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J R Carlson

Publications and source records attributed to J R Carlson.

At least 55 records · Page 3Linked to original sources
PubMed1996

Male-male courtship behavior induced by ectopic expression of the Drosophila white gene: role of sensory function and age.

Male-male courtship behavior was recently reported to be induced in large populations of Drosophila (e.g., 600-1500 flies) by ectopic expression of the white (w) gene. Little is known about the basis of this behavior; in male-female courtship, sensory cues are believed to play an important role. Previous data are consistent with the possibility that misexpression of w causes abnormal reception or processing of sensory information. We show here that w-induced male-male courtship occurs in isolated pairs of flies. Thus the behavior does not depend on sensory cues found only among large populations of flies, or on cues produced only by a small subset of such populations. This finding enabled quantitative analysis of mechanisms that underlie the behavior. Specifically, male-male courtship does not depend on the reception of olfactory information, nor on the reception or generation of auditory cues, as determined by surgical ablation of antennae, maxillary palps, or wings. Although the rapid onset of the behavior following w induction suggested that its basis could lie in a modulation of sensory physiology, we found visual, olfactory, and gustatory function to be normal in physiological or behavioral tests. The only sensory deprivation to produce an effect on male-male courtship was testing under dim red light; the percentage of flies courting another male was reduced to one-fourth of control values. A striking age dependence of the behavior is also documented: courtship between paired male mini-w+ flies was not observed in tests of very young (1-day-old) flies, but occurs at high levels between the ages of 1 and 4 weeks.

Aging↗
PubMed1996

Genetic and molecular studies of olfaction in Drosophila.

Drosophila melanogaster, an insect amenable to convenient molecular and genetic manipulation, has a highly sensitive olfactory system. A number of Drosophila olfactory mutants have been isolated and characterized. The smellblind mutant has a defect affecting a voltage-gated Na+ channel. The norpA mutant, defective in a phospholipase C, has a reduced response to odorants in one type of olfactory organ, providing genetic evidence for use of the inositol-1,4,5-trisphosphate signal transduction pathway in olfaction. Since the norpA gene is also required for phototransduction, this work demonstrates overlap in the molecular genetic basis of vision and olfaction. Interestingly, genetic analysis indicates that some olfactory information flows through a pathway which does not depend on norpA. Some mutants, such as ptg, acj6 and Sco, show odorant specificity, in the sense that some odorant responses are greatly reduced, whereas others are little affected, if at all. Some, but not all, mutations affect both larval and adult olfactory responses. Two tightly-linked Drosophila genes encode homologues of moth pheromone-binding proteins (PBPs). Genetic analysis may help determine whether PBPs facilitate transit of pheromones to or from olfactory receptor neurons. Information from Drosophila could be useful in designing means of controlling mosquitoes. It may also be possible to study olfactory genes, such as those encoding PBPs, from other insects by mutating them, introducing them into Drosophila and analysing their function in vivo.

Amino Acid Sequence↗
PubMed1996

Olfaction in Drosophila: from odor to behavior.

Odors elicit a variety of behavioral responses from Drosophila via a relatively simple, but sensitive, olfactory system. An increasing number of mutants have been found to be defective in olfactory function. Genetic and molecular analyses of the Drosophila olfactory system have identified some of its molecular components, and have revealed some principles of its function and organization.

Animals↗
PubMed1996

MF59 adjuvant enhances the immunogenicity of influenza vaccine in both young and old mice.

The responses of young (8 week) and old (18 month) mice to influenza vaccine with and without the potent emulsion adjuvant MF59 were compared. In influenza naive mice, vaccine-specific antibody and T-cell proliferation were significantly lower in the old group compared to the young group. Post-immunization cytokine levels and antibody isotype profiles were different in the old compared to the young mice. The addition of the adjuvant MF59, a submicron oil-in-water emulsion composed of 5% v/v squalene, 0.5% v/v Tween 80 and 0.5% v/v Span 85, significantly increased the immune responses of both the young and old naive mice to the vaccine. The responses of the old mice given adjuvant increased to levels equivalent to those of young mice with vaccine alone. In mice previously infected with influenza virus, similarly depressed immune responses to vaccination were detected in the old mice. While the addition of MF59 to the vaccine had little effect on antibody titres of the previously infected young mice, the adjuvant significantly increased the antibody responses of the previously infected old mice. These results suggest that influenza vaccine combined with MF59 may significantly improve immune responses of elderly humans to influenza vaccination.

Adjuvants, Immunologic↗
PubMed1996

Identification of beta-glucuronidase-resistant diastereomeric glucuronides of 3-hydroxy-3-methyloxindole formed during 3-methylindole metabolism in goats.

Goats were jugularly infused with the pneumotoxin 3-methylindole (3MI; 15 mg/kg, 0.5 microCi/kg) dissolved in cremophor-EL to characterize the urinary metabolites of 3MI in a ruminant specie. Urine was collected for 36 hr after the beginning of a 2-hr infusion period, and 3MI metabolites were purified using reversed-phase HPLC. Goats excreted 3MI as at least 11 distinct metabolites. Metabolites were characterized using a combination of UV spectroscopy, 1H- and 13C-NMR spectroscopy, and negative-ion FAB/MS. Two of the metabolites (E1 and E2), representing approximately 30% of the urinary radioactivity, were unambiguously identified as diastereomeric glucuronides of 3-hydroxy-3-methyloxindole [HMOI; 3-(beta-D-glucosiduronic acid)-3-methyloxindole]. Glucuronide conjugates were investigated using enzymatic and chemical hydrolysis. These ethereal glucuronides were unique in that they were not readily hydrolyzable with bovine beta-glucuronidase, although one of the diastereomers was hydrolyzed sparingly by beta-glucuronidase from Helix pomatia. Treatment of the glucuronides with 6 M HCI for a 2-hr period liberated unconjugated HMOI. Treatment of each diastereomer with dilute acid (pH 3) or dilute alkali (pH 10) was ineffective at hydrolyzing the conjugates. Goats form HMOI from 3MI and extensively glucuronidate the metabolite before excreting it, as opposed to mice that do not conjugate HMOI before excretion. These ethereal glucuronic acid conjugates seem to be unique in that they are essentially resistant to beta-glucuronidase-catalyzed hydrolysis.

Animals↗
PubMed1996

Rehabilitation and social and adaptive development of young renal transplant recipients.

OBJECTIVE: To survey a group (n = 37) of children and adolescents, who had received renal transplants, along with a parent, to determine their rehabilitation status and social and adaptive development. Additionally, subjects were asked to identify factors perceived as interfering with development and rehabilitation. DESIGN: This primarily descriptive study used a comparative data analysis strategy. There was also an exploratory component to the study. SAMPLE/SETTING: Potential subjects included all children more than 5 and less than 21 years of age who had received at least one renal transplant at a large university medical center in the Midwest. Subjects' actual ages were 5 to 20 (mean = 13.1); 14 were female, 23 were male. Twenty-five had a functioning transplant at the time of the study. METHODS: Telephone interviews were conducted with the child and a parent. The Vineland Adaptive Behavior Subscales for communication, daily living skills and socialization were administered. RESULTS: The mean communication score was 86.5 (19th percentile), mean daily living skills score was 88.1 (21st percentile), and the mean socialization score was 89.0 (23rd percentile). There was no significant difference on any domain score by whether or not the child had a functional transplant at the time of the study. Factors reported by child and parent as interfering with age-appropriate activities were explored. CONCLUSIONS: Nurses working with children and adolescents who have received renal transplants have many opportunities to incorporate developmental assessments and interventions into their nursing care to help these children to lead fuller and more satisfying lives.

Activities of Daily Living↗
PubMed1995

Concordance of PCR and antibody results from HIV testing of injecting drug users.

Standard HIV-1 testing relies on the enzyme immunoassay (EIA) for detecting antibodies specific to HIV-1. This technique may misclassify persons as HIV-1-negative in instances where testing follows infection but precedes development of antibody to HIV-1. To evaluate the occurrence of HIV infection in the absence of positive antibody, polymerase chain reaction (PCR) for viral DNA in the blood has been applied. Research comparing these two testing techniques has generally focused on populations of homosexual and bisexual men. This study compares PCR and antibody testing of 337 injecting drug users recruited from street settings in San Francisco. Of 286 HIV-1 antibody-negative samples, 3 (1.0%) were PCR-positive. Of 49 HIV-1 antibody-positive samples, 1 (2.0%) was PCR-negative. Two samples were antibody-indeterminate and PCR-negative. This yielded an overall concordance of 331/335 (98.8%), excluding the indeterminate results. These results suggest that current antibody methodology is adequate. However, misclassification among recently infected individuals may occur, which is of concern in high-incidence groups.

Adult↗
PubMed1995

Requirement for a phospholipase C in odor response: overlap between olfaction and vision in Drosophila.

A central problem in sensory system biology is the identification of the signal transduction pathways used in different sensory modalities. Genetic analysis of transduction mutants provides a means of studying in vivo the contributions of different pathways. This report shows that odorant response in one olfactory organ of Drosophila melanogaster depends on the norpA phospholipase C (EC 3.1.4.3) gene, providing evidence for use of the inositol 1,4,5-trisphosphate (IP3) signal transduction pathway. Since the norpA gene is also essential to phototransduction, this work demonstrates overlap in the genetic and molecular underpinnings of vision and olfaction. Genetic and molecular data also indicate that some olfactory information flows through a pathway which does not depend on norpA.

Animals↗
PubMed1995

Scutoid mutation of Drosophila melanogaster specifically decreases olfactory responses to short-chain acetate esters and ketones.

A molecular-genetic approach has been taken to identify genes involved in olfactory transduction in Drosophila melanogaster. Two independent lines of research led to the finding that the dominant Scutoid (Sco) mutation causes a diminished extracellular electroantennogram response to the odorants ethyl acetate (EtAC) and acetone (AC). Sco flies showed about 4- and 2.5-fold reduced responses to EtAC and AC, respectively, compared to Canton-S wild-type and sibling control flies lacking the Sco mutation when electroantennogram recordings were made from the proximal anterior third antennal segment. The responses to five other odors from three different chemical classes were unaltered. The maximum response to either EtAC or AC was decreased with no change in apparent affinity. Responses to short-chain (but not long-chain) acetate esters and ketones were dramatically affected at all antennal locations tested. Only in the proximal quadrants were responses to ethyl acetoacetate also reduced. Most Sco revertants tested had a normal olfactory response; duplications of the region including no-ocelli partially suppress the Sco bristle as well as olfactory phenotypes. Sco adults had an impaired behavioral response to EtAC but not to banana or propionate. There was no effect of the mutation on larval chemosensory behavior or extracellularly recorded adult compound eye and ocellar visual responses. These findings suggest the involvement of Sco in an olfactory pathway in adults which is specific for short-chain acetate esters and ketones.

Acetates↗
PubMed1995

The olfactory and visual systems are closely related in Drosophila.

The olfactory and visual systems of Drosophila have similar developmental origins: both derived from the eye-antennal imaginal disc. Moreover, there are commonalities in the cellular, molecular, and genetic underpinnings of their development. For example, the developmental program of both systems entails cell death, which depends upon the irregular chiasm C-roughest gene, and both systems require the lozenge gene for normal pattern formation. The rdgB (retinal degeneration B) gene is required not only for the maintenance and physiology of the visual system, but also for olfactory physiology. This gene has been shown by others to encode a phosphatidylinositol transfer protein; it is expressed both in visual and olfactory organs. The norpA gene, which encodes a phospholipase C, is also required both for phototransduction and for odorant response in one olfactory organ. Thus some genes are required in both systems; in addition, at least one olfactory gene that is apparently not expressed in the visual system may have a visual system counterpart. These and other similarities are considered in terms of the evolutionary relationship between the two systems. We conclude that analysis of the visual system is likely to provide insight into the development and function of the olfactory system, and vice versa.

Animals↗
PubMed1994

Systemic cytokine profiles in BALB/c mice immunized with trivalent influenza vaccine containing MF59 oil emulsion and other advanced adjuvants.

We have studied serum cytokine profiles in BALB/c mice after immunization with influenza vaccine alone or combined with the following adjuvants: alum; MF59 emulsion; MF59 containing the muramyl peptide N-acetyl-muramyl-L-alanyl-D-isoglutaminyl-L-alanine-2-(1,2- dipalmitoyl-sn-glycero-3-(hydroxyphosphoryloxy)) ethylamide (MTP-PE); MF59 plus the lipid A analogue monophosphoryl lipid A; MF59 plus the Quil A saponin fraction LTC; or LTC alone. Pooled mouse sera were analyzed by ELISA at various times after immunization for IL-1 alpha, IL-2, IL-3, IL-4, IL-5, IL-6, IL-10, IFN-gamma, and TNF-alpha. In naive mice, vaccine alone induced low levels of IL-3 and IL-5 only; vaccine plus alum induced a low IL-6 response as well. The MF59-based adjuvants significantly increased the IL-5 and IL-6 levels, whereas Quil A LTC induced strong IFN-gamma and measurable IL-2 responses, in addition to moderate IL-5 and IL-6. In previously infected mice, MF59 and MF59/MTP-PE were capable of generating IFN-gamma responses, as well as IL-5 and IL-6. All of the cytokine responses were rapid (peaking 3 to 12 h postimmunization) and short lived. In naive mice, the MF59 adjuvants induced serum cytokine profiles that are consistent with a primarily Th2-type response, whereas the Quil A LTC induced cytokines associated with both Th1 and Th2 responses. Ab analyses indicated that, although the adjuvants strongly affected the magnitude of the humoral response, there was no obvious correlation between the cytokine profile observed and the subclasses of Ab induced.

Adjuvants, Immunologic↗
PubMed1994

Putative Drosophila pheromone-binding proteins expressed in a subregion of the olfactory system.

Four genes expressed in the olfactory system of Drosophila melanogaster have been identified by subtractive hybridization. Two of these genes, OS-E and OS-F, are related to genes encoding moth pheromone-binding proteins. The OS-E and OS-F genes are tightly linked and are expressed in a subregion of the antenna (the primary olfactory organ). A protein sequence analysis suggests the possibility that pheromone-binding proteins are members of a larger class of proteins, extending beyond the olfactory system. The predicted product of a third gene, OS-D, shares features common to vertebrate odorant-binding proteins, but has a primary structure unlike odorant-binding proteins. The fourth gene, OS-C, encodes a novel 13-kDa protein that contains a putative nuclear import sequence and an acid-rich region. The expression patterns of these genes differ within the antenna; their transcript distributions support the notion of specialized roles for different olfactory sensilla. The functions of the OS gene products have not been demonstrated; however, the potential identification of pheromone-binding proteins in Drosophila, a species with well characterized genetics, may offer a means of analyzing the function of these molecules that is not available in other systems.

Amino Acid Sequence↗
PubMed1994

Olfactory physiology in the Drosophila maxillary palp requires the visual system gene rdgB.

We describe the kinetics of odorant response in the maxillary palp of Drosophila, and show that the rate of recovery from odorant stimulation is affected by mutation of the rdgB (retinal degeneration B) gene. We use immunocytochemistry to confirm that the rdgB gene product is expressed in the maxillary palp. rdgB has recently been shown to encode a protein with Ca(2+)-binding sites and sequence similarity to rat brain phosphatidylinositol transfer protein; it is located near the rhabdomeric membranes in photoreceptor cells, where it has been suggested to play a role in membrane transport. The delay in recovery kinetics that we observe in olfactory tissue may reflect a defect in membrane restoration at the conclusion of the olfactory transduction cascade. The use of common molecules in the physiology of two olfactory organs, and in both visual and olfactory physiology, is discussed.

Animals↗
PubMed1994

Evidence that the Drosophila olfactory mutant smellblind defines a novel class of sodium channel mutation.

The smellblind (sbl) gene of Drosophila is associated with olfactory defects, and the paralytic (para) gene encodes a voltage-gated sodium channel. sbl and para have similar genetic map positions, many combinations of sbl and para mutations fail to complement, and two sbl mutations contain molecular lesions within the para transcription unit. sbl mutations also behave like para mutations in that they are enhanced by the mutation no action potential temperature-sensitive (mlenapts1). The simplest interpretation of these results is that sbl and para are the same gene. Two sbl mutations produce olfactory defects not characteristic of classic sodium channel mutations and do not show typical heat-sensitive paralysis, suggesting that these sbl mutants define a novel class of sodium channel mutation.

Alleles↗
PubMed1994

In vitro activity of readily available household materials against HIV-1: is bleach enough?

This report describes experiments assessing the effectiveness against HIV of potential disinfecting agents that are commonly available to IDU when they are sharing syringes. We exposed cell-free HIV, HIV-infected cells, and HIV-infected blood containing known quantities of HIV to household cleaning agents, alcohols, peroxide, and highly acidic materials for 1 min, in order to examine the effects of these materials on the infectivity of the HIV. Undiluted liquid laundry bleach and dilute liquid dish detergent reduced the number of culturable HIV to an undetectable level under the experimental conditions used. Diluted bleach was not completely effective. Other potential disinfecting agents, including ethanol, isopropyl alcohol, and hydrogen peroxide, were unable to disinfect high numbers of HIV-infected cells or infected blood. Liquid dish detergent warrants further study as a possible acceptable alternative to bleach. Our data provide support for recommendations to IDU that they disinfect shared syringes every time between users with full-strength liquid laundry bleach to reduce their risk of acquiring or transmitting HIV. When bleach is not available, liquid dish detergent or other available disinfecting agents such as rubbing alcohol, hydrogen peroxide, or high alcohol content beverages are more effective than water at disinfecting HIV, recognizing that these materials are less effective than bleach. Although these materials are effective, they should not be viewed as a substitute for decreased sharing of injection equipment by IDU, or increased availability of sterile needles and syringes.

1-Propanol↗
PubMed1993

Heteroduplex formation: a potential source of genotyping error from PCR products.

The formation of heteroduplexes from polymerase chain reaction (PCR) products has recently become a diagnostic tool that is routinely used for the prenatal detection of small deletions or insertions in a number of disease-causing alleles. We present evidence illustrating that heterozygous PCR products can manifest 'invisible' heteroduplexes that can ultimately lead to genotyping errors. Justifications for these 'invisible' heteroduplexes and requisite parameters to optimize their detection are presented.

Amniocentesis↗
PubMed1993

Anti-cellular antibodies in sera from vaccinated macaques can induce complement-mediated virolysis of human immunodeficiency virus and simian immunodeficiency virus.

Previous studies show that immunization of macaques with preparations of either human immunodeficiency virus (HIV) or simian immunodeficiency virus (SIV) that has been produced in human cells can induce antibodies against both viral antigens and human cellular antigens. This is due to the fact that certain host cell antigens are carried along with the virus during the purification process. The current series of experiments were performed to determine whether these anti-cellular antibodies can activate complement and whether the resultant complement activation could lead to virolysis of either HIV or SIV. Sera from macaques immunized with SIV or HIV (produced in the H9 human cell line) contained anti-cellular antibodies as determined by flow cytometry. Antibodies in these sera were capable of activating complement on uninfected human cells. Sera from the HIV-immunized macaques induced complement-mediated virolysis of both HIV and SIV. Similarly, sera from SIV-immunized macaques induced complement-mediated virolysis of both SIV and HIV. These results suggested that anti-cellular antibody in the sera could induce complement-mediated virolysis of either virus. To investigate this further, sera was absorbed with uninfected cells, which removed all of the virolytic activity for the heterologous virus. These in vitro studies indicate that complement activation can be initiated by anti-human cell antibodies, and that this activation can result in the destruction either HIV or SIV. This unusual antiviral mechanism may account for some portion of the resistance of human cell-immunized macaques to human cell-produced SIV that has been recently reported.

AIDS Vaccines↗