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1.
Artículo en Zh | MEDLINE | ID: mdl-36052593

RESUMEN

Hydrogen sulphide poisoning is an acute poisoning event that occurs frequently in summer. A case of acute hydrogen sulphide poisoning in a confined space in August 2018 was investigated and clinical data were analyzed. This is a typical case of acute hydrogen sulfide gas poisoning in a confined space. The main cause of the accident is the lack of occupational protection and illegal rescue. Among the 5 patients, 3 died, 1 patient had long-term sequelae of nervous system damage such as cortical blindness, and 1 patient was cured.


Asunto(s)
Intoxicación por Gas , Sulfuro de Hidrógeno , Intoxicación , Accidentes , Accidentes de Trabajo , Espacios Confinados , Humanos
3.
Acta Virol ; 58(4): 374-9, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25518721

RESUMEN

Swine influenza virus (SIV), one of the most important zoonotic agents, is associated with major public health concerns. The current study was conducted to investigate the role of p38 mitogen-activated protein kinase (p38 MAPK) in the regulation of the inflammatory response to acute lung injury (ALI) induced by SIV of H9N2 subtype (H9N2-SIV) in mice. For this purpose, BALB/c mice were intranasally infected with 20 LD(50) of H9N2-SIV (infected group), while non-infected mice served as control (control group). To assess the effect of p38 MAPK, its specific inhibitor SB203580 was employed followed by SIV infection (SB group). At various times after infection, mouse lungs were subjected to pathological and histological observations and detection of inflammatory cytokines tumor necrosis factor α (TNF)-α, interleukin (IL)-1ß, IL-6, and IL-10 and phosphorylated p38 MAPK. The obtained results showed obvious inflammatory responses, injury and raised levels of inflammatory cytokines and phosphorylated p38 MAPK in the lungs of virus-infected mice. In the mice inoculated with the virus alone, the level of phosphorylated p38 MAPK increased from day 2 and peaked at day 6 post infection (p.i.). However, SB203580 caused lower increases in inflammatory cytokines and phosphorylated p38 MAPK and a milder lung injury. These findings indicate that the activation of p38 MAPK upregulated the inflammatory responses to H9N2-SIV-induced ALI, increased its severity and promoted the production of inflammatory cytokines.


Asunto(s)
Lesión Pulmonar Aguda/inmunología , Subtipo H9N2 del Virus de la Influenza A/fisiología , Proteínas Quinasas p38 Activadas por Mitógenos/inmunología , Lesión Pulmonar Aguda/genética , Lesión Pulmonar Aguda/patología , Animales , Femenino , Humanos , Subtipo H9N2 del Virus de la Influenza A/inmunología , Interleucina-1beta/genética , Interleucina-1beta/inmunología , Interleucina-6/genética , Interleucina-6/inmunología , Pulmón/inmunología , Pulmón/patología , Ratones , Ratones Endogámicos BALB C , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología , Proteínas Quinasas p38 Activadas por Mitógenos/genética
4.
Zhonghua Wei Chang Wai Ke Za Zhi ; 27(2): 158-162, 2024 Feb 25.
Artículo en Zh | MEDLINE | ID: mdl-38413083

RESUMEN

Gastric cancer is a common malignant tumor in China. Most gastric cancer patients are already in the locally advanced stage when they seek medical treatment. Radical surgery is the main treatment for gastric cancer. The quality control of postoperative perioperative management is of great significance in improving the surgical treatment effect and the quality of life of patients. This article systematically summarizes seven aspects, including diet and nutrition management, antimicrobial drug management, pain management, prophylactic anticoagulation management, airway management, postoperative complication management, and discharge and follow-up management, establishes clear quality standards, and achieves the goals of reducing postoperative complications, standardizing perioperative medication use, reducing hospitalization time and costs, thereby reducing patient burden and improving the economic and social benefits of medical institutions.


Asunto(s)
Neoplasias Primarias Secundarias , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirugía , Neoplasias Gástricas/complicaciones , Gastrectomía/efectos adversos , Estudios Retrospectivos , Calidad de Vida , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/etiología , Neoplasias Primarias Secundarias/complicaciones , Neoplasias Primarias Secundarias/cirugía , Control de Calidad
5.
Nanotechnology ; 24(19): 195603, 2013 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-23595114

RESUMEN

Solution-processed zinc oxide (ZnO) thin films are promising candidates for low-temperature-processable active layers in transparent thin film electronics. In this study, control of growth rate anisotropy using ZnO nanoparticle seeds, capping ions, and pH adjustment leads to a low-temperature (90 ° C) hydrothermal process for transparent and high-density ZnO thin films. The common 1D ZnO nanorod array was grown into a 2D continuous polycrystalline film using a short-time pure solution method. Growth rate anisotropy of ZnO crystals and the film morphology were tuned by varying the chloride (Cl(-)) ion concentration and the initial pH of solutions of zinc nitrate and hexamethylenetetramine (HMTA), and the competitive adsorption effects of Cl(-) ions and HMTA ligands on the anisotropic growth behavior of ZnO crystals were proposed. The lateral growth of nanorods constituting the film was promoted by lowering the solution pH to accelerate the hydrolysis of HMTA, thereby allowing the adsorption effects from Cl(-) to dominate. By optimizing the growth conditions, a dense ∼100 nm thickness film was fabricated in 15 min from a solution of [Cl(-)]/[Zn(2+)] = 1.5 and pH=  4.8 ± 0.1. This film shows >80% optical transmittance and a field-effect mobility of 2.730 cm(2) V(-1) s(-1) at zero back-gate bias.

6.
Genet Mol Res ; 12(1): 587-96, 2013 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-23512676

RESUMEN

We analyzed synonymous codon usage patterns of the mitochondrial genomes of 43 parasitic platyhelminth species. The relative synonymous codon usage, the effective number of codons (NC) and the frequency of G+C at the third synonymously variable coding position were calculated. Correspondence analysis was used to determine the major variation trends shaping the codon usage patterns. Among the mitochondrial genomes of 19 trematode species, the GC content of third codon positions varied from 0.151 to 0.592, with a mean of 0.295 ± 0.116. In cestodes, the mean GC content of third codon positions was 0.254 ± 0.044. A comparison of the nucleotide composition at 4-fold synonymous sites revealed that, on average, there was a greater abundance of codons ending on U (51.9%) or A (22.7%) than on C (6.3%) or G (19.14%). Twenty-two codons, including UUU, UUA and UUG, were frequently used. In the NC-plot, most of points were distributed well below or around the expected NC curve. In addition to compositional constraints, the degree of hydrophobicity and the aromatic amino acids also influenced codon usage in the mitochondrial genomes of these 43 parasitic platyhelminth species.


Asunto(s)
Composición de Base/genética , Codón/genética , Genoma Mitocondrial/genética , Platelmintos/genética , Animales , Secuencia de Bases , Variación Genética , Proteínas del Helminto/genética , Proteínas Mitocondriales/genética , Modelos Genéticos , Platelmintos/clasificación , Especificidad de la Especie
7.
Eur Rev Med Pharmacol Sci ; 26(4): 1183-1195, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35253175

RESUMEN

OBJECTIVE: Huperzine A, which was extracted from a Chinese herb, is a reversible and selective inhibitor of acetylcholinesterase (AChE), which is used as an anti-Alzheimer's drug that exerts evident pretreatment effects against exposure to organophosphate chemical warfare agents or pesticides. The aims of this study were to establish an LC-MS/MS method for the detection of HupA in biological samples and to investigate the pharmacokinetics of HupA polylactic-co-glycolic acid nanoparticles (HupA-PLGA-NPs) with different diameters in mice. MATERIALS AND METHODS: The proposed LC-MS/MS method was established by optimizing the MS conditions and validating the specificity, linear range, lower limit, precision, accuracy, matrix effects, absolute recovery, and sample stability of the method. ICR mice were divided into three treatment groups: the HupA control group, the 46.4-nm HupA-PLGA-NP group and the 208.5-nm HupA-PLGA-NP group. All the mice in the three groups were administered 0.5 mg/kg HupA via the tail vein. The pharmacokinetic parameters in plasma and the brain were detected by LC-MS/MS. Pharmacokinetic parameters were analyzed using PKS pharmacokinetic software, and the relative bioavailability and brain-targeted drug targeting efficiency (DTE) were also calculated. RESULTS: The distributions of HupA-PLGA-NP groups showed marked changes compared with that of HupA in mice in vivo, and the particle size of nanodrugs exerted a significant effect on the pharmacokinetic parameters in mice. The half-life (T1/2) values in plasma of the 46.4- and 208.5-nm HupA-PLGA-NPs were 1.53- and 1.96-fold longer than that of the HupA at the same dose. The bioavailabilities of the two nanoparticles were 1.93- and 2.19-fold higher than that of HupA, respectively. In the brain, the Tmax values of the two HupA-PLGA-NPs of different sizes was 1.25 h, which was clearly longer than that of HupA (0.5 h), and the corresponding T1/2 values were 12.53 h and 8.47 h, which were 1.82- and 1.23-fold higher than that of HupA (6.89 h). In addition, the brain targeting index of the 46.40-nm HupA-PLGA-NPs was 1.48, which revealed an evident brain-targeting effect. CONCLUSIONS: The LC-MS/MS method has the advantages of good specificity, high sensitivity and needing a low sample amount and is economical and particularly suitable for determining the drug content in plasma and brain samples. The NP size is associated with the distribution patterns of nanodrugs. Therefore, a particular NP size can be selected to maximize the pharmacodynamics effects and control the toxicity of nanodrugs.


Asunto(s)
Portadores de Fármacos , Nanopartículas , Acetilcolinesterasa/farmacología , Animales , Encéfalo , Cromatografía Liquida , Portadores de Fármacos/química , Glicoles/farmacología , Ratones , Ratones Endogámicos ICR , Nanopartículas/química , Tamaño de la Partícula , Espectrometría de Masas en Tándem
8.
Zhonghua Wei Chang Wai Ke Za Zhi ; 24(10): 883-888, 2021 Oct 25.
Artículo en Zh | MEDLINE | ID: mdl-34674463

RESUMEN

Objective: To establish a novel nomogram to predict overall survival of patients with gastric neuroendocrine neoplasms (g-NEN). Methods: A case control study was conducted. Clinicopathological and follow-up data of patients with g-NEN who were treated in two academic medical centers in Southern China between July 2008 and June 2018 were retrospectively collected, including 174 patients from Sun Yat-sen University Cancer Center and 102 patients from the First Affiliated Hospital of Sun Yat-sen University. Univariate survival analysis using Kaplan-Meier method and multivariate analysis using Cox regression were performed to identify prognostic factors. A nomogram was subsequently established based on prognostic factors. Harrell's concordance index (C-index), receiver operating characteristic (ROC) curve, calibration curve and decision curve analysis (DCA) were used to verify the performance of the model according to differentiation, calibration and clinical utility. Results: A total of 276 patients were enrolled in the study, of whom 189 patients were male and 87 were female. The age at diagnosis was below 60 years old in 150 patients and 60 years or older in 126 patients. There were patients diagnosed with gastric neuroendocrine carcinoma (g-NEC) and 101 patients with gastric neuroendocrine tumor (g-NET). The number of patients with primary tumor locating at upper, middle and lower parts of stomach was 131, 98 and 47, respectively. As for TNM stage, 72 patients were categorized as stage I, 26 patients stage II, 93 patients stage III, and 85 patients stage IV. Univariate analysis indicated that age, pathological type, primary site, Ki-67 index, T stage, N stage, and M stage were associated with overall survival of g-NEN patients (all P<0.05). Multivariate regression analysis testified that high Ki-67 index, advanced T stage and advanced M stage were independent prognostic factors (all P<0.05). The C-index of the nomogram was 0.806 (95%CI: 0.769-0.863). The calibration curve of the nomogram showed that the predicted survival rate was consistent with the actual survival rate in g-NEN patients. The ROC curves and DCA showed that the nomogram had better differentiation and clinical utility than the American Joint Committee on Cancer (AJCC) 8th TNM staging system (the area under the ROC curve was 0.862 vs. 0.792). Conclusion: The first nomogram to predict overall survival of patients with g-NEN is established and verified in this study, which provides individual prediction of 3-year overall survival rate and is applicable to both g-NET and g-NEC patients.


Asunto(s)
Tumores Neuroendocrinos , Nomogramas , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos
9.
Zhonghua Xue Ye Xue Za Zhi ; 41(4): 297-301, 2020 Apr 14.
Artículo en Zh | MEDLINE | ID: mdl-32447933

RESUMEN

Objective: To investigate the clinical characteristics and prognosis in adult acute myeloid leukemia (AML) patients with FLT3-ITD and CEBPA double-mutated (CEBPAdm) co-mutation. Methods: Clinical data and prognostic factors were retrospectively analyzed in adult AML patients with FLT3-ITD and CEBPAdm co-mutation at The First Affiliated Hospital of Zhengzhou University from January 2016 to September 2018. Results: Among 599 non-acute promyelocytic leukemia (APL) patients, 268 received gene mutation detection, who were divided into 4 groups including 19 FLT3-ITD positive (FLT3-ITD(+)) and CEBPAdm positive (CEBPAdm(+)) cases (group A) , 84 FLT3-ITD(+) and CEBPAdm(-) cases (group B) , 95 FLT3-ITD(-) and CEBPAdm(+) cases (group C) , 70 double negative mutation cases (group D) . Gender, platelet count, FAB classification, induction treatment regimen and fusion gene mutation were comparable among four groups (P>0.05) , while age onset, peripheral white blood cell (WBC) count, hemoglobin, percentage of blasts in peripheral blood, percentage of blasts in bone marrow, complete remission rate (CR(1) rate) after the first induction chemotherapy, the relapse rate, the median progression-free survival (PFS) time, and median overall survival (OS) time were significantly different between groups (P<0.05) . When compared in pairs, gender, age onset, hemoglobin, platelet count, FAB classification in group A were not statistically different compared to group B, C and D (P>0.05) , while patients in group A had higher WBC count, blasts in peripheral blood, minimal residual disease (MRD) in bone marrow. The CR(1) rates of group A, B, C, and D were 50.0%、32.4%、59.8%、39.0% respectively (P=0.003) , and the relapse rates were 55.6%, 50.0%, 21.1%, 40.0% (P<0.001) . As to survival, the median OS in each group was 6.25, 3.0, 15.5, 10.5 months respectively (P<0.001) , and the median PFS was 5.0, 4.0, 10.0, 6.7 months (P=0.032) . Conclusion: Adult AML patients with FLT3-ITD and CEBPAdm co-mutation have a higher leukemia load and low CR(1) rate, which translates into poor prognosis with high relapse rate and short survival time.


Asunto(s)
Proteínas Potenciadoras de Unión a CCAAT/genética , Leucemia Mieloide Aguda , Tirosina Quinasa 3 Similar a fms/genética , Adulto , Humanos , Leucemia Mieloide Aguda/genética , Mutación , Pronóstico , Inducción de Remisión , Estudios Retrospectivos
10.
Sci Adv ; 6(20): eaaz8867, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32426501

RESUMEN

Discovering and optimizing commercially viable materials for clean energy applications typically takes more than a decade. Self-driving laboratories that iteratively design, execute, and learn from materials science experiments in a fully autonomous loop present an opportunity to accelerate this research process. We report here a modular robotic platform driven by a model-based optimization algorithm capable of autonomously optimizing the optical and electronic properties of thin-film materials by modifying the film composition and processing conditions. We demonstrate the power of this platform by using it to maximize the hole mobility of organic hole transport materials commonly used in perovskite solar cells and consumer electronics. This demonstration highlights the possibilities of using autonomous laboratories to discover organic and inorganic materials relevant to materials sciences and clean energy technologies.

11.
Anal Chem ; 80(8): 2982-7, 2008 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-18345645

RESUMEN

The aim of this study is to develop new pH sensors that can be used to test and monitor hydrogen ion activity in hydrothermal conditions. A Zr/ZrO2 oxidation electrode is fabricated for in situ pH measurement of high-temperature aqueous solutions. This sensor responds rapidly and precisely to pH over a wide range of temperature and pressure. The Zr/ZrO2 electrode was made by oxidizing zirconium metal wire with Na2CO3 melt, which produced a thin film of ZrO2 on its surface. Thus, an oxidation-reduction electrode was produced. The Zr/ZrO2 electrode has a good electrochemical stability over a wide range of pH in high-temperature aqueous solutions when used with a Ag/AgCl reference electrode. Measurements of the Zr/ZrO2 sensor potential against a Ag/AgCl reference electrode is shown to vary linearly with pH between temperatures 20 and 200 degrees C. The slope of the potential versus pH at high temperature is slightly below the theoretical value indicated by the Nernst equation; such deviation is attributed to the fact that the sensor is not strictly at equilibrium with the solution to be tested in a short period of time. The Zr/ZrO2 sensor can be calibrated over the conditions that exist in the natural deep-seawater. Our studies showed that the Zr/ZrO2 electrode is a suitable pH sensor for the hydrothermal systems at midocean ridge or other geothermal systems with the high-temperature environment. Yttria-stabilized zirconia sensors have also been used to investigate the pH of hydrothermal fluids in hot springs vents at midocean ridge. These sensors, however, are not sensitive below 200 degrees C. Zr/ZrO2 sensors have wider temperature range and can be severed as good alternative sensors for measuring the pH of hydrothermal fluids.

12.
Anal Chem ; 80(22): 8807-13, 2008 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-18855413

RESUMEN

Gold as a hydrogen-sensing electrode for in situ measurement of dissolved H2 in aqueous solutions under extreme conditions is reported. The dissolved H2 sensor, constructed with a Au-based sensing element and coupled with a YSZ/HgO/Hg electrode, is well suited for determining dissolved H2 concentrations of aqueous fluids at elevated temperatures and pressures. The Au electrode is made of Au wire mounted in a quartz bar, which can be pressurized and heated in the high-pressure and -temperature conditions. The Au-YSZ sensor has been tested for its potential response to the concentrations of dissolved H2 in fluids by using a flow-through reactor at high temperatures up to 400 degrees C and pressures to 38 MPa. Good sensitivity and linear response between the hydrogen concentrations in the fluids and the H2 sensor potentials are reported for hydrogen gas in the concentration range of 0.1-0.001 M H2 in aqueous fluids at temperatures up to 340 degrees C and 30 MPa. Nernstian response of the cell potential to dissolved H2 in fluids was determined at 340 degrees C and 30 MPa, described as follows: DeltaE = 0.9444 + 0. 0603 log m H2 The experimental results indicate that the Au-YSZ/HgO/Hg cell can be used to measure the solubility of H2 in aqueous fluid at temperatures and pressures near to the critical state of water. Thus, this type of Au hydrogen sensor could be easily used for in situ measurement of H2 in hydrothermal fluids in a high-pressure vessel, or at midocean ridge, due to its structure of compression resistance.

13.
Eur Rev Med Pharmacol Sci ; 22(9): 2549-2555, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29771405

RESUMEN

OBJECTIVE: To study the correlations of sex determining region Y-box 9 (SOX9) expression with serum type-1 insulin-like growth factor (IGF-1), interleukin-1α (IL-1α), and interleukin-6 (IL-6) in skin lesion tissues of patients with acne. PATIENTS AND METHODS: Six patients with acne who were treated for the first time in our outpatient clinic from June 2017 to July 2017 were selected as observation group, and 6 normal subjects were selected as control group. The expression of SOX9 was detected by immunohistochemistry. The protein expressions of IGF-1, IL-1α, and IL-6 were detected by enzyme-linked immunosorbent assay (ELISA). SOX9 was detected by quantitative polymerase chain reaction (qPCR). RESULTS: Compared with that in control group, the expression of SOX9 in observation group was significantly increased (p < 0.05). Compared with those in control group, the expressions of IGF-1, IL-1α and IL-6 in observation group were significantly increased (p < 0.05). Compared with that in control group, the mRNA expression of SOX9 in observation group was significantly increased (p < 0.05). SOX9 was positively correlated with IGF-1, IL-1α and IL-6. CONCLUSIONS: The expressions of SOX9, IGF-1, IL-1α, and IL-6 in skin lesion tissues of patients with acne are increased, and SOX9 is positively correlated with IGF-1, IL-1α, and IL-6 and can be used as a target for the treatment of acne inflammation.


Asunto(s)
Acné Vulgar/metabolismo , Mediadores de Inflamación/sangre , Factor I del Crecimiento Similar a la Insulina/análisis , Interleucina-1alfa/sangre , Interleucina-6/sangre , Factor de Transcripción SOX9/análisis , Piel/química , Acné Vulgar/sangre , Acné Vulgar/genética , Estudios de Casos y Controles , Humanos , Factor de Transcripción SOX9/genética , Regulación hacia Arriba
14.
Leukemia ; 20(11): 2025-33, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16990779

RESUMEN

Wilms tumor protein 1 (WT1) is a transcription factor overexpressed in several types of leukemia and solid tumors. For this reason, WT1 is an attractive target for immunotherapy. Four peptide nonamers from WT1 have been identified by others to generate a WT1-specific cytotoxic response in the context of human leukocyte antigen (HLA)-A0201 and A2402. However, as WT1 is a self-antigen, breaking tolerance is a potential obstacle to vaccination. Here, we use a strategy to circumvent tolerance by designing synthetic immunogenic analog peptides that could crossreact to the native peptides (a heteroclitic response). A number of synthetic peptides derived from nonamer sequences of the WT1 protein were designed in which single amino-acid substitutions were introduced at HLA-A0201 major histocompatibility complex (MHC)-binding positions. Several of new peptides could stabilize MHC class I A0201 molecules better than native sequences. Some analogs were also able to elicit WT1-specific T-cell recognition and cytotoxic T-cell lymphocytes more effectively than native sequences. Importantly, T cells stimulated with the new analogs crossreacted with the native WT1 peptide sequence and were able to kill HLA-matched chronic myeloid leukemia cell lines. In conclusion, analog heteroclitic WT1 peptides with increased immunogenicity can be synthesized and are potential cancer vaccine candidates.


Asunto(s)
Vacunas contra el Cáncer/inmunología , Antígenos HLA-A/inmunología , Leucemia Mielógena Crónica BCR-ABL Positiva/terapia , Fragmentos de Péptidos/inmunología , Linfocitos T/inmunología , Proteínas WT1/genética , Secuencia de Aminoácidos , Antígenos CD8/inmunología , Línea Celular Tumoral , Epítopos/inmunología , Antígenos HLA-A/metabolismo , Antígeno HLA-A2 , Humanos , Tolerancia Inmunológica/inmunología , Interferón gamma/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/inmunología , Fragmentos de Péptidos/síntesis química , Fragmentos de Péptidos/metabolismo , Unión Proteica/inmunología , Linfocitos T/citología , Linfocitos T/metabolismo , Proteínas WT1/metabolismo
15.
Cancer Epidemiol Biomarkers Prev ; 9(2): 199-205, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10698482

RESUMEN

Occupational exposure to p,p'-dichlorodiphenyltrichloroethane (DDT) has been associated with increased pancreatic cancer risk. We measured organochlorine levels in serum obtained at the study enrollment from 108 pancreatic cancer cases and 82 control subjects aged 32-85 years in the San Francisco Bay Area between 1996 and 1998. Cases were identified using rapid case-ascertainment methods; controls were frequency-matched to cases on age and sex via random digit dial and random sampling of Health Care Financing Administration lists. Serum organochlorine levels were adjusted for lipid content to account for variation in the lipid concentration in serum between subjects. Median concentrations of p,p'-dichlorodiphenyldichloroethylene (DDE, 1290 versus 1030 ng/g lipid; P = 0.05), polychlorinated biphenyls (PCBs; 330 versus 220 ng/g lipid; P<0.001), and transnonachlor (54 versus 28 ng/g lipid; P = 0.03) were significantly greater among cases than controls. A significant dose-response relationship was observed for total PCBs (P for trend <0.001). Subjects in the highest tertile of PCBs (> or =360 ng/g lipid) had an odds ratio (OR) of 4.2 [95% confidence interval (CI) = 1.8-9.4] compared to the lowest tertile. The OR of 2.1 for the highest level of p,p'-DDE (95% CI = 0.9-4.7) diminished (OR = 1.1; 95% CI = 0.4-2.8) when PCBs were included in the model. Because pancreatic cancer is characterized by cachexia, the impact of this on the serum organochlorine levels in cases is difficult to predict. One plausible effect of cachexia is bioconcentration of organochlorines in the diminished lipid pool, which would lead to a bias away from the null. To explore this, a sensitivity analysis was performed assuming a 10-40% bioconcentration of organochlorines in case samples. The OR associated with PCBs remained elevated under conditions of up to 25% bioconcentration.


Asunto(s)
Hidrocarburos Clorados , Insecticidas/efectos adversos , Neoplasias Pancreáticas/etiología , Adulto , Anciano , Anciano de 80 o más Años , Caquexia , Estudios de Casos y Controles , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Insecticidas/sangre , Masculino , Persona de Mediana Edad , Exposición Profesional , Neoplasias Pancreáticas/epidemiología , Neoplasias Pancreáticas/fisiopatología , Factores de Riesgo
16.
Cancer Epidemiol Biomarkers Prev ; 9(11): 1223-32, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11097231

RESUMEN

Pancreatic cancer is a highly fatal cancer with few identified risk factors. Increased risk of pancreatic cancer in tobacco smokers and among diabetic patients is well established, and some reports have suggested associations with coffee consumption and occupational exposure to organochlorines. At present, there is little information regarding the possible association of these risk factors with the known genetic alterations found in pancreatic cancers, such as activation of the K-ras oncogene and inactivation of the p53 tumor suppressor gene. Knowledge of such relationships may help to understand the molecular pathways of pancreatic tumorigenesis. We investigated the association between these molecular defects and risk factors for pancreatic cancer in 61 newly diagnosed patients identified through an ongoing study of pancreatic cancer in the San Francisco Bay Area. Interview information was obtained regarding environmental exposures, medical history, and demographic factors. Serum levels of dichlorodiphenyltrichloroethylene (DDE) and polychlorinated biphenyls were available on a subset of 24 patients. Tumor blocks were located from local hospitals and used for K-ras mutational analysis at codon 12 and for p53 protein immunohistochemistry. The molecular analyses were facilitated through the use of laser capture microdissection, which provides a reliable method to obtain almost pure populations of tumor cells. Mutations in K-ras codon 12 were found in 46 (75%) of 61 pancreatic cancers. A prior diagnosis of diabetes was significantly associated with K-ras negative tumors (P = 0.002, Fisher's exact test). The absence of this mutation was also associated with increased serum levels of DDE, although this association was not statistically significant (P = 0.16, Wilcoxon's test). There was no difference in polychlorinated biphenyl levels between the K-ras wild-type and mutant groups. Immunohistochemical staining for p53 protein did not differ by patient characteristics or clinical history, but significant associations were found with poor glandular differentiation (P = 0.002, chi2 trend test), severe nuclear atypia (P = 0.0007, chi2 trend test), and high tumor grade (P = 0.004, chi2 trend test). Our results are suggestive of the presence of K-ras codon 12 mutation-independent tumorigenesis pathways in patients with prior diabetes and possibly in patients with higher serum levels of DDE. Our results also support a role for the p53 tumor suppressor protein in the maintenance of genomic integrity.


Asunto(s)
Carcinógenos/efectos adversos , Exposición a Riesgos Ambientales , Genes p53/genética , Genes ras/genética , Neoplasias Pancreáticas/genética , Anciano , Estudios de Casos y Controles , Análisis Mutacional de ADN , Complicaciones de la Diabetes , Diclorodifenil Dicloroetileno/efectos adversos , Femenino , Humanos , Inmunohistoquímica , Insecticidas/efectos adversos , Masculino , Anamnesis , Persona de Mediana Edad , Neoplasias Pancreáticas/etiología , Factores de Riesgo
17.
Environ Health Perspect ; 108(2): 147-52, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10656855

RESUMEN

Accidental contamination of the food chain in Michigan in 1973 with polybrominated biphenyls (PBBs) led to the establishment of a registry of exposed individuals in 1976. Serum was collected and analyzed for PBB at the time of enrollment and for targeted studies in the following years. We used the archived PBB data to study the elimination of PBB and to identify factors associated with elimination. A total of 380 women >= 16 years of age who had an initial PBB level of 2 ppb and at least two serum samples drawn when they were not pregnant were included in the analysis. The mean initial PBB level was 20.9 ppb (median 4) and mean time between the first and last measurement was 4.2 years (range 0.5-11.1). PBB was assumed to reach equilibrium in the body before substantial amounts were eliminated and before the first serum measurements were taken; therefore, the entire body was modeled as a single compartment for PBB with exponential decay. Subject-specific decay rate estimates were regressed on predictor variables including initial age, body mass index (BMI), smoking history, breast-feeding duration, and parity. In women with an initial PBB level < 10 ppb, the median half-life was 12.9 years; in those with > 10 ppb, the median half-life was 28.7 years. Decay was significantly slower among women with an initial BMI at or above the median (BMI >= 23). The calculated half-life values are estimates of decay and can be used to estimate body burden of PBB at various points in time other than at the time of serum collection.


Asunto(s)
Contaminantes Ambientales/farmacocinética , Contaminación de Alimentos , Bifenilos Polibrominados/farmacocinética , Adolescente , Adulto , Anciano , Índice de Masa Corporal , Estudios de Cohortes , Contaminantes Ambientales/sangre , Femenino , Semivida , Humanos , Estudios Longitudinales , Michigan , Persona de Mediana Edad , Bifenilos Polibrominados/sangre , Sistema de Registros
18.
Environ Health Perspect ; 109(11): 1133-7, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11712998

RESUMEN

In the early 1970s, the largest industrial accident in the United States resulted in widespread contamination of the food supply in Michigan with polybrominated biphenyls (PBBs). The chemical similarity of PBBs to compounds implicated as endocrine disruptors has raised the question of whether PBBs could affect the reproductive system. In the present analysis we examine the relation between serum measurements of PBBs and the frequency and duration of lactation. Persons who lived on or received food from farms exposed to PBBs were enrolled in a registry by the Michigan Department of Public Health. Female members of the cohort were invited to participate in a telephone survey of reproductive outcomes. The three outcomes of interest in the present analysis were a) the decision to breast-feed (yes/no); b) the duration, in months, of breast-feeding as the main source of nutrition; and c) the total duration, in months, of breast-feeding. None of the three outcomes was significantly associated with serum PBB levels, even after controlling for maternal age, previous history of breast-feeding, body mass index, maternal education, household income, history of smoking in the year before pregnancy, consumption of alcohol during the first trimester of pregnancy, history of thyroid disorder, gestational age of the infant in weeks, time to pregnancy, and year of birth.


Asunto(s)
Accidentes de Trabajo , Contaminantes Ambientales/efectos adversos , Contaminación de Alimentos , Lactancia , Leche Humana/química , Bifenilos Policlorados/efectos adversos , Adolescente , Adulto , Factores de Edad , Índice de Masa Corporal , Niño , Preescolar , Estudios de Cohortes , Toma de Decisiones , Contaminantes Ambientales/análisis , Femenino , Encuestas Epidemiológicas , Humanos , Renta , Lactante , Recién Nacido , Michigan , Paridad , Bifenilos Policlorados/análisis , Embarazo , Factores de Riesgo
19.
Plast Reconstr Surg ; 99(1): 87-91; discussion 92, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8982190

RESUMEN

This article introduces a new surgical method for one-stage reconstruction of the penis. It is applied to the reconstruction of the microphallus as well as to traumatic cases with the residual stump of the amputated penis not less than 3 cm long. By transferring the original glans or the residual penile stump to the anterior portion of the newly reconstructed penile body with microsurgical techniques, we have thus rebuilt a penis with more satisfactory results in both appearance and erotic sensation. Seven patients are reported here who were operated on by this method and who have been followed up for 18 months to 10 years. The good results achieved and the method's advantages over other methods are demonstrated and discussed.


Asunto(s)
Amputación Traumática/cirugía , Pene/cirugía , Colgajos Quirúrgicos/métodos , Adolescente , Adulto , Antebrazo , Humanos , Masculino , Pene/anomalías , Pene/lesiones , Complicaciones Posoperatorias , Colgajos Quirúrgicos/irrigación sanguínea
20.
Pharmazie ; 59(3): 200-2, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15074593

RESUMEN

Considering the narrow therapeutic index of digoxin and the low range between the safe and toxic serum concentrations of this drug, to evaluate the relative bioavailability of tablets and oral solution is necessary. The pharmacokinetic properties of digoxin after oral administration of its hydroxypropyl-beta-cyclodextrin (HPCD) inclusion complex to rabbits and human volunteers were investigated in comparison with those of commercially available tablets. The aqueous solubility of digoxin was enhanced by HPCD for about 2000 times at HPCD concentration of 50% (w/v). But in a human bioavailability study no significant difference was observed in the extent of absorption (AUC(0-t)) and Cmax between the two formulations. Time to reach peak was significantly shorter for the solution than for the tablets (p < 0.01). The pharmacokinetic results from the rabbit study were similar to human studies and no significant difference was observed for AUC, Cmax and Tmax. As the bioavailability of both tablets and solution is equivalent HPCD based oral digoxin solution could serve as an alternative to tablets.


Asunto(s)
Antiarrítmicos/farmacocinética , Ciclodextrinas/farmacología , Digoxina/farmacocinética , beta-Ciclodextrinas , 2-Hidroxipropil-beta-Ciclodextrina , Adolescente , Adulto , Animales , Área Bajo la Curva , Disponibilidad Biológica , Excipientes , Humanos , Masculino , Conejos , Solubilidad , Soluciones , Comprimidos , Equivalencia Terapéutica
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