Measurement of natural radioactivity and dose rate assessment of terrestrial gamma radiation in the soil of southern Punjab, Pakistan

Activity concentrations of (226)Ra, (232)Th, (40)K and (137)Cs in soil samples collected from the most populous area of southern Punjab of Pakistan have been measured by gamma-ray spectrometry. The measured activity concentrations for these radionuclides are compared with the reported data from different other countries and it is found that measured activity concentrations are comparable with the worldwide measured average values reported by the UNSCEAR. Subsequently assessed radiological effects show that the mean radium equivalent activity (Ra(eq)) is 96.7 +/- 15.2 Bq kg(-1) and air absorbed dose rate (D) is 46.1 +/- 7.3 nGy h(-1). The values of internal and external radiation hazard indices are found to be less than unity. The annual effective radiation dose is calculated to be 0.28 +/- 0.05 mSv, which is well below the limit of 1.0 mSv y(-1) recommended by the International Commission on Radiological Protection, for the general public.

Determination of natural radioactivity in building materials used in the Rawalpindi/Islamabad area by gamma-ray spectrometry and instrumental neutron activation analysis

Samples of sand and manufactured building materials collected from the Rawalpindi/Islamabad area have been analyzed for the primordial natural radionuclides 238U, 232Th and 40K using gamma-ray spectrometry. The uranium and thorium contents have also been determined by instrumental neutron activation analysis (INAA). The specific activities of these radionuclides in the samples are compared with those of the world averages for soil. The comparison shows that, of the nine samples analyzed, only the three brick samples have higher activities than the world averages for soil. The specific activities in these materials, having a radium equivalent activity of less than 370 Bq kg-1, when evaluated for radiological effects show that all materials meet the external gamma-ray dose limitation of 1.5 mSv y-1. The gamma-spectrometric and INAA techniques complemented each other well in this study.

Measurement of natural radioactivity in bottled drinking water in Pakistan and consequent dose estimates

Natural radioactivity was determined in 11 different brands of commonly sold bottled drinking water in the federal capital Islamabad and Rawalpindi city of Pakistan using gamma spectrometry technique. Mean concentrations of 226Ra, 232Th and (40)K were found to be 11.3 +/- 2.3, 5.2 +/- 0.4 and 140.9 +/- 30.6 mBq l(-1), respectively. The annual cumulative effective doses due to all three natural radionuclides for different age groups of 1-5 y, 5-10 y, 10-15 y and adults (>or=18 y) were estimated to be 4.0, 3.4, 3.1 and 4.1 microSv y(-1), respectively. Among the three natural radionuclides, annual effective doses for all age groups from 226Ra were significant. Children in the age group of 1-5 y appeared to be at risk with respect to the annual effective doses from 226Ra as compared to the other age groups. Results obtained in this study are compared with the reported values from other countries of the world and it was observed that measured activity concentrations of three natural radionuclides in the bottled drinking water were lower than these values. Annual estimated effective doses for all four age groups from the intake of natural radionuclides in bottled drinking water were also found below the World Health Organisation (WHO) recommended limit of 0.1 mSv y(-1) as well as the average radiation dose of 0.29 mSv y(-1) received per head worldwide due to ingestion of natural radionuclides assessed by UNSCEAR (2000).

Nanoparticles as a Carrier System for Drug Delivery Across Blood Brain Barrier

Brain, the centre of the nervous system and an integral part the body, is protected by two anatomical and physiological barriers- Blood-Brain Barrier (BBB) and Blood-Cerebrospinal Fluid Barrier (BCSFB). Blood-Brain Barrier is a very complex and highly organized multicellular structure that shields the brain from harmful substances and invading organisms from the bloodstream and thus offering protection against various brain diseases and injuries. However, it also impede the effective delivery of drug to the brain, thus, preventing treatment of numerous neurological disorders. Even though various traditional approaches such as Intra-Cerebro-Ventricular (ICV) injection, use of implants, disruption of BBB and use of prodrugs have achieved some success in overcoming these barriers, researchers are continuously working for promising alternatives for improved brain drug delivery. Recent breakthroughs in the field of nanotechnology provide an appropriate solution to problems associated with these delivery approaches and thus can be effectively used to treat a wide variety of brain diseases. Thus, nanotechnology promises to bring a great future to the individuals with various brain disorders. This review provides a brief overview of various brain drug delivery approaches along with limitations. In addition, the significance of nanoparticles as drug carrier systems for effective brain specific drug delivery has been highlighted. To show the complexity of the problems to be overcome for improved brain drug delivery, a concise intercellular classification of the BBB along with general transport routes across it is also included.

Trace elements evaluation of some medicinal herbs by instrumental neutron activation analysis

Instrumental neutron activation analysis has been used for the analysis of seven varieties of medicinal herbs generally used by the people of South Asian region. Twenty-one trace elements (essential, toxic and non-essential) were determined. This data should not only be helpful in establishing the base-line values in these medicinal herbs but also in correlating their role as therapeutic agents. A comparison of our data with literature values shows variation in trace element contents of same species of different origin which can be attributed to ecological and geographical variations to some extent; however an exact interpretation demands further extensive investigations.

Inhibitory effect of 2-(piperidinoethoxyphenyl)-3-(4-hydroxyphenyl)-2H-benzo(b)pyran (K-1) on human primary endometrial hyperplasial cells mediated via combined suppression of Wnt/β-catenin signaling and PI3K/Akt survival pathway

Endometrial hyperplasia is a precursor to the most common gynecologic cancer diagnosed in women. Apart from estrogenic induction, aberrant activation of the Wnt/β-catenin signal is well known to correlate with endometrial hyperplasia and its carcinoma. The benzopyran compound 2-(piperidinoethoxyphenyl)-3-(4-hydroxyphenyl)-2H-benzo (b) pyran(K-1), a potent antiestrogenic agent, has been shown to have apoptosis-inducing activity in rat uterine hyperplasia. The current study was undertaken to explore the effect of the benzopyran compound K-1 on growth and Wnt signaling in human endometrial hyperplasial cells. Primary culture of atypical endometrial hyperplasial cells was characterized by the epithelial cell marker cytokeratin-7. Results revealed that compound K-1 reduced the viability of primary endometrial hyperplasial cells and expression of ERα, PR, PCNA, Wnt7a, FZD6, pGsk3β and β-catenin without affecting the growth of the primary culture of normal endometrial cells. The β-catenin target genes CyclinD1 and c-myc were also found to be reduced, whereas the expression of axin2 and Wnt/β-catenin signaling inhibitor Dkk-1 was found to be upregulated, which caused the reduced interaction of Wnt7a and FZD6. Nuclear accumulation of β-catenin was found to be decreased by compound K-1. K-1 also suppressed the pPI3K/pAkt survival pathway and induced the cleavage of caspases and PARP, thus subsequently causing the apoptosis of endometrial hyperplasial cells. In conclusion, compound K-1 suppressed the growth of human primary endometrial hyperplasial cells through discontinued Wnt/β-catenin signaling and induced apoptosis via inhibiting the PI3K/Akt survival pathway.

2,3-Diaryl-2H-1-benzopyran derivatives interfere with classical and non-classical estrogen receptor signaling pathways, inhibit Akt activation and induce apoptosis in human endometrial cancer cells

OBJECTIVES

The present study was undertaken to explore the mechanism of anti-proliferative action of benzopyran compound D1 (2-[piperidinoethoxyphenyl]-3-phenyl-2H-benzopyran) and its hydroxy-(D2) and methoxy-(D3) derivatives in Ishikawa and human primary endometrial adenocarcinoma cells.

METHODS

Transcriptional activation assays were performed using luciferase reporter system and cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The stage of cell cycle was determined by flow-cytometry and real time analysis of cyclinE1 and cdc2 genes. The apoptotic effects were measured by AnnexinV/PI staining and TUNEL. The expression of PCNA, cyclinD1, pAkt, XIAP, cleaved caspase-9, -3, PARP, Bax and Bcl2 were determined by immunoblotting. The caspase-3 activity and mitochondrial membrane potential were measured by colorimetric assay.

RESULTS

All three compounds inhibited E(2)-induced ERE- and AP-1-mediated transactivation and proliferation in endometrial adenocarcinoma cells dose-dependently. Compound D1 caused the arrest of cells in the G(2) phase while D2 and D3 caused arrest in G(1) phase of the cell cycle. All compounds interfered with Akt activation, decreased XIAP expression leading to an increased cleavage of caspase-9, -3, PARP, increased Bax/Bcl2 ratio and caspase-3 activity.

CONCLUSION

Findings suggest that benzopyran derivatives inhibit cellular proliferation via modulating ER-dependent classical and non-classical signaling mechanisms, interfere with Akt activation and induce apoptosis via intrinsic pathway in endometrial adenocarcinoma cells.

The anti-proliferative effect of 2-[piperidinoethoxyphenyl]-3-[4-hydroxyphenyl]-2H-benzo(b) pyran is potentiated via induction of estrogen receptor beta and p21 in human endometrial adenocarcinoma cells

In an effort to develop novel therapeutic agents for endometrial cancer, benzopyran derivatives synthesized at our institute display significant inhibitory activity on cellular growth in uterine cancer cells. The current study was undertaken to demonstrate and explore the estrogen receptor (ER) subtype mediated mechanism of action of benzopyran derivative 2-[piperidinoethoxyphenyl]-3-[4-hydroxyphenyl]-2H-benzo(b) pyran (K-1) in human endometrial cancer cells. K-1 competitively inhibited the estradiol binding to human ERα and ERβ and showed growth inhibitory activity in human endometrial Ishikawa, HEC1B and primary endometrial adenocarcinoma cells. Transient transactivation assays carried out in COS-1 cells have demonstrated the diminished ERα-ERE mediated- and induced the ERβ-ERE mediated-transactivation triggered by compound. It also induced ER-mediated transactivation of the cyclin-dependent kinase inhibitor (CDKI) p21(WAF-1) in both COS-1 cells and in Ishikawa cells. ERβ inducing effects of compound were blocked by ICI182,780. In endometrial adenocarcinoma cells, it induced ERβ and p21 expression significantly whereas the expression of fos, jun and ERα were significantly reduced. In addition, compound promoted ERα-β heterodimerization as observed in Ishikawa cells. These results demonstrate that the benzopyran compound suppressed the cellular growth via ERβ agonism, induction of p21 and via promoting the ERα-β heterodimerization, in addition to its antagonistic effects exerted on ERα, in human endometrial cancer cells. The study suggests that the dual action of benzopyran molecule may be of significant therapeutic value in ERα/β-positive cases of endometrial cancer.

A spirostanol glycoside from Cestrum nocturnum

A new steroidal saponin named nocturnoside A has been isolated from the methanolic extract of the fresh leaves of Cestrum nocturnum and has been characterized by 13C NMR spectroscopy to be 3-O-[beta-D-glucopyranosyl(1----3)-beta-D-glucopyranosyl(1----2)-beta-D- glucopyranosyl((3----1)-beta-D-xylopyranosyl)(1----4)-beta-D- galactopyranosyl) (25R)-spirost-5-ene-2 alpha,3 beta-diol.

Smokeless tobacco use and risk of oral cavity cancer

Background/aim

Smokeless tobacco has been associated with oral cavity cancer for several decades. The incidence of oral cavity cancer is higher in some parts of the world especially South and South-East Asia including Pakistan. The aim of current study was to evaluate the risk of oral cavity cancer among smokeless tobacco users in our country.

Materials and methods

A case-control study was conducted between November 2016 and September 2017. Patients diagnosed with oral cavity cancer receiving treatment were included as cases and the attendants of various cancer patients visiting the hospital during the study period were included in the study as controls. Odds ratios (OR) and 95% confidence intervals (CI) were calculated and all reported P-values were considered significant at < 0.05.

Results

The crude OR for the “ever smokeless tobacco users” among cases and controls came out to be 4.98 (95%CI; 2.76–9.01). The OR for snuff users among cases and controls was 4.82 (95%CI; 2.37–9.80) and that for betel leaf users was 4.42 (95%CI; 1.66–11.91) after adjusting for smoking and age.

Conclusion

Our study provided strong evidence for snuff and betel leaf to be independent risk factors for oral cavity cancer.

Quantitative analysis of ancient Chinese ceramic using k 0-instrumental neutron activation analysis

IAEA-CU-2006-06 (ancient Chinese ceramic) has been analyzed by k 0-INAA and the results for 31 elements are reported. Measurement on Si was done via the (n,p) reaction. The results of 23 elements are within ±10% of the target values and for 2 elements data are reported as information values. The results produce lower relative deviation if compared with the mean reported concentration values submitted by the laboratories participating in the proficiency test. The analysis involves full peak efficiency calibration of the HPGe detector for all counting geometries and characterization of neutron flux at the irradiation channel by determining thermal to epithermal flux ratio and epithermal flux shape factor using Au and Zr flux monitors. The u-score is less than 1 for majority of the elements.

Fission spectrum averaged cross section measurements of some neutron threshold reactions of relevance to medical radionuclide production

A resume is given of radiochemical measurements of nuclear reaction cross sections relevant to the production of some medically important radionuclides carried out at PINSTECH during the last decade. Systematic studies on fission neutron spectrum averaged cross sections of several threshold reactions, like (n, 2n), (n, p) and (n, α), on titanium, ruthenium, europium and dysprosium for the production of 45Ti, 96Tc, 153Sm and 153Gd are described.

Determination of natural radioactivity in building materials used in the Karachi area by γ-ray spectrometry and INAA

Samples of sand, stone and manufactured building materials collected from Karachi area have been analyzed for the primordial natural radionuclides 238U, 232Th and 40K using γ-ray spectrometry. The uranium and thorium contents have also been determined by instrumental neutron activation analysis (INAA). The specific activities in these materials, having a radium equivalent activity less than 370 Bq kg–1, when evaluated for radiological effects show that all materials meet the external γ-ray dose limitation of 1.5 mSv y–1. The γ-ray spectrometric and INAA techniques complemented each other well in this study.

Epidemiology and Treatment Outcomes of Sinonasal Tumors: A Single Institute's Experience in Pakistan

OBJECTIVE

To find the epidemiology and risk factors of sinonasal tumors and treatment outcomes in squamous cell carcinoma.

STUDY DESIGN

An observational study.

PLACE AND DURATION OF STUDY

The Institute of Nuclear Medicine and Oncology Lahore (INMOL), Lahore, from May 2016 to March 2017.

METHODOLOGY

All histopathologically proven cases of paranasal sinuses and nasal cavity were selected from the hospital record for epidemiological analysis. Survival outcomes of patients with squamous cell histopathology were determined, which is commonly occurring type. Relevant information was obtained from patient record and telephone communication. The data were analysed using SPSS V.20.

RESULTS

Sinonasal malignancies are rare, making (n=81) 0.2% of all registered tumors; out of which, 46 (56.7%) had squamous cell histology. Median age was 50.0 years (IQR: 60.7-40.0) with male predominance (1.7:1). Most of patients presented at advanced stage, T3/ T4 in more than two-thirds of cases, and associated with nodal metastasis in 43.5% of squamous cell carcinoma. In patients with squamous cell histology, median disease-free survival was 19.00 months (SE: 1.65, 95% CI, 15.75 - 22.25), median overall survival remained 34.00 months (SE: 1.84, 95% CI, 30.00 - 38.00). Nodal status had significant effect (p<0.001) on survival. Radiotherapy had significant effect on improved survival (p=0.001) and distant metastasis remained negative prognostic factor (p=0.001). Disease stage was also significantly associated with overall survival (Log Rank 0.014). Tumour size, surgery, chemotherapy, and chemoradiotherapy were not significantly associated with survival. Cumulative survival at 1, 2, and 3 years was 87%, 48% and 29%, respectively.

CONCLUSION

Sinonasal malignancies are rare, advanced stage is common, and radiotherapy improves overall survival.

Radiochemical neutron activation analysis of trace impurities in high purity titanium and tungsten

Rapid radiochemical neutron activation analysis (RNAA) procedures were developed and employed to the determination of 36 trace impurities in high purity titanium and tungsten. Anion–exchange column chromatography procedures were developed for the sequential group chemical separation of various elements, which helped in reducing the spectral interferences and improving the sensitivity of the method. The procedure is simple and requires a very short time to separate the elements in three groups for radiometric assay. To determine very low contents of uranium and thorium, 239Np and 233Pa as activation products were separated using anion–exchange and coprecipitation methods. The impurity contents were found to be low; therefore, their deleterious effects would be negligible.

Fission neutron spectrum averaged cross sections of some threshold reactions on titanium: production feasibility of 45Ti in a nuclear reactor

Systematic studies on fission neutron spectrum averaged cross sections of some threshold reactions like (n, 2n), (n, p) and (n, α) on titanium were carried out using the activation technique in combination with radiochemical separations and high-resolution γ-ray spectroscopy. Special attention was paid to the formation 45Ti via the 46Ti(n, 2n)45Ti reaction since 45Ti labeled compounds are potentially important radiopharmaceuticals. At a fast flux neutron density of 7.5 × 1013 cm−2 s−1 and using 100% enriched 46Ti target, 8.58 MBq saturation activity of 45Ti per batch can be produced. Due to rather low activity and low specific activity the procedure is not feasible from medical application point of view.