Small object intelligent detection method based on adaptive recursive feature pyramid.

As we all know, YOLOv4 can achieve excellent detection performance in object detection and has been effectively applied in many fields. However, the inconsistency of scale features affects the prediction accuracy of the path aggregation network (PANet) in YOLOv4 for small objects, resulting in low detection accuracy. This paper presents YOLOv4, which uses an adaptive recursive path aggregation network (AR-PANet) to improve the detection accuracy of small objects.

Effects of prehospital management in out-of-hospital cardiac arrest: advanced airway and adrenaline administration.

Background: There is uncertainty about the best approaches for advanced airway management (AAM) and the effectiveness of adrenaline treatments in Out-of-hospital cardiac arrest (OHCA). This study aimed to evaluate whether AAM and adrenaline administration provided by Emergency Medical Service (EMS) can improve the outcomes of OHCA.

Methods: This study was a prospective analysis of collected data based on OHCA adult patients treated by the EMS in China from January 2019 to December 2020.

Serosurvey of Avian metapneumovirus, Orithobacterium rhinotracheale, and Chlamydia psittaci and Their Potential Association with Avian Airsacculitis.

Seasonal outbreaks of airsacculitis in China's poultry cause great economic losses annually. This study tried to unveil the potential role of Avian metapneumovirus (AMPV), Ornithobacterium rhinotracheale (ORT) and Chlamydia psittaci (CPS) in avian airsacculitis. A serological investigation of 673 breeder chickens and a case-controlled study of 430 birds were undertaken.

PEG-modulated column chromatography for purification of recombinant adeno-associated virus serotype 9.

Column chromatography has been described for purification of recombinant adeno-associated viral vectors (rAAV) serotypes 1, 2, 5, 6 and 8. Some of these purification processes have been used in manufacturing pre-clinical grade and clinical grade rAAV vectors. Recently, recombinant AAV9 has been reported to be highly efficient in transducing cardiac muscle in animal models.

Systemic elimination of de novo capsid protein synthesis from replication-competent AAV contamination in the liver.

The capsid protein synthesis in targeted tissues resulting from residual contaminating replication-competent adeno-associated virus particles (rcAAV) remains a concern for hazardous immune responses that shut down the factor IX expression in the hemophilia B clinical trial. To systematically reduce/eliminate the effects of potential contaminating rcAAV particles, we designed a novel adeno-associated virus (AAV) helper (pH22mir) with a microRNA binding cassette containing multiple copies of liver-specific (hsa-mir-122) and hematopoietic-specific (has-mir-142-3p) sequences to specifically control cap gene expression. In 293 cells, the rep and cap gene from pH22mir functioned similarly to that of conventional helper pH22.

[Genetic diversity of AVR-pita alleles of rice blast fungus Magnaporthe grisea].

Rice blast, caused by fungus Magnaporthe grisea, is one of the most serious diseases of rice throughout the world and is also a classical system in which avirulence (AVR) genes in the pathogen show a functional correspondence with particular resistance (R) genes in rice. The interaction between AVR-pita gene in Magnaporthe grsiea and Pi-ta gene in rice is a classical gene-for-gene system. The genetic diversity of AVR-pita alleles was showed by 44 isolates from the fields in Sichuan and Chongqing.

Undetectable transcription of cap in a clinical AAV vector: implications for preformed capsid in immune responses.

In a gene therapy clinical trial for hemophilia B, adeno-associated virus 2 (AAV2) capsid-specific CD8(+) T cells were previously implicated in the elimination of vector-transduced hepatocytes, resulting in loss of human factor IX (hFIX) transgene expression. To test the hypothesis that expression of AAV2 cap DNA impurities in the AAV2-hFIX vector was the source of epitopes presented on transduced cells, transcription of cap was assessed by quantitative reverse transcription-PCR (Q-RT-PCR) following transduction of target cells with the vector used in the clinical trial. Transcriptional profiling was also performed for residual Amp(R), and adenovirus E2A and E4.

Clinical manifestations and arsenic methylation after a rare subacute arsenic poisoning accident.

One hundred and four workers ingested excessive levels of arsenic in an accident caused by leakage of pipeline in a copper-smelting factory. Clinical examinations were performed by physicians in a local hospital. Excreted urinary arsenic species were determined by cold trap hydride generation atomic absorption spectrometry.

Reversal of blindness in animal models of leber congenital amaurosis using optimized AAV2-mediated gene transfer.

We evaluated the safety and efficacy of an optimized adeno-associated virus (AAV; AAV2.RPE65) in animal models of the RPE65 form of Leber congenital amaurosis (LCA). Protein expression was optimized by addition of a modified Kozak sequence at the translational start site of hRPE65.

Separation of adeno-associated virus type 2 empty particles from genome containing vectors by anion-exchange column chromatography.

Adeno-associated virus (AAV) empty capsids typically co-purify with genome containing AAV2 vectors purified by column chromatography. This study describes a method to remove empty capsids from genome containing vector particles by anion exchange chromatography. The separation is based on the slightly less anionic character of empty particles compared to vectors.

Identification of factors that contribute to recombinant AAV2 particle aggregation and methods to prevent its occurrence during vector purification and formulation.

Aggregation of recombinant AAV2 results in reduced yield during purification and may have deleterious effects on vector transduction efficiency, biodistribution and immunogenicity following in vivo administration. Studies to elucidate the mechanism of vector aggregation and methods to prevent its occurrence are reported. In excipient screening studies, the sugars sorbitol, sucrose, mannitol, trehalose, or glycerol at concentrations of up to 5% (w/v), or surfactants Tween 80 or Pluronic F68, did not prevent aggregation.

Recombinant adeno-associated virus: formulation challenges and strategies for a gene therapy vector.

Recombinant adeno-associated virus (AAV)-based vectors capable of expressing therapeutic gene products in vivo have shown significant promise for human gene therapy. One challenge facing the field is the development of vector formulations to achieve optimal vector safety, stability and efficacy. Formulation challenges for AAV vectors can be divided into those relating to maintaining vector activity during purification and storage, and those relating to efficient target tissue transduction in vivo.