Drug administration via hollow microneedles (HMN) have the advantages of painlessness, avoidance of first-pass effect, capability of sustained infusion, and no need for professional personnel operation. In addition, HMN can also be applied in the fields of body fluid extraction and biosensors, showing broad application prospects. However, traditional manufacturing technologies cannot meet the demand for low-cost mass production of HMN, limiting its widespread application. This paper reviews the main manufacturing technologies used for HMN in recent years, which include photolithography and etching, laser etching, sputtering and electroplating, micro-molding, three-dimensional (3D) printing and drawing lithography. It further analyzes the characteristics and limitations of existing manufacturing technologies and points out that the combination of various manufacturing technologies can improve production efficiency to a certain extent. In addition, this paper looks forward to the future trends of HMN manufacturing technology and proposes possible directions for its development. In conclusion, it is expected that this review can provide new ideas and references for follow-up research.
Printing, Three-Dimensional ; Needles ; Humans ; Drug Delivery Systems/methods* ; Equipment Design ; Microinjections/methods*

OBJECTIVE: To investigate the effects of combined platelet-rich plasma (PRP) and arterial supercharging technique on the survival rate and functional restoration of cross-body region skin flaps in rabbits. METHODS: Twelve healthy 6-month-old New Zealand White rabbits were randomly assigned to 4 groups ( n=3): sham group, PRP group, anastomosis group, and combined treatment group. An axial skin flap with an area of 12 cm×6 cm on the inner side of the hind limbs of all animals were prepared, with the saphenous artery as the main blood supply. Following the ligation of both the proximal and distal ends of the saphenous artery across all groups, the sham group received no further intervention, the PRP group was subjected to PRP injection, the anastomosis group underwent in situ end-to-end anastomosis of the distal saphenous artery, and the combined treatment group received both in situ distal saphenous artery anastomosis and PRP administration. Flap survival was evaluated and recorded on postoperative days 1, 3, and 7, with survival rates calculated accordingly. On day 7, flap tissue samples were harvested for HE staining to assess basal tissue morphology. Additionally, immunohistochemical staining was conducted to detect the expression of α-smooth muscle actin (α-SMA), vascular endothelial growth factor (VEGF), and CD31 in the flap tissues. RESULTS: At postoperative day 1, no significant difference in flap survival rates were observed among the 4 groups ( P>0.05). At day 3, the PRP group showed no significant difference compared to the sham group ( P>0.05); however, both the anastomosis and combined treatment groups exhibited significantly higher survival rates than the sham group ( P<0.05), the combined treatment group further demonstrated superior survival rates compared to both the PRP and anastomosis groups ( P<0.05). At day 7, the combined treatment group maintained significantly higher survival rates than all other groups ( P<0.05), while both the PRP and anastomosis groups exceeded the sham group ( P<0.05). HE staining at day 7 revealed persistent inflammatory cell infiltration, sheet-like erythrocyte deposition, and disordered collagen fibers in the sham group. The PRP group showed nascent microvessel formation and early collagen reorganization, whereas the anastomosis group displayed mature microvasculature with resolved interstitial edema. The combined treatment group exhibited differentiated microvessels with densely packed collagen bundles. Immunohistochemical analysis at day 7 demonstrated significantly larger relative area percentages of α-SMA, VEGF, and CD31 positive cells in the combined treatment group compared to all other groups ( P<0.05). Both the PRP and anastomosis groups also showed significantly higher values than the sham group ( P<0.05). CONCLUSION The combination of PRP and arterial supercharging techniques significantly enhances flap healing, potentially through mechanisms involving augmented angiogenesis and improved blood supply.
Animals ; Rabbits ; Platelet-Rich Plasma ; Surgical Flaps/blood supply* ; Graft Survival ; Anastomosis, Surgical/methods* ; Ischemia/surgery* ; Arteries/surgery* ; Skin/blood supply* ; Vascular Endothelial Growth Factor A/metabolism* ; Male ; Skin Transplantation/methods*

OBJECTIVE: To investigate the antioxidant and osteogenic induction capabilities of calcium phosphate nanoflowers (hereinafter referred to as nanoflowers) in vitro at different concentrations. METHODS: Nanoflowers were prepared using gelatin, tripolyphosphate, and calcium chloride. Their morphology, microstructure, elemental composition and distribution, diameter, and molecular constitution were characterized using scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and energy-dispersive spectroscopy. Femurs and tibias were harvested from twelve 4-week-old Sprague Dawley rats, and bone marrow mesenchymal stem cells (BMSCs) were isolated and cultured using the whole bone marrow adherent method, followed by passaging. The third passage cells were identified as stem cells by flow cytometry and then co-cultured with nanoflowers at concentrations of 0, 0.4, 0.8, 1.2, 1.6, 2.0, 2.4, 2.8, 3.2, and 3.6 mg/mL. Cell counting kit 8 (CCK-8) assay was performed to screen for the optimal concentration that demonstrated the best cell viability, which was subsequently used as the experimental concentration for further studies. After co-culturing BMSCs with the screened concentration of nanoflowers, the biocompatibility of the nanoflowers was verified through live/dead cell staining, scratch assay, and cytoskeleton staining. The antioxidant capacity was assessed by using reactive oxygen species (ROS) fluorescence staining. The in vitro osteoinductive ability was evaluated via alkaline phosphatase (ALP) staining, alizarin red staining, and immunofluorescence staining of osteocalcin (OCN) and Runt-related transcription factor 2 (RUNX2). All the above indicators were compared with the control group of normally cultured BMSCs without the addition of nanoflowers. RESULTS: Scanning electron microscopy revealed that the prepared nanoflowers exhibited a flower-like structure; transmission electron microscopy scans discovered that the nanoflowers possessed a multi-layered structure, and high-magnification images displayed continuous atomic arrangements, with the nanoflower diameter measuring (2.00±0.25) μm; energy-dispersive spectroscopy indicated that the nanoflowers contained elements such as C, N, O, P, and Ca, which were uniformly distributed across the flower region; Fourier transform infrared spectroscopy analyzed the absorption peaks of each component, demonstrating the successful preparation of the nanoflowers. Through CCK-8 screening, the concentrations of 0.8, 1.2, and 1.6 mg/mL were selected for subsequent experiments. The live/dead cell staining showed that nanoflowers at different concentrations exhibited good cell compatibility, with the 1.2 mg/mL concentration being the best (P<0.05). The scratch assay results indicated that the cell migration ability in the 1.2 mg/mL group was superior to the other groups (P<0.05). The cytoskeleton staining revealed that the cell morphology was well-extended in all concentration groups, with no significant difference compared to the control group. The ROS fluorescence staining demonstrated that the ROS fluorescence in all concentration groups decreased compared to the control group after lipopolysaccharide induction (P<0.05), with the 1.2 mg/mL group showing the weakest fluorescence. The ALP staining showed blue-purple nodular deposits around the cells in all groups, with the 1.2 mg/mL group being significantly more prominent. The alizarin red staining displayed orange-red mineralized nodules around the cells in all groups, with the 1.2 mg/mL group having more and denser nodules. The immunofluorescence staining revealed that the expressions of RUNX2 and OCN proteins in all concentration groups increased compared to the control group, with the 1.2 mg/mL group showing the strongest protein expression (P<0.05). CONCLUSION The study successfully prepares nanoflowers, among which the 1.2 mg/mL nanoflowers exhibits excellent cell compatibility, antioxidant properties, and osteogenic induction capability, demonstrating their potential as an artificial bone substitute material.
Animals ; Osteogenesis/drug effects* ; Mesenchymal Stem Cells/drug effects* ; Calcium Phosphates/pharmacology* ; Rats, Sprague-Dawley ; Rats ; Antioxidants/chemistry* ; Cells, Cultured ; Cell Differentiation/drug effects* ; Nanostructures/chemistry* ; Tissue Engineering/methods* ; Bone Marrow Cells/cytology* ; Coculture Techniques ; Tissue Scaffolds/chemistry* ; Male ; Biocompatible Materials/chemistry* ; Cell Survival ; Core Binding Factor Alpha 1 Subunit/metabolism* ; Cell Proliferation

Objective To propose a method for mitigate the impact of anomaly points(such as dust,bubbles,scratches on the chip surface,and minor indentations)in images on the results of digital droplet PCR(ddPCR)detection to achieve high-throughput,stable,and accurate detection.Methods We propose a Filter Faster R-CNN ddPCR detection model,which employs Faster R-CNN to generate droplet prediction boxes followed by removing the anomalies within the positive droplet prediction boxes using an outlier filtering module(Filter).Using a plasmid carrying a norovirus fragment as the template,we established a ddPCR dataset for model training(2462 instances,78.56%)and testing(672 instances,21.44%).Ablation experiments were performed to test the effectiveness of 3 filtering branches of the Filter for anomaly removal on the validation dataset.Comparative experiments with other ddPCR droplet detection models and absolute quantification experiments of ddPCR were conducted to assess the performance of the Filter Faster R-CNN model.Results In low-dust and dusty environments,the Filter Faster R-CNN model achieved detection accuracies of 98.23%and 88.35%for positive droplets,respectively,with composite F1 scores reaching 99.15%and 99.14%,obviously superior to the other models.The introduction of the filtering module significantly enhanced the positive accuracy of the model in dusty environments.In the absolute quantification experiments,a regression line was plotted using the results from commercial flow cytometry equipment as the standard concentration.The results show a regression line slope of 1.0005,an intercept of-0.025,and a determination coefficient of 0.9997,indicating high consistency between the two results.Conclusion The ddPCR detection technique using the Filter Faster R-CNN model provides a robust detection method for ddPCR under various environmental conditions.

Objective To clone the HnGUA gene from Hirudo nipponia and conduct bioinformatics analysis,protein prokaryotic expression analysis and gene differential expression analysis.Methods Based on the transcriptome data of H.nipponia in the previous study,the full-length cDNA of HnGUA was cloned by rapid amplification of cDNA ends(RACE),and bioinformatics analysis was performed.The prokaryotic expression vector was constructed,transformed into Escherichia coli BL21(DE3)competent cells and the expression of recombinant protein was induced by IPTG.The qPCR was used to further analyze the tissue-specific expression of HnGUA.Results The size of HnGUA gene was 504 bp,containing an open reading frame(ORF)of 231 bp and encoding 76 amino acids.Its protein molecular weight and isoelectric point are 8.17 kDa and 4.44,respectively.Multiple sequence alignment analysis showed that HnGUA was highly homologous to genes in other leech species that encode inhibitory proteins.The results of the prokaryotic expression analysis showed that the constructed pET32a-HnGUA vector could be successfully expressed in E.coli BL21(DE3),and the SDS-PAGE results showed that the induced recombinantly expressed HnGUA protein was around 6 kDa,which was basically consistent with the predicted protein size.The results of the Real-time PCR revealed spatial and temporal differences in the expression profiles of HnGUA,with high levels of expression detected in the skin and crop tissues.Conclusion This study represents the first successful cloning of the HnGUA gene from H.nipponia and the expression of the corresponding recombinant protein in E.coli.It provides a foundation for future exploration of the biosynthetic pathways and molecular regulatory mechanisms of active small anticoagulant molecules in leeches.

Objective To propose a method for mitigate the impact of anomaly points(such as dust,bubbles,scratches on the chip surface,and minor indentations)in images on the results of digital droplet PCR(ddPCR)detection to achieve high-throughput,stable,and accurate detection.Methods We propose a Filter Faster R-CNN ddPCR detection model,which employs Faster R-CNN to generate droplet prediction boxes followed by removing the anomalies within the positive droplet prediction boxes using an outlier filtering module(Filter).Using a plasmid carrying a norovirus fragment as the template,we established a ddPCR dataset for model training(2462 instances,78.56%)and testing(672 instances,21.44%).Ablation experiments were performed to test the effectiveness of 3 filtering branches of the Filter for anomaly removal on the validation dataset.Comparative experiments with other ddPCR droplet detection models and absolute quantification experiments of ddPCR were conducted to assess the performance of the Filter Faster R-CNN model.Results In low-dust and dusty environments,the Filter Faster R-CNN model achieved detection accuracies of 98.23%and 88.35%for positive droplets,respectively,with composite F1 scores reaching 99.15%and 99.14%,obviously superior to the other models.The introduction of the filtering module significantly enhanced the positive accuracy of the model in dusty environments.In the absolute quantification experiments,a regression line was plotted using the results from commercial flow cytometry equipment as the standard concentration.The results show a regression line slope of 1.0005,an intercept of-0.025,and a determination coefficient of 0.9997,indicating high consistency between the two results.Conclusion The ddPCR detection technique using the Filter Faster R-CNN model provides a robust detection method for ddPCR under various environmental conditions.

Objective:To compare the antiosteoporosis effect of conventional treatment and conventional treatment combined with Denosumab after percutaneous kyphoplasty (PKP) for osteoporotic vertebral compression fractures (OVCF).Methods:A retrospective cohort study was conducted to analyze the clinical data of 211 patients with OVCF admitted to the Second Affiliated Hospital of Soochow University from September 2020 to September 2022. All the patients were female, aged 56-90 years [(71.4±8.1)years]. The bone mineral density T-score of the lumbar spine was (-2.6±1.0)SD before operation. Fracture segments included T 1-T 9 in 45 patients, T 10-L 2 in 146, and L 3-L 5 in 69. Of all, 174 patients were treated with single-segment surgery, 25 with two-segment surgery and 12 with surgery involving three or more segments. According to the wishes of the patients, 107 patients were treated with daily oral administration of calcium and active Vitamin D after PKP (conventional treatment group) and 104 patients with Denosumab combined with the conventional treatment after PKP (Denosumab therapy group). The bone mineral density T-scores of the lumbar spine of the two groups were compared before surgery and at the last follow-up. The visual analogue scale (VAS) and Oswestry disability index (ODI) before surgery, at 3 days, 6 months after surgery, and at the last follow-up were evaluated and the refracture rate after surgery was detected. Possible adverse effects after medication during anti-osteoporosis treatment were observed in two the groups. Results:All the patients were followed up for 12-24 months [(13.5±2.0)months]. Before surgery, the bone mineral density T-score of the lumbar spine was (-2.7±1.1)SD in the Denosumab therapy group and (-2.5±0.8)SD in the conventional treatment group ( P>0.05). At the last follow-up, the bone mineral density T-score of the lumbar spine was (-2.1±1.1)SD in the Denosumab therapy group, significantly higher than (-2.5±0.9)SD in the conventional treatment group ( P<0.05). In the Denosumab therapy group, the bone mineral density T-score of the lumbar spine at the last follow-up was significantly increased compared to that before surgery ( P<0.01), while there was no significant difference in the conventional treatment group ( P<0.05). Before surgery and at 3 days after surgery, the VAS scores and ODI values were (8.5±0.9)points, (2.8±0.8)points, 48.7±4.8 and 25.6±4.0 in the Denosumab therapy group, which was not statistically different from those in the conventional treatment group [(8.5±1.3)points and (2.8±0.9)points, 47.9±7.0 and 25.9±3.7] ( P>0.05). At 6 months after surgery and at the last follow-up, the VAS scores and ODI values were (2.2±0.8)points, (1.7±0.8)points, 24.2±3.6 and 23.2±4.1 in the Denosumab therapy group, significantly lower than those of the conventional treatment group [(2.8±0.9)points, (2.8±1.1)points, 26.4±3.2 and 27.3±4.0] ( P<0.01). The VAS scores at each time point after surgery in both groups decreased significantly compared with those before surgery ( P<0.05). The VAS scores continued to decrease after surgery in the Denosumab therapy group ( P<0.05), while no significant difference was found among those at different time points in the conventional treatment group ( P>0.05). The ODI values at each time point after surgery in both groups significantly decreased compared to those before surgery ( P<0.05). The ODI values continued to decrease after surgery in the Denosumab therapy group ( P<0.05), while in the conventional treatment group, no significant difference was found between those at 6 months after surgery and those at 3 days after surgery ( P>0.05) and they were improved at the last follow-up compared with those at 3 days after surgery ( P<0.05). The refracture rate after surgery was 6.7% (7/104) in the Denosumab therapy group, significantly lower than 16.8% (18/107) in the conventional treatment group ( P<0.05). No serious complications were observed during the antiosteoporosis period in either group. Conclusion:Compared with daily oral administration of Calcium and active Vitamin D after PKP, the conventional treatment combined with Denosumab after PKP can effectively increase the bone density, relieve pain continuously, improve functional restoration, and reduce the risk of refracture in OVCF patients.

Objective:To analyze the dosimetric differences between gamma knife stereotactic body radiation therapy (SBRT) and linear accelerator-based SBRT for lung tumors by comparison to provide a theoretical basis for the selection of treatment strategies.Methods:Seven patients who underwent SBRT for lung tumors in the Cancer Center of Affiliated Zhongshan Hospital of Dalian University from January 2022 to May 2023 were enrolled. Plans of gamma knife SBRT (γ_SBRT) or linear accelerator-based SBRT plans (X_SBRT) were designed for the 13 lesions in the patients, with adjacent lesions in the same patient sharing one plan. As a result, 10 γ_SBRT plans and 10 X_SBRT plans were obtained. All lesions received 30-50 Gy of radiation in 5-10 fractions. Then, dosimetric parameters were analyzed and compared between γ_SBRT and X_SBRT plans, including the target coverage, gradient index (GI), conformity index (CI), maximum dose ( Dmax); mean dose ( Dmean), and minimum dose ( Dmin) of planning target volumes (PTVs); lung volumes receiving 20 Gy or more ( V20), 10 Gy or more ( V10), 5 Gy or more ( V5), 100% of the prescription dose ( V100%), and 50% of the prescription dose ( V50%); Dmean and the percentages of lung volume receiving doses of 20 Gy or more (Lung_ V20) and 5 Gy or more (Lung_ V5) of ipsilateral lung; Dmean and Lung_ V5 of contralateral lung; and Dmax values of the esophagus, spinal cord, and heart. Results:Compared to X_SBRT plans, γ_SBRT plans exhibited superior GI, V20, V10, V5, V50%, the Dmean, Lung_ V20, and Lung_ V5 of ipsilateral lung, the Dmean and Lung_ V5 of the contralateral lung, and the Dmax of esophageal and heart ( z = -2.81 to -1.99, P < 0.05), higher Dmax and Dmean of PTVs ( z = -2.80, -2.80, P < 0.05), and longer delivery time ( z=-2.70, P<0.05). Meanwhile, there was no significant difference in target coverage, CI, and Dmax of the spinal cord ( P > 0.05). Conclusions:Gamma knife SBRT plans can achieve sharper dose falloff outside target volumes than linear accelerator-based SBRT plans. Gamma knife radiosurgery is expected to reduce the radiation dose to low-dose areas around PTVs and normal lung tissue in SBRT for lung tumors. However, it significantly prolongs the delivery time.

Objective:To examine the clinical value of rapid detection of drug-resistant bacteria by immunochromatography and the effects of rapid detection on the prognosis of patients with severe intra-abdominal infection complicated by carbapenem-resistant Enterobacteriaceae (CRE) bloodstream infection.Methods:This was a retrospective cohort study. We analyzed clinical data of 73 patients with severe abdominal infections with sepsis or septic shock complicated by CRE bloodstream infection admitted to the general surgery department of Jinling Hospital between February 2022 and February 2023. Patients were divided into a colloidal gold immunochromatographic assay (GICA) group (17 patients) and conventional testing group (56 patients) based on whether a GICA for CRE had been performed on the patients' first blood culture sample during the diagnosis and treatment process. There were no statistically significant differences between the GICA and conventional testing groups in age ([55.9±17.3] vs. [47.6±16.4] years), sex ([16 men vs. one woman ] vs. [41 men vs. 15 women]), median Charlson comorbidity index (3.0[2.0,4.0] vs. 3.0[2.0, 4.8]), septic shock (10 vs. 39), or acute kidney injury (8 vs. 40) (all P>0.05). Both groups routinely underwent traditional bacterial identification and drug susceptibility testing. Additionally, patients in the GICA group were tested directly for positive blood cultures using a GICA carbapenemase test kit. The main outcomes were mortality rates on Days 28 and 90 after the first identification of CRE bloodstream infection in both groups. We also compared the microbial clearance rate, duration of hospitalization and intensive care unit stay, and time from onset of CRE bloodstream infection to initiation of targeted and appropriate antibiotics between the two groups. Results:The rate of microbial clearance of bloodstream infection was significantly greater in the GICA group than in the conventional testing group (15/17 vs. 34/56 [60.7%], χ 2=4.476, P=0.034), whereas the 28-day mortality tended to be lower in the GICA than conventional testing group [5/17 vs. 44.6% [25/56], χ 2=1.250, P=0.264). The 90-day mortality (8/17 vs. 53.6% [30/56], χ 2=0.222, P=0.638), median duration of hospitalization (37.0 [18.0, 46.5] days vs. 45.5 [32.2, 64.8] days, Z=-1.867, P=0.062), and median duration of intensive care unit stay (18.0 [6.5, 35.0] days vs. 32.0 [5.0, 51.8] days, Z=-1.251, P=0.209). The median time between the onset of bloodstream infection and administration of antibiotics was 49.0 (38.0, 69.0) hours in the GICA group, which is significantly shorter than the 163.0 (111.8, 190.0) hours in the conventional testing group ( Z=-5.731, P<0.001). The median time between the onset of bloodstream infection and administration of appropriate antibiotics was 40.0 (34.0, 80.0) hours in the GICA group, which is shorter than in the conventional testing group (68.0 [38.2, 118.8]) hours; however, this difference is not statistically significant ( Z=-1.686, P=0.093). Conclusions:GICA can provide information on carbapenemase- producing pathogens faster than traditional drug sensitivity testing, enabling early administration of the optimal antibiotics. The strategy of 'carbapenemase detection first' for managing bacterial infection has the potential to improve prognosis of patients and reduce mortality rate.