Abstract: Objective　To analyze and understand the mutations of drug resistance genes in imported Plasmodium falciparum in Shenzhen, aiming to assess the efficacy of antimalarial drugs and guide effective drug use. Methods A total of 85 samples from individuals with imported Plasmodium falciparum confirmed by fluorescence quantitative polymerase chain reaction (PCR) in Shenzhen from 2022 to 2023 were collected and genomic DNA was extracted. Nested PCR was used to amplify resistance genes, including Plasmodium falciparum Kelch 13 (PfK13), multidrug resistance gene 1 (Pfmdr1), chloroquine resistance transporter (Pfcrt), dihydrofolate reductase (Pfdhfr), and dihydropteroate synthase (Pfdhps) genes. Bidirectional sequencing was conducted, and mutations in these resistance genes were analyzed using MEGA11.06 software. Results　The study found one missense mutation (S549P) and four synonymous mutations in PfK13. For Pfmdr1, 62.69% of the samples showed Y184F mutation, and no N86Y mutation was detected. No mutations at positions 72 and 73 were detected in the Pfcrt gene, while mutations at M74I, N75E, and K76T accounted for 17.46%, 15.87%, and 15.87%, respectively. The wild-type of Pfcrt gene is dominant (82.54%, 52), followed by the triple mutant I74E75T76 (15.87%, 10). The most common mutation type for Pfdhfr is I51R59N108 (91.78%, 67), followed by the wild type (2.74%, 2). More than half (60.32%, 38) of the Pfdhps samples were wild-type, with single mutation K540E being the most common mutation type. S436A, G437A, K540E, A581G, A613S, I431V, G556K, and G579E site mutations were detected. Among the Pfdhfr-Pfdhps combination mutations, I51R59N108-E540 was the most frequent combination mutation (11.48%), with 59.02% of samples showing solitary Pfdhfr mutations. Conclusions In this study, PfK13 mutation rates were low, with no reported resistance mutations. The Y184F mutation emerged as the dominant Pfmdr1 mutation, with no detection of N86Y. For Pfcrt, the wild-type was dominant, followed by the I74E75T76 triple mutation variant. Triple mutant I51R59N108 of Pfdhfr was very common, and our study did not find Pfdhfr Pfdhps completely resistant and super resistant mutants, but there were other quintuple and septuple mutant types. In the future, it is crucial to continue to strengthen the monitoring of malaria parasite resistance genes and to further integrate in vivo efficacy monitoring to effectively guide clinical drug use.

Objective To analyze coating properties of porous artificial joints,including coating morphology and coating mechanical properties,and summarize the range of coating properties of current mainstream products,to provide references for the design and development of new products,as well as provide the basis for the long-term implant removal analysis.Methods Samples for the surface morphology,shear strength,and tensile strength of the coatings used in the experiment were prepared in accordance with ASTM F1854,ASTM F1044,and ASTM F1 147 standards,respectively.The coatings were processed using plasma spraying.The surface morphology(coating thickness,porosity,and pore intercept)of the coatings for all 17 products(Nos.1-17)was tested;for products Nos.1-7 and Nos.15-16,the shear strength test between the coating and substrate was conducted first in accordance with the test method of ASTM F1044.Then,according to the test method of ASTM F1 147,the tensile strength test between the coating and substrate was conducted.For product No.17,the shear and tensile strengths of the composite coating and simple titanium coating were tested,respectively,according to the test method of ASTM F1044 and ASTM F1 147.Results A total of 15 products(88.2％)had coating thicknesses between 300 μm and 500 μm.There were 16 metal-coated products(Nos.1-16),of which 11(68.75％of the total)had coating porosities between 30％and 50％,and 14(87.5％of the total)had coating pore intercepts between 50 μm and 150 μm.The mechanical properties of the coatings were independent of the substrate material used.The shear and tensile strengths of the composite coatings with hydroxyaptite(HA)were significantly lower than those of the pure metal coatings.Conclusions For the design and manufacture of artificial joints with porous coatings,the performance of the coating can be referred to the following indexes:the coating thickness is 300-500 μm,the coating porosity is 30％-50％,the coating pore intercept is 50-150 μm.The substrate materials can be selected based on the use of the product.The effects of a lower bonding force on product performance should be considered when designing prostheses with composite coatings containing HA.This range of performance metrics provides control for long-term clinical extraction analyses.

Objective To perform laboratory detection and molecular traceability analysis on a case of imported kala-azar in Shenzhen to determine the infection strain. Methods Bone marrow puncture fluid and blood samples from a case of kala-azar in Shenzhen were collected for laboratory tests. The patient's bone marrow puncture fluid smears were stained with Giemsa and examined under a microscope. Blood samples were examined for antibodies using the rk39 visceral leishmania rapid diagnostic reagent. Whole blood DNA was extracted, and the ITS-1 sequence was amplified by PCR, sequenced and aligned, and a phylogenetic tree was constructed based on the ITS-1 sequence. Results Microscopic examination of the patient's bone marrow smears revealed a large number of Leishmania amastigotes without flagella, confirming the diagnosis of kala-azar. The patient's blood was tested positive with the rk39 rapid diagnostic reagent, and PCR amplification yielded an ITS-1 gene product sequence that matched the expected size. Sequence alignment with the NCBI database showed 100% sequence similarity with the ITS-1 gene sequence of Leishmania infantum, confirming the infecting strain as Leishmania infantum. Phylogenetic tree construction of the amplified ITS-1 sequence revealed clustering into a clade with Leishmania infantum , and close to KC347299, one of the reference sequence selected. Conclusions The case of kala-azar in Shenzhen was caused by Leishmania infantum. Kala-azar still occurs in China, so the diagnostic technology of medical personnel in non-epidemic areas should be strengthened so that they can actively use new diagnostic technologies to assist in diagnosis, thus improving their prevention and control ability of Leishmania parasites.

Cystic echinococcosis, a zoonotic disease that poses a significant threat to human health and animal husbandry development, is prevalent across the world and predominantly occurs in agricultural and pastoral regions. However, cystic echinococcosis cases are rare in non-endemic areas, which is likely to cause misdiagnosis or missing diagnosis, resulting in delay in treatment. This report presents an overseas imported cystic echinococcosis case misdiagnosed as pulmonary and hepatic cysts, so as to provide insights into diagnosis and treatment of cystic echinococcosis in non-endemic areas.

Objective To explore the application effect of 3D printed heart models in the training of young cardiac surgeons, and evaluate their application value in surgical simulation and skill improvement. Methods Eight young cardiac surgeons were selected form West China Hospital as the trainees. Before training, the Hands-On Surgical Training-Congenital Heart Surgery (HOST-CHS) operation scores of the 8 cardiac surgeons were obtained after operating on 2 pig heart models of ventricular septal defect (VSD). Subsequently, simulation training was conducted on a 3D printed peri-membrane VSD heart model for 6 weeks, once a week. After the training, all trainees completed 2 pig heart VSD repair surgeries. The improvement of doctors’ skills was evaluated through survey questionnaires, HOST-CHS scores, and operation time after training. Results Before the training, the average HOST-CHS score of the 8 trainees was 52.2±6.3 points, and the average time for VSD repair was 54.7±7.1 min. During the 6-week simulation training using 3D printed models, the total score of HOST-CHS for the 8 trainees gradually increased (P<0.001), and the time required to complete VSD repair was shortened (P<0.001). The trainees had the most significant improvement in scores of surgical cognition and protective awareness. The survey results showed that trainees were generally very satisfied with the effectiveness of 3D model simulation training. Conclusion The 3D printed VSD model demonstrates significant application advantages in the training of young cardiac surgeons. By providing highly realistic anatomical structures, 3D models can effectively enhance surgeons’ surgical skills. It is suggested to further promote the application of 3D printing technology in medical education, providing strong support for cultivating high-quality cardiac surgeons.

The standardized workflow of computer-aided static guided implant surgery includes preoperative exami-nation,data acquisition,guide design,guide fabrication and surgery.Errors may occur at each step,leading to irrevers-ible cumulative effects and thus impacting the accuracy of implant placement.However,clinicians tend to focus on fac-tors causing errors in surgical operations,ignoring the possibility of irreversible errors in nonstandard guided surgery.Based on the clinical practice of domestic experts and research progress at home and abroad,this paper summarizes the sources of errors in guided implant surgery from the perspectives of preoperative inspection,data collection,guide de-signing and manufacturing and describes strategies to resolve errors so as to gain expert consensus.Consensus recom-mendation:1.Preoperative considerations:the appropriate implant guide type should be selected according to the pa-tient's oral condition before surgery,and a retaining screw-assisted support guide should be selected if necessary.2.Da-ta acquisition should be standardized as much as possible,including beam CT and extraoral scanning.CBCT performed with the patient's head fixed and with a small field of view is recommended.For patients with metal prostheses inside the mouth,a registration marker guide should be used,and the ambient temperature and light of the external oral scan-ner should be reasonably controlled.3.Optimization of computer-aided design:it is recommended to select a handle-guided planting system and a closed metal sleeve and to register images by overlapping markers.Properly designing the retaining screws,extending the support structure of the guide plate and increasing the length of the guide section are methods to feasibly reduce the incidence of surgical errors.4.Improving computer-aided production:it is also crucial to set the best printing parameters according to different printing technologies and to choose the most appropriate postpro-cessing procedures.

Objective:To evaluated the safety and feasibility of dissection of lymph nodes posterior to right recurrent laryngeal nerve (ⅥB compartment) in endoscopic thyroidectomy through gasless axillary posterior approach.Methods:A total of 350 cases with right lobe papillary thyroid carcinoma (PTC) who underwent endoscopic lobectomy, isthmusectomy and central compartment neck dissection via gasless axillary posterior approach based at the Department of General Surgery, Nanfang Hospital, Southern Medical University from June 2020 to December 2022 were retrospectively analyzed. Summarize the clinical, pathological characteristics, and postoperative complications of the patients. SPSS 25.0 was used for statistical analysis of the data.Results:All 350 patients underwent endoscopic surgery successfully, with no conversion to open surgery. There were 303 females and 47 males, with an average age of (36.3±9.2) years. Of those, 287 patients were in pT1a stage, 62 in pT1b stage, and one patient in pT2 stage. There was no T3 or T4 stage patient. The mean numbers of yielded lymph nodes in right central compartment and ⅥB compartment were 8.11±4.65 (range, 1-31) and 2.62±1.86 (range, 1-12), respectively. ⅥB compartment metastasis was detected in 52 (14.86%) of 350 patients. The incidence of transient recurrent laryngeal nerve injury was 0.86%(3/350). Postoperative hematoma occurred in three patients (0.86%).Conclusion:The dissection of ⅥB compartment in endoscopic thyroidectomy through gasless axillary posterior approach is safe and feasible in selected PTC patients

Objective:To investigate the risk factors of post-stroke depression (PSD) in patients with first acute stroke 6 months after onset.Methods:Three hundred and sixty-seven patients with acute stroke who were treated for the first time in the Affiliated Hospital of Xuzhou Medical University were selected retrospectively. After onset for 6 months, the patients were followed up and divided into PSD group and non-PSD group. The clinical data, blood index, imaging data, degree of nerve damage and the patient's stigma level were compared between the two groups.Results:Totally 182 and 185 cases were included in the PSD and non-PSD groups, respectively. The incidence of PSD at 6 months post-stroke was 49.6% (182/367). The results of univariate analysis showed that diseased region, drinking history, monthly income, standard of culture, serum cortisol, total cholesterol (TC), high sensitivity C-reactive protein (hs-CRP), neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), Stigma Scale for Chronic Illness-8 Chronic Disease Stigma Scale-8(SSCI-8) scores, National Institute of Health Stroke Scale (NIHSS) scores and subtype of stroke were risk factors for PSD ( P<0.05). Binary Logistic regression analysis showed that diseased region at frontal lobe ( OR = 3.245, P = 0.011), basal ganglia region ( OR = 2.820, P = 0.007), cerebellar hemisphere ( OR = 4.594, P = 0.010) and serum cortisol ( OR = 1.174, P<0.001), hs-CRP ( OR = 1.057, P<0.001), SSCI-8 scores ( OR = 1.674, P<0.001), NIHSS scores ( OR = 1.283, P<0.001) were independent risk factors for PSD. Conclusions:PSD is a common complication in patients with stroke. Diseased region (at frontal lobe, basal ganglia region, cerebellar hemispheres), hs-CRP, serum cortisol, level of morbidity stigma and degree of neurological impairment are development risk factors for the PSD at 6 months of acute stroke.

Ferroptosis is an iron-dependent novel type of programmed cell death. The main features of ferroptosis include lipid reactive oxygen accumulation, iron accumulation and lipid peroxidation. The main mechanisms and signal pathways of ferroptosis are complex and closely related to cystine/glutamate antiporter system, glutathione peroxidase 4, ferroptosis suppressor protein 1, and dihydroorotate dehydrogenase. This review summarizes the current regulatory mechanisms of ferroptosis and discusses the research progress of ferroptosis in tumors, non-alcoholic fatty liver disease, Parkinson's disease, and congestive heart failure.

Objective:To study the patterns of tocilizumab (TCZ) use, its efficacy and safety in patients with rheumatoid arthritis (RA) in routine clinical practice.Methods:A total of 407 patients with RA were enrolled from 23 centers and treated with TCZ within 8 weeks prior to the enrollment visit, and were followed for 6-month. The patterns of TCZ treatment at 6 months, the effectiveness and safety outcomes were recorded. Statistical analysis was performed using SAS version 9.4.Results:A total of 396 patients were included for analysis, in which 330 (83.3%) patients received TCZ combined with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs), and 16.7%(66/396) received TCZ monotherapy. At baseline, TCZ was initiated in 56.6%(224/396) and 9.6%(38/396) of patients after failure of DMARDs and other biological agents (bDMARDs) respectively. During the 6-month follow-up period, the mean frequency of TCZ administration was (3.7±1.6), the mean TCZ dosage was (7.4±1.2) mg/kg, and the mean interval between doses was (40±13) days. 120(25.8%) patients were on TCZ treatment at the end of the study. Improvements in disease activity, systemic symptoms and patient report outcomes were observed at the end of the study. 22.7%(90/396) patients experienced at least one treatment related adverse event, and 8 patients experienced at least one serious adverse event.Conclusion:This study demonstrates that TCZ treatment is effective in patients with RA when being treated for 6 months with an acceptable safety profile. The duration of TCZ treatment needs to be extended.