Risk of Malnutrition in Hospitalized COVID-19 Patients: A Systematic Review and Meta-Analysis.

(1) Background: Studies have reported that COVID-19 may increase the risk of malnutrition among patients. However, the prevalence of such risk in hospitalized COVID-19 patients is uncertain due to the inconsistent use of assessment methods. (2) Methods: PubMed, Web of Science, and EMBASE were searched to identify studies on the nutritional status of hospitalized COVID-19 patients. A pooled prevalence of malnutrition risk evaluated by Nutrition Risk Score (NRS-2002) was obtained using a random effects model. Differences by study-level characteristics were examined by hospitalization setting, time of assessment, age, and country. Risk of bias was assessed using the Newcastle−Ottawa Scale. (3) Results: 53 studies from 17 countries were identified and summarized. A total of 17 studies using NRS-2002, including 3614 COVID-19 patients were included in the primary meta-analysis. The pooled prevalence of risk of malnutrition was significantly higher among ICU patients (92.2%, 95% CI: 85.9% to 96.8%) than among general ward patients (70.7%, 95% CI: 56.4% to 83.2%) (p = 0.002). No significant differences were found between age groups (≥65 vs. <65 years, p = 0.306) and countries (p = 0.893). (4) Conclusions: High risk of malnutrition is common and concerning in hospitalized patients with COVID-19, suggesting that malnutrition screening and nutritional support during hospitalization are needed.

A functional mutation associated with piglet diarrhea partially by regulating the transcription of porcine STAT3.

The present study aimed to search for functional mutations within the promoter of porcine STAT3 and to provide causative genetic variants associated with piglet diarrhea. We firstly confirmed that STAT3 expressed higher in the small intestine than in the spleen, stomach and large intestine of SPF piglets, respectively (P < 0.05). Then, 10 genetic variations in the porcine STAT3 promoter region was identified by direct sequencing. Among them, three mutations SNP1: g.-870 G>A, SNP2: g.-584 A>C and a 6-bp Indel in the promoter region that displayed significant differential transcriptional activities were identified. Association analyses showed that SNP1: g.-870 G>A was significantly associated with piglet diarrhea (P < 0.05) and the GG animals had lower diarrhea score than AA piglets (P < 0.01) in both Min and Landrace population. Further functional analysis revealed that E2F6 repressed the transcriptional efficiency of STAT3 in vitro, by binding the G allele of SNP1. The present study suggested that SNP1: g.-870 G>A was a piglet diarrhea-associated variant that directly affected binding with E2F6, leading to changes in STAT3 transcription which might partially contribute to piglet diarrhea susceptibility or resistance.

Testicular Transcriptome of Males and Pseudo-Males Provides Important New Insight into Sex Reversal of Rana dybowskii.

Rana dybowskii (R. dybowskii) is an ecological species found in China, Japan, Korea, and Russia. Like most amphibians, R. dybowskii lacks heterotypic sex chromosomes, limiting the in-depth study of sex determination and sex reversal mechanisms. Previous studies have shown that certain environmental factors can modify R. dybowskii genotypic females into phenotypic males, but the mechanism is still unknown. Considering the difficulties in identifying and collecting sex reversal gonads at different stages of differentiation under natural conditions, testes from sexually mature wild adult R. dybowskii were taken in this study, and the genotypic sex of individuals and sex reversal were identified by two male-linked genetic markers reported in our most recent findings. Transcriptome sequencing was performed on testicular tissue from males and pseudo-males, as well as female ovary tissue. The results show that the gene expression patterns of pseudo-males' testes were similar to those of the males but highly differed from females' ovaries. One hundred and seventeen differentially expressed genes between testes of pseudo-males and males were found, and the up-regulation of doublesex and mab-3 related transcription factor 1 (Dmrt1) in testes of pseudo-males may play a key role in R. dybowskii sex reversal.

Single nucleotide polymorphism-based analysis of the genetic structure of the Min pig conserved population.

OBJECTIVE: The study aims to uncover the genetic diversity and unique genetic structure of the Min pig conserved population, divide the nucleus conservation population, and construct the molecular pedigree. METHODS: We used KPS Porcine Breeding Chip v1 50K for SNP detection of 94 samples (31♂, 63♀) in the Min pig conserved population from Lanxi breeding Farm. RESULTS: The polymorphic marker ratio (PN), the observed heterozygosity (Ho), and the expected heterozygosity (He) were 0.663, 0.335, and 0.330, respectively. The pedigree-based inbreeding coefficients (FPED) was significantly different from those estimated from runs of homozygosity (FROH) and single nucleotide polymorphism (FSNP) based on genome. The Pearson correlation coefficient between FROH and FSNP was significant (p<0.05). The effective population content (Ne) showed a continuously decreasing trend. The rate of decline was the slowest from 200 to 50 generations ago (r = 0.95), then accelerated slightly from 50 to 5 generations ago (1.40

A 12-bp indel in the 3'UTR of porcine CISH gene associated with Landrace piglet diarrhea score.

Variations in Cytokine inducible SH2-containing protein (CISH) gene influence human susceptibility to common infectious diseases, but little is known about CISH in swine. The objectives of this study were to 1) determine porcine CISH (pCISH) mRNA expression level in different tissues of piglets, 2) predict putative functional genetic variations within pCISH, 3) investigate the association between a identified variation in the 3'UTR and piglets phenotype traits in Min (n = 226) and Landrace (n = 186) population, and explore the function of this variation. Results of quantitative PCR showed pCISH mRNA expressed in all the collected tissues with higher level in lung and ileum than colon (p < 0.05). In-silico analysis indicated none of the functional ns-SNPs existed in pCISH coding region. Results from the characterizing of 3'UTR presented a novel 12-bp insertion/deletion (indel) mutation. Statistical analysis demonstrated that this 12-bp indel associated with piglets diarrhea score in the Landrace population, and animals with AA genotype (12-bp insertion) presented lower diarrhea score when compared with BB (p < 0.05) or AB (p < 0.01) carriers. The in vitro study indicated that the luciferase activity of reconstruct plasmid psiCHECK-2-CISH-AA or psiCHECK-2-CISH-BB was significantly lower than the negative control (p < 0.05), and luciferase activity of psiCHECK-2-CISH-AA was higher than that of the psiCHECK-2-CISH-BB (p < 0.05). Although results herein suggested the 12-bp indel might affect Landrace piglet susceptibility to diarrhea, further association studies in more populations are needed before this preliminary finding could be used for pig breeding.

Characterization, mRNA expression profile, subcellular distribution and association analysis with piglet diarrhea of porcine matrix metallopeptidase 7 (pMMP7).

Matrix metalloproteinase 7 (MMP7) is involved in the degradation of extracellular matrix in disease processes and therefore plays an important role in host disease resistance/susceptibility. To better understanding the effects of porcine MMP7 (pMMP7) on piglets diarrhea trait, we characterized pMMP7 gene, identified genetic variations in pMMP7 and explored the relationship between pMMP7 polymorphisms and piglets diarrhea in Min pig and Landrace populations. The complete coding sequence of pMMP7 is 804 bp encoding a protein of 267 amino acids. Sequence alignment showed that the identity between pMMP7 and human MMP7 was approximately 80%. The expression of pMMP7 in the gut of healthy piglets were weak and the distribution of the pMMP7-EGFP fusion protein was observed mainly in the cytoplasm. After the identification of 21 genetic variations in 5' flanking region and exons, Hae III and Eco72 Ⅰ PCR-RFLP were established to genotype SNP rs327380117 and rs329429922, respectively. Statistical analysis indicated that Landrace piglets with a TT genotype at rs327380117 had a lower diarrhea score and day-14 wt than TC piglets (p < 0.05); the diarrhea score of AA Landrace animals with rs329429922 was lower than that of GG individuals (p < 0.05). The findings presented here contribute to the understanding of the biological function of pMMP7 and may provide new molecular markers for pig breeding.

Identification of mutations in porcine STAT5A that contributes to the transcription of CISH.

Identification of causative genes or genetic variants associated with phenotype traits benefits the genetic improvement of animals. CISH plays a role in immunity and growth, however, the upstream transcriptional factors of porcine CISH and the genetic variations in these factors remain unclear. In this study, we firstly identified the minimal core promoter of porcine CISH and confirmed the existence of STATx binding sites. Overexpression and RT-qPCR demonstrated STAT5A increased CISH transcriptional activity (P < 0.01) and mRNA expression (P < 0.01), while GATA1 inhibited CISH transcriptional activity (P < 0.01) and the following mRNA expression (P < 0.05 or P < 0.01). Then, the putative functional genetic variations of porcine STAT5A were screened and a PCR-SSCP was established for genotype g.508A>C and g.566C>T. Population genetic analysis showed the A allele frequency of g.508A>C and C allele frequency of g.566C>T was 0.61 and 0.94 in Min pigs, respectively, while these two alleles were fixed in the Landrace population. Statistical analysis showed that Min piglets with CC genotype at g.566C>T or Hap1: AC had higher 28-day body weight, 35-day body weight, and ADG than TC or Hap3: CT animals (P < 0.05, P < 0.05). Further luciferase activity assay demonstrated that the activity of g.508A>C in the C allele was lower than the A allele (P < 0.05). Collectively, the present study demonstrated that STAT5A positively regulated porcine CISH transcription, and SNP g.566C>T in the STAT5A was associated with the Min piglet growth trait.

KLF4, a Key Regulator of a Transitive Triplet, Acts on the TGF-ß Signaling Pathway and Contributes to High-Altitude Adaptation of Tibetan Pigs.

Tibetan pigs are native mammalian species on the Tibetan Plateau that have evolved distinct physiological traits that allow them to tolerate high-altitude hypoxic environments. However, the genetic mechanism underlying this adaptation remains elusive. Here, based on multitissue transcriptional data from high-altitude Tibetan pigs and low-altitude Rongchang pigs, we performed a weighted correlation network analysis (WGCNA) and identified key modules related to these tissues. Complex network analysis and bioinformatics analysis were integrated to identify key genes and three-node network motifs. We found that among the six tissues (muscle, liver, heart, spleen, kidneys, and lungs), lung tissue may be the key organs for Tibetan pigs to adapt to hypoxic environment. In the lung tissue of Tibetan pigs, we identified KLF4, BCL6B, EGR1, EPAS1, SMAD6, SMAD7, KDR, ATOH8, and CCN1 genes as potential regulators of hypoxia adaption. We found that KLF4 and EGR1 genes might simultaneously regulate the BCL6B gene, forming a KLF4-EGR1-BCL6B complex. This complex, dominated by KLF4, may enhance the hypoxia tolerance of Tibetan pigs by mediating the TGF-ß signaling pathway. The complex may also affect the PI3K-Akt signaling pathway, which plays an important role in angiogenesis caused by hypoxia. Therefore, we postulate that the KLF4-EGR1-BCL6B complex may be beneficial for Tibetan pigs to survive better in the hypoxia environments. Although further molecular experiments and independent large-scale studies are needed to verify our findings, these findings may provide new details of the regulatory architecture of hypoxia-adaptive genes and are valuable for understanding the genetic mechanism of hypoxic adaptation in mammals.

Expression pattern and association analysis of porcine matrix metallopeptidase 9 (MMP9) with diarrhea and performance traits in piglets.

Matrix metalloproteinase 9 (MMP9) plays critical roles in multiple biological processes, such as reproduction, cell proliferation and differentiation, and host defenses. The aim of this study was to evaluate whether MMP9 is a candidate gene for resistance to diarrhea in piglets. In this study, quantitative real-time PCR was used to analyze the expression of MMP9 mRNA in different tissues of specific pathogen-free piglets. MMP9 was expressed in all the tissues (heart, liver, spleen, lung, kidney, stomach, duodenum, jejunum, ileum, and colon) analyzed. An association analysis between MMP9 polymorphisms and piglet diarrhea score and performance traits were performed in Min (Chinese indigenous breed) and Landrace populations. In the statistical analysis, at the g.48178429 G>A locus, AA piglets had a lower diarrhea score than that of GA in the Min population (P < .05), whereas GG had higher day-35 body weight and average daily gain (ADG) than AA in the Landrace breed (P < .05). At the rs336583561 locus, Min piglets with the GG genotype have a lower diarrhea score than AG piglets (P < .05). At g.48184777C>T, CC animals have higher body weight than TC Landrace piglets (P < .05 or P < .01). A 5' flanking deletion assay indicated that g.48178429 G>A was not located in the MMP9 promoter region. Our results suggest that the A allele at the g.48178429 G>A locus and the G allele at rs336583561 are resistance alleles in Min pigs. Before these markers are used in pig breeding programs, more studies in larger populations are needed.

Identification of porcine CTLA4 gene polymorphism and their association with piglet diarrhea and performance traits.

The objective of this study was to evaluate the association between the cytotoxic T-lymphocyte-associated antigen 4 (CTLA4) gene and piglet diarrhea. In this study, the mRNA expression of the CTLA4 gene increased significantly in IPEC-J2 cells after Escherichia coli K88 infection. Single nucleotide polymorphisms (SNPs) located in the 5' flanking region (SNPs g.107281989C>T) and 3'-untranslated region (3'-UTR; SNPs g.107288753C>A) were identified, and they were in linkage disequilibrium in both Min pigs and the Landrace population. Association analysis showed that Landrace piglets with a TT or AA genotype had a lower diarrhea index, and AA animals had higher average daily gain when compared to CC pigs, respectively (p < 0.05). However, the relationship between SNPs and diarrhea and performance traits in the Min population was not significant. Haplotype analysis indicated that the TC haplotype had the lowest diarrhea index. The 5' flanking deletion assay suggested that SNP g.107281989C>T was a molecular marker instead of the functional marker. This research demonstrated that genetic variances in the CTLA4 gene had significant effects on Landrace piglet diarrhea resistance.

Distinct Patterns of PPARγ Promoter Usage, Lipid Degradation Activity, and Gene Expression in Subcutaneous Adipose Tissue of Lean and Obese Swine.

Subcutaneous adipose tissue is a loose connective tissue specializing in the regulation of energy storage and metabolization. In domesticated pigs (Sus scrofa), the temporal development of subcutaneous adipose tissue is critical for meat production. However, the regulation of adipose tissue development remains unclear. Here, the subcutaneous adipose tissue development was characterized and compared in lean (Danish-Landrace) and obese (Min) pigs at juvenile and the juvenile-to-adult growth stages. Using RNA sequencing, we profiled the transcriptome of subcutaneous adipose tissue isolated from 4- and 16-week-old pigs and identified 24,718 expressed transcription units. Of them, 6327 genes were differentially expressed between the breeds and/or developmental stages. Compared with obese pigs, upregulated genes in lean pigs showed significant function and pathway enrichment in fatty acid degradation and mitochondrial functions. Further analysis uncovered the distinct usage preferences of the three alternative peroxisome proliferator-activated receptor γ (PPARγ) promoters associated with the development of subcutaneous adipose tissue in both breeds. Transcriptome analysis of subcutaneous adipose tissue in lean and obese pigs suggested that marker-assisted selection of fatty acid degradation and PPARγ signaling pathways could be important directions for future pork quality improvement and modern breeding.

Characterization of porcine cytokine inducible SH2-containing protein gene and its association with piglet diarrhea traits.

OBJECTIVE: The cytokine inducible SH2-containing protein (CISH), which might play a role in porcine intestine immune responses, was one of the promising candidate genes for piglet anti-disease traits. An experiment was conducted to characterize the porcine CISH (pCISH) gene and to evaluate its genetic effects on pig anti-disease breeding. METHODS: Both reverse transcription polymerase chain reaction (RT-PCR) and PCR were performed to obtain the sequence of pCISH gene. A pEGFP-C1-CISH vector was constructed and transfected into PK-15 cells to analysis the distribution of pCISH. The sequences of individuals were compared with each other to find the polymorphisms in pCISH gene. The association analysis was performed in Min pigs and Landrace pigs to evaluate the genetic effects on piglet diarrhea traits. RESULTS: In the present research, the coding sequence and genomic sequence of pCISH gene was obtained. Porcine CISH was mainly localized in cytoplasm. TaqI and HaeIII PCR restriction fragment length polymorphism (RFLP) assays were established to detect single nucleotide polymorphisms (SNPs); A-1575G in promoter region and A2497C in Intron1, respectively. Association studies indicated that SNP A-1575G was significantly associated with diarrhea index of Min piglets (p<0.05) and SNP A2497C was significantly associated with the diarrhea trait of both Min pig and Landrace piglets (p<0.05). CONCLUSION: This study suggested that the pCISH gene might be a novel candidate gene for pig anti-disease traits, and further studies are needed to confirm the results of this preliminary research.

Characterization and association analysis with litter size traits of porcine matrix metalloproteinase-9 gene (pMMP-9).

The mammalian matrix metalloproteinase-9 (MMP-9), which might play a role in ovulation, uterus remodeling, embryo development, and implantation in mammals, is one of the potential functional candidate genes for porcine reproductive traits. In this study, the entire genomic sequence of porcine MMP-9 (pMMP-9) gene was established; it contains 13 exons and 12 introns. Real-time PCR analysis revealed that pMMP-9 is highly expressed in the Minzhu uterus before puberty and decreases significantly after sexual maturity (p < 0.05). Two single-nucleotide polymorphisms (A3011G and T5079C) that can be detected by PCR restriction fragment length polymorphism (PCR-RFLP) were discovered and tested for statistical associations with litter size traits in a crossbred population (Line DIV) derived from Landrace, Large White, Chinese Tongcheng and/or Chinese Meishan pigs. For A3011G, the GG genotype was associated with a significantly higher (p < 0.05) number of live births than those recorded for AA sows and the additive effect was significant (p < 0.05). The T5079C marker is not associated with litter size in this population. Further studies are needed to confirm the results of this study.

[Screening and identification of differentially expressed genes in Beijing fatty and broiler breast muscles].

mRNA differential display reverse-transcripton PCR(DDRT-PCR) was applied to identify differentially expressed genes in Arbor Acres broiler(AA) and Beijing fatty chicken breast muscles in order to find the mechanism which induces the differential gene expression at the molecular level. A total of 7 ESTs were found using reverse Northern dot blot, and all of them were compared with the nucleotide sequences in GenBank database using BLAST. S1 was highly similar to HMGN3; S3 was highly similar to ChEST294a8 with unknown functions; S4 and S5 were highly similar to PGM; S6 and S2 had highly similar nucleotide sequences with unknown functions in nucleotide databases; S7 had no significant similarity with existing genes or ESTs and was regarded as a new EST. The new EST was submitted to GenBank(Accession number: EU594549). This lays a foundation for further study on the mechanism of differential gene expression in Beijing fatty and AA breast muscles.