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Full-endoscopic lumbar interbody fusion (FELIF) is a critical yet challenging procedure. However, extensive analyses of discectomy and cartilage endplate preparation techniques are limited. This can be attributed to the lack of universal protocols owing to diverse surgical practices and equipment preferences. Therefore, this narrative review presents a comprehensive overview of discectomy and cartilage endplate preparation techniques in FELIF. A literature search of the PubMed, Embase, and Google Scholar databases in December 2023 retrieved 490 studies, of which 53 met the predefined inclusion criteria, and 1373 patients were included in the analyses. Spinal endoscopic disc and cartilage endplate removal can be categorized into 2 main types: removal under direct endoscopic visualization and removal under radiographic guidance with the protection of a working sheath following the endoscope's removal. Removal under direct visualization ensures the safety and precision of the procedure. Radiographic guidance can enhance the efficiency of the removal process. Specially designed instruments can be utilized through the narrow working channels of spinal endoscopes for the scraping surgery. Moreover, many traditional spinal endoscopic instruments, through specific techniques and manipulations, can also aid in cartilage removal. The approaches and techniques vary significantly among physicians, but overall, these instruments and techniques aim to achieve a safe and efficient disc-scraping outcome. Thus, this review may offer a comprehensive guidance to surgeons in selecting the most efficient practices for FELIF. Uniform procedural protocols are needed to ensure broader adoption and standardized practice., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Meiosis is the process of producing haploid gametes through a series of complex chromosomal events and the coordinated action of various proteins. The mitochondrial protease complex (ClpXP), which consists of caseinolytic mitochondrial matrix peptidase X (ClpX) and caseinolytic protease P (ClpP) and mediates the degradation of misfolded, damaged, and oxidized proteins, is essential for maintaining mitochondrial homeostasis. ClpXP has been implicated in meiosis regulation, but its precise role is currently unknown. In this study, we engineered an inducible male germ cell-specific knockout caseinolytic mitochondrial matrix peptidase X ( ClpxcKO ) mouse model to investigate the function of ClpX in meiosis. We found that disrupting Clpx in male mice induced germ cell apoptosis and led to an absence of sperm in the epididymis. Specifically, it caused asynapsis of homologous chromosomes and impaired meiotic recombination, resulting in meiotic arrest in the zygotene-to-pachytene transition phase. The loss of ClpX compromised the double-strand break (DSB) repair machinery by markedly reducing the recruitment of DNA repair protein RAD51 homolog 1 (RAD51) to DSB sites. This dysfunction may be due to an insufficient supply of energy from the aberrant mitochondria in ClpxcKO spermatocytes, as discerned by electron microscopy. Furthermore, ubiquitination signals on chromosomes and the expression of oxidative phosphorylation subunits were both significantly attenuated in ClpxcKO spermatocytes. Taken together, we propose that ClpX is essential for maintaining mitochondrial protein homeostasis and ensuring homologous chromosome pairing, synapsis, and recombination in spermatocytes during meiotic prophase I., (Copyright © 2023 Copyright: © The Author(s)(2023).)

Aim: To explore the latest application of artificial intelligence (AI) in optical coherence tomography (OCT) images, and to analyze the current research status of AI in OCT, and discuss the future research trend., Methods: On June 1, 2023, a bibliometric analysis of the Web of Science Core Collection was performed in order to explore the utilization of AI in OCT imagery. Key parameters such as papers, countries/regions, citations, databases, organizations, keywords, journal names, and research hotspots were extracted and then visualized employing the VOSviewer and CiteSpace V bibliometric platforms., Results: Fifty-five nations reported studies on AI biotechnology and its application in analyzing OCT images. The United States was the country with the largest number of published papers. Furthermore, 197 institutions worldwide provided published articles, where University of London had more publications than the rest. The reference clusters from the study could be divided into four categories: thickness and eyes, diabetic retinopathy (DR), images and segmentation, and OCT classification., Conclusion: The latest hot topics and future directions in this field are identified, and the dynamic evolution of AI-based OCT imaging are outlined. AI-based OCT imaging holds great potential for revolutionizing clinical care., (International Journal of Ophthalmology Press.)

Background and Objective: Cerebrocardiac syndrome (CCS) is a severe complication of severe traumatic brain injury (sTBI) that carries high mortality and disability rates. Early identification of CCS poses a significant clinical challenge. The main objective of this study was to investigate potential risk factors associated with the development of secondary CCS in patients with sTBI. It was hypothesized that elevated right heart Tei index (TI), lower Glasgow Coma Scale (GCS) scores, and elevated cardiac troponin-I (cTnI) levels would independently contribute to the occurrence of CCS in sTBI patients., Methods: A retrospective cohort study was conducted to identify risk factors for CCS secondary to sTBI. One hundred and fifty-five patients were enrolled with sTBI admitted to the hospital between January 2016 and December 2020 and divided them into a CCS group ( n = 75) and a non-CCS group ( n = 80) based on the presence of CCS. This study involved the analysis and comparison of clinical data from two patient groups, encompassing demographic characteristics, peripheral oxygen saturation (SPO2), neuron-specific enolase (NSE), cardiac troponin-I (cTnI), N-terminal pro-brain natriuretic peptide (NT-proBNP), optic nerve sheath diameter (ONSD), cardiac ultrasound, acute physiology and chronic health evaluation (APACHE II) scores, and GCS scores and so on. Multivariate logistic regression was employed to identify independent risk factors for CCS, and receiver operating characteristic (ROC) curves were used to assess their predictive value for CCS secondary to sTBI., Results: The study revealed that 48.4% of sTBI patients developed secondary CCS. In the multivariate analysis model 1 that does not include NT-proBNP and cTnI, ONSD (OR = 2.582, 95% CI: 1.054-6.327, P = 0.038), right heart Tei index (OR = 2.81, 95% CI: 1.288-6.129, P = 0.009), and GCS (OR = 0.212, 95% CI: 0.086-0.521, P = 0.001) were independent risk factors for secondary CCS in sTBI patients. In multivariate analysis model 2 that includes NT-proBNP and cTnI, cTnI (OR = 27.711, 95%CI: 3.086-248.795, P = 0.003), right heart Tei index (OR = 2.736, 95% CI: 1.056-7.091, P = 0.038), and GCS (OR = 0.147, 95% CI: 0.045-0.481, P = 0.002) were independent risk factors for secondary CCS in sTBI patients. The area under the ROC curve for ONSD, Tei index, GCS, and cTnI were 0.596, 0.613, 0.635, and 0.881, respectively. ONSD exhibited a positive predictive value (PPV) of 0.704 and a negative predictive value (NPV) of 0.634. The Tei index demonstrated a PPV of 0.624 and an NPV of 0.726, while GCS had a PPV of 0.644 and an NPV of 0.815. On the other hand, cTnI exhibited a significantly higher PPV of 0.936 and an NPV of 0.817. These findings indicate that the Tei index, GCS score, and cTnI possess certain predictive value for secondary CCS in patients with sTBI., Conclusions: The study provides valuable insights into the identification of independent risk factors for CCS secondary to sTBI. The findings highlight the significance of right heart Tei index, GCS score, and cTnI as potential predictive factors for CCS in sTBI patients. Further larger-scale studies are warranted to corroborate these findings and to provide robust evidence for the development of early intervention strategies aimed at reducing the incidence of CCS in this patient population., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Wang, Gao, Zhuo, Weng, Feng, Lin, Lin and Huang.)

Objective: Chlordimeform is a chemical pesticide that is highly carcinogenic and toxic. The purpose of this study was to establish an enzyme-linked immunosorbent assay (ELISA) method for the detection of chlordimeform in aquaculture and fish farming., Methods: Chlordimeform was coupled with bovine serum albumin (BSA) and ovalbumin (OVA) as carrier proteins. A chlordimeform-BSA conjugate was used as an immunogen, and chlordimeform-OVA was used as a coating antigen. Chlordimeform-BSA was used to immunize rabbits, and a polyclonal antibody was prepared. An indirect competitive enzyme-linked immunosorbent assay (IC-ELISA) was established to detect chlordimeform., Results: The working range of the established IC-ELISA method for chlordimeform detection was 1-20 ng/mL. The IC 50 was 3.126 ng/mL, and the lower limit of detection (LOD) of chlordimeform was 0.637 ng/mL. The recovery of chlordimeform from spiked water samples ranged from 81% to 107%., Conclusion: An anti-chlordimeform polyclonal antibody was successfully developed, and a novel IC-ELISA was established to detect chlordimeform in aquaculture.

The problem of adolescent online gaming addiction is related to individual-level characteristics and the influence of the family environment. The present study explores the potential role of adolescents' time management tendency in mediating the relationship between parenting style and adolescent internet gaming disorder (IGD). Responses from a total of 357 Chinese high school students were collected for a Pathological Video-Game Use Questionnaire, Simplified Parenting Styles Scale, and Time Management Tendency Scale. Overall, participants reported moderate use of online games (Mean = 1.41; SD = 0.41), lower than the median value of 2 on a three-point scale. In terms of the mediating role of adolescents' time management tendency, full meditation was observed for the relationship between the parenting style factor of "parents' emotional warmth" for both mothers and fathers and internet gaming disorder. The results highlight the benefits of emotional warmth in supporting self-efficacy, self-control, and autonomy through the promotion of time management, which is an important protective factor for IGD and can serve as a mediating personality variable. Although non-significant in the complete model, over-protection and rejection by parents should also be cautiously considered as potential risk factors related to addiction.

The ganglioneuroma is a benign tumor originating from sympathetic ganglion cells.It often locates in the posterior mediastinum,retroperitoneum,and adrenal medulla.The intraspinal ganglioneuromas is relatively rare in clinical practice,which mainly locates in the cervical and thoracolumbar segments.A patient with main symptom of cough was examined by magnetic resonance imaging before operation in our center.Intraspinal ganglioneuromas was confirmed in the left intervertebral cavity area.Total resection of the tumor via the posterior median approach was performed.HE staining showed the mature ganglion cells were scattered.The patient was followed up for three months and no tumor recurrence occured.

A platinum(ii) complex containing an aminophosphonate ligand preferentially accumulates in the endoplamic reticulum (ER) in association with potent ER stress and reactive oxygen species generation, followed by the activation of damage-associated molecular pattern signals and immune responses. Importantly, the Pt complex exhibits potent anti-tumour activities in two independent mouse models via an immunogenic cell death pathway.

Meiosis is a specialized type of cell division that creates haploid germ cells and ensures their genetic diversity through homologous recombination. We show that the H3K4me3 reader ZCWPW1 is specifically required for meiosis prophase I progression in male but not in female germ cells in mice. Loss of Zcwpw1 in male mice caused a complete failure of synapsis, resulting in meiotic arrest at the zygotene to pachytene stage, accompanied by incomplete DNA double-strand break repair and lack of crossover formation, leading to male infertility. In oocytes, deletion of Zcwpw1 only somewhat slowed down meiosis prophase I progression; Zcwpw1 -/- oocytes were able to complete meiosis, and Zcwpw1 -/- female mice had normal fertility until mid-adulthood. We conclude that the H3K4me3 reader ZCWPW1 is indispensable for meiosis synapsis in males but is dispensable for females. Our results suggest that ZCWPW1 may represent a previously unknown, sex-dependent epigenetic regulator of germ cell meiosis in mammals.

Severe reduction in the β-cell number (collectively known as the β-cell mass) contributes to the development of both type 1 and type 2 diabetes. Recent pharmacological studies have suggested that increased pancreatic β-cell proliferation could be due to specific inhibition of adenosine kinase (ADK). However, genetic evidence for the function of pancreatic β-cell ADK under physiological conditions or in a pathological context is still lacking. In this study, we crossed mice carrying LoxP-flanked Adk gene with Ins2-Cre mice to acquire pancreatic β -cell ADK deficiency (Ins2-Cre ± Adk fl/fl ) mice. Our results revealed that Ins2-Cre +/- Adk fl/fl mice showed improved glucose metabolism and β-cell mass in younger mice, but showed normal activity in adult mice. Moreover, Ins2-Cre ± Adk fl/fl mice were more resistant to streptozotocin (STZ) induced hyperglycaemia and pancreatic β-cell damage in adult mice. In conclusion, we found that ADK negatively regulates β-cell replication in young mice as well as under pathological conditions, such as STZ induced pancreatic β-cell damage. Our study provided genetic evidence that specific inhibition of pancreatic β-cell ADK has potential for anti-diabetic therapy., (© 2019 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.)

Agents with multiple modes of tumor cell death can be effective chemotherapeutic drugs. One example of a bimodal chemotherapeutic approach is an agent that can induce both apoptosis and autophagic death. Thus far, no clinical anticancer drug has been shown to simultaneously induce both these pathways. Mono-functional platinum complexes are potent anticancer drug candidates which act through mechanisms distinct from cisplatin. Here, we describe the synthesis and characterize of two mono-functional platinum complexes containing 8-substituted quinoline derivatives as ligands. In comparison to cisplatin, n-Mon-Pt-1 exhibited a greater in vitro cytotoxicity, was more effective in resistant cells and elicited a better anticancer effect. Mechanistic experiments indicate that n-Mon-Pt-1 mainly accumulates in mitochondria, and stimulates significant TrxR inhibition, ROS release and an ER stress response, ultimately resulting in a simultaneous induction of apoptosis and autophagy. Importantly, compared to cisplatin, n-Mon-Pt-1 exhibits lower acute toxicity and better anticancer activity in a murine tumor model., (Copyright © 2018. Published by Elsevier Inc.)

Objective: To determine the change pattern of olfactory function in chronic rhinosinusitis (CRS) with olfactory dysfunction after endoscopic sinus surgery (ESS), and its association with inspection scores., Study Design: Observational study., Place and Duration of Study: Second Hospital of Shandong University, China, from December 2014 to January 2016., Methodology: Thirty-four CRS with nasal polyps (CRSwNP) patients and 14 CRS without nasal polyps (CRSsNP) patients were evaluated preoperatively by T&T olfactory test, olfactory VAS test, SNOT-20score and Lund-Mackay CT score. Outcomes were re-evaluated at 1 month, 3 months and 6 months postoperatively., Results: Both olfactory and SNOT-20 scores showed significant improvement within 6 months in both CRSwNP and CRSsNP groups. Patients with anosmia in T&T test showed the largest degree of improvement. No significant recovery of olfactory dysfunction was observed at 1 month and 3 months in CRSsNP groups postoperative. In CRSwNP, the olfactory scores were correlated with the CT scores significantly (r=0.649, p<0.001; r=0.625, p<0.001). However, no correlation was found between the SNOT-20 score and olfactory score preoperatively., Conclusion: Our study has confirmed that the therapeutic effects of ESS on olfactory function last for up to 6 months, particularly in patients with CRSwNP. Although the therapeutic effects plateaued at 3 months postoperatively, the olfactory function continues to recover between 3 and 6 months.

Agents with multiple modes of tumor cell death can be effective chemotherapeutic drugs. One example of a bimodal chemotherapeutic approach is an agent that can induce both apoptosis and autophagic death. Thus far, no clinical anticancer drug has been shown to simultaneously induce both these pathways. Mono-functional platinum complexes are potent anticancer drug candidates which act through mechanisms distinct from cisplatin. Here, we describe the synthesis and characterize of two mono-functional platinum complexes containing 8-substituted quinoline derivatives as ligands, [PtL 1 Cl]Cl [L 1  = (Z)-1-(pyridin-2-yl)-N-(quinolin-8-ylmethylene) methanamine] (Mon-Pt-1) and [PtL 2 Cl]Cl [L 2  = (Z)-2-(pyridin-2-yl)-N-(quinolin-8-ylmethylene) ethanamine] (Mon-Pt-2). In comparison to cisplatin, Mon-Pt-2 exhibited a greater in vitro cytotoxicity, was more effective in resistant cells and elicited a better anticancer effect. Mechanistic experiments indicate that Mon-Pt-2 mainly accumulates in mitochondria, and stimulates significant TrxR inhibition ROS release and an ER stress response, mediated by mitochondrial dysfunction, ultimately resulting in a simultaneous induction of apoptosis and autophagy. Importantly, compared to cisplatin, Mon-Pt-2 exhibits lower acute toxicity and better anticancer activity in a murine tumor model. To the best of our knowledge, Mon-Pt-2 is the first mono-functional platinum complex inducing pro-death autophagy and apoptosis of cancer cells., (Copyright © 2018 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Agents inducing both apoptosis and autophagic death can be effective chemotherapeutic drugs. In our present work, we synthesized two organometallic gold(III) complexes harboring C^N ligands that structurally resemble tetrahydroisoquinoline (THIQ): Cyc-Au-1 (AuL 1 Cl 2 , L 1 = 3,4-dimethoxyphenethylamine) and Cyc-Au-2 (AuL 2 Cl 2 , L 2 = methylenedioxyphenethylamine). In screening their in vitro activity, we found both gold complexes exhibited lower toxicity, lower resistance factors, and better anticancer activity than those of cisplatin. The organometallic gold(III) complexes accumulate in mitochondria and induce elevated ROS and an ER stress response through mitochondrial dysfunction. These effects ultimately result in simultaneous apoptosis and autophagy. Importantly, compared to cisplatin, Cyc-Au-2 exhibits lower toxicity and better anticancer activity in a murine tumor model. To the best of our knowledge, Cyc-Au-2 is the first organometallic Au(III) compound that induces apoptosis and autophagic death. On the basis of our results, we believe Cyc-Au-2 to be a promising anticancer agent or lead compound for further anticancer drug development.

Background: To investigate the effect of adenotonsillectomy (AT) on bone development, quality of life and polysomnography evaluation in children with obstructive sleep apnea syndrome (OSA)., Methods: Preoperative and postoperative (6 months) physical examination, PSG, bone age (BA) and osteocalcin (OC) evaluation were performed on the selected OSA children (n=92) and the healthy children (n=87). The OSA children were also scored based on the OSA 18-item questionnaire. A two-year follow-up was conducted to evaluate BA and OC changes., Results: After AT, 81 (88.04%) OSA children recovered completely, eight (8.70%) achieved remarkable improvements, and three (3.26%) achieved moderate improvements. In the OSA children, postoperative OSA 18-item score and the scores of the five domains were significantly higher than preoperative ones. Compared with the preoperative, body mass index (BMI), weight for age Z-sores, height for age Z-sores, weight for height Z-sores and BMI Z-score in the OSA group 6 months after the operation were significantly increased, but no significant difference was detected between the OSA and the control group. The changes of BA and chronological age in the OSA group were significantly different from those in the control group. Two years after AT, BA between the two groups was no longer significantly different. Preoperative serum OC in the OSA group was lower than that in the control group, but increased to normal levels 6 months after AT. Correlation analysis showed serum OC levels were negatively correlated with apnea hyponea index, obstructive apnea index, arousal index, and lowest oxygen saturation., Conclusions: After AT, bone growth and development in children with OSA recovered gradually, and the serum OC levels decreased to the normal level. Therefore, preventive measures and positive treatments should be applied to minimize the negative effects of OSA in children.

Our aim was to study the changes in bone age and serum osteocalcin levels before and after adenotonsillectomy (AT) in children with obstructive sleep apnea hypopnea syndrome (OSAHS). A total of 58 OSAHS children (37 males and 21 females) with the mean age of 6.68 ± 1.11 years were enrolled and assessed by x-ray-based bone age estimation and enzyme-linked immunosorbent assay-based measurement of serum osteocalcin levels, before surgery and 6 months after AT. SPSS 19.0 software was used for statistical analysis. Our results revealed that bone age and serum osteocalcin levels in OSAHS patients were significantly lower than normal controls before AT (P < 0.05). Within 6 months after surgery, the bone age and the serum osteocalcin levels were significantly elevated in OSAHS patients (P < 0.05), compared with those before surgery. Serum osteocalcin levels and bone age are negatively correlated with apnea-hypopnea index, oxygen desaturation index, the percentage of the total recorded time spent below 90% oxygen saturation, and Epworth sleepiness scale scores (all P < 0.05). Our findings suggested that bone age and serum osteocalcin levels may be correlated with the development of OSAHS in children. AT may improve bone age and serum osteocalcin levels in OSAHS children.

The utilization of straw resources is of great significance to agricultural environmental protection and sustainable agricultural development. Based on the isolated 15 high-efficient cellulose degrading bacteria in the laboratory, the composite inoculants (JFB-1) which can effectively degrade crop straw were screened, and the effects of straw composts with the composite inoculants on soil carbon and nitrogen contents and enzyme activity were studied. The results showed that the composite inoculants could accelerate straw decomposition for 1-2 d during single fermentation period, and the organic matter contents in straw composts reached 403.5-515.1 g·kg -1 , while the ratio of carbon and nitrogen decreased from 10.53 to 15.30. The pot experiments found that the application effects of rice straw composts were generally better than those of corresponding asparagus straw composts. Compared with the control compost of rice straw, when the application amount of rice straw compost using the composite inoculants was 150 g·kg -1 , the contents of soil organic matter and total nitrogen increased by 33.5% and 7.3%, and soil urease and cellulase activities increased by 16.7% and 30.8%, respectively. Compared with no fertilization treatment, the application of straw composts could improve soil microbial community structure, and increase microbial diversity indices. When the application amount of rice straw compost using the composite inoculants was 100 g·kg -1 , the biomass of common Chinese cabbage cultivated for 30 d increased by 46.4% compared to the control compost of rice straw. These results indicated that the composite inoculants have great application potential in straw composts.

Alzheimer's disease (AD) is the most common cause of cognitive impairment in older people. With the aging of society is more and more serious, AD caused great burden to patients and society. A β is a classical biomarker of AD, which has been widely used in clinical diagnosis of AD patients. Compared with positron emission tomography (PET) and single photon emission computed tomography (SPECT), near infrared fluorescence imaging has many advantages including highly sensitive, non-invasive, safety and inexpensive. Therefore, many research groups have focused on developing the molecular probes of near-infrared fluorescence (NIRF) imaging. In this article, we will review the progress of the probes of NIRF.

Objective. The aim of this study was to compare the differences in thyroid hormone, intelligence, attention, and quality of life (QoL) of children with obstructive sleep apnea hypopnea syndrome (OSAHS) before and after endoscopic adenoidectomy. Method. A total of 35 OSAHS children (21 males and 14 females with a mean age of 6.81 ± 1.08 years) were included in this study for analyzing the levels of thyroid hormone, intelligence, attention, and QoL. There were 22 children underwent endoscopic adenoidectomy with bilateral tonsillectomy (BT), while the other 13 children who underwent endoscopic adenoidectomy without bilateral tonsillectomy without BT. Results. Our results revealed no significant difference in serum free triiodothyronine (FT3), free thyroxine (FT4), and thyroid stimulating hormone (TSH) levels in OSAHS children before and after endoscopic adenoidectomy (all P > 0.05). However, there were significant differences in full-scale intelligence quotient (FIQ) (92.45 ± 5.88 versus 106.23 ± 7.39, P < 0.001), verbal intelligence quotient (VIQ) (94.17 ± 15.01 versus 103.91 ± 9.74, P = 0.006), and performance intelligence quotient (PIQ) (94.12 ± 11.04 versus 104.31 ± 10.05, P = 0.001), attention (98.48 ± 8.74 versus 106.87 ± 8.58, P < 0.001), and total OSA-18 scores (87.62 ± 17.15 versus 46.61 ± 10.15, P < 0.001) between before and after endoscopic adenoidectomy in OSAHS children. Conclusion. Our findings provided evidence that the intelligence, attention, and QoL of OSAHS children may be significantly improved after endoscopic adenoidectomy.

Background: To investigate the effect of celecoxib on telomerase activity and apoptosis in a human laryngeal squamous carcinoma cell line (Hep-2 cells)., Materials and Methods: The growth inhibition rate of Hep-2 cells in vitro was measured by MTT assay, and apoptosis by TUNEL assay and flow cytometry (FCM). The TRAP-ELISA method was used to determine telomerase activity in Hep-2 cells. The mRNA expression of human telomerase RNA component(hTR), human telomerase reverse transcriptase (hTERT) and human telomerase-associated protein(hTEP1) was determined by RT-PCR assay. Expression of Bax and Bcl-2 proteins was assessed by Western blotting., Results: Celecoxib can inhibit proliferation and induce apoptosis in a dose- and time-dependent manner, repress telomerase activity, decrease hTERT mRNA and Bcl-2 protein expression and increase Bax protein expression, PGE2 had no effect on telomerase., Conclusions: Celecoxib had the antiproliferative and pro-apoptotic effect in Hep-2 cells. Apoptosis was accompanied by a decrease in telomerase activity which was directly correlated with hTERT mRNA and up-regulation of Bax/Bcl-2. Bcl-2 may thus play an important role in telomerase activity as well as apoptosis.

Basal-type keratinocytes, isolated from newborn rat skin and separated on Percoll density gradients, proliferate in low (0.1 mM) calcium medium and, after raising the calcium level to normal (1.96 mM), stratify. Cells in the low calcium culture do not have extensive cell-cell connections, as seen with fluorescein isothiocyanate (FITC)-conjugated insulin. Fluorescein isothiocyanate-conjugated concanavalin A and Griffonia simplicifolia isolectin B4, but not peanut agglutinin (PNA), fluorescently label these cells. In 3-day-old low calcium cultures, within 2 h after raising the calcium of the medium to the normal level, intense binding of PNA to cells appears and neighboring cells are connected through bundles of filaments that are fluorescently labeled by FITC-insulin. After 2 days in normal calcium medium, the cultures exhibit relatively smooth, straightlined, cell boundaries that are labeled by FITC-insulin and cell boundaries and intracellular granules that are stained by hematoxylin. One day later, similar cell boundaries are present, but they are not significantly decorated by FITC-insulin and, under phase contrast microscopy, are dark. Free FITC gives labeling patterns similar to those given by FITC-insulin, but the FITC labeling is blocked by mercaptoethanol and dithiothreitol in contrast to FITC-insulin binding. The present results suggest the insulin moiety is involved in the labeling by FITC-insulin and the labeling is chronologically related to the stage of cell differentiation.