A multicenter, randomized controlled study on the efficacy of agomelatine in ameliorating anhedonia, reduced motivation, and circadian rhythm disruptions in patients with major depressive disorder (MDD).

OBJECTIVE: To evaluate the clinical efficacy and safety of Agomelatine in improving symptoms in patients with major depressive disorder (MDD), providing more scientific evidence for the treatment of depression, and offering more effective therapeutic options for patients. METHODS: A total of 180 MDD patients in acute phase from 10 psychiatric hospitals of Grade three in Zhejiang Province were enrolled in this 12-week study with the competitive and consecutive pattern, and they were randomized into two different groups treated with flexible-dosage antidepressants of selective serotonin reuptake inhibitors (SSRI) or agomelatine, respectively. The subjects were evaluated with psychological scales of HAMD-17, HAMA, SHAPS for anhedonia, MFI-20 for fatigue, PQSI for sleep quality and MEQ for disturbances in chronobiologic rhythms at baseline, 2, 4, 8 and 12-weekend points, and TESS was used for side-effect. The results were analyzed with repeated measurement analysis of variance. RESULTS: The two groups each had 90 participants, and there were no significant differences at baseline. The scores of various assessment scales showed statistically significant time main effects during the visits (P < 0.01). The Agomelatine group demonstrated faster efficacy within 2 weeks, with better improvement in SHAPS, MEQ, and PSQI compared to the SSRIs group. However, the remission rate at 12 weeks was lower in the Agomelatine group than in the SSRIs group (63.3% and 72.2%), but the difference between the groups was not statistically significant. The Agomelatine group had fewer adverse reactions (14.4% and 16.7%), but there was a slightly higher incidence of liver function impairment (6.7% and 4.4%), with no statistically significant difference between the groups. CONCLUSION: Agomelatine, as a novel antidepressant, shows certain advantages in improving depression and anxiety symptoms and is comparable to SSRIs in terms of safety. However, its long-term efficacy and safety on MDD or other depressive subtypes still require further observation and research.

Effects of chronotype on antidepressant treatment and symptoms in patients with depression: a multicenter, parallel, controlled study.

AIM: To analyze the changes of chronotypes in patients with depression before and after treatment, and explore the effects of different chronotypes on antidepressant treatment and the dimensions of common symptoms in patients with depression. METHODS: 180 patients with depression were selected from 10 tertiary psychiatric hospitals in Zhejiang province, according to the scores of morningness-eveningness questionnaire (MEQ), the patients were divided into three groups: early-type group, middle-type group and late-type group. The 17-item Hamilton Depression Rating Scale (HAMD-17), Hamilton Anxiety Rating Scale anxiety Scale (HAMA), Snaith Hamilton Pleasure Scale (SHAPS), multidimensional fatigue inventory-20(MFI-20) and Pittsburgh sleep quality index (PSQI) were measured at baseline and at the end of the 2nd, 4th, 8th and 12th weeks, the variance analysis of repeated measures was used to analyze the change of each index in the study. The remission rate of depression at each time point was statistically analyzed. RESULTS: Of the 180 patients included in the study, 26 were lost to follow-up, and 154 were finally included in the analysis. At baseline, 14.93%, 56.5% and 28.57% of the subjects were diagnosed as middle-late type, middle-late type and early-late type respectively, the total scores of Shaps and MFI-20 in the early-type group were higher than those in the late-type group and the middle-type group (p < 0.05). During the 12-week antidepressant treatment period, the time effect of PSQI, Shaps, MFI-20 and MEQ had interaction with different time groups (p < 0.05). During the treatment, the multiple symptom dimensions of depression were improved to different degrees, but the changing trend was not the same, and the recovery of the anhedonia was obviously delayed, in early-type patients, there are many symptoms such as loss of pleasure and sleep disorders. There was no significant effect on the remission rate of depression in different time type (p > 0.05) . CONCLUSION: The disorder of chronotypes is common in patients with depression. The time effect of different time type on different symptom dimension of depression was affected, but the effect on remission rate of depression was not significant. To strengthen the management of biological chronotype rhythm in patients with depression may be of great significance in the treatment of depression.

Smartphone addiction and victimization predicts sleep problems and depression among children.

BACKGROUND: In this study we examined the phenomena of smartphone addiction, online harassment, and school bullying/victimization to predict the prospective influence these could have on the onset and persistence of sleep problems and depression among children. METHODS: Responses from 2155 fifth-grade children recruited from 30 primary schools in Taipei were assessed, and a follow-up was performed in the 6th grade. Self-administered questionnaires were collected for each year. FINDINGS: Children who reported smartphone addictions, online harassment, and school bullying/victimization coupled with an increase in those factors were more likely to experience the onset and persistence of sleep problems. In addition, children who reported smartphone addiction, online harassment, school bullying/victimization, and poor sleep quality were more likely to experience the onset and persistence of depression. IMPLICATIONS: School nurses or pediatric nurses should be able to assess children's Internet use and risks to understand potential influences on sleep quality and mental status and provide recommendations for children, parents and schools.

Shortening Door-to-Needle Time by Multidisciplinary Collaboration and Workflow Optimization During the COVID-19 Pandemic.

OBJECTIVES: This study aims to evaluate shortening door-to-needle time of intravenous recombinant tissue plasminogen activator of acute ischemic stroke patients by multidisciplinary collaboration and workflow optimization based on our hospital resources. MATERIALS AND METHODS: We included patients undergoing thrombolysis with intravenous recombinant tissue plasminogen activator from January 1, 2018, to September 30, 2020. Patients were divided into pre- (January 1, 2018, to December 31, 2019) and post-intervention groups (January 1, 2020, to September 31, 2020). We conducted multi-department collaboration and process optimization by implementing 16 different measures in prehospital, in-hospital, and post-acute feedback stages for acute ischemic stroke patients treated with intravenous thrombolysis. A comparison of outcomes between both groups was analyzed. RESULTS: Two hundred and sixty-three patients received intravenous recombinant tissue plasminogen activator in our hospital during the study period, with 128 and 135 patients receiving treatment in the pre-intervention and post-intervention groups, respectively. The median (interquartile range) door-to-needle time decreased significantly from 57.0 (45.3-77.8) min to 37.0 (29.0-49.0) min. Door-to-needle time was shortened to 32 min in the post-intervention period in the 3rd quarter of 2020. The door-to-needle times at the metrics of ≤ 30 min, ≤ 45 min, ≤ 60 min improved considerably, and the DNT> 60 min metric exhibited a significant reduction. CONCLUSIONS: A multidisciplinary collaboration and continuous process optimization can result in overall shortened door-to-needle despite the challenges incurred by the COVID-19 pandemic.

A Damping Grid Strapdown Inertial Navigation System Based on a Kalman Filter for Ships in Polar Regions.

The grid strapdown inertial navigation system (SINS) used in polar navigation also includes three kinds of periodic oscillation errors as common SINS are based on a geographic coordinate system. Aiming ships which have the external information to conduct a system reset regularly, suppressing the Schuler periodic oscillation is an effective way to enhance navigation accuracy. The Kalman filter based on the grid SINS error model which applies to the ship is established in this paper. The errors of grid-level attitude angles can be accurately estimated when the external velocity contains constant error, and then correcting the errors of the grid-level attitude angles through feedback correction can effectively dampen the Schuler periodic oscillation. The simulation results show that with the aid of external reference velocity, the proposed external level damping algorithm based on the Kalman filter can suppress the Schuler periodic oscillation effectively. Compared with the traditional external level damping algorithm based on the damping network, the algorithm proposed in this paper can reduce the overshoot errors when the state of grid SINS is switched from the non-damping state to the damping state, and this effectively improves the navigation accuracy of the system.

Laser gyro temperature compensation using modified RBFNN.

To overcome the effect of temperature on laser gyro zero bias and to stabilize the laser gyro output, this study proposes a modified radial basis function neural network (RBFNN) based on a Kohonen network and an orthogonal least squares (OLS) algorithm. The modified method, which combines the pattern classification capability of the Kohonen network and the optimal choice capacity of OLS, avoids the random selection of RBFNN centers and improves the compensation accuracy of the RBFNN. It can quickly and accurately identify the effect of temperature on laser gyro zero bias. A number of comparable identification and compensation tests on a variety of temperature-changing situations are completed using the multiple linear regression (MLR), RBFNN and modified RBFNN methods. The test results based on several sets of gyro output in constant and changing temperature conditions demonstrate that the proposed method is able to overcome the effect of randomly selected RBFNN centers. The running time of the method is about 60 s shorter than that of traditional RBFNN under the same test conditions, which suggests that the calculations are reduced. Meanwhile, the compensated gyro output accuracy using the modified method is about 7.0 × 10-4 °/h; comparatively, the traditional RBFNN is about 9.0 × 10-4 °/h and the MLR is about 1.4 × 10-3 °/h.

[Correlation analysis of cement leakage with volume ratio of intravertebral bone cement to vertebral body and vertebral body wall incompetence in percutaneous vertebroplasty for osteoporotic vertebral compression fractures].

OBJECTIVE: To investigate the risk factors of cement leakage in percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fracture (OVCF). METHODS: Between March 2011 and March 2012, 98 patients with single level OVCF were treated by PVP, and the clinical data were analyzed retrospectively. There were 13 males and 85 females, with a mean age of 77.2 years (range, 54-95 years). The mean disease duration was 43 days (range, 15-120 days), and the mean T score of bone mineral density (BMD) was -3.8 (range, -6.7- -2.5). Bilateral transpedicular approach was used in all the patients. The patients were divided into cement leakage group and no cement leakage group by occurrence of cement leakage based on postoperative CT. Single factor analysis was used to analyze the difference between 2 groups in T score of BMD, operative level, preoperative anterior compression degree of operative vertebrae, preoperative middle compression degree of operative vertebrae, preoperative sagittal Cobb angle of operative vertebrae, preoperative vertebral body wall incompetence, cement volume, and volume ratio of intravertebral bone cement to vertebral body. All relevant factors were introduced to logistic regression analysis to analyze the risk factors of cement leakage. RESULTS: All procedures were performed successfully. The mean operation time was 40 minutes (range, 30-50 minutes), and the mean volume ratio of intravertebral bone cement to vertebral body was 24.88% (range, 7.84%-38.99%). Back pain was alleviated significantly in all the patients postoperatively. All patients were followed up with a mean time of 8 months (range, 6-12 months). Cement leakage occurred in 49 patients. Single factor analysis showed that there were significant differences in the volume ratio of intravertebral bone cement to vertebral body and preoperative vertebral body wall incompetence between 2 groups (P < 0.05), while no significant difference in T score of BMD, operative level, preoperative anterior compression degree of operative vertebrae, preoperative middle compression degree of operative vertebrae, preoperative sagittal Cobb angle of operative vertebrae, and cement volume (P > 0.05). The logistic regression analysis showed that the volume ratio of intravertebral bone cement to vertebral body (P < 0.05) and vertebral body wall incompetence (P < 0.05) were the risk factors for occurrence of cement leakage. CONCLUSION: The volume ratio of intravertebral bone cement to vertebral body and vertebral body wall incompetence are risk factors of cement leakage in PVP for OVCF. Cement leakage is easy to occur in operative level with vertebral body wall incompetence and high volume ratio of intravertebral bone cement to vertebral body.

Expression of FSH and its co-localization with FSH receptor and GnRH receptor in rat cerebellar cortex.

The expression of follicle-stimulating hormone (FSH) and its receptor in extrapituitary and non-HPG axis tissues has been demonstrated and their non-reproductive functions in these tissues have been found. However, there have been no reports concerning the expression and function of FSH and its receptor in the cerebellum. In our study, immunofluorescence staining and in situ hybridization were used to detect the expression of FSH, double-labeled immunofluorescence staining was used to detect co-localization of FSH and its receptor and co-localization of FSH and gonadotropin-releasing hormone (GnRH) receptor in the rat cerebellar cortex. Results showed that some cells of the Purkinje cell layer, granular layer, and molecular layer of the cerebellar cortex showed both FSH immunoreactivity and FSH mRNA positive signals; not only for FSH and FSH receptor, but also for FSH and GnRH receptor co-localized in some cells throughout the Purkinje cell layer, granular layer, and molecular layer of the cerebellar cortex. These suggested that rat cerebellum could express FSH; cerebellum is a target tissue of FSH; FSH may exert certain functions through FSH receptor in a paracrine or autocrine manner; GnRH may regulate FSH positive cells through GnRH receptor in the cerebellum. Our study provides morphological evidence for further functional research on FSH and related hormones in the cerebellum.

[In-vivo and ex-vivo studies on region-specific remodeling of large elastic arteries due to simulated weightlessness and its prevention by gravity-based countermeasure].

The present study was designed to test the hypothesis that a medium-term simulated microgravity can induce region-specific remodeling in large elastic arteries with their innermost smooth muscle (SM) layers being most profoundly affected. The second purpose was to examine whether these changes can be prevented by a simulated intermittent artificial gravity (IAG). The third purpose was to elucidate whether vascular local renin-angiotensin system (L-RAS) plays an important role in the regional vascular remodeling and its prevention by the gravity-based countermeasure. This study consisted of two interconnected series of in-vivo and ex-vivo experiments. In the in-vivo experiments, the tail-suspended, hindlimb unloaded rat model was used to simulate microgravity-induced cardiovascular deconditioning for 28 days (SUS group); and during the simulation period, another group was subjected to daily 1-hour dorso-ventral (-G(x)) gravitation provided by restoring to normal standing posture (S + D group). The activity of vascular L-RAS was evaluated by examining the gene and protein expression of angiotensinogen (Ao) and angiotensin II receptor type 1 (AT1R) in the arterial wall tissue. The results showed that SUS induced an increase in the media thickness of the common carotid artery due to hypertrophy of the four SM layers and a decrease in the total cross-sectional area of the nine SM layers of the abdominal aorta without significant change in its media thickness. And for both arteries, the most prominent changes were in the innermost SM layers. Immunohistochemistry and in situ hybridization revealed that SUS induced an up- and down-regulation of Ao and AT1R expression in the vessel wall of common carotid artery and abdominal aorta, respectively, which was further confirmed by Western blot analysis and real time PCR analysis. Daily 1-hour restoring to normal standing posture over 28 days fully prevented these remodeling and L-RAS changes in the large elastic arteries that might occur due to SUS alone. In the ex-vivo experiments, to elucidate the important role of transmural pressure in vascular regional remodeling and differential regulation of L-RAS activity, we established an organ culture system in which rat common carotid artery, held at in-vivo length, can be perfused and pressurized at varied flow and pressure for 7 days. In arteries perfused at a flow rate of 7.9 mL/min and pressurized at 150 mmHg, but not at 0 or 80 mmHg, for 3 days led to an augmentation of c-fibronectin (c-FN) expression, which was also more markedly expressed in the innermost SM layers, and an increase in Ang II production detected in the perfusion fluid. However, the enhanced c-FN expression and increased Ang II production that might occur due to a sustained high perfusion pressure alone were fully prevented by daily restoration to 0 or 80 mmHg for a short duration. These findings from in-vivo and ex-vivo experiments have provided evidence supporting our hypothesis that redistribution of transmural pressures might be the primary factor that initiates region-specific remodeling of arteries during microgravity and the mechanism of IAG is associated with an intermittent restoration of the transmural pressures to their normal distribution. And they also provide support to the hypothesis that L-RAS plays an important role in vascular adaptation to microgravity and its prevention by the IAG countermeasure.

A study on expression of FSH and its effects on the secretion of insulin and glucagon in rat pancreas.

Studies indicate that many tissues could express follicle-stimulating hormone (FSH) besides pituitary. New functions of FSH are also been recognized beyond reproduction regulation. However, no report has been made about the expression and function of FSH in rat pancreas yet. Dual-labeled immunofluorescence stain, in situ hybridization and dual-labeled immunohistochemistry stain in adjacent sections were used to study the expression of FSH and its receptor, and co-localization of FSH with gonadotropin-releasing hormone (GnRH) receptor in rat pancreas. Tissue incubation and enzyme-linked immunosorbant assay (ELISA) were used to study the effects of FSH on the secretion of insulin and glucagon in rat pancreas in vitro. The results showed that rat pancreas could express FSH and its receptor, some of islet cells co-expressed FSH and its receptor, some of islet cells co-expressed FSH and GnRH receptor. FSH has the same bidirectional regulation effects on insulin and glucagon in vitro. These data suggested that rat pancreas is a target organ of FSH, and GnRH might regulate FSH through GnRH receptor in rat pancreas. FSH might regulate the endocrine function of rat pancreas through FSH receptor.

GnRH analogue attenuated apoptosis of rat hippocampal neuron after ischemia-reperfusion injury.

The expression and new functions of reproductive hormones in organs beyond hypothalamus-pituitary-gonad axis have been reported. So far, there is no report about the protective effects of GnRH analogue to hippocampal neurons suffering from ischemia-reperfusion injury. Middle cerebral artery occlusion model together with TUNEL staining were made in vivo and oxygen-glucose deprivation model together with double staining of Annexin V/PI with flow cytometer were made in vitro to observe the anti-apoptotic effects of GnRH analogue to hippocampal neurons after ischemia-reperfusion injury. The results found that the number of TUNEL positive pyramidal neurons in CA1 region in GnRH analogue experiment group was less than that in control group in vivo; the percentage of apoptotic neurons in GnRH analogue experiment group was less than that in control group in vitro. These findings suggested that pretreatment with certain concentration of GnRH analogue could attenuate apoptosis of hippocampal neurons. GnRH analogue has the protective effects to neurons.

Studies on expression of FSH and its anti-apoptotic effects on ischemia injury in rat spinal cord.

Studies indicated that many tissues could express FSH. New functions of FSH have been recognized beyond reproduction regulation. However, no report has been made about the expression and function of FSH in rat spinal cord. Double-labeled immunofluorescence stain and in situ hybridization were used to study the co-localization of FSH with its receptor and co-localization of FSH with GnRH receptor in rat spinal cord. Spinal cord ischemia injury models were built, TUNEL stain and Fas immunostaining were made to observe the anti-apoptotic effects of FSH to neurons induced by spinal cord ischemia injury. The results found that some neurons and glias of rat spinal cord showed both FSH immunoreactivity and FSH mRNA positive signals; not only FSH and its receptor but also FSH and GnRH receptor co-located in cells of both gray matter and white matter; treatment with certain concentration of FSH before ischemia-reperfusion injury, less TUNEL positive cells and Fas positive cells were found in motor neurons of ventral gray matter in FSH experiment group than that in control group. These suggested that rat spinal cord could express FSH, it is also a target organ of FSH; FSH might exert functions through its receptor by paracrine or autocrine effects; GnRH in spinal cord might regulate FSH positive neurons through GnRH receptor; FSH might inhibit ischemia induced neuron apoptosis by down-regulating Fas expression in spinal cord.

Production of an anti-idiotypic antibody single chain variable fragment vaccine against Edwardsiella tarda.

Edwardsiella tarda is the pathogen responsible for edwardsiellosis, a serious infectious disease of freshwater and marine fish species, and currently recognized to be the species pathogenic for human. An anti-idiotypic monoclonal antibody (mAb), 1E11, has been developed. It mimics the protective epitope of E. tarda and can prevent fish from infection of E. tarda. In this study, the correct variable heavy (VH) and variable light (VL) genes were obtained from 1E11 by using bioinformatics methods, and a 15 amino acid (Gly4Ser)3 linker was used to hold the two V domains together for the construction of VL-linker-VH form of single chain variable fragment (scFv) gene. Then, the scFv was subcloned into the vector pET-28a, expressed in the Escherichia coli BL21 cells, and identified by SDS-PAGE and western blotting. Red drum (Sciaenops ocellatus L.) weighing about 50 g was subjected to challenge with different E. tarda strains after 4 weeks followed by vaccination, the mortality rates and relative percentage survival were recorded and calculated, and the survival rate of fish in the scFv subgroups was obviously higher than that of control subgroups (P<0.01). Enzyme-linked immunosorbent assay results show that after 4 weeks of post-vaccination, the level of specific antibody in fish sera of scFv groups was significantly higher than control groups. This study indicates that the recombinant antibody scFv was successfully developed, and it may serve as an effective vaccine candidate against E. tarda.

Localization and expression of peroxiredoxin II in the mouse ovary, oviduct, uterus, and preimplantation embryo.

Peroxiredoxin (Prx) II belongs to a recently discovered family of peroxidases that play important roles in antioxidation and signal transduction. In this study, we aimed to study the localization and expression of Prx II in the mouse ovary, oviduct, and uterus, and preimplantation embryos. Immunohistochemical staining analysis showed that, in the ovary, Prx II was expressed in the oocyte cytoplasm of the primary follicle, the secondary follicle, and the premature follicle; Prx II was expressed in germinal vesicle-intact oocytes (GV oocytes) and metaphase II eggs (MII eggs), as well as at various stages in early embryos. Reverse transcription polymerase chain reaction (RT-PCR) results indicated that the Prx II mRNA was expressed at a high level in GV eggs, slightly lower levels in MII eggs, and had no detectable expression in four-cell embryos and early blastocysts. In the oviduct, Prx II was expressed in the epithelia, while in the uterus Prx II was mainly distributed in the endometrial stroma. Taken together, our results suggest that Prx II plays a key antioxidation role in the maturation of oocytes and development of early embryos, thus providing crucial experimental evidence for further exploring the function of Prx II in the development of oocytes and preimplantation embryos.

Ischemia-reperfusion injury effects a change in expression of GnRH and its receptor in CA1 neurons in rat hippocampus.

Many researches on the change and protective effects of estrogen and its receptor in hippocampus with ischemia-reperfusion injury have been done in recent years; the study on the change of GnRH and its receptor in hippocampus with ischemia-reperfusion injury has not been seen yet. This study used immunohistochemistry and in situ hybridization method, together with an image analysis system to observe the change in expression of GnRH and its receptor in hippocampus with ischemia-reperfusion injury. The study found that the expression of GnRH and GnRH mRNA and the number of positive cells decreased with time after damage. Expression of GnRH receptor and GnRH receptor mRNA in single positive cell early increased and later decreased after injury; the number of positive cells decreased with time after injury. Three days after injury, rare GnRH, GnRHR immunoreactive positive cells and cells with GnRH mRNA, GnRHR mRNA hybridization signal could be found in the stratum pyramida of CA1 region, many cells with weak GnRH, GnRH receptor immunoreactivity and weak GnRH mRNA, GnRH receptor mRNA hybridization signal appeared at stratum oriens and stratum radiatum. These suggested that GnRH may participate in the regulation of ischemia-reperfusion injury in CA1 region and repair of brain tissue.

A study on co-localization of FSH and its receptor in rat hippocampus.

It has been known that GnRH, LH and their receptors exist in hippocampal neurons. However, whether FSH and its receptor also exist in hippocampal neurons remained unknown yet. In situ hybridization, double-labeled immunofluorescence stain and double-labeled immunohistochemistry stain in adjacent sections were used in our research to study the distribution, co-localization of FSH and its receptor and co-localization of FSH and GnRH receptor in rat hippocampus. The result found that pyramidal neurons from CA1 to CA4 region and granule neurons in dentate gyrus could express FSH and its receptor, majority of hippocampal neurons co-expressed FSH and its receptor, FSH and GnRH receptor. These suggested that hippocampal neurons not only express FSH but also act as FSH target cells. FSH may regulate the function of hippocampal neurons by ways of paracrine or autocrine. At the same time, GnRH may regulate the function of FSH neuron in hippocampus through GnRH receptor.

[Chronic blockade of angiotensin II type 1 receptor cannot completely prevent structural adaptation in vessels of simulated weightless rats].

Our previous studies suggest that the vascular local renin-angiotensin system (L-RAS) plays a pivotal role in the region-specific vascular adaptation due to simulated weightlessness. The present study was designed to determine whether simulated weightlessness still induced adaptive changes in rat vessels when angiotensin II type 1 receptor (AT(1)R) was chronically blocked by the administration of losartan, and whether the expressions of key elements in the L-RAS in the large arteries would change. Tail suspension for 4 weeks was used to simulate the physiological effect of weightlessness. The responses of the basilar, anterior tibial, carotid arteries and abdominal aorta were observed by morphometric technique with light microscopy. The expressions of angiotensinogen (AGT) and AT(1)R in the walls of common carotid artery and abdominal aorta were determined using immunohistochemical technique. The results showed that simulated weightlessness induced hypertrophy of the media of basilar artery and smooth muscle layers of carotid artery, but atrophic change in the anterior tibial artery and abdominal aorta. After 4 weeks of losartan treatment, all these arteries showed significant atrophic changes. However, simulated weightlessness still induced relative hypertrophy of the basilar artery and carotid artery and atrophy of the abdominal aorta when AT(1)R was blocked. After 4 weeks of simulated weightlessness, the expressions of AGT and AT(1)R were upregualted in the wall of carotid artery, but downregulated in the wall of abdominal aorta and perivascular tissues. Losartan decreased AGT and AT(1)R expressions only in the wall of abdominal aorta; whereas simulated weightlessness further decreased AT(1)R expression in the wall of abdominal aorta when AT(1)R was blocked. We conclude that simulated weightlessness for 4 weeks still induces structural changes and upregulates or downregulates the key elements in L-RAS in the large and medium-sized arteries from fore and hind body parts of rats when AT(1)R is blocked. The results suggest that the L-RAS in arterial tissue plays a pivotal role in these differential structural changes. However, there still exist other regulatory pathways to mediate the adaptive regulation of cerebral vessels when AT(1)R is blocked.

Development of a phage displayed disulfide-stabilized Fv fragment vaccine against Vibrio anguillarum.

Anti-idiotype monoclonal antibody 1E10 can mimic the protective epitope of Vibrio anguillarum and be used as vaccine to prevent fish infection of V. anguillarum. In this study, the variable heavy (V(H)) domain and variable light (V(L)) domain of mAb1E10 were cloned by RT-PCR and were linked to each other by a disulfide bond engineered at position 44 of V(H) and position 105 of V(L) that lie between structurally conserved framework positions. Mutated V(H) 44 and V(L) 105 were inserted into phagemid pCANTAB5E. When co-transfected by recombinant pCANTAB5E and helper phage M13KO7, the host Escherichia coli cells secreted disulfide-stabilized Fv fragment (dsFv) which displayed on the surface of filamentous phage. The binding specificity of the phage-displayed dsFv was proved by ELISA method. Protection experiment showed that Japanese flounders can develop high titer of antibody against the dsFv and survival ratio of vaccinated group was significantly different from control groups. Thus, this phage-displayed dsFv may be used as vaccine against V. anguillarum in fishery.

[Cloning and sequence analysis of variable region gene of anti-idiotype monoclonal antibody against Vibrio alginolyticus].

AIM: To clone and sequence V(H) and V(L) genes of anti-idiotype monoclonal antibody (mAb) against vibrio alginolyticus. METHODS: Total RNA was extracted from hybridoma cell AL1 secreting mAb against vibrio alginolyticus and cDNA was amplified by RT-PCR. Then the cDNA was inserted into PMD18-T vector and its sequence was analyzed. RESULTS: The V(H) gene contained 369 bp and encoded 123 amino acid residues; the V(L) gene contained 339 bp and encoded 113 amino acid residues. There were four FRs, three CDRs and two characteristic cysteine residues in the V(H) and V(L) genes, respectively. CONCLUSION: The successful cloning of the V(H) and V(L) genes of anti-idiotype mAb against vibrio alginolyticus provides a sound basis for construction of gene-engineering vaccine of the anti-idiotype mAb against vibrio alginolyticus.

Distribution, cloning and sequencing of GnRH, its receptor, and effects of gastric acid secretion of GnRH analogue in gastric parietal cells of rats.

Our objective was to study the distribution of gonadotropin-releasing hormone (GnRH) and its receptor, cloning and sequencing of GnRH and its receptor gene in cultured gastric parietal cells of rats. The distribution of GnRH and its receptor mRNA were investigated through immunocytochemical ABC methods and in situ hybridization methods in cultured gastric parietal cells of rats. After isolation of the total RNA from the parietal cells, RT-PCR was conducted to obtain GnRH and its receptor cDNA. Then, the products of PCR was purified, digested by the restriction enzyme of Hind III and EcoR I, and DNA fragments of interests were cloned into pUC19 vector. The products of PCR were analyzed by sequencing with Sanger's method after identified by PCR and digestion of restriction enzyme. Gastric parietal cells showed GnRH and its receptor immunoreactivity; positive material was located in cytoplasm other than in nuclei. GnRH and its receptor mRNA hybridized signals were also detected in cytoplasm with negative nuclei. The specific amplified band of GnRH and its receptor sequences were detected through Agarose gel electrophoresis, and GnRH gene sequence is identical to that of GnRH which has been reported in rat hypothalamus and GnRH receptor sequence is identical to that of the pituitary of rat. GnRH analogue (Alarelin) could inhibit the gastric acid secretion both by direct actions on parietal cells and by inhibiting vagous function. Our data suggest that GnRH could be produced by gastric parietal cells of rats and may modulate physiological function of gastric parietal cells of rats through autocrinal and paracrinal way.