[Net survival analysis of cancer in Zhongshan City of Guangdong Province in China, 1970 to 2014]

Objective: To analyze survival data of cancer from 1970 to 2014 in Zhongshan City, Guangdong Province, and provide scientific basis for cancer prevention and control in Zhongshan City. Methods: The tumor incidence data of Zhongshan City, Guangdong Province from 1970 to 2014 were collected from Zhongshan Cancer Registry, and all patients were followed up to December 31, 2019. The standardized 5-year net survival rates and their annual percentage change (APC) and average annual percentage change (AAPC) for total and major cancers at different times were used to describe statistical analysis. The standardized survival rates were weighted using the International Cancer Survival Standard Age Coefficients. Results: There were 78 854 cancer patients eligible for the study in Zhongshan City of Guangdong Province from 1970 to 2014, among which lung cancer (13 466 cases, 17.08%), nasopharyngeal cancer (9715 cases, 12.32%) and liver cancer (9707 cases, 12.31%) were the main types of cancer. The morphology verification was 69.87% in the whole of cancers and the ranges were 21.07% to 97.00% in major cancers. From 2010 to 2014, the 5-year age-standardized net survival rates of cancers for all, males and females in Zhongshan City were 39.74%, 30.92% and 52.47%, in which were 97.98% for thyroid cancer, 74.29% for brain and central nervous system tumors, 73.92% for nasopharyngeal cancer, 50.23% for colorectal cancer, 81.38% for female breast cancer, 78.81% for uterine body cancer, 68.57% for cervical cancer, 49.33% for prostate cancer, 16.19% for lung cancer , 12.14% for liver cancer, and 11.78% for esophageal cancer, respectively. The survival rates of all cancers in Zhongshan City showed an increasing trends in 1970-2014 (AAPC=1.5%, P=0.025), and it was higher in female cancers than that of male in all periods. Conclusion: The standardized 5-year net survival rates of all and major cancers in Zhongshan City of Guangdong Province show an increasing trend from 1970 to 2014, but they are still at a medium-low levels compared with the countries and regions participating in CONCORD-3 project, suggesting that Zhongshan should continue to strengthen cancer prevention and control.

[Influence factors of poor efficacy after flap repair operation in patients with pressure ulcers]

Objective: To investigate the influence factors of poor efficacy after flap repair operation in patients with pressure ulcers. Methods: The retrospective case series study was conducted. From January 2011 to June 2021, 125 patients with stage Ⅲ and Ⅳ pressure ulcers treated in Hainan General Hospital met the inclusion criteria. There were 82 males and 43 females, aged 15-90 (57±20) years. According to the postoperative effects, the patients were divided into poor efficacy group (47 cases) and good efficacy group (78 cases). The clinical data of patients in the two groups were collected, including the age, gender, location, stage, size, and bone exposure of pressure ulcers, preoperative microorganism culture results of wound exudate sample, whether combined with osteomyelitis, diabetes, lower limb paroxysmal myospasm, and gatism or not, the number of surgical debridement combined with negative-pressure wound therapy, type of surgical flap, postoperative position, and preoperative albumin, leukocyte, C-reactive protein (CRP), and hemoglobin. Data were statistically analyzed with independent sample t test, Mann-Whitney U test, and chi-square test. The binary multivariate logistic regression analysis was conducted to screen the independent risk factors influencing the poor efficacy after flap repair operation in 125 patients with stage Ⅲ and Ⅳ pressure ulcers. Results: The ratio of patients with lower limb paroxysmal myospasm in poor efficacy group was 22/47, which was significantly higher than 3/78 in good efficacy group (χ2=33.83, P<0.01). The preoperative hemoglobin level of patients in poor efficacy group was (102±17) g/L, which was significantly lower than (113±20) g/L in good efficacy group (t=-3.24, P<0.01). The preoperative CRP level of patients was 39.1 (14.1, 91.6) mg/L in poor efficacy group, which was significantly higher than 15.3 (6.6, 42.0) mg/L in good efficacy group (Z=-3.04, P<0.01). There were no statistically significant differences in other indexes between patients in the two groups (P>0.05). Multivariate logistic regression analysis showed that age, lower limb paroxysmal myospasm, and preoperative hemoglobin level were the independent risk factors for poor efficacy after flap repair operation in patients with pressure ulcers (with odds ratios of 1.03, 40.69, and 0.97, 95% confidence intervals of 1.00-1.06, 9.18-180.39, and 0.95-1.00, respectively, P<0.05 or P<0.01). Conclusions: Poor efficacy after flap repair operation in patients with pressure ulcers is affected by many factors, among which the age, lower limb paroxysmal myospasm, and preoperative hemoglobin level are the independent risk factors.

[Research advances on stem cell therapy for diabetic foot wounds]

Diabetic foot wound repair is a challenging issue in clinical practice. Due to the influence of multiple factors including the damage and regeneration failure of local tissue, the impaired pathways of wound repairing through blood vessels and nerve nutrition, and disorders of a variety of cellular factors, traditional treatment methods are often difficult to achieve good therapeutic effects. Stem cells are a type of cells with potentials of multidirectional differentiation, which also possess functions such as regulating immunity and paracrine to facilitate the comprehensive wound repair, so they have promising application prospect at present for the treatment of diabetic foot wounds. Because the relevant parameters of stem cell treatment are in the exploratory phase, there were no standardized data. This paper reviews the application of stem cells in the research of diabetic foot wound treatment over the past 6 years, analyzing and summarizing the contents in focused aspects including the types and sources of stem cells, effects of donor age and gender on stem cells, mode of administration, transplantation survival rate and safety, which may provide a reference for further application of stem cells in the clinical treatment of diabetic foot wound.

[Incidence and mortality of laryngeal cancer in China, 2014]

Objective: To estimate the incidence and mortality of laryngeal cancer in China based on the cancer registration data in 2014, collected by the National Central Cancer Registry (NCCR), and to provide support data for the control and prevention of laryngeal cancer. Methods: The incident and death data of laryngeal cancer in 2014 from 339 cancer registries met the quality criteria of NCCR, and then adopted for analysis. The incident and death number, crude rate, age standardized rate, truncated rate and proportion which stratified by areas (urban/rural) and age were calculated. The nationwide incidence and mortality of laryngeal cancer in 2014 were estimated by combining with those data on national population in 2014. Chinese population census in 2000 and Segi's population were used for age-standardized incidence/mortality rates. Results: It was estimates that 23.4 thousand new cases of laryngeal cancer occurred in China in 2014. There were 20.8 thousand males and 2.6 thousand females. And 14.5 thousand occurred in urban areas, while 8.9 thousand in rural areas. The age standardized rates of incidence by world standard population (ASRs world) in male, female and both genders were 2.05/100, 000, 0.24/100, 000 and 1.14/100, 000, respectively, whereas those were 1.22/100, 000 and 1.03/100, 000 for urban and rural areas. The incidence was much higher in males than females, and slightly higher in urban areas than those in rural areas. Moreover, it was estimates that 13.2 thousand death cases of laryngeal cancer occurred in China in 2014. There were 11.5 thousand males and 1.7 thousand females. And 7.8 thousand occurred in urban areas, while 5.4 thousand in rural areas. The age standardized rates of mortality by ASRs world in male, female and both genders were 1.08/100, 000, 0.14/100, 000 and 0.60/100, 000, respectively, whereas those were 0.60/100, 000 and 0.59/100, 000 for urban and rural areas. The mortality was much higher in males than females, and slightly higher in urban areas than those in rural areas. In males, the age specific incidence and mortality of laryngeal cancer increased greatly from 40-44 and 45-44 years old, respectively, and peaked at age group of 75-79 and >85 years old. In females, the age specific incidence and mortality increased slowly from 50-54 and 60-64 years old, respectively, and peaked at age group of 80-84 and >85 years old. The trends remained similar in urban and rural areas, except for the different peak ages. Conclusions: The incidence and mortality of laryngeal cancer in China are at middle-low levels worldwide, and there are obvious differences between urban and rural areas with distinct gender disparity. Comprehensive prevention and control strategies should be carried out according to local status and age groups.

SNP analysis reveals estrogen receptor 1 (<i>ESR1</i>) gene variants associated with laying traits in quails

Abstract. In this study, the estrogen receptor 1 (ESR1) gene was studied as a candidate gene for laying traits of two quail populations (the yellow-feather quail and chestnut-feather quail). Five pairs of primers were designed to detect single-nucleotide polymorphisms (SNPs) of exon 1, 2, 4, 8 and intron 1 of the ESR1 gene by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) and sequencing methods. Only the products amplified from exon 8 displayed polymorphism. The results showed one novel variation: a variation in exon 8 of ESR1 gene (g.91C > T, KC977991 and KC977992). It was associated with some laying traits in two quail populations including egg weight, the age of first egg and egg number at 20 weeks. And the CC genotype was associated with superior egg number at 20 weeks. Therefore, we speculated that the variation in exon 8 of ESR1 gene may have an effect on laying traits in the abovementioned quail populations.

Two novel linkage SNPs of VLDLR gene intron 11 are associated with laying traits in two quail populations

Abstract. The very low density lipoprotein receptor (VLDLR) is an important multifunctional receptor and plays a key role in chicken reproduction. This study is designed to investigate the effect of variants in the VLDLR gene on quail laying traits. Two quail populations were studied – yellow feather quail and chestnut feather quail; 384 individuals per breed were used. The laying traits (the weight of the first egg, the age of the first egg, egg weight, the weight of 20-week-old and the egg number of 20-week-old) were measured and recorded. The polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) method was developed to genotype those individuals. The results showed two novel polymorphisms, i.e. two linkage variations in intron 11 of the VLDLR gene (363T > C and 392C > T). They are associated with the weight of the first egg, the age of the first egg and egg number of 20-week-old in yellow feather and chestnut feather quail. The two variations in intron 11 of VLDLR may be linked with potential major loci or genes affecting some laying traits.

A comparative study of the retention or removal of jejunal mucosa during pancreatic duct to jejunal anastomosis

AIM

The aim of this study was to compare the two anastomosis methods, that is, the retention or the removal of the jejunal mucosa during pancreatic duct to jejunal anastomosis after pancreaticoduodenectomy (PD).

METHODS

For this purpose, 46 PD patients were randomly and equally divided into groups A and B. In group A, the remnant pancreas was inserted 3 cm into the jejunum and the connecting part was sutured. In group B, the jejunal mucous membrane was cauterized 3 cm at the end, the remnant pancreas was sutured with the jejunal muscle layer, and the jejunum and pancreas were sutured together.

RESULTS

We found that in group A, the reoperation rate due to delayed bleeding was 13% (3/23) and the ulcer bleeding around anastomosis was 4.3% (1/23). In group B, the reoperation rate due to bleeding was 4.3% (1/23) and the incidence of postoperative pancreatic fistula was 17.4% (4/23). The duration of pancreaticojejunostomy operation in group A (46 ± 0.34 min) was shorter than in group B (P<0.001).

CONCLUSION

We, therefore, concluded that the pancreatic duct to jejunal anastomosis with retained jejunal mucosa was a simple and easy to perform method while it also excluded the risk of postoperative pancreatic fistula formation.

An SNP in the MyoD1 gene intron 2 associated with growth and carcass traits in three duck populations

Myogenic differentiation 1 (MyoD1) genes belong to the MyoD gene family and play key roles in growth and muscle development. This study was designed to investigate the effects of variants in the MyoD1 gene on duck growth and carcass traits. Three duck populations (Cherry Valley, Jingjiang, and Muscovy) were sampled, their growth and carcass traits were measured, and they were genotyped using the PCR-RFLP method. The results showed one novel polymorphism, an alteration in intron 2 of the MyoD1 gene (A to T). It was associated with the traits of weight at 8 weeks, carcass weight, breast muscle weight, leg muscle weight, eviscerated percentage, percentage of leg muscle weight, dressing percentage, and lean meat percentage. This alteration in intron 2 of MyoD1 may be linked with potential major loci or genes affecting some growth and carcass traits.

One novel SNP of growth hormone gene and its associations with growth and carcass traits in ducks

In this study, the growth hormone (GH) gene was studied as a candidate gene for growth and carcass traits of three duck populations (Cherry Valley duck, Muscovy duck and Jingjiang duck). Three pairs of primers were designed to detect single nucleotide polymorphisms of introns 2, 3 and 4 of the GH gene by polymerase chain reaction-restriction fragment length polymorphism and sequencing methods. Only the products amplified from intron 2 displayed polymorphism. The results showed one novel polymorphism: a variation in intron 2 of GH gene (C172T, JN408701 and JN408702). It was associated with some growth and carcass traits in three duck populations including birth weight, 8-week weight, carcass weight, breast muscle weight, leg muscle weight, eviscerated weight, lean meat rate, dressing percentage, etc. And the TT and CT genotypes were associated with superior growth and carcass traits in carcass weight, dressing percentage and percentage of eviscerated weight. Therefore, the variation in intron 2 of GH may be a molecular marker for superior growth and carcass traits in above duck populations.

Pineal parenchymal tumours: minimum apparent diffusion coefficient in prediction of tumour grading

Retrospective assessment was performed of the minimum apparent diffusion coefficient (minADC) together with quantitative assessment of the histopathological features of resected tumour tissue and the Ki-67 labelling index (LI) for predicting pineal parenchymal tumour (PPT) grade. Magnetic resonance images of tumours from 26 male and female patients (mean age 27.7 years) with pathologically confirmed PPTs, comprising 10 pineocytomas (PCs), seven pineal parenchymal tumours of intermediate differentiation (PPTIDs) and nine pineoblastomas (PBs), were reviewed retrospectively. Using ADC maps derived from isotropic diffusion-weighted images, the minADC value of each tumour was determined postoperatively from several regions of interest defined in the tumour, excluding cystic, necrotic, haemorrhagic or calcified components. Surgical intervention was undertaken in all cases. The Ki-67 LI was measured in surgical specimens. Mean minADC and Ki-67 LI showed significant differences among PCs, PPTIDs and PBs, and minADC was negatively correlated with Ki-67 LI. It is concluded that the minADC of PPTs provide useful additional information when predicting tumour grading.

Monitoring release of ketoprofen enantiomers from biodegradable poly(d,l-lactide-co-glycolide) injectable implants

A stereoselective reversed-phase HPLC assay was developed that could simultaneously quantify S-(+) and R-(-) enantiomers of ketoprofen in release samples. Racemic ketoprofen (rac-KET) and its S-(+) enantiomer (S-(+)-KET) were dissolved in an injectable viscous polymer solution consisting of the biodegradable poly(D,L-lactide-co-glycolide, 70:30) (D,L-PLG) and a solvent, N-methyl-2-pyrrolidone (NMP). Once injected into an aqueous environment, the polymeric mixture solidified into a solid implant due to the leaching of NMP. In vitro release studies show that such implants with ketoprofen can provide sustained release of the drug lasting about three months in a pH 7.4 release medium. Moreover, a preferential faster S-(+)-KET release over R-(-)-KET was observed for the implants containing 4%, 7%, and 10% of racemic ketoprofen in the neutral pH 7.4 release medium. Stereoselective release was minimal in the first 42 days in vitro but became very pronounced at later time points. When S-(+)-KET was incorporated into the polymeric mixture, its release was also faster than that of the racemic ketoprofen, confirming the stereoselective release of ketoprofen from the d,l-PLG implants. The observed stereoselective release of KET at pH 7.4 was most likely produced by chiral interactions between KET enantiomers and transiently produced D-lactic acid or L-lactic acid rich domains within the implants during D,L-PLG degradation. However, such stereoselective release was not observed in pH 10.0 release medium, probably due to a much faster and homogeneous polymer degradation. The study suggests possible stereoselective release of racemic drugs from D,L-PLG microspheres and implants in vivo.

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.

Four new monomeric insulins obtained by alanine scanning the dimer-forming surface of the insulin molecule

The residues A21Asn, B12Val, B16Tyr, B24Phe, B25Phe, B26Tyr and B27Thr, buried in the dimer of insulin, were identified by means of alanine-scanning mutagenesis. The receptor binding activity, in vivo biological potency and self-association properties of the seven single alanine human insulin mutants were determined. Four of the seven single alanine mutants, [B12Ala]human insulin, [B16Ala]human insulin, [B24Ala]human insulin and [B26Ala]human insulin, are monomeric insulin, which indicates that B12Val, B16Tyr, B24Phe and B26Tyr are crucial for the formation of insulin dimer. The monomeric [B16Ala]human insulin and [B26Ala]human insulin retain 27 and 54% receptor binding activity, respectively, and nearly the same in vivo biological potency compared with native insulin, so they could be developed as the fast-acting insulin.

Delayed radiation encephalopathy after radiotherapy for nasopharyngeal cancer: a CT study of 45 cases

The CT features of 45 cases of delayed radiation encephalopathy (including radiation necrosis) following radiotherapy for nasopharyngeal carcinoma are reported. The brain lesions were uni- or bilateral and involved mainly the white matter and subsequently the gray matter of the lower portion of the brain included within the portals of irradiation and its vicinity. The lesions were edematous and hypodense on CT and showed postcontrast enhancement in 50% of the cases. Within the period of follow-up (1-5 years), the lesions showed remissions and exacerbations and in some cases stabilized. In addition, there was progressive cerebral atrophy, manifesting itself mainly as dilatation of the temporal horns, the neighboring cisterns, and sylvian fissures. In some cases that were followed for a long time, the cerebral lesions showed either foci of calcification or encephalomalacia and/or porencephaly.

Synthesis of the leu-enkephalin gene

The synthesis of Leu-enkephalin gene by an alternative approach was described in this paper. The sequence of the synthetic gene, 26 base-pairs in length, was derived from the amino acid sequence of the hormone peptide Leu-enkephalin. It bears single-stranded cohesive termini for the restriction endonucleases EcoR I and BamH I so that it may be inserted into a pBR 322 plasmid. The 4 deoxyoligonucleotide fragments, varying in length from octanucleotide to octadecanucleotide, were synthesized by an improved phosphotriester method developed in our laboratory. All chemically synthetic fragments were pure and had the correct sequences. The assembly of the Leu-enkephalin gene was carried out in a one-step ligation reaction catalysed by T4-DNA ligase with good yield. Finally, the purified products from polyacrylamide gel electrophoresis had the correct joining-points as predicted.

The cloning and expression of the synthetic leu-enkephalin gene in E. coli

The synthetic leu-enkephalin (LEK) gene was joined with pBR322 and transformed to E. coli. The recombinant plasmids containing the LEK gene were selected by colony hybridization, and characterized by restriction mapping and Southern's technique. The lac operon was used to control the expression of the LEK gene. A recombinant plasmid, pEL 103, in which the lac operon and LEK gene are transcribed in the same direction, produces LEK in E. coli. The level of LEK detected by radioimmunoassay reaches 426 ng per mg of bacterial protein.

Total synthesis of yeast alanine transfer ribonucleic acid

By a combination of chemical and enzymatic methods, small oligonucleotides with lengths varying from 2 to 8 nucleotides were synthesized from mononucleotides. The small oligonucleotides were then ligated with T4 RNA ligase into six large oligonucleotides (9 to 19 nucleotides long) which were further ligated to form two half molecules with 35 and 41 nucleotides respectively. Finally, the two synthetic half molecules were annealed and ligated to obtain the whole molecule of yeast alanine tRNA (tRNAAlay). Prior to this, two semi-syntheses were performed, i.e. ligation of the synthetic 5'-half molecule with the natural 3'-half molecule and that of the natural 5'-half molecule with the synthetic 3'-half molecule. Both the semi-synthetic tRNAAlay and the synthetic tRNAAlay occupy the same position as the natural tRNAAlay after electrophoresis on a 20% polyacrylamide gel. They have the same chemical composition (containing 9 modified nucleotides of 7 different species) and structure as the natural tRNAAlay and are biologically active, i.e. accepting and transferring alanine into proteins in a cell-free protein synthesizing system, the accepting activity of the synthetic product is 52-66% of that of the natural tRNAAlay and 91-106% of that of the reconstituted product of the two natural half molecules. The incorporation activity of alanine into proteins of the synthetic 3H-alanine tRNAAlay is 63%, corresponding to 91% of that of the natural tRNAAlay and 115% of that of the reconstituted product of the two natural half molecules. To the best of our knowledge, this is the first time that a natural RNA with biological activity is synthesized.

Synthesis of the 3'-half molecule of yeast alanine tRNA

This paper deals with the synthesis of the 3'-half molecule of yeast alanine transfer RNA (tRNAAlay) by ligation with T4 RNA ligase of three component oligonucleotide fragments corresponding to nucleotides 36-45(I), 46-57(II) and 58-76(III) in succession extending from the 3'-end to the 5'-end. First, in a ratio of acceptor to donor at 1.5 to 1, we adopted a method of three successive reactions, namely, the 5'-phosphorylation of the nonadecamer (III), ligation with the dodecamer (II) and the 5'-phosphorylation of the ligation product formed; with one isolation step and obtained the 5'-phosphorylated 31mer(46-76) (IV) in an overall yield of 70%. Then the 31mer(IV) as a donor was ligated with 3 times of decamer (I) to form the 41mer(36-76) (V), the 3'-half molecule of tRNAAlay. The yield was 67%. After 5'-phosphorylation, (V) was ligated with the natural 5'-half molecule to form the semi-synthetic tRNAAlay, which was biologically active, i.e. accepting and transferring (3H)-alanine into proteins.