Fenotipo , Recuento de Plaquetas , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangre , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Prednisona/uso terapéutico , ARN/aislamiento & purificación , Proteína ETS de Variante de Translocación 6
11.
Biol Trace Elem Res ; 114(1-3): 301-11, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17206011

RESUMEN

The interaction between 4,4'-diselenadibenzoic acid and human serum albumin (HSA) was investigated by fluorescence and absorption spectroscopy. The quenching mechanism of fluorescence of HSA by 4,4'-diselenadibenzoic acid was discussed. It is proved that the fluorescence quenching of HSA by 4,4'-diselenadibenzoic acid is a result of the formation of the HSA-4,4'-diselenadibenzoic acid complex. The binding sites number n, apparent corporation constant K, and corresponding thermodynamic parameters, deltaH(theta), deltaG(theta), and deltaS(theta) were calculated. Results indicate that the electrostatic interactions forces played major role in the reaction.


Asunto(s)
Compuestos de Organoselenio/química , Albúmina Sérica/química , Espectrometría de Fluorescencia/métodos , Humanos , Termodinámica
12.
J Matern Fetal Neonatal Med ; 28(11): 1308-1317, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25231370

RESUMEN

OBJECTIVE: We conducted a meta-analysis to evaluate whether maternal hepatitis B virus (HBV) carrier status increases the risk of neonatal complications. METHODS: Publications addressing the association between maternal HBV carrier status and neonatal outcomes were selected from the PubMed, EMBASE, Web of Science, Cochrane Library and China National Knowledge Infrastructure. Publication bias and heterogeneity across studies were evaluated and summary odds ratios, weighted mean difference or standardized mean difference and 95% confidence intervals were calculated and compared between groups. RESULTS: Eighteen studies and 7600 pregnant HBV carriers were selected for analyses. A statistically association with maternal HBV carrier status was demonstrated for premature birth and asphyxia, with no difference found among perinatal mortality, gestational age, small for gestational age, large for gestational age, birth weight, low birth weight, macrosomia, Apgar sore at 1 min, jaundice and congenital anomaly. Heterogeneity across studies was found, and no publication bias was detected. CONCLUSION: Our analysis suggests that maternal hepatitis B carrier status is significantly associated with premature birth and asphyxia. Large-scale prospective studies are still warranted.

13.
Colloids Surf B Biointerfaces ; 130: 207-14, 2015 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-25910636

RESUMEN

The pH-dependent photoluminescence (PL) behavior of carbon nanodots (C-dots) and its mechanism has been exhaustively studied in this work. The PL and UV-vis absorption spectra are reversible in the pH between 3 and 13. We speculate that two kinds of reactions (fast and slow) occurring at the surface of C-dots may contribute to this pH-dependent PL behavior. When C-dots solutions are switched to acidic conditions, they will quickly self-assembled aggregate into larger particles and surface oxygen-related groups of C-dots would be slowly oxidized at room temperature. Moreover, it should be noted that this is the first direct observation of self-assembled aggregation of C-dots under acidic conditions. In addition, the optimal PL spectra of C-dots blue-shift while their sizes increase, so-called 'inverse PL shift' phenomenon is also observed. Meanwhile, as the solution is adjusted to alkaline conditions, a structural tautomerization of C-dots rapidly takes place and hydrogenation/deoxygenation reaction proceeds in a much slower rate. Furthermore, through distinct decay dynamics as well as the characterizations of C-dots at different pHs, the PL properties are proposed to be mainly related to the surface states of C-dots.


Asunto(s)
Carbono/química , Luminiscencia , Nanoestructuras/química , Puntos Cuánticos/química , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Transmisión , Nanoestructuras/ultraestructura , Espectroscopía de Fotoelectrones , Espectrofotometría , Espectroscopía Infrarroja por Transformada de Fourier
14.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 19(2): 439-43, 2011 Apr.
Artículo en Zh | MEDLINE | ID: mdl-21518504

RESUMEN

The aim of this study was to investigate the expression of transferrin receptor 2 (TfR2) mRNA in bone marrow mononuclear cells (BMMNC) of children with hyperplastic anemia (HA), to analyze the correlation of TfR2 mRNA expression level with Hb level, bone marrow erythroid hyperplasia, iron status in body and underlying diseases, and to evaluate the role of TfR2 in erythroid hemopoiesis and the useful value in diagnosis of HA. The experiment was divided into 2 groups: test group, in which 40 patients with HA were enrolled, and control group in which 10 patients without erythroid disorders and hematological malignancies confirmed by bone marrow examination were enrolled. The bone marrow samples of patients in mentioned above 2 groups were collected, the TfR2 mRNA expression in BMMNC of patients with HA was detected by fluorescence-quantitative PCR, the correlation of HA with bone marrow erythroid hyperplasia, iron status of body and underlying diseases was analyzed. The results showed that the relative level of TfR2 mRNA expression in HA patients was significantly higher than that in control patients. The TfR2 mRNA expression level negatively correlated with Hb level in peripheral blood (r = -0.715), while it positively correlated with ratio of bone marrow erythroblasts (r = 0.533). It is concluded that TfR2 mRNA expression in HA patients increases and closely correlates with hyperplasia status of bone marrow and anemia level in peripheral blood.


Asunto(s)
Anemia/metabolismo , Células de la Médula Ósea/metabolismo , Receptores de Transferrina/metabolismo , Adolescente , Anemia/patología , Estudios de Casos y Controles , Niño , Preescolar , Células Precursoras Eritroides/metabolismo , Femenino , Humanos , Lactante , Masculino , ARN Mensajero/metabolismo
15.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 15(2): 272-7, 2007 Apr.
Artículo en Zh | MEDLINE | ID: mdl-17493330

RESUMEN

Mitochondrial ferritin (MtF), a new player in iron metabolism, first identified in 2001, is highly homologous to ferritin both structurally and functionally. Preliminary studies have suggested that MtF might play very important roles in the regulation of mitochondrial iron homeostasis. Leukemic cells, just like other malignant cells, demand more iron for their greater proliferation potential. However, little is known about what roles MtF might play in leukemic cell iron metabolism and cell proliferation. The aim of this study was to investigate the expression of MtF, transferrin receptor 1 (TfR1) and ferritin (Fn) mRNAs in K562 leukemic cells during TPA-induced cell differentiation and to explore the interrelationship between the expression levels of these iron metabolism-related molecules. K562 cells cultured with or without TPA (16 nmol/L) were collected at 24, 72 and 120 hours respectively. Cell differentiation toward monocyte lineage was confirmed by microscopic study (Wright's staining) and flow cytometry. Semiquantitative RT-PCR was performed to determine mRNA expression, with house-keeping gene beta-actin as control reference. This study revealed that over 95% of K562 cells showed morphological features of monocyte/macrophage, and the expression of CD64 on cell surface increased significantly at day 5 with TPA treatment. K562 cells could express a certain level of MtF before TPA-induced differentiation. With increase of TPA-induced cell differentiation, MtF mRNA expressions were downregulated progressively. After 5 days of induced cell differentiation, expression levels of MtF and TfR1 mRNA were just 50.3% and 68.2% of that before TPA treatment. While Fn mRNA expression increased to 1.97 folds of that before TPA treatment. It is concluded that MtF expression is downregulated during TPA-induced K562 cell differentiation, with concomitant downregulation of TfR1 and upregulation of Fn. The coordinated expression regulation of these key iron metabolism-related molecules during cell differentiation may in turn inhibit TfR1-mediated iron uptake via endocytosis and thus adversely affect cell proliferation potential.


Asunto(s)
Transformación Celular Neoplásica/efectos de los fármacos , Ferritinas/biosíntesis , Mitocondrias/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Antígenos CD/metabolismo , Proliferación Celular , Ferritinas/genética , Humanos , Proteínas Reguladoras del Hierro/metabolismo , Células K562 , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Receptores de Transferrina/metabolismo
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