Inter- and trans-generational impacts of real-world PM2.5 exposure on male-specific primary hypogonadism.

Exposure to PM2.5, a harmful type of air pollution, has been associated with compromised male reproductive health; however, it remains unclear whether such exposure can elicit transgenerational effects on male fertility. Here, we aim to examine the effect of paternal exposure to real-world PM2.5 on the reproductive health of male offspring. We have observed that paternal exposure to real-world PM2.5 can lead to transgenerational primary hypogonadism in a sex-selective manner, and we have also confirmed this phenotype by using an external model. Mechanically, we have identified small RNAs (sRNAs) that play a critical role in mediating these transgenerational effects. Specifically, miR6240 and piR016061, which are present in F0 PM sperm, regulate intergenerational transmission by targeting Lhcgr and Nsd1, respectively. We have also uncovered that piR033435 and piR006695 indirectly regulate F1 PM sperm methylation by binding to the 3'-untranslated region of Tet1 mRNA. The reduced expression of Tet1 resulted in hypermethylation of several testosterone synthesis genes, including Lhcgr and Gnas, impaired Leydig cell function and ultimately led to transgenerational primary hypogonadism. Our findings provide insights into the mechanisms underlying the transgenerational effects of paternal PM2.5 exposure on reproductive health, highlighting the crucial role played by sRNAs in mediating these effects. The findings underscore the significance of paternal pre-conception interventions in alleviating the adverse effects of environmental pollutants on reproductive health.

Establishing national reference materials for genetic testing of cytochrome P450.

OBJECTIVES: Reference materials for in-vitro diagnostic reagents play a critical role in determining the quality of reagents and ensuring the accuracy of clinical test results. This study aimed to establish a national reference material (NRM) for detecting cytochrome P450 (CYP) genes related to drug metabolism by screening databases on the Chinese population to identify CYP gene polymorphism characteristics. METHODS: To prepare the NRM, we used DNA extracted from healthy human immortalized B lymphoblastoid cell lines as the raw material. Samples of these cell lines were obtained from the Chinese Population PGx Gene Polymorphism Biobank. Further, we used Sanger sequencing, next-generation sequencing, and commercial assay kits to validate the polymorphic genotypes. RESULTS: Among the CYP superfamily genes, we confirmed 24 riboswitch loci related to drug metabolism, with evidence levels of 1A, 2A, 3, and 4. We confirmed the polymorphic loci and validated their genotypes using various sequencing techniques. Our results were consistent with the polymorphism information of samples obtained from the biobank, thus demonstrating high precision and stability of the established NRM. CONCLUSION: An NRM (360 056-202 201) for CYP genetic testing covering 24 loci related to drug metabolism was established and approved to assess in-vitro diagnostic reagents containing CYP family gene polymorphisms and perform clinical inter-room quality evaluations.

Laparoscopic hepatectomy for hepatocellular adenoma using the hepatic vein as anatomic markers,How I do it.(with video).

TECHNIQUE: Hepatocellular adenoma (HCA) is a benign monoclonal tumour that originates from mature hepatocytes.Liver resection is recommended in case of overt malignant transformation to hepatocellular carcinoma.However, hepatobiliary surgeries are technically challenging in patients with giant HCA (GHCA) owing to the risk of catastrophic intraoperative bleeding and difficulty with its control during laparoscopic treatment. We present a technical note on the utilization of the hepatic vein as anatomical landmarks for laparoscopic removal of giant hepatic glands, without intraoperative ultrasonography and with the aid of an augmented reality navigation system during surgery. RESULTS: This video shows aA 37-year-old man was recommended treatment for a progressively increasing HCA (from 3 to 10 cm in a year) involving the right hepatic vein (RHV), inferior vena cava (IVC) and middle hepatic vein (MHV), resulting in the invisibility of the above intrahepatic anatomic markers in CT. Laparoscopic hepatectomy was performed using the hepatic vein as anatomic markers in a treatment centre specialising in minimally invasive surgeries. The procedure involved fully mobilising the right liver, transecting the parenchyma along the demarcation line in the caudal-to-cranial direction, exposing the involved caudal MHV, isolating and transecting the involved RHV and preserving the integrity of the involved IVC. CONCLUSIONS: Laparoscopic hepatectomy for intractable GHCA using the involved intrahepatic anatomic markers is feasible and effective. It reduces pre-operative haemorrhage and open conversion rates while maximising postoperative hepatic function.

Clinicopathological role of Cyclin A2 in uterine corpus endometrial carcinoma: Integration of tissue microarrays and ScRNA-Seq.

BACKGROUND: The comprehensive expression level and potential molecular role of Cyclin A2 (CCNA2) in uterine corpus endometrial carcinoma (UCEC) remains undiscovered. METHODS: UCEC and normal endometrium tissues from in-house and public databases were collected for investigating protein and messenger RNA expression of CCNA2. The transcription factors of CCNA2 were identified by the Cistrome database. The prognostic significance of CCNA2 in UCEC was evaluated through univariate and multivariate Cox regression as well as Kaplan-Meier curve analysis. Single-cell RNA-sequencing (scRNA-seq) analysis was performed to explore cell types in UCEC, and the AUCell algorithm was used to investigate the activity of CCNA2 in different cell types. RESULTS: A total of 32 in-house UCEC and 30 normal endometrial tissues as well as 720 UCEC and 165 control samples from public databases were eligible and collected. Integrated calculation showed that the CCNA2 expression was up-regulated in the UCEC tissues (SMD = 2.43, 95% confidence interval 2.23∼2.64). E2F1 and FOXM1 were identified as transcription factors due to the presence of binding peaks on transcription site of CCNA2. CCNA2 predicted worse prognosis in UCEC. However, CCNA2 was not an independent prognostic factor in UCEC. The scRNA-seq analysis disclosed five cell types: B cells, T cells, monocytes, natural killer cells, and epithelial cells in UCEC. The expression of CCNA2 was mainly located in B cells and T cells. Moreover, CCNA2 was active in T cells and B cells using the AUCell algorithm. CONCLUSION: CCNA2 was up-regulated and mainly located in T cells and B cells in UCEC. Overexpression of CCNA2 predicted unfavorable prognosis of UCEC.

[Meta-analysis and trial sequential analysis of Tanreqing Injection in treatment of severe pneumonia in elderly].

This study aimed to systematically evaluate the effectiveness and safety of Tanreqing Injection in the treatment of severe pneumonia in the elderly. Eighteen randomized controlled trials(RCTs) involving 1 457 elderly patients with severe pneumonia were included in the study after conducting searches in both Chinese and English databases as well as clinical trial registration platforms. The quality of the included studies was assessed using the Cochrane risk of bias assessment tool. Meta-analysis were conducted using RevMan 5.4 and Stata 17 software, and trial sequential analysis(TSA) was performed using TSA 0.9.5.10 beta software. Meta-analysis results showed that compared with conventional western medicine treatment, Tanreqing Injection + conventional western medical significantly improved the clinical effectiveness in elderly patients with severe pneumonia(RR=1.26, 95%CI[1.20, 1.32], P<0.000 01), arterial oxygen partial pressure(SMD=6.23, 95%CI[3.29, 9.18], P<0.000 1), oxygenation index(SMD=11.72, 95%CI[4.41, 19.04], P=0.002), reduce procalcitonin(SMD=-6.16, 95%CI[-8.10,-4.21], P<0.000 01), C-reactive protein(SMD=-8.50, 95%CI[-11.05,-5.96], P<0.000 01), white blood cell count(SMD=-4.56, 95%CI[-5.73,-3.39], P<0.000 01), and shortened the duration of fever(SMD=-3.12, 95%CI[-4.61,-1.63], P<0.000 1), cough(SMD=-4.84, 95%CI[-6.90,-2.79], P<0.000 01), lung rales(SMD=-0.99, 95%CI[-1.54,-0.44], P=0.000 4), and mechanical ventilation time(SMD=-3.26, 95%CI[-5.03,-1.50], P=0.000 3), increase CD4~+ T-cell levels(SMD=6.73, 95%CI[5.23, 8.23], P<0.000 01) and CD8~+ T-cell levels(SMD=7.47, 95% CI[5.32, 9.61], P<0.000 01) with no significant adverse reactions. TSA confirmed the stability and reliability of the results related to clinical effectiveness. This study suggests that Tanreqing Injection, as a Chinese medicinal preparation, has a significant therapeutic effect and good safety profile in the treatment of severe pneumonia in elderly patients. Due to the limited quality of the included studies, high-quality RCT is still needed to provide evidence support for the above conclusions.

An all-inclusive model for predicting invasive bacterial infection in febrile infants age 7-60 days.

BACKGROUND: Invasive bacterial infections (IBIs) in febrile infants are rare but potentially devastating. We aimed to derive and validate a predictive model for IBI among febrile infants age 7-60 days. METHODS: Data were abstracted retrospectively from electronic records of 37 emergency departments (EDs) for infants with a measured temperature >=100.4 F who underwent an ED evaluation with blood and urine cultures. Models to predict IBI were developed and validated respectively using a random 80/20 dataset split, including 10-fold cross-validation. We used precision recall curves as the classification metric. RESULTS: Of 4411 eligible infants with a mean age of 37 days, 29% had characteristics that would likely have excluded them from existing risk stratification protocols. There were 196 patients with IBI (4.4%), including 43 (1.0%) with bacterial meningitis. Analytic approaches varied in performance characteristics (precision recall range 0.04-0.29, area under the curve range 0.5-0.84), with the XGBoost model demonstrating the best performance (0.29, 0.84). The five most important variables were serum white blood count, maximum temperature, absolute neutrophil count, absolute band count, and age in days. CONCLUSION: A machine learning model (XGBoost) demonstrated the best performance in predicting a rare outcome among febrile infants, including those excluded from existing algorithms. IMPACT: Several models for the risk stratification of febrile infants have been developed. There is a need for a preferred comprehensive model free from limitations and algorithm exclusions that accurately predicts IBIs. This is the first study to derive an all-inclusive predictive model for febrile infants aged 7-60 days in a community ED sample with IBI as a primary outcome. This machine learning model demonstrates potential for clinical utility in predicting IBI.

Repurposing AS1411 for constructing ANM-PROTACs.

Proteolysis-targeting chimeras (PROTACs) are heterobifunctional molecules consisting of two ligands joined by a linker, enabling them to simultaneously bind with an E3 ligase and a protein of interest (POI) and trigger proteasomal degradation of the POI. Limitations of PROTAC include lack of potent E3 ligands, poor cell selectivity, and low permeability. AS1411 is an antitumor aptamer specifically recognizing a membrane-nucleus shuttling nucleolin (NCL). Here, we repurpose AS1411 as a ligand for an E3 ligase mouse double minute 2 homolog (MDM2) via anchoring the NCL-MDM2 complex. Then, we construct an AS1411-NCL-MDM2-based PROTAC (ANM-PROTAC) by conjugating AS1411 with large-molecular-weight ligands for "undruggable" oncogenic STAT3, c-Myc, p53-R175H, and AR-V7. We show that the ANM-PROTAC efficiently penetrates tumor cells, recruits MDM2 and degrades the POIs. The ANM-PROTAC achieves tumor-selective distribution and exhibits excellent antitumor activity with no systemic toxicity. This is a PROTAC with built-in tumor-targeting and cell-penetrating capacities.

Astragalus polysaccharide attenuates diabetic nephropathy by reducing apoptosis and enhancing autophagy through activation of Sirt1/FoxO1 pathway.

OBJECTIVE: Diabetic nephropathy (DN) is the leading cause of end-stage renal disease in diabetic patients. Astragalus polysaccharide (APS) is a natural active ingredient in Astragalus membranaceus with anti-hypertensive and anti-oxidative properties. This study aimed to explore the protective roles of APS and its underlying mechanisms in DN. METHODS: After the establishment of a rat model of DN by a high-fat diet and treatment with 30 mg/kg streptozotocin (STZ), the effects of 100 mg/kg APS on the levels of serum creatinine, blood urea nitrogen, blood glucose, and urinary albumin-to-creatinine ratio were measured. Histopathological alterations in renal tissues, renal cell apoptosis, renal inflammation, and oxidative stress were examined. The impacts of 0-200 µg/mL APS on the viability and apoptosis in high glucose (HG)-stimulated podocytes were measured by Cell Counting Kit-8 assays and flow cytometry, respectively. The expression of genes was tested by immunoblotting, quantitative real-time PCR, and immunofluorescence staining. RESULTS: APS enhanced the expression of podocin and nephrin, increased viability, and reduced apoptosis in HG-induced podocytes. APS treatment abrogated high glucose-mediate suppression of autophagy in podocytes by activating the Sirt1/FoxO1 pathway. The Sirt1 inhibitor EX-527 eliminated the ameliorative effects of APS on renal dysfunction and renal tissue damage, as well as the inhibitory effects of APS on oxidative stress, inflammation, and apoptosis in DN rats. Moreover, EX-527 inhibited APS-induced autophagy activation in DN rats. CONCLUSION: APS mitigated DN under hyperglycemic conditions by activating the Sirt1/FoxO1 autophagy pathway, suggesting that APS is a promising agent for DN treatment.

EPA and DHA Differentially Improve Insulin Resistance by Reducing Adipose Tissue Inflammation - Targeting GPR120/PPARγ Pathway.

Insulin resistance (IR) is a global health challenge, often initiated by dysfunctional adipose tissue. Eicosapentaenoic acid (EPA) and Docosahexaenoic acid (DHA) may have different effects on IR, but the mechanisms are unknown. This study aims to evaluate the protective effect of EPA and DHA against IR in a high-fat diet (HFD) mice model and investigate whether EPA and DHA alter IR modulate the G-protein-poupled receptor 120/peroxisome proliferator-activated receptor γ (GPR120/PPARγ) pathway in macrophages and adipocytes, which may affect IR in adipocytes. The findings of this study show that 4% DHA had a better effect in improving IR and reducing inflammatory cytokines in adipose tissue of mice. Additionally, in the cell experiment, the use of AH7614 (a GPR120 antagonist) inhibited the glucose consumption increase and the increasable expression of PPARγ and insulin signaling molecules mediated by DHA in adipocytes. Furthermore, GW9662 (a PPARγ antagonist) hindered the upregulation of glucose consumption and insulin signaling molecule expression induced by EPA and DHA in adipocytes. DHA exhibited significant effects in reducing the number of migrated cells and inflammation. The compounds AH7614 and GW9662 hindered the suppressive effects of EPA and DHA on macrophage-induced IR in adipocytes. These findings suggest that DHA has a stronger potential in improving IR in adipocytes through the GPR120/PPARγ pathway in macrophages, when compared to EPA.

Protective effects of COVID-19 vaccination in splenectomized patients with immune thrombocytopenia.

Splenectomy is an effective treatment for immune thrombocytopenia (ITP). The effect of COVID-19 vaccination on splenectomized patients with ITP during the COVID-19 pandemic has not been reported. Therefore, this study aimed to investigate the effect of COVID-19 vaccination on clinical outcomes in these patients. This was a longitudinal study of splenectomized patients with ITP. A total of 191 splenectomized patients were included in this study. After a median follow-up of 114 months, 146 (76.4%) patients had a sustained response to splenectomy. During COVID-19 infection, vaccinated patients showed a lower risk of severe infections (odds ratio [OR], 0.13; 95% confidence interval [CI]: 0.05-0.36; p < 0.001), hospitalization (OR, 0.13; 95% CI, 0.04-0.48; p = 0.002), and ITP exacerbation (OR, 0.16; 95% CI, 0.04-0.67; p = 0.012). These findings indicate that COVID-19 vaccination plays a protective role in splenectomized patients with ITP.

Dose-effect of exercise intervention on heart rate variability of acclimatized young male lowlanders at 3,680 m.

This study investigated whether exercise could improve the reduced HRV in an environment of high altitude. A total of 97 young, healthy male lowlanders living at 3,680 m for >1 year were recruited. They were randomized into four groups, of which three performed-low-, moderate-, and high-intensity (LI, MI, HI) aerobic exercise for 4 weeks, respectively. The remaining was the control group (CG) receiving no intervention. For HI, compared to other groups, heart rate (p = 0.002) was significantly decreased, while standard deviation of RR intervals (p < 0.001), SD2 of Poincaré plot (p = 0.046) and the number of successive RR interval pairs that differ by > 50 ms divided by total number of RR (p = 0.032), were significantly increased after intervention. For MI, significantly increase of trigonometric interpolation in NN interval (p = 0.016) was observed after exercise. Further, a decrease in systolic blood pressure (SBP) after high-intensity exercise was found significantly associated with an increase in SD2 (r = - 0.428, p = 0.042). These results indicated that there was a dose effect of different intensities of aerobic exercise on the HRV of acclimatized lowlanders. Moderate and high-intensity aerobic exercise would change the status of the autonomic nervous system (ANS) and decrease the blood pressure of acclimatized lowlanders exposed to high altitude.

Imaging the intracellular refractive index distribution (IRID) for dynamic label-free living colon cancer cells via circularly depolarization decay model (CDDM).

Label-free detection of intracellular substances for living cancer cells remains a significant hurdle in cancer pathogenesis research. Although the sensitivity of light polarization to intracellular substances has been validated, current studies are predominantly focused on tissue lesions, thus label-free detection of substances within individual living cancer cells is still a challenge. The main difficulty is to find specific detection methods along with corresponding characteristic parameters. With refractive index as an endogenous marker of substances, this study proposes a detection method of intracellular refractive index distribution (IRID) for label-free living colon cancer (LoVo) cells. Utilizing the circular depolarization decay model (CDDM) to calculate the degree of circular polarization (DOCP) modulated by the cell allows for the derivation of the IRID on the focal plane. Experiments on LoVo cells demonstrated the refractive index of single cell can be accurately and precisely measured, with precision of 10-3 refractive index units (RIU). Additionally, chromatin content during the interphases (G1, S, G2) of cell cycle was recorded at 56.5%, 64.4%, and 71.5%, respectively. A significantly finer IRID can be obtained compared to the phase measurement method. This method is promising in providing a dynamic label-free intracellular substances detection method in cancer pathogenesis studies.

Correlation between plasma lipoprotein-associated phospholipase A2 levels and risk of ischaemic stroke recurrence by gender in the Chinese population.

OBJECTIVE: To investigate the correlation between gender differences in plasma lipoprotein phospholipase A2 (Lp-PLA2) levels and the risk of recurrent stroke in patients with acute ischaemic stroke in China. METHODS: We conducted a prospective follow-up study that included baselineLp-PLA2 levels and NIH Stroke Scale (NIHSS) scores in patients with ischaemic stroke upon admission. The diagnostic efficacy of the baseline Lp-PLA2 level for stroke recurrence was evaluated. And Kaplan‒Meier method was used to analyse the difference in the risk of recurrent stroke between these two groups among males and females. A paired t test was used to analyse the difference in Lp-PLA2 levels in male and female patients after follow-up. RESULTS: Baseline plasma Lp-PLA2 was higher in men and women with recurrent stroke than in those without recurrent stroke. The correlation between baseline Lp-PLA2 and neurological impairment was higher in female than male stroke patients (R = 0.338 and 0.253, respectively). Although weakly correlated with neurological impairment, baseline Lp-PLA2 was more effective in predicting recurrent stroke (AUC = 0.705 in men, 0.788 in women). A Cox model was used to compare the risk of stroke between the high- and low-Lp-PLA2 groups (OR = 3.98 in men, 2.61 in women). According to the follow-up time of 6 months as the node, Lp-PLA2 will give different risk indicators. CONCLUSION: Elevated plasma Lp-PLA2 is an independent risk factor for recurrent ischaemic stroke but is not strongly associated with the degree of cerebral damage. The predictive value of baseline Lp-PLA2 for stroke recurrence risk was higher in females than in males.

Co-Delivery of Astaxanthin and siTGF-ß1 via Ionizable Liposome Nanoparticles for Improved Idiopathic Pulmonary Fibrosis Therapy.

Alleviating the injury of type II alveolar epithelial cells (AEC 2s) and inhibiting the activation and differentiation of fibroblasts are significant for improving the therapeutic effect of idiopathic pulmonary fibrosis (IPF). To this aim, ionizable liposome nanoparticles (ASNPs) coloaded with antioxidant drug astaxanthin (AST) and small interfering RNA targeting transforming growth factor ß1 (siTGF-ß1) were developed for enhanced IPF therapy. ASNPs showed high loading and intracellular delivery efficiency for AST and siTGF-ß1. After the injection of ASNPs in an IPF mice model, the loaded AST largely scavenged reactive oxygen species (ROS) in the diseased lung to reduce AEC2 apoptosis, thereby ensuring the integrity of the alveolar epithelium. Meanwhile, siTGF-ß1, delivered by ASNPs, significantly silenced the expression of TGF-ß1 in fibroblasts, inhibiting the differentiation of fibroblasts into myofibroblasts as well as reducing the excessive deposition of extracellular matrix (ECM). The combined use of the two drugs exhibited an excellent synergistic antifibrotic effect and was conducive to minimizing alveolar epithelial damage. This work provides a codelivery strategy of AST and siTGF-ß1, which shows great promise for the treatment of IPF by simultaneously reducing alveolar epithelial damage and inhibiting fibroblast activation.

Key Roles of Gli1 and Ihh Signaling in Craniofacial Development.

The Hedgehog (Hh) signaling pathway orchestrates its influence through a dynamic interplay of Hh proteins, the cell surface receptor Ptch1, Smo, and Gli transcription factors, contributing to a myriad of developmental events. Indian Hedgehog (Ihh) and Gli zinc finger transcription factor 1 (Gli1) play crucial roles in developmental regulation within the Hh signaling pathway. Ihh regulates chondrocyte proliferation, differentiation, and bone formation, impacting the development of cranial bones, cartilage, and the temporomandibular joint (TMJ). Losing Ihh results in cranial bone malformation, decreased ossification, and affects the formation of cranial base cartilage unions, TMJ condyles, and joint discs. Gli1 is predominantly expressed during early craniofacial development, and Gli1+ cells are identified as the primary mesenchymal stem cells (MSCs) for craniofacial bones, crucial for cell differentiation and morphogenesis. Additionally, a complex mutual regulatory mechanism exists between Gli1 and Ihh, ensuring the normal function of the Hh signaling pathway by directly or indirectly regulating each other's expression levels. And the interaction between Ihh and Gli1 significantly impacts the normal development of craniofacial tissues.This review summarizes the pivotal roles of Gli1 and Ihh in the intricate landscape of mammalian craniofacial development, and outlines the molecular regulatory mechanisms and intricate interactions governing the growth of bone and cartilage exhibited by Gli1 and Ihh, which Provides new insights into potential therapeutic strategies for related diseases or researches of tissue regeneration.

Full endoscopic laminotomy decompression versus anterior cervical discectomy and fusion for the treatment of single-segment cervical spinal stenosis: a retrospective, propensity score-matched study.

OBJECTIVE: Anterior cervical discectomy and fusion (ACDF) is the standard procedure for the treatment of cervical spinal stenosis (CSS), but complications such as adjacent segment degeneration can seriously affect the long-term efficacy. Currently, posterior endoscopic surgery has been increasingly used in the clinical treatment of CSS. The aim of this study was to compare the clinical outcomes of single-segment CSS patients who underwent full endoscopic laminotomy decompression or ACDF. METHODS: 138 CSS patients who met the inclusion criteria from June 2018 to August 2020 were retrospectively analyzed and divided into endoscopic and ACDF groups. The propensity score matching (PSM) method was used to adjust the imbalanced confounding variables between the groups. Then, perioperative data were recorded and clinical outcomes were compared, including functional scores and imaging data. Functional scores included Visual Analog Scale of Arms (A-VAS) and Neck pain (N-VAS), Japanese Orthopedic Association score (JOA), Neck Disability Index (NDI), and imaging data included Disc Height Index (DHI), Cervical range of motion (ROM), and Ratio of grey scale (RVG). RESULTS: After PSM, 84 patients were included in the study and followed for 24-30 months. The endoscopic group was significantly superior to the ACDF group in terms of operative time, intraoperative blood loss, incision length, and hospital stay (P < 0.001). Postoperative N-VAS, A-VAS, JOA, and NDI were significantly improved in both groups compared with the preoperative period (P < 0.001), and the endoscopic group showed better improvement at 7 days postoperatively (P < 0.05). The ROM changes of adjacent segments were significantly larger in the ACDF group at 12 months postoperatively and at the last follow-up (P < 0.05). The RVG of adjacent segments showed a decreasing trend, and the decrease was more marked in the ACDF group at last follow-up (P < 0.05). According to the modified MacNab criteria, the excellent and good rates in the endoscopic group and ACDF group were 90.48% and 88.10%, respectively, with no statistically significant difference (P > 0.05). CONCLUSION: Full endoscopic laminotomy decompression is demonstrated to be an efficacious alternative technique to traditional ACDF for the treatment of single-segment CSS, with the advantages of less trauma, faster recovery, and less impact on cervical spine kinematics and adjacent segmental degeneration.