The effect of repeated freeze-thaw cycles on the meat quality of rabbit

<p>We investigated the effect of repeated freeze-thaw cycles on the quality of rabbit meat. Twenty-five Hyla rabbits were slaughtered using standard commercial procedures. A freeze-thaw procedure—i.e., seven days frozen at –18°C followed by thawing at 4°C for 12h— was repeated 5 times, and 9 <em>Longissimus thoracis et lumborum</em> muscles were randomly selected at pre-set cycles (0, 1, 2, 3, and 5). The <em>Longissimus lumborum</em> muscles were used to determine meat quality parameters, while the <em>Longissimus thoracis</em> muscles were used for chemical analysis. During the repeated freeze-thaw process, muscle pH, redness, hardness, and water holding capacity gradually decreased, whereas meat lightness and yellowness gradually increased. The amount of total volatile basic nitrogen significantly increased (<em>P</em>&lt;0.05) and exceeded the threshold value for frozen meat after 5 repeated freeze-thaw cycles. The metmyoglobin proportion, thiobarbituric acid-reactive substances (TBARS) and protein carbonyl content in rabbit meat samples increased with a higher number of freeze-thaw cycles (<em>P</em>&lt;0.05), and the proportions of these compounds were positively correlated. During the repeated freeze-thaw process, extractable haeme iron levels significantly decreased (<em>P</em>&lt;0.05), and non-haeme iron levels markedly increased (<em>P</em>&lt;0.05). An sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis indicated that the degradation of both water- and salt-soluble proteins was more prevalent in samples subjected to higher numbers of freeze-thaw cycles. Additionally, a principal component analysis identified good correlations between physicochemical properties (TBARS, protein carbonyl levels and metmyoglobin content) and quality parameters (thawing loss, redness, lightness and hardness). Taken together, we conclude that the repeated freeze-thaw process can strongly affect rabbit meat quality as well as its physicochemical properties.</p>

Nicotine inhibits osteogenic differentiation of human periodontal ligament cells under cyclic tensile stress through canonical Wnt pathway and α7 nicotinic acetylcholine receptor

BACKGROUND AND OBJECTIVES

Nicotine, the main psychoactive component of tobacco, affects cell metabolism, proliferation, adhesion and, importantly, the osteogenic differentiation of fibroblasts. Approximately 15% of all orthodontic patients are adults among who one-fifth are smokers. Hence, it is necessary to have insight into the effects of nicotine on the osteogenic differentiation of hPDLCs during orthodontic tooth movement. This study aimed to investigate the effects and mechanisms of nicotine on the osteogenic differentiation of human periodontal ligament cells (hPDLCs) under the application of cyclic tensile stress.

MATERIAL AND METHODS

hPDLCs were obtained from donor third molars. The hPDLCs were treated with nicotine and/or cyclic tensile stress that was applied with a cell stress plus unit. The effect of nicotine on cell viability was analyzed using the MTT assay. The osteogenic differentiation of hPDLCs was detected by alkaline phosphatase staining, Alizarin Red S staining, quantitative real-time polymerase chain reaction and western blotting.

RESULTS

In combination with cyclic tensile stress, nicotine prevented the tensile stress-induced increase in alkaline phosphatase activity, formation of mineralization nodules and the upregulation of mRNA and protein expression of Runt-related transcription factor 2, transcription factor Sp7 and collagen type I; however, canonical Wnt pathway was activated. Furthermore, the addition of Dickkopf-related protein 1 and α-bungarotoxin counteracted the negative effect of nicotine and rescued the osteogenic differentiation of hPDLCs, respectively.

CONCLUSION

These results indicate that nicotine prevents the increased osteogenic potential of hPDLCs induced by cyclic tensile stress by binding to an α7 nicotinic acetylcholine receptor and activating the canonical Wnt pathway.

Validation of the Chinese version of EORTC QLQ-BN20 for patients with brain cancer

This is a single centre study in mainland China aiming to evaluate the reliability, validity and responsiveness of the Chinese version of EORTC QLQ-BN20, designed by The European Organization for Research and Treatment of Cancer Quality of Life Group to evaluate the life quality of patients with brain tumour, cancer or metastases. One hundred and eighty-eight patients with primary or secondary brain cancer from Hunan Provincial Tumor Hospital during September 2013 to June 2014 completed the Chinese EORTC QLQ-C30/BN20 questionnaires developed by translation, back translation and cultural adaptation. Results were statistically analysed using SPSS17.0. The internal consistency (Cronbach's α coefficient) was between .753 and .869, the correlation coefficients among items and its own dimension were bigger than .4, and all items had a better correlation with its own dimension. The Spearman was used to analyse the correlation of each dimension between EORTC QLQ-BN20 and EORTC QLQ-C30, and the result showed that individual dimensions were moderately correlated, other dimensions were weakly correlated. In conclusion, the Chinese version of EORTC QLQ BN20 questionnaire had great relevance, reliability, convergent validity and discriminant validity. It provides a valuable tool for the assessment of health-related quality of life in clinical studies of Chinese patients with primary or secondary brain cancer.

Effect of delaying colostrum feeding on passive transfer and intestinal bacterial colonization in neonatal male Holstein calves

The objective of this study was to investigate the effect of time of first colostrum feeding on the passive transfer of IgG and on bacterial colonization in the intestine of neonatal dairy calves. Twenty-seven male Holstein calves were randomly assigned to 1 of 3 treatments at birth: calves were fed colostrum at 45 min (0 h, n = 9), 6 h (n = 9), or 12 h after birth (n = 9). Calves were fed pooled, heat-treated colostrum (62 g of IgG/L) at their respective feeding times at 7.5% of birth body weight and fed milk replacer at 2.5% of birth body weight per meal every 6 h thereafter. Blood samples were taken every 3 h using a jugular catheter and were analyzed for determination of serum IgG by radial immunodiffusion. At 51 h after birth, calves were euthanized for collection of tissue and digesta of the distal jejunum, ileum, and colon. Quantitative real-time PCR was used to estimate the prevalence of Bifidobacterium spp., Lactobacillus spp., Fecalibacterium prausnitzii, Clostridium cluster XIVa, and total Escherichia coli. Delaying colostrum feeding by 6 h (35.6 ± 1.88%) and 12 h (35.1 ± 3.15%) decreased the maximum apparent efficiency of absorption of IgG compared with feeding colostrum immediately after birth (51.8 ± 4.18%) and delayed the time to maximum serum IgG concentration (24 h vs. 15 h, respectively). Moreover, 12-h calves tended to have a lower prevalence of Bifidobacterium spp. (0.12 ± 0.017%) and Lactobacillus spp. (0.07 ± 0.019%) associated with the colon mucosa compared with 0-h calves (1.24 ± 0.648% and 0.26 ± 0.075%, respectively). In addition, 6-h (0.26 ± 0.124%) and 12-h (0.49 ± 0.233%) calves had a lower prevalence of total E. coli associated with ileum mucosa compared with 0-h calves (1.20 ± 0.458%). These findings suggest that delaying colostrum feeding within 12 h of life decreases the passive transfer of IgG and may delay the colonization of bacteria in the intestine, possibly leaving the calf vulnerable to infections during the preweaning period.

[Application of the psychological aging scale for healthy people: A preliminary study based on empirical research]

OBJECTIVE

To explore the distribution of psychological aging in healthy population and its relationship with telomere length in peripheral blood leukocyte, and to provide reference for aging evaluation.
 Methods: Stratified random samples were obtained according to age and they were divided into 9 age groups. The age-related psychological information were collected from healthy people by using the self-made scale. Situation of psychological aging, correlation between age and telomere length and score of this scale were analyzed by statistical software.
 Results: A total of 2 100 questionnaires were distributed, and 2 060 of them were valid and has been recovered, with an efficiency of 98.10%. The ratio of male to female was 0.95:1; psychological aging score was in the range of 8.62-23.14; cognitive function score was in the range of 2.25-10.77; emotion score was in the range of 1.45-6.73; personality score was in the range of 0.96-4.22; motivation score was in the range of 1.50-7.18. The correlation coefficient of psychological aging scores with age was 0.721 (P<0.001). The average relative telomere length was 1.06±0.26, and relative telomere length in different age groups were significantly different (F=35.803, P<0.001). Telomere length was negatively correlated with age (r=-0.964, P<0.001) and psychological aging scores (r=-0.915, P=0.004).
 Conclusion: The empirical study of physiological aging scale in healthy population shows that the scores of physical aging are increased with age and that the telomere length is negatively correlated with aging scores, suggesting that the scale can provide reference for the comprehensive evaluation of aging.

A case of severe glutathione synthetase deficiency with novel GSS mutations

Glutathione synthetase deficiency (GSSD) is a rare inborn error of glutathione metabolism with autosomal recessive inheritance. The severe form of the disease is characterized by acute metabolic acidosis, usually present in the neonatal period with hemolytic anemia and progressive encephalopathy. A case of a male newborn infant who had severe metabolic acidosis with high anion gap, hemolytic anemia, and hyperbilirubinemia is reported. A high level of 5-oxoproline was detected in his urine and a diagnosis of generalized GSSD was made. DNA sequence analysis revealed the infant to be compound heterozygous with two mutations, c.738dupG in exon 8 of GSS gene resulting in p.S247fs and a repetitive sequence in exon 3 of GSS gene. Treatment after diagnosis of GSSD included supplementation with antioxidants and oral sodium hydrogen bicarbonate. However, he maintained a variable degree of metabolic acidosis and succumbed shortly after his parents requested discontinuation of therapy because of dismal prognosis and medical futility when he was 18 days old.

Mass transfer dynamics during brining of rabbit meat

As a traditional processing method, brining is a preliminary, critical and even essential process for many traditional rabbit meat products in China. The aim of this work was to investigate mass transfer of rabbit meat brined in different salt concentration. Rabbit meat (Longissimus dorsi) was brined for 24 h in 5 brine solutions (5, 10, 15, 20 and 25% NaCl [w/w]). Results indicated that mass transfer and kinetics parameters were significantly affected by the brine concentration during brining. When brine concentration increased, the total and water weight changes decreased, whereas the sodium chloride weight changes increased. Higher brine concentrations resulted in a higher degree of protein denaturation and consequently gave lower process yields. Samples treated with higher brine concentrations obtained lower brining kinetic parameter values for total weight changes and water weight changes, whereas they acquired higher values for sodium chloride weight changes.

Clinicopathological and prognostic significance of platelet count in patients with ovarian cancer

AIM

Increasing evidence indicates that platelet count is a useful biomarker of long-term outcomes in patients with ovarian cancer. However, the prognostic value of platelet count in patients with ovarian cancer remains controversial. We therefore conducted a meta-analysis aimed to investigate the prognostic role of the platelet count in patients with ovarian cancer.

METHOD

A comprehensive search was performed from the databases of PubMed, Embase and the Cochrane Library until June 20, 2017. A total of 18 studies with 6754 patients were included. Hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) and odds ratios and 95% CIs from each study were pooled.

RESULTS

The results demonstrated that elevated pretreatment platelet count was significantly related to poor survival from ovarian cancer; the pooled HRs for overall, progression-free and disease-free survival were 1.81 (95% CI 1.52-2.15), 1.48 (95% CI 1.24-1.75) and 1.39 (95% CI 1.19-1.61), respectively. Subgroup analyses were divided by ethnicity, sample size, FIGO stage, cut-off value of the platelet count, analysis method and Newcastle Ottawa Scale score, but the results did not show any significant change in the main results. Increased platelet count was also significantly associated with the FIGO stage, tumor differentiation, ascites, residual tumor mass, CA125 level, recurrence and metastasis.

CONCLUSION

This meta-analysis revealed that an elevated platelet count pretreatment denotes a predictive factor of poor prognosis and unfavorable clinicopathological parameters for ovarian cancer patients.

Effects of a short-term feed restriction on growth performance, blood metabolites and hepatic IGF-1 levels in growing rabbits

<p class="Abstract">A total of 144 weaned hybrid HYLA rabbits (40-day-old) were randomly divided into 4 groups, to investigate the effects of the intensity of one week’s feed restriction on short- and medium-term growth performance, blood metabolites and hepatic IGF-1 in growing rabbits. Restricted groups were fed with 30% (Group L30), 50% (Group L50) 70% (Group L70) of ad libitum feeding for 1 wk and then fed ad libitum until the end of the experiment (75 d of age). The control group (Group AL) was fed ad libitum throughout the experiment. Total feed intake (–15.8%) and feed conversion ratio (–13.2%) were lower in the L50 than in the AL group (P&lt;0.05), but no difference was found between the L30, L70 and AL groups (P&gt;0.05) for these parameters. Total weight gain did not significantly differ among the 4 experimental groups (38.5 g/d; P&gt;0.05). At the end of the feed restriction period, the total serum protein level (P=0.01) was higher in restricted rabbits than AL rabbits (P&lt;0.01), while the hepatic IGF-1 level was lower in L30 and L50 groups than in the 2 other groups (P&lt;0.001). However, no difference remained between groups at the end of the experiment. In contrast, calcium, triglycerides, alkaline phosphatase, urea nitrogen and total cholesterol levels were similar between groups (P&gt;0.05) throughout the experiment. In conclusion, a short-term feed restriction improves feed conversion ratio in a lasting way, transiently alters serum protein and IFG-1 levels and leads to compensatory growth in growing rabbits.</p>

Laparoscopic abdominoperineal excision with trans-abdominal individualized levator transection: interim analysis of a randomized controlled trial

AIM

Extralevator abdominoperineal excision (ELAPR) is challenging 'conventional' abdominoperineal excision (APR), yet the safety and efficacy of ELAPR is still under debate. We therefore developed a laparoscopic APR with trans-abdominal individualized levator transection (LAPR-TILT) approach and compared the outcome with a conventional laparoscopic APR (CLAPR).

METHOD

All eligible patients were entered a single-centre randomized controlled trial to compare CLAPR and LAPR-TILT. We assessed the first 185 patients, including operative findings, complications, histopathology and urogenital function.

RESULTS

Ninety-three patients in the CLAPR group and 92 patients in the APR-TILT group were included for analysis. The APR-TILT procedure took less time [137 (101-175) min vs 146 (102-187) min; P = 0.03], mainly owing to faster perineal dissection. APR-TILT resulted in a reduced rate of bowel perforation (1.1% vs 8.6%; P = 0.04), circumferential resection margin positivity (1.1% vs 10.8%; P = 0.01) and postoperative wound complications (5.4% vs 16.2%; P = 0.02) compared with the CLAPR procedure. At a median follow-up of 19 months after surgery, three patients (3.2%) in the CLAPR group had tumour recurrence while no tumour recurrence occurred in the LAPR-TILT group. Patients who underwent LAPR-TILT reported fewer urinary or sexual problems (LAPR-TILT vs CLAPR, 10.9% vs 24.7% and 17.4% vs 38.7%, respectively).

CONCLUSION

Compared with CLAPR, LAPR-TILT achieved better pathological results for factors that are surrogate parameters for local recurrence. LAPR-TILT could also reduce the risk of urogenital dysfunction.

The effect of glucose-dependent insulinotropic polypeptide (GIP) variants on visceral fat accumulation in Han Chinese populations

Objectives:

We aim to validate the effects of glucose-dependent insulinotropic polypeptide (GIP) on fat distribution and glucose metabolism in Han Chinese populations.

Methods:

We genotyped six tag single-nucleotide polymorphisms (SNPs) of GIP and four tag SNPs of glucose-dependent insulinotropic polypeptide receptor (GIPR) among 2884 community-based individuals from Han Chinese populations. Linear analysis was applied to test the associations of these variants with visceral fat area (VFA) and subcutaneous fat area (SFA) quantified by magnetic resonance imaging as well as glucose-related traits.

Results:

We found that the C allele of rs4794008 of GIP tended to increase the VFA and the VFA/SFA ratio in all subjects (P=0.050 and P=0.054, respectively), and rs4794008 was associated with the VFA/SFA ratio in males (P=0.041) after adjusting for the BMI. The VFA-increasing allele of rs4794008 was not related to any glucose metabolism traits. However, rs9904288 of GIP was associated with the SFA in males as well as glucose-related traits in all subjects (P range, 0.004–0.049), and the GIPR variants displayed associations with both fat- and glucose-related traits.

Conclusions:

The results could provide the evidence that GIP might modulate visceral fat accumulation via incretin function or independent of incretin.