Axonal myelination is an essential process for normal functioning of the vertebrate central nervous system. Proper formation of myelin sheaths around axons depends on the timely differentiation of oligodendrocytes. Th...Axonal myelination is an essential process for normal functioning of the vertebrate central nervous system. Proper formation of myelin sheaths around axons depends on the timely differentiation of oligodendrocytes. This differentiation occurs on a predictable schedule both in culture and during development. However, the timing mechanisms for oligodendrocyte differentiation during normal development have not been fully uncovered. Recent studies have identified a large number of regulatory factors, including cell-intrinsic factors and extracel- lular signals, that could control the timing of oligodendrocyte differentiation. Here we provide a mechanistic and critical review of the timing control of oligodendrocyte differentiation.展开更多
Western Liaoning of northeastern China is world-renowned for the MesozoicJehol biota, especially for yielding many feathered dinosaurs, primitive birds, mammals and fossilangiosperm. This paper describes a complete sp...Western Liaoning of northeastern China is world-renowned for the MesozoicJehol biota, especially for yielding many feathered dinosaurs, primitive birds, mammals and fossilangiosperm. This paper describes a complete specimen of a symmetrodont mammal with well-preservedhairs and soft tissue from the basal part of the Yixian Formation in the Sihetun area, Beipiao,western Liaoning. It is significant for understanding the morphology, osteology, phylogeny and lifehabits of Mesozoic symmetrodont mammals.展开更多
A new stegosaur species, Jiangjunosaurusjunggarensis, gen. et sp. nov., is erected based on a specimen collected from the Upper Jurassic upper section of the Shishugou Formation in the Junggar Basin, Xinjiang, China. ...A new stegosaur species, Jiangjunosaurusjunggarensis, gen. et sp. nov., is erected based on a specimen collected from the Upper Jurassic upper section of the Shishugou Formation in the Junggar Basin, Xinjiang, China. It represents the first stegosaur from the Jurassic of Xinjiang and increases the diversity of the dinosaur fauna in the Shishugou Formation. The new genus is characterized by symmetrical and proportionally wide tooth crowns, a sub-rectangular axial neural spine seen in lateral view, and large openings on the lateral surfaces of the cervical centra. A preliminary character analysis suggests that this new taxon is more derived than the Middle Jurassic stegosaur Huayangosaurus but more primitive than most other known stegosaur species.展开更多
Dear Editor, Although various components of the Wnt/β-catenin pathway have been investigated, there are conflicting reports on the roles of Wnt/β-catenin signaling in oligodendrogenesis and differentiation. For inst...Dear Editor, Although various components of the Wnt/β-catenin pathway have been investigated, there are conflicting reports on the roles of Wnt/β-catenin signaling in oligodendrogenesis and differentiation. For instance, the △Exon3 mutation of β-catenin[14], which stabilizes β-catenin by deletion of the phosphorylation site for the destruction complex, significantly inhibits the differentiation of oligodendrocytes, but knockout of β-catenin also delays it.展开更多
Background:Testicular torsion(TT)is an acute inflammatory process leading to male infertility.Today,anti-i nflammatory effects of exosomes derived from blood serum are used in various laboratory procedures.In the pres...Background:Testicular torsion(TT)is an acute inflammatory process leading to male infertility.Today,anti-i nflammatory effects of exosomes derived from blood serum are used in various laboratory procedures.In the present study,the anti-i nflammatory effects of blood-serum-derived exosomes in treatment of acute inflammation following TT in mice were evaluated.Materials and Methods:Eighteen male mice were grouped as healthy control,TT,and TT+exosome.TT was induced surgically,and exosomes were extracted from blood serum and administrated by a single intratesticular injection(10 IU).Malondialdehyde(MDA)and Griess assays were used to evaluate the level of oxidative stress.Sperm indices,testosterone(Tes),and apoptotic gene expression(p-53,Bcl2,and Caspase-3)were also assessed.H&E and immunohistochemistry(IHC)stainings were used for histopathological investigations.Data analysis was applied by SPSS(v.19)software.Results:Oxidative stress and apoptotic genes expression were increased significantly(p<0.05)in TT group compared with control.Sperm parameters and Tes were significantly increased,and expression of apoptotic genes was significantly reduced in TT+exosome group(p<0.05).Conclusion:Since the blood-serum-derived exosomes have anti-i nflammatory features,the intratesticular application of blood-serum-derived exosomes can be used clinically in acute phase of orchitis following TT to inhibit testicular inflammation.展开更多
Objective:To study the role of Quercetin in streptozotocin-induced diabetes in rals.Methods:Wistar male rat(n=40) were allocated into three groups,control group(n=10) and Quercetin(QR) group received 15 mg/kg(IP) QR.(...Objective:To study the role of Quercetin in streptozotocin-induced diabetes in rals.Methods:Wistar male rat(n=40) were allocated into three groups,control group(n=10) and Quercetin(QR) group received 15 mg/kg(IP) QR.(n=10),and diabetic group that received 55 mg/kg(IP)streptozotocin(STZ)(n=20) which was subdivided to two groups of 10;STZ group and treatment group.Treatment group received 55mg/kg(IP) STZ plus 15 nig/kg QR,daily lor 4 weeks,respectively:however,the control group just received an equal volume of distilled water dailv(IP).Diabetes was induced by a single(IP) injection of streptozotocin(55 mg/kg).Animal-were kept in standard condition.Twenty-eight days after inducing diabetic,5 mL blood were collected for TAC,MPA and Ox-LDL levels and liver tissues of rat in whole groups were removed then prepared for apoptosis analysis by Tunel method.Results:Apoptotic cells significantly decreased in group that has received 15 mg/kg(IP) Quercetin(P<0.05) in comparison to experimental groups(P<0.05).Conclusions:Since in our study 15 nig/kg(IP) Quercetin have significantly Preventive ellecl on liver cells damages by reducing number of apoptotic cells in Liver,so it seems that using it can be effective for treatment in diabetic rat.展开更多
Background:Endometriosis can lead to infertility.Since there is no definitive treat-ment for endometriosis,animal modelling seems necessary to examine the possible treatments.Mouse endometrium cannot be separated for ...Background:Endometriosis can lead to infertility.Since there is no definitive treat-ment for endometriosis,animal modelling seems necessary to examine the possible treatments.Mouse endometrium cannot be separated for endometriosis induc-tion.In addition,transplantation of uterus into the abdominal viscera to induce endometriosis causes organ damage.In this study,we defined a new model of en-dometriosis leading to separability of endometrium and a safe anatomical region for transplantation.Methods:Forty female mice were allocated to 5 groups:1,sham;2,allograft uterus transplantation of mice to anterior abdominal wall of mice;3,allograft uterus trans-plantation of mice to mesentery of mice;4,xenograft endometrial transplantation of rat to anterior abdominal wall of mice;5,xenograft endometrial transplantation of rat to mesentery of mice.Adult female rats with a previous pregnancy experience were selected and placed in the vicinity of male rats for 2 weeks to induce estrogen secre-tion and increase endometrial thickness.Results:In the 4th group of animals,compared to sham,the peritoneal concentrations of VEGF-A,TNF-α,NO,MDA,and serum levels of CA-125 and IL-37 were increased and total body weight was decreased,while weight and size of endometrial lesions were increased significantly(P<.05).Genes expression of HOXA10 and HOXA11 were decreased significantly(P<.05)in groups 2 and 4 compared to sham.Conclusions:Xenograft transplantation of endometrium from rat to anterior abdomi-nal wall of mice can potentially mimic human endometriosis morphologically,histo-logically,and genetically.展开更多
Objective: To evaluate the impact of Olea (O.) europaea extract on markers of oxidative stress and apoptosis of ovarian tissues in a rat model of torsion/detorsion-induced ovarian damage. Methods: A total of 28 Wistar...Objective: To evaluate the impact of Olea (O.) europaea extract on markers of oxidative stress and apoptosis of ovarian tissues in a rat model of torsion/detorsion-induced ovarian damage. Methods: A total of 28 Wistar female rats were randomly assigned into 4 groups, with 7 rats in each group. The sham group received a 2.5 cm longitudinal incision in the midline part of the abdomen which was then sutured with 5-0 nylon thread;the torsion/detorsion group underwent torsion induction for 3 h followed by reperfusion for 10 days;the torsion/detorsion+O. europaea group received 300 mg/kg hydro-alcoholic extract of O. europaea 30 min before detorsion, followed by reperfusion for 10 days;and the O. europaea group only received 300 mg/kg hydro-alcoholic extract of O. europaea for 10 days. After the treatment period, blood samples were taken;the levels of estrogen, glutathione peroxidase, superoxide dismutase, and malondialdehyde were assayed. The histological changes, as well as the rate of apoptosis in ovarian tissues, were also carried out by histomorphometric analysis at day 10 post-procedure. Results: Histological comparisons demonstrated a significant detrimental change in the torsion/detorsion group as compared with other groups. The number of pre-antral and antral follicles and corpus luteum was significantly decreased in the torsion/detorsion group compared with the sham group, while treatment with O. europaea could enhance their numbers (P<0.05). The index of apoptosis and the number of atretic body in the ovarian tissue were significantly higher in the torsion/detorsion group compared with the sham group (P<0.05). The concentrations of glutathione peroxidase, estrogen, and superoxide dismutase as well as the mRNA expression of Bcl-2 were considerably diminished in the torsion/detorsion group while they were elevated in the torsion/detorsion+O. europaea group (P<0.05) compared with the torsion/detorsion group. The serum malondialdehyde level and the mRNA expression of Bax were markedly increased during ischemia, while treatment with O. europaea significantly diminished the increased concentrations of malondialdehyde and Bax level in the torsion/detorsion+O. europaea group (P<0.05). Conclusions: O. europaea extract can reduce the degree of tissue damage induced by oxidative stress and apoptosis in the ovary following ovarian ischemia/reperfusion.展开更多
Oligodendrocytes（OLs） are myelinating glial cells that form myelin sheaths around axons to ensure rapid and focal conduction of action potentials. Here, we found that an axonal outgrowth regulatory molecule, AATYK（...Oligodendrocytes（OLs） are myelinating glial cells that form myelin sheaths around axons to ensure rapid and focal conduction of action potentials. Here, we found that an axonal outgrowth regulatory molecule, AATYK（apoptosis-associated tyrosine kinase）, was up-regulated with OL differentiation and remyelination. We therefore studied its role in OL differentiation. The results showed that AATYK knockdown inhibited OL differentiation and the expression of myelin genes in vitro. Moreover, AATYKdeficiency maintained the proliferation status of OLs but did not affect their survival. Thus, AATYK is essential for the differentiation of OLs.展开更多
Oligodendrocytes（OLs） are glial cells that form myelin sheaths around axons in the central nervous system（CNS）.Loss of the myelin sheath in demyelinating and neurodegenerative diseases can lead to severe impairmen...Oligodendrocytes（OLs） are glial cells that form myelin sheaths around axons in the central nervous system（CNS）.Loss of the myelin sheath in demyelinating and neurodegenerative diseases can lead to severe impairment of movement.Understanding the extracellular signals and intracellular factors that regulate OL differentiation and myelination during development can help to develop novel strategies for enhancing myelin repair in neurological disorders.Here,we report that TAPP1 was selectively expressed in differentiating OL precursor cells（OPCs）.TAPP1 knockdown promoted OL differentiation and myelin gene expression in culture.Conversely,over-expression of TAPP1 in immature OPCs suppressed their differentiation.Moreover,TAPP1 inhibition in OPCs altered the expression of Erk1/2 but not AKT.Taken together,our results identify TAPP1 as an important negative regulator of OPC differentiation through the Mek/Erk signaling pathway.展开更多
BACKGROUND： Lead has caused widespread pollution in the environment due to the numerous industrial applications. One principle target for lead in the human body is the central nervous system However, research has dem...BACKGROUND： Lead has caused widespread pollution in the environment due to the numerous industrial applications. One principle target for lead in the human body is the central nervous system However, research has demonstrated that neurotoxic effects of lead can be ameliorated by antioxidant agents, such as vitamin C. OBJECTIVE： To investigate the protective effects of vitamin C supplementation against lead-induced apoptosis in the adult rat hippocampus, as well as changes in pro-apoptotic protein Bax expression. DESIGN, TIME AND SETTING： A randomized, controlled, animal study was performed at the College of Medicine, Iran University of Medical Sciences from December 2007 to April 2009. MATERIALS： Lead acetate and vitamin C were purchased from Sigma, USA. METHODS： Thirty male rats were randomly assigned to three groups, with 10 rats in each group： control, lead, and lead ＋ vitamin C. Rats from the lead group received intraperitoneal administration of lead 20 mg/kg per day for 7 days. Rats from the lead ＋ vitamin C group received ascorbic acid 500 mg/kg per day in addition to lead acetate （as per the lead group）. MAIN OUTCOME MEASURES： After 7 days of vitamin C administration, hippocampal cell apoptosis was observed using uranyl acetate and lead citrate stainings, hippocampal Bax protein expression was detected by Western blot analysis, and blood lead levels were measured by atomic absorption spectrometry. RESULTS： Vitamin C supplementation significantly reduced lead-induced hippocampal cell apoptosis and decreased hippocampal Bax protein expression. However, vitamin C treatment did not significantly decrease blood lead levels. CONCLUSION： Vitamin C significantly decreased Bax expression and reduced lead-induced hippocampal cell apoptosis.展开更多
The ex-copula penile dorsiflexion reflex(PDFR)is an established measure of sexual dysfunction in male rat models of spinal cord injury.Although the PDFR after complete spinal transection is well described,information ...The ex-copula penile dorsiflexion reflex(PDFR)is an established measure of sexual dysfunction in male rat models of spinal cord injury.Although the PDFR after complete spinal transection is well described,information regarding the more clinically relevant incomplete spinal contusion injury model is limited.This study examined,using two-dimensional(2D)kinematic analysis,the relationship between the PDFR and degree of white matter sparing(WMS).Male Wistar rats received a T9 contusion with varying degrees of impactor forces.Weekly kinematic recordings of the PDFR were made 3-8 weeks postinjury.Sexual reflex components examined included maximum angle of penile dorsiflexion,total penile event duration,and penile ascent speed.Post hoc comparison between animals grouped based upon injury severity(moderate-severe:13.33%-17.15%WMS vs moderate:20.85%-33.50%WMS)ndicated PDFR effects.Specifically,the numbers of animals with more moderate contusions having data points above the median n both maximum angle of penile dorsiflexion and penile ascent speed were significantly lower than animals with more severe njuries.Total penile event duration was also affected but only at more chronic time points(6-8 weeks).Thus,2D kinematic analysis of the PDFR allows for more consistent and quantifiable analysis of the subtle differences that can occur between injury severity groups in the rat contusion model.展开更多
Objective: To evaluate effect of Phaseolus vulgaris (P. vulgaris) on the breastfeeding in female rats. Methods: This experimental study was done from May 2018 to December 2018 in the Anatomical Department of Medical S...Objective: To evaluate effect of Phaseolus vulgaris (P. vulgaris) on the breastfeeding in female rats. Methods: This experimental study was done from May 2018 to December 2018 in the Anatomical Department of Medical School in Kermanshah University of Medical Sciences in Iran. In this study, after one-week adaptation and fertilization by male, 40 female rats within 20 days of pregnancy (on average, every mother had 10 newborns) were equally separated into four groups (animals were administrated after delivery of offspring). Group 1 was control group receiving normal saline interaperitoneally, and groups 2, 3, 4 were treatment groups receiving the dose of 20, 50, 100 mg/kg of P. vulgaris interaperitoneally respectively once a day for 60 days. The prolactin hormone was measured by radio immune assay, number and diameter of alveoli via histological and morphometrical examinations, and receptor prolactin gene expression by real-time polymerase chain reaction method. Results: P. vulgaris significantly improved alveoli's number and diameter, prolactin hormone and receptor prolactin expression when compared to the control group (P<0.001). Conclusions: P. vulgaris is helpful to improve the breastfeeding parameters of rats' mammary glands.展开更多
Liver injury in the setting of human immunodeficiency virus(HIV) infection is more commonly attributed to viral hepatitis or highly active antiretroviral treatment(HAART) toxicity. The severity of liver injury is an i...Liver injury in the setting of human immunodeficiency virus(HIV) infection is more commonly attributed to viral hepatitis or highly active antiretroviral treatment(HAART) toxicity. The severity of liver injury is an important cause of morbidity and mortality. The emergence of autoimmune diseases, particularly autoimmune hepatitis(AIH) in the setting of HIV infection, is rare. Previous reports indicate that elevated liver enzymes are a common denominator amongst these patients. We present two patients with HIV infection, on HAART, with virological suppression. Both patients presented with elevated liver enzymes, and following liver biopsies, were diagnosed with AIH. The clinical course of these patients underscore the therapeutic value of corticosteroids, and in some cases, addition of immunosuppression for AIH treatment.展开更多
Nitric oxide(NO),a member of the reactive nitrogen species family,plays a role in several physiologic processes,including vasculogenesis and angiogenesis,growth and puberty,and senescence and apoptosis.NO plays an imp...Nitric oxide(NO),a member of the reactive nitrogen species family,plays a role in several physiologic processes,including vasculogenesis and angiogenesis,growth and puberty,and senescence and apoptosis.NO plays an important role in the production of ovarian steroids,ovulation,and follicular apoptosis.In other words,increased activity of nitric oxide synthase(NOS)leads to an increased amount of NO,which triggers production of prostaglandins and inflammatory cascades which facilitate follicular rupture and atresia.NO concentration elevation inhibits steroid synthesis in luteal and granulosa cells.Since NO is a major paracrine mediator of various biological processes,as well as a key factor in both the reproductive cycle and embryo implantation,oversynthesis of NO in the uterus results in toxicity and inflammation in epithelial cells and immunorejection of implantation.In the male physiological system,NO synthesized by NOS plays a major role in erectile function and androgen secretion,as well as semen parameters,and oocyte junction to the sperm.Furthermore,this supposedly simple molecule is involved in a number of other functions,such as germ cell evolution,connections between sertoli cells and germ cells in the blood-testis barrier,homodynamic contraction,and germ cell apoptosis.Moreover,NO is considered a key factor in male fertility due to its widespread distribution in both normal and diseased testis tissue.The difference of expression level of NOS in normal and pathological states is a probable cause of fertility destructive processes.展开更多
Because of increased need to tissue and organ transplantation, tissue engineering (TE) researches have significantly increased in recent years in Iran. The present study explored briefly the advances in the TE approac...Because of increased need to tissue and organ transplantation, tissue engineering (TE) researches have significantly increased in recent years in Iran. The present study explored briefly the advances in the TE approaches in Iran. Through comprehensive search, we explored main TE components researches include cell, scaffold, growth factor and bioreactor conducted in Iran. The field of TE and regenerative medicine in Iran dates back to the early part of the 1990 decade and the advent of stem cell researches. During past two decades, Iran was one of leader in stem cell research in Middle East. The next major step in TE was application and fabrication of scaffolds for TE in the early 2000s with focused on engineering bone and nerve tissue. Iranian researchers extensively used natural scaffolds in their studies and hybridized natural polymers and inorganic scaffolds. There are many universities and government research institutes are conducting active research on tissue-engineering technologies. Limitations to TE in Iran include property design and validation of bioreactors. In conclusion, in the last few years, fields of tissue engineering and regenerative medicine such as stem cell technology and scaffolds have progressed in Iran, but one of the biggest challenges for TE is bioreactors researches.展开更多
Exponentially growing cultures of human bladder tumor cells (RT4 and T24) were treated with Vitamin C (VC) alone, Vitamin K3 (VK3) alone, or with a VC:VK3 combination continuously for 5 days or treated with vitamins f...Exponentially growing cultures of human bladder tumor cells (RT4 and T24) were treated with Vitamin C (VC) alone, Vitamin K3 (VK3) alone, or with a VC:VK3 combination continuously for 5 days or treated with vitamins for 1 h, washed with PBS and then incubated in culture medium for 5 days. Co-administration of the vitamins enhanced the antitumor activity 12- to 24-fold for the RT-4 cells and 6- to 41-fold for the T24 cells. Flow cytometry of RT4 cells exposed to the vitamins revealed a growth arrested population and a population undergoing cell death. Growth arrested cells were blocked near the G0/G1-S-phase interface, while cell death was due to autoschizis. Catalase treatment abrogated both cell cycle arrest and cell death which implicated hydrogen peroxide (H2O2) in these processes. The H2O2 production resulted in a moderate increase in lipid peroxidation and depletion of cell thiol levels. Analysis of cellular ATP levels revealed a transient increase in ATP production for VC and the VC:VK3 combination, but decreased ATP levels following VK3 treatment. Lipid peroxidation, thiol depletion and ATP modulation occurred at a 17-fold lower concentration in the vitamin combination than with either vitamin alone. These results suggested that the increased cytotoxicity of the vitamin combination was due to redox cycling and increased oxidative stress.展开更多
Pectus excavatum (PE) and pectus carinatum (PC) are relatively common deformities involving the anterior chest wall, occurring in 1:1000 and 1:1500 live births, respectively. While the etiology remains an enigma, the ...Pectus excavatum (PE) and pectus carinatum (PC) are relatively common deformities involving the anterior chest wall, occurring in 1:1000 and 1:1500 live births, respectively. While the etiology remains an enigma, the association of pectus deformities with other skeletal abnormalities suggests that connective tissue disease may play a role in their pathogenesis. Clinical features of these deformities vary with severity, as determined by the Haller index and Backer ratio, but frequently include cardiac and respiratory abnormalities. Importantly, there exist profound psychosocial implications for children afflicted with these defofrmities, including but not limited to feelings of embarrassment and maladaptive social behaviors. These debilitating characteristics have prompted the development of novel medical and surgical corrective techniques. The correction of pectus deformities reduces the incidence of physiological complications secondary to chest wall malformation, while simultaneously improving body image and psychosocial development in the affected pediatric population. The Ravitch (open) and Nuss (minimally invasive) procedures remain the most frequently employed methods of pectus deformity repair, with no difference in overall complication rates, though individual complication rates vary with treatment. The Nuss procedure is associated with a higher rate of recurrence due to bar migration, hemothorax, and pneumothorax. Postoperative pain management is markedly more difficult in patients who have undergone Nuss repair. Patients undergoing the Ravitch procedure require less postoperative analgesia, but have longer operation times and a larger surgical scar. The cosmetic results of the Nuss procedure and its minimally invasive nature make it preferable to the Ravitch repair. Newer treatment modalities, including the vacuum bell, magnetic mini-mover procedure (3MP), and dynamic compression bracing (DCB) appear promising, and may ultimately provide effective methods of noninvasive repair. However, these modalities suffer from a lack of extensive published evidence, and the limited number of studies currently published fail to adequately define their long-term effectiveness.展开更多
We report combination of explants and enzymatic protocol as mixed enzymatic-explant procedure to faster extraction of MSCs from WJ. Umbilical cords (UC) were collected from Imam Khomini Hospital. For explant outgrowth...We report combination of explants and enzymatic protocol as mixed enzymatic-explant procedure to faster extraction of MSCs from WJ. Umbilical cords (UC) were collected from Imam Khomini Hospital. For explant outgrowth, 6 - 9 pieces of WJ were transferred onto tissue culture flask and waited for attachment. For mixed enzymatic-explant, 1 cm3 pieces WJ were placed in enzymatic cocktail comprising 4 mg/ml Collagenase Type I and 1 mg/ml Hyaluronidase and 0.1% trypsin-EDTA. Then isolated cells were analyzed for surface cell markers such as CD73, CD31. Isolated 1.0 × 106 MSCs/ml were encapsulated in alginate hydrogel. Cells with MSCs phenotype were isolated from mixed enzymatic-explant and explant procedures within 24 - 48 hrs and 7 - 10 days, respectively. Both of procedures were shown to form clumps and colonies with dense centers. Phenotypic changes gradually appeared as round cell in UC pieces into homogeneous spindle-shaped and typical fibroblast-like shape cells. By using flow cytometery MSCs showed positive for CD73, and negative for CD31. the morphology of viable MSCs in the beads did not significantly show a different morphology pattern before and after the bead formation process. These findings are indicated that when mixed enzymatic-explant procedure is performed MSCs can be isolated faster and much higher from WJ. These finding is important in comparing with time consuming explants culture for isolation of MSCs.展开更多
Background: Recent studies have focused on generating of insulin-producing cells (IPCs) from pluripotent stem cells. Producing of precursor's population with pancreatic endoderm properties is a challenging issue i...Background: Recent studies have focused on generating of insulin-producing cells (IPCs) from pluripotent stem cells. Producing of precursor's population with pancreatic endoderm properties is a challenging issue in front of regenerative medicine investigators. Previous studies have shown that during pancrease development in lower portion of foregut, signals from notochord suppress sonic hedgehog (Shh) expression and lead to increase expression of pancreatic duodenal homeobox-1 (Pdx-1) as a marker for pancreatic precursor's cells. Therefore, Shh repression is considered as a critical step in IPCs generation protocols. Objective: Isolation and characterization of human umbilical cord mesenchymal stem cells (HUC-MSCs) is the aim of current study. As well as the role of basic fibroblast growth factor (bFGF) alone and in combination with cyclopamine are investigated in creating cells with Pdx-1 expression ability. Methods: Cells differentiate into definitive endoderm by adding activin A and wnt-3α into RPMI medium supplemented with for 3 days. At the second stage, the cells are washed with phosphate-buffered saline (PBS). One group (group A) is treated with bFGF for 5 days. Second group (group B) is treated with cyclopamine-KADD for 5 days. Third group (group C) is treated with bFGF and cyclopamine-KAAD for 5 days. Forth group (group D) is untreated as control. Result: Our results show that bFGF and cyclopamine in combination induce more expression of Pdx-1 in HUC-MSCs.展开更多
基金supported by grants from the National Basic Research Development Program of China(2013CB5313002012CB910402)+4 种基金the National Natural Science Foundation of China(31071879, 31000488)Major Science and Technology Projects of Zhejiang Province, China(2011C13030)the Natural Science Foundation of Zhejiang Province, China(Z2100730)the NiH(R01-NS37717)National Multiple Sclerosis Society (RG3276)
文摘Axonal myelination is an essential process for normal functioning of the vertebrate central nervous system. Proper formation of myelin sheaths around axons depends on the timely differentiation of oligodendrocytes. This differentiation occurs on a predictable schedule both in culture and during development. However, the timing mechanisms for oligodendrocyte differentiation during normal development have not been fully uncovered. Recent studies have identified a large number of regulatory factors, including cell-intrinsic factors and extracel- lular signals, that could control the timing of oligodendrocyte differentiation. Here we provide a mechanistic and critical review of the timing control of oligodendrocyte differentiation.
文摘Western Liaoning of northeastern China is world-renowned for the MesozoicJehol biota, especially for yielding many feathered dinosaurs, primitive birds, mammals and fossilangiosperm. This paper describes a complete specimen of a symmetrodont mammal with well-preservedhairs and soft tissue from the basal part of the Yixian Formation in the Sihetun area, Beipiao,western Liaoning. It is significant for understanding the morphology, osteology, phylogeny and lifehabits of Mesozoic symmetrodont mammals.
基金This work was supported by the National Natural Science Foundation of China；the U. S. National Science Foundation （EAR）；the National Geographic Society；the Jurassic Foundation, the Hilmar Sallee bequest, George Washington University；the Chinese Academy of Sciences.
文摘A new stegosaur species, Jiangjunosaurusjunggarensis, gen. et sp. nov., is erected based on a specimen collected from the Upper Jurassic upper section of the Shishugou Formation in the Junggar Basin, Xinjiang, China. It represents the first stegosaur from the Jurassic of Xinjiang and increases the diversity of the dinosaur fauna in the Shishugou Formation. The new genus is characterized by symmetrical and proportionally wide tooth crowns, a sub-rectangular axial neural spine seen in lateral view, and large openings on the lateral surfaces of the cervical centra. A preliminary character analysis suggests that this new taxon is more derived than the Middle Jurassic stegosaur Huayangosaurus but more primitive than most other known stegosaur species.
基金supported by the National Basic Research Development Program of China (2013CB531303, 2012CB910402)the National Natural Science Foundation of China (31101642, 31372150)+1 种基金the Science and Technology Key Project of Zhejiang Province, China (2011C13030)the National Institutes of Health, USA (R01-NS37717)
文摘Dear Editor, Although various components of the Wnt/β-catenin pathway have been investigated, there are conflicting reports on the roles of Wnt/β-catenin signaling in oligodendrogenesis and differentiation. For instance, the △Exon3 mutation of β-catenin[14], which stabilizes β-catenin by deletion of the phosphorylation site for the destruction complex, significantly inhibits the differentiation of oligodendrocytes, but knockout of β-catenin also delays it.
文摘Background:Testicular torsion(TT)is an acute inflammatory process leading to male infertility.Today,anti-i nflammatory effects of exosomes derived from blood serum are used in various laboratory procedures.In the present study,the anti-i nflammatory effects of blood-serum-derived exosomes in treatment of acute inflammation following TT in mice were evaluated.Materials and Methods:Eighteen male mice were grouped as healthy control,TT,and TT+exosome.TT was induced surgically,and exosomes were extracted from blood serum and administrated by a single intratesticular injection(10 IU).Malondialdehyde(MDA)and Griess assays were used to evaluate the level of oxidative stress.Sperm indices,testosterone(Tes),and apoptotic gene expression(p-53,Bcl2,and Caspase-3)were also assessed.H&E and immunohistochemistry(IHC)stainings were used for histopathological investigations.Data analysis was applied by SPSS(v.19)software.Results:Oxidative stress and apoptotic genes expression were increased significantly(p<0.05)in TT group compared with control.Sperm parameters and Tes were significantly increased,and expression of apoptotic genes was significantly reduced in TT+exosome group(p<0.05).Conclusion:Since the blood-serum-derived exosomes have anti-i nflammatory features,the intratesticular application of blood-serum-derived exosomes can be used clinically in acute phase of orchitis following TT to inhibit testicular inflammation.
基金Supported by scientific society grant from the Research Vice Chancellor of Islamic Azad University,Tabriz Branch
文摘Objective:To study the role of Quercetin in streptozotocin-induced diabetes in rals.Methods:Wistar male rat(n=40) were allocated into three groups,control group(n=10) and Quercetin(QR) group received 15 mg/kg(IP) QR.(n=10),and diabetic group that received 55 mg/kg(IP)streptozotocin(STZ)(n=20) which was subdivided to two groups of 10;STZ group and treatment group.Treatment group received 55mg/kg(IP) STZ plus 15 nig/kg QR,daily lor 4 weeks,respectively:however,the control group just received an equal volume of distilled water dailv(IP).Diabetes was induced by a single(IP) injection of streptozotocin(55 mg/kg).Animal-were kept in standard condition.Twenty-eight days after inducing diabetic,5 mL blood were collected for TAC,MPA and Ox-LDL levels and liver tissues of rat in whole groups were removed then prepared for apoptosis analysis by Tunel method.Results:Apoptotic cells significantly decreased in group that has received 15 mg/kg(IP) Quercetin(P<0.05) in comparison to experimental groups(P<0.05).Conclusions:Since in our study 15 nig/kg(IP) Quercetin have significantly Preventive ellecl on liver cells damages by reducing number of apoptotic cells in Liver,so it seems that using it can be effective for treatment in diabetic rat.
基金The financial support was prepared by the Research Council of Kermanshah University of Medical Sciences for PhD thesis(Research project No.4000077).
文摘Background:Endometriosis can lead to infertility.Since there is no definitive treat-ment for endometriosis,animal modelling seems necessary to examine the possible treatments.Mouse endometrium cannot be separated for endometriosis induc-tion.In addition,transplantation of uterus into the abdominal viscera to induce endometriosis causes organ damage.In this study,we defined a new model of en-dometriosis leading to separability of endometrium and a safe anatomical region for transplantation.Methods:Forty female mice were allocated to 5 groups:1,sham;2,allograft uterus transplantation of mice to anterior abdominal wall of mice;3,allograft uterus trans-plantation of mice to mesentery of mice;4,xenograft endometrial transplantation of rat to anterior abdominal wall of mice;5,xenograft endometrial transplantation of rat to mesentery of mice.Adult female rats with a previous pregnancy experience were selected and placed in the vicinity of male rats for 2 weeks to induce estrogen secre-tion and increase endometrial thickness.Results:In the 4th group of animals,compared to sham,the peritoneal concentrations of VEGF-A,TNF-α,NO,MDA,and serum levels of CA-125 and IL-37 were increased and total body weight was decreased,while weight and size of endometrial lesions were increased significantly(P<.05).Genes expression of HOXA10 and HOXA11 were decreased significantly(P<.05)in groups 2 and 4 compared to sham.Conclusions:Xenograft transplantation of endometrium from rat to anterior abdomi-nal wall of mice can potentially mimic human endometriosis morphologically,histo-logically,and genetically.
文摘Objective: To evaluate the impact of Olea (O.) europaea extract on markers of oxidative stress and apoptosis of ovarian tissues in a rat model of torsion/detorsion-induced ovarian damage. Methods: A total of 28 Wistar female rats were randomly assigned into 4 groups, with 7 rats in each group. The sham group received a 2.5 cm longitudinal incision in the midline part of the abdomen which was then sutured with 5-0 nylon thread;the torsion/detorsion group underwent torsion induction for 3 h followed by reperfusion for 10 days;the torsion/detorsion+O. europaea group received 300 mg/kg hydro-alcoholic extract of O. europaea 30 min before detorsion, followed by reperfusion for 10 days;and the O. europaea group only received 300 mg/kg hydro-alcoholic extract of O. europaea for 10 days. After the treatment period, blood samples were taken;the levels of estrogen, glutathione peroxidase, superoxide dismutase, and malondialdehyde were assayed. The histological changes, as well as the rate of apoptosis in ovarian tissues, were also carried out by histomorphometric analysis at day 10 post-procedure. Results: Histological comparisons demonstrated a significant detrimental change in the torsion/detorsion group as compared with other groups. The number of pre-antral and antral follicles and corpus luteum was significantly decreased in the torsion/detorsion group compared with the sham group, while treatment with O. europaea could enhance their numbers (P<0.05). The index of apoptosis and the number of atretic body in the ovarian tissue were significantly higher in the torsion/detorsion group compared with the sham group (P<0.05). The concentrations of glutathione peroxidase, estrogen, and superoxide dismutase as well as the mRNA expression of Bcl-2 were considerably diminished in the torsion/detorsion group while they were elevated in the torsion/detorsion+O. europaea group (P<0.05) compared with the torsion/detorsion group. The serum malondialdehyde level and the mRNA expression of Bax were markedly increased during ischemia, while treatment with O. europaea significantly diminished the increased concentrations of malondialdehyde and Bax level in the torsion/detorsion+O. europaea group (P<0.05). Conclusions: O. europaea extract can reduce the degree of tissue damage induced by oxidative stress and apoptosis in the ovary following ovarian ischemia/reperfusion.
基金supported by the National Natural Sciences Foundation of China (31471955)the Natural Science Foundation of Zhejiang Province, China (LY17C090006+1 种基金 Q16C090017 LY18H090014)
文摘Oligodendrocytes（OLs） are myelinating glial cells that form myelin sheaths around axons to ensure rapid and focal conduction of action potentials. Here, we found that an axonal outgrowth regulatory molecule, AATYK（apoptosis-associated tyrosine kinase）, was up-regulated with OL differentiation and remyelination. We therefore studied its role in OL differentiation. The results showed that AATYK knockdown inhibited OL differentiation and the expression of myelin genes in vitro. Moreover, AATYKdeficiency maintained the proliferation status of OLs but did not affect their survival. Thus, AATYK is essential for the differentiation of OLs.
基金supported by the National Natural Sciences Foundation of China (31471955 and 31372150)the National Basic Research Development Program (973 Program) of China (2013CB531300)
文摘Oligodendrocytes（OLs） are glial cells that form myelin sheaths around axons in the central nervous system（CNS）.Loss of the myelin sheath in demyelinating and neurodegenerative diseases can lead to severe impairment of movement.Understanding the extracellular signals and intracellular factors that regulate OL differentiation and myelination during development can help to develop novel strategies for enhancing myelin repair in neurological disorders.Here,we report that TAPP1 was selectively expressed in differentiating OL precursor cells（OPCs）.TAPP1 knockdown promoted OL differentiation and myelin gene expression in culture.Conversely,over-expression of TAPP1 in immature OPCs suppressed their differentiation.Moreover,TAPP1 inhibition in OPCs altered the expression of Erk1/2 but not AKT.Taken together,our results identify TAPP1 as an important negative regulator of OPC differentiation through the Mek/Erk signaling pathway.
文摘BACKGROUND： Lead has caused widespread pollution in the environment due to the numerous industrial applications. One principle target for lead in the human body is the central nervous system However, research has demonstrated that neurotoxic effects of lead can be ameliorated by antioxidant agents, such as vitamin C. OBJECTIVE： To investigate the protective effects of vitamin C supplementation against lead-induced apoptosis in the adult rat hippocampus, as well as changes in pro-apoptotic protein Bax expression. DESIGN, TIME AND SETTING： A randomized, controlled, animal study was performed at the College of Medicine, Iran University of Medical Sciences from December 2007 to April 2009. MATERIALS： Lead acetate and vitamin C were purchased from Sigma, USA. METHODS： Thirty male rats were randomly assigned to three groups, with 10 rats in each group： control, lead, and lead ＋ vitamin C. Rats from the lead group received intraperitoneal administration of lead 20 mg/kg per day for 7 days. Rats from the lead ＋ vitamin C group received ascorbic acid 500 mg/kg per day in addition to lead acetate （as per the lead group）. MAIN OUTCOME MEASURES： After 7 days of vitamin C administration, hippocampal cell apoptosis was observed using uranyl acetate and lead citrate stainings, hippocampal Bax protein expression was detected by Western blot analysis, and blood lead levels were measured by atomic absorption spectrometry. RESULTS： Vitamin C supplementation significantly reduced lead-induced hippocampal cell apoptosis and decreased hippocampal Bax protein expression. However, vitamin C treatment did not significantly decrease blood lead levels. CONCLUSION： Vitamin C significantly decreased Bax expression and reduced lead-induced hippocampal cell apoptosis.
文摘The ex-copula penile dorsiflexion reflex(PDFR)is an established measure of sexual dysfunction in male rat models of spinal cord injury.Although the PDFR after complete spinal transection is well described,information regarding the more clinically relevant incomplete spinal contusion injury model is limited.This study examined,using two-dimensional(2D)kinematic analysis,the relationship between the PDFR and degree of white matter sparing(WMS).Male Wistar rats received a T9 contusion with varying degrees of impactor forces.Weekly kinematic recordings of the PDFR were made 3-8 weeks postinjury.Sexual reflex components examined included maximum angle of penile dorsiflexion,total penile event duration,and penile ascent speed.Post hoc comparison between animals grouped based upon injury severity(moderate-severe:13.33%-17.15%WMS vs moderate:20.85%-33.50%WMS)ndicated PDFR effects.Specifically,the numbers of animals with more moderate contusions having data points above the median n both maximum angle of penile dorsiflexion and penile ascent speed were significantly lower than animals with more severe njuries.Total penile event duration was also affected but only at more chronic time points(6-8 weeks).Thus,2D kinematic analysis of the PDFR allows for more consistent and quantifiable analysis of the subtle differences that can occur between injury severity groups in the rat contusion model.
文摘Objective: To evaluate effect of Phaseolus vulgaris (P. vulgaris) on the breastfeeding in female rats. Methods: This experimental study was done from May 2018 to December 2018 in the Anatomical Department of Medical School in Kermanshah University of Medical Sciences in Iran. In this study, after one-week adaptation and fertilization by male, 40 female rats within 20 days of pregnancy (on average, every mother had 10 newborns) were equally separated into four groups (animals were administrated after delivery of offspring). Group 1 was control group receiving normal saline interaperitoneally, and groups 2, 3, 4 were treatment groups receiving the dose of 20, 50, 100 mg/kg of P. vulgaris interaperitoneally respectively once a day for 60 days. The prolactin hormone was measured by radio immune assay, number and diameter of alveoli via histological and morphometrical examinations, and receptor prolactin gene expression by real-time polymerase chain reaction method. Results: P. vulgaris significantly improved alveoli's number and diameter, prolactin hormone and receptor prolactin expression when compared to the control group (P<0.001). Conclusions: P. vulgaris is helpful to improve the breastfeeding parameters of rats' mammary glands.
文摘Liver injury in the setting of human immunodeficiency virus(HIV) infection is more commonly attributed to viral hepatitis or highly active antiretroviral treatment(HAART) toxicity. The severity of liver injury is an important cause of morbidity and mortality. The emergence of autoimmune diseases, particularly autoimmune hepatitis(AIH) in the setting of HIV infection, is rare. Previous reports indicate that elevated liver enzymes are a common denominator amongst these patients. We present two patients with HIV infection, on HAART, with virological suppression. Both patients presented with elevated liver enzymes, and following liver biopsies, were diagnosed with AIH. The clinical course of these patients underscore the therapeutic value of corticosteroids, and in some cases, addition of immunosuppression for AIH treatment.
文摘Nitric oxide(NO),a member of the reactive nitrogen species family,plays a role in several physiologic processes,including vasculogenesis and angiogenesis,growth and puberty,and senescence and apoptosis.NO plays an important role in the production of ovarian steroids,ovulation,and follicular apoptosis.In other words,increased activity of nitric oxide synthase(NOS)leads to an increased amount of NO,which triggers production of prostaglandins and inflammatory cascades which facilitate follicular rupture and atresia.NO concentration elevation inhibits steroid synthesis in luteal and granulosa cells.Since NO is a major paracrine mediator of various biological processes,as well as a key factor in both the reproductive cycle and embryo implantation,oversynthesis of NO in the uterus results in toxicity and inflammation in epithelial cells and immunorejection of implantation.In the male physiological system,NO synthesized by NOS plays a major role in erectile function and androgen secretion,as well as semen parameters,and oocyte junction to the sperm.Furthermore,this supposedly simple molecule is involved in a number of other functions,such as germ cell evolution,connections between sertoli cells and germ cells in the blood-testis barrier,homodynamic contraction,and germ cell apoptosis.Moreover,NO is considered a key factor in male fertility due to its widespread distribution in both normal and diseased testis tissue.The difference of expression level of NOS in normal and pathological states is a probable cause of fertility destructive processes.
文摘Because of increased need to tissue and organ transplantation, tissue engineering (TE) researches have significantly increased in recent years in Iran. The present study explored briefly the advances in the TE approaches in Iran. Through comprehensive search, we explored main TE components researches include cell, scaffold, growth factor and bioreactor conducted in Iran. The field of TE and regenerative medicine in Iran dates back to the early part of the 1990 decade and the advent of stem cell researches. During past two decades, Iran was one of leader in stem cell research in Middle East. The next major step in TE was application and fabrication of scaffolds for TE in the early 2000s with focused on engineering bone and nerve tissue. Iranian researchers extensively used natural scaffolds in their studies and hybridized natural polymers and inorganic scaffolds. There are many universities and government research institutes are conducting active research on tissue-engineering technologies. Limitations to TE in Iran include property design and validation of bioreactors. In conclusion, in the last few years, fields of tissue engineering and regenerative medicine such as stem cell technology and scaffolds have progressed in Iran, but one of the biggest challenges for TE is bioreactors researches.
文摘Exponentially growing cultures of human bladder tumor cells (RT4 and T24) were treated with Vitamin C (VC) alone, Vitamin K3 (VK3) alone, or with a VC:VK3 combination continuously for 5 days or treated with vitamins for 1 h, washed with PBS and then incubated in culture medium for 5 days. Co-administration of the vitamins enhanced the antitumor activity 12- to 24-fold for the RT-4 cells and 6- to 41-fold for the T24 cells. Flow cytometry of RT4 cells exposed to the vitamins revealed a growth arrested population and a population undergoing cell death. Growth arrested cells were blocked near the G0/G1-S-phase interface, while cell death was due to autoschizis. Catalase treatment abrogated both cell cycle arrest and cell death which implicated hydrogen peroxide (H2O2) in these processes. The H2O2 production resulted in a moderate increase in lipid peroxidation and depletion of cell thiol levels. Analysis of cellular ATP levels revealed a transient increase in ATP production for VC and the VC:VK3 combination, but decreased ATP levels following VK3 treatment. Lipid peroxidation, thiol depletion and ATP modulation occurred at a 17-fold lower concentration in the vitamin combination than with either vitamin alone. These results suggested that the increased cytotoxicity of the vitamin combination was due to redox cycling and increased oxidative stress.
文摘Pectus excavatum (PE) and pectus carinatum (PC) are relatively common deformities involving the anterior chest wall, occurring in 1:1000 and 1:1500 live births, respectively. While the etiology remains an enigma, the association of pectus deformities with other skeletal abnormalities suggests that connective tissue disease may play a role in their pathogenesis. Clinical features of these deformities vary with severity, as determined by the Haller index and Backer ratio, but frequently include cardiac and respiratory abnormalities. Importantly, there exist profound psychosocial implications for children afflicted with these defofrmities, including but not limited to feelings of embarrassment and maladaptive social behaviors. These debilitating characteristics have prompted the development of novel medical and surgical corrective techniques. The correction of pectus deformities reduces the incidence of physiological complications secondary to chest wall malformation, while simultaneously improving body image and psychosocial development in the affected pediatric population. The Ravitch (open) and Nuss (minimally invasive) procedures remain the most frequently employed methods of pectus deformity repair, with no difference in overall complication rates, though individual complication rates vary with treatment. The Nuss procedure is associated with a higher rate of recurrence due to bar migration, hemothorax, and pneumothorax. Postoperative pain management is markedly more difficult in patients who have undergone Nuss repair. Patients undergoing the Ravitch procedure require less postoperative analgesia, but have longer operation times and a larger surgical scar. The cosmetic results of the Nuss procedure and its minimally invasive nature make it preferable to the Ravitch repair. Newer treatment modalities, including the vacuum bell, magnetic mini-mover procedure (3MP), and dynamic compression bracing (DCB) appear promising, and may ultimately provide effective methods of noninvasive repair. However, these modalities suffer from a lack of extensive published evidence, and the limited number of studies currently published fail to adequately define their long-term effectiveness.
文摘We report combination of explants and enzymatic protocol as mixed enzymatic-explant procedure to faster extraction of MSCs from WJ. Umbilical cords (UC) were collected from Imam Khomini Hospital. For explant outgrowth, 6 - 9 pieces of WJ were transferred onto tissue culture flask and waited for attachment. For mixed enzymatic-explant, 1 cm3 pieces WJ were placed in enzymatic cocktail comprising 4 mg/ml Collagenase Type I and 1 mg/ml Hyaluronidase and 0.1% trypsin-EDTA. Then isolated cells were analyzed for surface cell markers such as CD73, CD31. Isolated 1.0 × 106 MSCs/ml were encapsulated in alginate hydrogel. Cells with MSCs phenotype were isolated from mixed enzymatic-explant and explant procedures within 24 - 48 hrs and 7 - 10 days, respectively. Both of procedures were shown to form clumps and colonies with dense centers. Phenotypic changes gradually appeared as round cell in UC pieces into homogeneous spindle-shaped and typical fibroblast-like shape cells. By using flow cytometery MSCs showed positive for CD73, and negative for CD31. the morphology of viable MSCs in the beads did not significantly show a different morphology pattern before and after the bead formation process. These findings are indicated that when mixed enzymatic-explant procedure is performed MSCs can be isolated faster and much higher from WJ. These finding is important in comparing with time consuming explants culture for isolation of MSCs.
文摘Background: Recent studies have focused on generating of insulin-producing cells (IPCs) from pluripotent stem cells. Producing of precursor's population with pancreatic endoderm properties is a challenging issue in front of regenerative medicine investigators. Previous studies have shown that during pancrease development in lower portion of foregut, signals from notochord suppress sonic hedgehog (Shh) expression and lead to increase expression of pancreatic duodenal homeobox-1 (Pdx-1) as a marker for pancreatic precursor's cells. Therefore, Shh repression is considered as a critical step in IPCs generation protocols. Objective: Isolation and characterization of human umbilical cord mesenchymal stem cells (HUC-MSCs) is the aim of current study. As well as the role of basic fibroblast growth factor (bFGF) alone and in combination with cyclopamine are investigated in creating cells with Pdx-1 expression ability. Methods: Cells differentiate into definitive endoderm by adding activin A and wnt-3α into RPMI medium supplemented with for 3 days. At the second stage, the cells are washed with phosphate-buffered saline (PBS). One group (group A) is treated with bFGF for 5 days. Second group (group B) is treated with cyclopamine-KADD for 5 days. Third group (group C) is treated with bFGF and cyclopamine-KAAD for 5 days. Forth group (group D) is untreated as control. Result: Our results show that bFGF and cyclopamine in combination induce more expression of Pdx-1 in HUC-MSCs.
