BACKGROUND:Titanium implants are widely used in clinical practice because of their high strength and good biocompatibility.However,during implantation,bacterial infection and tissue damage environment produce a large number of reactive oxygen species,which can easily lead to delayed tissue healing and surgical failure.Consequently,the development of titanium implants with antimicrobial and antioxidant properties becomes paramount. OBJECTIVE:Considering the potent antimicrobial attributes of copper ions and the remarkable antioxidant qualities of polyphenols,we proposed the fabrication of polyphenol-mediated copper ion coatings on titanium surfaces.These coatings were subsequently assessed for their in vitro antimicrobial and antioxidant properties. METHODS:Nanostructures were generated on the titanium surface using the alkali thermal method.The titanium was immersed in a solution containing tannic acid and copper ions to achieve polyphenol-mediated copper ion coatings.The surface morphology and water contact angle were detected.The loading and release of copper ions were examined using atomic absorption spectroscopy.Staphylococcus aureus was inoculated on the surface of pure titanium sheet(blank group),alkali heat treated titanium sheet(control group),and polyphenol mediated copper ion modified titanium sheet(experimental group)to observe the bacterial survival status.Osteoblast precursor cells MC3T3-E1 were co-cultivated on the surface of three groups of titanium sheets to assess their antioxidant properties and bioactivity. RESULTS AND CONCLUSION:(1)Scanning electron microscopy showed that the polyphenol-mediated copper ion modified titanium sheet had rod-like nanostructures and no cracks on the surface.The surface hydrophilicity of copper ion modified titanium sheet mediated by polyphenol was close to that of pure titanium sheet.Atomic absorption spectrometry results showed a 51%increase in the loading capacity of copper ions after polyphenol mediation,with a uniform release of copper ions.(2)The antibacterial rates of titanium sheets in the blank group,control group,and experimental group were 0%,21.65%,and 93.75%,respectively.The live/dead staining and CTC staining showed that the live bacteria on the surface of titanium plates in the blank group were the most,and the live bacteria on the surface of titanium plates in the experimental group were the least.(3)The results of live/dead staining and CCK-8 assay showed that the three groups of titanium sheets had good cytocompatibility,and the titanium sheets in the experimental group were more conducive to the proliferation of MC3T3-E1 cells.Active oxygen fluorescence probe detection exhibited that compared with the other two groups,the fluorescence intensity of active oxygen on the surface of the experimental group was significantly reduced.The results of alkaline phosphatase and alizarin red S staining showed that the osteogenic differentiation and extracellular matrix mineralization of MC3T3-E1 cells on the surface of titanium sheets in the experimental group were stronger than those in the other two groups.(4)These results show that the polyphenol-mediated copper ion coating has strong antibacterial and antioxidant properties and promotes osteogenic differentiation.

Objective:To investigate the current status of application of stereotactic body radiation therapy (SBRT) in China, aiming to provide reference for promoting the development of this technology.Methods:From January to March 2024, a questionnaire was designed and distributed online, targeting member units of the Professional Committee of Stereotactic Radiosurgery Treatment, which covers 175 radiotherapy units in 30 provinces and regions nationwide. The survey focused on the current application of SBRT technology and its utilization in the treatment of early-stage non-small cell lung cancer (NSCLC). A statistical description of the survey results was presented.Results:Of 175 questionnaires distributed, a total of 130 valid responses were collected, with an effective response rate of 74.3%. A total of 81.5% (106/130) of the units had implemented SBRT technology, and 99.1% of the respondents believed it was necessary to further promote SBRT technology, yet the actual training rate was only 67.0%. SBRT equipment configuration: there were a total of 267 SBRT equipment, featuring a diverse range of types, with traditional linear accelerators as the mainstays, accounting for 76.0% ( n=203), followed by 12.0% ( n=32) for TOMO, 6.4% ( n=17) for Cyber knife, 3.7% ( n=10) for Gamma knife, and proton/heavy ion equipment at 1.5% ( n=4), respectively. The percentage of units with multi-leaf collimator leaf widths ≤0.5 cm was 93.4% (99/106). The application of SBRT: the first radiotherapy unit commenced SBRT in 2000, and this technology entered a period of rapid growth after 2015, sustaining a steady increase over the past decade; SBRT technology was mainly applied in the brain, lung, liver, bone, adrenal gland, and kidney, with application rates of 97.2%, 94.3%, 86.8%, 71.7%, 56.6%, and 27.4%, respectively, while the application rates for the pancreas, metastatic lymph nodes, and other parts were less than 5%. Current status of SBRT technology application in early-stage NSCLC: 90.6% (96/106) of units had implemented SBRT; pre-treatment multi-disciplinary diagnosis and treatment accounted for 77% (74/96); the proportion of application units for peripheral and central type lung cancer lesions both exceeded 57.3%, whereas the application rate for ultra-central type and lesions > 5 cm lung cancer was less than 30%; there was significant variability in the selection of reference guidelines, dose fractionation patterns, and the concept of central type among units. Conclusions:The development of SBRT technology in China is in a period of steady growth, but several issues such as low training rate and lack of standardization still exist. The survey results provide important reference for clinical training and promotion of SBRT technology in China.

Gene synthesis is an enabling technology that supports the development of synthetic biology. The existing approaches for de novo gene synthesis generally have tedious operation, low efficiency, high error rates, and limited product lengths, being difficult to support the huge demand of synthetic biology. The assembly and error correction are the keys in gene synthesis. This study first designed the oligonucleotide sequences by reasonably splitting the virus genome of approximately 10 kb by balancing the parameters of sequence design software ability, PCR amplification ability, and assembly enzyme assembly ability. Then, two-step PCR was performed with high-fidelity polymerase to complete the de novo synthesis of 3.0 kb DNA fragments, and error correction reactions were performed with T7 endonuclease Ⅰ for the products from different stages of PCR. Finally, the virus genome was assembled by 3.0 kb DNA fragments from de novo synthesis and error correction and then sequenced. The experimental results showed that the proposed method successfully produced the DNA fragment of about 10 kb and reduced the probability of large fragment mutations during the assembly process, with the lowest error rate reaching 0.36 errors/kb. In summary, this study developed an efficient de novo method for synthesizing a viral genome of about 10 kb with T7 endonuclease Ⅰ-mediated error correction. This method enabled the synthesis of a 10 kb viral genome in one day and the correct plasmid of the viral genome in five days. This study optimized the de novo gene synthesis process, reduced the error rate, simplified the synthesis and assembly steps, and reduced the cost of viral genome assembly.
Genome, Viral/genetics* ; Polymerase Chain Reaction/methods* ; DNA, Viral/genetics* ; Bacteriophage T7/enzymology* ; Synthetic Biology/methods*

BACKGROUND:Iron overload is an independent factor inducing osteoporosis,but the action mechanism is currently unclear.Therefore,exploring the effects of iron overload on osteoblast-related cells will help to deeply understand the pathogenesis of osteoporosis and provide potential strategies for osteoporosis treatment.OBJECTIVE:To explore the effects of iron overload environment on osteoblast precursor cell activity,ferroptosis,and osteogenic differentiation.METHODS:Osteoblast precursor cells(MC3T3-E1 cells)were divided into blank group,iron overload group,fer-1 group,and deferoxamine group.The iron overload group was treated with 300 μmol/L ammonium ferric citrate in the culture medium for 48 hours to simulate the iron overload microenvironment.The cells in fer-1 group and deferoxamine group were pretreated with 5 μmol/L antioxidant fer-1 and 5 μmol/L deferoxamine for 8 hours,respectively,and then added with 300 μmol/L ammonium ferric citrate for 48 hours.CCK-8 assay was used to determine the cell viability.Intracellular reactive oxygen species levels were detected employing a reactive oxygen species fluorescent probe.Changes in mitochondrial membrane potential were monitored with a mitochondrial membrane potential fluorescent probe.Mitochondrial morphology was observed employing transmission electron microscopy.Cellular glutathione levels were measured with a reduced glutathione colorimetric assay kit.Lipid peroxidation levels were assessed with a malondialdehyde colorimetric assay kit.Cellular ferrous ion levels were determined with a ferrous ion colorimetric assay kit.The osteogenic and mineralization capabilities of the cells were verified by alkaline phosphatase staining and alizarin red staining.Collagen secretion ability was detected using Sirius Red staining.The expression of osteogenic/ferroptosis-related genes and proteins was examined through reverse transcription quantitative polymerase chain reaction and western blot analysis.RESULTS AND CONCLUSION:(1)In an iron-overload environment,the mitochondrial membrane potential of cells decreased and their structure was compromised,with an elevation in intracellular lipid peroxidation levels and a downregulation of genes and proteins associated with ferroptosis resistance.However,pretreatment with fer-1 and deferoxamine led to an increase in mitochondrial membrane potential and partial restoration of morphology,a reduction in intracellular lipid peroxidation levels,and an upregulation of genes and proteins related to ferroptosis resistance.(2)In an iron-overload environment,the levels of cellular alkaline phosphatase,the formation of mineralized nodules,and the synthesis of collagen fibers were all found to be decreased.Pretreatment with fer-1 and deferoxamine was observed to upregulate the expression of osteogenic differentiation in cells.(3)In summary,iron overload could increase intracellular oxidative stress levels,mediate ferroptosis in MC3T3-E1 cells and inhibit osteogenic differentiation,thereby inducing osteoporosis.Therefore,maintaining iron homeostasis and inhibiting osteogenesis-related ferroptosis may be potential strategies to prevent or treat osteoporosis.

BACKGROUND:Iron overload is an independent factor inducing osteoporosis,but the action mechanism is currently unclear.Therefore,exploring the effects of iron overload on osteoblast-related cells will help to deeply understand the pathogenesis of osteoporosis and provide potential strategies for osteoporosis treatment.OBJECTIVE:To explore the effects of iron overload environment on osteoblast precursor cell activity,ferroptosis,and osteogenic differentiation.METHODS:Osteoblast precursor cells(MC3T3-E1 cells)were divided into blank group,iron overload group,fer-1 group,and deferoxamine group.The iron overload group was treated with 300 μmol/L ammonium ferric citrate in the culture medium for 48 hours to simulate the iron overload microenvironment.The cells in fer-1 group and deferoxamine group were pretreated with 5 μmol/L antioxidant fer-1 and 5 μmol/L deferoxamine for 8 hours,respectively,and then added with 300 μmol/L ammonium ferric citrate for 48 hours.CCK-8 assay was used to determine the cell viability.Intracellular reactive oxygen species levels were detected employing a reactive oxygen species fluorescent probe.Changes in mitochondrial membrane potential were monitored with a mitochondrial membrane potential fluorescent probe.Mitochondrial morphology was observed employing transmission electron microscopy.Cellular glutathione levels were measured with a reduced glutathione colorimetric assay kit.Lipid peroxidation levels were assessed with a malondialdehyde colorimetric assay kit.Cellular ferrous ion levels were determined with a ferrous ion colorimetric assay kit.The osteogenic and mineralization capabilities of the cells were verified by alkaline phosphatase staining and alizarin red staining.Collagen secretion ability was detected using Sirius Red staining.The expression of osteogenic/ferroptosis-related genes and proteins was examined through reverse transcription quantitative polymerase chain reaction and western blot analysis.RESULTS AND CONCLUSION:(1)In an iron-overload environment,the mitochondrial membrane potential of cells decreased and their structure was compromised,with an elevation in intracellular lipid peroxidation levels and a downregulation of genes and proteins associated with ferroptosis resistance.However,pretreatment with fer-1 and deferoxamine led to an increase in mitochondrial membrane potential and partial restoration of morphology,a reduction in intracellular lipid peroxidation levels,and an upregulation of genes and proteins related to ferroptosis resistance.(2)In an iron-overload environment,the levels of cellular alkaline phosphatase,the formation of mineralized nodules,and the synthesis of collagen fibers were all found to be decreased.Pretreatment with fer-1 and deferoxamine was observed to upregulate the expression of osteogenic differentiation in cells.(3)In summary,iron overload could increase intracellular oxidative stress levels,mediate ferroptosis in MC3T3-E1 cells and inhibit osteogenic differentiation,thereby inducing osteoporosis.Therefore,maintaining iron homeostasis and inhibiting osteogenesis-related ferroptosis may be potential strategies to prevent or treat osteoporosis.

Objective:To investigate the current status of application of stereotactic body radiation therapy (SBRT) in China, aiming to provide reference for promoting the development of this technology.Methods:From January to March 2024, a questionnaire was designed and distributed online, targeting member units of the Professional Committee of Stereotactic Radiosurgery Treatment, which covers 175 radiotherapy units in 30 provinces and regions nationwide. The survey focused on the current application of SBRT technology and its utilization in the treatment of early-stage non-small cell lung cancer (NSCLC). A statistical description of the survey results was presented.Results:Of 175 questionnaires distributed, a total of 130 valid responses were collected, with an effective response rate of 74.3%. A total of 81.5% (106/130) of the units had implemented SBRT technology, and 99.1% of the respondents believed it was necessary to further promote SBRT technology, yet the actual training rate was only 67.0%. SBRT equipment configuration: there were a total of 267 SBRT equipment, featuring a diverse range of types, with traditional linear accelerators as the mainstays, accounting for 76.0% ( n=203), followed by 12.0% ( n=32) for TOMO, 6.4% ( n=17) for Cyber knife, 3.7% ( n=10) for Gamma knife, and proton/heavy ion equipment at 1.5% ( n=4), respectively. The percentage of units with multi-leaf collimator leaf widths ≤0.5 cm was 93.4% (99/106). The application of SBRT: the first radiotherapy unit commenced SBRT in 2000, and this technology entered a period of rapid growth after 2015, sustaining a steady increase over the past decade; SBRT technology was mainly applied in the brain, lung, liver, bone, adrenal gland, and kidney, with application rates of 97.2%, 94.3%, 86.8%, 71.7%, 56.6%, and 27.4%, respectively, while the application rates for the pancreas, metastatic lymph nodes, and other parts were less than 5%. Current status of SBRT technology application in early-stage NSCLC: 90.6% (96/106) of units had implemented SBRT; pre-treatment multi-disciplinary diagnosis and treatment accounted for 77% (74/96); the proportion of application units for peripheral and central type lung cancer lesions both exceeded 57.3%, whereas the application rate for ultra-central type and lesions > 5 cm lung cancer was less than 30%; there was significant variability in the selection of reference guidelines, dose fractionation patterns, and the concept of central type among units. Conclusions:The development of SBRT technology in China is in a period of steady growth, but several issues such as low training rate and lack of standardization still exist. The survey results provide important reference for clinical training and promotion of SBRT technology in China.

Objective:To explore the effect of accurately localized mini anterolateral thigh perforator flap in repairing medium-sized skin and soft tissue defects in fingers.Methods:The study was a retrospective observational study. From December 2019 to September 2022, 15 patients with medium-sized skin and soft tissue defects who met the inclusion criteria in fingers were admitted to the Second Affiliated Hospital of Wenzhou Medical University, including 12 males and 3 females, aged 23 to 62 years. After debridement, the wounds were all accompanied by exposed tendons, bones, vessels and nerves, with an area from 4.0 cm×3.0 cm to 8.0 cm×3.5 cm. Computed tomography angiography and color Doppler ultrasonography examinations were performed on both lower limbs of the patient before surgery to accurately locate the anterolateral thigh perforators. When the flap with area from 6.0 cm×3.0 cm to 11.0 cm×4.0 cm was harvested, the flap was thinned. The artery and vein perforators of the flap were anastomosed respectively with the digital artery and dorsal metacarpal vein. If there was avulsion injury, infection, or burn in the recipient area, the main arterial and veinous vessels carried by the skin flap was anastomosed with the radial artery and accompanying vein. The lateral thigh cutaneous nerve carried by the flap was anastomosed with the stump of the digital nerve. The types of perforators of the lateral thigh artery were observed during operation and compared with the location of the vessels before operation. After operation, the survival and adverse complication of the flap were closely observed. During follow-up, the skin flap color, texture, and shape were observed; the wound healing in donor area was observed. At the last follow-up, the two-point discriminative distance of the affected finger pulp was measured, and the function of the affected finger was evaluated using the trial standard for the evaluation of functions of upper limbs of Hand Surgery Society of Chinese Medical Association, and the interphalangeal joint movement of the affected finger was observed; the patients' complaints about the adverse effects of flap resection on lower limbs were recorded.Results:During the operation, it was observed that the perforators of the flaps in 11 patients were the descending branch of the lateral circumflex thigh artery, in two patients, the perforators of skin flaps were the oblique branch of the lateral thigh artery, and the perforators in another two patients were the transverse branch of the lateral circumflex thigh artery, which were consistent with the preoperative vascular localization. After operation, all flaps survived without vascular crisis and infection. The patients were followed up for 6-12 months, the flaps had excellent color, texture, and appearance; only linear scars remained on the donor wound. At the last follow-up, the two-point discrimination distance in the finger pulp was 7-11 mm; the affected finger function was rated as excellent in 6 cases, good in 6 cases, and fair in 3 cases; the flexion and extension function of the finger was not affected; two patients complained of numbness in the lateral thigh after excision of the skin flap, and the other 13 patients had no complain of adverse complaints.Conclusions:The perforating branch in lateral thigh region can be accurately located by computed tomography angiography and color Doppler ultrasonography, accurate positioning of perforators before operation can reduce the damage to the donor area during the incision of the flap, the appearance and function of the affected finger can be restored to the maximum extent by thinning the transplanted flap and rebuilding the finger sensation. Therefore, it is an effective and reliable way to repair the medium-sized skin and soft tissue defects of fingers with the mini thigh anterolateral perforator flap.

Objective:To investigate the effects of different radiotherapy regimens on the short-term and long-term prognosis of patients with limited-stage small cell lung cancer (SCLC).Methods:Sixty patients with limited-stage SCLC in the Third People′s Hospital of Yangquan City from September 2017 to September 2019 were selected. The patients who received concurrent radiotherapy and chemotherapy were in group A and the patients who received sequential radiotherapy and chemotherapy were in group B, 30 cases in each group. The short-term efficacy and adverse reactions of the two groups were compared, and the levels of neuron-specific enolase (NSE), gastrin release precursor (ProGRP), carcinoembryonic antigen (CEA), vascular endothelial growth factor (VEGF), endostatin (ES), circulating endothelial cells (CEC) were compared between the two groups. The survival status of the two groups were followed-up.Results:After treatment, the disease control rate in group A was higher than that in the group B : 80.00%(24/30) vs. 53.33%(16/30), the difference was statistically significant ( χ2 = 4.80, P<0.05). The levels of serum NSE, ProGRP and CEA in the group A after treatment were lower than those in the group B: (19.42 ± 3.31) pg/L vs. (24.58 ± 4.42) pg/L, (95.45 ± 10.33) ng/L vs. (115.54 ± 15.66) ng/L, (8.25 ± 1.02) μg/L vs. (10.33 ± 1.15) μg/L, the differences were statistically significant ( P<0.05). The levels of VEGF and CEC in the group A were lower than those in the group B after treatment and ES was higher than that in the group B: (356.62 ± 56.63) ng/L vs. (442.21 ± 55.38) ng/L, (65.56 ± 5.41) × 10 6/L vs. (99.28 ± 7.24) ×10 6/L, (52.65 ± 6.44) μmol/L vs. (31.85 ± 5.49) μmol/L, the differences were statistically significant ( P<0.05). There was no significant difference in the incidence of adverse reactions between the two groups ( P>0.05). The survival rate in the group A was higher than that in the group B at 1 year after treatment: 82.14%(23/28) vs. 56.00%(14/25), the difference was statistically significant ( χ2 = 4.28, P = 0.038). Conclusions:Compared with sequential radiotherapy and chemotherapy, concurrent radiotherapy and chemotherapy is effective in treating limited-stage SCLC, which can adjust the level of tumor markers and angiogenesis indicators, and improve the treatment effect and survival rate.

Objective:To compare the effects of two methods of marking surface landmarks on the patient’s positional stability when using a multifunctional body board in combination with thermoplastics to fix the abdominal and pelvic areas for radiotherapy patients.Methods:50 subjects who underwent positional fixation using a multifunctional body board in combination with thermoplastics from August 2022 to January 2023. The subjects were divided into two groups, A and B, with 25 cases each, according to the different methods of body surface marking. In group A, landmarks were marked on the body surface on the top edge of the thermoplastics. In group B, three sets of surface landmarks were marked on the patient’s body according to the laser line on the projection of the patient’s body surface when the thermoplastics were completed. Manual registration is performed using L3 to L5 as the main registration targets. The pre-treatment CBCT image is used to analyze the first-time positioning pass rate, setup errors in the x-, y-, and z-axis directions, and the distribution of positive and negative setup errors in both groups of patients. Results:The pass rates of the first-time positioning of patients in Groups A and B were 76.9% and 86.1%, respectively, which met the clinical requirements. Group B had a better first-time positioning pass rate than group A, and the difference between the two groups was statistically significant ( P < 0.05). The pendulum errors of group B were smaller than those of group A in both the x-axis and y-axis (all P < 0.05), and the difference between the two groups in terms of the pendulum errors in the z-axis direction was not statistically significant (all P > 0.05). The difference in the frequency distribution of the pendulum error in the positive and negative directions of the x- and z-axis between the two groups was not statistically significant (all P > 0.05). The difference in the frequency of distribution of the pendulum error in the positive and negative directions of the y-axis between the two groups was statistically significant ( P < 0.05). Conclusions:The proposed two methods of surface landmark marking are generally in line with the positioning requirements for conventional fractionation radiotherapy for abdominal and pelvic patients. Using a laser line on the projection of the patient’s body surface for three sets of surface landmark markings produces smaller setup errors and is better than using the top edge of the thermoplastics for surface landmark markings, improving the positional stability of abdominal and pelvic patients.

Resource utilization is an effective way to cope with the rapid increase of kitchen waste and excess sludge, and volatile fatty acids produced by anaerobic fermentation is an important way of recycling organic waste. However, the single substrate limits the efficient production of volatile fatty acids. In recent years, volatile fatty acids produced by anaerobic co-fermentation using different substrates has been widely studied and applied. In this paper, we analyze the characteristics of fermentation to produce acid using kitchen waste and excess sludge alone or mixture. Influences of environmental factors and microbial community structure on the type and yield of volatile fatty acids in the anaerobic fermentation system are discussed in detail. Moreover, we propose future research directions, to provide a reference for recycling kitchen waste and excess sludge.
Anaerobiosis ; Bioreactors ; Fatty Acids, Volatile ; Fermentation ; Hydrogen-Ion Concentration ; Microbiota ; Organic Chemicals ; Sewage