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Skeletal stem cells (SSC) have gained attentions as candidates for the treatment of osteoarthritis due to their osteochondrogenic capacity. However, the immunomodulatory properties of SSC, especially under delivery operations, have been largely ignored. In the study, we found that Pdpn+ and Grem1+ SSC subpopulations owned immunoregulatory potential, and the single-cell RNA sequencing (scRNA-seq) data suggested that the mechanical activation of microgel carriers on SSC induced the generation of Pdpn+Grem1+Ptgs2+ SSC subpopulation, which was potent at suppressing macrophage inflammation. The microgel carriers promoted the YAP nuclear translocation, and the activated YAP protein was necessary for the increased expression of Ptgs2 and PGE2 in microgels-delivered SSC, which further suppressed the expression of TNF-ɑ, IL-1β and promoted the expression of IL-10 in macrophages. SSC delivered with microgels yielded better preventive effects on articular lesions and macrophage activation in osteoarthritic rats than SSC without microgels. Chemically blocking the YAP and Ptgs2 in microgels-delivered SSC partially abolished the enhanced protection on articular tissues and suppression on osteoarthritic macrophages. Moreover, microgel carriers significantly prolonged SSC retention time in vivo without increasing SSC implanting into osteoarthritic joints. Together, our study demonstrated that microgel carriers enhanced SSC reprogramming towards immunomodulatory phenotype to regulate macrophage phenotype transformation for effectively osteoarthritic therapy by promoting YAP protein translocation into nucleus. The study not only complement and perfect the immunological mechanisms of SSC-based therapy at the single-cell level, but also provide new insight for microgel carriers in stem cell-based therapy.

Background: To assess the alterations in gingival thickness and the occurrence gingival recession subsequent to orthodontic-orthognathic treatment of mandibular incisors in skeletal Class III and identify risk factors associated with gingival recession. Methods: In this retrospective cohort study, we enrolled 33 patients exhibiting skeletal Class III malocclusion, totaling 131 mandibular incisors, who were undergoing orthodontic- orthognathic treatment that did not involve extraction of mandibular teeth. The subjects were categorized into surgery group (S; n = 17; ANB = −5.55 ± 3.26; IOFTN = 4.60 ± 0.51, scores ranging: 4.3–5.3) and non-surgery group (NS; n = 16; ANB = −3.00 ± 4.08; IOFTN = 4.63 ± 0.50, scores ranging: 4.3–5.4), based on if they had history of Periodontally Accelerated Osteogenic Orthodontics surgery (S) or not (NS). Patients in S group received orthognathic surgery about 1–1.5 years after Periodontally Accelerated Osteogenic Orthodontics surgery. Alterations in gingival thickness, gingival recession, and keratinized gingival width were compared before and after orthodontic-orthognathic treatment. Logistic regression analysis was used to construct a gingival recession prediction model and draw nomograms. Results: After orthodontic-orthognathic treatment, the gingival thickness and keratinized gingival width in NS group decreased by 0.15 ± 0.21 mm and 0.74 ± 0.91 mm, whereas those in the S group increased by 0.32 ± 0.28 mm and 2.09 ± 1.51 mm (P

Abstract Background Though articular cartilage stem cell (ACSC)-based therapies have been demonstrated to be a promising option in the treatment of diseased joints, the wide variety of cell isolation, the unknown therapeutic targets, and the incomplete understanding of the interactions of ACSCs with diseased microenvironments have limited the applications of ACSCs. Methods In this study, the human ACSCs have been isolated from osteoarthritic articular cartilage by advantage of selection of anatomical location, the migratory property of the cells, and the combination of traumatic injury, mechanical stimuli and enzymatic digestion. The protective effects of ACSC infusion into osteoarthritis (OA) rat knees on osteochondral tissues were evaluated using micro-CT and pathological analyses. Moreover, the regulation of ACSCs on osteoarthritic osteoclasts and the underlying mechanisms in vivo and in vitro were explored by RNA-sequencing, pathological analyses and functional gain and loss experiments. The one-way ANOVA was used in multiple group data analysis. Results The ACSCs showed typical stem cell-like characteristics including colony formation and committed osteo-chondrogenic capacity. In addition, intra-articular injection into knee joints yielded significant improvement on the abnormal subchondral bone remodeling of osteoarthritic rats. Bioinformatic and functional analysis showed that ACSCs suppressed osteoarthritic osteoclasts formation, and inflammatory joint microenvironment augmented the inhibitory effects. Further explorations demonstrated that ACSC-derived tumor necrosis factor alpha-induced protein 3 (TNFAIP3) remarkably contributed to the inhibition on osteoarhtritic osteoclasts and the improvement of abnormal subchondral bone remodeling. Conclusion In summary, we have reported an easy and reproducible human ACSC isolation strategy and revealed their effects on subchondral bone remodeling in OA rats by releasing TNFAIP3 and suppressing osteoclasts in a diseased microenvironment responsive manner. Graphical abstract

Background/purpose: Alveolar bone fenestration and dehiscence is common in untreated patients and potentially harmful. This study was to evaluate the effect of augmented corticotomy (AC) on the prevention and treatment of alveolar bone defects in skeletal class III high-angle patients during presurgical orthodontic treatment (POT). Materials and methods: Fifty patients with skeletal Class III high-angle malocclusion were enrolled, of whom 25 patients (G1) underwent traditional POT and 25 patients (G2) received AC during POT. The alveolar bone fenestration and dehiscence around the upper and lower anterior teeth were measured by CBCT. The incidence and transition of fenestration and dehiscence in the two groups were compared by the chisquare and Mann‒Whitney rank-sum tests. Results: Before treatment (T0), the incidence of fenestration and dehiscence around the anterior teeth of all patients was 39.24% and 24.10%, respectively. After POT (T1), the incidence of fenestration in G1 and G2 was 49.83% and 25.86%, respectively, and the incidence of dehiscence in G1 and G2 was 58.08% and 32.07%, respectively. For teeth without fenestration and dehiscence at T0, more anterior teeth in G1 exhibited fenestration and dehiscence at T1 than in G2. For teeth with fenestration and dehiscence at T0, most transitions in G1 were maintained or worsened, but “cure” cases were observed in G2. After POT, the cure rates of fenestration and dehiscence in G2 were 80.95% and 91.07%, respectively. Conclusion: During the POT of skeletal Class III high-angle patients, augmented corticotomy can significantly treat and prevent alveolar bone fenestration and dehiscence around anterior teeth.

Abstract Background Repairing radiation-induced bone injuries remains a significant challenge in the clinic, and few effective medicines are currently available. Psoralen is a principal bioactive component of Cullen corylifolium (L.) Medik and has been reported to have antitumor, anti-inflammatory, and pro-osteogenesis activities. However, less information is available regarding the role of psoralen in the treatment of radiation-induced bone injury. In this study, we explored the modulatory effects of psoralen on skeletal stem cells and their protective effects on radiation-induced bone injuries. Methods The protective effects of psoralen on radiation-induced osteoporosis and irradiated bone defects were evaluated by microCT and pathological analysis. In addition, the cell proliferation, osteogenesis, and self-renewal of SSCs were explored. Further, the underlying mechanisms of the protective of psoralen were investigated by using RNA sequencing and functional gain and loss experiments in vitro and in vivo. Statistical significance was analyzed using Student's t test. The one-way ANOVA was used in multiple group data analysis. Results Here, we demonstrated that psoralen, a natural herbal extract, mitigated radiation-induced bone injury (irradiation-induced osteoporosis and irradiated bone defects) in mice partially by rescuing the stemness of irradiated skeletal stem cells. Mechanistically, psoralen restored the stemness of skeletal stem cells by alleviating the radiation-induced suppression of AKT/GSK-3β and elevating NRF2 expression in skeletal stem cells. Furthermore, the expression of KEAP1 in skeletal stem cells did not significantly change in the presence of psoralen. Moreover, blockade of NRF2 in vivo partially abolished the promising effects of psoralen in a murine model of irradiation-induced osteoporosis and irradiated bone regeneration. Conclusions In summary, our findings identified psoralen as a potential medicine to mitigate bone radiation injury. In addition, skeletal stem cells and AKT-GSK-3β and NRF2 may thus represent therapeutic targets for treating radiation-induced bone injury. Graphical Abstract

Plants have evolved sophisticated systems to cope with the environmental stresses, with the heat shock factor (HSF) family proteins composing an integral part of the transcriptional regulation system. Understanding the evolutionary history and functional diversity of HSFs will facilitate improving tolerance of crops to adverse environmental conditions. In this study, genome-wide analysis of Secale cereale identified 31 HSF genes. The total number of HSF genes in S. cereale is larger than that in barley and the three subgenomes of wheat, suggesting it is a valuable resource for mining functional HSFs. Chromosome analysis revealed an uneven distribution of HSF genes among the 7 S. cereale chromosomes, with no HSF gene was detected on chromosome 4. Further interspecies synteny analysis revealed that chromosome reorganization during species-speciation may lead to the escape of HSF genes from the S. cereale chromosome 4. Phylogenetic analysis revealed that S. cereale experienced more HSF gene duplications than barley and the three wheat subgenomes. Expression analysis demonstrated that S. cereale HSF genes showed diverse expression patterns across plant developmental stages and upon drought and freezing treatment, suggesting functional diversity of the gene family. Notably, we detected distinct expression patterns for a recently duplicated HSF gene pair, indicating functional divergence may have occurred between the two genes. The study presents the genome organization, evolutionary features and expression patterns of the S. cereale HSF genes. These results provide new insights into the evolution of HSF genes in Triticeae and may serve as a resource for Triticeae molecular breeding.

Background: Hepatic inflow occlusion proceeded to reduce blood loss during hepatectomy induces ischemia-reperfusion (IR) injury in the remnant liver. Dexmedetomidine, a selective α2-adrenoceptor agonist used as an anesthetic adjuvant, has been shown to attenuate IR injury in preclinical and clinical studies. However, a meta-analysis is needed to systematically evaluate the protective effect of perioperative dexmedetomidine use on IR injury induced by hepatectomy.Methods: A prospectively registered meta-analysis following Cochrane and PRISMA guidelines concerning perioperative dexmedetomidine use on IR injury after hepatectomy was performed via searching Cochrane Library, PubMed, EMBASE, ClinicalTrials.gov, Web of Science, CNKI, WanFang, and Sinomed for eligible randomized controlled trials up to 2021.3.31. The main outcome is postoperative liver function. Risk of bias was assessed by the Cochrane Risk of Bias tool. Review Manager 5.3 and Stata12.0 were applied to perform data analyses.Results: Eight RCTs enrolling 468 participants were included. Compared with 0.9% sodium chloride, dexmedetomidine decreased serum concentration of ALT (WMD = −66.54, 95% CI: −92.10–−40.98), AST (WMD= −82.96, 95% CI: −106.74–−59.17), TBIL (WMD = −4.51, 95% CI: −7.32–−1.71), MDA (WMD = −3.09, 95% CI: −5.17–−1.01), TNF-α (WMD = −36.54, 95% CI: −61.33–−11.95) and IL-6 (WMD = −165.05, 95% CI: −225.76–−104.34), increased SOD activity (WMD = 24.70, 95% CI: 18.09–31.30) within postoperative one day. There was no significant difference in intraoperative or postoperative recovery parameters between groups.Conclusions: Perioperative administration of dexmedetomidine can exert a protective effect on liver IR injury after hepatectomy. Additional studies are needed to further evaluate postoperative recovery outcomes of dexmedetomidine with different dosing regimens.

AIM: To study whether specific anesthetic drugs or tear layer evaporation was primarily responsible for the acute cataract and what the change of lens structure is in anesthetized mice. METHODS: Five groups were set up in the experiment: Group A (topicamide and phenylephrine mixed eye drop+ chloral hydrate), Group B (tropicamide and phenylephrine mixed eye drop+sevoflurane), Group C (tropicamide and phenylephrine mixed eye drop), Group D (topicamide and phenylephrine mixed eye drop+chloral hydrate, carbomer eye drop in the right eyes), and Group E (tropicamide and phenylephrine mixed eye drop+sevoflurane, carbomer eye drop in the right eyes). A simple classification system was used to assess the severity of lens opacity. And a numerical value from 0 to 3 to each grade was assigned for the cataract index calculation and data analysis. The gross appearance and time course of development of lens opacity were assessed. Hematoxylin and eosin staining was used to observe the lens structure changes in the reversible cataract. RESULTS: Tropicamide did not induce lens opacification in mice. Lens opacity caused by inhaled sevoflurane was similar to injected cholral hydrate. Both inhaled-anesthetic-induced lens opacity and injected-anesthetic-induced lens opacity could be prevented by carbomer eye drop. In the severe opacity lens, a wide range of lens fiber cell structure had disordered. The fiber cells became uneven thickness. CONCLUSION: The acute reversible lens opacity can unilaterally develop or be induced by a local cause. The structure of lens fiber cells changed in the lens opacity which may influence the permanent connection of the lens fiber cells. This study was not only of practical significance to help maintain lens transparency for eye research, but also of the deeper consideration about the reversible lens opacification phenomenon.

Percutaneous coronary intervention (PCI) is the most widely used therapy for treating ischemic heart disease. However, intimal hyperplasia and restenosis usually occur within months after angioplasty. Modern pharmacological researchers have proven that osthole, the major active coumarin of Cnidium monnieri (L.) Cusson, exerts potent antiproliferative effects in lung cancer cells, the human laryngeal cancer cell line RK33 and TE671 medulloblastoma cells, and its mechanism of action is related to cell cycle arrest. The goal of the present study was to observe the effect of osthole on vascular smooth muscle cell (VSMC) proliferation using platelet-derived growth factor-BB (PDGF-BB)-stimulated VSMCs isolated from rats and vascular balloon injury as models to further elucidate the molecular mechanisms underlying this activity. We detected the relative number of VSMCs by the MTT assay and EdU staining and examined cell cycle progression by flow cytometry. To more deeply probe the mechanisms, the protein expression levels of PCNA, the cyclin D1/CDK4 complex and the cyclin E1/CDK2 complex in balloon-treated rat carotid arteries and the mRNA and protein expression levels of the cyclin D1/CDK4 and cyclin E1/CDK2 complexes in VSMCs were detected by real-time RT-PCR and western blotting. The data showed that osthole significantly inhibited the proliferation of VSMCs induced by PDGF-BB. Furthermore, osthole caused apparent VSMC cycle arrest early in G0/G1 phase and decreased the expression of cyclin D1/CDK4 and cyclin E1/CDK2. Our results demonstrate that osthole can significantly inhibit PDGF-BB-induced VSMC proliferation and that its regulatory effects on cell cycle progression and proliferation may be related to the downregulation of cyclin D1/CDK4 and cyclin E1/CDK2 expression as well as the prevention of cell cycle progression from G0/G1 phase to S phase. The abovementioned mechanism may be responsible for the alleviation of neointimal hyperplasia in balloon-induced arterial wall injury by osthole.

Abstract Background Asthma is a common complex chronic, inflammatory polygenic disease with heterogeneous manifestations, affecting individuals of all age groups and posing an immense burden on healthcare resources. A number of studies have identified the association between a disintegrin and metalloprotease 33 (ADAM33) polymorphisms and asthma risk, however, the results still remain inconclusive. The objective of the present study was to identify the effect of ADAM33 variants in asthma susceptibility. Methods Eligible case-control studies published between January 2000 and June 2018 was searched and retrieved from online electronic databases. The odds ratio (OR) with its 95% confidence interval (CI) was employed to calculate the effect. Results A total of 63 case-control studies were finally screened out, including 13,280 asthma patients and 13,340 controls. Eleven SNPs of ADAM33 gene were identified. Our results detected a significant association between ADAM33 T2, Q1, F + 1 and AA genotype of T + 1 polymorphisms and asthma risk in total population. Subgroup analysis by ethnicities showed that the alleles and genotypes of T2, Q1 and F + 1 polymorphisms were associated with asthma susceptibility among Asian populations, while V4 polymorphism was associated with asthma among Caucasian populations. Subgroup analysis by ages showed that T2, F + 1 and ST + 4 polymorphisms were associated with childhood asthma, while Q1 and V4 polymorphisms were associated with asthma risk in adults. Subgroup analysis by asthma severity showed that only the G allele of ADAM33 T1 polymorphism was associated with the severity of asthma when compared with the controls. In addition, T2, Q1 and F + 1 polymorphisms of ADAM33 were significantly associated with increased the asthma risk in Chinese asthma patients. Conclusions Our results found that T2, Q1 and F + 1 polymorphisms of ADAM33 gene might contribute to asthma risk. Future well-designed case-control studies with large population and more ethnicities are still needed to estimate the association.

Nucleotide-binding leucine-rich repeat (NLR) genes play a key role in plant immune responses and have co-evolved with pathogens since the origin of green plants. Comparative genomic studies on the evolution of NLR genes have been carried out in several angiosperm lineages. However, most of these lineages come from the dicot clade. In this study, comparative analysis was performed on NLR genes from five Arecaceae species to trace the dynamic evolutionary pattern of the gene family during species speciation in this monocot lineage. The results showed that NLR genes from the genomes of Elaeis guineensis (262), Phoenix dactylifera (85), Daemonorops jenkinsiana (536), Cocos nucifera (135) and Calamus simplicifolius (399) are highly variable. Frequent domain loss and alien domain integration have occurred to shape the NLR protein structures. Phylogenetic analysis revealed that NLR genes from the five genomes were derived from dozens of ancestral genes. D. jenkinsiana and E. guineensis genomes have experienced “consistent expansion” of the ancestral NLR lineages, whereas a pattern of “first expansion and then contraction” of NLR genes was observed for P. dactylifera, C. nucifera and C. simplicifolius. The results suggest that rapid and dynamic gene content and structure variation have shaped the NLR profiles of Arecaceae species.

Suaeda salsa, an annual succulent halophytic herb, is one of the major halophyte widely distributed in both saline inland and the intertidal zone. In this study, we report the complete chloroplast genome (plastome) of S. salsa. The plastome was 151,642 bp in length and comprises a large single-copy region (83,502 bp), a small single-copy region (17,780 bp), and a pair of inverted repeats (25,180 bp). It encodes 113 unique genes, including 79 protein-coding genes (PCGs), 30 tRNAs, and four rRNAs. The overall GC content of this plastome was 36.4%. Phylogenomic analysis based on 20 plastomes revealed that S. salsa was closely related to S. malacosperma.

The complete chloroplast genome (plastome) of Chenopodium glaucum, an annual halophytic herb, was determined. The plastome was 152,191 bp in size, containing a large single-copy region (83,675 bp), a small single-copy region (18,130 bp), and two inverted repeats regions (25,193 bp). The overall GC content of this plastome was 37.2%. In total, 113 unique genes were annotated including 79 protein-coding genes (PCGs), 30 tRNAs and 4 rRNAs. Phylogenomic analysis showed that C. glaucum was sister to C. album.

OBJECTIVE:To evaluate the comparative efficacy and safety of saxagliptin for type 2 diabetes (T2D). METHODS:A systematic search of PubMed, Embase, the Cochrane Library, Web of Science, ClinicalTrials.gov and two Chinese databases for randomized controlled trials (RCTs) comparing saxagliptin with placebo or active comparators was performed up to July 2017. A complementary search was done to cover literature until March 2018. For continuous data, estimates were pooled using inverse variance methodology to calculate weighted mean differences (WMDs). Dichotomous data were presented as Mantel-Haenzel risk ratios (RRs). RESULTS:Thirty-nine references of 30 RCTs involving 29,938 patients were analyzed. Compared with placebo, saxagliptin significantly reduced glycated hemoglobin (HbA1c, WMD -0.52%, 95% CI -0.60 to -0.44) and fasting plasma glucose (WMD -13.78 mg/dL, 95% CI -15.31 to -12.25), and increased the proportion of patients achieving HbA1c

Axon guidance molecule Slit is critical for the axon repulsion in neural tissues, which is evolutionarily conserved from planarians to humans. However, the function of Slit in the silkworm Bombyx mori was unknown. Here we showed that the structure of Bombyx mori Slit (BmSlit) was different from that in most other species in its C-terminal sequence. BmSlit was localized in the midline glial cell, the neuropil, the tendon cell, the muscle and the silk gland and colocalized with BmRobo1 in the neuropil, the muscle and the silk gland. Knock-down of Bmslit by RNA interference (RNAi) resulted in abnormal development of axons and muscles. Our results suggest that BmSlit has a repulsive role in axon guidance and muscle migration. Moreover, the localization of BmSlit in the silk gland argues for its important function in the development of the silk gland.

Coevolution is important for the maintenance of the interaction between a ligand and its receptor during evolution. The interaction between axon guidance molecule Slit and its receptor Robo is critical for the axon repulsion in neural tissues, which is evolutionarily conserved from planarians to humans. However, the mechanism of coevolution between Slit and Robo remains unclear. In this study, we found that coordinated amino acid changes took place at interacting sites of Slit and Robo by comparing the amino acids at these sites among different organisms. In addition, the high level correlation between evolutionary rate of Slit and Robo was identified in vertebrates. Furthermore, the sites under positive selection of slit and robo were detected in the same lineage such as mosquito and teleost. Overall, our results provide evidence for the coevolution between Slit and Robo.

Dysfunctional gene expression in nociceptive pathways plays a critical role in the development and maintenance of neuropathic pain. Super enhancers (SEs), composed of a large cluster of transcriptional enhancers, are emerging as new players in the regulation of gene expression. However, whether SEs participate in nociceptive responses remains unknown. Here, we report a spinal-specific SE (SS-SE) that regulates chronic constriction injury (CCI)-induced neuropathic pain by driving Ntmt1 and Prrx2 transcription in dorsal horn neurons. Peripheral nerve injury significantly enhanced the activity of SS-SE and increased the expression of NTMT1 and PRRX2 in the dorsal horn of male mice in a bromodomain-containing protein 4 (BRD4)-dependent manner. Both intrathecal administration of a pharmacological BRD4 inhibitor JQ1 and CRISPR-Cas9-mediated SE deletion abolished the increased NTMT1 and PRRX2 in CCI mice and attenuated their nociceptive hypersensitivities. Furthermore, knocking down Ntmt1 or Prrx2 with siRNA suppressed the injury-induced elevation of phosphorylated extracellular-signal-regulated kinase (p-ERK) and glial fibrillary acidic protein (GFAP) expression in the dorsal horn and alleviated neuropathic pain behaviors. Mimicking the increase in spinal Ntmt1 or Prrx2 in naive mice increased p-ERK and GFAP expression and led to the genesis of neuropathic pain-like behavior. These results redefine our understanding of the regulation of pain-related genes and demonstrate that BRD4-driven increases in SS-SE activity is responsible for the genesis of neuropathic pain through the governance of NTMT1 and PRRX2 expression in dorsal horn neurons. Our findings highlight the therapeutic potential of BRD4 inhibitors for the treatment of neuropathic pain. [ABSTRACT FROM AUTHOR]

Taraxasterol is one of the bioactive ingredients from traditional Chinese herb Taraxacum, which exhibits multiple pharmacological activities and protective effects. However, the underlying influence and mechanism of its use against kidney damage caused from zearalenone (ZEA) remain unexplored. The ZEA-induced kidney damage model of mice was established by feeding diets containing ZEA (2 mg/kg), and taraxasterol (5 and 10 mg/kg) was administered by gavage for 28 days. Results demonstrated taraxasterol increased average daily gain (ADG) and average daily feed intake (ADFI), reduced feed-to-gain ratio (F/G) and kidney index of mice induced by ZEA. Taraxasterol alleviated histopathological changes of kidney, reduced ZEA residue and the levels of blood urea nitrogen (BUN), uric acid (UA), and creatinine (CRE). Concurrently, taraxasterol reduced the contents of oxidative stress indicator reactive oxygen species (ROS) and malondialdehyde (MDA), and increased the activities of antioxidant enzymes catalase (CAT), total superoxide dismutase (T-SOD), and glutathione peroxidase (GSH-Px). Further, taraxasterol up-regulated the mRNA and protein expression of nuclear factor erythroid-2-related factor 2 (Nrf2), GSH-Px, NAD(P)H quinone oxidoreductase 1 (NQO1), and heme oxygenase-1 (HO-1), and down-regulated the mRNA and protein expression of KELCH like ECH associated protein (Keap1) in Nrf2/Keap1 pathway. Taraxasterol down-regulated the mRNA and protein expression of immunoglobulin binding protein (Bip), C/EBP homologous protein (CHOP), Bcl-2 associated X (Bax), cysteine protease (Caspase)-12, and Caspase-3, and up-regulated B-cell lymphoma 2 (Bcl-2) expression in endoplasmic reticulum stress pathway. This study suggests that taraxasterol attenuates ZEA-induced mouse kidney damage through the modulation of Nrf2/Keapl pathway to play antioxidant role and endoplasmic reticulum stress pathway to enhance anti-apoptotic ability. It will provide a basis for taraxasterol as a potential drug to prevent and treat ZEA-induced kidney damage.