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Background: Familial hypocalciuric hypercalcemia (FHH) is often due to inactivating variants in the calcium-sensing receptor (CASR) gene causing chronically elevated plasma calcium levels with inappropriately normal or elevated parathyroid hormone levels. In patients with primary hyperparathyroidism, the state of hyperparathyroid hypercalcemia is associated with reduced muscle strength and impaired quality of life (QoL). Objective: To study whether FHH affects muscle function, postural stability, and QoL. Design: In a cross-sectional study, we investigated muscle strength (handgrip, elbow flexion/extension, and knee flexion/extension), balance function, physical activity, and QoL in 50 patients with FHH and in a similar number of age- and gender-matched population-based healthy controls. All but one of the FHH cases had genetically verified inactivating variants in the CASR gene. Results: Studied subjects (n=100, 68% females) had a mean age of 56.0 years. Muscle strength as assessed by measuring maximum force and maximum force production did not differ between the groups. Neither did groups differ in terms of QoL, physical activity, or postural stability, as assessed during normal standing with eyes open, normal standing with eyes closed, semi-tandem standing, or tandem standing. Adjustment for vitamin D status (plasma 25-hydroxyvitamin D levels) and BMI did not change results. Conclusion: Despite a state of chronic hypercalcemia, muscle strength, balance function, and QoL are not impaired in patients with FHH. Our findings are reassuring for patients with FHH as they should not be considered as having a severe disease. [ABSTRACT FROM AUTHOR]

Familial hypercholesterolemia (FH) is a genetic disorder that may lead to premature coronary heart disease (CHD) and sudden cardiac death (SCD). Mutations in the LDLR or APOB genes cause FH. We have screened the LDLR and the ligand-binding region of APOB genes in 52 cases of SCD. Deceased patients were younger than 40 years of age and were suspected of having FH. The LDLR and APOB genes were examined via PCR, high-resolution melting, and DNA sequencing. Therein, it was observed that 7.7% of the screened patients exhibited a rare sequence variant in the LDLR gene, with 5.7% suspected of being pathogenic mutations. Lipid profiles and genetic testing for FH could be considered when autopsy reveals significant atherosclerosis of the coronary arteries in young adults. First-degree family members are advised to seek medical advice and testing to determine their own risks of atherosclerosis to prevent premature CHD and SCD. [ABSTRACT FROM AUTHOR]

Familial hypercholesterolemia (FH) is a genetic disorder that may lead to premature coronary heart disease (CHD) and sudden cardiac death (SCD). Mutations in the LDLR or APOB genes cause FH. We have screened the LDLR and the ligand-binding region of APOB genes in 52 cases of SCD. Deceased patients were younger than 40 years of age and were suspected of having FH. The LDLR and APOB genes were examined via PCR, high-resolution melting, and DNA sequencing. Therein, it was observed that 7.7% of the screened patients exhibited a rare sequence variant in the LDLR gene, with 5.7% suspected of being pathogenic mutations. Lipid profiles and genetic testing for FH could be considered when autopsy reveals significant atherosclerosis of the coronary arteries in young adults. First-degree family members are advised to seek medical advice and testing to determine their own risks of atherosclerosis to prevent premature CHD and SCD. [ABSTRACT FROM AUTHOR]

Three cDNA clones from a porcine small intestine cDNA library, tentatively identified as transcripts of two different cytochrome P450 (CYP) gene subfamilies, were sequenced and mapped. One of the clones was found to comprise an open reading frame of 503 amino acids and showed up to an 80% similarity to genes from the CYP3A subfamily. Translation of the other two cDNA clones revealed high similarity to genes from the CYP2C subfamily. One of these clones was truncated, lacking a part of the 5′ end of the coding region, whereas the other encodes a putative pseudogene. The CYP3A gene was mapped cytogenetically by means of a pig/rodent somatic hybrid cell panel to pig chromosome 3, in the region p16–p17 or p11. The CYP2C pseudogene was mapped genetically to pig chromosome 14, using the PiGMaP shared reference pedigrees. The localisations provide information for the human/pig comparative map. [ABSTRACT FROM AUTHOR]

It is common practice in laboratories to store biological samples in ultra-low temperature (ULT) freezers. There is growing interest in raising the temperature of ULT freezers in order to save energy and reduce expenses, as energy conservation becomes increasingly important and sustainable laboratory practices gain popularity. In our laboratory, plasma samples are stored for three months for diagnostic purposes. We therefore took the opportunity to investigate the effect of two different storage temperatures (-70 °C vs -80 °C), on activated partial thromboplastin time (APTT), factor VIII (FVIII), international normalized ratio (INR) and factor VII (FVII) measurements on paired plasma samples collected from 26 individuals after three months of storage. Automated coagulation analysers CS-5100 and ACL TOP were used to perform the tests. We found no consistent difference between the two storage temperatures for any of the four coagulation parameters (all p -values > 0.05). We conclude that the temperature of ULT freezers used to store plasma samples for APTT, FVIII, INR, and FVII measurements can be safely increased from -80 to -70 °C without affecting the stability of the samples.

Background: Reduced effect of antiplatelet therapy has been reported in patients with ST-segment elevation myocardial infarction (STEMI). Multiple factors may concur to explain this, including increased amount of highly reactive immature platelets., Objectives: To investigate the association between immature platelets and reactivity determined with multicolour flow cytometry using the SYTO-13 dye in STEMI patients., Methods: We conducted an observational study of 59 patients with acute STEMI. Blood samples were obtained within 24 h after admission and after loading doses of dual antiplatelet therapy. For comparison, samples were obtained from 50 healthy individuals. Immature platelets and platelet reactivity were investigated using multicolour flow cytometry including the SYTO-13 dye that binds to platelet RNA and thus provides a method for subdividing platelets into immature and mature platelets. Additionally, we assessed platelet aggregation, serum-thromboxane B 2 levels and standard immature platelet markers., Results: Immature platelets were more reactive than mature platelets in both STEMI patients and healthy individuals (p-values < 0.05). STEMI patients had lower platelet aggregation and thromboxane B 2 levels than healthy individuals. We found a positive association between automatically determined immature platelet markers and CD63 expression on activated platelets (Spearman's rho: 0.27 to 0.58, p-values < 0.05)., Conclusions: Our study shows that immature platelets identified with a multicolour flow cytometric method using the SYTO-13 dye are more reactive than mature platelets in patients with acute STEMI and in healthy individuals. The presence of immature platelets may be important for the overall platelet reactivity, which may have implications for the effect of antiplatelet therapy., Competing Interests: Declaration of competing interest None related to the present study. The authors report the following general conflict. ELG has received speaker honoraria or consultancy fees from AstraZeneca, Bayer, Boehringer Ingelheim, Bristol-Myers Squibb, Pfizer, Novo Nordisk, MSD, Lundbeck Pharma and Organon. He is investigator in clinical studies sponsored by AstraZeneca, Idorsia or Bayer and has received unrestricted research grants from Boehringer Ingelheim. AMH has received unrestricted research support from CSL Behring. SDK is coordinating national investigator in a clinical trial sponsored by Idorsia. OBP, PHN and LP have no conflicts to declare., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Introduction: The typical spatial pattern of amyloid-β (Aβ) in diagnosed Alzheimer's disease (AD) is that of a symmetrical hemispheric distribution. However, Aβ may be asymmetrically distributed in early stages of AD. Aβ distribution on PET has previously been explored in MCI and AD, but it has yet to be directly investigated in preclinical AD (pAD). We examined how Aβ was distributed in individuals with pAD and MCI using 11 C-Pittsburgh Compound B (PiB) PET., Methods: In this PET study, 79 subjects were retrospectively enrolled, including 34 controls, 24 pAD, and 21 MCI. All subjects underwent APOE genotyping, 11 C-PiB PET, MRI, and cognitive testing. We explored differences in Aβ load, Aβ lateralisation, and Aβ distribution, as well as associations between Aβ distribution and cognition., Results: The Aβ asymmetry index (AI) differed between groups, with pAD having the highest Aβ AI as compared to both controls and MCI. There was no clear Aβ lateralisation in pAD, but there was a non-significant trend towards Aβ being more left-lateralised in MCI. There were no correlations between the cognitive scores and Aβ AI or Aβ lateralisation in pAD or MCI., Conclusion: The distribution of Aβ is most asymmetrical in pAD, as Aβ first starts accumulating, and it then becomes less asymmetrical in MCI, when Aβ has spread further, suggesting that more pronounced asymmetrical Aβ distribution may be a distinguishing factor in pAD. Longitudinal studies examining the distribution of Aβ across the AD continuum are needed., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Author(s).)

Introduction: The risk of recurrent cardiovascular events in patients with coronary artery disease (CAD) is determined by multiple factors including platelet function and turnover. MicroRNAs (miRs) may regulate both platelet function and turnover. We aimed to identify candidate miRs associating with platelet function and turnover in a cohort of stable CAD patients. Furthermore, we retrieved information on binding targets of the candidate miRs to obtain a more comprehensive biological insight into miR regulation of platelet function and turnover., Methods: Based on existing literature and a pilot study, we identified nine candidate miRs. Subsequently, we investigated the expression of the candidate miRs in whole blood and their relation to platelet function and turnover in 749 CAD patients. Platelet function was analysed using impedance aggregometry, optical aggregometry and serum thromboxane B 2 measurements. Platelet turnover markers (immature platelet count, immature platelet fraction and mean platelet volume) were measured using monochromatic automated flow cytometry., Results: Expression of miR-93-5p, miR-126-3p, miR-150-5p, miR-423-3p and miR-1180-3p showed negative correlations with platelet function (p-values from <0.0001 to 0.0006, rho from -0.13 to -0.36). In addition, expression of miR-423-3p showed negative correlation with platelet turnover markers (p-values from 0.001 to 0.004, rho from -0.11 to -0.12)., Conclusions: We identified several novel miRs that may regulate platelet function and turnover, thereby contributing to the increased risk of recurrent cardiovascular events in CAD patients., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Background: Pazopanib can induce liver toxicity in patients with metastatic renal cell carcinoma (mRCC). We assessed the effect of a TA repeat polymorphism in the UGT1A1 (uridine diphosphate glucuronosyltransferase 1A1) gene encoding uridine diphosphate glucuronosyltransferase 1A1 on liver toxicity, dose reductions, and patient outcomes., Patients and Methods: Patients with mRCC treated with first-line pazopanib developing liver toxicity underwent genotyping for the UGT1A1 polymorphism. Liver toxicity was assessed using the Common Terminology Criteria for Adverse Events, version 4.0. Progression-free survival and overall survival were assessed using the Kaplan-Meier and log-rank methods., Results: Of 261 patients, 34 (13%) had developed liver toxicity after a median of 29 days (range, 5-155 days). Grade 4, 3, and 2 alanine aminotransferase or bilirubin had increased in 2 (6%), 17 (50%), and 8 (24%) patients, respectively. The UGT1A1 assessment demonstrated that 18 patients (53%) had TA6/TA7, 7 (21%) had TA7/TA7, and 9 (26%) had wild-type TA6/TA6. The UGT1A1 polymorphism was associated with improved median progression-free survival (TA6/TA6, 5.5 months; TA6/TA7, 34.2 months; TA7/TA7, 22.3 months; unknown UGT1A1 status, 9.2 months; UGT1A1 polymorphisms combined vs. unknown status, P = .021). UGT1A1 polymorphism was associated with improved median overall survival (TA6/TA6, 8.1 months, TA6/TA7 or TA7/TA7 not reached, unknown UGT1A1 status, 16.6 months; UGT1A1 polymorphisms combined vs. unknown status, P = .033). Patients with UGT1A1 polymorphism safely resumed pazopanib at ultra-low doses determined by the degree of liver toxicity and UGT1A1 polymorphism., Conclusions: UGT1A1 polymorphisms were associated with improved outcomes, despite pazopanib interruption and dose reductions. UGT1A1 assessment could improve the management of pazopanib-induced liver toxicity in patients with mRCC., (Copyright © 2019 The Author(s). Published by Elsevier Inc. All rights reserved.)

Introduction: Protein C deficiency is a heritable thrombophilia caused by numerous different genetic alterations in the protein C (PROC) gene. We aimed to identify variants causing protein C deficiency in a Danish population., Material and Methods: Sanger sequencing of the PROC gene was performed in 20 probands and 26 relatives. In total, 30participants were previously diagnosed with protein C deficiency. Protein C activity was measured by a chromogenic substrate method (N = 40) and antigen level by an enzyme-linked immunosorbent assay (N = 26)., Results: Ten different single nucleotide variants were detected in 13 probands (65%) and in seven of the relatives previously diagnosed with protein C deficiency. Five variants were novel. The median protein C activity level was lower in participants with an identified variant (50% (range: 38-75%)) than in protein C deficient participants without a variant (65% (range: 36-73%); P = 0.18). A protein C activity of 57% resulted in the highest detection rate (12/13 (92%)). Likewise, the median antigen level was lower in participants with detectable variants than in participants without (49% (range: 35-99%) vs 70% (range: 41-101%); P = 0.09). No difference was found in venous thromboembolism (VTE) prevalence comparing participants with (12/20 (60%)) and without (7/10 (70%)) a variant (P = 0.59)., Conclusion: In a Danish population, a PROC gene variant was identified in 67% of participants previously diagnosed with protein C deficiency. Five variants were novel. The study confirmed an association between biochemical severity and the presence of a PROC gene variant. The VTE risk did not seem to differ between protein C deficient participants with and without a variant., (Copyright © 2019. Published by Elsevier Ltd.)

Introduction: The diagnosis of sarcoidosis is challenging and involves radiological, clinical and paraclinical evaluation, the latter including the measurement of serum angiotensin-converting enzyme activity (s-ACE), which is elevated in about 60% of sarcoidosis patients. The normal inter-individual biological variation of s-ACE is large. Approximately 50% of the variation is due to a genomic insertion/deletion (I/D) polymorphism in the ACE gene., Methods: We searched the MEDLINE library for articles presenting genotype-based reference intervals for s-ACE in healthy people. We summarised the results as weighted mean DD/II ratios of s-ACE. We also summarised the presented frequencies of the genotypes., Results: We identified nine studies presenting genotype-based reference intervals. All studies found a significant difference between mean s-ACE in the three genotype groups DD, ID and II. The mean DD/II ratio was 1.85 (range: 1.79-1.92) for all studies, 2.01 (1.92-2.10) for Caucasians and 1.64 (1.55-1.73) for Asians. The median frequencies of genotypes among Caucasians were 23% II, 45% ID and 30% DD, and 45% II, 49% ID and 14% DD among Asians., Conclusion: Genotyping for the I/D polymorphism increases the benefit of s-ACE since all studies found significantly different levels between genotype groups in healthy subjects. Genotyping is of special value if s-ACE is between the upper 97.5 percentile for genotype II and DD since values in this interval are at risk of being misclassified. Due to assay variation, genotype-specific reference levels should be verified locally.

Purpose of Review: Hypercalcaemia is a potentially life-threatening condition. Familial hypocalciuric hypercalcaemia (FHH) is a rare, lifelong, benign condition. It is important to separate this condition from other hypercalcaemic states such as hypercalcaemia of malignancy and primary hyperparathyroidism (PHPT)., Recent Findings: FHH is caused by inactivating mutations in the calcium sensing receptor (CASR) gene leading to a general calcium-hyposensitivity, compensatory hypercalcaemia and hypocalciuria. The inheritance of FHH is autosomal dominant. Similar to PHPT, FHH is characterized by hypercalcaemia, unsuppressed or elevated plasma parathyroid hormone, and typically normal renal function. The phenotype is normal, and hypercalcaemic symptoms are generally absent. The hallmark is a relatively low urine calcium excretion in contrast to PHPT, in which urine calcium excretion is increased. The vitamin D status as measured by plasma 25-hydroxyvitamin D has been reported to be normal with normal seasonal variations, whereas plasma 1,25-dihydroxyvitamin D has been found slightly increased compared to normal. Bone mineral density Z-scores are normal in spite of a slightly increased bone turnover. Differential diagnoses include mainly PHPT, but in some cases also hypercalcaemia of malignancy and use of thiazide diuretics., Summary: In general, FHH does not require treatment. We recommend a two-step diagnostic procedure. First, the calcium/creatinine clearance ratio is measured from a 24-h urine. Second, all patients with calcium/creatinine clearance ratio of 0.020 or less are tested for mutations in the CASR gene. The diagnostic sensitivity of this setup is 98%.