Safety of specific immunotherapy using a depigmented and polymerised extract of Dermatophagoides pteronyssinus in children under five years of age

BACKGROUND

Different opinion documents point to a patient age of under five years as a relative contraindication to specific immunotherapy, arguing that this age group has a greater risk of developing anaphylaxis, and that specially trained personnel are needed to deal with the problem if it occurs. However, insufficient evidence exists to support such an affirmation.

PATIENTS AND METHODS

A retrospective follow-up observational study was made of patients aged 60 months or younger who had been subjected to specific immunotherapy. We included 77 children with a diagnosis of extrinsic bronchial asthma (n=68), extrinsic spasmodic cough (n=5) and allergic rhinitis (n=4) confirmed by clinical criteria and prick-test, with specific IgE positivity to Dermatophagoides pteronyssinus. All patients received specific immunotherapy with an extract of depigmented D. pteronyssinus polymerised with glutaraldehyde, involving an initial cluster protocol of two weeks and monthly maintenance doses. All observed adverse reactions were recorded, and classified according to European Academy of Allergy and Clinical Immunology (EAACI) criteria.

RESULTS

A total of 1837 doses were administered to the 77 patients, with four adverse reactions being observed in three patients. Three reactions (0.16% of the administered doses) were local and immediate, while one was systemic and of grade 2 (0.05% of the administered doses) - consisting of an episode of nocturnal wheezing.

CONCLUSIONS

Specific immunotherapy in children under five years of age with the extract used is safe. We consider that further studies are needed, involving other types of extracts, to allow reconsideration of the relative contraindication of patient age for the administration of immunotherapy.

Success of medical therapy in a rare case of cecal ameboma

Colitis caused by Entamoeba histolytica (EH) is prevalent in developing countries. Clinical presentation ranges from mild diarrhoea episodes to dysentery and liver abscess. Ameboma, a complication caused by EH invasion of the intestinal wall, is a rare presentation of amebiasis, occurring approximately in 1.5% of cases. Because of its insidious and variable clinical presentation only few cases are diagnosed previous to surgical intervention. We report a 52 years old Mexican-mestizo female, presenting with a pain-less right lower quadrant abdominal mass and diagnosed of cecal ameboma prior to surgery by colonoscopy and histopathologic examination. The present case highlights the importance of early diagnosis and medical therapy with antiparasitic drugs in order to avoid complications that could lead these patients to unnecessary surgical management.

Prognostic factors and predictors of in-hospital mortality of patients with heart failure with preserved left ventricular ejection fraction

BACKGROUND AND AIM

To date, in-hospital mortality predictors of patients with heart failure and depressed left ventricular ejection fraction are well known. Nevertheless, this is not the case of patients suffering from heart failure with preserved left ventricular ejection fraction. Our aim is to describe the incidence and predictors of in-hospital mortality in patients during the first admission due to preserved left ventricular ejection fraction.

METHODS

Seven hundred and seventy-one consecutive patients with a first admission to hospital due to preserved left ventricular ejection fraction between January 2002 and September 2003 comprised our study group. Cardiovascular risk factors, clinical, electrical and echocardiographic variables were studied. Univariate and multivariate logistic regression analysis was performed to obtain those factors independently associated with in-hospital mortality.

RESULTS

The mean age was 82.6 +/- 43.6 years (551 women, 66.3%). Variables in both groups were similar except for the history of ischaemic heart disease, dilated cardiomyopathy and the presence of normal sinus rhythm. Multivariate logistic regression analysis showed that a history of ischaemic heart disease, dilated cardiomyopathy and a cardiac rhythm different from normal sinus rhythm are associated with an increased in-hospital mortality.

CONCLUSION

Patients with preserved left ventricular ejection fraction have high in-hospital mortality during the first admission. A history of ischaemic heart disease, a history of dilated cardiomyopathy and the presence of a cardiac rhythm different from the normal sinus rhythm (atrial fibrillation or flutter or paced rhythm) are independent predictors of in-hospital mortality in these patients. These factors must especially be considered during the admission of such patients.

Genotoxic and cytotoxic studies of beta-sitosterol and pteropodine in mouse

Beta-sitosterol (BS) and pteropodine (PT) are constituents of various plants with pharmacological activities potentially useful to man. The chemicals themselves possess biomedical properties related to the modulation of the immune and the nervous systems, as well as to the inflammatory process. Therefore, safety evaluation of the compounds is necessary in regard to their probable beneficial use in human health. The present study evaluates their genotoxic and cytotoxic potential by determining the capacity of the compounds to induce sister chromatid exchanges (SCE), or to alter cellular proliferation kinetics (CPK) and the mitotic index (MI) in mouse bone marrow cells. Besides, it also determines their capacity to increase the rate of micronucleated polychromatic erythrocytes (MNPE) in peripheral mouse blood, and the relationship polychromatic erythrocytes/normochromatic erythrocytes (PE/NE) as an index of cytotoxicity. For the first assay, four doses of each compound were tested: 200, 400, 600, and 1000 mg/kg in case of BS, and 100, 200, 300, and 600 mg/kg for PT. The results in regard to both agents showed no SCE increase induced by any of the tested doses, as well as no alteration in the CPK, or in the MI. With respect to the second assay, the results obtained with the two agents were also negative for both the MNPE and the PE/NE index along the daily evaluation made for four days. In the present study, the highest tested dose corresponded to 80% of the LD₅₀ obtained for BS and to 78% in the case of PT. The results obtained establish that the studied agents have neither genotoxic nor cytotoxic effect on the model used, and therefore they encourage studies on their pharmacological properties.

Molecular heterogeneity in chronic lymphocytic leukemia is dependent on BCR signaling: clinical correlation

Chronic lymphocytic leukemia (CLL), the most frequent form of adult leukemia in Western countries, is characterized by a highly variable clinical course. Expression profiling of a series of 160 CLL patients allowed interrogating the genes presumably playing a role in pathogenesis, relating the expression of functionally relevant signatures with the time to treatment. First, we identified genes relevant to the biology and prognosis of CLL to build a CLL disease-specific oligonucleotide microarray. Second, we hybridized a training series on the CLL-specific chip, generating a biology-based predictive model. Finally, this model was validated in a new CLL series. Clinical variability in CLL is related with the expression of two gene clusters, associated with B-cell receptor (BCR) signaling and mitogen-activated protein kinase (MAPK) activation, including nuclear factor-kappaB1 (NF-kappaB1). The expression of these clusters identifies three risk-score groups with treatment-free survival probabilities at 5 years of 83, 50 and 17%. This molecular predictor can be applied to early clinical stages of CLL. This signature is related to immunoglobulin variable region somatic hypermutation and surrogate markers. There is a molecular heterogeneity in CLL, dependent on the expression of genes defining BCR and MAPK/NF-kappaB clusters, which can be used to predict time to treatment in early clinical stages.

[Specialized care program for end-stage heart failure patients. Initial experience in a heart failure unit]

INTRODUCTION AND OBJECTIVES

End-stage heart failure is associated with very high morbidity and mortality. Palliative care has been little studied in affected patients.

PATIENTS AND METHOD

Between January 1998 and December 2004, 61 patients with end-stage heart failure participated in a specialized advanced heart failure care program. The program included patient education on advanced heart failure, with day-care and home-care elements, and involved intravenous drug administration when necessary.

RESULTS

The mean age of the study population was 64 (13) years (range 32-87 years), with 92% being male. Their mean ejection fraction was 23 (6%), mean systolic blood pressure 100 (16) mm Hg, mean blood sodium level 137 (4) mEq, mean creatinine level 1.7 (0.8) mg/dL, and mean hemoglobin level 12 (2) mg/dL. The number of hospitalizations, number of days in hospital per admission, and number of emergency room visits in the year before inclusion in the specialized heart failure care program were 5.7 (0.5), 53 (5), and 8.3 (1.1), respectively. After inclusion, these figures decreased significantly to 1.9 (0.2) (P=.0001), 19 (3) (P=.0001), and 1.2 (0.2) (P=.0001), respectively. During a mean follow-up period of 11 (10) months, 28 patients died (47%) and 23 (38%) underwent heart transplantation. In addition, use of the program led to a reduction in healthcare costs.

CONCLUSIONS

Although mortality in end-stage heart failure patients remained very high, use of a specialized advanced heart failure care program decreased the number of hospitalizations, days per hospitalization, and emergency room visits, and reduced the cost of care.

Skeletal muscle inflammation and nitric oxide in patients with COPD

In chronic obstructive pulmonary disease (COPD) the presence of systemic inflammation has been associated with peripheral muscle abnormalities and weight loss. To study whether inflammatory factors are important in these processes, the present study compared the skeletal muscle levels of nitrite, nitrate, nitrotyrosine, neuronal, endothelial and inducible nitric oxide synthases (nNOS, eNOS, and iNOS, respectively), and inflammatory markers (tumour necrosis factor (TNF)-alpha, CD154 and CD163) in 15 patients (forced expiratory volume in one second 43+/-11%) and 14 controls. All these markers were also compared between patients with normal and low body weight. Nitrite (12.5+/-2.6 versus 17.0+/-3.4 micromol.mg(-1) protein), nitrate (20.7+/-2.4 versus 24.4+/-4.5 micromol.mg(-1) protein) and eNOS (31.9+/-4.6 versus 43.6+/-7.5 ng.mg(-1) protein) were lower in COPD patients than in controls. Nitrotyrosine (25.6+/-5.4 versus 6.6+/-3.3 ng.mg(-1) protein), iNOS expression (32+/-9.5 versus 7.16+/-2.7 ng.mg(-1) protein), TNF-alpha (257+/-160 versus 48.3+/-4.4 pg.mg(-1) protein) and CD163 (6.4+/-2.1 versus 0.8+/-0.4 ng.mg(-1) protein) were higher in COPD patients than in controls. CD154 levels were 15.7+/-7.0 ng.mg(-1) protein in COPD patients and undetectable in controls. Similar levels of all these markers were observed in COPD patients with normal and low body weight. In conclusion, these findings suggest the presence of an inflammatory process in the muscle tissue of chronic obstructive pulmonary disease patients, and argue in favour of its participation in the pathogenesis of skeletal muscle abnormalities.

Changes in Exercise Tolerance, Health Related Quality of Life, and Peripheral Muscle Characteristics of Chronic Obstructive Pulmonary Disease Patients After 6 Weeks' Training

OBJECTIVE

This study was designed to assess changes in skeletal muscle characteristics after 6 weeks' high-intensity physical training of patients with moderate to severe chronic obstructive pulmonary disease (COPD) and to determine how the changes were related to improvements in exercise tolerance and health related quality of life (HRQL).

PATIENTS AND METHODS

Ten patients with a mean (SD) age of 60 (10) years and a forced expiratory volume in 1 second of 32% (9%) were enrolled. The effect of training on the 6-minute walk test, HRQL questionnaires, and skeletal muscles was examined for the 8 patients who completed the program. The structural and chemical characteristics of skeletal muscles before and after training were studied in vastus lateralis muscle biopsies.

RESULTS

Training significantly modified the 6-minute walk test (P<.01), HRQL (P<.05), and citrate synthetase activity (P<.05). Changes in distances walked during the 6-minute walk test were significantly related to changes in the mean area of fibers (r=0.81).

CONCLUSIONS

The results of this study indicate that 6 weeks of high-intensity physical training of COPD patients produces moderate changes in skeletal muscles which could partly explain improvements observed in exercise tolerance after respiratory rehabilitation.

Inflammation and nitric oxide production in skeletal muscle of type 2 diabetic patients

An inflammatory process may be involved in nitric oxide production in skeletal muscle of type 2 diabetic patients. Nitric oxide generation in skeletal muscle was assessed in 14 non-complicated type 2 diabetic patients and in 12 healthy subjects. In samples of quadriceps femoris muscle, endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), nitrite, nitrate and nitrotyrosine were determined. The macrophage-specific antigen CD163, the T-cell membrane factor CD154 and tumour necrosis factor-alpha (TNF-alpha) were also assayed. In six patients, ultrastructural analysis of muscle was performed. Nitrites and nitrates were increased in patients as compared to controls (22.7+/-4.5 and 32.7+/-7.0 vs 16.0+/-2.9 and 22.8+/-4.0 micromol/mg protein; P<0.001, Mann-Whitney U test). Endothelial NOS was similar in diabetic and control subjects (36.4+/-13.8 vs 36.3+/-6.8 ng/mg protein), contrasting with the significant increase of iNOS recorded in patients (34.3+/-13.0 vs 8.5+/-2.8 ng/mg protein, P<0.00002). Nitrotyrosine levels were higher in the patient than in the control group (42.1+/-24.4 vs 10.3+/-2.5 ng/mg protein, P<0.00002), as were CD163 (10-fold) and TNF-alpha (fourfold) levels. Furthermore, CD154 levels were detectable only in the patient samples (10.2+/-5.3 ng/mg protein). By multiple-regression analysis, changes in glycated haemoglobin values could predict 96% variation in nitrotyrosine. Macrophages were present in all muscle samples analysed by electromicroscopy. The increased levels of CD163, CD154 and TNF-alpha indicate that an inflammatory process occurs in skeletal muscle of type 2 diabetic patients. This may contribute to iNOS induction, muscle damage and insulin resistance.

Glutathione and glutamate levels in the diaphragm of patients with chronic obstructive pulmonary disease

Recently, decreased glutamate (Glu) and reduced glutathione (GSH) levels were reported in the quadriceps femoris of patients with chronic obstructive pulmonary disease (COPD). The aim of the present study was to investigate whether Glu and GSH levels are also modified in the diaphragm of these patients. Nine male COPD patients (forced expiratory volume in one second (FEV1) range 28-68% of the predicted value) and seven male patients with normal pulmonary function (mean +/- SD FEV1 86 +/- 3% pred) submitted to thoracotomy were included. Biopsy specimens were taken from the diaphragm (both groups) and the quadriceps femoris (COPD group alone) in order to assess fibre size, myosin heavy chain expression, GSH levels and amino acid profile. The COPD group was characterised by preserved fibre size, a higher proportion of type I fibres (mean +/- SEM 70 +/- 3 versus 26 +/- 4%), and higher Glu and GSH content in the diaphragm compared to the quadriceps muscle. However, Glu and GSH levels were similar in diaphragm from the COPD and control groups. Glu level correlated with GSH level in both muscles. No significant correlation was found between Glu or GSH level and fibre size or proportions. This study shows that glutamate and reduced glutathione levels are preserved in the diaphragm of chronic obstructive pulmonary disease patients. Alterations in glutamate and reduced glutathione metabolism are muscle-specific in chronic obstructive pulmonary disease, affecting the quadriceps femoris but not the diaphragm. Glutamate and reduced glutathione levels are strongly interrelated in both muscles, independent of fibre type distribution and fibre size.

Development and validation of an enzyme-linked immunosorbent assay (ELISA) for recombinant human gamma interferon

A one-site ELISA for the quantification of recombinant human gamma interferon (rh-IFN-gamma) was developed and validated. A single monoclonal antibody (Mab) was used as a "catching" antibody and as a horseradish peroxidase (HRP)-labeled conjugate. Detection limit and quantification limit of this assay were estimated to be 1.26 and 15 ng/mL, respectively, and the coefficient of variation was below 15%. The ELISA was specific for rh-IFN-gamma, showing no cross reactivity to other related molecules in the range of the concentrations studied. The results correlated well with those obtained by a bioassay method. By using this assay, it was demonstrated that 0.01-1% (v/v) Tween 80 protected rh-IFN-gamma during freezing and thawing.

Dual morphometrical changes of the deltoid muscle in patients with COPD

The present study was specifically aimed at evaluating if the structure of the deltoid muscles is modified in patients with chronic obstructive pulmonary disease (COPD). Twenty-eight male volunteers (61+/-13 yr) were assigned, according to pulmonary function, to either the COPD (n=14, FEV(1)=22-74%pred) or control group (n=14, FEV(1)=83-121%pred). Biopsies from non-dominant deltoid muscle were obtained and processed for morphometric analysis of the fibre types. Both type I and type II muscle fibres were distributed in the typical mosaic pattern. The mean value of the fibre size was within the normal range. However, three differentiated modes were observed in the deltoid from COPD patients: a central mode of normal sized fibres, a mode of atrophic fibres and a mode of hypertrophic fibres. This observation was evident even within single fascicles and especially prevalent in the most severe COPD patients. We conclude that factors with opposite effect (promotion of either atrophy or hypertrophy) exert relevant roles in the histomorphometrical characteristics of the deltoid muscles in COPD patients.

Metabolic changes in DOCA-salt hypertensive rats

In a previous report, we observed an altered proportion of fiber types and a reduction of capillary per fiber ratio in extensor digitorus longus (EDL) and soleus (SOL) muscles of deoxicorticosterone acetate (DOCA)-salt hypertensive rats when compared with controls. The aim of the present study was to ascertain various carbohydrate and lipid enzyme activities and substrates that may be involved in the morphological changes reported. In the SOL muscle of hypertensive rats, glucose, glycogen and triglycerides (TG) levels were increased, citrate synthase (CS) and beta-hydroxy-acyl-CoA dehydrogenase (HAD) activities were reduced, while hexokinase (HK) and lipoprotein lipase (LPL), LPL mass, lactate and free fatty acids (FFA) levels were unchanged. In EDL muscles of hypertensive rats, glycogen levels and LPL mass were higher than in controls, while CS, HAD, HK, and LPL activities and glucose, lactate, FFA and TG levels were unmodified. Serum levels of insulin, TG, cholesterol and FFA were increased while glucose levels were decreased and high-density lipoprotein-cholesterol levels were similar in hypertensive rats when compared with controls. In conclusion, hypertensive rats showed increased glycogen in both EDL and SOL muscles, with hyperinsulinemia and reduced glycemia. Hyperinsulinemia might have been a compensatory response to insulin resistance. The oxidative capacity of SOL muscle was reduced indicating that glucose uptake was conduced via non-oxidative metabolism. TG, FFA and cholesterol were increased in serum and TG in SOL muscle.

[Basic structure of respiratory and peripheral muscles in the beagle dog]

BACKGROUND

The dog is one of the most widely used animals in studies of respiratory physiopathology, mainly because of its physiological characteristics. However, ethical and legal constraints are placed on the use of some species in our context.

OBJECTIVE

We studied the underlying structural features of respiratory and peripheral muscles in the beagle dog in order to suggest reference values for future studies.

METHOD

Fourteen young beagles were selected. Samples were taken from the costal diaphragm (DFG), external intercostal (EI) and vastus medialis (VM) muscles. We analyzed fiber percentages and sizes (immunohistochemistry, using myosin heavy chain [MyHC (monoclonal antibodies), percentages and absolute number of MyHC isoforms (electrophoresis and ELISA), and level of membrane damage (immunohistochemistry, using anti-fibronectin monoclonal antibodies).

RESULTS

In the EI muscle, type I fibers were larger (by 20%) than type II fibers. Fibers resistant to fatigue (type I) predominated greatly over fast contraction fibers (type II) in all three muscles analyzed (DFG 57% 11% vs. 45% 12%; EI 58% 5% vs. 43% 5%; and VM 70% 8% vs. 34% 7 %). Few hybrid fibers (co-expression of fast and slow MyHC) were found and their percentages were similar in all three muscles. The absolute expression of MyHC was greater in the VM than in the respiratory muscles, with a relative predominance of the MyHC I isoform in the DFG and VM muscles and a similar tendency in the EI muscle. Membrane damage was very slight in all three muscles.

CONCLUSIONS

The phenotype characteristics of respiratory and peripheral muscles in the beagle correspond to what we would expect functionally for a breed initially selected for hunting, with minimal lesions under normal circumstances, a predominance of fibers and proteins that are resistant to fatigue, and larger fibers in the EI, a muscle that plays a role in respiration in dogs.

Muscle fiber composition and capillarization in relation to metabolic alterations in hypertensive men

The aim of this study was to determine if there is a relationship among skeletal muscle fiber composition, capillarization, blood pressure (BP) and/or the components of the metabolic syndrome. Two groups were compared: 8 recently diagnosed, untreated, hypertensive men (BP > or = 140/90) and 7 normotensive men as controls. Muscle biopsies were taken from the vastus lateralis part of quadriceps femoris muscle in order to assess: fiber type proportion, capillarization, hexokinase, citrate synthase, beta-hydroxyacyl CoA dehydrogenase activities; lipoprotein lipase mass and activity, free fatty acids and triglycerides. Serum levels of insulin, glucose, cholesterol, uric acid and triglycerides were also assayed. Hypertensive patients had higher insulin levels and insulin resistance [homeostasis model assessment (HOMA)], a decreased hexokinase activity and an increase of muscle lipoprotein lipase mass as compared to controls. Interestingly, correlations among values differ in each group. The percentage of type IIB fibers was related to diastolic BP (blood pressure) in control and to mean BP in hypertensive subjects. Serum cholesterol and glucose were inversely related to the percentage of type I fibers in the control subjects. Negative correlations between capillarization and glucose, cholesterol and uric acid levels were found in control subjects. In all subjects, a strong correlation was found between SBP (systolic BP) and DBP (diastolic BP), and insulin resistance (IR) and uric acid levels. Muscle fiber type proportion and capillarization were related to blood pressure and components of the metabolic syndrome.