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1.
Phys Rev Lett ; 129(24): 242502, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36563237

RESUMO

ß decay of proton-rich nuclei plays an important role in exploring isospin mixing. The ß decay of ^{26}P at the proton drip line is studied using double-sided silicon strip detectors operating in conjunction with high-purity germanium detectors. The T=2 isobaric analog state (IAS) at 13 055 keV and two new high-lying states at 13 380 and 11 912 keV in ^{26}Si are unambiguously identified through ß-delayed two-proton emission (ß2p). Angular correlations of two protons emitted from ^{26}Si excited states populated by ^{26}P ß decay are measured, which suggests that the two protons are emitted mainly sequentially. We report the first observation of a strongly isospin-mixed doublet that deexcites mainly via two-proton decay. The isospin mixing matrix element between the ^{26}Si IAS and the nearby 13 380-keV state is determined to be 130(21) keV, and this result represents the strongest mixing, highest excitation energy, and largest level spacing of a doublet ever observed in ß-decay experiments.

2.
Zhonghua Wai Ke Za Zhi ; 60(1): 22-26, 2022 Jan 01.
Artigo em Chinês | MEDLINE | ID: mdl-34954942

RESUMO

Pancreatic cancer is a malignant tumor with very poor prognosis. In the past decade, the surgical technique has made significant progress, but it has not brought desired effect in improving the survival outcome of pancreatic cancer patients. With the development of the concept of cancer treatment and the emergence of precision medicine, the surgical centered multidisciplinary treatment and collaborative diagnosis and treatment mode has gradually become the mainstream. Accurate preoperative assessment of pancreatic cancer has become a breakthrough for further improving the prognosis of patients with pancreatic cancer. From the perspective of precise assessment, this paper mainly summarized the status and progress on the following four aspects: the preoperative diagnosis and staging, the resectability evaluation, the neoadjuvant therapy strategy and efficacy evaluation of neoadjuvant therapy in pancreatic cancer, and also discussed the shortcomings and challenges in the field of precise assessment, finally in order to make the preoperative assessment of pancreatic cancer more precise and standard, and to provide useful reference for future research work.


Assuntos
Neoplasias Pancreáticas , Humanos , Terapia Neoadjuvante , Estadiamento de Neoplasias , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Prognóstico
3.
Phys Rev Lett ; 126(15): 152502, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33929212

RESUMO

A new α-emitting isotope ^{214}U, produced by the fusion-evaporation reaction ^{182}W(^{36}Ar,4n)^{214}U, was identified by employing the gas-filled recoil separator SHANS and the recoil-α correlation technique. More precise α-decay properties of even-even nuclei ^{216,218}U were also measured in the reactions of ^{40}Ar, ^{40}Ca beams with ^{180,182,184}W targets. By combining the experimental data, improved α-decay reduced widths δ^{2} for the even-even Po-Pu nuclei in the vicinity of the magic neutron number N=126 are deduced. Their systematic trends are discussed in terms of the N_{p}N_{n} scheme in order to study the influence of proton-neutron interaction on α decay in this region of nuclei. It is strikingly found that the reduced widths of ^{214,216}U are significantly enhanced by a factor of two as compared with the N_{p}N_{n} systematics for the 84≤Z≤90 and N<126 even-even nuclei. The abnormal enhancement is interpreted by the strong monopole interaction between the valence protons and neutrons occupying the π1f_{7/2} and ν1f_{5/2} spin-orbit partner orbits, which is supported by the large-scale shell model calculation.

4.
Zhonghua Yu Fang Yi Xue Za Zhi ; 52(3): 287-291, 2018 Mar 06.
Artigo em Chinês | MEDLINE | ID: mdl-29973009

RESUMO

Objective: Evaluate GII.4 norovirus infection and blocking effects of serum antibodies against HBGAs binding to GII.4 norovirus of population in oyster culture area, provide references for screening of fully human monoclonal antibody. Methods: Using a random survey method to collect blood and saliva samples in oyster culture area, select serum samples from the inland region of Guangdong as control group. Identification of salivary HBGA receptor phenotype and detection of serum antibody levels between two areas by ELISA. A vitro neutralization model was to determine the efficiency of serum antibodies blocking GII.4 norovirus and HBGA receptors binding. Results: The age were (50.68 ± 15.17), (52.52 ± 15.90) and (51.37 ± 13.32) years old of 2015, 2016 in experimental group, and in control group, respectively. Males accounted for 5.9% (70/195), 36.6%(60/164), 40.8% (69/169) (χ(2)=0.93, P=0.334). The mean value of serum antibodies Absorbance value was 2.521±0.05 of 2015 and was 2.583±0.045 of 2016 in oyster culture area, the mean value was 2.249±0.05 in control group, there was a statistical difference among three group (F=13.28, P<0.001). The antibody prevalence in the three groups was 100%. BT50 geometric mean titer (GMT) of oyster culture area in 2015 was 423.1±40.11, culture group was 248.2±25.63, there was a statistical difference (t=3.73, P<0.001). Conclusion: The population in oyster culture area does have more chance of exposure and infection GII.4 norovirus, Serum antibody of blocking ability in oyster culture areas is better than the general population in inland city. Suggesting that the population is more immunity resistant infected GII.4 norovirus.


Assuntos
Anticorpos Bloqueadores/sangue , Infecções por Caliciviridae/prevenção & controle , Norovirus/imunologia , Receptores Virais/metabolismo , Adulto , Idoso , Animais , Infecções por Caliciviridae/imunologia , Estudos de Casos e Controles , China , Exposição Ambiental/efeitos adversos , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ostreidae
5.
J R Army Med Corps ; 164(2): 69-71, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29431146

RESUMO

BACKGROUND: Idiopathic sudden sensorineural hearing loss (ISSNHL) is defined as a 30-decibel (dB) loss in hearing over three contiguous frequencies within 3 days. The cause remains unknown, and there is currently no consensus in the literature as to how it is best treated. Conventional treatment in our unit comprises steroids, pentoxyphiline and dextran, with the potential addition of hyperbaric oxygen therapy (HBOT). METHODS: A prospective randomised trial was performed on all soldiers diagnosed with ISSNHL in our institution from 1 January 2007 to 31 December 2016. Participants were randomly allocated to one of two groups. Group A was treated with conventional treatment plus HBOT. Group B was treated with conventional treatment only. Data collection included age, gender, clinical symptoms, pure-tone audiometry results and treatment outcome. RESULTS: 60 participants were enrolled (53 male, 7 female) with ages ranging from 18 to 65 years (mean age of 30.3). No significant differences were observed in the baseline characteristics between the two groups, including gender, age, site, associated symptoms, duration of symptoms and severity of hearing loss. Hearing recovery using Siegel's criteria on days 8 and 13 showed no significant differences between treatment groups. However, the hearing recovery on day 180 was significantly better in those who received the conventional treatment plus HBOT (P<0.05). Additionally, no significant side effects were observed in either group. CONCLUSIONS: HBOT plus existing conventional treatment was associated with a better outcome than conventional treatment alone. We would recommend the addition of HBOT is recommended as a first-line treatment modality for all soldiers presenting with ISSNHL.


Assuntos
Perda Auditiva Neurossensorial/terapia , Oxigenoterapia Hiperbárica , Militares , Doença Aguda , Adolescente , Adulto , Idoso , Terapia Combinada , Dextranos/uso terapêutico , Quimioterapia Combinada , Feminino , Glucocorticoides/uso terapêutico , Audição , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Pentoxifilina/uso terapêutico , Substitutos do Plasma/uso terapêutico , Prednisolona/uso terapêutico , Estudos Prospectivos , Recuperação de Função Fisiológica , Taiwan , Fatores de Tempo , Resultado do Tratamento , Vasodilatadores/uso terapêutico , Adulto Jovem
6.
Niger J Clin Pract ; 20(9): 1213-1215, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29072250

RESUMO

Retropharyngeal emphysema is usually secondary to trauma, iatrogenic injury, and obstructive respiratory diseases. Without prompt and adequate treatment, severe complication such as airway compromise may occur. Spontaneous retropharyngeal emphysema, defined by the presence of free air in the retropharyngeal space without any precipitating cause, is a rare clinical condition in pediatric otolaryngology. The predominant symptoms are sore throat, odynophagia, dysphagia, and neck pain. Here, we report a case of spontaneous retropharyngeal emphysema.


Assuntos
Enfisema/diagnóstico por imagem , Cervicalgia/etiologia , Faringe/patologia , Espaço Retroperitoneal/diagnóstico por imagem , Adolescente , Humanos , Masculino , Doenças Faríngeas , Tomografia Computadorizada por Raios X
7.
Zhonghua Liu Xing Bing Xue Za Zhi ; 37(2): 139-63, 2016 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-26917506

RESUMO

In order to promote the prevention and control programs on rabies in our country, to regulate the prevention and disposition of rabies and to reduce the deaths caused by rabies, the Chinese Center for Disease Control and Prevention has organized a panel of experts, in the reference with Guidelines issued by WHO, American Advisory Committee on Immunization Practices, and the latest research progress from home and abroad, and compiled this document-"Technical Guidelines for Human Rabies Prevention and Control (2016)". The Guidelines conducted a systematic review on the etiology, clinical characteristics, laboratory diagnosis, epidemiology of rabies and provided evidence on varieties, mechanisms, effects, side-effects and security of rabies vaccine, as well as on other preparations on passive immunity of its kind, on methods related to prevention and disposition of exposure etc, finally to have come up with the recommendation on the above mentioned various techniques. The guidelines will be used by staff working on prevention and control of rabies from the Center for Disease Control and Prevention at all levels, from the departments of outpatient and divisions of infection and emergency control in all the medical institutions. The guideline will be updated and revised, following the research progress from home and abroad.


Assuntos
Guias de Prática Clínica como Assunto , Raiva/prevenção & controle , China , Humanos , Vacina Antirrábica , Vacinação
8.
Eur Rev Med Pharmacol Sci ; 18(9): 1411-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24867522

RESUMO

OBJECTIVE: Previous study showed that peripheral-type benzodiazepine receptors (PBRs) are expressed in human mesenchymal stem cells (hMSCs) and diazepam was found to inhibit hMCSs viability in high concentration. Midazolam, a benzodiazepine derivative, is widely used as an intravenous sedative in hospital. Peripheral-type benzodiazepine receptors (PBRs) affect a broad spectrum of cellular functions. We tested the cell viability and osteogenic differentiation of hMSCs. PATIENTS AND METHODS: Bone marrow was collected from 12 patients during the operation of spine internal fixation. Cultivated with basal medium, the hBMSCs were incubated with or without midazolam (0.1, 1, 5, 10, 15, 20 µM, respectively). Cell viability were tested with MTS assay after 2, 4, 6 hours respectively. Cell morphology was observed and recorded at 6 hour. After cultivated with osteogentic medium, the hBMSCs were incubated with or without midazolam (5, 10, 15, 20 µM, respectively). Alkaline phosphatase (ALP) activity and alizarin red S staining were measured. Cultivated with osteogentic medium with or without treatment of 15 µM midazolam, the mRNA expression of ALP, type 1 collagen (COL1), Runx2 and PPARγ was analyzed by real-time RT-PCR. RESULTS: The treatments of midazolam inhibited cell viability to 85%-16% respectively (p < 0.05). Rounded up phenomenon with floating cells, Membrane-blebbed cells and cytoplasmic contraction were observed after 10, 15 or 20 µM midazolam treatment. The ALP activity and Calcium deposition of hBMSCs exposed to 15 and 20 µM midazolam was significantly inhibited at 7, 14 and 21 days (p < 0.05). And the mRNA expression of ALP, COL1 and PPARγ was significantly suppressed in the hBMSCs cultured with 15 µM midazolam (p < 0.05). CONCLUSIONS: Midazolam exert negative effect on cell viability and osteogenic differentiation of cultured hBMSCs. During sedation in critical care, the use of midazolam may suppress activity of hBMSCs.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Hipnóticos e Sedativos/toxicidade , Células-Tronco Mesenquimais/efeitos dos fármacos , Midazolam/toxicidade , Osteogênese/efeitos dos fármacos , Adulto , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Células da Medula Óssea/metabolismo , Cálcio/metabolismo , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Relação Dose-Resposta a Droga , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Células-Tronco Mesenquimais/metabolismo , Pessoa de Meia-Idade , PPAR gama/genética , PPAR gama/metabolismo , RNA Mensageiro/metabolismo , Fatores de Tempo
9.
JNMA J Nepal Med Assoc ; 52(195): 902-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26982664

RESUMO

INTRODUCTION: The purpose of this study was to analyze the risk factors affecting precancerous lesions, and cancer of oral cavity, and to assess efficacy of visual screening for oral mucosal lesions. METHODS: The medical records of patients older than 30 years of age with history of habitual cigarette smoking or betel quid chewing that received screening for oral mucosal lesions between January 2012 and December 2012 were retrospectively reviewed. The patients' age, gender, risk factors, screening findings, and histopathology results of biopsy were included for further analysis. RESULTS: A total of 1341 patients were enrolled in this study. There were 1080 males and 261 females ranging from 30 to 96 years of age, with a mean age of 53.9±13.6 years. After screening, 226 (16.9%) were found to be positive of oral lesions. Among these 226 patients, 69 (30.5%) underwent biopsy under local anesthesia, and the histopathology showed malignancy in 13 (5.8%). All of the confirmed malignant cases were squamous cell carcinoma. Among them, 12 received further staging examination and one was lost to follow-up resulting in unknown stage. The early stage oral cavity cancer (stage I and II) accounted for 84.6% (11/13). CONCLUSIONS: The detection rate of early stage oral cavity cancer in our study was reasonable. Therefore, visual screening for oral cavity cancer is recommended for patients with habitual cigarette smoking or betel quid chewing.


Assuntos
Carcinoma de Células Escamosas , Detecção Precoce de Câncer , Neoplasias Bucais , Boca/patologia , Lesões Pré-Cancerosas , Adulto , Idoso , Biópsia/métodos , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/patologia , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/epidemiologia , Neoplasias Bucais/patologia , Estadiamento de Neoplasias , Exame Físico/métodos , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/epidemiologia , Lesões Pré-Cancerosas/patologia , Estudos Retrospectivos , Fatores de Risco , Fumar/epidemiologia , Estatística como Assunto , Taiwan/epidemiologia
11.
Cell Death Differ ; 18(10): 1651-63, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21660051

RESUMO

Oxidative stress and nitrosative stress are both suggested to be involved in cardiac ischemia-reperfusion (I/R) injury. Using time-lapse confocal microscopy of cardiomyocytes and high-affinity O(2)(-•) and Zn(2+) probes, this study is the first to show that I/R, reactive oxygen species (ROS), and reactive nitrogen species (RNS) all cause a marked increase in the [O(2)(-•)](i), resulting in cytosolic and mitochondrial Zn(2+) release. Exposure to a cell-penetrating, high-affinity Zn(2+)(i) chelator, TPEN, largely abolished the Zn(2+)(i) release and markedly protected myocytes from I/R-, ROS-, RNS-, or Zn(2+)/K(+) (Zn(2+)(i) supplementation)-induced myocyte apoptosis for at least 24 h after TPEN removal. Flavonoids and U0126 (a MEK1/2 inhibitor) largely inhibited the myocyte apoptosis and the TPEN-sensitive I/R- or Zn(2+)(i) supplement-induced persistent extracellular signal-regulated kinase 1 and 2 (ERK1/2) phosphorylation, dephosphorylation of p-Ser9 on glycogen synthase kinase 3ß (GSK-3ß), and the translocation into and accumulation of p-Tyr216 GSK-3ß and p53 in, the nucleus. Silencing of GSK-3ß or p53 expression was cardioprotective, indicating that activation of the ERK-GSK-3ß-p53 signaling pathway is involved in Zn(2+)-sensitive myocyte death. Moreover, the ERK-dependent Noxa-myeloid cell leukemia-1 (Mcl-1) pathway is also involved, as silencing of Noxa expression was cardioprotective and U0126 abolished both the increase in Noxa expression and in Mcl-1 degradation. Thus, acute upstream Zn(2+)(i) chelation at the start of reperfusion and the use of natural products, that is, flavonoids, may be beneficial in the treatment of cardiac I/R injury.


Assuntos
Quinase 3 da Glicogênio Sintase/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Zinco/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Butadienos/farmacologia , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Células Cultivadas , Quinase 3 da Glicogênio Sintase/genética , Glicogênio Sintase Quinase 3 beta , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides , Traumatismo por Reperfusão Miocárdica/genética , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Nitrilas/farmacologia , Fosforilação/efeitos dos fármacos , Transporte Proteico/genética , Transporte Proteico/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Ratos , Proteína Supressora de Tumor p53/genética
12.
Clin Exp Allergy ; 40(10): 1482-90, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20701609

RESUMO

BACKGROUND: The prevalence of allergic diseases has increased in the past decades. It is unknown whether expression of certain microRNAs (miRNAs) in neonatal leucocytes is correlated to IgE production and/or allergic diseases. OBJECTIVE: This study investigated the association of miRNA expression in neonatal leucocytes with cord blood IgE (CBIgE) elevation and development of allergic disease. METHODS: We screened for the expression of a panel of 157 miRNAs in mononuclear leucocytes from human umbilical cord blood (CB) samples with elevated CBIgE and tracked the association of down-regulated miRNA expression to the miRNA-targeted gene expression and to children with allergic rhinitis (AR). RESULTS: Among the initial screen of 10 CB samples with elevated CBIgE, expression of eight of the 157 miRNAs was low. Of these eight down-expressed miRNAs, three remained down-regulation in a validation with other 20 CB samples, and two of the three miRNAs, miR-21 and miR-126, were significantly lower in monocytes from AR children. Further analysis of mRNA expression of the miR-21-targeted genes identified that TGFBR2 expression on monocytes was significantly up-regulated in CB with elevated CBIgE, and in AR patients. Transfection of miR-21 precursor into monocytes from patients with AR increased miR-21 expression and decreased TGFBR2 expression. CONCLUSION: This study demonstrated the first in the literature that lower miR-21 expression in CB and increased TGFBR2 expression is associated with antenatal IgE production and development of AR.


Assuntos
Hipersensibilidade/genética , Imunoglobulina E/sangue , MicroRNAs/sangue , Rinite/genética , Western Blotting , Regulação para Baixo , Sangue Fetal/imunologia , Imunofluorescência , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Hipersensibilidade/sangue , Hipersensibilidade/imunologia , Técnicas Imunoenzimáticas , Imunoglobulina E/genética , Imunoglobulina E/imunologia , Recém-Nascido , Leucócitos/imunologia , MicroRNAs/imunologia , Monócitos/imunologia , Monócitos/metabolismo , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Serina-Treonina Quinases/imunologia , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/biossíntese , Receptores de Fatores de Crescimento Transformadores beta/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rinite/sangue , Rinite/imunologia
14.
Clin Exp Allergy ; 37(5): 680-7, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17456215

RESUMO

BACKGROUND: Genetic heritability and maternal atopy have been correlated to antenatal IgE production, but very few studies have studied gene-maternal atopy interaction on antenatal IgE production. This study investigated the interaction of CTLA-4 polymorphism with prenatal factors on the elevation of cord blood IgE (CBIgE). METHODS: Pregnant women were antenatally recruited for collection of prenatal environmental factors by a questionnaire. Umbilical cord blood samples were collected for CBIgE detection by fluorescence-linked enzyme assay and CTLA-4 polymorphism measurement by restriction fragment length polymorphism. RESULTS: A total of 1104 pregnant women initially participated in this cohort study, and 898 of them completed cord blood collection. 21.4% of the newborns had elevation of CBIgE (>or=0.5 kU/L). The CTLA-4+49A allele (P=0.021), maternal atopy (P<0.001) and gender (P=0.034), but not the CTLA-4+49G allele, -318C allele, -318T allele, parental smoking or paternal atopy, were significantly correlated with the CBIgE elevation in multivariate analysis. A dichotomous analysis of gene-maternal atopy interactions identified maternal atopy and CTLA-4+49A allele had an additive effect on the CBIgE elevation, especially prominent in male newborns; and in the absence of maternal atopy, CTLA-4+49GG genotype had a protective effect on CBIgE elevation in female newborns. CONCLUSIONS: Maternal but not paternal atopy has significant impacts on CBIgE elevation depending on gender and CTLA-4+49A/G polymorphism of newborns. Control of maternal atopy and modulation of CTLA-4 expression in the prenatal stage may be a target for the early prevention of perinatal allergy sensitization.


Assuntos
Antígenos CD/genética , Antígenos de Diferenciação/genética , Hipersensibilidade Imediata/genética , Imunoglobulina E/biossíntese , Polimorfismo Genético , Complicações na Gravidez/genética , Antígeno CTLA-4 , Pai , Feminino , Sangue Fetal/imunologia , Predisposição Genética para Doença , Humanos , Hipersensibilidade Imediata/imunologia , Recém-Nascido , Masculino , Mães , Polimorfismo de Fragmento de Restrição , Gravidez , Complicações na Gravidez/imunologia , Efeitos Tardios da Exposição Pré-Natal , Fatores Sexuais
15.
Mar Pollut Bull ; 44(5): 383-7, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12146820

RESUMO

Caffeine has been detected in Boston Harbor seawater with concentrations ranging from 140 to 1600 ng l(-1), and in Massachusetts Bay seawater at concentrations from 5.2 to 71 ng l(-1). Sources of caffeine appear to be anthropogenic with higher concentrations in the seawater of Boston's inner harbor and in freshwater sources to the harbor. Charles River water and Deer Island sewage treatment plant effluent, the two major sources of freshwater to the harbor, contained 370 and 6700 ng l(-1) of caffeine, respectively, in 1998. Sewage influent and effluent concentrations appear to be consistent with consumption estimates of caffeinated beverages for the Boston area and total organic carbon removal targets for treated sewage. Caffeine was inversely correlated to salinity in a transect from the mouth of Boston Harbor to Stellwagen Basin, indicating it may be a useful chemical tracer of anthropogenic inputs to marine systems.


Assuntos
Cafeína/análise , Estimulantes do Sistema Nervoso Central/análise , Poluentes da Água/análise , Bebidas , Boston , Monitoramento Ambiental , Esgotos/química , Cloreto de Sódio
16.
J Bone Joint Surg Br ; 84(3): 457-61, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12002511

RESUMO

Extracorporeal shock-wave (ESW) treatment has been shown to be effective in promoting the healing of fractures. We aimed to determine whether ESW could enhance the growth of bone-marrow osteoprogenitor cells. We applied ESW to the left femur of rats 10 mm above the knee at 0.16 mJ/mm2 in a range of between 250 and 2000 impulses. Bone-marrow cells were harvested after ESW for one day and subjected to assessment of colony-forming unit (CFU) granulocytes, monocytes, erythocytes, megakaryocytes (CFU-Mix), CFU-stromal cells (CFU-S) and CFU-osteoprogenitors (CFU-O). We found that the mean value for the CFU-O colonies after treatment with 500 impulses of ESW was 168.2 CFU-O/well (SEM 11.3) compared with 88.2 CFU-O/well (SEM 7.2) in the control group. By contrast, ESW treatment did not affect haematopoiesis as shown by the CFU-Mix (p = 0.557). Treatment with 250 and 500 impulses promoted CFU-O, but not CFU-Mix formations whereas treatment with more than 750 impulses had an inhibiting effect. Treatment with 500 impulses also enhanced the activity of bone alkaline phosphatase in the subculture of CFU-O (p<0.01), indicating a selective promotion of growth of osteoprogenitor cells. Similarly, formation of bone nodules in the long-term culture of bone-marrow osteoprogenitor cells was also significantly enhanced by ESW treatment with 500 impulses. The mean production of TGF-beta1 was 610 pg/ml (SEM 84.6) in culture supernatants from ESW-treated rats compared with 283 pg/ml (SEM 36.8) in the control group. Our findings suggest that optimal treatment with ESW could enhance rat bone-marrow stromal growth and differentiation towards osteoprogenitors presumably by induction of TGF-beta1.


Assuntos
Células da Medula Óssea/citologia , Diferenciação Celular , Ondas de Choque de Alta Energia , Osteoblastos/citologia , Células Estromais/citologia , Fator de Crescimento Transformador beta/biossíntese , Fosfatase Alcalina/metabolismo , Animais , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Células-Tronco Hematopoéticas/citologia , Masculino , Osteoblastos/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Crescimento Transformador beta1
17.
Biochem Biophys Res Commun ; 287(3): 648-55, 2001 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-11563844

RESUMO

Physical shock wave (SW) has shown effectiveness on promotion of bone growth. We have recently demonstrated that SW could promote bone marrow stromal cell differentiation toward osteoprogenitor associated with induction of TGF-beta1. We have further demonstrated that SW-induced membrane hyperpolarization and Ras activation acted an early signal for the osteogenesis in human bone marrow stromal cells. An optimal dose of SW treatment at 0.16 mJ/mm(2) for 500 impulses induced a rapid membrane hyperpolarization in 5 min, activation of Ras in 30 min, and cell proliferation in 2 days. The SW-promoted cell growth was related to osteogenesis as demonstrated by increase of bone alkaline phosphatase activity in 6 days and osteocalcin mRNA expression in 12 days. In support that SW-induced Ras activation mediated osteogenesis of human bone marrow stromal cells, we further demonstrated that transfection of bone marrow stromal cells with a dominant negative Ras mutant (Asn-17 ras(H)) abrogated the SW enhancement of osteogenic transcription factor (CBFA1) activation, osteocalcin mRNA expression, and bone nodule formations. These results suggest that physical SW promotes bone marrow stromal cell differentiation toward osteogenic lineage via membrane hyperpolarization, followed by Ras activation and specific osteogenic transcription factor CBFA1 expression. A link between physical SW and biomembrane perturbation-mediated Ras activation may highlight how noninvasive physical agents could be used to promote fracture healing and to rescue patients with osteoporosis and osteopenic disorders in the future.


Assuntos
Células da Medula Óssea/metabolismo , Ondas de Choque de Alta Energia , Proteínas de Neoplasias , Osteogênese , Proteínas ras/metabolismo , Divisão Celular , Linhagem Celular , Membrana Celular , Sobrevivência Celular , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core , Ativação Enzimática , Genes Dominantes , Humanos , Cinética , Potenciais da Membrana , Mutação , RNA Mensageiro/metabolismo , Transdução de Sinais , Fatores de Tempo , Fatores de Transcrição/metabolismo , Transfecção , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta1 , Proteínas ras/genética
18.
Brain Res ; 911(2): 105-15, 2001 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-11511377

RESUMO

In this investigation, changes of mechanical- (MEP) and laser-evoked potentials (LEP) in rat primary somatosensory cortex during the course of pentobarbital (PB) anesthesia were examined. Temporal analysis of changes in the magnitude and latency of MEP and LEP, EEG activity, gross motor behaviors, and the tail flick response following laser stimulation before, during, and after PB administration (50 mg/kg, i.p.) was performed and correlated in chronically implanted rats. During the wakeful condition, there were two major cortical components each following mechanical stimulation (MEP1 and MEP2, n=17) and laser stimulation (LEP1 and LEP2, n=10), respectively. After PB administration, the positive peak in MEP1 was enhanced, and all other components disappeared. These components returned with different time courses. Two hours after PB administration, when the rat had spontaneous movements and flexor reflexes, LEP2 showed reversed polarity. MEP2 returned gradually 3 h after PB administration when the rat regained its ability to execute coordinated movements. After 4 h, LEP1 began to reappear and LEP2 returned to its negative polarity. We found that PB facilitated Abeta fiber-related cortical evoked potential (MEP1), while differentially inhibited Adelta and C fiber-related components (MEP2, LEP1 and LEP2). Characterization of these anesthesia-induced changes in cortical output may be useful in studying the neural basis of tactile and pain sensations.


Assuntos
Potenciais Somatossensoriais Evocados/fisiologia , Temperatura Alta/efeitos adversos , Nociceptores/fisiologia , Dor/fisiopatologia , Córtex Somatossensorial/fisiologia , Tato/fisiologia , Adjuvantes Anestésicos/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Eletroencefalografia/efeitos dos fármacos , Potenciais Somatossensoriais Evocados/efeitos dos fármacos , Lasers/efeitos adversos , Masculino , Movimento/efeitos dos fármacos , Movimento/fisiologia , Fibras Nervosas/efeitos dos fármacos , Fibras Nervosas/fisiologia , Fibras Nervosas Mielinizadas/efeitos dos fármacos , Fibras Nervosas Mielinizadas/fisiologia , Nociceptores/efeitos dos fármacos , Medição da Dor/efeitos dos fármacos , Pentobarbital/farmacologia , Estimulação Física , Ratos , Ratos Wistar , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia , Reflexo/efeitos dos fármacos , Reflexo/fisiologia , Córtex Somatossensorial/efeitos dos fármacos , Tato/efeitos dos fármacos , Vigília/fisiologia
19.
Tex Heart Inst J ; 28(1): 63-4, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11330746

RESUMO

Two patients were referred to our hospital with constrictive pericarditis approximately 1 year after undergoing mitral valve repair at another institution. Both repairs had included the use of a pericardial substitute, Marlex mesh, to prevent adhesion and to facilitate possible reoperations. Computed tomography and cardiac catheterization were used to establish the diagnosis of constrictive pericarditis. During surgery, dense, thickened fibrous tissue, the result of a Marlex mesh-related reaction, was found tightly adhered to the epicardium in each of the patients. It appeared that the Marlex mesh, which had been inserted to facilitate reoperation, had contributed to the development of constrictive pericarditis.


Assuntos
Reação a Corpo Estranho/etiologia , Pericardite Constritiva/etiologia , Pericárdio/cirurgia , Polipropilenos , Complicações Pós-Operatórias/etiologia , Telas Cirúrgicas , Feminino , Reação a Corpo Estranho/patologia , Reação a Corpo Estranho/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/cirurgia , Prolapso da Valva Mitral/cirurgia , Pericardiectomia , Pericardite Constritiva/patologia , Pericardite Constritiva/cirurgia , Pericárdio/patologia , Complicações Pós-Operatórias/patologia , Complicações Pós-Operatórias/cirurgia , Reoperação
20.
J Infect Dis ; 183(6): 850-6, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11237800

RESUMO

Enterovirus 71 (EV 71) infections have high neurovirulence and fatality. Immune responses were assessed in 78 patients with EV 71 infection. EV 71 meningoencephalitis occurred more frequently in younger children and in boys. C-reactive protein levels were not elevated, although total leukocyte counts were increased in these patients. The CD40-ligand expression on T cells significantly decreased in children with meningoencephalitis (P=.041). Polymorphism of the cytotoxic T lymphocyte antigen-4 (CTLA-4) at position 49 of exon 1 showed a higher frequency of G/G genotype in patients with EV 71 meningoencephalitis than in those without meningoencephalitis (18/31 vs. 14/47; P=.045) and in control subjects (18/31 vs. 25/93l; P=.007). Specific EV 71 neutralizing antibody titers were detectable but did not differ in children with and without meningoencephalitis in the acute and convalescent stages. Results from this study suggest that younger children with a certain CTLA-4 polymorphism and altered cellular but not humoral response may be linked to EV 71 meningoencephalitis.


Assuntos
Anticorpos Antivirais/biossíntese , Infecções por Enterovirus/imunologia , Enterovirus/imunologia , Imunoconjugados , Ativação Linfocitária , Meningoencefalite/imunologia , Abatacepte , Doença Aguda , Antígenos CD , Antígenos de Diferenciação/genética , Proteína C-Reativa/biossíntese , Ligante de CD40/metabolismo , Antígeno CTLA-4 , Células Cultivadas , Quimiocina CCL5/metabolismo , Pré-Escolar , Infecções por Enterovirus/genética , Infecções por Enterovirus/virologia , Feminino , Humanos , Interferon gama/metabolismo , Interleucina-4/metabolismo , Contagem de Leucócitos , Masculino , Meningoencefalite/genética , Meningoencefalite/virologia , Polimorfismo Genético , Linfócitos T/imunologia , Taiwan
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