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Biomedical subjects

A Alonso

Publications and source records attributed to A Alonso.

At least 595 records · Page 33Linked to original sources
PubMedDate not supplied

Prognostic significance of high microsatellite instability in a Spanish series of gastric adenocarcinomas.

In colorectal cancer different levels of microsatellite instability (MSI) have been described. MSI-H (high) characterizes a unique clinical and pathological phenotype known as hereditary non-polyposis colorectal cancer syndrome, whereas MSI-L (low) and MSS (stable) are considered similar phenotypes without pathological implications. MSI has been also described as a frequent genetic alteration in a subset of gastric adenocarcinomas. However, the clinicopathological and prognosis significance of this abnormality in these tumors remains unclear. To investigate the role of genetic instability in gastric carcinogenesis we examined 10 microsatellite loci in 37 patients. MSI-H was found in 37.8% patients. We observed a trend of MSI-H tumors to be associated with elderly patients, intestinal histological type, advanced clinical stages and less aggressiveness with better survival. In conclusion, MSI-H can be considered as a good prognosis factor in a subset of gastric tumors.

Adenocarcinoma↗
PubMedDate not supplied

[Anesthetic management for cesarean delivery in a pregnant patient with congenital antithrombin III deficiency and pulmonary thromboembolism].

Antithrombin III (AT III) deficiency is a rare hereditary disease that predisposes a patient to thromboembolic complications. Anticoagulation is essential for preventing recurrence of thrombi. Concentrated AT III replacement is reserved for acute periods of thromboembolism or moments of increased risk. Hemostatic anomalies are generally considered a contraindication for regional anesthesia, due to the potential risk of spinal hematoma. This paper describes a woman with congenital AT III deficiency and heparin-treated pulmonary embolism whose pregnancy of 29 weeks had to be terminated by cesarean section upon signs of fetal distress. We discuss the pathophysiology and treatment in such cases.

Adult↗
PubMedDate not supplied

[Multiple symmetric lipomatosis associated to polyneuropathology, atrophy of the cerebellum and mitochondrial cytopathy].

INTRODUCTION: Multiple symmetric lipomatosis (MSL), which is predominantly found in middle aged males, is characterised by accumulations of fat in the neck, shoulders and other parts of the trunk, and sometimes associated with different neurological manifestations, both central and peripheral. Although its aetiology is unknown, it has been described as associated with mitochondrial cytopathies. AIMS. To describe the case of a young female with MSL associated with mitochondrial encephalomyopathy. CASE REPORT: Girl aged 14 with MSL, ataxia, patellar hyperreflexia, bilateral Babinski sign, pes cavus, axonal peripheral neuropathy, involvement of the optic pathway, atrophy of the cerebellum, subsarcolemmal mitochondrial accumulations in the untrastructural examination of the vastus lateralis muscle and partial deficit of complex I in the mitochondrial respiratory chain. As regards molecular genetic aspects, the most frequent mutations of the ATPase 6 gene in lymphocytes, and mtDNA deletions and tRNALys and tRNALeu(UUR) mutations in muscles were excluded. CONCLUSIONS: Despite the fact that MSL is an entity normally found in adults, the possibility of its being diagnosed in the paediatric age must be taken into account. This case is probably the second time MSL has been observed associated with mitochondrial cytopathy in this age bracket.

Adolescent↗
PubMedDate not supplied

IgE antibodies against Neisseria flavescens.

Bacterial allergy is still a matter of controversy. We sustain that this name should be employed only in the presence of a specific IgE against antigens from bacteria. In 100 atopic patients and 100 healthy controls with Neisseria flavescens in their pharyngeal exudates, we performed type I immediate skin tests with Neisseria flavescens and IgE-RAST throughout 1 year. Positive wheal and flare reactions were elicited in 8 of 100 atopic patients as well as in 3 of 100 nonatopic subjects. IgE-RAST/anti-Neisseria flavescens was found in 6 of the former group and in 1 of the latter. Neither late-phase nor Arthus-like reactions were recorded. Neisseria flavescens is a non-pathogenic commensal of the oropharynx with scarce antigenic properties and seems not to play an important role in these conditions (rhinitis/asthma). Bacterial immunotherapy should be considered only in the presence of specific IgE antibodies with careful selection of the bacteria or their antigens.

Adult↗
PubMedDate not supplied

Immunochemical properties of the antigens of Triatoma infestans.

Taxonomically related to the cockroach Periplaneta americana (Pa), Triatoma infestans (Ti) is an insect that parasitizes two-thirds of Argentina and acts as a vector for American trypanosomiasis. The glycoproteins obtained by a Sephadex G-150 column fractionation from the whole-body extract prepared with the chitinous structures revealed antigenicity in rabbits, which developed specific IgG after 8 weeks of immunization, as detected by several serological techniques. Atopic patients living in the northern provinces of Argentina--Santiago del Estero and Chaco (endemic area for Ti)--with rhinitis/asthma showed immediate positive skin tests to Ti and its fractions, as well as an IgE-RAST-anti-Ti in 30-36% of them. Healthy nonatopic adults of the same area and other atopics and nonatopics from Buenos Aires (non-endemic area) were selected as controls and showed negative type I skin tests, as well as specific RAST. The existence of common epitopes between Ti and Pa was confirmed by absorption techniques, RAST inhibition, IEF and STIF-RAST. These findings have clinical and epidemiological connotations.

Adult↗
PubMedDate not supplied

Interstitial pneumonitis induced in guinea-pigs by the antigens of Periplaneta americana.

Data concerning the experimental induction in guinea-pigs of hypersensitivity pneumonitis with a cockroach antigen are presented. A glycoprotein obtained from the chitinous structures of Periplaneta americana was aerosolized daily to guinea-pigs during 12 weeks. The presence of specific antibodies (IgG) was detected by serological techniques; histopathological studies of the lungs showed interstitial infiltrates of macrophages and LT-CD8+ cells, as revealed by the MoAb used. Single non-necrotizing granulomas were characteristic from the 10th week to the end of the experiment. The results from this animal model suggest that this hypersensitivity pneumonitis is a typical delayed-type reaction due to chronic contact with the heterologous glycoproteins of P. americana.

Alveolitis, Extrinsic Allergic↗
PubMedDate not supplied

[Exanthematous outbreak caused by human parvovirus B19 in a school in Banderaló, Argentina].

We report an exanthematic outbreak in a school of Banderaló town, located in the district of General Villegas, Buenos Aires province, Argentina. This outbreak affected 21 individuals, with a wide range of age (out of a total population of 1400). The observed clinical manifestations were exanthema and in some cases fever, asthenia, arthropathies and myalgia. The presence of specific IgM antibodies against measles, rubella and human parvovirus B19 were investigated. Analysis of IgM antibodies to parvovirus B19 by ELISA was positive in 90.8% of the cases and viremia was detected in 66.7% of the patients by nested PCR. These results indicate that human parvovirus B19 was the etiologic agent of the outbreak and they confirm its circulation in Argentina. Moreover, this study demonstrates that PCR may be useful for the study of transmission foci and of individuals with prolongued clinical manifestations. We consider that it is necessary to include the differential diagnosis of human parvovirus B19 in the surveillance of exanthematic virosis.

Adolescent↗
PubMedDate not supplied

[Interferon-beta response in multiple sclerosis associated with pre-treatment disability].

AIM: To study pre-treatment clinical features and influence of neutralising antibodies (NABs) in clinical response to interferon-beta (IFNB). PATIENTS AND METHODS: We analysed clinical characteristics and NABs to IFNB in 96 multiple sclerosis patients treated with IFNB. Clinical response was established by clinical criteria: = 1 relapse or an increase = 0.5 or 1 point in the Expanded Disability Status Scale (EDSS) score after one year of treatment compared with the year prior to IFNB therapy. RESULTS: Baseline clinical characteristics were similar for responders and non-responders, except for a significantly higher baseline mean EDSS score in non-responders. Time-to-first-relapse was longer and the number of patients relapse-free was higher for NAB-negative patients, but we were unable to show an association with the disability status, probably due to sample size. CONCLUSIONS: Response to IFNB was significantly associated with pre-treatment disability measured by the EDSS. The presence of NABs to IFNB presented a delayed negative effect for relapses.

Adolescent↗
PubMedDate not supplied

Antigenicity of Penicillium notatum in animals and in atopic patients.

A mycelial and metabolic extract of Penicillium notatum (PN) was passed through Sephadex G-50 and DEAE-cellulose columns in order to separate soluble fractions that revealed a complex composition. Their proteins and hexoses were recorded with a LKB Uvicord spectrophotometer and quantified by the Lowry and the indol techniques. On the other hand an animal model was developed in rabbits and an IgG precipitin and hemagglutinating antibodies were obtained. The PN extract as well as those fractions with the higher protein content appeared positive when they were checked against the antiserum by means of Ouchterlony, Boyden and immunoelectrophoresis. The molecular weight of PN was established in 52,000 daltons approximately in comparison with well known marker proteins. Adult human beings suffering perennial rhinitis and bronchial asthma showed positive type I skin tests with PN and its most conspicuous fractions (glycoproteins). A RAST-IgE-anti-PN was prepared following Ceska's procedure and challenged against all human sera. Only 40% of the patients revealed a positive RAST IgE-anti-PN which correlated significatively with the protein fractions (35%) and with the skin tests (43% and 39%, respectively). These results reinforced the idea that PN is a potent antigenic mold both in animals and in humans in whom we detected an IgE specific antibody presumably related to their atopic clinical condition.

Adolescent↗
PubMedDate not supplied

[Renal transplantation: surgery in the patient with a functioning kidney].

One hundred and seven surgical procedures performed on 98 patients with stable renal allograft function are analyzed. They represent 35.5% of 276 patients who underwent renal transplants. The surgical procedures were not related to the graft or its arteries and vein. The procedures were gynecologic 8, urologic 24, thoracic 6, ophthalmologic 8, neurosurgical 2, general surgery 37, orthopedic 17 and plastic surgery 5. Thirty-five (32.7%) were emergency and 72 (67.3%) elective procedures. Twenty-six patients were operated on for infections. The overall operative mortality rate was 15.3%. It was significantly higher in emergency procedures (34.28%) than in elective surgery (4.16%).

Adolescent↗
PubMedDate not supplied

[Amyloidosis maculosa: diagnosis in primary care].

Amyloidosis maculosa is a clinical entity with low incidence factor in our medium, which basically affects middle-aged women. The lesion is characterised by the presence of poorly defined, hyperpigmented, brownish or greyish maculae that converge and focus basically on the upper back and shoulders, usually accompanied by pruritus. Three patients were erroneously catalogued for years as having pityriasis versicolor. Two of these patients presented a typical clinical amyloidosis maculosa, and the third presented a less common manifestation of the disease: a single, well-defined lesion in the subscapular region. We believe that the approach to the diagnosis of pityriasis versicolor with hyperpigmented lesions that do not respond to specific treatment should be revised. Although amyloidosis maculosa has a low incidence in our medium, it is an entity which should not be discarded in these cases.

Adult↗
PubMedDate not supplied

Induction of anti-orange antibodies in rabbits.

The capacity of certain foods to cause allergic reactions is well known. The four types of mechanisms that Gell and Coombs described in 1968, are involved in these reactions, although the reaginic antibodies retain the paramount attention of the immunologists. The physiochemical composition of the allergen molecule is the goal of investigators with the purpose to clarify the intrinsic kinetics of antibody synthesis. This paper contributes to the conflicting data about orange allergens especially those obtained from Citrus Aurantium Sinensis and Citrus Silension (CAS and CS, respectively). Glycoproteins were separated by gel filtration through a Sephadex G-50 column. A definite protein peak was obtained meanwhile several hexoses appeared throughout the fractionation procedure. These molecules have adequate physiochemical properties that make them able to trigger the immunological response (molecular weight, definite chemical composition and glycoprotein content). Although CAS and CS have a similar chemical composition a slight inverse proportion of proteins and hexoses was demonstrated between the two classes. Molecular weights were different for CAS (51.500) and for CS (37.000) in comparison with well established protein makers. Ouchterlony revealed two precipitin lines in the CAS-anti-CAS system but none in the CS-anti-CS one. The Boyden technique showed a titre of 1/256 in the first case and only of 1/64 in the second of specific anti-orange antibodies. All the eluted fractions gave negative results although they were concentrated ten times by pre-evaporation. This animal model reinforced the statement that after a long and continuous exposure to orange antigens it was possible to develop specific antibodies. It is assumed that this phenomenon happens in atopic children with it's diagnostic and therapeutic importance.

Allergens↗
PubMedDate not supplied

Are serum zinc and copper levels useful as acute rejection markers in heart transplantation?

We assessed the usefulness of zinc and copper serum level changes as acute rejection markers in orthotopic heart transplantation. Mean serum zinc levels occurring without rejection were 74 +/- 1.9 micrograms/dl, whereas with rejection they were 67 +/- 3.2 micrograms/dl (p = 0.056). Mean serum copper levels occurring without rejection were 109 +/- 3.9 micrograms/dl, whereas with rejection they were 116 +/- 6.4 micrograms/dl (p = 0.32). Results of our study show that changes in serum zinc and copper levels are not useful as rejection markers in heart transplantation. Levels of these trace elements can be affected by clinical situation and therapy in heart transplant patients regardless of rejection.

Adult↗
PubMedDate not supplied

Immunochemical properties of the antigens involved in the pigeon breeder's disease.

The pigeon breeder's disease is a form of extrinsic allergic alveolitis caused by the exposure to pigeon droppings. Chemical analysis of this antigen was carried out employing column fractionation techniques. Sephadex G-50 and DEAE cellulose were performed and several proteins and hexoses peaks were recorded. Molecular weights were determined by comparison with standardized marker proteins passed through a drop counting fraction collector. The whole extract revealed a molecular weight of 100 Kd while fraction 1 showed 66 Kd and fraction 2 only 30 Kd. A guinea pig experimental model was developed with the whole extract injected by the intradermal route, administered by an intragastric catheter or aerosolized in a glass chamber. Histopathological studies were carried out with the lungs, kidneys, liver and spleen obtained by the necropsy of the animals. The lungs and the kidneys showed the paramount changes in their structures with lymphomononuclear infiltrates and an Arthus-like phenomenon surrounding the vessels. Immunological techniques were applied to the sera and the lymphocytes obtained from the animals. Precipitin and hemagglutinating IgG antibodies were detected against the whole extract and the fractions obtained by column fractionation. Sensitized lymphocytes were also detected. This experimental model represents a guide in the approach to the human allergic alveolitis whose immunological findings will be presented in a forth-coming report.

Alveolitis, Extrinsic Allergic↗