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The urinary excretion of radiocopper in presymptomatic and symptomatic Wilson's disease, heterozygotes and controls: its significance in diagnosis and management.

Radiocopper (64Cu, 67CU), given intravenously, has been used to study the pattern of excretion of copper in patients with presymptomatic, symptomatic and treated Wilson's disease, together with heterozygotes for the Wilson's disease gene and a control group of patients with a variety of neurological lesions mimicking Wilson's disease. Urine was collected for three periods after injection, 0 to 8 hours, 8 to 24 hours, at which time a test dose of penicillamine was given, and from 24 to 30 hours. Stable (endogenous) copper was also estimated on these samples and specific activity was determined. This was multiplied by a correction factor to allow for variations in dose and body weight. The findings for stable copper in urine were largely predictable. Controls and heterozygotes had the least copper excretion, the amounts rising in the presymptomatic to a peak in the symptomatic patients. Institution of therapy was associated with a fall in copper excretion pro rata with time. The most important radiochemical findings were as follows. Heterozygotes excreted less of the injected copper than controls both under basal conditions and after penicillamine. Presymptomatic patients excreted less radiocopper than heterozygotes after penicillamine although the excretion during the basal 24 hour period was very much greater. Patients with symptomatic Wilson's disease had by far the highest excretion of radiocopper in all three time periods which fell after treatment, pro rata with time, as had been found for stable copper. These results were subjected to computer analysis. There was no overlap between the various groups with the exception of a single control subject who had combined pyramidal and extrapyramidal system degeneration of obscure aetiology. This patient was classified by the computer study as 'heterozygote'. These findings lend further support to the hypothesis that the loss of a single gene for copper balance can be detected with a high degree of accuracy and also that presymptomatic patients can be selected from a sibship for prophylactic treatment without the risk of subjecting healthy heterozygotes to unnecessary and potentially hazardous long-term therapy.

Adolescent

Presymptomatic diagnosis of adult onset polycystic kidney disease by ultrasonography.

Results of an ongoing prospective study of progeny of patients with adult-onset polycystic kidney disease using grey-scale ultrasound and high-dose nephrotomography are reported. Six asymptomatic subjects out of 17 at risk for polycystic kidney disease were found by ultrasonography to have multiple renal cysts; this included two unrelated children aged 18 months and 6 y who had normal high-dose nephrotomography. We suggest that ultrasonography may be the method of choice for presymptomatic detection of polycystic kidney disease. Serial studies of at-risk individuals by sonography will be useful in determining the earliest age of detection, the latest age of ultrasonography presentation, and in following the natural history of polycystic kidney disease.

Adolescent

Prognosis and possible presymptomatic manifestations of congestive cardiomyopathy (COCM).

In order to find evidence of prognosis and of presymptomatic manifestation of congestive cardiomyopathy (COCM) in fifty-eight patients, the extent of morphological changes of endomyocardial catheter biopsy (EMCB), clinical and haemodynamic data were correlated to the clinical course. In addition, clinical, haemodynamic, angiographic, morphological and His-bundle electrographic studies were performed in patients with left bundle branch block (LBBB), normal left ventricular end-diastolic volume, and normal coronary arteries (n = 43). Related to a 10-year mortality rate of 70% from the onset of symptoms, COCM is one of the most severe heart diseases. Endomyocardial catheter biopsy (EMCB) allowed clear prognostic separation in patients with COCM and seems to be of diagnostic value in patients with only slightly enlarged hearts and in patients with a short history of symptoms. The studies also revealed much evidence that at least some patients with LBBB, normal left ventricular end-diastolic volume (LVEDV) and normal coronary arteries exhibit an early stage of COCM. In these patients especially EMCB with severe changes of heart muscle cells and/or impaired left ventricular function may indicate subsequent COCM. So that there is now a new indication for performing EMCB.

Adult

Detection of presymptomatic carriers of Huntington's chorea.

Laterality of thumb opposition and handedness were determined in three groups of subjects: patients with Huntington's chorea (n = 18), asymptomatic offspring of patients (n = 40), and asymptomatic siblings of patients over 50 years of age termed 'escapees' (n = 17). 100% of patients and 55% of young at-risk offspring had crossed laterality of thumb opposition and handedness. Only 2 (11.8%) of the 'escapees' had crossed laterality. Crossed laterality may be associated with symptomatic presymptomatic Huntington's chorea.

Adolescent

Comprehensive cross-sectional and longitudinal comparisons of plasma glial fibrillary acidic protein and neurofilament light across FTD spectrum disorders.

BACKGROUND: Therapeutic development for frontotemporal dementia (FTD) is hindered by the lack of biomarkers that inform susceptibility/risk, prognosis, and the underlying causative pathology. Blood glial fibrillary acidic protein (GFAP) has garnered attention as a FTD biomarker. However, investigations of GFAP in FTD have been hampered by symptomatic and histopathologic heterogeneity and small cohort sizes contributing to inconsistent findings. Therefore, we evaluated plasma GFAP as a FTD biomarker and compared its performance to that of neurofilament light (NfL) protein, a leading FTD biomarker. METHODS: We availed ARTFL LEFFTDS Longitudinal Frontotemporal Lobar Degeneration (ALLFTD) study resources to conduct a comprehensive cross-sectional and longitudinal examination of the susceptibility/risk, prognostic, and predictive performance of GFAP and NfL in the largest series of well-characterized presymptomatic FTD mutation carriers and participants with sporadic or familial FTD syndromes. Utilizing single molecule array technology, we measured GFAP and NfL in plasma from 161 controls, 127 presymptomatic mutation carriers, 702 participants with a FTD syndrome, and 67 participants with mild behavioral and/or cognitive changes. We used multivariable linear regression and Cox proportional hazard models adjusted for co-variates to examine the biomarker utility of baseline GFAP and NfL concentrations or their rates of change. RESULTS: Compared to controls, GFAP and NfL were elevated in each FTD syndrome but GFAP, unlike NfL, poorly discriminated controls from participants with mild symptoms. Similarly, both baseline GFAP and NfL were higher in presymptomatic mutation carriers who later phenoconverted, but NfL better distinguished non-converters from phenoconverters. We additionally observed that GFAP and NfL were associated with disease severity indicators and survival, but NfL far outperformed GFAP. Nevertheless, we validated findings that the GFAP/NfL ratio may discriminate frontotemporal lobar degeneration with tau versus TDP-43 pathology. CONCLUSIONS: Our head-to-head comparison of plasma GFAP and NfL as biomarkers for FTD indicate that NfL consistently outmatched GFAP as a prognostic and predictive biomarker for participants with a FTD syndrome, and as a susceptibility/risk biomarker for people at genetic risk of FTD. Our findings underscore the need to include leading biomarkers in investigations evaluating new biomarkers if the field is to fully ascertain their performance and clinical value.

Humans

Proteomic analysis reveals distinct cerebrospinal fluid signatures across genetic frontotemporal dementia subtypes.

We used an untargeted mass spectrometric approach, tandem mass tag proteomics, for the identification of proteomic signatures in genetic frontotemporal dementia (FTD). A total of 238 cerebrospinal fluid (CSF) samples from the Genetic FTD Initiative were analyzed, including samples from 107 presymptomatic (44 C9orf72, 38 GRN, and 25 MAPT) and 55 symptomatic (27 C9orf72, 17 GRN, and 11 MAPT) mutation carriers as well as 76 mutation-negative controls ("noncarriers"). We found shared and distinct proteomic alterations in each genetic form of FTD. Among the proteins significantly altered in symptomatic mutation carriers compared with noncarriers, we found that a set of proteins including neuronal pentraxin 2 and fatty acid binding protein 3 changed across all three genetic forms of FTD and patients with Alzheimer's disease from previously published datasets. We observed differential changes in lysosomal proteins among symptomatic mutation carriers with marked abundance decreases in MAPT carriers but not other carriers. Further, we identified mutation-associated proteomic changes already evident in presymptomatic mutation carriers. Weighted gene coexpression network analysis combined with gene ontology annotation revealed clusters of proteins enriched in neurodegeneration and glial responses as well as synapse- or lysosome-related proteins indicating that these are the central biological processes affected in genetic FTD. These clusters correlated with measures of disease severity and were associated with cognitive decline. This study revealed distinct proteomic changes in the CSF of patients with genetic FTD, providing insights into the pathological processes involved in the disease. In addition, we identified proteins that warrant further exploration as diagnostic and prognostic biomarker candidates.

Humans

Precautions in familial transmissible dementia: including familial Alzheimer's disease.

Recent studies suggest that some cases of familial Alzheimer's disease may be associated with a transmissible dementia. Animal experiments show that presymptomatic carriers of "slow virus" agents can transmit disease. Because of these findings, we have extended the precautions previously delineated to include those at risk of acquiring transmissible dementia, specifically, to the descendants of those affected with familial Alzheimer's disease or familial Creutzfeldt-Jakob's disease. Blood donation from such persons may pose a danger, because transmissible spongioform encephalopathy has been passed from animal to animal by blood serum and by the WBC layer of frozen whole blood.

Alzheimer Disease

Quantitative temporal analysis of pancreatic islet T lymphocyte and macrophage infiltration heralded by serum IgE in congenic BioBreeding (BB) Gimap5-/- rats at risk for insulitis and acute onset diabetes.

OBJECTIVE AND DESIGN: The objective was to determine the association between serum IgE levels and the infiltration order of T lymphocytes and macrophages in pancreatic islets in relation to the loss of insulin and glucagon cells in presymptomatic congenic BB Gimap5-DP (Diabetes Prone) rats. MATERIAL: Congenic prediabetes BB Gimap5-DP and control Gimap5-DR (Diabetes Resistant) rats were followed every other day from 29 to 32 days of age until peak serum IgE (≤ 55 days of age). METHODS: Serum IgE was measured using ELISA. The HALO™ platform facilitated quantitative image analysis of infiltrating T lymphocytes, macrophages, and target organ insulin and glucagon cells. Whole genome sequencing (WGS) was employed to identify candidate type 1 diabetes genes. RESULTS: Serum IgE levels increased with age in normoglycemic BB Gimap5-DP rats. Quantification of infiltrating cells per mm2 in and around the islets indicated that T lymphocytes are the initial infiltrators, followed by macrophages. Elevated serum IgE levels inversely correlated with beta-cell mass (total mg insulin/mg pancreas). WGS refined the risk segment for islet inflammation to 1.02 Mbp, leaving 10 candidate genes, including Gimap4 and Gimap5. CONCLUSIONS: Elevated IgE levels herald T lymphocyte and macrophage infiltration. Pancreatic islet inflammation was linked to Gimap4, Gimap5, and other potential candidate genes on rat chromosome 4.

Animals

Next-generation newborn screening: feasibility of combined genetic and biochemical testing for 95 treatable inherited metabolic disorders.

INTRODUCTION: Next-generation sequencing (NGS) is gaining attention in newborn screening (NBS) for its ability to detect treatable genetic disorders, especially those without a biochemical footprint. However, NGS-NBS requires interpreting variants without phenotype information or family trio analysis. Biochemical tests, preferably in dried blood spots (DBS), are therefore useful to confirm the pathogenicity of variants identified by NGS-NBS and increase its specificity and sensitivity. OBJECTIVES: We aimed to explore the potential of combined genetic-biochemical testing for 95 treatable Inherited Metabolic Disorders (IMD) considered eligible for NGS-NBS (100 genes) previously identified by our research group. METHODS: We reviewed the Collaborative Laboratory Integrated Reports (CLIR) and carried out systematic literature reviews in PubMed and Embase to identify biochemical tests for 95 IMD. Biochemical tests conducted on DBS were differentiated from tests that require referral. RESULTS: We identified DBS-biochemical tests for 72 of the 95 IMD (77/100 genes). DBS-based biochemical tests for 55 IMD (60 genes) are already implemented in NBS. For the other 23 IMD, biochemical tests in non-DBS specimens are reported, although some are less sensitive when measured at neonatal age in presymptomatic infants. CONCLUSION: We present a comprehensive overview of current biochemical tests for 95 IMD. These tests can be used to confirm inconclusive NGS-NBS results, and combined genetic-biochemical testing is expected to improve both the negative and positive predictive values of NBS programs.

Humans

Parental Perspectives and Experiences with Genetic Testing and Surveillance for Cancer Predisposition in Healthy Young Children.

OBJECTIVES: To evaluate parental experiences following diagnosis of a cancer predisposition syndrome (CPS) in childhood and to assess parental perspectives on population-based genomic newborn screening (gNBS) for CPS. STUDY DESIGN: Participants were guardians of children diagnosed with a CPS by age 8, for whom cancer surveillance was recommended, and who had no history of cancer before the CPS diagnosis. Participants completed a demographic survey, genetic knowledge assessment, and a semistructured qualitative interview. Thematic analysis was performed on interview transcripts. Clinical data were abstracted from medical records. RESULTS: We enrolled 25 parents of children with 7 different CPS, including Li-Fraumeni syndrome (43%), familial adenomatous polyposis (14%), nevoid basal cell carcinoma syndrome (11%), and Beckwith-Wiedemann syndrome (11%). Parents characterized receiving a CPS diagnosis as emotionally challenging but also felt empowered by engagement in proactive cancer surveillance. They identified logistical, emotional, physical, and financial burdens of surveillance; however, most perceived that these burdens were outweighed by the medical and emotional advantages. The majority endorsed implementation of gNBS for pediatric cancer risk. CONCLUSIONS: Parents of presymptomatic children with a CPS experience both psychological distress and benefits following a genetic diagnosis. Despite the burdens of surveillance, parents express support for early genomic identification of cancer risk. These findings have implications for the care of children with CPS and inform implementation of population-based gNBS for CPS.

Humans

Respiratory pandemic risk in the Anthropocene: A One Health framework and GISRS+ agenda.

Recent epidemics and pandemics caused by respiratory viruses, alongside the animal panzootic spread of highly pathogenic avian influenza A(H5Nx), have become a structural feature of the Anthropocene, yet responses remain largely reactive. This review integrates findings from WHO's Global Influenza Surveillance and Response System (GISRS) and related surveillance data (2000-2024), epidemiological studies of influenza A virus, SARS-CoV, MERS-CoV, SARS-CoV-2, and H5Nx, and One Health literature. We examine major groups of respiratory viruses and identify mismatches between risk and surveillance by focusing on spillover potential from animal hosts, human-to-human transmission and its controllability, and Anthropocene characteristics that increase epidemic risk. The analysis indicated that SARS-related coronaviruses and influenza A viruses, particularly H5Nx, are among the leading candidates based on currently available evidence because they have large reservoirs in animal hosts and spillover to humans is highly probable. The previous presymptomatic spread of SARS-CoV-2 and recent mammalian adaptation in H5N1 clade 2.3.4.4b highlight limitations of the traditional symptom-based and pathogen-specific surveillance system. Spillover events tend to occur in tropical and subtropical regions in low- and middle-income countries, but most genomic surveillance is in high-income countries. We propose interventions that address the upstream, midstream, downstream processes of epidemics. Upstream interventions are primary prevention measures related to land use, livestock, wildlife, and urban environments; midstream interventions are GISRS+-based pathogen-agnostic genomic and metagenomic early warning systems triggered by One Health; and downstream interventions include vaccines, antivirals, non-pharmaceutical interventions, and engineering with equity-centred global governance and sustainable financing.

Anthropocene

Serum-25-hydroxy-vitamin-D in untreated parenchymal and cholestatic liver disease.

Serum-25-hydroxy-vitamin-D (25 OHD) concentration has been measured in 106 patients with untreated parenchymal and cholestatic liver disease. Low mean values were found in groups of patients with alcoholic hepatitis and cirrhosis, non-cirrhotic active chronic hepatitis, lupoid and cryptogenic cirrhosis, symptomatic primary biliary cirrhosis, and acute and chronic biliary disease. In a group of patients with presymptomatic biliary cirrhosis the mean value was not significantly different from normal. It is concluded that in the presence of significant parenchymal or cholestatic liver disease serum-25-OHD concentrations are usually low. The mechanisms for the reduction remain to be clarified, but low serum-25-OHD values may play a contributory role in the aetiology of osteomalacia in chronic liver disease.

Acute Disease

Impaired prolactin release in Huntington's chorea. Evidence for dopaminergic excess.

Eight individuals with Huntington's chorea had low basal and impaired human prolactin responses to both chlorpromazine and thyrotrophin-releasing hormone. These findings are compatible with enhanced hypothalamic dopaminergic activity in this disease. Two juvenile rigid patients with Huntington's chorea had excessive prolactin responses to chlorpromazine. Approximately half of the twenty-three potentially affected first-degree relatives of patients with Huntington's chorea had normal prolactin responses to chlorpromazine. However, twelve had significantly abnormal responses-seven in one direction, and five in the other. The predictive value of these findings in terms of presymptomatic diagnosis will be revealed by a longitudinal study. A biochemical method for the early recognition of the condition would have profound implications for genetic counselling.

Adolescent

A commentary on measles vaccine in the context of outbreaks: Viral evolution, waning immunity and public trust.

The measles vaccine, introduced over 60 y ago, has been proven to be both safe and effective. Despite the genetic diversity of the measles virus, eradication is considered possible with near-complete coverage of the two-dose vaccination schedule. However, real-world data show that this level of control has not yet been achieved. In addition to outbreaks among unvaccinated individuals, increasing numbers of measles cases are occurring among fully vaccinated, seropositive individuals. Both primary and secondary vaccine failures have been documented. Reduced vaccine effectiveness may occur in people with innate immune deficiencies, immunocompromised individuals (including those with HIV), and patients with chronic conditions such as diabetes. Furthermore, in regions without circulating wild-type virus, vaccine-induced antibody levels tend to decline over time and the impact of this may be more significant among infants. Emerging evidence highlights the importance of T lymphocyte - mediated immunity on effective B cell mediated immune response. Compounding the challenge, measles vaccination and infection are politicized, undermining public trust. Given the high transmissibility of measles, its potential for presymptomatic transmission, and the absence of specific early symptoms, complete eradication may not be feasible in the near term. Nevertheless, combining vaccine advocacy, transparent communication, and ongoing research will be critical to improving global vaccination strategies and public confidence.

Humans

Concepts in ectopic hormone production.

Non-endocrine tumours are capable of production of ectopic hormones, precursor molecules subunits and hormone-related fragments. The measurement of these may provide biochemical markers of malignancy, allowing presymptomatic diagnosis which may lead ultimately to an improved prognosis for the patient. The study of ectopic humoral syndromes may yield new insights into the nature of cellular differentation and the fundamental process of malignant change.

Adrenocorticotropic Hormone