Effect of Akt activation on apoptosis-related gene expression in the crop tissues of male and female pigeons (Columba livia)

The current study investigated whether the expression of apoptosis genes in the pigeon crops was affected by the Akt signaling pathway during crop milk formation. First, 78 pairs of adult White King pigeons were randomly assigned to 7 groups, and the expression of apoptosis-related genes and Akt signaling pathway-related proteins in the crop tissues during different breeding stages were examined. The results showed that the mRNA levels of Bak, caspase-3, caspase-6, and caspase-9 in female crops all increased and reached their highest levels at d 17 of incubation (I17). In male crops, the levels of caspase-3 and caspase-9 gene expression peaked at d 1 of chick rearing (R1). The lowest level of Bcl-2 gene expression in females was observed at I17. The expression ratios of p-Akt (Ser473)/Akt and p-Akt (Thr308)/Akt in male crops decreased to their minimum at R1, while it was observed at d 7 of chick rearing (R7) in females. Second, 36 pairs of adult pigeons were divided into 3 groups and were subjected to SC79 injections with dosages of 0, 0.02, or 0.04 mg/kg bodyweight. The SC79 injections resulted in a considerable decrease in growth performance of pigeon squabs. In male crops, the expression ratios of p-Akt (Ser473)/Akt and p-Akt (Thr308)/Akt were significantly elevated in the 0.02 mg/kg SC79 group, while in female crops, they were higher in the 0.04 mg/kg SC79 group (P < 0.05). The SC79 injection inhibited the gene expression of Bak in female crops, but enhanced the gene expression of Bcl-2 in both male and female crops. In the 0.04 mg/kg SC79 group, a 50.7 to 75.7% decrease was observed in the expression of caspase-3, caspase-6, and caspase-9 in male and female pigeon crops. Expression of the caspase-8 gene and total Akt protein in pigeon crops was not changed in different breeding stages or after SC79 injection. In conclusion, the expression of genes related to mitochondria-dependent apoptosis can be regulated by the Akt signaling pathway, which may play a potential role in pigeon milk formation.

[Long-term efficacy and safety of simultaneous integrated boost radiotherapy in non-operative esophageal squamous cell carcinoma: a multicenter retrospective data analysis (3JECROG R-05)]

Objective: To analyze the survival benefits and treatment related toxic effects of simultaneous integrated boost intensity-modulated radiotherapy (SIB-RT) for non-operative esophageal squamous cell carcinoma patients. Methods: The data of 2 132 ESCC patients who were not suitable for surgery or rejected operation, and underwent radical radiotherapy from 2002 to 2016 in 10 hospitals of Jing-Jin-Ji Esophageal and Esophagogastric Cancer Radiotherapy Oncology Group (3JECROG) were analyzed. Among them, 518 (24.3%) cases underwent SIB (SIB group) and 1 614 (75.7%) cases did not receive SIB (No-SIB group). The two groups were matched with 1∶2 according to propensity score matching (PSM) method (caliper value=0.02). After PSM, 515 patients in SIB group and 977 patients in No-SIB group were enrolled. Prognosis and treatment related adverse effects of these two groups were compared and the independent prognostic factor were analyzed. Results: The median follow-up time was 61.7 months. Prior to PSM, the 1-, 3-, and 5-years overall survival (OS) rates of SIB group were 72.2%, 42.8%, 35.5%, while of No-SIB group were 74.3%, 41.4%, 31.9%, respectively (P=0.549). After PSM, the 1-, 3-, and 5-years OS rates of the two groups were 72.5%, 43.4%, 36.4% and 75.3%, 41.7%, 31.6%, respectively (P=0.690). The univariate survival analysis of samples after PSM showed that the lesion location, length, T stage, N stage, TNM stage, simultaneous chemoradiotherapy, gross tumor volume (GTV) and underwent SIB-RT or not were significantly associated with the prognosis of advanced esophageal carcinoma patients who underwent radical radiotherapy (P<0.05). Cox model multivariate regression analysis showed lesion location, TNM stage, GTV and simultaneous chemoradiotherapy were independent prognostic factors of advanced esophageal carcinoma patients who underwent radical radiotherapy (P<0.05). Stratified analysis showed that, in the patients whose GTV volume≤50 cm(3), the median survival time of SIB and No-SIB group was 34.7 and 30.3 months (P=0.155), respectively. In the patients whose GTV volume>50 cm(3), the median survival time of SIB and No-SIB group was 16.1 and 20.1 months (P=0.218). The incidence of radiation esophagitis and radiation pneumonitis above Grade 3 in SIB group were 4.3% and 2.5%, significantly lower than 13.1% and 11% of No-SIB group (P<0.001). Conclusions: The survival benefit of SIB-RT in patients with locally advanced esophageal carcinoma is not inferior to non-SIB-RT, but without more adverse reactions, and shortens the treatment time. SIB-RT can be used as one option of the radical radiotherapy for locally advanced esophageal cancer.

[Laparoscopic circular stapled gastrointestinal anastomosis using novel device of sealed cap access after total laparoscopic gastrectomy]

Intracorporeal classic gastrointestinal anastomosis using circular stapler in totally laparoscopic gastrectomy (TLG) for gastric cancer requires intracorporeal anvil placement and suitable access for introduction of the circular stapler to the abdominal cavity without gas leak. The novel techniques for anvil placement have been updated, but there is no progress for proper access for circular stapler. In the study, intracorporeal circular-stapled gastrointestinal anastomosis were successfully accomplished using a novel device of sealed cap access with a central hole (WLB-60/70-60/100, Wuhan Widerep Medical Instrument Co.,Ltd, China) customized to the incision protection retractor for the simple and accessible introduction of the circular stapler and anvil under the optimal maintenance of pneumoperitoneum pressure in TLG. In these 3 cases, there was no gas leakage and the pneumoperitoneum was well maintained when performing the gastrointestinal anastomosis, and there was no transition to laparotomy or other anastomosis techniques. The result suggests that the sealed cap access could be a novel choice for introduction of the circular stapler to the abdominal cavity in order to obtain laparoscopic circular-stapled gastroin-testinal anastomosis in TLG.

[Efficacy analysis of the radiotherapy and chemotherapy in patients with stage Ⅳ esophageal squamous carcinoma: a multicenter retrospective study of Jing-Jin-Ji Esophageal and Esophagogastric Cancer Radiotherapy Oncology Group (3JECROG R-01F)]

Objective: To evaluate the survival and prognostic factors of radiotherapy in patient with Ⅳ stage esophageal squamous carcinoma treated with radiation or chemoradiation. Methods: The medical records of 608 patients with stage Ⅳ esophageal squamous cell carcinoma who met the inclusion criteria in 10 medical centers in China from 2002 to 2016 were retrospectively analyzed. The overall survival and prognostic factors of all patients at 1, 3 and 5 years were analyzed. Results: The 1-, 3-, 5- year overall survival (OS) rates was 66.7%, 29.5% and 24.3% in stage ⅣA patients, and 58.8%, 29.0% and 23.5% in stage ⅣB patients. There was no statistical difference between the two groups (P=0.255). Univariate analysis demonstrated that the length of lesion, treatment plan, planned tumor target volume (PGTV) dose, subsequent chemotherapy, and degrees of anemia, radiation esophagitis, radiation pneumonia were related to the prognoses of patients with Ⅳ stage esophageal carcinomas after radiotherapy and chemotherapy (P<0.05). Multivariate analysis demonstrated that PGTV dose (OR=0.693, P=0.004), radiation esophagitis (OR=0.867, P=0.038), and radiation pneumonia (OR=1.181, P=0.004) were independent prognostic factors for OS. Conclusions: For patients with stage Ⅳ esophageal squamous cell carcinoma, chemoradiotherapy followed by sequential chemotherapy is recommended, which can extend the total survival and improve the prognosis of the patients. PGTV dose more than 60 Gy has better efficacy.

[CT manifestations and prognosis of acute paraquat induced lung injury]

Objective: To investigate the CT features of lung injury induced by paraquat poisoning and its relationship with prognosis, and to provide reference for the judgment of the condition and prognosis of paraquat poisoning. Methods: 146 cases of paraquat poisoning patients were treated in the Third People's Hospital of Xuzhou City from January 2013 to April 2016. The cases were divided into mild group, moderate-severe group and fulminant group according to the concentration of paraquat in urine. The clinical data and CT imaging findings were analyzed and reconstructed in three-dimensional reconstruction. The extent of the lesion was observed and the relationship between CT and prognosis was explored. Results: Paraquat lung injury has many manifestations on CT images, and it's performance can be intersecting at the same time. Early lesions lighter cases, late CT imaging lesions can be completely absorbed or residual fibrosis, the prognosis was good; the early lesion was pulmonary consolidation, pleural effusion cases, the late CT image was usually pleural thickening and bronchiectasis, the prognosis was relatively good; early lesions were large patches of ground glass opacity cases, finally, pulmonary fibrosis was common, the mortality rate of 56.57%. There were significant differences in the extent of lung injury between different groups (P<0.001) , and the difference in mortality was statistically significant when the lung injury was different (P<0.001) . Multivariate stepwise Logistic regression analysis showed that ground-glass opacity (OR value=2.013) , interstitial lung fibrosis (OR=3.779) and mediastinal emphysema (OR=33.118) were risk factors for death of lung injury caused by paraquat poisoning (P<0.05) . Conclusion: There were many manifestations on CT images of paraquat lung injury, and the manifestations of paraquat lung injury can be intersecting at the same time. The pulmonary manifestations and outcomes of different paraquat types were different. The CT manifestations of lung injury in paraquat poisoning were mainly exudative changes at early stage, and can be gradually absorbed or evolved into interstitial changes at later stage. The cumulative damage range can be used as a reference for evaluating the prognosis. Ground-glass opacity, interstitial pulmonary fibrosis and mediastinal emphysema are the risk factors for death of lung injury caused by paraquat poisoning.

[Prognostic analysis of definitive radiotherapy for early esophageal carcinoma(T1-2N0M0): a multi-center retrospective study of Jing-Jin-ji Esophageal and Esophagogastric Cancer Radiotherapy Oncology Group]

Objective: To evaluate the prognostic factors of T1-2N0M0 esophageal squamous cell carcinoma (ESCC) treated with definitive radiotherapy. Methods: The clinical data of 196 patients with T1-2N0M0 ESCC who were treated with definitive radiotherapy in 10 hospitals were retrospectively analyzed. All sites were members of Jing-Jin-Ji Esophageal and Esophagogastric Cancer Radiotherapy Oncology Group (3JECROG). Radiochemotherapy were applied to 78 patients, while the other 118 patients received radiotherapy only. 96 patients were treated with three-dimensional conformal radiotherapy (3DCRT) and 100 treated with intensity-modulated radiotherapy (IMRT). The median dose of plan target volume(PTV) and gross target volume(GTV) were both 60 Gy. The median follow-up time was 59.2 months. Log rank test and Cox regression analysis were used for univariat and multivariate analysis, respectively. Results: The percentage of normal lung receiving at least 20 Gy (V(20)) was (18.65±7.20)%, with average dose of (10.81±42.05) Gy. The percentage of normal heart receiving at least 30 Gy (V(30)) was (14.21±12.28)%. The maximum dose of exposure in spinal cord was (39.65±8.13) Gy. The incidence of radiation pneumonia and radiation esophagitis were 14.80%(29/196) and 65.82%(129/196), respectively. The adverse events were mostly grade 1-2, without grade 4 toxicity. Median overall survival (OS) and progression-free survival (PFS) were 70.1 months and 62.3 months, respectively. The 1-, 3- and 5-year OS rates of all patients were 75.1%、57.4% and 53.2%, respectively. The 1-, 3- and 5-year PFS rates were 75.1%、57.4% and 53.2%, respectively. Multivariate analysis demonstrated that patients'age (HR=1.023, P=0.038) and tumor diameter (HR=1.243, P=0.028)were the independent prognostic factors for OS, while tumor volume were the independent prognostic factor for PFS. Conclusions: Definitive radiotherapy is a promising therapeutic method in patients with T1-2N0M0 ESCC. Patients' age, tumor diameter and tumor volume may impact patients' prognosis.

Effects of incubation and chick rearing on intestinal morphology, digestive enzyme activities, and mRNA expression of nutrient transporter genes in the pigeon (Columba livia) under artificial farming conditions

The present study investigated the changes in morphology, enzyme activities in the pancreas and mucosa, and nutrient transporter gene expression in the duodenum and jejunum in male and female pigeons during the incubation and chick-rearing periods. Forty-two pairs of White King pigeons with 2 fertile eggs per pair were randomly divided into 7 groups by different breeding stages. The crypt depth of the duodenum and jejunum reached the peak at day 1 (R1) and day 7 (R7) of chick rearing, respectively. The jejunum surface area increased to a maximum value at R1. Amylase activity in the pancreas decreased to the lowest value at R1, whereas trypsin and lipase activities peaked at 17 D of incubation (I17) and R7, respectively. In male pigeons, mucosal Na⁺-K⁺-ATPase activity in the duodenum and jejunum was the highest at R15 and it was at I17 in female pigeons. Jejunum sucrose activity in female pigeons was higher at I4 than that at I17 (P < 0.05). The gene expression of FAT/CD36 and I-FABP in the duodenum gradually increased and then declined in the late chick-rearing period. SGLT1 in the jejunum decreased to a lower level at I17 and R25 in male pigeons (P < 0.05). GLUT2 expression in female duodenum and male jejunum decreased to a lower value at I17 compared with that at R15 (P < 0.05). In the late of incubation (from I10 to I17), expression of duodenum CAT1, B⁰AT1, and PepT1 and jejunum CAT1, ASCT1, and PepT1 in female pigeons was significantly reduced (P < 0.05), whereas opposite results were found in male jejunum CAT1 and duodenum ASCT1. In conclusion, variations of intestinal morphology, activities of pancreatic and mucosal enzymes, and gene expression of nutrient transporters during incubation and chick-rearing periods, underlying potential changes of digestive and absorptive function and intestinal adaptation with sexual effects, may represent a complicated response to stimuli of different breeding stages.

The profiling of amino acids in crop milk and plasma and mRNA abundance of amino acid transporters and enzymes related to amino acid synthesis in the crop tissue of male and female pigeons during incubation and chick-rearing periods

The present study was carried out to investigate the changes in amino acid (AA) contents of crop milk and plasma and mRNA abundance of AA transporters and AA synthesis-related enzymes in the crop tissue of male and female pigeons during incubation and chick-rearing periods. Forty-two pairs of adult White King pigeons with 2 fertile eggs per pair were randomly divided into 7 groups by different breeding stages. The AA content of crop milk decreased from day 1 (R1) to day 25 (R25) of chick rearing (P < 0.05). In both male and female adult pigeons, the contents of Thr, Leu, Val, His, Asp, and Pro in plasma increased to maximum levels on R25. Parental sex effect and interaction between stage and sex were observed in the AA contents of pigeon plasma (P < 0.05). For AA transporters, the mRNA abundances of SNAT2, ASCT1, LAT1, and y+LAT2 in the male crops reached the highest value on day 17 of incubation (I17), and the peak mRNA levels of PAT-1, xCT, b0,+AT, and CAT1 were found on R7 (P < 0.05). In females, the abundances of ASCT1, B0AT1, asc-1, and CAT1 mRNA peaked on R1, whereas the maximum levels of LAT1, PAT-1, b0,+AT, and y+LAT2 were observed on R7. For enzymes involved in AA synthesis, the highest gene expressions of glutamate dehydrogenase 1, acetolactate synthase in both parent pigeons, and L-threonine 3-dehydrogenase in female pigeon crops were attained on I17. The expressions of ornithine-δ-aminotransferase, glutamic-oxal(o)acetic transaminase 1, glutamic-oxal(o)acetic transaminase 2, asparagine synthetase, serine hydroxymethyltransferase 2, and glutamic-pyruvic transaminase 2 in both sexes and argininosuccinate lyase and L-threonine 3-dehydrogenase in males were the highest on R1. In conclusion, AA used for pigeon crop milk formation may originate from plasma and intracellular synthesis. The genes involved in AA transport and synthesis varied significantly with sexual effects, indicating that other factors should be considered in future explorations of the mechanism of protein formation in crop milk.

[Spatial-temporal cluster of hemorrhagic fever with renal syndrome in Hebei province, 2005-2016]

Objective: To explore the spatial-temporal distribution and epidemic characteristics of hemorrhagic fever with renal syndrome (HFRS) in Hebei province from 2005 to 2016. Methods: Records of HFRS cases reported from each county in Hebei during January 2005 to December 2016 were collected from National Notifiable Disease Surveillance System (NNDSS). Global and local spatial association statistics were used to measure the spatial autocorrelation and software GeoDa 1.2.0. Software SaTScan 9.4.1 was used to analyze spatiotemporal clusters. Software ArcGIS 10.2 was used to visualize the yearly scan results. Results: In Hebei province, a total of 8 437 human HFRS cases reported from 170 counties with an annual incidence rate of 0.99/100 000 population during 2005-2016. The peak incidence season was spring. Global spatial autocorrelation analysis on the incidence of HFRS at county-level showed that the value of Moran's I were all above 0 (P<0.05), indicating that the significant spatial cluster. The result of local indicators on spatial association (LISA) analysis revealed that identified hot spots were mainly in northeastern area, while cold spots were found in some counties of central and southern areas. Spatial-temporal scan detected that the primary cluster of HFRS incidence was mainly distributed in Qinhuangdao city and Tangshan city, including 11 counties (city/district): Beidaihe district, Haigang district, Funing district, Shanhaiguan district, Changli county, Lulong county and Qinglong Manchu autonomous county in Qinhuangdao city, and Qian'an city, Laoting county, Luanzhou city and Luannan county in Tangshan city (RR=39.64, P<0.001), during January-July in 2005. Conclusions: There were significant spatial-temporal cluster of HFRS in Hebei from 2005 to 2016. The cluster areas of HFRS were mainly in northeastern Hebei, it is necessary to strengthen the prevention and control programs of HFRS in these areas.

Oral immunization with a Lactobacillus casei-based anti-porcine epidemic diarrhoea virus (PEDV) vaccine expressing microfold cell-targeting peptide Co1 fused with the COE antigen of PEDV

AIMS

The aims of this study were to develop an effective M cell-targeting oral vaccine, involving Lactobacillus casei to deliver the porcine epidemic diarrhoea virus (PEDV) core neutralizing epitope (COE) antigen conjugated with M cell-targeting peptide Co1 as an adjuvant, against PEDV infection.

METHODS AND RESULTS

Genetically engineered L. casei 393 (L393) strains expressing PEDV COE antigen only (pPG-COE/L393) or fused-expressing COE and M cell-targeting peptide Co1 (pPG-COE-Co1/L393) were constructed, and the immunogenicity upon administration as an oral vaccine was evaluated. The results showed that higher anti-PEDV serum IgG and mucosal SIgA antibody responses were induced in mice orally immunized with strain pPG-COE-Co1/L393 as compared to the mice immunized with strain L393 expressing COE alone or carrying the empty plasmid. In addition, the use of the Co1 ligand elicited a splenocyte proliferative response more effectively in comparison with the COE antigen alone and supported a skewed T helper 2 type of immune response against PEDV.

CONCLUSIONS

pPG-COE-Co1/L393 can effectively induce mucosal, humoural and Th2-type cellular immune responses against PEDV infection via oral administration. Furthermore, M cell-targeting peptide ligand Co1 is a good mucosal adjuvant.

SIGNIFICANCE AND IMPACT OF THE STUDY

Lactobacillus casei delivering the COE antigen of PEDV conjugated with a M cell-targeting peptide Co1 as an immune adjuvant is a promising oral vaccine candidate for PEDV.

Relationship between circadian blood pressure variability and function of islet α and β cell in type 2 diabetes with dyssomnia

AIMS

To investigate the relationship between circadian blood pressure (BP) variability and function of islet α and β cell in type 2 diabetes (T2D) with dyssomnia.

METHODS

Patients with T2D were divided into dyssomnia group and non-dyssomnia group by PSQI. OGTT, insulin and glucagon-releasing test were tested, and ambulatory BP was monitored for 24 hours to compare two groups with α and β cell, circadian BP variability and fasting and post-meal BP variability. The correlation and regression analysis were made between PSQI and other indicators.

RESULTS

In dyssomnia group, ① Glucagon, glucagon/insulin ratio and AUCG were significantly higher (P < 0.05). ② Fasting insulin (13.32 ± 4.54 mIU/L), AUCI (8.51 ± 0.54) and HOMA-IR (4.62 ± 1.11) were high (P < 0.05). But ISI (-4.27 ± 0.77) was low (P < 0.05). ③ Mean 24-hour and nighttime SBP and DBP, as well as their standard deviations and coefficients of variation, were all higher in the dyssomnia group (P < 0.05). Multiple stepwise regression analysis showed that PSQI score was positively related to AUCG, HOMA-IR, nighttime SBP, and negatively related to ISI and nocturnal BP fall (P < 0.05).

CONCLUSION

Dyssomnia may cause abnormal circadian BP variability through various mechanisms. Improving dyssomnia can help to better function the islet α and β cell and restore normal circadian BP variability.

Atmospheric organic nitrogen deposition: analysis of nationwide data and a case study in Northeast China

The origin of atmospheric dissolved organic nitrogen (DON) deposition is not very clear at present. Across China, the DON deposition was substantially larger than that of world and Europe, and we found significant positive correlation between contribution of DON and the deposition flux with pristine site data lying in outlier, possibly reflecting the acute air quality problems in China. For a case study in Northeast China, we revealed the deposited DON was mainly derived from intensive agricultural activities rather than the natural sources by analyzing the compiled dataset across China and correlating DON flux with NH4(+)-N and NO3(-)-N. Crop pollens and combustion of fossil fuels for heating probably contributed to summer and autumn DON flux respectively. Overall, in Northeast China, DON deposition could exert important roles in agro-ecosystem nutrient management and carbon sequestration of natural ecosystems; nationally, it was suggested to found rational network for monitoring DON deposition.

Alteration of the intestinal barrier and GLP2 secretion in Berberine-treated type 2 diabetic rats

For centuries, Berberine has been used in the treatment of enteritis in China, and it is also known to have anti-hyperglycemic effects in type 2 diabetic patients. However, as Berberine is insoluble and rarely absorbed in gastrointestinal tract, the mechanism by which it works is unclear. We hypothesized that it may act locally by ameliorating intestinal barrier abnormalities and endotoxemia. A high-fat diet combined with low-dose streptozotocin was used to induce type 2 diabetes in male Sprague Dawley rats. Berberine (100 mg/kg) was administered by lavage to diabetic rats for 2 weeks and saline was given to controls. Hyperinsulinemia and insulin resistance improved in the Berberine group, although there was no significant decrease in blood glucose. Berberine treatment also led to a notable restoration of intestinal villi/mucosa structure and less infiltration of inflammatory cells, along with a decrease in plasma lipopolysaccharide (LPS) level. Tight junction protein zonula occludens 1 (ZO1) was also decreased in diabetic rats but was restored by Berberine treatment. Glutamine-induced glucagon-like peptide 2 (GLP2) secretion from ileal tissue decreased dramatically in the diabetic group but was restored by Berberine treatment. Fasting insulin, insulin resistance index, plasma LPS level, and ZO1 expression were significantly correlated with GLP2 level. In type 2 diabetic rats, Berberine treatment not only augments GLP2 secretion and improves diabetes but is also effective in repairing the damaged intestinal mucosa, restoring intestinal permeability, and improving endotoxemia. Whether these effects are mechanistically related will require further studies, but they certainly support the hypothesis that Berberine acts via modulation of intestinal function.

Human insulin from a precursor overexpressed in the methylotrophic yeast Pichia pastoris and a simple procedure for purifying the expression product

The methylotrophic yeast Pichia pastoris, which proved successful in producing many heterologous proteins, was used to express an insulin precursor. A transformant with a high copy number of the gene integrated into the chromosome was obtained by the dot-blotting method. In high-density fermentation using a simple culture medium composed mainly of salt and methanol, the expression level reached 1.5 g/L. A simple two-step method was established to purify the expression product from the culture medium with an overall recovery of about 80%. After tryptic transpeptidation, human insulin with full receptor binding capacity and biological activity was obtained. In the presence of zinc, the recombinant human insulin could be crystallized in the rhombohedral form.

[Effect of fuzheng kangbai granule on immune function and survival time in minimal residual leukemia model in mice]

OBJECTIVE

To observe the effects of Fuzheng Kangbai Granule (FZKBG) on immune function and survival time in minimal residual leukemia (MRL) model mice and study its mechanism.

METHODS

MRL model mice were established by hypodermic inoculation with L7212 cells following intraperitoneal injection of cytoxan (CTX) 25 mg/kg 3 days later, and divided into the control group and FZKBG group. The changes of T-lymphocyte subsets, including CD3+, CD4+ and CD8+, and the survival time in model mice were observed.

RESULTS

Comparing with the control group, FZKBG could obviously increase both the percentage and absolute value of CD3+ and CD4+ lymphocytes and prolong the survival time of model mice, the prolongation rate being 29.6%-60.4%.

CONCLUSION

FZKBG could markedly prolong the survival time of MRL mice, its mechanism might be through elevating the immune function and inhibiting the leukemic cells in model mice.

[Effects of long-term physical training on age-related changes of energy transformation of mice heart mitochondria]

AIM AND METHODS

To observe effects of long-term physical training (running wheel) on the age-related changes of energy transformation of mice heart mitochondria.

RESULTS

RCR and ADP/O decreased with age in the presence of a-ketoglutaric acid, especially in the late of age, which indicated that oxidative phosphorylation coupling decreased in the aging process.

CONCLUSION

Adaptive changes of mitochondria were brought by long-term physical training which might delay the age-related decline of mitochondrial function.

Binding characteristics of pancreatic polypeptide receptors on rat hepatic membranes

AIM

To study the binding characteristics of pancreatic polypeptide (PP) receptors on rat hepatic membranes.

METHODS

125I-PP suitable to study interaction between ligand and receptors were prepared. 125I-porcine PP and 125I-duck PP were used to study PP receptor binding in the controlled conditions.

RESULTS

The binding of 125I-porcine PP to receptors on rat hepatic membranes was time- and temperature-dependent. The specific binding of 125I-porcine PP was inhibited by unlabeled porcine PP in a concentration-dependent manner, whereas duck PP was only partially inhibited in the high concentration (> 500 nmol.L-1). Scatchard analysis produced a curvilinear plot, suggesting multiple affinity binding sites, i.e., high-affinity and low-affinity with dissociation constants (Kd) 5.4 and 158 nmol.L-1, respectively.

CONCLUSION

Rat hepatic membranes possessed specific PP receptors and porcine PP binding activity was much higher than that of duck PP.

Frequent ras gene mutations in squamous cell cervical cancer

Eighty samples of cervical invasive squamous cell carcinoma were examined for ras gene mutations using polymerase chain reaction (PCR) followed by restriction enzyme digestion. We found 28 (35%) cervical cancers contained ras mutations at H-ras codon 12, 49 (61%) at K-ras codon 12, and 5 (6%) at K-ras codon 13. There were no significant differences in incidence of the ras gene mutations among different histologic grades or clinical stages of the cancer (P > 0.05). This result suggests that ras mutation may be an important step involved in a substantial number of cervical carcinoma. The interaction of ras with other genes and/or events may also be involved in pathogenesis of this malignancy.

[Protective effects of nicorandil on action potentials in anoxia and reoxygenated ventricular myocardium of guinea pig]

Standard microelectrode techniques were used to study the effects of nicorandil (500 mumol.L-1) on action potentials in anoxia and reoxygenated ventricular myocardium of guinea pig. The main results: (a) Nicorandil shortened the action potentials duration (APD) and increased the ratio of effective refractory period (ERP) to APD90 (ERP/APD90). It did not cause significant changes in resting potential (RP), the maximal rate of rise of phase 0 (Vmax) and action potential amplitude (APA); (b) Exposure of the preparation to anoxic conditions (hypoxia, acidosis, glucose deprivation, and hyperkalemia) for 20 min, resulted in a marked depolarization of RP, a shortening of APD, reductions of APA and Vmax, and an increase in the ratio of ERP/APD90; (c) Nicorandil did not produce any additional effect on these parameters during anoxia except aggravated shortening of APD; (d) The changes of action potential parameters during anoxia were all completely reversed when the preparation was reoxygenated in the absence of the drug for 20 min. In the presence of the drug, however, APD was only partially reversed; (e) Nicorandil decreased the incidence of abnormal automaticity occurring during reoxygenation from 14/16 to 4/16. It is concluded that nicorandil antagonizes the cellular mechanisms which underlie the reoxygenation arrhythmias and prevent the reoxygenation-induced arrhythmias.

Detection of ZC rosette-forming lymphocytes in the healthy aged with Taichiquan (88 style) exercise

Taking the percentage of zymosan-complement complex rosette forming cells (ZC-RFC%) and the number of zymosan-complement Complex rosette forming cells (ZC-RFC) in the peripheral blood as indices of humoral immunity, bone marrow derived lymphocytes were detected by modified Sondra B cell assay in 24 healthy aged taking part in Taichiquan (88 style) exercise and 24 age-matched normal subjects without any physical training. At rest, the ZC-RFC% of the exercise group was lower than that of the controls; immediately following a set of Taichiquan exercise, the increments of ZC-RFC% and ZC-RFC were highly significant. These findings give evidence of humoral immunity which supports the viewpoint that Taichiquan exercise can induce enhancement of cellular immunity in the aged.

Effect of ballet on immunity in young people

The peripheral blood samples obtained from 32 ballet students with a mean age of 17.5 years and 32 age-matched non- dancers who comprised a control group were analysed using the microdeterminations of lymphocyte blast transformation and mixture rosette forming cells. The percentage of lymphocyte blast transformation of ballet students was normal, but their percentage of E-rosette forming cells was lower than that of controls at rest. A significant increase in the percentage of zymosan-complement rosette forming cells was seen during dancing. The study suggests that a saving effect on expenditure of cellular immunofunction is exhibited in ballet students at rest and that intensive ballet-exercise induces an immediate humoral immune response change. However, the effect needs to be dynamically observed and the clinical implication of the response change remains to be proved.

Isolation and sequence determination of goose pancreatic polypeptide

Goose pancreatic polypeptide was isolated in crystalline form from goose pancreas. Its amino acid sequence was determined by Edman degradation and compared with avian pancreatic polypeptide.