[A prospective study of the effect and mechanism of autologous platelet-rich plasma combined with Meek microskin grafts in repairing the wounds of limbs in severely burned patients].

Objective: To observe the effect of autologous platelet-rich plasma (PRP) combined with Meek microskin grafts in repairing the wounds of limbs in severely burned patients, and to explore the mechanism. Methods: The prospective controlled research method was used. From September 2016 to January 2020, 16 patients aged 18-69 years, with extensive deep burns, including 9 males and 7 females, who met the selection criteria were admitted to the Department of Burns and Plastic Surgery of the 909th Hospital of the Joint Logistic Support Force of PLA. The bilateral limbs with similar injury in 8 patients were divided into Meek skin grafting+PRP group and Meek skin grafting alone group according to the random number table; in the other 8 patients, the limbs with severer injury were included in Meek skin grafting+PRP group, and the limbs on the other side were included in Meek skin grafting alone group. The wounds of affected limbs in the two groups were treated correspondingly. On post surgery day (PSD) 10, the survival and fusion of Meek microskin grafts were observed and the survival rate and fusion rate were calculated; the histological morphology and the angiogenesis of the basal tissue of Meek microskin graft were observed by hematoxylin-eosin staining and immunohistochemical staining, respectively, with the microvessels being counted. Data were statistically analyzed with paired sample t test. Results: On PSD 10, the wounds of affected limbs in Meek skin grafting+PRP group were dry, and most of the transplanted skin grafts were closely adhered to the basal tissue; while a small amount of exudate could be found in the wounds of affected limbs in Meek skin grafting alone group, and a small part of the transplanted microskin grafts fell off or poorly attached to the basal tissue. On PSD 10, the survival rate and the fusion rate of Meek microskin grafts in the wounds of affected limbs in Meek skin grafting+PRP group were (94±3)% and (86±4)%, which were significantly higher than (89±4)% and (79±4)% of Meek skin grafting alone group, respectively (t=3.633, 4.229, P<0.01). On PSD 10, the basal epidermis was closely connected with dermis of Meek microskin grafts in the wounds of affected limbs in Meek skin grafting+PRP group, with more inflammatory cell infiltration and active microvascular hyperplasia, while the basal epidermis was less closely connected with dermis of Meek microskin grafts in the wounds of affected limbs in Meek skin grafting alone group, with obvious degeneration of collagen fibers under the dermis, less inflammatory cell infiltration, and slightly poor microvascular hyperplasia. On PSD 10, the distribution of microvessels in basal tissue of Meek microskin grafts in the wounds of affected limbs in Meek skin grafting+PRP group were densely clustered, while the distribution of microvessels in Meek skin grafting alone group were scattered, sparse, and dotted. On PSD 10, the number of microvessels in basal tissue of Meek microskin grafts in the wounds of affected limbs in Meek skin grafting+PRP group was 36±6 in each 400-fold visual field, which was significantly more than 29±7 of Meek skin grafting alone group (t=2.671, P<0.05). Conclusions: Autologous PRP can effectively promote the survival rate and fusion rate of Meek microskin grafts in the wounds of limbs after escharectomy in severely burned patients by promoting angiogenesis at the base of Meek microskin grafts.

[Three-dimensional MRI reconstruction research on the anatomical relationship among uterosacral ligament and ureter or rectum in pelvic organ prolapse patients].

Objective: To study the anatomical relationship among uterosacral ligament and ureter or rectum by using MRI three-dimensional reconstruction model in pelvic organ prolapse (POP) patients. Methods: According to the research standard, 67 POP patients were enrolled, who accepted pelvic MRI before surgery in Nanfang Hospital, Southern Medical University during May 2015 to March 2020. Three-dimensional model of uterosacral ligament was reconstructed. The intersection point of the fitting curve of uterosacral ligament and ischial spine level marked point P0, every 1 cm increasing from P0 towards the sacrum marked points P1, P2, and P3. Distances were measured between rectum or ureter to uterosacral ligament respectively at the P0-P3 horizontal levels. Results: (1) The distances between the left ureter and the left uterosacral ligament were (15.45±7.46) to (19.31±11.38) mm, and the distances between the right ureter and the right uterosacral ligament were (13.77±8.16) to (14.78±9.18) mm. At the P1 horizontal level ureters were the closest to uterosacral ligaments, and the right ureter was the closest to right uterosacral ligament [(13.45±9.34) mm] at P2 horizontal level in severe POP group. The farthest distance presented at the P3 horizontal level between bilateral ureters and uterosacral ligaments. (2) At the P0 horizontal level, the rectum was the closest to the bilateral uterosacral ligaments [left: (20.62±9.99) mm, right: (16.82±9.63) mm; P=0.026], and the rectum was closer to the right uterosacral ligament. There were no significant differences in the distance between rectum and bilateral uterosacral ligaments in mild POP group (P>0.05), and the results of severe POP group also showed the rectum was closer to the right uterosacral ligament [(15.64±10.31) mm at P0 horizontal level]. Conclusions: Right ureter and rectum are closer to the right uterosacral ligament. Gynecologists should pay more attention to avoid damaging the right ureter and rectum during the operation of the right uterosacral ligament in POP patients.

Blocking the epithelial-to-mesenchymal transition pathway abrogates resistance to anti-folate chemotherapy in lung cancer.

Anticancer therapies currently used in the clinic often can neither eradicate the tumor nor prevent disease recurrence due to tumor resistance. In this study, we showed that chemoresistance to pemetrexed, a multi-target anti-folate (MTA) chemotherapeutic agent for non-small cell lung cancer (NSCLC), is associated with a stem cell-like phenotype characterized by an enriched stem cell gene signature, augmented aldehyde dehydrogenase activity and greater clonogenic potential. Mechanistically, chemoresistance to MTA requires activation of epithelial-to-mesenchymal transition (EMT) pathway in that an experimentally induced EMT per se promotes chemoresistance in NSCLC and inhibition of EMT signaling by kaempferol renders the otherwise chemoresistant cancer cells susceptible to MTA. Relevant to the clinical setting, human primary NSCLC cells with an elevated EMT signaling feature a significantly enhanced potential to resist MTA, whereas concomitant administration of kaempferol abrogates MTA chemoresistance, regardless of whether it is due to an intrinsic or induced activation of the EMT pathway. Collectively, our findings reveal that a bona fide activation of EMT pathway is required and sufficient for chemoresistance to MTA and that kaempferol potently regresses this chemotherapy refractory phenotype, highlighting the potential of EMT pathway inhibition to enhance chemotherapeutic response of lung cancer.

[Polymorphism and haplotype study of Y-chromosomal multi-STRs loci in Han population in Guangzhou].

Using polymerase chain reaction and silver stain, polymorphism and haplotype study of Y-chromosomal multi-STRs loci: DYS19, DYS389I/II, DYS390 were studied. 111 samples of male were collected from Guangzhou area. 5 alleles were determined in DYS19 locus, 4 alleles in DYS389I locus, 5 alleles in DYS389II locus and 5 alleles in DYS390 locus. Compared with other racial populations, differences of distribution of allele frequencies existed significantly. 72 haplotype were present in this study.

[PCR-based DNA analysis of vWA31A, TH01, F13A01, FESFPS, TPOX and CSF1PO].

The allele and genotype frequencies of 6 tetranucleotide STR loci were investigated in a sample of 132 unrelated individuals from Chinese Han population. The PCR products were analyzed on 6% denaturing PAGE and detected using fluorescently labeled primers in an automated 377 sequencer(PE). All loci meet Hardy-Weinberg equilibrium. There was no random association of alleles among the 6 loci. The allele frequencies were compared with other population databases. Except locus vWA31A, the observed heterozygosity at other 5 loci was significantly lower than that reported in Caucasian and Black population studies. The calculated DP = 0.99999, PE = 0.9708, pM = 1.059 x 10(-5). The allelic frequency data can be used in forensic identification and paternity testing.

[On problems of population in minority nationalities (author's transl)].

PIP: China's large population is made up mostly of Han people, but there are more than 50 other ethnic groups. Population policies must be made taking into consideration the different historical and economic characteristics of each group. An example of the ill effects of high population growth is the Lin Xia autonomous state, inhabitated by the Hui ethnic group. In 1956 living conditions and food supply were still good for a population of 839,000. By 1978 the population had increased to 1,370,000, per capita income had dropped from 80 yuans to 40 yuans, and gross agricultural product could not meet the needed food supply. Although the number of schools had increased, by 1978 32% of elementary school children, 10% of elementary school graduates, and 60% of junior high school graduates were unable to enter school for lack of facilities. The standard of education decreased, and unemployment increased. In 1973 the birth control program was initiated in the province. Natural increase went from 28.7% in 1973 to 14.7%, and the total birth rate was 58,232 births less than expected; result was an increased school budget and better food and clothing for all. The opposite problem is presented by the Akesa autonomous state of Hasake ethnicity. In 1949 the population of this ethnicity was 1700 people and the standard of living was high; however, natural population increase was only 1.5/1000, not enough to provide needed labor to cope with economical development. In this area population increase should be encouraged through various means of health care. As for other minorities living in areas mainly inhabited by other ethnic groups, they should keep their customs and beliefs but follow the population policies of the majority of the people. Birth control is a communist idea; it serves to improve the health and welfare of the whole nation, and it will not interfere with the stable unity of the various ethnicities.^ieng