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231.
232.
Background:Treatment with BMMSCs has anti-inflammatory, tissue regenerative, angiogenic, and immune-stimulating effects. When using as sheets or accumulate, BMMSCs causes the development of neoangiogenesis in damaged skin tissue. Diabetes, a metabolic disorder, can negatively affect many physiological functions, including the process of skin injury repair. This adverse impact may increase the risk of skin surgery. RSF is commonly used in reconstructive surgery. The terminal part of the RSF is often affected by necrosis because of impaired blood flow, which is exacerbated in diabetes. This study investigated the effect of stem cells, applied as accumulated or cell sheets, along with RSF surgery on skin capillaries in STZ-induced diabetic rats. Methods:Thirty male Wistar rats were divided into three groups (n = 10): diabetes-RSF control, diabetes-RSF local applied stem cells (loc-BMMSCs), diabetes-RSF applied stem cells as accumulated or cell sheets (ac-BMMSCs). Two weeks after the STZ injection, RSF surgery and stem cell therapy (6 × 109) were carried out (day zero). Furthermore, stereological methods were used to investigate the capillary patterns among the groups. Anti-CD31/PCAM1 immunohistochemistry was also used for further confirmation of changes in capillary parameters. Results:The results demonstrated that capillaries were protected by MSC sheets in the flap tissue, and the thickness of the epidermal layer was improved, indicationg the possible beneficial effects of MSC sheets on diabetic wound treatment. Conclusion:Stem cells, as ac-BMMSCs, may decrease the levels of wound healing complications in diabetes and can be considered as a cell therapy option in such conditions.Key Words: Neoangiogenesis, Skin flap, Transplantation, Wound healing 相似文献
233.
Mehdi Alikhani Samaneh Saberi Maryam Esmaeili Valrie Michel Mohammad Tashakoripour Afshin Abdirad Arezoo Aghakhani Sana Eybpoosh Massoud Vosough Mohammad Ali Mohagheghi Mahmoud Eshagh Hosseini Eliette Touati Marjan Mohammadi 《Iranian Biomedical Journal》2021,25(5):323
Background:Variations in mtDNA-CN of PBLs, as a potential biomarker for GC screening has currently been subject to controversy. Herein, we have assessed its efficiency in GC screening, in parallel and in combination with sPG I/II ratio, as an established indicator of gastric atrophy. Methods:The study population included GC (n = 53) and non-GC (n = 207) dyspeptic patients. The non-GC group was histologically categorized into CG (n = 104) and NM (n = 103) subgroups. The MtDNA-CN of PBLs was measured by quantitative real-time PCR. The sPG I and II levels and anti-H. pylori serum IgG were measured by ELISA. Results:The mtDNA-CN was found significantly higher in GC vs. non-GC (OR = 3.0; 95% CI = 1.4, 6.4) subjects. Conversely, GC patients had significantly lower sPG I/II ratio than the non-GC (OR = 3.2; CI = 1.4, 7.2) subjects. The combination of these two biomarkers yielded a dramatic amplification of the odds of GC risk in double-positive (high mtDNA-CN-low sPGI/II) subjects, in reference to double-negatives (low mtDNA-CN-high sPGI/II), when assessed against non-GC (OR = 27.1; CI = 5.0, 147.3), CG (OR = 13.1; CI = 2.4, 72.6), or NM (OR = 49.5; CI = 7.9, 311.6) groups. Conclusion:The combination of these two biomarkers, namely mtDNA-CN in PBLs and serum PG I/II ratio, drastically enhanced the efficiency of GC risk assessment, which calls for further validations. Key Words: Biomarkers, DNA copy number variation, Mitochondrial DNA, Stomach neoplasms 相似文献
234.
Maryam Shekari Kayvan Etebari Abdolahad Shadparvar 《Pesticide biochemistry and physiology》2008,91(1):66-74
Methanolic extract of Artemisia annua L., a weed collected around paddy fields in north of Iran, was investigated for its toxic effects on: feeding, growth, fecundity, fertility including the biochemical characteristics of elm leaf beetle Xanthogaleruca luteola Mull. The toxicity tests indicate that insecticidal effect was 2.4-fold higher in 3rd instar larvae than in adults. The LC50 was 48% and 43.77% of a methanolic leaf extract at 24 and 48 h, respectively. The feeding deterrence was highest at 10% concentration and lowest at 0.625% for 3rd instar larvae and adults during the first 24 h and decreased thereafter. Larval duration significantly increased at higher concentrations. Larval treatment with 10% methanolic extract resulted in deformed adults (adultoids) with drastic changes in gross morphology of female reproductive system. Food digestion and assimilation significantly decreased in adults. Larval duration and adult fecundity and fertility were also significantly reduced. Twenty-four hours after treating 3rd instar larva with the extract the levels of glucose, protein, urea, uric acid, α-amylase, alkaline phosphatase, alanine amino transferase and aspartate amino transferase significantly changed. However, at 48 h the extract lost its potency. The extract did not effect the level of cholesterol in treated larva. These results indicate that Artemisia annua L. extract contains inhibitors of key metabolic pathways that may be useful in future control of the elm leaf beetle. 相似文献
235.
Maryam Akbari Hessam Jafari Mojtaba Rostami Gholam Reza Mahdavinia Ali Sobhani nasab Dmitry Tsurkan Iaroslav Petrenko Mohammad Reza Ganjali Mehdi Rahimi-Nasrabadi Hermann Ehrlich 《Marine drugs》2021,19(9)
The renewable, proteinaceous, marine biopolymer spongin is yet the focus of modern research. The preparation of a magnetic three-dimensional (3D) spongin scaffold with nano-sized Fe3O4 cores is reported here for the first time. The formation of this magnetic spongin–Fe3O4 composite was characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential thermal analysis (DTA) (TGA-DTA), vibrating sample magnetometer (VSM), Fourier-transform infrared spectroscopy (FTIR), and zeta potential analyses. Field emission scanning electron microscopy (FE-SEM) confirmed the formation of well-dispersed spherical nanoparticles tightly bound to the spongin scaffold. The magnetic spongin–Fe3O4 composite showed significant removal efficiency for two cationic dyes (i.e., crystal violet (CV) and methylene blue (MB)). Adsorption experiments revealed that the prepared material is a fast, high-capacity (77 mg/g), yet selective adsorbent for MB. This behavior was attributed to the creation of strong electrostatic interactions between the spongin–Fe3O4 and MB or CV, which was reflected by adsorption mechanism evaluations. The adsorption of MB and CV was found to be a function of pH, with maximum removal performance being observed over a wide pH range (pH = 5.5–11). In this work, we combined Fe3O4 nanoparticles and spongin scaffold properties into one unique composite, named magnetic spongin scaffold, in our attempt to create a sustainable absorbent for organic wastewater treatment. The appropriative mechanism of adsorption of the cationic dyes on a magnetic 3D spongin scaffold is proposed. Removal of organic dyes and other contaminants is essential to ensure healthy water and prevent various diseases. On the other hand, in many cases, dyes are used as models to demonstrate the adsorption properties of nanostructures. Due to the good absorption properties of magnetic spongin, it can be proposed as a green and uncomplicated adsorbent for the removal of different organic contaminants and, furthermore, as a carrier in drug delivery applications. 相似文献
236.
In this study, the effects of enzymes on wool yarn in the presence of different salts (ammonium sulfate, sodium tetraborate,
and di-sodium hydrogen phosphate) were investigated. Alcalase 2,5 LDX and Savinase 16 LEX were selected as proteolytic enzymes.
In addition, the effects of surfactants (Sandozin NRW, Irgasol NA, Erkantol NR, and Sandozin EH) on the enzyme treatment of
wool yarn were evaluated. The results indicated that the effects of enzymes on wool yarn were greatest in the presence of
sodium tetraborate. Furthermore, the properties of wool yarn such as weight loss, strength loss, and hairiness were influenced
by these surfactants. The SEM images of the treated samples confirmed the obtained results. 相似文献
237.
Maryam Azadbar Akram Ranjbar Azadeh Hosseini-Tabatabaei Abolfazl Golestani Maryam Baeeri Mohammad Sharifzadeh Mohammad Abdollahi 《Pesticide biochemistry and physiology》2009,95(3):121-125
The main objective of this study was to investigate the possible protective effect of pentoxifylline as a phosphodiesterase 5 inhibitor used as a cardiovascular medication on malathion-induced changes on rat mitochondrial-bound hexokinase activity.Animals in four various groups received moderate toxic dose of malathion (200 mg/kg/day), effective dose of pentoxifylline (50 mg/kg/day) alone and in combination, and the control group that received only vehicle. All administrations were done intraperitoneally for one week. At the end of the experiment, the brain was removed and the mitochondria were isolated. Hexokinase (HK) activity, cellular lipid peroxidation (LPO) and total antioxidant capacity (TAC) were analyzed in brain mitochondria.Malathion noticeably decreased TAC and increased HK activity and LPO in the mitochondria whereas pentoxifylline significantly restored malathion-induced changes in LPO, HK, and TAC.The results of the present study indicate that phosphodiesterase 5 inhibition remarkably protects brain mitochondria from malathion-induced changes on HK activity and oxidative stress. 相似文献
238.
Background: The effect of ovariectomy and accompanying sudden loss of circulating gonad hormones on spatial learning performance in the young adult rats was examined. We hypothesized that spatial learning and memory in a considerable number of women who undergo a surgical menopause and estrogen deprivation before their natural menopause be impaired. Methods: In this study, we used 26 Wistar rats (approximately five months of age) and divided them into two groups: intact and ovariectomized (OVX). They were tested for spatial reference memory in Morris water maze 6 weeks after OVX. Results: The results showed that the performance of OVX group in the water maze was significantly lower than the control group. Although, mean path length decreased across blocks in both groups, OVX rats had significantly longer path length than controls across blocks 2-6 (P<0.05). OVX rats had lower percent of total time spent in target quarter than controls in probe trials (P<0.05). Body weight gain was significant only in OVX group during the experiment (P<0.05). Plasma estrogen significantly decreased after OVX (P<0.05). Conclusion: This finding provides further evidence for the role of estrogen, a gonadal steroid hormone, in the manipulation of functions related to learning and memory. It is suggested that estrogen loss following OVX impaired spatial reference memory in young adult rats. Our results suggest that it is necessary to protect women who undergo a surgical menopause before their natural menopause from cognition impairments. 相似文献
239.
Afshar S Heidari R Farshid AA Ilkhanipour M 《Pakistan journal of biological sciences: PJBS》2008,11(13):1742-1745
The aim of this study was to evaluate the effects of acute exposure to various doses of fenitrothion (FNT) on level of serum glucose, total protein, triglycerides (TG), total cholesterol (TC) and some hematological parameters. The study was conducted on 8-week-old male Wistar rats that divided into four groups (three experimental groups and one control group), were treated orally with different doses (25, 50 and 100 mg kg(-1)) of fenitrothion for 28 consecutive day. After treatment, blood samples were collected for biochemical and hematological studies. Present results demonstrated that exposed groups led to significant dose-dependent increase in serum glucose and cholesterol levels. Significant decrease was observed in some hematological parameters [Red Blood Cell (RBC) counts, Hemoglobin (Hb), Haematocrite (Ht) and Mean Corpuscular Hemoglobin (MCH) values]. Serum total protein and triglycerides were also decreased not significantly in exposed groups when compared with control. Generally, the degrees of observed variations were found to be dose dependent. 相似文献
240.
Naseri MK Naseri ZG Mohammadian M Birgani MO 《Pakistan journal of biological sciences: PJBS》2008,11(12):1594-1599
The effect of Mentha longifolia (L.) leaf hydroalcoholic extract (MLE) was examined on rat ileal smooth muscle contractions. Last portion of ileum from male adult Wistar rat was mounted in an organ bath containing Tyrode solution. The tissue was contracted by carbachol (CCh, 10 microM), KCl (60 mM) and BaC12 (4 mM) and then MLE (0.0625-1 mg mL(-1)) was added to the bath cumulatively. The effect of MLE on KCl-induced contraction was examined after tissue incubation with propranolol (1 microM), naloxone (1 microM) and N omega-nitro-L-arginine methyl ester (L-NAME, 100 microM). The effect of MLE on CaCl2-induced ileal contraction in Ca(2+)-free with high potassium Tyrode solution was also evaluated. The role of potassium channels was examined by ileum incubation (5 mim) with tetraethylammonium (TEA, 1 mM). The results showed that KCl-, CCh and BaCl2-induced ileal contractions were inhibited (p < 0.001) by cumulative concentrations of MLE with the same potency. In addition, MLE (0.25-1 mg mL(-1)) inhibited (p < 0.01) ileal contractions induced by CaCl2 (0.45-2.7 mM) in a concentration-related manner. The antispasmodic effect of MLE was affected neither by propranolol, L-NAME nor by naloxone. The MLE concentration-response curve was shifted to the right (p < 0.05) by tissue incubation with TEA. From results it may be suggested that Mentha longifolia hydroalcoholic leaf extract induces its spasmolytic activity mainly through disturbance in calcium mobilization and partly by potassium channels activation. Present results show that Mentha longifolia leaf extract exerts relaxant effects on intestinal smooth muscle, consistent with the traditional use of the plant to treat gastrointestinal disorders such as diarrhea and colic. 相似文献