Relationship between Phenotypic Changes of Dendritic Cell Subsets and the Onset of Plateau Phase during Intermittent Interferon Therapy in Patients with CHB

Objective This study aimed to evaluate whether the onset of the plateau phase of slow hepatitis B surface antigen decline in patients with chronic hepatitis B treated with intermittent interferon therapy is related to the frequency of dendritic cell subsets and expression of the costimulatory molecules CD40,CD80,CD83,and CD86.Method This was a cross-sectional study in which patients were divided into a natural history group(namely NH group),a long-term oral nucleoside analogs treatment group(namely NA group),and a plateau-arriving group(namely P group).The percentage of plasmacytoid dendritic cell and myeloid dendritic cell subsets in peripheral blood lymphocytes and monocytes and the mean fluorescence intensity of their surface costimulatory molecules were detected using a flow cytometer.Results In total,143 patients were enrolled(NH group,n=49;NA group,n=47;P group,n=47).The results demonstrated that CD141/CD1c double negative myeloid dendritic cell(DNmDC)/lymphocytes and monocytes(%)in P group(0.041[0.024,0.069])was significantly lower than that in NH group(0.270[0.135,0.407])and NA group(0.273[0.150,0.443]),and CD86 mean fluorescence intensity of DNmDCs in P group(1832.0[1484.0,2793.0])was significantly lower than that in NH group(4316.0[2958.0,5169.0])and NA group(3299.0[2534.0,4371.0]),Adjusted P all<0.001.Conclusion Reduced DNmDCs and impaired maturation may be associated with the onset of the plateau phase during intermittent interferon therapy in patients with chronic hepatitis B.

Intermittent disturbance mechanical behavior and fractional deterioration mechanical model of rock under complex true triaxial stress paths

Mechanical excavation,blasting,adjacent rockburst and fracture slip that occur during mining excavation impose dynamic loads on the rock mass,leading to further fracture of damaged surrounding rock in three-dimensional high-stress and even causing disasters.Therefore,a novel complex true triaxial static-dynamic combined loading method reflecting underground excavation damage and then frequent intermittent disturbance failure is proposed.True triaxial static compression and intermittent disturbance tests are carried out on monzogabbro.The effects of intermediate principal stress and amplitude on the strength characteristics,deformation characteristics,failure characteristics,and precursors of monzogabbro are analyzed,intermediate principal stress and amplitude increase monzogabbro strength and tensile fracture mechanism.Rapid increases in microseismic parameters during rock loading can be precursors for intermittent rock disturbance.Based on the experimental result,the new damage fractional elements and method with considering crack initiation stress and crack unstable stress as initiation and acceleration condition of intermittent disturbance irreversible deformation are proposed.A novel three-dimensional disturbance fractional deterioration model considering the intermediate principal stress effect and intermittent disturbance damage effect is established,and the model predicted results align well with the experimental results.The sensitivity of stress states and model parameters is further explored,and the intermittent disturbance behaviors at different f are predicted.This study provides valuable theoretical bases for the stability analysis of deep mining engineering under dynamic loads.

Intermittent fasting boosts antitumor immunity by restricting CD11b^(+)Ly6C^(low)Ly6G^(low) cell viability through glucose metabolism in murine breast tumor model

Intermittent fasting can benefit breast cancer patients undergoing chemotherapy or immunotherapy.However,it is still uncertain how to select immunotherapy drugs to combine with intermittent fasting.Herein we observed that two cycles of fasting treatment significantly inhibited breast tumor growth and lung tissue metastasis,as well as prolonged overall survival in mice bearing 4T1 and 4T07 breast cancer.During this process,both the immunosuppressive monocytic-(M-)and granulocytic-(G-)myeloid-derived suppressor cell(MDSC)decreased,accompanied by an increase in interleukin(IL)7R^(+)and granzyme B^(+)T cells in the tumor microenvironment.Interestingly,we observed that Ly6G^(low)G-MDSC sharply decreased after fasting treatment,and the cell surface markers and protein mass spectrometry data showed potential therapeutic targets.Mechanistic investigation revealed that glucose metabolism restriction suppressed the splenic granulocytemonocyte progenitor and the generation of colony-stimulating factors and IL-6,which both contributed to the accumulation of G-MDSC.On the other hand,glucose metabolism restriction can directly induce the apoptosis of Ly6G^(low)G-MDSC,but not Ly6G^(high)subsets.In summary,these results suggest that glucose metabolism restriction induced by fasting treatment attenuates the immune-suppressive milieu and enhances the activation of CD3^(+)T cells,providing potential solutions for enhancing immune-based cancer interventions.

Intermittent sliding-lock-knot suture for limbal conjunctival autograft fixation in pterygium surgery:a technique note

AIM:To report a technique used with intermittent slidinglock-knot(ISLK)fixation for limbal conjunctival autografts in pterygium surgery and compared with those of routine intermittent(RI)fixation.METHODS:Consecutive patients with primary pterygium who had undergone pterygium excision combined with limbal conjunctival autograft transplantation between March 2021 and March 2022 at our institute were retrospectively analyzed.Primary outcome measures were mean duration of surgery and suture removal,degree of conjunctival hyperemia on postoperative day 1,pain score at suture removal,postoperative symptoms at 6mo,including conjunctival hyperemia,foreign body sensation,and graft stability.RESULTS:Ninety-eight patients underwent monocular surgery and were divided into ISLK(51 eyes)and RI(47 eyes)groups according to the type of conjunctiva autograft fixation method planned.There was no significant difference in mean duration of surgery between the two groups(18.59±2.39min vs 18.15±2.20min,P=0.417);however,compared to the RI group,shorter suture removal times were observed in the ISLK group[0.58min(0.42-0.87)vs 3.00min(2.21-4.15),P<0.001].The degree of conjunctival hyperemia on postoperative day 1 was milder in the ISLK group(P<0.001).Pain scores at suture removal were lower in the ISLK group than in RI group[1(0-3)vs 2(1-4),P<0.001].Postoperative symptoms at 6mo were comparable between the groups(P=0.487),with no recurrence.CONCLUSION:ISLK is an innovative method for limbal conjunctival autograft fixation after pterygium excision.Compared to RI fixation,ISLK facilitates suture removal and reduces discomfort,with comparable surgery duration and less conjunctival hyperemia.

Intermittent melena and refractory anemia due to jejunal cavernous lymphangioma:A case report

BACKGROUND Lymphangiomas in the gastrointestinal tract are extremely rare in adults.As a benign lesion,small intestine lymphangiomas often remain asymptomatic and pose challenges for definitive diagnosis.However,lymphangiomas can give rise to complications such as abdominal pain,bleeding,volvulus,and intussusception.Here,we report a case of jejunal cavernous lymphangioma that presented with intermittent melena and refractory anemia in a male adult.CASE SUMMARY A 66-year-old man presented with intermittent melena,fatigue and refractory anemia nine months prior.Esophagogastroduodenoscopy and colonoscopy were performed many times and revealed no apparent bleeding.Conservative management,including transfusion,hemostasis,gastric acid secretion inhibition and symptomatic treatment,was performed,but the lesions tended to recur shortly after surgery.Ultimately,the patient underwent capsule endoscopy,which revealed a more than 10 cm lesion accompanied by active bleeding.After singleballoon enteroscopy and biopsy,a diagnosis of jejunal cavernous lymphangioma was confirmed,and the patient underwent surgical resection.No complications or recurrences were observed postoperatively.CONCLUSION Jejunal cavernous lymphangioma should be considered a cause of obscure gastrointestinal bleeding.Capsule endoscopy and single-balloon enteroscopy can facilitate diagnosis.Surgical resection is an effective management method.

Comparative Analysis of Continuous versus Intermittent Proton Pump Inhibitor Therapy in Patients with Upper Gastrointestinal Bleeding Due to Ulcers

Upper gastrointestinal bleeding (UGIB) presents as a prevalent clinical challenge, with annual incidence rates ranging from 80 to 150 cases per 100,000 individuals. Guidelines for managing patients with UGIB due to bleeding ulcers recommend a continuous infusion of proton pump inhibitors (PPI). However, studies comparing intermittent dosing of PPI therapy show that this regimen achieves similar clinical benefits. If the clinical efficacy remains equivalent, intermittent dosing will be more cost-effective for patients and the health care system. Our research study aims to analyze the comparative effectiveness of intermittent versus continuous PPI therapy after endoscopic treatment in patients with UGIB, focusing on such endpoints as rebleeding risk at 3-and 7-day mortality rates. Methods: Resources searched included MEDLINE, EMBASE, PUBMED, and the Cochrane Central Register of Controlled Trials databases from January 2010 through December 2023 with the inclusion of meta-analysis, systematic review, review, or ACG guideline recommendations. Results of the analysis show how recommendations regarding high vs. low PPI regimen changed over time: from no difference in regimen in 2010 to recommending continuous regimen in 2012 to declaring insufficient evidence between choosing one regimen over another in 2013 to determine that both regimens were comparable to each other in 2014-2018 and finally to recommending both regimens in 2021. To conclude, our review shows that in patients with bleeding ulcers and high-risk endoscopic findings, intermittent PPI therapy is non-inferior to continuous PPI infusion for three days, seven days bleeding risk or mortality rates;however, it remains challenging to determine the most optimal intermittent regimen due to heterogeneity of RCTs included in meta-analyses, and further trials will need to be performed.

Low Birth Weight and Intermittent Preventive Treatment of Malaria in Pregnant Women in Lomé (Togo) in 2021: A Cross-Sectional Study

Background: Since 2012, the World Health Organization has recommended intermittent preventive treatment with sulfadoxine-pyrimethamine (IPT-SP) to prevent malaria-related complications in pregnant women. Ten years following these recommendations, we conducted this study to estimate the coverage for three doses of IPT-SP (IPT3) as well as the prevalence of low birth weight (LBW), and its associated factors in Lomé (Togo) in 2021. Methods: A cross-sectional study was conducted between January and March 2021. An exhaustive recruitment of women and their newborns was carried out in the maternity wards of the Sylvanus Olympio University Hospital Center. Data from antenatal consultations and clinical data of the newborns were collected. Multivariate logistic regression was carried out to determine factors associated with LBW. Results: A total of 252 mother-child pairs were included in this study. Median age of the mothers was 27 years, IQR [24-31]. More than a third (35.3%) of the mothers were primigravida. IPT3 coverage was 66.7% and 14.7% of newborns had a LBW. The prevalence of LBW was 33.3% [23.3-43.4] in women who had received fewer than 3 doses of IPT-SP and 5.4% [2.0-8.8] in those who had received at least 3 doses of IPT-SP (p Conclusion: Ten years following recommendations of the WHO on IPT-SP, malaria prevention based on IPT-SP is not optimal among pregnant women in Lomé, and the proportion of LBW children remains high. Actions to strengthen the three-dose IPT-SP policy are needed to prevent malaria and its consequences among newborns in Togo.

Passive Attack Detection for a Class of Stealthy Intermittent Integrity Attacks

This paper proposes a passive methodology for detecting a class of stealthy intermittent integrity attacks in cyberphysical systems subject to process disturbances and measurement noise.A stealthy intermittent integrity attack strategy is first proposed by modifying a zero-dynamics attack model.The stealthiness of the generated attacks is rigorously investigated under the condition that the adversary does not know precisely the system state values.In order to help detect such attacks,a backward-in-time detection residual is proposed based on an equivalent quantity of the system state change,due to the attack,at a time prior to the attack occurrence time.A key characteristic of this residual is that its magnitude increases every time a new attack occurs.To estimate this unknown residual,an optimal fixed-point smoother is proposed by minimizing a piece-wise linear quadratic cost function with a set of specifically designed weighting matrices.The smoother design guarantees robustness with respect to process disturbances and measurement noise,and is also able to maintain sensitivity as time progresses to intermittent integrity attack by resetting the covariance matrix based on the weighting matrices.The adaptive threshold is designed based on the estimated backward-in-time residual,and the attack detectability analysis is rigorously investigated to characterize quantitatively the class of attacks that can be detected by the proposed methodology.Finally,a simulation example is used to demonstrate the effectiveness of the developed methodology.

Study on Intermittent Discharge Characteristics of Typical Solid Insulation Defects in Gas Insulated Switchgear

In response to the problem of frequent leakage and false alarm of partial discharge insulation defects in GIS,this paper conducts experimental research on intermittent discharge characteristics of common solid insulation defects in GIS.Using true GIS to build amulti-source testing platform for intermittent discharge of solid insulation defects,and using pulse current method,ultra-high frequency method,ultrasonic method,and gas characteristic component detectionmethod to study the variation law of intermittent discharge characteristics of solid insulation defects.The results showthat:the intermittent discharge state of metal fouling defects on the solid insulation surface decreases with the extension of the discharge time,the discharge time interval as a whole shows an increasing trend,and the metal fouling defects on the solid insulation surface in the intermittent discharge state is difficult to develop into a breakdown discharge fault.The overall discharge amount of air gap defects inside solid insulation also shows the law of increasing first and then decreasing,and the discharge amount of air gap defects inside solid insulation stays at a large level for a long time during intermittent discharge,and there is a risk of breakdown,and the discharge will gradually evolve into continuous discharge;ultrasonic method and characteristic component detection method cannot realize the effective perception of intermittent discharge of metal fouling.The 50-period mapping information commonly used in the power field cannot reflect the intermittent discharge variation law of solid insulation,and the 200-period UHF mapping composed of four groups of 50-period UHF mapping data can initially derive the intermittent discharge distribution law of solid insulation defects.The research results of this paper are of great significance to expand the knowledge of intermittent discharge characteristics and the detection of GIS discharge defects in the field.

Research on Energy-Saving Performance of Intermittent Heating for Rooms in Hot Summer&ColdWinter Zone

In the hot summer&cold winter zone in China,intermittent heating space for rooms is widely used.However,in comparison with continuous space heating,the energy-saving performance of intermittent space heating has not been sufficiently investigated.This paper studied the factors influencing the energy performance of intermittent heating for the representativeoffice inhot summer&coldwinter zone.Basedon theheatbalancemethod,adynamic thermalmodel of the intermittent heating roomwas built and tested by experiments.And then,it analyzed the total space heating load,the amount of energy saving and energy saving ratio of the intermittent heating under different preheating hours,occupation hours,required roomtemperatures,air change rates,overall heat transfer coefficients(U-value)of windows and wall materials.If the adjacent rooms were not heated,for a typical room occupied about 10 h a day,the energy-saving ratio of intermittent heating was about 30%compared with continuous heating.But the preheating power was higher than two times of continuous heating.The results also indicated that the occupation hours had a significant effect on energy saving amount and ratio,it should be noted that the energy saving ratio by intermittent heating was much lower than the unoccupied period ratio.Relative to other factors,the heating temperatures,room air change rates and U-value of windows,and room envelope materials had little effect on energy efficiency.If the adjacent rooms were heated in the same manner as the roomin question,the energy-saving ratio of the total load of intermittent heating was heavily reduced to 8.46%.

Meta-analysis of the effects of high-intensity intermittent exercise on cardiopulmonary function rehabilitation in patients with stroke

Objective:Systematically evaluate the rehabilitation effect of high-intensity intermittent exercise(HIIT)on cardiovascular function in stroke patients,in order to provide a basis for selecting the best rehabilitation plan for stroke patients.Methods:Computer retrieval of CNKI,WanFang Data,VIP,CBM,Pubmed,EMbase,Web of science,The Cochrane Library databases was conducted from the establishment of the database until March 2023.Randomized controlled trials on HIIT improving cardiovascular function in stroke patients were included,and the included literature was screened,data extracted,and bias risk evaluated.Then,metaanalysis was conducted using RevMan 5.4 software and Stata17.0 software.Results:In the end,9 articles met the research criteria,with a total of 428 patients.The meta-analysis results showed that compared with the control group,HIIT had significant effects on peak oxygen uptake(VO2peak)[MD=3.87,95%CI(3.43,4.31),P<0.00001],minute ventilation(VE)[MD=7.14,95%CI(4.34,9.94),P<0.00001],peak power(WRpeak)[MD=17.13,95%CI(13.7320.54),P<0.00001],6-minute walking distance(6MWD)[MD=43.82,95%CI(16.08,71.56),P=0.002],The intervention effect of the 10 meter walking test(10MWT)[MD=-2.00,95%CI(-2.91,-1.08),P<0.0001]was better than that of the control group.Conclusion:The current analysis results show that compared to conventional rehabilitation therapy or continuous aerobic exercise,HIIT has more advantages in improving the cardiopulmonary function of stroke patients.

Clinical Study of Intermittent Levosimendan in the Treatment of Acute Heart Failure

[Objectives] To investigate the clinical efficacy of intermittent levosimendan in the treatment of acute heart failure. [Methods] 100 patients diagnosed with acute heart failure and hospitalized in the internal medicine-cardiovascular department in The First People s Hospital of Yulin from January 2019 to February 2020 were randomly divided into two groups, 50 cases in each group. Both groups were treated with conventional anti-heart failure drugs. The control group was given levosimendan once, and the observation group was given levosimendan three times, with an interval of one month. The creatinine (Cr) level, serum NT proBNP, left ventricular ejection fraction (LVEF) and left ventricular end diastolic diameter (LVEDD) were observed at 48 h before and after treatment and one month and two months after treatment in both groups. [Results] Compared with before treatment, the levels of NT-proBNP decreased in the two groups at 48 h after treatment, and the difference was statistically significant ( P <0.05). The Cr level of the control group did not change significantly before and after treatment, and the Cr level of the observation group decreased at one and two months after treatment compared with before treatment, with statistically significant differences ( P <0.05). Compared with before treatment, NT-proBNP and LVEDD decreased and LVEF increased at one and two months after treatment, and the differences were statistically significant ( P <0.05). There were no obvious adverse reactions in the two groups of patients during the treatment. [Conclusions] Repetitive use of levosimendan in the treatment of acute heart failure could significantly improve the renal function, cardiac contractility and cardiac function of patients, and with the passage of time, the treatment effect was improved, which is worthy of clinical promotion.

Optimization of Intermittent Variable Power Microwave Heating Process for Blueberry Pulp

To improve heating uniformity and anthocyanin content of the blueberry pulp under microwave heating,the intermittent variable power microwave heating technology was introduced in the study.The effects of technology parameters in terms of high microwave intensity heating time,intermittent time,low microwave intensity and low microwave intensity heating time on the blueberry pulp quality parameters(heating uniformity,average moisture content,the highest temperature and anthocyanin content)were investigated by using the response surface method.The results showed that the longer heating time under different microwave intensities resulted in the poorer heating uniformity.The intermittent stage promoted heat and mass transfer within the pulp and reduced the temperature difference and moisture gradient within the pulp,which enhanced desired uniformity of temperature and moisture distribution before entering the low microwave intensity heating stage.Therefore,the longer the intermittent time,the greater the heating uniformity.The optimal parameters were developed as high microwave intensity of 4 W·g^(-1),high microwave intensity heating time of 9.86 min,intermittent time of 10 min,low microwave intensity of 2.2 W·g^(-1)and low microwave intensity heating time of 6 min.This research might provide guidance for microwave heating berry fruits.

Assessment of Physicians’ Knowledge of Clean Intermittent Urinary Self-Catheterization in an African Country: The Case of Senegal

Introduction: Clean intermittent self-catheterization is the gold standard for the management of urinary retention. But its use remains limited in our practice. Objective: We are conducting this study to assess physicians’ knowledge of its practice in order to promote its promotion. Material and Methods: We conducted a cross-sectional, prospective, descriptive and analytical study in two hospitals in Dakar for two months. The resident doctors were interviewed on the basis of a questionnaire developed based on the recommendations of the French Society of Physical Medicine and Rehabilitation (SOFMER). Results: 54 medical residents returned the questionnaire. 63% of physicians surveyed defined the clean intermittent self-catheterization as a sterile intermittent self-catheterization. 70.9% of the doctors surveyed had cited urinary retention as an indication for the clean intermittent self-catheterization;53.7% advocated sterile gloves for the catheterization;29.6% proposed a frequency of one to two times and 2 to 4 catheterizations per day. 70.4% of doctors recommended indicating Cytobacteriological examination of urine in case of symptoms of urinary tract infection. Antibiotic therapy from the outset was offered by 83.3% of doctors in case of symptoms of urinary tract infection under intermittent self-sounding. 59.3% were unaware of clean intermittent self-catheterization. Discussion and Conclusion: Apart from the indica-tions, the clean intermittent self-catheterization remains unknown by res-ident doctors and its practice remains to be mastered, hence the need to establish a course on its practice at the faculty of medicine.

A New Device for Intermittent Emptying of the Bladder in Children and Adults: A Long-Term Follow-Up

Contextualization: Emptying the bladder is a challenging problem for the urological community. Intermittent catheterization is the most widely used method to restore bladder emptying mechanism. However, this procedure can have a negative impact on self-image and result in a decline in the quality of life of patients. In this context, the use of a bladder emptying device (SVCATH3D) proposes to be effective and have a positive impact on the quality of life of different patients. Objective: The objective of the study was to evaluate the functionality of a new device for both intermittent and controlled emptying of the bladder in both sexes and ages. Materials and methods: A randomized clinical trial was conducted with 251 patients, with different bladder problems, from March 2013 to January 2023. After randomization, the patients were divided into two groups: Group I (SVCATH3D) and Group II (Clean Intermittent Catheterization). The primary outcome was defined as the impact on quality of life. Data on episodes of urinary tract infection, adverse effects, number of diaper use and treatment costs were analyzed. Results: The apposition of the SVCATH3D was performed on an outpatient basis, with no complications during the procedures. The patients were followed up for 10 years. There was a significant improvement in quality of life when comparing the moments before and after the use of SVCATH3D (p Conclusion: The study using SVCATH3D showed promising results in relation to functionality, showing improvement in quality of life with a reduction in episodes of urinary infection and amount of diapers/day. This allows us to conclude that SVCATH3D can represent an important step in the treatment of patients suffering from various bladder problems both incontinence and affecting emptying mechanism.

Advances in intermittent fasting and neurodegeneration

Intermittent fasting is a kind of diet that extends the fasting time every day or several days per week.It mainly includes time-limited eating,alternate day fasting and periodic fasting.Intermittent fasting triggers evolutionary indications and conserved cellular responses to protect and improve body status by triggering a"metabolic switch"from hepatogenic glucose to adipocyte-derived ketone bodies.Gut microbiota and circadian rhythms have also been linked to intermittent fasting.This article focuses on the research progress of intermittent fasting and neurodegenerative diseases in order to provide a theoretical basis for nutritional treatment of neurodegenerative diseases.

Relationship among intermittent pulse,regularly intermittent pulse,and bradyarrhythmia

Pulse diagnosis is an important basis for the diagnosis of Chinese medicine.It is the rich experience accumulated by the predecessors in the long and continuous practice,and it is a unique diagnosis method of Chinese medicine.There are many names of pulse conditions in traditional Chinese medicine.The four elements are analyzed and summarized in terms of position,number,shape,and momentum.The four elements are used as 28 kinds of pulses.Among them,the regularly intermittent pulse and the intermittent pulse are characterized by arrhythmia and intermittent stop of the pulse.Intermittent pulse means irregular intervals;when a pulse comes,Regularly Intermittent pulse have regular stops.This kind of phenomenon is similar to the bradyarrhythmia in modern medicine.The knot pulse is an irregular pulse stopping,which can be seen clinically in sinus arrest,second-degree type I sinus block,second-degree type I atrioventricular block,and escape beats and so on.On the other hand,Regularly Intermittent pulse is a regular pulse stopping,which can be clinically found in the second degree type II sinus block,the second degree type II sinus block,and the second degree type I atrioventricular block with a special 2:1 type of atrioventricular block type and so on.

Clearance Influence on Dynamic Response of Intermittent Roller Chain Drive

The clearances appear in chain link hinges induced by manufacturing tolerance or wear of components are the most important factor that influences the dynamic performance of the intermittent roller chain drives. Due to the existence of the clearances in chain link hinges, the serious impact vibration phenomenon which influences the stability and the position accuracy of the chain drive system would be caused in the intermittent motion. But, the problem may be that a reasonable modeling on the chain with clearances is difficult due to the large clearance＇s number in chain system and the fact that the clearance＇ size are different. Currently, the studies on the dynamics of the intermittent roller chain considering the multi-clearance＇ joints are rare. Most research works have only focused on the constant moving chains. Taking the intermittent roller chain system as an object, this paper designs and builds the experimental device of this kind of mechanical system. The Longitudinal vibration response of the intermittent chain under the different motion laws was tested. The experimental study shows that the clearances presented in chain link hinges can cause severe impact vibration in the intermittent motion of chain. In subsequent work, the dynamic model of the intermittent roller chain system with the multi-clearance＇ joints was established. By calculating the dynamic response of this kind of mechanical system under the different motion laws, the effect of the clearances on the dynamic response of the intermittent chain drive system was analyzed. The theoretical simulation shows that the serious impact vibration phenomenon of the chain system can be caused by the clearances at the start accelerating period, and the chain drive system is often accompanied by the severe shock and vibration at the moment that the chain moves from the acceleration period to deceleration period. The research conclusions made by the experimental and theoretical studies indicate that the use of motion laws with small and continuous jerk at conversion point can effectively suppress the impact vibration at this point caused by clearances＇ effect. Additionally, the use of nonsymmetrical motion laws with small jerk approaching the end of the indexing period can obtain a smaller residual vibration. The presented motion law can provide an important reference for the improvement of the dynamic performance of the intermittent chain drive systems.

Safe upper limit of intermittent hepatic inflow occlusion for liver resection in cirrhotic rats

AIM To evaluate the effects of varying ischemic durations on cirrhotic liver and to determine the safe upper limit of repeated intermittent hepatic inflow occlusion.``METHODS Hepatic ischemia in cirrhotic rats was induced by clamping the common pedicle of left and median lobes after non-ischemic lobes resection. The cirrhotic rats were divided into six groups according to the duration and form of vascular clamping: sham occlusion (SO),intermittent occlusion for 10 (IO-10), 15(IO-15). 20(IO-20)and 30(IO-30) minutes with 5 minutes of refiow andcontinuous occlusion for 60 minutes (CO-60). All animals received a total duration of 60 minutes of hepatic inflow occlusion. Liver viability was investigated in relation of hepatic adenylate energy charge ( EC ).Triphenyltetrazollum chloride (TTC) reduction activities were assayed to qualitatively evaluate the degree of irreversible hepatocellular injury. The biochemical and morphological changes were also assessed and a 7-day mortality was observed.``RESULTS At 60 minutes after reperfusion following atotal of 60 minutes of hepatic inflow occlusion, EC values in lO-L0 (0.749±:0.012) and IO-15 (0.699 ±0.002) groups were rapidly restored to that in SO group (0. 748± 0.016).TTC reduction activities remained in high levels (0. 144 ±0.002 mg/mg protein, 0. 139 + 0.003 mg/mg protein and 0.121 ± 0.003 mg/mg protein in SO, IO-10 and IO-15groups, respectively). But in IO-20 and IO-30 groups, EC levels were partly restored (0.457 ± 0.023 and 0.534 ±0.027) accompanying with a significantly decreased TTCreduction activities (0.070 ± 0.005 mg/mg protein and 0.061 ±0.003 rng/mg protein). No recovery in EC values , i).228 ± 0.004) and a progressive decrease in TTC reduction activities ( 0.03.3 ± 0.002 mg/mg protein) were shown in CO-60 group. Although not significantly different, the activities of the serum aspartate aminotransferase (AST) on the third postoperative day (POD3 ) and POD7 and of the serum alanineaminotransferase (ALT) on POD3 in CO-60 group remained higher than that in intermittent occlusion groups.Moreover, a 60% animal mortality rate and more severe morphological alterations were also shown in CO-60group.``CONCLUSION Hepatic inflow occlusion during 60 minutes for liver resection in cirrhotic rats resulted in less hepatocellular injury when occlusion was intermittent rather than continuous. Each period of 15 minutes was the safe upper limit of repeated intermittent vascular occlusion that the cirrhotic liver could tolerate without undergoing irreversible hepatocellular injury.

Expression of RUNX2 and MDM21 in rats with periodontitis under chronic intermittent hypoxia

Objective: To discuss the expression of RUNX2 and MDM21 in rats with periodontitis under the chronic intermittent hypoxia. Methods: A total of 32 SD healthy rats were randomly divided into four groups, with 8 rats in each group. The molecular biological techniques of immunohistochemistry, RT-PCR and Western blotting were employed to detect the effect of different hypoxia time(0, 6, 12, 24 and 48 h) and different concentrations of hypoxia(0.000, 0.001, 0.010, 0.060 and 0.100 ppm) on the expression of RUNX2 and MDM21 in rats of four groups. Results: The expression of RUNX2 and MDM21 in each group was significantly higher than the one at other concentrations when the concentration was 0.010 ppm, with the statistical difference(P<0.05). The expression of RUNX2 and MDM21 was that normoxic control group > periodontitis group> chronic intermittent hypoxia group > compound group under the action with the concentration of 0.010 ppm for 12 h, but there was no significant difference for the comparison among groups(P>0.05). Conclusions: The condition of chronic intermittent hypoxia can reduce the expression of RUNX2 and MDM21 in rats with periodontitis and aggravate the damage of periodontal bone.