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Granulosis viruses, with emphasis on the GV of the Indian meal moth, Plodia interpunctella.

The granulosis viruses and nuclear polyhedrosis viruses are being considered for use as biological insecticides for control of their insect hosts. Many of these insect species, which include some of the most serious pests of agriculture and forests, have become difficult to control because they have developed resistance to chemical insecticides. Several laboratory and field studies have demonstrated that the baculoviruses (GV and NPV) are promising alternatives to chemicals for the control of economically important insects. These viruses are highly virulent, selective, and stable, and the impact on the environment following their application is minimal. A decision concerning the application of baculoviruses to stored grain and field crops must be based upon a prudent consideration of the benefits to be obtained and the potential risks of their use. Such decisions should be made only after consideration of the physical, chemical, and biological properties of these viruses. In addition, methods must be developed for the unequivocal identification of these viruses, and their effects on nontarget species at the cellular and molecular levels must be investigated. This can best be accomplished if a sufficient body of knowledge regarding the molecular properties of these viruses and their infection process is accumulated by an extensive quantitative approach. Much of this knowledge is lacking because, prior to their consideration for use as insecticides, the baculoviruses appeared to have little medical or economic importance. As a result, interest in studying them was limited. It has become obvious that the molecular properties of these viruses must be investigated if full advantage is to be taken of using them as insect control agents, and if present and future problems concerning their use as insecticides are to be handled properly. Fundamental research on the biochemical and biophysical properties of baculoviruses has concentrated mainly on a variety of nuclear polyhedrosis viruses (Harrap, 1972a,b; Harrap et al., 1977; Summers and Smith, 1975a,b; Arif and Brown, 1975). Much of this progress can be attributed to tissue culture-host cell systems available for the NPVs. The in vitro host system(s) has allowed insect virologists to make phenomenal strides in understanding the cellular and molecular events of virus infection, and, in addition, to enter the era of biochemical sophistication in which animal virology is found at present.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

The obsolescent renal glomerulus--collapse, sclerosis, hyalinosis, fibrosis. A light- and electron microscopical study on human biopsies.

By light and electron microscopical examination it is shown that four structural components can contribute to obsolescent glomeruli: capillary basement membranes, enriched mesangium matrix, "vascular" hyalin and collagen fibers. Each of these components can bring about glomerular damage alone. One non-reactive form--a glomerular collapse with only basement membrane remnants--can be separated from three reactive forms: the accumulation of mesangium matrix (sclerosis or matrix-sclerosis), deposition of vascular hyalin (hyalinosis in the narrow sense), and fiber development within the former urinary space (fibrosis or fibro-sclerosis). The use of the term "fibrinoid" in place of the descriptive term "hyalin" is not supported by objective results. Knowledge of the various constituents which accumulate in the reactive types of glomerular obsolescence might be important in the diagnosis of the underlying disease, though mixed pictures were often observed. To avoid terminological overlap we suggest that the term "hyalinization" is replaced by "obsolescence" or "scarring" with specification of the structural components involved.

Adult↗

Oral health-related knowledge, attitudes, and beliefs among 11 to 12-year-old Finnish schoolchildren with different oral health behaviors.

The aim of this study was to explore oral health-related knowledge, attitudes, and beliefs among 11 to 12-year-old schoolchildren with favorable, moderate, or poor behavior related to oral health. The data were gathered by questionnaire. Recommendations commonly used in Finland in oral health education were chosen as the criteria for selection of groups of children with favorable, moderate, and poor oral health behavior. Differences between groups were analyzed using crosstabulations and factors related to unfavorable behavior using logistic regression analysis. The percentage of children with appropriate knowledge was higher in the good behavior group (GB) than in the other groups. The groups differed most in the children's knowledge of the recommendation to use fluoride toothpaste at least twice a day. Most children in the GB group considered it important to brush their teeth for the fresh feeling this gave. The majority of children in all groups considered it important to brush their teeth when going to the dentist. The majority also considered brushing important for avoiding tooth decay and tooth discoloration as well as for having fresh breath. Unfavorable knowledge, attitudes, beliefs, and behavior tended to accumulate in the same children. Factors associated with unfavorable behavior were male sex, mother's low skill occupation level, and child's poor knowledge of oral health-related facts.

Attitude to Health↗

Immunotherapy. Neuroblastoma as a model.

Combinations of aggressive therapy and radiotherapy directed at the primary tumor site as well as dose intensive chemotherapy against metastases can effectively induce complete remissions in patients with stage IV neuroblastomas. By virtue of its tumor specificity, the use of immunotherapy at the time when microscopic residual disease is present holds great promise in eradicating the tumors permanently. Monoclonal antibodies can accumulate selectively and at high concentrations in neuroblastomas. They have the potential of initiating complement activation and inflammation at the tumor site. Hematopoietic factors and cytokines can reinforce the body with tumoricidal leukocytes. Ex vivo activation of autologous white cells as well as arming by genetic manipulation can also produce tumor-seeking vehicles that may be therapeutically useful. As the knowledge of tumor and host immunobiology accumulates, the optimal combination of these approaches will become apparent.

Antibodies, Monoclonal↗

Accumulation of 8-hydroxydeoxyguanosine and its relationship with antioxidant parameters in patients with Eales' disease: implications for antioxidant therapy.

PURPOSE: Eales' disease (ED) is an idiopathic retinal inflammatory disease, which affects the retina of young adult males. Oxidative stress has been associated with the development of various inflammatory diseases. Accumulation of DNA oxidation products has been considered as an early biomarker for assessing oxidative tissue damage. To our knowledge there are no human clinical reports available on the accumulation of DNA adducts in ocular inflammatory diseases. Hence the aim of the present study was to determine the levels of 8-hydroxy-2'deoxyguanosine (8-OHdG) and to correlate it with the antioxidant and oxidant parameters in patients with ED and healthy control subjects. METHODS: Twenty-two patients with ED [12 in active perivasculitis (AV) and 10 in healed vasculitis stages (HV)] were recruited for the study. 14 healthy volunteers were included as control. 8-OHdG was determined in their leukocytes by Gas chromatography-Mass Spectrometry (GC/MS) technique. Glutathione levels were determined in plasma, while Superoxide dismutase (SOD) activity and thiobarbituricacid reactive substances (TBARS) content were determined in their erythrocytes. RESULTS: Our results indicated that 8-OHdG levels were elevated by 3 and 1.9 folds respectively in AV and HV stages of patients with ED, when compared with healthy control subjects. Increased 8-OHdG levels correlated with diminished SOD activity and decreased GSH content in patients with ED. CONCLUSIONS: To our knowledge, this is the first report of DNA adduct accumulation in patients with ED. Increased DNA adduct accumulation correlated with the severity of the disease, and they lie in parallel with diminished antioxidant capacity observed in patients with ED. Based on the observations from our present work and our earlier studies, we reiterate that oxidative stress is involved in the disease process. Hence we believe antioxidant vitamin E and C supplementation might be beneficial to patients with ED.

8-Hydroxy-2'-Deoxyguanosine↗

[Cerebral kinetics of brain perfusion agents].

Radiotracers called chemical microsphere are widely accepted as brain perfusion agents. Following the intravenous administration, these drugs are transported via the artery to the brain, cross the intact blood-brain barrier, and enter the brain tissue. Once the tracer flows into the brain, the efflux of the tracer is prevented by some trapping mechanism, resulting in prolonged retention. Because the distribution of the accumulated tracer remains approximately consistent with regional cerebral blood flow for a relatively long period, high-quality SPECT images reflecting the distribution pattern of cerebral blood flow can be acquired. However, unlike true microsphere, cerebral kinetics of the brain perfusion agents is complicated, and various causes may produce discrepancy between the distributions of the tracer and blood flow. In this review, cerebral kinetics of the brain perfusion agents used commonly is discussed. The knowledge of the mechanism of brain accumulation appears to be essential to appropriately determine the tracer of choice and interpret the obtained images.

Amphetamines↗

Metal resistance and accumulation in bacteria.

Recent research on the ecology, physiology and genetics of metal resistance and accumulation in bacteria has significantly increased the basic understanding of microbiology in these areas. Research has clearly demonstrated the versatility of bacteria to cope with toxic metal ions. For example, certain strains of bacteria can efficiently efflux toxic ions such as cadmium, that normally exert an inhibitory effect on bacteria. Some bacteria such as Escherichia coli and Staphylococcus sp. can volatilize mercury via enzymatic transformations. It is also noteworthy that many of these resistance mechanisms are encoded on plasmids or transposons. By expanding the knowledge on metal-resistance and accumulation mechanisms in bacteria, it may be possible to utilize certain strains to recover precious metals such as gold and silver, or alternatively remove toxic metal ions from environments or products where their presence is undesirable.

Journal Article↗

Reflection and patterns of knowing in nursing.

Over the last decade nursing has progressed from a reliance on empirical theory applied to practice to a recognition that experience develops knowledge that can guide the actions of practitioners. Reflection is a means of surfacing experiential knowledge, and students may begin to use reflection as their experience of nursing accumulates. As Carper was a key figure in widening that knowledge accepted as knowing in nursing beyond the empirical, it is both justified and recommended that her work should be incorporated into reflective practice. Johns has integrated Carper's work in his model of guided reflection and this paper briefly examines this combination. The main focus is on two further patterns of knowing: unknowing and sociopolitical knowing. These patterns are examined and the contribution they could make to reflective practice is discussed.

Education, Nursing, Continuing↗

Extraosseous accumulation of 99mTc-MDP in a benign intrapulmonary calcified focus.

A patient with a benign calcified pulmonary focus concentrating 99mTc-methylenediphosphonate is described. To the best of our knowledge, this is the first description of the accumulation of 99mTc-phosphate compounds in a benign calcified focus of the lung. The value of a routine correlation with X-ray study in every case of focal chest concentration of 99mTc-MDP is emphasized.

Bone and Bones↗

Aspergillus niger citric acid accumulation: do we understand this well working black box?

This Mini-Review summarizes the current knowledge on the biochemical and physiological events leading to massive citric acid accumulation by Aspergillus niger under industrially comparable conditions, thereby particularly emphasizing the roles of glycolytic flux and its control, excretion of citric acid from the mitochondria and the cytosol, and the critical fermentation variables. The potential of novel techniques for metabolic analysis and genomic approaches in understanding this fermentation is also discussed.

Aspergillus niger↗

Metallic foreign bodies in the stomach.

We present a case of a patient who ingested 648 metallic objects that formed an intertwining mass within the stomach, requiring operative removal. Of interest was the absence of symptoms and complications after 11 years of continual ingestion. To our knowledge, this is the second heaviest accumulation of metallic foreign objects removed from the stomach of a living patient.

Adult↗

Recent advances on bioactive natural products from Chinese medicinal plants.

China has accumulated a rich body of empirical knowledge of the use of medicinal plants for the treatment of various diseases throughout its long history. Chemical studies on Chinese medicinal plants provide a valuable material base for the discovery and development of new drugs of natural origin. In this article recent chemical work on various Chinese medicinal plants is reviewed, including Mussaenda pubescens (Rubiaceae), Isatis indigotica (Cruciferae), Euphorbia fischeriana, and E. ebracteolata (Euphorbiaceae), and Stemona species (Stemonaceae). The structural diversity of the medicinal chemical constituents of the above plants is discussed.

Animals↗

Opportunities for bioactive compounds in transgenic plants.

A variety of bioactive compounds have now been introduced into plants through recombinant DNA techniques. Early examples included genes encoding proteins conferring herbicide tolerance and insect or virus resistance. More recently, pharmacologically useful compounds such as enkephalin and immunoglobulin have been produced in transgenic plants. Modification of existing compounds to provide better nutritional value or improved functional properties is exemplified in the case of seed storage proteins. The value of RNAs as bioactive compounds for suppression of undesirable products and viral infection has now been demonstrated in plants. The developmentally regulated expression of novel bioactive compounds in defined tissues, and their targeting to specific subcellular locations, is becoming of ever increasing economic and sociological importance as knowledge of the molecular mechanisms involved accumulates.

Endopeptidases↗

Metabolic engineering of sugar catabolism in lactic acid bacteria.

Lactic acid bacteria are characterized by a relatively simple sugar fermentation pathway that, by definition, results in the formation of lactic acid. The extensive knowledge of traditional pathways and the accumulating genetic information on these and novel ones, allows for the rerouting of metabolic processes in lactic acid bacteria by physiological approaches, genetic methods, or a combination of these two. This review will discuss past and present examples and future possibilities of metabolic engineering of lactic acid bacteria for the production of important compounds, including lactic and other acids, flavor compounds, and exopolysaccharides.

Biological Transport↗

Neural circuitry of judgment and decision mechanisms.

Tracing the neural circuitry of decision formation is a critical step in the understanding of higher cognitive function. To make a decision, the primate brain coordinates dynamic interactions between several cortical and subcortical areas that process sensory, cognitive, and reward information. In selecting the optimal behavioral response, decision mechanisms integrate the accumulating evidence with reward expectation and knowledge from prior experience, and deliberate about the choice that matches the expected outcome. Linkages between sensory input and behavioral output responsible for response selection are shown in the neural activity of structures from the prefrontal-basal ganglia-thalamo-cortical loop. The deliberation process can be best described in terms of sensitivity, selection bias, and activation threshold. Here, we show a systems neuroscience approach of the visual saccade decision circuit and the interaction between its components during decision formation.

Animals↗

[New aspects of diabetes].

Type II diabetes is a serious, insidious disease which is growing at an impressive rate, with 200 million diabetics worldwide and as many who ignore their state. Having been seriously studied over more than a century and a half, an enormous quantity of knowledge regarding this disease has been accumulated. The research we are conducting has allowed us to identify the most important actors responsible for diabetes. These are glucose which leads to glyoxal and to methylglyoxal which in turn reacts with innumerable targets in the organism (including insulin) unless prevented from doing so by detoxifying mechanisms (e.g., glyoxalases). The role of microorganisms in the occurrence and development of diabetes has also to be seriously examined.

Animals↗

Vasopressin-induced cytoplasmic and nuclear calcium signaling in cultured cortical astrocytes.

We sought to determine whether vasopressin V(1a) receptor (V(1a)R) mRNA detected in cortical astrocytes [Brain Res. Mol. Brain Res. 45 (1997) 138] was translated into functional receptors by investigating the effector calcium signaling cascade associated with the vasopressin V(1a) receptor subtype. Analysis of intracellular calcium dynamics using the calcium-sensitive dye fura-2 AM indicated that exposure of cortical astrocytes to V(1) vasopressin receptor agonist, [Phe(2),Orn(8)]-oxytocin, induced a marked dose-dependent increase in intracellular calcium which was abolished by depletion of extracellular calcium. V(1) agonist treatment induced a rapid increase in calcium signal in both the cytoplasm and nucleus, which was followed by an accumulation of the calcium signal in the nucleus, suggesting translocation of cytoplasmic calcium into the nucleus. The nuclear calcium signal was sustained for several seconds followed by translocation back to the cytoplasm. Following the nuclear-to-cytoplasmic calcium translocation, total free intracellular calcium concentration decreased. The dynamic calcium cytoplasmic and nuclear localization was confirmed by laser scanning confocal microscopy coupled with the calcium-sensitive dye fluo-3 AM. To determine the source of calcium, V(1) agonist-induced (45)Ca(2+) uptake and [(3)H]IP(1) accumulation were investigated. V(1) agonist induced significant and rapid uptake of (45)Ca(2+) and a significant dose-dependent increase in [(3)H]IP(1) accumulation in cortical astrocytes. To our knowledge, this is the first documentation of a vasopressin receptor-induced calcium signaling cascade in cortical astrocytes and the first documentation of vasopressin receptor induction of nuclear calcium signaling.

Animals↗

Identification of quercetin 3-O-beta-D-glucuronide as an antioxidative metabolite in rat plasma after oral administration of quercetin.

The potential beneficial effect of dietary quercetin (3,3',4',5,7-pentahydroxyflavone) has attracted much attention in relation to the prevention of cardiovascular disease. It is generally recognized that dietary quercetin is subject to metabolic conversion resulting in conjugated forms during absorption and circulation. However, no quercetin conjugates have yet been identified from biological fluids or tissues. In the present study, we isolated and characterized two quercetin conjugates from the plasma of quercetin-administered rats. The blood plasma was collected from 26 rats 30 min after oral administration of quercetin (250 mg/kg body weight), concentrated, dissolved in 2% acetic acid aqueous solution (pH 2.65), and extracted with ethyl acetate. Two compounds (P2, P3) were obtained from the extract by repeated reversed-phase HPLC. On the other hand, two quercetin glucuronides were synthesized chemically and identified as quercetin 3-O-beta-D-glucuronide (Q3GA) and quercetin 4'-O-beta-D-glucuronide (Q4'GA), as determined from FABMS, 1H- and 13C-NMR, and HMBC data. The retention times of P2 and P3 in the HPLC chromatogram corresponded to those of Q3GA and Q4'GA, respectively. FABMS data demonstrated that P2 and P3 are quercetin monoglucuronides. 1H-NMR data for P2 were completely in agreement with those for Q3GA. P2 was therefore identified as Q3GA. This is, to our knowledge, the first evidence that Q3GA accumulates in vivo after oral administration of quercetin. Q3GA is likely to act as an effective antioxidant in blood plasma low-density lipoprotein, because this conjugated metabolite was found to possess a substantial antioxidant effect on copper ion-induced oxidation of human plasma low-density lipoprotein as well as 1,1-diphenyl-2-picrylhydrazyl radical-scavenging activity.

Administration, Oral↗