Chromosome 21-Encoded microRNAs (mRNAs): Impact on Down's Syndrome and Trisomy-21 Linked Disease.

Down's syndrome (DS; also known as trisomy 21; T21) is caused by a triplication of all or part of human chromosome 21 (chr21). DS is the most common genetic cause of intellectual disability attributable to a naturally-occurring imbalance in gene dosage. DS incurs huge medical, healthcare, and socioeconomic costs, and there are as yet no effective treatments for this incapacitating human neurogenetic disorder. There is a remarkably wide variability in the 'phenotypic spectrum' associated with DS; the progression of symptoms and the age of DS onset fluctuate, and there is further variability in the biophysical nature of the chr21 duplication. Besides the cognitive disruptions and dementia in DS patients other serious health problems such as atherosclerosis, altered lipogenesis, Alzheimer's disease, amyotrophic lateral sclerosis (Lou Gehrig's disease), autoimmune disease, various cancers including lymphoma, leukemia, glioma and glioblastoma, status epilepticus, congenital heart disease, hypotonia, manic depression, prostate cancer, Usher syndrome, motor disorders, Hirschsprung disease, and various physical anomalies such as early aging occur at elevated frequencies, and all are part of the DS 'phenotypic spectrum.' This communication will review the genetic link between these fore-mentioned diseases and a small group of just five stress-associated microRNAs (miRNAs)-that include let-7c, miRNA-99a, miRNA-125b, miRNA-155, and miRNA-802-encoded and clustered on the long arm of human chr21 and spanning the chr21q21.1-chr21q21.3 region.

Clinical Characteristics of Idiopathic Granulomatous Mastitis in a Hispanic Border Population: A Case Series and Literature Review.

Idiopathic granulomatous mastitis (IGM) is an autoimmune condition of the breast that is commonly encountered in women of non-white ethnicity such as Southeast Asians, Middle Easterners, and Hispanics. This condition often presents as a painful breast mass, and many patients undergo invasive diagnostic procedures or surgical excision, which can lead to disfiguring scars. Early recognition and prompt treatment with immunosuppressive medications can prevent invasive workups and management. Although previously thought to require an exclusively surgical approach, it now prompts interdisciplinary management. In this context, we present a case series of patients with IGM in a Hispanic population of South Texas.

Rhizospheric, seed, and root endophytic-associated bacteria of drought-tolerant legumes grown in arid soils of Namibia.

Plant growth-promoting bacteria (PGPB) are of increased interest as they offer sustainable alternatives to the more common chemical fertilisers. Research, however, has increased into the use of PGPB as bioinoculants to improve yields. Legumes are known to interact with diazotroph PGPB which increase nutrient uptake, prevent pathogenic infections, and actively fix nitrogen. This study aimed to comprehensively describe PGPB associated with legumes grown in Namibia through analysis of the site-specific bacterial microbiomes. In the present study, we used the 16S rRNA sequencing approach to determine the structure of rhizosphere, root, and seed endosphere microbiomes of five drought-tolerant legume species: Macrotyloma uniflorum, Vigna radiata, Vigna aconitifolia, Vigna unguiculata and Lablab purpureus. Several important phyla were identified including Actinobacteriota, Bacteroidota, Firmicutes, Proteobacteria and Verrucomicrobiota. Overall, Proteobacteria was the most abundant phylum followed by Actinobacteria. The most important genera identified were Bacillus, Mesorhizobium, Pseudomonas, Bradyrhizobium and the Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium group. The relative abundance of these genera varied across sample types and legume species. This study identified important diazotrophs across all the legume species. Bacillus, an important PGPB, was found to be the most abundant genus among all the niches analysed and legume species, while Rhizobium spp. was particularly enriched in roots. This study ultimately provides previously undescribed information on legume-associated bacterial communities in Namibia.

Bitten to the Bone: A Case of Anxiety-Induced Osteomyelitis.

Onychophagia is a habitual nail-biting disorder, usually associated with mental or emotional diseases. It affects 20-30% of the population in all age groups. Human bites have the potential to become serious injuries due to high virulence in the human oral flora and may often require hospital admission, antibiotics and even debridement in the operating room. Thus, repetitive nail biting has the potential to be limb-threatening if not treated early and appropriately. We present a 49-year-old Spanish-speaking gentleman, with a past medical history of repetitive nail biting secondary to severe anxiety, major depression disorder, bilateral hand neuropathy secondary to diabetes mellitus (DM) type 2 who was initially admitted to the hospital due to cellulitis of the fingers with suspected osteomyelitis in the right hand. Anxiety was being treated by psychiatrist with paroxetine however, given no improvement and prolonged follow-ups, the primary care physician (PCP) added hydroxyzine and scheduled alprazolam in an attempt to minimize symptoms. Despite these efforts, patient continued with nail biting. On initial physical exam, the patient had a lack of fingernails and multiple wounds at various stages of healing across all digits. The distal and middle phalanges of the third right digit showed increased erythema and swelling and band tightening. Patient was started on broad-spectrum antibiotics. Initial radiography of the right hand was concerning for osteomyelitis which was later confirmed with Magnetic Resonance Imaging (MRI). Infectious disease specialist agreed on a course of cefepime, vancomycin and metronidazole. On admission, hand surgeon did not see a need for amputation and patient was treated conservatively. Due to minimal improvement after six days on IV antibiotics, patient underwent fasciotomy of the flexor compartment of the right middle finger after patient rejected hand surgeon's recommendation for amputation. He was discharged to a skilled nursing facility where he was to continue intravenous antibiotics for an additional four weeks. The vulnerable patient population of South Texas is predominately Hispanic, Spanish-speaking and uninsured. It is imperative to treat psychiatric disorders early to prevent complications, however, given the low numbers of psychiatrists in the Rio Grande Valley and even fewer who speak Spanish it is not unusual to find an appointment in more than six months. In this case, we observe how a trivial everyday behavior can lead to limb-threatening complications if not treated early and appropriately.

Acute Hypersensitivity Reaction After Casirivimab/Imdevimab Infusion in a COVID-19-Positive Young Male: Myopericarditis or Kounis Syndrome?

Myocarditis has been a rare, but well-documented side effect of the mRNA-based vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as well as a complication of viral infections including SARS-CoV-2. However, myopericarditis as a complication of monoclonal antibody infusion or as a complication of allergic reaction to antibody infusions might be underreported. We report the case of a 30-year-old man with a previous diagnosis of coronavirus disease 2019 (COVID-19) infection one week prior to presentation, unvaccinated for SARS-CoV-2, who was referred from a monoclonal infusion center where he received casirivimab/imdevimab and 15 minutes after the infusion began to complain of chills, chest pain, shortness of breath, and was hypotensive. In the infusion center, the patient received epinephrine and diphenhydramine and was directed to the ER, where the patient was febrile, tachycardic, and hypotensive. Initial troponin was 1.91 which peaked at 11.73 and CK-MB which peaked at 21.2. EKG had no ischemic changes. A two-dimensional echocardiogram showed an ejection fraction (EF) of about 45%, with a left ventricular dysfunction and trivial posterior pericardial effusion, and it was diagnosed as myopericarditis. On admission, he was started on full-dose enoxaparin, aspirin, fluid resuscitation, steroids, remdesevir, and bilevel positive airway pressure (BiPap) due to his respiratory compromise. Three days later, with clinical improvement, a repeat echocardiogram showed EF of 65%, with normal ventricular contractility and no pericardial effusion. The patient was discharged home with close cardiology follow-up. Though this could be a simple case of viral myopericarditis with troponinemia secondary to demand-ischemia, the differential should be broadened to complication of monoclonal antibody, given the sudden symptom onset after infusion completion and/or a possible Kounis syndrome. Though there have not been any reported cases of casirivimab/imdevimab causing myopericarditis, adverse cardiac events after monoclonal therapy have been reported mainly in cancer patients receiving monoclonal infusions.

Early insight into the potential contribution of aluminum to neurodegeneration - A tribute to the research work of Robert D. Terry, Igor Klatzo, Henryk M. Wisniewski and Donald R.C. Mclachlan.

The first successful attempt to obtain purified aluminum metal was accomplished by the Danish physicist and chemist Hans Christian Orsted in 1824, however it was not until about ~140 years later that aluminum's capacity for neurological disruption and neurotoxicity was convincingly established. The earliest evidence of the possible involvement of this biosphere-rich metallotoxin in Alzheimer's disease (AD) originated in the early-to-mid-1960's from animal and human research investigations that arose almost simultaneously from independent laboratories in the United States and Canada. This short communication pays tribute to the pioneering research work on aluminum in susceptible species, in AD animal models and in AD patients by the early investigators Drs. Robert D. Terry, Igor Klatzo and Henryk M. Wisniewski with special acknowledgement to the late Dr. Donald RC McLachlan, and their contemporary physician-scientist colleagues and collaborators. Together these researchers established the groundwork and foundation towards our understanding of the potential contribution of aluminum to progressive, age-related and lethal neurodegenerative diseases of the human central nervous system.

Aluminum-induced generation of lipopolysaccharide (LPS) from the human gastrointestinal (GI)-tract microbiome-resident Bacteroides fragilis.

Gram-negative bacteria of the human gastrointestinal (GI) tract microbiome: (i) are capable of generating a broad-spectrum of highly neurotoxic, pro-inflammatory and potentially pathogenic molecules; and (ii) these include a highly immunogenic class of amphipathic surface glycolipids known as lipopolysaccharide (LPS). Bacteroides fragilis (B. fragilis), a commensal, Gram negative, non-motile, non-spore forming obligatory anaerobic bacillus, and one of the most abundant bacteria found in the human GI tract, produces a particularly pro-inflammatory and neurotoxic LPS (BF-LPS). BF-LPS: (i) is known to be secreted from the B. fragilis outer membrane into the external-medium; (ii) can damage biophysiological barriers via cleavage of zonula adherens cell-cell adhesion proteins, thereby disrupting both the GI-tract barrier and the blood-brain barrier (BBB); (iii) is able to transit GI-tract barriers into the systemic circulation and cross the BBB into the human CNS; and (iv) accumulates within CNS neurons in neurodegenerative disorders such as Alzheimer's disease (AD). This short communication provides evidence that the incubation of B. fragilis with aluminum sulfate [Al2(SO4)3] is a potent inducer of BF-LPS. The results suggest for the first time that the pro-inflammatory properties of aluminum may not only be propagated by aluminum itself, but by a stimulation in the production of microbiome-derived BF-LPS and other pro-inflammatory pathogenic microbial products normally secreted from human GI-tract-resident microorganisms.

Deletions in immunoglobulin polypeptide chains as evidence for breakage and repair in DNA.

The partial sequence of the light chain of the myeloma-like immunoglobulin Sac shows a large deletion in its variable region. The sequence provides evidence that the corresponding gene was formed by the repair of DNA broken at nonhomologous positions. Data from other immunoglobulin (heavy) chains containing large deletions are compatible with their genes also being the result of DNA breakage and nonhomologous repair. Single homologous reciprocal exchanges in DNA networks at immunoglobulin loci could be the cause of the nonhomologous breaks. The relevance of these events to the generation of normal antibody variability remains to be determined.

Analysis of the functional effects of a mutation in SOD1 associated with familial amyotrophic lateral sclerosis.

Mutations in the Cu, Zn superoxide dismutase (SOD1) gene have been reported in some pedigrees with Familial Amyotrophic Lateral Sclerosis (FALS). We have investigated the functional and structural effects of a Gly-->Ser mutation at codon 41 of SOD1 in a pedigree with FALS and the topography of SOD1 expression in the mammalian CNS. These analyses show that the 41Gly-->Ser mutation causes a 27% reduction in Cu, Zn SOD activity. SOD1 is transcribed at high levels in rat motoneurons and four other types of neurons homologous to upper motoneurons that degenerate in human ALS. However, SOD1 is transcribed at lower levels in other types of neurons, such as cerebellar Purkinje cells, which are not usually involved significantly in human ALS. On the other hand, immunocytochemical studies indicate that most types of rat neurons contain similar levels of Cu, Zn SOD immunoreactive protein. Nevertheless, these results suggest that the essential feature causing this subtype of ALS is either a reduction in Cu, Zn SOD activity in cell types that presumably critically require Cu, Zn SOD for protection against oxidative damage or the fact that the mutation in SOD1 associated with FALS results in a novel gain of function that is particularly deleterious to those cell types expressing SOD1 at high levels.

Mutation of the von Hippel-Lindau gene alters human cardiopulmonary physiology.

Intracellular responses to hypoxia are coordinated by the von Hippel-Lindau--hypoxia-inducible factor (VHL-HIF) transcriptional system. This study investigated the potential role of the VHL-HIF pathway in human systems-level physiology. Patients diagnosed with Chuvash polycythaemia, a rare disorder in which VHL signalling is specifically impaired, were studied during acute hypoxia and hypercapnia. Subjects breathed through a mouthpiece and ventilation was measured while pulmonary vascular tone was assessed echocardiographically. The patients were found to have elevated basal ventilation and pulmonary vascular tone, and ventilatory, pulmonary vasoconstrictive and heart rate responses to acute hypoxia were greatly increased, as were heart rate responses to hypercapnia. The patients also had abnormal pulmonary function on spirometry. This study's findings demonstrate that the VHL-HIF signalling pathway, which is so central to intracellular oxygen sensing, also regulates the organ systems upon which cellular oxygen delivery ultimately depends.

Prevalence, Age Profile, and Associated Risk Factors for Hymenolepis nana Infection in a Large Population-Based Study in Northern Peru.

Hymenolepis nana, the dwarf tapeworm, is a common intestinal infection of children worldwide. We evaluated infection and risk factor data that were previously collected from 14,761 children aged 2-15 years during a large-scale program in northern Peru. We found that 1,124 of 14,761 children (7.61%) had H. nana infection, a likely underestimate given that only a single stool sample was examined by microscopy for diagnosis. The strongest association with infection was lack of adequate water (adjusted prevalence ratio [aPR] 2.22, 95% confidence interval [CI] 1.82-2.48) and sanitation infrastructure in the house (aPR 1.94, 95% CI 1.64-2.29). One quarter of those tested did not have a bathroom or latrine at home, which doubled their likelihood of infection. Similarly, one quarter did not have piped public water to the house, which also increased the likelihood of infection. Continued efforts to improve access to basic water and sanitation services will likely reduce the burden of infection in children for this and other intestinal infections.

Human thymus-leukemia-associated antigen: isolation and partial characterization.

Human thymus-leukemia-associated antigen (HThy-L), a saline-soluble antigen, was previously detected by immunodiffusion (but not on the cell surface) in significant quantity in extracts of normal thymocytes, cells from cultured T-cell lines, and erythrocyte-rosette-positive leukemia blasts. Two species of HThy-L were identified and isolated from normal human thymus tissue after extraction in tris buffer, ammonium sulfate fractionation, acid precipitation of inactive fractions, DEAE-cellulose (DE-52) chromatography, Sephadex G-100 gel filtration, and carboxymethyl-cellulose (CM-52) chromatography; On Sephadex G-100, both HThy-L species had a similar molecular weight (40,000--50,000), but they eluted in different positions on DE-52 and CM-52. Analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis showed that each of the 2 HThy-L species contained 2 components with molecular weights of approximately 43,000 and 23,000. Further purification of HThy-L on Sephadex G-50 showed that the 43,000-dalton component possessed HThy-L activity.

The prevalence of CALR mutations in a cohort of patients with myeloproliferative neoplasms.

INTRODUCTION: To investigate the prevalence of calreticulin (CALR) mutations in JAK2- and MPL-non-mutated patients with suspected myeloproliferative neoplasm (MPN) from a large MPN clinic and confirm a diagnosis of MPN. METHODS: JAK2/MPL-non-mutated patients from the Belfast City Hospital (BCH) with either of the MPNs - ET or MF - and diagnosed between 1988 and 2014 were selected for CALR screen. All cases were validated according to the WHO 2008 classification for MPNs. Statistical analysis was performed with Minitab 16 Statistical Software package. Exon 9 of CALR was amplified by PCR using genomic DNA, and mutations were detected by fragment analysis. RESULTS: Of the 62 JAK2/MPL-non-mutated MPN patients screened, 57 had ET and 5 had MF; 34 patients (53.1%) carried CALR mutations. Three of 5 MF patients were CALR positive. Thirty-one ET patients (54.3%) harboured CALR mutation, whereas 26 (45.7%) were classified as 'triple negatives'. CONCLUSION: Detection of CALR mutations in a cohort of JAK2/MPL-non-mutated patients with suspected MPN confirmed the diagnosis of MPN in around 53% of cases. This is lower than initially reported, but similar to subsequent studies. However, a sizable cohort of patients remains lacking a specific molecular marker.

Retroviral-mediated gene transfer of the human erythropoietin gene into a factor-dependent cell line, TF-1.

The factor-dependent cell line, TF-1, established from a patient with erythroleukaemia, shows characteristics of immature erythroblasts. Addition of granulocyte-macrophage colony stimulating factor (GM-CSF) to the culture medium is required for long-term growth of the cells. Erythropoietin (Epo) can also be used to sustain TF-1 cells but for only limited periods (approximately a week). Low levels of both growth factors can act synergistically to maintain proliferation for a longer period of time than Epo alone. To eliminate the requirement of exogenous Epo for growth, TF-1 cells were co-cultured with a retroviral secreting cell line containing the human erythropoietin (hEpo) gene and a neomycin (neo) selectable marker. TF-1 cells which exhibited neo resistance (indicating infection by the retrovirus) were then grown in low concentrations of GM-CSF without the addition of Epo. Under these conditions growth of normal TF-1 cells was not sustained. The neo-resistant cells survived for more than 14 days indicating synergy between GM-CSF and the Epo synthesised by the co-cultured TF-1 cells. Radioimmunoassays performed on growth media detected concentrations up to 1 mU/ml of Epo, implying that stable integration of the retroviral vector and expression of the hEpo gene have been achieved.

The sweet thing about Type 1 diabetes: a cryoprotective evolutionary adaptation.

The reasons for the uneven worldwide distribution of Type 1 diabetes mellitus have yet to be fully explained. Epidemiological studies have shown a higher prevalence of Type 1 diabetes in northern Europe, particularly in Scandinavian countries, and Sardinia. Recent animal research has uncovered the importance of the generation of elevated levels of glucose, glycerol and other sugar derivatives as a physiological means for cold adaptation. High concentrations of these substances depress the freezing point of body fluids and prevent the formation of ice crystals in cells through supercooling, thus acting as a cryoprotectant or antifreeze for vital organs as well as in their muscle tissue. In this paper, we hypothesize that factors predisposing to elevated levels of glucose, glycerol and other sugar derivatives may have been selected for, in part, as adaptive measures in exceedingly cold climates. This cryoprotective adaptation would have protected ancestral northern Europeans from the effects of suddenly increasingly colder climates, such as those believed to have arisen around 14,000 years ago and culminating in the Younger Dryas. When life expectancy was short, factors predisposing to Type 1 diabetes provided a survival advantage. However, deleterious consequences of this condition have become significant only in more modern times, as life expectancy has increased, thus outweighing their protective value. Examples of evolutionary adaptations conferring selection advantages against human pathogens that result in deleterious effects have been previously reported as epidemic pathogenic selection (EPS). Such proposed examples include the cystic fibrosis mutations in the CFTR gene bestowing resistance to Salmonella typhi and hemochromatosis mutations conferring protection against iron-seeking intracellular pathogens. This paper is one of the first accounts of a metabolic disorder providing a selection advantage not against a pathogenic stressor alone, but rather against a climatic change. We thus believe that the concept of EPS should now include environmental factors that may be nonorganismal in nature. In so doing we propose that factors resulting in Type 1 diabetes be considered a result of environmental pathogenic selection (EnPS).

Neurofilament light and polyadenylated mRNA levels are decreased in amyotrophic lateral sclerosis motor neurons.

The presence of large neurofilamentous accumulations in the perikaryon and proximal axon of motor neurons in amyotrophic lateral sclerosis (ALS) suggests that the expression of this abundant cytoskeletal protein may be altered. We performed quantitative in situ hybridization for the low molecular weight neurofilament subunit (NF-L) messenger RNA in six cases of sporadic ALS and six controls. We found a 41% decrease (p < 0.02) in the NF-L mRNA levels in anterior horn cells in ALS, with a 60% decrease (p < or = 0.01) in alpha motor neurons. This alteration may represent a non-specific response to axonal or neuronal injury or, alternatively, reflect the regenerative activity of residual normal motor neurons. NF-L mRNA levels were consistently low (in the third and fourth quartiles) in spheroid-bearing motor neurons, indicating that the neurofilamentous accumulations observed in ALS are not likely the result of overexpression of the NF-L gene. Total neuronal polyadenylated mRNA levels were also 50% lower (p = 0.02) in anterior horn cells and 48% lower (p < or = 0.05) in alpha motor neurons in ALS, possibly reflecting a decrease in selected mRNA species in diseased motor neurons.

Molecular and prospective phenotypic characterization of a pedigree with familial Alzheimer's disease and a missense mutation in codon 717 of the beta-amyloid precursor protein gene.

We present prospective clinical and neuropathologic details of a pedigree segregating familial Alzheimer's disease (FAD) associated with a mutation (G----A substitution) at nucleotide 2149 in exon 17 of the amyloid precursor protein (APP) gene. This mutation, which is predicted to cause the missense substitution of isoleucine for valine at codon 717 of APP, cosegregated perfectly with the FAD trait (lod score = 3.49 at theta = 0.00). The earliest clinical manifestations of the disease relate to deficits in memory function, cognitive processing speed, and attention to complex cognitive sets. These changes occurred in the absence of changes in nonmemory language and visuospatial functions. The neuropathologic features of FAD associated with the APP717 mutation in this family include severe neuronal loss, abundant neurofibrillary tangles, amyloid plaques, and amyloid angiopathy. These results provide independent confirmation that mutations in the APP gene are linked to the FAD trait in some families.

Mutation and expression analysis of human BUB1 and BUB1B in aneuploid breast cancer cell lines.

Genetic instability is a hallmark feature of breast, colorectal and other types of cancers. One type characterized by chromosomal instability is thought to be important in the pathogenesis of many solid tumors displaying aneuploidy. Two related protein kinases and homologues of the yeast checkpoint genes, hBUB1 and hBUB1B, have been implicated in the pathogenesis of colorectal cancers. Mutations in hBUB1 have demonstrated a dominant negative effect by disrupting the mitotic checkpoint when transfected into euploid colon cancer cell lines. In Brca2 deficient murine cells, Bub1 mutants potentiate growth and cellular transformation. This would suggest that aneuploidy in solid tumors including breast, could be the result of defects in mitotic checkpoint genes and may be responsible for a chromosomal instability phenotype contributing to tumor progression. We conducted mutational analysis of 19 aneuploid breast cancer cell lines. No mutations were found but we identified nine sequence variations including five previously unreported sequence variants in hBUB1B, two of which affect restrictions sites. None of these nucleotide changes predict significant changes in the predicted protein structure. Expression analysis by Northern blot of breast cell lines showed variable expression of hBUB1 and hBUB1B genes. This suggest that while regulation of expression of these genes may be important in cancer, the lack of putative deleterious mutations in the coding sequence does not support a frequent role for mutant hBUB1 and hBUB1B alleles in the pathogenesis of breast cancer.