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151.
Scott H Visovatti Oliver Distler J Gerry Coghlan Christopher P Denton Ekkehard Grünig Diana Bonderman Ulf Müller-Ladner Janet E Pope Madelon C Vonk James R Seibold Juan-Vicente Torres-Martin Martin Doelberg Harbajan Chadha-Boreham Daniel M Rosenberg Vallerie V McLaughlin Dinesh Khanna 《Arthritis research & therapy》2014,16(6)
Introduction
Patients with mean pulmonary artery pressures (mPAP) of 21 to 24 mm Hg have a so-called borderline elevation of mPAP (BoPAP)—a condition thought to represent early-stage pulmonary arterial vasculopathy. Based on the DETECT study, this post-hoc analysis examined patient characteristics of systemic sclerosis (SSc) patients with normal mPAP, BoPAP and elevated mPAP, fulfilling pulmonary arterial hypertension (PAH) criteria.Methods
Adult patients with a duration of SSc more than 3 years, a diffusing capacity of the lung for carbon monoxide less than 60% predicted, and no previous diagnosis of any form of pulmonary hypertension (PH) underwent screening tests followed by right heart catheterization. Subjects were divided into three groups: normal mPAP, BoPAP, and PAH. Exploratory comparative and binary logistic regression analyses were performed for the BoPAP versus normal mPAP and PAH versus BoPAP groups.Results
Of 244 patients evaluated, 148 (60%) had normal mPAP, 36 (15%) had BoPAP, and 60 (25%) had definite PAH. Univariable logistic regression (ULR) showed the mean tricuspid regurgitation velocity in patients with BoPAP to be intermediate between normal mPAP and PAH. In the ULR analyses BoPAP versus normal mPAP and PAH versus BoPAP, the statistically significant predictors were, amongst others: demographic, clinical, pulmonary function, echocardiographic and hemodynamic variables.Conclusions
In this exploratory post-hoc analysis of the DETECT study population patients with BoPAP could be distinguished from patients with normal mPAP and PAH, and it appears that BoPAP may be an intermediate stage on the continuum between normal PA pressures and PAH.Electronic supplementary material
The online version of this article (doi:10.1186/s13075-014-0493-1) contains supplementary material, which is available to authorized users. 相似文献152.
Neeraj Raizada Kuldeep Singh Sachdeva Sreenivas Achuthan Nair Shubhangi Kulsange Radhey Shayam Gupta Rahul Thakur Malik Parmar Christen Gray Ranjani Ramachandran Bhavin Vadera Shobha Ekka Shikha Dhawan Ameet Babre Mayank Ghedia Umesh Alavadi Puneet Dewan Mini Khetrapal Ashwini Khanna Catharina Boehme Chinnambedu Nainarappan Paramsivan 《PloS one》2014,9(8)
Background
Diagnosis of pulmonary tuberculosis (PTB) in children is challenging due to difficulties in obtaining good quality sputum specimens as well as the paucibacillary nature of disease. Globally a large proportion of pediatric tuberculosis (TB) cases are diagnosed based only on clinical findings. Xpert MTB/RIF, a highly sensitive and specific rapid tool, offers a promising solution in addressing these challenges. This study presents the results from pediatric groups taking part in a large demonstration study wherein Xpert MTB/RIF testing replaced smear microscopy for all presumptive PTB cases in public health facilities across India.Methods
The study covered a population of 8.8 million across 18 programmatic sub-district level tuberculosis units (TU), with one Xpert MTB/RIF platform established at each study TU. Pediatric presumptive PTB cases (both TB and Drug Resistant TB (DR-TB)) accessing any public health facilities in study area were prospectively enrolled and tested on Xpert MTB/RIF following a standardized diagnostic algorithm.Results
4,600 pediatric presumptive pulmonary TB cases were enrolled. 590 (12.8%, CI 11.8–13.8) pediatric PTB were diagnosed. Overall 10.4% (CI 9.5–11.2) of presumptive PTB cases had positive results by Xpert MTB/RIF, compared with 4.8% (CI 4.2–5.4) who had smear-positive results. Upfront Xpert MTB/RIF testing of presumptive PTB and presumptive DR-TB cases resulted in diagnosis of 79 and 12 rifampicin resistance cases, respectively. Positive predictive value (PPV) for rifampicin resistance detection was high (98%, CI 90.1–99.9), with no statistically significant variation with respect to past history of treatment.Conclusion
Upfront access to Xpert MTB/RIF testing in pediatric presumptive PTB cases was associated with a two-fold increase in bacteriologically-confirmed PTB, and increased detection of rifampicin-resistant TB cases under routine operational conditions across India. These results suggest that routine Xpert MTB/RIF testing is a promising solution to present-day challenges in the diagnosis of PTB in pediatric patients. 相似文献153.
154.
155.
Bagchi D Roy S Patel V He G Khanna S Ojha N Phillips C Ghosh S Bagchi M Sen CK 《Molecular and cellular biochemistry》2006,281(1-2):197-209
Edible berry extracts rich in anthocyanins possess a broad spectrum of therapeutic, pharmacologic and anti-carcinogenic properties.
Six berry extracts (wild blueberry, bilberry, cranberry, elderberry, raspberry seeds and strawberry), singly and in combination,
were studied in our laboratories for antioxidant efficacy, cytotoxic potential, cellular uptake and anti-angiogenic properties.
Combinations of edible berry extracts were evaluated to develop a synergistic formula, OptiBerry, which exhibited high oxygen
radical absorbance capacity (ORAC) value, low cytotoxicity and superior anti-angiogenic properties compared to the other combinations
tested. The current study sought to determine the broad spectrum safety and antioxidant potential of OptiBerry in vivo. Acute oral LD50 of OptiBerry was greater than 5 g/kg in rats. Acute dermal LD50 of OptiBerry was greater than 2 g/kg. No changes in the body weight or adverse effects were observed following necropsy.
Primary skin and eye irritation studies were conducted in New Zealand albino rabbits. OptiBerry was classified as slightly
irritating to the skin (primary skin irritation index 0.3) and minimally irritating to the eye (maximum mean total score 6.0).
The antioxidant potential of OptiBerry was investigated in rats and mice by assessing GSH redox status in tissues as well
as by a unique state-of-the-art electron paramagnetic resonance (EPR) imaging of whole-body redox status. A clinically relevant
hyperbaric oxygen (HBO) exposure system (2 atm, 2 h) was employed to study the antioxidant properties of OptiBerry. OptiBerry
feeding (8 weeks) significantly prevented HBO-induced GSH oxidation in the lung and liver of vitamin E-deficient Sprague Dawley
rats. Furthermore, OptiBerry-fed mice, when exposed to HBO, demonstrated significant protection in whole-body HBO-induced
oxidation compared to the unfed controls by EPR imaging. Taken together, these results indicate that OptiBerry is reasonably
safe and possess antioxidant properties. 相似文献
156.
Human embryonic stem cells (hESCs) can differentiate into cardiomyocytes, but the efficiency of this process is highly variable. So, developing generic differentiation protocols and their empirical testing on a range of independently derived hESC lines pose a daunting challenge due to considerable diversity in culture methods practiced between lines. Maintenance of BG01V and ReliCellhES1 has routinely been on mouse embryonic fibroblast (MEF) feeder layers using manual passaging. We assessed cardiac differentiation from both the cell lines via embryoid body (EB) formation. Subsequent culture in low fetal bovine serum (5%)-containing medium produced spontaneously contracting EBs, in the presence of bone morphogenetic protein-2 (BMP-2; 25 ng/ml). Derived cardiomyocytes expressed cardiac genes and proteins and responded to functional assays. Further, the activation of the Smad signaling machinery evoked by BMP-2 has been confirmed through inhibitor studies. Therefore, in our hands, the same differentiation conditions functioned in two independently derived hESC lines. Similar studies in other lines may facilitate development of universal protocols. The present data may also provide valuable insights for testing of other factors that might promote cardiomyocyte differentiation in low-serum formulations. 相似文献
157.
Golden bananas in the field: elevated fruit pro‐vitamin A from the expression of a single banana transgene 下载免费PDF全文
Jean‐Yves Paul Harjeet Khanna Jennifer Kleidon Phuong Hoang Jason Geijskes Jeff Daniells Ella Zaplin Yvonne Rosenberg Anthony James Bulukani Mlalazi Pradeep Deo Geofrey Arinaitwe Priver Namanya Douglas Becker James Tindamanyire Wilberforce Tushemereirwe Robert Harding James Dale 《Plant biotechnology journal》2017,15(4):520-532
Vitamin A deficiency remains one of the world's major public health problems despite food fortification and supplements strategies. Biofortification of staple crops with enhanced levels of pro‐vitamin A (PVA) offers a sustainable alternative strategy to both food fortification and supplementation. As a proof of concept, PVA‐biofortified transgenic Cavendish bananas were generated and field trialed in Australia with the aim of achieving a target level of 20 μg/g of dry weight (dw) β‐carotene equivalent (β‐CE) in the fruit. Expression of a Fe'i banana‐derived phytoene synthase 2a (MtPsy2a) gene resulted in the generation of lines with PVA levels exceeding the target level with one line reaching 55 μg/g dw β‐CE . Expression of the maize phytoene synthase 1 (ZmPsy1) gene, used to develop ‘Golden Rice 2’, also resulted in increased fruit PVA levels although many lines displayed undesirable phenotypes. Constitutive expression of either transgene with the maize polyubiquitin promoter increased PVA accumulation from the earliest stage of fruit development. In contrast, PVA accumulation was restricted to the late stages of fruit development when either the banana 1‐aminocyclopropane‐1‐carboxylate oxidase or the expansin 1 promoters were used to drive the same transgenes. Wild‐type plants with the longest fruit development time had also the highest fruit PVA concentrations. The results from this study suggest that early activation of the rate‐limiting enzyme in the carotenoid biosynthetic pathway and extended fruit maturation time are essential factors to achieve optimal PVA concentrations in banana fruit. 相似文献
158.
Caffeine abolishes the mammalian G(2)/M DNA damage checkpoint by inhibiting ataxia-telangiectasia-mutated kinase activity 总被引:18,自引:0,他引:18
Zhou BB Chaturvedi P Spring K Scott SP Johanson RA Mishra R Mattern MR Winkler JD Khanna KK 《The Journal of biological chemistry》2000,275(14):10342-10348
Recent evidence indicates that arrest of mammalian cells at the G(2)/M checkpoint involves inactivation and translocation of Cdc25C, which is mediated by phosphorylation of Cdc25C on serine 216. Data obtained with a phospho-specific antibody against serine 216 suggest that activation of the DNA damage checkpoint is accompanied by an increase in serine 216 phosphorylated Cdc25C in the nucleus after exposure of cells to gamma-radiation. Prior treatment of cells with 2 mM caffeine inhibits such a change and markedly reduces radiation-induced ataxia-telangiectasia-mutated (ATM)-dependent Chk2/Cds1 activation and phosphorylation. Chk2/Cds1 is known to localize in the nucleus and to phosphorylate Cdc25C at serine 216 in vitro. Caffeine does not inhibit Chk2/Cds1 activity directly, but rather, blocks the activation of Chk2/Cds1 by inhibiting ATM kinase activity. In vitro, ATM phosphorylates Chk2/Cds1 at threonine 68 close to the N terminus, and caffeine inhibits this phosphorylation with an IC(50) of approximately 200 microM. Using a phospho-specific antibody against threonine 68, we demonstrate that radiation-induced, ATM-dependent phosphorylation of Chk2/Cds1 at this site is caffeine-sensitive. From these results, we propose a model wherein caffeine abrogates the G(2)/M checkpoint by targeting the ATM-Chk2/Cds1 pathway; by inhibiting ATM, it prevents the serine 216 phosphorylation of Cdc25C in the nucleus. Inhibition of ATM provides a molecular explanation for the increased radiosensitivity of caffeine-treated cells. 相似文献
159.
Counter-immunoelectrophoresis was employed for the detection of Brucella antigen in stomach contents of aborted buffalo fetuses and antibody in aborted as well as apparently healthy in contact buffaloes. Five of 16 aborted cases were serologically positive for brucellosis but isolation of Brucella abortus was successful in only two cases. By counter-immunoelectrophoresis, Brucella antigen was detected in the fetal stomach contents of four serologically positive cases. Of the 68 serum samples from in contact healthy buffaloes, 10 were positive with counter-immunoelectrophoresis: more than were detected by tube agglutination, Rose Bengal plate agglutination, complement fixation and agar gel precipitation test. 相似文献
160.
Sebastian Patzke Sambra Redick Abdirashid Warsame Carlos A. Murga-Zamalloa Hemant Khanna Stephen Doxsey Trond Stokke 《Molecular biology of the cell》2010,21(15):2555-2567
We described previously the cell cycle- and microtubule-related functions of two splice isoforms of the centrosome spindle pole-associated protein (CSPP and CSPP-L). Here, we show that endogenous CSPP isoforms not only localize to centrosomes and the midbody in cycling cells but also extend to the cilia axoneme in postmitotic resting cells. They are required for ciliogenesis in hTERT-RPE1 cells in vitro and are expressed in ciliated renal, retinal, and respiratory cells in vivo. We report that CSPP isoforms require their common C-terminal domain to interact with Nephrocystin 8 (NPHP8/RPGRIP1L) and to form a ternary complex with NPHP8 and NPHP4. We find CSPP-L to be required for the efficient localization of NPHP8 but not NPHP4 to the basal body. The ciliogenesis defect in hTERT-RPE1 cells is, however, not mediated through loss of NPHP8. Similar to the effects of ectopical expression of CSPP-L, cilia length increased in NPHP8-depleted cells. Our results thus suggest that CSPP proteins may be involved in further cytoskeletal organization of the basal body and its primary cilium. To conclude, we have identified a novel, nonmitotic function of CSPP proteins placing them into a ciliary protein network crucial for normal renal and retinal tissue architecture and physiology. 相似文献