The association between gray matter volume in the hippocampal subfield and antidepressant efficacy mediated by abnormal dynamic functional connectivity

An abnormality of structures and functions in the hippocampus may have a key role in the pathophysiology of major depressive disorder (MDD). However, it is unclear whether structure factors of the hippocampus effectively impact antidepressant responses by hippocampal functional activity in MDD patients. We collected longitudinal data from 36 MDD patients before and after a 3-month course of antidepressant pharmacotherapy. Additionally, we obtained baseline data from 43 healthy controls matched for sex and age. Using resting-state functional magnetic resonance imaging (rs-fMRI), we estimated the dynamic functional connectivity (dFC) of the hippocampal subregions using a sliding-window method. The gray matter volume was calculated using voxel-based morphometry (VBM). The results indicated that patients with MDD exhibited significantly lower dFC of the left rostral hippocampus (rHipp.L) with the right precentral gyrus, left superior temporal gyrus and left postcentral gyrus compared to healthy controls at baseline. In MDD patients, the dFC of the rHipp.L with right precentral gyrus at baseline was correlated with both the rHipp.L volume and HAMD remission rate, and also mediated the effects of the rHipp.L volume on antidepressant performance. Our findings suggested that the interaction between hippocampal structure and functional activity might affect antidepressant performance, which provided a novel insight into the hippocampus-related neurobiological mechanism of MDD.

Linking inter-subject variability of cerebellar functional connectome to clinical symptoms in major depressive disorder

Major depressive disorder (MDD) is a highly prevalent psychiatric disorder with remarkable inter-subject variability in clinical manifestations. Neuroimaging changes of the cerebellum have been recently proposed as a way to characterize MDD-related brain disruptions and might further explain various clinical symptoms. However, the cerebellar contributions to MDD clinical heterogeneity remain largely unknown. The analyzed data consisted of 251 MDD patients and 235 matching healthy controls (HC). The inter-subject variability of functional connectomes (IVFC) was estimated via Pearson's correlation analysis between each pair of the cerebellar and cerebral regions based on resting-state functional magnetic resonance imaging (rs-fMRI). A partial least squares (PLS) regression analysis was performed to determine the potential dimension linking the IVFC to clinical symptom measures. The results indicated that similar spatial distribution patterns of the cerebellar IVFC were observed between MDD and HC, but the MDD group exhibited abnormal IVFC alterations in the bilateral Cerebelum_4_5, bilateral Cerebelum_6, Vermis_1_2 and Vermis_8. The PLS model revealed that the IVFC pattern in the left Cerebelum_6 was significantly associated with three HAMD-17 items including the work and activities, psychomotor retardation, and depressed mood. These findings provided new evidence for the cerebellar changes in MDD. Specifically, we found that the altered inter-subject variability measurements correlated with clinical manifestations of this illness. Elucidating this variability could prove helpful for the evaluation of MDD heterogeneity as well as for understanding its pathophysiological mechanism.

[Opportunities and challenges in an emerging interdisciplinary research field-cardio-oncology]

The field of oncology has made remarkable progress over the past two decades. With the aging of the population, the number of cancer survivors is increasing. At the same time, cancer therapy-related cardiovascular toxicity (CTR-CVT) has become an important cause that seriously affects the quality of life and survival of cancer patients. In this context, cardio-oncology, an emerging interdisciplinary field, emerged. The types and treatment strategies of oncological diseases are heterogeneous, and the management of cancer patients also requires the participation of multiple disciplines. Currently, there are still insufficient clinical research and evidence-based practice in the field of cardio-oncology, resulting in a lack of standardization in its diagnosis and treatment. Additionally, the training model of physicians in cardio-oncology is still being explored. This article provides a comprehensive exploration of the opportunities and challenges faced by physicians and researchers in the field of cardio-oncology. It also delves into the prevailing landscape of clinical research in China and outlines the future training model for physicians in cardio-oncology.

Circadian nuclear receptor Rev-erbalpha is expressed by platelets and potentiates platelet activation and thrombus formation

Background

Adverse cardiovascular events have day/night patterns with peaks in the morning, potentially related to endogenous circadian clock control of platelet activation. Circadian nuclear receptor Rev-erbα is an essential and negative component of the circadian clock.

Purpose

We aim to investigate the expression profile and biological function of Rev-erbα in platelets.

Methods and results

Here we report the presence and functions of circadian nuclear receptor Rev-erbα in human and mouse platelets. Both human and mouse platelet Rev-erbα showed a circadian rhythm that positively correlated with platelet aggregation. Global Rev-erbα knockout and platelet-specific Rev-erbα knockout mice exhibited defective in hemostasis as assessed by prolonged tail-bleeding times. Rev-erbα deletion also reduced ferric chloride-induced carotid arterial occlusive thrombosis, prevented collagen/epinephrine-induced pulmonary thromboembolism, and protected against microvascular microthrombi obstruction and infarct expansion in an acute myocardial infarction model. In vitro thrombus formation assessed by CD41-labeled platelet fluorescence intensity was significantly reduced in Rev-erbα knockout mouse blood. Platelets from Rev-erbα knockout mice exhibited impaired agonist-induced aggregation responses, integrin αIIbβ3 activation and α-granule release. Consistently, pharmacological inhibition of Rev-erbα by specific antagonists decreased platelet activation markers in both mouse and human platelets. Mechanistically, mass spectrometry and co-immunoprecipitation analyses revealed that Rev-erbα potentiated platelet activation via oligophrenin-1-mediated RhoA/ERM (ezrin/radixin/moesin) pathway.

Conclusion

We provide the first evidence that circadian protein Rev-erbα is functionally expressed in platelets and potentiates platelet activation and thrombus formation. Rev-erbα may serve as a novel therapeutic target for managing thrombosis-based cardiovascular disease.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): This work was supported by grants from the National Science Fund for Distinguished Young Scholars (81625002), the National Natural Science Foundation of China (81930007).

Circadian disruption on the susceptibility to sepsis-induced cardiac dysfunction: a prospective multi-modal imaging study

Background

Sepsis is a significant cause of mortality, and cardiac dysfunction is one of the vital predictors for mortality of sepsis. However, the factors associated with the susceptibility to sepsis-induced cardiac dysfunction remain unclear. Disruption of circadian rhythms can profoundly influence cardiac health; however, to the knowledge of the authors, the relationship of circadian disruption to cardiac involvement in patients with sepsis is unknown.

Purpose

We aim to investigate the impact of circadian disruption on the susceptibility to sepsis-induced cardiac dysfunction.

Methods

Study patient data were obtained from the image database of EARLY-MYO-SEPSIS (EARLY assessment of MYOcardial tissue characteristics by multi-modal imaging in SEPSIS) registry, which was a prospective, multi-center registry of sepsis patients who have undergone cardiac magnetic resonance imaging (MRI) and echocardiography from 8 sites (clinical trial number NCT04513795). Cardiac involvement was evaluated using a comprehensive assessment comprising of echocardiography (with global longitudinal strain calculation), cardiac MRI and cardiac biomarker evaluation. Logistic regression was performed to identify independent predictors of left ventricular systolic dysfunction in sepsis.

Results

A total of 216 intensive care unit patients with sepsis was enrolled in the present analysis. Septic patients with a history of circadian disruption (i.e., sleep insufficiency <6 hours) presented more cardiac involvements (as indicated by edema on the cardiac MRI along with cardiac deformation and increased cardiac biomarkers) compared with those without circadian disruption history. Moreover, septic patients with a history of circadian disruption had increased mortality and incidence of heart failure. A history of circadian disruption was identified as an independent predictor of left ventricular systolic dysfunction in sepsis.

Conclusions

Our data from EARLY-MYO-SEPSIS registry demonstrated a previously unappreciated circadian sensitivity to sepsis-induced cardiac dysfunction.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work was supported by grants from the National Science Fund for Distinguished Young Scholars (81625002) and National Natural Science Foundation of China (81930007)

[Perinatal outcomes on mortality and influencing factors among HIV-infected mothers in Sichuan province]

Objective: To explore the influencing factors on perinatal mortality of pregnant women with HIV infection to reduce the mother-to-child transmission in Sichuan province. Methods: In this study, 4 786 perinatal infants of the HIV-infected pregnant women were included. Related data on perinatal epidemiology was reported by all the 183 medical and health care institutions where the HIV prevention of mother-to-child transmission program was initiated in 2005-2016. Univariate χ(2) test and multivariate logistic regression methods were used to analyze the perinatal mortality outcomes and influencing factors. Results: The overall perinatal mortality rate was 25.7‰ (123/4 786) among HIV-infected pregnant women, with annual downwarding trend (trend χ(2)=32.220, P=0.000). Perinatal mortality rate appeared the highest (χ(2)=4.130, P=0.042), with more fetal deaths and stillbirths and less early neonatal death within 7 days in Liangshan county (χ(2)=29.626, P=0.000). Results from the multivariate logistic regression analysis showed that fewer pregnant numbers would contribute to the, lower perinatal mortality rate (1-2 pregnancies OR=0.417, 95%CI: 0.184-0.943; 3-4 pregnancies OR=0.447, 95%CI: 0.223-0.895). Perinatal deaths were more likely to be prevented if LPV/r protease inhibitor-based triple antiviral therapy was provided (OR=0.530, 95%CI: 0.285- 0.986) or delivery was taken place in the hospital (hospital of municipal-level and above OR=0.222, 95%CI:0.098-0.499; county-level hospital OR=0.282, 95%CI: 0.166-0.480; township-level hospital OR=0.134, 95%CI: 0.031-0.586) among HIV-infected pregnant women. However, premature delivery or neonatal asphyxia would increase the risk of perinatal mortality (premature delivery OR=8.285, 95%CI: 5.073-13.533; neonatal asphyxia OR=9.624, 95%CI: 4.625-20.028). Conclusions: The perinatal mortality rate of HIV-infected pregnant women appeared significantly higher than that in the province or the whole country. Strategies involving LPV/r-based triple antiviral therapy, promotion of hospital delivery, reducing the incidence rates of premature deliveries and neonatal asphyxia, should be strengthened.

[HIV positive rate from different detection methods in medical institutions in China: a Meta analysis]

Objective: To analyze the HIV positive detection rate from different detection channels in Chinese medical institutions. Methods: A Meta-analysis was conducted. First of all, the literature on HIV testing of medical institutions in China was systematically searched on China National Knowledge Infrastructure, Wanfang Data Knowledge Service Platform, VIP Information Chinese journal Service platform and PubMed. Secondly, a self-made information table was used to collect the basic information, HIV positive number and test number of the literature. Finally, R 4.0.2 software was used to calculate the pooled HIV detection rate and 95%CI of the whole population, detection approaches subgroups and regions subgroups, and then the forest map was drawn. Funnel plot was used to analyze publication bias. Results: A total of 45 studies which covered 22 provinces. Meta analysis showed that the pooled HIV positive rate was 0.82‰ (95%CI: 0.62‰-1.04‰). Subgroup analysis showed that the HIV positive rate of STD outpatient was the highest (3.01‰ (95%CI: 1.76‰-4.58‰), followed by other patients (1.43‰ (95%CI: 1.00‰-1.93‰)). The HIV positive rate of western China was the highest (1.14‰ (95%CI: 0.72‰-1.63‰)). The HIV positive rate in 2008-2017 was higher than in 2000-2007. The Egger test indicated no publication bias (t=-0.737, P=0.465). Conclusion: The HIV positive detection rate of patients in medical institutions in China was at a low level, but the positive rate of patients in STD clinics was relatively high. Therefore, the HIV testing should be further expanded in this population. Secondly, HIV screening should be strengthened for other patients.

Comparison of trans-catheter closure of paravalvular leak versus surgical approach-outcomes and cost analysis

Background

The outcomes and costs of trans-catheter closure (TC) of paravalvular leak (PVL) compared with surgical closure (SC) are rarely described.

Purpose

The aim of the study was to assess the outcomes and hospital costs of patients who underwent TC or SC of PVL in our center.

Methods

Patients who underwent TC and SC of PVL between Jan. 2016 and Dec. 2019 were enrolled. Baseline characteristics, procedural, in-hospital and mid-term outcomes and hospital costs were compared.

Results

A total of 141 patients were studied (TC, n=65 and SC, n=76). The patients were elder in TC group (56.8±12.8 years vs. 50.1±12.8 years, p=0.002). Technical success was higher in SC group (83.1% vs. 98.7%, p<0.001). Procedure room time (93±38 min vs. 395±132 min, p<0.001), intensive care unit time (0 h vs. 25 h, p<0.001), length of stay from hospitalization to discharge (7 days vs. 21 days, p<0.001) and costs (¥45090±19343 vs. ¥164165±94300, p<0.001) were significantly less in TC group. After risk adjustment, there was no significant differences between in 30 days survival between TC group and SC group. However, the residual PVLs were less in SC group (43.1% vs. 12.0%, p=0.012). At a median follow-up of 21 months, there was a trend towards reduce all-cause death following TC versus SC (OR=0.054, 95% CI: 0.070 to 0.445, p=0.007).

Conclusions

SC for PVL is associated with higher technical rates and less residual shunt. But, the shorter length of stay and lower resources use with TC group significantly reduce hospital costs. In addition, TC achieve a better mid-term results in survival.

Funding Acknowledgement

Type of funding source: None

Global longitudinal diastolic strain rate as a novel marker for predicting adverse outcomes in hypertrophic cardiomyopathy by cardiac magnetic resonance tissue tracking

AIM

To examine the prognostic value of global peak diastolic strain rate (PDSR) derived from cardiac magnetic resonance (CMR) tissue tracking (CMR-TT) in predicting adverse outcomes in hypertrophic cardiomyopathy (HCM) patients.

MATERIALS AND METHODS

A total of 98 patients diagnosed with HCM (44 patients had left ventricle [LV] outflow tract obstruction [LVOTO] and 54 patients did not) were enrolled and followed for the specified endpoint. LV global myocardial mechanics was assessed in all participants using CMR-TT at study entry.

RESULTS

Compared with the non-obstructive subgroup, the obstructive subgroup demonstrated deteriorated magnitude of LV global radial, circumferential, and longitudinal PDSR (all p<0.05). After a mean follow-up period of 4.5 years, 24 patients reached an endpoint before the end of the study. Furthermore, when using the specified cut-off value (0.33 1/s) of longitudinal PDSR, the Kaplan-Meier curve demonstrated that patients with lower longitudinal PDSR had a significantly lower freedom from major adverse cardiovascular events (MACE) compared with their counterparts in the non-obstructive, obstructive, and overall cohorts (all log-rank p<0.05). Multivariable analysis showed that longitudinal PDSR remained the strongest predictor of outcome after adjusting for baseline and CMR variables (hazard ratio, 2.65; 95% confidence interval, 2.21-11.44; p<0.05).

CONCLUSION

CMR-TT-derived longitudinal PDSR is probably considered a novel and easy-to-perform marker for predicting adverse outcomes in HCM patients, which is beneficial to risk stratification. Further confirmatory studies are needed.

[A multicenter randomized prospective study of concurrent chemoradiation with 60 Gy versus 50 Gy for inoperable esophageal squamous cell carcinoma]

Objective: To determine whether 60 Gy is superior to standard 50 Gy for definitive concurrent chemoradiation(CCRT) in esophageal squamous cell carcinoma (ESCC) using modern radiation technology in a phase Ⅲ prospective randomized trial. Methods: From April 2013 to May 2017, 331 patients from 22 hospitals who were pathologically confirmed with stage ⅢA-ⅣA ESCC were randomized to 60 Gy or 50 Gy with random number table. Total of 305 patients were analyzed, including 152 in 60 Gy group and 153 in 50 Gy group. The median age was 63 years, 242(79.3%) males and 63(20.7%) females. The median length of primary tumor was 5.6 cm. The clinical characteristics between two groups were comparable. All patients were delivered 2 Gy per fraction, 5 fractions per week. Concurrent weekly chemotherapy with docetaxel (25 mg/m(2)) and cisplatin (25 mg/m(2)) and 2 cycles consolidation chemotherapy with docetaxel (70 mg/m(2)) and cisplatin (25 mg/m(2), d1-3) were administrated. The primary endpoint was local/regional progression-free survival (LRPFS). The data were compared with Pearson chi-square test or Fisher's exact test. Results: At a median follow-up of 27.3 months, the disease progression rate was 37.5% (57/152), 43.8% (67/153) in the high and standard-dose group, respectively (χ(2)=1.251, P=0.263). The 1, 2, 3-year LRPFS rate was 75.4%, 56.8%, 52.1% and 74.2%, 58.4%, 50.1%, respectively (HR: 0.95, 95%CI: 0.69-1.31, P=0.761). The 1, 2, 3-year overall survival rate was 84.1%, 64.8%, 54.1% and 85.4%, 62.9%, 54.0%, respectively (HR: 0.98, 95%CI: 0.71-1.38, P=0.927). The 1, 2, 3-year progression-free survival rate was 70.8%, 54.2%, 48.5% and 65.5%, 51.9%, 45.1%, respectively (HR: 0.93, 95%CI: 0.68-1.26, P=0.621). The incidence rates in toxicities between the two groups were similar except for higher rate of severe pneumonitis in high dose group (χ(2)=11.596, P=0.021). Conclusions: The efficacy in disease control is similar between 60 Gy and 50 Gy using modern radiation technology concurrent with chemotherapy for ESCC. The 50 Gy should be recommended as the regular radiation dose with CCRT for ESCC.

The relationship between regulatory T cells and radiation therapy

Radiation therapy (RT) is an effective treatment for cancer. Approximately, 70% of cancer patients receive RT in China. The immune-modulating effect of radiation therapy have gained considerable interest in recent years and there have been multiple reports of synergy between radiation and immunotherapy. Regulatory T cells (Tregs) are a group of T cell subsets with immunosuppressive function, which is correlated with cancer. Tregs are involved in the pathogenesis, development, treatment and prognosis of tumors by cell-cell contact, cytokines, and cell metabolism. Based on the immunological characteristics of Tregs, this article reviews the interaction between RT and immune molecules, aiming to provide new ideas for RT combined with immunotherapy.

Correlation between gene polymorphism and opioid efficacy in patients with gastric or intestinal cancer

OBJECTIVE

To explore the correlation between gene polymorphism and opioid efficacy in patients with gastric or intestinal cancer.

PATIENTS AND METHODS

Fifty-nine patients who underwent laparoscopic surgery for gastric or intestinal cancer under general anesthesia were included and randomly divided into oxycodone (n=30) and sufentanil groups (n=29) by reproducible random number generation method. Single nucleotide polymorphisms (SNPs) of four alleles: μ-opioid receptor gene OPRM1 A118G, cytochrome P450 (CPY450) enzyme system: CPY3A4*1G, CYP3A5*3, and CYP2D6*10 were detected by PCR-pyrosequencing. Patients in sufentanil group received intravenous sufentanil injection during anesthesia induction, intraoperative maintenance, and postoperative analgesia, while those in oxycodone group received oxycodone. Patients' postoperative VAS score, opioid use, and prevalence of adverse reactions were recorded.

RESULTS

The genotype distribution of OPRM1 A118G, CYP3A4*1G, CYP3A5*3, and CYP2D6*10 in Chinese gastric cancer/intestinal cancer patients accorded with the Hardy-Weinberg law (p>0.05). OPRM1 A118G polymorphism correlated with postoperative VAS score and medication dosage, in oxycodone group (p<0.05), while it didn't with those of sufentanil group. The VAS scores in GG group were higher than that in AA group and AG group at T6-T9, (p<0.05); the postoperative pain remedies times in GG group were more than that in the AA and AG groups (p=0.002). CYP3A4*1G polymorphism related to postoperative VAS score, medication dosage and prevalence of adverse reactions in sufentanil group (p<0.05), while it didn't with those of oxycodone group (p>0.05). The total intraoperative medication in AA group was less than that in GG and GA groups (p<0.01), with a higher prevalence of respiratory depression (p=0.01). Nor was there any correlation of CYP3A5*3 and CYP2D6*10 polymorphisms with the efficacy, postoperative VAS score, pain remedies times, postoperative 24 h medication dosage, or prevalence of adverse reactions in oxycodone and sufentanil groups.

CONCLUSIONS

Gene polymorphism affects the efficacy and adverse reactions of opioids in patients undergoing laparoscopic gastric or intestinal cancer surgery.

Effects of dietary energy and lipase levels on nutrient digestibility, digestive physiology and noxious gas emission in weaning pigs

Objective

This study was conducted to evaluate the effect of dietary energy and lipase supplementation on growth performance, nutrient digestibility, serum profiles, intestinal morphology, small intestinal digestive enzyme activities, biochemical index of intestinal development and noxious gas emission in weaning pigs.

Methods

A total of 240 weaning pigs ([Yorkshire×Landrace]×Duroc) with an average body weight (BW) of 7.3±0.12 kg were used in this 28-d experiment. Weaning pigs were randomly allocated to 4 dietary treatments in a 2×2 factorial arrangement with 2 levels of energy (net energy = 2,470 kcal/kg for low energy diet and 2,545 kcal/kg for basal diet) and 2 levels of lipase (0 and 1.5 U/g of lipase) according to BW and sex. There were 6 replications (pens) per treatment and 10 pigs per pen (5 barrows and 5 gilts).

Results

Weaning pigs fed the low energy diet had lower (p<0.05) gain-to-feed ratio (G:F) throughout the experiment, apparent digestibility of dry matter, nitrogen, ether extract, and gross energy during d 0 to 14, average daily gain during d 15 to 28, lipase activity in duodenum and ileum and protein/DNA in jejunum (p<0.05), respectively. Lipase supplementation had no effect on growth performance but affected apparent nutrient digestibility (p<0.05) on d 14 and enhanced lipase activity in the duodenum and ileum and protease activity in duodenum and jejunum of pigs (p<0.05) fed the low energy diet. Lipase reduced serum low-density lipoprotein cholesterol (LDL-C) and triglyceride (TG), NH₃ production (p<0.05) from the feces.

Conclusion

The low energy diet decreased G:F throughout the experiment and nutrient digestibility during d 0 to 14 as well as lipase activity in duodenum and ileum. Lipase supplementation increased nutrient digestibility during d 0 to 14 and exerted beneficial effects on lipase activity in duodenum and ileum as well as protease activity in duodenum and jejunum, while reduced serum LDL-C, TG and fecal NH₃.

Multiple ATP-binding cassette transporters are involved in insecticide resistance in the small brown planthopper, Laodelphax striatellus

ATP-binding cassette (ABC) transporters are membrane-bound proteins involved in the movement of various substrates, including drugs and insecticides, across the lipid membrane. Demonstration of the role of human ABC transporters in multidrug resistance has led to speculation that they might be an important mechanism controlling the fate of insecticides in insects. However, the role of ABC transporters in insects remains largely unknown. The small brown planthopper, Laodelphax striatellus Fallén, has developed resistance to most of the insecticides used for its control. Our goals were to identify the ABC transporters in La. striatellus and to examine their involvement in resistance mechanisms, using related strains resistant to chlorpyrifos, deltamethrin and imidacloprid, compared with the susceptible strain. Based on the transcriptome of La. striatellus, 40 full-length ABC transporters belonging to the ABCA-ABCH subfamilies were identified. Quantitative PCR revealed that over 20% of genes were significantly up-regulated in different resistant strains, and eight genes from the ABCB/C/D/G subfamilies were up-regulated in all three resistant strains, compared with the susceptible strain. Furthermore, synergism studies showed verapamil significantly enhanced insecticide toxicity in various resistant strains but not in the susceptible strain. These results suggest that ABC transporters might be involved in resistance to multiple insecticides in La. striatellus.

Toward Determining ATPase Mechanism in ABC Transporters: Development of the Reaction Path-Force Matching QM/MM Method

Adenosine triphosphate (ATP)-binding cassette (ABC) transporters are ubiquitous ATP-dependent membrane proteins involved in translocations of a wide variety of substrates across cellular membranes. To understand the chemomechanical coupling mechanism as well as functional asymmetry in these systems, a quantitative description of how ABC transporters hydrolyze ATP is needed. Complementary to experimental approaches, computer simulations based on combined quantum mechanical and molecular mechanical (QM/MM) potentials have provided new insights into the catalytic mechanism in ABC transporters. Quantitatively reliable determination of the free energy requirement for enzymatic ATP hydrolysis, however, requires substantial statistical sampling on QM/MM potential. A case study shows that brute force sampling of ab initio QM/MM (AI/MM) potential energy surfaces is computationally impractical for enzyme simulations of ABC transporters. On the other hand, existing semiempirical QM/MM (SE/MM) methods, although affordable for free energy sampling, are unreliable for studying ATP hydrolysis. To close this gap, a multiscale QM/MM approach named reaction path-force matching (RP-FM) has been developed. In RP-FM, specific reaction parameters for a selected SE method are optimized against AI reference data along reaction paths by employing the force matching technique. The feasibility of the method is demonstrated for a proton transfer reaction in the gas phase and in solution. The RP-FM method may offer a general tool for simulating complex enzyme systems such as ABC transporters.

Achievement of linear response for competitive bioaffinity assays of ligands: criteria of optimized interaction systems

For a linear response, an optimized competitive bioaffinity assay of a ligand requiresC_RT> 3 ×C_PT,C_PT> 50 ×K_dR, andK_dR> 260 ×K_dX(C_RTandC_PTare concentrations of the probe and protein whileK_dXandK_dRareK_dfor the ligand and probe, respectively).

¹H-MRS before and after resuscitation following selective cerebral ultra-profound hypothermic blood flow occlusion in monkeys

We investigated the effect of selective cerebral ultra-profound hypothermic blood flow occlusion on brain tissue and cell metabolism to ascertain the efficacy and safety of selective deep hypothermic technologies using proton magnetic resonance spectroscopy ((1)H-MRS). The bilateral carotid artery was blocked at room temperature for 10 min. Other neck vessels were then blocked through cold perfusion of the internal carotid artery and reflux of the ipsilateral jugular vein. Thus, selective cerebral extracorporeal circulation was established. Brain temperature was reduced to 15.1° ± 0.9°C. After 60 min, cerebral blood flow recovered naturally. Routine magnetic resonance imaging (MRI), diffusion-weighted imaging (DWI), and (1)H-MRS examination of the bilateral frontal cortex and basal ganglia were performed prior to surgery and 4, 24, 72 h, 21 days after recovery. The formants and areas under the curve (AUC) of N-acetyl aspartate (NAA), choline (Cho), creatine/phosphocreatine (Cr/Cr2) were analyzed using 1H-MRS. The pre- and postoperative AUC of NAA and Cho at different time points were compared. Conventional MRI and DWI showed no abnormal signal changes in the brain parenchyma or right basal ganglia before and after surgery (P > 0.05). There was no significant difference in the ratio between NAA/(Cr+Cr2) and Cho/(Cr+Cr2) before and after surgery in the bilateral basal ganglia and frontoparietal regions of the cortex (P > 0.05). Quantitative (1)H-MRS showed that selective deep cerebral hypothermia significantly improved the brain's tolerance to ischemia and hypoxia. Our results could provide a better understanding of the efficacy and safety of selective deep hypothermia and blood flow occlusion.

Changes in hippocampal ultrastructure and vimentin expression in rhesus monkeys following selective deep hypothermia and blood occlusion

Previous studies have shown that selective cerebral profound hypothermia combined with antegrade cerebral perfusion can improve resistance to cerebral hypoxia-ischemia in monkeys. The aim of this study was to observe the effect of selective cerebral profound hypothermia on the ultrastructure and vimentin expression in monkey hippocampi after severe cerebral ischemia. Eight healthy adult rhesus monkeys were randomly divided into two groups: profound hypothermia (N = 5) and normothermia (N = 3). Monkeys in the profound hypothermia group underwent bilateral carotid artery and jugular vein occlusion for 10 minutes at room temperature. Ringer's solution at 4°C was then perfused through the right internal carotid artery and out of the right jugular vein, maintaining the brain temperature below 18°C. Sixty minutes later, cerebral blood flow was restored. The normothermia group underwent all procedures with the exception that the Ringer's solution was 37°C during perfusion. All animals in the profound hypothermia group were successfully resuscitated. No significant abnormalities of hippocampal morphology or ultrastructure were observed. In contrast, no monkeys were alive after perfusion in the normothermia group and they had abnormal hippocampal morphology and ultrastructure to different extents. Vimentin expression in the hippocampus was significantly lower in the profound hypothermia group (47.88% ± 1.66) than the normothermia group (79.51% ± 1.00; P < 0.01). We conclude that selective cerebral profound hypothermia following 10-min occlusion of the bilateral common carotid arteries was able to downregulate vimentin expression in the hippocampus and protect it from severe cerebral ischemia.

Facile quantitative comparison of specific activities of fusion-tagged enzyme/mutants in cell lysates via prediction of their maximum adsorption by anti-tag antibody immobilized in microplate wells

Maximum activities of 6His-tagged enzyme/mutants from lysates adsorbed on immobilized anti-tag antibody were predicted as specific activities for comparison.

MicroRNA-145 inhibits the growth, invasion, metastasis and angiogenesis of neuroblastoma cells through targeting hypoxia-inducible factor 2 alpha

Recent evidence shows that hypoxia-inducible factor 2 alpha (HIF-2α) may have critical roles in the growth and progression of neuroblastoma (NB) under non-hypoxic conditions. However, the underlying mechanisms and clinical potentials of normoxic HIF-2α expression in NB still remain largely unknown. In this study, HIF-2α immunostaining was identified in 26/42 NB tissues, which was correlated with clinicopathological features. In subtotal 20 NB cases, microRNA-145 (miR-145) was downregulated and inversely correlated with HIF-2α expression. Bioinformatics analysis revealed a putative miR-145 binding site in the 3'-untranslated region (3'-UTR) of HIF-2α messenger RNA (mRNA). Overexpression or knockdown of miR-145 responsively altered both the mRNA and protein levels of HIF-2α and its downstream genes, cyclin D1, matrix metalloproteinase 14 and vascular endothelial growth factor, in normoxically cultured NB cell lines SH-SY5Y and SK-N-SH. In a luciferase reporter system, miR-145 downregulated the luciferase activity of HIF-2α 3'-UTR, and these effects were abolished by a mutation in the putative miR-145-binding site. Overexpression of miR-145 suppressed the growth, invasion, metastasis and angiogenesis of SH-SY5Y and SK-N-SH cells in vitro and in vivo, while restoration of HIF-2α expression rescued the tumor cells from miR-145-mediated defects in these biological features. Furthermore, anti-miR-145 inhibitor rescued the HIF-2α knockdown-mediated repression on the growth, migration, invasion and angiogenesis of NB cells. These data indicate that miR-145 suppresses HIF-2α expression via the binding site in the 3'-UTR under normoxic conditions, thus inhibiting the aggressiveness and angiogenesis of NB.

BLyS expression and JNK activation may form a feedback loop to promote survival and proliferation of multiple myeloma cells

B-Lymphocyte stimulator (BLyS), a member of tumor necrosis factor superfamily, is a potent co-activator of B cells in vitro, and in vivo induces B cell proliferation and immunoglobulin secretion. Multiple myeloma (MM) is an incurable malignancy of terminally differentiated B cells (plasma cells). Previous studies have well ascertained that BLyS plays an important contributory role in the pathogenesis and propagation of multiple myeloma by virtue of its ability to promote B cell survival, expansion, and differentiation. However, the intracellular signaling of BLyS in human MM cells remains undefined. This study was designed to see whether there was interaction between MAPK signaling pathway and BLyS expression. It was found that the active protein p-JNK was expressed in KM3, U266 and PBMCs of MM patients, and that the expression of BLyS could be changed by JNK pathway activator and inhibitor. In addition, recombinant BLyS activated JNK pathway, while BLyS siRNA treatment inhibited the activation of JNK pathway. The level of BLyS expression and the activation of JNK pathway were positively correlated. These findings suggest that JNK activation and BLyS expression in MM cells may form a positive feedback loop that promotes the survival and proliferation of MM cells, and these may shed some light on the pathogenesis and treatment of MM.

Lymphatic sparing versus lymphatic non-sparing laparoscopic varicocelectomy in children and adolescents: a systematic review and meta-analysis

OBJECTIVE

The aim of this study was to explore the true efficacy and potential advantages of lymphatic sparing laparoscopic varicocelectomy (LSV) over lymphatic non-sparing laparoscopic varicocelectomy (LNSV) in children and adolescents.

METHODS

A search was made for studies published up until 31 August 2010 using the terms "lymphatic sparing varicocelectomy", "laparoscopy", "adolescent" and "children" in the Medline, Embase, Ovid, Web of Science, and Cochrane databases. Randomized controlled trials (RCTs) and observational clinical studies (OCSs) comparing LSV and LNSV were included. A systematic review and meta-analysis was performed using odds ratios (ORs) for dichotomous variables.

RESULTS

Out of 127 studies, 2 RCTs and 4 OCSs were eligible for inclusion, comprising 489 cases of LSV and 307 cases of LNSV. The hydrocele rates after LSV were significantly lower than after LNSV (OR = 0.19; 95% confidence interval [CI] = 0.10 to 0.36; p < 0.00001). However, no significant difference was observed between LSV and LNSV with regard to recurrence (OR = 0.65; 95% CI = 0.32-1.33; p = 0.24) or catch-up growth (OR = 2.14; 95% CI =0.97-4.72; p = 0.06).

CONCLUSION

LSV is valuable in reducing the incidence of postoperative hydrocele, with similar recurrence and catch-up growth rates as LNSV. A series of RCTs are warranted to explore the efficacy of LSV in the management of varicocele in children and adolescents.

Association of nuclear factor κB expression with a poor outcome in nasopharyngeal carcinoma

The aim of this study was to determine the relationship between nuclear factor κB and the prognosis of patients with nasopharyngeal carcinoma. We used immunohistochemical studies to examine nuclear factor κB expression in 42 patients with nasopharyngeal carcinoma. The results showed that tumors positive for nuclear factor κB were associated with an increased relapse potential, poor disease-free survival, and reduced overall survival in nasopharyngeal carcinoma. Our study indicates that nuclear factor κB could be an independent molecular marker for predicting poor prognosis among patients with nasopharyngeal carcinoma. Understanding the biology of nuclear factor κB-mediated pathways may lead to the development of novel therapeutic strategies for nasopharyngeal carcinoma.