Assessment of extended-spectrum β-lactamase, KPC carbapenemase and porin resistance mechanisms in clinical samples of Klebsiella pneumoniae and Enterobacter spp

The emergence and spread of resistance mechanisms in Gram-negative bacilli has complicated the treatment of serious nosocomial infections. Current automated systems for detection of Klebsiella pneumoniae carbapenemase (KPC)-producing isolates are unreliable. One possible straightforward alternative method is evaluation of ertapenem resistance. However, the accuracy of this method is affected by other resistance mechanisms such as AmpC gene expression or extended-spectrum β-lactamase production associated with porin loss. This study included 128 samples of K. pneumoniae and Enterobacter spp. that were non-susceptible to ertapenem. The disk diffusion and Etest method were applied to determine susceptibility to imipenem, meropenem and ertapenem. Isolates exhibiting intermediate or complete resistance to ertapenem were evaluated for resistance mechanisms. bla(TEM), bla(SHV), bla(CTX-M), bla(CTX-M-2) and bla(KPC) genes were tested for by PCR, and the presence of outer membrane protein was investigated by dot-blot assay. bla(TEM) was detected in 52.9% and 10.3%, bla(SHV) in 29.4% and 0.94%, bla(CTX-M) in 41.4% and 1.9% and bla(CTX-M-2) in 23.5% and 1.9% of K. pneumoniae and Enterobacter cloacae isolates, respectively. The bla(KPC) gene was present in 12.6% of Enterobacter spp. isolates. OmpC and OmpF were present in 6.6% of E. cloacae isolates. These results indicate that several resistance mechanisms contribute to potential therapeutic failure of carbapenem therapy and point to the need for better detection methods and surveillance strategies.

Stem-cell treatment in disc degeneration: What is the evidence?

To review the potential role of stem cells in treating degenerative disc disease of the intervertebral disc (IVD). A review was performed of articles from the Medline database concerning stem cells and degenerative disc disease (DDD). To discuss the data, the papers were classified as: review, in vitro, experimental, and clinical. The currently available treatments were basically for symptom reduction, not to revert the IVD degenerative process. The use of mesenchymal stem cells (MSC) is being proposed as an option of treatment for DDD. In vitro studies have shown that the MSC are able to differentiate into NP cells and that the MSC also reduce the inflammatory levels of the degenerated IVD. Besides, experimental studies demonstrated that the MSC remained viable when injected into the IVD, and that they were able to regenerate partially from the degenerated IVD and its structure. The few clinical studies found in the literature presented diverging results. The use of MSC is being widely studied and shows promising results for the treatment of DDD. Although many advances are being achieved in studies in vitro and experimental, there is a lack of clinical studies to prove the role of MSC in DDD management.

Intra-arterial infusion of autologous bone marrow mononuclear cells in patients with moderate to severe middle cerebral artery acute ischemic stroke

Transplantation of autologous bone marrow mononuclear cells (BMMCs) has been proven safe in animal and human studies. However, there are very few studies in stroke patients. In this study, intra-arterial autologous BMMCs were infused in patients with moderate to severe acute middle cerebral artery infarcts. The subjects of this study included 20 patients with early or late spontaneous recanalization but with persistent deficits, in whom treatment could be initiated between 3 and 7 days after stroke onset. Mononuclear cells were isolated from bone marrow aspirates and infused at the proximal middle cerebral artery of the affected hemisphere. Safety analysis (primary endpoint) during the 6-month follow-up assessed death, any serious clinical events, neurological worsening with ≥ 4-point increase in National Institutes of Health Stroke Scale (NIHSS) scores, seizures, epileptogenic activity on electroencephalogram, and neuroimaging complications including new ischemic, hemorrhagic, or neoplastic lesions. Satisfactory clinical improvement (secondary endpoint) at 90 days was defined according to the pretreatment NIHSS scores as follows: modified Rankin Scale score of 0 in patients with NIHSS <8, modified Rankin Scale scores of 0-1 in patients with NIHSS 8-14, or modified Rankin Scale scores 0-2 in patients with NIHSS >14. Good clinical outcome was defined as mRS ≤2 at 90 days. Serial clinical, laboratory, electroencephalogram, and imaging evaluations showed no procedure-related adverse events. Satisfactory clinical improvement occurred in 6/20 (30%) patients at 90 days. Eight patients (40%) showed a good clinical outcome. Infusion of intra-arterial autologous BMMCs appears to be safe in patients with moderate to severe acute middle cerebral artery strokes. No cases of intrahospital mortality were seen in this pilot trial. Larger prospective randomized trials are warranted to assess the efficacy of this treatment approach.

The dose-response effect of acute intravenous transplantation of human umbilical cord blood cells on brain damage and spatial memory deficits in neonatal hypoxia-ischemia

Despite the beneficial effects of cell-based therapies on brain repair shown in most studies, there has not been a consensus regarding the optimal dose of human umbilical cord blood cells (HUCBC) for neonatal hypoxia-ischemia (HI). In this study, we compared the long-term effects of intravenous administration of HUCBC at three different doses on spatial memory and brain morphological changes after HI in newborn Wistar rats. In addition, we tested whether the transplanted HUCBC migrate to the injured brain after transplantation. Seven-day-old animals underwent right carotid artery occlusion and were exposed to 8% O(2) inhalation for 2 h. After 24 h, randomly selected animals were assigned to four different experimental groups: HI rats administered with vehicle (HI+vehicle), HI rats treated with 1×10(6) (HI+low-dose), 1×10(7) (HI+medium-dose), and 1×10(8) (HI+high-dose) HUCBC into the jugular vein. A control group (sham-operated) was also included in this study. After 8 weeks of transplantation, spatial memory performance was assessed using the Morris water maze (MWM), and subsequently, the animals were euthanized for brain morphological analysis using stereological methods. In addition, we performed immunofluorescence and polymerase chain reaction (PCR) analyses to identify HUCBC in the rat brain 7 days after transplantation. The MWM test showed a significant spatial memory recovery at the highest HUCBC dose compared with HI+vehicle rats (P<0.05). Furthermore, the brain atrophy was also significantly lower in the HI+medium- and high-dose groups compared with the HI+vehicle animals (P<0.01; 0.001, respectively). In addition, HUCBC were demonstrated to be localized in host brains by immunohistochemistry and PCR analyses 7 days after intravenous administration. These results revealed that HUCBC transplantation has the dose-dependent potential to promote robust tissue repair and stable cognitive improvement after HI brain injury.

Use of calcium phosphate cement scaffolds for bone tissue engineering: in vitro study

PURPOSE

To evaluate the ability of macroporous tricalcium phosphate cement (CPC) scaffolds to enable the adhesion, proliferation, and differentiation of mesenchymal stem cells derived from human bone marrow.

METHODS

Cells from the iliac crest of an adult human donor were processed and cultured on macroporous CPC discs. Paraffin spheres sized between 100 and 250µm were used as porogens. Cells were cultured for 5, 10, and 15 days. Next, we assessed cells' behavior and morphology on the biomaterial by scanning electron microscopy. The expression levels of the BGLA and SSP1 genes and the alkaline phosphatase (ALP) activity were quantified by the quantitative real-time polymerase chain reaction technique (QT-PCR) using the fluorophore SYBR GREEN(®).

RESULTS

QT-PCR detected the expression of the BGLA and SSP1 genes and the ALP activity in the periods of 10 and 15 days of culture. Thus, we found out that there was cell proliferation and differentiation in osteogenic cells.

CONCLUSION

Macroporous CPC, with pore sized between 100 and 250µm and developed using paraffin spheres, enables adhesion, proliferation, and differentiation of mesenchymal stem cells in osteogenic cells and can be used as a scaffold for bone tissue engineering.

Bone marrow mononuclear cells reduce seizure frequency and improve cognitive outcome in chronic epileptic rats

AIMS

Epilepsy affects 0.5-1% of the world's population, and approximately a third of these patients are refractory to current medication. Given their ability to proliferate, differentiate and regenerate tissues, stem cells could restore neural circuits lost during the course of the disease and reestablish the physiological excitability of neurons. This study verified the therapeutic potential of bone marrow mononuclear cells (BMMCs) on seizure control and cognitive impairment caused by experimentally induced epilepsy.

MAIN METHODS

Status epilepticus (SE) was induced by lithium-pilocarpine injection and controlled with diazepam 90 min after SE onset. Lithium-pilocarpine-treated rats were intravenously transplanted 22 days after SE with BMMCs obtained from enhanced green fluorescent protein (eGFP) transgenic C57BL/6 mice. Control epileptic animals were given an equivalent volume of saline or fibroblast injections. Animals were video-monitored for the presence of spontaneous recurrent seizures prior to and following the cell administration procedure. In addition, rats underwent cognitive evaluation using a Morris water maze.

KEY FINDINGS

Our data show that BMMCs reduced the frequency of seizures and improved the learning and long-term spatial memory impairments of epileptic rats. EGFP-positive cells were detected in the brains of transplanted animals by PCR analysis.

SIGNIFICANCE

The positive behavioral effects observed in our study indicate that BMMCs could represent a promising therapeutic option in the management of chronic temporal lobe epilepsy.

[Prevalence of metabolic syndrome in indigenous people over 40 years of age in Rio Grande do Sul, Brazil]

OBJECTIVE

To investigate the prevalence of the metabolic syndrome (MS) among indigenous people older than 40 years of age from two cities in the State of Rio Grande do Sul, southern Brazil.

METHODS

A descriptive, analytic, cross-sectional study was conducted in two municipalities, Porto Alegre and Nonoai, between July and August 2009. A total of 150 indigenous people older than 40 years of age (range: 40-104 years), participated in the study. MS prevalence was determined based on National Cholesterol Education Program - Adult Treatment Panel III criteria. Blood samples and anthropometric data were collected. The participants also answered a questionnaire on eating habits, which was then contrasted to the 10 steps to healthy eating proposed by the World Health Organization and recommended by the Brazilian Ministry of Health.

RESULTS

MS prevalence was 65.3%, affecting women more than men (P < 0.001). Changes in waist circumference, fasting glucose, and HDL-cholesterol and presence of hypertension, hypertriglyceridemia, and obesity were associated with MS. Age, smoking, and sedentary lifestyle were not associated with MS. Indigenous people with MS had a poor diet, with low intake of fruit and vegetables, low levels of physical activity, high consumption of sweets and soft drinks, and high prevalence of obesity.

CONCLUSIONS

A high prevalence of MS was observed among the indigenous people surveyed, especially in women. Education and motivation for healthy behaviors is possibly the best way to manage MS and promote health in a population that is still neglected by public health policies.

Association between T102C polymorphism of serotonin 2A receptor gene and urinary incontinence in older women

BACKGROUND

The bladder's regulatory function is influenced by central serotonergic modulation. T102C polymorphism of the serotonin 2A (5-HT(2A)) receptor gene is associated with urinary incontinence (UI) that has been reported by older community dwellers. We analyzed the association between 5-HT(2A) receptor gene polymorphism and urodynamic tests for UI in older women.

METHODS

A case-control study was performed with 68 older women submitted to urodynamic evaluation and 162 older women without urinary problems (self-reported), all community dwellers enrolled in the Gravataí-GENESIS Project, Brazil. Clinical interviews, complete urodynamic evaluation following the International Continence Society Report on Good Urodynamic Practice (case group), and molecular analyses were performed (case and control groups). Serotonin 2A receptor gene genotyping was carried out by polymerase chain reaction-restriction fragment length polymorphism using the restriction enzyme HpaII. We excluded patients with diabetes mellitus, neurologic damage, and diuretic intake.

RESULTS

The subjects' mean (SD) age was 68.1 (6.5) years (range, 60-92 years). We found an association between the TT genotype versus CC + CT genotypes and UI (P = 0.013; odds ratio, 2.69; 95% confidence interval, 1.37-5.29) and, in addition, an association with urgency UI, maximal cystometric capacity (TT, 349 mL; CC + CT, 429.5 mL [P = 0.047]), detrusor pressure at maximum cystometric capacity (TT, 11 cm H(2)O; CC + CT, 6.75 cm H(2)O [P = 0.032]), and detrusor compliance (TT, 34 mL/cm H(2)O; CC + CT, 61.25 mL/cm H(2)O [P = 0.006]).

CONCLUSIONS

We confirmed our previous findings of a genetic influence of the TT genotype on UI involving the serotonergic pathway among older women. Further investigations including 5-HT(2A) expression in the bladder, pelvic floor, and striated sphincter muscle must be performed.

Effect of titanium surface roughness on human bone marrow cell proliferation and differentiation: an experimental study

PURPOSE

To assess the proliferation and differentiation of human bone marrow-derived cells cultured on titanium surfaces with different roughness characteristics.

METHODS

Cells obtained from the iliac crest of an adult human donor were routinely processed and cultured on titanium surfaces of varying roughness, according to their preparation method: polishing only (smooth surface) and polishing followed by etching with HF/HNO3 for 15 and 30 minutes (rough surfaces). Surfaces were assessed using scanning electronic microscopy and profilometry.

RESULTS

Titanium disks etched with acid for 15 minutes allowed greater cell proliferation in all culture periods. The level of osteopontin and osteocalcin expression was increased in both acid-etched groups, which indicates an advanced stage of differentiation of cells into osteoblasts.

CONCLUSIONS

Increased surface roughness accelerates the differentiation of undifferentiated mesenchymal cells into osteogenic lineage cells, but does not necessarily favor cell proliferation. An intermediate surface roughness of 0.5microm (acid etching for 15 minutes) favors both initial and final cell responses.

Effects of human aging on periodontal tissues

Loss of teeth is frequently associated with periodontal disease in older adults. The aim of this review was to present the effects of aging on the periodontal tissues. Aging alone does not lead to critical loss of periodontal attachment in healthy elderly persons. The effects of aging on periodontal tissues are based on molecular changes in the periodontal cells, which intensify bone loss in elderly patients with periodontitis. These effects may be associated with (1) alterations in differentiation and proliferation of osteoblasts and osteoclasts; (2) an increase in periodontal cell response to the oral microbiota and mechanical stress leading to the secretion of cytokines involved in osseous resorption; and (3) systemic endocrine alterations in the elderly people.

Differentiation of human adipose-derived adult stem cells into neuronal tissue: does it work?

Adipose tissue contains many cells and proteins that are of value not only for their potential therapeutic applications, but also for the low cost of their harvest and delivery. Mesenchymal stem cells (MSC) were originally isolated from the bone marrow, although similar populations have been isolated from adipose and other tissues. At one time, neural tissues were not regarded as regenerative populations of cells. Therefore, the identification of cell populations capable of neuronal differentiation has generated immense interest. Adipose tissue may represent an alternative source of cells that are capable of neuronal differentiation, potentially enhancing its use in the treatment of neurological disease. The aim of this review is to cover the current state of knowledge of the differentiation potential of human adipose-derived stem (ADAS) cells, specifically their ability to give rise to neuronal cells in vitro. This review presents and discusses different protocols used for inducing human ADAS cells to differentiate in vitro, and the neuronal markers utilized in each system.

Can local supply of bone marrow mononuclear cells improve the outcome from late tubular repair of human median and ulnar nerves?

The purpose of this non-randomised retrospective study was to compare nerve regeneration after reconnection with silicone tubes with two different strategies. A total of 44 patients with injured median or ulnar nerves in the forearm were surgically treated. In one group of patients, a silicone tube alone was placed in the nerve gap. In a second group, the silicone tube was filled with autologous bone marrow mononuclear cells obtained by aspiration from the iliac crest. Motor function, sensation and the effect of pain on function were assessed 1 year after surgery. The tubes filled with bone marrow cells showed better recovery than the empty tubes. The use of bone marrow mononuclear cells in addition to tube re-connection may promote better nerve regeneration than conventional tubular repair.

TNF-a and IL-10 levels in tracheobronchial lavage of ventilated preterm infants and subsequent lung function

The role of airway inflammation in ventilated preterm newborns and the risk factors associated with the development of chronic lung disease are not well understood. Our objective was to analyze the association of the airway inflammatory response in ventilated preterm infants by serial measurements of TNF-alpha and IL-10 in tracheobronchial lavage (TBL) with perinatal factors and lung function measured early in life. A series of TBL samples were collected from ventilated preterm infants (less than 32 weeks of gestational age) and concentrations of TNF-alpha and IL-10 were measured by ELISA. Pulmonary function tests were performed after discharge by the raised volume rapid compression technique. Twenty-five subjects were recruited and 70 TBL samples were obtained. There was a significant positive association between TNF-alpha and IL-10 levels and length of time between the rupture of the amniotic membranes and delivery (r = 0.65, P = 0.002, and r = 0.57, P < 0.001, respectively). Lung function was measured between 1 and 22 weeks of corrected age in 10 patients. Multivariable analysis with adjustment for differences in lung volume showed a significant negative association between TNF-alpha levels and forced expiratory flow (FEF(50); r = -0.6; P = 0.04), FEF(75) (r = -0.76; P = 0.02), FEF(85) (r = -0.75; P = 0.03), FEF(25-75) (-0.71; P = 0.02), and FEV(0.5) (r = -0.39; P = 0.03). These data suggest that TNF-alpha levels in the airways during the first days of life were associated with subsequent lung function abnormalities measured weeks or months later.

Cyclin D1 expression and cervical metastases in squamous cell carcinoma of the mouth

Summary

Cervical metastasis represent the most relevant prognostic factor in carcinomas of the mouth. Clinical and histological factors are associated with the development of cervical metastasis; however, research on molecular factors has been broadly carried out in recent years.

Aim

The aim of this study is to analyze the association of the Cyclin D1 as a risk factor for the presence of cervical metastasis.

Materials and Methods

Cyclin D1 expression was measured and the association between such substance and metastasis was found in 45 patients with mouth cancer treated by the author of this paper. Cyclin D1 presence was checked through the stereological method. Clinical and histological characteristics have been analyzed and associated with metastasis.

Results

Cyclin D1 expression was found in 15 patients but it was not associated with clinical and histological factors related to the presence of metastasis. Such conclusion indicates that Cyclin D1 is an independent protein. The most important predictive aspects related to metastasis development have been clinical staging and vascular embolization.

Conslusions

Cyclin D1, although independent, is not associated with cervical metastasis, while staging and vascular embolization are.

Modelo experimental de lesão raquimedular em ratos com dispositivo para acesso de agentes terapêuticos locais

Um modelo experimental de lesão raquimedular com localização precisa e reproduzível é uma ferramenta extremamente importante para o estudo de novas terapias em lesões raquimedulares. OBJETIVOS: Desenvolver um modelo experimental de lesão raquimedular em ratos que produza lesão completa (paraplegia) com o posicionamento de um sistema que permita o acesso de agentes próximo ao local da lesão para testar agentes terapêuticos locais. MÉTODOS: Quinze ratos Wistar foram submetidos à transecção cirúrgica da medula espinhal, realizada com o uso de tesoura ao nível dos corpos vertebrais de T-13 a L-3 e, ao final do procedimento, à implantação de um cateter subcutâneo para o acesso de agentes terapêuticos locais ao local da lesão. RESULTADOS: Um modelo experimental de paraplegia foi consistentemente desenvolvido com a adição suplementar de um cateter para o acesso de agentes terapêuticos locais ao local da lesão. CONCLUSÃO: Um modelo animal de lesão raquimedular e um sistema para o acesso de agentes terapêuticos locais pode ser reproduzido para o estudo de diferentes modificadores da resposta regenerativa em um modelo de ratos com lesão raquimedular.

Evaluation of the humoral immune response in BALB/c mice immunized with a naked DNA vaccine anti-methicillin-resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is the major pathogen involved in nosocomial infections, leading to high rates of morbidity and mortality in hospitals worldwide. The methicillin resistance occurs due to the presence of an additional penicillin-binding protein, PBP2a, which has low affinity for beta-lactam antibiotics. In the past few years, vancomycin has been the only antibiotic option for treatment of infections caused by multiresistant MRSA; however, reports of vancomycin-resistant strains have generated great concerns regarding the treatment to overcome these infections. In the present study, we report preliminary results regarding the humoral immune response generated in BALB/c mice by two different doses of naked DNA vaccine containing an internal region, comprising the serine-protease domain, of the PBP2a of MRSA. The immunization procedure consisted of four immunizations given intramuscularly within 15-day intervals. Blood was collect weekly and anti-PBP2a-specific antibodies were screened by ELISA. BALB/c mice immunized with DNA vaccine anti-PBP2a have shown higher antibody titers mainly after the fourth immunization, and intriguingly, no correlation between the humoral immune response and DNA dose was observed. Our results suggest that the DNA vaccine anti-PBP2a induced an immune response by production of specific antibodies anti-MRSA in a non-dose-dependent manner, and it could represent a new and valuable approach to produce specific antibodies for passive immunization to overcome MRSA infections.

Efeitos das células tronco adultas de medula óssea e do plasma rico em plaquetas na regeneração e recuperação funcional nervosa em um modelo de defeito agudo em nervo perfiférico em rato

OBJETIVOS: Foram avaliados os efeitos do uso de células tronco da medula óssea (CTM) e do plasma rico em plaquetas (PRP) na regeneração de nervos periféricos, utilizando um modelo estabelecido de regeneração de nervo ciático em ratos. MÉTODOS: Um defeito nervoso de 10 mm foi reconstruído com a utilização de um tubo de silicone preenchido com CTM, PRP ou ambos. O grupo controle recebeu somente o tubo de silicone. Foi realizado ainda um quinto grupo no qual o intervalo foi reconstruído utilizando o segmento ressecado do nervo. A função motora foi testada seis semanas após a cirurgia utilizando teste de marcha. Após o teste motor, os ratos foram anestesiados, o nervo ciático e o tubo foram ressecados e foi realizada microscopia eletrônica de transmissão. RESULTADOS: A análise quantitativa demonstra uma melhora na recuperação funcional no grupo CTM em comparação com os demais grupos. Regeneração nervosa foi demonstrada no grupo CTM por microscopia eletrônica de trasmissão com uma recuperação praticamente completa da anatomia neural. CONCLUSÃO: Nossos resultados sugerem que o uso de CTM associado com a técnica de tubulização promove uma satisfatória recuperação da função motora e regeneração nervosa.

Viral coinfection in the oral cavity of HIV-infected children: relation among HIV viral load, CD4+T lymphocyte count and detection of EBV, CMV and HSV

Viral coinfection in the oral cavity associated to HIV infection was evaluated in 180 children from birth to 13 years of age of both sexes. The oral examinations were performed at the Pediatric AIDS Outpatient Clinic, São Lucas Hospital and Clinic Hospital, both in Porto Alegre, Brazil and at the School of Dental Medicine, University Hospital Center, State University of New York at Stony Brook, USA. The aim of this study was to identify the presence of viral infections in the oral cavity. PCR technique was used to determine opportunistic viral infections caused by CMV, EBV, and HSV in mucosal swabs. A high frequency of viral infection was detected in the oral cavity of HIV-infected children determined by the PCR technique. HIV-infected children with viruses had a favorable CD4+T lymphocyte count and unfavorable viral load.

Th-1 and Th-2 cytokine production in infants with virus-associated wheezing

Wheezing associated with respiratory viral infections in infancy is very common and results in high morbidity worldwide. The Th1/Th2 pattern of immune response in these patients remains unclear and previous studies have shown controversial results. The aim of the present study was to compare the type of Th1/Th2 cytokine response between infants with acute bronchiolitis, recurrent wheezing and upper respiratory infections from a developing country. Infants younger than 2 years of age admitted to Hospital São Lucas, Porto Alegre, RS, Brazil, between May and November 2001, with an acute episode of wheezing associated with viral respiratory infection were selected. Subjects with upper respiratory infections from the emergency department were selected for the control group. Interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) levels from nasal aspirates were determined by ELISA from peripheral mononuclear cell cultures. Twenty-nine subjects with acute bronchiolitis, 18 with recurrent wheezing and 15 with upper respiratory infections were enrolled. There were no differences in family history of atopy or parental smoking between groups. Oxygen requirement was similar for the acute bronchiolitis and recurrent wheezing groups. The percentage of positive tests for the cytokines studied and the IFN-gamma/IL-4 ratio was similar for all groups. Comparison of the polarized Th1/Th2 cytokine results for the various groups showed no specific pattern of cytokine production. Infants with wheezing from a developing country do not show any specific predominant pattern of Th1/Th2 cytokine production, suggesting that multiple factors may be involved in the pathogenesis of this illness.

Infection of BALB/c mice with Angiostrongylus costaricensis decreases pulmonary inflammatory response to ovalbumin

SUMMARY The prevalence of asthma in developing countries is lower than in developed countries. Viral, bacterial and parasitic infections may be associated with this discrepancy. The relationship between parasitic infection and asthma prevalence is not clear. Previous controversial data have demonstrated that parasitic infection may either predispose or protect against the development of asthma. The aim of this study is to determine whether infection with Angiostrongylus costaricensis (A. costaricensis) decreases inflammatory lung response to ovalbumin (OVA) in mice. Seven BALB/c mice were infected with A. costaricensis by orogastric gavage (10 larvae/mouse) on day (D) 0. The mice were immunized against OVA by intraperitoneal injection on D 5 and D 12 and received an intranasal OVA challenge (40 micro L) on D 15 and D 17. On D 19 bronchoalveolar lavage (BAL) was performed. Six BALB/c mice (control group) were immunized with OVA using the same protocol, but were not infected with A. costaricensis. Interleukin (IL)-1beta and IL-6 levels were measured in the BAL fluid by using commercial ELISA assays. Total cell counts and differential cell counts were performed in the BAL fluid samples. The group infected with A. costaricensis had lower total cell count in the BAL fluid when compared with the control group (0.11 x 10(6)cells/mL and 0.3 x 10(6)cells/mL, respectively; P = 0.013). BAL fluid IL-1beta levels in the infected group were significantly lower than in the control group (P = 0.008). IL-6 levels in BAL fluid were not different between the groups studied. We conclude that Angiostrongylus costaricensis infection in mice decreases pulmonary inflammatory response to OVA.

Discrepancy between cytokine production from peripheral blood mononuclear cells and nasal secretions among infants with acute bronchiolitis

BACKGROUND

Many studies have measured cytokine production derived from peripheral blood mononuclear cells (PBMCs) to evaluate the immune response in acute bronchiolitis (AB), but no previous reports have examined the association between PBMC release of cytokines and concomitant airway immune response.

OBJECTIVE

To determine whether interferon-gamma (IFN-gamma), interleukin 4 (IL-4), and IL-10 levels from PBMCs are associated with concurrent cytokine release in the airways of infants with AB.

METHODS

Infants with acute viral-associated first episode of wheezing who required hospitalization between May and September 2002 were recruited. Nasopharyngeal aspirates (NPAs) and PBMC samples were collected simultaneously. The concentrations of IFN-gamma, IL-4, and IL-10 in NPA and PBMC supernatants were determined by enzyme-linked immunosorbent assay.

RESULTS

Twenty infants with AB were enrolled in the study of whom 17 (85%) had positive NPA immunofluorescence results for viral detection and respiratory syncytial virus. Median total cell count and viability from NPA samples were 2.2 x 10(6) cells/mL (SD, 1.7 cells/mL) and 92% (SD, 6.0%), respectively. There was a significant correlation between IL-4 levels from NPA and PBMC samples (r = 0.5, P = .02); however, we did not find an association between IFN-gamma and IL-10 levels.

CONCLUSIONS

Cytokines produced by in vitro PBMCs may not necessarily reflect the concurrent cytokine pattern production at the mucosal surface in the respiratory tract of infants with AB. Further studies are required to determine whether peripheral blood is a reliable sample for airway inflammation evaluation and to explain the discrepancies of cytokine productions found in this study.

Effect of clarithromycin on the cell profile of bronchoalveolar lavage fluid in mice with neutrophil-predominant lung disease

OBJECTIVE

Macrolide antibiotics have anti-inflammatory properties in lung diseases. The aim of this study was to investigate the effect of clarithromycin in pulmonary cellular inflammatory response in mice.

METHOD

Eight adult Swiss mice were studied. All animals received an intranasal challenge (80 micro L) with dead Pseudomonas aeruginosa (1.0 x 10(12) CFU/mL). Bronchoalveolar lavage was performed 2 days later, with total cell count and differential cell analysis. The study group (n = 4) received clarithromycin treatment (50 mg/kg/day, intraperitoneal) for 5 days. Treatment was initiated 2 days before intranasal challenge.

RESULTS

There was no significant difference in total cell count between the groups (mean: 2.0 x 10(6) and 1.3 x 10(6), respectively). In both groups, there was a predominance of neutrophils. However, the study group had a higher percentage of lymphocytes in the bronchoalveolar lavage than the control group (median of 19% vs 2.5%, P =.029).

CONCLUSION

Clarithromycin alters the cytological pattern of bronchoalveolar lavage of Swiss mice with neutrophil pulmonary inflammation, significantly increasing the percentage of lymphocytes.

Modified location of the major histocompatibility protein Kb by co-delivery with VP22 protein

We report the construction of an expression vector pVP22::Kb that encodes a chimeric protein composed of VP22 and murine major histocompatibility complex class I molecule, Kb. Flow cytometry assays show that VP22 modifies normal cell surface localization of Kb protein.