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1.
Trauma Violence Abuse ; 24(5): 3732-3747, 2023 12.
Article in English | MEDLINE | ID: mdl-36514242

ABSTRACT

This review aimed to identify U.S.-based, construct-validated measures of bystander intervention. Following PRISMA-P guidelines, electronic databases were searched, and emails were solicited identifying 8,559 articles for title screening. Abstracts and full texts were double screened, resulting in 24 scales meeting inclusion criteria: (a) measured a bystander-related construct in a situation where there was a potential for actual or perceived imminent physical or emotional harm, (b) written in English, and (c) statistically validated on U.S. samples. Most scales addressed the domain of interpersonal violence (67%), with fewer relating to bias/bullying (8.2%), mental health crises (12.5%), and substance use (12.5%). Most scales (71%) assessed the "take action" step of the situational model. The modal construct represented was intent/willingness/likelihood to intervene (50%). The average number of items on a scale was 14, and most (79%) provided Likert-style response options. None of the validated scales assessing behavior first accounted for an opportunity. Sample sizes ranged from 163 to 3,397, with the modal setting from colleges. Overall, samples were young (21.8 years old), White (75%), women (64%), and heterosexual (89%). Results indicate the need to validate additional measures that capture the "interpreting the situation as problematic" step of the situational model. Scales also need to be validated using diverse samples, particularly within the mental health crisis domain. Across all domains, validated measures need to be developed that first account for an opportunity when measuring actual bystander behavior. The information gleaned can be used to assist researchers in selecting measures and guide future measure development.


Subject(s)
Intention , Students , Adult , Female , Humans , Young Adult , Students/psychology , Universities
2.
Infect Prev Pract ; 2(2): 100047, 2020 Jun.
Article in English | MEDLINE | ID: mdl-34368697

ABSTRACT

BACKGROUND: Invasive candidiasis (IC) is the most common invasive fungal disease in patients admitted to critical care and is associated with high mortality rates. Diagnosis can be delayed by the poor sensitivity of culture-based methods, leading to unnecessary use of empirical antifungal therapy (EAFT). The fungal biomarker (1-3)-ß-d-glucan (BDG) has been shown to aid in the diagnosis of IC in critical care and has been incorporated into antifungal stewardship (AFS) programmes. AIM: To describe our experience using a diagnostics-driven AFS programme incorporating the fungal biomarker BDG, analyse its impact on antifungal therapy (AFT), and gain an improved understanding of the epidemiology of IC in our critical care unit (CrCU). METHODS: An AFS care pathway incorporating BDG was introduced in the CrCU in St James's Hospital, Dublin. Following an educational programme, compliance with the pathway was prospectively audited between December 1st, 2017 and July 31st, 2018. RESULTS AND CONCLUSION: One hundred and nine AFT episodes were included, of which 95 (87%) had a BDG sent. Of those with BDG results available at the time of decision-making, 38 (63%) were managed in accordance with the care pathway. In compliant episodes without IC, median EAFT duration was 5.5 days [IQR 4-7] and no increase in mortality or subsequent IC was observed. Although adopting a diagnostics-driven approach was found to be useful in the cohort of patients with BDG results available, the use of once-weekly BDG testing did not result in an observed reduction in the consumption of anidulafungin, highlighting an important limitation of this approach.

3.
Philos Trans A Math Phys Eng Sci ; 377(2149): 20180219, 2019 Jul 15.
Article in English | MEDLINE | ID: mdl-31130093

ABSTRACT

We use a combination of variable-temperature high-resolution synchrotron X-ray powder diffraction measurements and Monte Carlo simulations to characterize the evolution of two different types of ferroic multipolar order in a series of cyanoelpasolite molecular perovskites. We show that ferroquadrupolar order in [C3N2H5]2Rb[Co(CN)6] is a first-order process that is well described by a four-state Potts model on the simple cubic lattice. Likewise, ferrooctupolar order in [NMe4]2B[Co(CN)6] (B = K, Rb, Cs) also emerges via a first-order transition that now corresponds to a six-state Potts model. Hence, for these particular cases, the dominant symmetry breaking mechanisms are well understood in terms of simple statistical mechanical models. By varying composition, we find that the effective coupling between multipolar degrees of freedom-and hence the temperature at which ferromultipolar order emerges-can be tuned in a chemically sensible manner. This article is part of the theme issue 'Mineralomimesis: natural and synthetic frameworks in science and technology'.

4.
Adv Genet ; 94: 307-64, 2016.
Article in English | MEDLINE | ID: mdl-27131329

ABSTRACT

Although many insects successfully live in dangerous environments exposed to diverse communities of microbes, they are often exploited and killed by specialist pathogens. Studies of host-pathogen interactions (HPI) provide valuable insights into the dynamics of the highly aggressive coevolutionary arms race between entomopathogenic fungi (EPF) and their arthropod hosts. The host defenses are designed to exclude the pathogen or mitigate the damage inflicted while the pathogen responds with immune evasion and utilization of host resources. EPF neutralize their immediate surroundings on the insect integument and benefit from the physiochemical properties of the cuticle and its compounds that exclude competing microbes. EPF also exhibit adaptations aimed at minimizing trauma that can be deleterious to both host and pathogen (eg, melanization of hemolymph), form narrow penetration pegs that alleviate host dehydration and produce blastospores that lack immunogenic sugars/enzymes but facilitate rapid assimilation of hemolymph nutrients. In response, insects deploy an extensive armory of hemocytes and macromolecules, such as lectins and phenoloxidase, that repel, immobilize, and kill EPF. New evidence suggests that immune bioactives work synergistically (eg, lysozyme with antimicrobial peptides) to combat infections. Some proteins, including transferrin and apolipophorin III, also demonstrate multifunctional properties, participating in metabolism, homeostasis, and pathogen recognition. This review discusses the molecular intricacies of these HPI, highlighting the interplay between immunity, stress management, and metabolism. Increased knowledge in this area could enhance the efficacy of EPF, ensuring their future in integrated pest management programs.


Subject(s)
Ants/microbiology , Fungi/pathogenicity , Host-Pathogen Interactions , Animals , Beauveria/pathogenicity , Ecosystem , Metarhizium/pathogenicity
5.
J Med Entomol ; 46(3): 482-9, 2009 May.
Article in English | MEDLINE | ID: mdl-19496417

ABSTRACT

Single-strand conformation polymorphism (SSCP) analysis was examined in a 303-bp region of the 16S and 12S mitochondrial rDNA genes to study haplotype frequencies among populations of Gulf Coast ticks collected from Refugio Co., TX, Payne Co., OK, and two sites in Osage Co., KS. Seven haplotypes were identified from the 16S rDNA gene fragment, whereas only two haplotypes were detected from the 12S fragment. Only the results from the 16S rDNA fragment are discussed. Haplotype diversity was greatest in Kansas (site 1), where three of the four haplotypes detected were unique to this site. All Gulf Coast tick populations shared the fourth haplotype. Two haplotypes were determined for Texas and Oklahoma populations, one of which appeared only in Texas, whereas the other was shared. Nei's haplotype diversity (h) indicated that the Texas population was relatively homogeneous (15%), whereas the remaining populations were heterogeneous (42-59%), although the Bonferroni confidence interval found no significant differences (P < 0.05). Nucleotide sequencing of the seven haplotypes and subsequent phylogenetic analysis using neighbor joining showed a monophyletic relationship among these haplotypes. One haplotype, shared by both Oklahoma and Kansas (site 2), was basal to the remaining haplotypes and formed a distinct clade. Two haplotypes, both from Kansas (site 1), formed a unique clade, whereas the remaining four haplotypes were unresolved polytomies.


Subject(s)
DNA, Ribosomal/chemistry , Genes, Mitochondrial , Ixodidae/genetics , Polymorphism, Genetic , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal/genetics , Animals , Haplotypes , Kansas , Oklahoma , Phylogeny , Sequence Analysis, DNA , Texas
6.
Eur Respir J ; 33(1): 107-12, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18715876

ABSTRACT

Infants with recurrent wheeze have repeated episodes of airways obstruction; however, relatively little is known about the structure and function of their lungs when not symptomatic. The current authors evaluated whether infants with recurrent wheeze have smaller airway lumens or thickened airway walls, as well as decreased airway function. High-resolution computed tomography images 1 mm thick were obtained at three anatomic locations at an elevated lung volume and at functional residual capacity. Forced expiratory flows were also measured in subjects with recurrent wheeze. Airway lumen, wall areas and lung tissue density were not significantly different for recurrent wheeze (n = 17) and control (n = 14) subjects; however, subjects with recurrent wheeze had lower forced expiratory flows than predicted. Similar findings were obtained when subjects were grouped by exposure to tobacco smoke. These findings indicate that infants with recurrent wheeze, as well as exposure to tobacco smoke, have lower airway function when not symptomatic. The lower forced expiratory flows may result from a degree of airway narrowing that could not be resolved with the methodology employed or from other mechanisms, such as more collapsible airways or decreased pulmonary elastic recoil.


Subject(s)
Lung/pathology , Lung/physiopathology , Respiratory Sounds/diagnosis , Respiratory Sounds/physiopathology , Body Mass Index , Case-Control Studies , Child, Preschool , Female , Humans , Infant , Lung/diagnostic imaging , Male , Recurrence , Respiratory Function Tests , Respiratory Sounds/etiology , Tobacco Smoke Pollution , Tomography, X-Ray Computed
7.
FASEB J ; 20(11): 1880-2, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16877528

ABSTRACT

Genetic transformation systems based on Mos1 and piggyBac transposable elements are used to achieve stable chromosomal integration. However, integration sites are randomly distributed in the genome and transgene expression can be influenced by position effects. We developed a novel technology that utilizes chimeric transposases to direct integration into specific sites on a target DNA molecule. The Gal4 DNA binding domain was fused to the NH(2) terminus of the Mos1 and piggyBac transposases and a target plasmid was created that contained upstream activating sequences (UAS), to which the Gal4 DBD binds with high affinity. The transpositional activity of the Gal4-Mos1 transposase was 12.7-fold higher compared to controls where the Gal4-UAS interaction was absent and 96% of the recovered transposition products were identical, with integration occurring at the same TA site. In a parallel experiment, a Gal4-piggyBac transposase resulted in an 11.6-fold increase in transpositional activity compared to controls, with 67% of the integrations occurring at a single TTAA site. This technology has the potential to minimize nonspecific integration events that may result in insertional mutagenesis and reduced fitness. Site-directed integration will be advantageous to the manipulation of genomes, study of gene function, and for the development of gene therapy techniques.


Subject(s)
Aedes/genetics , DNA-Binding Proteins/genetics , Insect Proteins/genetics , Transposases/genetics , Aedes/enzymology , Animals , Base Sequence , DNA Primers , DNA Transposable Elements/genetics , DNA-Binding Proteins/metabolism , Insect Proteins/metabolism , Molecular Sequence Data , Mutant Chimeric Proteins/metabolism , Plasmids , Transposases/metabolism
9.
Article in English | MEDLINE | ID: mdl-15275658

ABSTRACT

Melittobia digitata is an ectoparasitoid of solitary bees and wasps that displays a trade-off between reproduction and dispersion through the development of two wing morphs (long and short wing morphs (LWM and SWM)). The morph differentiation of this species is an exceptional adaptation to maximize host exploitation and habitat colonization, and an understanding of the mechanisms underlying this developmental process will shed light on how nutrients or environmental elicitors alter regulatory pathways leading to physiological and metabolic changes resulting in such drastic developmental rearrangements. Here we describe the differential gene expression between SWM and LWM larvae of M. digitata in order to unravel the molecular mechanisms controlling the morph differentiation in this minute parasitoid and pinpoint the pathways involved in the regulation of this developmental process. The suppression subtractive hybridization (SSH) methodology was used to isolate differentially expressed genes using mRNA populations collected soon after morph development commitment. Dot blot analysis of 384 clones from a forward SSH library identified approximately 200 differentially expressed clones, including those transcripts present in very low abundance. Further DNA sequence analysis of a sub-population of 42 clones revealed 31 putatively unique transcripts, from which 5 were further analyzed by Northern blot analysis and semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR). The complete cDNA of one of these transcripts, a putative metalloprotease, was fully sequenced and is described. The role of the putative differentially expressed genes during the wing morph differentiation of M. digitata is discussed.


Subject(s)
Gene Expression Regulation, Developmental/physiology , Hymenoptera/physiology , Metalloproteases/genetics , Wings, Animal/growth & development , Wings, Animal/physiology , Amino Acid Sequence , Animals , Base Sequence , Defensins/genetics , Gene Expression Profiling , Gene Expression Regulation, Developmental/genetics , Gene Library , Hymenoptera/enzymology , Hymenoptera/genetics , Molecular Sequence Data , Phylogeny , Species Specificity , Trypsin/genetics , Wings, Animal/anatomy & histology
10.
Mol Genet Genomics ; 272(1): 67-75, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15221453

ABSTRACT

The left (5') inverted terminal repeat (ITR) of the Mos1 mariner transposable element was altered by site-directed mutagenesis so that it exactly matched the nucleotide sequence of the right (3') ITR. The effects on the transposition frequency resulting from the use of two 3' ITRs, as well as those caused by the deletion of internal portions of the Mos1 element, were evaluated using plasmid-based transposition assays in Escherichia coli and Aedes aegypti. Donor constructs that utilized two 3' ITRs transposed with greater frequency in E. coli than did donor constructs with the wild-type ITR configuration. The lack of all but 10 bp of the internal sequence of Mos1 did not significantly affect the transposition frequency of a wild-type ITR donor. However, the lack of these internal sequences in a donor construct that utilized two 3' ITRs resulted in a further increase in transposition frequency. Conversely, the use of a donor construct with two 3' ITRs did not result in a significant increase in transposition in Ae. aegypti. Furthermore, deletion of a large portion of the internal Mos1 sequence resulted in the loss of transposition activity in the mosquito. The results of this study indicate the possible presence of a negative regulator of transposition located within the internal sequence, and suggest that the putative negative regulatory element may act to inhibit binding of the transposase to the left ITR. The results also indicate that host factors which are absent in E. coli, influence Mos1 transposition in Ae. aegypti.


Subject(s)
Aedes/genetics , DNA Transposable Elements , DNA-Binding Proteins/genetics , Animals , Base Sequence , Escherichia coli/genetics , Genetic Vectors , Molecular Sequence Data , Plasmids , Transposases
11.
Br J Surg ; 90(3): 313-9, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12594666

ABSTRACT

BACKGROUND: Immune cells and cytokines are central to the systemic inflammatory response syndrome and multiple organ failure associated with acute pancreatitis. The specific role of T cells in this response is unclear, and this study focused on evaluating T cell activation and its regulation in patients with acute pancreatitis. METHODS: Peripheral blood samples of 14 patients with acute pancreatitis were obtained within 24 h of the onset of pain, within 48 h and at 1 week. T cell expression of surface markers CD69, CD62L and CD25 was measured. The production of interleukin (IL) 10 and IL-2 in vitro in response to the superantigen Staphylococcus enterotoxin B (SEB) was assessed. Serum samples from these patients were co-cultured with peripheral blood mononuclear cells from volunteers in the presence or absence of cytotoxic T lymphocyte-associated antigen (CTLA) 4 immunoglobulin, a specific inhibitor of antigen-dependent T cell activation. RESULTS: Expression of CD69 was significantly increased in CD3(+) and CD4(+) populations at 48 h and 1 week, and on CD8(+) cells at 1 week. There was a significant increase in the production of SEB-induced IL-2 compared with findings in controls, but no significant IL-10 response. Serum from patients with pancreatitis activated normal T cells. This response was abolished completely by CTLA-4. CONCLUSION: Acute pancreatitis results in the systemic activation of T cells. These cells are primed for a proinflammatory response to antigen stimulation and can be inhibited by antigen-specific T cell blockade. These data indicate that the immunoinflammatory response in acute pancreatitis is fueled by one or more serum antigens and offer prospects for further understanding of the aetiogenesis of pancreatitis.


Subject(s)
CD3 Complex/metabolism , CD4 Antigens/metabolism , Pancreatitis/immunology , T-Lymphocytes/immunology , Acute Disease , Adult , Enzyme-Linked Immunosorbent Assay , Female , Humans , Lymphocyte Activation/immunology , Lymphokines/metabolism , Male , Middle Aged , Prospective Studies , Systemic Inflammatory Response Syndrome/etiology , Systemic Inflammatory Response Syndrome/immunology
12.
Eur J Vasc Endovasc Surg ; 23(4): 303-8, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11991690

ABSTRACT

OBJECTIVES: endovascular repair of abdominal aortic aneurysms (E-AAA) has in recent years developed as an alternative to the conventional open repair (C-AAA). Adverse outcomes following the open approach may relate to immune cell activation and the systemic inflammatory response syndrome (SIRS) and organ failure but the benefits in this respect of the endovascular approach are unclear. This study evaluated this question and focused on T-cell activation and function. DESIGN: prospective clinical study. MATERIALS: twenty patients undergoing abdominal aortic aneurysm repair (12 C-AAA and 8 E-AAA). METHODS: peripheral T-cell expression of surface markers CD69, CD62L and CD25 in vivo and Interleukin 2 (IL-2) and Interleukin-10 (IL-10) responses to the superantigen staphylococcal enterotoxin B (SEB) in vitro were measured preoperatively, 24 h and 1 week postoperatively. RESULTS: there was no significant increase (p=0.23) in the incidence of SIRS in the open compared with the endovascular group. Enhanced T cell activation occurred following C-AAA and this was associated with significantly greater IL-2 production in response to SEB, with no change in IL-10 production. CONCLUSIONS: E-AAA attenuates proinflammatory T-cell changes compared with C-AAA repair. A reduction in T-cell activation and impaired responsiveness to superantigen suggests that the immunological sequelae of the endovascular approach to aneurysm repair is more favourable than after the open approach with potentially less risk of adverse outcomes. Proof of this thesis will require a larger prospective study.


Subject(s)
Aortic Aneurysm, Abdominal/surgery , Cytokines/immunology , Cytokines/metabolism , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Aged , Antigens, CD/metabolism , Antigens, Differentiation, T-Lymphocyte/metabolism , Female , Humans , Interleukin-2/metabolism , L-Selectin/metabolism , Lectins, C-Type , Male , Prospective Studies , Receptors, Interleukin-2/metabolism
13.
Am J Prev Med ; 21(2): 93-100, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11457628

ABSTRACT

BACKGROUND: While public health leaders recommend screening for partner violence, the predictive value of this practice is unknown. The purpose of this study was to test the ability of a brief three-question violence screen to predict violence against women in the ensuing months. METHODS: We conducted a prospective cohort study of adult women participating in the Colorado Behavioral Risk Factor Surveillance System (BRFSS), a population-based, random-digit-dialing telephone survey. During 8 monthly cohorts, 695 women participated in the BRFSS; 409 women participated in follow-up telephone interviews approximately 4 months later. Violent events during the follow-up period, measured using a modified 28-item Conflict Tactics Scale, were compared between women who initially screened positive and those who screened negative. RESULTS: Among BRFSS respondents, 8.4% (95% confidence interval [CI]=6.3%-10.5%) had an initial positive screen. During the follow-up period, women who screened positive were 46.5 times (5.4-405) more likely to experience severe physical violence, 11.7 times (5.0- 27.3) more likely to experience physical violence, 3.6 (2.4-5.2) times more likely to experience verbal aggression, and 2.5 times (1.2-5.1) more likely to experience sexual coercion. In a multivariate model, separation from one's spouse and a positive screen were significant independent predictors of physical violence. CONCLUSIONS: A brief violence screen identifies a subset of women at high risk for verbal, physical, and sexual partner abuse over the following 4 months. Women with a positive screen who are separated from their spouse are at highest risk.


Subject(s)
Mass Screening , Spouse Abuse/diagnosis , Adolescent , Aged , Aged, 80 and over , Cohort Studies , Confidence Intervals , Female , Health Surveys , Humans , Interviews as Topic , Multivariate Analysis , Predictive Value of Tests , Prospective Studies , Reproducibility of Results , Spouse Abuse/statistics & numerical data
14.
Insect Biochem Mol Biol ; 30(11): 1003-8, 2000 Nov.
Article in English | MEDLINE | ID: mdl-10989286

ABSTRACT

Derivatives of the mariner transposable element, Mos1, from Drosophila mauritiana, can integrate into the germ-line of the yellow fever mosquito, Aedes aegypti. Previously, the transposase required to mobilize Mos1 was provided in trans by a helper plasmid expressing the enzyme under the control of the D. psuedoobscura heat-shock protein 82 promoter. Here we tested whether purified recombinant Mos1 transposase could increase the recovery of Ae. aegypti transformants. Mos1 transposase was injected into white-eyed, kh(w)/kh(w), Ae. aegypti embryos with a Mos1 donor plasmid containing a copy of the wild-type allele of the D. melanogaster cinnabar gene. Transformed mosquitoes were recognized by partial restoration of eye color in the G(1) animals and confirmed by Southern analyses of genomic DNA. At Mos1 transposase concentrations approaching 100 nM, the rate of germ-line transformants arising from independent insertions in G(0) animals was elevated 2-fold compared to that seen in experiments with helper plasmids. Furthermore, the recovery of total G(1) transformants was increased 7.5-fold over the frequency seen with co-injected helper plasmid. Southern blot analyses and gene amplification experiments confirmed the integration of the transposons into the mosquito genome, although not all integrations were of the expected cut-and-paste type transposition. The increased frequency of germ-line integrations obtained with purified transposase will facilitate the generation of Mos1 transgenic mosquitoes and the application of transgenic approaches to the biology of this important vector of multiple pathogens.


Subject(s)
Aedes/physiology , DNA Transposable Elements/genetics , Drosophila/genetics , Transposases/metabolism , Aedes/enzymology , Alleles , Animals , Animals, Genetically Modified , Blotting, Southern , DNA , Drosophila/enzymology , Gene Amplification , Germ Cells
16.
Insect Mol Biol ; 9(1): 11-8, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10672066

ABSTRACT

The Hermes transposable element is derived from the house fly, Musca domestica, and can incorporate into the germline of the yellow fever mosquito, Aedes aegypti. Preliminary Southern analyses indicated that Hermes integrated along with the marker gene into the mosquito genomic DNA. Here we show that Hermes integrations are accompanied by the integration of the donor plasmid as well. In addition, breaks in the donor plasmid DNAs do not occur precisely, or at the end of the terminal inverted repeats, and are accompanied by small deletions in the plasmids. Furthermore, integrations do not cause the typical 8-bp duplications of the target site DNA. No integrations are observed in the absence of a source of Hermes transposase. The Hermes transposase clearly did not catalyse precise cut-and-paste transposition in these transformed lines. It may have integrated the transposon through general recombination or through a partial replicative transposition mechanism. The imprecision of Hermes integration may result from interactions of the transposase with an endogenous hAT-like element in the mosquito genome.


Subject(s)
Aedes/genetics , DNA Transposable Elements , Germ-Line Mutation , Animals , Base Sequence , Gene Amplification , Genetic Markers , Molecular Sequence Data , Plasmids , Repetitive Sequences, Nucleic Acid , Transposases/metabolism
17.
J Interv Card Electrophysiol ; 4(4): 591-3, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11141204

ABSTRACT

Extraction of chronically implanted pacing and defibrillator leads is facilitated by using specialized locking stylets placed in the lead to allow application of traction and to stabilize the lead during sheath dissection of fibrotic tissue. We report the initial multicenter series of cases using a novel lead locking device (LLD). In 57 consecutive patients presenting at 6 institutions for lead extraction, 99 leads were treated using the LLD. After removing the pulse generator, leads were severed, the inner coil dilated and an LLD was successfully inserted and locked in the inner lumen of 95/99 (96 %) leads. With traction applied to the LLD, a variety of sheaths were advanced over the lead body to separate it from adhesions. In 97/99 (98 %) leads, all or most of the lead was removed via the implant vein; 2 leads were removed via the femoral vein. No major complications were observed. The LLD deploys safely and reliably, and provides stable support for advancement of dissecting sheaths.


Subject(s)
Defibrillators, Implantable/adverse effects , Device Removal/instrumentation , Equipment Failure , Adult , Aged , Aged, 80 and over , Arrhythmias, Cardiac/therapy , Chi-Square Distribution , Device Removal/methods , Electric Countershock/instrumentation , Equipment Safety , Female , Humans , Male , Middle Aged , Sensitivity and Specificity
18.
Proc Natl Acad Sci U S A ; 96(23): 13399-403, 1999 Nov 09.
Article in English | MEDLINE | ID: mdl-10557332

ABSTRACT

A rapid and reproducible method of inhibiting the expression of specific genes in mosquitoes should further our understanding of gene function and may lead to the identification of mosquito genes that determine vector competence or are involved in pathogen transmission. We hypothesized that the virus expression system based on the mosquito-borne Alphavirus, Sindbis (Togaviridae), may efficiently transcribe effector RNAs that inhibit expression of a targeted mosquito gene. To test this hypothesis, germ-line-transformed Aedes aegypti that express luciferase (LUC) from the mosquito Apyrase promoter were intrathoracically inoculated with a double subgenomic Sindbis (dsSIN) virus TE/3'2J/anti-luc (Anti-luc) that transcribes RNA complementary to the 5' end of the LUC mRNA. LUC activity was monitored in mosquitoes infected with either Anti-luc or control dsSIN viruses expressing unrelated antisense RNAs. Mosquitoes infected with Anti-luc virus exhibited 90% reduction in LUC compared with uninfected and control dsSIN-infected mosquitoes at 5 and 9 days postinoculation. We demonstrate that a gene expressed from the mosquito genome can be inhibited by using an antisense strategy. The dsSIN antisense RNA expression system is an important tool for studying gene function in vivo.


Subject(s)
Aedes/enzymology , Luciferases/genetics , RNA, Antisense/genetics , Sindbis Virus/genetics , Animals , Animals, Genetically Modified , Apyrase/metabolism , Blotting, Western , Reproducibility of Results , Salivary Glands/enzymology , Salivary Glands/virology
19.
Gene ; 226(2): 317-25, 1999 Jan 21.
Article in English | MEDLINE | ID: mdl-9931506

ABSTRACT

Molecular genetic analyses of biological properties characteristic of insect vectors of disease, such as hematophagy and competence for pathogens, require the ability to isolate and characterize genes involved in these processes. We have been working to develop molecular approaches for studying the promoter function of genes that are expressed specifically in the adult salivary glands of the yellow fever mosquito, Aedes aegypti. Genomic DNA fragments containing cis-acting promoter elements from the Maltase-like I (MalI) and Apyrase (Apy) genes were cloned so as to direct the expression of the reporter gene, luciferase (luc). The function of the promoters was assayed transiently in cultured insect cells and by germ-line transformation of Ae. aegypti. MalI and Apy DNA fragments consisting of at least 650 nucleotides (nt) of DNA immediately adjacent to the 5'-end of the initiation codon of the mosquito genes directed constitutive expression of the luc reporter gene in cultured cells. When introduced into Ae. aegypti chromosomes, approximately 1.5 kilobases (kb) of each promoter were able to direct the predicted developmental-, sex- and tissue-specific expression of the reporter gene in patterns identical to those determined for the respective endogenous genes.


Subject(s)
Aedes/genetics , Luciferases/genetics , Promoter Regions, Genetic , Salivary Glands/enzymology , Aedes/cytology , Aedes/enzymology , Animals , Base Sequence , Blotting, Northern , Cell Line , Coleoptera/enzymology , DNA Primers , Female , Genes, Reporter , RNA, Messenger/genetics , Recombinant Proteins/genetics , Transformation, Genetic
20.
Parassitologia ; 41(1-3): 461-71, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10697903

ABSTRACT

We are developing transgenic mosquitoes resistant to malaria parasites to test the hypothesis that genetically-engineered mosquitoes can be used to block the transmission of the parasites. We are developing and testing many of the necessary methodologies with the avian malaria parasite, Plasmodium gallinaceum, and its laboratory vector, Aedes aegypti, in anticipation of engaging the technical challenges presented by the malaria parasite, P. falciparum, and its major African vector, Anopheles gambiae. Transformation technology will be used to insert into the mosquito a synthetic gene for resistance to P. gallinaceum. The resistance gene will consist of a promoter of a mosquito gene controlling the expression of an effector protein that interferes with parasite development and/or infectivity. Mosquito genes whose promoter sequences are capable of sex- and tissue-specific expression of exogenous coding sequences have been identified, and stable transformation of the mosquito has been developed. We now are developing the expressed effector portion of the synthetic gene that will interfere with the transmission of the parasites. Mouse monoclonal antibodies that recognize the circumsporozoite protein of P. gallinaceum block sporozoite invasion of mosquito salivary glands, as well as abrogate the infectivity of sporozoites to a vertebrate host, the chicken, Gallus gallus, and block sporozoite invasion and development in susceptible cell lines in vitro. Using the genes encoding these antibodies, we propose to clone and express single-chain antibody constructs (scFv) that will serve as the effector portion of the gene that interferes with transmission of P. gallinaceum sporozoites.


Subject(s)
Aedes/genetics , Genetic Engineering , Malaria, Falciparum/transmission , Plasmodium falciparum/genetics , Plasmodium gallinaceum/genetics , Animals , Antibodies, Monoclonal , Chickens , Immunity, Innate/genetics , Malaria, Falciparum/immunology , Malaria, Falciparum/parasitology , Mice , Transgenes
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