Effects of prolonged exposure to low dose metformin in thyroid cancer cell lines

© Ivyspring International Publisher. Background: Thyroid cancer is generally associated with an excellent prognosis, but there is significant long-term morbidity with standard treatment. Some sub-types however have a poor prognosis. Metformin, an oral anti-diabetic drug is shown to have anti-cancer effects in several types of cancer (breast, lung and ovarian cancer). The proposed mechanisms include activation of the Adenosine Mono-phosphate-activated Protein Kinase (AMPK) pathway and inhibition of the mTOR pathway (which promotes growth and proliferation). By inhibiting hepatic gluconeogenesis and increasing glucose uptake by muscles, metformin decreases blood glucose and circulating Insulin levels. Aims: Explore the effect of metformin on the growth and proliferation of thyroid cancer cell lines. Methods: The effects of metformin on thyroid cancer cell lines (FTC-133, K1E7, RO82-W-1, 8305C and TT) and normal thyroid follicular cells (Nthy-ori 3-1) were investigated using the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay for cell proliferation; clonogenic assays FACS analysis for apoptosis and cell cycle, H2A.X phosphorylation (γH2AX) assay for DNA repair and scratch assay for cell migration. Results: Metformin inhibited cell proliferation and colony formation at 0.03 mM and above and inhibited cell migration at 0.3 mM. At concentrations of 0.1 mM and above metformin increased the percentage of apoptotic cells and induced cell cycle arrest in G0/G1 phase at minimum concentration of 0.3 mM. Unlike previous reports, no effect on DNA repair response was demonstrated. Conclusion: Metformin suppressed growth of all thyroid cancer cell lines, at concentrations considered to be within in the therapeutic range for diabetic patients on metformin (<0.3 mM)

Structure and Vibrational Spectra of Mononitrated Benzo [a] Pyrenes.

The molecules benzo[a]pyrene (BaP) and 1-, 3-, and 6-nitrobenzo[a]pyrene (1-NBaP, 3-NBaP, 6-NBaP) are currently of significant interest due to their presence in respirable combustion exhaust particulates and their mutagenic and carcinogenic properties. Structure−function correlations as well as spectroscopic signatures for trace analysis are necessary for these benzo[a]pyrene derivatives. In this paper, detailed infrared and Raman spectroscopic data of BaP and its three mononitrated isomers are provided for the first time. By utilizing density functional theory (DFT, B3LYP method with 6-311+G** basis set), the molecular geometries and the vibrational spectra are calculated. Good agreement is noted between the calculated and experimental geometry for BaP, and predictions of the vibrational data for all compounds are within ∼5 cm-1 of the experimental data. Normal mode assignments are proposed with particular emphasis on the nitro group vibrations. The geometrical distortions of the BaP structure upon nitro group substitution and correlations between structural parameters and vibrational data as well as structure−function relationships related to the mutagenicity of this important class of polycyclic aromatic hydrocarbons are discussed

Trapping cold atoms using surface-grown carbon nanotubes

We present a feasibility study for loading cold atomic clouds into magnetic traps created by single-wall carbon nanotubes grown directly onto dielectric surfaces. We show that atoms may be captured for experimentally sustainable nanotube currents, generating trapped clouds whose densities and lifetimes are sufficient to enable detection by simple imaging methods. This opens the way for a novel type of conductor to be used in atomchips, enabling atom trapping at sub-micron distances, with implications for both fundamental studies and for technological applications

Stability study of thymoquinone, carvacrol and thymol using HPLC-UV and LC-ESI-MS

The aim of this study was to investigate the stability of three major antioxidants of Nigella sativa: thymoquinone (TQ), carvacrol (CR) and thymol (THY), under different stress conditions using HPLC and LC-MS/MS. Forced degradation for each compound was performed under different conditions, including oxidation, hydrolysis, photolysis and thermal decomposition. The results showed that both CR and THY were stable under the studied conditions, whereas TQ was not affected by acidic, basic and oxidative forced conditions but the effect of light and heat was significant. The degradation products of TQ were further investigated and characterized by LC-MS/MS. HPLC-UV method has been fully validated in terms of linearity and range, the limit of detection and quantitation, precision, selectivity, accuracy and robustness. The method was successfully applied to quantitative analysis of the principal antioxidants of Nigella sativa TQ, CR and THY in different phytopharmaceuticals

Double vitrification and warming does not compromise the chance of live birth after single unbiopsied blastocyst transfer

STUDY QUESTION: Does double vitrification and thawing of an embryo compromise the chance of live birth after a single blastocyst transfer? SUMMARY ANSWER: The live birth rate (LBR) obtained after double vitrification was comparable to that obtained after single vitrification. WHAT IS KNOWN ALREADY: Double vitrification-warming (DVW) is commonly practiced to accommodate surplus viable embryos suitable for transfer, to allow retesting of inconclusively diagnosed blastocysts in preimplantation genetic testing (PGT), and to circumvent limitations associated with national policies on embryo culture in certain countries. Despite its popularity, the evidence concerning the impact of DVW practice on ART outcomes is limited and lacking credibility. This is the first thorough investigation of clinical pregnancy and LBR following DVW in the case where the first round of vitrification occurred at the zygote stage and the second round occurred at the blastocyst stage in the absence of biopsy. STUDY DESIGN, SIZE, DURATION: This is a retrospective observational analysis of n = 407 single blastocyst transfers whereby embryos created by IVF/ICSI were vitrified-warmed once (single vitrification-warming (SVW) n = 310) or twice (DVW, n = 97) between January 2017 and December 2021. PARTICIPANTS/MATERIALS, SETTING, METHODS: In the SVW group, blastocysts were vitrified on Day 5/6 and warmed on the day of embryo transfer (ET). In the DVW group, two pronuclear (2PN) zygotes were first vitrified-warmed and then re-vitrified on Day 5/6 and warmed on the day of ET. Exclusion criteria were ETs from PGT and vitrified-warmed oocyte cycles. All of the ETs were single blastocyst transfers performed at the University Hospital Zurich in Switzerland following natural or artificial endometrial preparation. MAIN RESULTS AND THE ROLE OF CHANCE: The biochemical pregnancy rate, clinical pregnancy rate (CPR), and LBR were all comparable between the DVW and SVW groups. The CPR for DVW was 44.3% and for SVW it was 42.3% (P = 0.719). The LBR for DVW was 30.9% and for SVW it was 28.7% (P = 0.675). The miscarriage rate was additionally similar between the groups: 27.9% for DVW and 32.1% for SVW groups (P = 0.765). LIMITATIONS, REASONS FOR CAUTION: The study is limited by its retrospective nature. Caution should be taken concerning interpretation of these findings in cases where DVW occurs at different stages of embryo development. WIDER IMPLICATIONS OF THE FINDINGS: The result of the present study on DVW procedure provides a framework for counselling couples on their chance of clinical pregnancy per warming cycle. It additionally provides confidence and reassurance to laboratory professionals in certain countries where national policies limit embryo culture strategies making DVW inevitable. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the University Research Priority Program ‘Human Reproduction Reloaded’ of the University of Zurich. The authors have no conflict of interest related to this study to declare

Higher miscarriage rate in subfertile women with endometriosis receiving unbiopsied frozen-warmed single blastocyst transfers

Background: Assisted reproductive technology treatment is recommended to overcome endometriosis-associated infertility but current evidence is controversial. Endometriosis is associated with lower antral follicle count (AFC) and oocyte yield but similar clinical outcomes compared to controls. Unaffected ovarian stimulation response and embryological outcomes but lower clinical pregnancy and live birth rates and higher miscarriage rates have been reported, implying direct impact on endometrial receptivity. With evidence emerging on the benefit of frozen-warmed and blastocyst stage transfer, we investigated ART outcomes in endometriosis using homogeneous case-control groups.Methods: This is a retrospective observational case-control study including n = 66 frozen-warmed unbiopsied single blastocyst transfers of patients with endometriosis and n = 96 of women exhibiting idiopathic sterility. All frozen-warmed transfers followed artificial endometrial preparation. Results: In control women, the mean number of oocytes recovered at oocyte pick up was higher compared to women with endometriosis (15.3 ± 7.1 vs. 12.7 ± 5.2, p = 0.025) but oocyte maturation index (mature oocytes/total oocytes at oocyte pick up) was significantly higher for endometriosis (48.2% vs. 34.0%, p = 0.005). The same was shown for the subgroup of 44 endometriosis patients after endometrioma surgery when compared with controls (49.1% vs. 34.0%, p = 0.014). Clinical pregnancy rate was not higher in endometriosis but was close to significance (47.0% vs. 32.3%, p = 0.059) while live birth rate was comparable (27.3% vs. 32.3%, p = 0.746). Miscarriage rate was higher in the endometriosis group (19.7% vs. 7.3%, p = 0.018). A significantly higher AFC was observed in the control group in comparison with the endometriosis group (16.3 ± 7.6 vs. 13.4 ± 7.0, p = 0.014). Live birth rate did not differ when comparing all endometriosis cases (p = 0.746), ASRM Stage I/II and Stage III/IV (p = 0.348 and p = 0.888) with the control group but the overall pregnancy rate was higher in ASRM Stage I/II (p = 0.034) and miscarriage rate was higher in ASRM Stage III/IV (p = 0.030) versus control.Conclusion: Blastocyst transfers in women with endometriosis originate from cycles with lower AFC but higher share of mature oocytes than in control women, suggesting that endometriosis might impair ovarian reserve but not stimulation response. A higher miscarriage rate, independent of blastocyst quality may be attributed to an impact of endometriosis on the endometrium beyond the timing of implantation

No widespread dissemination of Chlamydia trachomatis diagnostic-escape variants and the impact of Neisseria gonorrhoeae positivity on the Aptima Combo 2 assay

OBJECTIVES: A Finnish Chlamydia trachomatis (CT) new variant was detected in 2019 that escaped detection in the Hologic Aptima Combo 2 (AC2) assay due to a C1515T mutation in the CT 23S rRNA target region. Reflex testing of CT-negative/CT-equivocal specimens as well as those positive for Neisseria gonorrhoeae (NG) with the Hologic Aptima CT (ACT) assay was recommended to identify any CT variants. METHODS: From June to October 2019, specimens with discrepant AC2/ACT CT results were submitted to Public Health England and screened for detectable CT DNA using an inhouse real-time (RT)-PCR. When enough DNA was present, partial CT 23S rRNA gene sequencing was performed. Analysis of available relative light units and interpretative data was performed. RESULTS: A total of 317 discordant AC2/ACT specimens were collected from 315 patients. Three hundred were tested on the RT-PCR; 53.3% (n=160) were negative and 46.7% (n=140) were positive. Due to low DNA load in most specimens, sequencing was successful for only 36 specimens. The CT 23S rRNA wild-type sequence was present in 32 specimens, and two variants with C1514T or G1523A mutation were detected in four specimens from three patients. Of the discordant specimens with NG interpretation, 36.6% of NG-negative/CT-negative AC2 specimens had detectable CT DNA on the inhouse RT-PCR vs 53.3% of NG-positive/CT-negative specimens. CONCLUSIONS: No widespread dissemination of AC2 diagnostic-escape CT variants has occurred in England. We however identified the impact of NG positivity on the discordant AC2/ACT specimens; a proportion appeared due to NG positivity and the associated NG signal, rather than any diagnostic-escape variants or low DNA load. Several patients with gonorrhoea may therefore receive false-negative AC2 CT results. Single diagnostic targets and multiplex diagnostic assays have their limitations such as providing selection pressure for escape mutants and potentially reduced sensitivity, respectively. These limitations must be considered when establishing diagnostic pathways

Oligodendroglioma patient survival is associated with circulating B-cells and age

BackgroundVariations in survival among patients with oligodendroglioma are unexplained by known prognostic factors. To assess the impact of peripheral immune profiles on prognosis, we applied immunomethylomics analyses-DNA methylation of archived whole blood samples, to characterize immune cells.MethodsWe compared the proportions of immune cells from patients with oligodendroglioma to other glioma subtypes and controls. We used recursive partitioning analysis (RPA) within the oligodendrogliomas to correlate with survival.ResultsPatients with oligodendrogliomas (141) were median age at diagnosis of 44 years; 57% male; 75% White; 60% prior chemotherapy; and 25% on dexamethasone at sample collection. Patients with oligodendrogliomas had immune profiles more similar to controls than other glioma subtypes, though with notably lower B-cells. RPA of patients with oligodendrogliomas delineated 2 survival groups based on an interaction between age and B-naïve cells. Patients with longer survival (median 24.2 years) were ≤42 years of age with higher B-naïve cells versus worse survival (median 16.9 years) who were ≤42 years of age with lower B-naïve cells or &gt;42 years of age (P = .00032). Patients with worse survival also had lower CD4- and CD8-naïve T-cells. Similar immune profiles were observed in an independent cohort of oligodendroglioma patients prior to surgery.ConclusionsPeripheral blood immune profiles in oligodendroglioma suggested that younger patients with lower B-naïve cells experienced shorter survival. Though our findings lack of validation cohort and use a heterogenous patient population, they suggest peripheral blood immune profiles may be prognostic for patients with glioma and warrant further investigation