Low dose of fine particulate matter (PM2.5) can induce acute oxidative stress, inflammation and pulmonary impairment in healthy mice

Air pollution is associated with morbidity and mortality induced by respiratory diseases. However, the mechanisms therein involved are not yet fully clarified. Thus, we tested the hypothesis that a single acute exposure to low doses of fine particulate matter (PM2.5) may induce functional and histological lung changes and unchain inflammatory and oxidative stress processes. PM2.5 was collected from the urban area of Sao Paulo city during 24 h and underwent analysis for elements and polycyclic aromatic hydrocarbon contents. Forty-six male BALB/c mice received intranasal instillation of 30 mu L of saline (CTRL) or PM2.5 at 5 or 15 mu g in 30 mu L of saline (P5 and P15, respectively). Twenty-four hours later, lung mechanics were determined. Lungs were then prepared for histological and biochemical analysis. P15 group showed significantly increased lung impedance and alveolar collapse, as well as lung tissue inflammation, oxidative stress and damage. P5 presented values between CTRL and P15: higher mechanical impedance and inflammation than CTRL, but lower inflammation and oxidative stress than P15. In conclusion, acute exposure to low doses of fine PM induced lung inflammation, oxidative stress and worsened lung impedance and histology in a dose-dependent pattern in mice.

Cholinergic Hyperresponsiveness of Peripheral Lung Parenchyma in Chronic Obstructive Pulmonary Disease

Background: Up to 60% of chronic obstructive pulmonary disease ( COPD) patients can present airway hyperresponsiveness. However, it is not known whether the peripheral lung tissue also shows an exaggerated response to agonists in COPD. Objectives: To investigate the in vitro mechanical behavior and the structural and inflammatory changes of peripheral lung tissue in COPD patients and compare to nonsmoking controls. Methods: We measured resistance and elastance at baseline and after acetylcholine (ACh) challenge of lung strips obtained from 10 COPD patients and 10 control subjects. We also assessed the alveolar tissue density of neutrophils, eosinophils, macrophages, mast cells and CD8+ and CD4+ cells, as well as the content of alpha-smooth muscle actin-positive cells and elastic and collagen fibers. We further investigated whether changes in in vitro parenchymal mechanics correlated to structural and inflammatory parameters and to in vivo pulmonary function. Results: Values of resistance after ACh treatment and the percent increase in tissue resistance (%R) were higher in the COPD group (p <= 0.03). There was a higher density of macrophages and CD8+ cells (p < 0.05) and a lower elastic content (p = 0.003) in the COPD group. We observed a positive correlation between %R and eosinophil and CD8+ cell density (r = 0.608, p = 0.002, and r = 0.581, p = 0.001, respectively) and a negative correlation between %R and the ratio of forced expiratory volume in 1 s to forced vital capacity (r = -0.451, p < 0.05). Conclusions: The cholinergic responsiveness of parenchymal lung strips is increased in COPD patients and seems to be related to alveolar tissue eosinophilic and CD8 lymphocytic inflammation and to the degree of airway obstruction on the pulmonary function test. Copyright (C) 2011 S. Karger AG, Basel

Pulmonary function and histological impairment in mice after acute exposure to aluminum dust

Along the aluminum refining process, alumina (Al(2)O(3)) constitutes the main source of dust. Although aluminum refinery workers present respiratory symptoms with lung functional changes, no conclusive data about lung function impairment after alumina exposure has been so far reported. We examined the pulmonary alterations of exposure to material collected in an aluminum refinery in Brazil. BALB/c mice were exposed in a whole-body chamber for 1 h to either saline (CTRL, n = 11) or to a suspension (in saline) of 8 mg/m(3) of the dust (ALUM, n = 11) both delivered by an ultrasonic nebulizer. Twenty-four hours after exposure lung mechanics were measured by the end-inflation method. Lungs were prepared for histology. ALUM showed significantly higher static elastance (34.61 +/- 5.76 cmH(2)O/mL), elastic component of viscoelasticity (8.16 +/- 1.20 cmH(2)O/mL), pressure used to overcome the resistive component of viscoelasticity (1.62 +/- 0.24 cmH(2)O), and total resistive pressure (2.21 +/- 0.49 cmH(2)O) than CTRL (27.95 +/- 3.63 cmH(2)O/mL, 6.12 +/- 0.99 cmH(2)O/mL, 1.23 +/- 0.19 cmH(2)O, and 1.68 +/- 0.23 cmH(2)O, respectively). ALUM also presented significantly higher fraction area of alveolar collapse (69.7 +/- 1.2%) and influx of polymorphonuclear cells (27.5 +/- 1.1%) in lung parenchyma than CTRL (27.2 +/- 1.1% and 14.6 +/- 0.7%, respectively). The composition analysis of the particulate matter showed high concentrations of aluminum. For the first time it was demonstrated in an experimental model that an acute exposure to dust collected in an aluminum producing facility impaired lung mechanics that could be associated with inflammation.

A prospective study on the dynamics of the clinical and immunological evolution of human Leishmania (L.) infantum chagasi infection in the Brazilian Amazon region

This prospective study was carried out from October 2003 to December 2005 and involved a cohort of 946 individuals of both genders, aged 1-89 years, from an endemic area for American visceral leishmaniasis (AVL), in Para State, Brazil. The aim of the study was to analyze the dynamics of the clinical and immunological evolution of human Leishmania ( L.) infantum chagasi infection represented by the following clinical-immunological profiles: asymptomatic infection (AI); symptomatic infection (SI = AVL); subclinical oligosymptomatic infection (SOI); subclinical resistant infection (SRI); and indeterminate initial infection (III). Infection diagnosis was determined by the indirect fluorescent antibody test and leishmanin skin test. In total, 231 cases of infection were diagnosed: the AI profile was the most frequent (73.2%), followed by SRI (12.1%), III (9.9%), SI (2.6%) and SOI (2.2%). The major conclusion regarding evolution dynamics was that the III profile plays a pivotal role from which the cases evolve to either the resistant, SRI and AI, or susceptible, SOI and SI, profiles; only one of the 23 III cases evolved to SI, while most evolved to either SRI (nine cases) or SOI (five cases) and eight cases remained as III. (C) 2010 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

Characterization of cytotoxic immune response in skin and mucosal lesions of paracoccidioidomycosis

Background: CD8+ T cells and natural killer (NK) cells are involved in the immune response against some pathogens. For this purpose, we investigated the in situ paracoccidioidomycosis (PCM) immune response addressing the participation of NK cells, CD8+ T cells, perforin and granzyme B expression. Methods: Sixty biopsies of PCM skin and mucosa were classified according to the presence of compact granulomas (G1), poorly organized granulomas (G2) and both kinds in the same lesion (G3). CD8+ T cells, NK cells, perforin and granzyme B were showed by immunohistochemistry. Results: CD8+ T cells were increased over NK cells in cutaneous G1 and G2 lesions. There was no difference regarding such cells in G3 lesions, although they were abundant in such lesions. In mucosa, CD8+ T cells were increased in number over NK cells in all groups. Granzyme B in skin increased in G2 and G3. The number of granzyme did not differ in mucosal lesions in the three groups. Conclusions: CD8+ T cells and NK cells play a role in PCM cutaneous and mucosal lesions. The predominance of CD8+ T cells over NK cells may represent an effective response against the fungi. Moreover, the high number of granzyme B expressing cells corroborates this possibility.

Fatal gemcitabine-induced pulmonary toxicity in metastatic gallbladder adenocarcinoma

Gemcitabine is a chemotherapy agent that may cause unpredictable side effects. In this report, we describe a fatal gemcitabine-induced pulmonary toxicity in a patient with gallbladder metastatic adenocarcinoma. A 72-year-old patient was submitted to an elective laparoscopic cholecystectomy, and a tubular adenocarcinoma in the gallbladder was incidentally diagnosed. CT scan and ultrasound before the surgery did not show any tumor. After the surgery a Pet scan was positive for a hot-spot in the left colon. The colonic lesion was conveniently removed and the histology evaluation confirmed the diagnosis of adenocarcinoma tubular. The patient was then submitted to three sections of 1,600 mg/m(2) of gemcitabine with intervals of 1 week. Three weeks later he developed severe respiratory distress. A helicoidal CT scan showed diffuse and severe interstitial pneumonitis, and lung biopsy confirmed accelerated usual interstitial pneumonia consistent with drug-induced toxicity. The patient presented unfavorable evolution with progressive worsening of respiratory function, hypotension, and renal failure. He died 1 month later in spite of methylprednisolone pulse therapy, large spectrum antimicrobial therapy, and full support of respiratory, hemodynamic and renal systems. Gemcitabine-induced pulmonary toxicity is usually a dramatic condition. Physicians should suspect pulmonary toxicity in patients with respiratory distress after gemcitabine chemotherapy, mainly in elderly patients.

Increased mRNA expression of collagen V gene in pulmonary fibrosis of systemic sclerosis

Background Collagen V shows promise as an inducer of interstitial lung fibrosis in experimental systemic sclerosis (SSc). Materials and methods Remodelling of the pulmonary interstitium was evaluated based on the clinical data and open lung biopsies from 15 patients with SSc. Normal lung tissues obtained from eight individuals who died of traumatic injuries were used as control group. Immunofluorescence, immunohistochemistry, morphometry, tri-dimensional reconstruction and a real-time polymerase chain reaction were used to evaluate the quantity, structure and molecular chains of collagen V. The impact of these markers was tested on clinical data. Results The main difference in collagen V content between SSc patients and the control group was an increased, abnormal and distorted fibre deposition in the alveolar septa and the pre-acinar artery wall. The lungs from SSc patients presented [alpha 1(V)] and [alpha 2(V)] mRNA chain expression increased, but [alpha 2(V)] was proportionally increased compared with the control group. High levels of collagen V were inversely associated with vital capacity (r = -0.72; P = 0.002), forced vital capacity (r = -0.76; P < 0.001), forced expiratory volume in 1-s (r = -0.89; P < 0.001) and diffusing capacity for carbon monoxide (r = -0.62; P = 0.04). Conclusions Abnormal collagen V fibres are overproduced in lungs from SSc patients and may play an important role in the pathogenesis of the disease as this molecule regulates tissue collagen assembly. The aberrant histoarchitecture observed in SSc can be related to the overexpression of the [alpha 2(V)] gene of unknown origin.

Further evidences on a new diagnostic approach for monitoring human Leishmania (L.) infantum chagasi infection in Amazonian Brazil

This was a prospective study carried out during a period over 2 years (May/2006-September/2008) with a cohort of 1,099 individuals of both genders, aged 1 year old and older, from an endemic area of American visceral leishmaniasis (AVL) in Para state, Brazil. The object was to analyze the prevalence and incidence of human Leishmania (L.) infantum chagasi infection as well as the dynamics evolution of its clinical-immunological profiles prior identified: (1) asymptomatic infection (AI); (2) symptomatic infection (SI = AVL); (3) sub-clinical oligosymptomatic infection (SOI); (4) sub-clinical resistant infection (SRI) and; (5) indeterminate initial infection (III). The infection diagnosis was performed by using both the indirect fluorescent antibody test and leishmanin skin test with amastigotes and promastigotes antigens of L. (L.) i. chagasi, respectively. A total of 187 cases of infection were recorded in the prevalence (17%), 117 in the final incidence (6.9%), and 304 in the accumulated prevalence (26.7%), which provided the following distribution into the clinical-immunological profiles: AI, 51.6%; III, 22.4%; SRI, 20.1%; SOI, 4.3%; and SI (=AVL), 1.6%. The major finding regarding the dynamics evolution of infection was concerned to III profile, from which the cases of infection evolved to either the resistant profiles, SRI (21 cases, 30.8%) and AI (30 cases, 44.1%), or the susceptible SI (=AVL; 1 case, 1.5%); the latter 16 cases remained as III till the end of the study. These results provided the conclusion that this diagnostic approach may be useful for monitoring human L. (L.) i. chagasi infection in endemic area and preventing the high morbidity of severe AVL cases.

A cross-sectional study on the clinical and immunological spectrum of human Leishmania (L.) infantum chagasi infection in the Brazilian Amazon region

The objectives of this study were to identify individuals with symptomatic and/or asymptomatic infection due to Leishmania (L.) infantum chagasi; to study the two types of infection, both clinically and immunologically, and to determine the prevalence rate of infection at the beginning of the study. This was a cross-sectional study with a cohort of 946 individuals, of both genders, from the age of 1 year, living in the municipality of Barcarena, PA, Brazil, an area endemic for American visceral leishmaniasis (AVL). The leishmanin skin test (LST) and the indirect fluorescent test (IFAT), were used for the diagnosis of infection. One hundred and twenty cases of infection were diagnosed, with a prevalence rate of 12.6%; eight cases showed high seroreactivity (1280-10240, IgG) in IFAT and no LST reaction; four of these cases were typical AVL and four had subclinical oligosymptomatic infection. Using two immunological methods with a clinical examination of the infected individuals enabled the identification of five clinical-immunological profiles which may promote a better understanding of the interaction between L. (L.) i. chagasi and the human immune response: asymptomatic infection (AI) 73.4%; subclinical resistant infection (SRI) 15%; subclinicat oligosymptomatic infection (SOI) 3%; symptomatic infection (AVL) 3% and indeterminate initial infection (III) 5%. (C) 2009 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

Effects of Salivary Gland Homogenate from Wild-Caught and Laboratory-Reared Lutzomyia longipalpis on the Evolution and Immunomodulation of Leishmania (Leishmania) amazonensis Infection

We investigated the effects of Lutzomyia longipalpis salivary glands homogenate of wild-caught and laboratory-reared vectors on the lesion evolution and immunomodulation of the infection caused by Leishmania (Leishmania) amazonensis. To compare the effect of both salivary glands homogenate (SGH), C57BL/6 mice were inoculated Subcutaneously into the hind footpads or into the ear dermis with 10(6) promastigotes in the presence or not of SGH from wild-caught and laboratory-colonized sand flies. Comparing SGH groups, the lesion size was lower in mice co-inoculated with wild-caught SGH, as the parasitism and the infiltration of macrophages at the inoculation site. Wild-caught SGH also determined lower production of IL-4 and IL-10 but higher IL-12 levels compared with laboratory-reared SGH. Our findings address a probable bias by using SGH from laboratory-colonized sand flies instead of wild-caught vector SGH in studies concerning saliva effects. A possible mild influence of sand fly saliva in natural infections caused by Leishmania is also speculated, as infection is transmitted by wild and not by laboratory-reared vectors.

Pulmonary periarterial inflammation in fatal asthma

P>Background To date, little information has been available about pulmonary artery pathology in asthma. The pulmonary artery supplies the distal parts of the lungs and likely represents a site of immunological reaction in allergic inflammation. The objective of this study was to describe the inflammatory cell phenotype of pulmonary artery adventitial inflammation in lung tissue from patients who died of asthma. Methods We quantified the different inflammatory cell types in the periarterial region of small pulmonary arteries in lung tissue from 22 patients who died of asthma [fatal asthma (FA)] and 10 control subjects. Using immunohistochemistry and image analysis, we quantified the cell density for T lymphocytes (CD3, CD4, CD8), B lymphocytes (CD20), eosinophils, mast cells (chymase and tryptase), and neutrophils in the adventitial layer of pulmonary arteries with a diameter smaller than 500 mu m. Results Our data (median/interquartile range) demonstrated increased cell density of mast cells [FA=271.8 (148.7) cells/mmpulmonary artery participates in the inflammatory process in FA, demonstrating increased infiltration of mast cells, eosinophils, and neutrophils, but not of T and B lymphocytes.

Saliva of laboratory-reared Lutzomyia longipalpis exacerbates Leishmania (Leishmania) amazonensis infection more potently than saliva of wild-caught Lutzomyia longipalpis

In order to compare the saliva effect from wild-caught and lab-reared L. longipalpis on the development of experimental cutaneous leishmaniasis, C57BL/6 mice were inoculated subcutaneously into the hind footpads with promastigotes of L (L.) amazonensis Plus salivary gland lysate from wild-caught (SGL-W) and lab-colonized (SGL-C) vectors. Lesion sizes were significantly larger in the mice infected with both saliva compared to mice infected with parasites alone; moreover, the lesions caused by parasite+SGL-C were significantly larger than the lesions caused by parasite+SGL-W. Histopathological morphometric studies regarding the acute phase of infections showed lower numbers of polymorphonuclear cells, greater numbers of mononuclear cells and parasites in SGL-C infected mice compared to SGL-W infected mice. In the chronic phase of infection, the number of mononuclear cells was lower and the number of parasites was greater in SGL-C infected mice than SGL-W infected mice. In vitro studies showed increased infection index of macrophages infected with parasites plus saliva compared to infection with parasites alone, with no difference between the saliva infection indices. SDS-PAGE gel for SGL-C and SGL-W showed differences in the composition and quantity of protein bands, determined by densitometry. These results call attention to the experimental saliva model, which shows exacerbation of infection caused by sandfly saliva. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

CD1a and Factor XIIIa Immunohistochemistry in Leprosy: A Possible Role of Dendritic Cells in the Pathogenesis of Mycobacterium leprae Infection

Leprosy is a curable chronic granulomatous infectious disease caused by the bacillus Mycobacterium leprae. This organism has a high affinity for skin and peripheral nerve cells. In the evolution of infections, the immune status of patients determines the disease expression. Dendritic cells are antigen-presenting cells that phagocytose particles and microorganisms. In skin, dendritic cells are represented by epidermal Langerhans cells and dermal dendrocytes, which can be identified by expression of CD1a and factor XIIIa (FXIIIa). In the present study, 29 skin samples from patients with tuberculoid (13 biopsies) and lepromatous (16 biopsies) leprosy were analyzed by immunohistochemistry using antibodies to CD1a and FXIIIa. Quantitative analysis of labeling pattern showed a clear predominance of dendritic cells in tuberculoid leprosy. Difference between the number of positive cells of immunohistochemistry for the CD1a and FXIIIa staining observed in this study indicates a role for dendritic cells in the cutaneous response to leprosy. Dendritic cells may be a determinant of the course and clinical expression of the disease.

Description of Nosocomial Infection Prevention Practices by Anesthesiologists in a University Hospital

Kishi D; Videira RLR Description of Nosocomial Infection Prevention Practices by Anesthesiologists in a University Hospital. Background and objectives: Anesthesiologists play an important role in the prevention of nosocomial infections. In anesthetic practice, physiologic barriers are routinely breached, allowing patient contamination with microorganisms and the consequent development of infection. The lack of adhesion to recommended practices can facilitate transmission of microorganisms. It is important to describe prophylactic practices of anesthesia-related nosocomial infections performed by anesthesiologists. Methods: Structured questionnaires were distributed to be answered voluntarily and anonymously by anesthesiologists. Results: Among 112 anesthesiologists, 75% answered the questionnaire. Surgical mask is used by 95.2% of anesthesiologists, 96.3% wear gloves frequently, 98.9% wear sterile gloves for neuraxial block, 91.3% use sterile technique for central venous puncture, 95.1% wash their hands between cases, 91.6% try to maintain the endotracheal tube sterile, 96.3% discard the prefilled propofol syringe at the end of each anesthesia, 30% clean the vials before using it in the neuraxial blocks, and 19.8% clean the vials before intravenous use. Conclusions: Respondents showed good adhesion to practices of nosocomial infection prophylaxis and to improve them educational multidisciplinary campaigns are necessary.

Hepatitis Delta virus genotype 8 infection in Northeast Brazil: Inheritance from African slaves?

Hepatitis Delta virus (HDV) is endemic worldwide, but its prevalence varies in different geographical areas. While in the Brazilian Amazon, HDV is known to be endemic and to represent a significant public health problem, few studies have assessed its prevalence in other regions in the country. This study evaluated the seroprevalence of HDV among HBsAg chronic carriers from Maranhao state, a region located in the Northeast of Brazil. Among 133 patients, 5 had anti-HD, of whom 3 had HDV RNA. HDV genotypes were characterized by Bayesian phylogenetic analysis of nucleotide sequences from the HDAg coding region. HDV-3 was identified in one patient who lives in Maranhao, but was born in Amazonas state (Western Amazon basin). Phylogenetic analysis shows that this HDV-3 sequence grouped with other HDV-3 sequences isolated in this state, which suggests that the patient probably contracted HDV infection there. Surprisingly, the other two patients were infected with HDV-8, an African genotype. These patients were born and have always lived in Urbano Santos, a rural county of Maranhao state, moreover they had never been to Africa and denied any contact with people from that continent. This is the first description of the HDV-8 in non-native African populations. This genotype may have been introduced to Brazil through the slaves brought to the country from the West Africa regions during the 16-18th centuries. Our results indicate that the need of clinical and epidemiological studies to investigate the presence of this infection in other areas in Brazil. (C) 2011 Elsevier B.V. All rights reserved.