Evolution of compressive mechanical properties of early hypertrophic scar during laser treatment.

Laser therapy has been widely used in the treatment of hypertrophic scars (HPS), but whether the mechanical properties of HPS tissue after laser treatment can be restored to those of normal skin remains unclear. In this paper, the relationship between the evolution of compressive mechanical properties and histological changes of HPS tissues following three successive combined pulsed dye laser (PDL) and fractional CO2 laser (CO2) treatments was investigated by compression tests and histological analysis. The early HPS model of rabbit ear was established by CO2 laser ablation. The loading-unloading tests and strain creep tests under the compression forces of 1 N, 2 N, and 3 N were carried out for normal skin, untreated HPS and HPS after different treatment times, respectively. The results showed that the compression ratio λ of all tissues revealed force dependence and rose with the increasing compression force, which was similar to the trend of most biological soft tissues. The histological changes of HPSs following laser treatment have a significant influence on the compressive mechanical response. Compared with the normal skin, the toughness and anti-deformation ability of HPS reduced due to the proliferation of collagen fibers and the destruction of elastic fibers, resulting in higher energy dissipation, compression ratio λ, and stable creep rate D, and lower elastic modulus. After three successive combined PDL/ CO2 laser treatments, the compressive mechanical properties and creep properties of HPS gradually approached that of the normal skin owing to the gradual restoration of the amount and distribution of collagen and elastic fibers in HPS. The results provide a new method for evaluating the clinical efficacy of laser therapy for treatment of HPS tissue.

[Clinical effect of adding hMG to the follicular phase long protocol for standard group with normal ovarian reserve function].

Objective: To investigate the impact of adding human menopausal gonadotropin (hMG) for in vitro fertilization-embryo transfer pregnancy outcomes in a standard population of non-advanced age with normal ovarian reserve function using a long follicular phase protocol. Methods: Clinical data of 489 patients with normal ovarian reserve function, who were admitted from January 2018 to January 2020 in the Affiliated Hospital of Guizhou Medical University and underwent in vitro fertilization for the first time with the long follicular phase protocol in fresh cycles, were retrospectively analyzed. The patients were divided into three groups according to whether or not to add urine-derived hMG and the timing of addition: non-addition group (group A), medium-term hMG group (group B1), whole course hMG group (group B2); the laboratory parameters of each group were observed, and the effect of ovulation induction drugs and pregnancy outcomes were compared. Results: The ages of B1 and B2 groups were significantly higher than that of group A (P=0.019 and P=0.011). The basal FSH level of group B2 was significantly higher than those of group A and group B1 (P<0.01 and P=0.006), and the basal FSH/LH ratio of group B2 was significantly higher than that of group B1 (P=0.009). Antral follicle counts of group A and group B1 were significantly higher than that of group B2 (P=0.007 and P=0.017). The superior embryo rate of group B2 [(47±27)%] was significantly higher than that of group A (P=0.017). The embryo implantation rate of group B1 was significantly lower than those of group A and group B2 (P=0.043 and P<0.01). The clinical pregnancy rate of group B2 [76.7% (155/202)] was significantly higher than those of group A (P=0.039) and group B1 (P<0.01). The live-birth rate of group B2 [67.3% (136/202)] was significantly higher than those of group A (P=0.017) and group B1 (P=0.001). Conclusions: For non-advanced aged patients with normal ovarian reserve function, the long protocol of follicular phase is suitable for those with relatively low ovarian reserve function. Adding hMG in the whole course of ovulation induction after gonadotropin-releasing hormone agonist reduction could improve the pregnancy outcomes by improving the quality of embryos.

[The value of intraoperative cerebral oxygen saturation in predicting postoperative neurocognitive dysfunction in elderly patients with mild cognitive impairment].

Objective: To evaluate the value of intraoperative cerebral oxygen saturation in predicting postoperative neurocognitive dysfunction (PND) in elderly patients with mild cognitive impairment. Methods: A total of 210 cases of lumbar decompression, bone grafting and fusion surgery under general anesthesia were collected in the Third Central Hospital of Tianjin from June, 2019 to January, 2020, either sex, aged 65-75 year, BMI 19.5-32.5 kg/m(2), ASA physical status Ⅱ or Ⅲ, preoperative comorbidities with mild cognitive impairment. MoCA and MMSE were used to evaluate the cognitive function of patients 1 day before the operation, 7 days and 3 monthes after operation. PND group (n=38) and non-PND group (n=172) were selected according to postoperative MMSE and MoCA scale scores and the diagnostic criteria of PND. Heart rate (HR) , mean arterial pressure (MAP), pulse oxygen saturation (SpO(2)), bispectral index (BIS), cerebral tissue oxygen saturation (SctO(2), average left and right brain SctO(2) were recorded) were recorded pre-anesthetic (T(0)), ten minutes of anesthesia(T(1)), twenty minutes of anesthesia (T(2)), thirty minutes into the operation (T(3)), one hour into the operation (T(4)), end of the surgery (T(5)), and leave the PACU (T(6)). SctO(2) at time point T(0) was the base value of SctO(2), and the maximum percentage drop in SctO(2) from the base value was calculated (SctO(2max)%). Results: The incidence of PND was 18% (38/210) in 210 elderly patients undergoing surgery. The age of PND group and non-PND group was (71.0±2.1) and (67.8±2.0) years old, and the PACU time was (57±5) and (46±8) min, respectively. Compared with the non-PND group, the age of the PND group was higher (t=2.600, P<0.05) and the PACU time was longer (t=3.039, P<0.05). At the time points T(3), T(4), T(5) and T(6), SctO(2) in the PND group was (62±10) %, (60±11) %, (64±12) % and (66±10)%, respectively, lower than that in the non-PND group (67±60) %, (68±6) %, (69±5) % and (70±7)%, respectively, and the difference was statistically significant (t=3.369, 4.906, 3.787, 2.516, all P<0.05).The MoCA and MMSE scores of the PND group were (22.9±1.2) and (24.1±1.2) points, respectively, 1 day before surgery; and the MoCA and MMSE scores of the PND group were reduced to (20.8±1.2) and (21.3±0.7) points, respectively, 7 days after surgery, with statistically significant differences (t=3.523, 5.675, all P<0.05). MoCA and MMSE scores 7 days after surgery in the non-PND group were (22.4±1.3) and (23.1±1.6) points, respectively. Compared with the non-PND group, MoCA and MMSE scores 7 days after surgery in the PND group were reduced (t=2.630, 3.108, all P<0.05). The critical value of intraoperative SctO(2max)% was 13.74%, the area under the curve of PND was predicted to be 0.907 (95%CI: 0.819-0.995), sensitivity and specificity were 88.9% and 88.5%, respectively. Conclusion: SctO(2max)%>13.74% can be used as an indicator to predict PND occurrence in elderly patients with mild cognitive impairment during lumbar surgery.

[Role and implementation experience of splints in pediatric burn rehabilitation].

The maintenance of posture and anti-contracture treatment are the critical elements of comprehensive burn rehabilitation in the overall treatment period of pediatric burns. Although domestic experts in burn discipline have formulated guidelines for burn rehabilitation, the maintenance of posture and design and manufacture of splints for anti-scar contractures in children with burns are different from that for adults with burns in many ways. Starting with paying the attention to the rehabilitation problems in pediatric burns, especially considering the anatomical, psychological, and social behavior characteristics of children in developmental period, the author's team effectively applies splints to maximize the prevention of contractures in children and maintain and improve the range of their joint movements. The splints designed to prevent contractures in pediatric burns shall fit the small limb and meet their expected goals of rehabilitation. In each aspect of the production and use of splints, it is necessary to fully evaluate and consider the scar characteristics, growth and development status, activity level, and compliance of children, and adaptability and fixation methods of the splints, so as to select the appropriate splint type and formulate the wearing plan.

Research Progress on the Relationship between Genetic Polymorphism and Violent Behavior of Patients with Schizophrenia.

ABSTRACT: Schizophrenia is a common disease characterized by thinking obstructions and accompanied by cognitive, emotional and behavioral disorders. Under the control of psychiatric symptoms, patients with schizophrenia may self-injure or impulsively wound others, resulting in public risk and increase in the burden of family and society. In recent years, many studies have shown that the violent behavior of patients with schizophrenia is related to genetic factors. This article reviews the research progress on the relationship between genetic polymorphism and violent behavior of patients with schizophrenia, analyzes the possible mechanism of the correlation between the two, puts forward the limitations of current research and the directions of future research, and provides scientific basis for risk assessment and prevention of violent behavior of patients with schizophrenia.

Upregulation of miR-504-3p is associated with favorable prognosis of acute myeloid leukemia and may serve as a tumor suppressor by targeting MTHFD2.

OBJECTIVE: Deregulated expression of miRNAs contributes to the development of acute myeloid leukemia (AML). miR-504-3p, one of these miRNAs, has been found have upregulated expression in various human malignancies. Our present study aimed to detect the expression of miR-504-3p and its biological effect in AML. PATIENTS AND METHODS: Real-time quantitative PCR was applied to evaluate the expression level of miR-504-3p in AML cell lines and the serum from AML cases. The correlations between miR-504-3p and AML patients' clinicopathological characteristics, as well as AML patients' overall survival, were statistically assessed. Moreover, we investigated the effect of miR-504-3p knockdown on AML cells by CCK-8, Transwell assays and flow cytometry, in vitro. The Western blot, RT-PCR and luciferase reporter assay were performed to evaluate the relationship between miR-504-3p and its downstream target genes. Finally, the biological function of MTHFD2 was also analyzed. RESULTS: The expression levels of miR-504-3p were significantly down-regulated in the serum of AML patients and cell lines, and its low expression was positively associated with advanced clinical stages and poor prognosis of AML patients. Functional assays indicated that overexpression of miR-504-3p leads to AML cell growth arrest, invasion and migration inhibition, and elevated rates of apoptosis. We also found that miR-504-3p regulated the expression of MTHFD2 by binding to its 3'-UTR, and knockdown of MTHFD2 significantly suppressed AML cells proliferation, migration and invasion, and promoted apoptosis. CONCLUSIONS: Our findings provide important evidence that supports the role of miR-504-3p as a tumor suppressor in AML via the inhibition of MTHFD2 expression.

Prevalence of Ureaplasma urealyticum, Chlamydia trachomatis, Neisseria gonorrhoeae and herpes simplex virus in Beijing, China.

The prevalence of sexually transmitted infection (STI) pathogens in Beijing, China, is rarely reported. In this study, 34 911 symptomatic outpatients with suspected genital infections who attended outpatient clinics in a tertiary care hospital were included to investigate the updated prevalence of Ureaplasma urealyticum (UU), Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and herpes simplex virus (HSV) from 1 January 2013 to 31 December 2016 in Beijing, China. Results indicated that a decrease trend (UU, CT, NG and HSV) in male and an increase trend (UU, CT and NG) in female were observed during the period. Patients aged 20-39 years old were mostly affected by these pathogens, while the prevalence in patients aged 20-29 years old was the highest, The prevalence of UU in male was significantly lower than in female (31.5% vs. 49.3%, P < 0.05), while the prevalence of NG in male was significantly higher than in female (2.5% vs. 0.8%, P < 0.05). In patients with co-infections, 60.6% of male and 71.4% of female were co-infected by UU + CT. In total, 11.9% and 88.1% of patients with HSV infections were confirmed to be infected by HSV-1 and HSV-2. This study could contribute to a better understanding of the current epidemiological features of UU, NG, CT and HSV among symptomatic patients attending an outpatient clinic in Beijing, China, and thus facilitate to develop more effective intervention, prevention and treatment of STI.

[Uvuplopalatal flap in OSAHS patients with anteriorand posterior pharyngeal plane stenosis].

Objective: Observation of the effect of uvuplopalatal flap for OSAHS patients with anterior and posterior pharyngeal stenosis. Method: Fifty-six patients with OSAHS who were mainly anterior posterior stenosis in the velopharyngeal plane were selected. Patients with suspending uvuplopalatal flap were used as observation group (30 cases). Patients with UPPP were used as control group (26 cases). The investigation and comparison of AHI, SaO2, scars, throat foreign body sensation, pharynx desiccation, pharynx' s tightness, pharynx discomfort and surgical satisfaction were investigated at 6-8 months after the operation. Restul: At 6-8 months after operation, the AHI and SaO2 of the two groups were significantly improved compared with those before operation(P<0.01). However, there were significant differences(P<0.01) among the indexes of scar formation, throat foreign body, sensation pharynx desiccation, pharynx' s tightness, pharynx discomfort and surgical satisfaction. Conclusion: In the OSAHS patients with anterior and posterior pharyngeal stenosis, the effect of UPF was better than that of UPPP among the indexes of scar formation, pharyngeal symptoms and surgical satisfaction.

[Effects of functional training combined with self-made hand flexing training band in treatment of scar contracture after burn injury of dorsal hand].

Objective: To observe the effects of functional training combined with self-made hand flexing training band in treatment of scar contracture after burn injury of dorsal hand. Methods: Forty-six patients with scar contracture after deep partial-thickness or full-thickness burn injury of dorsal hand hospitalized in our department from March 2013 to February 2015 were divided into routine training group (RT, n=18) and comprehensive training group (CT, n=28) according to their willingness. Two weeks after the wounds were healed, patients in group RT were treated with functional training of hands and self-made pressure gloves, while patients in group CT were treated with self-made hand flexing training band (consisting of nylon strap, flexing band, and velcro) on the basis of those in group RT. All patients were treated for 3 months. Before and after treatment, scar condition of affected hands was assessed with Vancouver Scar Scale (VSS). The range of motion of joints of affected hands was measured by Total Active Movement (TAM) Scale. The function of affected hands was evaluated by Carroll Upper Extremity Function Test. Data were processed with t test, chi-square test, and Mann-Whitney U test. Results: (1) The score of VSS in patients of group RT was (10.0±1.9) points before treatment and (4.4±1.4) points after treatment, with the improved score of (5.6±1.0) points. The score of VSS in patients of group CT was (10.5±1.8) points before treatment and (4.6±1.4) points after treatment, with the improved score of (5.9±1.2) points. There was no statistically significant difference in the improved score of patients between the two groups (t=0.834, P>0.05). The score of VSS in patients of groups RT and CT after treatment was significantly lower than that before treatment (with t values respectively 14.014 and 10.003, P values below 0.01). (2) Before treatment, the ratios of excellent and good results according to TAM were 2/9 in patients of group RT and 3/14 in group CT, with no statistical differences between them (χ(2)=2.140, P>0.05). After treatment, the ratio of excellent and good results according to TAM in patients of group CT (6/7) was higher than that in group RT (5/9, χ(2)=0.023, P=0.038). The ratios of excellent and good results according to TAM in patients of groups RT and CT after treatment were significantly higher than those before treatment (with Z values respectively -2.023 and -4.780, P values below 0.05). (3) The improved score of hand function in patients of group CT was (26±12) points, which was higher than (15±7) points in group RT (t=3.278, P=0.002). The score of hand function in patients of groups RT and CT after treatment was significantly higher than that before treatment (with t values respectively 2.628 and 6.125, P values below 0.05). There were no significant differences in grades of hand function of patients between the two groups before treatment (Z=-0.286, P>0.05). After treatment, the grade of hand function in patients of group CT was higher than that in group RT(Z=-1.993, P=0.046). The grades of hand function in patients of groups RT and CT after treatment were significantly higher than those before treatment (with Z values respectively -2.717 and -4.998, P values below 0.01). Conclusions: For patients with scar contracture after burn injury of dorsal hand, early functional training combined with hand flexing training band can improve the range of motion of hand joints and functional recovery of hand, and the result was better than functional training alone.

Impact of human activities on subaqueous topographic change in Lingding Bay of the Pearl River estuary, China, during 1955-2013.

Estuaries have been sites of intensive human activities during the past century. Tracing the evolution of subaqueous topography in estuaries on a decadal timescale enables us to understand the effects of human activities on estuaries. Bathymetric data from 1955 to 2010 show that land reclamation decreased the subaqueous area of Lingding Bay, in the Pearl River estuary, by ~170 km2 and decreased its water volume by 615 × 106 m3, representing a net decrease of 11.2 × 106 m3 per year and indicating the deposition of approximately 14.5 Mt/yr of sediment in Lingding Bay during that period. Whereas Lingding Bay was mainly governed by natural processes with slight net deposition before 1980, subsequent dredging and large port engineering projects changed the subaqueous topography of the bay by shallowing its shoals and deepening its troughs. Between 2012 and 2013, continuous dredging and a surge of sand excavation resulted in local changes in water depth of ± 5 m/yr, far exceeding the magnitude of natural topographic evolution in Lingding Bay. Reclamation, dredging, and navigation-channel projects removed 8.4 Mt/yr of sediment from Lingding Bay, representing 29% of the sediment input to the bay, and these activities have increased recently.

crAssphage is not associated with diarrhoea and has high genetic diversity.

crAssphage is a newly discovered gut bacteriophage. However, its pathogenicity and molecular epidemiology in humans are as yet unclear. In this study, we investigated the association between crAssphage and diarrhoea, as well as the molecular epidemiology of crAssphage in Chinese patients from our hospital. Our results indicated that there were no significant differences in the crAssphage-positive ratio and viral loads in faecal supernatants between adults with diarrhoea and healthy adults. Of infants and children with diarrhoea, 2·8% were found to be crAssphage-positive, including two infants aged <1 month. Markedly, of all confirmed crAssphage-positive strains, 100% had the ORF00039 deletion and 77·8% had low identity of ORF00018 compared to crAssphage (GenBank accession no. NC_024711, designated genotype 1). Thus, crAssphage was not associated with diarrhoea and most strains of crAssphage in Chinese patients (designated genotype 2) were characterized by the ORF00039 deletion and low identity of ORF00018.

Randomized clinical trial of autologous skin cell suspension combined with skin grafting for chronic wounds.

BACKGROUND: Treatment of chronic wounds using traditional surgical procedures is challenging because of the low graft take rates. This study investigated the combination approach of split-thickness autografts with harvested skin cell suspension for chronic wound treatment. METHODS: This randomized clinical trial enrolled patients with chronic wounds between March 2012 and December 2013. Patients who were assigned randomly to the active treatment received a split-thickness autograft combined with harvested skin cell suspension. Control patients received the split-thickness autograft alone. The primary outcome was the rate of complete wound closure by postoperative day 28. Analysis was by intention to treat. Patients who achieved wound closure were followed up for a minimum of 6 months to evaluate the quality of healing. RESULTS: A total of 88 patients were included, 44 in each group. More patients achieved complete wound closure in the skin cell group than in the control group (41 versus 34 patients; P = 0·035). Complete wound closure was observed at a median of 14 (95 per cent c.i. 12·0 to 16·0) days in the skin cell group and 20 (15·7 to 24·3) days in the control group (P = 0·001). The skin cell group had significantly fewer complications (4 versus 11 patients; P = 0·047). The autografted sites displayed better physical attributes and a reduced tendency for wound recurrence in the skin cell group. CONCLUSION: Complementary split-thickness autologous skin grafting with autologous skin cells harvested using ReCell® (Avita Medical, Cambridge, UK) technology improved the healing rate of chronic wounds. REGISTRATION NUMBER: UMIN000011966 (http://www.umin.ac.jp/ctr).

Expression of insulin-like growth factor-1 receptor in keloid and hypertrophic scar.

BACKGROUND: Keloid and hypertrophic scar (HS) are two pathological forms of excessive dermal fibrosis, which are due to aberrant wound-healing responses. Accumulating evidence suggests that aberrant activity of growth factors and increased numbers of growth factor receptors play an important role in the formation of pathological scar. AIM: We examined the expression level of insulin-like growth factor-1 receptor (IGF-IR) in keloid, HS and normal skin. METHODS: IGF-IR expression was analyzed by immunohistochemistry, real-time PCR and western blotting on tissues and fibroblasts from 30 patients, comprising 10 patients with keloid and 20 with HS (10 with immature and 10 with mature HS), and from 10 age-matched and sex-matched healthy controls. RESULTS: Immunoreactivity to IGF-IR was found in dermal fibroblasts of keloid (90%), immature HS, (80%) and mature HS (30%), but not in normal skin. There was no statistically significant difference in immunoreactivity scores between keloid and immature HS, but there was a significant difference (P < 0.01) between mature and immature HS. Real-time PCR and western blot analysis confirmed that there was high expression of IGF-IR in keloid and immature HS fibroblasts, but not in mature HS or normal skin fibroblasts. IGF-IR was expressed in the overlying epidermis, and there was no significant difference between the groups. CONCLUSIONS: IGF-IR may be involved in the pathogenesis of keloid and HS. Given that IGF-IR are predominantly expressed on dermal fibroblasts, targeting of IGF-IR in fibroblasts may be of benefit to prevent scarring.

Efficacy of tension-free vaginal tape obturator and single-incision tension-free vaginal tape-Secur, hammock approach, in the treatment of stress urinary incontinence.

AIM: Aim of the present study was to compare the efficacy of tension-free vaginal tape obturator and single-incision tension-free transvaginal tape Secur, hammock approach, in the treatment of stress urinary incontinence. METHODS: Clinical data of patients who received anti-incontinence surgery between June 2008 and July 2012 were retrospectively analyzed. Efficacy and early failure rate of the tension-free vaginal tape obturator and tension-free vaginal tape-Secur hammock approach were assessed by cough test and criteria of International Consultation on Incontinence Questionnaire-Short Form. Intraoperative and postoperative complications were also computed. RESULTS: There were 28 patients in the tension-free vaginal tape obturator group while 32 patients in the tension-free vaginal tape-Secur group. The mean operation time, intraoperative blood loss and inpatient days after surgery between the two groups showed no significant difference. The catheter retention time of the tension-free vaginal tape obturator group was longer than in the tension-free vaginal tape-Secur group. The cure rate of the tension-free vaginal tape obturator and tension-free vaginal tape-Secur groups were respectively 84% and 80%, and the recurrence rates were 14.3% and 16.7%, without significant difference. The scores of International Consultation on Incontinence Questionnaire-Short Form in two groups both decreased after surgery, but there was no difference between the two groups. There were no serious complications in the two groups. CONCLUSION: Our study demonstrated that both tension-free vaginal tape obturator and tension-free vaginal tape-Secur can achieve a cure rate over 80% while with little complications, showing both methods are reliable to treat stress urinary incontinence.

Serum-dependent processing of late apoptotic cells for enhanced efferocytosis.

Binding of the serum protein complement component C1q to the surface of dying cells facilitates their clearance by phagocytes in a process termed efferocytosis. Here, we investigate during which phase of apoptotic cell death progression C1q binding takes place. Purified C1q was found to bind to all dying cells and, albeit weaker, also to viable cells. The presence of serum abrogated completely the binding to viable cells. In addition, C1q binding to dying cells was limited to a specific subpopulation of late apoptotic/secondary necrotic cells. Co-culturing serum-treated apoptotic cells with human monocytes revealed a much higher phagocytosis of C1q-positive than of C1q-negative late apoptotic/secondary necrotic cells. But this phagocytosis-promoting activity could not be observed with purified C1q. Serum-treated C1q-positive late apoptotic/secondary necrotic cells exhibited a similar volume, a similar degraded protein composition, but a much lower DNA content in comparison with the remaining late apoptotic/secondary necrotic cells. This was mediated by a serum-bound nuclease activity that could be abrogated by G-actin, which is a specific inhibitor of serum DNase I. These results show that serum factors are involved in the prevention of C1q binding to viable cells and in the processing of late apoptotic/secondary necrotic cells promoting cell death progression toward apoptotic bodies. This process leads to the exposure of C1q-binding structures and facilitates efferocytosis.

Gate-controlled current and inelastic electron tunneling spectrum of benzene: a self-consistent study.

We use density functional theory based nonequilibrium Green's function to self-consistently study the current through the 1,4-benzenedithiol (BDT). The elastic and inelastic tunneling properties through this Au-BDT-Au molecular junction are simulated, respectively. For the elastic tunneling case, it is found that the current through the tilted molecule can be modulated effectively by the external gate field, which is perpendicular to the phenyl ring. The gate voltage amplification comes from the modulation of the interaction between the electrodes and the molecules in the junctions. For the inelastic case, the electron tunneling scattered by the molecular vibrational modes is considered within the self-consistent Born approximation scheme, and the inelastic electron tunneling spectrum is calculated.

In vitro development of vitrified buffalo oocytes following parthenogenetic activation and intracytoplasmic sperm injection.

The objective of this study was to investigate the potential of swamp buffalo oocytes vitrified-warmed at the metaphase of the second meiotic cell division (M-II) stage to develop to the blastocyst stage after parthenogenetic activation (PA) or intracytoplasmic sperm injection (ICSI). In Experiment 1, we examined the effects of exposure time of oocytes to cryoprotectants (CPA) on their in vitro development after PA. In vitro matured (IVM) oocytes were placed in 10% dimethylsulfoxide (DMSO) + 10% ethylene glycol (EG) for 1 min and then exposed to 20% DMSO + 20% EG + 0.5 M sucrose for 30 s, 45 s or 60 s (1 min + 30 s, 1 min + 45 s and 1 min + 60 s groups, respectively). The oocytes were then exposed to warming solution (TCM199 HEPES + 20% FBS and 0.5M sucrose) for 5 min and then washed in TCM199 HEPES + 20% FBS for 5 min. IVM oocytes without CPA treatments served as a control group. The viability assessed by fluorescein diacetate (FDA) staining was 100% in all groups. The developmental rates after PA to the blastocyst stage between 1min+30s (16%) and control (26%) groups did not differ significantly, but they were significantly higher than those in 1 min + 45 s (10%) and 1 min + 60 s (2%) groups. In Experiment 2, we examined the effect of two CPA exposure times, 1 min + 30 s and 1 min + 45 s on the in vitro development after PA of oocytes vitrified by the microdrop method. The viabilities in vitrified 1 min + 30 s, 1 min + 45 s and the control (without CPA treatments) groups were not different (97%, 95% and 100%, respectively). The development of surviving oocytes to the blastocyst stage in the vitrified 1 min + 30 s group (8%) was significantly higher than that in the vitrified 1 min + 45 s group (4%) and significantly lower than those in control group (26%). In Experiment 3, we examined the effect of two CPA exposure times, 1 min + 30 s and 1 min + 45 s on in vitro development after ICSI of vitrified oocytes. Viabilities in vitrified oocytes among 1 min + 30 s, 1 min + 45 s and control groups were not different (96%, 91% and 100%, respectively). After ICSI, vitrified-warmed oocytes were activated and oocytes with the second polar body were cultured for 7 days. The development of ICSI oocytes to the blastocyst stage in the vitrified 1 min + 30 s group (11%) was significantly higher than that in the vitrified 1 min + 45 s (7%) group and significantly lower than those in control group (23%). In conclusion, our study demonstrated that the 1 min + 30 s CPA treatment regimen could yield the highest blastocyst formation rates after PA and ICSI for oocytes vitrified by the microdrop method.

Effects of chemical activation treatment on development of swamp buffalo (Bubalus bubalis) oocytes matured in vitro and fertilized by intracytoplasmic sperm injection.

The objective of this study was to optimize the activation protocol for buffalo oocytes after intracytoplasmic sperm injection (ICSI). The release of the second polar body (PB) at 3, 6 and 9 h after ICSI of in-vitro matured oocytes activated either with 5 µm ionomycin (Io) or with 7% ethanol (EtOH) was preliminary examined. The highest rate of second PB extrusion occurred at 3 h of activation, and the second PB extrusion in EtOH group was significantly higher than that in Io group. Oocytes that extruded the second PB were selected and cultured either with 1.9 mm 6-dimethylaminopurine (6-DMAP) for 3 h or with 10 µg/ml cycloheximide (CHX) for 5 h. Significantly higher rate of oocytes formed 2 pronuclei in EtOH combined with CHX (EtOH + CHX) (62%) group compared to those of Io + CHX (42%) and EtOH + 6-DMAP (48%) groups (p<0.01) whereas Io + 6-DMAP group showed intermediate value (58%). Significantly higher blastocyst formation rates were obtained in Io + 6-DMAP (29%) and EtOH + CHX (24%) groups than in Io + CHX (6%) and EtOH + 6-DMAP (17%) groups. Our results indicate that buffalo ICSI oocytes are effectively activated by combination treatment of Io with 6-DMAP and EtOH with CHX resulting in the highest cleavage and blastocyst formation rates.

Polarization-induced switching effect in graphene nanoribbon edge-defect junction.

With nonequilibrium Green's function approach combined with density functional theory, we perform an ab initio calculation to investigate transport properties of graphene nanoribbon (GNR) junctions self-consistently. Tight-binding approximation is applied to model the zigzag (ZGNR) electrodes, and its validity is confirmed in comparison to the GAUSSIAN03 periodic boundary condition calculation result of the same system. The origin of abnormal jump points usually appearing in the transmission spectrum is explained with the detailed tight-binding ZGNR band structure. Transport property of an edge-defect ZGNR junction is investigated, and the tunable tunneling current can be sensitively controlled by transverse electric fields.

Current through single conjugated molecules: calculations versus measurements.

We use density functional theory based nonequilibrium Green's function to calculate the current through the different rodlike molecules at the finite temperatures self-consistently, which was compared to the experimental measurements presented by Reichert et al. [Phys. Rev. Lett. 88, 176804 (2002)] and by Mayor et al. [Angew. Chem. Int. Ed. 42, 5834 (2003)], respectively. Our results agree with the measurements very well, especially for the bias around +/-1.0 V. The investigation of the topological effect for the symmetrical molecule reveals the fact that the para position compound provides a considerably larger conductance than the meta one.