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Biomedical subjects

L Ramos

Publications and source records attributed to L Ramos.

At least 109 records · Page 6Linked to original sources

[Qualitative and quantitative variations in carotenoid pigments in the ovary and hepatopancreas of Penaeus schmitti during ovarian maturation].

Carotenoid pigments of Penaeus schmitti were investigated and identified in the ovaries and hepatopancreas. Their individual variations were measured in these two organs. The relative concentrations of zeaxanthin in hepatopancreas and astaxanthin in ovaries increased during the sexual development. The role of zeaxanthin monoester in carotenoids transfer from hepatopancreas to ovaries during this sexual development is discussed.

Animals↗

[Variations in protein levels in the hemolymph, hepatopancreas and ovary of Penaeus schmitti during ovarian maturation (Crustacea, Decapoda, Peneidae)].

Variations of protein concentrations in the haemolymph, hepatopancreas and ovaries were studied during the ovarian maturation of the shrimp Penaeus schmitti. The main variations observed during this physiological process are the increase of protein and the decrease of water contents in the ovary, more pronounced at the first stages of gonadosomatic index (GSI:0-4). During ovarian maturation, water content of the ovaries and hepatopancreas decrease from 10.7 and 3.9% respectively. In relative values, protein content increases from about 40.0% in the ovary, 47.5% in the haemolymph and 15.4% in the hepatopancreas. In absolute values, the protein concentrations of the hepatopancreas showed no significant variation. In the opposite, ovary protein content is 14.7 fold higher at the end than the early stages of vitellogenesis. Relations between haemolymph, hepatopancreas and ovary with eventual transfers of protein material are discussed.

Animals↗

Histamine-induced suppressor macrophage inhibits fibroblast growth and wound healing.

To determine whether there is histamine-induced suppressor activity in macrophage-related functions other than in immunity, extracts and media from a macrophage cell line, RAW 264, were tested for suppressor effect on fibroplasia. The procedure consisted of priming confluent RAW 264 cells in culture with media or cellular extracts of washed mastocytes (P-815). The inoculum was removed from the RAW 264 cells by rinsing with fresh medium 24 hours later, and then with medium replacement and 3 more days of culture. The culture media or extracts of washed RAW 264 cells were tested for suppressor activity. The primed RAW 264 cells were lysed by 4 freeze-thaw cycles and cleared by centrifugation, and the resulting supernatant was tested on fibroblast (3T3) cell growth and wound healing in mice and for suppressor activity on T cells. Replication of 3T3 cells, as quantitated by uptake of [3H]thymidine, was reduced 75% when "suppressor" material from RAW 264 cells was added to 3T3 cultures and not when media or extracts of unprimed RAW 264 cells were added. Tensiometric measurements of wound breaking strength (full-thickness incised wounds) were reduced 31% by day 4 and 47% by postsurgical day 7 when "suppressor" RAW 264 extracts were instilled into wounds. Leukocyte cultures stimulated with phytohemagglutinin had a reduced uptake of [3H]thymidine (suppressed 90% to 95%) when exposed to primed RAW 264 extracts, whereas kidney cell culture lines were unaffected. The data obtained indicated that mastocyte (histamine)-induced suppressor factors are present for fibroblast activity as well as T-cell function.

Animals↗

Characterization of deoxyribonucleic acid from cells infected with Aleutian disease virus.

Viral DNA was extracted from Crandell feline kidney (CRFK) cells infected with Aleutian disease virus (ADV) and labeled with [ 3H ]thymidine. The sedimentation coefficient in alkaline sucrose gradients was 16S corresponding to a molecular weight of 1.5 X 10(6). The buoyant densities of DNA from infected and control cells were determined by isopyknic sedimentation in CsCl and NaI gradients. Two additional peaks of [ 3H ]DNA were found in infected cells, but not in control cell extracts. Fractionation of this DNA on hydroxylapatite indicated that the new peaks represented a single-stranded component, density 1.728 g/cm3, and a double-stranded component, presumed to be a viral replicative intermediate, density 1.718 g/cm3. The target antigen formation in CRFK cells was measured by gamma-irradiation of ADV and assayed for focus formation. The calculated size of ADV based on these measurements was 1.1 X 10(6). The H-1 parvovirus also was shown to have a size of 1.5 X 10(6) daltons for both antigen and plaque formation. The data indicated similarities existed between ADV and other autonomously replicating parvoviruses in most properties, except that less-than-unit length genome of ADV may be transcribed.

Aleutian Mink Disease Virus↗

Radiological characteristics of primary intestinal lymphoma of the "Mediterranean" type: observations on twelve cases.

Radiological findings in 12 cases of "Mediterranean" lymphoma are analyzed, 4 of which are associated with gammapathy. These findings have not permitted differentiation of this type of lymphoma from those classically described, although there are two signs that strongly suggest this diagnosis: extension of the lesions along wide areas of the small intestine, almost always including the duodenum, and spiculation of the mucosal fold edges, representing massive plasmocyte infiltration of the lamina propria. The principal clinical, immunological, and pathological aspects are described, as well as the radiological differential diagnosis.

Adult↗

Properties of Aleutian disease virus assayed with feline kidney cells.

Properties of Aleutian disease virus (ADV) were studied using feline kidney cells, line CRFK, to assay virus by the induction of nuclear antigen. ADV nuclear antigen was detected by immunofluorescent staining. Titers of virus obtained from mink spleens at 10-8 days after infection were usually between 10(3) and 10(5) infectious units per gram of spleen. ADV was purified by fluorocarbon extraction, differential centrifugation, biogel A-15 chromatography and CsCl equilibrium centrifugation. The molecular weight of the virus was estimated to be 3-5 X 10(5) daltons. The density of antigen-inducing virus in equilibrium CsCl gradients was 1.32--1.34 g/cm3. On velocity sucrose gradients, antigen-inducing virus had a sedimentation coefficient of approximately 110S. The virus was not neutralized by sera from chronically infected mink and ferrets and by sera from experimentally infected mink. ADV was resistant to ionic and nonionic detergents and lipid solvents. The titer of partially purified virus was reduced as much as 700-fold by proteolytic enzymes but not by DNase or RNase. The virus was inactivated slowly at 56 degrees C; the initial half-life was 90 minutes. It is concluded that the properties of ADV can be determined by assay in CRFK cells, thus facilitating virological study of the disease.

Aleutian Mink Disease Virus↗

Adrenal cysts: diagnostic value of "intravenous viscerogram".

Two cases of adrenal pseudocysts are presented, one secondary to the necrosis of an adenoma and the other a hemorrhagic pseudocyst. The diagnosis of these tumors is usually made radiologically owing to the vagueness of symptoms and nonexistent specific laboratory examinations, so that preoperative diagnosis is uncommon. We present a radiologic technique, intravenous viscerogram, which may be useful in the diagnosis of adrenal cysts. This procedure is easy to carry out and has almost no complications for the patient. The classification, clinical findings, and surgical treatment of adrenal cysts are discussed.

Adrenal Gland Diseases↗

Lymphoproliferative diseases of fowl: JM-V leukemic lymphoblasts in cell culture.

JM-V leukemic lymphoblasts were established in cell culture. The cultured cells (JM-VLC cells) were transplantable in young chicks and produced a disease indistinguishable from JM-V lymphoblastic leukemia as initiated by whole-blood inoculation. JM-VLC cells maintained a normal female karyotype through 13 passages in Rhode Island Red cockerels. With the use of JM-V antisera and antisera from birds with naturally occurring Marek's disease (MD), specific antigens were detected on the surfaces of living cells. Intracellular antigens were detected with anti-MD virus sera after cultivation for at least 1 day at 37 degrees C. In spite of the expression of MD antigens, the presence of herpesvirus particles associated with the cultured cells, and the occurrence of foci of multinucleated cells in kidney cultures from chicks inoculated with cellfree preparations of JM-VLC cells, the pathologic potential of the cultured cells was that of JM-V leukemia.

Animals↗

Expression of Aleutian mink disease antigen in cell culture.

Infection of CRFK feline kidney cells with Aleutian disease vurus leads to production of virus-induced antigen(s) in the nucleus which could be demonstrated by the fluorescent-antibody technique. The number of fluorescent nuclei was lineraly dependent on the dilution of the inoculum, but rarely exceeded 20% of the cells. Aleutian disease nuclear antigen was only transiently detectable. The virus-induced antigen was detected after infection of cells of several divergent species; however, the CRFK line of feline kidney cells was the most susceptible. Inhibitor studies indicated that deoxyribonucleic acid synthesis, ribonucleic acid synthesis, and protein synthesis were required for viral antigen production. Cell growth was also a requirement for synthesis of viral antigen, An in situ radioimmune assay was used to measure binding of 125I-labeled mink anti-Aleutian disease virus to infected cells and competition with unlabeled sera. The system is suitable for quantitation of infectivity.

Aleutian Mink Disease↗

[Value of the technique of intravenous infusion of contrast media for the diagnosis of fluid processes (author's transl)].

The study covered 50 patients suffering from hepatic effusions; a solution used in contrast intravenous psychography was administered to them by the intravenous route, at similar doses to those used in intravenous psychography with infusions. This process which we have called Intravenous Viscerogramme, because of the similarity of the images obtained with those of the viscerographic phase of arteriography, has enabled the diagnosis of 35 hydatidiform cysts, one case of cholangiolar hamartoma and an abscess. Owing to the ease with which it can be carried out, we think that it can be used in the diagnosis of tumoral lesions of the liver. When the result is positive, radiological signs are obtained which enable identification of the lesion, thus avoiding resorting to more complex investigations such as angiography.

Humans↗

Radiological characteristics of perforated pulmonary hydatid cysts.

Perforation of pulmonary hydatid cysts into the bronchial tree was seen in 56 of 239 cases. The resulting radiological signs are much more specific than those seen prior to perforation. These signs are described and correlated with the cystic structures that give rise to them. Perforation into the pleural cavity, seen in 5 cases, may result in secondary hydatidosis, as happened in one case.

Echinococcosis↗