Effects Of Different Durations Research Articles

Effect of duration of estradiol exposure on embryo survival and endometrial gene expression in anestrous embryo recipient mares

Previous studies indicate a positive correlation between the duration of estrus prior to ovulation and likelihood of pregnancy in embryo recipient mares. However, the mechanisms by which the duration of estrus before may affect fertility remains unclear. This study aimed to determine the effect of different durations of estradiol exposure, prior to progesterone administration, on embryo viability in anestrous recipient mares, and endometrial expression of genes thought to influence embryo survival. Three groups of anestrous recipient mares treated with different duration of estradiol were used: long (LE), short (SE) and no treatment (NE). Day 8 embryos were transferred into recipient mares four days after long-acting progesterone administration and recovered 48h later to examine embryo growth and viability. The endometrial gene expression profile of selected genes was also investigated. The likelihood of recovering an embryo 48h after transfer was 46.1% (6/13), 62.5% (5/8) and 85.7% (6/7) for recipient mares from the NE, SE and LE groups, respectively (P= 0.09). Embryos recovered from the different groups of recipients did not, however, differ in size, morphology or the proportion of nuclei undergoing mitosis (P>0.05). Abundance of mRNA for uterocalin (P19) and insulin-like growth factor 1 (IGF1) were increased in the LE compared to the NE group, while fibroblast growth factor 2 (FGF2), progesterone receptor (PGR) and insulin-like growth factor 1 receptor (IGF1R) transcript abundances were increased (P<.05) in the NE group compared to both SE and LE groups. In conclusion, a longer exposure of the endometrium to estradiol before progesterone tended to improve embryo survival within 48h of transfer. However, the grade, growth rate, and proportion of mitotic cells in surviving embryos did not differ among groups. If embryos are destined to fail in a suboptimal endometrial environment, they die and disappear quickly. Moreover, a more adequately estradiol-primed uterus, before the progesterone rise, seems to create a uterine environment, in terms of P19, IGF1, FGF2 and PGR gene expression, more conducive to embryo survival and further development.

The effects of different durations of exposure to hypomagnetic field on the number of active mitochondria and ROS levels in the mouse hippocampus

Reactive oxygen species (ROS) are one of the potential molecules in response to a hypomagnetic field (HMF), and exposure to an HMF for eight weeks led to an increase in ROS levels in the whole hippocampus area in mice. ROS are mainly derived from the byproducts of mitochondrial metabolism. However, previous in vivo studies mostly focus on the influence of one time point of HMF exposure on the mouse hippocampus and lack comparative studies on the effects of different durations of HMF exposure on the mouse hippocampus. Here, we investigated the effects of different durations of HMF on the number of active mitochondria and ROS levels in mouse hippocampus. Compared with the geomagnetic field (GMF) group, we found that the number of active mitochondria in the hippocampus was significantly reduced during the sixth week of HMF exposure, whereas the number of active mitochondria was significantly reduced and the ROS levels was significantly increased during the eighth week of HMF exposure. The number of active mitochondria gradually decreased and ROS levels gradually increased in both GMF and HMF groups with prolonged exposure time. In addition, the expression level of the PGC-1α gene in the hippocampus, the main regulator of mitochondrial biogenesis, decreased significantly in the eighth week of HMF exposure. These results reveal that the changes in active mitochondria number and ROS levels were dependent on the durations of HMF exposure, and prolonged exposure to HMF exacerbates these changes.

Effectiveness of Sulfide Balneopeloidtherapy in Patients with Hypertension in Comorbid Combinations: Randomized Prospective Study

INTRODUCTION. In the treatment of cardiovascular diseases, the use of hydrogen sulfide, which is a universal gas transmitter and performs many physiological functions in the body, is of interest.&#x0D; AIM. To evaluate the effectiveness of sulfide balneopeloid therapy (SBPT), carried out at the Klyuchi resort (Perm region), in patients with arterial hypertension (AH), as well as their combinations with coronary heart disease (CHD), prediabetes and cerebrovascular disease (CVD) with chronic ischemia brain (CHM).&#x0D; MATERIALS AND METHODS. A comparative randomized prospective study was conducted at the Klyuchi resort (Perm region), which studied the effectiveness of SBPT in patients with hypertension in various comorbid combinations. General inclusion criteria were the presence of hypertension and age from 40 to 70 years.&#x0D; RESULTS. The results of a study of the effectiveness of different durations of SBPT in patients with hypertension showed that when a course of SBPT was carried out for 14 days, the hypotensive effect was less significant, while mid-term observation revealed that the hypotensive effect after a 21-day course of SBPT persisted for up to 6 months, and after 14-day course — 3 months. In patients with hypertension and prediabetes, complex therapy, including 14 days of SBPT, helps reduce the severity of clinical manifestations and improve quality of life; causes redistribution of fat deposits, improvement of blood pressure profile, aortic compliance, endothelial and neurogenic circuit of skin microcurrent regulation; reduces the serum concentration of vascular endothelial growth factor (VEGF), leptin, and also increases the serum concentration of transforming growth factor beta 1 (TGF-β1). When treating patients with hypertension and coronary artery disease using SBPT, an increase in the activity of the parasympathetic part of the nervous system, a lipid-correcting effect, improvement of endothelium-dependent vasodilation and exercise tolerance. The results of a study of patients with hypertension with CVD and MS showed that patients who received a course of SBRT had a significant improvement in cognitive functions.&#x0D; DISCUSSION. The effects that develop during SBPT are associated with the polymodal effect of the H2S molecule on the main metabolic signaling pathways and regulatory mechanisms of the body’s hormonal-humoral systems, which leads to optimal regulation of micro- and macrohemodynamics, favorable changes in lipid metabolism, trophological status and trophic factors.&#x0D; CONCLUSION. SBPT, carried out at the Klyuchi resort (Perm Region), is effective in patients with hypertension, including various comorbid combinations — hypertension and prediabetes, hypertension and ischemic heart disease, CCI.

Study on the effect of different durations of decalcification and depigmentation on programmed death ligand 1 immunohistochemical staining.

Programmed death ligand 1 (PD-L1) score is an important companion diagnosis to predict the response to immunotherapy. Immunohistochemistry can accurately assess the expression of PD-L1 in routine paraffin-embedded tissue. However, whether decalcified or depigmented tissue is still accurate and can be used as a companion diagnosis is controversial. This study attempts to resolve this controversy by analyzing the effects of decalcification and depigmentation at different times on PD-L1 expression. Placental tissues were selected for tissue microarray, decalcification was performed according to time gradients of 6, 12, 24, 36, and 48 h, and depigmentation was performed according to time gradients of 1, 5, 15, 30, and 60 min. The intensity of PD-L1 expression at different time points was observed and quantified. Ten PD-L1-positive esophageal squamous carcinoma samples were selected for decalcification treatment, and the PD-L1. Combined Positive Score (CPS), Tumor Proportion Score (TPS) and Immunocyte Proportion Score (IPS) and the positivity rates were compared before and after decalcification. After the placenta was decalcified, the intensity of PD-L1 positivity diminished, and the average optical density (AOD) value decreased with the prolongation of decalcification time and decreased significantly (P<0.05) at 24 h compared with the control group, and significantly (P<0.01) at 36 and 48 h compared with the control group. The intensity of PD-L1 positivity was weakened considerably after the treatment with potassium permanganate depigmentation. In addition, the AOD value decreased significantly (P<0.01) after the depigmentation time reached 5 min compared with the control group. Ten cases of PD-L1 positive esophageal squamous carcinoma were treated with 24 h decalcification, although the PD-L1 score decreased to a certain degree (P>0.05), and the positivity rate could reach 90%. After 36 h treatment, PD-L1 scores decreased, the CPS and IPS scores decreased significantly (P<0.05), and the positive rate was only 50%. Potassium permanganate depigmentation significantly reduces PD-L1 expression, even for a shorter time, affecting the accuracy of the results. The accuracy of PD-L1 remained high within 24 h decalcification. The above results have certain reference value for clinical selection of immunotherapy.

Combination chemotherapy with trastuzumab in early-stage breast cancer: a meta-analysis and Bayesian decision analysis of different treatment regimens.

HER2-positive breast cancer is a high-risk malignant tumor, and trastuzumab is an effective targeted therapy drug, but its optimal duration remains uncertain. To compare the efficacy and cost-effectiveness of different durations (6 months, 9 months, 12 months, and 18 months) of trastuzumab combined with chemotherapy in patients with early breast cancer by meta-analysis and Bayesian decision analysis. Randomized controlled trials comparing the effectiveness of different durations of trastuzumab combination chemotherapy in early-stage breast cancer patients were collected by searching multiple databases. Data synthesis was performed using the R software, and a decision tree model was constructed to simulate the expected outcomes and anticipated costs associated with different treatment durations. This study included 9 randomized controlled trials involving 11,328 early-stage breast cancer patients. The meta-analysis results demonstrated that, compared to the control group, trastuzumab combination chemotherapy at different durations significantly improved disease-free survival and overall survival in early-stage breast cancer patients. Among the various treatment durations, it was observed that 12 months of trastuzumab combination chemotherapy, in comparison to other durations, significantly reduced the risk of recurrence and mortality in early-stage breast cancer patients while maintaining a favorable cost-effectiveness ratio. Bayesian decision analysis also confirmed that 12 months of trastuzumab combination chemotherapy is the optimal treatment duration. It is recommended to use 12 months of trastuzumab combination chemotherapy as the standard treatment for early-stage breast cancer patients.

THE EFFECT OF COLD TREATMENT ON THE GERMINATION OF &lt;i&gt;CARDIOCRINUM CORDATUM&lt;/i&gt; VAR. &lt;i&gt;GLEHNII&lt;/i&gt; (LILIACEAE) SEEDS

The seeds of Cardiocrinum cordatum var. glehnii are characterized by a complex morphophysiological type of dormancy. There are three mechanisms of germination inhibition: two of them are localized in the embryo and one in the surrounding structures of the seed. To overcome these mechanisms, different temperature regimes for seed stratification are required.It was revealed that the mechanism of inhibition of embryo postdevelopment is removed at higher temperatures of 18–20°C for 1.5 months for stored seeds or 2 months for fresh ones. Optimal rates of embryo development were observed at 9–10°C. At the end of postdevelopment, the embryos in different experimental variants could significantly differ in length. However, the degree of heterogeneity of the sample by embryo length did not affect the germination rate and the final percentage of germinated seeds.@The temperature regime during embryo postdevelopment did not affect the subsequent growth of the embryonic root and seed germination, as well as cold stratification at the beginning of the experiment did not stimulate embryo growth.The development of embryo root was possible only after exposure to cold (0–2°C). It was demonstrated that the energy of seed germination and the germination rate significantly depend on the duration of cold stratification, regardless of the moment of exposure to cold. The longer the cold treatment was, the faster the seed germination. At the same time, not only cold stratification on water, but also dry storage of seeds at 0–2°C accelerated their germination.Under natural conditions, seed germination of C. cordatum var. glehnii occurs in 18–19 months after dissemination. In laboratory experiment, freshly harvested seeds of this species could be germinated in 7–8 months, taking into account that approximately 4 months of warm stratification are required for the further development of the embryo, and 3.5–4 months of cold stratification are required to remove the mechanism of germination inhibition.Differences in the duration and period of exposure to cold, however, did not affect the final percentage of germinated seeds. In almost all variants, the final percentage of germination was high (from 86 to 100%).The results of the experiment indicate that the process of seed germination of C. cordatum var. glehnii is realized in nature under the effect of different durations of temperature influences, which ensures the plasticity in the reproduction of this species in natural conditions.

Effects of Different Durations and Frequencies of Vestibular Rehabilitation in Patients With Residual Symptoms After Benign Paroxysmal Positional Vertigo Repositioning.

This study aimed to explore the effects of different duration and daily frequency of vestibular rehabilitation (VR) in patients with residual symptoms after benign paroxysmal positional vertigo (BPPV) successful repositioning. Patients with successful BPPV repositioning (n = 118) were divided into 3 groups according to VR duration and frequency: group A (n = 30; 15 minutes, 3 times/day), group B (n = 30; 30 minutes, 3 times/day), group C (n = 28; 15 minutes, 6 times/day), and control group D (n = 30; no VR). All patients completed the dizziness handicap inventory (DHI) and vestibular rehabilitation benefit questionnaire (VRBQ) at baseline and after 2 and 4 weeks. The emotional scores and the proportion of severe dizziness disability in the DHI scores were significant differences between VR groups A to C and control group D after 2 and 4 weeks (all P < .05). There were significant differences in total DHI and VRBQ scores among the VR groups A to C after 2 and 4 weeks (all P < .05). Interestingly, emotion scores were not significantly different in group A (P = .385), group B (P = .569), and group C (P = .340) between 2 and 4 weeks. Meanwhile at 2 weeks, the difference in motion-provoked dizziness score between group A and B was statistically significant (P = .02). A total VR duration over 4 weeks can reduce dizziness and improve VR benefits in routine therapy in patients with residual dizziness after successful BPPV repositioning. Emotional improvement can be observed after 2 weeks. VR may help to relieve motion-provoked dizziness earlier if patients are willing to consider increasing the duration to more than 15 minutes.

Anti-infective therapy durations predict psychological stress and laparoscopic surgery quality in pelvic abscess patients

BACKGROUND The degree of psychological stress and the difficulty and efficacy of laparoscopic surgery differ in patients with pelvic abscesses after different durations of anti-infection treatment. AIM To compare and analyse the effects of different durations of anti-infective therapy on patients’ preoperative psychological stress level and the clinical efficacy of laparoscopic surgery in patients with pelvic abscesses to offer a reference for the selection of therapy plans. METHODS A total of 100 patients with pelvic abscesses who were admitted to the Department of Gynecology of Suzhou Ninth Hospital affiliated to Soochow University (Suzhou Ninth People's Hospital) from January 2018 to December 2022 were retrospectively enrolled. According to the different durations of anti-infective therapy, they were divided into Group S (50 patients, received anti-infective therapy for 24-48 h) and Group L (50 patients, received anti-infective therapy for 48-96 h). Baseline data, state-trait anxiety score at admission and before surgery, self-rating anxiety scale (SAS) + self-rating depression scale (SDS) score, surgery time, adhesion grading score, intraoperative blood loss, presence or absence of intraoperative intestinal injury, ureteral injury or bladder injury, postoperative body temperature, length of hospital stay, and presence or absence of recurrence within 3 mo after surgery, chronic pelvic pain, incision infection, dysmenorrhea, menstrual disorder or intestinal obstruction were compared between the S group and the L group. RESULTS There was no significant difference in the background data between the S group and the L group (P &lt; 0.05). There was no significant difference in the state-trait anxiety score or SAS + SDS score between the S group and the L group on admission (P &lt; 0.05). The state-trait anxiety score and SAS + SDS score of the S group were lower than those of Group L after receiving different durations of anti-infective therapy (P &lt; 0.05). There was no significant difference in the incidence of intestinal, ureteral or bladder injury between the S group and the L group (P &lt; 0.05). The surgery time of Group S was shorter than that of Group L, and the adhesion score and intraoperative blood loss volume were lower than those of Group L (P &lt; 0.05). There was no significant difference in the incidence of incision infection, dysmenorrhea, menstrual disorder or intestinal obstruction between the S group and the L group (P &lt; 0.05). The postoperative body temperature of Group S was lower than that of Group L (P &lt; 0.05), and the hospital stay was shorter than that of Group L (P &lt; 0.05). The incidences of recurrence and chronic pelvic pain within 3 mo after surgery were lower than that of Group L (P &lt; 0.05). CONCLUSION Twenty-four to forty-eight hours of anti-infective therapy is better than 48-96 h of anti-infective therapy for patients with pelvic abscesses because the degree of psychological stress is lower, which is more conducive to achieving better outcomes after laparoscopic surgery.

Novel star-shaped liquid crystal macromolecules based on conjugated structures of azo and Schiff bases: synthesis and properties

ABSTRACT In this paper, a series of novel liquid crystal units (ASE-n, n = 4, 6, 8) of azo Schiff bases with sulphonic acid (-SO3H) as terminal substituents and different alkyl chain lengths were designed and synthesised. Nine star-shaped liquid crystal macromolecules with different central groups (ASE-P-n, ASE-T-n, ASE-G-n, n = 4, 6, 8) were synthesised by esterification of three novel azo Schiff base liquid crystal units (ASE-n, n = 4, 6, 8) with phloroglucinol, pentaerythritol and glucose. The structure of the synthesised compounds were analysed by infrared spectroscopy and 1H NMR. The results showed that all the compounds were consistent with the molecular structure design. The properties of liquid crystal such as phase transition temperature and liquid crystal mesophase range were characterised by POM and DSC. The effects of alkyl chain length and branched degree on the properties of liquid crystal were studied. The maximum absorption spectrum of the compound was determined by UV-Vis spectrophotometry. The photoisomerisation reaction of the compound was also studied. Under ultraviolet light (λ = 365 nm) irradiation, the effect of different duration on the cis-absorption percentage of azo (-N=N-) bond in the compound was studied.

Damage assessment in a wheel steel under alternated dry-lubricated contact by an innovative vision system

The alternation of dry and wet contact causes a complex interaction of various damage mechanisms in railway wheels. To study the damage evolution in such condition, rolling-sliding contact tests in alternated dry-wet contact were carried out by a bi-disc machine on specimens extracted from railway wheels. The effect of different durations of the dry and wet sessions was investigated. Two kinds of tests were done: in one case coupling two cylindrical specimens, in the other one coupling a cylindrical specimen with a crowned one. The surface appearance during the tests was acquired by a vision system; the acquired images were elaborated to extract quantitative damage indexes. At the end of the tests, the specimens were cut and analysed, to evaluate the subsurface damage and the strain hardening.In cylindrical-cylindrical coupling, the damage increased in alternated dry-wet sessions as far as the cycle number increased, whereas it was stabilized in long dry sessions. The prevailing phenomenon, occurring during the wet sessions, was fatigue, promoted by the pressurization of the water entrapped in the cracks previously formed in dry contact.In crowned-cylindrical couplings, the damage tended to decrease as far as the cycles increased, in all the test conditions. This was correlated to the widening of the contact patch caused by wear, which led to an overall stress relaxation, this way mitigating the damage.The results highlighted the double role of wear, which alters the optimum wheel profile, but at the meantime relaxes the overall stress state and mitigates rolling contact fatigue.

Effect of thermophilic composting duration on vermiconversion of olive mill wastewater using Eisenia andrei

This study aimed to investigate the effect of different durations of thermophilic composting (TC) on the enhancement of vermicomposting of olive mill wastewater (OMWW). Four mixtures consisting of olive cake, horse manure, and wheat straw, soaked with varying ratios of OMWW (0 %, 25 %, 50 %, and 75 %), were subjected to TC. Following TC durations of 15, 30, 45, and 60 days, the mixtures underwent vermicomposting. Overall, each OMWW ratio demonstrated an optimal TC duration that resulted in maximum earthworm performance. As the OMWW ratio increased, the optimal TC duration extended from 30 to 60 days. The combined TC and vermicomposting process exhibited a final C/N ratio of 13.5 and 95 % decrease in phenolic compounds. The germination index confirmed higher phytostimulant effect of the final product. These findings highlight the positive role of the optimal TC duration allowing the vermicomposting of a substantial quantity of OMWW, thus contributing to olive wastes treatment.

Effects of physical activity combined with different visual target presentation durations of ciliary-muscle training on visual acuity in children.

This study aimed to identify the effect of different durations of visual target presentation during ciliary-muscle training on children's kinetic visual acuity (KVA), uncorrected distance visual acuity (UDVA), axial length, and accommodative facility. Based on the ciliary-muscle regulation mechanism, an intervention program involving ciliary-muscle training with different durations of visual target presentation combined with physical education classes was designed. The intervention aimed to determine the effect of different ciliary-muscle training durations on children's visual acuity. A total of 153 children aged 10-11 years from a school in Suzhou (a major city located in southeastern Jiangsu Province, East China) were enrolled as participants in this 32-week intervention study. This study measured the participants' UDVA and KVA before, during (after the 16th week), and after (after the 32nd week) the experimental intervention. The accommodative facility was measured during and after the intervention. After 32 weeks of the intervention, the KVA and UDVA of each experimental group were significantly improved (p < 0.05). A high percentage in the improvement of KVA was observed in the 3-s and 1-s groups (25.53%, 21.74%), and the highest percentage in the improvement of UDVA was observed in the 3-s group (2.96%). Axial length increased significantly in all groups (p < 0.05), and there was a low percentage increase in the 1-s and 3-s groups (0.82%). The accommodative facility was significantly improved in all experimental groups, with a higher improvement percentage in the 3-s and 1-s groups (3.01% and 2.61%, respectively). After dividing the children in each group according to their visual acuity, the KVA of children in the 1-s group was significantly improved, the UDVA of children with myopia was significantly increased, and the accommodative facility of children with mild and moderate myopia was significantly improved. Moreover, the KVA, UDVA, and accommodative facility of children with mild and moderate myopia in the 3-s group were significantly improved. The KVA of children with emmetropia and the accommodative facility of children with mild and moderate myopia in the 5-s group were also significantly increased. In school physical education classes, the 1-s, 3-s, and 5-s ciliary-muscle regulating exercise could effectively improve the kinetic visual acuity, uncorrected distance visual acuity, and accommodative facility of children aged 10-11 years. Among them, the effects of the 1-s and 3-s durations are better than that of the 5-s duration, as it can reduce the growth rate of axial length and achieve better effects among children with mild and moderate myopia.

The Effects of Phased Warming during Late Winter and Early Spring on Grain Yield and Quality of Winter Wheat (Triticum aestivum L.)

Phased warming in late winter and early spring can increase winter wheat grain yield. However, the effects of different durations of warming during this period on winter wheat grain yield and quality are not yet clear. Therefore, this study conducted field warming experiments in a movable polyethylene greenhouse during the late winter and early spring stages of the three wheat growing seasons from 2019 to 2022. The results showed that the accumulated growing degree days (GDD) of the warming treatment during the warming period were increased by 87.3–215.7 °C d compared to the control (CK). The warming treatment advanced and prolonged the duration of vegetative growth and spike differentiation after regreening, promoted spike and flower development, and increased grain length, grain width, and grain area. During the three growing seasons, the longer the warming duration (WD) of the warming treatment, the more obvious were the observed promoting effects on the kernel number per spike and 1000-kernel weight. From 2019 to 2021, compared to the CK, the spike number per unit area and grain yield of the warming treatments increased with the prolongation of WD. However, in the 2022 growing season the spike number per unit area and grain yield of the warming treatment were increased with longer WD, reaching the maximum at WD of 56 days and then gradually decreasing with longer WD. Compared to CK, the grain protein content, wet gluten content, and sedimentation value of the warming treatment decreased with the prolongation of WD. The promotion effect of longer WD on grain starch content and protein yield was more significant. In summary, the accumulated GDD during the warming period compared to CK was 155.8–181.2 °C d, and at WD of 50–56 days a relatively higher grain yield and protein yield could be obtained.

Striking a balance: how long physical activity is ideal for academic success? Based on cognitive and physical fitness mediation analysis.

Balancing physical activity and studying is an important issue facing Chinese teenagers. Therefore, numerous studies have found that engaging in physical activity can promote academic performance among students. However, what is the optimal duration of physical activity? This study used data from the China Education Panel Survey, with a sample size of 18,009 valid respondents. General linear regression analysis was conducted using Stata 17 software to evaluate the effects of different durations of physical activity, cognitive ability, and physical Fitness on academic performance among adolescents. Furthermore, the "Bootstrap Mediation" method and the "Maximum Likelihood Estimation" method were used to analyze whether physical health and cognitive ability have significant mediating effects. The present study reveals the following findings: (1) There exists a non-linear relationship between students' academic performance and the duration of physical exercise. The greatest improvement in academic performance is observed when the exercise duration reaches 2 hours. (2) Physical exercise can enhance students' academic performance by promoting physical health and cognitive abilities. (3) Gender heterogeneity is observed, with the optimal exercise duration for male students being 2 hours, while female students exhibit the highest academic performance when exercising for one hour. This study provides theoretical guidance for research on adolescents' participation in physical Activity and improving academic performance, enabling adolescents to engage in physical Activity more scientifically and rationally.

Effects of aerobic exercises in prediabetes patients: a systematic review and meta-analysis.

To evaluate the effects of different durations of continuous aerobic exercise on prediabetic patients. The research encompassed randomized controlled trials that examined how various durations of aerobic exercise training affected outcomes related to Body Mass Index (BMI), Fasting blood glucose (FBG), 2-hour plasma glucose (2hPG), and glycated hemoglobin (HbA1c) in individuals diagnosed with prediabetes. PubMed, Embase, Web of Science, and the Cochrane Library were searched as of January 7, 2023. The Cochrane Risk of Bias, version 2 (ROB 2) tool was used to assess the risk of bias. A total of 10 RCTs with 815 prediabetic patients were included. The average age of the participants was 56.1 years, with a standard deviation of 5.1 years. Among the participants, 39.2% were male. The interventions consisted of aerobic dance, treadmill running, walking, and a combination of aerobic exercises. The training sessions occurred three or four times per week. In prediabetic patients, aerobic exercise demonstrated a significant reduction in BMI compared to the control group, with a weighted mean difference (WMD) of -1.44 kg/m2 (95% confidence interval [CI] -1.89, -0.98). There was a decrease in FBG levels, with WMD of -0.51 mmol/L (95% CI -0.70, -0.32). Additionally, aerobic training led to significant improvements in 2hPG levels, with a WMD of -0.76 mmol/L (95% CI -1.14, -0.38). Furthermore, prediabetic patients showed a decrease in HbA1c levels after engaging in aerobic training compared to the control group, with a WMD of -0.34% (95% CI -0.45, -0.23). In summary, engaging in aerobic exercise can have a significant positive impact on glycemic levels in individuals with prediabetes. It can also lead to reductions in BMI, FBG, 2hPG, HbA1c, and other relevant indicators. The extent of these improvements may vary slightly depending on the duration of the aerobic exercise intervention. PROSPERO https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023395515.

Effect of Short versus Long Duration Naps on Blood Pressure during Simulated Night Shift Work: A Randomized Crossover Trial

Objective Blunting of the sleep-related dip in blood pressure (BP) has been linked to numerous cardiovascular outcomes including myocardial infarction. Blunting of BP dipping occurs during night shift work and previous research suggest that a 60-min or longer on-shift nap is needed to restore normal/healthy BP dipping. We sought to determine the effect of different durations of napping on BP during and following simulated night shifts. We hypothesized that the greatest benefit in terms of restoration of normal BP dipping during night shift work would be observed during a longer duration nap versus a shorter nap opportunity. Methods We used a randomized crossover laboratory-based study design. Participants consented to complete three separate 72-hr conditions that included a 12-hr simulated night shift. Nap conditions included a 30-min and 2-hr nap compared to a no-nap condition. Ambulatory BP monitoring was assessed hourly and every 10-30 mins during in-lab naps. Blunted BP dipping during in-lab naps was the primary outcome. Goal enrollment of 25 (35 with attrition) provided 80% power to detect a mean difference of 5 mmHg in BP between nap conditions. Results Of the 58 screened, 28 were consented, and 26 completed all three 72-hr conditions. More than half (53.6%) were female. Mean age was 24.4 years (SD7.2). Most (85.7%) were certified as emergency medical technicians or paramedics. The mean percentage dip in systolic BP (SBP) and diastolic BP (DBP) did not differ between the 30-min and 2-hr nap conditions (p > 0.05), yet a greater proportion of participants experienced a 10-20% dip in SBP or DBP during the 2-hr nap versus the 30-min nap (p < 0.05). For every additional minute of total sleep during the 30-min nap, the percentage of SBP dip improved by 0.60%, and the percentage of DBP dip improved by 0.68% (p < 0.05). These improvements approximate to a 6% per minute relative advancement toward normal/healthy BP dipping. Conclusions Restoration of a normal/healthy dip in BP is achievable during short and long duration nap opportunities during simulated night shift work. Our findings support the hypothesis that BP dipping is more common during longer 2-hr versus shorter 30-min naps. Trial registration ClinicalTrials.gov, NCT04469803. Registered on 9 July 2020.

Effects of transportation duration on lying behavior in young surplus dairy calves

Surplus dairy calves are commonly transported long distances from dairy farms to calf-raising facilities and livestock auctions. Current calf transportation research mainly describes physiological changes resulting from transportation. However, few studies have described the impact of transportation on calf behavior. The main objective of this study was to determine the effect of different durations of transportation (6, 12, and 16 h) on lying time and bouts in surplus dairy calves. A secondary objective of this study was to investigate if calf age affected lying behavior around transportation. Surplus dairy calves (n = 175) were transported in 7 cohorts from 5 commercial dairy farms in Ontario to a single veal facility. On the day of transportation (d 0), calves were randomly assigned to one of 3 treatment groups: 1) 6 h (n = 60), 2) 12 h (n = 58), and 3) 16 h (n = 57) of continuous transportation by road. Calf lying and standing behavior was recorded using HOBO data loggers. Daily lying time (h/d) and bouts (no./d) were assessed from -1 to 3 d relative to transportation. The total time spent lying during transportation was assessed as the percentage of time lying (min lying/total min on the trailer × 100) from the time each calf was loaded onto the trailer until the time each calf was unloaded at the veal facility (n = 167). On the day of transportation (d 0), calves transported for 12 and 16 h spent less time lying (6 h: 17.1 h/d; 12 h: 15.9 h/d; 16 h: 15.0 h/d) and had more lying bouts (6 h: 21.9 bouts/d; 12 h: 25.8 bouts/d; 16 h: 29.8 bouts/d) compared with those transported for 6 h. On the day after transportation (d 1), calves transported for 16 h spent more time lying down than calves transported for 6 h (19.9 h/d vs. 18.8 h/d, respectively). In addition, during transportation, calves transported for 12 h and 16 h spent 5.8% and 7.6% more time lying down, respectively, than calves transported for 6 h. On each day relative to transportation (d -1 to 3), younger calves (2 d to 5 d) spent a greater amount of time lying down than older calves (6 d to 19 d) and, overall, had a greater number of lying bouts. The results of this study suggest that longer durations of transportation have an impact on the lying behavior of surplus dairy calves resulting in more fatigue during and after the journey, and therefore, potentially have negative implications on calf welfare. Additionally, longer durations of transportation may be more impactful on younger calves than older calves.

Abstract P2-07-02: Effects of different duration of prophylactic antibiotic use on unplanned reoperation in breast cancer patients undergoing implant-based breast reconstruction: A retrospective study with overlap weighting analysis

Abstract Background: Some special consensus recommended the duration of perioperative antibiotic prophylaxis was within 24 hours postoperatively in breast cancer undergoing postmastectomy implant breast reconstruction. However, surgeons in practice favored to prolong the duration. The aim of this study was to estimate the effects of duration of antibiotics on major adverse outcomes in real clinical practice setting with diverse population using overlap weighting model. Methods: In this retrospective study, patients with breast cancer undergoing breast implant reconstructions were collected in Fudan University Shanghai Cancer Center from 1 January 2008 to 31 December 2021. Cases were divided into two groups according to the duration of perioperative antibiotic prophylaxis: short-term group (≤ 24 hours) and long-term group (&amp;gt;24 and≤48 hours). The primary outcomes were unplanned reoperations and complication-related unplanned reoperations. Unplanned reoperation was defined as debridement, expander removal without prosthesis implantation, expander removal and expander implantation, prosthesis removal and prosthesis implantation, prosthesis removal, prosthesis removal and expander implantation. By reviewing the patients’ detailed medical history, all unplanned reoperations were divided into non-complication-related unplanned reoperations and complication-related unplanned reoperations. Non-complication-related unplanned reoperations included: patients voluntarily gave up continuing reconstruction, suspected recurrence of cancer, changed reconstruction methods, unsatisfactory appearance, and unknown reasons. Complication-related unplanned reoperations included: infection, exposure of prosthesis or expander, poor wound healing, rupture of expander, necrosis of skin flap, bleeding. The secondary outcomes were infections that required intervention. It was defined as both met with white blood cells elevation and physician antibiotic prescription during outpatient follow-up. To adjust confounders, propensity score overlap weighting was used, and subgroup analysis and sensitive test were conducted to demonstrate the robustness of results. A P value less than 0.05 was considered statistically significant. Results: In 4367 cases of unilateral implant reconstructions, 4128 (95%) were included in this study. Among them, 1689 were expander implantation, 1124 were prosthesis implantation and 1315 were expander removal and prosthetic implantation. At inclusion, only 283 cases (6.9%) received antibiotics prophylaxis ≤24 hours, 3090 cases (74.9%) with duration &amp;gt;24 and≤48 hours, and 755 cases (18.3%) with duration &amp;gt;48 hours. Of them, 230 cases (5.6%) underwent unplanned reoperation, including 131 (3.2%) complication-related unplanned reoperations, and 99 (2.4%) non-complication-related unplanned reoperations. And there were 110 cases (2.7%) with infections that required intervention. In unweighted or weighted data set, short-term antibiotic use did not significantly increase the risk of adverse outcomes, including unplanned reoperation, complication-related unplanned reoperation, and infection required intervention, compared with long-term antibiotic use with or without patients with duration more than 48 hours. Most subgroup analysis showed no evidence of heterogeneity of the effects of duration of antibiotic use on adverse outcomes. Conclusion: In clinical setting with diverse population, prolong antibiotic prophylaxis with more than 24 hours is not necessary to reduce major adverse outcomes, even in some critical conditions. Appropriating and accessible prophylactic initiatives should be developed and implemented with shorten the duration of antibiotic prophylaxis and minimized adverse outcomes. Key words: perioperative antibiotic prophylaxis, breast cancer, postmastectomy implant reconstruction, unplanned reoperation Citation Format: Zeqing Li, Jiajian Chen, Shuang Hao, A-Yong Cao, Xiaoyan Huang, Zhiming Shao, Jiong Wu. Effects of different duration of prophylactic antibiotic use on unplanned reoperation in breast cancer patients undergoing implant-based breast reconstruction: A retrospective study with overlap weighting analysis [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P2-07-02.

Effect of Different Durations of Adjuvant Capecitabine Monotherapy on the Outcome of High-Risk Stage II and Stage III Colorectal Cancer: A Retrospective Study Based on a CRC Database.

(1) Background: The duration of adjuvant chemotherapy recommended by the NCCN guidelines is 6 months. However, patients are not compliant with intravenous chemotherapy for many reasons; therefore, one approach is to obtain a survival benefit by prolonging the duration of capecitabine monotherapy. (2) Methods: A total of 355 qualified colorectal cancer (CRC) patients from January 2010 to December 2020 at West China Hospital of Sichuan University were selected to receive capecitabine monotherapy for 6−9 months and >12 months. The main endpoints were overall survival (OS) and disease-free survival (DFS). (3) Results: Among stage III patients, in the >12 months (12M) and 6−9 months (6M) groups, the 5-year DFS rates were 80.7%% and 66.8%, respectively, and the 5-year OS rates were 94.7%% and 88.8%, respectively. Among high-risk stage II patients, in the >12 months (12M) and 6−9 months (6M) groups, the 5-year DFS rates were 81.5% and 78.6%, respectively, and the 5-year OS rates were 93.1% and 84.2%, respectively. (4) Conclusions: Twelve months of chemotherapy demonstrated superior OS and DFS to that of six months in the stage III group but showed no difference in the high-risk stage II group. The better OS and DFS observed in the 12-month treatment period could be of value in selected cases.

Effect of Different Durations of Home Bleaching on Tooth Discoloration Caused by Mineral Trioxide Aggregate: An In Vitro Study

Effect of Different Durations of Home Bleaching on Tooth Discoloration Caused by Mineral Trioxide Aggregate: An In Vitro Study