Effect of exercise duration on toluene-induced locomotor sensitization in mice: a focus on the Renin Angiotensin System.

RATIONALE: Exercise attenuates addictive behavior; however, little is known about the contribution of exercise duration to this positive effect. The Renin Angiotensin System (RAS) has been implicated both in addictive responses and in the beneficial effects of exercise; though, its role in the advantageous effects of exercise on toluene-induced addictive responses has not been explored. OBJECTIVES: To evaluate the impact of different exercise regimens in mitigating the expression of toluene-induced locomotor sensitization and to analyze changes in RAS elements' expression at the mesocorticolimbic system after repeated toluene exposure and following voluntary wheel running in toluene-sensitized animals. METHODS: Toluene-induced addictive-like response was evaluated with a locomotor sensitization model in mice. Toluene-sensitized animals had access to running wheels 1, 2, 4 or 24 h/day for 4 weeks; thereafter, locomotor sensitization expression was evaluated after a toluene challenge. RAS elements (ACE and ACE2 enzymes; AT1, AT2 and Mas receptors) expression was determined by Western blot in the VTA, NAc and PFCx of toluene-sensitized mice with and without exercise. RESULTS: Individual differences in toluene-induced locomotor sensitization development were observed. Access to wheel running 1 and 2 h/day reduced but 4 and 24 h/day completely blocked locomotor sensitization expression. Repeated toluene exposure changed RAS elements' expression in the VTA, NAc and PFCx, while exercise mainly modified ACE and AT1 in air-exposed and toluene-sensitized mice. CONCLUSIONS: Inhalant-exposed animals show different sensitization phenotypes. Exercise duration determined its efficacy to attenuate the addictive-like response. Toluene exposure and exercise each modified RAS, the latter also modifying toluene-induced changes.

Longitudinal Assessment of Quality of Life in Nasopharyngeal Cancer Patients Treated with Intensity-Modulated Proton Therapy and Volumetric Modulated Arc Therapy at Different Time Points.

PURPOSE: This retrospective cohort study aims to compare the quality of life (QoL) in patients with nasopharyngeal cancer (NPC) treated with intensity-modulated proton therapy (IMPT) versus volumetric modulated arc therapy (VMAT) at different time points. MATERIALS AND METHODS: We conducted a longitudinal assessment of QoL on 287 newly diagnosed NPC patients (IMPT: 41 and VMAT: 246). We collected outcomes of global QoL, functional QoL, C30 symptoms, and HN35 symptoms from EORTC QLQ-C30 and QLQ-HN35 questionnaires at pre-radiotherapy, during radiotherapy (around 40 Gy), 3 months post radiotherapy, and 12-months post radiotherapy (RT). The generalized estimating equation was utilized to interpret the group effect, originating from inherent group differences; time effect, attributed to RT effects over time; and interaction of the group and time effect. RESULTS: IMPT demonstrated superior mean dose reductions in 12 of the 16 organs at risk compared to VMAT, including a significant (>50%) reduction in the oral cavity and larynx. Both groups exhibited improved scores of global QoL, functional QoL, and C30 symptoms at 12 months post RT compared to the pre-RT status. Regarding global QoL and C30 symptoms, there was no interaction effect of group over time. In contrast, significant interaction effects were observed on functional QoL (p = 0.040) and HN35 symptoms (p = 0.004) during RT, where IMPT created an average of 7.5 points higher functional QoL and 10.7 points lower HN35 symptoms than VMAT. CONCLUSIONS: Compared to VMAT, dose reduction attributed to IMPT could translate into better functional QoL and HN35 symptoms, but the effect is time dependent and exclusively observed during the RT phase.

Dose- and Time-Dependent Effect of Dietary Blueberries on Diabetic Vasculature Is Correlated with Gut Microbial Signature.

Evidence from our lab and others indicates the vascular effects of dietary blueberries. In the present study, we determined dietary blueberries' dose- and time-dependent effects on diabetic vasculature and their association with gut microbes. Seven-week-old db/db diabetic male mice were fed a diet supplemented with ± freeze-dried wild blueberry powder (FD-BB) for 4, 8, or 12 weeks (three cohorts). Diets contained 0%, 1.23%, 2.46%, and 3.7% of FD-BB, equivalent to 0, ½, 1, and 1.5 human servings of wild blueberries, respectively. The non-diabetic db/+ mice fed a standard diet served as controls. Metabolic parameters, vascular inflammation, and gut microbiome were assessed. Dietary supplementation of 3.7% FD-BB improved vascular inflammation in diabetic mice without improving systemic milieu in all three cohorts. Blueberries improved diabetes-induced gut dysbiosis depending on blueberry dosage and treatment duration. Spearman's correlation indicated that the opportunistic microbes and commensal microbes were positively and negatively associated with indices of vascular inflammation, respectively. Dietary blueberries reduced the opportunistic microbe that was positively associated with vascular inflammation (Desulfovibrio), and increased the commensal microbe that was negatively associated with vascular inflammation (Akkermansia). Dietary blueberries could be a potential adjunct strategy to beneficially modulate gut microbes and improve vascular complications in diabetes.

Partially linear Bayesian modeling of longitudinal rank and time-to-event data using accelerated failure time model with application to brain tumor data.

Joint modeling of longitudinal rank and time-to-event data with random effects model using a Bayesian approach is presented. Accelerated failure time (AFT) models can be used for the analysis of time-to-event data to estimate the effects of covariates on acceleration/deceleration of the survival time. The parametric AFT models require determining the event time distribution. So, we suppose that the time variable is modeled with Weibull AFT distribution. In many real-life applications, it is difficult to determine the appropriate distribution. To avoid this restriction, several semiparametric AFT models were proposed, containing spline-based model. So, we propose a flexible extension of the accelerated failure time model. Furthermore, the usual joint linear model, a joint partially linear model, is also considered containing the nonlinear effect of time on the longitudinal rank responses and nonlinear and time-dependent effects of covariates on the hazard. Also, a Bayesian approach that yields Bayesian estimates of the model's parameters is used. Some simulation studies are conducted to estimate parameters of the considered models. The model is applied to a real brain tumor patient's data set that underwent surgery. The results of analyzing data are presented to represent the method.

COVID-19 and Hospitalization Among Maintenance Dialysis Patients: A Retrospective Cohort Study Using Time-Dependent Modeling.

Rationale & Objective: The coronavirus disease 2019 (COVID-19) pandemic has had a profound impact on hospitalizations in general and on dialysis patients in particular. This study modeled the impact of COVID-19 on hospitalizations of dialysis patients in 2020. Study Design: Retrospective cohort study. Setting & Participants: Medicare patients on dialysis in calendar year 2020. Predictors: COVID-19 status was divided into 4 stages: COVID1 (first 10 days after initial diagnosis), COVID2 (extends until the Post-COVID stage), Post-COVID (after 21 days with no COVID-19 diagnosis), and Late-COVID (begins after a hospitalization with a COVID-19 diagnosis); demographic and clinical characteristics; and dialysis facilities. Outcome: The sequence of hospitalization events. Analytical Approach: A proportional rate model with a nonparametric baseline rate function of calendar time on the study population. Results: A total of 509,609 patients were included in the study, 63,521 were observed to have a SARS-CoV-2 infection, 34,375 became Post-COVID, and 1,900 became Late-COVID. Compared with No-COVID, all 4 stages had significantly greater adjusted risks of hospitalizations with relative rates of 18.50 (95% CI, 18.19-18.81) for COVID1, 2.03 (95% CI, 1.99-2.08) for COVID2, 1.37 (95% CI, 1.35-1.40) for Post-COVID, and 2.00 (95% CI, 1.89-2.11) for Late-COVID. Limitations: For Medicare Advantage patients, we only had inpatient claim information. The analysis was based on data from the year 2020, and the effects may have changed due to vaccinations, new treatments, and new variants. The COVID-19 effects may be somewhat overestimated due to missing information on patients with few or no symptoms and possible delay in COVID-19 diagnosis. Conclusions: We discovered a marked time dependence in the effect of COVID-19 on hospitalization of dialysis patients, beginning with an extremely high risk for a relatively short period, with more moderate but continuing elevated risks later, and never returning to the No-COVID level.

Effects of RU486 in Treatment of Traumatic Stress-Induced Glucocorticoid Dysregulation and Fear-Related Abnormalities: Early versus Late Intervention.

Central glucocorticoid receptor (GR) activity is enhanced following traumatic events, playing a key role in the stress-related cognitive abnormalities of posttraumatic stress disorder (PTSD). GR antagonists are expected to have potential as pharmacological agents to treat PTSD-related symptoms such as anxiety and fear memory disruption. However, an incubation period is usually required and stress-induced abnormalities do not develop immediately following the trauma; thus, the optimal intervention timing should be considered. Single prolonged stress (SPS) was employed as a rodent PTSD model to examine the effects of early or late (1-7 versus 8-14 days after the SPS) sub-chronic RU486 (a GR antagonist) administration. Behaviorally, fear conditioning and anxiety behavior were assessed using the fear-conditioning test and elevated T-maze (ETM), respectively. Neurochemically, the expressions of GR, FK506-binding proteins 4 and 5 (FKBP4 and FKBP5), and early growth response-1 (Egr-1) were assessed in the hippocampus, medial prefrontal cortex (mPFC), amygdala, and hypothalamus, together with the level of plasma corticosterone. Early RU486 administration could inhibit SPS-induced behavioral abnormalities and glucocorticoid system dysregulation by reversing the SPS-induced fear extinction deficit, and preventing SPS-reduced plasma corticosterone levels and SPS-induced Egr-1 overexpression in the hippocampus. Early RU486 administration following SPS also increased the FKBP5 level in the hippocampus and hypothalamus. Finally, both early and late RU486 administration inhibited the elevated hippocampal FKBP4 level and hypothalamus GR level in the SPS rats. Early intervention with a GR antagonist aids in the correction of traumatic stress-induced fear and anxiety dysregulation.

Using fractional polynomials and restricted cubic splines to model non-proportional hazards or time-varying covariate effects in the Cox regression model.

The Cox proportional hazards model is used extensively in clinical and epidemiological research. A key assumption of this model is that of proportional hazards. A variable satisfies the proportional hazards assumption if the effect of that variable on the hazard function is constant over time. When the proportional hazards assumption is violated for a given variable, a common approach is to modify the model so that the regression coefficient associated with the given variable is assumed to be a linear function of time (or of log-time), rather than being constant or fixed. However, this is an unnecessarily restrictive assumption. We describe two different methods to allow a regression coefficient, and thus the hazard ratio, in a Cox model to vary as a flexible function of time. These methods use either fractional polynomials or restricted cubic splines to model the log-hazard ratio as a function of time. We illustrate the utility of these methods using data on 12 705 patients who presented to a hospital emergency department with a primary diagnosis of heart failure. We used a Cox model to assess the association between elevated cardiac troponin at presentation and the hazard of death after adjustment for an extensive set of covariates. SAS code for implementing the restricted cubic spline approach is provided, while an existing Stata function allows for the use of fractional polynomials.

Flexible extension of the accelerated failure time model to account for nonlinear and time-dependent effects of covariates on the hazard.

The accelerated failure time model is an alternative to the Cox proportional hazards model in survival analysis. However, conclusions regarding the associations of prognostic factors with event times are valid only if the underlying modeling assumptions are met. In contrast to several flexible methods for relaxing the proportional hazards and linearity assumptions in the Cox model, formal investigation of the constant-over-time time ratio and linearity assumptions in the accelerated failure time model has been limited. Yet, in practice, prognostic factors may have time-dependent and/or nonlinear effects. Furthermore, parametric accelerated failure time models require correct specification of the baseline hazard function, which is treated as a nuisance parameter in the Cox proportional hazards model, and is rarely known in practice. To address these challenges, we propose a flexible extension of the accelerated failure time model where unpenalized regression B-splines are used to model (i) the baseline hazard function of arbitrary shape, (ii) the time-dependent covariate effects on the hazard, and (iii) nonlinear effects for continuous covariates. Simulations evaluate the accuracy of the time-dependent and/or nonlinear estimates, and of the resulting survival functions, in multivariable settings. The proposed flexible extension of the accelerated failure time model is applied to re-assess the effects of prognostic factors on mortality after septic shock.

Time-varying effect of sex on prognosis of lung adenocarcinoma surgical patients in China.

BACKGROUND: Little is known about the prognostic advantage of sex for pulmonary adenocarcinoma among Chinese patients. In this study, we aimed to investigate the true sex differences in prognosis by adjusting for confounders and to explore whether the differences were time-varying. METHODS: We identified 4438 lung adenocarcinoma patients who underwent surgery at a regional Cancer Center of China from 2008 to 2016, retrospectively. Sex, age group, smoking history, year of diagnosis and pathological stage were collected. Time-dependent Cox regression models with inverse probability of treatment weighting (IPTW) based on propensity score were used to assess the effect of sex and account for confounders. Landmark analyses were conducted to assess survival before, and after, five years. RESULTS: Of these patients, 1761 (39.7%) were men and 2677 (60.3%) were women. Median follow-up time was 52.6 months. After IPTW adjustment, women were found to have significantly better survival than men varying with time in both crude and IPTW models (hazard ratio [HR] [t] = 0.453*1.015t , where t is the length of time from treatment and its unit is month, p < 0.001). Women had significantly better survival than men within 0-5 years after surgery (HR = 0.763, 95% CI: 0.649-0.897, p = 0.001), whereas there was no difference after five years (HR = 1.135, 95% CI: 0.803-1.605, p = 0.472). In subgroup analysis, women in the 61-71+ age group, in the more than 20 year packs group, pathological stage 0-IB group, and 2013-2016 diagnosis period group revealed the same prognostic pattern. CONCLUSIONS: Compared with men, women had better survival after surgical resection of lung adenocarcinoma, especially those who were older and nonsmokers or heavy-smokers and were pathological stage 0-IB in early years, while the advantage for women diminished with time.

Conditional survival in patients with esophageal or gastroesophageal junction cancer after receiving various treatment modalities.

BACKGROUND: To estimate the adjusted conditional overall survival (COS) in patients with esophageal cancer after receiving various treatment modalities via a national population-based database, and to investigate the possible time-dependent effects. MATERIALS AND METHODS: Eligible patients diagnosed with esophageal cancer between 2000 and 2016 were identified from the Surveillance, Epidemiology, and End Results (SEER) registry. The Kaplan-Meier method was used to calculate conventional survival time. The inverse probability of treatment weighting method was used to estimate the adjusted COS in patients receiving different treatment modalities. Landmark analysis was employed to investigate the possible time-dependent effects of different treatment modalities in patients who had survived a certain period of time. RESULTS: A total of 25,232 patients were included in the final analysis. The conventional 5-year overall survival was 19.3%. The 5-year adjusted COS increased most for the first 3 years, and increased slightly afterwards. In patients with regional esophageal or gastroesophageal junction cancer, stage-specific analysis showed that surgery only and preoperative radiation therapy benefited most for patients with localized disease, preoperative radiation therapy plus surgery benefited regional, and preoperative radiation therapy plus surgery benefited distant disease, with the 5-year adjusted COS given patients had survived 3 years being 67.0% (95% CI 65.2%-68.7%), 59.9% (95% CI 58.3%-61.5%), 58.4% (95% CI 56.3%-60.5%), and 61.8% (95% CI 59.5%-64.1%), respectively. In time-dependent analysis, the benefits of surgery only in localized cases were prominent within 48 months after diagnosis. Preoperative radiation therapy showed long-lasting benefits in patients with regional disease. In patients with distant disease, all treatment modalities showed similar and short-term effects. CONCLUSIONS: The adjusted COS in patients with esophageal cancer increased as time accrued after receiving various treatment modalities. The time-dependent effects in specific tumor stage provided a dynamic view on optimization of treatment strategies.

Effect of Plasma Treatment and Its Post Process Duration on Shear Bonding Strength and Antibacterial Effect of Dental Zirconia.

We have investigated the effect of non-thermal atmospheric pressure plasma (NTAPP) treatment and the post process time on the bonding strength and surface sterilization of dental zirconia. Presintered zirconia specimens were manufactured as discs, and then subjected to a 30-min argon treatment (Ar, 99.999%; 10 L/min) using an NTAPP device. Five post-treatment durations were evaluated: control (no treatment), P0 (immediate), P1 (24 h), P2 (48 h), and P3 (72 h). The surface characteristics, shear bonding strength (SBS) with two resin cements, and Streptococcus mutans biofilm formation of these plasma-treated dental zirconia were tested. Plasma did not change the roughness, and caused surface element changes and surface energy increase. Due to this increase in surface energy, SBS increased significantly (p < 0.05) within 48 h when RelyXTM U200 was used. However, the increase of surface oxygen significantly decreased (p < 0.05) the SBS of Panavia F 2.0 when using plasma immediately (P0). S. mutans adhesion decreased significantly (p < 0.05) for the P0, P1, and P2 groups compared to the control. The P0 group exhibited lower biofilm thickness than the other experimental groups due to the increased hydrophilicity (p < 0.05). Our study suggests that there is a suitable time window for the post NTAPP treatment regarding bonding strength and antimicrobial growth persist.

Leucemia inhibitory factor; investigating the time-dependent effect on viability of vitrified bovine embryos.

Leucemia inhibitory factor (LIF) is involved in various reproductive processes, including sperm development, regulation of ovulation, as well as blastocyst formation, hatching and implantation in embryos. Moreover, LIF has also been shown significantly to enhance the blastocyst formation rates of bovine embryos, a finding that remains controversial. Our purpose was to investigate time-dependent effect of LIF on bovine embryo culture, especially in terms of addition timing. Presumptive zygotes were cultured in five different groups. In this study, 100 ng/ml LIF was added to the culture medium were as follows; control: SOF alone, group A: at day 0 (fertilization day), group B: at day 4 post-insemination (p.i.), group C: at day 4 to 7 (p.i. before vitrification) and group D: at day 8 (p.i. after thawing). Addition of LIF to the culture medium at day 4 significantly increased the percentage of blastocyst rate when compared day 0, day 4 at 6/7 and control group (41.8% versus 24.3%, 19.7%, 34.6%). In conclusion, the addition of LIF only on day 4 (p.i.) to the culture medium was found to be beneficial for bovine embryonic development based on several measures, including blastocysts rate, re-expansion rate and cellular cryotolerance after vitrification.

Molecular cloning and expression analysis of immunoglobulin M heavy chain gene of blunt snout bream (Megalobrama amblycephala).

Immunoglobulins (Igs), which bind antigens with high specificity, are essential molecules in adaptive immune system of jawed vertebrates. In this study, cDNA encoding the secreted form of the immunoglobulin heavy chain of IgM (sIgM) was cloned from the mesonephros of blunt snout bream (Megalabrama amblycephala) using RT-PCR and rapid amplification of cDNA ends (RACE). The full-length cDNA of sIgM heavy chain gene has 1961 nucleotides encoding a putative protein of 569 amino acids, constant region shares high amino acid identity with that of Ctenopharyngodon idella (80%), Carassius auratus langsdorfii (65%) and Danio rerio (59%). Multiple protein sequence alignment revealed that blunt snout bream sIgM was clustered with the homologues of cyprinid fish and constructed one clade. Using quantitative real-time PCR (qRT-PCR) analysis, the level of sIgM mRNA was determined, with a V-shape change pattern: decreased initially from unfertilized egg stage to 4 cells stage and increased from 16 cells stage to prelarva. This sharp drop indicates that sIgM mRNA is maternally transferred, and was continuously degraded until 16 cells stage. The drastic rising in sIgM level from blastula stage to prelarva might be attributed to embryonic stem cell differentiation procedure. Compared with juvenile fish, the expression of sIgM was significantly higher in pronephros, liver, spleen, gill and muscle of adult fish. After the injection of Aeromonas hydrophila, the expression pattern of sIgM was found first down-regulated at 4 h, then up-regulated and reached the peak at 7 d and 21 d in mesonephros, spleen, liver and gill, respectively.

Time-dependent effect in green synthesis of silver nanoparticles.

The application of "green" chemistry rules to nanoscience and nanotechnology is very important in the preparation of various nanomaterials. In this work, we successfully developed an eco-friendly chemistry method for preparing silver nanoparticles (Ag-NPs) in natural polymeric media. The colloidal Ag-NPs were synthesized in an aqueous solution using silver nitrate, gelatin, and glucose as a silver precursor, stabilizer, and reducing agent, respectively. The properties of synthesized colloidal Ag-NPs were studied at different reaction times. The ultraviolet-visible (UV-vis) spectra were in excellent agreement with the obtained nanostructure studies performed by transmission electron microscopy (TEM) and their size distributions. The prepared samples were also characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM). The use of eco-friendly reagents, such as gelatin and glucose, provides green and economic attributes to this work.

The time-dependent effect of insulin on the expression of SREBP-1,FAS and lipid droplet formation in HKC cells / 中国药理学通报

Aim To investigate the time-dependent effect of insulin on the expression of SREBP-1(sterol regulatory element binding protein-1),FAS(fat acid synthase)and lipid droplet formation in HKC cells(human renal proximal tubular epithelial cells line).MethodsHKC cells were respectively treated with 100 nmol·L~(-1) insulin for 0,2,4,6,12 h and 24 h.The analysis of SREBP-1 and FAS mRNA was performed by RT-PCR and the expression of SREBP-1 protein was detected by Western blot and immunocytochemistry.Furthermore,Oil Red O staining was used to determine cellular lipid droplet formation.ResultsCompared with HKC cells of 0 h group,there was no difference of SREBP-1 and FAS mRNA in HKC cells of 2 h group.However,the expression of SREBP-1 and FAS mRNA was significantly increased in HKC cells of 4,6 h and 12 h group.Further,the most expression of SREBP-1 and FAS mRNA was at 6 h group and was respectively increased by 3.578 and 4.272 times compared with 0 h group.The results of Western blot showed that the precursor and mature segments of SREBP-1 protein in 4,6 h and 12 h group HKC cells were increased and those of 6 h group HKC cells were the highest and about 4.106 and 5.167 times than those of 0 h group HKC cells.Immunocytochemistry presented the result that SREBP-1 protein was located in the plasma and the expression of 4,6 h and 12 h group HKC cells was significantly higher than that of 0,2 h and 24 h group HKC cells.The result of Oil Red O staining showed that lipid droplet markedly deposited in 6 h group HKC cells,contrarily,no lipid droplet was found in HKC cells of other groups.ConclusionAbove results suggested that insulin up-regulated SREBP-1 and FAS in time-dependent manner that led to cellular lipid droplet deposit,which may play an important role in the pathogenesis of renal lipid accumulation in metabolism syndrome.