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41.
Nooreddin Nematollahi Mojtaba Rezazadeh Valojerdi 《Journal of assisted reproduction and genetics》1999,16(7):380-384
Purpose:
Our purpose was to evaluate the beneficial effects of long-term coculture of Vero cells on the development of frozen–thawed two-cell mouse embryos.
Methods:
Two-cell mouse embryos were frozen slowly with 1,2-propandiol and sucrose as cryoprotectants and thawed rapidly, followed by stepwise dilution. Vero cells were cultured in drops of RPMI 1640 to establish monolayers. Frozen–thawed embryos were cultured alone (control) or cocultured with Vero cells. The rate of development in both groups was compared.
Results:
After 4 days of culture, significantly more embryos in coculture were developed to expanded blastocysts (61 vs 37% for controls; P 0.0001). In addition, on the fifth day of cultivation, more embryos in coculture showed the potential of hatching from the zona pellucida (26 vs 7% in controls; P 0.0001). The rate of degeneration in coculture was also much lower than in controls (6 and 15%, respectively).
Conclusions:
Coculture of cryopreserved preimplantation-stage embryos with Vero cells seems to be a useful tool to eliminate the postthaw deleterious effect of freezing and also to obtain better-quality embryos appropriate for transfer. 相似文献
42.
Targeting TGFbeta signaling for cancer therapy 总被引:3,自引:0,他引:3
Transforming growth factor (TGF) betas are multifunctional polypeptides that regulate several cellular functions, including cell growth and differentiation, extra cellular matrix production, motility and immunosuppression. The growth-inhibiting properties of TGFbeta have gained much attention into its role as a tumor suppressor. There is, however, now increasing evidence that TGFbeta switches roles, from tumor suppressor to tumor promoter, as the tumor progresses. Given the integral role of TGFbeta in the tumor progression, it follows that TGFbeta signaling offers an attractive target for cancer therapy. Several strategies including the use of antisense oligonucleotides for TGFbeta, TGFbeta antibodies, dominant negative TGFbeta receptor II, and small drug-molecules to inhibit TGFbeta receptor I kinase have shown great promise in the preclinical studies. These new findings, coupled with progressing clinical trials indicate that inhibition of TGFbeta signaling may, indeed, be a viable option to cancer therapy. This review summarizes the TGFbeta signaling, the dual role of TGFbeta--as a tumor suppressor and tumor promoter, and various strategies targeted against TGFbeta signaling for cancer therapy. The next few years promise to better our understanding of approaching cancer therapy with an eye to the inhibition of TGFbeta signaling. 相似文献
43.
Arvand M Mousavi MF Zanjanchi MA Shamsipur M 《Journal of pharmaceutical and biomedical analysis》2003,33(5):975-982
A coated wire triamterene-selective electrode based on the incorporation of a triamterene–tetraphenylborate ion-pair in a poly(vinylchloride) coating membrane was constructed. The influence of membrane composition, temperature, pH of the test solution, and foreign ions on the electrode performance were investigated. The electrode showed a Nernstian response over a triamterene concentration range from 1.0×10−6 to 3.5×10−2 M, at 25 °C, and was found to be very selective, precise, and usable within the pH range 4.5–7.5. The standard electrode potentials, E°, were determined at 15, 20, 25, 30, 35, 40 and 45 °C and used to calculate the isothermal temperature coefficient (dE°/dt) of the electrode. Temperatures higher than 45 °C seriously affected the electrode performance. The electrode was successfully applied to the potentiometric determination of triamterene hydrochloride both in pure solutions and in pharmaceutical preparations. 相似文献
44.
The objective of the present study was to investigate the relationship between oral hygiene behaviours and general hygiene behaviours among Iranian adolescents living in Mashhad. A representative stratified random sample of 1,054 Iranian adolescents, in the sixth grade of school, answered a 37-item questionnaire on socio-demographic characteristics, frequency of toothbrushing behaviours, frequency of taking showers, and frequency of changing underwear, as measures of general hygiene behaviours. Binary logistic-regression analysis was employed to test the association between toothbrushing behaviours and general hygiene behaviours. The results showed that toothbrushing frequency was significantly associated with the frequency of taking showers (odds ratio: 2.40; 95% confidence interval: 1.86, 3.09) and the frequency of changing underwear (odds ratio: 2.14; 95% confidence interval: 1.65, 2.78). These associations were significant for girls and boys when tested separately and remained significant after adjusting for gender and father's education level. Girls were significantly more likely than boys to practice oral hygiene and general hygiene behaviours. In conclusion, there was a positive association between general hygiene and oral hygiene behaviours among Iranian adolescents. This association has important applications for planning health and hygiene-promoting programmes. 相似文献
45.
Mahdieh Babaiasl Seyyed Hamed Mahdioun Poorya Jaryani Mojtaba Yazdani 《Disability and rehabilitation. Assistive technology》2016,11(4):263-280
Cerebrovascular accident (CVA) or stroke is one of the leading causes of disability and loss of motor function. Millions of people around the world are effected by it each year. Stroke results in disabled arm function. Restoration of arm function is essential to regaining activities of daily living (ADL). Along with traditional rehabilitation methods, robot-aided therapy has emerged in recent years. Robot-aided rehabilitation is more intensive, of longer duration and more repetitive. Using robots, repetitive dull exercises can turn into a more challenging and motivating tasks such as games. Besides, robots can provide a quantitative measure of the rehabilitation progress. This article overviews the terms used in robot-aided upper-limb rehabilitation. It continues by investigating the requirements for rehabilitation robots. Then the most outstanding works in robot-aided upper-limb rehabilitation and their control schemes have been investigated. The clinical outcomes of the built robots are also given that demonstrates the usability of these robots in real-life applications and their acceptance. This article summarizes a review done along with a research on the design, simulation and control of a robot for use in upper-limb rehabilitation after stroke.
- Implications for Rehabilitation
Reviewing common terms in rehabilitation of upper limb using robots
Reviewing rehabilitation robots built up to date
Reviewing clinical outcomes of the mentioned rehabilitation robots
46.
47.
Farhad Etezadi Pejman Pourfakhr Mojtaba Mojtahedzade Atabak Najafi Reza Shariat Moharari Kourosh Karimi Yarandi Mohammad Reza Khajavi 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2012,20(1):36
Background
Recently, several studies have been conducted to determine the optimal strategy for intra-operative fluid replacement therapy in renal transplantation surgery. Since infusion of sodium bicarbonate as a buffer seems to be safer than other buffer compounds (lactate, gluconate, acetate)that indirectly convert into it within the liver, We hypothesized tight control of metabolic acidosis by infusion of sodium bicarbonate may improve early post-operative renal function in renal transplant recipients.Methods
120 patients were randomly divided into two equal groups. In group A, bicarbonate was infused intra-operatively according to Base Excess (BE) measurements to achieve the normal values of BE (−5 to +5 mEq/L). In group B, infusion of bicarbonate was allowed only in case of severe metabolic acidosis (BE ≤ −15 mEq/L or bicarbonate ≤ 10 mEq/L or PH ≤ 7.15). Minute ventilation was adjusted to keep PaCO2 within the normal range. Primary end-point was sampling of serum creatinine level in first, second, third and seventh post-operative days for statistical comparison between groups. Secondary objectives were comparison of cumulative urine volumes in the first 24 h of post-operative period and serum BUN levels which were obtained in first, second, third and seventh post-operative days.Results
In group A, all of consecutive serum creatinine levels were significantly lower in comparison with group B. With regard to secondary outcomes, no significant difference between groups was observed.Conclusion
Intra-operative tight control of metabolic acidosis by infusion of Sodium Bicarbonate in renal transplant recipients may improve early post-operative renal function. 相似文献48.
Pardakhty A Shakibaie M Daneshvar H Khamesipour A Mohammadi-Khorsand T Forootanfar H 《Journal of microencapsulation》2012,29(3):219-224
In this study, different positively charged niosomal formulations containing sorbitan esters, cholesterol and cetyl trimethyl ammonium bromide were prepared by film hydration method for the entrapment of autoclaved Leishmania major (ALM). Size distribution pattern and stability of niosomes were investigated by laser light scattering method and ALM encapsulation per cent was measured by the bicinchoninic acid method. Finally, the selected formulation was used for the induction of the immune response against cutaneous leishmaniasis in BALB/c mice. Size distribution curves of all the formulations followed a log-normal pattern and the mean volume diameter was in the range 7.57-15.80 μm. The mean volume diameters were significantly increased by adding Tween to Span formulations (p?0.05). The percentage of ALM entrapped in all formulations varied between 14.88% and 36.65%. In contrast to ALM, in vivo studies showed that the niosomes containing ALM have a moderate effect in the prevention of cutaneous leishmaniasis in BALB/c mice. 相似文献
49.
Hounsome JD Baillie S Noofeli M Riboldi-Tunnicliffe A Burchmore RJ Isaacs NW Davies RL 《Infection and immunity》2011,79(11):4332-4341
Mannheimia haemolytica is the etiological agent of pneumonic pasteurellosis of cattle and sheep; two different OmpA subclasses, OmpA1 and OmpA2, are associated with bovine and ovine isolates, respectively. These proteins differ at the distal ends of four external loops, are involved in adherence, and are likely to play important roles in host adaptation. M. haemolytica is surrounded by a polysaccharide capsule, and the degree of OmpA surface exposure is unknown. To investigate surface exposure and immune specificity of OmpA among bovine and ovine M. haemolytica isolates, recombinant proteins representing the transmembrane domain of OmpA from a bovine serotype A1 isolate (rOmpA1) and an ovine serotype A2 isolate (rOmpA2) were overexpressed, purified, and used to generate anti-rOmpA1 and anti-rOmpA2 antibodies, respectively. Immunogold electron microscopy and immunofluorescence techniques demonstrated that OmpA1 and OmpA2 are surface exposed, and are not masked by the polysaccharide capsule, in a selection of M. haemolytica isolates of various serotypes and grown under different growth conditions. To explore epitope specificity, anti-rOmpA1 and anti-rOmpA2 antibodies were cross-absorbed with the heterologous isolate to remove cross-reacting antibodies. These cross-absorbed antibodies were highly specific and recognized only the OmpA protein of the homologous isolate in Western blot assays. A wider examination of the binding specificities of these antibodies for M. haemolytica isolates representing different OmpA subclasses revealed that cross-absorbed anti-rOmpA1 antibodies recognized OmpA1-type proteins but not OmpA2-type proteins; conversely, cross-absorbed anti-rOmpA2 antibodies recognized OmpA2-type proteins but not OmpA1-type proteins. Our results demonstrate that OmpA1 and OmpA2 are surface exposed and could potentially bind to different receptors in cattle and sheep. 相似文献
50.