BACKGROUND:Scaffold materials serve as platforms that provide space and structure,playing a crucial role in the regeneration of cartilage tissue.Scholars from around the world are exploring different approaches to fabricate more ideal scaffold materials. OBJECTIVE:To review the design principles and preparation methods of cartilage scaffolds,and to further explore the advantages and limitations of various preparation methods. METHODS:Literature searches were conducted on the databases of CNKI,WanFang Data,PubMed,and FMRS from 1998 to 2023.The search terms were"cartilage repair,cartilage tissue engineering,cartilage scaffold materials,preparation"in Chinese and English.A total of 57 articles were ultimately reviewed. RESULTS AND CONCLUSION:(1)The articular cartilage has a unique structure and limited self-repair capacity after injury.Even if self-repair occurs,the newly formed cartilage is typically fibrocartilage,which is far inferior to normal articular cartilage in terms of structure and mechanical properties.It is difficult to maintain normal function and often leads to degenerative changes.Currently,the design and fabrication of scaffold materials for cartilage repair need to consider the following aspects:biocompatibility and biodegradability,suitable pore structure and porosity,appropriate mechanical properties,and bioactivity.(2)Research on the preparation of cartilage scaffolds has made significant progress,continuously introducing new preparation methods and optimization strategies.These methods have their advantages and disadvantages,providing more possibilities for customized preparation and functional design of cartilage scaffolds according to specific requirements.

BACKGROUND:Bone formation is the process by which osteoblasts synthesize and secrete osteoid and promote its mineralization,which generally involves mechanical signal transduction.Osteoblasts are primarily regulated by mechanical factors such as gravity,compressive stress,tensile stress,fluid shear stress,and hydrostatic pressure in vivo,and different mechanical stimuli modulate the proliferation,differentiation,and apoptosis of osteoblasts through various mechanisms,including hormones,cytoskeletal proteins,and microRNAs.By clarifying the effects of biomechanical forces on osteoblasts,it provides ideas and a reference basis for the treatment of osteometabolic diseases involving osteoblasts. OBJECTIVE:To review the effects of different biomechanical forces on the biological characteristics of osteoblasts. METHODS:We conducted a literature search using PubMed,Web of Science,FMRS,CNKI,and WanFang databases for relevant publications published from 2000 to 2023,covering basic research and tissue engineering studies related to the effects of biomechanical forces on osteoblasts.Ultimately,a total of 70 articles were reviewed. RESULTS AND CONCLUSION:Different biomechanical forces have an impact on the biological characteristics of osteoblasts,including proliferation,differentiation,and apoptosis,and these effects are dependent on the intensity and duration of the applied force.Specifically,the effects are as follows:(1)Under microgravity conditions,osteoblast proliferation and differentiation are inhibited,resulting in a decrease in bone density and the development of osteoporosis.(2)Compared to microgravity,hypergravity has a promoting effect on osteoblast proliferation.(3)The effects of compressive stress on osteoblasts are dependent on the loading intensity and time.Appropriate compressive stress can promote osteoblast proliferation and differentiation,which is beneficial for bone tissue formation and repair,while excessive compressive stress can cause osteoblast apoptosis and bone tissue destruction.(4)The biological effects of different types of tensile stress on osteoblasts differ.Studies have shown that a strain rate within the range of 0-12%has a promoting effect on osteoblast proliferation.(5)Fluid shear stress can promote osteoblast proliferation and differentiation and enhance the bone-inducing effect of biomaterials.(6)Static hydrostatic pressure can affect the biological behavior of osteoblasts,including proliferation,differentiation,and apoptosis,and these effects are closely related to the time and intensity of the pressure.Understanding the effects of different biomechanical forces on osteoblasts is of great significance for a deeper understanding of bone growth and maintenance mechanisms.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

Objective:To introduce and validate the Pediatric Nausea Assessment Tool (PeNAT) and the Baxter Retching Faces Scale (BARF) in the assessment of chemotherapy induced nausea in Chinese children with malignant neoplasms, and to explore the cut-off value for rescue antiemetic.Methods:A prospective descriptive study was conducted, 244 children in Sun Yat-sen University Cancer Center with malignant neoplasms who received chemotherapy were selected by convenience sampling from July to August 2021. PeNAT, BARF, Visual Analogue Scale (VAS) and the Faces Pain Scale-Revised(FPS-R) were used to assess the severity of nausea and pain before and after chemotherapy, before and 30-60 minutes after the use of rescue antiemetic or analgesic. After chemotherapy, the children also were asked the changes of nausea severity and whether antiemetic was needed.Results:A test-retest reliability was conducted on the patients with the same severity of nausea before and after chemotherapy, and the intraclass correlation coefficient of the PeNAT and BARF were 0.940 (both P<0.05). After chemotherapy, the PeNAT and BARF were 1.5(1.0, 2.0) and 2.0(0, 2.0) points, which were significantly higher than the 1.0(1.0, 1.0) and 0(0, 0) points before chemotherapy ( Z = - 9.19, - 9.09, both P<0.01). The PeNAT and BARF of 11 cases receiving antiemetic before medication were 4.0 (4.0, 6.0) and 3.0(2.0, 4.0) points, which were higher than the 0(0, 2.0) and 1.0(1.0, 2.0) points without antiemetic ( Z = - 4.03, - 3.86, both P<0.05). After chemotherapy, the correlation coefficients between PeNAT or BARF and VAS-nausea were r = 0.933, 0.957 (both P<0.01), and FPS-R were r = 0.192, 0.189 (both P<0.05). After using antiemetic, PeNAT and BARF were 2.0(2.0, 3.0) and 2.5(2.0, 4.0) points, which were significant different than the 3.0(3.0, 3.8) and 4.0(4.0, 8.0) points before using antiemetic ( Z = - 2.97, - 2.83, both P<0.05). According ROC curves and cut-off values, it was determined that PeNAT≥3 and BARF≥4 had clinical significance and require clinical intervention. Conclusions:PeNAT and BARF have excellent reliability and validity in the assessment of chemotherapy induced nausea in children with malignant neoplasms, they can effectively identify the requirement of rescue antiemetic, and evaluate the efficacy of antiemetic.

Objective:To investigate the impact of switching to low iodine drinking water in areas with high water iodine levels on the iodine nutritional status and thyroid function of pregnant women.Methods:A cross-sectional survey was conducted in Gaoqing County, Zibo City, Shandong Province. Pregnant women who underwent prenatal examinations at the Obstetrics Clinic of Gaoqing County People's Hospital from 2019 to 2021 were selected as the survey subjects. With reference to the Criteria for the Classification of Water Source High Iodine Areas and High Iodine Disease Areas (GB/T 19380-2016), pregnant women with drinking water iodine > 100 μg/L were considered as the high water iodine group and ≤100 μg/L was the non-high water iodine group. Basic information, one random urine sample, fasting blood sample, 24-hour urine sample and drinking water sample of pregnant women were collected, and thyroid ultrasound examination was performed on pregnant women. Urinary iodine (UI) concentration (UIC) and drinking water iodine concentration (WIC) were measured by inductively coupled plasma mass spectrometry, and 24-hour urinary iodine excretion (UIE) and daily iodine intake (TII) of pregnant women were calculated. Serum thyroid hormone (TSH), free triiodothyronine (FT 3), free thyroxine (FT 4), thyroid peroxidase antibody (TPOAb) and anti-thyroid autoantibodies (TgAb) were determined by automatic chemiluminescence immunoassay. Creatinine (CR) was determined using deproteinized endpoint microplate method and UI/CR was calculate. Results:A total of 797 pregnant women were included, and the UIC was 150.2 (88.1, 281.3) μg/L, the iodine nutrition was generally at an appropriate level. Among them, 584 pregnant women in the non-high water iodine group had a UIC of 120.9 (74.9, 191.5) μg/L, which was at the iodine deficiency level; 213 pregnant women in the high water iodine group had a UIC of 321.1 (201.9, 569.1) μg/L, which was at the iodine super-appropriate level; the differences in WIC, UIC, UIE, TII, and UI/CR between the two groups were statistically significant ( Z = 21.63, 13.34, 15.14, 15.14, 11.81, P < 0.001). After stratification by different gestational periods, the differences were statistically significant when comparing WIC and TSH in pregnant women in the non-high water iodine group and UI/CR in pregnant women in the high water iodine group by gestational period ( H = 59.13, 7.30, 13.60, P < 0.05). A total of 744 pregnant women were tested for thyroid function, and 128 cases of TSH > 2.5 mU/L, 15 cases of hypothyroxemia, and 19 cases of subclinical hypothyroidism were detected, with detection rates of 17.2%, 2.0%, and 2.6%, respectively. The differences were statistically significant when comparing TSH and TPOAb levels and the proportion of pregnant women with TSH > 2.5 mU/L in the high water iodine and non-high water iodine groups ( Z = 3.04, - 2.17, χ 2 = 6.94, P = 0.002, 0.030, 0.008). The thyroid glands of pregnant women were examined in 720 cases, and 30 cases of goiter and 150 cases of thyroid nodules were detected, with detection rates of 4.2% and 20.8%, respectively. The median thyroid volume was 8.92 ml in the high water iodine group and 8.60 ml in the non-high water iodine group, which were both within the normal range, with no statistically significant difference between the groups ( Z = - 0.75, P = 0.455). Conclusions:After changing to low iodine water, the overall iodine nutrition of pregnant women in Gaoqing County is now at an appropriate level, and the reduction of water iodine effectively reduces the risk of TSH abnormalities in local pregnant women. However, pregnant women in the non-high water iodine group are iodine deficiency, and pregnant women in the high water iodine group are at iodine super-appropriate, and the iodine nutrition level of pregnant women in this area is highly variable, which causes the "illusion" that the overall iodine level of local pregnant women is suitable.

Objective:To observe the urinary iodine content (UIC), breast milk iodine content (BMIC) and milk iodine excretion of lactating rats under different iodine nutrition levels, and to explore the iodine metabolism of the lactating rats under different iodine nutrition levels.Methods:Forty female Wistar rats with body weight ranging from 70 to 120 g were divided into low iodine (LI) group, normal iodine (NI) group, hight iodineⅠ (HIⅠ) group and hight iodine Ⅱ (HIⅡ) group according to body weight by random number table method, with 10 rats in each group. The rats were fed low-iodine diet, and the iodine ion concentration of drinking water in each group was 0, 325, 18 700 and 37 450 μg/L. Twenty male rats were fed according to the feed method of NI group. After 8 weeks of intervention, the male and female rats were caged and mated in a ratio of 1 ∶ 2. Milk and 24 h urine were collected on the 7th, 14th and 21st days of lactation (L7, L14 and L21), and the amount of food and drinking water consumed were recorded. The 24 h milk excretion was calculated by acute lactation test. UIC and BMIC were determined by inductively coupled plasma mass spectrometry (ICP-MS).Results:The 24 h total iodine intake of lactating rats in LI, NI, HIⅠ and HIⅡ groups were (1.84 ± 0.51), (30.51 ± 6.79), (765.95 ± 317.41) and (1 654.26 ± 560.55) μg/d, respectively. The difference between groups was statistically significant ( P < 0.001). At L7, L14 and L21, there were statistically significant differences in UIC, BMIC and milk iodine excretion at the same lactation stages among different groups ( P < 0.001). In HIⅡ group, the difference of BMIC and milk iodine excretion at different lactation stages (L7, L14, and L21) were significantly signrficant ( P < 0.05). The 24 h milk iodine excretion of LI, NI, HIⅠ and HIⅡ groups was (1.23 ± 0.85), (11.88 ± 5.23), (207.09 ± 114.51), (493.67 ± 242.47) μg, respectively. The proportion of 24 h milk iodine excretion to 24 h total iodine intake was 66.85%, 38.94%, 27.04% and 29.84%, respectively. Conclusions:About 39% of dietary iodine is supplied to offspring through milk when iodine nutrition is normal. The iodine excretion ratio of milk is increased or decreased with low and high iodine levels. These results indicate that lactating rats with different iodine nutrition levels can regulate the ratio of iodine excretion in milk through their own compensatory effect to reduce the influence of iodine deficiency and iodine excess on their offspring.

Objective:Healthy life expectancy (HLE), which combines life expectancy with health, is an essential comprehensive measure of life length and quality. This article aimed to systematically review the methods for defining and measuring HLE and describe application studies published, providing a reference for decision makers to select and develop methods suitable for China's conditions to measure HLE.Methods:Seven Chinese and English literature databases were searched up to May 7, 2022, and several related reviews and bibliography were manually retrieved. Systematic reviews and empirical research were included concerning HLE indicators and measurement of HLE. Information including the study area, type of the study, study population, HLE index, measurement method, data sources, and results from application studies published in the last five years were extracted. The evolution of the definition of HLE, the scope of different indicators, the measurement scale of health, and measurement methods, were all collected. Results of the empirical research related to measurement methods of indicators were summarized. The study followed the scoping review framework and was written according to the PRISMA-ScR statement.Results:A total of 84 articles were included, including 13 reviews, 17 original studies related to HLE index definition, ten original studies related to index measurement, and 44 empirical studies conducted in the past five years. There were as many as 20 indicators related to HLE, and each scale had its emphasis. A total of ten methods measuring HLE were identified, which vary in the definition of health, whether using weight, and the data type. The most commonly used indicators in the past five years were disability-free life expectancy and HLE. For the method of HLE calculation, Sullivan's method was mainly used for cross-sectional data, and the multistate life table was mainly used for longitudinal data.Conclusions:There are various definitions and measurement methods of HLE, but none are suitable for all scenarios. To summarize the HLE concept, health evaluation techniques, measurement methods, and application studies published worldwide can provide a reference for the localization of HLE measurement in China.

Objective : To explore the technology and efficacy of fabrication of a guide and removal of a fiber post by tetrahedron positioning technology at the chair side. Methods: For one patient with acute chronic periapical periodontitis of the left maxillary lateral incisor who needed to have the fiber post removed, the chair side tetrahedral positioning technique was used to make a guide plate to remove the fiber post. Cone beam CT (CBCT) data were imported into the software to design the guide plate for fiber post removal. The guide plate design on CBCT was transferred to a solid model by using tetrahedral positioning technology. The guide plate was made to guide the removal of the fiber post, and then left maxillary lateral incisor root canal was performed. We evaluated the effect of fiber post removal with tetrahedral positioning technology by reviewing the literature. Results : The guide plate made by tetrahedral positioning technology can accurately locate the position and direction of fiber posts at a low cost and with high speed. After the fiber post was removed, the root canal could be dredged by using root canal preparation instruments. After root canal preparation, the root canal was filled with warm gutta-percha to complete the root canal treatment. After 3 months, the apical radiograph showed that the transmission shadow of the apical area was reduced. The results of the literature review showed that the fiber post removal with guide plates provides a predictable result and a lower risk of iatrogenic damage. Minimally invasive treatment can be carried out, and chair time can be reduced. Conclusion On the basis of CBCT data, using tetrahedral positioning technology to make fiber post removal guides can help reduce the risk of fiber post removal and has the characteristics of speed, low cost and short chair side processing. However, the accuracy comparison between tetrahedral positioning technology and 3D printing guides needs further study.

Objective To investigate MR findings and analyze the misdiagnosed cases of pituitary macroadenoma.Methods MR features of 1 90 patients of pituitary macroadenoma confirmed by operation and pathology were reviewed.Results 1 6 cases were mis-diagnosed as craniopharyngioma,chordoma,or meningioma.Among the sixteen cases,eight cases with cyst degeneration and hemor-rhage were misdiagnosed as craniopharyngioma;five cases with clival and sphenoid sinus destruction were misdiagnosed as chordo-mas;three cases with suprasellar and anterior cranial fossa extension were misdiagnosed as meningiomas.Conclusion Craniophar-yngioma,chordoma and meningioma should be considered in the differential diagnosis of atypical pituitary macroadenoma.The com-prehensive analysis should be based on a variety of signs.

Objective To explore the value of pretargeting technology in vitro MRI of L5 peptide guided streptavidin-conjugated and polyethylene glycol modification protected ultra-small superparamagnetic iron oxide(SA-PEG-USPIO) to hepatocellular carcinoma(HCC) via glypican-3(GPC3) receptor.Methods Direct immumofluorescence assay with carboxyfluorescein(FAM) labeled L5 and competitive inhibition was performed in HepG2 and HL-7702 cells.Imaging was obtained from fluorescent microscope.Immunoassay fluorescence images were carried out to determine the expression of GPC3 in HepG2 cell.PEG-USPIO conjugated with streptavidin was made by carbodiimide reaction,and the hydrodynamic diameters,Zeta potential and magnetic relaxivity of SA-PEG-USPIO and PEG-USPIO were measured.HL7702 cells were used for evaluate cells viability of SA-PEG-USPIO and PEG-USPIO.HepG2 and HL-7702 cells were used as experimental and control group respectively.Each of the two cell lines were further divided into three groups:L5-BT united SA-PEG-USPIO group,SA-PEG-USPIO group and control group.Prussian blue staining and MRI was preformed to observe the targeting efficacy of SA-PEG-USPIO respectively,and normalized T2 signal was recorded.The significant changes of normalized T2 signal intensity among groups was deterumine by using One-way analysis of variance.Results There were much more fluorescences on the membrane and cytoplasm of HepG2 cells than those on HL-7702 cells and cells of competition group.And indirect immunofluorescence images show the obvious expression of GPC3 in HepG2 cell.The SA-PEG-USPIO and PEG-USPIO nanoparticles had hydrodynamic diameters of (22.73 ± 3.31) and (35.97±5.19)nm,Zeta potential of them were (4.22±0.53) and (-7.91± 1.22)mV and magnetic relaxivity were 0.139 4× 103 and 0.103 9 × 103 mM-1s1.Although the highest concentration of SA-PEG-USPIO and PEG-USPIO was 2.4 mmol/L,cells viability was greater than 80％.The most iron particle was observed in L5-BT united SA-PEG-USPIO group of HepG2 cells.In vitro MR,the normalized T2 signal intensity of HepG2 cells in L5-BT united SA-PEG-USPIO group,SA-PEG-USPIO group and control group were 39±7,77 ± 12 and 93 ± 4.There was significant difference among those three groups (F=23.96,P＜0.01).The normalized T2 signal intensity of HL-7702 cells in each of three groups were 69± 11,78±8 and 95±5.There was no significant difference among those three groups (F=2.86,P＞0.05).Conclusion By the pretargeting method,L5 peptide guided SA-PEG-USPIO has effective targeting ability to HepG2 cells in vitro.