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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

Single-nucleus profiling reveals a core disease signature and cell type-specific vulnerabilities in early Rett syndrome.

Rett syndrome (RTT) is an X-linked neurological disorder caused by MECP2 mutations, creating distinct cellular environments in females (mosaic) versus males (nonmosaic). Despite female patients representing most cases, how mosaicism contributes molecularly to RTT pathogenesis, particularly in presymptomatic stages, remains poorly understood. To address this question, we profiled hippocampal transcriptomes of young female and male RTT mice using bulk and single-nucleus RNA sequencing. We identified a core disease signature of consistently dysregulated genes only in MeCP2- cells across RTT models. Moreover, we uncovered non-cell autonomous effects exclusively in female MeCP2+ excitatory neurons, suggesting that these circuits are more vulnerable early in the mosaic RTT environment. The single-nuclei data also revealed an underappreciated MeCP2- interneuron subtype that had the most transcriptional dysregulation in both male and female RTT hippocampi. Together, these data highlight the different effects of MeCP2 loss on excitatory and inhibitory circuits between the mosaic and nonmosaic environments in early RTT pathogenesis.

Rett Syndrome

Cellular hypersensitivity to brain antigen in children of a family with hereditary ataxia.

Sensitisation to brain antigen was demonstrated in eight of 24 clinically normal first generation children in a family with hereditary ataxia. This ratio is consistent with that expected in a dominantly inherited condition. It suggests that immunological reactivity may precede the clinical expression of disease, with important implications for presymptomatic diagnosis and for pathogenesis of degenerative disease.

Adolescent

Sputum cytologic diagnosis of upper respiratory tract cancer.

Sputum cytologic testing has been applied in the screening of high-risk individuals for presymptomatic lung cancer. This same screening procedure sometimes identifies patients with upper respiratory tract cancers and thereby may permit earlier treatment. Patients enrolled in the Mayo Lung Project undergo sputum cytologic and chest roentgenographic screening at four-month intervals and are compared with matched controls who are not intensively screened. Experience to date indicates an incidence rate of approximately 1 per 1,000 per year of cancer in the upper respiratory and alimentary passages among males more than 45 years old who are heavy cigarette smokers. This compares with a rate of approximately 4 per 1,000 per year of lung cancer. Recognition of early cancer of the upper respiratory tract is an additional benefit of screening for lung cancer. Since cigarette smoking represents an etiologic agent common to both upper and lower respiratory tract cancers, tumors should be searched for in both sites in this high-risk population.

Aged

Systemic immune activation in hereditary cancer predisposition syndromes: a cross-sectional study.

BACKGROUND: Immune surveillance mechanisms contribute to the elimination of precancerous lesions in hereditary cancer predisposition syndromes (HCPSs). METHODS: By combining single-cell transcriptomics, multiparametric mass cytometry and cytokine profiling of the systemic immune environment in 391 individuals among whom 227 are living with HCPSs we investigated phenotypic alterations in cancer-free individuals with HCPS. RESULTS: A decrease in peripheral B cell abundance and their more differentiated phenotype have been confirmed both in breast cancer patients with germline pathogenic variants in BRCA1 (gpath(BRCA1)) and in patients living with Lynch syndrome (LS). Pre-cancer women with gpath(BRCA1) exhibited an activated phenotype of multiple immune cell lineages, similar to those with manifest disease. In LS, B cell phenotypes exhibited the largest changes in response to cancer eradication, while increased peripheral IL-6 levels was detected even in presymptomatic individuals with LS. CONCLUSIONS: HCPS-specific differences in the phenotype of the systemic immune system might be leveraged in future risk-reducing strategies.

Humans

Juvenile-onset metachromatic leukodystrophy: biochemical and electrophysiologic studies.

A 15-year-old girl with juvenile-onset metachromatic leukodystrophy (MLD) had markedly decreased leukocyte arylsulfatase A activity and low levels of leukocyte beta galactosidase and serum acid phosphatase. There was marked slowing of nerve condition velocity, and metachromasia was seen in biopsied sural nerve. Leukocyte arylsulfatase A activity was decreased in all members of the girl's family, and sural nerve action potentials were abnormal in two asymptomatic siblings. Electrophysiologic studies combined with biochemical studies may aid in the identification of presymptomatic metachromatic leukodystrophy homozygotes or asymptomatic heterozygotes.

Adolescent

ACG Clinical Guideline: Diagnosis and Management of Adenomatous Colorectal Polyposis Syndromes.

The hereditary adenomatous colorectal polyposis syndromes are incurable, systemic, cancer risk predisposition syndromes with substantial morbidity and mortality. They differ in their mode of inheritance, age at disease onset, phenotypic expression, and cancer risk. The most common cancer risks involve the gastrointestinal tract including the colon, rectum, duodenum, ampulla, and stomach. Identifying these syndromes through personal and family history risk assessment and germline genetic testing, along with timely surgical and endoscopic management, can reduce cancer incidence and mortality. These guidelines use the Grading of Recommendations, Assessment, Development, and Evaluation methodology to provide clinical guidance on the selection of individuals who should undergo a risk assessment for a hereditary adenomatous colorectal polyposis syndrome, modality and timing of germline genetic testing, cancer risk mitigation through endoscopic and surgical interventions, and the role of chemoprevention. This document reviews the approach to genetic testing in patients with phenotypic colorectal polyposis and the impact of presymptomatic diagnosis in families with a known familial germline pathogenic variant or clinical features suggestive of a hereditary adenomatous polyposis syndrome. Management strategies for patients based on genetic test results or without genetic testing are provided. We also review colorectal and extracolonic phenotypic benign and malignant manifestations of the known hereditary syndromes with a focus on the 2 most common hereditary colorectal polyposis syndromes: familial adenomatous polyposis and MUTYH-associated polyposis. The document concludes with recommendations on polyposis and cancer risk mitigation strategies and highlights updates to management since the previous guideline was published.

Humans

Levodopa.

Levodopa administered alone or in combination with a peripheral decarboxylase inhibitor is at present the best means available for the control of Parkinson symptoms. It has proved particularly effective in Parkinson's disease and postencephalitic parkinsonism. In these disorders its continued administration for periods that now exceed five years has resulted in sustained therapeutic responses and a significant decrease in mortality rate. Levodopa has been shown to be a safe pharmacologic agent even after long-term usage. However, its potential for inducing side effects makes it essential that patients be carefully screened before use and monitored throughout the period of administration. Though not fully established and lacking FDA approval at this time, levodopa appears to be useful in reversing the symptoms of hepatic encephalopathy and as a diagnostic aid in assessing pituitary disorders as well as uncovering presymptomatic Huntington's chorea.

Benserazide

Significance of ankle blood pressure in the diagnosis of peripheral vascular disease.

Lower extremity blood pressure, an accurate indicator of peripheral arterial disease and a sensitive means of evaluating therapy, is easily determined by the Doppler detector either at the bedside or in the physician's office. In conjunction with the exercise tolerance test and the ankle to arm ratio, it permits the physician to follow the course of the disease and assess the results of therapy. The test may also detect and determine the extent of presymptomatic arteriosclerosis obliterans when present in the opposite limb.

Aged

Computerised tomography in the leucodystrophies.

11 patients with a diagnosis of leucodystrophy are reported. In 9 the CAT scan was abnormal and showed areas of markedly decreased density in the white matter. 3 of these patients had adrenoleucodystrophy. In 2, contrast enhancement at the anterior borders of the low density areas was present. The 2 negative scans were from children with metachromatic leucodystrophy; one had an atypical form of the disease and the other had the biochemical defect, but was still presymptomatic and had no neurological deficit.

Adolescent

Pregnancy in Wilson's disease.

The effect of pregnancy has been studied in 10 mothers with Wilson's disease. Three were presymptomatic but had the typical biochemical lesion, two of these were receiving penicillamine treatment at the time of conception, the third had yet to be diagnosed. The remaining seven mothers had had symptoms of Wilson's disease and had been receiving treatment for periods ranging from two and a half to 19 years. These mothers had 15 pregnancies between them, 13 went to full term but two ended prematurely at 26 and 30 weeks. In only one did pregnancy have an unfavourable effect on the Wilson's disease; this mother had been on penicillamine for only two and a half years in a suboptimal dose because of drug induced thrombocytopoenia. In addition she had extensive oesophageal varices and pregnancy was complicated by toxaemia. The other nine patients remained well and two had three pregnancies each. On six occasions penicillamine was taken throughout pregnancy, but in seven it was discontinued from the sixth to the twelfth week. All 15 babies were normal but one died of extreme prematurity (26 weeks gestation). Pregnancy does not appear to be contraindicated in well treated Wilson's disease and penicillamine does not seem to pose an undue risk to the foetus.

Ceruloplasmin