The prevalence and influencing factors of frailty in patients with chronic kidney disease: a systematic review and meta-analysis.

BACKGROUND: To investigate the prevalence and influencing factors of frailty and pre-frailty in chronic kidney disease (CKD) patients and thereby provide a scientific basis for effective avoidance of frailty in patients with CKD. METHODS: PubMed, EMBASE, Web of Science, EBSCO, Cochrane Library, CNKI, VIP, CBMdisc, and Wanfang databases were searched for relevant studies published till December 31, 2021. The summary results were described as odds ratios (ORs) or standardized mean differences (SMDs) with 95% confidence intervals (CIs). A meta-analysis was performed using StataSE12.0. RESULTS: Fifteen published studies, which enrolled a total of 3294 CKD patients, met the inclusion criteria. The combined prevalence of frailty in CKD patients was 38.1% (95% CI 29.7-46.5%) and pre-frailty was 37.9% (95% CI 32.7-43.1%). The main factors influencing frailty in CKD patients were age (SMD 0.524, 95% CI 0.326-0.723), diastolic blood pressure (SMD - 0.294, 95% CI - 0.518 to - 0.071), body mass index (BMI) (SMD - 0.267, 95% CI - 0.471 to - 0.064), grip strength (SMD - 0.929, 95% CI - 1.233 to - 0.626), hemoglobin level (SMD - 0.346, 95% CI - 0.448 to - 0.243), serum albumin level (SMD - 0.533, 95% CI - 0.655 to - 0.411), Charlson Comorbidity Index (SMD 0.421, 95% CI 0.150-0.692), multiple medications (SMD 0.625, 95% CI 0.354-0.895), Mini-Mental State Examination (MMSE) score (SMD - 0.563, 95% CI - 0.846 to - 0.280), and female (OR 2.391, 95% CI 1.236-4.627). CONCLUSION: Frailty is common in CKD patients. The prevalence of frailty among CKD patients was related to age, diastolic blood pressure, BMI, grip strength, hemoglobin and serum albumin levels, Charlson Comorbidity Index, multiple medications, MMSE score, and female.

Selection of suitable reference genes for qRT-PCR analysis of Begonia semperflorens under stress conditions.

Begonia semperflorens (B. semperflorens), belonging to the family Begoniaceae, has now been widely cultivated worldwide and is famous for its ornamental plants with colourful flowers and distinctive leaves. The selection of appropriate internal reference genes is very important to accurately determine target gene expression via quantitative real-time PCR. However, internal reference gene selection has never been conducted in B. semperflorens. In this study, seven candidate reference genes of B. semperflorens, including 18S ribosomal RNA (Bs18S), pentatricopeptide repeat-containing protein (BsPPR), actin-related protein 5 isoform X2 (BsACT), DNAJ homologue subfamily C member 17 (BsDNAJ), glyceraldehyde-3-phosphate dehydrogenase (BsGAPDH), NAD-dependent malic enzyme 59 kDa isoform, mitochondria (BsNAD-ME), and peptidyl-prolyl cis-trans isomerase CYP26-2, chloroplast (BsCYP), which were obtained from our previous studies, were selected. The stabilities of these genes under stress conditions were analysed using geNorm and NormFinder. Validation of target gene expressions, including phenylalanine ammonia-lyase (BsPAL) and respiratory burst oxidase homologue D (BsRBOHD) under biotic and abiotic conditions, phenylalanine ammonia-lyase (BsPAL), anthocyanidin synthase (BsANS), chalcone synthase (BsCHS), and flavanone-3-hydroxylase (BsF3H) under low temperature, using these seven internal reference genes for normalisation further confirmed the stabilities of the selected genes and indicated the need for reference gene selection for normalising gene expressions in B. semperflorens. Of the seven candidate reference genes, the combination of BsACT, BsDNAJ, and BsNAD-ME was the ideal reference gene set for normalising gene expression in samples under biotic conditions. BsCYP combined with BsACT or BsGAPDH was the best reference gene pair under abiotic conditions. BsACT and BsPPR could be combined to normalise gene expression under low temperature. Our results will benefit future studies on gene expression in plants of Begoniaceae.

Population Genetic Analysis of Phytophthora parasitica From Tobacco in Chongqing, Southwestern China.

Tobacco black shank, caused by Phytophthora parasitica, is one of the most notorious tobacco diseases and causes huge economic losses worldwide. Understanding the genetic variation of P. parasitica populations is essential to the development of disease control measures. In this research, 210 simple sequence repeat (SSR) markers for P. parasitica were identified, 10 of which were polymorphic among nine reference strains. We further performed population genetic analysis of 245 P. parasitica isolates randomly collected from tobacco fields in Chongqing for mating type, molecular variation at 14 SSR loci (four of which were identified previously), and sensitivity to the fungicide metalaxyl. The results showed that the A2 mating type was dominant and no A1 mating type isolate was discovered. SSR genotyping distinguished 245 P. parasitica isolates into 46 genotypes, four of which were dominant in the population. Low genotypic diversity and excess heterozygosity were common in nearly all of the populations from Chongqing. Population analysis showed that no differentiation existed among different populations. All isolates tested were highly sensitive to metalaxyl. Taken together, our results showed that the P. parasitica populations from tobacco fields in Chongqing belonged to a clonal lineage and were highly sensitive to metalaxyl.

An RXLR effector secreted by Phytophthora parasitica is a virulence factor and triggers cell death in various plants.

RXLR effectors encoded by Phytophthora species play a central role in pathogen-plant interactions. An understanding of the biological functions of RXLR effectors is conducive to the illumination of the pathogenic mechanisms and the development of disease control strategies. However, the virulence function of Phytophthora parasitica RXLR effectors is poorly understood. Here, we describe the identification of a P. parasitica RXLR effector gene, PPTG00121 (PpE4), which is highly transcribed during the early stages of infection. Live cell imaging of P. parasitica transformants expressing a full-length PpE4 (E4FL)-mCherry protein indicated that PpE4 is secreted and accumulates around haustoria during plant infection. Silencing of PpE4 in P. parasitica resulted in significantly reduced virulence on Nicotiana benthamiana. Transient expression of PpE4 in N. benthamiana in turn restored the pathogenicity of the PpE4-silenced lines. Furthermore, the expression of PpE4 in both N. benthamiana and Arabidopsis thaliana consistently enhanced plant susceptibility to P. parasitica. These results indicate that PpE4 contributes to pathogen infection. Finally, heterologous expression experiments showed that PpE4 triggers non-specific cell death in a variety of plants, including tobacco, tomato, potato and A. thaliana. Virus-induced gene silencing assays revealed that PpE4-induced cell death is dependent on HSP90, NPK and SGT1, suggesting that PpE4 is recognized by the plant immune system. In conclusion, PpE4 is an important virulence RXLR effector of P. parasitica and recognized by a wide range of host plants.