True coincidence summing correction for a BEGe detector in close geometry measurements

The true coincidence summing correction factor for a Broad Energy Germanium detector has been calculated at far and close geometry set-up using radioactive γ-ray sources. The correction factors were calculated using both experimental and analytical methods. Geant4 simulation was done to calculate the full-energy peak and total efficiencies of the detector. Standard, as well as fabricated mono-energetic γ-ray sources, were used for the γ-ray efficiency measurements. The simulated efficiencies of mono-energetic γ-ray sources were matched to the experimental γ-ray efficiencies by optimizing the detector parameters. The same parameters were used to obtain the full-energy peak and total efficiencies for γ-rays of current interest. Analytical and experimental correction factors were found to agree well with each other. The coincidence summing effect is found to be significant for source-to-detector distances less than 5 cm.

Pathologist's perspectives on reporting of tumour budding in colorectal cancer

Purpose

Tumour budding (TB) is an important adverse prognostic factor in colon cancer, which can also guide adjuvant treatment in stage II colorectal carcinoma. The International Tumor Budding Consensus Conference (ITBCC) recommended a three-tiered scoring system to streamline the scoring of budding across the globe. The goal of this survey is to understand the variation in reporting practice, globally.

Methods

A short survey was designed as an online questionnaire and shared via social media platforms and emails to pathology society groups in various countries.

Results

A majority of the 294 respondents (186/294; 63.3%) report budding in colorectal carcinoma. This figure differed significantly from 53.4% in Asia to 97.4% in North America. The most common (56.4%) reason for not reporting TB was because it is yet not a mandatory recommendation in the various datasets (e.g. The College of American Pathologists). The majority (78.9%) of the people who were reporting TB, used the ITBCC scoring system (scoring on a single hotspot 20× field). Most used 10× objective for screening (88.7%) and scored only at the invasive front (88.7%). Immunohistochemistry (8.6%) or deeper cuts (24.2%) were rarely used. TB scoring took 10 minutes or less in most (87.1%).

Conclusion

Though budding is well accepted among specialist gastrointestinal pathologists, it is still not universally accepted as an important prognostic parameter across the globe. The hesitancy for reporting is due to a combination of lack of clinical demand and extra effort and time involved in counting the ITBCC score.

Poor survival after resection of early gastric cancer: extremes of survivorship analysis reveal distinct genomic profile

A subset of patients with early gastric cancer demonstrate early recurrence and poor survival despite margin-negative resection. This study used an extremes-of-survivorship approach to identify an association between TP53 hotspot mutations co-occurring with loss of heterozygosity and unexpectedly poor survival in early gastric cancer. This distinct genomic profile may be a novel biomarker of poor survival in patients with completely resected early gastric cancer, and warrants large-scale validation. Promising, validation needed.

Optimal Blending of PbSe and CdSe in Polycrystalline PbCdSe Nanocomposite Film: Improved Carrier Multiplication and Enhanced Photoconversion Efficiency

The present work reports galvanostatic electro-co-deposition of n-PbCdSe semiconductor (SC) films on FTO substrate from the respective precursors. Self-designed matrices were formulated at variable concentrations of Pb²⁺ in the deposition medium. The semiconductor films constitute an intermixed structure of close-packed PbSe and CdSe nanoparticles (NPs), and the band gap (E_g) was effectively tuned in the range 0.99-1.47 eV for the variable compositions. Energy dispersive spectroscopy studies revealed that Cd exists in low level in the film matrix compared to Pb, presumably due to competitive deposition kinetics of the two chalcogenide compounds and the crystallite sizes determined from XRD studies, ranges between 15 and 12 nm, which corresponds to the size quenching of SC-NPs with increased Pb²⁺ concentration. The durability studies identify the most stable film developed at 0.025 M Pb²⁺ concentration. PbSe materials are typically characterized with impact ionization which effectively induces carrier multiplication (CM) in the quasi Type-II PbCdSe composite, exhibiting reasonably high photoconversion efficiency (PCE) of 6.14% with current output of 19.2 mA cm^-2 for the optimal PbCdSe film.

Reporting of tumor budding in colorectal adenocarcinomas using ×40 objective: A practical approach for resource constrained set-ups

CONTEXT

Tumor budding (TBud) is recognized as a poor prognostic marker in colorectal cancer (CRC) with important treatment implications in Stage II cancers and malignant polyps. There are multiple propositions for bud count reporting but without an uniformly accepted system. The International TBud consensus conference (ITBCC) proposed mandatory reporting of budding on the single worst ×20 high power field (0.785 mm² area) with a 3-tier scoring system (low/intermediate/high for 0-4, 5-9, and ≥10 buds/×20 field).

AIMS

Due to the lack of availability of ×20 objective, we aimed to validate a simple ×40 field count (0.236 mm² area) for wider applicability.

METHODS

Bud count was done on hematoxylin and eosin-stained slides of 92 archived cases of colon cancer on the worst ×20 and ×40 fields (0.95 mm² and 0.236 mm² area) (hotspot method). Count for 0.785 mm² area was calculated using ITBCC normalization factor of 1.2. Interobserver variability between two observers was assessed. Score groups for ×20 field and proposed score groups for 40× field (low/intermediate/high for 0-1, 2-4 and ≥5 buds) were compared with disease-free survival.

RESULTS

High bud score was seen in 20.6% and 31.5% cases, respectively, using the ×20 and ×40 methods. High interobserver concordance was noted (ICC 0.95). Both the ITBCC bud score and our proposed 40× scoring correlated significantly with prognosis (P = 0.030, log-rank test).

CONCLUSIONS

: In centers lacking 20× objective, we propose using the worst 40× hotspot method for reporting of budding for all CRCs as a simple, reproducible and prognostically significant scoring system.

Multi-elemental chalcogeniden-BiCdSe films grown under controlled depth voltammetry: improved photo-electrochemical behaviour toward energy conversion

In this study, a combinatorial approach was developed for fabricating nanostructured composite semiconductor matrices, which exhibited promising photo-response, appreciable photo-current potential and enhanced energy conversion efficiency.

Painful sex (dyspareunia) in women: prevalence and associated factors in a British population probability survey

Objective

To estimate the prevalence of painful sex among women in Britain, and to explore associated sexual, relationship and health factors that should be considered in assessment.

Design

Multi‐stage, clustered and stratified population probability sample survey, using computer‐assisted self‐interview. Sample frame was the British Postcode Address File.

Setting

Participants interviewed at home between 2010 and 2012.

Sample

A total of 15 162 adults aged 16–74 years (8869 women). Data reported from 6669 sexually active women.

Methods

Age‐adjusted logistic regressions to examine associations between painful sex and indicators of sexual, relational, mental and physical health.

Main outcome measure

Physical pain as a result of sex for ≥3 months in the past year, plus measures of symptom severity.

Results

Painful sex was reported by 7.5% (95% CI 6.7–8.3) of sexually active women, of whom one‐quarter experienced symptoms very often or always, for ≥6 months, and causing distress. Reporting painful sex was strongly associated with other sexual function problems, notably vaginal dryness (age adjusted odds ratio 7.9; 6.17–10.12), anxiety about sex (6.34; 4.76–8.46) and lacking enjoyment in sex (6.12; 4.81–7.79). It was associated with sexual relationship factors [such as not sharing same level of interest in sex (2.56; 1.97–3.33)], as well as with adverse experiences such as non‐volitional sex (2.17; 1.68–2.80). Associations were also found with measures of psychological and physical health, including depressive symptoms (1.68; 1.28–2.21).

Conclusion

Painful sex is reported by a sizeable minority of women in Britain. Health professionals should be supported to undertake holistic assessment and treatment which takes account of the sexual, relationship and health context of symptoms.

Tweetable abstract

Painful sex—reported by 7.5% of women in Britain—is linked to poorer sexual, physical, relational and mental health.

Painful sex–reported by 7.5% of women in Britain–is linked to poorer sexual, physical, relational and mental health.

This article includes Author Insights, a video abstract available at https://vimeo.com/rcog/authorinsights14518.

CdTe nanoparticles decorated titania for dye sensitized solar cell: a novel co-sensitizer approach towards highly efficient energy conversion

A hybrid TiO₂–CdTe multi-layer matrix fabricated for validation in a dye sensitized solar cell (DSSC) operating with N3 dye as the sensitizer.

Catalytic Intervention of MoO3 toward Ethanol Oxidation on PtPd Nanoparticles Decorated MoO3-Polypyrrole Composite Support

Ethanol oxidation reaction has been studied in acidic environment over PtPd nanoparticles (NPs) grown on the molybdenum oxide-polypyrrole composite (MOPC) support. The attempt was focused on using reduced Pt loading on non-carbon support for direct ethanol fuel cell (DEFC) operated with proton exchange membrane (PEM). As revealed in SEM study, a molybdenum oxide network exists in polypyrrole caging and the presence of metal NPs over the composite matrix is confirmed by TEM analysis. Further physicochemical characterizations such as XRD, EDAX, and XPS are followed in order to understand the surface morphology and composition of the hybrid structure. Electrochemical techniques such as voltammetry, choroamperometry, and impedance spectroscopy along with performance testing of an in-house-fabricated fuel cell are carried out to evaluate the catalytic activity of the materials for DEFC. The reaction products are estimated by ion chromatographic analysis. Considering the results obtained from the above characterization procedures, the best catalytic performance is exhibited by the Pt-Pd (1:1) on MOPC support. A clear intervention of the molybdenum oxide network is strongly advocated in the EOR sequence which increases the propensity of the reaction by making the metallites more energy efficient in terms of harnessing sufficient numbers of electrons than with the carbon support.

Trends in the use of emergency contraception in Britain: evidence from the second and third National Surveys of Sexual Attitudes and Lifestyles

OBJECTIVE

To examine the changes in the prevalence of, and the factors associated with, the use of emergency contraception (EC) in Britain between 2000 and 2010, spanning the period of deregulation and increase in pharmacy supply.

DESIGN

Cross-sectional probability sample surveys.

SETTING AND POPULATION

British general population.

METHODS

Data were analysed from the second and third British National Surveys of Sexual Attitudes and Lifestyles (Natsal), undertaken in 1999-2001 and 2010-12. Univariate and logistic regression analyses were used to measure change in EC use amongst sexually active women aged 16-44 years not intending pregnancy.

MAIN OUTCOME MEASURES

Prevalence of EC use and factors associated with use.

RESULTS

Of the 5430 women surveyed in 1999-2001 and the 4825 women surveyed in 2010-12, 2.3 and 3.6%, respectively, reported using EC in the year prior to interview (P = 0.0019 for change over time). The prevalence of EC use increased amongst single women and those with higher educational attainment (adjusted odds ratio, aOR 1.51; 95% confidence interval, 95% CI 1.04-2.20; P = 0.0308). Increases in EC use were generally greater among women without behavioural risk factors, such as those with no history of abortion within 5 years (aOR 1.57; 95% CI 1.17-2.12; P = 0.0029), or those whose first heterosexual intercourse occurred after the age of 16 years (aOR 1.68; 95% CI 1.21-2.35; P = 0.0021). The increase in EC use was also more marked among women usually accessing contraception from retail sources than among those doing so from healthcare sources, which may reflect a use of condoms amongst EC users.

CONCLUSION

The increase in EC use among women in Britain in the first decade of the 21st century was associated with some, but not all, risk factors for unplanned pregnancy. Advice and provision may need to be targeted at those at highest risk of unplanned pregnancy.

TWEETABLE ABSTRACT

Despite pharmacy access, only a small rise in emergency contraception use has been seen in Britain over 10 years.

Prevalence of infertility and help seeking among 15 000 women and men

STUDY QUESTION

What is the prevalence of infertility and of help seeking among women and men in Britain?

SUMMARY ANSWER

One in eight women and one in ten men aged 16–74 years had experienced infertility, defined by unsuccessfully attempting pregnancy for a year or longer, and little more than half of these people sought medical or professional help.

WHAT IS KNOWN ALREADY

Estimates of infertility and help seeking in Britain vary widely and are not easily comparable because of different definitions and study populations.

STUDY DESIGN, SIZE, DURATION

A cross-sectional population survey was conducted between 2010 and 2012 with a sample of 15 162 women and men aged 16–74 years.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Participants completed the Natsal-3 questionnaire, using computer-assisted personal interviewing (CAPI) and computer-assisted self-interview (CASI).

MAIN RESULTS AND THE ROLE OF CHANCE

The reported prevalence of infertility was 12.5% (CI 95% 11.7–13.3) among women and 10.1% (CI 95% 9.2–11.1) among men. Increased prevalence was associated with later cohabitation with a partner, higher socio-economic status and, for those who had a child, becoming parents at older ages. The reported prevalence of help seeking was 57.3% (CI 95% 53.6–61.0) among women and 53.2% (CI 95% 48.1–58.1) among men. Help seekers were more likely to be better educated and in higher status occupations and, among those who had a child, to have become parents later in life.

LIMITATIONS, REASONS FOR CAUTION

These data are cross-sectional so it is not possible to establish temporality or infer causality. Self-reported data may be subject to recall bias.

WIDER IMPLICATIONS OF THE FINDINGS

The study provides estimates of infertility and help seeking in Britain and the results indicate that the prevalence of infertility is higher among those delaying parenthood. Those with higher educational qualifications and occupational status are more likely to consult with medical professionals for fertility problems than others and these inequalities in help seeking should be considered by clinical practice and public health.

STUDY FUNDING/COMPETING INTEREST(S)

Funding was provided by grants from the Medical Research Council and the Wellcome Trust, with support from the Economic and Social Research Council and the Department of Health. AMJ is a Governor of the Wellcome Trust. Other authors have no competing interests.

Voltammetric deposition of BiCdTe composite films with improved functional properties for photo-electrochemical cells

n-Type BiCdTe nanostructured films produced by periodic voltammetry exhibit high photo-conversion efficiency and significantly promote charge transport across the electrode/electrolyte interface.

Acute kidney injury and dermonecrosis after Loxosceles reclusa envenomation

Spiders of the Loxosceles species can cause dermonecrosis and acute kidney injury (AKI). Hemolysis, rhabdomyolysis and direct toxin-mediated renal damage have been postulated. There are very few reports of Loxoscelism from India. We report a case of AKI, hemolysis and a "gravitational" pattern of ulceration following the bite of the brown recluse spider (Loxosceles spp).

Temporal and spatial changes in phenolic compounds in response to Fusarium wilt in chickpea and pigeonpea

Plant phenolic compounds are known to play an important role in innate plant defense and are reported to show temporal and spatial changes in response to abiotic and biotic stress including invading pathogens. In the present study, spatial and temporal variations in phenolic compounds in response to infection by wilt pathogen, Fusarium oxysporum f. sp. ciceri (Foc) and Fusarium udum (Fud) were studied in wilt resistant and wilt susceptible cultivars of chickpea (Cicer arietinum L.) and pigeonpea (Cajanus cajan L. Millspaugh) (i) before the onset of wilt infection (S1 stage; 7 Days after sowing (DAS)), (ii) after the onset of wilt infection (S2 stage; 15 DAS) and (iii) at severe disease stage (S3 stage; 30 DAS), respectively and analyzed for association of total phenol with disease reaction. Under un—inoculated condition, maximum phenol content (21.8 mg gdw—1) was found in wilt resistant cultivars and minimum (16.5 mg gdw—1) in susceptible lines of chickpea. Wilt resistant cultivars of chickpea showed two fold increase in total phenolic content at the onset of infection. In case of pigeonpea, roots of resistant cultivars showed 2.27 fold increase in phenolics, but the increase was marginal in susceptible cultivars. In the present study, interaction between Fusarium and host plants was found to enhance defense responses against wilt disease in resistant cultivars of chickpea and pigeonpea.

Application of molecular markers for genetic discrimination of Fusarium wilt pathogen races affecting chickpea and pigeonpea in major regions of India

(foc) and Fusarium udum (Fud) collected from major pulse growing regions of India. Out of 247 bands produced by 24 Randomly Amplified Polymorphic DNA (RAPD) primers in Foc isolates, 210 (85%) were polymorphic. A maximum of 14 amplicons were generated by primer OPF 05 whereas minimum 7 amplicons were generated by primer K7. A total of 24 alleles were produced by twelve Simple Sequence Repeats (SSR) primers with an average of two alleles per marker in foc isolates. The maximum number of 4 alleles was obtained with primer SSR 12. SSR amplicon size ranged from 100 to 400 bp. The Unweighted Pair Group Method with Arithmetic average (UPGMA) cluster analysis based on RAPD and SSR profiles grouped the fourteen foc isolates into four major clusters. The universal Inter Transcribed Spacer (ITS) primer pair amplified 630 bp bands in all fourteen foc isolates while significant length polymorphism was obtained only when analysed by restriction digestion with EcoRI and MspI enzymes. The cluster analysis of ITS—RFLP grouped all 14 Foc isolates into three major clusters. Twenty four RAPD primers generated a total of 226 bands (ranging 0.3 to 3.0 kb) in Fusarium udum with an average of 9.4 bands per primer and a total of 27 alleles were produced by twelve SSR primers with an average of 2.25 alleles per marker. All isolates amplified a single band ranging from 100 to 450 bp. The universal ITS primer pair amplified 650 bp bands in all fourteen fud isolates while significant length polymorphism was obtained only when analysed by restriction digestion with EcoRI and Hind III enzymes. The cluster analysis of ITS—RFLP grouped all 14 Fud isolates into three major clusters. The cluster analysis using various markers show the grouping of Fusarium isolates strictly according to their cultural characteristics and degree of pathogenicity and not the geographical origin. This information will be helpful for pathologists and plant breeders to design effective resistance breeding programs in chickpea and pigeonpea taking into account the diversity in wilt pathogen.

A study of the surface erosion of zircaloy material during laser ablation process by thin layer activation technique

The thin layer activation (TLA) technique was applied to study the surface erosion of zircaloy clad material during laser ablation process by producing a suitable γ-ray emitting radioisotope in the clad surface using 40 MeV α-particles. This paper reports the rate of surface erosion of zircaloy as a function of deposited laser energy in the range of a few hundred of millijoules to a few kilojoule. The minimum detection limit was found to be 80 ± 25 nm in the measurement of surface loss of material due to laser exposure by TLA technique.

An Over-View of Tuberculosis of Female Genital Tract With Reference To Experience in a Medical College in Rural Set-Up in West Bengal: A Retrospective Two Year Study

Aim: To determine frequency of female genital tract (FGT) tuberculosis (TB) in the gynecological biopsies received in the Department of pathology of a peripheral medical college. Methods: This is a retrospective study conducted in the Department of Pathology of Burdwan Medical College & Hospital. Histopathological records of two year (2008-2010) were retrieved and searched for the cases of female genital tract TB. Relevant histopathological findings and clinical data were recorded and analyzed. Results: There were 1537 cases of gynecological biopsy and 9 cases were diagnosed as FGT tuberculosis based on histopathological and clinical findings. Ovarian benign cystic teratoma was seen in one case along with ipsilateral tuberculous salpingitis, one case showed B/L ovarian tuberculosis with involvement of both the tubes. Bilateral fallopian tubes were involved in 2 cases and endometrial tuberculosis was diagnosed in 5 cases with 1 case showing simultaneous involvement of the cervix. In one case omental biopsy received along with tubal specimen showed tuberculous granulomas. Conclusion: FGT tuberculosis was usually seen in  age 16-28 years and constituted 0.59% of total gynecological cases. Fallopian tubes, ovaries and endometrium and cervix were affected with the involvement of peritoneum or omentum, commonest being tuberculous endometritis. Histopathology, in association with clinical findings still remains gold standard for the diagnosis of FGT tuberculosis in our country despite advancement in diagnostic modalities; however, incidental histological detection in clinically unanticipated cases is not an uncommon event. DOI: http://dx.doi.org/10.3329/bjms.v11i3.11719 Bangladesh Journal of Medical Science Vol. 11 No. 03 July’12  

Applications of thin layer activation technique for the measurement of surface loss of materials: an Indian perspective

Thin layer activation (TLA) technique is a powerful nuclear technique based on the production of a radioisotope in the surface of a material by a charged particle induced nuclear reaction, followed by an estimation of the loss of the activity which is a measure of the surface loss of materials in the range of nanometer to hundreds of micrometer in the fields of wear, corrosion or erosion. The technique has been found to be a very useful tool in the basic scientific research and industrial applications. The present review describes the basic principle of TLA technique, its characteristic features, methodology, scope, applications and various recent developments regarding its growing use. Some of our earlier TLA work carried out with α and heavy ion (16O) in various applied areas is also included here. Heavy ions were used because no other light ions (particularly protons) were available at our cyclotron.

Views and experiences of men who have sex with men on the ban on blood donation: a cross sectional survey with qualitative interviews

OBJECTIVE

To explore compliance with the UK blood services' criterion that excludes men who have had penetrative sex with a man from donating blood, and to assess the possible effects of revising this policy.

DESIGN

A random location, cross sectional survey followed by qualitative interviews.

SETTING

Britain.

PARTICIPANTS

1028 of 32,373 men in the general population reporting any male sexual contact completed the survey. Additional questions were asked of a general population sample (n=3914). Thirty men who had had penetrative sex with a man participated in the qualitative interviews (19 who had complied with the blood services' exclusion criterion and 11 who had not complied). Main outcome measure Compliance with the blood services' lifetime exclusion criterion for men who have had penetrative sex with a man.

RESULTS

10.6% of men with experience of penetrative sex with a man reported having donated blood in Britain while ineligible under the exclusion criterion, and 2.5% had donated in the previous 12 months. Ineligible donation was less common among men who had had penetrative sex with a man recently (in previous 12 months) than among men for whom this last occurred longer ago. Reasons for non-compliance with the exclusion included self categorisation as low risk, discounting the sexual experience that barred donation, belief in the infallibility of blood screening, concerns about confidentiality, and misunderstanding or perceived inequity of the rule. Although blood donation was rarely viewed as a "right," potential donors were seen as entitled to a considered assessment of risk. A one year deferral since last male penetrative sex was considered by study participants to be generally feasible, equitable, and acceptable.

CONCLUSIONS

A minority of men who have sex with men who are ineligible to donate blood under the current donor exclusion in Britain have nevertheless done so in the past 12 months. Many of the reasons identified for non-compliance seem amenable to intervention. A clearly rationalised and communicated one year donor deferral is likely to be welcomed by most men who have sex with men.

Characterization of Pt-Pd/C Electrocatalyst for Methanol Oxidation in Alkaline Medium

The Pt-Pd/C electrocatalyst was synthesized on graphite substrate by the electrochemical codeposition technique. The physicochemical characterization of the catalyst was done by SEM, XRD, and EDX. The electrochemical characterization of the Pt-Pd/C catalyst for methanol electro-oxidation was studied over a range of NaOH and methanol concentrations using cyclic voltammetry, quasisteady-state polarization, chronoamperometry, and electrochemical impedance spectroscopy. The activity of methanol oxidation increased with pH due to better OH species coverage on the electrode surface. At methanol concentration (>1.0 M), there is no change in the oxidation peak current density because of excess methanol at the electrode surface and/or depletion of OH−at the electrode surface. The Pt-Pd/C catalyst shows good stability and the low value of Tafel slope and charge transfer resistance. The enhanced electrocatalytic activity of the electrodes is ascribed to the synergistic effect of higher electrochemical surface area, preferred OH−adsorption, and ad-atom contribution on the alloyed surface.

MicroRNA-221/222 confers tamoxifen resistance in breast cancer by targeting p27(kip1)

Abstract #3023

Background: Breast cancer is the most common malignancy in women, accounting for 31% of all female cancers. Over two-thirds of breast cancers exhibit high concentrations of estrogen receptor, which contribute to tumor growth and progression. Blocking the steroid hormone pathway with tamoxifen and/or oophorectomy has been shown to be effective in this patient population. However, approximately 30% of the breast cancer is resistant to tamoxifen. Recent studies have highlighted the key regulatory roles of microRNAs (miR) in all fundamental cellular processes in animals and plants including primary human cancers. We hypothesized that alteration in the expression of specific miRs in breast cancer could contribute to tamoxifen resistance.
 Methods: To test this hypothesis, we performed microRNA microarray analysis using MCF-7 cell lines that are either sensitive (parental) or resistant to tamoxifen (4-hydroxy tamoxifen resistant-OHTR). Using Real-time RT-PCR we validated altered expression of the miRs in both the cell culture model and the primary human breast cancer tissues. Cells overexpressing miR-221/222 or p27(kip1) were created by transfection of mammalian expression vectors using Lipofectamine2000 followed by G418 selection. Cell viability upon tamoxifen treatment was measured by MTT assay, extent of apoptosis was monitored by Western blot analysis of PAPR and Caspase cleavage and cell cycle profile was studied using Flow cytometry.
 Results: Eight miRs were found to be significantly upregulated while seven miRs were significantly down-regulated in the OHTR cells compared to parental MCF-7 cells. The increased expression of three upregulated (miR-221, miR-222 and miR-181) and three downregulated (miR-21, miR-342 and miR-489) miRs was later validated in the cell lines by real-time RT-PCR. In addition, the level of miR-221 and miR-222 was significantly elevated in Her2/neu(+) primary human breast cancer tissues, compared to Her2/neu(-) tissue samples. The Her2/neu expressing tumors are known to be relatively resistant to endocrine therapy. Ectopic expression of miR-221/miR-222 in parental MCF-7 cells rendered the cells more tolerant to tamoxifen than the control cells. The cell cycle inhibitor p27/Kip1, a known target of miR-221/miR-222 was significantly reduced in both OHTR cells and miR-221/222 overexpressing MCF-7 cells, which was consistent with the upregulation of the miRs. Ectopic expression of p27/Kip1 in the resistant OHTR cells enhanced cell death when exposed to tamoxifen.
 Conclusion: This study has revealed a specific miR signature for the tamoxifen-resistant breast cancer and an important cell cycle inhibitor target of the altered miR, which could be used as a prognostic marker for the drug-resistant breast cancer. Further studies of other miRs differentially expressed in tamoxifen resistant cell lines, will help us not only in identifying such patients but also may serve as a therapeutic target in the future.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 3023.

Aberrant nucleocytoplasmic localization of the retinoblastoma tumor suppressor protein in human cancer correlates with moderate/poor tumor differentiation

Inactivation of the retinoblastoma (RB) tumor suppressor pathway, via elevated cyclin-dependent kinase (CDK) activity, is observed in majority of human cancers. Since CDK deregulation is evident in most cancer cells, pharmacological CDK inhibition has become an attractive therapeutic strategy in oncology. We recently showed that an oncogenic CDK4(R24C) mutation alters the subcellular localization of the normally nuclear RB phosphoprotein. Here, using 71 human cancer cell lines and over 300 primary human cancer tissues, we investigated whether changes in RB subcellular localization occur during human cancer progression. We uncover that diverse human cancers and their derived cell lines, particularly those with poor tumor differentiation, display significant cytoplasmic mislocalization of ordinarily nuclear RB. The nucleocytoplasmically distributed RB was derived via CDK-dependent and Exportin1-mediated nuclear export. Indeed, cytoplasmically mislocalized RB could be efficiently confined to the nucleus by pharmacologically reducing CDK activity or by inhibiting the Exportin1-mediated nuclear export pathway. Our observations uncover a post-translational CDK-dependent mechanism of RB inactivation and suggest that cytoplasmically localized RB may harbor a tumor promoting function. We propose that RB inactivation, via aberrant nucleocytoplasmic transport, may disrupt normal cell differentiation programs and accelerate the cancer process. These results are evidence that tumor cells modulate the protein transport machinery thereby making the protein transport process a viable therapeutic target.

Influenza virus infection induces metallothionein gene expression in the mouse liver and lung by overlapping but distinct molecular mechanisms

Metallothionein I (MT-I) and MT-II have been implicated in the protection of cells against reactive oxygen species (ROS), heavy metals, and a variety of pathological and environmental stressors. Here, we show a robust increase in MT-I/MT-II mRNA level and MT proteins in the livers and lungs of C57BL/6 mice exposed to the influenza A/PR8 virus that infects the upper respiratory tract and lungs. Interleukin-6 (IL-6) had a pronounced effect on the induction of these genes in the liver but not the lung. Treatment of the animals with RU-486, a glucocorticoid receptor antagonist, inhibited induction of MT-I/MT-II in both liver and lung, revealing a direct role of glucocorticoid that is increased upon infection in this induction process. In vivo genomic footprinting (IVGF) analysis demonstrated involvement of almost all metal response elements, major late transcription factor/antioxidant response element (MLTF/ARE), the STAT3 binding site on the MT-I upstream promoter, and the glucocorticoid responsive element (GRE1), located upstream of the MT-II gene, in the induction process in the liver and lung. In the lung, inducible footprinting was also identified at a unique gamma interferon (IFN-gamma) response element (gamma-IRE) and at Sp1 sites. The mobility shift analysis showed activation of STAT3 and the glucocorticoid receptor in the liver and lung nuclear extracts, which was consistent with the IVGF data. Analysis of the newly synthesized mRNA for cytokines in the infected lung by real-time PCR showed a robust increase in the levels of IL-10 and IFN-gamma mRNA that can activate STAT3 and STAT1, respectively. A STAT1-containing complex that binds to the gamma-IRE in vitro was activated in the infected lung. No major change in MLTF/ARE DNA binding activity in the liver and lung occurred after infection. These results have demonstrated that MT-I and MT-II can be induced robustly in the liver and lung following experimental influenza virus infection by overlapping but distinct molecular mechanisms.

Microsomal glutathione S-transferase (GST) isozymes in Aspergillus ochraceus TS: induction by 3-methylcholanthrene

Induction of microsomal glutathione S-transferase isozymes in Aspergillus ochraceus TS is reported. Among the inducers of mammalian drug-metabolising enzymes 3-methylcholanthrene, benzo(a)pyrene and polychlorinated biphenyl enhanced the microsomal GST activity quite considerably. On the other hand phenobarbital, beta-naphthoflavone and trans-stilbene oxide were almost without any effect. To our knowledge this seems to be the first report on induction of microsomal GST in lower eukaryotes. A significant increase (7.9 fold) in GST activity was observed with the cells induced by 3-methylcholanthrene. Moreover, three new GST isozymes were found to be present in 3-methylcholanthrene induced microsomes. The isozymes are basic in nature. The GST isozymes were found to be catalytically distinct from each other.

Onset of new catalytic activity in immobilized spores of Aspergillus ochraceus TS due to in situ germination: C17-C20 lysis accompanies 11 alpha-hydroxylation of steroid

The change in product pattern during transformation of progesterone by calcium alginate entrapped spores of Aspergillus ochraceus TS (A. ochraceus TS) due to germination in situ is reported. While progesterone was transformed exclusively to its 11 alpha-hydroxy derivative by both free and immobilized spores of A. ochraceus TS, the latter germinated in situ by yeast extract furnished 11 alpha-hydroxyprogesterone and C19 steroids during transformation under identical conditions. The characterization of metabolite(s) and the pathway proposed demonstrated that delta 1-dehydrogenation and lysis of C17-C20 bond are apparently two independent reactions. The change in product profile due to activation of immobilized spores is believed to be caused by accumulation of compatible solutes in the biocatalyst which had relatively low water content.