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排序方式: 共有814条查询结果,搜索用时 15 毫秒
1.
Valentina Isetta Josep M. Montserrat Raquel Santano Alison J. Wimms Dinesh Ramanan Holger Woehrle Daniel Navajas Ramon Farré 《PloS one》2016,11(3)
Bench testing is a useful method to characterize the response of different automatic positive airway pressure (APAP) devices under well-controlled conditions. However, previous models did not consider the diversity of obstructive sleep apnea (OSA) patients’ characteristics and phenotypes. The objective of this proof-of-concept study was to design a new bench test for realistically simulating an OSA patient’s night, and to implement a one-night example of a typical female phenotype for comparing responses to several currently-available APAP devices. We developed a novel approach aimed at replicating a typical night of sleep which includes different disturbed breathing events, disease severities, sleep/wake phases, body postures and respiratory artefacts. The simulated female OSA patient example that we implemented included periods of wake, light sleep and deep sleep with positional changes and was connected to ten different APAP devices. Flow and pressure readings were recorded; each device was tested twice. The new approach for simulating female OSA patients effectively combined a wide variety of disturbed breathing patterns to mimic the response of a predefined patient type. There were marked differences in response between devices; only three were able to overcome flow limitation to normalize breathing, and only five devices were associated with a residual apnea-hypopnea index of <5/h. In conclusion, bench tests can be designed to simulate specific patient characteristics, and typical stages of sleep, body position, and wake. Each APAP device behaved differently when exposed to this controlled model of a female OSA patient, and should lead to further understanding of OSA treatment. 相似文献
2.
An investigation of Dodonaea viscosa afforded a new flavonoid having an isoprenoid side chain along with the seven known flavonoids: 5-hydroxy-3,6, 相似文献
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4.
Dinesh S. Bhoj Mohammad Ahsanullah 《Biometrical journal. Biometrische Zeitschrift》1993,35(3):355-359
The test statistics are proposed for testing the equality of the coefficients of variation of two normal populations based on independent samples. The asymptotic distributions of the statistics are approximated by well-known distributions. The empirical sizes and powers of these statistics are computed and compared. 相似文献
5.
The association of interleukin-1β (IL-1B) -511C?>?T and IL-1 receptor antagonist (IL-1RN) VNTR, transforming growth factor-β (TGF-B1) +28C?>?T and interferon-γ (IFN-G)?+?874T>A polymorphisms with bladder cancer (CaB) susceptibility and risk of recurrence in Bacillus Calmette–Guérin (BCG)-treated patients was analyzed in 287 controls and 213 CaB patients (73 BCG treated). Increased risk was observed with the IL-1RN*2 allele (odds ratio (OR) 5.01) and the IFN-G +874 A allele (OR 1.78). TGF-B TT and IFN-G +874 A carriers were associated with reduced (hazard ratio (HR) 0.37) and enhanced (HR 2.24) risk of recurrence after BCG immunotherapy, respectively. The study suggests that cytokine gene variants may modulate CaB susceptibility and risk of recurrence after BCG immunotherapy. 相似文献
6.
Dinesh S. Bhoj 《Biometrical journal. Biometrische Zeitschrift》1989,31(3):279-288
Two statistics are proposed for testing the hypothesis of equality of the means of a bivariate normal distribution with unknown common variance and correlation coefficient when observations are missing on both variates. One of the statistics reduces to the one proposed by Bhoj (1978, 1984) when the unpaired observations on the variates are equal. The distributions of the statistics are approximated by well known distributions under the null hypothesis. The empirical powers of the tests are computed and compared with those of some known statistics. The comparison supports the use of one of the statistics proposed in this paper. 相似文献
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8.
Susmita K. Singh Dinesh K. Tripathi Pramod K. Singh Sharad Sharma Kishore K. Srivastava 《Applied microbiology and biotechnology》2013,97(13):5825-5837
The proline-glutamic acid (PE) and proline-proline-glutamic acid (PPE) multi-gene families code for approximately 10 % of the Mycobacterium tuberculosis (Mtb) genome. These proteins are thought to be virulence factors that participate in impounding the host immune responses. While some members have been studied, the functions of most PE/PPE proteins are yet to be explored. The studies presented here have specifically characterized the roles of one of the PE proteins of Mtb, Rv0160c (PE4), in mycobacterial persistence and in prophylactic efficacy. We have expressed Rv0160c in a non-pathogenic fast-growing Mycobacterium smegmatis strain and demonstrated that the protein improves the survival of mycobacteria in macrophages and in mice. The protein has also shown its effect under physiological stress of bacteria, as evidenced by elevated expression in acidic and in hypoxic conditions. In mice, the level of Rv0160c was noticeably high during the chronic stage of tuberculosis. The seroreactivity of the protein against different categories of tuberculosis patients revealed a strong B-cell humoral response in freshly infected pulmonary tuberculosis patients. In mice, it exhibited increased IL-2, TNF, and IL-6 production. The antigenic properties of the protein directed towards the protective efficacy against the Mtb challenge. All together, our findings have identified Rv0160c as an in vivo expressed immunodominant antigen which plays a crucial role in the pathogenesis of mycobacterial disease and could prove to be a good preventive antigen for tuberculosis. 相似文献
9.
Ramesh Prasad Pandey Sailesh Malla Dinesh Simkhada Byung-Gee Kim Jae Kyung Sohng 《Applied microbiology and biotechnology》2013,97(5):1889-1901
Quercetin, a flavonol aglycone, is one of the most abundant flavonoids with high medicinal value. The bioavailability and pharmacokinetic properties of quercetin are influenced by the type of sugars attached to the molecule. To efficiently diversify the therapeutic uses of quercetin, Escherichia coli was harnessed as a production factory by the installation of various plant and bacterial UDP-xylose sugar biosynthetic genes. The genes encoding for the UDP-xylose pathway enzymes phosphoglucomutase (nfa44530), glucose-1-phosphate uridylyltransferase (galU), UDP-glucose dehydrogenase (calS8), and UDP-glucuronic acid decarboxylase (calS9) were overexpressed in E. coli BL21 (DE3) along with a glycosyltransferase (arGt-3) from Arabidopsis thaliana. Furthermore, E. coli BL21(DE3)/?pgi, E. coli BL21(DE3)/?zwf, E. coli BL21(DE3)/?pgi?zwf, and E. coli BL21(DE3)/?pgi?zwf?ushA mutants carrying the aforementioned UDP-xylose sugar biosynthetic genes and glycosyltransferase and the galU-integrated E. coli BL21(DE3)/?pgi host harboring only calS8, calS9, and arGt-3 were constructed to enhance whole-cell bioconversion of exogeneously supplied quercetin into 3-O-xylosyl quercetin. Here, we report the highest production of 3-O-xylosyl quercetin with E. coli BL21 (DE3)/?pgi?zwf?ushA carrying UDP-xylose sugar biosynthetic genes and glycosyltransferase. The maximum concentration of 3-O-xylosyl quercetin achieved was 23.78 mg/L (54.75 μM), representing 54.75 % bioconversion, which was an ~4.8-fold higher bioconversion than that shown by E. coli BL21 (DE3) with the same set of genes when the reaction was carried out in 5-mL culture tubes with 100 μM quercetin under optimized conditions. Bioconversion was further improved by 98 % when the reaction was scaled up in a 3-L fermentor at 36 h. 相似文献
10.
Yongqi Deng Zhiwei Yang Gerald W. Shipps Sie-Mun Lo Robert West Joyce Hwa Shuqin Zheng Constance Farley Jean Lachowicz Margaret van Heek Alan S. Bass Dinesh P. Sinha Craig R. Mahon Mark E. Cartwright 《Bioorganic & medicinal chemistry letters》2013,23(3):791-796
Inhibitors based on a benzo-fused spirocyclic oxazepine scaffold were discovered for stearoyl-coenzyme A (CoA) desaturase 1 (SCD1) and subsequently optimized to potent compounds with favorable pharmacokinetic profiles and in vivo efficacy in reducing the desaturation index in a mouse model. Initial optimization revealed potency preferences for the oxazepine core and benzylic positions, while substituents on the piperidine portions were more tolerant and allowed for tuning of potency and PK properties. After preparation and testing of a range of functional groups on the piperidine nitrogen, three classes of analogs were identified with single digit nanomolar potency: glycine amides, heterocycle-linked amides, and thiazoles. Responding to concerns about target localization and potential mechanism-based side effects, an initial effort was also made to improve liver concentration in an available rat PK model. An advanced compound 17m with a 5-carboxy-2-thiazole substructure appended to the spirocyclic piperidine scaffold was developed which satisfied the in vitro and in vivo requirements for more detailed studies. 相似文献