Effects of dietary niacinamide and CP concentrations on the nitrogen excretion, growth performance, and meat quality of pigs.

Reducing the dietary CP concentration in the formulation of low-protein diets without adverse effects on animal growth performance and meat quality remains challenging. In this study, we investigated the effects of nicotinamide (NAM) on the nitrogen excretion, growth performance, and meat quality of growing-finishing pigs fed low-protein diets. To measure the nitrogen balance, we conducted two trials: in nitrogen balance trial 1, four crossbred (Duroc × Landrace × Large White) barrows (40 ± 0.5 kg BW) were used in a 4 × 4 Latin square design with four diets and periods. The diets consisted of a basal diet + 30 mg/kg NAM (a control dose), basal diet + 90 mg/kg NAM, basal diet + 210 mg/kg NAM, and basal diet + 360 mg/kg NAM. In nitrogen balance trial 2, another four barrows (40 ± 0.5 kg BW) were used in a 4 × 4 Latin square design. The diets consisted of a basal diet + including 30 mg/kg NAM (control), basal diet + 360 mg/kg NAM, low-protein diet + 30 mg/kg NAM, and low-protein diet + 360 mg/kg NAM. To measure growth performance, two trials were conducted. In growth performance trial 1, 40 barrows (37.0 ± 1.0 kg) were randomly allocated to one of four dietary treatments (n = 10 per group), whereas in growth performance trial 2, 300 barrows (41.4 ± 2.0 kg) were randomly allocated to one of four dietary treatments, with each dietary treatment conducted in five repetitions with 15 pigs each. The four diets in the two growth performance trials were similar to those in nitrogen balance trial 2. Supplementing the diet with 210 or 360 mg/kg NAM reduced urinary nitrogen excretion and total nitrogen excretion and increased nitrogen retention comparted with the control diet (P < 0.05). Compared with the control diet, the low-protein diet with 360 mg/kg NAM reduced faecal, urinary, and total nitrogen excretion (P < 0.05) without affecting nitrogen retention and average daily gain (P > 0.05). Pigs fed the low-protein diet with 360 mg/kg NAM showed a decreased intramuscular fat content in the longissimus thoracis muscle when compared with pigs fed the control diet (P > 0.05). Our results suggest NAM as a suitable dietary additive to reduce dietary CP concentration, maximise nitrogen retention and growth performance, and decrease fat deposition in pigs.

Utilizing integrating network pharmacological approaches to investigate the potential mechanism of Ma Xing Shi Gan Decoction in treating COVID-19.

Beginning in December 2019, coronavirus disease 2019 (COVID-19), due to 2019-nCoV infection, emerged in Wuhan and spread rapidly throughout China and even worldwide. Employing combined therapy of modern medicine and traditional Chinese medicine has been proposed, in which Ma Xing Shi Gan Decoction (MXSGD) was recommended as a basic prescription and applied widely in the clinical treatment of COVID-19. We investigated the underlying mechanism of MXSGD in treating COVID-19 utilizing the approaches of integrating network pharmacology. A total of 97 active ingredients of MXSGD were screened out, and 169 targets were predicted. The protein-protein interaction network exhibited hub targets of MXSGD, such as Heat shock protein 90, RAC-alpha serine/threonine-protein kinase, Transcription factor AP-1, Mitogen-activated protein kinase 1, Cellular tumor antigen p53, Vascular endothelial growth factor A, and Tumour necrosis factor. Gene Ontology functional enrichment analysis demonstrated that the biological processes altered within the body after taking MXSGD were closely related to the regulation of such processes as the acute inflammatory response, chemokine production, vascular permeability, response to oxygen radicals, oxidative stress-induced apoptosis, T cell differentiation involved in the immune response, immunoglobulin secretion, and extracellular matrix disassembly. KEGG enrichment analysis indicated that the targets of MXSGD were significantly enriched in inflammation-related pathways, immunomodulation-related pathways, and viral infection-related pathways. The therapeutic mechanisms of MXSGD on COVID-19 may primarily involve the following effects: reducing inflammation, suppressing cytokine storm, protecting the pulmonary alveolar-capillary barrier, alleviating pulmonary edema, regulating the immune response, and decreasing fever.

First Report of Tobacco curly shoot virus Infecting Pepper in China.

In recent years, whitefly-transmitted begomovirues (family Geminiviridae) have caused severe leaf curl disease on tobacco and tomato in southern China, but have not been found on pepper. In August 2009, pepper plants (Capsicum frutescens) grown in the field in Panzhihua City of Sichuan Province (southwestern China), from where the occurrence of begomoviruses has not been reported previously, showed stunting, leaf yellowing, and mild curling symptoms. To identify possible begomoviruses, total DNA was extracted from three infected pepper plants (SC117, SC118, and SC119) with typical symptoms. Using degenerate primer pair PA/PB specific for members of the genus Begomovirus (2), a 500-bp DNA fragment covering parts of the intergenic region and V2 gene of the genome of begomoviruses was amplified from all samples. No amplification was observed from healthy plant extracts. The PCR product from SC118 was cloned and two clones were chosen to be sequenced. Alignment of the partial DNA sequences revealed that the cloned products from isolate SC118 were nearly identical (98.5%) and most closely related to Tobacco curly shoot virus isolate Y35 (TbCSV-[China:Yunnan 35:2001]; Accession No. AJ420318) (96.9 and 97.3% identity, respectively). Therefore, the entire genome of isolate SC118 was sequenced. Overlap primers TbCSV-F(5'-CCGCCGTCTCAACTTCGACAG-3') and TbCSV-R(5'-ATCTGCTGGTCGCTTCGACAT-3') were designed to amplify the full-length genome of SC118. The complete genome sequence of SC118 was determined to be 2,746 nucleotides (Accession No. GU001879) long, with two open reading frames (ORFs) in the virion-sense strand and four ORFs in the complementary-sense strand, typical of the Old World begomoviruses. A comparison with other reported sequences of begomoviruses shows that the genome of SC118 shares the highest nucleotide sequence identity (99.7%) with TbCSV-[China:Yunnan 35:2001]. When PCR was used to detect TbCSV from the other two isolates (SC117 and SC119) with TbCSV specific primer pair Y35F1 and Y35+10R (4), which amplified the fragment covering the whole C2 and C3 genes and the partial C1 and V1 genes of the genome of TbCSV, an amplicon of approximately 1.0 kb was obtained from all samples. To determine whether a satellite molecule was associated with the three virus isolates, a universal betasatellite abutting primer pair (beta01 and beta02) was used (1). No amplification product was detected. In previous studies, it was demonstrated that only 11 isolates were associated with betasatellites among 39 TbCSV-infected, field-collected samples (3), and betasatellites could be associated with noncognate begomoviruses (4). Therefore, the three isolates examined in this study are too few to come to a conclusion that betasatellites are not associated with TbCSV infection of pepper plants. A detailed search for the presence of betasatellites needs to be conducted to draw a definitive conclusion. The above results confirmed that samples SC117, SC118, and SC119 were infected by TbCSV. To our knowledge, this is the first report of TbCSV on pepper in China. References: (1) R. W. Briddon et al. Mol. Biotechnol. 20:317, 2002. (2) D. Deng et al. Ann. Appl. Biol. 125:327, 1994. (3) Z. Li et al. Phytopathology 95:902, 2005. (4) L. Qing et al. Phytopathology 99:716, 2009.

Urine levels of aluminum after drinking tea.

A microwave-assisted acid digestion procedure coupled with a graphite furnace atomic absorption method has been applied in the determination of aluminum (Al) in urine to verify the correlation of free forms of Al in tea infusions and urinary excretion of Al. Significant urinary Al excretion has been found in 24-h urine of four volunteers after tea drinking. However, the difference in amount of Al excretion in urine between the consumption of Oolong (black tea) and Long-Jin (green tea), each of them with unique Al contents and species, was not significant. These findings indicated that the high levels of free Al species in tea infusions did not result in significant change in urinary excretion of the metal, possibly owing to the transformation by ligands present in food and the gastrointestinal tract (GIT). However, it could not be assumed that there was no big difference in absorption of the metal in the human body if fractions of consumed Al retained in the body or excreted by bile or feces were considered.

[Contraction stimulates incorporation of 3H-leucine and cell growth in cultured neonatal rat ventricular myocytes].

To determine whether contraction could influence cell growth, the rate of protein synthesis (3H-leucine incorporation) and cell diameter and volume were measured in cultured neonatal rat cardiac myocytes beating spontaneously or arrested by high potassium. In medium supplemented with 10% calf serum, the 3H-leucine incorporation for 24 h in contracting myocytes (CMC) was significantly higher by 14.2% than that in quiescent myocytes (QMC), i.e. 1,229 +/- 29 cpm/10(5) cells vs. 1,076 +/- 60 cpm/10(5) cells (P < 0.01, n = 5 for each group). The cell diameter and cell volume in QMC group were respectively 15.14 +/- 0.42 microns and 1,842 +/- 123 microns3, while in the CMC group the corresponding figures reached to 16.82 +/- 0.64 microns3 and 2,495 +/- 210 microns3, increased by 11.1% and 35.5% respectively (P < 0.01, n = 6 for each group). With prolongation of culture time, the differences in these parameters between CMC and QMC became even more significant. In all these experiments, there was no significant difference in cell number between the two groups (P > 0.05). It is concluded that contraction per se can accelerate protein synthesis and cell growth in neonatal rat ventricular myocardium.