544 research outputs found
Glutathione S-transferase activity and isoenzyme composition in benign ovarian tumours, untreated malignant ovarian tumours, and malignant ovarian tumours after platinum/cyclophosphamide chemotherapy.
Glutathione S-transferase (GST) isoenzyme composition, isoenzyme quantities and enzymatic activity were investigated in benign (n = 4) ovarian tumours and malignant ovarian tumours, before (n = 20) and after (n = 16) chemotherapy. Enzymatic activity of GST in cytosols was measured by determining 1-chloro-2,4-dinitrobenzene conjugation with glutathione, cytosolic GST subunits were determined by wide pore reversed phase HPLC, using a S-hexylglutathione-agarose affinity column, and isoelectric focussing. Both GST activity and GST pi amount were not related to histopathologic type, differentiation grade, or tumour volume index in untreated malignant tumours. GST isoenzyme patterns were identical in benign tumours and malignant tumours before and after platinum/cyclophosphamide chemotherapy, while GST pi was the predominant transferase. Mean GST activity and GST pi amount were decreased (P < 0.05) in malignant ovarian tumours after platinum/cyclophosphamide chemotherapy compared to untreated ovarian malignant tumours. No relation was found in untreated ovarian tumours between GST pi amount and response to platinum/cyclophosphamide chemotherapy. Thus, within the limitations of the current study no arguments were found for a role of GST in in vivo drug resistance of malignant ovarian tumours to platinum/cyclophosphamide chemotherapy
The Effect of IFN-γ, Alum and Complete Freund Adjuvant on TNP-KLH Induced Ig.G1, IgE and IgG2a Responses in Mice
Adjuvants are considered to play an important role in directing the
isotype and amount of antibodies produced upon immunization by
conducting the development of either Th-1 or Th-2 cells upon T-cell
stimulation. This is based on the different cytokine production
patterns that were observed after in vitro resttmulation of T cells
isolated from mice immunized with antigen either adsorbed on alum or
emulsified in complete Freund adjuvant (CFA). However, other studies
suggest that primarily the type of antigen determines which isotypes
are produced and to what extent. In these studies, however, IgE was
not determined. Therefore, this study examined whether alum and CFA
influenced the amount and/or ratio of IgG1, IgE and IgG2a produced
after TNP-KLH immunization. Similar levels of IgG1, IgE and IgG2a
antibodies were found upon immunization with TNP-KLH either adsorbed
on alum or emulsified in CFA. Moreover, administration of IFN-γ in
combination with TNP-KLH adsorbed on alum did not increase the
amount of IgG2a produced. IFN-γ treatment resulted in an increased
IL-6 and decreased IFN-γ production by spleen cells upon Con A
stimulation, whereas it did not change the IL-4 production in
similar conditions. The presented results suggest that upon
immunization with TNP-KLH high IL-4 levels are produced, resulting
in an antibody response that is dominated by IgG1, independent of the
adjuvant employed. The IL-4 inducing property of TNP-KLH is
substantiated by the finding that repeated immunization of mice with
TNP-KI, without adjuvant, increases the serum total IgE level. The
presented data suggest that the carrier part of TNP-KLH
preferentially results in Th-2 cell activity after which the
adjuvant merely enhances the antibody responses generated
Recommendations for future research in relation to pediatric pulmonary embolism: communication from the SSC of the ISTH
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142464/1/jth13902_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/142464/2/jth13902.pd
Apixaban overdose in children: case report and proposed management. A brief communication from the Pediatric and Neonatal Thrombosis and Hemostasis SSC of ISTH
\ua9 2024 The Authors. Background: Direct oral anticoagulants are commonly prescribed for adults and increasingly also for children requiring anticoagulation therapy. While household medications should not be accessible to children, accidental, and intentional overdoses occur. Key Clinical Question: How should apixaban overdose in children be managed?. Clinical Approach: We present a case of an accidental overdose with the factor Xa antagonist apixaban in a young child and propose an approach to the management of cases of apixaban overdose in children. Conclusion: Given the increasing use of direct oral anticoagulants, it is important to have an approach to the management of overdose of these medications
Coagulopathy in Zellweger spectrum disorders: a role for vitamin K
Introduction: Zellweger spectrum disorders (ZSDs) are caused by an impairment of peroxisome biogenesis, resulting in multiple metabolic abnormalities. This leads to a range of symptoms, including hepatic dysfunction and coagulopathy. This study evaluated the incidence and severity of coagulopathy and the effect of vitamin K supplementation orally and IV in ZSD. Methods: Data were retrospectively retrieved from the medical records of 30 ZSD patients to study coagulopathy and the effect of vitamin K orally on proteins induced by vitamin K absence (PIVKA-II) levels. Five patients from the cohort with a prolonged prothrombin time, low factor VII, and elevated PIVKA-II levels received 10 mg of vitamin K IV. Laboratory results, including thrombin generation, at baseline and 72 h after vitamin K administration were examined. Results: In the retrospective cohort, four patients (13.3%) experienced intracranial bleedings and 14 (46.7%) reported minor bleeding. No thrombotic events occurred. PIVKA-II levels decreased 38% after start of vitamin K therapy orally. In the five patients with a coagulopathy, despite treatment with oral administration of vitamin K, vitamin K IV caused an additional decrease (23%) of PIVKA-II levels and increased thrombin generation. Conclusion: Bleeding complications frequently occur in ZSD patients due to liver disease and vitamin K deficiency. Vitamin K deficiency is partly corrected by vitamin K supplementation orally, and vitamin K administered IV additionally improves vitamin K status, as shown by further decrease of PIVKA-II and improved thrombin generation
Design and Analysis of Dual Pressure Probes for Predicting Turbulence-Induced Vibration in Low Velocity Flow
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97074/1/AIAA2012-1881.pd
Screening for BRCA2 mutations in 81 Dutch breast–ovarian cancer families
We have analysed 81 families with a history of breast and/or ovarian cancer for the presence of germline mutations in BRCA2 with a number of different mutation screening techniques. The protein truncation test (PTT) for exons 10 and 11 detected four different frame-shifting mutations in six of these families. Four of the remaining 75 families had given positive linkage evidence for being due to BRCA2. In these families the entire coding region was analysed by single-strand conformational polymorphism, leading to the detection of a non-sense and a splice-site mutation in two of them. While these studies were in progress, Southern analysis of BRCA1 revealed that in our study-population of 81 families, 15 families were segregating either the exon 13 or exon 22 deletion in BRCA1 (Petrij-Bosch et al (1997) Nat Genet17: 341–345). This prompted us to examine BRCA2 in the remaining 58 families by Southern analysis, using two different restriction enzymes. No aberrations were found in the restriction patterns. Thus, contrary to BRCA1, large genomic rearrangements within the BRCA2 gene do not represent a major mutation mechanism among Dutch breast cancer families. © 2000 Cancer Research Campaig
Levels of Fibrinogen Variants Are Altered in Severe COVID-19
Background  Fibrinogen variants as a result of alternative messenger RNA splicing or protein degradation can affect fibrin(ogen) functions. The levels of these variants might be altered during coronavirus disease 2019 (COVID-19), potentially affecting disease severity or the thrombosis risk. Aim  To investigate the levels of fibrinogen variants in plasma of patients with COVID-19. Methods  In this case-control study, we measured levels of functional fibrinogen using the Clauss assay. Enzyme-linked immunosorbent assays were used to measure antigen levels of total, intact (nondegraded Aα chain), extended Aα chain (α E ), and γ' fibrinogen in healthy controls, patients with pneumococcal infection in the intensive care unit (ICU), ward patients with COVID-19, and ICU patients with COVID-19 (with and without thrombosis, two time points). Results  Healthy controls and ward patients with COVID-19 ( n  = 10) showed similar fibrinogen (variant) levels. ICU patients with COVID-19 who later did ( n  = 19) or did not develop thrombosis ( n  = 18) and ICU patients with pneumococcal infection ( n  = 6) had higher absolute levels of functional, total, intact, and α E fibrinogen than healthy controls ( n  = 7). The relative α E fibrinogen levels were higher in ICU patients with COVID-19 than in healthy controls, while relative γ' fibrinogen levels were lower. After diagnosis of thrombosis, only the functional fibrinogen levels were higher in ICU patients with COVID-19 and thrombosis than in those without, while no differences were observed in the other fibrinogen variants. Conclusion  Our results show that severe COVID-19 is associated with increased levels of α E fibrinogen and decreased relative levels of γ' fibrinogen, which may be a cause or consequence of severe disease, but this is not associated with the development of thrombosis.</p
Levels of Fibrinogen Variants Are Altered in Severe COVID-19
Background  Fibrinogen variants as a result of alternative messenger RNA splicing or protein degradation can affect fibrin(ogen) functions. The levels of these variants might be altered during coronavirus disease 2019 (COVID-19), potentially affecting disease severity or the thrombosis risk. Aim  To investigate the levels of fibrinogen variants in plasma of patients with COVID-19. Methods  In this case-control study, we measured levels of functional fibrinogen using the Clauss assay. Enzyme-linked immunosorbent assays were used to measure antigen levels of total, intact (nondegraded Aα chain), extended Aα chain (α E ), and γ' fibrinogen in healthy controls, patients with pneumococcal infection in the intensive care unit (ICU), ward patients with COVID-19, and ICU patients with COVID-19 (with and without thrombosis, two time points). Results  Healthy controls and ward patients with COVID-19 ( n  = 10) showed similar fibrinogen (variant) levels. ICU patients with COVID-19 who later did ( n  = 19) or did not develop thrombosis ( n  = 18) and ICU patients with pneumococcal infection ( n  = 6) had higher absolute levels of functional, total, intact, and α E fibrinogen than healthy controls ( n  = 7). The relative α E fibrinogen levels were higher in ICU patients with COVID-19 than in healthy controls, while relative γ' fibrinogen levels were lower. After diagnosis of thrombosis, only the functional fibrinogen levels were higher in ICU patients with COVID-19 and thrombosis than in those without, while no differences were observed in the other fibrinogen variants. Conclusion  Our results show that severe COVID-19 is associated with increased levels of α E fibrinogen and decreased relative levels of γ' fibrinogen, which may be a cause or consequence of severe disease, but this is not associated with the development of thrombosis.</p
Baseline characteristics of children in the early glasses study
Purpose: The relationship between refractive error at age 1 and the risk of developing amblyopia or accommodative esotropia, and the protection offered by early glasses, is unknown. These are determined in the Early Glasses Study, a prospective, population-based, longitudinal, randomized controlled study. We report baseline findings. Methods: Healthy children aged 12–18 months were recruited at Children’s Healthcare Centres (CHCs) and received an entry orthoptic examination followed by cycloplegic retinoscopy. Children with amblyopia, strabismus, ophthalmic disease or very high refractive error were excluded. Those exceeding the AAPOS 2003 Criteria (> + 3.5D spherical equivalent (SE), > 1.5D astigmatism, > 1.5D anisometropia) were randomized into wearing glasses or not, and are followed-up by research orthoptists. Other children are followed-up by regular vision screening at CHCs and visual acuity is measured in all children at age 4. Results: Parents of 865 children were called, 123 were excluded. Of 742 children enrolled, 601 underwent the entry orthoptic examination at age 14.5 ± 1.7 months. Mean SE was + 1.73 ± 1.18D, astigmatism -0.70 ± 0.44D, anisometropia 0.21D (IQR: 0–0.25). Of 62 (10.3%) children exceeding the Criteria, 52 were randomized into wearing glasses or not. Of 539 other children, 522 are followed up at CHCs. In total, 31 were excluded: 2 had strabismus and amblyopia, 7 strabismus, 2 amblyopia suspect, 1 strabismus suspect, 1 squinting during sinusitis, 4 excessive refractive error, 9 myopia, 2 ptosis, 1 oculomotor apraxia, 1 Duane syndrome, 1 congenital nystagmus. Conclusion: Prevalence of strabismus (10/601) was as expected, but prevalence of amblyopia (2/601) was low, suggesting that common amblyopia develops later than generally thought. Key messages : What is known • High refractive errors cause amblyopia, but no study has determined the exact relationship between the kind and size of refractive error at age 1 and the risk to develop amblyopia, and assessed the protective effect of glasses in a controlled, population-based, longitudinal study. What is new • At baseline, 601 children received a full orthoptic examination followed by retinoscopy in cycloplegia at the age of 14.5 ± 1.7 months; 10.3% had high refractive error exceeding spherical equivalent > + 3.5D, > 1.5D astigmatism, > 1D oblique astigmatism or > 1.5D anisometropia. • The prevalence of amblyopia was lower (0.3%) than expected, suggesting that most amblyopia develops after the first year of life. • The prevalence of anisometropia, associated with amblyopia in older children, was low (0.8%).</p
- …