Transferrinfection: a highly efficient way to express gene constructs in eukaryotic cells.
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Adenoviridae↗
Biomedical subjects
S Phillips
Publications and source records attributed to S Phillips.
High-efficiency receptor-mediated delivery of small and large (48 kilobase gene constructs using the endosome-disruption activity of defective or chemically inactivated adenovirus particles.
One limit to successful receptor-mediated gene delivery is the exit of the endocytosed material from the endosome. We demonstrate here the delivery of marker genes to tissue culture cells using a modification of the receptor-mediated gene delivery technique that exploits the endosomolytic activity of defective adenovirus particles. In particular, greater than 90% of the transfected-cell population is found to express a beta-galactosidase gene, and, most importantly, this high level of expression can be obtained with psoralen-inactivated virus particles. Furthermore, because the delivered gene is not carried within the genome of the adenovirus particle, the size constraints are relieved, and we can, therefore, show the delivery of a 48-kilobase cosmid DNA molecule.
Adenoviruses, Human↗
Amphibian oocytes and sphere organelles: are the U snRNA genes amplified?
The sphere organelles (spheres) of Xenopus and other amphibian oocytes are known to contain small nuclear ribonucleoprotein particles (snRNPs) and have been suggested to play a role in snRNP complex assembly. Coupled with the similarities that exist between spheres and nucleoli and the quantitative and kinetic aspects of snRNA synthesis in the Xenopus oocyte, we have investigated whether or not the U snRNA encoding genes are amplified in Xenopus oogenesis, the spheres being possible sites for the location of such extrachromosomal gene copies. By applying a number of quantitative nucleic acid hybridization procedures to both total and fractionated oocyte and somatic DNA, employing both homologous and heterologous U snRNA gene probes and suitable amplification and non-amplification control probes, we show that the U snRNA genes do not undergo any major amplification in Xenopus oogenesis. Therefore, the analogy between the sphere organelles and nucleoli appears to be limited. The role of the spheres and their relationship to other snRNP containing structures, specifically B snurposomes, and the sphere organizer loci remains obscure.
Animals↗
Illness perception and symptom components in chronic fatigue syndrome.
Two-hundred and eight patients with chronic fatigue syndrome (post-viral fatigue syndrome) completed a questionnaire which dealt both with their illness in general and with the extent to which they experienced specific symptoms. A factor analysis of the symptom data yielded four components: emotional distress; fatigue; somatic symptoms; and cognitive difficulty. Emotional disturbance is a common feature of the disorder and its role has been widely debated. When the symptom components were considered independently, fatigue, somatic symptoms and cognitive difficulty were associated with questionnaire items relating to general illness severity, but emotional distress was not. Thus negative emotions did not contribute directly to patients' perception of illness severity. They were, however, correlated with the other symptom components. It is argued that this correlation reflects a reciprocal influence, with negative emotions exacerbating fatigue and other key symptoms and the debilitating nature of these symptoms enhancing emotional vulnerability.
Activities of Daily Living↗
Evaluation of the nutritive value of yellow rice in rats and broiler chicks.
Yellow discoloration often develops in rice kernels during post-harvest storage, due possibly to fungal activity. The present study examined the changes in nutrient composition taking place during yellowing of rice, and the effects of feeding rats and broiler chicks on a moderately yellow rice at 600 g/kg diet. Nitrogen content was found to be higher in rice grains that had become more yellow, only part of the increase being in non-protein-N; however, relative to crude protein (N x 6.25) the concentrations of lysine, methionine, cystine and arginine were lower. There were no significant differences between white and yellow rice in the food intake, weight gain and efficiency of food utilization (EFU) of rats and chicks when diets were formulated to contain similar nutrient concentrations, or the same basal ingredient composition. Diet pelleting increased food intake and weight gain in both animal species, but reduced dry matter and energy digestibility in rats; effects on nutrient retention in chicks were largely non-significant. Liver weights of rats and chicks and pancreas weights of chicks were unaffected by yellow rice; however, chicks fed on mash had a larger pancreas on average than those fed on pellets. Thus, whilst the nutrient composition of rice is altered during yellowing, a moderately yellow rice is unlikely to produce major adverse effects when fed to rats and broiler chicks.
Animal Nutritional Physiological Phenomena↗
Acute megakaryoblastic leukemia in infants with t(1;22)(p13;q13) abnormality.
Six infants with acute megakaryoblastic leukemia and a translocation (1;22)(p13;q13) were studied. There were five female infants and one male infant, and the age at initial examination varied from 0.8 to 6.5 months (median, 2.3 months). All the patients had hepatosplenomegaly and anemia (6 to 8.3 g/dL), and four patients had thrombocytopenia (9,000 to 63,000/mm3). The bone marrow showed prominent fibrosis in five cases and reticulin fibrosis in one patient at presentation. Crush artifact often made the histologic sections difficult to interpret, but typical megakaryoblasts could be identified in the smears. Biopsy specimens of the liver and lymph node were suggestive of a nonhematopoietic malignant condition because of the cohesiveness of the tumor cells, stromal fibrosis, and the prominent sinusoidal and vascular pattern of infiltration. Immunophenotyping of peripheral blood mononuclear cells was helpful in identifying the blasts as belonging to the megakaryoblastic lineage. Using a panel of mononclonal antibodies, it was also possible to confirm the nature of the infiltration in paraffin sections and to differentiate it from other childhood small round cell tumors, especially neuroblastoma in paraffin sections (typical staining pattern: CD45-, CD43+, vW Factor, Ulex europeus I+, CD20-, CD45RO-, synaptophysin-, chromogranin-, cytokeratin-, desmin-). This special type of infantile acute leukemia can be recognized with confidence if one is aware of its clinical features, peculiar pathologic characteristics, the morphologic features and immunophenotype of the megakaryoblasts, and the unique cytogenetic abnormality.
Biopsy↗
Evaluation of protein requirements for trained strength athletes.
Leucine kinetic and nitrogen balance (NBAL) methods were used to determine the dietary protein requirements of strength athletes (SA) compared with sedentary subjects (S). Individual subjects were randomly assigned to one of three protein intakes: low protein (LP) = 0.86 g protein.kg-1.day-1, moderate protein (MP) = 1.40 g protein.kg-1.day-1, or high protein (HP) = 2.40 g protein.kg-1.day-1 for 13 days for each dietary treatment. NBAL was measured and whole body protein synthesis (WBPS) and leucine oxidation were determined from L-[1-13C]leucine turnover. NBAL data were used to determine that the protein intake for zero NBAL for S was 0.69 g.kg-1.day-1 and for SA was 1.41 g.kg-1.day-1. A suggested recommended intake for S was 0.89 g.kg-1.day-1 and for SA was 1.76 g.kg-1.day-1. For SA, the LP diet did not provide adequate protein and resulted in an accommodated state (decreased WBPS vs. MP and HP), and the MP diet resulted in a state of adaptation [increase in WBPS (vs. LP) and no change in leucine oxidation (vs. LP)]. The HP diet did not result in increased WBPS compared with the MP diet, but leucine oxidation did increase significantly, indicating a nutrient overload. For S the LP diet provided adequate protein, and increasing protein intake did not increase WBPS. On the HP diet leucine oxidation increased for S. These results indicated that the MP and HP diets were nutrient overloads for S. There were no effects of varying protein intake on indexes of lean body mass (creatinine excretion, body density) for either group. In summary, protein requirements for athletes performing strength training are greater than for sedentary individuals and are above current Canadian and US recommended daily protein intake requirements for young healthy males.
Adult↗
Rabbit trachealis tension responses to receptor-mediated agonists are diminished by elastase.
The present study examined the effects of elastase, in concentrations present in respiratory secretions, on airway smooth muscle contractile responses in vitro and the magnitude of the airway epithelial inhibition of smooth muscle tension. Experiments were performed on 126 full-thickness tracheal strips from 25 rabbits. Isometric tension responses to acetylcholine (10(-8) to 10(-4) M) and potassium chloride (10 to 110 mM) were examined before and after a 5-min exposure to either porcine pancreatic elastase (PPE) or human neutrophil elastase (HNE). PPE (5 to 40 micrograms/100 microliters) reduced the tension response to acetylcholine but had no effect on the tension response to potassium chloride. PPE and HNE (20 micrograms/100 microliters) produced similar effects. Mechanical removal of the epithelium per se significantly (P less than 0.005) decreased the ED50 response to acetylcholine but did not affect maximal tension. However, the airway epithelial inhibitory effect on the acetylcholine tension response was similar in the presence and absence of PPE (20 micrograms/100 microliters). These data suggest that the diminution of tracheal smooth muscle tension responses to receptor-mediated agonists induced by elastase is a direct effect on the muscle and is not mediated by an effect of elastase on the respiratory epithelium.
Acetylcholine↗
Developmental regulation of the sarcoplasmic reticulum calcium pump in the rabbit heart.
Previous studies have demonstrated that myocardial function changes during mammalian perinatal development. The purpose of this study was to evaluate the subcellular basis underlying the slower relaxation in the developing heart by examining perinatal changes in sarcoplasmic reticulum (SR) function, and in SR Ca2+ pump protein and mRNA abundance. We measured Ca2+ uptake and ATPase rates in isolated fetal, newborn, and adult rabbit cardiac SR membranes. In fetal and adult SR membranes, we estimated the active Ca2+ pump protein content by measuring the steady state Ca(2+)-dependent phosphoenzyme content; the total Ca2+ pump protein content was estimated by Western analysis of the immunoreactive Ca2+ pumps. We isolated RNA from fetal and adult hearts and estimated the SR Ca2+ pump mRNA content by Northern analysis. Ca2+ uptake and ATPase rates were significantly lower in the fetal and newborn SR membranes compared with the adult. The contents of active and total Ca2+ pump protein and of Ca2+ pump mRNA were 52-63% lower in the fetus than in the adult. These results indicate that a great deal of the slower sarcoplasmic reticulum Ca2+ uptake and ATPase rates in the fetal rabbit heart can be related to lower Ca2+ pump mRNA and protein contents. It is evident that transcriptional and/or posttranscriptional regulation of the SR Ca2+ pump may form an important part of the subcellular basis of the perinatal change in mammalian cardiac relaxation.
Animals↗
The role of dicarboxylic anion transport in the slower Ca2+ uptake in fetal cardiac sarcoplasmic reticulum.
Sarcoplasmic reticulum- (SR-)mediated Ca2+ transport is slower in the fetal heart compared with the adult. Virtually all previous studies of cardiac SR Ca2+ transport were performed in the presence of oxalate, a dicarboxylic anion that is cotransported with Ca2+ in skeletal muscle SR. If anion transport is developmentally regulated in cardiac SR, this could explain, in part, the previously reported results. The purposes of this study were to establish the presence of an SR dicarboxylic anion transport process in the rabbit heart and to determine if the perinatal changes in SR Ca2+ transport occur in a dicarboxylic anion-dependent and/or independent manner. In isolated fetal and adult rabbit cardiac SR membranes, we measured Ca2+ ATPase rates and 45Ca2+ uptake in the presence of the dicarboxylic anions maleate and succinate compared with the zwitterionic buffer PIPES, to which cardiac SR is essentially impermeable. We also measured 14C-succinate uptake by fetal and adult SR membranes. Anion-independent Ca2+ ATPase activity and net 45Ca2+ uptake were significantly lower in the fetal SR membranes than in the adult. Maleate and succinate increased the Ca2+ ATPase rates in the fetal and adult SR, but the effect was significantly greater in the adult. Maleate and succinate stimulated earlier attainment of maximal net Ca2+ uptake in the fetal and adult SR, suggesting that these dicarboxylic anions stimulated the rate of Ca2+ accumulation. Maleate and succinate significantly increased the maximal net Ca2+ uptake in the adult SR, but not in the fetus. The percentage of stimulation of Ca2+ uptake by maleate and succinate was similar in the fetal and adult SR.(ABSTRACT TRUNCATED AT 250 WORDS)
Animals↗
The future of behavioral pediatrics research: moving right along.
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Behavioral Medicine↗
This was your life: how your skeleton may be coaxed out of the cupboard.
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Bone Diseases↗
A familial MCA/MR syndrome due to translocation t(10;16) (q26;p13.1): report of six cases.
A minute familial translocation t(10;16) (q26;p13.1) was detected in a family with 6 affected children in 2 generations and 9 carriers in 3 generations. This apparently unique translocation is associated with a deleterious syndrome which includes fetal hydrops, ascites, complex congenital heart defect, psychomotor retardation, failure to thrive, hypotonia, narrow palpebral fissures, abnormally modeled, apparently low-set ears, cleft palate, thumb abnormalities, hypogenitalism, inguinal hernia, and sparse hair. All children of known or presumed carriers have been either balanced or unbalanced carriers of this translocation.
Abnormalities, Multiple↗
Scintigraphic measurement of regional gut transit in idiopathic constipation.
In this study, total gut transit and regional colonic transit in patients with idiopathic constipation were measured scintigraphically. Eight patients with severe constipation were studied, none of whom had evidence of abnormal function of the pelvic floor. 99mTc-radiolabeled Amberlite resin particles (average diameter, 1 mm; Sigma Chemical Co., St. Louis, MO) with a mixed meal were used to assess gastric emptying and small bowel transit; similar particles labeled with 111In were ingested in a coated capsule that dispersed in the ileocecal region. These were used to quantify colonic transit. Five healthy volunteers were also studied. Two patients showed delayed gastric emptying and two had slow small bowel transit. Seven of the eight patients had slow colonic transit. In five, delay affected the whole colon ("pancolonic inertia"); in two, transit in the ascending and transverse colon was normal, but solids moved through the left colon slowly. Mean colonic transit was also measured using radiopaque markers; this technique identified the patients with slow transit, as shown by measurements of overall colonic transit by simultaneous scintigraphy. However, estimated transit through the ascending and transverse colons was considerably shorter by the radiopaque marker technique. In conclusion, idiopathic constipation is characterized by either exaggerated reservoir functions of the ascending and transverse colons and/or impairment of propulsive function in the descending colon. Particle size may influence the result of regional colonic transit tests. Transit delays in other parts of the gut suggest that, in some patients, the condition may be a more generalized motor dysfunction.
Adult↗
Tropical spastic paraparesis/HTLV-1-associated myelopathy (TSP/HAM): treatment with an anabolic steroid danazol.
Tropical spastic paraparesis or HTLV-I-associated myelopathy is a progressive spastic disorder associated with the human T-lymphotropic virus type I. Some cases have responded to prednisone. Danazol is an attenuated androgen with minimal virilizing effects. It is used in the treatment of endometriosis and various autoimmune hematologic diseases shown to be responsive to prednisone. Because danazol is anabolic, useful in prednisone-responsive diseases, and less toxic than prednisone, we gave danazol to 6 patients with TSP and 1 with HIV, HTLV-I-associated myelopathy. Five patients had a favorable response. Two became ambulatory after having been confined to a wheelchair. Three were able to ambulate greater distances (in walkers) than prior to danazol. Three had noticeable decreases in spasticity. Urinary incontinence resolved in two. Physical therapy was variably employed in all except one patient. Two patients who had not responded to physical therapy responded to physical therapy and danazol. One patient did not tolerate danazol and one patient did not improve. Toxicities noted were mild elevations in liver enzymes in 4 patients; these responded to a decrease in dose of danazol; amenorrhea in one and mild fluid retention in one. We conclude that danazol is a useful agent in the management of TSP.
Adult↗
Treatment of anovulation due to polycystic ovarian syndrome by laparoscopic ovarian electrocautery.
Our experience of ovarian electrocautery for the treatment of polycystic ovarian syndrome (PCOS) in ten women is described. We found that nine responded favourably, either ovulating spontaneously or becoming more responsive to ovulation induction. There was a significant and persistent fall in serum testosterone levels, and a transient fall with subsequent rise in inhibin. We recommend that laparoscopic ovarian electrocautery is considered as an alternative to ovulation induction with gonadotrophins, in women with PCOS who fail to respond to clomiphene citrate.
Adult↗
Relative anti-inflammatory effect of oral dexamethasone-beta-D-glucoside and dexamethasone in experimental inflammatory bowel disease in guinea-pigs.
The relative anti-inflammatory effect of dexamethasone and a prodrug, dexamethasone-beta-D-glucoside, has been assessed in guinea-pigs with experimentally-induced inflammatory bowel disease (IBD). The glucoside prodrug is designed to reach the large intestine following oral administration. The active agent is liberated when the prodrug is hydrolysed by glycosidases of colonic bacteria. Guinea-pigs were administered degraded carrageenan in their drinking water to produce experimental IBD. Starting on day 15, dexamethasone (1.3 mumol kg-1) or dexamethasone-beta-D-glucoside (1.3 or 0.65 mumol kg-1) was administered by gastric intubation once daily for 5 days. Relative to control animals, the drug and prodrug treatments significantly (P less than 0.05) reduced the total number of caecal ulcers. While there was no difference statistically between the drug and prodrug treatments, the data suggest that a lower dose of dexamethasone, administered as its glucoside prodrug, could reduce side-effects without reduced efficacy. These results support the hypothesis that localized delivery of dexamethasone to the large bowel can improve pharmacotherapy of IBD by reducing the side-effects associated with corticosteroids.
Animals↗