Biomedical subjects

E Redondo

Publications and source records attributed to E Redondo.

At least 19 recordsLinked to original sources

PubMed2004

Morphometric and immunohistochemical study of the rumen of red deer during prenatal development.

Abstract A detailed study of the ontogenesis of deer stomach has not been undertaken to date, and our aim was to sequence several histological phenomena that occur during the ontogenesis of one of the gastric compartments, the rumen. Histomorphometric and immunohistochemical analyses were carried out on 50 embryos and fetuses of deer from the initial stages of prenatal life until birth. For the purposes of testing, the animals were divided into five experimental groups: group I, 1.4-3.6 cm crown-rump length, 30-60 days, 1-25% of gestation; group II, 4.5-7.2 cm crown-rump length, 67-90 days, 25-35% of gestation; group III, 8-19 cm crown-rump length, 97-135 days, 35-50% of gestation; group IV, 21-33 cm crown-rump length, 142-191 days, 45-70% of gestation; and group V, 36-40 cm crown-rump length, 205-235 days, 75-100% of gestation. The rumen of the primitive gastric tube was observed at approximately 60 days. At 67 days the rumen consisted of three layers: internal or mucosal, middle or muscular, and external or serosal layer. The stratification of the epithelial layer was accompanied by changes in its structure with the appearance of ruminal pillars and papillae. The outline of the ruminal papillae began to appear at 142 days of prenatal development as evaginations of the basal zone toward the ruminal lumen, pulling with it in its configuration the stratum basale, the lamina propria and the submucosa. From the pluripotential blastemic tissue at 60 days we witnessed the histodifferentiation of the primitive tunica muscularis, composed of two layers of myoblasts with a defined arrangement. It was also from the pluripotential blastemic tissue, at 97 days, that the lamina propria and the submucosa were differentiated. The serosa showed continuity in growth as well as differentiation, already detected in the undifferentiated outline phase. The tegumentary mucosa of deer rumen was shown without secretory capacity in the initial embryonic phases; neutral mucopolysaccharides appeared from 67 days. The presence of neuroendocrine cells (non-neuronal enolase) in the ruminal wall of deer during development was not detected until 97 days. The glial cells were detected at 142 days for glial fibrillary acidic protein and at 67 days for vimentin. The immunodetection of neuropeptides vasointestinal peptide and neuropeptide Y progressively increased with gestation period, starting from 97 days. In terms of the structure of the rumen of the primitive gastric tube, our observations revealed that the deer is less precocious than small and large domestic ruminants. Thus its secretory capacity, detected by the presence of neutral mucopolysaccharides, and its neuroendocrine nature, determined by the presence of positive non-neuronal enolase cells, were evident in more advanced stages of prenatal development than those detected in the sheep, goat and cow.

Animals↗

PubMed2003

A Leishmania infantum multi-component antigenic protein mixed with live BCG confers protection to dogs experimentally infected with L. infantum.

The capacity of a quimeric protein, formed by the genetic fusion of five antigenic determinants from four Leishmania proteins, formulated with BCG, to protect dogs against Leishmania infantum infection is described. The data showed that after i.v. administration of 500,000 parasites of the L. infantum M/CAN/ES/96/BCN150 strain, zymodeme MON-1, the animals became infected as suggested by the humoral response against the parasite antigens. All control unvaccinated dogs had parasites in the lymph nodes at day 150 post-infection. One of these unvaccinated infected dog was parasite negative at day 634 behaving, thus, as resistant. In contrast, only 50% of the immunized dogs had parasites in the lymph nodes at day 150 post-infection. Four of these dogs became parasite negative by day 634 post-infection. The control animals developed at various times during the follow-up period clinical symptoms associated with Leishmaniasis. The control diseased dogs developed also in the liver and spleen some of the abnormal histological features associated with natural visceral Leishmaniasis. The immunized dogs, however, were not only normal at the clinical but also at the anatomo-pathological level. A positive delayed type hypersensitivity (DTH) response was observed in nine of the immunized protected dogs. The data indicated that Q+BCG confers 90% protection against infection and at least 90% protection at the clinical level.

Animals↗

PubMed2003

Day-night changes in plasma melatonin levels, synaptophysin expression and ultrastructural properties of pinealocytes in developing female sheep under natural long and short photoperiods.

The aim of the present study was to analyze the 24-h rhythm in plasma melatonin concentration and the day-night differences in synaptophysin expresion and ultrastructural characteristics of the pinealocytes in developing female sheep. Ewes of three different ages were examined: infantile (1-6 months old), pubertal and early fertile age (9-24 months old) and adult (36-60 months old). Experiments were conducted under natural non-stimulatory (long) and stimulatory (short) photoperiods. The obtained results were similar for both analyzed photoperiods. Plasma melatonin concentration, measured in samples obtained every 4 h, showed a similar pattern in the three age groups, with peak values at 02:00 h and troughs at 14:00 h. Mean value of plasma melatonin levels in 9-24 month-old sheep was significantly greater than that in younger or older sheep. The weight of pineal glands obtained at night (02:00 h) was significantly higher than in daylight (14:00 h). Pubertal and early fertile sheep had the largest pineal glands. The pineal volume, and the total number of pinealocytes per gland of 9-24 months-old sheep differed significantly from that of younger or older sheep. The pineal volume, and the mean volume of pinealocytes was significantly greater in animals killed at night. Number of pinealocytes did not vary between animals killed during daylight or at night. The mean volumen of pinealocytes did not show statistical differences between the age groups. In quantitative ultrastructural analysis of pinealocyte cells, the relative volume of mitochondria, rough endoplasmic reticulum and Golgi complexes was significantly greater in 9-24 month-old sheep and in animals killed at night. The relative volume of lipid droplets was highest in older sheep. Collectively, the data support the existence of developmental changes in pinealocyte morphology and quantity, partially in coincidence with a higher melatonin secretion rate.

Animals↗

PubMed2003

Postnatal development of female sheep pineal gland under natural inhibitory photoperiods: an immunocytochemical and physiological (melatonin concentration) study.

The purpose of this study was to determine structural and immunocytochemical changes taking place during the day and at night in developing sheep pineal gland under natural non-stimulatory photoperiods (summer solstice). Additionally, the diurnal cycle of plasma melatonin levels was charted and differences between diurnal and nocturnal pineal melatonin concentrations were analyzed. 36 ewes of three different ages were examined: infants (1-6 months old), pubertal and early fertile age (9-24 months old) and adults (36-60 months old). Plasma and pineal gland melatonin levels were higher in pubertal sheep than in infants or adults. Pubertal sheep pineal glands were also heavier, contained a larger number of pinealocytes and interstitial cells and displayed more evident innervation and vascularisation than infants or adults. There was no difference in the number of pinealocytes and interstitial cells between animals killed during daylight or at night. Gland weight, pinealocyte nuclear profile areas and plasma melatonin concentrations were all significantly higher at night than during the day.

Analysis of Variance↗

PubMed2001

Plant viruses and the recent discovery of unforeseen basic cellular processes.

Given their small genome size, the biological cycle of plant viruses is tightly integrated with the cellular processes of their host plants, so that studies of the viral biology will often provide insights into basic cellular processes. In the last decade, two such unforeseen mechanisms were discovered. One concerns intercellular communications: for their movement in infected plants, viruses use channels (plasmodesmata, phloem) also used by the plant to exchange information-rich molecules (proteins, RNAs) between cells. The second phenomenon concerns the existence, in plants, of an anti-viral defence mechanism based on the specific degradation of RNA molecules in the cytoplasm. This same mechanism, also allowing the regulation of gene expression (post-transcriptional gene silencing, PTGS) now appears to be widespread in pluricellular organisms. Besides their general interest, these new results modify drastically our vision of interactions between plant and viruses and raise numerous new research questions.

Cell Communication↗

PubMed2001

Lettuce mosaic virus pathogenicity determinants in susceptible and tolerant lettuce cultivars map to different regions of the viral genome.

Full-length infectious cDNA clones were constructed for two isolates (LMV-0 and LMV-E) of Lettuce mosaic virus (LMV), a member of the genus Potyvirus. These two isolates differ in pathogenicity in susceptible and tolerant-resistant lettuce cultivars. In susceptible plants, LMV-0 induces mild mosaic symptoms, whereas LMV-E induces severe stunting, leaf deformation, and a necrotic mosaic. In plants carrying either of the two probably allelic recessive resistance genes mol1 or mol2, LMV-0 is restricted partially to the inoculated leaves. When a systemic invasion does occur, however, symptoms fail to develop. LMV-E overcomes the protection afforded by the resistance genes, resulting in systemic mosaic symptoms. Analysis of the behavior of recombinants constructed between the two virus isolates determined that the HC-Pro protein of LMV-E causes the severe stunting and necrotic mosaic induced by this isolate in susceptible cultivars. In contrast, the ability to overcome mol resistance and induce symptoms in the resistant-tolerant cultivars was mapped to the 3' half of the LMV-E genome. These results indicate that the ability to induce severe symptoms and to overcome the protection afforded by the recessive genes mol1 or mol2 are independent phenomena.

Cloning, Molecular↗

PubMed2001

Ultrastructural study of ovine pulmonary pasteurellosis: involvement of neutrophils and macrophages.

Pasteurellosis is a common infectious disease characterised by fibrinous pneumonia and involving neutrophils and macrophages. This study aimed to determine the timing and extent of the pathogenic involvement of these cell elements in lesions induced in experimentally-infected lambs. A concentration of approximately 3x10(8) bacteria/ml. was inoculated into 30 two-month-old disease-free Merino lambs. Five lambs were assigned to each of five experimental batches, slaughtered on days 1, 3, 7, 11 and 15 following intratracheal inoculation, and to one control batch inoculated with a sterile solution. One control animal was slaughtered at the same time as each experimental batch. More characteristic lesions occur in bronchioles, peribronchial tissue and alveoli and are characterised by fibrinous processes. From the start of the experiment, epithelial-cell disruption and loss of microvilli were apparent; cell debris, desquamate cells and bacterial elements were observed in bronchiolar lumina, embedded in a fibrillar granular material. Alveolar structures displayed fewer neutrophils and macrophages, containing phagocytic vacuoles. Laminar bodies were apparent in type II pneumocytes. The interseptal area contained similar cell types, as well as abundant edema. In the course of the experiment, macrophage numbers increased in all the areas involved, with signs of intense phagocytic activity. The final phase of the experiment was characterised by a mild interseptal infiltrate and by clear alveolar lumina.

Animals↗

PubMed2001

Ultrastructural and immunocytochemical characterization of interstitial cells in pre- and postnatal developing sheep pineal gland.

Pineal gland interstitial cells from 32 sheep embryos (from day 54 of gestation until birth) and 18 sheep (from 1 month to >2 years) were analysed using ultrastructural and immunohistochemical techniques. From day 98 of gestation and throughout postnatal development, a second cell type was observed in addition to pinealocytes; these cells displayed uniform ultrastructural features similar to those of CNS astrocytes. Ultrastructural homogeneity was not matched by the results of histochemical and immunohistochemical analysis. Expression of phosphotungstic acid hematoxylin, glial fibrillary acidic protein and vimentin indicates that the second cell population in the developing ovine pineal gland is, in fact, a combination of glial-astrocyte cells at varying stages of maturity. Pineal interstitial cells started to show signs of functional activity evident in vascular tropism; such activity, evident from around day 98 of gestation, appeared to relate to the exchange of substances between the pineal parenchyma and blood vessels and, though it continued throughout postnatal development, was most evident in animals slaughtered between 9 months and 2 years of age (group II). Morphologically, functional activity in interstitial cells in this age-group was apparent in: 1, formation of specific contact sites between interstitial cells and nerve fibres in the perivascular space; and 2, the presence of numerous gap junctions between the bulbous endings of cytoplasmic processes.

Animals↗

PubMed2001

[Adrenocortical macronodular hyperplasia with massive enlargement of the gland. A rare variant of autonomous hypercortisolism].

OBJECTIVE: To present a case of Cushing's syndrome due to massive adrenocortical macronodular hyperplasia that gave the gland the appearance of a pseudotumor. METHODS: In a review of the surgical pathology of the adrenal gland recently performed in our hospital, 82 adrenalectomy specimens obtained from 1978-1998 were found. Of these 82 surgical specimens, 44 (53.6%) were cortical pathologies and 10 of these (12.1%) were hyperplasia. There was only one with massive adrenocortical macronodular hyperplasia. A 53-year-old male, chronic alcoholic with cushingoid obesity and hypercortisolism is described. RESULTS: Ultrasound and CT assessment showed enlarged, asymmetrical adrenal glands and macronodules. The analytical and MRI study of the sella turcica showed primary adrenal hypercortisolism. Adrenalectomy of the dominant gland (the left adrenal whose activity was demonstrated on the 131Iodine scintiscan) was performed. The postoperative cortisol levels returned to normal and remain normal up to the present time, 18 months after surgery. The surgical specimen weighed 104 gms and was completely macronodular. CONCLUSIONS: Massive adrenocortical macronodular hyperplasia is a rare cause of pituitary-independent autonomous primary adrenal hypercortisolism. It is always bilateral. Adrenal weight is significantly increased (total weight of both adrenals 60-180 gms) and present yellow or golden, non-encapsulated nodules of a few millimeters to up to 4 cms, comprised of cells with scanty activity, therefore massive enlargement of the glands is necessary to produce Cushing's syndrome. The clinical, biochemical and surgical aspects can cause confusion and can be suggestive of an adrenocortical neoplasm. Treatment is by adrenalectomy.

Adrenal Cortex↗

PubMed2000

Loss of heterozygosity on the short arm of chromosome 3 in renal cancer.

3% of human cancers are renal cell carcinomas (RCC). The most common chromosome abnormality found in this tumor is loss of heterozygosity (LOH) on the short arm of chromosome 3, which suggests that there must be one or more tumor suppressor genes between 3p14 and 3p21 near the VHL gene which play a relevant role in renal cancer development. DNA from normal and tumor tissue from 40 patients at various stages of RCC was analyzed for LOH at three microsatellites mapped to 3p (3p14.1-14.3; 3p21.2-21.3 and 3p25) by polymerase chain reaction). 42.5% of the tumors studied showed LOH on at least one locus. 30% showed LOH on only one locus; 5% on two loci and 7.5% on the three loci tested. LOH occurred only on nonpapillary tumors (p = 0.03). Interestingly, all the tumors with LOH on 3p21 were >/=25 mm (p = 0.04; relative risk 1.76, confidence interval: 1.3-2.3).

Adult↗

PubMed2000

In situ hybridization detection of bovine respiratory syncytial virus in the lung of experimentally infected lambs.

We studied the distribution of bovine respiratory syncytial virus (BRSV) RNA in lungs of experimentally inoculated lambs by in situ hybridization at different times postinoculation. The probe used for in situ hybridization was prepared by reverse transcription of BRSV RNA, followed by polymerase chain reaction (PCR) amplification of the cDNA. Twenty-five Merino lambs of both sexes with a live weight of 17 +/- 3 kg received an intratracheal inoculation of 20 ml saline solution containing 1.26 X 10(6) TCID50 BRSV (strain NMK7)/ml. Lambs were slaughtered 1, 3, 7, 11, and 15 days postinoculation (PID). Bronchial and bronchiolar epithelial cells were positive for BRSV nucleic acid by ISH at 1, 3, 7, and 11 PID. However, alveolar epithelial cells contained positive cells at 1, 3, and 7 PID. Cells containing viral RNA were detected from 1 to 11 PID in exudate within bronchial and bronchiolar lumina and from 3 to 7 PID in alveolar exudates. Positive hybridization signals were identified in interstitial mononuclear cells and in bronchi-associated lymphoid tissue from 3 to 11 PID. Mononuclear cells were located in peribronchiolar tissue and interalveolar septa. The highest signal intensity in positive cells was observed at 3 and 7 PID, coinciding with the most important histopathological findings.

Animals↗

PubMed2000

[5'CpG island methylation of the suppressor gene p16/CDKN2/MTS1 in renal carcinoma].

OBJECTIVE: To determine the methylation status of the tumor suppressor gene p16 in patients with renal carcinoma by analysis of microsatellite polymorphisms. METHODS: 40 patients with sporadic renal cancer were studied. Tumor and normal tissue from each patient were tested for methylation status of the p16 gene by analysis of microsatellite polymorphisms. RESULTS: 20% showed methylation of p16. No correlation was found between this genetic alteration and tumor features. CONCLUSIONS: Methylation of p16 was found in 20% of the patients in this series. According to the analysis, 18.5% of renal cell carcinomas showed methylation, 50% of chromophobe cell carcinomas and 25% of carcinomas of Bellini's tubules. The rest of the histological types showed no methylation.

Adult↗

PubMed2000

[Loss of heterozygosity in the 9p21 region as an inactivation mechanism of the p16 suppressor gene].

OBJECTIVE: To determine the loss of heterozygosity (LOH) on 9p21 (locus D9S1747) in patients with renal carcinoma by analysis of microsatellite polymorphisms. METHODS: 40 patients with sporadic renal cancer were studied. LOH on 9p21 was performed by analysis of microsatellite polymorphisms. RESULTS: 23.7% showed LOH on 9p21. No correlation was found between this genetic alteration and tumor features. CONCLUSIONS: LOH on 9p21 was found in 23.7% of the patients in this series. LOH was found in 26.9% of renal cell carcinomas, 25% of papillary carcinomas and 25% of Bellini duct carcinomas. LOH was not found in the other histological types.

Adult↗

PubMed1999

[Recurring invasive thymoma of the diaphragm].

Diaphragmatic recurrence of a thymoma is rare. We report the case of a 70-year-old woman who underwent transternal thymectomy and adjuvant radiation therapy, and who was admitted four years later with recurrence of the thymoma in the left hemidiaphragm with infiltration of the inferior ipsilateral pulmonary lobe. The thymoma was excised along with the left hemidiaphragm, chest wall and three ribs and an atypical segmentectomy of the left lower lobe was performed. The hemidiaphragm was reconstructed and the chest wall was repaired with synthetic mesh. Surgery was complemented with radiotherapy.

Aged↗

PubMed1999

[Fortuitous diagnosis of an undifferentiated large cell carcinoma during cardiac surgery].

A 57 years old man was operated for aortic valve replacement. During the operation a mediastinal lymph node was biopsed with the result of undifferenciated large cell carcinoma with neuroendocrine features. Three months after surgery the patient died of non-cardiac related reasons, postmorten examination was not performed. Although the primary tumor could not be assessed, probably the lung was the original location. The histological classification of lung cancer is exposed, with special reference in the undifferenciated large cell type with neuroendocrine features.

Carcinoma, Large Cell↗

PubMed1998

Structure of the ovine pineal gland during prenatal development.

The structure of the pineal gland of 32 clinically healthy ovine embryos at different stages of development was studied. Embryos were arranged in four age groups, each containing eight embryos (four males and four females), defined in terms of the most relevant histological features: group 1 (27 to 69 days of prenatal development), group 2 (70 to 97 days), group 3 (98 to 116 days), and group 4 (117 to 150 days). At around 30 days of prenatal life, according to topographic criteria, the pineal outline begins to differentiate into a dorsal evagination of the diencephalic medium line, close to the anterior and posterior commissures. The growth of the pineal is biphasic. The ontogenic-proliferative phase begins at 30 days and includes the invasion of ependymal cells and the proliferation of the pineal parenchyma cells. The hypertrophic-differentiation phase includes the volume increment of the pinealoblasts and their differentiation into pinealocytes; this occurs at around 118 days. At around 98 days, the gland acquires its definitive compact appearance due to 1) glandular growth in constant volume and 2) the obliteration of pineal recess. The glandular structure displays a parenchyma made up of pinealoblasts, interstitial cells, and cells containing pigment. The pineal stroma is structured in pseudolobes formed by reticular and collagen fiber septae, which constitute together the interstitial cell prolongation net, which is the support structure of the whole glandular cytology. Capillaries are detected all over the glandular surface, being more abundant in the medullary zone. At around 98 days of prenatal development, VIP (Vasoactive Intestinal Peptide) positive fibers, distributed around blood vessels and among pinealoblasts were detected.

Animals↗

PubMed1998

Presence of pigment in the ovine pineal gland during embryonic development.

Light- and electron-microscopic analyses were used to identify and describe the characteristic features of cells containing pigment in the ovine pineal gland during prenatal development. 72 ovine embryos (36 male, 36 female) ranging in age from 54 to 150 days were used for this study. Cells containing pigment granules were a constant feature in this gland. When samples from the different groups were inspected using the naked eye, the detection of pigment was of 61% in groups I (54 to 67 days of prenatal development) and II (71 to 92 days of prenatal development), 83% in group III (98 to 113 days of prenatal development) and 25% in group IV (118 to 150 days of prenatal development). The morphological features and histochemical properties of the pineal pigment enabled it to be identified as melanin. Several types of pigment granules were ultrastructurally distinguished; these varied in size, shape and location within pineal cell populations. The pigment granules were detected in pinealocytes, interstitial cells and pigmented cells. The largest amount and the widest variety of pigmented granules were found in pigmented cells. The presence of cells containing pigmented granules amongst the cell populations of the developing ovine pineal gland was analysed and compared with that of other mammalian species.

Animals↗

PubMed1998

Thyroid function in acute pancreatitis.

OBJECTIVES: To analyze changes in the thyroid function in patients with acute pancreatitis. METHODS: Admission serum levels of triiodothyronine (T3), reverse triiodothyronine (rT3), thyroxine (T4) and thyrotropin (TSH) were determined in 20 patients with pancreatitis and 20 healthy control patients. Another group of 20 patients with upper digestive haemorrhage was included to study possible changes in the pattern of thyroid function in hemodynamic alterations. In addition, laboratory indicators of liver, renal and pancreatic functions were measured in all groups. RESULTS: Our results demonstrated low levels of T3 in 20% of patients with pancreatitis and increased rT3 levels in 75% of them. Thyrotropin was always among reference ranges and only one case presented a low level of T4. No significant alterations were detected in patients with upper digestive haemorrhage. CONCLUSIONS: These results suggest that pancreatitis may play a role in the genesis of these changes, since other factors such as diet and cellular hepatic alteration appear to have had no effect on the levels of thyroid hormones in these patients. In other studies those changes in the thyroid function can be relationed with the prognosis in acute pancreatitis.

Acute Disease↗