European non-invasive trisomy evaluation (EU-NITE) study: a multicenter prospective cohort study for non-invasive fetal trisomy 21 testing

OBJECTIVE

To evaluate the performance of a directed non-invasive prenatal testing method of cell-free DNA analysis for fetal trisomy 21 (T21) by shipping the whole blood samples from Europe to a laboratory in the USA.

METHODS

A European multicenter prospective, consecutive cohort study was performed enrolling pregnant women from Sweden and the Netherlands. Blood samples were drawn just prior to a planned of invasive diagnostic procedure in a population at increased risk for fetal T21 and then shipped to the USA without any blood processing. Chromosome-selective sequencing was carried out on chromosome 21 with reporting high risk or low risk of T21. Karyotyping or rapid aneuploidy detection was used as the clinical reference standard.

RESULTS

Of the 520 eligible study subjects, a T21 test result was obtained in 504/520 (96.9%). Risk assessment was accurate in 503/504 subjects (99.8%). There was one false negative result for T21 (sensitivity 17/18, 94.4%, and specificity 100%).

CONCLUSION

This is the first prospective European multicenter study showing that non-invasive prenatal testing using directed sequencing of cell-free DNA applied to blood samples shipped across the Atlantic Ocean, is highly accurate for assessing risk of fetal T21.

Investigation on exceptional fuel CRUD samples by using radioactivity ratios of cobalt isotopes

Elemental analysis and radioactivity measurements were carried out for fuel CRUD samples obtained from a nuclear power plant. Comparisons were made for the relationship between (58)Co radioactivity and Ni content and for the radioactivity ratios of (58)Co to (60)Co of the samples. We found a peculiar radioactivity relationship from one of the samples and were able to further evaluate this based on its unique fuel exchange history. This analysis can be useful to enhance the data credibility of CRUD samples.

Maternal plasma cell-free fetal and maternal DNA at 11-13 weeks' gestation: relation to fetal and maternal characteristics and pregnancy outcomes

OBJECTIVE

To examine the possible relationship between maternal and fetal characteristics and pregnancy outcomes on fetal and maternal cell-free (cf) DNA in maternal plasma at 11-13 weeks' gestation.

METHODS

cfDNA was extracted from maternal plasma of 1,949 singleton pregnancies and chromosome-selective sequencing was used to determine the proportion of cfDNA and total cfDNA counts which was of fetal and maternal origin. Multivariate regression analysis was used to determine whether specific maternal and fetal characteristics and pregnancy complications, such as preeclampsia (PE), early spontaneous preterm birth (SPB) and delivery of small for gestational age (SGA) neonates, were significant predictors of fetal and maternal cfDNA in maternal plasma.

RESULTS

The fetal and maternal cfDNA plasma concentration increased with serum pregnancy-associated plasma protein-A and free β-human chorionic gonadotropin level, was higher in women of Afro-Caribbean and East-Asian racial origin than in Caucasians, and lower in smokers, but it was not significantly altered in pregnancies complicated by PE, SPB or SGA. The fetal cfDNA level was inversely related to maternal weight and uterine artery pulsatility index, and maternal cfDNA increased with maternal weight.

CONCLUSIONS

The fetal and maternal cfDNA level in maternal plasma is affected by maternal and fetal characteristics, but it is not altered in pregnancy complications.

Trisomy 13 detection in the first trimester of pregnancy using a chromosome-selective cell-free DNA analysis method

OBJECTIVE

To assess the performance of chromosome-selective sequencing of maternal plasma cell-free DNA (cfDNA) in non-invasive prenatal testing for trisomy 13.

METHODS

Two-phase case-control study on a single plasma sample per case. The first phase was used to optimize the trisomy 13 algorithm, which was then applied to a second dataset to determine the risk score for trisomy 13 by laboratory personnel who were blinded to the fetal karyotype.

RESULTS

In the first phase, trisomy 13 risk scores were given for 11 cases of trisomy 13 and 145 euploid cases at 11-13 weeks' gestation. The test identified seven (63.6%) cases of trisomy 13 with no false positives. The trisomy 13 algorithm was subsequently modified and the trisomy 13 risk score was > 99% in all 11 cases of trisomy 13 and < 0.01% in all 145 euploid cases. In the second phase, the new algorithm was used to generate trisomy 13 risk scores for 10 cases of trisomy 13 and 1939 euploid cases. The trisomy 13 risk scores were > 99% in eight (80.0% (95% confidence interval (CI), 49.0-94.3%)) cases of trisomy 13. In the 1939 euploid cases the risk score for trisomy 13 was < 0.01% in 1937 (99.9%), 0.79% in one, and > 99% in one. Therefore, at the predefined risk cut-off of 1% for classifying a sample as high or low risk, the false-positive rate (FPR) was 0.05% (95% CI, 0.0-0.3%).

CONCLUSIONS

Chromosome-selective sequencing of cfDNA can detect the majority of cases of trisomy 13 at an FPR of less than 0.1%.

Palliative care of malignant ureteral obstruction with polytetrafluoroethylene membrane-covered self-expandable metallic stents: initial experience

Purpose

We assessed the efficacy and safety of insertion of a polytetrafluoroethylene membrane-covered self-expandable metallic stent (UVENTA stent) for palliation of malignant ureteral obstruction on the basis of our early results.

Materials and Methods

Eighteen patients underwent UVENTA stent insertion for extrinsic malignant ureteral obstructions of 20 ureters. The UVENTA stents were deployed retrogradely under cystoscopy and fluoroscopy. Candidates for the procedure had preexisting double-J stents that were nonfunctional or caused excessive bladder irritation. We recorded the success and patency rate in addition to any complications associated with the procedure.

Results

The mean length of obstruction was 10.6 cm (range, 2 to 20 cm). Two ureters were obstructed in the upper ureter, 9 in the lower ureter, and 9 in multiple levels of ureter. Simultaneous balloon dilation was performed in 12 ureters. UVENTA stents were successfully inserted in all patients. No obstruction of the UVENTA stents occurred during the mean follow-up period of 7.3 months (patency rate 100%), but de novo ureteral obstruction developed in 4 ureters. There were no instances of stone formation, hyperplastic reaction, encrustation, or migration. Abnormally elevated serum creatinine decreased to normal levels and hydronephrosis gradually resolved during the 4 weeks after UVENTA insertion. No significant complications developed except for transient and self-limiting hematuria and mild lower abdominal pain.

Conclusions

UVENTA stents may relieve malignant ureteral obstruction safely and easily. Long-term follow-up is necessary to assess the role of this stent in the treatment of malignant ureteral obstruction.

Loss of E-cadherin in multidrug resistant breast cancer cell line MCF-7/Adr: possible implication in the enhanced invasive ability

BACKGROUND

Recently, many observations have drawn researchers' attention to study drug resistance and invasion/metastasis as a single entity. However, little evidence is available about the relationship between the multiple drug resistance (MDR) and invasion so far.

AIM

To study the relationship between the multiple drug resistance and invasive-metastatic phenotypes in cancer cells.

MATERIALS AND METHODS

In this study, we compared the biological alterations of drug-resistant cells with their parental control and demonstrated that the drug-resistant cells have acquired enhanced invasive ability in addition to their acquired MDR phenotype.

RESULTS

Motility and invasiveness assays revealed that MCF-7 / Adr had an invasive phenotype. Light and electron microscopy showed loss of cell-cell clustering after trypsinization, loss of tight junctions and desmosomes, ultrastructural changes to the actin network and nucleus, loss of epithelial characters, and increase in filopodia in the drug resistant cell line. A major component of cell-cell junctions, E-cadherin, was shown to be expressed on the protein and RNA levels in MCF-7 but not MDF-7 / Adr cells. More protrusions (pseudopodia) on the cell surface were found in MCF-7 / Adr cells, which enable the cells to migrate and invade / metastasize. Examination of ultrastructural morphology revealed that great changes occurred in drug resistant cancer cells including absence of tight junctions/desmosomes, and dislocation of cytoskeleton microfilaments. Since the cadherin / catenin complexes are further associated with the major cytoskeleton components at cell-cell junctions, we measured E-cadherin expression in drug-resistant cells. Both Western blot and immunocytochemical staining demonstrated the loss of E-cadherin expression in MCF-7 / Adr cells. Further, RNA in situ hybridization results confirmed that loss of E-cadherin expression occurred at the transcriptional level.

CONCLUSIONS

The drug-resistant MCF-7/Adr cells were found to be more invasive/metastatic than their parental control, possibly related to the loss of E-cadherin expression.

Ureteral injury in gynecologic surgery: a 5-year review in a community hospital

Purpose

We reviewed the cases of ureteral injury during gynecologic surgeries in a community hospital and attempted to find possible options for alleviating these distressing situations.

Materials and Methods

A total of 2,927 patients underwent gynecologic surgeries in the last 5 years at our hospital. We retrospectively analyzed the cases, particularly the possible risk factors and management according to the time of detection of the injury. Thirty-five cases (1.2%) were identified with ureteral injury in a total of 2,927 gynecologic surgeries. Risk factors included endometriosis, pelvic inflammatory disease, previous pelvic surgery, history of pelvic radiation, and congenital anomalies. Among 2,927 patients, 522 had predisposing factors for ureteral injuries.

Results

The incidence of ureteral injury in laparoscopic cases was 1.1%, similar to the cases of laparotomy (1.2%). The rate of ureteral injury was significantly higher in the group with risk factors (2.7%) than in the group without risk factors (0.9%; p=0.002). Prophylactic ureteral stenting was performed in 101 of 522 patients with risk factors according to the gynecologic surgeon's preference. The injury rate (1.0%) in the stenting group was lower than that in the non-stenting group (3.1%; p=0.324). Management of ureteral injuries was successful in all cases. Of the patients with postoperatively diagnosed injuries, two patients were managed with secondary procedures, such as retrograde balloon dilatation or ureteroneocystostomy.

Conclusions

The incidence of ureteral injury was significantly higher in cases having risk factors than in cases without risk factors. Surgeons should be cautious to avoid ureteral injury during gynecologic surgery, especially in patients with risk factors.

Screening of plant extracts for human tyrosinase inhibiting effects

Screening for tyrosinase (TYR) inhibitors potentially useful for control of skin pigmentation has been hampered by the limited availability of human TYR. To overcome this hurdle, we have established human embryonic kidney (HEK293)-TYR cells that constitutively express human TYR. In the current study, we assayed human TYR inhibition activities of 50 plant extracts using the lysates of transformed HEK293-TYR cells. The strongest inhibition of human TYR was shown by the extract of Vaccinium bracteatum Thunberg, followed by the extract of Morus bombycis Koidzumi. The former extract did not inhibit mushroom TYR activity whereas significant inhibition was observed with the latter extract, demonstrating the importance of using human TYR in the screening for human TYR inhibitors. Upon liquid-liquid partitioning of the extract from V. bracteatum, the active constituents were enriched in the ethyl acetate fraction, and the subsequent preparatory thin-layer chromatography identified p-coumaric acid (PCA) as the main active constituent. The hypo-pigmentation of PCA was verified in the MelanoDerm™ Skin Model. This study demonstrates that transformed HEK293-TYR cells could expedite the discovery of human TYR-specific inhibitors from natural sources which might be useful in the control of skin pigmentation.

Spectroscopic studies on U(VI)-salicylate complex formation with multiple equilibria

This study investigates multiple equilibria related to the formation of the U(VI)-salicylate complex in a pH range of 3.0–5.5 using UV-Vis absorption and fluorescence measurement techniques. The absorbance changes at the characteristic charge-transfer bands of the complex were monitored, and the results indicated the presence of multiple equilibria and the formation of both 1:1 and 1:2 (U(VI):salicylate) complexes possessing bi-dentate chelate structures. The determined step-wise formation constants (log K 1:1 and log K 1:2) are as follows: 12.5 ± 0.1 and 11.4 ± 0.2 for salicylate, 11.2 ± 0.1 and 10.1 ± 0.2 for 5-sulfosalicylate, and 12.4 ± 0.1 and 11.4 ± 0.1 for 2,6-dihydroxybenzoate, respectively. The molar absorptivities of the complexes are also provided. Furthermore, time-resolved laser-induced luminescence spectra of U(VI) species demonstrate the presence of both a dynamic and static quenching process upon the addition of a salicylate ligand. Particularly for the luminescent hydroxouranyl species, a strong static quenching effect is observed. The results suggest that both the UO2(HSal)+ and the U(VI)–Sal chelate complexes serve as ground-state complexes that induce static quenching. The Stern–Volmer parameters were derived based on the measured luminescent intensity and lifetime data. The static quenching constants (log K S) obtained are 3.3 ± 0.1, 4.9 ± 0.1, and 4.4 ± 0.1 for UO2 2+, (UO2)2(OH)2 2+ and (UO2)3(OH)5 +, respectively.