The complete nucleotide sequence of an infectious clone of cauliflower mosaic virus by M13mp7 shotgun sequencing

We have determined the complete primary structure (8031 base pairs) of an infectious clone of cauliflower mosaic virus strain CM1841. The sequence was obtained using the strategy of cloning shotgun restriction fragments in the sequencing vector M13mp7. Comparison of the CM1841 sequence with that published for another caMV strain (Strasbourg) reveals 4.4% changes, mostly nucleotide substitutions with a few small insertions and deletions. The six open reading frames in the sequence of the Strasbourg isolate are also present in CM1841.

Tumor shedding and coagulation

Three syngeneic carcinomas from two species shed plasma membrane vesicles when cultured in vitro or grown in the ascites tumor form in vivo. Shed vesicles carry procoagulant activity that can account for the activation of the clotting system and the fibrin deposition associated with these and many other types of malignancy in animals and man.

Characterization of a vitamin D receptor knockout mouse as a model of colorectal hyperproliferation and DNA damage

The vitamin D receptor knockout (VDR-KO) mouse presents with a skeletal phenotype typical for complete lack of genomic 1,25-dihydroxycholecalciferol effects. Our previous data from human colorectal tissue suggest that the steroid hormone and its receptor may have protective function against tumour progression. In order to investigate the relevance of the vitamin D system for pre-malignant site-directed changes in the colon, we characterized the amount and site-specific distribution of the VDR along the large intestine in wild-type (WT), heterozygote (HT) and KO mice. We also evaluated expression of proliferating cell nuclear antigen (PCNA), of cyclin D1 and the levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker of oxidative stress. In colon ascendens, proliferative cells were dispersed all along the crypt and expression levels of all three markers were high in WT mice. A decrease of VDR expression did not affect expression significantly. In colon descendens, however, fewer proliferative cells were solely located in the lower third of the crypt, and an inverse relationship between VDR reduction, PCNA positivity and cyclin D1 expression was found in HT and KO mice. In parallel to enhanced proliferation a highly significant increase of 8-OHdG positivity occurred. Therefore, the sigmoid colon of VDR-KO mice, fed on an appropriate lactose/calcium-enriched diet to alleviate impaired calcium homeostasis-related phenotypic changes, is an excellent model for investigating induction and prevention of pre-malignant changes in one of the hotspots for human colorectal cancer incidence.

Effect of fasting on free and esterified carnitine levels in human serum and urine: correlation with serum levels of free fatty acids and beta-hydroxybutyrate

Serum levels of free L-carnitine, acylcarnitines, creatinine, beta-hydroxybutyrate, free fatty acids, cholesterol, triglycerides, and glucose were determined in healthy volunteers during a 24-36-hr fast. The effect of oral administration of free L-carnitine (1 g/person) on these parameters was studied. Urinary excretion of carnitine and creatinine was monitored throughout. Serum and urine levels of free carnitine and its renal clearance decreased during the fast. However, the serum concentration and urinary excretion of acylcarnitines increased during the same interval. Following the ingestion of free L-carnitine, both serum and urinary levels of free L-carnitine rose. Within 6 hr of ingestion, 10% of the administered dose could be accounted for by urinary excretion. No significant effect on the other serum constituents under study was seen following the oral L-carnitine dose. A significant negative correlation was found between serum levels of free L-carnitine and beta-hydroxybutyrate and free fatty acids (r equal -0.567, p less than 0.001 and r equal -0.607, p less than 0.001, respectively) during the fast.

Rapid diagnosis of Entamoeba infection by using Entamoeba and Entamoeba histolytica stool antigen detection kits

Humans are infected by two morphologically identical species of Entamoeba: Entamoeba histolytica causes amebic colitis and liver abscess, and Entamoeba dispar is noninvasive. Several weeks of culture and isoenzyme (zymodeme) analysis are required to differentiate E. histolytica from E. dispar. Here we report a field trial of commercial antigen detection kits designed to rapidly detect and differentiate E. histolytica from E. dispar in stool specimens. Stool specimens from 202 patients with diarrhea were examined for E. histolytica and E. dispar by microscopy, culture, and antigen detection. Compared with culture, microscopic identification of the E. histolytica-E. dispar complex was 60% sensitive and 79% specific, while the screening antigen detection test for the E. histolytica-E. dispar complex was 80% sensitive and 99% specific. Differentiation of E. dispar from E. histolytica by the E. histolytica-specific test was 95% sensitive and 93% specific compared with zymodeme analysis. We conclude that the antigen detection test for the E. histolytica-E. dispar complex is more sensitive and specific than microscopy and that the E. histolytica-specific antigen detection test is as reliable and much more rapid than zymodeme analysis for the differentiation of E. histolytica from E. dispar.

Entamoeba histolytica and Entamoeba dispar infection in children in Bangladesh

The prevalence of infection by the invasive parasite Entamoeba histolytica and the noninvasive parasite Entamoeba dispar was determined in 2000 children in Bangladesh. Antigen detection identified more cases of E. histolytica-E. dispar infection than did culture or microscopy. Microscopic identification of E. histolytica-E. dispar complex infection in stool did not equate with the diagnosis of amebic dysentery because most amebic infections in this population were due to E. dispar: Urban children with diarrhea had a 4.2% prevalence of E. histolytica infection and a 6.5% prevalence of E. dispar infection; rural asymptomatic children had a 1.0% prevalence of E. histolytica infection and a 7.0% prevalence of E. dispar infection. Shigella dysenteriae and Shigella flexneri infections were more frequent in children who also had Entamoeba infection, a potentially important consideration for the empiric treatment of dysentery in this population.

A double-blind placebo-controlled trial of progesterone vaginal suppositories in the treatment of premenstrual syndrome

Rigorous criteria were used to select women with severe premenstrual syndrome for inclusion in an 8-month double-blind placebo-controlled clinical trial of progesterone vaginal suppositories. Following a control month without treatment, progesterone (200 mg in polyethylene glycol base) or placebo was self administered twice daily by vaginal suppository for a minimum of 12 days before the onset of menstruation for 3 months. Crossover to the opposite medication for a further 3 months was followed by a final control cycle without treatment in month 8. Physician contact was minimized throughout the study to avoid any possible positive effects of psychological support which may have confounded past investigations. Detailed self-report questionnaires were completed every 3 days for the duration of the study. Although the attrition rate was high, 20 women completed the trial and their records are analyzed here. The results of this trial indicate that the response to vaginal progesterone in these dosages is, at best, marginal and not significantly different from response with placebo use.

Effect of litter size on plasma cholesterol and insulin and some liver and adipose tissue enzymes in adult rodents

Rats and mice were raised in litters of 4 or 14 per mother. Plasma levels of cholesterol and insulin were found to be elevated later in life in those raised in small litters. Hepatic 3-hydroxy-3-methylglutaryl-CoA reductase activity in rats was higher in large than in small litters on day 60 but not on day 240. In adipose tissue activity was higher in the small litters. The activities of phosphoenolpyruvate carboxy-kinase in liver and of fatty acid synthetase in adipose tissue were higher in large than in small litters later in life. It is concluded that early quantitative changes in food intake have permanent late effects.

Plasma carnitine levels during intravenous feeding of the neonate

The premature infant has a limited capacity for fatty acid oxidation. This study shows that solutions commonly used for intravenous feedings in the newborn infant contain no carnitine. Infants maintained on this solution have significantly lower total, free, and acylcarnitine levels as compared to when they are fed orally with expressed human milk or a proprietary formula, which is known to contain carnitine. The exogenous supply of carnitine to the premature infant may have a significant influence on the ability to stimulate optimal fatty acid oxidation.

Acetylcarnitine and free carnitine in body fluids before and after birth

The acetylcarnitine concentration in amniotic fluid fell significantly between 33 and 37 and 40 weeks of gestation. It was significantly higher in samples that had a low lecithin to sphingomyelin ratio. The acetylcarnitine content of tracheal fluid was higher in samples obtained from premature newborns. The major excretory form of carnitine is the acetate ester and only in adults does the urine contain significant amounts of free carnitine. The level of acetylcarnitine in plasma significantly increases after the first day of life; there was no difference in the plasma levels of carnitine between full-term and premature newborns. Plasma-free carnitine and acetylcarnitine levels were significantly lower in infants who were receiving a soybean-based formula. A positive correlation was found between the plasma level of ketone bodies and that of acetylcarnitine.

X-ray induction of methotrexate resistance due to dhfr gene amplification

The effect of ionizing radiation on methotrexate (MTX) resistance and gene amplification in cultured mammalian cells was investigated. X-irradiation of mouse EMT-6 cells induced cell killing and MTX resistance due to amplification of dihydrofolate reductase (dhfr) gene in a dose-dependent manner. The highest yields of mutant cells were obtained at approximately D37 (the dose at which 37% of the cells survive), where the frequency of MTX-resistant cells was four- to eightfold over that of the unirradiated population. The proportion of MTX-resistant cells among the survivors increased logarithmically with dose, up to a 1000-fold increase over unirradiated cells at 1000 cGy, the highest dose tested. The induced frequency of MTX resistance after X-irradiation was greater than the induced frequency of 8-azaguanine resistance, which indicates deletion of the hypoxanthine phosphoribosyltransferase gene. Inhibition of poly(ADP-ribose) polymerase by the addition of 3-aminobenzamide before irradiation increased both cell killing and MTX resistance. Metaphase spreads of chromosomes from EMT-6 cells that had been irradiated and subjected to stepwise increases in MTX concentration showed numerous double minutes. Pulsed-field gel electrophoresis of the DNA from cells containing radiation-induced double minutes showed that many copies of the dhfr gene were present on circular DNA molecules of 10(6), 2 x 10(6), and 3 x 10(6) base pairs. These results suggest a relationship between the induction of chromosome aberrations and the induction of gene amplification.

Quantitative analysis of the linkage between the interphalangeal joints of the index finger. An in vivo study

We have established a simple method of measuring joint motion under physiological conditions. For this purpose we use an ultrasound measuring system employing marker points consisting of miniaturized ultrasound transmitters. This device was tested on a simple biomechanical model, the linkage of the proximal and distal interphalangeal joints. The angles of these joints were recorded during opening and closing of the fist in 34 index fingers of 17 healthy persons. The results of the measurements were plotted on a rectangular coordinate system. Analysis showed an approximately linear linkage between the IP joints of the index finger. The curve for extension was the same as that for flexion. The linkage varies greatly. On average 1 degree of PIP joint flexion is equivalent to 0.76 degree of DIP joint flexion. Our study showed no significant difference between the dominant and non-dominant hand. The results showed that there is a linear linkage between the proximal and distal interphalangeal joints, which is equal for flexion and extension.

Clinical evaluation of chemomechanical caries removal in primary molars and its acceptance by patients

The purpose of this study was to evaluate the clinical efficiency and patient acceptance of the chemomechanical caries removal agent Carisolvtrade mark in deciduous teeth. Contralateral primary molars of sixteen 7- to 9-year-old patients (32 teeth) were treated with the air-motor and with Carisolv, respectively. Patients replied to a pre- and a postoperative questionnaire. Complete caries removal (CCR) was accomplished in all air-motor sessions. It was not achieved within the time limit of 15 min in 6 (37.5%) Carisolv sessions. Air-motor CCR time ranged between 6 and 18 s (mean: 11.81 s ). Carisolv CCR time, where accomplished within 15 min, ranged between 6 min 46 s and 13 min 57 s (mean: 6 min 51 s). Preoperatively, the majority of the children reported disliking the drilling, and that they would visit the dentist more often and prefer sitting in the chair longer if they could avoid it. Postoperatively, the majority of the children reported disliking the taste of Carisolv, estimated Carisolv to have taken longer, would not recommend it to their friends, and preferred the air-motor. In conclusion, Carisolv, although a step forward in terms of solution volume required, is not in a position to replace rotary instruments for caries removal: it did not remove decay completely in one third of our sample; it was much slower than the air-motor; it had a chlorine taste/odor our patients disliked.

Multiphasic MR imaging: a new method for direct imaging of pulsatile CSF flow

A new technique is described that allows for the creation of pure pulsatile flow magnetic resonance (MR) images in a single acquisition. Five to 16 electrocardiographically gated images spanning the entire cardiac cycle are obtained with use of a gradient-echo pulse sequence. The section can be varied from 4 mm thick to full thickness projection. Taken singly, each image provides direct assessment of flow direction and velocity. Subtraction of image pairs eliminates signal detected from stationary protons, producing images of pulsatile flow. In this study the technique was used to image the flow of cerebrospinal fluid (CSF) in healthy subjects and in one patient with syringohydromyelia. The data suggest that multiphasic MR imaging provides a powerful means for the noninvasive assessment of CSF pulsatile flow dynamics and may have potential clinical application for the investigation of a variety of abnormalities such as normal pressure hydrocephalus, syrinx, and spinal block.

Development of rat liver adenylcyclase

A developmental study of rat liver adenylcyclase and of its sensitivity to stimulation by adrenalin, glucagon, and NaF was carried out. During the last days of prenatal development, basal activity and hormone or NaF stimulated activity rise. Maximal levels are reached between day 2 and 10 after birth. Thereafter, adrenalin-stimulated adenylcyclase activity decreases considerably. In relation to basal activity, glucagon (and NaF) sensitivity increases with age while adrenalin sensitivity is sharply reduced after 10 days of age. These results may be related to changes in specific enzyme inducibility and/or carbohydrate metabolism known to occur in the course of development of rat liver. Additive hormonal stimulation was only observed in preparations obtained from animals which were at least 30 days of age.

Surface markers and transendothelial migration of dendritic cells from elderly subjects

Age-related changes of immune functions have been extensively investigated in both humans and animal models; nevertheless, the literature on potential alterations of dendritic cells, potent antigen presenting cells responsible for initiating immune responses, with aging is very scarce. We studied the immuno-phenotype of peripheral blood dendritic cells of elderly and young subjects by three-color flow cytometry. In addition, the capacity of transendothelial migration, an important step in inflammatory reactions, of peripheral blood dendritic cells of elderly subjects was investigated in an in vitro model. The expression of HLA-DR in the peripheral blood dendritic cells of the elderly subjects was significantly decreased when compared to the young control subjects. The expression of various other surface markers was similar in the young and elderly subjects. The ability of transendothelial migration of dendritic cells was found to be unimpaired in the elderly subjects. Both in the young and elderly subjects a significantly higher expression of CD29, CD86, HLA-DR, and HLA-DQ in the dendritic cells that had migrated through the endothelium in comparison to nonadherent, nonmigrating cells was found. In the migrating dendritic cells of the elderly subjects a significantly increased expression of CD11c was observed, whereas the expression of CD54 was significantly enhanced in the migrating dendritic cells of the young subjects only. In conclusion, our results demonstrate intact functions and a normal immunophenotype of dendritic cells derived from elderly subjects. Dendritic cells thus seem to be functional and therefore are not responsible for the well-known decline of T cell functions with aging.

Plasma carnitine in pregnancy

Plasma levels of total and free carnitine and acylcarnitine were determined in women pregnant for 28 to 42 weeks, and also in some of their fetuses. The finding was that the levels not only of free but also of total carnitine were very low in pregnancy. They were somewhat elevated in women with essential hypertension. Levels of acylcarnitine were significantly decreased in gestational diabetics, presumably because these women were treated with insulin. In nine cases examined, plasma levels of total and free carnitine and acylcarnitine were significantly higher in the fetuses than in their mothers.

Influence of resin cement viscosity on microleakage of ceramic inlays

OBJECTIVES

The aim of the present investigation was to evaluate the effect of the different viscosities of two resin luting cements on microleakage of ceramic inlays at dentinal margins. The effect of the width of the space between inlay and tooth, on the quality of the marginal seal was also investigated.

METHODS

Mesial and distal class V cavities were prepared in 48 extracted third molars. The incisal margins of the cavities were in enamel and the cervical margins in dentin. Subsequently, Empress inlays with different cervical margin gap dimensions were fabricated. The mean cervical gap dimensions in the respective groups were as follows: group 1 (27 microm); group 2 (232 microm); group 3 (406 microm). Half the inlays in each group (16) were cemented with a low viscous resin luting cement, and half (16) with a highly viscous resin luting cement. The teeth were subjected to occlusal loading with synchronized thermal cycling in a masticatory simulator. Then, the specimens were immersed in basic fuchsin solution, and dye penetration along the cavity walls was measured. In addition, marginal adaptation was analyzed in the SEM at baseline and after loading, using a replica technique.

RESULTS

With regard to dye penetration at dentinal margins, the highly viscous cement performed statistically significantly better at dentin/composite margins than the low viscous cement (p=0.0158). These findings are supported by SEM analysis.

SIGNIFICANCE

It is assumed that polymerization stress within the luting cement could not be completely compensated for by larger luting spaces. Highly viscous luting cements are recommended for cementing class V inlays in larger luting spaces.