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41.
In the present work, we provide compelling evidence for the expression of a ghrelin-like peptide hormone that has only been associated with animals, in various plant tissues. Ghrelin, the appetite stimulating hormone, has been identified from a number of different species including humans, rat, pig, mouse, gerbil, eel, goldfish, bullfrog and chicken. The study here was conducted using an immunohistochemistry assay to screen whether plants have any ghrelin immunoreactivity. In this respect, Prunus x domestica L. and Marus alba were examined. Immunohistochemistry results showed that there is a strong human ghrelin immunoreactivity substance in the parenchyma cells of these plants. This was entirely unexpected since this hormone was considered to be present solely in animals. Thus, this study is the first to report the presence of a peptide with ghrelin-like activity in plants, a finding that has only been observed in the animal kingdom. RIA analysis confirmed that these plants contain significant amounts of this substance. Furthermore, reverse-phase HPLC analyses of plant extracts showed an elution characteristic of the peptide identical to that of human ghrelin. In general, fruit from both plants had higher levels of the peptide than the vegetative parts.  相似文献   
42.
This study reports a novel method for embryo separation by cold treatment of heterogeneous suspension cultures which contain embryogenic single cells, cell clusters and embryos at various stages of development. The method was applied to embryo suspension cultures of pepper (Capsicum annuum) and sugarcane (Saccharum officinarum). In both plants, single cells lost their viability dramatically over a few days while the viability of embryos remained above 95% for 25-30 days when kept at 5 °C. The effect of duration of cold treatment on embryo germination was also tested. The optimal duration of cold treatment was found to be 10 days for sugarcane and 21 days for pepper. After the cold treatment, the germination percentages were 90% and 96% for sugarcane and pepper, respectively.  相似文献   
43.
Comprehensive genetic testing has the potential to become the standard of care for individuals with hearing loss. In this study, we investigated the genetic etiology of autosomal recessive nonsyndromic hearing loss (ARNSHL) in a Turkish cohort including individuals with cochlear implant, who had a pedigree suggestive of an autosomal recessive inheritance. A workflow including prescreening of GJB2 and a targeted next generation sequencing panel (Illumına TruSightTM Exome) covering 2761 genes that we briefly called as mendelian exome sequencing was used. This panel includes 102 deafness genes and a number of genes causing Mendelian disorders. Using this approach, we identified causative variants in 21 of 29 families. Three different GJB2 variants were present in seven families. Remaining 14 families had 15 different variants in other known NSHL genes (MYO7A, MYO15A, MARVELD2, TMIE, DFNB31, LOXHD1, GPSM2, TMC1, USH1G, CDH23). Of these variants, eight are novel. Mutation detection rate of our workflow is 72.4%, confirming the usefulness of targeted sequencing approach in NSHL.  相似文献   
44.
Mucormycosis is increasingly common in patients with risk factors such as diabetes mellitus, neutropenia, and corticosteroid therapy. However, mucormycosis seems to be less common in patients with human immunodeficiency virus (HIV) infection compared to patients with other risk factors. Despite their lower virulence, Lichtheimia species should be regarded as emerging pathogens among Mucoralean fungi. We report a fatal case of pulmonary mucormycosis due to Lichtheimia ramosa in a 52-year-old man with an end-stage HIV infection. He had a cachectic appearance and his CD4 count was 8 cells/mm3. The fungal infection was diagnosed based on a positive sputum culture with histopathologic confirmation. The fungus was resistant to caspofungin, anidulafungin, and voriconazole [minimum inhibitory concentration (MCI) >32 µg/ml], whereas the E test MIC values of itraconazole, posaconazole, and amphotericin B were 0.38, 0.38, and 0.5 µg/ml, respectively. Although intravenous drug use is the main risk factor for the development of mucormycosis in HIV-infected patients, it may also develop in patients with low CD4 count, opportunistic infections and/or additional diseases, such as Kaposi’s sarcoma or severe immunodeficiency, as in our case.  相似文献   
45.
Familial Mediterranean Fever (FMF) which is frequently present in Mediterranean populations is caused by mutations in the MEFV gene. According to recent data, MEFV mutations are not the only cause of FMF, but these are major genetic determinants which cause FMF. It has also been suggested that there may be a number of other genes causing FMF. The MEFV gene is located at 16p13.3 and encodes a protein, pyrin/marenostrin. More than 70 disease associated mutations and totally 186 mutations and polymorphisms have been defined in affected individuals. We have retrospectively evaluated the molecular test results of 1,201 patients identified as having FMF clinical symptoms referred to the Molecular Genetics Laboratory of the Department of Medical Genetics, Faculty of Medicine, Ege University, Izmir/Turkey over the last 4 years. Patients were tested for 12 common mutations in the MEFV gene using a strip assay method (Innogenetics, Belgium). Out of the 1,201 patients tested (2,402 chromosomes) in the Aegean region in Turkey, 654 (54.45%) did not carry any mutations, among the 547 (45.55%) patients with mutations 246 patients were either homozygous (101) or compound heterozygous (145), 296 carried only one detected mutation, and five patients had three mutations. Allelic frequencies for the four most common mutations in the mutation positive groups were 47.60% (M694V), 16.75% (E148Q), 12.95% (V726A), 11.94% (M680I G/C).The remaining alleles (10.76%) showed rare mutations which were R761H, P369S, A744S, K695R, F479L, M694I. When the frequencies of mutations detected in our group were compared to the frequencies reported in the other regions of Turkey, an increase in V726A mutation frequency was observed. No patient showed a I692del mutation which is sometimes evident in other Mediterranean populations.  相似文献   
46.
47.
Syndecan-4 is an ubiquitous, plasma membrane-spanning heparan sulfate proteoglycan involved in proliferation, differentiation, adhesion and migration of cells in vitro. Syndecan-4 knockout (KO) mice show no obvious defects but respond abnormally to experimental stress conditions. In the adult, syndecan-4 is the most abundant syndecan of renal tissue. We therefore investigated the consequences of syndecan-4 deficiency during progression of kidney disease using unilaterally nephrectomized mice, a model of glomerular hyperfiltration and renal hypertrophy. 60 days after unilateral nephrectomy (UNX), mesangial expansion, enhanced matrix production (collagens I and IV, fibronectin) and focal segmental glomerulosclerosis, resembling early stages of diabetic nephropathy, was apparent in male but not female syndecan-4 KO mice. No defect was detected in wild type UNX males. Syndecan-2 mRNA and protein were not detectable in renal glomeruli of wild type mice, but were induced specifically in the glomeruli of the syndecan-4 deficient kidneys after unilateral nephrectomy. Due to the structural similarities of syndecans-2 and -4 we hypothesize that de novo-production of syndecan-2 in kidneys after unilateral nephrectomy reflects a compensatory response. However, this response is counterproductive since syndecan-2 supports the pro-sclerotic activity of TGF-beta1 which is increased in parallel with syndecan-2 synthesis. By contrast, signaling through syndecan-4 negatively controls the production of pro-sclerotic TGF-beta1.  相似文献   
48.
The outcomes of breast cancer patients are still poor although new compounds have recently been introduced into the clinic. Therefore, novel chemical approaches are required. In the present study, palladium(II) and corresponding platinum(II) complexes containing bis(2-pyridylmethyl)amine (bpma) and saccharine were synthesized and tested against human breast cancer cell lines, MCF-7 and MDA-MB-231, in vitro. Cytotoxicity was first screened by the MTT assay and the results were further confirmed by the ATP assay. The palladium complexes 1 and 3 yielded stronger cytotoxicity than the corresponding platinum complexes 2 and 4 at the same doses. The palladium complex 3 was found to be the most cytotoxic one. Therefore, a more comprehensive study was carried out with this complex only. The mode of cell death was determined morphologically under fluorescent microscope and biochemically with detection of active caspase-3 and PARP cleavage by Western blot. Changes in apoptosis-related gene expressions were measured with qPCR. It was demonstrated that complex 3 caused cell death by apoptosis determined by fluorescence imaging and Western blot. As a sign of apoptosis, PARP was cleaved in both of the cell lines. In addition, caspase-3 was cleaved in MDA-MB-231 cells while this cleavage was not observed in MCF-7. The results show that the complex 3 is a promising anti-cancer compound against breast cancer with an IC50 value of 3.9 μM for MCF-7 and 4.2 μM for MDA-MB-231 cells, which warrants further animal experiments.  相似文献   
49.

Purpose

Although deep vein thrombosis and thromboembolic diseases differ among various races, they are still important in our day. The difficulties in treatment and following-up of these diseases are caused by secret genetic mutations rather than predisposing factors.

Methods

Between January 2011 and May 2013, patients who were traced for deep vein thrombosis and/or pulmonary embolism were evaluated retrospectively. 84 patients (53.6% males and 46.4% females) were included in the study. Their family histories, predisposing factors and treatments were researched. Factor V Leiden (G 1691A), Factor II G20210A, Plasminogen Activator Inhibitor-Type 1 (4G/5G), and Methylene Tetrahydrofolate Reductase (C677T, A1298C) mutations were investigated from peripheral venous blood.

Results

Among the genetic mutations we searched, the incidence of single mutation rate was observed at 11.9%, double mutation collocation at 44%, triple mutation collocation at 29.8%, quadruple mutation collocation at 13.1%, and finally, quintuplet mutation collocation at 1.2%. Our approximate mutation number was found as 2.47 ± 0.91.

Conclusion

We observed that multiple mutations were high in number compared to single genetic mutations. The patients who have multiple mutations should be more in the front line considering their diagnosis, treatment and following up, and also in terms of decreasing mortality, morbidity and recurrence.  相似文献   
50.
Studies on postmortem brains from Parkinson's patients reveal elevated iron in the substantia nigra (SN). Selective cell death in this brain region is associated with oxidative stress, which may be exacerbated by the presence of excess iron. Whether iron plays a causative role in cell death, however, is controversial. Here, we explore the effects of iron chelation via either transgenic expression of the iron binding protein ferritin or oral administration of the bioavailable metal chelator clioquinol (CQ) on susceptibility to the Parkinson's-inducing agent 1-methyl-4-phenyl-1,2,3,6-tetrapyridine (MPTP). Reduction in reactive iron by either genetic or pharmacological means was found to be well tolerated in animals in our studies and to result in protection against the toxin, suggesting that iron chelation may be an effective therapy for prevention and treatment of the disease.  相似文献   
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