[Autoantibodies against advanced glycation products in patients with type 1 diabetes mellitus]

BACKGROUND

Advanced glycation end products are associated with chronic complications of diabetes mellitus. This glycation process renders many proteins immunogenic.

AIM

To detect the presence of antibodies against albumin, collagen and low density lipoprotein glycation products in boys and teenagers with diabetes mellitus.

PATIENTS AND METHODS

Thirty one patients with diabetes mellitus type I, aged 11 +/- 3.8 years and with a mean duration of disease of 3.7 +/- 2.7 years and 31 healthy controls aged 12.4 +/- 5.3 years were studied. Antibodies against glycation end products were detected by ELISA and results were expressed as a ratio of the optical density of the glycated protein/optical density of the native protein.

RESULTS

Diabetic patients and healthy controls did not have antibodies against albumin glycation end products. Diabetics had higher levels of antibodies than controls for collagen glycation end products (2.6 +/- 0.4 and 1.8 +/- 0.2 respectively, p < 0.01) and low density lipoprotein glycation end products (3.07 +/- 0.92 and 2.2 +/- 0.72 respectively, p < 0.05).

CONCLUSIONS

The biological role of these antibodies is not clear. They could be a depuration mechanism for glycation end products or contribute to chronic complications of diabetes mellitus.

Kinetic modelling of aqueous atrazine ozonation processes in a continuous flow bubble contactor

The ozonation of atrazine in different waters (ultrapure and surface waters) has been studied in continuous bubble contactors with kinetic modelling purposes. Three ozonation processes have been considered: ozonation alone and combined with hydrogen peroxide or UV radiation. The kinetic models are based on a molecular and free radical mechanism of reactions, reaction rate and mass transfer data and non-ideal flow analysis models for gas and water phases through the contactors (the tanks in series model and the dispersion model). The models predict well the experimental concentrations of atrazine, dissolved ozone and hydrogen peroxide both at non-steady state and steady state regimes. From both experimental and calculated results, atrazine conversions are observed to be highly dependent on the nature of water where ozonation is carried out. As far as removal of atrazine and oxidation intermediates are concerned, ozone combined with UV radiation resulted in the most effective ozonation process among the three studied.

Effects of sea urchin-based diets on serum lipid composition and on intestinal enzymes in rats

The dietary effects of two high protein diets from two species of sea urchin (Paracentrotus lividus and Echinus esculentus) as compared to a reference protein such as casein on serum lipid levels and on intestinal disaccharidases and alkaline phosphatase were studied. After 23 days, the containing the two sea urchins as diets compared to casein decreased the cholesterol level and significantly increased the HDL-cholesterol in serum. The consumption of Echinus esculentus meal produced a significant decrease in lactase activity. The intestinal alkaline phosphatase activity increased not significantly in animals fed on the sea urchin meal.

Monoclonal antibodies against Der s 1, a major allergen of Dermatophagoides siboney

Six stable clones secreting murine monoclonal antibodies (Mabs) against Der s 1 were obtained. The binding of Mabs showed cross-reactivity with Dermatophagoides farinae, as determined by enzyme-linked immunosorbent assay (ELISA). In a Western blot assay, antibodies reacted with a 24-kD protein considered to represent the major allergen Der s 1. The repertoire of antigenic sites on Der s 1 was studied using a panel of Mabs. Epitope specificity of the Mabs was determined by both competitive inhibition and sandwich ELISA assays. The results defined six different, non-overlapping and non-repeated antigenic sites on the allergen molecule. Der s 1 allergen from Dermatophagoides siboney extracts was purified by Mab affinity chromatography, this procedure gave 43% recovery of >90% pure allergen. The purified allergen had capacity to bind specific human IgE and demonstrated an allergenic activity of up to 77% of total D. siboney extract. An Mab-ELISA was developed using Mabs directed against different epitopes on Der s 1. This assay could detect up to 1 ng/ml of Der s 1 and Der f 1 in allergen preparations.

Synthesis and biological evaluation of 1,2,5-oxadiazole N-oxide derivatives as potential hypoxic cytotoxins and DNA-binders

Several new 1,2,5-oxadiazole N-oxide derivatives were synthesized to be tested both as potential selective hypoxic cell cytotoxins and as DNA-binding agents. The compounds prepared included bis(1,2,5-oxadiazole N-oxide) derivatives and oxadiazole rings linked to naphthyl residues. The compounds were tested for their cytotoxicity in oxia and hypoxia and they proved to be non-selective and less active than the parent compounds 3-formyl-4-phenyl-1,2,5-oxadiazole N2-oxide (3) and 3-chloromethyl-4-phenyl-1,2,5-oxadiazole N2-oxide (4). The DNA-affinity assays showed that the compounds tested have poor affinity for this biomolecule.

[Obtention, characterization of antigens and evaluation of the immunotransfer technique for the detection of systemic candidiasis]

A culture media containing peptone, glucose, yeast extract and serum was evaluated to promote the development of the mycelium formation in Candida albicans and it was compared with the commercial media Tc 199. No significant difference was found between them. Somatic antigens characterized by PAGE-SDS were obtained from yeast and mycelial forms. Proteins reported as having high diagnostic value were expressed in both antigens. It was determined by immunotransference that the antigenic proteins predominating in the mycelium formation had molecular weights of 19, 21, 27 and 57 Kda. The immunotransference was standardized for detecting antibodies in patients with systemic candidiasis. 24 positive sera were evaluated by this technique and it was compared with the ELISA technique, which proved to be more sensitive and less specific. The most recognized proteins were those of 136 and 21 Kda and the complex from 42 to 45 Kda.

Sustained gastrointestinal colonization and systemic dissemination by Candida albicans, Candida tropicalis and Candida parapsilosis in adult mice

The ability of nine clinical isolates of Candida species (three C. albicans, three C. tropicalis and three C. parapsilosis) to colonize and invade the gastrointestinal (GI) tract of adult male CD-1 (ICR) mice was determined. The effect of dietary tetracycline plus glucose supplementation on colonization was evaluated. Strains were intragastrically inoculated. Tetracycline and glucose altered substantially aerobic flora, especially streptococci (average fall 1.1 +/-0.3 log(10) CFU/g, p<0.01 by the Student's t test). At two weeks after oral challenge, sustained and high colonization of GI tract by Candida (mean 5,28 +/- 0.18 log(10) CFU/g, p<0.01) was achieved in all mice receiving glucose-tetracycline supplementation, excepting in animals inoculated with one of C. tropicalis isolates. Histologic sections of the stomachs revealed multiple intraepithelial micro-abscesses associated with hyphae in the region of the cardial-atrium fold. Under immunosuppression, systemic spread of C. albicans and C. tropicalis was observed in 62% and 24% of animals receiving dietary supplementation respectively. Dissemination was not noted for C. parapsilosis isolates. We have developed a simple and inexpensive murine model of sustained colonization of GI tract. This model could be useful for analyzing prophylaxis, treatment and diagnosis of systemic Candida infections and for evaluating virulence of strains.

[Incidence of Aedes (S) aegypti and other Culicidae in the municipality of Playa, La Habana City]

An analysis was made on the incidence of Culicidae present in Playa Municipality, Havana City, during the intensive stage of the anti-aegypti campaign from June to July, 1997, according to its requirements. Culex quinquefasciatus was the predominant species with a total of 269 focuses. It was collected in all the People's Councils and in every type of repository, excepting clay repositories. The second most abundant species was the Aedes aegypti with 199 focuses, followed by Aedes mediovittatus with 67. The Almendares-Sierra, Ampliación-Almendares and Miramar People's Councils showed the highest values of Culicidae infestation in the municipality. The Aedes aegypti prevailed in the first and Cx. quiquefasciatus in the second. The artificial repositories, low tanks and other repositories had the highest number of mosquito focuses in the municipality. The Cx quinquefasciatus preferred the artificial depositories, whereas the A. aegypti preferred the low tanks. Most of the positive depositories were colonized by only one species (92.7% of the total). 7.3% corresponded to mixed focuses. It was found that Cx. quinqufasciatus and A. aegypti were the most associated species.

Linguistic development in cleft palate patients with and without compensatory articulation disorder

INTRODUCTION

Cleft palate patients frequently show compensatory articulation disorder (CAD). CAD severely affects speech intelligibility and requires a prolonged period of speech intervention. CAD has been considered a phonologic disorder. Thus, it seems necessary to explore the relationship between CAD and language development.

OBJECTIVE

To study the relationship between language development and the presence of CAD in cleft palate patients.

MATERIALS AND METHODS

Cleft palate children with residual velopharyngeal insufficiency (VPI) after palatal closure, with and without CAD were studied. Only patients with an age ranging from 3 to 8 years were included in the study group. Twenty-nine cleft palate patients with residual VPI and CAD were included in the first group (active). The second group was assembled with 29 cleft palate patients with residual VPI without CAD, matched by age and sex (control). For evaluating language development, all patients were analyzed using the Situational-Discourse-Semantic (SDS) Model [13]. This Model is a valuable tool for conducting naturalistic observation and descriptive assessment of language development. The SDS Model provides a detailed description of three contexts (situational, discourse, and semantic) in ten levels of cognitive and linguistic organization.

RESULTS

In all contexts considered by the model of cognitive and linguistic organization used for this study, i.e. SDS, a Fischer exact test demonstrated that patients with CAD showed a significantly higher frequency of language delay as compared with patients without CAD. None of the patients present with CAD showed an adequate level of language development. The degree of language delay was greater in the situational context as compared to the semantic and discourse contexts.

CONCLUSIONS

Cleft palate patients present with CAD, demonstrated a significantly higher frequency of delay in language development as compared with cleft palate patients present with VPI without CAD. From the results of this paper, it seems that a detailed evaluation of all aspects of cognitive and linguistic organization should be performed in cleft palate patients, especially in patients present with CAD. Moreover, it seems that speech intervention in cleft palate patients with CAD should address not only the articulation process, but also specific aspects of language development.

Crosstalk between cytosolic pH and intracellular calcium in human lymphocytes: effect of 4-aminopyridin, ammoniun chloride and ionomycin

Stimulation of lymphocytes by specific antigens is followed by the activation of different signal transduction mechanisms, such as alterations in the cytoplasmic levels of Ca(2+), H(+) and variations in membrane potential. To study interrelationships among these parameters, changes in pHi and Ca(2+) were measured with the fluorescent probes BCECF and Fura-2 in freshly isolated blood human lymphocytes. Moreover, membrane potential qualitative alterations were recorded with the fluorescent dye bis-oxonol. In a bicarbonate-free medium, cell alkalinization with NH(4)Cl slightly decreased intracellular Ca(2+) concentration ([Ca(2+)](i)) due to efflux of Ca(2+) from the cell. In contrast, an elevation of pHi induced with 4-AP increased [Ca(2+)](i), either in the presence or absence of external Ca(2+). The increase in Ca(2+)-free medium is likely to be due to Ca(2+) release from thapsigargin and caffeine-independent intracellular stores. Both 4-AP or NH(4)Cl induced a plasma membrane depolarisation, although with different kinetics. The ionosphere ionomycin increased pHi, Ca(2+) levels and also induced membrane depolarisation. Together, these observations demonstrate a lack of correlation between the magnitude of changes in pHi and Ca(2+).

The detection of contaminating clonal cells in apheresis products is related to response and outcome in multiple myeloma undergoing autologous peripheral blood stem cell transplantation

In the present paper, we report on the use of the heteroduplex PCR technique to detect the presence of clonally rearranged VDJ segments of the heavy chain immunoglobulin gene (VDJH) in the apheresis products of patients with multiple myeloma (MM) undergoing autologous peripheral blood stem cell (APBSC) transplantation. Twenty-three out of 31 MM patients undergoing APBSC transplantation with VDJH segments clonally rearranged detected at diagnosis were included in the study. Samples of the apheresis products were PCR amplified using JH and VH (FRIII and FRII) consensus primers and subsequently analyzed with the heteroduplex technique, and compared with those obtained at diagnosis. 52% of cases yielded positive results (presence of clonally rearranged VDJH segments in at least one apheresis). The presence of positive results in the apheresis products was not related to any pretransplant characteristics with the exception of response status at transplant. Thus, while no one patient with positive apheresis products was in complete remission (CR), negative immunofixation, before the transplant, five cases (46%) with negative apheresis were already in CR at transplant (P = 0.01). The remaining six cases with heteroduplex PCR negative apheresis were in partial remission before transplant. Patients with clonally free products were more likely to obtain CR following transplant (64% vs 17%, P= 0.02) and a longer progression-free survival, (40 months in patients transplanted with polyclonal products vs 20 with monoclonal ones, P = 0.03). These results were consistent when the overall survival was considered, since it was better in those patients with negative apheresis than it was in those with positive (83% vs 36% at 5 years from diagnosis, P= 0.01). These findings indicate that the presence of clonality rearranged VDJH segments is related to the response and outcome in MM transplanted patients.

Relevance of presenting white blood cell count and kinetics of molecular remission in the prognosis of acute myeloid leukemia with CBFbeta/MYH11 rearrangement

BACKGROUND AND OBJECTIVES

The detection of CBFbeta/MYH11 transcripts by RT-PCR has became a valuable and widely used technique in the accurate cytogenetic and molecular classification of acute myeloid leukemia (AML), but the clinical value of RT-PCR for monitoring minimal residual disease (MRD) during follow-up remains unclear.

DESIGN AND METHODS

We analyzed the factors predicting relapse and the value of MRD monitoring by RT-PCR in a series of 16 patients with CBFb/MYH11-positive AML (15 M4Eo; 1 M4). Fifteen were newly diagnosed cases (CR1) and one was studied after first relapse (CR2). Eight patients had clinical relapse at 6 to 19 months from the achievement of CR.

RESULTS

Presenting WBC count had a significant prognostic influence on disease-free survival (p=0.001). All four patients with a WBC count >100x10(9)/L relapsed, while only four additional relapses occurred among the eleven patients who had an initial WBC count below 100x10(9)/L. With regards to molecular monitoring, all relapses but one occurred in patients who showed persistent RT-PCR positivity during hematologic remission. By contrast, conversion to a repeatedly PCR-negative status was observed in the seven patients who remained in CR1 after a median follow-up of 48 months (range 31-79 months), as well as in the transplanted patient who was monitored in CR2. In these patients a PCR-positivity could be detected up to 24 months after diagnosis (median time to conversion to PCR-negative: 8 months).

INTERPRETATION AND CONCLUSIONS

In conclusion, marked hyperleukocytosis (>100x10(9)/L) confers poor prognosis to the patient with CBFbeta/MYH11-positive AML. In addition, slow kinetics of molecular remission was observed in this subset of AML, but the CBFb/MYH11 fusion transcript is no longer detectable in long-term survivors, indicating that molecular remission is an important therapeutic goal.

[Surgical treatment in a case of chronic progressive external ophthalmoplegia]

PURPOSE/METHODS

The purpose is to discuss the surgical result in a case with chronic progressive external ophthalmoplegia (CPEO) associated with strabismus and diplopia. The authors present a patient with mitochondrial myopathy and CPEO who was treated using adjustable recessions with local anaesthesia.

RESULTS/CONCLUSIONS

Five months after surgery improvement in ductions were maintained and there was no diplopia or torticollis. We support operating these cases with CPEO associated with strabismus. The adjustable suture technique allowed us a satisfactory result in immediate postoperative.

Synthesis and herbicidal activity of N-oxide derivatives

As part of an ongoing program on the chemistry and biological activity of N-oxide-containing molecules, a number of novel 1,2, 5-oxadiazole N-oxide, benzo[1,2-c]1,2,5-oxadiazole N-oxide, and quinoxaline N,N'-dioxide derivatives were synthesized and evaluated for their herbicidal activity. Many of these compounds exhibited moderate to good herbicidal pre-emergence activity against Triticum aestivum. Dose-response studies were done on the more representative compounds (12, 20, and 26). The most active compound, butylcarbamoylbenzo[1,2-c]1,2,5-oxadiazole N-oxide, 26, displayed herbicidal activity at concentrations as low as 24 g/ha.

Allogeneic peripheral stem cell transplantation in a case of hereditary sideroblastic anaemia

We report on a case of pyridoxine refractory hereditary sideroblastic anaemia (HSA) in a 19-year-old man who underwent peripheral blood stem cell transplantation (PBSCT) from his HLA-identical brother. By using short tandem repeat polymorphism, 100% donor cells were observed in peripheral blood on day +21; bone marrow showed mixed chimaerism from day +21 to day +221, when 100% cells of donor origin were observed. The patient developed extensive chronic graft-versus-host disease with favourable response to treatment. When the haemoglobin range was normal, a programme of phlebotomies reduced serum ferritin levels. Three years after transplantation, the patient has an ECOG rating of 0, with completely normal haemoglobin values (15 g/dl). To our knowledge, this is the first PBSCT reported in a case of hereditary sideroblastic anaemia.