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101.
The purpose of this study was to investigate the effect of combined Ca2+ cross-linking and freeze-thawing cycle method on metronidazole (model drug) drug release and prepare a wound film dressing with improved swelling property. The hydrogel films were prepared with sodium alginate (SA) using the freeze-thawing method alone or in combination with ionotropic gelation with CaCl2. The gel properties such as morphology, swelling, film thickness, and content uniformity and in vitro dissolution profiles using Franz diffusion cell were investigated. The cross-linking process was confirmed by differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy. In vitro protein adsorption test, in vivo wound-healing test, and histopathology were also performed. The hydrogel (F2) composed of 6% sodium alginate and 1% metronidazole prepared by combined Ca2+ cross-linking and freeze-thawing cycles showed good swelling. This will help to provide moist environment at the wound site. With the in vivo wound-healing and histological studies, F2 was found to improve the wound-healing effect compared with the hydrogel without the drug, and the conventional product.KEY WORDS: alginate, Ca2+ cross-linking, freeze-thawing, swelling, wound dressing  相似文献   
102.
Various circulating biochemical markers are indicators of pathological state in leukemia and its subtypes. Increased oxidative stress and decreased antioxidant factors portray clear image associated with malignancies during subtypes of leukemia. In this research work we investigated the inter-relationship among the subtypes of leukemia with circulating biochemical markers and oxidative stress in the Pakistani population. This research work was conducted on a total number of 70 subjects in which 20 were control participants and 50 were suffering from leukemia and divided into two subtypes (ALL and AML). Various circulating biomarkers were investigated including hematological, hepatic and renal profiles as well as oxidative stress markers, electrolytes and vitamins C and E. Results show that vitamin E was found to be decreased in diseased sub-types (P < 0.05). Malondialdehyde (MDA) levels were very high in disease sub-types (ALL-B = 8.69 ± 1.59; ALL-T = 8.78 ± 0.97; AML = 8.50 ± 1.29) compared to controls (1.22 ± 0.10; P < 0.05) while the levels of antioxidants [superoxide dismutase (SOD), glutathione peroxidase (GPx), reduced glutathione (GSH), catalase (CAT)], platelets, as well as electrolytes (Ca and Mg) were reduced in patients suffering from leukemia (sub-types). Enhanced levels of oxidative stress (MDA) and decreased levels of enzymatic and non-enzymatic antioxidants reflect the pathological state and impaired cell control in patients suffering from leukemia (subtypes) and show a strong correlation with oxidative stress, indicating that patients’ biological systems are under oxidative stress.  相似文献   
103.

Objective

In the present study the physiological parameters, their comparative analysis with carbohydrate and lipid metabolism were studied. This study suggests life style, environmental and genetic adaptations in the studied population.

Method

One hundred and ninety eight subjects were selected from different towns of District Ziarat. General characteristics of the population according to their nutritional habits including, age, body mass index(BMI), systolic blood pressure, diastolic blood pressure, glycemia, triglycerides, serum low density lipoprotein (LDL), high density lipoprotein (HDL), very low density lipoprotein (VLDL), triglycerides (TG) were measured.

Results

Mean cholesterol, LDL, VLDL and triglyceride values were significantly higher in men than women and the values increased with increasing age in both men and women. HDL and glucose values were significantly higher in females than males. In men with various nutritional groups such as A, B and C, the mean cholesterol (P < 0.001), LDL (P < 0.014), VLDL (P < 0.031) and triglyceride (P < 0.025) levels were significantly observed among comparable groups. However, in women with various nutritional groups such as A, B and C, the mean age (P < 0.047) and triglyceride values (P < 0.033) display statistically significant results.  相似文献   
104.
An active medicinal component of plant origin with an ability to overcome autophagy by inducing apoptosis should be considered a therapeutically active lead pharmacophore to control malignancies. In this report, we studied the effect of concentration-dependent 3-AWA (3-azido withaferin A) sensitization to androgen-independent prostate cancer (CaP) cells which resulted in a distinct switching of 2 interrelated conserved biological processes, i.e. autophagy and apoptosis. We have observed 3 distinct parameters which are hallmarks of autophagy in our studies. First, a subtoxic concentration of 3-AWA resulted in an autophagic phenotype with an elevation of autophagy markers in prostate cancer cells. This led to a massive accumulation of MAP1LC3B and EGFP-LC3B puncta coupled with gradual degradation of SQSTM1. Second, higher toxic concentrations of 3-AWA stimulated ER stress in CaP cells to turn on apoptosis within 12 h by elevating the expression of the proapoptotic protein PAWR, which in turn suppressed the autophagy-related proteins BCL2 and BECN1. This inhibition of BECN1 in CaP cells, leading to the disruption of the BCL2-BECN1 interaction by overexpressed PAWR has not been reported so far. Third, we provide evidence that pawr-KO MEFs exhibited abundant autophagy signs even at toxic concentrations of 3-AWA underscoring the relevance of PAWR in switching of autophagy to apoptosis. Last but not least, overexpression of EGFP-LC3B and DS-Red-BECN1 revealed a delayed apoptosis turnover at a higher concentration of 3-AWA in CaP cells. In summary, this study provides evidence that 3-AWA is a strong anticancer candidate to abrogate protective autophagy. It also enhanced chemosensitivity by sensitizing prostate cancer cells to apoptosis through induction of PAWR endorsing its therapeutic potential.  相似文献   
105.
Cytokines play an important role in regulation of immune responses either in health or disease. In the present study, the cDNAs encoding mature Interleukin (IL)-2, interferon gamma (IFN-γ), and IL-12 p35 and p40 of Pashmina goat were cloned and sequenced. The amino acid sequence was deduced from nucleotide sequence and compared with those available in GeneBank. Mature forms of goat IL-2, IFN-γ, IL-12 p35, and IL-12 p40 composed of 135, 143, 196, and 305 amino acid residues, respectively. Comparison of amino acid sequence of goat IL-2 with sheep, buffalo, cattle, pig, camel, cat, and human sequences showed homology percentages of 100, 97.8, 96.3, 72.4, 72.4, 67.2, and 64.7, respectively. Amino acid sequence of goat IFN-γ showed 98.6, 95.8, 81.1, 81.8, 80.4, and 62.9 percent homology with sheep, bovine, pig, horse, dog, and humans, respectively. Homology ranging from 81.6 to 99% for IL-12 p35 sequences and 85.6 to 100% for IL-12 p40 sequences at amino acid level were observed across these species. Multiple sequence alignment and phylogenetic analysis of goat cytokines revealed close relationship with sheep sequence.  相似文献   
106.
The Rosa damascena has organic production and this plant is the most important economic crop in Kerman province. Roses have been used since the earliest times in rituals, cosmetics, perfumes, medicines and aromatherapy. The rose stem sawfly (Hartigia trimaculata) and rose stem girdler (Agrilus aurichalceus) are new and major pests of R. damascena in the Lalehzar region of Kerman province. These pests cause severe damage to plants by feeding stems and new management strategies for their control are continually being investigated. To investigate appropriate biological control agent in the region during 2005–2007, 184 isolates of fungi were collected from these pests. Isolation of fungi was achieved using standard methods. In this study, H. trimaculata and A. aurichalceus from R. damascena for the first time were recorded in Iran. Lecnicillium muscarium from H. trimaculata, L. muscarium from A. aurichalceus, Acremonium kiliense from H. trimaculata, and A. egyptiacum from A. aurichalceus have for the first time been recorded, and L. muscarium has been introduced as a suitable biological agent for control of these pests.  相似文献   
107.
Abstract

Tomato (Solanum lycopersicum L.) plants showing stunting, big bud, leaves yellowing or reddening and witches’-broom symptoms were observed since 2009 in Pakistan. A weed Parthenium hysterophorus grown in and around tomato fields also exhibited witches’-broom like symptoms. Fluorescence light microscopy of hand-cut stem stalk sections treated with Dienes’ stain showed blue areas in the phloem region of both tomato and P. hysterophorus symptomatic plants that indicated the association of phytoplasma with the complex. Amplification of 1.2?kb 16S rDNA fragment in nested PCR confirmed that the symptomatic tomato and P. hysterophorus plants are infected by a phytoplasma. Partial sequencing of 16S rRNA (GenBank accession: LT671581 and LT671583) and virtual restriction fragment length polymorphism confirmed that the phytoplasma associated with both plant species had the greatest homology to 16SrII-D subgroup. Disease was successfully transmitted by grafting and leafhopper Orosius albicinctus in tomato plants. This is the first report of natural occurrence of 16SrII-D phytoplasma in tomatoes and a weed P. hysterophorus in Pakistan.  相似文献   
108.
109.
ABSTRACT: BACKGROUND: Oculocutaneous albinism (OCA) is caused by a group of genetically heterogeneous inherited defects that result in the loss of pigmentation in the eyes, skin and hair. Mutations in the TYR, OCA2, TYRP1 and SLC45A2 genes have been shown to cause isolated OCA. No comprehensive analysis has been conducted to study the spectrum of OCA alleles prevailing in Pakistani albino populations. METHODS: We enrolled 40 large Pakistani families and screened them for OCA genes and a candidate gene, SLC24A5. Protein function effects were evaluated using in silico prediction algorithms and ex vivo studies in human melanocytes. The effects of splice-site mutations were determined using an exon-trapping assay. RESULTS: Screening of the TYR gene revealed four known (p.Arg299His, p.Pro406Leu, p.Gly419Arg, p.Arg278*) and three novel mutations (p.Pro21Leu, p.Cys35Arg, p.Tyr411His) in ten families. Ex vivo studies revealed the retention of an EGFP-tagged mutant (p.Pro21Leu, p.Cys35Arg or p.Tyr411His) tyrosinase in the endoplasmic reticulum (ER) at 37degreesC, but a significant fraction of p.Cys35Arg and p.Tyr411His left the ER in cells grown at a permissive temperature (31degreesC). Three novel (p.Asp486Tyr, p.Leu527Arg, c.1045-15T>G) and two known mutations (p.Pro743Leu, p.Ala787Thr) of OCA2 were found in fourteen families. Exon-trapping assays with a construct containing a novel c.1045-15T>G mutation revealed an error in splicing. No mutation in TYRP1, SLC45A2, and SLC24A5 was found in the remaining 16 families. Clinical evaluation of the families segregating either TYR or OCA2 mutations showed nystagmus, photophobia, and loss of pigmentation in the skin or hair follicles. Most of the affected individuals had grayish-blue colored eyes. CONCLUSIONS: Our results show that ten and fourteen families harbored mutations in the TYR and OCA2 genes, respectively. Our findings, along with the results of previous studies, indicate that the p.Cys35Arg, p.Arg278* and p.Gly419Arg alleles of TYR and the p.Asp486Tyr and c.1045-15T>G alleles of OCA2 are the most common causes of OCA in Pakistani families. To the best of our knowledge, this study represents the first documentation of OCA2 alleles in the Pakistani population. A significant proportion of our cohort did not have mutations in known OCA genes. Overall, our study contributes to the development of genetic testing protocols and genetic counseling for OCA in Pakistani families.  相似文献   
110.
Alzheimer disease (AD) is a complex disorder that involves numerous cellular and subcellular alterations including impairments in mitochondrial homeostasis. To better understand the role of mitochondrial dysfunction in the pathogenesis of AD, we analyzed brains from clinically well-characterized human subjects and from the 3xTg-AD mouse model of AD. We find Aβ and critical components of the γ-secretase complex, presenilin-1, -2, and nicastrin, accumulate in the mitochondria. We used a proteomics approach to identify binding partners and show that heat shock protein 60 (HSP60), a molecular chaperone localized to mitochondria and the plasma membrane, specifically associates with APP. We next generated stable neural cell lines expressing human wild-type or Swedish APP, and provide corroborating in vitro evidence that HSP60 mediates translocation of APP to the mitochondria. Viral-mediated shRNA knockdown of HSP60 attenuates APP and Aβ mislocalization to the mitochondria. Our findings identify a novel interaction between APP and HSP60, which accounts for its translocation to the mitochondria.  相似文献   
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