Hamster endogenous retrovirus (HaER) isolated from SV-40 induced tumor cells

A hamster cell line obtained from a secondary transplanted SV-40-induced tumor was found to spontaneously release type C virus particles. The particles possessed all biochemical features characteristic of retroviruses and induced syncytium formation in XC cells but were not oncogenic for hamsters. Nucleic acid hybridization assays demonstrated that the isolated virus was an endogenous retrovirus of hamster, lacking sequence homology with mouse and other animal species.     

Detection and typing of herpes simplex DNA in genital swabs by real-time polymerase chain reaction

The LightCycler polymerase chain reaction (PCR) is a sensitive assay for the detection of Herpes simplex virus (HSV) DNA in muco-cutaneous swabs. Software-based analysis of the probe melting temperature (Tm) can be used to discriminate between HSV types (HSV-1 and HSV-2). Among 76 HSV DNA positive genital swabs, atypical Tms were observed in 14 (18%). The 14 samples were all typed as HSV-2 by sequence alignment. In 4/14 samples, the atypical Tm was associated with sequence variation at the probe-binding site. Among 10 samples with conserved sequences, Tms were influenced by the specimen preparation method prior to PCR. These findings indicate that multiple factors including, but not limited to sequence variation complicate melting curve analysis following real-time PCR. Alternative typing methods are recommended for specimens with atypical melting curves.     

Histological score for cells with irregular nuclear contours for the diagnosis of reflux esophagitis in children

Histological criteria for the diagnosis of reflux esophagitis include basal zone hyperplasia, stromal papillae elongation, and inflammatory infiltrate. However, endoscopic esophageal biopsy specimens may include little or no lamina propria. Intraepithelial T lymphocytes, seen in hematoxylin and eosin-stained sections as cells with irregular nuclear contours (CINC), may have a higher density in children with esophagitis. We evaluated the diagnostic accuracy of a numerical score built up by grading the "classical" parameters and its correlation with CINC density in grasp biopsy specimens obtained from children undergoing esophagogastroduodenoscopy with and without esophagitis. We analyzed esophageal biopsy specimens from 349 children (median age, 5 years) subdivided in 4 groups according to the previous routine histology report: group 1, 144 children with esophagitis; group 2, 65 controls; group 3, 51 children with dubious esophagitis; and group 4, 75 children with esophagitis on endoscopy but a normal histology report. A numerical value was assigned to each parameter; the sum of these values represented the histological score. We also evaluated intraepithelial CINC density (ie, number of CINC per high-power field). We separately analyzed histological sections with and without lamina propria. For both total score and for CINC density, we calculated a cutoff using a receiver operating characteristic curve. Cutoffs of 6 for score and of 4 for CINC density provided the best sensitivity and specificity. Sensitivity of the histological score was better in biopsy specimens containing lamina propria (94%) than in those without lamina propria (4%). Sensitivity of CINC density was satisfactory in both specimens with (78%) and without (75%) lamina propria. Specificity was satisfactory for both parameters. In conclusion, when lamina propria was present in sections of endoscopic esophageal biopsy specimens, histological score provided a better diagnostic accuracy for the diagnosis of esophagitis. However, when no lamina propria was present, as was the case in 67% of our children, CINC density had better sensitivity. In addition, this latter parameter showed esophageal mucosa damage in 34% of previously dubious cases or cases with esophagitis at endoscopy but a previous routine histology report of normal mucosa.     

Pain in individuals with RASopathies: Prevalence and clinical characterization in a sample of 80 affected patients

Pain in individuals with RASopathies is a neglected topic in literature. In this article, we assessed prevalence and profile of pain in a sample of 80 individuals affected by RASopathies. The study sample included individuals with Noonan syndrome (N = 42), Costello syndrome (N = 17), and cardio‐facio‐cutaneous syndrome (N = 21). A set of standardized questionnaires and scales were administered (VAS/numeric scale, r‐FLACC, Wang‐Baker scale, NPSI, BPI, NCCPC‐R) to detect and characterize acute and chronic pain and to study the influence of pain on quality of life (PEDs‐QL, SF‐36) and sleeping patterns (SDSC); revision of past medical history and multisystemic evaluation was provided. Available clinical data were correlated to the presence of pain. High prevalence of acute (44%) and chronic (61%) pain was documented in the examined sample. Due to age and intellectual disability, acute pain was localized in 18/35 individuals and chronic pain in 33/49. Muscle‐skeletal and abdominal pain was more frequently reported. The intensity of acute and chronic pain interfered with daily activities in 1/3 of the sample. Pain negatively impacted on QoL and sleeping patterns. This work documents that pain is highly prevalent in RASopathies. Future studies including subjective and objective measures of pain are required to discriminate a somatosensory abnormality from an abnormal elaboration of painful stimuli at a central level.     

Fibrillar beta-amyloid peptide Aβ1–40 activates microglial proliferation via stimulating TNF-α release and H2O2 derived from NADPH oxidase: a cell culture study

Background  

Alzheimer's disease is characterized by the accumulation of neuritic plaques, containing activated microglia and β-amyloid peptides (Aβ). Fibrillar Aβ can activate microglia, resulting in production of toxic and inflammatory mediators like hydrogen peroxide, nitric oxide, and cytokines. We have recently found that microglial proliferation is regulated by hydrogen peroxide derived from NADPH oxidase. Thus, in this study, we investigated whether Aβ can stimulate microglial proliferation and cytokine production via activation of NADPH oxidase to produce hydrogen peroxide.     

Investigation of the effect of different regulatory peptides on adrenocortical cell proliferation in immature rats: evidence that endogenous adrenomedullin exerts a stimulating action

Pseudoachondroplasia (PSACH) is an autosomal dominant disorder characterized by disproportionate short stature and precocious osteoarthritis. Radiographic manifestations include epiphyseal, metaphyseal and vertebral abnormalities. Mutations in the cartilage oligomeric matrix protein (COMP) have been identified to cause PSACH. Most of them affect one of the eight calcium-binding domains of COMP. We describe a clinically and radiologically typical PSACH 4-year-old girl and her 31-year-old father. A novel mutation, 1345-1347CCC deletion in exon 13, of COMP was identified in both patients. The deletion would be expected to result in the loss of the conserved proline at codon 449 from the sixth calcium-binding domain. This result further supports that COMP is the only gene, discovered to date, responsible for PSACH across different populations and that the calcium-binding domains are important to the function of the normal COMP.     

Fibrolamellar Carcinoma of Liver: A Primary Malignant Oncocytic Carcinoid?

Immunohistochemical and ultrastructural findings in two cases of fibrolamellar carcinoma of the liver and two cases of hepatocellular carcinoma of the common histologic type are described. Ultrastructural examination of both cases of fibrolamellar carcinoma revealed the presence of neurosecretory (NS) granules which were sparse in some cells and abundant in others. Many of the tumor cells had a distinct oncocytic appearance with abundant mitochondria. A portion of the glutaraldehyde-fixed neoplasm was processed for the uranaffin reaction (an ultrastructural cytochemical stain specific for the NS granules of neuroendocrine tissue). Abundant uranaffin-positive granules were found in the neoplastic cells of both cases of fibrolamellar carcinoma, whereas no uranaffin-positive granules were found in hepatocellular carcinoma of the common histologic type. There was no statistical difference in the mean diameter of the uranaffin-positive granules measured from both cases. Immunohisto-chemistry revealed the presence of neuron-specific enolase (NSE) and serotonin in one of the two cases of fibrolamellar carcinoma and no NSE staining in two cases of hepatocellular carcinoma of the common histologic type. These findings suggest that some liver tumors presenting histologically as fibrolamellar carcinoma may be neuroendocrine in nature.     

Nasal versus bronchial and nasal response to oral aspirin challenge: Clinical and biochemical differences between patients with aspirin-induced asthma/rhinitis

BACKGROUND: Aspirin-induced asthma/rhinitis (AIAR) is characterized by the altered metabolism of leukotrienes and proinflammatory prostaglandins. The basal and postchallenge levels of eicosanoids might reflect the clinical and biochemical characteristics of patients with distinct types of hypersensitive responses to aspirin. OBJECTIVE: We compared clinical and eicosanoid profiles of patients with AIAR showing both bronchial and nasal versus isolated nasal responses to aspirin challenge. METHODS: Twenty-three patients with AIAR underwent the single-blind, oral, placebo-controlled aspirin challenge. The bronchial response (BR) was evidenced by dyspnea and spirometry, whereas the nasal response (NR) was evidenced by nasal symptoms and acoustic rhinometry and/or rhinomanometry. Urinary leukotriene E4 (uLTE4), serum and urinary stable prostaglandin D2 metabolite, and 9alpha,11beta-prostaglandin F2 (9alpha,11beta-PGF2), were determined at baseline and after the aspirin challenge. RESULTS: Fifteen subjects showed BR and NR (BNR), whereas 8 showed NR only. Basal uLTE4 in the BNR group was significantly higher than in the NR group. After aspirin challenge, it increased significantly in both groups. Serum 9alpha,11beta-PGF2 increased after aspirin challenge in the BNR group only. The patients with BNR had more severe AIAR. CONCLUSIONS: BNR to aspirin in AIAR indicates a more advanced disease and more profound underlying eicosanoid metabolism disturbances.     

False positive results of mitochondrial DNA depletion/deletion due to single nucleotide substitutions causing appearance of additional PvuII restriction sites.

Human mitochondrial diseases are usually caused by dysfunction of mitochondrial DNA (mtDNA), particularly by point mutations, deletions, or depletions. In commonly used procedures for molecular diagnostics of mitochondrial dysfunction, one of the first steps is linearization of circular mitochondrial genomes with either BamHI or PvuII restriction endonulease, which cuts human mtDNA at a unique site. Here, we describe a case of false positive results, which suggested mtDNA depletion or a large deletion in a patient's tissue sample. More detailed analysis (mtDNA sequencing) revealed that these false positive results were caused by the presence of the 12753A>G substitution in the gene coding for NADH dehydrogenase subunit 5 (ND5). This substitution results in no change in amino acid sequence of the gene product but creates an additional PvuII site. Investigating a population of 200 patients not affected by mitochondrial diseases, we found an additional case of 12753A>G, and also another substitution, 12804T>C, which also results in no change in amino acid sequence of ND5 but creates an additional PvuII site. A few cases of 12753A>G and 12804T>C substitutions were found previously in Asian, American, African, and European populations (though they were not reported to date in the MITOMAP), but those samples were used in population studies and not tested for mtDNA deletion or depletion. Therefore, we present a cautionary report indicating that these mtDNA polymorphisms exist in various human populations (and thus, they are panethnic) and may cause false positive results of standard molecular analyses, including molecular diagnostics, of human mtDNA.