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Predicted brain-regional gene expression patterns in individuals living with Alzheimer's disease.

Studying brain gene expression in Alzheimer's Disease (AD) remains difficult as postmortem brain is difficult to access, cannot be used to guide donor treatment, may be confounded by environmental factors before and after death, and is difficult to link to early AD states or disease progression. To circumvent these limitations, several studies have tested blood transcriptome biomarkers for AD. However, gene-expression levels in the blood have limited correlation with those in the brain. To evaluate the potential of monitoring Alzheimer's progression with peripheral data, we used transcriptome-imputation to identify brain-region-specific AD-associated gene-expression differences in cohorts with blood-based transcriptome data. This approach provides a high-resolution image of AD-associated molecular differences in the brains of individuals actively living with disease. We analyzed eight AD studies (777 AD cases, 779 cognitively unimpaired controls), imputing transcriptomes in 10 brain regions via the Brain Gene Expression and Network Imputation Engine (BrainGENIE). Hundreds of differentially expressed genes (DEGs) associated with AD were identified in nine brain regions, with anterior cingulate cortex and amygdala showing the most differential expression. AD-associated genes were enriched in pathways such as proteostasis, mitochondrial dysfunction, and immune activation. We observed significant yet moderate concordance between imputed AD-associated changes and those directly measured in the dorsolateral prefrontal cortex and cerebellum. These transcriptomic changes can guide future in vitro studies focused on pathogenesis or be targets of novel therapeutic development. In conclusion, we demonstrated the scope and utility of brain expression imputation from the peripheral transcriptome, laying the groundwork for biomarker discovery and prospective AD studies.

Alzheimer Disease↗

The role of the brain-bone axis in skeletal degenerative diseases and psychiatric disorders, A genome-wide pleiotropic analysis.

INTRODUCTION: Skeletal degenerative diseases and psychiatric disorders often coexist clinically. However, the genetic correlations and underlying biological mechanisms between these two types of diseases remain unclear. OBJECTIVES: To investigate the genetic correlations between skeletal degenerative diseases and psychiatric disorders and to identify shared genomic loci, genes, and pathways. METHODS: This comprehensive genome-wide pleiotropic association study utilized summary statistics from publicly available genome-wide association data. Various statistical genetic correlation methods were employed, including LDSC, HDL, PLACO, Coloc, Hyprcoloc, and Mendelian randomization (MR) analysis, along with immune cell colocalization analysis. The study aimed to identify potential shared genetic factors among three skeletal degenerative diseases (osteoarthritis, intervertebral disc degeneration, and osteoporosis) and three psychiatric disorders (schizophrenia, anxiety disorder, and major depressive disorder). RESULTS: Analyses using LDSC, HDL, and Bonferroni corrections revealed significant genetic correlations between intervertebral disc degeneration (IVDD) and anxiety disorder (ANX); fractures, IVDD, and arthritis with major depressive disorder (MDD); and arthritis with schizophrenia (SCZ). Significant genetic correlations were also observed between VDD and ANX, fractures, IVDD, hip osteoarthritis (HipOA), knee osteoarthritis (KneeOA) and MDD, and KneeOA and SCZ. Pleiotropy analysis using PLACO, MAGMA, and multitrait colocalization Hyprcoloc identified 65 pleiotropic loci, 27 shared causal loci, and 9 shared risk loci involving immune cells related to both psychiatric and bone-related diseases. Additionally, tissue-specific enrichment analysis showed that genes mapped to these loci were enriched in brain, cardiovascular, pancreatic, and other tissues. The IVW method demonstrated that MDD increased the risk of IVDD and KneeOA, while IVDD increased the risk of ANX and MDD. Conversely, SCZ was associated with a reduced risk of KneeOA. Multiple sensitivity analyses further supported a positive causal effect of IVDD on MDD. CONCLUSION: These findings suggest significant genetic correlations between skeletal degenerative diseases and psychiatric disorders, highlighting multiple shared comorbid genes and key immune cell types. Importantly, the study supports the role of the brain-bone axis in the regulation of skeletal degenerative diseases and psychiatric disorders, which could provide valuable insights for potential therapeutic targets and interventions for these conditions.

Humans↗

Increased levels of serum soluble L-selectin in unmedicated patients with schizophrenia.

OBJECTIVE: Numerous studies have linked schizophrenia with altered immune function. The selectin family of adhesion molecules plays a prominent role in immune/inflammatory responses. To further study the immunological processes in the pathophysiology of schizophrenia, we determined the serum levels of selectins in patients with schizophrenia. For specificity, we also investigated selectin levels in patients with major depression. METHOD: We studied 23 unmedicated patients with schizophrenia, 17 unmedicated patients with major depression, and 36 healthy subjects. The serum levels of three types of soluble-form selectin (sE-, sL- and sP-selectin) were determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: Serum sL-selectin levels were significantly higher in patients with schizophrenia than in either control subjects (p=0.005) or patients with major depression (p=0.02). No significant difference was found with regard to the level of either serum sE-selectin or sP-selectin. CONCLUSION: Elevated sL-selectin levels in patients with schizophrenia may represent immune system dysfunction and may be involved in the pathogenesis of the illness.

Adult↗

Loss of peritubular capillaries in the development of chronic allograft nephropathy.

BACKGROUND: Chronic allograft nephropathy (CAN) remains the most important cause of late renal graft loss. In this study, we examined the role of peritubular capillary (PTC) injury in the development of CAN. METHODS: We studied renal biopsies (n = 79) obtained from grafts with CAN. PTC injury was examined morphologically by immunohistochemistry for CD34. These findings were correlated with interstitial fibrosis and graft dysfunction. Humoral immunity involved in CAN was studied by C4d staining. RESULTS: The CAN cases in the present study included chronic rejection (CR) (n = 14, 17.8%) and C4d-positive chronic humoral rejection (CHR; n = 6, 42.9% in CR cases). Irrespective of CR, CHR, or other CAN, the development of CAN was characterized by injury to and loss of identifiable PTCs, accompanied with the development of interstitial fibrosis. In CR and CHR cases, the loss of PTCs was prominent and seemed to progress within a relatively short period after transplantation. A decrease in the number of PTCs significantly correlated with the development of interstitial fibrosis (r = -0.75, P < .001) and impairment of graft function (r = -0.69, P < .001). CONCLUSIONS: Irrespective of whether CR, CHR, or other factors contribute to CAN, the processes involved in its development appear similar and are characterized by progressive injury and loss of PTCs, with the development of renal scarring. Immunohistochemistry for CD34 in human renal biopsies is a useful method for the detection of microvascular injury.

Antibody Formation↗

Morphine suppresses lymphocyte apoptosis by blocking p53-mediated death signaling.

Opiates such as morphine or heroin may promote cell apoptosis and cause dysfunction of immune cells. In simian immunodeficiency virus (SIV)-infected lymphocytic cells, however, morphine may protect the cells from apoptotic lysis and allow the virus to continue to replicate. To further explore this apparently antithetical effect of opiates, we evaluated in the present study the effects of morphine on human lymphocytic CEM x174 cells induced to undergo apoptosis in the presence of actinomycin D. It was found that induction of apoptosis (characterized by DNA laddering) by actinomycin D was accompanied by a stimulation of the expression of active (phosphorylated) form of p53. Pretreatment of the cells with 10nM morphine caused a transient, naloxone-reversible suppression of the appearance of activated p53 and the generation of DNA laddering. Parallel evaluation of the growth of CEM x174 indicated that morphine treatment delays the inception of cell death triggered by actinomycin D. Inasmuch as Bcl-2 suppresses while Bax accelerates apoptosis, treatment of cells with morphine reduced the expression of Bax and enhanced the expression of Bcl-2. Taken together, morphine, through binding at the opioid receptor, may protect lymphocytic cells from apoptotic lysis if cell death is initiated by apoptosis-inducing agents such as human immunodeficiency virus (HIV), SIV or actinomycin D.

Analgesics, Opioid↗

Illness perceptions and levels of disability in patients with chronic fatigue syndrome and rheumatoid arthritis.

OBJECTIVE: To investigate the strength of chronic fatigue syndrome (CFS) patients' negative illness perceptions by comparing illness perceptions and self-reported disability in patients with CFS and rheumatoid arthritis (RA). METHODS: Seventy-four RA patients and 49 CFS patients completed the Illness Perception Questionnaire-Revised and the 36-item Short-Form Health Survey. RESULTS: When compared to the RA group, the CFS group attributed a wider range of everyday somatic symptoms to their illness, perceived the consequences of their illness to be more profound and were more likely to attribute their illness to a virus or immune system dysfunction. Both groups reported equivalent levels of physical disability but the CFS group reported significantly higher levels of role and social disability. CONCLUSION: Although the symptoms of CFS are largely medically unexplained, CFS patients have more negative views about their symptoms and the impact that these have had on their lives than do patients with a clearly defined and potentially disabling medical condition. The data support the cognitive behavioural models of CFS that emphasise the importance of patients' illness perceptions in perpetuating this disorder.

Adult↗

Single dose levofloxacin prophylaxis for prostate biopsy in patients at low risk.

PURPOSE: We determine if a single 500 mg. oral tablet of levofloxacin represents adequate prophylaxis for patients at low risk who undergo transrectal prostate biopsy. MATERIALS AND METHODS: From April 2000 to May 2001 we prospectively evaluated 400 consecutive men who underwent transrectal needle biopsy of the prostate after a single 500 mg. oral dose of levofloxacin. Under an institutional review board approved protocol the drug was issued under a standing order by a clinic nurse 30 to 60 minutes before the procedure. Patients were issued 2 additional daily doses of levofloxacin if they were deemed at increased risk for infectious complications, that is if they had a large prostate more than 75 cc, diabetes mellitus, recent steroid use, severe voiding dysfunction or immune compromise. No patient received a cleansing enema before the procedure. Complications, the number of biopsy cores, prostate size and cancer detection rates were assessed. RESULTS: Only 1 of the 377 patients at low risk in whom biopsy was completed experienced a symptomatic urinary tract infection (0.27%). None of the 23 men at high risk who received additional doses of levofloxacin experienced a complication. Thus, the overall infection rate was 1 of 400 cases (0.25%) in this series. A mean of 7 biopsy cores (range 2 to 16) was obtained per patient and mean prostate volume was 49.75 cc (range 12 to 150). Prostate cancer was present in 93 patients (23%). CONCLUSIONS: A single 500 mg. dose of levofloxacin before transrectal needle biopsy of the prostate is effective and safe in patients at low risk. The administration of prophylaxis by a clinic nurse under a standing order optimizes patient compliance and physician efficiency. In patients at higher risk for infection additional antibiotic administration appears to provide adequate prophylaxis.

Administration, Oral↗

Is obesity a risk factor for prostate cancer, and does it even matter? A hypothesis and different perspective.

Measurement of obesity is not as simple as its definition. Currently, several methods of measuring obesity are used in clinical studies. Skinfold thickness, crude weight, lean body mass (LBM), body mass index (BMI), and waist-to-hip ratio (WHR) are some of the more popular methods, but each contains its inherent strengths and flaws. In general, the results of the largest studies on prostate cancer and obesity have not been conclusive. One of the largest studies found an inverse relation to prostate cancer in the youngest age groups. The age and duration of obesity or any rapid changes in weight gain, along with other unhealthy exposures, may have some relation to prostate cancer incidence and mortality. Early intrinsic or extrinsic exposure to estrogen or estrogenlike compounds may provide a protective effect. The timing and duration of a higher estrogen and/or lower testosterone exposure may have a beneficial or detrimental impact on the prognosis of an established prostate tumor. Negative exposures over time such as low levels of sex hormone-binding globulin (SHBG), a greater exposure to growth factors, elevated insulin levels, greater sympathetic activity, higher cholesterol levels, immune system dysfunction, inadequate diets, smoking status, and other factors may be associated with an increased risk of prostate cancer and other diseases. Obesity may also be associated with other cancers for similar and different reasons. For example, morbidity and mortality from postmenopausal breast cancer, colon, kidney, and other cancers are potentially associated with obesity. Other comorbidities such as cataracts, coronary heart disease, diabetes, erectile dysfunction, hypertension, and others are also associated with obesity. The 2 largest prospective studies on BMI and overall mortality have also demonstrated the substantial negative impact of excess weight on society. Prostate cancer risk and obesity need further research to establish if a true association exists, but at this time, does it really matter? Overall, the profound adverse effect of being obese on general health is dramatic, and this is what clinicians and patients need to remember.

Adipose Tissue↗

Transcript mutations of the alpha regulatory subunit of protein kinase A and up-regulation of the RNA-editing gene transcript in lupus T lymphocytes.

BACKGROUND: Systemic lupus erythematosus (SLE) is an autoimmune disorder characterised by diverse dysfunctions of immune effector cells, including proliferation and cytotoxicity. In T cells from patients with SLE, activity of type 1 protein kinase A isozymes is greatly reduced because of decreased expression of the alpha and beta regulatory subunits (RI alpha and RI beta). We aimed to identify a molecular mechanism or mechanisms for this isozyme deficiency by assessing occurrence of mutations in transcripts of the RI alpha subunit in patients with SLE. METHODS: We cloned and sequenced cDNA of RI alpha and corresponding genomic DNA of the coding region to detect sequence changes from eight patients with SLE and six healthy controls. Because transcript editing is regulated by adenosine deaminases that act on RNA (ADAR), we quantified expression of ADAR1 transcripts in SLE and control T cells by competitive PCR. FINDINGS: Sequence analyses of cDNA showed heterogeneous transcript mutations, including deletions, transitions, and transversions. We identified 1.22 x 10(-3)/bp transcript mutations in SLE T cells-a frequency 7.5 times higher than that in control T cells. By contrast, we identified no genomic mutations. Two hotspots were identified in the RI alpha subunit transcripts from SLE T cells, one located adjacent to a pseudosubstrate site of the RI alpha subunit and the other a component of the cAMP binding A domain. ADAR1 mRNA content was 3.5 times higher in SLE cells than in control T cells (p=0.001). INTERPRETATION: An RNA-editing enzyme could be converting adenosine to inosine within double-stranded regions of RNA, resulting in transcript mutations. This process could be one mechanism resulting in mutations in the RI alpha subunit of type 1 protein kinase A.

Adenosine Deaminase↗

Cervical cancer.

Cervical cancer is a serious health problem, with nearly 500000 women developing the disease each year worldwide. Most cases occur in less developed countries where no effective screening systems are available. Risk factors include exposure to human papillomavirus, smoking, and immune-system dysfunction. Most women with early-stage tumours can be cured, although long-term morbidity from treatment is common. Results of randomised clinical trials have shown that for women with locally advanced cancers, chemoradiotherapy should be regarded as the standard of care; however, the applicability of this treatment to women in less developed countries remains largely untested. Many women with localised (stage IB) tumours even now receive various combinations of surgery and radiotherapy, despite unresolved concern about the morbidity of this approach compared with definitive radiotherapy or radical surgery. Treatment of recurrent cervical cancer remains largely ineffective. Quality of life should be taken into account in treatment of women with primary and recurrent cervical cancer.

Adenocarcinoma↗

Association of autonomic nervous hyperreflexia and systemic inflammation in patients with Crohn's disease and ulcerative colitis.

The autonomic nervous system modulates gastrointestinal motility, secretion and mucosal immunity. Its dysfunction may be of pathogenetic importance in inflammatory bowel disease (IBD). This study aimed at investigating the autonomic nervous function in patients with IBD. Forty-seven patients with IBD, 28 with Crohn's disease (CD) and 19 with ulcerative colitis (UC), were investigated by means of 5 cardiovascular and 2 pupillary standardized autonomic nervous function tests. In CD and UC, cardiovascular autonomic neuropathy was very rare (0%, 5%), whereas pupillary autonomic neuropathy was more prevalent (21%, 21%). In contrast to autonomic neuropathy, overall cardiovascular (CD: 29%, UC: 26%) and pupillary autonomic hyperreflexia (46%, 37%) were found more often. Patients with CD and UC demonstrated elevated percentiles in the respiratory sinus arrhythmia test as compared to controls (RSA: 82.3 +/- 3.9%, 80.0 +/- 5.9%, controls: 50.0% +/- 1.5%, p < 0.0001). CD patients with, as compared to patients without, RSA hyperreflexia had significantly higher CDAIs (p < 0.001), increased erythrocyte sedimentation rates (p < 0.005) and more often extraintestinal disease manifestations (p < 0.001). UC patients with, as compared to patients without, pupillary latency time hyperreflexia had lower hemoglobin (p < 0.05), lower albumin (p < 0.01) and increased erythrocyte sedimentation rates (p < 0.05). Autonomic hyperreflexia was significantly associated with more severe inflammation and systemic disease in IBD. Hyperreflexia may be a response to inflammation or a pathogenetic element that drives mucosal inflammation.

Adolescent↗

Low levels of ionic mercury modulate protein tyrosine phosphorylation in lymphocytes.

The ability of ionic mercury to induce protein tyrosine phosphorylation in mouse spleen cells and in the mouse WEHI-231 B-cell lymphoma was investigated. We have confirmed previous studies which showed that exposure to high levels (several hundred microM) of mercury lead to very large increases in the level of protein tyrosine phosphorylation in these cell systems. However we have also demonstrated that low levels (in the order of 0.1 to 1.0 microM) of mercury also significantly upregulate protein tyrosine phosphorylation. Mercury induced protein tyrosine phosphorylation is inhibited by the mercury chelator penicillamine and by pretreating treating target cells with the sulfhydryl blocking reagent N-hydroxymaleimide. These results suggest that exposure to low levels of mercury could potentially interfere with lymphocyte signal transduction and so offer a possible explanation as to how mercury exposure could lead to immune cellular dysfunction. On a molecular level, the results suggest that the site(s) of action with respect to mercury dependent induction of protein tyrosine phosphorylation is likely a free disulfide group or groups located on the outer leaflet of the plasma membrane.

Animals↗

Iron toxicity and antioxidant nutrients.

Iron is an essential nutrient for the growth, development, and long-term survival of most organisms. High tissue iron concentrations have been associated with the development and progression of several pathological conditions, including certain cancers, liver and heart disease, diabetes, hormonal abnormalities, and immune system dysfunctions. In this review we discuss the relevance of iron toxicity on free radical-mediated tissue damage, and how iron interactions with nutrient antioxidants and other metals can affect the extent of oxidative damage to different biomolecules. It can be concluded that the ingestion of antioxidant rich foods may prevent or delay primary and secondary effects associated with iron overload-related diseases.

Animals↗

Effect of the chlorinated hydrocarbons heptachlor, chlordane, and toxaphene on retinoblastoma tumor suppressor in human lymphocytes.

Organochlorine use over the past 50 years has resulted in the contamination of soil, water, plant and animal species. This contamination has created a long-lasting environmental problem, as the members of the organochlorine class of pesticides are resistant to degradation and have been labeled as persistent bioaccumulators. Studies have shown certain organochlorines to be tumor promoters, liver toxicants and to induce immune cell dysfunction in rats and mice. Our laboratory has shown that the organochlorines heptachlor and chlordane affect leukocytic gene expression and differentiation. In this study, experiments with CEM x 174 cells, a hybrid of human T and B cells, were performed to investigate the effects of the tumor promoter heptachlor and its congeners chlordane and toxaphene on retinoblastoma (Rb) gene expression. The results indicated that heptachlor, chlordane or toxaphene, in the range of 10-50 microM, were able to reduce Rb protein levels in a concentration-dependent manner. In the case of heptachlor, the reduction could be seen as early as 12 h and was time-dependent. Analysis of Rb mRNA levels revealed no detectable difference over the same concentration range. These results suggest that members of the organochlorine class are able to downregulate Rb expression at the post-transcriptional level, an effect similar to that on p53 tumor suppressor previously reported by our laboratory.

Blotting, Western↗

Neuronal plasticity and stressor toxicity during aging.

Brain aging, Alzheimer disease and stroke share common elements of deficits in calcium regulation, declines in mitochondrial function, increases in generation of reactive oxygen species (ROS), accumulated damage from ROS and immune system dysfunction. The problem is to distinguish less significant side reactions, such as gray hair, from aspects of aging that contribute to disease. Toward establishing cause and effect relationships, a neuron cell culture system is described that allows comparisons with age under uniform environmental conditions. This neuron culture model indicates that susceptibility to death by apoptosis and consequences of the inflammatory response from beta-amyloid are age-related and an inherent characteristic of the neurons. Further mechanistic investigations are possible. New therapeutic approaches are suggested that combine inhibition of calcium overloads (calcium channel blockers), reduced ROS damage (melatonin, N-acetyl-cysteine), and bolstered mitochondrial function and energy generation (creatine). Together with newly demonstrated capabilities for adult and aged neuron regeneration and multiplication, i.e. plasticity, these approaches offer new hope toward reversing age-related decrements and damage from neurodegenerative disease.

Aging↗

Evaluation of pulmonary infiltrates in critically ill patients with cancer and marrow transplant.

Pulmonary infiltrates in critically ill patients with cancer or marrow transplant can be evaluated by the differential diagnosis presented at the beginning of this article. The patient's quantitative immune system dysfunction, epidemiologic history and chest radiographic findings (pattern, rapidity, and time of onset) will help focus the differential diagnosis. In this patient population, however, common diagnoses can have atypical presentations, unusual diagnoses do occur, and more than one process may be responsible for a patient's infiltrates. Early bronchoscopy to rule out infection is the focus of diagnostic testing. Surgical lung biopsy in this patient population has a low yield.

Algorithms↗

Matrix metalloproteinase-9 and its natural inhibitor TIMP-1 expressed or secreted by peripheral blood mononuclear cells from patients with systemic lupus erythematosus.

Matrix metalloproteinase-9 (MMP-9) was involved in inflammation and immune system dysfunctions. Besides immunologic abnormalities, systemic lupus erythematosus (SLE) also presents chronic inflammatory components. Therefore, a role of MMP-9 in SLE pathology might be supposed. To verify this hypothesis, SLE patients and healthy donors were compared for the MMP-9 and MMP-9 mRNA levels in peripheral blood mononuclear cells (PBMCs), the spontaneous secretion of MMP-9 and TIMP-1 and the MMP-9 activity. Thus, we found that fresh PBMCs from SLE patients expressed a significantly higher activity of MMP-9 and spontaneously released higher levels of MMP-9, as compared to healthy donors, while the secreted TIMP-1 level was the same for both groups. When the patients were sub-grouped based on disease status, the most increased pro-MMP-9 activity inside the PBMCs was identified for relapse SLE sub-group. A similar observation for SLE patients with positive serum fibrinogen was found. Following culture, the PBMCs from remission SLE patients secreted significantly higher MMP-9 level, than the PBMCs from relapse SLE patients. PBMCs from relapse SLE patients secreted the highest levels of TIMP-1, although this difference was not statistically significant. Taken together, these observations suggested the multiple roles of MMP-9 and TIMP-1 in progress of inflammation and tissue damage and/or in repair, depending on clinical stages of SLE.

Autoimmunity↗

Genetic analysis and gene expression of human immunodeficiency virus.

Ten years after the initial description of acquired immune deficiency syndrome, its causative agent, the human immunodeficiency virus, remains the subject of intense scientific interest. Recent research has focused on the detailed analysis of the molecular principles governing gene expression and virion formation and on the cause of immune system dysfunction. Within the past year, considerable progress has been made regarding both the role of the regulatory proteins and the mechanism by which they function, and the determinants of cell tropism and of virion formation.

Gene Expression Regulation, Viral↗