Intermittent sliding-lock-knot suture for limbal conjunctival autograft fixation in pterygium surgery: a technique note.

AIM: To report a technique used with intermittent sliding-lock-knot (ISLK) fixation for limbal conjunctival autografts in pterygium surgery and compared with those of routine intermittent (RI) fixation. METHODS: Consecutive patients with primary pterygium who had undergone pterygium excision combined with limbal conjunctival autograft transplantation between March 2021 and March 2022 at our institute were retrospectively analyzed. Primary outcome measures were mean duration of surgery and suture removal, degree of conjunctival hyperemia on postoperative day 1, pain score at suture removal, postoperative symptoms at 6mo, including conjunctival hyperemia, foreign body sensation, and graft stability. RESULTS: Ninety-eight patients underwent monocular surgery and were divided into ISLK (51 eyes) and RI (47 eyes) groups according to the type of conjunctiva autograft fixation method planned. There was no significant difference in mean duration of surgery between the two groups (18.59±2.39min vs 18.15±2.20min, P=0.417); however, compared to the RI group, shorter suture removal times were observed in the ISLK group [0.58min (0.42-0.87) vs 3.00min (2.21-4.15), P<0.001]. The degree of conjunctival hyperemia on postoperative day 1 was milder in the ISLK group (P<0.001). Pain scores at suture removal were lower in the ISLK group than in RI group [1 (0-3) vs 2 (1-4), P<0.001]. Postoperative symptoms at 6mo were comparable between the groups (P=0.487), with no recurrence. CONCLUSION: ISLK is an innovative method for limbal conjunctival autograft fixation after pterygium excision. Compared to RI fixation, ISLK facilitates suture removal and reduces discomfort, with comparable surgery duration and less conjunctival hyperemia.

High sensitivity atomic fluorescence spectroscopy for the detection of AsIII by selective electrolysis of arsenic on nanoflowers-like Fe/NFE.

Modified electrosynthetic sample introduction technique is a reliable means of solving the problem of high sensitivity analysis of trace arsenite. This article attempts to achieve selective electroreduction of AsIII through the construction of electrode surfaces with different structures and materials from the perspective of interface reactions. Among the four transition metal modifiers, the iron modified nickel foam electrode with nano-flower structure documented higher efficiency in inducing arsenic reduction and better species selectivity. Systematic electrochemical and spectroscopic tests suggest that strong adsorption effect between Fe and AsIII, appropriate hydrogen evolution potential, and catalytic activity jointly promote efficient electroreduction of AsIII. Optimization based on electrode materials and electrolysis conditions, with high sensitivity, wide linear range (0.1-50 µg L-1), and excellent species selectivity, this paper offers an efficient and economic sample introduction method for trace AsIII/V selective atomic spectroscopy direct determination.

Should ocular Demodex be checked and treated in refractory keratitis patients without blepharitis?

AIM: To evaluate the correlation between Demodex infestation and keratitis, and to assess demodicosis using a simple approach. METHODS: A modified slit lamp illumination (at 40× magnification) was used to observe Demodex tails in 40 patients with refractory keratitis and 80 healthy controls. Bacterial smear and culture of the conjunctival sac and corneal lesion were performed to identify the pathogen. Tea tree oil ointment (TTOO) was added as a Demodex killing agent for lid scrubs to the treatment when Demodex infestation was confirmed. RESULTS: Demodex tails were found in all patients compared to 42/80 of the controls (P<0.01). Seventeen patients presented blepharitis, while 23 were free of scales and inflammation at the lid margin. The demodicosis was mild, moderate, and severe in 8, 19, and 13 patients, respectively, compared to mild in 42 controls (P<0.01). The keratitis was mild, moderate, and severe in 13, 19, and 8 patients, respectively. The severity of Demodex infestation was not correlated to the severity of keratitis (P=0.126). The growth of Staphylococcus was revealed in nine patients who did not react to antibiotic eye drops prior to the TTOO treatment. Patients' signs and symptoms got resolved after the lid scrub with TTOO. CONCLUSION: Ocular Demodex needs to be checked and treated in refractory keratitis patients with or without blepharitis. A slit-lamp illumination under high magnification favors the judgment of the severity of Demodex infestation.

Quantitative anti-HBc combined with quantitative HBsAg can predict HBsAg clearance in sequential combination therapy with PEG-IFN-α in NA-suppressed chronic hepatitis B patients.

Background and aims: Precise predictors are lacking for hepatitis B surface antigen (HBsAg) clearance under the combination therapy of nucleos(t)ide analogs (NA) and pegylated interferon-alpha (PEG-IFN-α) in patients with chronic hepatitis B (CHB). This study aimed to determine the quantitative anti-hepatitis B core antibody (qAnti-HBc) and quantitative hepatitis B core-related antigen (qHBcrAg) as predictors for HBsAg clearance in NA-suppressed patients with CHB receiving PEG-IFN-α add-on therapy. Methods: Seventy-four CHB patients who achieved HBV DNA suppression (HBV DNA < 20 IU/ml) and quantitative HBsAg (qHBsAg) < 1,500 IU/ml after ≥1 year of NA treatment were enrolled. Fifteen patients continued on NA monotherapy, while 59 patients received PEG-IFN-α add-on therapy. Serum qAnti-HBc and qHBcrAg levels were detected every 12 or 24 weeks for add-on and NA-alone groups, respectively. Results: Serum qAnti-HBc but not qHBcrAg levels at baseline were negatively correlated with the duration of prior NA therapy. After 48-week treatment, both qAnti-HBc and qHBcrAg levels declined further, and 17/59 (28.81%) and 0/15 (0%) achieved HBsAg clearance in add-on and NA groups, respectively. In the add-on group, the rate of HBsAg clearance was significantly higher in patients with baseline qAnti-HBc < 0.1 IU/ml (52.63%). Logistic regression analysis identified baseline qAnti-HBc but not qHBcrAg, which was an independent predictor for HBsAg loss. Receiver operating characteristic curve analysis showed that the combination of qAnti-HBc and qHBsAg had a better predictive value for HBsAg clearance. Conclusions: A combination of qHBsAg and baseline qAnti-HBc levels may be a better prediction strategy for HBsAg clearance in NA-suppressed CHB patients receiving PEG-IFN-α add-on therapy.

Zinc enhances liquid-liquid phase separation of Tau protein and aggravates mitochondrial damages in cells.

Intraneuronal neurofibrillary tangles composed of Tau aggregates have been widely accepted as an important pathological hallmark of Alzheimer's disease. Liquid-liquid phase separation (LLPS) of Tau can lead to its aggregation, and Tau aggregation can then be enhanced by zinc. However, it is unclear whether zinc modulates the formation of Tau stress granules in cells. We herein report that zinc promotes the formation of stress granules containing a pathological mutant ΔK280 of full-length human Tau. Furthermore, zinc promotes LLPS of ΔK280 of full-length Tau, shifting the equilibrium phase boundary to a lower protein concentration, and modulates the liquid nature of droplets formed by this pathological mutation. Zinc also promotes pathological phosphorylation of ΔK280 in neuronal cells, and aggravates mitochondrial damage and elevates reactive oxygen species production induced by Tau aggregation. Importantly, we show that treatment of cells with zinc increases the interaction between full-length Tau and G3BP1 inside stress granules to promote the formation of Tau filaments and increase Tau toxicity in neuronal cells. Collectively, these results demonstrate how Tau condensation and mitochondrial damages induced by Tau aggregation are enhanced by zinc to deteriorate the pathogenesis of Alzheimer's disease, bridging the gap between Tau LLPS and aggregation in neuronal cells.

Systemic osteoprotective effects of Epimedii Folium and Ligustri Lucidi Fructus in senile osteoporosis rats by promoting the osteoblastogenesis and osteoclastogenesis based on MLP-ANN model.

BACKGROUND: Senile osteoporosis (SOP), which is caused by unbalanced bone remodeling, leads to significant economic and societal burdens globally. The combination of Epimedii Folium (EF) and Ligustri Lucidi Fructus (LLF) serves as a commonly-used prescription for SOP in Traditional Chinese Medicine (TCM). This study aimed to evaluate the osteoprotective effects of EF and LLF in combination on SOP rats based on the constructed multilayer perception (MLP)-artificial neural network (ANN) model. METHODS: 15 month old male Sprague-Dawley rats were administrated with EF, LLF or the combination of EF and LLF (EF&LLF) for 2 months, while 17 month old rats were used as the aging control group. All the rats were anesthetized with 25% ethyl carbamate, then their serum liver and bone tissues were taken. We detected bone mass, bone mineral density (BMD), biomechanics and the microstructure of bone trabecula by micro-CT and H&E staining to evaluate the degree of osteoporosis. Blood lipids and serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and γ-glutamyl transferase (GGT) and liver pathology were use to assess the side effects of drugs. Levels of alkaline phosphatase (ALP) and Tartrate-resistant acid phosphatase (TRACP) and the ratio of ALP to TRACP both in serum and bone were measured for the evaluation of bone turnover rate. The bone mRNA and protein expression of osteoprotegerin (OPG), nuclear factor-kappa B ligand (RANKL), macrophage colony-stimulating factor (M-CSF), d2 isoform of vacuolar (H+) ATPase (ATP6V0d2), insulin-like growth factor (IGF-1), bone morphogenetic protein-2 (BMP2), M-CSF, Wnt5a, transforming growth factor-ß1 (TGF-ß1) were detected for evaluating bone metabolism. RESULTS: The results showed that EF&LLF improved bone mass and bone quality by preventing bone loss, increasing maximal load as well as protecting the micro-structural retrogressive change of trabecular bone in SOP rats; ameliorated the steatosis in the liver and decreased blood lipids and serum ALT, AST and GGT; enhanced bone remodeling by stimulating the expression of ALP and TRACP. At the molecular levels, EF&LLF stimulated the osteoclastogenesis by upregulating the protein and mRNA expression of OPG, RANKL, M-CSF and ATP6V0d2; meanwhile, EF&LLF stimulated osteoblastogenesis by enhancing the expression of TGF-ß1, BMP2, Wnt5a and IGF-1. According to our established MLP model, EF&LLF has a better effect on osteoclastogenesis or steoblastogenesis in SOP rats than EF or LLF. CONCLUSIONS: These findings demonstrate that the systemic bone protective effects of EF&LLF by promoting bone remodeling in aging rats might be a substitute medicine for the treatment of SOP.

Phase Separation and Cytotoxicity of Tau are Modulated by Protein Disulfide Isomerase and S-nitrosylation of this Molecular Chaperone.

Cells have evolved molecular chaperones that modulate phase separation and misfolding of amyloidogenic proteins to prevent neurodegenerative diseases. Protein disulfide isomerase (PDI), mainly located at the endoplasmic reticulum and also present in the cytosol, acts as both an enzyme and a molecular chaperone. PDI is observed to be S-nitrosylated in the brain of Alzheimer's disease patients, but the mechanism has remained elusive. We herein report that both wild-type PDI and its quadruple cysteine mutant only having chaperone activity, significantly inhibit pathological phosphorylation and abnormal aggregation of Tau in cells, and significantly decrease the mitochondrial damage and Tau cytotoxicity resulting from Tau aberrant aggregation, highlighting the chaperone property of PDI. More importantly, we show that wild-type PDI is selectively recruited by liquid droplets of Tau, which significantly inhibits phase separation and stress granule formation of Tau, whereas S-nitrosylation of PDI abrogates the recruitment and inhibition. These findings demonstrate how phase separation of Tau is physiologically regulated by PDI and how S-nitrosylation of PDI, a perturbation in this regulation, leads to disease.

Purification, chemical characterization and antioxidant activities of polysaccharides isolated from Mycena dendrobii.

Two polysaccharides, MDP-1 and MDP-2, were obtained from the fermentation liquid of M. dendrobii by anion exchange chromatography and gel filtration. Their chemical structures were measured by FT-IR, GC, 1H and 13C NMR spectra, indicating the mainly compositions of mannose, xylose, and galactose for MDP-1; galacturonic acid, galactose and rhamnose for MDP-2. Furthermore, the antioxidant activities of MDPs were investigated, showing different antioxidant activities, in which MDP-2 performed noticeable, with excellent superoxide radical activity better than BHT, high DPPH radical activity (IC50 at 227 µg/mL) comparable with BHT, moderate reducing power activity and hydroxyl radical scavenging activity. The results indicated that the fermentation liquid of M. dendrobii could be used as a potential natural source of antioxidant.

Survivin regulates chromosome segregation by modulating the phosphorylation of Aurora B during porcine oocyte meiosis.

SURVIVIN is an essential chromosomal passenger complex (CPC) subunit and participates in cell division. In this study, we used porcine oocyte as a model to investigate the roles of Survivin during porcine oocyte maturation. Survivin was highly expressed in germinal vesicle (GV) and germinal vesicle breakdown (GVBD) stages oocytes, mainly localized in the GV at GV stage and on the chromosomes after GVBD. We have used RNA interference to specifically deplete Survivin in oocytes during in vitro maturation (IVM). Immunofluorescence assay showed that Survivin-depleted oocytes failed to produce polar body in meiosisⅠ (failed to complete cytokinesis), and they were arrested in metaphaseⅠwith misaligned chromosomes. The homologous chromosomes in Survivin-depleted oocytes could not be separated normally. Moreover, both the phosphorylation levels of Aurora B and the mRNA level of Mad2L1 related to spindle assembly checkpoint (SAC) was decreased in Survivin-depleted oocytes, which thus inhibited the degradation of Cyclin B1 (CCNB1) to complete meiosis. Taken together, we conclude that Survivin is an important mediator of centromere and midbody docking of Aurora-B as well as its activity and regulates SAC and MPF activity during meiosis in porcine oocytes.

Progress in Experimental and Clinical Research of the Diabetic Retinopathy Treatment Using Traditional Chinese Medicine.

Diabetic retinopathy (DR), one of the most common microvascular complications of diabetic mellitus, is currently the main cause of adult-acquired blindness. The pathogenesis of DR is complex and the current clinical application of various treatment methods cannot completely prevent the development of this disease. Many reports have been published regarding the treatment of DR with Traditional Chinese Medicine (TCM), which has received increasing attention from medical practitioners worldwide. Studies published between 1994 and April 2017 were collected from the CNKI, VIP, Medline and Web of Science databases, as well as from Chinese traditional books and Chinese Pharmacopoeia, subsequently obtaining more than 550 studies. Thereafter, the status quo of DR treatment using TCM had been summarized according to four aspects - compound formula therapy, Chinese herbal medicine extracts and monomer therapy, integrated traditional Chinese and Western medicine therapy, and Chinese medicine external treatment. According to the literature reviewed herein, TCM has had definite effects on the prevention and treatment of DR, especially when used in combination with modern medical methods. However, the lack of a unified standard on the syndrome differentiation of DR and the lack of support of evidence-based medicine theory in clinical practice have been consistent concerns in previous research studies and needs to be addressed in subsequent studies.

Superficial punctate keratopathy in a pediatric patient was related to adenoid hypertrophy and obstructive sleep apnea syndrome: a case report.

BACKGROUND: Known causes of superficial punctuate keratopathy (SPK) in children include entropion, viral infection, blepharokeratoconjunctivitis (BKC), and toxicity of eye drops. However, there are some SPK patients whose causes could not be identified well. Herein, we describe the history, diagnosis, treatment, and prognosis of a rare case. CASE PRESENTATION: To report a case of superficial punctate keratopathy (SPK) which coexisted with floppy eyelid syndrome (FES) and presented as intermittent red eye and blurred vision in an 11-year-old boy who slept in the prone position. His condition did not improve despite treatment with topical antibiotics (levofloxacin, tobramycin), steroid eye drops (prednisolone), and artificial tears. The patient was diagnosed with tonsil hypertrophy and nasopharyngeal adenoid hypertrophy and obstructive sleep apnea syndrome (OSAS). He underwent tonsillectomy and adenoidectomy. Then he started sleeping in the supine position postoperatively. The SPK, red eye and blurred vision completely resolved after surgery without additional treatment. The corneal sensation also recovered gradually during the next 7 years. However, the floppy eyelid did not resolve. CONCLUSION: Recurrent SPK of childhood might be related to tonsil hypertrophy, adenoid hypertrophy and OSAS, which can be rehabilitated by a surgical approach.

Sodium fluoride disturbs DNA methylation of NNAT and declines oocyte quality by impairing glucose transport in porcine oocytes.

Sodium fluoride (NaF) is used as a medicine to prevent tooth decay; however, excessive NaF could cause a pathological damage to the health. Recent studies showed that NaF impaired mouse oocyte maturation, included of abnormal spindle configuration, actin cap formation, cortical granule-free domain formation, and the following development after fertilization. However, few studies used large animals as models to study the toxicology of NaF on oocytes maturation. We proposed a hypothesis that NaF would affect the nuclear and cytoplasmic maturation of porcine oocytes and DNA methylation pattern of imprinted genes in oocytes. Our results showed that NaF affected cumulus expansion, polar body emission, spindle morphology, cortical granule distribution, early apoptosis, and the following development after parthenogenetic activation during porcine oocyte maturation. Moreover, NaF increased the DNA methylation of NNAT and decreased its expression, which disturbed the glucose transport in oocytes. These results suggest that NaF impairs the porcine oocytes maturation epigenetically, which provides a new toxicological mechanism of NaF on the oocyte maturation. Environ. Mol. Mutagen. 59:223-233, 2018. © 2017 Wiley Periodicals, Inc.

Function and regulation mechanism of Chk1 during meiotic maturation in porcine oocytes.

Checkpoint 1 (Chk1), as an important member of DNA replication checkpoint and DNA damage response, has an important role during the G2/M stage of mitosis. In this study, we used porcine oocyte as a model to investigate the function of Chk1 during porcine oocyte maturation. Chk1 was expressed from germinal vesicle (GV) to metaphase II (MII) stages, mainly localized in the cytoplasm at GV stage and moved to the spindle after germinal vesicle breakdown (GVBD). Chk1 depletion not only induced oocytes to be arrested at MI stage with abnormal chromosomes arrangement, but also inhibited the degradation of Cyclin B1 and decreased the expression of Mitotic Arrest Deficient 2-Like 1 (Mad2L1), one of spindle assembly checkpoint (SAC) proteins, and cadherin 1 (Cdh1), one of coactivation for anaphase-promoting complex/cyclosome (APC/C). Moreover, Chk1 overexpression delayed GVBD. These results demonstrated that Chk1 facilitated the timely degradation of Cyclin B1 at anaphase I (AI) and maintained the expression of Mad2L1 and Cdh1, which ensured that all chromosomes were accurately located in a line, and then oocytes passed metaphase I (MI) and AI and exited from the first meiotic division successfully. In addition, we proved that Chk1 had not function on GVBD of porcine oocytes, which suggested that maturation of porcine oocytes did not need the DNA damage checkpoint, which was different from the mouse oocyte maturation.

Melatonin prevents postovulatory oocyte aging and promotes subsequent embryonic development in the pig.

Oxidative stress is known as a major contributing factor involved in oocyte aging, which negatively affects oocyte quality and development after fertilization. Melatonin is an effective free radical scavenger and its metabolites AFMK and AMK are powerful detoxifiers that eliminate free radicals. In this study, we used porcine oocytes to test the hypothesis that melatonin could scavenge free radicals produced during oocyte aging, thereby maintaining oocyte quality. We compared reactive oxygen species levels, apoptosis levels, mitochondrial membrane potential ratios, total glutathione contents and expression levels in fresh, aged and melatonin-treated aged porcine oocytes and observed the percentage of blastocyst formation following parthenogenetic activation. We found that melatonin could effectively maintain the morphology of oocytes observed in control oocytes, alleviate oxidative stress, markedly decrease early apoptosis levels, retard the decline of mitochondrial membrane potential and significantly promote subsequent embryonic development in oocytes aged for 24 hr in vitro. These results strongly suggest that melatonin can prevent postovulatory oocyte aging and promote subsequent embryonic development in the pig, which might find practical applications to control oocyte aging in other mammalian species including humans to maintain the quality of human oocytes when performing clinical assisted reproductive technology.

Caffeine delays oocyte aging and maintains the quality of aged oocytes safely in mouse.

Caffeine, as an oocyte aging inhibitor, was used in many different species to control or delay oocyte aging. However, the safety of caffeine and developmental competence of aged oocytes inhibited by caffeine has not been studied systematically. So we detected the spindle morphology, distribution of cortical granules, zona pellucida hardening and pronucleus formation to assess oocyte quality of caffeine treated oocytes. We found that aged oocytes treated by caffeine maintained weak susceptibility to activating stimuli and regained normal competent after aged further 6 hr. Caffeine maintained the spindle morphology, changed cortical granules distribution of aged oocytes and could not prevent zona pellucida hardening. Furthermore, caffeine increased pronucleus formation of aged oocytes and decreased fragmentation after fertilization. These results suggested that caffeine could maintain the quality of aged oocytes safely in mouse.

Oocyte aging-induced Neuronatin (NNAT) hypermethylation affects oocyte quality by impairing glucose transport in porcine.

DNA methylation plays important roles in regulating many physiological behaviors; however, few studies were focused on the changes of DNA methylation during oocyte aging. Early studies showed that some imprinted genes' DNA methylation had been changed in aged mouse oocytes. In this study, we used porcine oocytes to test the hypothesis that oocyte aging would alter DNA methylation pattern of genes and disturb their expression in age oocytes, which affected the developmental potential of oocytes. We compared several different types of genes and found that the expression and DNA methylation of Neuronatin (NNAT) were disturbed in aged oocytes significantly. Additional experiments demonstrated that glucose transport was impaired in aged oocytes and injection of NNAT antibody into fresh oocytes led to the same effects on glucose transport. These results suggest that the expression of NNAT was declined by elevating DNA methylation, which affected oocyte quality by decreasing the ability of glucose transport in aged oocytes.

Terpinen-4-ol is the Most Active Ingredient of Tea Tree Oil to Kill Demodex Mites.

PURPOSE: To determine the active ingredient in tea tree oil (TTO) responsible for its reported killing effect on Demodex mites, the most common ectoparasite found in the human skin extending to the eye. METHODS: Using a reported in vitro killing assay to measure the survival time of adult Demodex folliculorum up to 150 minutes, we have screened serial concentrations of 13 of the 15 known ingredients of TTO (ISO4730:2004) that were soluble in mineral oil and examined their synergistic relationships in killing mites. The most potent ingredient was then tested for its efficacy in killing Demodex in vivo. RESULTS: All ingredients exhibited a dose-dependent killing effect. Besides Terpinen-4-ol, the order of relative potency did not correlate with the order of relative abundance in TTO for the remaining 12 ingredients. Terpinen-4-ol was the most potent ingredient followed by α-Terpineol, 1,8-Cineole and Sabinene. Terpinen-4-ol, the most abundant ingredient in TTO, was more potent than TTO at equivalent concentrations and its killing effect was even observable at a mere concentration of 1%. Terpinen-4-ol exhibited a significant synergistic effect with Terpinolene, but an antagonistic effect with α-Terpineol in killing mites (both P < 0.05). In vivo, Terpinen-4-ol was shown to eradicate mites. CONCLUSIONS: The above finding suggests that deployment of Terpinen-4-ol alone should enhance its potency in killing Demodex mites by reducing the adverse and antagonistic effects from other ingredients in TTO. TRANSLATIONAL RELEVANCE: Terpinen-4-ol can be adopted in future formulations of acaricides to treat a number of ocular and cutaneous diseases caused by demodicosis.

[NVP-BEZ235 inhibits proliferation and colony-forming capability of CD34(+)CD38(-) human acute myeloid leukemia stem cells].

This study was aimed to explore the effect of NVP-BEZ235, a dual phosphatidylinositol 3-kinase/mammalian target of rapamycin inhibitor, on proliferation, cell cycle and colony forming capability of CD34(+)CD38(-) human acute myeloid leukemia (AML) KG1a cells. Flow cytometry was used to detect expression of CD34 and CD38 on the surface of human AML KG1a cells; Trypan blue assay was used to analyze the effect of NVP-BEZ235 at various concentrations on proliferation of KG1a cells; flow cytometry was performed to examine the cell cycle of KG1a cells after NVP-BEZ235 treatment; Soft agar colony-forming experiment was used to detect the colony forming ability of KG1a cells treated with NVP-BEZ235 at various concentrations. The results indicated that the percentage of CD34(+)CD38(-) AML KG1a cells was (98.02 ± 0.72)%. NVP-BEZ235 (0.125 - 1 µmol/L) inhibited the proliferation of KG1a cells in a time-and dose-dependent manner (P < 0.05) and the 50% inhibition concentrations (IC50) at 24 h and 48 h were 0.597 µmol/L and 0.102 µmol/L, respectively. KG1a cells were arrested at G0/G1 phase after treating with 0.5 µmol/L NVP-BEZ235 for 24 h, it was significantly higher than that of control group (83.2 ± 3.80)% vs (43.47 ± 9.60)% (P < 0.05). KG1a cells treated with NVP-BEZ235 (0 - 1 µmol/L) for 14 d and 21 d, the number of colony decreased respectively from (375.67 ± 21.46) per 2500 KG1a cells and (706.33 ± 87.31) per 2500 KG1a cells to 0, with statistical significance (P < 0.05). It is concluded that NVP-BEZ235 can inhibit proliferation and colony-forming capability of CD34(+)CD38(-) human AML KG1a cells.

Ginsenoside Rg1 protects human fibroblasts against psoralen- and UVA-induced premature senescence through a telomeric mechanism.

This study was aimed to investigate the protective effects of ginsenoside Rg1 on 8-methoxypsoralen(8-MOP)/Ultraviolet A (UVA)-induced premature senescence in human fibroblasts, and the underlying mechanism. We established a stress-induced premature senescence model by 8-MOP/UVA irradiation. The aging condition was determined by histochemical staining of senescence-associated ß-galactosidase (SA-ß-gal). Relative telomere length was calculated by the ratio of the amount of telomere DNA versus single copy DNA by real-time polymerase chain reaction, and protein levels of p-P53, p21(WAF-1) and p16(INK-4a) were estimated by Western blotting. Compared with the 8-MOP/UVA treatment group, we found that the irradiated fibroblasts pretreated with ginsenoside Rg1 demonstrated a decrease in the expression of SA-ß-gal, a downregulation in the level of senescence-associated proteins, and a deceleration in telomere shortening. Taken together, these results suggest that ginsenoside Rg1 significantly antagonizes premature senescence induced by 8-MOP/UVA in fibroblasts.

Effect of total body X-ray irradiation on lymph node in Tibet minipig.

The purpose of this study was to determine the time-dose-effect of total body X-ray irradiation on lymphocytes in lymph nodes and peripheral blood in Tibet minipigs. Forty-eight Tibet minipigs were assigned into 6 groups including 5 experimental groups with 9 and the control group with 3. The minipigs in experimental groups were subjected to a total body X-ray irradiation of 2, 5, 8, 11, and 14 Gy respectively. Lymph nodes and peripheral blood samples were collected at 6, 24, and 72 hours after X-ray exposure and received histological microscopy examination and apoptosis analysis. Histology observation showed that the number of lymphocytes decreased within the lymph nodes with the increase of radiation doses and exposure time. The observation of transmission electron microscopy (TEM) showed typical apoptotic cells below 11 Gy while at 14 Gy necrotic cells were dominant. The apoptotic rate of lymphocytes in the lymph nodes was positively correlated with radiation dose in the range of 2-11 Gy, and reached the maximal level (39.4 ± 2.8) at 24 hours after 11 Gy irradiation, followed by a decrease in the apoptotic rate, but still higher than that of the control group. The number of lymphocytes in the peripheral blood samples was decreased significantly by increasing of the radiation dose and exposure time. We conclude that early damage of lymphocytes by total body X-ray irradiation is dose and time dependent below 11 Gy and before 24 hours post irradiation, and that the dosage of irradiation less than 11 Gy induced apoptosis, whereas the dose at 14 Gy resulted in necrosis in lymphocytes of the lymph nodes.