PAG1 stimulates proliferation and metastasis of nasopharyngeal carcinoma through downregulating PTEN

OBJECTIVE

We aim to uncover the expression pattern and biological functions of PAG1 in the progression of nasopharyngeal carcinoma (NPC).

PATIENTS AND METHODS

PAG1 levels in 28 paired NPC tissues and paracancerous tissues were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Then, the potential influences of PAG1 on proliferative, migratory and invasive abilities of SUNE2 and CNE2 cells were assessed by cell counting kit-8 (CCK-8) and transwell assay, respectively. Next, the interaction between PAG1 and its direct target gene of phosphate and tension homology deleted on chromosome ten (PTEN) was verified by Dual-Luciferase reporter gene assay. At last, rescue experiments were conducted to uncover the role of PAG1/PTEN axis in the malignant progression of NPC.

RESULTS

PAG1 was highly expressed in NPC tissues and cell lines. Knockdown of PAG1 blocked NPC cells to proliferate, migrate, and invade. Dual-Luciferase reporter gene assay indicated the binding relationship between PAG1 and PTEN. In addition, both mRNA and protein levels of PTEN were negatively regulated by PAG1 in NPC cells. Notably, PTEN was responsible for PAG1-regulated malignant progression of NPC.

CONCLUSIONS

PAG1 is upregulated in NPC tissues and cells and stimulates the proliferative and metastatic abilities in NPC by targeting PTEN, thus aggravating the malignant progression of NPC.

MiR-507 inhibits the growth and invasion of trophoblasts by targeting CAMK4

OBJECTIVE

To elucidate the potential influences of miR-507 and CAMK4 on the progression of preeclampsia (PE).

PATIENTS AND METHODS

Placental tissues were collected from 24 PE pregnancies and 24 healthy pregnancies. The relative levels of miR-507 and CAMK4 in placental tissues were detected. In addition, expressions of apoptosis-associated genes in collected tissues were examined by both quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA). The influences of miR-507 and CAMK4 on proliferative and migratory abilities in HTR-8/SVneo cells were assessed by CCK-8 and transwell assay, respectively. The target relationship between miR-507 and CAMK4 was detected by Luciferase assay.

RESULTS

MiR-507 was upregulated in placental tissues collected from PE pregnancies. Overexpression of miR-507 suppressed proliferative and migratory abilities, and stimulated apoptosis in HTR-8/SVneo cells. CAMK4 was the target gene of miR-507, which was downregulated in placental tissues collected from PE pregnancies and negatively correlated to miR-507 level. The knockdown of CAMK4 suppressed proliferative and migratory abilities, and stimulated apoptosis in HTR-8/SVneo cells, and these trends were abolished by silence of miR-507.

CONCLUSIONS

Highly expressed miR-507 in PE pregnancies inhibits proliferative and migratory potentials, and induces apoptosis in trophoblasts by targeting CAMK4.

[Advances in research of protein kinase A in parasites: a review]

Protein kinase A (PKA) is an important intracellular substance that regulates substance metabolism and biological functions, which exerts a wide range of biological effects through phosphorylation of specific serine/threonine residues in specific proteins. PKA plays an important role in the cAMP signaling pathway, and is involved in various life activities of parasites. Therefore, investigating the role of PKA in the life activities of parasites may provide insights into the development of novel anti-parasitic targets. The review mainly describes the structure and function of PKA and its role in life activities of parasites.

Inhibition effect of exosomes-mediated Let-7a on the development and metastasis of triple negative breast cancer by down-regulating the expression of c-Myc

OBJECTIVE

Triple negative breast cancer is typically characterized by high malignancy, easy recurrence and metastasis, and poor prognosis. However, effective treatment for triple negative breast cancer has not yet been identified. Our research explores the underlying mechanisms of exosomes in transporting Let-7a and regulating c-Myc gene and their roles in the development of triple negative breast cancer, and to provide new ideas for targeted therapy of triple negative breast cancer.

PATIENTS AND METHODS

Based on previous studies that focused on the roles of c-Myc and Let-7a in the development of triple negative breast cancer, triple negative breast cancer cell lines have been constructed by c-Myc knockout and overexpression of Let-7a, respectively, to evaluate the effects of c-Myc, and Let-7a, as well as exosomes transmitting Let-7a on the development of triple negative breast cancer.

RESULTS

Let-7a, which is mediated by exosomes, inhibited proliferation, migration, and invasion of MDA-MB-231 cells by binding on the 3'UTR region of the c-Myc gene and silencing of the c-Myc expression.

CONCLUSIONS

Our study revealed the role of c-Myc, Let-7a, and exosomes in the development of triple negative breast cancer, which lay the theoretical foundation for further usage of exosomes to construct tumor killing vectors and for exploring specific targets for triple negative breast cancer.

[Effect of overexpression of integrin β2 on clinical prognosis in triple negative breast cancer]

Objective: To investigate the clinical significance of the expression of integrin β2 (ITGB2) and tumor infiltrating dendritic cells CD80 and CD86 in triple negative breast cancer (TNBC). Methods: The expression levels of ITGB2 and MHC-1 in MDA-MB-231 cells and TNBC tissues were detected by Western bolt and RT-PCR, and the expressions of ITGB2, CD80 and CD86 in TNBC tissues were detected by immunohistochemistry. Results: 1.The expression level of ITGB2 in TNBC cell line (1.67±0.38) was higher than that in MCF-10A cell line (1.06±0.38), and the expression level of MHC-1 molecules in TNBC cell line (0.64±0.20) was lower than that in MCF-10A cell line (1.02±0.21). The difference was statistically significant (P=0.036 and 0.020, respectively). 2.The expression level of ITGB2 in TNBC tissues (1.55±0.47) was significantly higher than that in normal breast tissues (1.04±0.31). 3. Immunohistochemistry showed that the expression level of ITGB2 in TNBC tissues (3.31±2.29) was significantly higher than that in paracancerous tissues (1.20±1.19). Combined with clinicopathological data, it was suggested that the expression of ITGB2 was correlated with tumor stage (P=0.038), histological grade (P=0.022), lymph node metastasis (P=0.019), ki67 expression (P=0.000) and total survival (P=0.003). 4. Immunohistochemistry showed that the expression of CD80 and CD86 in TNBC tissues (3.07±1.57, 3.93±1.64) was significantly lower than those in paracancerous tissues (4.63±2.92 vs 5.23±2.85) (P=0.032 and 0.027). Conclusion: The high expression of ITGB2 in triple negative breast cancer affects the prognosis of patients.

[Effect of high expression of type Ⅰ collagen α1 chain protein on the prognosis of triple negative breast cancer]

Objective: To investigate the expression of type Ⅰ collagen α1 chain protein (COL1A1) in triple negative breast cancer (TNBC), and its relationship with clinicopathological features and prognosis of TNBC. Methods: A total of 148 TNBC specimens were collected from the Affiliated Cancer Hospital of Xinjiang Medical University from 2013 to 2015. The mRNA expression of COL1A1 was detected by fluorescence quantitative RT-PCR and the protein expression of COL1A1 was detected by Western blot. The expression of COL1A1 and α-smooth muscle actin (α-SMA) in TNBC were detected by immunohistochemistry. The relationship between the expression of COL1A1 and clinicopathological parameters and prognosis of TNBC patients was analyzed. Results: The mRNA and protein expression of COL1A1 in MDA-MB-231 cells were 1.696±0.486 and 0.550±0.088, respectively, which were higher than those in MCF-10A cells (1.020±0.231 and 0.350±0.083, P=0.032, P=0.046). The mRNA and protein expression of COL1A1 in TNBC tissues were 1.632 ±0.598 and 0.733 ±0.068, respectively, which were higher than those in paracancerous tissues (1.041±0.316 and 0.612±0.016, P=0.003, P=0.039). The high expression rates of COL1A1 and α-SMA in TNBC tissues were 35.8% and 56.7% respectively, which were higher than those in paracancerous tissues (16.7% and 30.0%, P=0.041, P=0.037). The expression of COL1A1 was correlated with tumor size, TNM stage, lymph node metastasis, vascular invasion and α-SMA expression (all P<0.05). The median survival time in COL1A1 high expression group was 64 months, which was lower than that in low expression group (73 months, P<0.05). Multivariate analysis of Cox proportional hazard regression model showed that COL1A1 expression was an independent influencing factor for the survival of TNBC patients (HR=3.952, P=0.004). Conclusion: The high expression of COL1A1 in TNBC is an independent prognostic factor of TNBC patients.

Pyruvate kinase genes in grass carp Ctenopharyngodon idella: molecular characterization, expression patterns, and effects of dietary carbohydrate levels

To explore features of carbohydrate metabolism and evolution of carbohydrate metabolism-associated genes in herbivorous fishes, the open reading frames (ORF) of PKL, PKMa, and PKMb genes of grass carp (Ctenopharyngodon idella) were obtained, encoding 538, 528, and 532 amino acids, respectively. Comparative genomic analysis showed that adjacent PK genes were highly conserved between fish and mammals. Gene expression profiles were quite different between the three PK genes in tissues and at developmental stages. PKL, PKMa, and PKMb had the highest expression levels in the liver, heart, and muscle, respectively. During embryogenesis, high expression levels of PKMa and PKMb were detected in unfertilized and fertilized eggs. Following a non-expression period, PKMa and PKMb exhibited high expressions again after the hatching stage. In contrast, PKL transcripts could not be detected in early developmental stages, and expression levels continued to increase from the hatching stage to 144 h post hatching. After the 8-week feeding trial with 18%, 30%, and 42% dietary carbohydrate levels, the concentrations of glucose and insulin in serum, pyruvate kinase enzymes, and gene expression levels in brain, muscle, and liver tissues all increased with the increase in carbohydrate levels in the diets. Furthermore, high carbohydrate levels (30% and 42% carbohydrate diets) had a greater effect on grass carp growth. This indicated that PKL, PKMa, and PKMb genes were not only very important in catalytic enzymes, which can be up-regulated by high carbohydrate dietary conditions, but also exhibited a complex and detailed division of labor in different tissues and developmental stages.

[Association between the time of sedentary behaviors and risk of type 2 diabetes]

Objective: To explore the relationship between the time of sedentary behaviors and the risk of type 2 diabetes mellitus (T2DM) among rural adults in Henan Province. Methods: A total of 1 227 adults from Houzhai village in Zhengzhou City and Qiaomiao village in Jiaozuo City in Henan Province were randomly selected to participate in the survey; each of them finished a questionnaire and accepted physical examination and test of biochemical indicators. The participants were divided into case and control groups according to whether suffering from T2DM. A Pearson linear correlation and linear regression model analysis were used to investigate the relevance between the time of sedentary behaviors and fasting plasma glucose (FPG); meanwhile, a multi factor logistic regression model was used to analyze the relationship between the time of sedentary behaviors and T2DM. Results: The average FPG level among the participants was (5.4±2.5) mmol/L, and the average time of sedentary behaviors was (234.5±156.5) min per day. The prevalence rate of T2DM in subgroups whose time of sedentary behaviors were separately 0-<2.5, 2.5-<4.5, 4.5-<6.5 and ≥6.5 h/day were 15.8% (72/457), 19.3% (73/379), 16.7% (35/210) and 20.4% (37/181), respectively. There was a linear regression relationship between the time of sedentary behaviors(x) and FPG(y), the regression equation was: y=5.081+0.001x (t=3.01, P=0.003). Logistic regression model analysis showed that participants whose time of sedentary behaviors ≥6.5 h/day had significantly higher risk of T2DM than those whose time of sedentary behaviors between 0-2.4 h/day (OR=1.77, 95%CI: 1.11-2.81) after age and gender adjusted. However, the associations only exist in males and adults ≥50 years old according to sex and age stratification. It showed that participants with sedentary time ≥6.5 h/day had significantly higher risk of T2DM than those with sedentary time between 0-<2.5 h/d, with the corresponding OR (95%CI) at 2.34 (1.21-4.52) and 2.22 (1.19-4.16), respectively. Conclusion: The prolonged sedentary time is a risk factor of type 2 diabetes. After stratification by gender and age, the correlation only found in males and adults aged ≥50 years old.

Swimming intervention mitigates HFD-induced obesity of rats through PGC-1α-irisin pathway

OBJECTIVE

Irisin, a newly discovered myokine, can drive the browning of white adipocytes to control body weight or mitigate obesity progression through regulating energy metabolism. However, the underlying mechanisms or specific signal pathways of exercise-induced irisin on the management of obesity are still unclear.

MATERIALS AND METHODS

Totally 30 rats were subjected to high fat diet (HFD) feeding for 8 weeks to establish the rat model with obesity successfully. HFD-induced obese model rats were provided with 8 weeks swimming intervention at moderate intensity for exploring the treatment of obesity through exercise intervention. In addition, another 15 rats were subjected to HFD feeding coupled with total 16 weeks swimming intervention at a moderate intensity from the beginning of the experiment, which was used for exploring the prevention of obesity through exercise intervention. Blood and gastrocnemius samples were harvested from obese rats after swimming intervention to explore its specific signal pathways through ELISA analysis and Western blotting.

RESULTS

HFD feeding of rats for 8 weeks could lead to the obesity due to the disorders of lipid metabolism. Totally 8 weeks swimming intervention at moderate intensity for rats with obesity could obviously alleviate the progression of obesity and 16 weeks swimming intervention from the beginning of the experiment could significantly inhibit the development of obesity. Meanwhile, swimming intervention could result in an increased phosphorylation of AMPK and up-regulation of irisin and PGC-1α as the biomarkers of energy metabolism.

CONCLUSION

Exercise intervention can activate PGC-1α-dependent irisin to induce the browning of white adipocytes, thus inhibiting or alleviating the occurrence and development of obesity.

A prospective evaluation of minimal residual disease as risk stratification for CCLG-ALL-2008 treatment protocol in pediatric B precursor acute lymphoblastic leukemia

OBJECTIVE

The aim of this prospective study was to evaluate the cut-off value of minimal residual disease (MRD) in predicting the efficacy of CCLG-ALL-2008 or CCLG-2008 treatment protocol on pediatric B-precursor ALL (BP-ALL).

PATIENTS AND METHODS

Three hundred and seventy-nine Chinese pediatric BP-ALL were enrolled in this study between Dec 2008 and Sep 2013 in two stratified cohorts. One hundred and fifty-three patients enrolled between Dec 2008 and Oct 2010 as the first cohort, and 196 patients enrolled from Nov 2010 to Sep 2013 as the second cohort. Clinical and biological characteristics and 5 years EFS, RFS, and OS were analyzed.

RESULTS

Patients with E2A-PBX1 showed a favorable treatment response with a lower minimal residual disease (MRD) level (< 10-4) at the time point 1 (TP1, p = 0.039) and the highest proportion of the 5-year EFS, RFS, and OS. A high level of MRD was associated with high WBC counts, increased age, BCR-ABL1 fusion gene, MLL rearrangements and adverse karyotypes. In comparison with the first cohort, the second cohort with the MRD assay incorporated prospectively, the standard risk (SR) and the intermediate risk (IR) patients showed a better RFS, EFS, and OS while the high-risk (HR) patients displayed worse RFS, EFS, and OS than those of the first cohort, respectively. Patients with MRD level at either 10-4 or 10-3 showed a similar OS at TP1 or TP2, and patients with MRD level above 10-2 had the worst OS.

CONCLUSIONS

This study indicated that the levels of MRD to be an adequate guide in risk-adapted treatment under the CCLG-ALL-2008 protocol and can be adapted to the future development of advanced clinical protocols.

A rat model designed for the continuous intraarterial infusion of cyclosporine

BACKGROUND

Limb allotransplantation is not a life-saving treatment. However, large doses of immunosuppressive agents are needed. There is an urgent need to increase the selectivity and targeting of drugs.

METHODS

We designed a rat model for intraarterial infusion of cyclosporine (CSA) based on the hindlimb replanted model to simulate the limb allotransplantation. To investigate whether intraartery infusion could improve the drug's distribution, we infused CSA 4.0 mg/kg per day continuously into either the superficial epigastric artery (IA group) or superficial epigastric vein (IV group) of Lewis rats.

RESULTS

On day 10, CSA concentrations were measured in skin, muscle, and bone tissues of hindlimb. Samples were taken from different parts of the bilateral hindlimbs in the IA group and right hindlimb only in the IV group. Tissue concentrations of the perfusion side were much higher in IA group. Systemic concentrations of IA group were higher than IV group.

CONCLUSIONS

These results warrant further research in our next limb allotransplantation model.

Characterization of a TIR-NBS-LRR gene associated with downy mildew resistance in grape

Grapevine downy mildew, caused by Plasmopara viticola, is a devastating disease that results in considerable economic losses as well as environmental damage through the repeated application of fungicides. The nucleotide-binding site leucine-rich repeat gene family functions in plant immunoactivity against various pathogens and pests. In this study, the 5' and 3' ends of the resistance gene homology fragment RGA5 were obtained by rapid amplification of cDNA ends. The 4282-base pair full-length cDNA was obtained using gene-specific primers, and the corresponding 1335-amino acid protein sequence contained characteristic nucleotide-binding site leucine-rich repeat domains of plant resistance proteins, including the toll-interleukin receptor type region. Expression of RGA5 during P. viticola infection and abiotic stress was investigated using quantitative real-time polymerase chain reaction. The results showed that treatment with P. viticola and 4 abiotic stimuli (salicyclic acid, methyl-jasmonate, abscisic acid, H2O2) significantly induced RGA5 within 12 days of inoculation. Therefore, RGA5 may play a critical role in protecting grapevines against P. viticola via signaling pathways involving these molecules.

Isolation and characterization of a Vibrio vulnificus mutant deficient in both extracellular metalloprotease and cytolysin

We isolated a Vibrio vulnificus mutant that was deficient in both metalloprotease and cytolysin by allelic exchange. The virulence of this mutant in mice and its cytotoxicity for HEp-2 cells were comparable to those of the wild-type strain, indicating that neither factor was essential for these properties. The cytolysin, but not the protease, seemed to be important for causing damage in the alimentary tract of the mice.

Differences in gene expression in muscle-invasive bladder cancer: a comparison of Italian and American patients

OBJECTIVE

To seek differences in gene expression in the primary muscle-invasive bladder cancers of two cohorts of patients having different survival rates. An Italian group treated by transurethral resection of the bladder tumor (TURBT) and neo-adjuvant chemotherapy using methotrexate, vinblastine, adriamycin and cisplatin (M-VAC) followed by TURBT, partial cystectomy or radical cystectomy (75% 3-year survival) was compared to an American cohort treated by radical cystectomy (51% 3-year survival).

METHODS

Immunohistochemistry was used to examine the protein expression levels of three genes that act at the G1/S cell cycle checkpoint, p53, p21/waf-1/cip1 (a downstream effector gene in the p53 pathway) and Rb, plus a major inhibitor of apoptosis, Bcl-2.

RESULTS

For the bladder cancers of the Italian patient cohort, there was a significantly higher rate of p53 immunopositivity (93 vs. 63%, p = 0.002) and a significantly lower rate of Rb loss (25 vs. 54%, p = 0.009). In bivariate analysis, 72% of Italian tumors were immunopositive for both p53 and p21 (p53+/p21+) vs. 49% for the American tumors. The subset of Italian patients with p53+/p21+ tumors were more frequently disease-free (stage pT0) following chemotherapy and were less likely to fail therapy than those with p53+/p21- tumors (p = 0.0357). Loss of Rb staining was associated with a decreased 5-year survival in the Italian, but not in the American patients.

CONCLUSIONS

(1) Significant differences in the expression of the p53, p21 and Rb genes were found between the 2 groups of patients. (2) Italian patients with p53+/p21+ tumors had significantly lower recurrence rates after TURBT and chemotherapy than those having p53+/p21- tumors. (3) Absence of p21 immunopositivity in the Italian tumors may identify alterations in the p53 pathway that predict poor outcome.

Experimental measurements of dosimetric parameters on the transverse axis of a new 125I source

Permanent prostate implant using 125I or 103Pd sources is a common treatment choice in the management of early prostate cancer. As sources of new designs are developed and marketed for application in permanent prostate implants, it is of paramount importance that their dosimetric characteristics are carefully determined, in order to maintain a high accuracy of patient treatment. This report presents the results of experimental measurements of the dosimetric parameters performed for a newly available 125I seed source, the model MED3631-A/M source (IoGold), manufactured by North American Scientific, Inc. The measurements were performed in a large scanning water phantom, using a diode detector. The positioning of the source and the diode detector was achieved by a computer-controlled positioning mechanism in the scanning water phantom. The dose rate constant in water for the new 125I source was measured in comparison with an existing 125I source of similar design and verified using thermoluminescent dosimetry (TLD) measurement. The radial dose function values for the source were measured using the diode detector. The measurement technique and the results are compared with the dose distribution parameters for the 125I sources discussed in the AAPM TG43 report and elsewhere [Med. Phys. 26, 570-573 (1999)]. For the dose rate constant in water of the new source, it is recommended that a value of 0.950 cGy/U-hr be used based on the NIST 1985 air-kerma strength calibration standard, or 1.060 cGy/U-hr based on the 1999 NIST air-kerma strength standard. The measured radial dose function values for the MED3631-A/M source agree closely with those of the model 6702 source. It is therefore recommended that the radial dose function values for the model 6702 125I source, as recommended by the AAPM TG43 report, be adopted for the new source as well.

Monte Carlo calculations and experimental measurements of dosimetry parameters of a new 103Pd source

Permanent prostate implantation using 125I (iodine) or 103Pd (palladium) sources is a popular treatment option in the management of early prostate cancer. As sources of new designs are developed and marketed for application in permanent prostate implantations, their dosimetric characteristics must be carefully determined in order to maintain the accuracy of patient treatment. This report presents the results of experimental measurements and Monte Carlo calculations of the dosimetric parameters performed for a newly available 103Pd seed source. The measurements were performed in a large scanning water phantom using a diode detector. The positioning of the source and detector was achieved by a computer-controlled positioning mechanism in the scanning water phantom. The dose rate constant in water for the new 103Pd source was determined from measurements with the diode detector calibrated with 125I sources of known air-kerma strength. The radial dose function values for the source were measured using the diode detector. Monte Carlo photon transport calculations were then used to calculate the dosimetric parameters of dose rate constant, radial dose function, and anisotropy function using an accurate geometric model of the source. The measured dose rate constant of 0.693 cGy/U-hr compares well with the Monte Carlo calculated value of 0.677 cGy/U-hr. These results are further compared with data on existing 103Pd sources.

Dosimetric characterization of a new design 103 palladium brachytherapy source

Low-energy gamma emitting isotopes encapsulated for permanent implant are in routine use in the treatment of prostate cancer. New source designs require full dosimetric analysis and calibration standardization before responsible clinical application. The results of one such experimental measurement and analysis are here reported for a new design of 103palladium source, model MED3633 (North American Scientific, Inc.). By AAMP Task Group #43 recommendations, the reference material for brachytherapy dosimetry is liquid water. The dose measurements were made using standard methods employing thermoluminescent dosimeters in a water equivalent plastic phantom. Precision machined bores in the phantom located dosimeters and source(s) in a reproducible fixed geometry providing for transverse-axis and angular dose profiles over a range of distances from 0.17 to 7 cm. The data were analyzed in terms of parameters recommended by AAPM TG43. The dose-rate constant, lambda, was evaluated with reference to a 60 cobalt standard, accounting for response variation with isotope energy spectrum. The radial dose function, g(r), the anisotropy function, F(r, theta), the anisotropy factor, phi,un(r), and the point-source approximation anisotropy constant, phi(un), were derived from one- and two-dimensional dose distribution data measured in the phantom, accounting for finite dosimeter volume and with attention to interchip effects. The results are compared to TG43 and other existing data for 103Pd sources. The new source is comparable to the model 200 103Pd source design, demonstrating equivalent radial dose function, g(r). The dose surrounding a MED3633 source may be slightly more isotropic than for the model 200 source. The air-kerma strength of the MED3633 source used in this study was provided by the manufacturer and is traceable to the NIST 1999 standard. The evaluated dose-rate constant, lambda, with NIST traceable strength calibration is lower than that of the model 200 source, with that manufacturer's strength calibration.

Report on the dosimetry of a new design 125Iodine brachytherapy source

Dosimetric measurements were performed to characterize a new 125I source that is a variant design of an existing source, designated as MED3631-A/S, and that has application in interstitial brachytherapy. The new source, designated as MED3631-A/M, has centralized radio-opaque markers. In the original MED3631-A/S source, the radio-opaque markers are separated. Thermoluminescent dosimeters were placed in phantom to measure transverse axis and angular dose profiles over a range of distances from 0.5 to 7 cm. The data were analyzed in terms of parameters recommended by AAPM Task Group No. 43. Tabular data evaluated in liquid water are provided for the dose-rate constant, lambda, radial dose function, g(r), the anisotropy function, F(r,theta), the anisotropy factor, phi(an)(r), the point-source approximation anisotropy constant, phi(an). The dose-rate constant was determined by an absolute method using a Cobalt-60 reference and by relative measurements using calibrated 125I source(s). Values of the dose-rate constant are provided for both the 1985 and 1999 NIST air-kerma strength standards. The new source is comparable to both the MED3631-A/S and the model 6702 125I source designs, demonstrating equivalent radial dose function, g(r). Differences in the value of the dose-rate constant, lambda, and the anisotropy of the dose distributions in phantom are discussed in light of the improved isotropy of the new design, the MED3631-A/M source, and the uncertainty involved in the dose measurement using a Cobalt-60 reference.

Inhibition of aflatoxin-producing fungi by Welsh onion extracts

Welsh onion ethanol extracts were tested for their inhibitory activity against the growth and aflatoxin production of Aspergillus flavus and A. parasiticus. The survival of spores of A. flavus and A. parasiticus depended on both the extract concentration and the exposure time of the spores to the Welsh onion extracts. The mycelial growth of two tested fungi cultured on yeast extract-sucrose broth was completely inhibited in the presence of the Welsh onion ethanol extract at a concentration of 10 mg/ml during 30 days of incubation at 25 degrees C. The extracts added to the cultures also inhibited aflatoxin production at a concentration of 10 mg/ml or permitted only a small amount of aflatoxin production with extract concentration of 5 mg/ml after 2 weeks of incubation. Welsh onion ethanol extracts showed more pronounced inhibitory effects against the two tested aflatoxin-producing fungi than did the same added levels of the preservatives sorbate and propionate at pH values near 6.5.

Evaluation of a new brachytherapy iodine-125 source by AAPM TG43 formalism

Dosimetric measurements were performed to characterize a new 125I source that is similar in design to existing sources and that has application in interstitial brachytherapy. Thermoluminescent dosimeters were placed in phantom to measure transverse-axis and angular dose profiles over a range of distances from 0.5 to 7 cm. The data were analyzed in terms of parameters recommended by AAPM Task Group #43. Tabular data evaluated in liquid water are provided for the dose-rate constant, lambda, radial dose function, g(r), the anisotropy function, F(r, theta), the anisotropy factor, phi an(r), the point-source approximation anisotropy constant, phi an, and the point-source average dose rate times the square of distance for unit air kerma strength, r2D(r). The new source is compared to the model 6702 125I source design, demonstrating similar dose-rate constant, lambda, and radial dose function, g(r). Differences in the anisotropy of the dose distributions are discussed. Finally, a comparison of the radial dose distribution is made between liquid water and tissue equivalent materials.

Cross-sectional assessment of renal function in the inhabitants of a cadmium-polluted area

To understand the development of cadmium (Cd)-induced renal tubular dysfunction, cross-sectional assessment of renal function in the inhabitants of the Cd-polluted Jinzu River basin in Toyama, Japan, was carried out. Sixty-seven men and 78 women, aged 56 to 71 years whose urinary beta 2-microglobulin (beta 2-m) exceeded 1,000 micrograms/g creatinine, were examined and divided into five groups according to their values of fractional excretion of beta 2-m (FE beta 2-m). Comparisons were made between six groups including the inhabitants of a non-polluted area as a reference group. Significantly increased values of fractional excretion of urate (FEUA), calcium (FECa), sodium (FENa), and chloride (FECl), serum creatinine and beta 2-m, and urinary protein were detected even in the subjects with FE beta 2-m level below 1 percent compared with the reference group. Fractional phosphate reabsorption (percent TRP) was significantly decreased in the subjects with FE beta 2-m level above 10 percent. Creatinine clearance (CCr) decreased with increase in FE beta 2-m, and the subjects with FE beta 2-m above 30 percent showed significantly decreased CCr values compared to those with FE beta 2-m below 30 percent. In summary, FEUA, FECa, FENa, and FECl, as well as low-molecular-weight proteins such as beta 2-m, are increased in the early stage of Cd-induced renal tubular dysfunction. Although percent TRP was maintained by the decreased CCr, there was a marked decrease in percent TRP in subjects with progressive stage showing FE beta 2-m level above 10 percent. No sex difference in renal tubular dysfunction was found in this cross-sectional study.