Diagnostic accuracy of autoverification and guidance system for COVID-19 RT-PCR results

Background: To date, most countries worldwide have declared that the pandemic of COVID-19 is over, while the WHO has not officially ended the COVID-19 pandemic, and China still insists on the personalized dynamic COVID-free policy. Large-scale nucleic acid testing in Chinese communities and the manual interpretation for SARS-CoV-2 nucleic acid detection results pose a huge challenge for labour, quality and turnaround time (TAT) requirements. To solve this specific issue while increase the efficiency and accuracy of interpretation, we created an autoverification and guidance system (AGS) that can automatically interpret and report the COVID-19 reverse transcriptase-polymerase chain reaction (RT-PCR) results relaying on computer-based autoverification procedure and then validated its performance in real-world environments. This would be conductive to transmission risk prediction, COVID-19 prevention and control and timely medical treatment for positive patients in the context of the predictive, preventive and personalized medicine (PPPM). Methods: A diagnostic accuracy test was conducted with 380,693 participants from two COVID-19 test sites in China, the Hong Kong Hybribio Medical Laboratory (n = 266,035) and the mobile medical shelter at a Shanghai airport (n = 114,658). These participants underwent SARS-CoV-2 RT-PCR from March 28 to April 10, 2022. All RT-PCR results were interpreted by laboratorians and by using AGS simultaneously. Considering the manual interpretation as gold standard, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were applied to evaluate the diagnostic value of the AGS on the interpretation of RT-PCR results. Results: Among the 266,035 samples in Hong Kong, there were 16,356 (6.15%) positive, 231,073 (86.86%) negative, 18,606 (6.99%) indefinite, 231,073 (86.86%, negative) no retest required and 34,962 (13.14%, positive and indefinite) retest required; the 114,658 samples in Shanghai consisted of 76 (0.07%) positive, 109,956 (95.90%) negative, 4626 (4.03%) indefinite, 109,956 (95.90%, negative) no retest required and 4702 (4.10%, positive and indefinite) retest required. Compared to the fashioned manual interpretation, the AGS is a procedure of high accuracy [99.96% (95%CI, 99.95–99.97%) in Hong Kong and 100% (95%CI, 100–100%) in Shanghai] with perfect sensitivity [99.98% (95%CI, 99.97–99.98%) in Hong Kong and 100% (95%CI, 100–100%) in Shanghai], specificity [99.87% (95%CI, 99.82–99.90%) in Hong Kong and 100% (95%CI, 99.92–100%) in Shanghai], PPV [99.98% (95%CI, 99.97–99.99%) in Hong Kong and 100% (95%CI, 99.99–100%) in Shanghai] and NPV [99.85% (95%CI, 99.80–99.88%) in Hong Kong and 100% (95%CI, 99.90–100%) in Shanghai]. The need for manual interpretation of total samples was dramatically reduced from 100% to 13.1% and the interpretation time fell from 53 h to 26 min in Hong Kong; while the manual interpretation of total samples was decreased from 100% to 4.1% and the interpretation time dropped from 20 h to 16 min at Shanghai. Conclusions: The AGS is a procedure of high accuracy and significantly relieves both labour and time from the challenge of large-scale screening of SARS-CoV-2 using RT-PCR. It should be recommended as a powerful screening, diagnostic and predictive system for SARS-CoV-2 to contribute timely the ending of the COVID-19 pandemic following the concept of PPPM

Comparing the potential of Bacillus amyloliquefaciens CGMCC18230 with antimicrobial growth promoters for growth performance, bone development, expression of phosphorus transporters, and excreta microbiome in broiler chickens.

peer reviewedBone health of broiler chickens is essential for welfare and production. In this study, the probiotic Bacillus amyloliquefaciens (BA) CGMCC18230 was compared with antimicrobial growth promoters (AGPs) for its ability to promote growth and bone health. To address this, a total of 180 Arbor Acres (AA) 1-day-old, male, broiler chicks were randomly allocated into 3 treatment groups, with 6 replicates, containing 10 chicks in each replicate. The treatment groups were: control group (CON) fed a corn-soybean based diet; BA treatment group fed the basal diet supplemented with 2.5 × 1010 CFU/kg BA CGMCC18230; AGPs treatment group was fed the basal diet containing the antibiotics aureomycin (75 mg/kg), flavomycin (5 mg/kg) and kitasamycin (20 mg/kg). Over the 42 d experiment, broilers fed BA and AGPs diets both had higher BW, and the ADG was significantly (P < 0.05) higher than that of the CON group both in the grower phase (22-42 d) and overall. Moreover, with BA birds had higher (P < 0.05) serum concentrations of phosphorus (P, day 42) and alkaline phosphatase (ALP, days 21 and 42). Conversely, the content of P in excreta decreased significantly (P < 0.05) on days 21 and 42. Tibia bone mineralization was improved in BA, and the mRNA of P transport related genes PiT-1,2 in the duodenum and jejunum were significantly up-regulated in the BA group than in the CON group (P < 0.05). 16S rRNA gene sequencing revealed that dietary BA supplementation increased the relative abundance of butyrate-producing bacteria (Ruminococcaceae) and polyamine-producing bacteria (Akkermansia and Alistipes), which had a positive effect on bone development. These data show that dietary supplementation of BA CGMCC18320 improves broiler growth performance and bone health similar to supplementation with AGPs through up-regulation of intestinal P transporters, microbial modulation and increase P retention. However, no significant influence of BA CGMCC18320 supplementation on the retention of Ca was found

Differential Protein Expression in Honeybee (Apis mellifera L.) Larvae: Underlying Caste Differentiation

Honeybee (Apis mellifera) exhibits divisions in both morphology and reproduction. The queen is larger in size and fully developed sexually, while the worker bees are smaller in size and nearly infertile. To better understand the specific time and underlying molecular mechanisms of caste differentiation, the proteomic profiles of larvae intended to grow into queen and worker castes were compared at 72 and 120 hours using two dimensional electrophoresis (2-DE), network, enrichment and quantitative PCR analysis. There were significant differences in protein expression between the two larvae castes at 72 and 120 hours, suggesting the queen and the worker larvae have already decided their fate before 72 hours. Specifically, at 72 hours, queen intended larvae over-expressed transketolase, aldehyde reductase, and enolase proteins which are involved in carbohydrate metabolism and energy production, imaginal disc growth factor 4 which is a developmental related protein, long-chain-fatty-acid CoA ligase and proteasome subunit alpha type 5 which metabolize fatty and amino acids, while worker intended larvae over-expressed ATP synthase beta subunit, aldehyde dehydrogenase, thioredoxin peroxidase 1 and peroxiredoxin 2540, lethal (2) 37 and 14-3-3 protein epsilon, fatty acid binding protein, and translational controlled tumor protein. This differential protein expression between the two caste intended larvae was more pronounced at 120 hours, with particular significant differences in proteins associated with carbohydrate metabolism and energy production. Functional enrichment analysis suggests that carbohydrate metabolism and energy production and anti-oxidation proteins play major roles in the formation of caste divergence. The constructed network and validated gene expression identified target proteins for further functional study. This new finding is in contrast to the existing notion that 72 hour old larvae has bipotential and can develop into either queen or worker based on epigenetics and can help us to gain new insight into the time of departure as well as caste trajectory influencing elements at the molecular level

Isolation and characterization of two Acinetobacter species able to degrade 3-methylindole.

3-Methylindole (3MI) or Skatole is a volatile lipophilic organic compound produced by anoxic metabolism of L-tryptophan and associated with animal farming and industrial processing wastes. Pure cultures of bacteria capable of utilizing 3MI were isolated from chicken manure using enrichment culture techniques. The bacteria were identified as Acinetobacter toweneri NTA1-2A and Acinetobacter guillouiae TAT1-6A, based on 16S rDNA gene amplicon sequence data. The optimal temperature and pH for degradation of 3MI were established using single factor experiments. Strain tolerance was assessed over a range of initial concentrations of 3MI, and the effects of initial concentration on subsequent microbial 3MI degradation were also measured. During the degradation experiment, concentrations of 3MI were quantified by reverse-phase high-performance liquid chromatography (HPLC). The strains were capable of degrade initial concentrations of 3MI ranging from 65-200 mg/L. The degradation efficiency was >85% in 6 days for both strains when the initial concentration is less than 200 mg/L. The strains were tested for enzymatic activity using 65 mg/L 3MI. The enzyme extracts of NTA1-2A and TAT1-6A from the 3MI medium degraded 71.46% and 60.71% of 3MI respectively, but no appreciable change in 3MI concentration in the control group was witnessed. Our experiment revealed betaine and choline were identified as 3MI degradation metabolites by both strains while nitroso-pyrrolidine and beta-alaninebetaine formed by NTA1-2A and TAT1-6A strains respectively. The NTA1-2A and TAT1-6A strains removed 84.32% and 81.39% 3MI respectively from chicken manure during fermentation in 8 days and showed a statistically significant difference (P < 0.05) compared with the control group. The optimum temperature and pH were 31°C and 6 respectively, for 3MI degradation by A. toweneri NTA1-2A and A. guillouiae TAT1-6A. We concluded that A. toweneri NTA1-2A and A. guillouiae TAT1-6A are potential strains of interest to degrade 3MI and control odorant in poultry and other livestock industries

Phase Diagram for the Na2SO4-NaOH-H2O System and Na2SO4 Solubility in Sodium Aluminate Solution with Caustic Ratios of 12 and 15 at 80 degrees C

The phase diagram for the Na2SO4-NaOH-H2O system and solubility data for Na2SO4 in sodium aluminate solution with Na2O to Al2O3 ratios (caustic ratios) of 12 and 15 were studied in the full alkali concentration region at 80 degrees C. The contents of Al and Na in the solution were analyzed by means of inductively coupled atomic plasma emission spectrometry (ICP-OES). The sulfur content was determined using ion chromatography (IC) and the ethylenediaminetetraacetic acid (EDTA) volumetric method. The phases of the equilibrium solids were identified via X-ray diffraction (XRD) as well as Schreinemaker's method. The results showed that the Na2SO4 solubility declines as the concentration of NaOH in the ternary system increases. At a NaOH concentration exceeding 32.96 % (mass percent), the Na2SO4 solubility is lower than 1.13 %. For this system, the corresponding equilibrium solid phase was identified as anhydrous sodium sulfate (Na2SO4) and sodium hydroxide (NaOH) The Na2SO4 solubility in the quaternary system approximates the values obtained in the Na2SO4-NaOH-H2O system. At NaOH concentrations higher than 30.68 % and 30.76 % the Na2SO4 solubility values in the sodium aluminate solution with caustic ratios of 12 and 15 are lower than 1.03 % and 1.05 %, respectively

Dietary 5-aminolevulinic acid supplementation improves growth performance, nutrient utilisation, iron status and antioxidant capacity of broilers

This study aimed to investigate the effects of dietary supplementation with 5-aminolevulinic acid (5-ALA) on growth performance, blood parameters, iron status, nutrient digestibility, and antioxidant capacity in broilers. A total of 600 one-day-old Arbour Acres broilers were distributed into 5 groups with 6 replicates of 20 birds by a completely randomised design. The birds in the 5 groups were fed the basal diets with 0, 15, 30, 45, and 60 mg/kg 5-ALA, respectively. Dietary supplementation with 60 mg/kg 5-ALA significantly reduced the feed to gain ratio during days 1–21 and days 22–42. Moreover, compared with the control group, dietary supplementation with 30 mg/kg 5-ALA elevated haemoglobin concentrations during days 1–21. Furthermore, dietary supplementation with 45 and 60 mg/kg 5-ALA increased the digestibility of crude protein and decreased serum uric acid levels. At 21 days of age, dietary supplementation with 45 and 60 mg/kg 5-ALA increased liver catalase activity and decreased liver malondialdehyde concentrations, and upregulated the liver mRNA expression of ferritin light chain and nuclear factor erythroid 2-related 2. In addition, the liver mRNA expression of haem oxygenase-1 and divalent metal transporter were upregulated in the 60 mg/kg 5-ALA supplementation group, while the liver mRNA expression of Kelch-like ECH-associated protein 1 was decreased in the 5-ALA supplementation groups. In conclusion, dietary supplementation with 60 mg/kg 5-ALA improved the growth performance, nutrient digestibility, iron status and antioxidant capacity of 21-d-old broilers.Highlights Addition of 60 mg/kg 5-ALA to broiler diets reduced the feed to gain ratio. Addition of 45 and 60 mg/kg 5-ALA to broiler diets improved crude protein digestibility and decreased serum uric acid levels. 5-ALA exhibited antioxidant properties by enhancing the Nrf2 and HO-1 expressio

Augmentation of Performance, Carcass Trait, Biochemical Profile and Lipid Metabolism Concerning the Use of Organic Acidifier in Broiler Chickens

This study aimed to disclose the effects of a new compound organic acidifier mixing with L-malic acid and L-lactic acid on broiler production. A total of 1000 1-day-old Arbor acres broiler chicks were randomly divided into two treatments of 10 replicates each, with 50 birds per replicate. The feeding trial lasted for 42 days. The treatment group was offered 0.8% of the acidifier based on the control. The growth performance of the broiler chickens was improved by treatment. The broiler chickens in treatment had lower triglyceride but higher high-density lipoprotein content in serum. Superoxide dismutase activity, total antioxidant capacity and the concentrations of immunoglobulin A, complement 3 and lysozyme were increased in the serum of the broiler chickens, while the concentrations of interleukin-2 and tumor necrosis factor-α in the mucosa of jejunum were decreased by treatment. The expressions of AMPK, CD36, FABP1, MTTP and PPARα were increased but expressions of APOB100 and PCSK9 were decreased by treatment. In conclusion, the acidifier was effective at promoting broiler production, which was probably through the improved immunity, antioxidant and hepatic lipid metabolism capacities. The acidifier may be accelerating lipid metabolism in broiler chicken liver through regulating the expression of the genes related to fat metabolism