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91.
Kumar KS Rambabu D Sandra S Kapavarapu R Krishna GR Basaveswara Rao MV Chatti K Reddy CM Misra P Pal M 《Bioorganic & medicinal chemistry》2012,20(5):1711-1722
A direct and single-step method has been developed for the synthesis of mono and 2,3-disubstituted quinoxalines by using a AlCl(3) induced (hetero)arylation of 2,3-dichloroquinoxaline. Both symmetrical and unsymmetrical 2,3-disubstituted quinoxalines can be prepared conveniently by using this method under appropriate reaction conditions. The reaction proceeds via C-C bond formation and can be utilized for the preparation of a variety of quinoxaline derivatives from readily available starting materials and reagents. The molecular structure of a representative compound was confirmed by single crystal X-ray diffraction study. Some of the compounds synthesized were tested for chorismate mutase inhibitory properties in vitro and one compound showed promising activity representing one of the few examples of chorismate mutase inhibition by a heteroarene based small molecule. 相似文献
92.
Kumar KS Kiran Kumar S Yogi Sreenivas B Gorja DR Kapavarapu R Rambabu D Rama Krishna G Reddy CM Basaveswara Rao MV Parsa KV Pal M 《Bioorganic & medicinal chemistry》2012,20(7):2199-2207
A number of 2-(1H-indol-3-yl)quinoline-3-carbonitrile derivatives were synthesized via AlCl(3)-mediated C-C bond forming reaction between 2-chloroquinoline-3-carbonitrile and various indoles. The methodology does not require any N-protection of the indoles employed and provided the corresponding products in good yields. The molecular structure of a representative compound was established unambiguously by single crystal X-ray diffraction and structural elaboration of a compound synthesized has been demonstrated. Many of these compounds synthesized showed PDE4 inhibitory properties in vitro. A brief structure-activity relationship studies within the series along with docking results of a representative compound (EC(50) ~0.89 μM) is presented. 相似文献
93.
94.
E11/gp38 selective expression in osteocytes: regulation by mechanical strain and role in dendrite elongation 总被引:3,自引:0,他引:3 下载免费PDF全文
Zhang K Barragan-Adjemian C Ye L Kotha S Dallas M Lu Y Zhao S Harris M Harris SE Feng JQ Bonewald LF 《Molecular and cellular biology》2006,26(12):4539-4552
Within mineralized bone, osteocytes form dendritic processes that travel through canaliculi to make contact with other osteocytes and cells on the bone surface. This three-dimensional syncytium is thought to be necessary to maintain viability, cell-to-cell communication, and mechanosensation. E11/gp38 is the earliest osteocyte-selective protein to be expressed as the osteoblast differentiates into an osteoid cell or osteocyte, first appearing on the forming dendritic processes of these cells. Bone extracts contain large amounts of E11, but immunostaining only shows its presence in early osteocytes compared to more deeply embedded cells, suggesting epitope masking by mineral. Freshly isolated primary osteoblasts are negative for E11 expression but begin to express this protein in culture, and expression increases with time, suggesting differentiation into the osteocyte phenotype. Osteoblast-like cell lines 2T3 and Oct-1 also show increased expression of E11 with differentiation and mineralization. E11 is highly expressed in MLO-Y4 osteocyte-like cells compared to osteoblast cell lines and primary osteoblasts. Differentiated, mineralized 2T3 cells and MLO-Y4 cells subjected to fluid flow shear stress show an increase in mRNA for E11. MLO-Y4 cells show an increase in dendricity and elongation of dendrites in response to shear stress that is blocked by small interfering RNA specific to E11. In vivo, E11 expression is also increased by a mechanical load, not only in osteocytes near the bone surface but also in osteocytes more deeply embedded in bone. Maximal expression is observed not in regions of maximal strain but in a region of potential bone remodeling, suggesting that dendrite elongation may be occurring during this process. These data suggest that osteocytes may be able to extend their cellular processes after embedment in mineralized matrix and have implications for osteocytic modification of their microenvironment. 相似文献
95.
A combined HPLC-UV/PAD and HPLC-ESI/MS method allowing the fast detection and identification/structural characterisation of lignans of different structural subclasses is described. Twenty-four lignans of different skeletal types were analysed and the combined information derived from their UV and ESI/MS spectra led to the identification of group characteristics that can be used to establish the structure of unknown lignans in plant samples. This method was successfully applied to the identification of lignans in crude extracts of Linum usitatissimum L. and L. bienne Mill. 相似文献
96.
Enhanced single copy integration events in corn via particle bombardment using low quantities of DNA 总被引:3,自引:0,他引:3
Brenda A. Lowe N. Shiva Prakash Melissa Way Michael T. Mann T. Michael Spencer Raghava S. Boddupalli 《Transgenic research》2009,18(6):831-840
Transgene copy number is an important criterion for determining the utility of transgenic events. Single copy integration
events are highly desirable when the objective is to produce marker free plants through segregation or when it is necessary
to introgress different transgenes into commercial cultivars from different transgenic events. In contrast multi-copy events
are advocated by several authors for higher expression of the transgene. Till recently, it was thought that employment of
the particle gun for transformation results in the production of a high proportion of multi-copy events often with complex
integration pattern when compared to Agrobacterium-mediated transformation. However, it has been demonstrated that usage of cassette DNA for bombardment in place of whole plasmids
would result in simple insertion pattern of the transgenes. While investigating the effect of varying the cassette DNA amount
on stable transformation, the frequency of occurrence of low copy events was observed to increase when lower doses of cassette
DNA was employed for bombardment. Large scale experimentation with rigorous statistical analysis performed to verify the above
observations employing Helium gun and the Electric discharge gun for gene delivery confirmed the above observations. Helium
gun experiments involving production of more than 1,600 corn events consistently yielded single copy events at higher frequencies
at lower cassette DNA load (46% at 2.5 ng/shot) as compared to higher cassette DNA load (29% at 25 ng/shot) across 18 independent
experiments. Results were nearly identical with the Electric discharge particle gun device where single copy events were recovered
at frequencies of 54% at 2.5 ng cassettes DNA per shot as compared to 18% at 25 ng cassette DNA per shot. The transformation
frequency declined from 41 to 34% (Helium gun) and from 48 to 31% (Electric discharge gun) with reduction in cassette DNA
quantity from 25 to 2.5 ng per shot. This reduction in the transformation frequency is more than compensated by the savings
in time and effort involved in the production and screening of events if the desired outcome is single copy events. These
results demonstrate the flexibility of the particle gun method for controlling the frequency of production of either low copy
or high copy events by altering the quantity of cassette DNA used for bombardment. The transgene expression levels over generations
in relation to its integration need further investigations. 相似文献
97.
Sharanagouda S. Patil Rajamani Shinduja Kuralayanapalya Puttahonnappa Suresh Sulekha Phukan Sachin Kumar Pinaki Prasad Sengupta Raghavendra G. Amachawadi Ashwin Raut Parimal Roy Asad Syed Najat Marraiki Abdallah M. Elgorban Helal F. Al-Harthi Ali H. Bahkali Chandan Shivamallu Kollur Shiva Prasad 《Saudi Journal of Biological Sciences》2021,28(9):5131-5144
The Indian poultry industry is one of the fast-growing sectors of which duck farming plays an important role. Duck population in India is 33.51 million that is concentrated towards north-east and southern parts of the country who rears mainly for eggs and meat. Duck diseases are of great concern as they badly affect the financial status of the small, landless farmers. Databases such as Google Scholar, PubMed, J gate were used to search articles between 2000 and 2019 that showed the prevalence of viral, bacterial, and parasitic duck diseases. R open source software was used to derive forest plots by statistical analysis. Pooled prevalence estimates of duck diseases worldwide was found to be 20% (95%-CI:15–26). Also, continent-wise analysis of all duck diseases has revealed highest prevalence in North America, followed by Asia, Africa, Europe,Oceania and South America. This prevalence of data would be helpful to the policymakers to develop appropriate intervention strategies to prevent and control diseases in their respective locations. 相似文献
98.
Denise Campbell-Scherer Yvonne Chiu Nicole Naadu Ofosu Thea Luig Karen Heather Hunter Badi Jabbour Sauleha Farooq Ali Mahdi Aline Gayawira Fransiska Awasis Funke Olokude Hannah Goa Hina Syed Judy Sillito Lydia Yip Lyn Belle Mawien Akot Monique Nutter Nadia Farhat Yan Wang Niga Jalal Saida Khalif Shiva Chapagain Stephanie Fernandez Susan Azarcon Zhewar Hama 《CMAJ》2021,193(31):E1203
BACKGROUND:The COVID-19 pandemic has exacerbated disparities in poverty and illness for people in vulnerable circumstances in ethnocultural communities. We sought to understand the evolving impacts of COVID-19 on ethnocultural communities to inform intersectoral advocacy and community action.METHODS:The Illuminate Project used participatory action research, with cultural health brokers as peer researchers, from Sept. 21 to Dec. 31, 2020, in Edmonton, Alberta. Twenty-one peer researchers collected narratives from members of ethnocultural communities and self-interpreted them as they entered the narratives into the SenseMaker platform, a mixed-method data collection tool. The entire research team analyzed real-time, aggregate, quantitative and qualitative data to identify emerging thematic domains, then visualized these domains with social network analysis.RESULTS:Brokers serving diverse communities collected 773 narratives. Identified domains illuminate the evolving and entangled impacts of COVID-19 including the following: COVID-19 prevention and management; care of acute, chronic and serious illnesses other than COVID-19; maternal care; mental health and triggers of past trauma; financial insecurity; impact on children and youth and seniors; and legal concerns. We identified that community social capital and cultural brokering are key assets that facilitate access to formal health and social system supports.INTERPRETATION:The Illuminate Project has illustrated the entangled, systemic issues that result in poor health among vulnerable members of ethnocultural communities, and the exacerbating effects of COVID-19, which also increased barriers to mitigation. Cultural brokering and community social capital are key supports for people during the COVID-19 pandemic. These findings can inform policy to reduce harm and support community resiliency.Mahatma Gandhi observed that “the true measure of any society can be found in how it treats its most vulnerable members.” Ethnocultural communities, defined by their unique shared characteristics (e.g., cultural traditions, language, country of origin),1 face greater challenges and have higher rates of poverty and illness than the general Canadian population. Migration results in conditions that affect all social determinants of health and disproportionally affect health outcomes, herein referred to as vulnerable circumstances.2,3 The emergence of major outbreaks of SARS-CoV-2 infections in ethnocultural communities highlights both the vulnerable circumstances of these communities and the disparities they face in accessing high-quality, culturally appropriate information and support.4–7 Studies have shown substantial variation in deaths attributed to COVID-19 based on factors such as age, sex, ethnicity, length of time in Canada, income and education.8–11 However, given the well-known gap in reporting comprehensive COVID-19 data in relation to race and ethnicity, efforts to measure its impact are hampered.8–12 There is an urgent need to understand the evolving challenges of COVID-19 to inform action and public policy that can mitigate these challenges.To understand evolving situations of complexity and crisis, sensemaking, defined as “a continuous process to establish situational awareness,”13 is a crucial undertaking.14 Using participatory action research,15–18 we sought to understand the evolving impacts of COVID-19 on ethnocultural communities to inform broader national efforts to migitate the impacts of COVID-19. Particularly, we sought to understand how the challenges of COVID-19 are entangled with contextual factors at multiple levels, how families and communities are leveraging strengths and social capital to adapt, and the role of cultural brokers in managing the crisis. 相似文献
99.
Jeffrey H Ruth Christy C Park M Asif Amin Charles Lesch Hubert Marotte Shiva Shahrara Alisa E Koch 《Arthritis research & therapy》2010,12(3):R118
Introduction
The function of interleukin-18 (IL-18) was investigated in pertinent animal models of rodent rheumatoid arthritis (RA) to determine its proinflammatory and monocyte recruitment properties. 相似文献100.
Insulin-like growth factor-I and binding proteins 1, 2, and 3 in bovine nuclear transfer pregnancies
Ravelich SR Breier BH Reddy S Keelan JA Wells DN Peterson AJ Lee RS 《Biology of reproduction》2004,70(2):430-438
In cloned pregnancies, placental deficiencies, including increased placentome size, reduced placentome number, and increased accumulation of allantoic fluid, have been associated with low cloning efficiency. To assess differences in paracrine and endocrine growth regulation in cloned versus normal bovine placentomes and pregnancies, we have examined the expression of insulin-like growth factor (IGF)-I and -II and their binding proteins (IGFBP)-1 through -3 in placentomes of artificially inseminated (AI), in vitro-produced (IVP), and nuclear transfer (NT) pregnancies at Days 50, 100, and 150 of gestation. Fetal, maternal, and binucleate cell counts in representative placentomes were performed on Days 50-150 of gestation in all three groups. Increased numbers of fetal, maternal, and binucleate cells were present in NT placentomes at all stages of gestation examined. Immunolocalization studies showed that spatial and temporal patterns of expression of IGFBP-2 and -3 were markedly altered in the placentomes of NT pregnancies compared to AI/IVP controls. Concentrations of IGF-I in fetal plasma, as determined by RIA, were significantly higher (P = 0.001) in NT pregnancies (mean +/- SEM, 30.3 +/- 2.3 ng/ml) compared with AI (19.1 +/- 5.5 ng/ml) or IVP (24.2 +/- 2.5 ng/ml) pregnancies on Day 150 of gestation. Allantoic fluid levels of IGFBP-1 were also increased in NT pregnancies. These findings suggest that endocrine and paracrine perturbations of the IGF axis may modulate placental dysfunction in NT pregnancies. Furthermore, increased cell numbers in NT placentomes likely have significant implications for fetomaternal communication and may contribute to the placental overgrowth observed in the NT placentomes. 相似文献