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Biomedical subjects

C Ferrer

Publications and source records attributed to C Ferrer.

At least 55 records · Page 3Linked to original sources
PubMed1993

Melanization stimulating activity in the skin of the gilthead porgy, Sparus auratus.

The presence of a melanization-stimulating factor (MSF) was discovered in dorsal and/or ventral skin of Sparus auratus. Skin from this marine species was used to condition Steinberg's balanced salt solution (BSS), which was subsequently tested with the neural tube assay. BBS conditioned by dorsal and/or ventral skin of S. auratus at 25% and 50% concentrations had a profound stimulatory effect on the percentage of melanization of neural crest cells throughout the 3-day assay period. In some cases 90% melanization occurred within the first 24 hr. Such stimulated cells showed a doubling of the number of dendrites per cell. To assess the effects of MSF on other indices of melanization, dorsal and/or ventral skin was used to condition MEM used in the culture of B16-F10 murine melanoma cells. During the first 24 hr, B16-F10 murine melanoma cells responded to conditioned media by demonstrating a considerable increase in activities of tyrosine hydroxylase, dopa oxidase, and dopachrome tautomerase, but no effect was observed on melanin content. In contrast, melanin content increased after 48 hr of incubation, whereas the enzymatic activities were inhibited during this period. It seems that MSF activity, expressed in several ways, may be present generally among marine species.

Animals↗
PubMed1993

[Tuberculosis and human immunodeficiency virus infection. A prospective study of 215 patients].

We analyze the cases of 215 adult patients affected from tuberculosis (TB) and infection due to human immunodeficiency virus (HIV) in the study period from December 6th, 1986 to January 31st of 1992. Disease affected specially the group of drug addict patients (DAP) with a 74.88%, followed by paid plasma donors (PPD) from our city with a 12.09%. Sexual transmission was the route of contamination with the HIV in 16 cases. In five cases atypical mycobacteria were detected. First-line anti-tuberculostatics drugs activity against Mycobacterium tuberculosis was excellent. A total of 17 cases with toxicity to any of these drugs were described. TB was located in the lung in 108 cases (50.23%), in 74 cases out of the lung (34.41%) and in 33 cases there was intrapulmonary as well as extrapulmonary affectation (15.34%). TB was diagnosed at the same time that a disease which met AIDS criteria in 13.49% of cases, TB was diagnosed first in 32.55% of cases, and AIDS was diagnosed before TB in only 7.91% of cases. Fever was the predominant symptom (88.84%), together with toxic status at admittance (80.47%) and deteriorated immune situation with lymphocytes count decrease (mean 1240/mm) and CD4 (mean value 134.5/mm) together with a mean raised IgA (492.85 mg/dl). Thorax radiography was normal in 34.88%. In 33 of these patients TB was localized in the lung, in 27.91% primary radiologic types were observed while in 31.16% reactivation types. In 51 cases (23.72%) tuberculosis was detected in patients (DAP) who were forwarded from the penitentiary system.(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS-Related Opportunistic Infections↗
PubMed1992

Transient global amnesia after cerebral angiography with iohexol.

We describe a patient without a previous history of migraine or epilepsy and with no known vascular risk factors, who suffered subarachnoid haemorrhage. During vertebral angiography using nonionic contrast medium (iohexol), spasm of the basilar artery was seen. The patient suffered transient global amnesia. Angiography 3 months later with the same contrast medium was normal and produced no further deficit. This case lends support to the supposed ischaemic aetiology of transient global amnesia; in patients without other evidence of cerebrovascular disease, arterial spasm may be responsible.

Amnesia, Retrograde↗
PubMed1992

Early changes of urinary amylase isoenzymes in diabetes mellitus.

The altered excretion of isoenzymes of amylase in urine was used as an early indicator of the loss of electric charges in the glomerular basement membrane, in 202 juvenile-onset insulin-dependent diabetic patients, compared with the pattern of excretion in 51 normal subjects matched for age and sex. Diabetics showed an increased excretion of salivary amylase. The salivary to pancreatic amylase ratio in urine (S/P ratio) was always below 1 in control subjects, but was elevated in 33.2% of diabetics, although microalbuminuria was present in only 26.2% of diabetic patients. The concentrations of other proteins in urine were within the reference ranges in nearly all patients, indicating that the kidney was not seriously affected. The increased salivary amylase excretion was not due to changes in the plasma concentration of any of the isoamylases, but to a real increase in excretion, as its fractional excretion in relation to creatinine clearance was clearly increased (1.0 +/- 0.7 vs. 1.52 +/- 1.99, p < 0.05), and the ratio of their clearances was also increased (0.35 +/- 0.18 vs. 0.49 +/- 0.61, p > 0.05). Moreover, the prevalence of altered S/P ratios was higher than the prevalence of microalbuminuria (36.6% vs. 18.8% of patients in the first decade of evolution of insulin-dependent diabetes mellitus). Altered S/P ratios were most prevalent in the first decade, whereas microalbuminuria was most prevalent in the second decade of the disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Utility of filtration markers to monitor the quality of glomerular function.

Diabetes mellitus can lead, along the years of its course, to chronic renal failure in a high proportion of cases. An early risk-indicator of later diabetic nephropathy is the presence of microalbuminuria, but it usually takes about fifteen to twenty years to appear. Before that, no clinical signs can disclose the underlying alterations of glomerular basement membrane that will eventually bring forth overt nephropathy. The usefulness of the altered excretion of isoenzymes of amylase as an early marker of the glomerular charge selectivity was tested in 202 juvenile onset insulin-dependent diabetics, compared with 51 normal subjects matched for age and sex. The diabetic patients studied showed increased excretion of salivary amylase into urine. The salivary to pancreatic amylase ratio of concentrations in urine was always below 1 in normal subjects, and was increased over 1 in 33.2% of diabetics, although microalbuminuria was present only in 26.2% of patients. The excretion of other proteins was within reference values in the majority of cases, indicating that the kidney was not seriously affected in those patients. Moreover, the altered salivary to pancreatic amylase ratio in urine was more prevalent than microalbuminuria (36.6% vs 18%) in the first decade of the evolution of the diabetes. These results indicate that the ratio of excretions of both isoamylases into urine is a more sensible and earlier marker of altered glomerular charge barrier for anionic proteins.

Adult↗
PubMed1992

[Pneumocystis carinii pneumonia in AIDS and prolonged fever].

Pneumonia by Pneumocystis carinii (NPC) presents a high incidence in the evolution of patients infected by the human immunodeficiency virus (HIV). Common clinical signs include fever, dry cough and dyspnea, in the presence of pulmonar interstitial affection with several degrees of hypoxemia. One hundred and sixteen patients with NPC and infection by HIV were diagnosed between December 1986 and January 1990. Criteria of persistent fever was established in 10 of them (8.7%), with normal thoracic radiography at the time of hospitalization. NPC in the adquired immunodeficiency syndrome (SIDA) may develop' with persistent fever, joining the large relation of entities manifesting in this way.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Inhibition of murine monocyte proliferation by a colony-stimulating factor-1 antisense oligodeoxynucleotide. Evidence for autocrine regulation.

Using a combination of v-myc and v-ras oncogenes, we have established a growth factor-independent monocyte cell line from murine fetal liver (FL-ras/myc). Biologic and molecular characterization demonstrated that the gene for the macrophage growth factor CSF-1 and the c-fms proto-oncogene (CSF-1 receptor) are expressed in this cell line, thus suggesting autocrine regulation as a possible mechanism for the unregulated growth of these cells. To study this possibility, we used 1) mAb, to neutralize the CSF-1 protein produced by the cell line, and 2) antisense oligomers, to inhibit CSF-1 gene products by specific base-pairing of complementary nucleic acids. We report here that both approaches inhibited in vitro cell growth by 60 to 70%, whereas the combination of oligomer and mAb inhibited proliferation by 95%. However, control antisense oligomers (50% bp mismatch with CSF-1 mRNA) did not inhibit FL-ras/myc cell growth. Furthermore, the inhibitory effects of mAb and oligomers were reversible when they were removed from the media. Detection of cell-associated CSF-1 protein by immunofluorescence showed that cells treated with the antisense oligomer expressed significantly less CSF-1 protein. These results indicate that the FL-ras/myc cell line requires CSF-1 for autonomous growth and that oligomers can efficiently block production of autocrine growth factors.

Animals↗
PubMed1990

Distribution of extracutaneous melanin pigment in Sparus auratus, Mugil cephalus, and Dicertranchus labrax (Pisces, Teleostei).

The morphological and biochemical characteristics of pigment accumulations found in the kidney, liver, spleen, and mesentery of three different species of teleost fishes have been studied. There are significant differences in number, distribution, and morphology of pigment accumulations in different organs of the three species. Biochemical studies have shown the existence of tyrosinase activity in the mesentery of Mugil cephalus and in the kidney and mesentery of Sparus auratus. No tyrosinase activity was found in any internal organs of Dicertranchus labrax. That activity was assayed using three methods: tyrosine hidroxylation, dopa oxidation, and melanin formation. The morphological and biochemical observations are in agreement. In those organs in which we have demonstrated melanin synthetic activity, the pigment cells are morphologically and like melanophores, while in the organs that show no melanin synthetic activity, the pigment cells resemble macrophages.

Animals↗
PubMed1989

Haemopoiesis in the head kidney of Sparus auratus.

The haemopoiesis of Sparus auratus is formed by the following series: erythro-thrombopoietic, granulopoietic, lymphoplasmapoietic and monocytes. All the cells which form these series originate from one cell called the stem-cell, there being a network of reticular cells and melanomacrophage centres amongst these cells. The erythropoietic series comprises erythroblast, proerythrocytes, polychromatocytes, reticulocytes and erythrocytes. The morphological changes which occur during the maturing process are: heterochromatinization of the nuclei, the gradual decrease of organelles in the cytoplasm and the increase of the haemoglobin. We also observed thrombocytes characterized by the presence of numerous vacuoles and abundant glycogen in the cytoplasm. In the lymphoplasmapoietic series are seen lymphoblasts, lymphocytes and plasma cells. The lymphocytes are cells of different sizes with small microvilli in the cell surface and scanty cytoplasm. Outstanding in the plasma cell is the well developed granular endoplasmic reticulum. The monocytes are large cells with an indented nucleus and cytoplasm containing numerous vesicles of different sizes and also a few lysosomes.

Animals↗
PubMed1988

Granulopoiesis in the head kidney of Sparus auratus.

The head kidney of Sparus auratus (teleost) is comprised of erythropoietic, granulopoietic and lymphopoietic cells. This study describes the ultrastructure of the granulopoietic series of cells. Heterophils, eosinophils and basophils were found at various stages of development. The most numerous cells are the neutrophils, the cells of the basophilic series being very scarce. The most outstanding characteristics of the neutrophil series are the eccentric and slightly segmented nucleus and cytoplasm with numerous, homogeneously dense granules. The eosinophils show a lobed nucleus and two types of granules in the cytoplasm. In the basophils, the cytoplasmic granules are large with fibrillar contents.

Animals↗
PubMed1987

Ultrastructure of the tubular nephron of Testudo graeca (Chelonia). A comparison between hibernating and non-hibernating animals.

The tubular nephron of hibernating and non-hibernating specimens of Testudo graeca (Chelonia) was studied by means of conventional light and electron microscopy and histochemistry. The tubular nephron was composed of proximal, intermediate, distal and collecting tubules in both hibernating and non-hibernating animals. The cells of the proximal tubule showed long microvilli, cytoplasmic vacuoles, a developed endoplasmic reticulum and abundant mitochondria. Fat droplets were also observed. The intermediate segment was lined by ciliated and non-ciliated cells. The lining cells of the distal tubule presented few microvilli, abundant dense mitochondria and clear vesicles of mucous appearance in the terminal portion. Collecting ducts are composed of mucous and non-mucous cells. Mucous cells presented strong reaction to the histochemical techniques detecting sialo- and sulpho-mucins. During hibernation, a progressive vacuolar degeneration of the endoplasmic reticulum was observed in all the segments of tubular nephron, which may be caused by a massive intake of extracellular water into the cell.

Animals↗
PubMed1987

A microscopic study of the tracheal epithelium of Testudo graeca and Pseudemys scripta elegans.

The tracheal epithelium of Testudo graeca and Pseudemys scripta elegans was studied by means of light and electron microscopy, histochemistry and immunocytochemistry. Three cell types were detected by conventional light microscopy: mucous, ciliated and basal. The Grimelius silver argyrophil technique was positive in a population of tracheal cells. By immunocytochemistry, serotonin-containing cells were identified. The mucous cells of Testudo graeca contained sialomucins and sulphomucins; however, only sialomucins were detected in Pseudemys scripta elegans. By electron microscopy four cell types were observed: mucous, ciliated, basal and endocrine. Plasma cells were also found. The differences between the species studied lay mainly in the ultrastructure of the ciliated cells, the mucous granules and the presence of a special type of basal cell called 'clear basal cells' in non-hibernating specimens of Testudo graeca. During hibernation, the tracheal epithelium of Testudo graeca showed the following changes: (1) Myelin bodies were present in the cytoplasm. (2) The intercellular spaces were remarkably widened. (3) No 'clear basal cells' were present. In conclusion, the tracheal epithelium of the reptiles studied showed a pattern similar to that described in mammals but some differences from reptiles previously studied were found.

Animals↗
PubMed1987

The liver of Testudo graeca (Chelonia). A comparative study of hibernating and non-hibernating animals.

In the present work, a comparative study of the liver of hibernating and non-hibernating specimens of Testudo graeca (Chelonia) has been carried out by light and electron microscopy. During hibernation, the morphological changes which take place do not affect the general architecture of the liver, but are mainly concerned with the number and distribution of the cytoplasmic organelles and reserve materials in the hepatocytes. In non-hibernating animals, the cytoplasm of the hepatocytes has a large number of organelles indicating a high cell activity, as well as numerous lipid droplets and glycogen. In hibernating animals, the size of the hepatocytes is reduced and the cytoplasm is vacuolated. There is also an increase in lysosomal activity due to the increase in the number of secondary lysosomes in the cytoplasm. Sacs full of degenerating hepatocytes can be observed among the hepatic cells. Glycogen and lipid droplets are not present in the hibernating animals. The present study demonstrates that, during hibernation, the hepatocytes likely undergo ultrastructural changes related to the synthesis, storage and release of reserve material.

Animals↗
PubMed1986

Ultrastructure of the renal corpuscle of Testudo graeca (Chelonia). A comparison between hibernating and non-hibernating animals.

The renal corpuscle of hibernating and non-hibernating Testudo graeca was studied by means of light and electron microscopy. Renal corpuscles are small and have a glomerular architecture similar to that found in other vertebrates with a limited glomerular filtration rate. In hibernating animals, unlike non-hibernating, some morphological changes took place. The cells of the renal corpuscle were densely packed, podocytes and parietal cells showed a marked cytoplasmic vacuolization, there was a highly developed capillary basement membrane and the endothelial and mesangial cells showed abundant dense granules. These morphological features apparently correspond to a vacuolar degeneration. They may also be the morphological basis of the decrease in the glomerular filtration rate observed during this period.

Animals↗
PubMedDate not supplied

Occurrence of melanin granules and melanosynthesis in the kidney of Sparus auratus.

An optical, ultrastructural, and biochemical study of the melanin accumulation nodules found in the kidney of the teleost fish Sparus auratus is presented. These nodules are randomly distributed in the interstitium of the renal tissue. They are formed by large aggregates of cells replete with melanin granules. The melanin granules occur singly or also in aggregates inside the cells. Most of the granules are electron-dense, but sometimes small electron-lucent spaces within them can be seen. Some secondary lysosomes and dendritic processes can also be observed. Biochemical studies have proved for the first time the existence of measurable tyrosinase activity in those nodules. That activity was assayed using three methods: tyrosine hydroxylation, dopa oxidation, and melanin formation. Furthermore, inhibitors of well-characterized plant and animal skin tyrosinases were effective agents for inhibiting those activities in fish kidney preparations. This finding supports the notion of the existence of true tyrosinase in the melanin accumulation nodules of this tissue. Taking into account the results obtained, the origin and functions of the melanin-containing cells found in the teleost fish kidney are discussed.

Animals↗