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More than two consecutive miscarriages in less than 20 weeks of gestation is defined as recurrent spontaneous miscarriage. Various causes such as uterine anatomical anomalies, genetic factors, and infectious and endocrine disorders have been reported for RPL. However, approximately 50% of the causes are unknown, which can be due to male factors. Several studies have been done on semen parameters to determine the unknown causes and risk factors for miscarriages, however, only studying common semen parameters have not been sufficient. In this study, the relationship between sperm DNA fragmentation, the amount of free radicals, and total antioxidant capacity (TAC) in semen have been considered as a risk factor for spontaneous miscarriage. Semen samples were collected from 42 men whose partners had a history of spontaneous miscarriage and 42 fertile men as the control group. Volume, pH, viscosity, concentration, and motility of semen, as well as sperm morphology were measured. Sperm DNA fragmentation was analyzed by the sperm chromatin structure assay (SCSA) and TUNEL methods, the amount of sperm free radicals was measured by the luminescence method and the total amount of semen antioxidant was measured using the TAC kit. The results have shown that sperm motility in the experimental group was significantly less than the control group (P?=?0.001). The percentage of sperm DNA fragmentation and the amount of free radicals in the experimental group were significantly higher than the control group (P?<?0.001). The total amount of antioxidant was lower in the experimental group compared to the control. Spouses of men with lower sperm motility and higher DNA fragmentation had a higher chance of spontaneous miscarriage when compared to the control group. The results of this study support the hypothesis that sperm DNA fragmentation is a major contributor to spontaneous miscarriage.The relationship between SDF, ROS and TAC with RPL. 相似文献
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Refolding of GuHCl-denatured α-amylase was investigated using the artificial chaperone-assisted method. Three different cationic
detergents (CTAB, TTAB and DTAB) and two nonionic detergents (Tween 80 and Triton X-100) were evaluated as the capturing reagents
along with α- and β-CD as the stripping agents. The refolding yields, at a final protein concentration of 0.15 mg/ml, were
82, 71 and 66% in the presence of β-CD and CTAB, TTAB or DTAB, respectively. To improve the refolding yield and to suppress
the extent of aggregation, the initial rate of the stripping step was slowed down by maintaining the refolding environment
at 4°C for about 3 min followed by raising the temperature to 25°C. Under this thermal procedure, the refolding yield and
the extent of aggregation were changed from 82 and 25% at 25°C to 94 and 7% at 4°C, respectively. These findings may assist
the activity recovery of recombinant proteins at relatively high concentrations. 相似文献
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Structure‐function relationships of brazzein variants with altered interactions with the human sweet taste receptor 下载免费PDF全文
Kiran K. Singarapu Marco Tonelli John L. Markley Fariba M. Assadi‐Porter 《Protein science : a publication of the Protein Society》2016,25(3):711-719
Brazzein (Brz) is a small (54 amino acid residue) sweet tasting protein with physical and taste properties superior to other non‐carbohydrate sweeteners. In an investigation of sequence‐dependent functional properties of the protein, we used NMR spectroscopy to determine the three‐dimensional structures and dynamic properties of two Brz variants: one with a single‐site substitution (D40K), which is three‐fold sweeter than wild‐type Brz, and one with a two‐residue insertion between residues 18 and 19 (ins18RI19), which is devoid of sweetness. Although the three‐dimensional folds of the two variants were very similar to wild‐type Brz, they exhibited local conformational and dynamic differences. The D40K substitution abolished the strong inter‐stand H‐bond between the side chains of residues Gln46 and Asp40 present in wild‐type Brz and increased the flexibility of the protein especially at the mutation site. This increased flexibility presumably allows this site to interact more strongly with the G‐protein coupled human sweet receptor. On the other hand, the Arg‐Ile insertion within Loop9–19 leads to distortion of this loop and stiffening of the adjacent site whose flexibility appears to be required for productive interaction with the sweet receptor. 相似文献
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Amir Amiri Yekta Azam Dalman Poopak Eftekhari-Yazdi Mohammad Hossein Sanati Abdol Hossein Shahverdi Rahman Fakheri Hamed Vazirinasab Mohammad Taghi Daneshzadeh Mahdi Vojgani Alireza Zomorodipour Nayeralsadat Fatemi Zeinab Vahabi Shahab Mirshahvaladi Fariba Ataei Elmira Bahraminejad Najmehsadat Masoudi Mojtaba Rezazadeh Valojerdi Hamid Gourabi 《Transgenic research》2013,22(1):131-142
There are growing numbers of recombinant proteins that have been expressed in milk. Thus one can consider the placement of any gene of interest under the control of the regulatory elements of a milk protein gene in a dairy farm animal. Among the transgene introducing techniques, only nuclear transfer (NT) allows 100?% efficiency and bypasses the mosaicism associated with counterpart techniques. In this study, in an attempt to produce a transgenic goat carrying the human coagulation factor IX (hFIX) transgene, goat fetal fibroblasts were electroporated with a linearized marker-free construct in which the transgene was juxtaposed to ??-casein promoter designed to secret the recombinant protein in goat milk. Two different lines of transfected cells were used as donors for NT to enucleated oocytes. Two transgenic goats were liveborn. DNA sequencing of the corresponding transgene locus confirmed authenticity of the cloning procedure and the complementary experiments on the whey demonstrated expression of human factor IX in the milk of transgenic goats. In conclusion, our study has provided the groundwork for a prosperous and promising approach for large-scale production and therapeutic application of hFIX expressed in transgenic goats. 相似文献
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Fariba Mozaffarian 《ZooKeys》2013,(319):231-248
Iran is known as the most complex and varied country in southwest Asia, in terms of geography, vegetation, climate and consequently biological diversity. The rather high number of recorded endemic species of Fulgoromorpha in Iran indicates a high potential for speciation in some areas.In this study, in order to identify the endemic zones for Fulgoromorpha of Iran, three main biogeographic regions of the country were divided into 13 primary zones, mainly according to the distribution of published and unpublished locality records of endemic species. Using Venn diagrams and cluster analyses on the primary zones, 6 final endemic zones were recognized: Caspian zone, southern slopes of Alborz, Zagros Mountains, Kerman Mountains, Khorasan Mountains, and Baluchestan and Persian Gulf coasts. Then a similarity map was produced for endemic zones using a Multidimensional analysis (Alscal) and the differences between the positions of the same zones in the similarity and geographic maps were discussed. 相似文献
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Yusef Omidi Khaniabadi Pierre Sicard Arash Omidi Khaniabadi Shabnam Mohammadinejad Fariba Keishams Afshin Takdastan 《人类与生态风险评估》2019,25(5):1298-1310
In this study, we have estimated the number of total mortality (T-mortality), cardiovascular morbidity (CV-mortality), respiratory mortality (R-mortality), hospital admissions due to cardiovascular diseases (HA-CVD), respiratory diseases (HA-RD), chronic obstructive pulmonary diseases (COPD) and acute myocardial infarction (AMI) due to exposure to particulate matter less than 10 µm (PM10), 2.5 µm (PM2.5) and sulfur dioxide (SO2) in western Iran in 2016. The World Health Organization (WHO) method was used to assess the mortality and morbidity among the exposed people. The results showed that about 3.9% CM (95% CI: 2.9–7.8%), 3.9% HA-RD (95% CI: 2.4–7.8%) and 4.4% HA-CVD (95% CI: 3.0–6.8%) for ambient PM10 and about 7.3% TM (95% CI: 4.2–9.7%), 12.1% CM (95% CI: 3.5–14.6%) and 3.0% RM (95% CI: 0–6.3%) for PM2.5 are respectively attributed to concentrations exceeding 10 µg/m3. Furthermore, 3.2% HA-COPD (95% CI: 0–5.04%) and 4.2% AMI (95% CI: 1.6–4.3%) can be attributed to SO2 concentrations greater than 10 µg/m3, respectively. To reduce the adverse health effect of PM, health advices provided by health authorities should be given to general population especially vulnerable people such as people with chronic lung and heart pathologies, elderly and children during the dusty days. 相似文献
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Ansari N Khodagholi F Ramin M Amini M Irannejad H Dargahi L Amirabad AD 《Neurochemistry international》2010,57(8):958-968
Anti-inflammatory therapy approaches have been in the focus of attention in the treatment of neurodegenerative diseases, such as Alzheimer's disease (AD). In this study, we examined the role of new 1,2,4-triazine derivatives against cytotoxicity exerted by lipopolysaccharide (LPS) in differentiated rat pheochromocytoma (PC12) cell line. Our results indicated that LPS-induced cell death can be inhibited in the presence of some of these compounds, as measured by MTT test, acridine orange/ethidium bromide staining and caspase-3 expression assay. We further showed that these compounds exert their protective effects through the inhibition of LPS-induced generation of nitric oxide and reactive oxygen species. Triazine derivatives inhibited LPS-induced nuclear translocation of nuclear factor- κB, a known regulator of a host of genes involved in specific stress and inflammatory responses. Pretreatment of PC12 cells with triazine derivatives also suppressed LPS-induced cyclooxygenase-2 expression while up-regulated heat shock protein-70 (Hsp-70). Moreover, the treatment of brain diseases is limited by the insufficiency in delivering therapeutic drugs into brain relating to highly limited transport of compounds through blood-brain barrier (BBB). Using a reliable model based on the artificial neural network, we indicated that these compounds are capable of penetrating BBB and may be useful agents for preventing neuroinflammatory diseases like AD. 相似文献