This study aims to establish a method for counting the viral particles in adenovirus vector-based vaccines. Nano-flow cytometry was employed to analyze the viral particles in adenovirus-based vector vaccines at the single-particle level. Monodisperse silica nanoparticles with a refractive index close to that of the virus were selected as the particle size standard to calculate the viral particle size, which was then compared with the results obtained from transmission electron microscopy (TEM) to determine the gating strategy. Subsequently, a particle count standard was employed to calculate the viral particle concentration. The established method demonstrated good linearity, accuracy, precision, and specificity. The results of determined viral particle concentration showed a good correlation with the infectious titer. Compared with the conventional OD₂₆₀ method, nano-flow cytometry can directly measure the viral particle concentration and indicate whether the sample has been disassembled according to changes in viral particle concentration and size, thus more accurately reflecting the actual infectious potency of the sample. The novel quantification method established in this study is capable of indicating the efficacy of adenovirus vector-based vaccines and provides effective technical support for the quality control of such products.
Adenoviridae/genetics* ; Genetic Vectors ; Flow Cytometry/methods* ; Virion/isolation & purification* ; Particle Size ; Nanoparticles ; Viral Vaccines

Abstract: Objective To analyze the epidemiological characteristics of reported cases of dengue fever in mainland China from 2019 to 2023 and provide a scientific basis for dengue prevention and control efforts. Methods The temporal, spatial, and population distribution characteristics, as well as the trends of dengue fever cases reported in the National Notifiable Disease Reporting System (NNDRS) of China were analyzed using software such as Joinpoint regression, SaTScan, and ArcGIS. Results From 2019 to 2023, a total of 43 095 cases were reported in China, with an average incidence rate of 61/100 000. The annual reported incidence rate fluctuated significantly (AAPC=-3.16%, 95%CI:-54.16%-91.47%), mainly concentrated in 2019 and 2023, accounting for 96.83% of the total reported cases over the past five years. All age groups were susceptible to the disease, with the 30 to <40 age group comprising 22.6% of cases. Cases were reported throughout the year, with a rapid increase starting in June and a peak period concentrated between August and October (n=34 780, RR=12.44, LLR=29 262.52, P<0.05). The epidemic was primarily characterized by imported cases leading to autochthonous transmission, with the majority of imported cases originating from Southeast Asia (86.56%), particularly from Cambodia (46.11%, 3 284 cases) and Myanmar (25.99%, 1 851 cases). The epidemic characteristics varied significantly across different years, with high risks of autochthonous transmission epidemics in Southwest, South, and Southeast China. High-risk local transmission were mainly distributed in Yunnan and Guangdong. The duration of the peak period of the epidemic was affected by the timeliness of early detection of local transmission, and the peak value of the epidemic was related to the effectiveness of prevention and control measures. The scale of the epidemic was influenced by the pressure of by cross-border transmission and the ability to implement local measures for dengue prevention and control. Conclusions With the increasing trend of global dengue transmission, the risk of autochthonous transmission of dengue in China is rising. It is recommended to strengthen proactive early outbreak surveillance, along with well preparation of personnel, technology, and resources for dengue prevention and control.According to autochthonous conditions, reasonable management and risk assessment of cross-border travelers should be explored to effectively.

Objective: To report the experience on the multi-disciplinary management of metastatic renal cell (mRCC) patients in a single center. Methods: Data of 168 mRCC patients treated by multi-disciplinary team (MDT) at Sun Yat-sen University Cancer Center from December 2007 to February 2019 was retrospectively analyzed.Three treatment groups were identified, including 76 patients with 55 males and 21 females, received anti-angiogenic agents alone (Group A), 66 patients with 55 males and 11 males, received anti-angiogenic agents plus local therapy (Group B)and 26 patients, with 19 males and 7 females, received anti-angiogenic agents plus immunotherapy and local therapy (Group C). The Sunitinib, Sorafenib, Axitinib were chosen for the TKI. The Pembrolizumab was used for immunotherapy. The stereotactic body radiation therapy and surgical excision were considered as the local therapy. The study aims to compare the age, gender, IMDC score, pathology, nbephrectomy, adverse events, progression-free survival and overall survival (OS). Results: Of all patients, the median follow-up duration was 23 months (ranging 6-117 cmonths). The PFS was 18.3 months and median OS was 33.5 months. The 2 years and 5 years survival rate was 66% and 35%, respectively. The median OS of Group A, B and C were 29.8 months, 44.6 months and not reached. 2y-OS was 58%, 67% and 89%, while 5y-OS 12%, 46% and 57%.There was no difference in age, gender, IMDC score, pathology, synchronous metastases or nephterectomy between the three groups. The prognostic result in TKI based combination therapy was superior to TKI therapy alone, which the 5y-OS was 51% and 11%, respectively. The prognostic result in group C's moderate-high risk mRCC patients was superior to group A and B. The median OS in TKI+ DC and CIK+ Pembrolizumab was 49.1 months and 53.1 months. On univariate analyses, IMDC score, nephrectomy and treatment group was associated with OS (P<0.05). On multivariate analyses, treatment group, nephrectomy was associated with OS (P<0.05). The risk of death of Group C decreased about 60% [HR 0.39 (0.17, 0.89), P=0.026]. 78 (46.4%) patients on TKI alone and 16 (61.5%) patients treated with TKI plus immunotherapy had Grade 3 or 4 adverse events. 16 (20.3%) patients had Clavien Ⅲ-Ⅳ toxicity after surgical procedures. 6 (5.7%) patients had Grade 3 toxiciy after SBRT. Conclusions Patients treated with combined therapy had better survival than those treated with anti-angiogenic agents alone. MDT approach could bring survival benefit to mRCC patients.

Objective:To evaluate the accuracy of the application of color Doppler sonography (CDS) and computer tomography angiography (CTA) in preoperative perforator identification and flap design and provide theoretical support for the restoration of oral maxillofacial defect with free superficial circumflex iliac artery perforator flap (SCIAPF). Methods: (1) Preoperative CDS and CTA techniques were performed to map the SCIA perforators of 29 adult patients diagnosed with malignant tumor in the oral maxillofacial head and neck regions. These patients were scheduled for concurrent reconstruction surgery. (2) A diagnostic test was designed to com-pare the CDS and CTA techniques. Results:(1) A total of 18 patients underwent flap preparation. SCIA was not found in one of the pa-tients during surgery, but was observed intra-operatively in the other 17 patients. The average SCIA diameter was 0.69 ± 0.20 mm. (2) The diagnostic test showed a CDS sensitivity of 75.0%, a CDS specificity of 82.4%, and an area under the ROC curve of 0.79. The CTA sensitivity was 75.0%, the specificity was 94.2%, and the area under the ROC curve was 0.85. The diameters measured by CDS and CTA were compared with the diameter measured intra-operatively. Significant differences were observed among the three diame-ters (P<0.05). The average diameter measured by CDS was 0.84 ± 0.14 mm. The average diameter measured by CTA was 1.01 ± 0.19 mm. Conclusion:CDS and CTA are relatively reliable technologies for preoperative detection of perforator vessel. The use of CDS and CTA technology mapping for SCIAPF can provide accurate information about the perforator, including the position of the perforator and the relationship between the peripheral tissues and the caliber of the vessel.

Objective:To assess the anatomy of superficial circumflex iliac artery perforator (SCIP) and its feasibility for tongue re-construction after tumor resection. Methods:From January 2014 to January 2015, a total of 15 patients with oral maxillofacial defects underwent SCIP flap surgery. Perforator identification and SCIA course were performed intra-operatively. The relationships among the SCIA, deep circumflex iliac artery (DCIA), and superficial inferior epigastric artery (SIEA) were determined intra-operatively. Surgical procedures, measurement of vessel's caliber and pedicle's length, SCIP flap anatomy, and their outcomes were described. Results:Flap mean thickness was approximately 1.2±0.3 cm. The mean diameter of the SCIA was 0.7±0.2 cm, and that of the superficial circumflex iliac vein was 1.2±0.2 cm. The relationships among SCIA, DCIA, and SIEA were described and subdivided into typeⅠ(8/15), typeⅡ(2/15), typeⅢ(2/15), typeⅣ(2/15), and typeⅤ(1/15) in intra-operative dissection. The flap sizes were in the range from 6 cm × 4.5 cm to 11 cm × 10 cm. A total of 14 SCIP flaps survived, and 1 SCIP flap underwent necrosis. Conclusion:The SCIP flap is a reliable, thin, and pliable flap with long vascular pedicles and hidden donor site morbidity. Its texture is a perfect match for tongue defect reconstruc-tion.