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Objective: To explore the non-bacterial pathogen distribution, epidemiological characteristics, and clinical features of acute respiratory infections in children in Sichuan Province. Methods: Using a retrospective cohort study method, this study selected hospitalized children diagnosed with acute respiratory infections at West China Second Hospital of Sichuan University from February 2019 to January 2021, and tested 13 pathogens using polymerase chain reaction (PCR)-fragment analysis. The children were divided into infant group (<1 year old), toddler group (1 year old ≤ age <3 years old), preschool group (3 years old ≤ age <6 years old) and school-age group (6 years old ≤ age <18 years old). The distribution of pathogen positive rates, seasonal epidemic characteristics, clinical characteristics, and some laboratory test indicators were analyzed in children. Statistical analysis was performed on the results using SPSS 22.0 software, with count data expressed as percentages and inter group comparisons using SPSS 22.0 software χ2 Inspection. Results: A total of 2 922 pediatric patients were included in this study, with 1 748 (59.8%) positive for pathogens detected. Among them, 1 391 (79.6%) were detected as a single pathogen, and 357 (20.4%) were detected as a mixture of two or more pathogens. The most commonly detected pathogens were rhinovirus (HRV) (39.7%), syncytial virus (RSV) (22.8%), and parainfluenza virus (PIV) (12.5%). Pathogen positivity is more common in children under 6 years old (χ2=146.59, P<0.001), with a slightly higher positivity rate in male children (61.3%, 1 047/1 707) than in female children (57.7%, 701/1 215) (χ2=3.91, P=0.048), and compared with pathogen negative children, positive children are more prone to symptoms such as cough, wheezing, and shortness of breath (χ2=259.15, 366.06, 12.48, P<0.001). The distribution of different pathogens varies among children of different age groups, and HRV is more common in children aged 1-3 and 3-6 years old (χ2=9.74, P<0.001), while RSV is more common in children under 1 year old (χ2=178.63, P<0.001), while mycoplasma pneumoniae (MP) and influenza virus (InfA/B) are less common in children under 1 year old (χ2=92.54, 12.90,22.21, P<0.01). The prevalence of multiple pathogens showed seasonal changes. HRV showed a high prevalence trend in spring and autumn, while the prevalence of RSV infection was mainly seen in autumn and winter festivals. The positive rate of different pathogens after the outbreak of novel coronavirus pneumonia was significantly lower than that before the outbreak (χ2=252.68, P<0.001). Conclusion: The detection rate of non-bacterial respiratory pathogens in children in Sichuan Province from 2019 to 2021 is high, which is prone to symptoms such as cough, wheezing, and shortness of breath, with HRV and RSV being the main types. The positive rate of respiratory pathogens varies among different age groups, genders, and seasons.
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Ruidos Respiratorios , Infecciones del Sistema Respiratorio , Lactante , Preescolar , Niño , Humanos , Masculino , Femenino , Adolescente , Adulto Joven , Adulto , Estudios Retrospectivos , Infecciones del Sistema Respiratorio/epidemiología , China/epidemiología , Disnea , Hospitales , Tos , Estaciones del AñoRESUMEN
Objective: To establish a method for detection of 6 BTEXs in urine by Purge and Trap-Gas Chromatography-Mass Spectrometry. Methods: The urine sample need not be diluted, but directly purge and trap in the bottle, separated by gas chromatography column, then simultaneously analyzed by retention time locking (RTL) method and selective ion scanning mode (SIM) . Results: The linear range of 6 BTEXs in urine was good, the correlation coefficient was between 0.997 4 and 0.998 9. The minimum quantification limits was 0.010-0.036 µg/L. The precision was 1.9%-4.7%, and the recovery was 93.1%-101.9%. Conclusion: The method has the advantages of wide linear range, high sensitivity and recovery. It is suitable for the determination of 6 BTEXs in urine of low level occupational-exposed or non-exposed population.
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Exposición Profesional , Cromatografía de Gases y Espectrometría de Masas/métodosRESUMEN
Objective: To establish a purge and trap-gas chromatography-mass spectrometry method based on soil analysis model for the determination of six benzene homologues (benzene, toluene, ethylbenzene, m-xylene, p-xylene and o-xylene) in human blood. Methods: From September 2020 to May 2021, diatomite was used as a dispersant to add 2.0 ml blood sample and fully mixed. The sample was directly injected into the purging and collecting bottle after purging. The gas chromatography column was used for separation. The retention time locking was used for qualitative analysis and the selected ion scanning mode (SIM) was used for detection. The detection limit and recovery rate of the method were analyzed. Results: The linear range of the method for the determination of six benzene homologues in human blood was 0.02-10.00 ng/ml, the correlation coefficient was 0.9927-0.9968, the detection limit was 0.006-0.016 ng/ml, the recovery rate of sample spiking was 84.39%-102.41%, and the precision of the method was 3.06%-6.90%. Conclusion: Purge and trap-gas chromatography-mass spectrometry can simultaneously determine the contents of six benzene homologues in human blood. The pretreatment method is simple, time-saving, and the method has low detection limit, which provides a scientific basis for the detection of benzene homologues in human body.
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Benceno , Xilenos , Humanos , Benceno/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Xilenos/análisis , Derivados del Benceno/análisis , Tolueno/análisisRESUMEN
Fraud in milk and dairy products occurs when cow milk is added to sheep and goat milk for economic reasons. No reliable, selective, and sensitive method exists for quantifying the milk percentage of different species. This work reports the development and validation of a proteomics-based method for the qualitative detection and quantitative determination of cow, sheep, and goat milks in the raw materials used for dairy products. ß-Lactoglobulin was selected as the protein marker because it is a major protein in milk and whey powder. The tryptic peptides LSFNPTQLEEQCHI and LAFNPTQLEGQCHV were used as signature peptides for cow milk and for sheep and goat milks, respectively. The winged peptides LKALPMHIRLSFNPTQL*EEQCHI* and LKALPMHIRLAFNPTQL*EGQCHV* were designed and synthesized as internal standards. Validation of the method showed that it has good sensitivity, specificity, reproducibility, precision, and accuracy. This method is easily applicable in routine laboratory analysis without intensive proteomics background.
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Leche/química , Proteómica , Animales , Bovinos , Femenino , Cabras , Reproducibilidad de los Resultados , OvinosRESUMEN
OBJECTIVE: To compare the clinical efficacy of laparoscopic wedge resection and open wedge resection in the treatment of gastrointestinal stromal tumor. METHODS: Fifty-five patients with gastrointestinal stromal tumor who underwent laparoscopic wedge resection and 61 cases underwent open wedge resection in Tongji Hospital from January 2009 to December 2014 were included into this study. The perioperative, surgical operative and postoperative data of the patients were documented and analyzed. RESULTS: The operation time of laparoscopic group was significantly shorter than that of the open group [(108.2±27.2) min versus (139.9±75.3) min,P=0.021], the amount of intraoperative blood loss was overtly reduced in the laparoscopic group [(57.1±48.7) ml versus (100.6±45.8) ml,P=0.011], the time to postoperative exhaust or defecation was (2.2±1.4) d in the laparoscopic group and (3.5±1.8) d in the open group (P=0.028), and the length of hospital stay was (5.7±1.3) d versus (6.9±2.1) d (P=0.044). There were intraoperative complication in one case and postoperative complications in 5 cases, while neither tumor rupture nor obvious perioperative complication was observed in the laparoscopic group. During the period of follow-up (mean, 15.3 months), only one case of replase occurred in the laparoscopic group while four cases of relapse were observed in the open group. CONCLUSIONS: With experienced skills and to strictly comply with the surgical indications, laparoscopic wedge resection is prior to tranditional open wedge resection for the treatment of gastrointestinal stromal tumor. The laparoscopic wedge resection can achieve the standard of R0 resection, keep the resected tumor with an intact capsule, reduce the operating time and operative trauma, promote the postoperative recovery and get a better prognosis. Therefore, it is a feasible, safe, minimally invasive surgical procedure associated with a rapid postoperative recovery.
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Neoplasias Gastrointestinales/cirugía , Tumores del Estroma Gastrointestinal/cirugía , Laparoscopía/métodos , Pérdida de Sangre Quirúrgica/prevención & control , Defecación , Humanos , Laparoscopía/estadística & datos numéricos , Tiempo de Internación , Recurrencia Local de Neoplasia , Tempo Operativo , Complicaciones Posoperatorias , Pronóstico , Resultado del TratamientoRESUMEN
Purpose: Exposomes are critical drivers of carcinogenesis. However, how they modulate tumor behavior remains unclear. Extensive clinical data link cigarette smoke as a key exposome that promotes aggressive tumors, higher rates of metastasis, reduced response to chemoradiotherapy, and suppressed anti-tumor immunity. We sought to determine whether smoke itself can modulate aggressive tumor behavior in head and neck squamous cell carcinoma (HNSCC) through reprogramming the cellular reductive state. Experimental design: Using established human and murine HNSCC cell lines and syngeneic mouse models, we utilized conventional western blotting, steady state and flux metabolomics, RNA sequencing, quantitative proteomics and flow cytometry to analyze the impact of smoke exposure on HNSCC tumor biology. Results: Cigarette smoke persistently activated Nrf2 target genes essential for maintenance of the cellular reductive state and survival under conditions of increased oxidative stress in HNSCC regardless of HPV status. In contrast to e-cigarette vapor, conventional cigarette smoke mobilizes cellular metabolism toward oxidative stress adaptation, resulting in development of cross-resistance to cisplatin. In parallel, smoke exposure modulates both expression of PDL1 and the secretory phenotype of HNSCC cells through activation of NF-κB resulting in an altered tumor immune microenvironment (TIME) in syngeneic mouse models and altered PBMC differentiation that includes downregulated expression of antigen presentation and costimulatory genes in myeloid cells. Conclusion: Cigarette smoke exposome is a potent activator of the Nrf2 pathway and is a likely primary trigger for the tripartite phenotype of aggressive HNSCC consisting of: 1) reduced chemotherapy sensitivity, 2) enhanced metastatic potential and 3) suppressed anti-tumor immunity. Statement of significance: The smoke exposome drives aggressive tumor behavior, treatment resistance and suppressed immunity through coordinated metabolic reprogramming. Successfully targeting this adaptation is critical to improving survival in smokers with head and neck cancer.
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Pitaya (Hylocereus undatus and H. polyrhizus Britt. & Rose), a perennial succulent plant grown in the tropics, is becoming an emerging and important fruit plant in Taiwan. In September of 2009 and 2010, a number of pitaya plants were found to have a distinctive canker on stems. The disease expanded quickly to most commercial planting areas in Taiwan (e.g., Pintung, Chiayi, and Chunghua). Symptoms on the stem were small, circular, sunken, orange spots that developed into cankers. Pycnidia were erumpent from the surface of the cankers and the stems subsequently rotted. After surface disinfestation with 0.1% sodium hypochloride, tissues adjacent to cankers were placed on acidified potato dextrose agar (PDA) and incubated at room temperature for 1 week, after which colonies with dark gray-to-black aerial mycelium grew. Hyphae were branched, septate, and brown and disarticulated into 0- to 1-septate arthrospores. Sporulation was induced by culturing on sterile horsetail tree (Casuarina equisetifolia) leaves. Conidia (12.79 ± 0.72 × 5.14 ± 0.30 µm) from pycnidia were one-celled, hyaline, and ovate. The internal transcribed spacer (ITS) region of ribosomal DNA was PCR amplified with primers ITS1 and ITS4 (2) and sequenced. The sequence (GenBank Accession No. HQ439174) showed 99% identity to Neoscytalidium dimidiatum (Penz.) Crous & Slippers (GenBank Accession No. GQ330903). On the basis of morphology and nucleotide-sequence identity, the isolates were identified as N. dimidiatum (1). Pathogenicity tests were conducted in two replicates by inoculating six surface-sterilized detached stems of pitaya with either mycelium or conidia. Mycelial plugs from 2-day-old cultures (incubated at 25°C under near UV) were inoculated to the detached stems after wounding with a sterile needle. Conidial suspensions (103 conidia/ml in 200 µl) were inoculated to nonwounded stems. Noninoculated controls were treated with sterile medium or water. Stems were then incubated in a plastic box at 100% relative humidity and darkness at 30°C for 2 days. The symptoms described above were observed on inoculated stems at 6 to 14 days postinoculation, whereas control stems did not develop any symptoms. N. dimidiatum was reisolated from symptomatic tissues. To our knowledge, this is the first report of N. dimidiatum causing stem canker of pitaya. References: (1) P. W. Crous et al. Stud. Mycol. 55:235, 2006. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, New York, 1990.
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BACKGROUND: We studied the combination of pemetrexed, a multi-targeted antifolate, and cetuximab, an mAb against the epidermal growth factor receptor, with radiotherapy in poor prognosis head and neck cancer. PATIENTS AND METHODS: Patients received pemetrexed on days 1, 22, and 43 on a dose-escalation scheme with starting level (0) 350 mg/m(2) (level -1, 200 mg/m(2); level +1, 500 mg/m(2)) with concurrent radiotherapy (2 Gy/day) and cetuximab in two separate cohorts, not previously irradiated (A) and previously irradiated (B), who received 70 and 60-66 Gy, respectively. Genetic polymorphisms of thymidylate synthase and methylenetetrahydrofolate reductase were evaluated. RESULTS: Thirty-two patients were enrolled. The maximum tolerated dose of pemetrexed was 500 mg/m(2) in cohort A and 350 mg/m(2) in cohort B. Prophylactic antibiotics were required. In cohort A, two dose-limiting toxicities (DLTs) occurred (febrile neutropenia), one each at levels 0 and +1. In cohort B, two DLTs occurred at level +1 (febrile neutropenia; death from perforated duodenal ulcer and sepsis). Grade 3 mucositis was common. No association of gene polymorphisms with toxicity or efficacy was evident. CONCLUSION: The addition of pemetrexed 500 mg/m(2) to cetuximab and radiotherapy is recommended for further study in not previously irradiated patients.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Adulto , Anciano , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/radioterapia , Cetuximab , Terapia Combinada , Relación Dosis-Respuesta a Droga , Femenino , Glutamatos/administración & dosificación , Glutamatos/efectos adversos , Guanina/administración & dosificación , Guanina/efectos adversos , Guanina/análogos & derivados , Neoplasias de Cabeza y Cuello/genética , Humanos , Masculino , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Persona de Mediana Edad , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/radioterapia , Pemetrexed , Polimorfismo Genético , Carcinoma de Células Escamosas de Cabeza y Cuello , Timidilato Sintasa/genéticaRESUMEN
Due to the risk of occult cervical metastasis, elective neck dissection (END) is recommended in the management of patients with early oral cavity squamous cell carcinoma (OSCC) and a clinically node-negative (cN0) neck. This paper presents a systematic review and meta-analysis of studies that recorded isolated regional recurrence (RR) in the pathologically node-negative neck dissection (pN0) neck following END in order to quantify the failure rate. Pubmed and Ovid databases were systematically searched for relevant articles published between January 2009 and January 2019. Studies reporting RR following END in patients with OSCC who had no pathological evidence of lymph node metastasis were eligible for inclusion in this meta-analysis. In addition, a selection of large head and neck units were invited to submit unpublished data. Search criteria produced a list of 5448 papers, of which 18 studies met the inclusion criteria. Three institutions contributed unpublished data. This included a total of 4824 patients with median follow-up of 34 months (2.8 years). Eight datasets included patients staged T1-T4 with RR 17.3% (469/2711), 13 datasets included patients staged T1-T2 with RR 7.5% (158/2113). Overall across all 21 studies, isolated neck recurrence was identified in 627 cases giving a RR of 13.0% (627/4824) on meta-analysis. Understanding the therapeutic effectiveness of END provides context for evaluation of clinical management of the cN0 in these patients. A pathologically negative neck does not guarantee against future recurrence.
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Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Humanos , Disección del Cuello , Estadificación de Neoplasias , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y CuelloRESUMEN
PURPOSE: RECIST have limitations when applied to potentially curable locally advanced squamous cell carcinoma of the head and neck (SCCHN). [¹8F]fluorodeoxyglucose-positron emission tomography (PET) scan may be useful in assessing treatment response and predicting patient outcome. PATIENTS AND METHODS: We studied patients with previously untreated stages III-IVb SCCHN treated with primary concurrent chemoradiotherapy on five prospective clinical trials. Response was assessed by clinical exam, computed tomography (CT), and PET portions of combined PET-CT scan â¼8 weeks after completion of chemoradiotherapy. RESULTS: Fifty-three patients were analyzed. Complete response (CR) was demonstrated in 42 patients (79%) by clinical exam, 15 (28%) by CT, and 27 (51%) by PET. CR as assessed by PET, but not as assessed by clinical exam or CT using RECIST, correlated significantly with progression-free status (PFS) (P < 0.0001). The 2-year PFS for patients with CR and without CR by PET was 93% and 48%, respectively (P = 0.0002). CONCLUSIONS: A negative PET scan on combined PET-CT after chemoradiotherapy is a powerful predictor of outcome in patients receiving curative chemoradiotherapy for SCCHN. PET-CT is indicated for response evaluation in this setting to improve the accuracy of post-treatment assessment by CT.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias de Cabeza y Cuello/terapia , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Adulto , Anciano , Carcinoma de Células Escamosas/patología , Terapia Combinada , Femenino , Fluorodesoxiglucosa F18 , Neoplasias de Cabeza y Cuello/patología , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Prospectivos , Radiofármacos , Dosificación Radioterapéutica , Tasa de Supervivencia , Resultado del Tratamiento , Adulto JovenRESUMEN
With the popularization and application of implant technology and its good clinical effect, clinicians focus on exploring diagnosis and treatment strategies that can reduce the difficulty and risk of implant treatment, decrease the treatment complications of patients, and improve the surgical acceptance of patients. The technology of alveolar ridge preservation has become the focus of clinical attention. Clinical trials also confirmed that alveolar ridge preservation technology could effectively slow down the absorption of alveolar crest after tooth extraction, so as to maintain the alveolar crest volume shape. Most previous reviews about alveolar ridge preservation focused on surgical procedures, materials application and selection of related procedures. The effect of various causes of tooth extraction on alveolar ridge preservation has not been reviewed. In this review article, the differences between alveolar ridge preservation in non-periodontitis and periodontitis teeth were analyzed histologically and morphologically, so as to provide a decision-making strategies for clinical application of alveolar ridge preservation at various tooth extraction sites.
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Pérdida de Hueso Alveolar , Proceso Alveolar , Aumento de la Cresta Alveolar , Periodontitis , Extracción Dental , Proceso Alveolar/cirugía , Humanos , Periodontitis/cirugía , Alveolo DentalRESUMEN
Oropharyngeal squamous cell carcinoma (OPSCC) incidence is increasing at a nearly epidemic rate, largely driven by the human papillomavirus (HPV). Despite the generally favorable clinical outcomes of patients with HPV driven (HPV+) OPSCC, a significant subset of HPV tumors associated with tobacco exposure have diminished treatment response and worse survival. The tumor immune microenvironment (TIME) has been shown to be a critical driver of treatment response and oncologic outcomes in OPSCC generally and HPV+ OPSCC more specifically. However, the impact of tobacco exposure on the TIME in OPSCC patients remains unclear. We analyzed the relationship between TIME, tobacco exposure and clinical outcomes in OPSCC patients (n = 143) with extensive tobacco exposure (median pack-years = 40). P16 overexpression, a surrogate marker of HPV association, was a strong predictor of relapse-free (RFS) and overall survival (OS) (p < 0.001, p < 0.001 respectively) regardless of tobacco exposure and associated strongly with differential infiltration of the tumor by both CD3 and CD8 lymphocytes measured via immunohistochemistry (p < 001, p < 0.001 respectively). CD3 and CD8 infiltration was a strong predictor of RFS and OS and associated strongly with disease stage (AJCC 8th Edition Staging Manual). Tobacco exposure correlated significantly (p < 0.001) with decreased CD8 infiltration in p16+ OPSCC tumors. Our findings demonstrate that the HPV+ OPSCC clinical outcomes are strongly correlated with the TIME, which is potentially modulated by tobacco exposure. Immunomodulatory strategies targeting this disease in smokers must take into consideration the potential modifying effects of tobacco exposure on treatment effectiveness and clinical outcomes.
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Antígenos CD8/metabolismo , Nicotiana/efectos adversos , Neoplasias Orofaríngeas/inducido químicamente , Neoplasias Orofaríngeas/metabolismo , Carcinoma de Células Escamosas/inducido químicamente , Carcinoma de Células Escamosas/inmunología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/virología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Orofaríngeas/inmunología , Neoplasias Orofaríngeas/virología , Papillomaviridae/fisiología , Estudios Retrospectivos , Riesgo , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/inmunologíaRESUMEN
MicroRNAs (miR) are small noncoding RNAs that are predicted to regulate up to 30% of protein-encoding genes. miR maturation requires functional microRNA machinery, including the Dicer protein. We review our experience with mucoepidermoid carcinoma (MEC) and characterize the prognostic value of Dicer expression. Expression of Dicer was assessed in 78 MEC by immunohistochemistry. Dicer expression was scored semiquantitatively and relative to the internal controls: large excretory/striated ducts or basal/parabasal layers of normal squamous epithelium (mucosa). Dicer scores were then correlated with clinical and pathologic parameters. Dicer over- and/or under-expression were more commonly seen in high-grade MEC (83%) than in low/intermediate grade MEC (35%; p=0.002) and in stage III/IV MEC (80%) than in stage I/II MEC (41%; p=0.04). Abnormal Dicer expression correlates with high-grade and advanced stage, acting as a univariate predictor of poor disease-specific survival (DSS) in MEC. Age and stage were independent predictors of poor DSS on multivariate analysis. Abnormal immunoexpression of Dicer in aggressive MEC suggests a role for miR and miR machinery in tumor progression.
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Carcinoma Mucoepidermoide/patología , Neoplasias de la Boca/patología , Ribonucleasa III/biosíntesis , Neoplasias de las Glándulas Salivales/patología , Adulto , Anciano de 80 o más Años , Carcinoma Mucoepidermoide/metabolismo , Niño , Estudios de Cohortes , Femenino , Humanos , Inmunohistoquímica , Masculino , MicroARNs , Persona de Mediana Edad , Neoplasias de la Boca/metabolismo , Neoplasias de las Glándulas Salivales/metabolismoRESUMEN
Genetic evidence suggests that mutations in the gamma(c) receptor subunit cause X-linked severe combined immunodeficiency (X-SCID). The gamma(c) subunit can be employed in receptor complexes for IL-2, -4, -7, -9, and -15, and the multiple signaling defects that would result from a defective gamma(c) chain in these receptors are proposed to cause the severe phenotype of X-SCID patients. Interestingly, gene disruption of either IL-7 or the IL-7 receptor (IL-7R) alpha subunit in mice leads to immunological defects that are similar to human X-SCID. These observations suggest the functional importance of gamma(c) in the IL-7R complex. In the present study, structure/function analyses of the IL-7R complex using a chimeric receptor system demonstrated that gamma(c) is indeed critical for IL-7R function. Nonetheless, only a limited portion of the cytoplasmic domain of gamma(c) is necessary for IL-7R signal transduction. Furthermore, replacement of the gamma(c) cytoplasmic domain by a severely truncated erythropoeitin receptor does not affect measured IL-7R signaling events. These findings support a model in which gamma(c) serves primarily to activate signal transduction by the IL-7R complex, while IL-7R alpha determines specific signaling events through its association with cytoplasmic signaling molecules. Finally, these studies are consistent with the hypothesis that the molecular pathogenesis of X-SCID is due primarily to gamma(c)-mediated defects in the IL-7/IL-7R system.
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Antígenos CD/metabolismo , Receptores de Interleucina/metabolismo , Inmunodeficiencia Combinada Grave/etiología , Inmunodeficiencia Combinada Grave/genética , Cromosoma X/genética , Antígenos CD/química , Linfocitos B/efectos de los fármacos , Polaridad Celular , Citocinas/farmacología , Proteínas de Unión al ADN/metabolismo , Dimerización , Ligamiento Genético , Humanos , Conformación Proteica , Proteínas Tirosina Quinasas/metabolismo , Receptores de Interleucina/química , Receptores de Interleucina-7 , Transducción de Señal , Relación Estructura-Actividad , Factores de Transcripción/metabolismoRESUMEN
A systematic investigation of the reduction of aqueous Na(2)WO(4) with aqueous NaBH(4) at ambient temperatures reveals the formation of several lower valent tungsten oxides such as the tetragonal (x < 0.38) and cubic (x > 0.43) tungsten bronzes Na(x)()WO(3) and the binary oxides WO(2) and W(24)O(68). The nature of the product formed is influenced both by the (i) reducing power of NaBH(4), which is controlled by the volume and concentration of the borohydride and the reaction pH, and (ii) the degree of condensation of the tungstate ions, which is controlled by the reaction pH. Although the reducing power of NaBH(4) increases with decreasing pH, an increasing degree of condensation of the tungstate tends to lower the degree of reduction in many instances. The as-prepared samples are amorphous as revealed by X-ray diffraction and crystallize around 450 degrees C as revealed by differential scanning calorimerty. The tungsten bronzes undergo interesting crystal-chemical changes with the temperature of heating.
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Three insect cell lines, SL-7B cells derived from Spodoptera litura, Sf9, and High Five (Hi-5) cells, were used for the production of pro-hepatocyte growth factor (pro-HGF). Cells were cultured and then infected with a recombinant HGF-containing baculovirus in a serum-free medium. In SL-7B cells, pro-HGF is synthesized and excreted from the cells and late in infection is converted to a heterodimeric form of HGF even when the cells are grown in serum free medium. Conversion of a single-chain form of HGF (pro-HGF) into an HGF heterodimer was unexpected, as pro-HGF is normally cleaved by a serum protease called HGF activator. The proliferation activity of heparin-affinity-purified HGF from serum-free culture supernatant of SL-7B cells is comparable to that obtained from HGF converted by serum proteases, suggesting that SL-7B cells produce a functionally analogous protease to correctly process pro-HGF. This work reports, for the first time, on the feasibility of properly processing pro-HGF to form functional HGF by proteases from invertebrate cells in serum-free media. Avoiding the supplementation of sera provides the advantages of a low production cost, zero contamination of infectious agents from sera, and simple downstream product purification. Experimental results further demonstrate that the conversion of pro-HGF by insect cells is cell-line-dependent, because proteases in Hi-5 or Sf9 cells could not process pro-HGF as efficiently and properly as those in SL-7B cells.
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Baculoviridae/genética , Factor de Crecimiento de Hepatocito/genética , Factor de Crecimiento de Hepatocito/metabolismo , Ingeniería de Proteínas/métodos , Spodoptera/citología , Animales , Biotecnología/métodos , División Celular/efectos de los fármacos , Línea Celular , Cromatografía de Afinidad , Medio de Cultivo Libre de Suero , Vectores Genéticos , Heparina/metabolismo , Factor de Crecimiento de Hepatocito/aislamiento & purificación , Factor de Crecimiento de Hepatocito/farmacología , Precursores de Proteínas/metabolismo , Ratas , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacología , Spodoptera/genética , Spodoptera/virologíaRESUMEN
A purification process was developed to obtain highly pure rVP2H particles, formed by a structural protein (VP2) of the infectious bursal disease virus (IBDV) with six additional histidine residues at its C-terminus. The ultimate goal was the development of an efficient subunit vaccine against IBDV infection. The particles within the infected High-Five (Hi-5) cell lysates were partially purified by employing immobilized metal ion (Ni(2+)) affinity chromatography (IMAC). The initial step could recover approximately 85% of immunoreactive rVP2H proteins but failed to separate the rVP2H particles from the free rVP2H proteins or its degraded products. To separate the particulate form from the free form of rVP2H, an additional step was added, which used either gel filtration chromatography or CsCl density gradient ultracentrifugation. Both were able to produce extremely pure rVP2H particles with a buoyant density close to 1.27 g/cm(3). However, the former method can process a larger sample volume than does the latter. By integrating IMAC and gel filtration chromatography, 1 mg of extremely pure rVP2H particles was routinely obtained from a 500 mL Hi-5 cell culture broth. The separation of the particulate form from the free form of rVP2H proteins exposes their respective immunogenicity to induce the virus-neutralizing antibodies and the ability to protect chickens from IBDV infection. Additionally, the abundant quantities of pure rVP2H particles coupled with their uniform dimensions facilitates an understanding of higher order structure of the immunogenic particles and can therefore result in improved vaccines against the virus.
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Cromatografía de Afinidad/métodos , Cromatografía en Gel/métodos , Virión/aislamiento & purificación , Baculoviridae/aislamiento & purificación , Western Blotting , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Proteínas Recombinantes/aislamiento & purificación , UltracentrifugaciónRESUMEN
A partial DNA sequence of cytochrome b gene was used to identify the remains of endangered animals and species endemic to Taiwan. The conservation of animals species included in this study were: the formosan gem-faced civets, leopard cats, tigers, clouded leopards, lion, formosan muntjacs, formosan sika deers, formosan sambars, formosan serows, water buffalo, formosan pangolins and formosan macaques. The control species used included domestic cats, domestic dogs, domestic sheeps, domestic cattles, domestic pigs and humans. Heteroplasmy was detected in the formosan macaque, domestic pig and domestic cats. The frequencies of heteroplasmy in these animals were about 0.25% (1 in 402bp). Sequences were aligned by Pileup program of GCG computer package, and the phylogenetic tree was constructed by the neighbor-joining method. The results of sequence comparison showed that the percentage range of sequence diversity in the same species was from 0.25 to 2.74%, and that between the different species was from 5.97 to 34.83%. The results of phylogenetic analysis showed that the genetic distance between the different species was from 6.33 to 40.59. Animals of the same species, both the endangered animal species and domestic animals, were clustered together in the neighbor-joining tree. Three unknown samples of animal remains were identified by this system. The partial sequence of cytochrome b gene adopted in this study proved to be usable for animal identification.
Asunto(s)
Animales Salvajes/genética , Grupo Citocromo b/genética , Especificidad de la Especie , Animales , Animales Salvajes/clasificación , Secuencia de Bases , ADN/clasificación , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , TaiwánRESUMEN
A randomized, prospective, double-blind study comparing benzyl alcohol with epinephrine, 1:100,000 (BA), and lidocaine with epinephrine, 1:100,000 (LID), as local anesthetics was carried out on adult patients with simple lacerations. The two study groups were compared for pain of infiltration (100 mm visual analog scale) and need for additional anesthesia. Pain scores were compared by a Mann Whitney Independent Rank Sum test and need for additional anesthesia by a Fishers Exact test. A total of 52 subjects (26 per group) were analyzed. The groups were similar in demographics and wound characteristics. The median pain score for BA, 7.5 mm, was less than for LID, 19.5 mm (p = 0.049). Although more patients receiving BA required additional anesthesia as compared to LID (8/26 versus 2/26), this difference did not reach statistical significance. BA is a reasonable alternative local anesthetic to LID for patients who are allergic to LID.