Presence of American cutaneous leishmaniasis vectors surrounding the city of Medellín, Colombia

The presence of Lutzomyia (Helcocyrtomyia) hartmanni, as a vector of Leishmania colombiensis and L. columbiana (Verrucarum group), recently incriminated in the transmission of leishmaniasis, and L. pia (Verrucarum group) are reported for the first time in a periurban area of Medellín city. There is thus a risk of leishmaniasis transmission in this town.

High proportion of wrongly identified methicillin-resistant Staphylococcus aureus carriers by use of a rapid commercial PCR assay due to presence of staphylococcal cassette chromosome element lacking the mecA gene.

During a 9-month period, 217 patients were newly diagnosed as methicillin-resistant Staphylococcus aureus (MRSA) carriers by using a commercial rapid PCR-based test (GeneXpert). However, no MRSA was recovered by culturing the second swab in 61 of these patients. Further analyses showed that 28 (12.9%) of the patients harbored S. aureus isolates with a staphylococcal cassette chromosome element lacking the mecA gene and were thus incorrectly determined to be MRSA carriers.

First report on the presence of Biomphalaria straminea in the municipality of Jaboticatubas, State of Minas Gerais, Brazil

This is the first report on occurrence of Biomphalaria straminea in the district of São José de Almeida (municipality of Jaboticatubas) State of Minas Gerais, Brazil. The presence of B. glabrata and B. tenagophila had already been reported in this area. Such municipality is part of the metropolitan region of Belo Horizonte and comprises 60% of the Tourist Complex of Serra do Cipó. Since the 1950s throughout the 1990s, a schistosomiasis prevalence ranging from 15 to 40% has been observed. Although no B. straminea specimen has been found naturally infected in the region, descendants of these snails collected in the area, showed to be experimentally susceptible to Schistosoma mansoni infection reaching rates from 14.6 to 28.6%. Even not being found naturally infected, in the State of Minas Gerais, the possibility that the species B. straminea may keep endemicity foci of schistosomiasis should be regarded, as in the Northeastern region of Brazil where the high density of this planorbid and the social-economic and sanitary conditions enable to the transmission.

Presence of Wolbachia endosymbionts in microfilariae of Wuchereria bancrofti (Spirurida: Onchocercidae) from different geographical regions in India

In view of the recent discovery of rickettsial endosymbionts, Wolbachia in lymphatic filarial parasites, Wuchereria bancrofti and Brugia malayi and subsequently of their vital role in the survival and development of the latter, antibiotics such as tetracycline are being suggested for the treatment of lymphatic filariasis, by way of eliminating the endosymbiont. But, it is essential to assess their presence in parasites from areas endemic for lymphatic filariasis before such a new control tool is employed. In the present communication, we report the detection of Wolbachia endosymbionts in microfilariae of W. bancrofti parasites collected from geographically distant locations of India, such as Pondicherry (Union Territory), Calicut (Kerala), Jagadalpur (Madhya Pradesh), Thirukoilur (TamilNadu), Chinnanergunam (TamilNadu), Rajahmundry (Andhra Pradesh), and Varanasi (Uttar Pradesh), using Wolbachia specific 16S rDNA polymerase chain reaction.

The presence of Fasciola hepatica (Liver-fluke) in humans and cattle from a 4,500 Year old archaeological site in the Saale-Unstrut Valley, Germany

During an excavation of a site of the corded ware culture in the Saale-Unstrut-Valley (ca. 3000 BC) in Germany, a soil sample from the pelvis of a human skeleton was studied under palaeoparasitological aspects. Eggs of the trematode Fasciola hepatica and of the nematode genus Capillaria were found. This is the first case of a direct association of a F. hepatica-infestation to both a prehistoric human skeleton and domesticated animal remains. Sheep and cattle bones were present at the same site and F. hepatica eggs were found in bovine samples. This strongly points toward an existing infection cycle, involving humans as a final host.

Epidemiology of Chagas disease in Jaguaruana, Ceará, Brazil. I. Presence of triatomines and index of Trypanosoma cruzi infection in four localities of a rural area

In order to assay the triatomine infestation and domiciliation in the rural area of Jaguaruana district, state of Ceará, Brazil, we studied, from November 2000 to April 2002, 4 localities comprising 158 domiciles as a whole, with an average of 4 inhabitants/house, who are dwelling in there for more than 7 years. Most houses have tile-covered roofs and the walls built with plaster-covered bricks (57%), followed by bricks without plaster (33%), and mud walls (7.5%). A total of 3082 triatomines were captured from different locations, according to the following capture plan: (a) intradomiciles: 238 Triatoma brasiliensis, 6 T. pseudomaculata, 9 Rhodnius nasutus, and 2 Panstrongylus lutzi; (b) peridomiciles (annexes): 2069 T. brasiliensis, 223 T. pseudomaculata, 121 R. nasutus, and 1 P. lutzi; (c) wild, in carnauba palms (Copernicia prunifera): 413 R. nasutus. From the captured triatomines, 1773 (57.5%) were examined. The natural index of Trypanosoma cruzi infection ranged from 10.8% to 30.2% (average of 17%), depending on the species and the location from where the triatomines were captured.

Coronary sinus atresia with persistent left superior vena cava: unusual clinical presentation and endovascular management.

Atresia of the coronary sinus (ACS) is a rare congenital anomaly. When associated with persistent left superior vena cava (PLSVC), this defect could have no significant hemodynamic effect, and the patient might remain asymptomatic. However, vascular interventions might induce changes or complications that could show the anomaly. Appropriate management requires a good understanding of this condition. We present the first reported case of ACS and PLSVC occurring after thrombosis of the innominate vein (IV) after central venous catheter placement. The patient presented with atypical subacute chest pain and recurrent extrasystoles. Diagnosis and characterization of vascular anomalies was made by computed tomography phlebography, and the patient was successfully managed by endovascular recanalization of the IV.

Prediction of recanalization in acute stroke patients receiving intravenous and endovascular revascularization therapy.

BACKGROUND AND PURPOSE: The study aims to assess the recanalization rate in acute ischemic stroke patients who received no revascularization therapy, intravenous thrombolysis, and endovascular treatment, respectively, and to identify best clinical and imaging predictors of recanalization in each treatment group. METHODS: Clinical and imaging data were collected in 103 patients with acute ischemic stroke caused by anterior circulation arterial occlusion. We recorded demographics and vascular risk factors. We reviewed the noncontrast head computed tomographies to assess for hyperdense middle cerebral artery and its computed tomography density. We reviewed the computed tomography angiograms and the raw images to determine the site and degree of arterial occlusion, collateral score, clot burden score, and the density of the clot. Recanalization status was assessed on recanalization imaging using Thrombolysis in Myocardial Ischemia. Multivariate logistic regressions were utilized to determine the best predictors of outcome in each treatment group. RESULTS: Among the 103 study patients, 43 (42%) received intravenous thrombolysis, 34 (33%) received endovascular thrombolysis, and 26 (25%) did not receive any revascularization therapy. In the patients with intravenous thrombolysis or no revascularization therapy, recanalization of the vessel was more likely with intravenous thrombolysis (P = 0·046) and when M1/A1 was occluded (P = 0·001). In this subgroup of patients, clot burden score, cervical degree of stenosis (North American Symptomatic Carotid Endarterectomy Trial), and hyperlipidemia status added information to the aforementioned likelihood of recanalization at the patient level (P < 0·001). In patients with endovascular thrombolysis, recanalization of the vessel was more likely in the case of a higher computed tomography angiogram clot density (P = 0·012), and in this subgroup of patients gender added information to the likelihood of recanalization at the patient level (P = 0·044). CONCLUSION: The overall likelihood of recanalization was the highest in the endovascular group, and higher for intravenous thrombolysis compared with no revascularization therapy. However, our statistical models of recanalization for each individual patient indicate significant variability between treatment options, suggesting the need to include this prediction in the personalized treatment selection.

Quantitative genetic modeling and inference in the presence of nonignorable missing data.

Natural selection is typically exerted at some specific life stages. If natural selection takes place before a trait can be measured, using conventional models can cause wrong inference about population parameters. When the missing data process relates to the trait of interest, a valid inference requires explicit modeling of the missing process. We propose a joint modeling approach, a shared parameter model, to account for nonrandom missing data. It consists of an animal model for the phenotypic data and a logistic model for the missing process, linked by the additive genetic effects. A Bayesian approach is taken and inference is made using integrated nested Laplace approximations. From a simulation study we find that wrongly assuming that missing data are missing at random can result in severely biased estimates of additive genetic variance. Using real data from a wild population of Swiss barn owls Tyto alba, our model indicates that the missing individuals would display large black spots; and we conclude that genes affecting this trait are already under selection before it is expressed. Our model is a tool to correctly estimate the magnitude of both natural selection and additive genetic variance.

Evaluation of adherence, hemagglutination, and presence of genes codifying for virulence factors of Acinetobacter baumannii causing urinary tract infection

Acinetobacter baumannii is a strictly aerobic bacterium which causes severe infections, however its pathogenic characteristics are not well defined. Thirteen A. baumannii strains isolated from urine of hospitalized and nonhospitalized patients with different ages were investigated for the presence of virulence factors. The isolates belonged to biotypes 2, 6, and 9 and were sensitive to imipenem. The majority of them showed resistance to amikacin, ceftazidime, ceftriaxone, ciprofloxacin, gentamicin, norfloxacin, and trimethoprim-sulfamethoxazole. None of A. baumannii strains presented genes codifying for 17 different virulence factors previously described in uropathogenic Escherichia coli, when tested by polymerase chain reaction (PCR). Nine isolates agglutinated human group AB erythrocytes, in presence of mannose, but none of them agglutinated group O erythrocytes. Adherence to polystyrene was observed in 7 isolates, and this result did not correlate with that obtained in hemagglutination assay. All the isolates were able to grow in iron-limiting conditions, showing that A. baumannii produces some type of siderophore. However, the genes iutA and fyuA, from iron uptake system of E. coli and Yersinia sp., respectively, were not present in the isolates, suggesting the presence of a different type of siderophore. The fimbriae of A. baumannii strains that mediates the adherence are possibly mannose-resistant, eventhough the mechanism of adherence to human epithelial cells still remains to be elucidated.

Presence of JC virus-specific CTL in the cerebrospinal fluid of PML patients: rationale for immune-based therapeutic strategies.

OBJECTIVES: There is urgent need of a treatment for progressive multifocal leukoencephalopathy (PML), caused by the polyomavirus JC (JCV). To evaluate the rationale for immunotherapy of PML, we explored whether JCV-specific cytotoxic T lymphocytes (CTL) can penetrate the central nervous system (CNS). In addition, we studied the breadth of their T-cell receptor (TCR) repertoire, and sought to establish a reliable method to expand these cells in vitro. DESIGN AND METHODS: We enrolled 18 patients in this study, including 16 with proven or possible PML (15 HIV-positive and one HIV-negative), and two HIV-positive patients with other neurological diseases. Detection of JCV-specific CTL in the blood and the cerebrospinal fluid was performed by Cr release and tetramer staining assays in 15 patients. RESULTS: Of 11 PML patients with analyzable cerebrospinal fluid (CSF), two had no detectable JCV-specific CTL in the blood and CSF and died 3.7 and 7.2 months later. The nine remaining patients had an inactive course of PML and detectable JCV-specific CTL in the blood. In addition, four of them (44%) also had detectable JCV-specific CTL in the CSF. Both HIV-positive patients with OND had detectable JCV-specific CTL in the blood and one in the CSF. Using tetramer technology, we obtained highly enriched JCV-specific CTL lines that were able to kill target cells presenting JCV peptides. The breadth of the TCR repertoire was CTL epitope dependent. CONCLUSIONS: These results indicate that JCV-specific CTL are present in the CNS of PML patients and pave the way for an immune-based therapeutic approach.

Habitat preference of freshwater snails in relation to environmental factors and the presence of the competitor snail Melanoides tuberculatus (Müller, 1774)

Our objective is to evaluate the habitat preference of freshwater snails in relation to environmental factors and the presence of the competitor snail Melanoides tuberculatus. In the first phase, snails was collected at 12 sites. This sampling sites presented a degree of organic input. In the second phase 33 sampling sites were chosen, covering a variety of lotic and lentic environments. The snail species found at Guapimirim, state of Rio de Janeiro, displayed a marked habitat preference, specially in relation to the physical characteristics of each environment. Other limiting factors for snail distribution at the studied lotic environments were the water current velocity and the amount of organic matter, mainly to Physa marmorata, M. tuberculatus, and Biomphalaria tenagophila. The absence of interactions between M. tuberculatus and another snails could be associated to the distinct spatial distribution of those species and the instability of habitats. This later factor may favor the coexistence of M. tuberculatus with B. glabrata by reduction of population density. In areas of schistosomiasis transmission some habitat modification may add to the instability of the environment, which would make room for the coexistence of M. tuberculatus and Biomphalaria spp. In this way, some of the usual measures for the control of snail hosts would prevent the extinction of populations of Biomphalaria spp. by M. tuberculatus in particular habitats.

On the presence of hepatic stellate cells in portal spaces

Previous studies in mice with hypervitaminosis A have demonstrated that fat-storing cells (hepatic stellate cells-HSCs) participate in schistosomal granuloma fibrogenesis. The origin of such cells in portal areas, away from the Disse spaces, was herein investigated. HSCs were identified in frozen sections of the liver by means of Sudan III staining. They appeared as red-stained cells disposed along the sinusoids of normal mice, but were never found within portal spaces. However, in the chronically inflamed portal spaces of Capillaria hepatica-infected mice, Sudan III-positive cells were frequently present among leukocytes and fibroblast-like cells. Thus, there are no resident HSCs in portal spaces, but their presence there in chronic inflammatory processes indicates that they are able to migrate from peri-sinusoidal areas in order to reach the portal areas.

Preliminary study of the presence of antibodies against excretory-secretory antigens from protoscoleces of Echinococcus granulosus in dogs with intestinal echinococcosis

The aim of the present study was to analyze the antibody response against excretory-secretory antigens (ES-Ag) from Echinococcus granulosus protoscoleces, using sera from dogs infected with E. granulosus and other helminths. ES-Ag were obtained from the first 50 h maintenance of protoscoleces in vitro. Immunochemical characterization was performed by immunoblotting with sera from dogs naturally infected with E. granulosus (n = 12), sera from dogs infected with helminths other than E. granulosus (n = 30), and helminth-free dog sera (n = 20). These findings were compared to those obtained from a somatic extract of protoscoleces (S-Ag). ES-Ag only showed four cross-reacting proteins of 65, 61, 54, and 45-46 kDa. Antigens with apparent masses of 89 and 50 kDa in ES-Ag and of 130 and 67 kDa in S-Ag were identified by sera of dogs infected with E. granulosus only, whereas a protein of 41-43 kDa was recognised by the majority of the sera from dogs with non-echinococcal infection. Employing ELISA to study the same sera, S-Ag revealed higher immunoreactivity than ES-Ag, but also showed higher cross-reactivity levels when sera from dogs with non-echinococcal infection were assayed in immunoblotting.

Fluorescence imaging reveals the nuclear behavior of peroxisome proliferator-activated receptor/retinoid X receptor heterodimers in the absence and presence of ligand.

In a global approach combining fluorescence recovery after photobleaching (FRAP), fluorescence correlation spectroscopy (FCS), and fluorescence resonance energy transfer (FRET), we address the behavior in living cells of the peroxisome proliferator-activated receptors (PPARs), a family of nuclear receptors involved in lipid and glucose metabolism, inflammation control, and wound healing. We first demonstrate that unlike several other nuclear receptors, PPARs do not form speckles upon ligand activation. The subnuclear structures that may be observed under some experimental conditions result from overexpression of the protein and our immunolabeling experiments suggest that these structures are subjected to degradation by the proteasome. Interestingly and in contrast to a general assumption, PPARs readily heterodimerize with retinoid X receptor (RXR) in the absence of ligand in living cells. PPAR diffusion coefficients indicate that all the receptors are engaged in complexes of very high molecular masses and/or interact with relatively immobile nuclear components. PPARs are not immobilized by ligand binding. However, they exhibit a ligand-induced reduction of mobility, probably due to enhanced interactions with cofactors and/or chromatin. Our study draws attention to the limitations and pitfalls of fluorescent chimera imaging and demonstrates the usefulness of the combination of FCS, FRAP, and FRET to assess the behavior of nuclear receptors and their mode of action in living cells.