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1.
Nature ; 621(7977): 66-70, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37558882

RESUMO

The characteristic excitation of a metal is its plasmon, which is a quantized collective oscillation of its electron density. In 1956, David Pines predicted that a distinct type of plasmon, dubbed a 'demon', could exist in three-dimensional (3D) metals containing more than one species of charge carrier1. Consisting of out-of-phase movement of electrons in different bands, demons are acoustic, electrically neutral and do not couple to light, so have never been detected in an equilibrium, 3D metal. Nevertheless, demons are believed to be critical for diverse phenomena including phase transitions in mixed-valence semimetals2, optical properties of metal nanoparticles3, soundarons in Weyl semimetals4 and high-temperature superconductivity in, for example, metal hydrides3,5-7. Here, we present evidence for a demon in Sr2RuO4 from momentum-resolved electron energy-loss spectroscopy. Formed of electrons in the ß and γ bands, the demon is gapless with critical momentum qc = 0.08 reciprocal lattice units and room-temperature velocity v = (1.065 ± 0.12) × 105 m s-1 that undergoes a 31% renormalization upon cooling to 30 K because of coupling to the particle-hole continuum. The momentum dependence of the intensity of the demon confirms its neutral character. Our study confirms a 67-year old prediction and indicates that demons may be a pervasive feature of multiband metals.

2.
Proc Natl Acad Sci U S A ; 121(4): e2317283121, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38227666

RESUMO

Despite many clinical trials, CAR-T cells are not yet approved for human solid tumor therapy. One popular target is mesothelin (MSLN) which is highly expressed on the surface of about 30% of cancers including mesothelioma and cancers of the ovary, pancreas, and lung. MSLN is shed by proteases that cleave near the C terminus, leaving a short peptide attached to the cell. Most anti-MSLN antibodies bind to shed MSLN, which can prevent their binding to target cells. To overcome this limitation, we developed an antibody (15B6) that binds next to the membrane at the protease-sensitive region, does not bind to shed MSLN, and makes CAR-T cells that have much higher anti-tumor activity than a CAR-T that binds to shed MSLN. We have now humanized the Fv (h15B6), so the CAR-T can be used to treat patients and show that h15B6 CAR-T produces complete regressions in a hard-to-treat pancreatic cancer patient derived xenograft model, whereas CAR-T targeting a shed epitope (SS1) have no anti-tumor activity. In these pancreatic cancers, the h15B6 CAR-T replicates and replaces the cancer cells, whereas there are no CAR-T cells in the tumors receiving SS1 CAR-T. To determine the mechanism accounting for high activity, we used an OVCAR-8 intraperitoneal model to show that poorly active SS1-CAR-T cells are bound to shed MSLN, whereas highly active h15B6 CAR-T do not contain bound MSLN enabling them to bind to and kill cancer cells.


Assuntos
Neoplasias Pancreáticas , Receptores de Antígenos Quiméricos , Feminino , Humanos , Linhagem Celular Tumoral , Proteínas Ligadas por GPI/metabolismo , Mesotelina , Neoplasias Pancreáticas/tratamento farmacológico , Linfócitos T/metabolismo
3.
Phys Rev Lett ; 130(22): 226503, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37327438

RESUMO

Disorder and electron-electron interaction play essential roles in the physics of electron systems in condensed matter. In two-dimensional, quantum Hall systems, extensive studies of disorder-induced localization have led to the emergence of a scaling picture with a single extended state, characterized by a power-law divergence of the localization length in the zero-temperature limit. Experimentally, scaling has been investigated via measuring the temperature dependence of plateau-to-plateau transitions between the integer quantum Hall states (IQHSs), yielding a critical exponent κ≃0.42. Here we report scaling measurements in the fractional quantum Hall state (FQHS) regime where interaction plays a dominant role. Our Letter is partly motivated by recent calculations, based on the composite fermion theory, that suggest identical critical exponents in both IQHS and FQHS cases to the extent that the interaction between composite fermions is negligible. The samples used in our experiments are two-dimensional electron systems confined to GaAs quantum wells of exceptionally high quality. We find that κ varies for transitions between different FQHSs observed on the flanks of Landau level filling factor ν=1/2 and has a value close to that reported for the IQHS transitions only for a limited number of transitions between high-order FQHSs with intermediate strength. We discuss possible origins of the nonuniversal κ observed in our experiments.


Assuntos
Elétrons , Física , Temperatura
4.
Malays J Pathol ; 45(2): 215-227, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37658531

RESUMO

INTRODUCTION: Acute respiratory infection (ARI) contributes to significant mortality and morbidity worldwide and is usually caused by a wide range of respiratory pathogens. This study aims to describe the performance of QIAstat-Dx® Respiratory Panel V2 (RP) and RespiFinder® 2SMART assays for respiratory pathogens detection. MATERIALS AND METHODS: A total of 110 nasopharyngeal swabs (NPS) were collected from children aged one month to 12 years old who were admitted with ARI in UKMMC during a one-year period. The two qPCR assays were conducted in parallel. RESULTS: Ninety-seven samples (88.2%) were positive by QIAstat-Dx RP and 86 (78.2%) by RespiFinder assay. The overall agreement on both assays was substantial (kappa value: 0.769) with excellent concordance rate of 96.95%. Using both assays, hRV/EV, INF A/H1N1 and RSV were the most common pathogens detected. Influenza A/H1N1 infection was significantly seen higher in older children (age group > 60 months old) (53.3%, p-value < 0.05). Meanwhile, RSV and hRV/EV infection were seen among below one-year-old children. Co-infections by two to four pathogens were detected in 17 (17.5%) samples by QIAstat-Dx RP and 12 (14%) samples by RespiFinder, mainly involving hRV/EV. Bacterial detection was observed only in 5 (4.5%) and 6 (5.4%) samples by QIAstat-Dx RP and RespiFinder, respectively, with Mycoplasma pneumoniae the most common detected. CONCLUSION: The overall performance of the two qPCR assays was comparable and showed excellent agreement. Both detected various clinically important respiratory pathogens in a single test with simultaneous multiple infection detection. The use of qPCR as a routine diagnostic test can improve diagnosis and management.


Assuntos
Coinfecção , Vírus da Influenza A Subtipo H1N1 , Infecções Respiratórias , Criança , Humanos , Pré-Escolar , Lactente , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Infecções Respiratórias/diagnóstico , Hospitalização
5.
Eur Cell Mater ; 43: 252-266, 2022 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-35652679

RESUMO

Polyethylene terephthalate (PET) artificial ligaments offer an unlimited source of ligaments without donor-site-related morbidity and with good mechanical properties for a rapid return to sporting activities. Developing PET artificial ligaments with excellent ligamentisation and ligament-bone healing is still a considerable challenge. This study aimed to investigate the effects of the profiled PET/collagen/calcium phosphate (PET/C/CaP) ligament upon cell growth, ligamentisation and ligament-bone healing in vitro and in vivo. Profiled PET/C/CaP filaments were made by melt-spinning process with 2 % CaP hybrid spinning and collagen coating. Rat mesenchymal stem cells (MSCs) were cultured on the profiled PET/C filaments for cytotoxicity, viability, scanning electron microscopy (SEM) and ligament-related gene expression analysis. MSCs' osteogenic capacity on the profiled PET/CaP filaments was identified by detecting osteogenic gene expression and alizarin red S staining. For in vivo verification, an animal study was performed to evaluate the effect of the profiled PET/C/CaP ligament in a rabbit knee medial collateral ligament reinforcement reconstruction model. The graft ligamentisation and bone formation were investigated by SEM, histology, microcomputed tomography and mechanical tests. The profiled PET/C filaments enhanced MSC proliferation and ligament-related gene expression. Furthermore, they enhanced osteogenic gene expression, alkaline phosphatase activity and mineralisation of MSCs. The in vivo study indicated that the profiled PET/C/CaP ligament enhanced ligamentous matrix remodelling and bone formation. Therefore, their use is an effective strategy for promoting MSCs' ligamentous and osteogenic potential in vitro and enhancing ligamentous matrix remodelling and bone formation in vivo.


Assuntos
Osteogênese , Polietilenotereftalatos , Animais , Fosfatos de Cálcio/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Colágeno/metabolismo , Colágeno/farmacologia , Polietilenotereftalatos/farmacologia , Coelhos , Ratos , Microtomografia por Raio-X
6.
Tech Coloproctol ; 25(3): 267-278, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33386511

RESUMO

BACKGROUND: Diabetes mellitus has been commonly associated with poor surgical outcomes. The aim of this meta-analysis was to assess the impact of diabetes on postoperative complications following colorectal surgery. METHODS: Medline, Embase and China National Knowledge Infrastructure electronic databases were reviewed from inception until May 9th 2020. Meta-analysis of proportions and comparative meta-analysis were conducted. Studies that involved patients with diabetes mellitus having colorectal surgery, with the inclusion of patients without a history of diabetes as a control, were selected. The outcomes measured were postoperative complications. RESULTS: Fifty-five studies with a total of 666,886 patients comprising 93,173 patients with diabetes and 573,713 patients without diabetes were included. Anastomotic leak (OR 2.407; 95% CI 1.837-3.155; p < 0.001), surgical site infections (OR 1.979; 95% CI 1.636-2.394; p < 0.001), urinary complications (OR 1.687; 95% CI 1.210-2.353; p = 0.002), and hospital readmissions (OR 1.406; 95% CI 1.349-1.466; p < 0.001) were found to be significantly higher amongst patients with diabetes following colorectal surgery. The incidence of septicemia, intra-abdominal infections, mechanical failure of wound healing comprising wound dehiscence and disruption, pulmonary complications, reoperation, and 30-day mortality were not significantly increased. CONCLUSIONS: This meta-analysis and systematic review found a higher incidence of postoperative complications including anastomotic leaks and a higher re-admission rate. Risk profiling for diabetes prior to surgery and perioperative optimization for patients with diabetes is critical to improve surgical outcomes.


Assuntos
Cirurgia Colorretal , Diabetes Mellitus , Procedimentos Cirúrgicos do Sistema Digestório , Fístula Anastomótica/epidemiologia , Fístula Anastomótica/etiologia , Diabetes Mellitus/epidemiologia , Humanos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia
7.
Tech Coloproctol ; 25(1): 35-48, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32851500

RESUMO

BACKGROUND: Studies have shown differences in postoperative outcomes between two minimally invasive extraction methods for colorectal lesions-natural orifice specimen extraction surgery (NOSES) and conventional laparoscopic surgery (CLS). The aim of this study was to discover the major differences in NOSES and CLS to refine current practice. METHODS: Electronic databases were searched for articles comparing NOSES and CLS from inception till March 2020. Weighted mean differences (WMD) and odds ratio (OR) were estimated for continuous and dichotomous outcomes, respectively. Summary statistics were calculated using the DerSimonian and Laird random effects. RESULTS: Twenty-one studies (15 on malignant disease, 4 on benign disease, 2 on both) were included in this meta-analysis, totalling 2378 patients (1079 NOSE, 1299 CLS). NOSE was associated with decreased: intraoperative bleeding (WMD: - 10.652 ml; 95% CI: - 18.818 ml to - 2.482 ml; p < 0.001), pain score (WMD: - 1.520; 95% CI - 1.965 to - 1.076; p < 0.001), time to flatus (WMD: - 0.306 days; 95% CI: - 0.526 to - 0.085 days; p < 0.001), length of hospital stay (WMD: - 1.048 days; 95% CI: - 1.488 to - 0.609 days; p < 0.001), and total morbidity (OR: 0.548; 95% CI: 0.387 to 0.777; p = 0.001). Subgroup analyses showed significant differences between malignant and benign lesions for intraoperative bleeding (p = 0.011) and pain score (p = 0.010). Meta-regression analyses showed an association between the American Society of Anaesthesiologists (ASA) physical status classification III with pain (p = 0.03) and ASA III with time to flatus (p = 0.04). CONCLUSIONS: This meta-analysis and meta-regression demonstrated that NOSES had better postoperative outcomes compared to CLS. More comprehensive reviews should be conducted on the long-term outcomes specific to the extraction site to better inform clinical practice.


Assuntos
Neoplasias Colorretais , Procedimentos Cirúrgicos do Sistema Digestório , Laparoscopia , Neoplasias Colorretais/cirurgia , Humanos , Tempo de Internação , Resultado do Tratamento
8.
Mol Biol Evol ; 34(4): 903-907, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28087780

RESUMO

Focal copy number gains or losses are important genomic hallmarks of cancer. The genomic distribution of oncogenes and tumor-suppressor genes (TSG) in relation to focal copy number aberrations is unclear. Our analysis revealed that the mean distance of TSGs from oncogenes was significantly shorter than that of noncancer genes, suggesting that oncogenes and TSGs tend to be in close physical proximity in the human genome. Such relationship was conserved in mouse and drosophila. Pan-cancer analysis using data from The Cancer Genome Atlas indicated that oncogenes without a nearby TSG are more prone to amplification. In conclusion, our study provides evidence for the nonrandom distribution of oncogenes and TSGs across different species. Our data also support that the existence of a neighboring TSG can suppress amplification of an oncogene, shedding new light on a previously unappreciated protective mechanism of TSGs.


Assuntos
Amplificação de Genes/genética , Genes Supressores de Tumor/fisiologia , Oncogenes/genética , Animais , Bases de Dados de Ácidos Nucleicos , Dosagem de Genes , Regulação Neoplásica da Expressão Gênica/genética , Genômica , Humanos , Mutação , Neoplasias/genética
9.
Insect Mol Biol ; 27(4): 512-521, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29693770

RESUMO

Apis mellifera plays crucial roles in maintaining the balance of global ecosystems and stability of agricultural systems by helping pollination of flowering plants, including many crops. In recent years, this balance has been disrupted greatly by some pesticides, which results in great losses of honeybees worldwide. Previous studies have found that pesticide-caused memory loss might be one of the major reasons for colony loss. Histone deacetylase inhibitors (HDACis) are chemical compounds that inhibit the activity of histone deacetylases and are known to cause hyperacetylation of histone cores and influence gene expression. In our study, the HDACi sodium butyrate was applied to honeybees as a dietary supplement. The effect of sodium butyrate on the expression profiles of memory-related genes was analysed by quantitative reverse transcription PCR. The results revealed that this HDACi had up-regulation effects on most of the memory-related genes in bees, even in bees treated with imidacloprid. In addition, using the proboscis extension reflex to evaluate olfactory learning in bees, we found that this HDACi boosted the memory formation of bees after impairment owing to imidacloprid exposure. This study investigated the association between gene expression and memory formation from an epigenetic perspective. Additionally, we further demonstrate the possibility of enhancing bee learning using HDACis and provide initial data for future research.


Assuntos
Abelhas/fisiologia , Ácido Butírico/farmacologia , Expressão Gênica , Antagonistas dos Receptores Histamínicos/farmacologia , Inibidores de Histona Desacetilases/metabolismo , Proteínas de Insetos/genética , Memória , Acetilação , Animais , Abelhas/enzimologia , Abelhas/genética , Proteínas de Insetos/metabolismo , Inseticidas/toxicidade , Aprendizagem , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade
10.
Eur J Cancer Care (Engl) ; 27(2): e12696, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28440587

RESUMO

Helping breast cancer patients who desire a pregnancy after cancer treatment is a vital issue. Little is known about the complex context of the decision to become pregnant after breast cancer treatment. The purpose of this study was to understand the risk-benefit perception of choosing conception or contraception after treatment in Taiwan. We applied grounded theory to guide this exploratory qualitative study. Data were collected through in-depth interviews with 16 breast cancer patients. Pregnancy was addressed in the context of cancer as a potentially life-threatening diagnosis and its treatment. The verbatim transcriptions were analysed using constant comparative analysis and methods of open, axial and selective coding. The core theme that described the risk perception of pregnancy among patients with breast cancer after treatment focused on "reaching the balance of life." Seven dimensions of risk-benefit perception of pregnancy, including perceived health status, safety, expected gain, harm, loading, support and time were explored among women treated for breast cancer. We found that women treated for breast cancer applied risk-benefit perceptions to decide whether to become pregnant. Implementing contextual counselling could help to decrease perceived barriers to choose pregnancy and increase the quality of pregnancy care.


Assuntos
Neoplasias da Mama/psicologia , Saúde Reprodutiva , Medição de Risco , Sobreviventes , Adulto , Tomada de Decisões , Feminino , Teoria Fundamentada , Nível de Saúde , Humanos , Pessoa de Meia-Idade , Pesquisa Qualitativa , Taiwan , Adulto Jovem
11.
Crit Rev Clin Lab Sci ; 54(6): 433-445, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28990451

RESUMO

In recent years, the abuse of opioid drugs has resulted in greater prevalence of addiction, overdose, and deaths attributable to opioid abuse. The epidemic of opioid abuse has prompted professional and government agencies to issue practice guidelines for prescribing opioids to manage chronic pain. An important tool available to providers is the drug test for use in the initial assessment of patients for possible opioid therapy, subsequent monitoring of compliance, and documentation of suspected aberrant drug behaviors. This review discusses the issues that most affect the clinical utility of drug testing in chronic pain management with opioid therapy. It focuses on the two most commonly used specimen matrices in drug testing: urine and oral fluid. The advantages and disadvantages of urine and oral fluid in the entire testing process, from specimen collection and analytical methodologies to result interpretation are reviewed. The analytical sensitivity and specificity limitations of immunoassays used for testing are examined in detail to draw attention to how these shortcomings can affect result interpretation and influence clinical decision-making in pain management. The need for specific identification and quantitative measurement of the drugs and metabolites present to investigate suspected aberrant drug behavior or unexpected positive results is analyzed. Also presented are recent developments in optimization of test menus and testing strategies, such as the modification of the standard screen and reflexed-confirmation testing model by eliminating some of the initial immunoassay-based tests and proceeding directly to definitive testing by mass spectrometry assays.


Assuntos
Analgésicos Opioides , Testes de Química Clínica/métodos , Monitoramento de Medicamentos/métodos , Manejo da Dor/métodos , Analgésicos Opioides/análise , Analgésicos Opioides/uso terapêutico , Analgésicos Opioides/urina , Humanos , Imunoensaio , Programas de Rastreamento , Transtornos Relacionados ao Uso de Opioides/diagnóstico , Transtornos Relacionados ao Uso de Opioides/urina , Saliva/química , Detecção do Abuso de Substâncias
12.
J Zoo Wildl Med ; 48(1): 144-151, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28363045

RESUMO

Serum 25-hydroxyvitamin D concentrations were assessed in subadult to adult captive lowland gorillas ( Gorilla gorilla gorilla) (n = 26) at two institutions with different husbandry and management practices. Serum 25-hydroxyvitamin D (25[OH]D) concentrations for gorillas managed predominantly indoors was low (14.2 ± 5.9 ng/ml), despite consuming commercial biscuits fortified with vitamin D3. Concentrations of 25(OH)D in gorillas with near daily outdoor access were significantly higher than gorillas managed indoors, although many individuals still had serum values below concentrations recommended for adult humans. Consideration should be given to assessing 25(OH)D concentrations in all captive gorillas and providing specific supplementation, particularly to juveniles without access to direct sunlight.


Assuntos
Gorilla gorilla/sangue , Vitamina D/análogos & derivados , Animais , Animais de Zoológico , Feminino , Abrigo para Animais , Masculino , Vitamina D/sangue
13.
Int J Mol Sci ; 17(4)2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27110769

RESUMO

Regarding breast cancer treatment, triple negative breast cancer (TNBC) is a difficult issue. Most TNBC patients die of cancer metastasis. Thus, to develop a new regimen to attenuate TNBC metastatic potential is urgently needed. MART-10 (19-nor-2α-(3-hydroxypropyl)-1α,25(OH)2D3), the newly-synthesized 1α,25(OH)2D3 analog, has been shown to be much more potent in cancer growth inhibition than 1α,25(OH)2D3 and be active in vivo without inducing obvious side effect. In this study, we demonstrated that both 1α,25(OH)2D3 and MART-10 could effectively repress TNBC cells migration and invasion with MART-10 more effective. MART-10 and 1α,25(OH)2D3 induced cadherin switching (upregulation of E-cadherin and downregulation of N-cadherin) and downregulated P-cadherin expression in MDA-MB-231 cells. The EMT(epithelial mesenchymal transition) process in MDA-MB-231 cells was repressed by MART-10 through inhibiting Zeb1, Zeb2, Slug, and Twist expression. LCN2, one kind of breast cancer metastasis stimulator, was also found for the first time to be repressed by 1α,25(OH)2D3 and MART-10 in breast cancer cells. Matrix metalloproteinase-9 (MMP-9) activity was also downregulated by MART-10. Furthermore, F-actin synthesis in MDA-MB-231 cells was attenuated as exposure to 1α,25(OH)2D3 and MART-10. Based on our result, we conclude that MART-10 could effectively inhibit TNBC cells metastatic potential and deserves further investigation as a new regimen to treat TNBC.


Assuntos
Movimento Celular/efeitos dos fármacos , Colecalciferol/análogos & derivados , Neoplasias de Mama Triplo Negativas/patologia , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Colecalciferol/farmacologia , Colecalciferol/uso terapêutico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Invasividade Neoplásica , Metástase Neoplásica/prevenção & controle , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
14.
Int J Mol Sci ; 17(8)2016 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-27529229

RESUMO

Cholangiocarcinoma (CCA) is a devastating disease without effective treatments. 1α,25(OH)2D3, the active form of Vitamin D, has emerged as a new anti-cancer regimen. However, the side effect of hypercalcemia impedes its systemic administration. 25(OH)D is biologically inert and needs hydroxylation by CYP27B1 to form 1α,25(OH)2D3, which is originally believed to only take place in kidneys. Recently, the extra-renal expression of CYP27B1 has been identified and in vitro conversion of 25(OH)D to 1α,25(OH)2D3 has been found in some cancer cells with CYP27B1 expression. In this study, CYP27B1 expression was demonstrated in CCA cells and human CCA specimens. 25(OH)D effectively represses SNU308 cells growth, which was strengthened or attenuated as CYP27B1 overexpression or knockdown. Lipocalcin-2 (LCN2) was also found to be repressed by 25(OH)D. After treatment with 800 ng/mL 25(OH)D, the intracellular 1α,25(OH)2D3 concentration was higher in SNU308 cells with CYP27B1 overexpression than wild type SNU308 cells. In a xenograft animal experiment, 25(OH)D, at a dose of 6 µg/kg or 20 µg/kg, significantly inhibited SNU308 cells' growth without inducing obvious side effects. Collectively, our results indicated that SNU308 cells were able to convert 25(OH)D to 1α,25(OH)2D3 and 25(OH)D CYP27B1 gene therapy could be deemed as a promising therapeutic direction for CCA.


Assuntos
Calcitriol/metabolismo , Proliferação de Células/efeitos dos fármacos , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/metabolismo , Vitamina D/análogos & derivados , 25-Hidroxivitamina D3 1-alfa-Hidroxilase/metabolismo , Animais , Linhagem Celular Tumoral , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Vitamina D/metabolismo , Vitamina D/farmacologia , Vitamina D/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Gene Ther ; 22(2): 155-62, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25354682

RESUMO

Replicating virus vectors are attractive tools for anticancer gene therapy, but the potential for adverse events due to uncontrolled spread of the vectors has been a major concern. To design a tumor-specific retroviral replicating vector (RRV), we replaced the U3 region of the RRV ACE-GFP with a regulatory sequence consisting of the hepatitis B virus enhancer II (EII) and human α-fetoprotein (AFP) core promoter to produce ACE-GFP-EIIAFP, a hepatocellular carcinoma (HCC)-targeting RRV. Similar to ACE-GFP, ACE-GFP-EIIAFP exhibited robust green fluorescent protein (GFP) expression in HCC cells and, most importantly, it exhibited HCC-specific replication and did not replicate in non-HCC tumor cells or normal liver cells. We sequenced the promoter region of ACE-GFP-EIIAFP collected from serial infection cycles to examine the genomic stability of the vector during its replicative spread, and found that the vector could retain the hybrid promoter in the genome for at least six infection cycles. In vitro studies revealed that ACE-CD-EIIAFP and ACE-PNP-EIIAFP, which express the yeast cytosine deaminase and Escherichia coli purine nucleoside phosphorylase, respectively, exert a highly potent cytotoxic effect on HCC cells in the presence of their respective prodrugs. In vivo, ACE-CD-EIIAFP-mediated suicide gene therapy efficiently suppressed HCC tumor growth and no detectable RRV signal was observed in extratumoral tissues. These results suggest that the tumor-specific, suicide-gene-encoding RRV may fulfill the promise of retroviral gene therapy for cancer.


Assuntos
Carcinoma Hepatocelular/terapia , Vírus da Leucemia Murina/genética , Neoplasias Hepáticas Experimentais/terapia , Animais , Sequência de Bases , Carcinoma Hepatocelular/genética , Terapia Genética , Vetores Genéticos , Instabilidade Genômica , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Células HEK293 , Células Hep G2 , Humanos , Neoplasias Hepáticas Experimentais/genética , Células MCF-7 , Camundongos Endogâmicos BALB C , Camundongos Nus , Dados de Sequência Molecular , Transplante de Neoplasias , Regiões Promotoras Genéticas , Sequências Repetidas Terminais , Transcrição Gênica , Replicação Viral , alfa-Fetoproteínas/genética , alfa-Fetoproteínas/metabolismo
16.
MMWR Morb Mortal Wkly Rep ; 64(28): 763-6, 2015 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-26203630

RESUMO

On March 22, 2015, the Agency for Toxic Substances and Disease Registry (ATSDR) was notified by the U.S. Environmental Protection Agency (EPA) of four cases of suspected acute methyl bromide toxicity among family members vacationing at a condominium resort in the U.S. Virgin Islands. Methyl bromide is a pesticide that has been banned in the United States for use in homes and other residential settings. An investigation conducted by the U.S. Virgin Islands Department of Health (VIDOH), the U.S. Virgin Islands Department of Planning and Natural Resources (DPNR), and EPA confirmed that methyl bromide had been used as a fumigant on March 18 in the building where the family had been residing, 2 days before they were transported to the hospital; three family members had life-threatening illness. On March 25, 2015, a stop-use order for methyl bromide was issued by DPNR to the pest control company that had performed the fumigation. Subsequent investigation revealed that previous fumigation with methyl bromide had occurred on October 20, 2014, at the same condominium resort. In addition to the four ill family members, 37 persons who might have been exposed to methyl bromide as a result of the October 2014 or March 2015 fumigations were identified by VIDOH and ATSDR. Standardized health questionnaires were administered to 16 of the 20 persons for whom contact information was available; six of 16 had symptoms consistent with methyl bromide exposure, including headache and fatigue. Pest control companies should be aware that use of methyl bromide is banned in homes and other residential settings, and clinicians should be aware of the toxicologic syndrome that exposure to methyl bromide can cause.


Assuntos
Exposição Ambiental/efeitos adversos , Fumigação/efeitos adversos , Habitação , Hidrocarbonetos Bromados/toxicidade , Índice de Gravidade de Doença , Adolescente , Adulto , Análise por Conglomerados , Feminino , Fumigação/legislação & jurisprudência , Humanos , Masculino , Pessoa de Meia-Idade , Ilhas Virgens Americanas , Adulto Jovem
17.
Biometals ; 28(6): 987-96, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26420239

RESUMO

A coordinated network of zinc transporters and binding proteins tightly regulate cellular zinc levels. Canonical responses to zinc availability are thought to be mediated by changes in gene expression of key zinc transporters. We investigated the temporal relationships of actual zinc uptake with patterns of gene expression in membrane-bound zinc transporters in the human immortalized T lymphocyte Jurkat cell line. Cellular zinc levels were elevated or reduced with exogenous zinc sulfate or N,N,N',N-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN), respectively. Excess zinc resulted in a rapid 44 % decrease in the rate of zinc uptake within 10 min. After 120 min, the expression of metallothionein (positive control) increased, as well as the zinc exporter, ZnT1; however, the expression of zinc importers did not change during this time period. Zinc chelation with TPEN resulted in a rapid twofold increase in the rate of zinc uptake within 10 min. After 120 min, the expression of ZnT1 decreased, while again the expression of zinc importers did not change. Overall, zinc transporter gene expression kinetics did not match actual changes in cellular zinc uptake with exogenous zinc or TPEN treatments. This suggests zinc transporter regulation may be the initial response to changes in zinc within Jurkat cells.


Assuntos
Proteínas de Transporte de Cátions/genética , Metalotioneína/genética , Sulfato de Zinco/farmacologia , Zinco/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Cátions Bivalentes , Quelantes/farmacologia , Relação Dose-Resposta a Droga , Etilaminas/farmacologia , Regulação da Expressão Gênica , Humanos , Transporte de Íons , Células Jurkat , Metalotioneína/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Piridinas/farmacologia
18.
Pain Med ; 16(6): 1132-6, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25800409

RESUMO

OBJECTIVE: To determine whether the prevailing liquid chromatography and tandem mass spectroscopy assay (LC-MS/MS) assay designed to monitor buprenorphine compliance of the sublingual formulation used in the substance abuse treatment setting can be extrapolated to the transdermal formulation used in the chronic pain treatment setting, which is 1000-fold less concentrated. DESIGN: Retrospective chart review. SUBJECTS: Self-reported compliant patients using the transdermal or sublingual formulations of buprenorhphine. Transdermal patch application was also visually confirmed during clinic visits. METHODS: Urine drug test results from a LC-MS/MS were compared between samples from transdermal and sublingual patients. RESULTS: While all sublingual patients tested positive for at least one metabolite of buprenorphine, only 69% of the transdermal patients did so. In addition, the most abundant metabolite in the transdermal patients was buprenorphine-glucuronide, as compared with norbuprenorphine-glucuronide in sublingual patients. CONCLUSIONS: These data suggest that currently available urine drug tests for buprenorphine, including the more expensive LC-MS/MS based assays, may not be sufficiently sensitive to detect the metabolites from transdermal buprenorphine patients. This study highlights the need to evaluate the value and sensitivity of urine drug tests given the wide range of buprenorphine dosing in clinical practice. These results underscore the need for additional cost benefit analyses comparing different confirmatory drug testing techniques including many commercially available drug testing options. © 2014 Wiley Periodicals, Inc.


Assuntos
Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/urina , Buprenorfina/administração & dosagem , Buprenorfina/urina , Dor Crônica/urina , Administração Cutânea , Administração Sublingual , Adulto , Cromatografia Líquida/normas , Dor Crônica/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Detecção do Abuso de Substâncias/normas , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Transtornos Relacionados ao Uso de Substâncias/urina , Espectrometria de Massas em Tandem/normas , Resultado do Tratamento , Urinálise/normas
19.
Can J Physiol Pharmacol ; 93(5): 333-48, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25918960

RESUMO

The active form of vitamin D3, 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3 or calcitriol), is known to inhibit the proliferation and invasiveness of many types of cancer cells, including breast, colon, pancreatic, prostate, and liver cancer cells. These findings support the use of 1α,25(OH)2D3 for the treatment of these types of cancer. However, 1α,25(OH)2D3 can cause hypercalcemia, so analogs of 1α,25(OH)2D3 that are less calcemic but exhibit more potent anti-tumor activity would be good candidates as therapeutic agents. Therefore, a series of 19-norvitamin D analogs, in which the methylidene group on C19 is replaced with 2 hydrogen atoms, have been synthesized by several laboratories. In our laboratory, we have designed and synthesized a series of 2α-functional group substituted 19-norvitamin D3 analogs and examined their anti-proliferative activity. Among them, 2α- and 2ß-(3-hydroxypropyl)-1α,25-dihydroxy-19-norvitamin D3 (MART-10 and MART-11) were found to be the most promising. Here, we review the rationale and approaches for the synthesis of different 19-norvitamin D analogs, and the pre-clinical studies using these analogs in breast cancer cells, in particular, we chose MART-10 for its potential application to the prevention and treatment of breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Colecalciferol/análogos & derivados , Animais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Colecalciferol/síntese química , Colecalciferol/metabolismo , Colecalciferol/uso terapêutico , Feminino , Humanos , Receptores de Calcitriol/metabolismo
20.
Asian-Australas J Anim Sci ; 28(5): 605-11, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25715691

RESUMO

A synthetic strain of ducks (Anas platyrhynchos) was developed by introducing genes for long duration of fertility to be used as mother of mule ducklings and a seven-generation selection experiment was conducted to increase the number of fertile eggs after a single artificial insemination (AI) with pooled Muscovy semen. Reciprocal crossbreeding between Brown Tsaiya LRI-2 (with long duration of fertility) and Pekin L-201 (with white plumage mule ducklings) ducks produced the G0. Then G1 were intercrossed to produce G2 and so on for the following generations. Each female duck was inseminated 3 times, at 26, 29, and 32 weeks of age. The eggs were collected for 14 days from day 2 after AI. Individual data regarding the number of incubated eggs (Ie), the number of fertile eggs at candling at day 7 of incubation (F), the total number of dead embryos (M), the maximum duration of fertility (Dm) and the number of hatched mule ducklings (H) with plumage colour were recorded. The selection criterion was the breeding values of the best linear unbiased prediction animal model for F. The results show high percentage of exhibited heterosis in G2 for traits to improve (19.1% for F and 12.9% for H); F with a value of 5.92 (vs 3.74 in the Pekin L-201) was improved in the G2. Heritabilities were found to be low for Ie (h (2) = 0.07±0.03) and M (h (2) = 0.07±0.01), moderately low for Dm (h (2) = 0.13±0.02), of medium values for H (h (2) = 0.20±0.03) and F (h (2) = 0.23±0.03). High and favourable genetic correlations existed between F and Dm (rg = 0.93), between F and H (rg = 0.97) and between Dm and H (rg = 0.90). The selection experiment showed a positive trend for phenotypic values of F (6.38 fertile eggs in G10 of synthetic strain vs 5.59 eggs in G4, and 3.74 eggs in Pekin L-201), with correlated response for increasing H (5.73 ducklings in G10 vs 4.86 in G4, and 3.09 ducklings in Pekin L-201) and maximum duration of the fertile period without increasing the embryo mortality rate. The average predicted genetic response for F was 40% of genetic standard deviation per generation of selection. The mule ducklings' feather colour also was improved. It was concluded that this study provided results for a better understanding of the genetics of the duration of fertility traits in the common female duck bred for mule and that the selection of a synthetic strain was effective method of improvement.

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