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1.
Environ Sci Technol ; 56(22): 16033-16042, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36279304

RESUMO

Recent emission measurement campaigns have improved our understanding of the total greenhouse gas (GHG) emissions across the natural gas supply chain, the individual components that contribute to these emissions, and how these emissions vary geographically. However, our current understanding of natural gas supply chain emissions does not account for the linkages between specific production basins and consumers. This work provides a detailed life cycle perspective on how GHG emissions vary according to where natural gas is produced and where it is delivered. This is accomplished by disaggregating transmission and distribution infrastructure into six regions, balancing natural gas supply and demand locations to infer the likely pathways between production and delivery, and incorporating new data on distribution meters. The average transmission distance for U.S. natural gas is 815 km but ranges from 45 to 3000 km across estimated production-to-delivery pairings. In terms of 100-year global warming potentials, the delivery of one megajoule (MJ) of natural gas to the Pacific region has the highest mean life cycle GHG emissions (13.0 g CO2e/MJ) and the delivery of natural gas to the Northeast U.S. has the lowest mean life cycle GHG emissions (8.1 g CO2e/MJ). The cradle-to-delivery scenarios developed in this work show that a national average does not adequately represent the upstream GHG emission intensity for natural gas from a specific basin or delivered to a specific consumer.


Assuntos
Gases de Efeito Estufa , Gás Natural , Animais , Gás Natural/análise , Efeito Estufa , Estágios do Ciclo de Vida
2.
Environ Sci Technol ; 56(12): 8581-8589, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35653230

RESUMO

Renewable natural gas (RNG) sources are being considered in future energy strategy discussions as potential replacements for fossil natural gas (FNG). While today's supply of RNG resources is insufficient to meet U.S. demands, there is significant interest in its viability to supplement and decarbonize the natural gas supply. However, the studies compare the life cycle global warming potential (GWP) of various RNG production pathways are lacking and focus mostly on a singular pathway. This effort is an attempt to close this gap and provide a comparison between the life cycle GWP of three major RNG pathways and the FNG pathway. The three RNG pathways evaluated are anaerobic digestion (AD), thermal gasification (TG), and power-to-gas (P2G) using various feedstocks. The functional unit is 1 MJ of compressed RNG ready for injection into the natural gas transmission network. The results show that RNG production is not always carbon neutral or negative. Depending on the pathway, the GWP impact of RNG production can range from -229 to 27 g CO2e/MJ compressed RNG, with AD of animal manure and AD of municipal solid waste being the least and the most impactful pathways, respectively, compared to the 10.1 g CO2e/MJ impact for compressed FNG.


Assuntos
Aquecimento Global , Gás Natural , Animais , Efeito Estufa , Estágios do Ciclo de Vida , Resíduos Sólidos
3.
Front Microbiol ; 14: 1240570, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38094623

RESUMO

The evidence and prevalence of multidrug-resistant (MDR) Shigella spp. poses a serious global threat to public health and the economy. Food- or water-borne MDR Shigella spp. demands an alternate strategy to counteract this threat. In this regard, phage therapy has garnered great interest from medical practitioners and researchers as a potential way to combat MDR pathogens. In this observation, we isolated Shigella phages from environmental water samples and tested against various clinically isolated MDR Shigella spp. In this study, we have defined the isolation and detailed physical and genomic characterizations of two phages Sfin-2 and Sfin-6 from environmental water samples. The phages exhibited potent lytic activity against Shigella flexneri, Shigella dysenteriae, and Shigella sonnei. They showed absorption within 5-10 min, a burst size ranging from ~74 to 265 PFU/cell, and a latent period of 5-20 min. The phages were stable at a broad pH range and survived an hour at 50°C. The purified phages Sfin-2 and Sfin-6 belong to the Siphoviridae family with an isometric head (64.90 ± 2.04 nm and 62.42 ± 4.04 nm, respectively) and a non-contractile tail (145 ± 8.5 nm and 148.47 ± 14.5 nm, respectively). The in silico analysis concluded that the size of the genomic DNA of the Sfin-2 phage is 50,390 bp with a GC content of 44.90%, while the genome size of the Sfin-6 phage is 50,523 bp with a GC content of 48.30%. A total of 85 and 83 putative open reading frames (ORFs) were predicted in the Sfin-2 and Sfin-6 phages, respectively. Furthermore, a comparative genomic and phylogenetic analysis revealed that both phages represented different isolates and novel members of the T1-like phages. Sfin-2 and Sfin-6 phages, either individually or in a cocktail form, showed a significant reduction in the viable Shigella count on raw chicken samples after 72 h of incubation. Therefore, these results indicate that these phages might have a potential role in therapeutic approaches designed for shigellosis patients as well as in the biological control of MDR Shigella spp. in the poultry or food industry during the course of meat storage.

4.
Methods Mol Biol ; 2203: 89-95, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32833206

RESUMO

Chicken kidney (CK) cells have been widely utilized in virus research studies for many years. The optimized technique of primary CK cell culture production involving both mechanical and enzymatic disaggregation is described. This updated method proved to consistently give high cell yields and resultant cultures are readily used for virus assays.


Assuntos
Técnicas de Cultura de Células/métodos , Rim/metabolismo , Cultura de Vírus/métodos , Animais , Células Cultivadas , Galinhas , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Cultura Primária de Células/métodos , Replicação Viral/fisiologia
5.
Pathol Oncol Res ; 24(2): 283-287, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28470575

RESUMO

The risk of venous thromboembolism (VTE) is increased in patients with cancer. However, the role of tumor markers as potential indicators of increased risk of VTE is still undetermined. In this retrospective observational case control study, levels of the tumor markers CEA, CA 19-9 and CA 125 in patients with colorectal, pancreatic, and ovarian cancer respectively, who were admitted to two community hospitals between January 2001 and December 2011, were compared between patients who were VTE positive and those who were VTE negative. The primary goal of this study was to determine whether VTE positive cancer patients had higher tumor marker levels compared to VTE negative cancer patients. In our study, 66.7% (48/72) of patients who were positive for VTE had elevated tumor markers while 65.3% (66/101) of patients who were negative for VTE had low (normal) tumor markers, indicating an association of high tumor marker levels with the diagnosis of VTE. This was statistically significant with an odds ratio of 3.77 and p-value of <0.0001 (95% CI of 1.99-7.14). When the VTE group was further divided into DVT and PE groups, 70.2% (40/57) of patients in the DVT positive group had high tumor markers with a p value of <0.0001 and an odds ratio of 3.99 (95% CI of 2.02 to 7.89) while 57.9% (11/19) of patients in pulmonary embolism positive group had high tumor markers; this was, however, not statistically significant (p-value of 0.35 and a CI of 0.59 to 4.10). In this retrospective study of 173 individuals with a diagnosis of either colorectal, pancreatic, or ovarian Cancer, higher tumor marker levels (CEA, CA 19-9, and CA 125 respectively) were associated with an increased risk of VTE, either DVT or PE. However, when further divided into either DVT or PE groups, the association remained statistically significant only for DVT but not for PE.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias Colorretais/complicações , Neoplasias Ovarianas/complicações , Neoplasias Pancreáticas/complicações , Tromboembolia Venosa/sangue , Adulto , Idoso , Antígeno Ca-125 , Antígeno CA-19-9/sangue , Antígeno Carcinoembrionário/sangue , Estudos de Casos e Controles , Neoplasias Colorretais/sangue , Feminino , Hospitais Comunitários , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Ovarianas/sangue , Neoplasias Pancreáticas/sangue , Estudos Retrospectivos , Fatores de Risco , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/etiologia
6.
J Exp Clin Cancer Res ; 34: 105, 2015 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-26407999

RESUMO

BACKGROUND: Arrest of metastasising lung cancer cells to the brain microvasculature maybe mediated by interactions between ligands on circulating tumour cells and endothelial E-selectin adhesion molecules; a process likely to be regulated by the endothelial glycocalyx. Using human cerebral microvascular endothelial cells and non-small cell lung cancer (NSCLC) cell lines, we describe how factors secreted by NSCLC cells i.e. cystatin C, cathepsin L, insulin-like growth factor-binding protein 7 (IGFBP7), vascular endothelial growth factor (VEGF) and tumour necrosis factor-alpha (TNF-α), damage the glycocalyx and enhance initial contacts between lung tumour and cerebral endothelial cells. METHODS: Endothelial cells were treated with tumour secreted-proteins or lung tumour conditioned medium (CM). Surface levels of E-selectin were quantified by ELISA. Adhesion of A549 and SK-MES-1 cells was examined under flow conditions (1 dyne/cm(2)). Alterations in the endothelial glycocalyx were quantified by binding of fluorescein isothiocyanate-linked wheat germ agglutinin (WGA-FITC). RESULTS: A549 and SK-MES-1 CM and secreted-proteins significantly enhanced endothelial surface E-selectin levels after 30 min and 4 h and tumour cell adhesion after 30 min, 4 and 24 h. Both coincided with significant glycocalyx degradation; A549 and SK-MES-1 CM removing 55 ± 12 % and 58 ± 18.7 % of WGA-FITC binding, respectively. Inhibition of E-selectin binding by monoclonal anti-E-selectin antibody completely attenuated tumour cell adhesion. CONCLUSION: These data suggest that metastasising lung cancer cells facilitate their own adhesion to the brain endothelium by secreting factors that damage the endothelial glycocalyx, resulting in exposure of the previously shielded adhesion molecules and engagement of the E-selectin-mediated adhesion axis.


Assuntos
Neoplasias Encefálicas/secundário , Encéfalo/irrigação sanguínea , Carcinoma Pulmonar de Células não Pequenas/patologia , Adesão Celular/fisiologia , Selectina E/metabolismo , Glicocálix/patologia , Neoplasias Pulmonares/patologia , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Catepsina L/metabolismo , Adesão Celular/efeitos dos fármacos , Moléculas de Adesão Celular/metabolismo , Linhagem Celular Transformada , Linhagem Celular Tumoral , Meios de Cultivo Condicionados/farmacologia , Cistatina C/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/patologia , Citometria de Fluxo , Humanos , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo , Pulmão/patologia , Espectrometria de Massas , Microvasos/patologia , Fator de Necrose Tumoral alfa/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
7.
N Am J Med Sci ; 6(9): 487-90, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25317397

RESUMO

CONTEXT: There are no established guidelines for the proper treatment of patients with bronchopleural fistulas (BPFs). Apart from attempts to close the fistula, emphasis of treatment and management is placed on preventive measures, early administration of antibiotics, drainage of the empyema and aggressive nutritional and rehabilitative support. CASE REPORT: A 53-year-old male presented with nausea, vomiting, and dry cough with eventual respiratory failure. He was found to have an empyema of the left hemithorax which was managed with thoracostomy drainage and antibiotics. However, he had persistent air leak through the chest tube due to a BPF. Bronchoscopy failed to localize the involved segment. Application of fibrin glue through the chest tube succeeded in completely sealing the leak. CONCLUSION: To our knowledge, this is the first case report in which fibrin glue was successfully used intrapleurally to close a BPF related to an empyema.

8.
Transl Oncol ; 6(6): 703-14, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24466373

RESUMO

Epithelial ovarian cancer (EOC) metastasizes transcoelomically to the peritoneum and omentum, and despite surgery and chemotherapy, recurrent disease is likely. Metastasis requires the induction of proangiogenic changes in the omental microenvironment and EOC-induced omental angiogenesis is currently a key therapeutic target. In particular, antiangiogenic therapies targeting the vascular endothelial growth factor A (VEGFA) pathway are commonly used, although, with limited effects. Here, using human omental microvascular endothelial cells (HOMECs) and ovarian cancer cell lines as an in vitro model, we show that factors secreted from EOC cells increased proliferation, migration, and tube-like structure formation in HOMECs. However, EOC-induced angiogenic tube-like formation and migration were unaffected by inhibition of tyrosine kinase activity of VEGF receptors 1 and 2 (Semaxanib; SU5416) or neutralization of VEGFA (neutralizing anti-VEGFA antibody), although VEGFA165-induced HOMEC migration and tube-like structure formation were abolished. Proteomic investigation of the EOC secretome identified several alternative angiogenesis-related proteins. We screened these for their ability to induce an angiogenic phenotype in HOMECs, i.e., proliferation, migration, and tube-like structure formation. Hepatocyte growth factor (HGF) and insulin-like growth factor binding protein 7 (IGFBP-7) increased all three parameters, and cathepsin L (CL) increased migration and tubule formation. Further investigation confirmed expression of the HGF receptor c-Met in HOMECs. HGF- and EOC-induced proliferation and angiogenic tube structure formation were blocked by the c-Met inhibitor PF04217903. Our results highlight key alternative angiogenic mediators for metastatic EOC, namely, HGF, CL, and IGFBP-7, suggesting that effective antiangiogenic therapeutic strategies for this disease require inhibition of multiple angiogenic pathways.

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