非人灵长类动物模型睡眠研究在神经精神疾病的早期诊断和药效评价中的作用

清醒-睡眠的周期性调节需要众多单胺类神经递质(5-HT、NE、DA等)、乙酰胆碱等兴奋性神经递质以及GABA等抑制性神经递质的参与。这些递质系统的异常不仅会导致睡眠周期紊乱,还与一系列的精神性和神经退行性疾病相关。睡眠异常被认为是抑郁症、帕金森氏病等神经系统疾病发生的早期预警信号。相比起低等哺乳动物,非人灵长类动物的睡眠与人类的睡眠具有更好的可比性。近来,利用非人灵长类动物来建立神经精神疾病模型的研究已取得明显进展。在建模的同时监测动物的睡眠状况,有助于我们进一步了解睡眠在这些疾病早期诊断和发展过程中的作用,为疾病的早期诊断、治疗和药效评价提供更好的客观依据。     

Allergy and autoimmunity: Molecular diagnostics,therapy, and presumable pathogenesis

Allergic and autoimmune diseases represent immunopathological reactions of an organism to antigens. Despite that the allergy is a result of exaggerated immune response to foreign antigens (allergens) and autoimmune diseases are characterized by the pathological response to internal antigens (autoantigens), the underlying mechanisms of these diseases are probably common. Thus, both types of diseases represent variations in the hypersensitivity reaction. A large percentage of both the adult and pediatric population is in need of early diagnostics of these pathologies of the immune system. Considering the diversity of antibodies produced in allergic and autoimmune disease and the difficulties accompanying clinical diagnosing, molecular diagnostics of these pathological processes should be carried out in several stages, including screening and confirmatory studies. In this review, we summarize the available data on the molecular diagnostics and therapy of allergic and autoimmune diseases and discuss the basic similarities and differences in the mechanisms of their development.     

Early epidemic spread,percolation and Covid-19

Journal of Mathematical Biology - Human to human transmissible infectious diseases spread in a population using human interactions as its transmission vector. The early stages of such an outbreak...     

Diagnosing prion diseases: needs, challenges and hopes

Prion diseases are among the most intriguing infectious diseases and are associated with unconventional proteinaceous infectious agents known as prions. Prions seem to lack nucleic acid and propagate by transmission of protein misfolding. The nature of prions and their unique mode of transmission present challenges for early diagnosis of prion diseases. In this article, state-of-the-art prion diagnostic techniques, together with the new strategies that are being used to develop sensitive, early and non-invasive diagnoses for these diseases are reviewed.     

Mitochondrial dysfunction, oxidative stress, regulation of exocytosis and their relevance to neurodegenerative diseases

A common feature in the early stages of many neurodegenerative diseases lies in mitochondrial dysfunction, oxidative stress, and reduced levels of synaptic transmission. Many genes associated with neurodegenerative diseases are now known to regulate either mitochondrial function, redox state, or the exocytosis of neurotransmitters. Mitochondria are the primary source of reactive oxygen species and ATP and control apoptosis. Mitochondria are concentrated in synapses and significant alterations to synaptic mitochondrial localization, number, morphology, or function can be detrimental to synaptic transmission. Mitochondrial by-products are capable of regulating various steps of neurotransmission and mitochondrial dysfunction and oxidative stress occur in the early stages of many neurodegenerative diseases. This mini-review will highlight the prospect that mitochondria regulates synaptic exocytosis by controlling synaptic ATP and reactive oxygen species levels and that dysfunctional exocytosis caused by mitochondrial abnormalities may be a common underlying phenomenon in the initial stages of some human neurodegenerative diseases.     

Antagonistic pleiotropy,mutation accumulation,and human genetic disease

The antagonistic pleiotropy theory of senescence is the most convincing theoretical explanation of the existence of aging. As yet, no locus or allele has been identified in a wild population with the features predicted by the pleiotropic theory. Human genetic diseases offer the opportunity to identify potentially pleiotropic alleles/loci. Four human genetic diseases—Huntington's disease, idiopathic hemochromatosis, myotonic dystrophy, and Alzheimer's disease—may exhibit pleiotropic effects and further study of these diseases might result in the identification of pleiotropic genes causing aging. Inability to find an early life selective benefit associated with these disease-causing alleles would favor the major alternative genetic explanation for aging, the mutation accumulation theory.     

Free radical processes in aging, neurodegenerative diseases and other pathological states

Literature data on the role of oxidative stress in aging have been summarized. There are certain links between parameters of free radical processes (intensity of generation of reactive oxygen species in mitochondria, oxidative modification of mitochondrial DNA, activity of desaturases, involved into biosynthesis of polyunsaturated C₂₀ and C₂₂ fatty acids) with life span. The review highlights the role of oxidative stress as on of pathogenic factors of numerous diseases including various neurodegenerative disorders. Special attention is paid to oxidative modification of proteins as one of early and reliable markers of tissue injury in free radical pathology. Oxidative destruction of proteins plays a major role in etiology of such neurodegenerative diseases as Alzheimer’s and Parkinson’s diseases. Oxidative stress and the stress related protein aggregation are considered as the pathogenic link in the development of familiar amyotrophic lateral sclerosis. Oxidative modification of proteins is associated with the development of cataract. The age-and pathology-related increases in the content of oxidized proteins in tissues is assessed as an early and specific parameter of oxidative stress.     

The hydrocephalus inducing gene product, Hydin, positions axonemal central pair microtubules

Background  

Impairment of cilia and flagella function underlies a growing number of human genetic diseases. Mutations in hydin in hy3 mice cause lethal communicating hydrocephalus with early onset. Hydin was recently identified as an axonemal protein; however, its function is as yet unknown.     

A comparative study of alteration in lymphocyte subsets among varicella, hand-foot-and-mouth disease, scarlet fever, measles, and Kawasaki disease

Changes in the lymphocyte subsets of 13 patients with varicella, 5 with hand-foot-and-mouth disease, 4 with scarlet fever, 10 with measles and 20 with Kawasaki disease were examined by immunofluorescent flow cytometric analysis using monoclonal antibodies against lymphocyte cell surface antigens. The results were compared with those of age-matched normal controls. A significant increase in the percentage of Leu-2a positive (Leu-2a+) cells was shown during the early convalescence of varicella, scarlet fever and measles. A significant decrease in the percentage of Leu-3a+ cells during the acute phase was common to all the diseases examined, and a significant decrease of Leu-4+ cells was observed except in measles. As a result, a significant decrease in the Leu-3a+/Leu-2a+ ratio was common to all the diseases examined during the acute and/or early convalescent phases. Leu-M3+ cells increased significantly in varicella, scarlet fever, and Kawasaki disease. HLA-DR+ cells increased significantly in varicella and Kawasaki disease. No significant changes in the proportions of Leu-7+, Leu-10+, and 2H7+ cells were found throughout the course of all the diseases examined.     

Obesity,diabetes mellitus,and pancreatic carcinogenesis: Correlations,prevention, and diagnostic implications

The prevalence of obesity, diabetes mellitus (DM), and pancreatic cancer (PC) has been consistently increasing in the last two decades worldwide. Sharing various influential risk factors in genetics and environmental inducers in pathogenesis, the close correlations of these three diseases have been demonstrated in plenty of clinical studies using multiple parameters among different populations. On the contrary, most measures aimed to manage and treat obesity and DM effectively reduce the risk and prevent PC occurrence, yet certain drugs can inversely promote pancreatic carcinogenesis instead. Most importantly, an elevation of blood glucose with or without a reduction in body weight, along with other potential tools, may provide valuable clues for detecting PC at an early stage in patients with obesity and DM, favoring a timely intervention and prolonging survival. Herein, the epidemiological and etiological correlations among these three diseases and the supporting clinical evidence of their connections are first summarized to favor a better and more thorough understanding of obesity- and DM-related pancreatic carcinogenesis. After comparing the distinct impacts of different weight-lowering and anti-diabetic treatments on the risk of PC, the possible diagnostic implications of hyperglycemia and weight loss in PC screening are also addressed in detail.     

Misfolded protein aggregates: mechanisms, structures and potential for disease transmission

Some of the most prevalent human degenerative diseases appear as a result of the misfolding and aggregation of proteins. Compelling evidence suggest that misfolded protein aggregates play an important role in cell dysfunction and tissue damage, leading to the disease. Prion protein (Prion diseases), amyloid-beta (Alzheimer's disease), alpha-synuclein (Parkinson's disease), Huntingtin (Huntington's disease), serum amyloid A (AA amyloidosis) and islet amyloid polypeptide (type 2 diabetes) are some of the proteins that trigger disease when they get misfolded. The recent understanding of the crucial role of misfolded proteins as well as the structural requirements and mechanism of protein misfolding have raised the possibility that these diseases may be transmissible by self-propagation of the protein misfolding process in a similar way as the infamous prions transmit prion diseases. Future research in this field should aim to clarify this possibility and translate the knowledge of the basic disease mechanisms into development of novel strategies for early diagnosis and efficient treatment.     

Sex-biased chromatin and regulatory cross-talk between sex chromosomes,autosomes, and mitochondria

Several autoimmune and neurological diseases exhibit a sex bias, but discerning the causes and mechanisms of these biases has been challenging. Sex differences begin to manifest themselves in early embryonic development, and gonadal differentiation further bifurcates the male and female phenotypes. Even at this early stage, however, there is evidence that males and females respond to environmental stimuli differently, and the divergent phenotypic responses may have consequences later in life. The effect of prenatal nutrient restriction illustrates this point, as adult women exposed to prenatal restrictions exhibited increased risk factors of cardiovascular disease, while men exposed to the same condition did not. Recent research has examined the roles of sex-specific genes, hormones, chromosomes, and the interactions among them in mediating sex-biased phenotypes. Such research has identified testosterone, for example, as a possible protective agent against autoimmune disorders and an XX chromosome complement as a susceptibility factor in murine models of lupus and multiple sclerosis. Sex-biased chromatin is an additional and likely important component. Research suggesting a role for X and Y chromosome heterochromatin in regulating epigenetic states of autosomes has highlighted unorthodox mechanisms of gene regulation. The crosstalk between the Y chromosomes and autosomes may be further mediated by the mitochondria. The organelles have solely maternal transmission and exert differential effects on males and females. Altogether, research supports the notion that the interaction between sex-biased elements might exert novel regulatory functions in the genome and contribute to sex-specific susceptibilities to autoimmune and neurological diseases.     

Epidemiology,risk factors,and lifestyle modifications for gout

Gout affects more than 1% of adults in the USA, and it is the most common form of inflammatory arthritis among men. Accumulating data support an increase in the prevalence of gout that is potentially attributable to recent shifts in diet and lifestyle, improved medical care, and increased longevity. There are both nonmodifiable and modifiable risk factors for hyperuricemia and gout. Nonmodifiable risk factors include age and sex. Gout prevalence increases in direct association with age; the increased longevity of populations in industrialized nations may contribute to a higher prevalence of gout through the disorder's association with aging-related diseases such as metabolic syndrome and hypertension, and treatments for these diseases such as thiazide diuretics for hypertension. Although gout is considered to be primarily a male disease, there is a more equal sex distribution among elderly patients. Modifiable risk factors for gout include obesity, the use of certain medications, high purine intake, and consumption of purine-rich alcoholic beverages. The increasing prevalence of gout worldwide indicates that there is an urgent need for improved efforts to identify patients with hyperuricemia early in the disease process, before the clinical manifestations of gout become apparent.     

Non-invasive, ultra-sensitive, high-throughput assays to quantify rare biomarkers in the blood

Many diseases are easier to treat and control when detected at an early stage of disease progression. Often, disease-related antigens or biomarkers are shed from the primary site and present in the blood. Unfortunately, there are very few tests capable of detecting these rare biomarkers in the blood. A blood test would be very useful to diagnose the disease earlier, monitor effectiveness of treatments, predict recurrence, and monitor recurrence. There is certainly a need to develop assays that are ultra-sensitive, non-invasive, and high-throughput. Here we describe several highly sensitive immunological assays we have developed to detect rare serum antigens. Initially we created an assay named immuno-detection amplified by T7 RNA polymerase (IDAT). To enhance the effectiveness and streamline the procedure, this assay was amended to the facile amplification system termed fluorescent amplification catalyzed by T7 polymerase technique (FACTT). These assays have been used to analyze the tumor antigen HER2 and the prion protein PrPSc. They can also be applied to other tumor markers or antigens from a variety of diseases such as cardiovascular disease, rheumatoid arthritis, Alzheimer's disease, Parkinson's disease, and hepatitis. These tests are not limited to testing only serum, but may also be applicable to detecting biomarkers in tissue, saliva, urine, cerebrospinal fluid, etc. Clearly, the FACTT-based technology represents an important step in the detection of rare molecules in fluids or tissues for a variety of diseases.     

T cell subset patterns that predict resistance to spontaneous lymphoma,mammary adenocarcinoma,and fibrosarcoma in mice

Aging leads to changes in the proportion of several T cell subsets in peripheral blood, but it is not yet known whether these changes have prognostic significance for late-life diseases. To examine this question, levels of T cell subsets were measured at 8 and 18 mo of age in the peripheral blood of mice of a genetically heterogeneous stock, and the mice were then subsequently evaluated for life span and for cause of death. The results indicate that mice whose T cell subset patterns look like those of old mice tend to die at earlier ages, regardless of the specific cause of death. At 18 mo, 39% of the variance within the set of seven measured subsets could be combined statistically into a single number, whose correlation with individual subsets suggested that it could be interpreted as an index of immunological aging. T cell subset pattern, as represented by this index, was a predictor of life span in mice dying of lymphoma, fibrosarcoma, mammary adenocarcinoma, or of all other causes considered together. Even as early as 8 mo of age, T cell subset patterns are significant predictors of all three forms of cancer, although at this age the association is stronger in mated female mice than in virgin mice. These results support two controversial hypotheses, which are not mutually exclusive: 1) early immune senescence might predispose to early death from cancer and 2) differences in aging rate, as monitored by tests of immune status, might accelerate or decelerate a wide range of late life neoplastic diseases.     

Antibodies reacting to mimotopes of Simian virus 40 large T antigen,the viral oncoprotein,in sera from children

Recent data indicate that the Simian virus 40 (SV40) infection appears to be transmitted in humans independently from early SV40-contaminated antipolio vaccines. Serum antibodies against SV40 large T antigen (Tag) were analyzed in children/adolescents and young adults. To investigate antibodies reacting to SV40 Tag antigens, serum samples ( n = 812) from children and young adults were analyzed by indirect ELISAs using specific SV40 Tag mimotopes. Mimotopes were synthetic peptides corresponding to SV40 Tag epitopes. In sera ( n = 412) from healthy children up to 17 years old, IgG antibodies against SV40 Tag mimotopes reached an overall prevalence of 15%. IgM antibodies against SV40 Tag were detected in sera of children 6–8 months old confirming and extending the knowledge that SV40 seroconversion occurs early in life. In children/adolescents affected by different diseases ( n = 180) SV40 Tag had a prevalence of 18%, being the difference no significant compared to healthy subjects ( n = 220; 16%) of the same age. Our immunological data indicate that SV40 circulates in children and young adults, both in healthy conditions and affected by distinct diseases. The IgM detection in sera from healthy children suggests that the SV40 infection/seroconversion occurs early in life (>6 months). Our immunological data support the hypothesis that SV40, or a closely related still unknown polyomavirus, infects humans. The SV40 seroprevalence is lower than common polyomaviruses, such as BKPyV and JCPyV, and other new human polyomaviruses. In addition, our immunological surveillance indicates a lack of association between different diseases, considered herein, and SV40.     

S100A1, a new marker for acute myocardial ischemia

The Ca(2+)-binding S100A1 protein displays a specific and differential expression in the human myocardium and is considered to be an important regulator of heart function. Because of its high expression levels in the heart we tested the performance of S100A1 as a diagnostic indicator of acute myocardial damage. Therefore, we established a S100A1-specific sandwich ELISA and determined the S100A1 plasma levels in patients with signs of acute myocardial ischemia. The concentration-time course of S100A1 was distinct from that of the "classical" biochemical markers, CK, CKMB, and troponin I, showing an early rise and a fast decline in plasma after the ischemic event. We suggest that S100A1 should be included in combinatorial measurements as an early diagnostic marker for ischemic coronary diseases.     

DNA repair fidelity in stem cell maintenance,health, and disease

Stem cells are a sub population of cell types that form the foundation of our body, and have the potential to replicate, replenish and repair limitlessly to maintain the tissue and organ homeostasis. Increased lifetime and frequent replication set them vulnerable for both exogenous and endogenous agents-induced DNA damage compared to normal cells. To counter these damages and preserve genetic information, stem cells have evolved with various DNA damage response and repair mechanisms. Furthermore, upon experiencing irreparable DNA damage, stem cells mostly prefer early senescence or apoptosis to avoid the accumulation of damages. However, the failure of these mechanisms leads to various diseases, including cancer. Especially, given the importance of stem cells in early development, DNA repair deficiency in stem cells leads to various disabilities like developmental delay, premature aging, sensitivity to DNA damaging agents, degenerative diseases, etc. In this review, we have summarized the recent update about how DNA repair mechanisms are regulated in stem cells and their association with disease progression and pathogenesis.     

Role of the immediate early response 3 (IER3) gene in cellular stress response, inflammation and tumorigenesis

The expression of the early response gene immediate early response 3 (IER3), formerly known as IEX-1, is induced by a great variety of stimuli, such as growth factors, cytokines, ionizing radiation, viral infection and other types of cellular stress. Being of a rather unique protein structure not sharing any similarity to other vertebrate proteins, IER3 plays a complex and to some extent contradictory role in cell cycle control and apoptosis. As outlined in this review, these effects of IER3 relate to an interference with certain signalling pathways, in particular NF-κB, MAPK/ERK and PI3K/Akt. In addition to numerous functional data relying on cell culture based studies, transgenic and knock-out mouse models revealed an involvement of IER3 expression in immune functions and in the physiology of the cardiovascular system. Deficiency of IER3 expression in mice results in an aberrant immune regulation and enhanced inflammation, in an alteration of blood pressure control and hypertension or in an impaired genomic stability. A number of patient related studies revealed an involvement of IER3 in tumorigenesis in a cell-type dependent but not yet understood manner. Future studies should establish the potential of IER3 as a new predictive marker and as a molecular target in human diseases such as cancer, inflammatory diseases or hypertension.