Assessment of exposure to heavy metals and health risks among residents near abandoned metal mines in Goseong, Korea

Metal contamination from mining activity is of great concern because of potential health risks to the local inhabitants. In the present study, we investigated the levels of Cd, Cu, As, Pb, and Zn in environmental samples and foodstuffs grown in the vicinity of the mines in Goseong, Korea, and evaluated potential health risks among local residents. Soils near the mines exceeded the soil quality standard values of Cu, As, and Zn contamination. The concentrations of Cd, Cu, Pb, and Zn in crop samples collected from the study area were significantly higher than those of the reference area. Some rice samples collected from the study area exceeded the maximum permissible level of 0.2 mg Cd/kg. The intake of rice was identified as a major contributor (≥75%) to the estimated daily intake among the residents. The average estimated daily intakes of metals were, however, below the provisional tolerable daily intake.

Construction of a primary DNA fingerprint database for cotton cultivars

Forty core primers were used to construct a DNA fingerprint database of 132 cotton species based on multiplex fluorescence detection technology. A high first successful ratio of 99.04% was demonstrated with tetraplex polymerase chain reaction. Forty primer pairs amplified a total of 262 genotypes among 132 species, with an average of 6.55 per primer and values of polymorphism information content varying from 0.340 to 0.882. Conflicting DNA homozygous ratios were found in various species. The highest DNA homozygous ratio was found in landrace standard cultivars, which had an 81.46% DNA homozygous ratio. The lowest occurred in a group of 2010 leading cultivars with a homozygous ratio of 63.04%. Genetic diversity of the 132 species was briefly analyzed using unweighted pair-group method with arithmetic means.

Different combinations of probiotics improve the production performance, egg quality, and immune response of layer hens

To evaluate the effects of different combinations of probiotics on performance, egg quality, and immune response of layer hens, a trial was carried out with 1,800 white feather layer hens of the Lohmann variety. The experiment was conducted by using a completely randomized design with 9 treatments, 4 replicates, and 50 hens in each replicate. Compared with the control group, group F, which added a composition of heat-inactivated Lactobacillus salivarius(CB) and Bacillus subtilis to the diets of layer hens, caused highly significant (P < 0.05) increases in egg production, daily egg yield, damaged egg ratio, combined with a significant (P < 0.05) decrease in feed conversion and damaged egg ratio. Group G, adding a combination of inactivated Lactobacillus salivarius and sodium butyrate, resulted in a significant increase (P < 0.05) in daily egg yield, feed conversion, damaged egg ratio and Haugh unit. Meanwhile, groups D and H had significantly decreased feed conversion (P < 0.05), and groups B, H, and I had a significantly decreased damaged egg ratio. In serum levels, no significant difference was observed except a significant decrease (P < 0.05) in total cholesterol (groups D, E, and G) and low-density lipoprotein cholesterol (group E and G) and a significant increase (P < 0.05) in total cholesterol (groups D, E, and G) compared with group A. According to the hemagglutination inhibition test, the antibody titer of antibody against the avian influenza virus was significantly (P < 0.05) higher in most treated groups such as groups B, C, E, G, and I after d 15 fed to layers with probiotics and groups B, C, D, E, F, G, and H after d 45 compared with the control group. No significant difference was observed in the antibody titer against the Newcastle disease virus at d 15, but significantly (P < 0.05) higher at d 45 in groups F and G. These results demonstrate that several combinations of probiotics used in this experiment have a positive impact on the performance, egg quality, and immune response of layer hens, and the following work will continue to focus on these groups.

C1 esterase inhibitor concentrate in 1085 Hereditary Angioedema attacks--final results of the I.M.P.A.C.T.2 study

BACKGROUND

The placebo-controlled study International Multicentre Prospective Angioedema C1-INH Trial 1 (I.M.P.A.C.T.1) demonstrated that 20 U/kg C1 esterase inhibitor (C1-INH) concentrate (Berinert®; CSL Behring, Marburg, Germany) is effective in treating acute abdominal and facial Hereditary Angioedema (HAE) attacks.

METHODS

I.M.P.A.C.T.2 was an open-label extension study of I.M.P.A.C.T.1 to evaluate the safety and efficacy of long-term treatment with 20 U/kg C1-INH for successive HAE attacks at any body location. Efficacy outcomes included patient-reported time to onset of symptom relief (primary) and time to complete resolution of all symptoms (secondary), analysed on a per-patient and per-attack basis. Safety assessments included adverse events, vital signs, viral safety and anti-C1-INH antibodies.

RESULTS

During a median study duration of 24 months, 1085 attacks were treated in 57 patients (10-53 years of age). In the per-patient analysis, the median time to onset of symptom relief was 0.46 h and was similar for all types of attacks (0.39-0.48 h); the median time to complete resolution of symptoms was 15.5 h (shortest for laryngeal attacks: 5.8 h; 12.8-26.6 h for abdominal, peripheral and facial attacks). Demographic factors, type of HAE, intensity of attacks, time to treatment, use of androgens and presence of anti-C1-INH antibodies had no clinically relevant effect on the efficacy outcomes. There were no treatment-related safety concerns. No inhibitory anti-C1-INH antibodies were detected in any patient.

CONCLUSIONS

A single dose of 20 U/kg C1-INH concentrate is safe and provides reliable efficacy in the long-term treatment of successive HAE attacks at any body location.

Exploring the binding features of polybrominated diphenyl ethers as estrogen receptor antagonists: docking studies

The polybrominated diphenyl ethers (PBDEs) accumulating in nature are known to be endocrine-disrupting compounds. Of first concern are those interacting with and altering activity of the human estrogen receptor alpha (hERalpha). In this study a docking study was carried out to explore the binding modes of PBDE compounds as hERalpha antagonists. It was found that some of the PBDE compounds with antiestrogenic activity extended into the channel of the estrogen receptor (ER), which is usually occupied by the alkylamine side chain of the ER antagonists raloxifene (RAL) and 4-hydroxytamoxifen (OHT), while most PBDE compounds without antiestrogenic activity adopted binding modes similar to that of ER agonist 17beta-estradiol (E2), located in the binding cavity and which did not protrude into the channel. The present study suggests that pose comparison based on docking is useful for discriminating whether or not PBDE compounds have antiestrogenic activity. Knowing the binding modes of compounds in hERalpha can help to screen out antiestrogenic compounds and further develop descriptive and predictive models in ecotoxicology.

Investigation on health effects of an abandoned metal mine

To investigate potential health risks associated with exposure to metals from an abandoned metal mine, the authors studied people living near an abandoned mine (n=102) and control groups (n=149). Levels of cadmium, copper, arsenic, lead, and zinc were measured in the air, soil, drinking water, and agricultural products. To assess individual exposure, biomarkers of each metal in blood and urine were measured. beta2-microglobulin, alpha1-microglobulin, and N-acetyl-beta-glucosaminidase and bone mineral density were measured. Surface soil in the study area showed 2-10 times higher levels of metals compared to that of the control area. Metal concentrations in the groundwater and air did not show any notable differences between groups. Mean concentrations of cadmium and copper in rice and barley from the study area were significantly higher than those of the control area (p<0.05). Geometric means of blood and urine cadmium in the study area were 2.9 microg/L and 1.5 microg/g Cr, respectively, significantly higher than those in the control area (p<0.05). There were no differences in the levels of urinary markers of early kidney dysfunction and bone mineral density. The authors conclude that the residents near the abandoned mine were exposed to higher levels of metals through various routes.

Inhibition of 12-lipoxygenase during baicalein-induced human lung nonsmall carcinoma H460 cell apoptosis

Baicalein is known as a 12-lipoxygenase (12-LOX) inhibitor. The 12-LOX is found to be involved in the progression of human cancers and the inhibitor of 12-LOX offers a target for the prevention cancer. We demonstrated the inhibitory effect of baicalein on the gene and protein expression of 12-LOX in H460 human lung nonsmall carcinoma cell line. Treatment of baicalein inhibited the growth of H460 cells in a dose-dependent manner. Following 24h exposure to 50muM baicalein, cell cycle analysis revealed an increase in the cell population in S-phase. During the S-phase arrest, baicalein decreased the protein levels of cdk1 and cyclin B1, which are the regulating proteins of S-phase transition to G2/M-phase, in this study. Furthermore, baicalein induced the most of H460 cell apoptosis after treatment for 48h. H460 cells formed vesicles and apoptotic body, and then floated after treatment with baicalein. Baicalein-induced H460 cell apoptosis was confirmed by DNA condensation and fragmentation. Baicalein-induced apoptosis were also accompanied by decreasing in Bcl-2 and proform of caspase-3 and increasing p53 and Bax protein levels. Pretreatment with a specific caspase-3 inhibitor, Ac-DEVD-CHO, partially reduced baicalein-induced cell death, indicating baicalein induces apoptosis is partially dependent on caspase-3 pathway in H460 cells. These data suggest that baicalein, a 12-LOX inhibitor, inhibits the proliferation of H460 cells via S-phase arrest and induces apoptosis in association with the regulation of molecules in the cell cycle and apoptosis-related proteins.

In vitro study of ultrasound based real-time tracking for renal stones in shock wave lithotripsy: Part II--a simulated animal experiment

PURPOSE

We have previously developed and reported an ultrasound based real-time tracking system for renal stones. In the current study we continued to verify the reliability of this tracking system by a simulated animal test.

MATERIALS AND METHODS

We used 13 prerecorded ultrasound stone trajectories to test the system. The real-time tracking system was implemented on the Litemed 9200 electrohydraulic lithotriptor (LiteMed Co., Taipei, Taiwan). An artificial stone and tap water were sealed in a balloon. The balloon was inserted into the pelvis of a pig kidney. While the kidney was affixed to and moved by a simulator, it was immersed in a specifically designed simulated animal model tank containing tap water. The stone was localized by ultrasound. The kidney was moved by the simulator according to a prerecorded stone trajectory. A total of 3,000 shock waves were delivered to the stone. For each recorded stone trajectory experiments were done under nontracking and tracking conditions. We performed tests of the fragment-to-weight ratio, which denotes the performance of a shock wave lithotriptor when fragmenting a stone.

RESULTS

The mean fragment-to-weight ratio was 55.3% +/- 25.9% in the nontracking and 100% +/- 0% in the tracking group. The difference in these 2 groups was statistically significant (paired t test p <0.01).

CONCLUSIONS

The ultrasound based real-time tracking system proved to improve the performance of a shock wave lithotriptor significantly when fragmenting stones in a simulated animal test. We believe that the tracking system would greatly reduce the number of shocks and time needed for treating renal stones.

Extravesical cryosurgical approach for VX2 bladder tumor in rabbits

This study characterized the VX2 bladder cancer model in rabbits and tested the feasibility of treating bladder cancer by extravesical cryosurgery. After the growth characteristics of the VX2 bladder tumor model were determined, the VX2 tumor was inoculated into rabbits at the dome of the bladder. One week later, three freeze/thaw cycles were followed by immediate surgical repair. The control group underwent a sham operation without freezing. When the VX2 tumor is injected into the bladder wall, invasion and central necrosis occurred within I week, lymphatic metastases by 2 weeks, and lung metastases by 3 weeks after inoculation. By 4 weeks, all control rabbits had large VX2 tumors in their bladders and advanced lung metastases. Nine of the ten rabbits in the cryosurgical group had mild to moderate degrees of lung metastases, and six of them had relatively small local recurrences. One rabbit had no tumor in the bladder and only microscopic lung metastasis. The extravesical approach to cryosurgery employing bladder inversion is well tolerated. Cryosurgery exhibits modest efficacy in treating local tumors and delaying lung metastasis in this aggressive tumor model.

Food-dependent exercise-induced anaphylaxis

Food-dependent exercise-induced anaphylaxis (FDEIA) is a specific variant of exercise-induced anaphylaxis that requires both vigorous physical activity and the ingestion of specific foods within the preceding several hours. When patients present to the emergency department (ED) with allergic reactions, careful history regarding these 2 factors is required to establish the correct diagnosis. Correct diagnosis of FDEIA will allow patients to take control of their lifestyles and avert repeated events and ED visits. Two cases of FDEIA are presented, and the diagnosis, pathophysiology and therapy of food-dependent exercise-induced anaphylaxis are reviewed.

Transurethral microwave thermotherapy for symptomatic benign prostatic hyperplasia: long-term durability with Prostcare

OBJECTIVE

To evaluate the long-term durability of transurethral microwave thermotherapy (TUMT) with Prostcare for symptomatic benign prostatic hyperplasia (BPH).

PATIENTS AND METHODS

From August 1993 to July 1994, a total of 65 patients with symptomatic BPH who underwent TUMT using the Prostcare apparatus (Bruker Spectospin, Wissembourg, France) with low-energy protocol (maximal power 52 W) were enrolled into a short-term evaluation. Subsequent follow-up information was collected in July 1999. If patients had had any further therapy for BPH, the date of retreatment was considered as an endpoint of TUMT efficacy. If no further therapy for BPH had been needed, they were re-assessed for overall satisfaction.

RESULTS

The median follow-up period was 49 months. Twenty patients were excluded for various reasons, including 17 with loss of follow-up and 3 with new diseases that could affect the voiding status. Thirty-eight (84.4%) of 45 valuable patients had received further therapy for BPH, including medication (n = 21, 46.7%), and endoscopic surgery (n = 17, 37.7%). The times to pharmacologic or endoscopic retreatment after TUMT were 8.9+/-11.1 and 23.0+/-14.4 months, respectively (p = 0.0003, log rank test). Only 7 (15.5%) patients had no further treatment, with 3 having satisfactory improvements, but 4 feel dissatisfied yet not needing any further therapy. In addition, 2 patients complained of erectile dysfunction after TUMT and 1 was diagnosed with prostate cancer 50 months after TUMT. In addition, there was no significant difference for all baseline values among three groups with no retreatment or retreatment with medication or endoscopic surgery.

CONCLUSION

At the 5-year follow-up, the long-term durability of low-energy TUMT with Prostcare is only exhibited in a few patients and the overall retreatment rate was 84.4%. Thus, patient should be informed of the high probability of supplementary treatment after TUMT.

Internalization rates of murine and ovine gonadotropin-releasing hormone receptors

Rates of internalization of the murine GnRH receptor fused via its C-terminus to green fluorescent protein (GnRH-R-GFP) were examined in Chinese hamster ovary cells (CHO cells) and compared to those of native murine GnRH-R in a clonal murine gonadotroph cell line (LbetaT2 cells). The resulting rates of internalization of murine receptors were then compared with those of sheep GnRH-R in ovine gonadotrophs. Cells were incubated with radioiodinated [D-Ala6]GnRH on ice for 4 h to allow binding of the ligand to GnRH-R, then cells were warmed to 37 degrees C to permit internalization. Surface-bound radioligand began to decrease as soon as the cells were warmed and had decreased significantly within 20 min. A steady-state level of surface-bound radioligand was achieved after 60 min in both CHO cells and LbetaT2 cells (38% and 41%, respectively, of initial value; P < 0.05). Internalization of radioligand began immediately after warming the cells to 37 degrees C, and a significant proportion of surface ligand had been internalized by 20 min. A steady-state maximum of internalization was reached after 60 min in both CHO cells and LbetaT2 cells (29% and 28%, respectively, of total cell-associated ligand; P < 0.05). Changes in surface-bound radioligand and internalized radioligand in sheep pituitary cells were similar to those in CHO cells and LbetaT2 cells, but the amount of radioligand internalized after 60 min (40% of total cell-associated ligand) was 1.4 times higher than in CHO cells and LbetaT2 cells (P < 0.05). In a separate experiment, the effect of estradiol on the rate of internalization of GnRH-R in ovine pituitary cells was examined. Although treatment of ovine pituitary cells with estradiol approximately doubled the number of GnRH receptors, it did not alter either the rate or extent of receptor internalization. These results show that rates of internalization of recombinant murine GnRH-R-GFP in CHO cells and native murine and ovine GnRH-R in LbetaT2 cells and in sheep pituitary cells, respectively, are similar, but amounts of ovine GnRH-R internalized are greater than those for murine GnRH-R. Further, the rate of internalization of occupied receptor is similar in gonadotroph and nongonadotroph cells, and the addition of GFP to the C-terminus of the murine GnRH-R does not alter the rate of internalization.

Response of LNCaP spheroids after treatment with an alpha-particle emitter (213Bi)-labeled anti-prostate-specific membrane antigen antibody (J591)

A theoretical drawback to alpha-particle therapy with 213Bi is the short range of the particle track coupled with the short half-life of the radionuclide, thereby potentially limiting effective cytotoxicity to rapidly accessible, disseminated individual tumor cells (e.g., as in leukemia). In this work, a prostate carcinoma spheroid model was used to evaluate the feasibility of targeting micrometastatic clusters of tumor cells using 213Bi-labeled anti-prostate-specific membrane antigen (PSMA) antibody, J591. In prostate cancer, vascular dissemination of tumor cells or tumor cell clusters to the marrow constitutes an important step in the progression of this disease to widespread skeletal involvement, an incurable state. Such prevascularized clusters are ideal targets for radiolabeled antibodies because the barriers to antibody penetration that are associated with the capillary basal lamina have not yet formed. Beta- and gamma-emitting radionuclides such as 131I, which are widely used in radioimmunotherapy, are not expected to be effective when targeting single cells or small cell clusters. This is because the range of the emissions is one to two orders of magnitude greater than the target size, and the energy deposited per traversal is insufficient to produce any significant radiobiological effect. Spheroids of the prostate cancer cell line, LNCaP-LN3, were used as a model of prevascularized micrometastases; their response to an anti-PSMA antibody, J591, radiolabeled with the alpha-particle emitter 213Bi (T(1/2), 45.6 min.) has been measured. The time course of spheroid volume reductions was found to be sensitive to the initial spheroid volume. J591 labeled with 0.9 MBq/ml 213Bi resulted in a 3-log reduction in spheroid volume on day 33, relative to control, for spheroids with an initial diameter of 130 microm; 1.8 MBq/ml were required to achieve a similar response for spheroids with an initial diameter of 180 microm. Equivalent spheroid responses were observed after 12 Gy of acute external beam photon irradiation. Monte Carlo-based microdosimetric analyses of the 213Bi decay distribution in individual spheroids of 130-microm diameter yielded an average alpha-particle dose of 3.7 Gy to the spheroids, resulting in a relative biological effectiveness factor of 3.2 over photon irradiation. The activity concentrations used in the experiments were clinically relevant, and this work supports the possibility of using 213Bi-labeled antibodies not only for disseminated single tumor cells, as found in patients with leukemia, but also for micrometastatic tumor deposits up to 180 microm in diameter (1200 cells).

Transurethral microwave thermotherapy for symptomatic benign prostatic hyperplasia: short-term experience with Prostcare

PURPOSE

To assess our short-term experience with transurethral microwave thermotherapy (TUMT) for symptomatic benign prostatic hyperplasia (BPH).

PATIENTS AND METHODS

From August 1993 through July 1994, in total 65 patients with symptomatic BPH were enrolled into this study. The patients' ages ranged from 56 to 95 years with a mean of 70 years. Under local anesthesia with intraurethral instillation of Xylocaine jelly only, all patients received one session of TUMT for up to 60 min with Prostcare equipment. Uroflowmetry was performed and international prostatic symptom score (IPSS) determined before 3 and 6 months after TUMT for assessment of efficacy. All adverse events were recorded and evaluated for clinical relevance.

RESULTS

At 3 and 6 months following TUMT, the mean IPSS decreased from 19.7 +/- 6.8 (baseline) to 12.8 +/- 8.2 (-46%) and to 15.5 +/- 9.0 (-21%), respectively; the maximal urine flow rate at 3 and 6 months increased from 9.1 +/- 4.8 ml/s (baseline) to 11.0 +/- 4.9 ml/s (+21%) and to 10.9 +/- 5.6 ml/s (+19%), respectively. During TUMT, burning sensation was the most frequent complaint (38.5%), followed by urethral discomfort (29.2%) and urgency (9.2%). Two patients (3.1%) interrupted TUMT, because of intolerable pain. Following TUMT micturition pain (73.8%) and gross hematuria (45.9%) were the most adverse events. Most of these adverse events disappeared within 2 weeks. One patient suffered from skin erosion over the penoscrotal junction 1 week later. None had retrograde ejaculation; 1 patient complained of erectile dysfunction.

CONCLUSION

Although the efficacy of TUMT with Prostcare became less prominent 6 months after TUMT, TUMT was still a tolerable, safe alternative treatment of BPH, especially in patients who were not suitable for transurethral resection of the prostate or anesthesia.

Expression of nm23-H1 in transitional cell carcinoma of the upper urinary tract

Transitional cell carcinoma of the upper urinary tract is an uncommon neoplasm. Relatively little information is available regarding the clinical relevance of molecular markers. This study was performed to examine the importance of nm23-H1 gene expression (NM23-H1) in this type of tumors. Immunohistochemical expression of NM23-H1 was analyzed in 90 cases of upper urinary tract cancer, and was compared for its prognostic significance with conventional biological indicators. High expression of NM23-H1 was found in 7 cases (8%), intermediate expression in 32 cases (36%), and low expression in 51 cases (57%). Reduced NM23-H1 (defined as intermediate or low level of expression) was associated with a higher histological grading (p=0.002), invasive tumor growth (p=0. 002), or an increased proliferating cell nuclear antigen labeling index (p=0.004). NM23-H1 tended to inversely relate to later recurrence or long-term survival (p=0.06), but, only tumor staging was found to be significant in predicting clinical outcome (p=0.002). nm23-H1 appears to function as a tumor suppressor for upper urinary tract cancer, however, evaluation of NM23-H1 provides limited prognostic information.

An alpha-particle emitting antibody ([213Bi]J591) for radioimmunotherapy of prostate cancer

A novel alpha-particle emitting monoclonal antibody construct targeting the external domain of prostate-specific membrane antigen (PSMA) was prepared and evaluated in vitro and in vivo. The chelating agent, N-[2-amino-3-(p-isothiocyanatophen-yl)propyl]-trans-cyclohexane-1, 2-diamine-N,N',N',N'',N''-pentaacetic acid, was appended to J591 monoclonal antibody to stably bind the 213Bi radiometal ion. Bismuth-213 is a short-lived (t 1/2 = 46 min) radionuclide that emits high energy alpha-particles with an effective range of 0.07-0.10 mm that are ideally suited to treating single-celled neoplasms and micrometastatic carcinomas. The LNCaP prostate cancer cell line had an estimated 180,000 molecules of PSMA per cell; J591 bound to PSMA with a 3-nM affinity. After binding, the radiolabeled construct-antigen complex was rapidly internalized into the cell, carrying the radiometal inside. [213Bi]J591 was specifically cytotoxic to LNCaP. The LD50 value of [213Bi]J591 was 220 nCi/ml at a specific activity of 6.4 Ci/g. The potency and specificity of [213Bi]J591 directed against LNCaP spheroids, an in vitro model for micrometastatic cancer, also was investigated. [213Bi]J591 effectively stopped growth of LNCaP spheroids relative to an equivalent dose of the irrelevant control [213Bi]HuM195 or unlabeled J591. Cytotoxicity experiments in vivo were carried out in an athymic nude mouse model with an i.m. xenograft of LNCaP cells. [213Bi]J591 was able to significantly improve (P < 0.0031) median tumor-free survival (54 days) in these experiments relative to treatment with irrelevant control [213Bi]HuM195 (33 days), or no treatment (31 days). Prostate-specific antigen (PSA) was also specifically reduced in treated animals. At day 51, mean PSA values were 104 ng/ml +/- 54 ng/ml (n = 4, untreated animals), 66 ng/ml +/- 16 ng/ml (n = 6, animals treated with [213Bi]HuM195), and 28 ng/ml +/- 22 ng/ml (n = 6, animals treated with [213Bi]J591). The reduction of PSA levels in mice treated with [213Bi]J591 relative to mice treated with [213Bi]HuM195 and untreated control animals was significant with P < 0.007 and P < 0.0136, respectively. In conclusion, a novel [213Bi]-radiolabeled J591 has been constructed that selectively delivers alpha-particles to prostate cancer cells for potent and specific killing in vitro and in vivo.

Y chromosome sequence variation and the history of human populations

Binary polymorphisms associated with the non-recombining region of the human Y chromosome (NRY) preserve the paternal genetic legacy of our species that has persisted to the present, permitting inference of human evolution, population affinity and demographic history. We used denaturing high-performance liquid chromatography (DHPLC; ref. 2) to identify 160 of the 166 bi-allelic and 1 tri-allelic site that formed a parsimonious genealogy of 116 haplotypes, several of which display distinct population affinities based on the analysis of 1062 globally representative individuals. A minority of contemporary East Africans and Khoisan represent the descendants of the most ancestral patrilineages of anatomically modern humans that left Africa between 35,000 and 89,000 years ago.

Population genetic implications from sequence variation in four Y chromosome genes

Some insight into human evolution has been gained from the sequencing of four Y chromosome genes. Primary genomic sequencing determined gene SMCY to be composed of 27 exons that comprise 4,620 bp of coding sequence. The unfinished sequencing of the 5' portion of gene UTY1 was completed by primer walking, and a total of 20 exons were found. By using denaturing HPLC, these two genes, as well as DBY and DFFRY, were screened for polymorphic sites in 53-72 representatives of the five continents. A total of 98 variants were found, yielding nucleotide diversity estimates of 2.45 x 10(-5), 5. 07 x 10(-5), and 8.54 x 10(-5) for the coding regions of SMCY, DFFRY, and UTY1, respectively, with no variant having been observed in DBY. In agreement with most autosomal genes, diversity estimates for the noncoding regions were about 2- to 3-fold higher and ranged from 9. 16 x 10(-5) to 14.2 x 10(-5) for the four genes. Analysis of the frequencies of derived alleles for all four genes showed that they more closely fit the expectation of a Luria-Delbrück distribution than a distribution expected under a constant population size model, providing evidence for exponential population growth. Pairwise nucleotide mismatch distributions date the occurrence of population expansion to approximately 28,000 years ago. This estimate is in accord with the spread of Aurignacian technology and the disappearance of the Neanderthals.

An in vitro monitoring system for simulated thermal process in cryosurgery

This paper describes a new in vitro experimental model that records temperature changes over a culture plate, which then can be used to assess the biological effects of cryosurgery. A cryoprobe and 16 thermocouples set up by a computer control system were used to monitor the temperature changes during freezing and thawing in a culture plate, and the data were used to create a temperature profile of the entire plate. Location of the thermocouples was confirmed by a digital camera viewing from under the plate, and temperature changes at any point in the interpolated areas were estimated using a curve fitting method. The estimated temperature was checked by sampling with four additional randomly placed thermocouples. Linear regression analysis showed that the estimated temperature and measured temperature were very close (correlation coefficients 0.98-0.99). MBT-2 tumor cells were cultured and then subjected to simulated cryosurgery. The surviving cells were stained with crystal violet and the cell death boundary was detected by image processing. Temperature history at the cell death boundary was retrieved and analyzed. With this system it is possible to recreate the temperature changes that result in a certain biological effect (such as cell death) during the process of simulated cryosurgery.

Transitional cell carcinoma in dialysis patients

OBJECTIVE

The aim of our study was to determine whether there is an increased incidence of urothelial cancer, especially transitional cell carcinoma (TCC), in uremic patients on dialysis.

METHODS

Retrospective chart analyses were completed for 1,910 uremic patients undergoing maintenance dialysis between January 1987 and December 1997. The incidence of urinary tract cancer was assessed. Only the patients with cancers diagnosed after start of dialysis were enrolled in the study.

RESULTS

Of the 1,910 patients, 70 had concomitant urinary tract cancers. Nineteen patients (0.99%), including 17 patients with TCC and 2 patients with renal cell carcinoma, were diagnosed after the initiation of dialysis. The average duration from dialysis to TCC diagnosis was 38.3 (range 2-144) months. Painless gross hematuria was the cardinal symptom in 16 of the 17 patients with TCC. In the 17 patients with TCC, no distant metastases were found at the time of diagnosis. Fourteen patients (82.3%) were stage 0 or A, and 1 patient was stage B1.

CONCLUSIONS

The 0.89% incidence of TCC in our dialysis patients was high as compared with that of the general population. The risks of developing urinary TCC in dialysis patients were examined, and we suggest that immunosuppressive stage, dialysis procedure, and chronic bladder irritation (decreased urinary wash effect) may play a part in the development of urinary TCC in dialysis patients. Early detection of hematuria due to regular visits and decreased exposure of urinary tract epithelium to carcinogens from urine may explain why early-stage TCC was seen in most of our patients.

Comparison of topical nedocromil sodium and oral terfenadine for the treatment of seasonal allergic conjunctivitis

This double-masked, comparative, multicenter study was conducted to assess the onset of action and tolerability of nedocromil sodium 2% ophthalmic solution BID, 60-mg terfenadine tablets BID, and placebo in the treatment of seasonal allergic conjunctivitis. Two hundred sixty-eight patients in whom seasonal allergic conjunctivitis was diagnosed were assigned to 1 of 3 groups and administered study medication for 4 weeks. Patients' mean age was 33 years (range, 12 to 68 years); 57.8% (155 of 268) were female. Demographic characteristics were similar in all 3 groups. Although all 3 groups showed improvement in ocular symptoms, nedocromil sodium was associated with a statistically significantly faster onset of action than was terfenadine or placebo (P = 0.038). During the study, 29 nedocromil sodium-treated patients (36.7%) achieved control of symptoms in < or =2 minutes, and 61 (77.2%) achieved control in < or =15 minutes. The corresponding numbers were 21 (24.7%) and 50 (58.8%) in the terfenadine group and 25 (29.1%) and 48 (55.8%) in the placebo group. The frequency of adverse events was low and similar between groups (nedocromil sodium, 26; terfenadine, 32; placebo, 32). No severe treatment-related adverse events were reported. In conclusion, nedocromil sodium had a significantly faster onset of action than did terfenadine or placebo.

Growth and characterization of LNCaP prostate cancer cell spheroids

Cells from the prostate tumor cell line LNCaP have been grown as spheroids. The growth kinetics of the spheroids have been characterized by fitting a Gompertz equation to spheroid growth curves. The proliferation state of cells within spheroids of different diameters was assessed by bromodeoxyuridine staining. Scanning and electron transmission microscopy were performed to determine the ultrastructure of the spheroids. Prostate-specific antigen (PSA) secretion was monitored throughout spheroid growth. Consistent with Gompertzian kinetics, the volume of LNCaP spheroids initially increased exponentially and then reached a plateau. The doubling time during the exponential phase was 29 +/- 4 h. A core of nonproliferating cells was seen in spheroids with a diameter of 400 microm; at a diameter of 600 microm, a necrotic core had formed. In smaller, 200-microm diameter spheroids, a core of nonproliferating cells was not seen, but proliferating cells were concentrated at the spheroid periphery. Electron microscopy showed that the spheroids were enveloped by an extracellular matrix and that cell adhesion within the spheroids was due in part to desmosomes. PSA secretion by the spheroids could be modeled as originating from a spherical shell whose thickness was independent of overall spheroid diameter. The shell thickness obtained by fitting an appropriate equation to the data was consistent with that determined from the bromodeoxyuridine studies. LNCaP cells exhibit several important features of prostate cancer cells; in vivo, they are androgen responsive, and they express prostatic acid phosphatase, PSA, and prostate-specific membrane antigen. LNCaP spheroids provide a simple but relevant model for the study of drug delivery and response in prostate cancer.

Genome-wide mapping with biallelic markers in Arabidopsis thaliana

Single-nucleotide polymorphisms, as well as small insertions and deletions (here referred to collectively as simple nucleotide polymorphisms, or SNPs), comprise the largest set of sequence variants in most organisms. Positional cloning based on SNPs may accelerate the identification of human disease traits and a range of biologically informative mutations. The recent application of high-density oligonucleotide arrays to allele identification has made it feasible to genotype thousands of biallelic SNPs in a single experiment. It has yet to be established, however, whether SNP detection using oligonucleotide arrays can be used to accelerate the mapping of traits in diploid genomes. The cruciferous weed Arabidopsis thaliana is an attractive model system for the construction and use of biallelic SNP maps. Although important biological processes ranging from fertilization and cell fate determination to disease resistance have been modelled in A. thaliana, identifying mutations in this organism has been impeded by the lack of a high-density genetic map consisting of easily genotyped DNA markers. We report here the construction of a biallelic genetic map in A. thaliana with a resolution of 3.5 cM and its use in mapping Eds16, a gene involved in the defence response to the fungal pathogen Erysiphe orontii. Mapping of this trait involved the high-throughput generation of meiotic maps of F2 individuals using high-density oligonucleotide probe array-based genotyping. We developed a software package called InterMap and used it to automatically delimit Eds16 to a 7-cM interval on chromosome 1. These results are the first demonstration of biallelic mapping in diploid genomes and establish means for generalizing SNP-based maps to virtually any genetic organism.