900 research outputs found

    The role of colloidal particles on the migration of air bubbles in porous media

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    The contamination of groundwater and soils has been a big issue of great interest and importance to human health. When organic compounds from leaking underground storage tanks or accidental spills on the surface infiltrate into the subsurface environment, they migrate downward through the unsaturated zone. These contaminants are dissolved into groundwater and move with groundwater flow. Thus, there is a need for remediation technologies. Air sparging is relatively cost-effective, as well as an efficient and safe technique for recovering organic contaminants in the subsurface. This technique introduces air into the subsurface system to enhance the volatilization and bioremediation of the contaminant in the groundwater system. In this operating system, the movement of air phase can take place either as a continuous air phase or as discrete air bubbles. However, the present research focused on continuous air phase assumption and mass balance equations of individual phases rather than taking into account the movement of air bubbles and colloidal particle capture on discrete air-water interface. Generally colloidal particles are treated as suspended particles in the water, so the hypothesis is that the rising air bubble can collect the particles and transport them up to the water table where the pump extracts the dirty bubbles from the groundwater system to the processing unit on the ground surface. This dissertation developed a pore-scale study to model the migration of discrete air phase in the presence of colloidal particles captured on the air-water interface. The model was based on the pore-scale balance equation for forces acting on a bubble rising in a porous medium in the presence of colloids. A dimensional analysis of the phenomenon was also conducted to provide a more generalized methodology to evaluate the effect of individual forces acting on an air bubble. The results indicate that the proposed model can predict the terminal velocity of a rising bubble without or with colloidal particles and provide the effect of numbers of colloidal particles, properties of colloidal particles, and solid grain size. The results showed that the terminal velocity of a discrete bubble was affected by the attachment of particles on a bubble, and then the volatile organic compound (VOC) removal rate was changed by the various radii of a bubble and the number of colloidal particles on a bubble

    Successful management of heterotopic cornual pregnancy with laparoscopic cornual resection

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    AbstractObjectiveTo examine the feasibility of laparoscopic cornual resection for the treatment of heterotopic cornual pregnancy.Study designWomen who underwent laparoscopic cornual resection for heterotopic cornual pregnancy at our hospital between January 2003 and March 2015 were retrospectively analyzed. We evaluated significant parameters such as operative complications and postoperative pregnancy outcomes of concomitant pregnancy.ResultsThirteen patients with heterotopic cornual pregnancy were included in the study. All were pregnant through assisted reproductive technology, and the diagnosis was made at a median of 6+6 weeks (range 5+4–10+0). They were successfully treated with laparoscopic cornual resection and admitted for a median of 4 days (range, 2–7) postoperatively. The median operative time was 65min (range, 35–145min) and estimated blood loss was 200mL (range, 10–3000mL). There was a spontaneous abortion at 7+6 gestational weeks in a patient who received bilateral cornual resection. Seven patients delivered babies at term and 3 at preterm. All 10 women delivered without any maternal or neonatal complications. Two were lost to follow-up.ConclusionsLaparoscopic cornual resection is a feasible primary approach for the management of heterotopic cornual pregnancy

    MitoVariome: a variome database of human mitochondrial DNA

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    Background: Mitochondrial sequence variation provides critical information for studying human evolution and variation. Mitochondrial DNA provides information on the origin of humans, and plays a substantial role in forensics, degenerative diseases, cancers, and aging process. Typically, human mitochondrial DNA has various features such as HVSI, HVSII, single-nucleotide polymorphism (SNP), restriction enzyme sites, and short tandem repeat (STR). Results: We present a variome database (MitoVariome) of human mitochondrial DNA sequences. Queries against MitoVariome can be made using accession numbers or haplogroup/continent. Query results are presented not only in text but also in HTML tables to report extensive mitochondrial sequence variation information. The variation information includes repeat pattern, restriction enzyme site polymorphism, short tandem repeat, disease information as well as single nucleotide polymorphism. It also provides a graphical interface as Gbrowse displaying all variations at a glance. The web interface also provides the tool for assigning haplogroup based on the haplogroup-diagnostic system with complete human mitochondrial SNP position list and for retrieving sequences that users query against by using accession numbers. Conclusion: MitoVariome is a freely accessible web application and database that enables human mitochondrial genome researchers to study genetic variation in mitochondrial genome with textual and graphical views accompanied by assignment function of haplogrouping if users submit their own data. Hence, the MitoVariome containing many kinds of variation features in the human mitochondrial genome will be useful for understanding mitochondrial variations of each individual, haplogroup, or geographical location to elucidate the history of human evolutionclose81

    Impact of Pneumocystis jirovecii pneumonia on kidney transplant outcome

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    Backgrounds Pneumocystis jirovecii pneumonia (PCP) remains an important cause of morbidity and mortality in kidney transplant recipients. While the acute phase toxicity in patients with PCP is well-characterized, there is a lack of data on the effects of PCP on long-term graft outcome. Method This retrospective observational study analyzed 1502 adult patients who underwent kidney transplantation at Seoul National University Hospital between 2000 and 2017. After a propensity score matching was performed, the graft and survival outcomes were compared between PCP-negative and PCP-positive groups. Results A total of 68 patients (4.5%) developed PCP after transplantation. The multivariable Cox analysis showed that positivity for cytomegalovirus and lack of initial oral antibiotic prophylaxis were risk factors of post-transplant PCP. The PCP-positive group had higher hazard ratios of graft failure [adjusted hazard ratio (HR), 3.1 (1.14–8.26); P = 0.027] and mortality [adjusted HR, 11.0 (3.68–32.80); P < 0.001] than the PCP-negative group. However, the PCP event was not related with subsequent development of de novo donor-specific antibodies or pathologic findings, such as T-cell or antibody mediated rejection and interstitial fibrosis and tubular atrophy. Conclusions PCP is a risk factor of long-term graft failure and mortality, irrespective of rejection. Accordingly, appropriate prophylaxis and treatment is needed to avoid adverse transplant outcomes of PCP.This study was supported by the Young Investigator Research Grant from the Korean Society Nephrology (Kyowa Hakko Kirin 2017) and a grant from the Basic Science Research Program through the National Research Foundation of Korea (NRF), which is funded by the Ministry of Education (NRF-2017R1D1A1B03031642). The grants had neither role in the study design, nor in data collection, analysis, interpretation and nor in manuscript writing

    Olmutinib in T790M-positive non–small cell lung cancer after failure of first-line epidermal growth factor receptor-tyrosine kinase inhibitor therapy: A global, phase 2 study

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    Receptor del factor de crecimiento epidĂ©rmico; CĂĄncer de pulmĂłn de cĂ©lulas no pequeñas; Inhibidor de la tirosina quinasaEpidermal growth factor receptor; Non-small cell lung cancer; Tyrosine kinase inhibitorReceptor del factor de creixement epidĂšrmic; CĂ ncer de pulmĂł de cĂšl·lules no petites; Inhibidor de la tirosina quinasaBackground In this open-label, international phase 2 study, the authors assessed the efficacy and safety of olmutinib in patients with locally advanced or metastatic non–small cell lung cancer (NSCLC) who had a confirmed T790M mutation and disease progression on previous epidermal growth factor receptor-tyrosine kinase inhibitor therapy. Methods Patients aged ≄20 years received once-daily oral olmutinib 800 mg continuously in 21-day cycles. The primary endpoint was the objective response rate (patients who had a confirmed best overall response of a complete or partial response), assessed by central review. Secondary endpoints included the disease control rate, the duration of objective response, progression-free survival, and overall survival. Adverse events were graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events (version 4.03). Results Overall, 162 patients (median age, 63 years; women, >60%) were enrolled from 68 sites in 9 countries. At the time of database cutoff, 23.5% of enrolled patients remained on treatment. The median treatment duration was 6.5 months (range, 0.03-21.68 months). Overall, 46.3% of patients (95% CI, 38.4%-54.3%) had a confirmed objective response (all partial responses). The best overall response (the objective response rate regardless of confirmation) was 51.9% (84 patients; 95% CI, 43.9%-59.8%). The confirmed disease control rate for all patients was 86.4% (95% CI, 80.2%-91.3%). The median duration of objective response was 12.7 months (95% CI, 8.3-15.4 months). Estimated median progression-free survival was 9.4 months (95% CI, 6.9-12.3 months), and estimated median overall survival was 19.7 months (95% CI, 15.1 months to not reached). All patients experienced treatment-emergent adverse events, and 71.6% of patients had grade ≄3 treatment-emergent adverse events. Conclusions Olmutinib has meaningful clinical activity and a manageable safety profile in patients with T790M-positive non–small cell lung cancer who received previous epidermal growth factor receptor-tyrosine kinase inhibitor therapy.Hanmi Pharmaceutical Co. Ltd

    Activation of spleen tyrosine kinase is required for TNF-α-induced endothelin-1 upregulation in human aortic endothelial cells

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    AbstractEndothelin-1 (ET-1) promotes atherosclerosis. We tested whether spleen tyrosine kinase (Syk) mediates tumor necrosis factor-α (TNF-α)-induced ET-1 upregulation in human aortic endothelial cells (HAECs) and sought to identify the signal pathways involved. TNF-α-induced reactive oxygen species (ROS) activated Syk and phosphatidylinositol 3-kinase (PI3K), which was required for the activation of AP-1 and subsequent ET-1 gene transcription. ROS mediated c-Jun NH2-terminal kinase (JNK) is also required for AP-1 activation, but Syk and PI3K regulated AP-1 activation independently of JNK. Through regulation of ET-1 production, Syk could be implicated in atherosclerosis
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