Nanobodies(Nb)have become novel probes for PET imaging instead of traditional antibodies,which have broad application prospects due to advantages of small molecular weight,strong stability and permeability,passing through the blood-brain barrier and low immunogenicity.The research progresses of structural characteristics of Nb,labeling methods of positron isotopes and application of labeled products in PET imaging were reviewed in this article.

Objective:To investigate the role and molecular mechanisms of signal transducer and activator of tran-scription 3(STAT3)in the paraventricular nucleus(PVN)of the hypothalamus in regulating body weight and energy metabolism in mice.Methods:AAV2/9-hSyn-Cre-EGFP virus was stereotactically injected into the PVN of STAT3Flox/Flox mice to conditionally knock out(CKO)STAT3 in the PVN.STAT3 expression was verified via immunoflu-orescence staining and Western blot.Body weight and temperature were monitored,glucose tolerance was assessed using glucose tolerance tests in mice,and morphological changes in the liver,interscapular brown adipose tissue(IBAT),in-guinal white adipose tissue(IWAT),and quadriceps muscle were evaluated via hematoxylin-eosin(HE)staining.RT-qPCR was used to measure mRNA levels of platelet-derived growth factor receptor α(PDGFRα),peroxisome prolifera-tor-activated receptor γ(PPARγ),hormone-sensitive lipase(HSL),and adipose triglyceride lipase(ATGL)in these tissues.Results:STAT3 protein expression in the PVN of CKO mice was significantly reduced,and the number of STAT3-positive neurons was also decreased.Compared to wild-type(WT)mice,CKO mice exhibited increased body weight,impaired thermogenesis in IBAT,and reduced glucose tolerance.HE staining revealed lipid droplet accumula-tion in hepatocytes of the liver,enlarged adipocytes with hypertrophic lipid droplets and leukocyte infiltration in adipose tissues,and intermuscular fat deposition in the quadriceps muscle.RT-qPCR analysis showed decreased mRNA levels of PDGFRα,HSL,and ATGL in the liver;upregulated PPARγ mRNA but downregulated HSL and ATGL mRNA in IBAT and IWAT;and reduced PPARγ and HSL mRNA levels in the quadriceps muscle of CKO mice.Conclusion:The STAT3 signaling pathway in the PVN is critical for maintaining systemic energy balance and serves as a key node in met-abolic regulation.

Acetabular fracture is a kind of intra-articular fracture with complicated anatomy and difficult treatment. The core of treatment lies in anatomic reduction and strong fixation. The low incidence and intricate anatomical structure present significant challenges for treatment of acetabular fractures. In recent years, significant progress has been made in the treatment of acetabular fractures, particularly in surgical approaches, robotic-assisted technology, the application of tranexamic acid, and treatment strategies for elderly patients, providing new therapeutic options. This article reviews the latest progress in acetabular fracture treatment research.

Objective:To investigate the application of time series models in forecasting pre-hospital emergency ambulance trips in Handan City and develop the LPro ensemble model for improved prediction accuracy to support emergency resource allocation.Methods:Pre-hospital emergency data from Handan Emergency Medical Command Center (2019-2023) were retrospectively analyzed. From 324 799 original records, 289 949 valid records were included after cleaning. The training set (2019-2022: 215 918 records) included 35 527 records in 2019, 52 015 in 2020, 61 836 in 2021, and 66 540 in 2022. The validation set (2023) contained 74 031 records. ARIMA, linear trend seasonal, exponential smoothing, and Prophet models were fitted to the training set. The LPro ensemble model was constructed using MAPE-based weighting (linear trend seasonal model: 0.38, Prophet: 0.62). Performance metrics included MAPE, RMSE, MAE, and R 2. Results:Data showed annual growth (compound annual growth rate 23.27%) and seasonal patterns (October peaks, February troughs). Ambulance dispatches increased annually with monthly cyclical patterns. For 2023 validation predictions: ARIMA (MAPE 8.76%, RMSE 619, MAE 491, R 2 0.4563), linear trend seasonal (MAPE 9.83%, RMSE 671, MAE 545, R 2 0.3608), Prophet (MAPE 8.43%, RMSE 562, MAE 503, R 2 0.5513), exponential smoothing (MAPE 8.08%, RMSE 643, MAE 410, R 2 0.4124). LPro model showed superior performance (MAPE 7.05%, RMSE 491, MAE 393, R 2 0.6570), with 16.37% lower MAPE, 12.63% lower RMSE, 21.87% lower MAE, and 19.17% higher R 2 versus Prophet. Conclusion:The LPro ensemble model substantially enhances prediction accuracy and reliability, offering scientific support for emergency resource optimization and dispatch scheduling in Handan City.

Objective:To investigate the role and molecular mechanisms of signal transducer and activator of tran-scription 3(STAT3)in the paraventricular nucleus(PVN)of the hypothalamus in regulating body weight and energy metabolism in mice.Methods:AAV2/9-hSyn-Cre-EGFP virus was stereotactically injected into the PVN of STAT3Flox/Flox mice to conditionally knock out(CKO)STAT3 in the PVN.STAT3 expression was verified via immunoflu-orescence staining and Western blot.Body weight and temperature were monitored,glucose tolerance was assessed using glucose tolerance tests in mice,and morphological changes in the liver,interscapular brown adipose tissue(IBAT),in-guinal white adipose tissue(IWAT),and quadriceps muscle were evaluated via hematoxylin-eosin(HE)staining.RT-qPCR was used to measure mRNA levels of platelet-derived growth factor receptor α(PDGFRα),peroxisome prolifera-tor-activated receptor γ(PPARγ),hormone-sensitive lipase(HSL),and adipose triglyceride lipase(ATGL)in these tissues.Results:STAT3 protein expression in the PVN of CKO mice was significantly reduced,and the number of STAT3-positive neurons was also decreased.Compared to wild-type(WT)mice,CKO mice exhibited increased body weight,impaired thermogenesis in IBAT,and reduced glucose tolerance.HE staining revealed lipid droplet accumula-tion in hepatocytes of the liver,enlarged adipocytes with hypertrophic lipid droplets and leukocyte infiltration in adipose tissues,and intermuscular fat deposition in the quadriceps muscle.RT-qPCR analysis showed decreased mRNA levels of PDGFRα,HSL,and ATGL in the liver;upregulated PPARγ mRNA but downregulated HSL and ATGL mRNA in IBAT and IWAT;and reduced PPARγ and HSL mRNA levels in the quadriceps muscle of CKO mice.Conclusion:The STAT3 signaling pathway in the PVN is critical for maintaining systemic energy balance and serves as a key node in met-abolic regulation.

Nanobodies(Nb)have become novel probes for PET imaging instead of traditional antibodies,which have broad application prospects due to advantages of small molecular weight,strong stability and permeability,passing through the blood-brain barrier and low immunogenicity.The research progresses of structural characteristics of Nb,labeling methods of positron isotopes and application of labeled products in PET imaging were reviewed in this article.

Objective To investigate the geographical distribution and seasonal fluctuations of visceral leishmaniasis vectors sandflies in Henan Province in 2023, so as to provide insights into the prevention and control of visceral leishmaniasis vectors. Methods A total of 23 counties (districts) were sampled from 18 cities of Henan Province from May to September, 2023 as sandfly surveillance sites, and sandflies were captured using human capture and light trapping methods. Following morphological identification, the changes in the sandfly density were calculated at different months and in different breeding habitats. Results A total of 406 light traps were set at sandfly surveillance sites in Henan Province from May to September, 2023, and a total of 3 137 female sandlies were captured, with an average density of 7.73 sandlies/(light·night). A total of 1 494 Phlebotomus chinensis sandflies were captured, including 1 222 female sandflies, with an average density of 3.01 sandflies/(light·night), and the highest density of P. chinensis was found in Gongyi City [17.00 sandflies/(light·night)]. A total of 5 544 sandflies were captured using the human capture method, including 230 P. chinensis, and the density of P. chinensis appeared a unimodal distribution, with a peak in early July [5.81 sandflies/(light·night)]. Among different breeding habitats, the highest P. chinensis density was detected in pigpens [4.50 sandflies/(light·night)]. Conclusions P. chinensis was predominantly distributed in hilly areas of northern and central-western Henan Province in 2023, and the sandfly density appeared a unimodal distribution. Intensified monitoring of visceral leishmaniasis vectors is recommended.

Objective To analyze the characteristics of visceral leishmaniasis cases in Henan Province, so as to provide insights into formulation of the visceral leishmaniasis control srtrategy. Methods All epidemiological data of reported visceral leishmaniasis cases in Henan Province from 2021 to 2023 were retrieved from the National Notifiable Disease Report Information Management System of Chinese Center for Disease Control and Prevention, and the epidemiological features and diagnosis of visceral leishmaniasis cases were descriptively analyzed. Results A total of 93 visceral leishmaniasis cases were reported in Henan Province from 2021 to 2023, with a male to female ratio of 2.58∶1, and including 2 imported cases from other provinces and 91 local cases. The number of visceral leishmaniasis cases peaked during the period between March and May, and between July and October. The reported visceral leishmaniasis cases had ages of 7 months to 74 years, with the largest number of cases found at ages of 0 to 9 years (26 cases, 27.96%), followed by at ages of 60 to 70 years (24 cases, 25.81%). Farmer (47 cases, 50.54%) and diaspora children (19 cases, 20.43%) were predominant occupations, and 91 local visceral leishmaniasis cases were found in 6 cities of Zhengzhou, Luoyang, Anyang, Hebi, Sanmenxia and Xuchang. The median duration from onset of visceral leishmaniasis to diagnosis was 20 days, and there were 25.81% (24/93) cases with 10 days and less duration from onset to diagnosis, 38.71% (36/93) cases receiving diagnosis at 11 to 30 days following onset, and 35.48% (33/93) cases receiving diagnosis for more than 30 days following onset. All cases were predominantly diagnosed in province- (60.00%) and city-level (28.89%) medical institutions. Conclusions The number of visceral leishmaniasis is on the rise in Henan Province, with a gradually expanding coverage. Intensified monitoring of visceral leishmaniasis cases, dogs, and vectors, dog management, sandflies control and improved individual protection are recommended to prevent the spread of visceral leishmaniasis.

Objective:To explore the clinical characteristics, diagnosis, treatment, and follow-up of multisystem inflammatory syndrome in children (MIS-C) related to SARS-CoV-2 Omicron variant infection.Methods:A retrospective analysis was conducted on clinical data of 11 children with MIS-C, who were admitted to the Department of Pediatrics of Peking University First Hospital from December 2022 to January 2023. Clinical characteristics, treatment, and follow-up of MIS-C were summarized in this study.Results:The 11 cases contained 7 boys and 4 girls, with an age of 4.4 (2.0, 5.5) years on admission. All the patients had fever, with a duration of 7(5, 9) days. Other clinical manifestations included rash in 7 cases, conjunctival hyperemia in 5 cases, red lips and raspberry tongue in 3 cases, lymphadenopathy in 3 cases, and swollen fingers and toes in 2 cases. There were 8 cases of digestive symptoms, 8 cases of respiratory symptoms, and 3 cases of nervous system symptoms. Eight patients had multi-system injuries, and one of them had shock presentation. All 11 patients were infected with SARS-CoV-2 Omicron BF.7 variant. The laboratory examination results showed that all cases had elevated inflammatory indicators, abnormal coagulation function and myocardial damage. Six patients had elevated white blood cell counts, 5 cases had liver function abnormalities, 3 cases had kidney function abnormalities, and 8 cases had coronary artery involvement. All 11 patients received anti-infection treatment, of which 3 cases received only 2 g/kg intravenous immunoglobulin (IVIG), while the remaining 8 cases received a combination of IVIG and 2 mg/(kg·d) methylprednisolone. Among the 8 cases with coronary artery disease, 6 cases received low molecular weight heparin anticoagulation therapy. All patients were followed up in 2 weeks after being discharged, and their inflammatory markers had returned to normal by that time. The 8 cases with coronary artery disease and 3 cases with pneumonia showed significant improvement or back to normal at the 4-week follow-up. All patients had no new complications or comorbidities during follow-up of more than 3 months.Conclusions:MIS-C may present with Kawasaki disease-like symptoms, with or without gastrointestinal, neurological, or respiratory symptoms. Elevated inflammatory markers, abnormal coagulation function, and cardiac injury contribute to the diagnosis of MIS-C. IVIG and methylprednisolone were the primary treatments for MIS-C, and a favorable short-term prognosis was observed during a follow-up period of more than 3 months.