Cistron mapping of tobacco vein mottling virus

The location and order of cistrons in the RNA of the potyvirus tobacco vein mottling virus (TVMV) were investigated. Hybrid-arrested translation, using cloned single-stranded DNA probes complementary to various regions of the viral RNA, was performed and the resulting translation products were analyzed by electrophoresis. The pattern of polypeptides produced with each probe was different from that of control reactions containing RNA alone. Immunoprecipitation of reaction products with antisera to five potyviral proteins revealed that, in some cases, portions of cistrons were masked by the DNA probe resulting in the precipitation of altered polypeptides. In other cases, the entire cistron was affected, resulting in the total loss of immunoreactive material. By correlating the location of each DNA probe with the resulting pattern of translation products, it was possible to construct a map of known cistrons and potential coding regions for additional cistrons in the genomic RNA. DNA probes representing several regions of the viral RNA were expressed in E. coli. Immunoprecipitation of cell proteins revealed the presence of TVMV-related polypeptides; the results were consistent with the cistron order determined by hybrid-arrested translation experiments. Our proposed cistron order and the sizes in kilodaltons of the corresponding polypeptides are: 5'-25 kDa unidentified protein-53 kDa helper component protein-50 kDa unidentified protein-70 kDa cylindrical inclusion protein-52 kDa nuclear inclusion protein-56 kDa nuclear inclusion protein-32 kDa coat protein-3'.     

Maternal uniparental disomy of chromosome 13 in a phenotypically normal child.

A case of maternal uniparental disomy of chromosome 13 is described. The subject is a phenotypically normal male who inherited a t(13;13)(p11.2;p11.2) from his mother who is a carrier of this translocation. The mother was ascertained through a history of recurrent abortion and is phenotypically normal. The translocation in both subjects was studied by cytogenetic and DNA analysis and appears to be a true dicentric isochromosome. These findings show that maternal uniparental disomy of chromosome 13 has had no pathological consequences and suggests that there is no imprinting of genes on maternally derived chromosome 13.     

The effects of somatostatin and metiamide on tachyphylaxis of pentagastrin stimulated gastric acid and pepsin secretion in the conscious cat.

1. Pentagastrin stimulated gastric acid and pepsin secretions show parallel rates of tachyphylaxis in the conscious cat. The responses to histamine show only slight tachyphylaxis. 2. Somatostatin 10 microng.kg(-1).hr(-1) inhibits pentagastrin but not histamine stimulated acid secretion and inhibits pentagastrin stimulated pepsin secretion. 3. The inhibition of pentagastrin stimulated acid and pepsin secretion by Somatostatin delays the tachyphylaxis of these responses, but the rates of tachyphylaxis when they do subsequently occur are identical. 4. Metiamide 10 mg-kg(-1)-hr(-1) equally inhibits histamine and pentagastrin stimulated acid secretion but does not inhibit pentagastrin stimulated pepsin secretion. 5. Inhibiton of acid secretion during metiamide infusion neither prevents nor delays acid nor pepsin tachyphylaxis. 6. It is suggested that tachyphylaxis of acid and pepsin secretion is a gastrin receptor phenomenon and that Somatostatin occupies or modifies the behaviour of these receptors, preventing tachyphylaxis. Metiamide, however, exerts its action only on the histmine H2-receptor and not the gastrin receptor mechanism, and this apparently does not prevent or delay acid tachyphylaxis.     

Acute inflammatory response to endotoxin in mice and humans

Endotoxin injection has been widely used to study the acute inflammatory response. In this study, we directly compared the inflammatory responses to endotoxin in mice and humans. Escherichia coli type O113 endotoxin was prepared under identical conditions, verified to be of equal biological potency, and used for both mice and humans. The dose of endotoxin needed to induce an interleukin-6 (IL-6) concentration in plasma of approximately 1,000 pg/ml 2 h after injection was 2 ng/kg of body weight in humans and 500 ng/kg in mice. Healthy adult volunteers were injected intravenously with endotoxin, and male C57BL/6 mice (n=4 to 12) were injected intraperitoneally with endotoxin. Physiological, hematological, and cytokine responses were determined. Endotoxin induced a rapid physiological response in humans (fever, tachycardia, and slight hypotension) but not in mice. Both mice and humans exhibited lymphopenia with a nadir at 4 h and recovery by 24 h. The levels of tumor necrosis factor (TNF) and IL-6 in plasma peaked at 2 h and returned to baseline levels by 4 to 6 h. IL-1 receptor antagonist RA and TNF soluble receptor I were upregulated in both mice and humans but were upregulated more strongly in humans. Mice produced greater levels of CXC chemokines, and both mice and humans exhibited peak production at 2 h. These studies demonstrate that although differences exist and a higher endotoxin challenge is necessary in mice, there are several similarities in the inflammatory response to endotoxin in mice and humans.     

Phenotypic expansion of Bosch–Boonstra–Schaaf optic atrophy syndrome and further evidence for genotype–phenotype correlations

Bosch–Boonstra–Schaaf Optic Atrophy Syndrome (BBSOAS) is an autosomal dominant neurodevelopmental disorder caused by loss‐of‐function variants in NR2F1 and characterized by visual impairment, developmental delay, and intellectual disability. Here we report 18 new cases, provide additional clinical information for 9 previously reported individuals, and review an additional 27 published cases to present a total of 54 patients. Among these are 22 individuals with point mutations or in‐frame deletions in the DNA‐binding domain (DBD), and 32 individuals with other types of variants including whole‐gene deletions, nonsense and frameshift variants, and point mutations outside the DBD. We corroborate previously described clinical characteristics including developmental delay, intellectual disability, autism spectrum disorder diagnoses/features thereof, cognitive/behavioral anomalies, hypotonia, feeding difficulties, abnormal brain MRI findings, and seizures. We also confirm a vision phenotype that includes optic nerve hypoplasia, optic atrophy, and cortical visual impairment. Additionally, we expand the vision phenotype to include alacrima and manifest latent nystagmus (fusional maldevelopment), and we broaden the behavioral phenotypic spectrum to include a love of music, an unusually good long‐term memory, sleep difficulties, a high pain tolerance, and touch sensitivity. Furthermore, we provide additional evidence for genotype–phenotype correlations, specifically supporting a more severe phenotype associated with DBD variants.     

Assessment of new radioimmunoassay kit for determining urinary albumin at low concentrations: comparison with radial immunodiffusion.

The assay characteristics of a new radioimmunoassay kit for determining urinary albumin at low concentrations were studied. The sensitivity for urinary albumin was 2 mg/l, the analytical range 2 to 40 mg/l, and interassay coefficient of variation less than 12%. In a method comparison study entailing diabetic urine samples covering an albumin concentration of 2 to 150 mg/l the kit compared adequately with radial immunodiffusion (mean difference between methods = 2 mg/l; residual standard deviation = 4.6 mg/l), absolute variation between methods increasing with the concentration. The kit required much less skill than radial immunodiffusion but its capital and running cost were higher.     

Retention and dissociation of tobacco mosaic virus by tobacco protoplasts

When tobacco protoplasts were inoculated with radioactive tobacco mosaic virus (TMV) at a concentration of 1 μg/ml, about 15% of the particles (approximately 8 × 10³ particles per protoplast) were retained. When poly-l-ornithine was not included in the inoculum, the amount of virus retained was reduced 6- to 30-fold. Maximum retention was observed 20–30 min after the addition of virus to the protoplasts.Thirty minutes after mixing virus and protoplasts, about 5% of the protein of the retained TMV had been removed and some of the virus particles appeared to be partially dissociated. A considerable amount of the retained viral material in extracts of inoculated protoplasts was found in the pellets after sucrose gradient centrifugation. This abnormally rapid sedimentation was correlated with the presence of poly-l-ornithine in the inoculum.     

Neurobehavioral Symptoms and Family Functioning in Traumatically Brain-Injured Adults

Traumatic brain injury (TBI) often results in a myriad of symptoms across physical, cognitive, and neurobehavioral domains. Despite inherent limitations associated with physical or cognitive impairments, the extant literature suggests that neurobehavioral symptoms tend to be the most distressing symptoms for the family and are more strongly related to poor outcome for the patient. The Neuropsychology Behavior and Affect Profile (NBAP) along with the General Functioning subscale of the Family Assessment Device (FAD-GF) and the Perceived Stress Scale were administered to 153 family members of persons who had sustained a TBI. The results provide new normative data and statistical support for the NBAP as a promising measure of neurobehavioral symptomatology following TBI. The correlation of.54 (p <.01) between FAD-GF and Full Scale NBAP scores provides powerful support for the hypothesis that family dysfunction is related to the presence of neurobehavioral symptoms in the patient. NBAP domains of Depression, Inappropriateness, Pragnosia, and Indifference appear most strongly related to family functioning and also bear a significant relationship to caregiver stress level and patient unemployment, whereas injury severity had little impact on either family functioning or neurobehavioral symptoms. The findings reinforce the significance of neurobehavioral symptoms and fortify their proposed link to family dysfunction post-TBI.     

Phospholipase A2 contamination of cobra venom factor preparations. Biologic role in complement-dependent in vivo reactions and inactivation with p-bromophenacyl bromide

Cobra venom factor (CoF), the anticomplementary protein in Naja naja cobra venom, is usually purified by sequential ion exchange and gel filtration chromatography. CoF prepared in this manner contains small but significant quantities of phospholipase A2 activity. This acyl hydrolase activity can be simply and efficiently removed on a large scale by treatment of CoF with p-bromophenacyl bromide (BPB), an irreversible modifier of the histidine residue in the active site of phospholipase A2. BPB treatment does not alter the anticomplementary activity of CoF. In vivo experiments utilizing intratracheal injections of control and BPB-treated CoF, as well as pure phospholipase A2, revealed that contaminating phospholipase A2, and not the anticomplementary protein, was responsible for the observed acute neutrophil-associated lung injury. However, phospholipase A2 had no effect on the hypotensive and thrombocytopenic effects of CoF infected intravenously into rabbits. Depletion of circulating C3-C9 by intraperitoneal injections of CoF was not altered by removal of phospholipase A2 activity with BPB.