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Palo Alto, CA, United States

Oktem O.,Womens Health Center | Oktem O.,American Hospital Womens Health Center | Alper E.,Womens Health Center | Balaban B.,Womens Health Center | And 4 more authors.
Fertility and Sterility | Year: 2011

Slow-freezing and vitrification methods of human ovarian tissue cryopreservation were compared in terms of primordial follicle count and in vitro antimüllerian hormone (AMH) and estradiol production. Compared with fresh and slow-frozen ovaries, vitrified ovaries contained statistically significantly fewer primordial follicles and produced statistically significantly less AMH in vitro. Estradiol production from slow-frozen and vitrified ovaries was similar but statistically significantly lower than from fresh cultured strips. © 2011 by American Society for Reproductive Medicine.

Devgun M.S.,Clinical Laboratories | El-Nujumi A.M.,NHS Lanarkshire | Abara R.,NHS Lanarkshire | Armbruster D.,Abbott Laboratories | Adeli K.,University of Toronto
Clinical Biochemistry | Year: 2015

Objective: Measurement of total and direct bilirubin is routinely performed for the differential diagnosis of hyperbilirubinemias. The diagnostic efficiency of a test is dependent on the chosen clinical decision limit. This study is designed to address the clinical decision limits for direct bilirubin. Design and methods: Routine laboratory method was used to measure total and direct bilirubin in children up to the age of 18. years. Case study data and serum from a group of healthy children were analyzed and statistical exercise was performed to establish decision limits. Results: The reference interval for total bilirubin was 1-12. μmol/L and for direct bilirubin 1-9. μmol/L with the median direct bilirubin of 3. μmol/L. In 17% of children with non-pathological jaundice, median total bilirubin was 173. μmol/L, median direct bilirubin was 8. μmol/L and median direct bilirubin percent was 49%. From birth direct bilirubin percentage decreased until total bilirubin was 41. μmol/L, then it remained at ≤. 10%. Albumin increased with age, and was on average 2.4. g/L higher when measured using bromocresol-green compared with bromocresol-purple. An increased amount of direct bilirubin was observed when albumin (detected using the bromocresol-purple method) was >. 35. g/L. Conclusions: Direct bilirubin concentration of ≥. 10. μmol/L should be used to consider the presence of conjugated hyperbilirubinemia provided that total bilirubin is also above the reference interval. A high direct bilirubin percentage is unlikely to offer any clinical value when total bilirubin is not increased. It is, however, a useful diagnostic tool when there is a persistence of hyperbilirubinemia or when total bilirubin increases during times of stress with direct bilirubin >. 10%. © 2014 .

Sener G.,Hacettepe University | Ozgur E.,Hacettepe University | Rad A.Y.,Clinical Laboratories | Uzun L.,Hacettepe University | And 2 more authors.
Analyst | Year: 2013

Procalcitonin (PCT) is a promising biomarker for identification of the origin and severity of sepsis, which is a deadly body infection. In this work, we report the preparation of a surface plasmon resonance (SPR) biosensor which utilizes a molecular imprinted polymer surface for rapid and reliable detection of PCT. The molecular imprinted surface was prepared using a microcontact imprinting technique, in which PCT molecules were first immobilized onto a glass support and brought into contact with a solution of 2-hydroxyethyl methacrylate (HEMA) and ethylene glycol dimethacrylate (EGDMA) on a SPR sensor, then the polymerization process was performed. After removal of the PCT molecules, specific molecular recognition sites were obtained, where PCT molecules can selectively rebind, only at the surface of the polymer matrix. PCT detection studies were carried out using PCT solutions in phosphate buffer and simulated blood plasma (SBP) at different concentrations. The SPR biosensor can detect very low concentrations (9.9 ng mL-1) of PCT within approximately 1 h, in both phosphate buffer and SBP. High selectivity of the biosensor against PCT was also demonstrated in the presence of several competitive proteins such as human serum albumin, myoglobin and cytochrome c. © 2013 The Royal Society of Chemistry.

Bertholf R.L.,Florida College | Johannsen L.M.,Clinical Laboratories | Reisfield G.M.,Florida College
Journal of Analytical Toxicology | Year: 2015

Urine drug testing (UDT) is an emerging standard of care in the evaluation and treatment of chronic non-cancer pain patients with opioid analgesics. UDT may be used both to verify adherence with the opioid analgesic regimen and to monitor abstinence from non-prescribed or illicit controlled substances. In the former scenario, it is vital to determine whether the drug is present in the urine, even at low concentrations, because failure to detect the drug may lead to accusations of opioid abuse or diversion. Opiate immunoassays typically are developed to detect morphine and are most sensitive to morphine and codeine. Although many opiate immunoassays also detect hydrocodone (HC) and/or hydromorphone (HM), sensitivities for these analytes are often much lower, increasing the possibility of negative screening results when the drug is present in the urine. We selected 112 urine specimens from patients who had been prescribed HC or hydromorphone but were presumptive negative by the Roche Online DAT Opiate II™ urine drug screening assay, which is calibrated to 300 ng/mL morphine. Using a GC/MS confirmatory method with a detection limit of 50 ng/mL both for HC and for HM, one or both of these opiates were detected in 81 (72.3%) of the urine specimens. Examination of the raw data from these presumptive negative opiate screens revealed that, in many cases, the turbidity signal was greater than the signal obtained for the negative control, but less than the signal for the 300 ng/mL (morphine) threshold calibrator. A receiver operating characteristic curve generated for the reciprocal of the ratio of turbidity measurements in the patient specimens and negative (drug-free) controls, against the presence or absence of HC and/or HM by confirmatory analyses, produced an area under the curve of 0.910. We conclude that this opiate immunoassay has sufficient sensitivity to detect HC and/or HM in some urine specimens that screen presumptive negative for these commonly prescribed opiates at the established threshold. © The Author 2014.

Albacar G.,Rovira i Virgili University | Sans T.,Clinical Laboratories | Martin-Santos R.,Neuropsychopharmacology Program | Garcia-Esteve L.,Neuropsychopharmacology Program | And 9 more authors.
Journal of Affective Disorders | Year: 2011

Context: Iron deficiency is the most common nutritional problem experienced by childbearing women, and postpartum depression (PPD) is the most common psychiatric disorder seen during the first year after delivery. The possible link between iron deficiency and PPD is not clear. Objective: To evaluate whether iron status 48 h after delivery was associated with PPD. Our hypothesis was that iron deficiency would be associated with PPD. Design: This was a prospective cohort study of depression-free women studied in the postpartum period. Setting: Women who give birth at obstetric units in several general hospitals in Spain. Participants: A subsample of 729 women was included in the present study after exclusion of women with high C-reactive protein (CRP) and other diseases known to interfere with iron metabolism. Main outcome measures: We evaluated depressive symptoms at 48 h, 8 weeks and 32 weeks postpartum and used a diagnostic interview to confirm the diagnosis of major depression. A blood sample obtained 48 h after delivery was used to measure the following iron storage parameters: ferritin, transferrin (Tf), free iron and transferrin saturation (TfS) and the inflammatory marker CCRP. Results: Overall, the women in the study had low iron concentrations (8.8 ± 6.9 μmol/L) and low TfS (12.6 ± 9.6%) but normal ferritin and Tf concentrations. A total of 65 women (9%) developed PPD during the 32 week postpartum period; these women also had a lower ferritin concentration (15.4 ± 12.7 μg/L vs. 21.6 ± 13.5 μg/L, P = 0.002). A strong association between ferritin and PPD was observed (odds ratio = 3.73, 95% CI: 1.84-7.56; P = 0.0001 for ferritin cutoff value of 7.26 μg/L). In our study, ferritin concentrations have a high specificity but low sensitivity in predicting PPD. Conclusions: These findings support the role of iron in the etiology of PPD and the use of ferritin as a marker of iron deficiency in the postpartum period. We believe that this topic deserves further investigation. © 2010 Elsevier B.V. All rights reserved.

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