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101.
S.?L.?KothariEmail author Kalpana?Agarwal Satish?Kumar 《In vitro cellular & developmental biology. Plant》2004,40(5):515-519
Summary Growth and morphogenesis of plant tissues under in vitro conditions are largely influenced by the composition of the culture media. In this study, effects of different inorganic
nutrients (ZnSO4 and CuSO4) on callus induction and plant regeneration of Eleusine coracana in vitro were examined. Primary callus induction without ZnSO4 resulted in improved shoot formation upon transfer of calluses to normal regeneration medium. CuSO4 increased to 5x the normal concentration in the media for primary seed callus induction and plant regeneration resulted in
a 4-fold increase in number of regnnerated shoots. For long-term callus cultures, 2x KNO3 or 4x Fe-EDTA could replace the requirement for α-naphthaleneacetic acid in the regeneration medium, while 60 μM ZnSO4 or 0.5 μM CuSO4 was optimal for plant regeneration from callus cultures. 相似文献
102.
Bing Lai Rakhi Agarwal Lindsay D. Nelson Subramanyam Swaminathan Erwin London 《The Journal of membrane biology》2010,236(2):191-201
Botulinum neurotoxins (BoNTs) undergo low pH-triggered membrane insertion, resulting in the translocation of their light (catalytic)
chains into the cytoplasm. The T (translocation) domain of the BoNT heavy chain is believed to carry out translocation. Here,
the behavior of isolated T domain from BoNT type A has been characterized, both in solution and when associated with model
membranes. When BoNT T domain prepared in the detergent dodecylmaltoside was diluted into aqueous solution, it exhibited a
low pH-dependent conformational change below pH 6. At low pH the T domain associated with, and formed pores within, model
membrane vesicles composed of 30 mol% dioleoylphosphatidylglycerol/70 mol% dioleoylphosphatidylcholine. Although T domain
interacted with vesicles at low (50 mM) and high (400 mM) NaCl concentrations, the interaction required much less lipid at
low salt. However, even at high lipid concentrations pore formation was much more pronounced at low NaCl concentrations than
at high NaCl concentration. Increasing salt concentration after insertion in the presence of 50 mM NaCl did not decrease pore
formation. A similar effect of NaCl concentration upon pore formation was observed in vesicles composed solely of dioleoylphosphatidylcholine,
showing that the effect of NaCl did not solely involve modulation of electrostatic interactions between protein and anionic
lipids. These results indicate that some feature of membrane-bound T domain tertiary structure critical for pore formation
is highly dependent upon salt concentration. 相似文献
103.
P. K. Sarma, A. K. Chowhan, V. Agrawal and V. Agarwal Fine needle aspiration cytology in HIV‐related lymphadenopathy: experience at a single centre in north India Objective: Fine needle aspiration (FNA) is emerging as a rapid and minimally invasive tool in evaluating lymphadenopathy associated with human immunodeficiency virus (HIV). We evaluated the role of FNA in differentiating various causes of lymphadenopathy in patients with HIV and correlated the cytological diagnosis with CD4 counts. Methods: Seventy‐nine HIV‐positive patients (median age 35 years, 68 male) underwent ultrasound‐guided (n = 16) and unguided (n = 63) FNA from 1999 to 2006. Smears were stained with May–Grünwald–Giemsa, haematoxylin & eosin and Papanicolaou stains. Ziehl–Neelsen (ZN) staining for acid‐fast bacilli (AFB) was performed in all cases. Staining for fungus was performed whenever required. Results: The aspirates were adequate in 75 cases (95%). Non‐specific reactive hyperplasia was the most common FNA diagnosis (39, 52%) followed by granulomatous necrotizing lymphadenitis (15, 20%), necrotizing lymphadenitis (13, 17.3%) and granulomatous lymphadenitis (4, 5.2%). Fungal infection and non‐Hodgkin lymphoma (NHL) were seen in two patients each. ZN staining was positive for AFB in 25 (33.3%) cases. One of these was morphologically interpreted as reactive hyperplasia, 12 as necrotizing lymphadenitis and 12 as granulomatous necrotizing lymphadenitis. Both patients with NHL had CD4 counts below 100/dl. Necrotizing lymphadenitis and granulomatous lymphadenitis were significantly associated with CD4 counts below and above 200/dl, respectively (P = 0.0002). Conclusions: FNA is an important tool for assessing the cause of lymphadenopathy in HIV patients. Necrotizing inflammation is more often seen in patients with low CD4 counts. AFB are commonly found in necrotic aspirates with or without granulomas. However, a stain for AFB should be performed in all aspirates from HIV‐related lymphadenopathy including reactive hyperplasia. 相似文献
104.
The implications of the methylene tetrahydrofolate reductase (MTHFR) gene and the level of homocysteine in the pathogenesis of coronary artery disease (CAD) have been extensively studied in various ethnic groups. Our aim was to discover the association of MTHFR (C677T) polymorphism and homocysteine level with CAD in north Indian subjects. The study group consisted of 329 angiographically proven CAD patients, and 331 age and sex matched healthy individuals as controls. MTHFR (C677T) gene polymorphism was detected based on the polymerase chain reaction and restriction digestion with HinfI. Total homocysteine plasma concentration was measured using immunoassay. T allele frequency was found to be significantly higher in patients than in the control group. We found significantly elevated levels of mean homocysteine in the patient group when compared to the control group (p = 0.00). Traditional risk factors such as diabetes, hypertension, smoking habits, a positive family history and lipid profiles (triglyceride, total cholesterol, HDL-cholesterol, LDL-cholesterol, VLDL-cholesterol), were found significantly associated through univariate analysis. Furthermore, multivariable logistics regression analysis revealed that CAD is significantly and variably associated with diabetes, hypertension, smoking, triglycerides and HDL-cholesterol. Our findings showed that MTHFR C677T polymorphism and homocysteine levels were associated with coronary artery disease in the selected population. 相似文献
105.
Vibrio cholerae MARTX toxin heterologous translocation of beta‐lactamase and roles of individual effector domains on cytoskeleton dynamics 下载免费PDF全文
Jazel S. Dolores Shivani Agarwal Martina Egerer Karla J. F. Satchell 《Molecular microbiology》2015,95(4):590-604
The Vibrio cholerae MARTXVc toxin delivers three effector domains to eukaryotic cells. To study toxin delivery and function of individual domains, the rtxA gene was modified to encode toxin with an in‐frame beta‐lactamase (Bla) fusion. The hybrid RtxA::Bla toxin was Type I secreted from bacteria; and then Bla was translocated into eukaryotic cells and delivered by autoprocessing, demonstrating that the MARTXVc toxin is capable of heterologous protein transfer. Strains that produce hybrid RtxA::Bla toxins that carry one effector domain in addition to Bla were found to more efficiently translocate Bla. In cell biological assays, the actin cross‐linking domain (ACD) and Rho‐inactivation domain (RID) are found to cross‐link actin and inactivate RhoA, respectively, when other effector domains are absent, with toxin autoprocessing required for high efficiency. The previously unstudied alpha‐beta hydrolase domain (ABH) is shown here to activate CDC42, although the effect is ameliorated when RID is also present. Despite all effector domains acting on cytoskeleton assembly, the ACD was sufficient to rapidly inhibit macrophage phagocytosis. Both the ACD and RID independently disrupted polarized epithelial tight junction integrity. The sufficiency of ACD but strong selection for retention of RID and ABH suggests these two domains may primarily function by modulating cell signaling. 相似文献
106.
A birth during the day by a capped langur (Trachypithecus pileatus Blyth, 1843) was recorded at Pakhui Wildlife Sanctuary, Arunachal Pradesh, India. The birth took 43 min. Allomothering was observed 3 h after the birth. An average of 9% of daily active time was shared by four allomothers (three adults, one subadult) during the first 15 days of the infants life. Total time allomothering was proportional to the age of the allomothers (241 min for oldest; 214 min for youngest). 相似文献
107.
108.
Shouvik Das Hari D. Upadhyaya Deepak Bajaj Alice Kujur Saurabh Badoni Laxmi Vinod Kumar Shailesh Tripathi C. L. Laxmipathi Gowda Shivali Sharma Sube Singh Akhilesh K. Tyagi Swarup K. Parida 《DNA research》2015,22(3):193-203
A rapid high-resolution genome-wide strategy for molecular mapping of major QTL(s)/gene(s) regulating important agronomic traits is vital for in-depth dissection of complex quantitative traits and genetic enhancement in chickpea. The present study for the first time employed a NGS-based whole-genome QTL-seq strategy to identify one major genomic region harbouring a robust 100-seed weight QTL using an intra-specific 221 chickpea mapping population (desi cv. ICC 7184 × desi cv. ICC 15061). The QTL-seq-derived major SW QTL (CaqSW1.1) was further validated by single-nucleotide polymorphism (SNP) and simple sequence repeat (SSR) marker-based traditional QTL mapping (47.6% R2 at higher LOD >19). This reflects the reliability and efficacy of QTL-seq as a strategy for rapid genome-wide scanning and fine mapping of major trait regulatory QTLs in chickpea. The use of QTL-seq and classical QTL mapping in combination narrowed down the 1.37 Mb (comprising 177 genes) major SW QTL (CaqSW1.1) region into a 35 kb genomic interval on desi chickpea chromosome 1 containing six genes. One coding SNP (G/A)-carrying constitutive photomorphogenic9 (COP9) signalosome complex subunit 8 (CSN8) gene of these exhibited seed-specific expression, including pronounced differential up-/down-regulation in low and high seed weight mapping parents and homozygous individuals during seed development. The coding SNP mined in this potential seed weight-governing candidate CSN8 gene was found to be present exclusively in all cultivated species/genotypes, but not in any wild species/genotypes of primary, secondary and tertiary gene pools. This indicates the effect of strong artificial and/or natural selection pressure on target SW locus during chickpea domestication. The proposed QTL-seq-driven integrated genome-wide strategy has potential to delineate major candidate gene(s) harbouring a robust trait regulatory QTL rapidly with optimal use of resources. This will further assist us to extrapolate the molecular mechanism underlying complex quantitative traits at a genome-wide scale leading to fast-paced marker-assisted genetic improvement in diverse crop plants, including chickpea. 相似文献
109.
Gupta Saurabh Chaubey Kundan Kumar Agarwal Prabhat Kuenstner J. Todd Parashar Deepak Singh Shoor Vir 《Molecular biology reports》2021,48(10):7013-7020
Molecular Biology Reports - A 26-year-old male had a history of frequent bowel movements, mushy stool with mucus and loss of 25 kg body weight in 6 months was diagnosed as a case... 相似文献
110.
Pratima Labroo David Hilgart Brett Davis Christopher Lambert Himanshu Sant Bruce Gale Jill E. Shea Jayant Agarwal 《Biotechnology and bioengineering》2019,116(1):143-154
Autologous nerve grafts are the current “gold standard” for repairing large nerve gaps. However, they cause morbidity at the donor nerve site and only a limited amount of nerve can be harvested. Nerve conduits are a promising alternative to autografts and can act as guidance cues for the regenerating axons, without the need to harvest donor nerve. Separately, it has been shown that localized delivery of GDNF can enhance axon growth and motor recovery. FK506, an FDA approved small molecule, has also been shown to enhance peripheral nerve regeneration. This paper describes the design of a novel hole-based drug delivery apparatus integrated with a polytetrafluoroethylene (PTFE) nerve conduit for controlled local delivery of a protein such as GDNF or a small molecule such as FK506. The PTFE devices were tested in a diffusion chamber, and the bioactivity of the released media was evaluated by measuring neurite growth of dorsal root ganglions (DRGs) exposed to the released drugs. The drug delivering nerve guide was able to release bioactive concentrations of FK506 or GDNF. Following these tests, optimized drug releasing nerve conduits were implanted across 10 mm sciatic nerve gaps in a BL6 yellow fluorescent protein (YFP) mouse model, where they demonstrated significant improvement in muscle mass, compound muscle action potential, and axon myelination in vivo as compared with nerve conduits without the drug. The drug delivery nerve guide could release drug for extended periods of time and enhance axon growth in vitro and in vivo. 相似文献