Induction of G1 cell cycle arrest and cyclin D1 down-regulation in response to pericarp extract of Baneh in human breast cancer T47D cells

Background and the purpose of the study

Natural products from plants have an important role in the development and production of new drugs mainly for cancer therapy. More recently, we have shown that the pericarp methanolic extract of Pistacia atlantica sub kurdica (with local name of Baneh) as a rich source of active biological components with high antioxidant and radical scavenging activities, has ability to cease proliferation and induce apoptosis in T47D human breast cancer cells. The present study aimed to clarify whether Baneh extract able to alter cell cycle progression of T47D cells or not.

Methods

In order to study the possible effect of Baneh extract on cell cycle of T47D cells, we evaluated cell cycle distribution and its regulatory proteins by flow cytometry and western blot analysis respectively.

Results

Baneh extract induced G₀/G₁ cell cycle arrest in conjunction with a marked decrease in expression of cyclin D1 and cdk4 that was strongly dependent on time of exposure. In parallel, Dox-treated T47D cells in early time points were accumulated on S phase, but after 48 h cell cycle progression was inhibited on G₂/M. Dox promoted striking accumulation of cyclin B1 rapidly and enhanced cyclin A abundance.

Conclusion

Taken together, our results establish that the antitumor activity of the pericarp extract of Baneh partly is mediated via cell cycle arrest and downregulation of cyclin D1 and cdk4 expression. These findings warrant further evaluation regarding the mechanism(s) of action of this promising anticancer agent.     

Induction of apoptosis and cell cycle arrest by pericarp polyphenol-rich extract of Baneh in human colon carcinoma HT29 cells

Plants as important source of natural active components with anticancer effects commonly are different in structure and biological properties. The pericarp of Pistacia atlantica sub kurdica with local name of Baneh, a rich source of active phytochemicals, contains noticeable amounts of polyphenolic compounds, flavonoids and anthocyanins. Therefore, the antiproliferative, apoptosis induction and cell cycle alterations of Baneh were evaluated in human colon carcinoma HT29 cells. The Baneh extract (0.7 mg/ml) resulted in 50% growth inhibition similar to 500 nM of Doxorubicin (Dox) in HT29 cells after 72 h. The down-regulation of cyclin A protein by Baneh extract induced S phase delay in cell cycle progression of HT29 cells. Unlike the Baneh extract, Dox showed G2/M accumulation of HT29 cells which was associated with an increase in cyclin A and cyclin B1 protein expression. Furthermore, the induction of apoptosis following Baneh extract and Dox treatment in HT29 cells was confirmed by DNA fragmentation and translocation of phosphatidylserine. The morphological characteristics of apoptosis were also observed in HT29 cells exposed to the Baneh extract and Dox. These results suggest that due to the existence of bioactive components, methanolic extract of the Baneh has significant cytotoxic effects against human colon carcinoma HT29 cells.     

The Ross operation: clinical results and echocardiographic findings

Between November 2001 and September 2004, 80 patients aged 11 to 56 years (mean, 27.6 years) underwent the Ross operation. The mean preoperative New York Heart Association functional class was 2.37 +/- 0.72, and the mean ejection fraction was 52.8% +/- 16%. Aortic involvement included stenosis in 19 (24%) patients, regurgitation in 22 (28%), and both in 39 (49%). Root replacement was the technique used in all cases. The mean hospital stay was 5 days, and 74 patients (93%) were followed up for 4-48 months. Four-year actuarial survival rate was 96.25%. Postoperative echocardiography revealed no pulmonary autograft insufficiency in 50 patients (63%), trivial to mild insufficiency in 22 (28%), moderate insufficiency in 2 (3%), and severe insufficiency in one (1%). Two patients required autograft re-intervention. Postoperative echocardiography of the pulmonary homograft valve showed severe stenosis (peak gradient > 50 mm Hg) in 2 patients, and moderate stenosis (peak gradient 25-50 mm Hg) in one. The mean postoperative left ventricular ejection fraction was 51.4%. The Ross operation can be considered an elegant alternative to prosthetic valves in the treatment of aortic valve diseases in developing countries.     

Partial cholecystectomy as a safe and viable option in the emergency treatment of complex acute cholecystitis: a case series and review of the literature

Partial cholecystectomy (PC) is an alternative choice to standard cholecystectomy in situations with increased risk of Calot's components injury. We reported our experience with the patients treated with PC and reviewed the literature. Fifty-four patients with complex acute cholecystitis underwent PC, including conventional partial cholecystectomy (CPC; n = 48) and laparoscopic partial cholecystectomy (LPC; n = 6). The clinical diagnosis was verified by ultrasonography. In addition, we reviewed 1190 published cases (1972-2005) who underwent a "nonconventional" surgery for severe cholecystitis, including cholecystostomy, CPC, or LPC. Review of the literature, including our cases, showed a male:female ratio of 1.3:1. The major operative indication was severe acute cholecystitis. Procedures included cholecystostomy (65.8%) and PC (34.2%). In the follow-up (n = 1190), biliary leak (4.8%), retained stones (4.6%), recurrent symptoms (2.3%), wound infections (1.9%), persistent biliary fistula (0.9%), and prolonged biliary drainage (0.2%) were found, with an overall mortality rate of 9.4 per cent. In 133 patients, because of postoperative complications (e.g., recurrent symptoms, remaining common bile duct stones, or persistence of bile fistula), reoperation was necessary, including 121 cases (90.1%) of cholecystectomy, whereas the other 11 patients underwent other procedures such as common bile duct exploration or closure of the fistula. The surgical trend for complex acute cholecystitis treatment has been changed from only cholecystostomy to a spectrum of cholecystostomy, CPC, and LPC with the progressive increase of PC. The proportion of the LPC compared with CPC has also increased during recent years. It seems that PC is a safe procedure for treating complicated acute cholecystitis. Whether the indication and need for alternative techniques to standard cholecystectomy is changing should be evaluated in future studies.     

Immunolocalization of phospho-Arg-directed protein kinase-substrate in hypoxic kidneys using in vivo cryotechnique

Protein kinases (PKs) phosphorylate proteins at active regions for signal transduction. In this study, normal and hypoxic mouse kidneys were prepared using an “in vivo cryotechnique” (IVCT) and examined immunohistochemically with specific antibodies against phospho-(Ser/Thr) PKA/C substrate (P-PK-S) and phospho-(Ser/Thr) Akt substrate (P-Akt-S) to capture their time-dependent regulation in vivo. Left kidneys were cryofixed with IVCT under normal blood circulation and after varying hypoxic intervals, followed by freeze-substitution with acetone containing paraformaldehyde. Deparaffinized sections were immunostained for P-PK-S, Na⁺/HCO₃ ⁻ cotransporter NBC1, and a membrane skeletal protein, 4.1B. The P-PK-S was diffusely immunolocalized in the cytoplasm of the proximal tubules in normal kidneys, whereas NBC1 and 4.1B were detected at the basal striations of S1 and S2 segments of the proximal tubule. After 10 or 30 s hypoxia, P-PK-S was still immunolocalized in the cytoplasm of kidneys, but it was detected at the basal striations after 1 or 2 min hypoxia. The immunolocalization of P-Akt-S was the same as P-PK-S in the normal and hypoxic kidneys. Immunoblotting analyses of the kidney tissues under normal or hypoxic condition clearly identified the same 40-kDa bands. The IVCT is useful for time-dependent analysis of the immunodistribution of P-PK-S and P-Akt-S.     

Dual effects of 3, 4-methylenedioxymethamphetamine （ecstasy） on survival and apoptosis of primary hippocampal neurons

BACKGROUND： 3, 4-methylenedioxymethamphetamine （MDMA, also known as ＂ecstasy＂） has been shown to exhibit neurotoxic effects on the hippocampus. However, exposure to sub-lethal insults of MDMA has been reported to result in neuroprotection. OBJECTIVE： To investigate the effects of MDMA on hippocampal neuronal viability, caspase-3 activity, and mRNA expression of the N-methyI-D-aspartate （NMDA） receptor 2B （NR2B） subunit. DESIGN, TIME AND SETTING： A cytological, in vitro experiment was performed at the Department of Anatomy, School of Medicine, and Department of Toxicology-Pharmacology, Faculty of Pharmacy Tehran University of Medical Sciences in 2008. MATERIALS： MDMA was extracted from ecstasy tablets, which were kindly supplied by the Pharmacology-Toxicology Department, Faculty of Pharmacy, Tehran University of Medical Sciences, Iran. METHODS： Hippocampal neurons were isolated from Wistar rats at gestational day 18. Following primary culture, hippocampal neuronal viability was detected by MTT assay. Varying concentrations of MDMA （100-5 000 μmol/L） were used to determine lethal concentration 50 （LC50）, which was around 1 500 μmol/L. Five concentrations of MDMA below 1 500 μmol/L （100, 200, 400, 800, and 1 050 μmol/L） were used for the remaining experiments. After 24 hours of MDMA treatment, NR2B mRNA expression was detected by RT-PCR, and caspase-3 relative activity was determined by colorimetric assay. MAIN OUTCOME MEASURES： Hippocampal neuronal viability, caspase-3 activity, and NR2B mRNA expression. RESULTS： MDMA-induced neurotoxicity in hippocampal neuronal cultures was dose-dependent. In high concentrations （1 000-5 000μmol/L） of MDMA, neuronal viability was decreased. However, with a 500 μmol/L dose of MDMA, neuronal viability was significantly increased （P 〈 0.01）. Low concentrations of MDMA （200 and 400μmol/L） significantly decreased caspase-3 activity （P 〈 0.01）, whereas high concentrations of MDMA significantly increased caspase-3 activity （P 〈 0.01）. NR2B subunit mRNA expression was not significantly altered after 100 -1 050 μmol/L MDMA exposure. CONCLUSION： MDMA exhibits dual effects on hippocampal neuronal viability and caspase-3 activity. These effects are independent from NR2B subunit expression levels.     

Segmentation of teeth in CT volumetric dataset by panoramic projection and variational level set

Purpose

Quantification of teeth is of clinical importance for various computer assisted procedures such as dental implant, orthodontic planning, face, jaw and cosmetic surgeries. In this regard, segmentation is a major step.

Methods

In this paper, we propose a method for segmentation of teeth in volumetric computed tomography (CT) data using panoramic re-sampling of the dataset in the coronal view and variational level set. The proposed method consists of five steps as follows: first, we extract a mask in a CT images using Otsu thresholding. Second, the teeth are segmented from other bony tissues by utilizing anatomical knowledge of teeth in the jaws. Third, the proposed method is followed by estimating the arc of the upper and lower jaws and panoramic re-sampling of the dataset. Separation of upper and lower jaws and initial segmentation of teeth are performed by employing the horizontal and vertical projections of the panoramic dataset, respectively. Based the above mentioned procedures an initial mask for each tooth is obtained. Finally, we utilize the initial mask of teeth and apply a Variational level set to refine initial teeth boundaries to final contours.

Results

The proposed algorithm was evaluated in the presence of 30 multi-slice CT datasets including 3,600 images. Experimental results reveal the effectiveness of the proposed method.

Conclusion

In the proposed algorithm, the variational level set technique was utilized to trace the contour of the teeth. In view of the fact that, this technique is based on the characteristic of the overall region of the teeth image, it is possible to extract a very smooth and accurate tooth contour using this technique. In the presence of the available datasets, the proposed technique was successful in teeth segmentation compared to previous techniques.     

Sex and smoking differences in the association between gastroesophageal reflux and risk of esophageal squamous cell carcinoma in a high-incidence area: Golestan Cohort Study

Prior studies have conflicting findings regarding the association between gastroesophageal reflux disease (GERD) and esophageal squamous cell carcinoma (ESCC). We examined this relationship in a prospective cohort in a region of high ESCC incidence. Baseline exposure data were collected from 50 045 individuals using in-person interviews at the time of cohort entry. Participants were followed until they developed cancer, died, or were lost to follow up. Participants with GERD symptoms were categorized into any GERD (heartburn or regurgitation), mixed symptoms, or heartburn alone. Multivariable Cox regression was used to assess the relationship between GERD symptom group and histologically confirmed ESCC. The model was adjusted for known risk factors for GERD and ESCC. 49 559 individuals were included in this study, of which 9005 had GERD symptoms. Over 13.0 years of median follow up, 290 individuals were diagnosed with ESCC. We found no association between any GERD and risk of ESCC (aHR 0.90, 95% CI: 0.66-1.24, P = .54). Similar findings were observed for the GERD symptom subtypes. Significant interactions between any GERD and sex (P = .013) as well as tobacco smoking (P = .028) were observed. In post-hoc analyses, GERD was associated with a decreased risk of ESCC in men (aHR 0.51, 95% CI: 0.27-0.98 P = .04) and in smokers (aHR 0.26, 95% CI: 0.08-0.83 P = .02). While there was little evidence for an overall association between GERD symptoms and ESCC risk, significant interactions with sex and smoking were observed. Men and smokers with GERD symptoms had a lower risk of ESCC development.     

Delivery of Exogenous miR-124 to Glioblastoma Multiform Cells by Wharton’s Jelly Mesenchymal Stem Cells Decreases Cell Proliferation and Migration,and Confers Chemosensitivity

MicroRNAs (miRs) are potential therapeutic targets in glioblastoma multiforme (GBM), but the difficulties associated with their delivery to tumor target cells have hampered their widespread use. Mesenchymal stem cells (MSCs) can migrate to the sites of cancers, including GBM and exert anti-tumor effects. In this study, it is shown that Wharton’s jelly-MSCs (WJ-MSCs) have the ability to deliver exogenous miRs to GBM cells and the functional impact of this delivery is characterized. It is found that the labeled miR-124, as an example for miR of interest, can be successfully delivered with WJ-MSCs to U87 GBM cells via dependent or exosome-independent processes. It is demonstrated that the delivered exogenous miR-124 significantly decreases the luciferase activity of the target gene CDK6. In addition, the delivered miR-124 enhances the chemosensitivity of GBM cells to temozolomide and decreases the migration of GBM cells. These results suggest that the use of exogenous miRNA delivery with the derived exosomes from WJ-MSCs may provide a novel approach for miRNA replacement therapy in GBM cancers.     

Association of Lysyl oxidase (LOX) Polymorphisms with the Risk of Keratoconus in an Iranian Population

Background: Keratoconus is a connective tissue-related eye disease with unknown etiology that causes the loss of visual acuity. Lysyl oxidase (LOX) is an amine oxidase that catalyzes the covalent cross-link of collagens and elastin in the extracellular environment, thus determining the mechanical properties of connective tissue. The current study aimed to investigate the possible associations between two LOX polymorphisms, rs1800449 and rs2288393, and susceptibility to keratoconus.

Methods: A total of 262 Iranian subjects including 112 patients with keratoconus and 150 healthy individuals as controls were recruited. Genotyping for the LOX variants was performed using allele-specific PCR.

Results: A significant difference was found between two groups regarding allelic and genotyping distribution of LOX polymorphism at position rs1800449 G>A. The frequency of AA and GA?+?AA genotypes were increased in patients compared to controls (17% versus 8% and 62.5% versus 50%, respectively), showing a statistically significant difference (OR?=?2.827, 95% CI: 1.251–6.391, p?=?0.012). The A allele was associated with an increased risk for keratoconus, with the frequency of 39.9% and 29% in patients and controls, respectively (OR?=?1.614, 95% CI: 1.119–2.326, p?=?0.011). Furthermore, the haplotype analysis revealed that the rs1800449G/rs2288393C is a protective factor against keratoconus (OR?=?0.425, 95% CI?=?0.296–0.609, p?=?0.001). Conversely, the +473A/rs2288393C (OR?=?3.703, 95% CI?=?2.230–6.149, p?=?0.001) and +473G/rs2288393G (OR?=?15.48, 95% CI?=?3.805–63.03, p?=?0.001) haplotypes were identified as risk factors for keratoconus.

Conclusion: Our study demonstrated that the LOX rs1800449 genotypes (AA and GA?+?AA) and allele (A) appears to confer risk for susceptibility to keratoconus.