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141.
Ramularia is a species-rich genus in the order Capnodiales (Dothideomycetes, Ascomycota) that includes numerous phytopathogenic taxa, several of which are economically important plant pathogens. In this study, six isolates of Ramularia were recovered from leaf spot symptoms on six herbaceous and woody plants from Guilan, East and West Azarbaijan provinces in the north and northwest of Iran. The isolates were studied by a polyphasic approach involving morphological and cultural data, and multi-gene phylogeny (ITS, TEF1-α, ACT, HIS, RPB2 and GAPDH). The isolates were grouped in three species clades of the R. eucalypti species complex. Of these, R. mali is recorded for the first time in Asia and R. glennii represents a new record for the mycobiota of Iran. Ramularia taleshina on Alnus subcordata is described as a new species. Ramularia taleshina is phylogenetically related to R. mali, but they can be differentiated by morphological and cultural characters as well as molecular data. Acalypha australis, Ficus carica and Platanus sp. are reported as new hosts of R. glennii, and Prunus cerasus and Vitis vinifera as new hosts of R. mali.  相似文献   
142.
143.
Salicylates are novel biologically active compounds that exhibit multiple therapeutic activities. The anti-cancer effectiveness of calcium salicylate has been investigated on human HT-1080 fibrosarcoma cell lines at relatively low concentrations (predominantly 0.4 mM) compared to those previously reported. Although low calcium salicylate concentrations did not retard tumour growth progression significantly, as measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and time-lapse assays, its cytotoxic characteristics were proven to be prominent by various morphological and immunocytological techniques. The results here demonstrate evidence for approximately 25% apoptosis after treatment with calcium salicylate, which up-regulatd the expression of p53, p21 and Bax, and down-regulated Bcl-2 in HT-1080 cells.  相似文献   
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145.
Polypyrrole multi-walled carbon nanotube composite layers were used to modify the gold layer to measure heavy metal ions using the surface plasmon resonance technique. The new sensor was fabricated to detect trace amounts of mercury (Hg), lead (Pb), and iron (Fe) ions. In the present research, the sensitivity of a polypyrrole multi-walled carbon nanotube composite layer and a polypyrrole layer were compared. The application of polypyrrole multi-walled carbon nanotubes enhanced the sensitivity and accuracy of the sensor for detecting ions in an aqueous solution due to the binding of mercury, lead, and iron ions to the sensing layer. The Hg ion bonded to the sensing layer more strongly than did the Pb and Fe ions. The limitation of the sensor was calculated to be about 0.1 ppm, which produced an angle shift in the region of 0.3° to 0.6°.  相似文献   
146.
Placental growth factor (PlGF) is a member of the vascular endothelial growth factor (VEGF) family. Unlike VEGF, PlGF is dispensable for normal cell development as well as playing various roles in pathological angiogenesis which occurs in tissue ischemia, inflammation, and malignancy. The PlGF-1 has been considered as a potential candidate for the diagnosis and targeting of pathological angiogenesis. Camelidae serum contains an important fraction of functional antibodies, called heavy-chain antibodies (HcAbs) that are naturally devoid of light chains. Camelid HcAbs recognize their cognate antigens by a single variable-domain, referred to as VHH or Nanobody.Here, we describe the expression and purification of recombinant human PlGF-1 (rhPlGF-1). This protein was subsequently used for the preparation of camel heavy chain polyclonal antibody against rhPlGF-1.The recombinant expression plasmid pET-26b-hPlGF-1 was introduced into Escherichia coli BL21 cells to express the rhPlGF-1 protein. Purified rhPlGF-1 was used to immunize camel, the specific reactivity of HcAb was determined with ELISA and western blot. Western blot analysis indicated that the antiserum specifically reacted to the recombinant protein. The rhPlGF-1 protein and its antibody may be used for the development of detection assays needed for clinical research.  相似文献   
147.

Background:

The gold standard for detection of bladder cancer is cystoscopy, which is an invasive and complicated procedure. Our study was conducted to find a tumor marker with high specificity, sensitivity, and accuracy for the diagnosis of bladder cancer.

Methods:

Serum samples were collected from 58 bladder cancer patients and 60 healthy control subjects. Levels of lipid-bound sialic acid (LBSA), and protein-bound sialic acid (PBSA) were measured spectrophotometrically by Aminoff’s method.

Results:

Mean levels of both markers were found to be significantly higher in the patients than the healthy controls. Positive correlations were observed between serum levels of lipid- (r=0.283, p<0.05) and protein- bound (r=0.56, p<0.05) sialic acids and the grade of malignancy. To differentiate patients with bladder tumors from healthy controls, cut-offpoints were determined for each of the two parameters based on Receiver Operating Characteristic (ROC) curve analysis (LBSA=21.25 mg/dL, PBSA=6.15 mg/dL). The data showed good sensitivities (LBSA=89%, PBSA=79%), specificities (LBSA=70%, PBSA=70%) and accuracies (LBSA=83%, PBSA=81%) for both markers.

Conclusion:

Measuring serum LBSA and PBSA by this simple, reproducible, noninvasive, and inexpensive method can accurately discriminate cancer patients from healthy individuals. Key Words: Urinary Bladder Neoplasms, N-Acetylneuraminic Acid, Tumor Markers  相似文献   
148.
The PALB2 tumor suppressor plays key roles in DNA repair and has been implicated in redox homeostasis. Autophagy maintains mitochondrial quality, mitigates oxidative stress and suppresses neurodegeneration. Here we show that Palb2 deletion in the mouse brain leads to mild motor deficits and that co-deletion of Palb2 with the essential autophagy gene Atg7 accelerates and exacerbates neurodegeneration induced by ATG7 loss. Palb2 deletion leads to elevated DNA damage, oxidative stress and mitochondrial markers, especially in Purkinje cells, and co-deletion of Palb2 and Atg7 results in accelerated Purkinje cell loss. Further analyses suggest that the accelerated Purkinje cell loss and severe neurodegeneration in the double deletion mice are due to excessive oxidative stress and mitochondrial dysfunction, rather than DNA damage, and partially dependent on p53 activity. Our studies uncover a role of PALB2 in mitochondrial homeostasis and a cooperation between PALB2 and ATG7/autophagy in maintaining redox and mitochondrial homeostasis essential for neuronal survival.  相似文献   
149.
Molecular Biology Reports - Alzheimer's disease is a common neurodegenerative disease in the elderly population and a leading cause of dementia. Genetics and environmental risk factors were...  相似文献   
150.

Background aims

Adipose tissue–derived mesenchymal stromal cells (AT-MSCs), widely known as multipotent progenitors, release several cytokines that support cell survival and repair. There are in vitro and in vivo studies reporting the regenerative role of AT-MSCs possibly mediated by their protective effects on functional islet cells as well as their capacity to differentiate into insulin-producing cells (IPCs).

Methods

On such a basis, our goal in the present study was to use three different models including direct and indirect co-cultures and islet-derived conditioned medium (CM) to differentiate AT-MSCs into IPCs and to illuminate the molecular mechanisms of the beneficial impact of AT-MSCs on pancreatic islet functionality. Furthermore, we combined in vitro co-culture of islets and AT-MSCs with in vivo assessment of islet graft function to assess whether co-transplantation of islets with AT-MSCs can reduce marginal mass required for successful islet transplantation and prolong graft function in a diabetic rat model.

Results

Our findings demonstrated that AT-MSCs are suitable for creating a microenvironment favorable for the repair and longevity of the pancreas β cells through the improvement of islet survival and maintenance of cell morphology and insulin secretion due to their potent properties in differentiation. Most importantly, hybrid transplantation of islets with AT-MSCs significantly promoted survival, engraftment and insulin-producing function of the graft and reduced the islet mass required for reversal of diabetes.

Conclusions

This strategy might be of therapeutic potential solving the problem of donor islet material loss that currently limits the application of allogeneic islet transplantation as a more widespread therapy for type 1 diabetes.  相似文献   
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