Background: From 2010 to 2013, the Department of Veterans Affairs (VA) funded a large pilot initiative to implement noninstitutional long-term services and supports (LTSS) programs to support aging Veterans. Our team evaluated implementation of 59 VA noninstitutional LTSS programs.
Purpose: The specific objectives of this study are to (a) examine the challenges influencing program implementation comparing active sites that remained open and inactive sites that closed during the funding period and (b) identify ways that active sites overcame the challenges they experienced.
An increasing number of travellers cross international borders and is exposed to arthropod-borne diseases. Primary care physician should not only know and give advice on preventive measures, but also estimate the risk to an individual traveller. Personal protective measures are an important and sometimes the only way to prevent arthropod-borne diseases.
View Article and Find Full Text PDFSuccessful protection against haematophagous insects and ticks, especially in areas where transmission of diseases occurs, requires a consistent application of a combination of appropriate measures. However, this can never substitute a chemoprophylaxis. Which measures have to be used depends on the circumstances under which they have to work.
View Article and Find Full Text PDFBackground: The treatment of human wounds with fly larvae is an ancient procedure recently reintroduced into medical practice under the term of biosurgery. The crucial technical problem of biosurgery is asepsis of the larvae.
Patients And Methods: Since February 1999, we conducted a prospective observational study on the use of maggot debridement therapy in the management of ulcers refractory to standard treatment.
In susceptible mouse strains, infection of mice with Plasmodium berghei ANKA (PbA) results in a lethal complication, cerebral malaria. Cerebral malaria is due to the immune response induced by the parasite, which results in an increased production of TNF, known to increase the expression of adhesion molecules on the endothelia. To investigate the role of the adhesion molecule ICAM-1 (CD54), we infected wild-type (+/+) and ICAM-1-deficient (-/-) mice with PbA.
View Article and Find Full Text PDFParasitology
February 1999
Nitric oxide (NO) production has been suggested to play a role as effector molecule in the control of the malarial infections. However, the roles of this molecule are debated. To assess whether blood-stage parasite killing is NO dependent, we investigated the course of blood-stage Plasmodium chabaudi chabaudi (Pcc) infections in inducible nictric oxide synthase (iNOS)-deficient mice.
View Article and Find Full Text PDFParasitology
February 1999
Nitric oxide (NO) production has been suggested to be required for the development of cerebral malaria. However, the importance of this molecule for the appearance of this pathology is debated. To assess whether murine cerebral malaria is NO dependent, we investigated the course of blood-stage Plasmodium berghei ANKA (PbA) infections in inducible nitric oxide synthase (iNOS)-deficient mice.
View Article and Find Full Text PDFIt has been suggested that phospholipids and antibodies directed against phospholipids are important in the pathology of malaria. We have investigated the influence of immunizations with phospholipids on the course of subsequent blood-stage Plasmodium chabaudi chabaudi infections in ICR inbred mice. We observed a significant reduction in the parasitaemia following immunization with phosphatidylcholine (PC), but not with phosphatidylethanolamine (PE) immunization.
View Article and Find Full Text PDFThe ability of deproteinated malaria exoantigens from Plasmodium falciparum (Pf-MT) and P. berghei ANKA (PbA-MT) to activate murine haematopoietic cells was analysed in vitro. Malaria toxins (MT) of both plasmodium species induced cell proliferation and the production of IFN-gamma in overnight and long-term (5 days) spleen and bone marrow cultures and a reduction of the number of TNF-alpha spot forming cells (SFC).
View Article and Find Full Text PDFThe lack of correlation between parasitaemia and anaemia in severe malaria indicates that factors in addition to schizont rupture or erythrophagocytosis contribute to anaemia. We asked whether malaria toxin (MT) from Plasmodium berghei or P. chabaudi might impair erythropoiesis.
View Article and Find Full Text PDFInterferon-gamma receptor (IFN-gamma R) deficient mice parasitized with blood-stage Plasmodium chabaudi chabaudi were used to assess the anti-malarial activity of interferon-gamma (IFN-gamma). There was no significant difference in the parasitaemia between the two types of mice during the first peak of parasitaemia. However, IFN-gamma R deficient mice displayed an increased leucocytosis and a high mortality rate, whereas all of the wild type mice survived.
View Article and Find Full Text PDFJ Immunol Methods
May 1997
We have investigated the correlation between results obtained by three different methods (semi-quantitative RT-PCR, ELISA and ELISPOT) used to measure cytokine expression by mouse leukocytes. The production of the cytokines tumour necrosis factor-alpha (TNF alpha), interferon-gamma (IFN gamma) and interleukin-4 (IL-4), was analysed with all three methods. In a simple experimental murine in vivo model of leukocyte stimulation, consisting of a single intravenous injection of anti-CD3 antibodies followed by a short incubation in vitro, the results obtained with spleen cells for each of the three cytokines differed greatly, depending on the method used.
View Article and Find Full Text PDFInfection with Plasmodium berghei ANKA (PbA) causes fatal cerebral malaria (CM). While a pathogenic role for tumor necrosis factor (TNF) has been established, we asked whether a disruption of interferon-gamma (IFN-gamma) signaling would modulate CM. We demonstrate here that IFN-gammaR-deficient mice are completely protected from CM.
View Article and Find Full Text PDFTumor necrosis factor (TNF) induced by Plasmodium berghei ANKA (PbA) infection was suggested to play an important role in the development of cerebral malaria (CM). We asked whether TNF-alpha/beta double-deficient mice, which have a complete disruption of the TNF-signaling pathways, are protected from CM and what might be the possible mechanisms of protection. PbA infection induces fatal CM in wild-type mice, which die within 5 to 8 days with severe neurological signs.
View Article and Find Full Text PDFA cDNA fragment encoding the complete coding region of a 27-kDa protein (p27) of Dirofilaria immitis was cloned. Antibody to the recombinant p27 bound to hypodermal tissues of third (L3) and fourth stage larvae (L4) of D. immitis and to both the hypodermis and the cuticle of L3s of Onchocerca volvulus, as visualized by immunoelectronmicroscopy.
View Article and Find Full Text PDFAcanthocheilonema viteae is a parasitic nematode of rodents. We identified the chitinase of A. viteae infective stage larvae (L3) as the main target of the humoral immune response of jirds, which were protected against challenge infection after vaccination with irradiation attenuated L3.
View Article and Find Full Text PDFThe major surface protein MSP-1 of Plasmodium falciparum blood-stage malaria parasites contains notably conserved sequence blocks with unknown function. The recombinant protein 190L, which represents such a block, exhibits a high affinity for red blood cell membranes. We demonstrate that both 190L and native MSP-1 protein bind to the inner red blood cell membrane skeleton protein spectrin.
View Article and Find Full Text PDFToxocara canis infective larvae are known to produce abundant glycosylated molecules which may be found associated with the surface or secreted into their environment. Using a range of fluorescein-conjugated and gold-conjugated lectins, the localization of particular carbohydrates was defined on the surface of live parasites, and internally at the ultrastructural level. Surface exposure of N-acetyl galactosamine and N-acetyl glucosamine was deduced by binding of FITC-conjugated Helix pomatia (HPA) and wheat-germ agglutinins (WGA).
View Article and Find Full Text PDFAn electron-dense coat covering the surface of Toxocara canis infective-stage larvae is described. This coat readily binds to cationized ferritin and ruthenium red, indicating a net negative charge and mucopolysaccharide content, and can be visualized by immuno-electron microscopy only if cryosectioning is employed. Monoclonal antibodies reactive to the surface of live larvae bind the surface coat but not the underlying cuticle in ultrathin cryosections.
View Article and Find Full Text PDFThe presence and distribution of circumsporozoite protein (CSP) epitopes located in the repetitive and non-repetitive regions were studied in three Plasmodium falciparum strains, NF54, IFA5 and IFA6. It was found by immunofluorescence, Western blotting and immunoelectron microscopy that mAbs to epitopes of the repetitive domaine bound similarly to the CSP of all three strains. MAbs to epitopes of the flanking regions yielded either some strain differences (mAbs to the C-terminal end), or reacted only in immunofluorescence tests on whole sporozoites (mAbs to the N-terminal end).
View Article and Find Full Text PDFThe classical view of nematode parasites depicts their surface as the epicuticle, the outermost layer of a thick extracellular cuticle. However, many stages and species of nematode have been found to bear an electron-dense cuter envelope distinct from and distal to the epicuticle itself. In this review, Mark Blaxter and colleagues summarize some wide-ranging studies in both free-living and parasitic nematodes, and suggest that, in many cases, it is the surface coat rather than the cuticle that displays dynamic properties thought to be involved in immune evasion by parasites.
View Article and Find Full Text PDFSecretion and luminal formation of the peritrophic membrane (PM) were induced in female Anopheles stephensi and Aedes aegypti by feeding the mosquitoes on a warmed suspension of latex particles in Ringer's solution. The PM in A. stephensi was produced from apical secretion vesicles stored in the midgut epithelial cells and secreted into the lumen during feeding.
View Article and Find Full Text PDFMonoclonal antibodies to metacyclic surface coat glycoproteins of Trypanosoma brucei brucei STIB 247LG were produced for a study of the synthesis of metacyclic variable surface glycoproteins (VSGs) within the salivary gland of Glossina morsitans morsitans, and of the first exchange of the surface glycoproteins after infection in mice. Immunofluorescence antibody tests and protein A-gold labelling revealed that the VSGs are continuously integrated into the whole surface of the trypanosome while it is still attached to the gland epithelium. A pool of 8 antibodies recognized about 50% of the metacyclic forms present in the saliva of an infected tsetse fly, which confirmed the heterogeneity of the metacyclic VSG-generation.
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