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361.
The diagnosis of human hydatidosis is primarily made using radiological and serological methods. Radiological methods are generally of low specificity and serological methods lack sensitivity, especially for pulmonary disease. In this study the capabilities of a new rapid test, the hydatid antigen dot immunobinding assay (HADIA), which was developed for the diagnosis of pulmonary hydatidosis, were studied and compared with another immunodiagnostic method, indirect hemagglutination (IHA). The study subjects included 18 patients, 9 women, 9 men; range 7 to 63 years; mean 30 years, with surgically proven pulmonary hydatidosis, a control group comprised of 14 patients; viral respiratory infections (1), cirrhosis (2), connective tissue disease (2), taeniasis (3), and 6 healthy donors. We found that the HA-DIA test had a sensitivity of 67% and specificity of 100%, and that the IHA test had a sensitivity of 50% and specificity of 100%. We conclude that HA-DIA is a simple, rapid, low cost assay that does not require instrumentation and has a higher sensitivity than IHA for the diagnosis of pulmonary hydatidosis. 相似文献
362.
Bone sialoprotein (BSP) is a multifunctional, highly phosphorylated, and glycosylated protein with key roles in biomineralization and tissue remodeling. This work identifies the complete topographical distribution and precise location of both the in vitro and in vivo phosphorylation sites of bovine BSP by a combination of state-of-the-art techniques and approaches. In vitro phosphorylation of native and deglycosylated BSPs by casein kinase II identified seven phosphorylation sites by solid-phase N-terminal peptide sequencing that were within peptides 12-22 (LEDS(P)EENGVFK), 42-62 (FAVQSSSDSS(P)EENGNGDS(P)S(P)EE), 80-91 (EDS(P)DENEDEES(P)E), and 135-145 (EDES(P)DEEEEEE). The in vivo phosphorylation regions and sites were identified by use of a novel thiol reagent, 1-S-mono[(14)C]carboxymethyldithiothreitol. This approach identified all of the phosphopeptides defined by in vitro phosphorylation, but two additional phosphopeptides were defined at residues, 250-264 (DNGYEIYES(P)ENGDPR), and 282-289 (GYDS(P)YDGQ). Furthermore, use of native BSP and matrix-assisted laser desorption ionization time-of-flight mass spectrometry identified several of the above peptides, including an additional phosphopeptide at residues 125-130 (AGAT(P)GK) that was not defined in either of the in vitro and in vivo studies described above. Overall, 7 in vitro and 11 in vivo phosphorylation sites were identified unequivocally, with natural variation in the quantitative extent of phosphorylation at each in vivo phosphorylation site. 相似文献
363.
Ömür Çelikbıçak Kadriye Özlem Hamaloğlu Bekir Salih 《Nucleosides, nucleotides & nucleic acids》2020,39(7):1057-1072
AbstractThe aim of this study is to develop a methodology in which Surface Plasmon Resonance (SPR), Ellipsometer (EM) and Matrix-Assisted Laser Desorption/Ionization-Mass Spectrometry (MALDI-MS) will be used together for detection of single-strand oligodeoxynucleotides (ssODNs) targets. A selected target-ssODNs, and its complementary, the probe-ssODNs carrying a -SH end group, a spacer arm (HS-(CH2)6–(T)15, and a non-complementary ssODNs were used. Silicone based stamps with 16 regions were prepared and used for micro-contact printing (µCP) of the probe-ssODNs on the gold coated surfaces homogeneously. A modulator-spacer molecule (6-mercapto-1-hexanol) was co-immobilized to control surface probe density, to orientate the probe-ssODNs, and to eliminate the nonspecific interactions. SPR was used successfully to follow the hybridization of the target-ssODNs with the immobilized probe-ssODNs on the platform surfaces. Complete hybridizations were achieved in 100?min. It was obtained that there was a linear relationship between relative change in delta and target concentration below 1?µm. Using imaging version of ellipsometer (IEM) allowed imaging of the surfaces and supported extra datum for the SPR results. After a very simple dehybridization protocol, MALDI-MS analysis allowed detection of the target-ssODNs hybridized on the sensor/array platforms. 相似文献
364.
Ahmet Var Ozan Ütük Sinem Akçalı Tamer Şanlıdağ Bekir S. Uyanık Gönül Dinç 《Molecular biology reports》2009,36(8):2235-2243
Single point mutations in the genes coding for hemostatic factors were shown to be major inherited predisposing factors for
venous thromboembolism. However, their contribution in the development of non-diabetic coronary artery disease [nDCAD] remains
controversial. Angiographically demonstrated nDCAD patients (n = 86) and healthy controls (n = 90) were included in the study. Genotype analysis of hemostatic gene polymorphisms were assessed by using CVD strip assay,
based on allele specific oligonucleotide probes. The carrier frequency of factor V (FV) H1299R, prothrombin G20210A, glycoprotein
(Gp) IIIa L33P, plasminogen activator inhibitor-I (PAI-1) 4G/5G, 4G/4G, 5G/5G, methylenetetrahydrofolate reductase (MTHFR)
A1298C and β-fibrinogen −455 G > A were similar between patients and controls. In contrast, frequency of FV Leiden was significantly
higher among patients (12.5%) than controls (5%, OR: 7.94; 95%CI: 1.9–49.6) and FXIII V34L was significantly lower among patients
(23.7%) than controls (40%, OR: 0.24; 95%CI: 0.1–0.89). In addition, the frequency of the MTHFR C677T polymorphism was 32.5%
among patients compared with 42.5% in controls, of which the T/T genotype was significantly lower among patients (5%) than
controls (17.5%, OR: 0.06; 95%CI: 0.01–0.58). No difference was observed in prevalence of prothrombin G20210A, FV H1299R,
Gp IIIa L33P, PAI-1 4G5G, MTHFR A1298C, β fibrinogen 455 G > A mutations between patients and controls. However, lower frequency
of FXIII Val34Leu and MTHFR C677T polymorphisms may decrease, while FV Leiden polymorphism may increase development of nDCAD. 相似文献
365.
Doxorubicin (DXR) is a frontline chemotherapy agent implicated in unintended ovarian failure in female cancer survivors. The fertility preservation techniques currently available for cancer patients are often time and cost prohibitive and do not necessarily preserve endocrine function. There are no drug-based ovary protection therapies clinically available. This study provides the first investigation using dexrazoxane (Dexra) to limit DXR insult in ovarian tissue. In KK-15 granulosa cells, a 3-h DXR treatment increased double-strand (ds) DNA breaks 40%-50%, as quantified by the neutral comet assay, and dose-dependent cytotoxicity. Dexra exhibited low toxicity in KK-15 cells, inducing no DNA damage and less than 20% cell loss. Cotreating KK-15 cells with Dexra prevented acute DXR-induced dsDNA damage. Similarly, Dexra attenuated the DXR-induced 40%-65% increase in dsDNA breaks in primary murine granulosa cells and cells from in vitro cultured murine ovaries. DXR can cause DNA damage either through a topoisomerase II-mediated pathway, based on DXR intercalation into DNA, or through oxidative stress. Cotreating KK-15 cells with 2 μM Dexra was sufficient to prevent DXR-induced, but not H(2)O(2)-induced, DNA damage. These data indicated the protective effects are likely due to Dexra's inhibition of topoisomerase II catalytic activity. This putative protective agent attenuated downstream cellular responses to DXR, preventing H2AFX activation in KK-15 cells and increasing viability as demonstrated by increasing the DXR lethal dose in KK-15 cells 5- to 8-fold (LD(20)) and primary murine granulosa cells 1.5- to 2-fold (LD(50)). These data demonstrate Dexra protects ovarian cells from DXR insult and suggest that it is a promising tool to limit DXR ovarian toxicity in vivo. 相似文献
366.
MC Manzini DE Tambunan RS Hill TW Yu TM Maynard EL Heinzen KV Shianna CR Stevens JN Partlow BJ Barry J Rodriguez VA Gupta AK Al-Qudah WM Eyaid JM Friedman MA Salih R Clark I Moroni M Mora AH Beggs SB Gabriel CA Walsh 《American journal of human genetics》2012,91(3):541-547
Whole-exome sequencing (WES), which analyzes the coding sequence of most annotated genes in the human genome, is an ideal approach to studying fully penetrant autosomal-recessive diseases, and it has been very powerful in identifying disease-causing mutations even when enrollment of affected individuals is limited by reduced survival. In this study, we combined WES with homozygosity analysis of consanguineous pedigrees, which are informative even when a single affected individual is available, to identify genetic mutations responsible for Walker-Warburg syndrome (WWS), a genetically heterogeneous autosomal-recessive disorder that severely affects the development of the brain, eyes, and muscle. Mutations in seven genes are known to cause WWS and explain 50%-60% of cases, but multiple additional genes are expected to be mutated because unexplained cases show suggestive linkage to diverse loci. Using WES in consanguineous WWS-affected families, we found multiple deleterious mutations in GTDC2 (also known as AGO61). GTDC2's predicted role as an uncharacterized glycosyltransferase is consistent with the function of other genes that are known to be mutated in WWS and that are involved in the glycosylation of the transmembrane receptor dystroglycan. Therefore, to explore the role of GTDC2 loss of function during development, we used morpholino-mediated knockdown of its zebrafish ortholog, gtdc2. We found that gtdc2 knockdown in zebrafish replicates all WWS features (hydrocephalus, ocular defects, and muscular dystrophy), strongly suggesting that GTDC2 mutations cause WWS. 相似文献
367.
Nader M Westendorp B Hawari O Salih M Stewart AF Leenen FH Tuana BS 《American journal of physiology. Heart and circulatory physiology》2012,302(5):H1138-H1145
Sarcolemmal membrane-associated proteins (SLMAPs) are components of cardiac membranes involved in excitation-contraction (E-C) coupling. Here, we assessed the role of SLMAP in cardiac structure and function. We generated transgenic (Tg) mice with cardiac-restricted overexpression of SLMAP1 bearing the transmembrane domain 2 (TM2) to potentially interfere with endogenous SLMAP through homodimerization and subcellular targeting. Histological examination revealed vacuolated myocardium; the severity of which correlated with the expression level of SLMAP1-TM2. High resolution microscopy showed dilation of the sarcoplasmic reticulum/endoplasmic reticulum (SR/ER) and confocal imaging combined with biochemical analysis indicated targeting of SLMAP1-TM2 to the SR/ER membranes and inappropriate homodimerization. Older (28 wk of age) Tg mice exhibited reduced contractility with impaired relaxation as assessed by left ventricle pressure monitoring. The ventricular dysfunction was associated with electrophysiological abnormalities (elongated QT interval). Younger (5 wk of age) Tg mice also exhibited an elongated QT interval with minimal functional disturbances associated with the activation of the fetal gene program. They were less responsive to isoproterenol challenge (ΔdP/dt(max)) and developed electrical and left ventricular pressure alternans. The altered electrophysiological and functional disturbances in Tg mice were associated with diminished expression level of calcium cycling proteins of the sarcoplasmic reticulum such as the ryanodine receptor, Ca(2+)-ATPase, calsequestrin, and triadin (but not phospholamban), as well as significantly reduced calcium uptake in microsomal fractions. These data demonstrate that SLMAP is a regulator of E-C coupling at the level of the SR and its perturbation results in progressive deterioration of cardiac electrophysiology and function. 相似文献
368.
Anthony W. D. Larkum Min Chen Yaqiong Li Martin Schliep Erik Trampe John West Anya Salih Michael Kühl 《Journal of phycology》2012,48(6):1320-1327
A new habitat and a new chlorophyll (Chl) d‐containing cyanobacterium belonging to the genus Acaryochloris are reported in this study. Hyperspectral microscopy showed the presence of Chl d‐containing microorganisms in epiphytic biofilms on a red alga (Gelidium caulacantheum) colonizing the pneumato‐phores of a temperate mangrove (Avicennia marina). The presence of Chl d was further proven by high performance liquid chromatography (HPLC)‐based pigment analysis and by confocal imaging of cultured cells. Enrichment of mangrove biofilm samples under near‐infrared radiation (NIR) yielded the new Acaryochloris sp. MPGRS1, which was closely related in terms of 16S rRNA gene sequence to an isolate from the hypertrophic Salton Sea, USA. The new isolate used Chl d as its major photopigment; Chl d and Chl a contents were ~98% and 1%–2% of total cellular chlorophyll, respectively. These findings expand the variety of ecological niches known to harbor Chl d‐containing cyanobacteria and support our working hypothesis that such oxyphototrophs may be ubiquitous in habitats depleted of visible light, but with sufficient NIR exposure. 相似文献
369.
Cyclophosphamide (CP) has potential urotoxicity such as hemorrhagic cystitis (HC). 2-Mercaptoethane sulfonate (mesna) has been widely used as an effective agent against CP-induced cystitis, but significant HC has still been encountered clinically. In recent studies, mesna was shown to be more effective if combined with antioxidants. The purpose of this study was to evaluate the effects of antioxidants, alpha-tocopherol, beta-carotene and melatonin on CP-induced bladder damage in rats, even if used without mesna administration. Male Sprague-Dawley rats weighing 180-210 g were divided into 5 groups. Four groups received a single dose of CP (100 mg/kg) intraperitoneally with the same time intervals. Group 2 received CP only, group 3 received beta-carotene (40 mg/kg/day), group 4 received alpha-tocopherol (40 mg/kg/day) and group 5 received melatonin (10 mg/kg/day) both before and the day after CP injection. Group 1 served as control. Bladder histopathology, as well as malondialdehyde (MDA) and iNOS levels, and excretion of nitrite-nitrates (NO(x)) in urine were evaluated. CP injection resulted in severe histological changes and macroscopic hematuria. alpha-Tocopherol and melatonin showed meaningful protection against bladder damage. Protection by beta-carotene was also significant but weaker. MDA levels increased significantly with CP injection and all antioxidants ameliorated this increase in bladder tissue. CP also elevated the NO(x) level in urine and iNOS activity in bladder. Only melatonin was able to decrease these parameters. In conclusion, there is no doubt that oxidants have a role in the pathogenesis of CP-cystitis. Antioxidants, especially melatonin and alpha-tocopherol, may help to ameliorate bladder damage induced by CP. 相似文献
370.
Cinar B Fang PK Lutchman M Di Vizio D Adam RM Pavlova N Rubin MA Yelick PC Freeman MR 《The EMBO journal》2007,26(21):4523-4534
Akt kinases mediate cell growth and survival. Here, we report that a pro-apoptotic kinase, Mst1/STK4, is a physiological Akt1 interaction partner. Mst1 was identified as a component of an Akt1 multiprotein complex isolated from lipid raft-enriched fractions of LNCaP human prostate cancer cells. Endogenous Mst1, along with its paralog, Mst2, acted as inhibitors of endogenous Akt1. Surprisingly, mature Mst1 as well as both of its caspase cleavage products, which localize to distinct subcellular compartments and are not structurally homologous, complexed with and inhibited Akt1. cRNAs encoding full-length Mst1, and N- and C-terminal caspase Mst1 cleavage products, reverted an early lethal phenotype in zebrafish development induced by expression of membrane-targeted Akt1. Mst1 and Akt1 localized to identical subcellular sites in human prostate tumors. Mst1 levels declined with progression from clinically localized to hormone refractory disease, coinciding with an increase in Akt activation with transition from hormone naïve to hormone-resistant metastases. These results position Mst1/2 within a novel branch of the phosphoinositide 3-kinase/Akt pathway and suggest an important role in cancer progression. 相似文献