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1.
The δ-zein, a minor component of the maize prolamin, shows extensive immunological cross-reactivity with α- and β-zeins. The adsorption of an anti-δ-zein serum sequentially with cross-reacting antigens revealed that only about 18% of the reactivity of the antiserum was directed to epitopes unique to δ-zein. The localization of the various zein classes within the protein bodies of endosperm cells is important to understanding the synthesis, sequestering, and utilization of these storage proteins. Sections of 28 days after pollination (DAP) isolated protein bodies and 18 and 40 DAP whole endosperms were reacted sequentially with whole anti-δ-zein serum and gold-conjugated protein A. The results showed intense gold labeling in the core (inside the peripheral zone) and weak labeling in the periphery of the sections. This localization was not definitive in view of the above-mentioned cross-reactivities. To obtain an unequivocal localization, the whole antiserum was adsorbed with α-, β-, and γ-zeins and rendered monospecific for δ-zein. Immunostaining of protein body sections with monospecific antiserum showed that gold label was exclusively in the core region of the protein body and appeared to be in discrete lines and zones especially in 18 DAP protein bodies. The data from localizations using the monospecific antiserum indicated that δ-zein occurs throughout the core region of the protein body, probably interspersed with α- and β-zeins. The location of δ-zein is consistent with that predicted from its order of degradation during seed germination.  相似文献   
2.
The immunochemical data from studies with polyclonal antisera to -zein1, the 27 kD component of the maize prolamin, indicated that the region containing 8 tandem repeats of the sequence PPPVHL is an immunodominant site. In one case, the entire antibody repertoire of an antiserum recognized epitope(s) within this region. Three 17-mer oligopeptides corresponding to the predicted antigenic epitopes of -zein1 were synthesized and reacted with three different anti--zein1 sera in order to map antigenic sites in the intact protein. These antisera yielded positive reactions with a 17-mer peptide (peptide 37), which was not in a hydrophilic maximum but derived from the repeat region. The same antisera gave little or no reaction with other peptides (peptides 38 and 39), both of which were in a hydrophilic maximum. In addition, an antiserum to peptide 37 reacted strongly with both the homologous antigen and the intact -zein1. Peptide 37 also blocked the binding of antisera to -zein1 in competition assays. Subsequently, the shorter 6-mer (peptide 82) and 12-mer (peptide 80) versions of peptide 37 were synthesized, and both reacted with anti-peptide 37 serum and also with each of the three anti--zein1 sera. In these reactions and in competition assays, the reactivity and the blocking ability increased in proportion to the length of the peptide. Based on these data, it was concluded that the repeat region of -zein1 is the site of one or more continuous immunodominant epitopes. The data also suggest that the repeat region is exposed on the surface of the folded protein and probably occur as a mobile, random coil.  相似文献   
3.
Primary structure of a proline-rich zein and its cDNA   总被引:5,自引:2,他引:3       下载免费PDF全文
Eighty-five cDNA clones for γ-zein (proline-rich zein) from a cDNA expression library were isolated using specific antibody and cDNA probes. Nucleotide sequences of seven independent clones were determined and found to be identical in regions where they overlapped. The primary structure of the mature protein, determined from the sequence of one near full-length clone, consists of 204 amino acids. It has a molecular weight of 21,824 daltons, about 5 kilodaltons less than that estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The N-terminal one-half of the sequence contained eight essentially identical tandem repeats of the hexapeptide Pro-Pro-Pro-Val-His-Leu and two of the octapeptide Gln-Pro-His-Pro-Cys-Pro-Cys-Gln. The codon specifying the third proline in the hexapeptide repeating units is identical (CCG) in all of the eight repeats. The coding region has a very high G-C content (69.8%). The multiple charge components of γ-zein detected by isoelectric focusing do not seem to be encoded by members of a multigene family. Moreover, it was found that the codon preference in γ-zein is, in fact, the base preference in the wobble position. A codon usage value was devised to express this phenomenon.  相似文献   
4.
A thiol compound, glutathione, is essential for healthy cell defence against xenobiotics and oxidative stress. Glutathione reductase (GR) and glutathione S-transferase (GST) are two glutathione-related enzymes that function in the antioxidant and the detoxification systems. In this study, potential inhibitory effects of methyl 4-aminobenzoate derivatives on GR and GST were examined in vitro. GR and GST were isolated from human erythrocytes with 7.63 EU/mg protein and 5.66 EU/mg protein specific activity, respectively. It was found that compound 1 (methyl 4-amino-3-bromo-5-fluorobenzoate with Ki value of 0.325±0.012 μM) and compound 5 (methyl 4-amino-2-nitrobenzoate with Ki value of 92.41±22.26 μM) inhibited GR and GST stronger than other derivatives. Furthermore, a computer-aided method was used to predict the binding affinities of derivatives, ADME characteristics, and toxicities. Derivatives 4 (methyl 4-amino-2-bromobenzoate) and 6 (methyl 4-amino-2-chlorobenzoate) were estimated to have the lowest binding energies into GR and GST receptors, respectively according to results of in silico studies.  相似文献   
5.
BackgroundPhlebotomy is one of the most important steps in the preanalytical phase of a clinical laboratory process. In order to decrease phlebotomy errors, this specific procedure should be taught in detail by laboratory organizations. Our study aims to practice the training program on venous blood sampling and observe the close follow-up results.MethodsIn this observational study, 127 students who started their summer internship in Antalya Education and Research Hospital were given a one-day theoretical phlebotomy training in accordance with the Venous Blood Sampling Guidelines. After the theoretical training, phlebotomy applications of 10 students who were working in the field of out-patient blood sampling were observed both with and without their knowledge. A comprehensive checklist related to phlebotomy was created by the trainers in Antalya Education and Research Hospital and the observers answered each question as yes or no. For the statistical analysis, IBM SPSS Statistics 21.0 was used.ResultsAfter the theoretical education, the trainees were observed but no significant difference was found between the first and the second informed observations (p = 0.125). The students were observed three times more in the following week without their knowledge. There was a statistically significant difference between the first and the third unannounced observations (p=0.001).ConclusionsIn order to perform phlebotomy correctly, apart from theoretical education, a close follow-up is necessary too.  相似文献   
6.

The arthroconidial yeasts Magnusiomyces capitatus and M. clavatus are emerging opportunistic pulmonary pathogens. They are closely related and difficult to distinguish based on morphological and physiological traits. We applied an SYBR® green-based quantitative PCR (qPCR) assay to identify the species. We analyzed 30 reference strains originating from clinical and environmental sources by targeting the Rpb2 gene encoding the second largest subunit of RNA polymerase II. The qPCR assays were tested by direct identification of M. capitatus and M. clavatus in spiked sputum and household dishwasher swabs, respectively, as models for clinical and environmental samples. The assays were proved to be reliable for species-level identification of both species, with 100% sensitivity and 100% specificity, lowest inter-assay deviations (RSDr?≤?1.65%, R2 values >0.99), detection limit of 10 theoretical copy number of target DNA, and detection cell limit of ≥5000 yeast cells from spiked sputum samples. The developed qPCR assay is a practical molecular approach for the detection of M. capitatus and M. clavatus that can be used as a stand-alone assay or in conjunction with culture-dependent approaches.

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7.

Osteoarthritis (OA) is a common condition that impacts many people worldwide and involves weight-bearing joints, resulting in chronic pain. In this study, we aimed to compare the effectiveness of inpatient and outpatient physical therapy modalities and spa combination treatments on pain and functional status in patients with knee osteoarthritis. Seventy-four patients diagnosed with primary knee osteoarthritis were included in this study. The patients were randomized into two groups, inpatient (n?=?37) and outpatient (n?=?37) physical therapy. All patients received a physical therapy program (superficial heater + deep heater + transcutaneous electrical nerve stimulation) for 2 weeks and spa therapy. All cases were evaluated clinically, laboratory, and radiographically. In order to evaluate pain and functional status, the Visual Analogue Scale (VAS), Western Ontario and McMaster Universities osteoarthritis index (WOMAC), and Timed Up and Go (TUG) test were used before and after treatment. There was no significant difference between the two groups in the TUG test and WOMAC scores (p?>?0.05). However, a significant difference was found in VAS scores in favor of the outpatient group (p?<?0.05). As a result, although there was a significant improvement in pain scores in the outpatient group, multicenter studies with larger patient groups may provide more evidence.

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8.
The Mycobacterium tuberculosis complex (MTBC) is a group of related pathogens that cause tuberculosis (TB) in mammals. MTBC species are distinguished by their ability to sustain in distinct host populations. While Mycobacterium bovis (Mbv) sustains transmission cycles in cattle and wild animals and causes zoonotic TB, M. tuberculosis (Mtb) affects human populations and seldom causes disease in cattle. The host and pathogen determinants underlying host tropism between MTBC species are still unknown. Macrophages are the main host cell that encounters mycobacteria upon initial infection, and we hypothesised that early interactions between the macrophage and mycobacteria influence species-specific disease outcome. To identify factors that contribute to host tropism, we analysed blood-derived primary human and bovine macrophages (hMϕ or bMϕ, respectively) infected with Mbv and Mtb. We show that Mbv and Mtb reside in different cellular compartments and differentially replicate in hMϕ whereas both Mbv and Mtb efficiently replicate in bMϕ. Specifically, we show that out of the four infection combinations, only the infection of bMϕ with Mbv promoted the formation of multinucleated giant cells (MNGCs), a hallmark of tuberculous granulomas. Mechanistically, we demonstrate that both MPB70 from Mbv and extracellular vesicles released by Mbv-infected bMϕ promote macrophage multinucleation. Importantly, we extended our in vitro studies to show that granulomas from Mbv-infected but not Mtb-infected cattle contained higher numbers of MNGCs. Our findings implicate MNGC formation in the contrasting pathology between Mtb and Mbv for the bovine host and identify MPB70 from Mbv and extracellular vesicles from bMϕ as mediators of this process.  相似文献   
9.
BackgroundCoronary ischemia can lead to myocardial damage and necrosis. The pathogenesis of cardiovascular diseases often includes increased oxidative stress and decreased antioxidant defense. The study aimed to assess levels of ischemia modified albumin (IMA), malondialdehyde acid (MDA), superoxide dismutase (SOD), and catalase in individuals diagnosed with ST elevated myocardial infarction (STEMI) and non-STEMI.MethodsThe present study prospectively included 50 STEMI patients, 55 NSTEMI patients, and 55 healthy subjects. Only patients who were recently diagnosed with STEMI or NSTEMI were included in this study. IMA, MDA, SOD, and catalase activities were measured spectrophotometrically. Significant coronary artery lesions were determined by angiography.ResultsPatients with ACS had significantly greater IMA and MDA values than the healthy controls (p<0.001). Besides, patients with STEMI had IMA levels that were significantly greater than those of the patients with NSTEMI (p<0.001), while the reverse was true for MDA levels (p<0.001). The healthy controls had the highest levels of SOD and catalase levels, followed by patients with STEMI and patients with NSTEMI, respectively (p<0.001). There was a significant negative correlation among MDA and SOD with catalase levels (r = -0.771 p<0.001 MDA vs catalase; r = -0.821 p<0.001 SOD vs catalase).ConclusionsData obtained in this study reveals that compared to healthy controls, STEMI and NSTEMI patients had increased levels of MDA and IMA and decreased levels of SOD and catalase.  相似文献   
10.
In this study, the findings of three water mite species of the family Hygrobatidae collected from different streams in Turkey were evaluated. Hygrobates (s. str.) anatolicus Esen & Pešić, sp. n. is described as new for science. Hygrobates (Rivobates) diversiporus Sokolow, 1927 and Atractides (s. str.) nikooae Pešić, 2004, which were illustrated and thoroughly discussed, are new records for the Turkish fauna.  相似文献   
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