In this paper, the effects of the blend of nanoparticles and microneedle matrix materials on the mechanical properties of dissolving microneedles were studied mainly, so as to construct microneedles with excellent mechanical properties. Different kinds of nanoparticles (calcium carbonate, hydroxyapatite, silica), particle sizes (20, 60, 100 nm) and the proportion of prescription (2%, 6%, 10%) were blended with the matrix material [polyvinyl pyrrolidone (PVP), poly(1-vinylpyrrolidone-co-vinyl acetate)(PVP/VA)] to form dissolving microneedles. The effects of nanoparticles on the elastic modulus and hardness of the microneedles were investigated using a nanoindenter. The results showed that the elastic modulus and hardness of PVP microneedles were significantly improved by nano-calcium carbonate (P < 0.001), and the elastic modulus and hardness of PVP/VA microneedles were significantly improved by nano-hydroxyapatite (P < 0.001). When the particle size of hydroxyapatite was 20 nm, the elastic modulus of PVP/VA microneedles was (10.6 ± 1.0) GPa, and the hardness was (0.47 ± 0.06) GPa. As the size of the nanoparticles increases, the mechanical performance of the microneedles decreases. When the mass proportion of nano-hydroxyapatite increased from 2% to 6%, the elastic modulus and hardness of the microneedles were significantly improved (P < 0.001), but the effect of continue increasing the proportion of nanoparticles on the microneedles was not significant. The nano-enhanced PVP/VA dissolving microneedles has no irritant effect on intact skin and has a slight irritation to damaged skin, but they disappear completely after 72 h. Animal experiments have been approved by the Laboratory Animal Welfare and Ethics Committee of Zhejiang University of Technology. Therefore, the nano-enhanced dissolving microneedles has good biological safety. To sum up, it is necessary to select the appropriate kind of nanoparticle, particle size, and prescription ratio when microneedles constructing with a given matrix material, so as to effectively improve its mechanical performance.

To investigate the influence factors and effects of metal or dissolving microneedles on the formation and healing of skin microchannels, the pencil-shaped or conical stainless steel microneedles with different lengths, tip to tip space and base area, and the pencil-shaped dissolving microneedles with different tip to tip space were used. The microneedles were applied to the skin of epilatory mice and rats, and the effects of various microneedle parameters, application parameters, and animals on the microchannels were explored by the transepidermal water loss (TEWL) and methylene blue staining. Visually observe the skin local irritation caused by the microneedles. The animal experiments were approved by the Animal Experiments Welfare and Ethical Committee of Zhejiang University of Technology. The application time of the microneedle should be maintained at 30 s or more. When the insertion forces were 2, 4, 8 N, and the TEWL initial values of the formed microchannels were 12.9, 33.0, 40.4 g·m^-2·h^-1, respectively. When the length of metal microneedle were 400, 600, 800 μm, and the TEWL initial values of the formed microchannels were 37.1, 40.4, 49.5 g·m^-2·h^-1, respectively. When the tip to tip space of metal microneedle were 400, 600, 800 μm, and the TEWL initial values of the formed microchannels were 33.2, 40.4, 55.8 g·m^-2·h^-1, respectively. When the base area of metal microneedle were 0.16, 0.35, 0.62 cm², and the TEWL initial values of the formed microchannels were 35.1, 40.4, 67.1 g·m^-2·h^-1, respectively. The effects of conical and pencil-shaped microneedles are similar. When the tip to tip space of pencil shaped dissolving microneedle were 400, 600, 800 μm, and the TEWL initial values of the formed microchannels were 49.8, 60.5, 70.5 g·m^-2·h^-1, respectively. The TEWL baseline values of animal skins of different genders and series are different, but the tendency of microchannels formation and closure is similar. Visual inspection revealed that the slight erythema caused by the microneedles subsided within 24 h. Microneedles of different parameters have different effects on microchannels. The microchannels closed within 24 or 48 h, and the skin local irritation caused by microneedle was mild.

As a novel transdermal drug delivery technology of minimally invasive, safe and efficient, microneedles have received increasing attention. The microchannels formation by microneedles onto the skin is a prerequisite and key for microneedles to deliver drugs. However, there is still a lack of systematic evaluation in skin microchannels. This review summarized influencing factors and evaluation methods in microchannels formation and healing by microneedles, including geometric parameters, materials for preparation, drugs, penetration parameters, differences among the skin of subjects, and presence or absence of occlusion. This review provides reference for other scholars to further study the effectiveness and security of microneedle applications.

Objective To study the correlation between level of nitric oxide/ nitricoxide synthase(NO/NOS) on placenta homogenate and ultra-structure changes of placenta in pregnancy lead exposure in rats.Methods Seventeen normal pregnant rats and 46 rats of exposured in lead which were divided into A,B,C groups were studied.The level of NO/NOS of placenta were measured by nitrate reductase and NOS kit.Placentas were randomly selected from each group to detect ultra-structure by electron-microscope.Results There were significant difference among A,B and control groups on level of NO/NOS(all P0.05).Compensation hyperplasy or minor injury were observed in lead exposure of stage groups.Lead exposure during whole gestation period,the lead level was maxmum,and decompensation were observed on placental construction.Conclusions There is a close correlations between level of lead,NO/NOS and pathological change of placental tissue,and both of them may play an important role in the pathogenesis of peripartum lead exposure.

ObjectiveTo investigate the prognostic value of the enhancement pattern in arterial phase of preoperative Gd-EOB-DTPA enhanced magnetic resonance imaging （MRI） in evaluating the disease-free survival （DFS） and overall survival （OS） in patients undergoing curative resection for intrahepatic cholangiocarcinoma （ICC）. MethodsA retrospective analysis was done on the clinical， preoperative MRI findings and postoperative follow-up results of 93 pathologically confirmed ICC patients undergoing surgery in our hospital between January 2018 and December 2021. Kaplan-Meier survival curves and log-rank test were used to compare the DFS and OS of three groups with different arterial enhancement patterns. Cox regression analysis was used to identify the factors affecting DFS and OS. ResultsThere were significant differences in DFS and OS among the 3 groups （log-rank test， P < 0.05）. The arterial enhancement pattern was an independent predictive factor for DFS （using diffuse hyperenhancement as a reference， peripheral rim enhancement： HR = 3.550； 95%CI： 1.16 ~ 10.8； P = 0.026；diffuse hypoenhancement： HR = 3.430； 95%CI： 1.04 ~ 11.3； P = 0.042）. The arterial enhancement pattern and tumor location were predictive factors for OS （（using diffuse hyperenhancement as a reference， diffuse hypoenhancement， HR = 8.500； 95%CI： 1.09-66.3； P = 0.041； using tumor distal location as a reference， tumor perihilar location HR=2.583，95%CI： 1.14-5.83， P =0.022）. The AUC of arterial enhancement patterns in predicting 1-， 2-， and 3- year DFS were 0.722， 0.748， and 0.617， respectively； in OS， 0.720， 0.704， and 0.730， respectively， which showed better prognostic efficacy than AJCC-TNM staging system. ConclusionArterial-phase enhancement pattern of preoperative Gd-EOB-DTPA enhanced MRI is an independent predictive factor for DFS and OS of ICC patients， with a better prognostic value than AJCC-TNM staging system， and can be used for the clinical management of ICC patients.

Fcγ receptorIIIa (FcγRIIIa) polymorphism was considered to influence clinical response to therapeutic monoclonal antibody (MAb) against cancer, which is suggested to affect MAb binding and MAb-dependent NK cell-mediated cytotoxicity. The purpose of this study was to examine the FcγRIIIa gene polymorphisms in healthy children and in children with hematological malignancy, and to explore its possible effect on MAb in children with hematological malignancies. 43 healthy children (H) and 20 pediatric patients with hematological malignancies (HM) were enrolled in this study. DNA was isolated from peripheral blood, and then nest-polymerase chain reaction-restriction fragment length polymorphism (nest-PCR and PCR-RFLP) was used to determine the FcγRIIIa-158 genotypes in each groups of subject, digested fragments were subjected to electrophoresis on 15% PAGE. The results showed that there were a higher frequencies of FcγRIIIa-158V/F in H and HM group (72.1% and 75.0% respectively), the frequencies of FcγRIIIa-158V/V were 27.9% and 25.0% in H and HM group respectively, but there was no FcγRIIIa-158F/F in the two groups. No significant difference in distribution of the FcγRIIIa-158 genotype was found between HM and H groups (p > 0.05). It is concluded that FcγRIIIa-158V/F is more frequent, while FcγRIIIa-158V/V is less, but FcγRIIIa-158F/F is very rare in both groups. No significant difference of FcγRIIIa polymorphism distribution is found between healthy and hematological malignancy groups.
Adolescent ; Case-Control Studies ; Child ; Child, Preschool ; Female ; Genotype ; Hematologic Neoplasms ; genetics ; Humans ; Male ; Polymorphism, Genetic ; Receptors, IgG ; genetics

The quantitative identification and enrichment of viable regulatory T cells (Treg) requires reliable surface markers that are selectively expressed on Treg. Foxp3 is the accepted marker of natural Treg, but it cannot be used to isolate cells for functional studies. CD127 is a new surface marker expressed in Treg cells. In this study, two populations of Treg, including CD4(+)CD25(+)CD127(low/-) and CD4(+)CD25(+)Foxp3(+)T cells, and profiles of the Foxp3 expression in CD4(+)CD25(+)CD127(low/-) cells were compared to evaluate which population is better. The peripheral blood cells were collected and spleen suspension of BALB/C mice were prepared, and using triple staining CD4, CD25, CD127 and CD4, CD25, Foxp3. The profiles of Treg, including CD4(+)CD25(+)CD127(low/-) and CD4(+)CD25(+)Foxp3(+) were detected by flow cytometry. The quadruple staining CD4, CD25, Foxp3 and CD127 were used to determine the CD127 expression in CD4(+)CD25(+)Foxp3(+) cells. The results showed that on T cell subset the median expression levels of CD4(+), CD4(+)CD25(+) were 39.02%, 5.35% in peripheral blood and 23.49%, 3.86% in spleen. On CD4(+) T cell subset, the median expression level of CD4(+)CD25(+)CD127(low/-) and CD4(+)CD25(+)Foxp3(+)T cells were 7.13%, 3.97% in peripheral blood and 12.8%, 8.23% in spleen. The ratio of CD4(+)CD25(+)CD127(low/-) T cells was higher than that of CD4(+)CD25(+)Foxp3(+) cells in both peripheral blood and spleen cells (P < 0.01). The CD4(+)CD25(+)CD127(low/-) cells highly expressed Foxp3, while the CD4(+)CD25(+)Foxp3(+)T cells lowly expressed CD127. It is concluded that compared with the CD4(+)CD25(+)Foxp3(+) populations, CD4(+)CD25(+)CD127(low/-) T cells better fit the definition of naturally occurring regulatory T cells in peripheral blood cells and spleen of BALB/C mice. CD127(low/-) is a characteristic marker on surface of CD4(+)CD25(+) Treg cells, and has been confirmed to be more specific marker for quantitatively sorting Treg cells.
Animals ; Biomarkers ; blood ; Female ; Interleukin-7 Receptor alpha Subunit ; analysis ; Mice ; Mice, Inbred BALB C ; Spleen ; cytology ; T-Lymphocytes, Regulatory ; metabolism

OBJECTIVETo observe the effects of pravastatin on platelet-derived nitric oxide system in hypercholesterolemia (HC) and atherosclerosis (AS) in rabbits, and the relationship between these changes and atherosclerosis courses.

METHODSThirty male New Zealand white rabbits were randomly divided into three groups, 12 in group A, 12 in group B, and 6 in group C. All of them were fed daily with cholesterol-rich food during the first 12 weeks. In addition, in group A, pravastatin (10 mg) was orally administered daily. At the end of the 12th week, 6 in group A and B were killed randomly and their aortas were removed and the pathologic changes were observed. In the following 12 weeks, food enriched with cholesterol was substituted with normal food in all three groups. Pravastatin treatment was continued or started in the remaining members of group A and group B, but not in group C. At the end 24th week, all rabbits were killed and their aortas were examined for the fatty-streaks or atherosclerotic plaques. The expressions of endothelial NOS (eNOS) mRNA and inducible NOS (iNOS ) mRNA, NOS activity, NO production and the level of the serum lipids were measured at 0, 6th, 12th, 18th and 24th week.

RESULTSThe expression levels of platelet-derived NOS mRNA, eNOS mRNA ratio in group A had no difference at above time points, while in group B were reduced significantly at 6th week and 12th week compared with at 0 week (P <0.01), and increased at 18th week and 24th week compared with 12th week (P <0.05). The expression levels of eNOS mRNA in group C were reduced at 6th, 12th and 18th, 24th week compared with 0 week (P <0.05 and P <0.01, respectively), and were reduced in groups B and C compared with group A at 6th ,12th week (P < 0.05) and increased in group A and B compared with group C at 18th, 24th week (P <0.01). The expression levels of iNOS/mRNA among the three groups had no difference. Pathologic finding of the arteries: AS was not found in group A from the 12th to 24th week. While in group B, there were a lot of fatty-streaks on the entire intima of all large arteries at the 12th week. There were also fatty-streaks in the ascending aorta, but were improved at the 24th week. In group C, there were marked plaques in the entire aorta at the 24th week.

CONCLUSIONSThe expressions of platelet-derived eNOS mRNA, NOS activity, NO production are decreased in HC or AS rabbits. Pravastatin can up-regulate expressions of platelet-derived eNOS mRNA, NOS activity, leading to preventing or improving the pathological courses of AS.

Animals ; Atherosclerosis ; blood ; pathology ; Blood Platelets ; metabolism ; Disease Models, Animal ; Male ; Nitric Oxide ; blood ; genetics ; Nitric Oxide Synthase ; blood ; genetics ; Pravastatin ; pharmacology ; RNA, Messenger ; genetics ; Rabbits

OBJECTIVETo describe the characteristics of child pedestrian traffic injuries among aged 0-14 years old in Guangzhou city and to provide information on road, vehicle and human injuries in pedestrian.

METHODSA database of all motor vehicle crashes involving child pedestrian traffic injury cases over a five-year period (2000-2004), was from the police department.

RESULTSThe annual pedestrian traffic injury rates on incidence, mortality and case fatality were 17.63/ 1,100,000, 1.78/ 100,000 and 10.07% respectively. Both incidence rate and mortality peaked in the 5-9 age group were 26.80/ 100,000 and 2.57/ 100,000, with case fatality peaked in the 0-4 age group (13.29%). For males, the incidence (20.98/ 100,000) and mortality (2.00/ 100,000) were higher than that in females (13.83/ 100,000, and 1.52/ 100,000). The main injured parts of body would include multi-areas (40.34%), head (26.75%) and lower limbs (21.53%). 10.07% of the cases died and 66.18% and 23.75% of them having had severe and slight injures. The major causes were due to drivers (57.50%) and pedestrians (33.47%) faults with top three responsible vehicles were cars (40.14%), two-wheeled motorcycles (34.38%) and vans (22.15%).

CONCLUSIONData from pediatric pedestrian injury poses a threat to children and adolescents, data suggesting that it is important to change behaviors of both drivers and pedestrians.

Accidents, Traffic ; statistics & numerical data ; Adolescent ; Age Distribution ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Wounds and Injuries ; epidemiology

AIMTo study the synthesis and antitumour activities of some aryl-substituted pteridines.

METHODSA series of aryl-substituted pteridines were synthesized from 4, 6-diamino-5-nitrosopyrimidines by cyclization with 4-aminophenylacetonitriles. The antitumour activities were tested by MTT method.

RESULTSNine new compounds (I-III) were synthesized and their structures were characterized by EA, IR, 1HNMR and MS spectra. Compounds I-III showed antitumour activities in vitro.

CONCLUSIONCompounds I-III showed remarkable antitumour activities in vitro. No interaction was determined between the title compounds and calf thymus DNA. It indicated that these compounds possibly inhibit dihydrofolate reductase (DHFR) or other enzymes on which folic acid depends.

Adenocarcinoma ; pathology ; Antineoplastic Agents ; chemical synthesis ; chemistry ; pharmacology ; Cell Line, Tumor ; drug effects ; Humans ; KB Cells ; drug effects ; Lung Neoplasms ; pathology ; Molecular Structure ; Pteridines ; chemical synthesis ; chemistry ; pharmacology