Low percentages of regulatory T cells in common variable immunodeficiency (CVID) patients with autoimmune diseases and its association with increased numbers of CD4+CD45RO+ T and CD21low B cells.

BACKGROUND: Common variable immunodeficiency (CVID) is a heterogeneous group of primary antibody deficiencies defined by marked reductions in serum IgG, IgA and/or IgM levels and recurrent bacterial infections. Some patients are associated with defects in T cells and regulatory T cells (Tregs), resulting in recurrent viral infections and early-onset autoimmune disease. METHODS: We analyzed whether there is an association between Tregs cells (CD4+CD25+CD127low and CD4+CD25+FoxP3+); memory T cells (CD4+CD45RO+); memory B cells (CD19+CD27-IgD-); and CD21low B cells (CD19+CD38lowCD21low); as well as autoimmune manifestations in 36 patients with CVID (25 women and 11 men, mean age 24 years), all by flow cytometry. RESULTS: Fourteen patients presented with autoimmune diseases (AI) (39%), including 11 with autoimmune thrombocytopenia (ITP) (31%); two with vitiligo (6%); one with systemic lupus erythematosus (LES) (3%); and one with multiple sclerosis (MS) (3%). CVID patients with AI had a reduced proportion of Tregs (both CD4+CD25+CD127low and FoxP3+ cells) compared with healthy controls. CVID patients with AI had expanded CD21low B cell populations compared with patients who did not have AI. A correlation between increased CD4+CD45RO T cell populations and reduced Tregs was also observed. CONCLUSIONS: Our results showed that 39% of patients with CVID had AI and reduced Tregs populations. Research in this area might provide noteworthy data to better understand immune dysfunction and dysregulation related to CVID.

Severe malaria in immigrant haematological patient.

Severe malaria is a life-threatening condition caused by Plasmodium falciparum. Rupture of red blood cells when merozoites release to the bloodstream is responsible for the clinical manifestations, febrile fever reaching 39 °C, and other unspecific symptoms. P. falciparum is considered as the worst form of malaria. Moreover, this species has cytoadherence to red blood cells. This can lead to an organic dysfunction. People coming from hyper endemic areas have developed a partial immunity, but immunodepressed people are a group with a greater risk. Due to the high mortality rate associated to this disease, early diagnosis and a prompt treatment implementation are essential. However, the missed or delayed diagnosis is one of the major reasons of reaching a severe malaria disease. This case reflects the complexity of the diagnosis in an immigrant and immunodepressed patient with a haematological neoplasm with a severe infection by P. falciparum due to the unspecified symptoms and the overlapping of the same.

Undernutrition during foetal and post-natal life affects testicular structure and reduces the number of Sertoli cells in the adult rat.

To test whether undernutrition during foetal to pre-pubertal life would have long lasting effects on testicular histology in adult male offspring, eleven adult Sprague-Dawley pregnant rats were divided into two groups: Control group, n = 4, fed ad libitum, during gestation and lactation (until 25 day post-partum). Underfed group pregnant females (n = 7) were kept in cages where only dams had access to food (standard rat chow, 33.5% of ad libitum intake of Control group pregnant dams). After parturition, litters were adjusted to either 14 (Underfed group) or eight (Control group) pups. Mothers were weighed weekly. At 25 day of age pups were weaned, housed at four animals per cage, fed ad libitum and weighed weekly until euthanized at 100 day of age. Testes were processed for standard histology and morphometrical evaluation. At weaning, mother weight was lower in underfed than in Control group (mean +/- SD): 214.1 +/- 26.2 g vs 361.9 +/- 33.1 g. Body weight at 100 days of age (254 +/- 26.9 g vs 342.4 +/- 10.2 g, p

Spring constants and adhesive properties of native bacterial biofilm cells measured by atomic force microscopy.

Bacterial biofilms were imaged by atomic force microscopy (AFM), and their elasticity and adhesion to the AFM tip were determined from a series of tip extension and retraction cycles. Though the five bacterial strains studied included both Gram-negative and -positive bacteria and both environmental and laboratory strains, all formed simple biofilms on glass surfaces. Cellular spring constants, determined from the extension portion of the force cycle, varied between 0.16+/-0.01 and 0.41+/-0.01 N/m, where larger spring constants were measured for Gram-positive cells than for Gram-negative cells. The nonlinear regime in the extension curve depended upon the biomolecules on the cell surface: the extension curves for the smooth Gram-negative bacterial strains with the longest lipopolysaccharides on their surface had a larger nonlinear region than the rough bacterial strain with shorter lipopolysaccharides on the surface. Adhesive forces between the retracting silicon nitride tip and the cells varied between cell types in terms of the force components, the distance components, and the number of adhesion events. The Gram-negative cells' adhesion to the tip showed the longest distance components, sometimes more than 1 microm, whereas the shortest distance adhesion events were measured between the two Gram-positive cell types and the tip. Fixation of free-swimming planktonic cells by NHS and EDC perturbed both the elasticity and the adhesive properties of the cells. Here we consider the biochemical meaning of the measured physical properties of simple biofilms and implications to the colonization of surfaces in the first stages of biofilm formation.

Evidence for DNA charge transport in the nucleus.

Oxidative damage to DNA bases in isolated HeLa nuclei occurs upon treatment with rhodium intercalators and photoactivation. Oxidation occurs preferentially at the 5'-guanine of 5'-GG-3' sites, indicative of base damage by DNA-mediated charge transfer chemistry. Moreover, oxidative damage occurs at protein-bound sites which are inaccessible to rhodium. Thus, on transcriptionally active DNA within the cell nucleus, DNA-mediated charge transport leads to base damage from a distance, and direct interaction of an oxidant is not necessary to generate a base lesion at a specific site. These observations require consideration in designing new chemotherapeutics and in understanding cellular mechanisms for DNA damage and repair.

Influence of remote substituents on the equatorial/axial selectivity in the monooxygenation of methylene C--H bonds of substituted cyclohexanes.

The reactivity of individual C--H bonds in the methyl(trifluoromethyl)dioxirane TFDO oxygenation of stereogenic methylene groups in conformationally homogeneous monosubstituted cyclohexanes (2) has been determined. The unexpectedly high occurrence of O-atom insertion into C--H(ax) bonds suggests an in plane trajectory attack in the oxygenation while the diastereoselectivity of the reaction is qualitatively interpreted on the basis of the distinct hyperconjugative stabilization by the substituent of diastereomeric transition states due to long-range through bond interactions.

Long-range guanine oxidation in DNA restriction fragments by a triplex-directed naphthalene diimide intercalator.

Naphthalene diimide (NDI), a powerful oxidant that binds avidly to DNA by intercalation, is seen to damage the 5' guanine of 5'-GG-3' sites by photoactivated charge transport through DNA. When covalently tethered to the center of a triplex-forming oligonucleotide and delivered by triplex formation within a pyrimidine.purine-pyrimidine motif to a specific site on a restriction fragment, NDI can photooxidize guanine over at least 25-38 bp in each direction from the site of binding. Charge migration occurs in both directions from the NDI intercalator and on both DNA strands of the target, but the oxidation is significantly more efficient to the 3' side of the triplex. NDI and octahedral rhodium intercalators, when tethered directly to the 5' terminus of the triplex-forming strand as opposed to the center, generate significant amounts of oxidative damage only in the immediate vicinity of the intercalation site. Given that long-range charge transport depends on DNA stacking, these results suggest that the base stack is distorted at the 5' end of the triplex region in the duplex-triplex junction. Targeting of photooxidative damage by triplex formation extends our previous studies of long-range charge transport to significantly longer DNA sequences through a strategy that does not require covalent attachment of the photooxidant to the DNA being probed. Moreover, triplex targeting of oxidative damage provides for the first time a typical distance distribution for genomic charge transport of approximately 200 A around the oxidant.

Probing DNA charge transport with metallointercalators.

A wide range of experiments have emerged recently regarding charge transport through DNA, including spectroscopic studies of rates of DNA-mediated electron transfer and biochemical studies of DNA base oxidation over long distances. These experiments have, in turn, led to new proposals about the way in which charge moves through DNA and have prompted the consideration of physiological roles for DNA electron transfer. Importantly, metallointercalators have been key players in many of these experiments. Metallointercalators provide critical probes to examine the migration of charge through the DNA base stack.

Respiratory allergy in Mexican patients with cystic fibrosis.

BACKGROUND: the purpose of this study was to investigate the presence of respiratory allergy in 30 Mexican patients bearing cystic fibrosis (CF). METHODS AND RESULTS: all patients completed a clinical history, had a physical examination, total serum IgE, nasal and blood eosinophils determinations and evaluation of skin prick tests for 36 allergens. In 26.6% of the patients included in the study was detected respiratory allergy diagnosed on clinical and laboratory analyses. Skin prick tests of 11 (36.6%) of the patients were positive to at least one allergen and Aspergillus fumigatus (A. fumigatus) was the most frequently observed allergen in 23% of the cases. CONCLUSIONS: we have demonstrated in this study that Mexican patients also present a coexistence of respiratory allergy in patients bearing CF.

Long-range oxidative damage to DNA: effects of distance and sequence.

INTRODUCTION: Oxidative damage to DNA in vivo can lead to mutations and cancer. DNA damage and repair studies have not yet revealed whether permanent oxidative lesions are generated by charges migrating over long distances. Both photoexcited *Rh(III) and ground-state Ru(III) intercalators were previously shown to oxidize guanine bases from a remote site in oligonucleotide duplexes by DNA-mediated electron transfer. Here we examine much longer charge-transport distances and explore the sensitivity of the reaction to intervening sequences. RESULTS: Oxidative damage was examined in a series of DNA duplexes containing a pendant intercalating photooxidant. These studies revealed a shallow dependence on distance and no dependence on the phasing orientation of the oxidant relative to the site of damage, 5'-GG-3'. The intervening DNA sequence has a significant effect on the yield of guanine oxidation, however. Oxidation through multiple 5'-TA-3' steps is substantially diminished compared to through other base steps. We observed intraduplex guanine oxidation by tethered *Rh(III) and Ru(III) over a distance of 200 A. The distribution of oxidized guanine varied as a function of temperature between 5 and 35 degrees C, with an increase in the proportion of long-range damage (> 100 A) occurring at higher temperatures. CONCLUSIONS: Guanines are oxidized as a result of DNA-mediated charge transport over significant distances (e.g. 200 A). Although long-range charge transfer is dependent on distance, it appears to be modulated by intervening sequence and sequence-dependent dynamics. These discoveries hold important implications with respect to DNA damage in vivo.

Bilateral hydatid cyst of pulmonary arteries: MR and CT findings.

The location of hydatid cysts inside pulmonary arteries has been reported only on rare occasions in the literature and is caused, in the majority of cases, by embolization due to the rupture of hydatid cysts located in the heart; more rarely, hematogenous dissemination from a hepatic focus is the cause. We report a case of a 44-year-old patient with hydatid cysts located in both the right and left pulmonary arteries, whose first clinical reference was hemoptysis. The patient had undergone surgery because of a hepatic hydatid cyst 5 months previously. The importance of this case lies in the infrequent bilateral location in both pulmonary arteries and in the absence of intracardiac hydatid cysts.

Oxidative charge transfer To repair thymine dimers and damage guanine bases in DNA assemblies containing tethered metallointercalators.

Potent oxidants which intercalate in DNA serve as tools to probe DNA-mediated electron-transfer reactions. A photoexcited rhodium intercalator, Rh(phi)2DMB3+ (phi = 9,10-phenanthrenequinone diimine and DMB = 4,4'-dimethyl-2,2'-bipyridine), tethered to DNA, promotes both oxidative damage to 5'-GG-3' doublets in DNA and the repair of thymine dimers from a remote site on the DNA duplex. DNA-mediated repair of a thymine dimer lesion by charge transfer from the tethered rhodium intercalator is quantitative, albeit with low photoefficiency, occurs in an intraduplex reaction over long range (36 A), and requires that the intervening bases be paired. When both oxidative reactions, repair and oxidative damage, are monitored on the same duplex, competition is evident; the presence of both a 5'-GG-3' site and the thymine dimer diminished the dimer repair efficiency by 20-40% and decreased damage at the 5'-GG-3' sites 2-fold compared to similar sequences lacking either the guanine doublet or thymine dimer, respectively. In addition to damage at the 5'-G of 5'-GG-3' sites, we also observe oxidation at the 3'-G of the 5'-GT<>TG-3' tetrad only in the presence of thymine dimer. Overall, the yield of repaired thymine strand was at least 10 times higher than the yield of oxidized guanine in the same sequences. While the 5-GG-3' may represent the thermodynamically favored site for oxidative reaction, repair of the thymine dimer appears to be kinetically more favorable. Dipyridophenanzine (dppz) complexes of ruthenium(III), less potent oxidants which intercalate in DNA, oxidize 5'-GG-3' doublets efficiently but cannot trigger the repair of the thymine dimer lesion. Oxidative damage to DNA from a distance, mediated by the DNA base pair stack, can, however, be utilized to probe the disruption in the base stack generated by the thymine dimer. The presence of the dimer does not diminish oxidation by a Ru(III) intercalator at a distal guanine doublet, suggesting that the disruption caused by the dimer does not block charge transfer through the DNA duplex. DNA-mediated electron-transfer reactions of metallointercalators therefore serve to illustrate important aspects of radical migration and its consequence with respect to reactions at a distance through the DNA base pair stack.

[Intramuscular myxoma. Apropos of a case]. / Myxome intramusculaire. A propos d'un cas.

Intramuscular myxoma is a relatively unusual benign tumor of soft tissues. Clinical examination is non specific and the definitive diagnosis can only be established on histology. The treatment consists of excision of the tumor. The prognosis is very good and recurrence is very rare. No cases of metastasis have been described.

Concentration and separation of hypoglycemic drugs using solid-phase extraction-capillary electrophoresis.

Solid-phase extraction-capillary electrophoresis (SPE-CE) is a technique whereby very dilute analytes may be selectively extracted from a sample matrix and concentrated on-line for analysis. This study describes the first phase in the development of a method exploiting this technique for the direct analysis of hypoglycemic drugs in urine. Effective separation and detection of six sulfonylurea drug standards at concentrations below the detection limit of conventional capillary electrophoretic techniques is shown to be attainable. Since surfactant interfered with the on-line concentration process, non-MEKC (micellar electrokinetic chromatography) separation conditions were defined. Using 250 mM borate/5 mM phosphate at pH 8.4, all drugs in a mixture at 285 ng/ml were effectively extracted, concentrated from an injected volume of 2.5 microliters, non-selectively desorbed with an organic-based elution buffer and electrophoretically resolved. Sample loading was found to be linear in the 0.12-1.9 microliters range and drugs in a volume of up to 190 microliters could be concentrated and detected with a sensitivity of approximately 5 ng/ml. Not only was resolution of the desorbed material uncompromised by the presence of the SPE-tip, but separation of glipizide and glyburide was observed despite the fact that these drugs were unresolved under the same separation conditions by standard capillary zone electrophoresis (CZE). From these results, it is clear that SPE-CE not only increases the sensitivity for detection but that selectivity may be altered due to chromatographic processes occurring on the solid-phase resin.

[How much time does the physician dedicate to his patients? A study of contents of office visits and their length]. / Cuánto tiempo le dedica a sus pacientes? Estudio del contenido de las consultas médicas según su duración.

OBJECTIVE: To describe the content and length of General Medicine interviews at a health centre, analysing the problems dealt with and activities undertaken, in function of the time taken. DESIGN: A crossover study. SETTING: An urban health centre at Alcobendas (Madrid). PATIENTS AND OTHER PARTICIPANTS: The problems, activities and length of all the interviews (926) were recorded over a period of 10 days. MEASUREMENTS AND MAIN RESULTS: The average length of the interviews was 6.7 minutes (standard error SE = 0.13). More problems were dealt with, and more activities carried out, in the longer interviews. Problems of a psycho-social character and preventive activities were discussed in the long interviews. Significant differences were found in the length of interviews in function of the patient's age and between different professionals. CONCLUSION: To achieve integrated care which includes both preventive medicine and psycho-social problems, doctors must have more interview time, as these questions are not tackled in short interviews.

[In vitro and in vivo acari tests]. / Pruebas in vitro e in vivo a ácaros.

We studied 40 children with one o more perennial allergic diseases (bronchial asthma, allergic rhinitis, and/or atopic dermatitis) to assess the value in our country of in vivo and in vitro tests more frequently used in the diagnosis of allergy, such as total serum IgE, specific allergen IgE (RAST) and prick skin test in patients sensitives to D. pteronissinus, D. farinae or both. All patients had positive prick skin tests. Total serous IgE was elevated in 95% of cases with poor correlation coefficient (r) between prick skin test reactivity and total serous IgE concentration with no statistical significance. On the other hand, 95% of patients showed a positive RAST with a correlation coefficient of 0.31 (p less than 0.05). We concluded that in our country clinical history and prick skin tests are sufficiently accurate in a reasonable way to make a diagnosis of allergic etiology in patients sensitives to mites of the house dust.

Cytogenic effects of diatrizoate and ioxaglate on patients undergoing excretory urography.

Possible cytogenic alterations due to radiologic contrast medium in patients undergoing a common radiologic examination is studied. Two groups of 20 patients each were used. Group I consisted of patients undergoing excretory urography, using sodium and meglumine diatrizoate as contrast. A different agent, sodium and meglumine ioxaglate, was used with group II. Three blood samples were taken from each patient before urography, immediately after urography, and 1 week later. The frequency of sister chromatid exchanges (SCE) and chromosomal aberrations (CA) were found to increase significantly in the B samples from both groups, that of group I being higher (P less than .01 compared with P less than .05). Furthermore, these alterations were found to persist in the C samples from group I. No modification of the Proliferating Rate Index (PRI) was found. The osmolarity or other components of the contrast media studied could be involved in the process. The results indicate that ioxaglate produces less cytogenic damage than diatrizoate.

[Periosteal desmoid]. / Desmoide perióstico.

A case of periosteal desmoid is studied. Being of a rather often incidence in children it might be confused with others lesions located on distal femoral metaphysis and which sometimes form part of pathology typical of the developing skeleton as cortical defects and non osteogenic fibromas and the others which might be a question of malignant process. Periosteal desmoid is characterized by appearing as a radiolucent lesion with periosteal speculation of the dorsomedial cortical wall of the medial femoral condyle, on adductor insertion zone. Simple radiology study in these lesions must be emphasized, without necessity to use more cruel techniques.