Indoor air microbiological evaluation of offices, hospitals, industries, and shopping centers

In this study it was compared the MAS-100 and the Andersen air samplers' performances and a similar trend in both instruments was observed. It was also evaluated the microbial contamination levels in 3060 samples of offices, hospitals, industries, and shopping centers, in the period of 1998 to 2002, in Rio de Janeiro city. Considering each environment, 94.3 to 99.4% of the samples were the allowed limit in Brazil (750 CFU/m³). The industries' results showed more important similarity among fungi and total heterotrophs distributions, with the majority of the results between zero and 100 CFU/m³. The offices' results showed dispersion around 300 CFU/m³. The hospitals' results presented the same trend, with an average of 200 CFU/m³. Shopping centers' environments showed an average of 300 CFU/m³ for fungi, but presented a larger dispersion pattern for the total heterotrophs, with the highest average (1000 CFU/m³). It was also investigated the correlation of the sampling period with the number of airborne microorganisms and with the environmental parameters (temperature and air humidity) through the principal components analysis. All indoor air samples distributions were very similar. The temperature and air humidity had no significant influence on the samples dispersion patterns.

Single and concomitant experimental infectionsby Endotrypanum spp. and Leishmania (Viannia) guyanensis (Kinetoplastida: Trypanosomatidae) in the Neotropical sand fly Lutzomyia longipalpis (Diptera: Psychodidae)

Lutzomyia longipalpis females received single and mixed infections with Endotrypanum and Leishmania. Two biological parameters were analyzed: the percentage of infected females and the distribution of flagellates in the gut of the females. The principal comparisons were performed between (1) two strains of Endotrypanum, (2) cloned versus primary sample of one strain of Endotrypanum, (3) Endotrypanum versus Leishmania guyanensis, and (4) the pattern of flagellates behaviour by optical microscopy in females with single or mixed infection versus the identification of parasites isolated from digestive tracts by isoenzyme electrophoresis. Flagellates of Endotrypanum showed distinct patterns of infection suggesting that there is variation between and within strains. The distribution of Endotrypanum and L. guyanensis differed significantly in relation to the colonization of the stomodeal valve. In co-infection with L. guyanensis, a large number of flagellates were seen to be plentifully infecting the stomodeal valve in significantly more specimens than in females infected by Endotrypanum only. However, the electrophoretic profiles of isoenzymes of parasites recovered from all co-infected specimens corresponded to Endotrypanum. This suggests that the mere correlation sand fly infection-biochemical analysis of isolates may induce parasitological incorrect consideration.

Trypanosoma cruzi: blood parasitism kinetics and their correlation with heart parasitism intensity during long-term infection of Beagle dogs

The goals of the present study were to evaluate the kinetics of blood parasitism by examination of fresh blood, blood culture (BC) and PCR assays and their correlation with heart parasitism during two years of infection in Beagle dogs inoculated with the Be-78, Y and ABC Trypanosoma cruzi strains. Our results showed that the parasite or its kDNA is easily detected during the acute phase in all infected animals. On the other hand, a reduced number of positive tests were verified during the chronic phase of the infection. The frequency of positive tests was correlated with T. cruzi strain. The percentage of positive BC and blood PCR performed in samples from animals inoculated with Be-78 and ABC strains were similar and significantly larger in relation to animals infected with the Y strain.Comparison of the positivity of PCR tests performed using blood and heart tissue samples obtained two years after infection showed two different patterns associated with the inoculated T. cruzi strain: (1) high PCR positivity for both blood and tissue was observed in animals infected with Be-78 or ABC strains; (2) lower and higher PCR positivity for the blood and tissue, respectively, was detected in animals infected with Y strains. These data suggest that the sensitivity of BC and blood PCR was T. cruzi strain dependent and, in contrast, the heart tissue PCR revealed higher sensitivity regardless of the parasite stock.

Experimental infection parameters in Galea spixii (Rodentia: Caviidae) with Leishmania infantum chagasi

In order to better understand the epidemiological transmission network of leishmaniasis, an endemic disease in Northeast Brazil, we investigated the susceptibility of Spix yellow-toothed cavies (Galea spixii) to the Leishmania infantum chagasi parasite. Nine cavies were experimentally infected, separated into three groups and monitored at 30, 90 and 180 days, respectively. Amastigotes were identified in the spleen slides of two cavies killed 180 days after infection. Antibodies against the L. i. chagasi were identified in one of the cavies. This demonstrates that G. spixii is in fact capable of maintaining a stable infection by L. i. chagasi without alterations in biochemical and hematological parameters of the host and without perceivable micro and macroscopic lesions.

Genetic variability in the 5' UTR and NS5A regions of hepatitis C virus RNA isolated from non-responding and responding patients with chronic HCV genotype 1 infection

Sequence variation among different hepatitis C virus (HCV) isolates has adaptive significance and reflects the modes and intensities of selection mechanisms operating on the virus. In this work, we sought to investigate using classical population genetics parameters, the genetic variability of HCV genotype 1 using the 5' UTR and NS5A regions from treatment non-responding and responding groups of patients. Both regions showed low genetic varia-bility and the 5' UTR showed neutral deviation. No differences were observed in the nonsynonymous/synonymous nucleotide substitution ratio among groups for NS5A. The analysis of molecular variance test of the 5' UTR region showed an 11.94% variation among groups. Phylogenetic analysis showed no correlation between sequence variations and therapeutic responses.

Relationship among epidemiological parameters of six childhood infections in a non-immunized Brazilian community

Epidemiological parameters, such as age-dependent force of infection and average age at infection () were estimated for rubella, varicella, rotavirus A, respiratory syncytial virus, hepatitis A and parvovirus B19 infections for a non-immunized Brazilian community, using the same sera samples. The for the aforementioned diseases were 8.45 years (yr) [95% CI: (7.23, 9.48) yr], 3.90 yr [95% CI: (3.51, 4.28) yr], 1.03 yr [95% CI: (0.96, 1.09) yr], 1.58 yr [95% CI: (1.39, 1.79) yr], 7.17 yr [95% CI: (6.48, 7.80) yr] and 7.43 yr [95% CI: (5.68, 9.59) yr], respectively. The differences between average ages could be explained by factors such as differences in the effectiveness of the protection conferred to newborns by maternally derived antibodies, competition between virus species and age-dependent host susceptibility. Our seroprevalence data may illustrate a case of the above-mentioned mechanisms working together within the same population.

Correlation of biological serum markers with the degree of hepatic fibrosis and necroinflammatory activity in hepatitis C and schistosomiasis patients

Liver biopsy is the gold-standard method to stage fibrosis; however, it is an invasive procedure and is potentially dangerous. The main objective of this study was to evaluate biological markers, such as cytokines IL-13, IFN-γ, TNF-α and TGF-β, platelets, bilirubins (Bil), alanine aminotransferase (ALT) and aspartate aminotransferase (AST), total proteins, γ-glutamil transferase (γ-GT) and alkaline phosphatase (AP), that could be used to predict the severity of hepatic fibrosis in schistosomiasis and hepatitis C (HC) as isolated diseases or co-infections. The following patient groups were selected: HC (n = 39), HC/hepatosplenic schistosomiasis (HSS) (n = 19), HSS (n = 22) and a control group (n = 13). ANOVA and ROC curves were used for statistical analysis. P < 0.05 was considered significant. With HC patients we showed that TNF-α (p = 0.020) and AP (p = 0.005) could differentiate mild and severe fibrosis. With regard to necroinflammatory activity, AST (p = 0.002), γ-GT (p = 0.034) and AP (p = 0.001) were the best markers to differentiate mild and severe activity. In HC + HSS patients, total Bil (p = 0.008) was capable of differentiating between mild and severe fibrosis. In conclusion, our study was able to suggest biological markers that are non-invasive candidates to evaluate fibrosis and necroinflammatory activity in HC and HC + HSS.

Immunological and parasitological parameters after treatment with dexamethasone in murine Schistosoma mansoni

This work aimed to evaluate the effect of diphenyl dimethyl bicarboxylate (DDB) and dexamethasone alone and in combination with praziquantel on various parasitological, immunological and pathological parameters reflecting disease severity and morbidity in murine schistosomiasis. DDB and dexamethasone had no effect on worm burden but altered tissue egg distribution. This indicates that, under the schedule used, neither drug interfered with the development of adult worms or oviposition, but both can modulate liver pathology. Dexamethasone resulted in a greater reduction in granuloma size than did DDB. Dexamethasone-treated mice also showed lower levels of serum gamma interferon (IFN-γ), interleukin-12 (IL-12) and IL-4, together with higher IL-10 levels, than infected untreated control animals. These data suggest that dexamethasone is a convenient and promising coadjuvant agent that results in decreased morbidity in murine schistosomiasis.

Confirmation of Anopheles (Anopheles) calderoni Wilkerson, 1991 (Diptera: Culicidae) in Colombia and Ecuador through molecular and morphological correlation with topotypic material

The morphologically similar taxa Anopheles calderoni, Anopheles punctimacula, Anopheles malefactor and Anopheles guarao are commonly misidentified. Isofamilies collected in Valle de Cauca, Colombia, showed morphological characters most similar to An. calderoni, a species which has never previously been reported in Colombia. Although discontinuity of the postsubcostal pale spots on the costa (C) and first radial (R1) wing veins is purportedly diagnostic for An. calderoni, the degree of overlap of the distal postsubcostal spot on C and R1 were variable in Colombian specimens (0.003-0.024). In addition, in 98.2% of larvae, seta 1-X was located off the saddle and seta 3-C had 4-7 branches in 86.7% of specimens examined. Correlation of DNA sequences of the second internal transcribed spacer and mtDNA cytochrome c oxidase subunit I gene (COI) barcodes (658 bp of the COI gene) generated from Colombian progeny material and wild-caught mosquitoes from Ecuador with those from the Peruvian type series of An. calderoni confirmed new country records. DNA barcodes generated for the closely related taxa, An. malefactor and An. punctimacula are also presented for the first time. Examination of museum specimens at the University of the Valle, Colombia, revealed the presence of An. calderoni in inland localities across Colombia and at elevations up to 1113 m.

Correlation between koilocytes and human papillomavirus detection by PCR in oral and oropharynx squamous cell carcinoma biopsies

The purpose of this study was to compare the histopathological analysis with polymerase chain reaction (PCR) methods to predict the presence of human papillomavirus (HPV) infection in oral squamous cell carcinoma biopsies. Eighty-three paraffin-embedded tissue specimens from patients with oropharynx and mouth floor squamous cell carcinoma were submitted to histopathological analysis under light microscopy, specifically for the determination of the presence of koilocytes. Subsequently, DNA was purified from the same paraffin-embedded specimens and submitted to PCR. Fisher's exact test showed no statistically significant correlation between the two methods. The results suggest that the presence of koilocytes is unreliable for the detection of HPV presence in oral and oropharynx squamous cell carcinoma.

Correlation of meta 1 expression with culture stage, cell morphology and infectivity in Leishmania (Leishmania) amazonensis promastigotes

The parasitic protozoan Leishmania (Leishmania) amazonensis alternates between mammalian and insect hosts. In the insect host, the parasites proliferate as procyclic promastigotes andthen differentiate into metacyclic infective forms. The meta 1 gene is preferentially expressed during metacyclogenesis. Meta 1 expression profile determination along parasite growth curves revealed that the meta 1 mRNA level peaked at the early stationary phase then decreased to an intermediate level. No correlation was observed between meta 1 expression and infectivity. Conversely, infectivity correlated with the increase of apoptotic cells in the late stationary phase.

Acute experimental Trypanosoma cruzi infection: establishing a murine model that utilises non-invasive measurements of disease parameters

Trypanosoma cruzi infection has a large public health impact in Latin American countries. Although the transmission rates via blood transfusions and insect vectors have declined sharply in the past 20 years due to policies of the Southern Cone countries, a large number of people are still at risk for infection. Currently, no accepted experimental model or descriptions of the clinical signs that occur during the course of acute murine infection are available. The aim of this work was to use non-invasive methods to evaluate the clinical signs of Balb/c mice infected with the Y strain of T. cruzi. The infected mice displayed evident clinical changes beginning in the third week of infection. The mice were evaluated based on physical characteristics, spontaneous activity, exploratory behaviour and physiological alterations. We hope that the results presented in this report provide parameters that complement the effective monitoring of trypanocidal treatment and other interventions used to treat experimental Chagas disease.

Antiviral therapy against chronic hepatitis B in Brazil: high rates of lamivudine resistance mutations and correlation with HBV genotypes

The effectiveness of antiviral treatments of chronic hepatitis B has been poorly studied in Brazil. Here, hepatitis B virus (HBV) DNA positivity, drug resistance mutations and their association with HBV genotypes were evaluated in chronically HBV-infected patients under different drug regimens in Brazil. The study involved 129 patients under interferon or nucleos(t)ide analogue therapy for a median treatment time of 12 months. One hundred and five (81%) of these patients were treated with lamivudine (LAM), either in monotherapy or in combination with newer drugs, such as entecavir (ETV) or tenofovir (TDF). High (37.5-100%) rates of HBV DNA positivity were observed with all but one drug regimen (LAM + ETV). However, patients that were treated with ETV alone, TDF alone or with LAM combination therapies had a mean viral load that was 3-4 log lower than patients treated with LAM monotherapy. Of the patients treated with LAM, 47% developed resistance mutations. HBV genotypes A (59.1%), D (30.3%) and F (9.1%) were found. There was no association between the presence of LAM resistance mutations and genotypes, HBeAg status or treatment duration. Nevertheless, the rtM204V mutation was observed more frequently (12/13, 92%) in genotype A than in the others (p = 0.023). Six out of nine isolates that contained the rtM204I mutation belonged to genotype D and half of them displayed a single mutation. Genotype D isolates with the rtM204V variant preferentially displayed a triple mutation, while genotype A preferentially displayed a double mutation (p = 0.04).

Brazilian clinical trial of uniform multidrug therapy for leprosy patients: the correlation between clinical disease types and adverse effects

This study sought to verify the correlation between leprosy types and the adverse effects of treatment drugs. This quantitative, prospective, nested study was developed at the Dona Libânia Dermatology Centre in Fortaleza, Brazil. Data were collected from November 2007-November 2008. During this period, 818 leprosy patients were diagnosed and began treatment. Forty patients with tuberculoid leprosy (TT) were selected. Twenty patients followed a standard therapy of dapsone and rifampicin and 20 were administered dapsone, rifampicin and clofazimine (U-MDT). Twenty patients with borderline lepromatous (BL) and lepromatous leprosy (LL) were also selected and treated with U-MDT. All of the subjects received six doses. With the exception of haemolytic anaemia, there was a low incidence of adverse effects in all the groups. We did not observe any differences in the incidence of haemolytic anaemia or other side effects across groups of patients with TT, BL or LL treated with U-MDT.

Detection of replication-defective hepatitis A virus based on the correlation between real-time polymerase chain reaction and ELISA in situ results

ELISA in situ can be used to titrate hepatitis A virus (HAV) particles and real-time polymerase chain reaction (RT-PCR) has been shown to be a fast method to quantify the HAV genome. Precise quantification of viral concentration is necessary to distinguish between infectious and non-infectious particles. The purpose of this study was to compare cell culture and RT-PCR quantification results and determine whether HAV genome quantification can be correlated with infectivity. For this purpose, three stocks of undiluted, five-fold diluted and 10-fold diluted HAV were prepared to inoculate cells in a 96-well plate. Monolayers were then incubated for seven, 10 and 14 days and the correlation between the ELISA in situ and RT-PCR results was evaluated. At 10 days post-incubation, the highest viral load was observed in all stocks of HAV via RT-PCR (10(5) copies/mL) (p = 0.0002), while ELISA revealed the highest quantity of particles after 14 days (optical density = 0.24, p < 0.001). At seven days post-infection, there was a significant statistical correlation between the results of the two methods, indicating equivalents titres of particles and HAV genome during this period of infection. The results reported here indicate that the duration of growth of HAV in cell culture must be taken into account to correlate genome quantification with infectivity.