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1.
s.l; The National medical journal of India; 2017. 4 p.
Monography in English | PIE | ID: biblio-1008324

ABSTRACT

Equity in health and equitable access to healthcare has been at the core of health policy in India. The key policy challenge has been how to make that possible? Various health insurance schemes such as the Rashtriya Swasthya Bima Yojana and Arogyasri seek to improve poor people's access to specialist medical care in the public and private sectors. On the other hand, access to primary medical care has been left to the supply side interventions.


Subject(s)
Humans , Comprehensive Health Care/economics , Comprehensive Health Care/methods , Healthcare Disparities/economics , Health Policy, Planning and Management/economics , India
2.
Phys Rev Lett ; 114(3): 037001, 2015 Jan 23.
Article in English | MEDLINE | ID: mdl-25659014

ABSTRACT

We show that a small number of intentionally introduced defects can be used as a spectroscopic tool to amplify quasiparticle interference in 2H-NbSe2 that we measure by scanning tunneling spectroscopic imaging. We show, from the momentum and energy dependence of the quasiparticle interference, that Fermi surface nesting is inconsequential to charge density wave formation in 2H-NbSe2. We demonstrate that, by combining quasiparticle interference data with additional knowledge of the quasiparticle band structure from angle resolved photoemission measurements, one can extract the wave vector and energy dependence of the important electronic scattering processes thereby obtaining direct information both about the fermiology and the interactions. In 2H-NbSe2, we use this combination to confirm that the important near-Fermi-surface electronic physics is dominated by the coupling of the quasiparticles to soft mode phonons at a wave vector different from the charge density wave ordering wave vector.

3.
Immunogenetics ; 66(6): 393-402, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24752816

ABSTRACT

The relationship between invaders and the pathogens encountered in their new environment can have a large effect on invasion success. Invaders can become free from their natural pathogens and reallocate costly immune resources to growth and reproduction, thereby increasing invasion success. Release from enemies and relaxation of selective pressures could render newly founded populations more variable at immune-related genes, such as the major histocompatibility complex (MHC), particularly when they have different origins. Using rainbow and brown trout, two of the world's most successful fish invaders, we tested the general hypothesis that invaders should display high intrapopulation immunogenetic diversity and interpopulation divergence, due to the interplay between genetic drift and successive waves of genetically divergent introductions. We analysed genetic diversity and signatures of selection at the MHC class II ß immune-related locus. In both species, MHC diversity (allelic richness and heterozygosity) for southern hemisphere populations was similar to values reported for populations at their native range. However, MHC functional diversity was limited, and population immunogenetic structuring weaker than that observed using neutral markers. Depleted MHC functional diversity could reflect a decrease in immune response, immune-related assortative mating or selection for resistance to newly encountered parasites. Given that the role of MHC diversity in the survival of these populations remains unclear, depleted functional diversity of invasive salmonids could compromise their long-term persistence. A better understanding of the eco-immunology of invaders may help in managing and preventing the impact of biological invasions, a major cause of loss of biodiversity worldwide.


Subject(s)
Genetic Variation , Histocompatibility Antigens Class II/genetics , Oncorhynchus mykiss/genetics , Phylogeny , Alleles , Animals , Chile , Ecosystem , Falkland Islands , Gene Frequency , Genetic Drift , Histocompatibility Antigens Class II/classification , Histocompatibility Antigens Class II/immunology , Introduced Species , Oncorhynchus mykiss/immunology , Phylogeography , Selection, Genetic
4.
J R Soc Interface ; 9(73): 1725-32, 2012 Aug 07.
Article in English | MEDLINE | ID: mdl-22319111

ABSTRACT

For many species, there is broad-scale dispersal of juvenile stages and/or long-distance migration of individuals and hence the processes that drive these various wide-ranging movements have important life-history consequences. Sea turtles are one of these paradigmatic long-distance travellers, with hatchlings thought to be dispersed by ocean currents and adults often shuttling between distant breeding and foraging grounds. Here, we use multi-disciplinary oceanographic, atmospheric and genetic mixed stock analyses to show that juvenile turtles are encountered 'downstream' at sites predicted by currents. However, in some cases, unusual occurrences of juveniles are more readily explained by storm events and we show that juvenile turtles may be displaced thousands of kilometres from their expected dispersal based on prevailing ocean currents. As such, storms may be a route by which unexpected areas are encountered by juveniles which may in turn shape adult migrations. Increased stormy weather predicted under climate change scenarios suggests an increasing role of storms in dispersal of sea turtles and other marine groups with life-stages near the ocean surface.


Subject(s)
DNA, Mitochondrial/genetics , Phylogeography/methods , Turtles/physiology , Animals , Cyclonic Storms , Female , Male , Oceanography/methods , Oceans and Seas
5.
s.l; PAHO; 2012. 9 p.
Monography in English | PIE | ID: biblio-1007231

ABSTRACT

A rare disease is a disease that occurs infrequently or rarely in the general population. In order to be considered as rare, each specific disease cannot affect more than a limited number of people out of the whole population, defined in Chile as 0.18 in 10,000 citizens (Minister of Health draft of the law on rare diseases). This figure can also be expressed as 18 patients with rare diseases out of 1 million citizens. While 0.18 out of 10,000 seems very few, in a total population of 17 million citizens this could mean as many as 306 individuals for each rare disease. It is important to underline that the number of patients with rare disease varies considerably from disease to disease, and that most people represented by the statistics in this field suffer from even rarer diseases, affecting only one in 100,000 people or less. Some rare diseases do only affect a couple of dozens patients. These very rare diseases make patients and their families particularly isolated and vulnerable.


Subject(s)
Humans , Health Systems/organization & administration , Rare Diseases/therapy , Chile
6.
Phys Rev Lett ; 107(20): 207207, 2011 Nov 11.
Article in English | MEDLINE | ID: mdl-22181768

ABSTRACT

Theory predicts the low temperature magnetic excitations in spin ices consist of deconfined magnetic charges, or monopoles. A recent transverse-field (TF) muon spin rotation (µSR) experiment [S. T. Bramwell et al., Nature (London) 461, 956 (2009)] reports results claiming to be consistent with the temperature and magnetic field dependence anticipated for monopole nucleation-the so-called second Wien effect. We demonstrate via a new series of µSR experiments in Dy(2)Ti(2)O(7) that such an effect is not observable in a TF µSR experiment. Rather, as found in many highly frustrated magnetic materials, we observe spin fluctuations which become temperature independent at low temperatures, behavior which dominates over any possible signature of thermally nucleated monopole excitations.

7.
Nat Commun ; 2: 422, 2011 Aug 09.
Article in English | MEDLINE | ID: mdl-21829184

ABSTRACT

In a prototypical ferromagnet (Ga,Mn)As based on a III-V semiconductor, substitution of divalent Mn atoms into trivalent Ga sites leads to severely limited chemical solubility and metastable specimens available only as thin films. The doping of hole carriers via (Ga,Mn) substitution also prohibits electron doping. To overcome these difficulties, Masek et al. theoretically proposed systems based on a I-II-V semiconductor LiZnAs, where isovalent (Zn,Mn) substitution is decoupled from carrier doping with excess/deficient Li concentrations. Here we show successful synthesis of Li(1+y)(Zn(1-x)Mn(x))As in bulk materials. Ferromagnetism with a critical temperature of up to 50 K is observed in nominally Li-excess (y=0.05-0.2) compounds with Mn concentrations of x=0.02-0.15, which have p-type metallic carriers. This is presumably due to excess Li in substitutional Zn sites. Semiconducting LiZnAs, ferromagnetic Li(Zn,Mn)As, antiferromagnetic LiMnAs, and superconducting LiFeAs systems share square lattice As layers, which may enable development of novel junction devices in the future.

8.
Santiago; Evidence-Informed Policy Network (EVIPNet); 2011. 41 p.
Monography in English | PIE | ID: biblio-1007148
9.
Med. segur. trab ; 53(209): 57-63, dic. 2007. ilus, tab
Article in Es | IBECS | ID: ibc-67617

ABSTRACT

La vacunación antigripal es la medida más eficazpara prevenir la gripe. Dentro de los colectivos laborales en los que se recomienda su inoculación, seencuentran los trabajadores sanitarios.Objetivos:, Estudiar si existen diferencias significativas entre las Campañas del 2005-06 y 2006-07dirigidas a los trabajadores del área sanitaria 2 de laComunidad de Madrid.Metodología: Estudio descriptivo de ambas campañasen el área sanitaria 2 de la Comunidad de Madrid. Se realiza un análisis univariante y se construye un modelo de Regresión Logística cuya variable dependiente son las dos campañas. Comovariables independientes se incluyeron: edad, categoría, servicio, centro de trabajo, vacunación de la gripe en el año anterior, efectos secundarios en año el anterior, enfermedad crónica, medicación, fumador y procesos alérgicos.Resultado:. En la Campaña 2005 se vacunaron más en servicios centrales, hostelería y administración.Se declararon más efectos secundarios, se vacunaron más sanitarios y más trabajadores declararon tomar algún tipo de medicación. Sin embargo en la Campaña 2006 se vacunaron más en el H. U. Princesa, en la primera semana de campaña, en los servicios médicos y más trabajadores declararon tener algún tipo de enfermedad crónica.Conclusiones: Las coberturas vacunales han sidoiguales o inferiores a años anteriores en los distintoscentros excepto en el Hospital U. de la Princesadonde fue mayor


The vaccination against the influenza is the mosteffective way of preventing this illness. Workers inthe Sanitary sector are ones of the most recommendedto be vaccinated against the flu.Objectives: To study whether there are significantdifferences between the 2005-2006 and 2006-2007Campaigns addressed to the workers in the Sanitaryarea nº 2 in the Madrid Community.Methodology: Descriptive study of both campaignsin the Sanitary area nº 2 in the Madrid Community.A uni-variant analysis is carried out to builda Logistic Regression model in which the two campaignsare the dependant variables. The followingindependent variables were also included: age, professional category, service, working center, previousyear anti-flu vaccination, side effects in previousyear, chronic diseases, medication taken, smokinghabits and allergic processes.Results: In the 2005 campaign, vaccination wasmore intense in central services, catering and administration. There were more side effects, more sanitary workers were vaccinated and more workersdeclared to have taken any sort of medication. However,in the 2006 campaign there were more vaccinationsin the “H.U. la Princesa”, within the first weekof campaign, in the medical services, and more workersdeclared to suffer any type of chronic disease.Conclusions: The coverage of the vaccination hasbeen equal or lower than in previous years in all workingcenters, with the exception of the “H.U. la Princesa”,where the coverage was higher


Subject(s)
Humans , Influenza Vaccines/administration & dosage , Influenza, Human/prevention & control , Influenza, Human/epidemiology , Occupational Health Services/organization & administration , Mass Vaccination/statistics & numerical data , Evaluation of Results of Preventive Actions
10.
Rev. costarric. cardiol ; 7(2): 21-23, mayo-ago. 2005. ilus
Article in Spanish | LILACS | ID: lil-580843

ABSTRACT

Niño de 11 años de edad con historia de dolor torácico intermitente de 6 meses de evolución y soplo cardíaco. El ecocardiograma mostró una masa tumoral en la válvula mitral con insuficiencia valvular moderada. Se intervino quirúrgicamente con resección extensa del tumor de la válvula mitral y de los músculos papilares al cual estaba adherido, se colocó una válvula mitral protésica. El diagnóstico patológico fue de mixoma de la válvula mitral. Este tumor es raro en la infancia, con una localización pocas veces descrita, de carácter benigno, pero potencialmente fatal.


Subject(s)
Humans , Male , Child , Myxoma , Neoplasms , Mitral Valve/surgery
11.
Rev. costarric. cardiol ; 7(1): 47-49, ene.-abr. 2005. ilus
Article in Spanish | LILACS | ID: lil-432908

ABSTRACT

Niño con 26 días de edad al ingreso, presentó cianosis y dificultad respiratoria progresiva desde el nacimiento, se diagnosticó por ecocardiografía un tumor intracardíaco de la pared libre ventricular izquierda con derrame pericárdico leve. Durante la cirugía se encontró un tumor no resecable. El examen histológico lo clasificó como un fibroma. La mortalidad por fibromas cardíacos grandes es alta un disgnóstico temprano y una extirpación del tumor es mandatoria para aliviar la sintomatología y las consecuencias fatales, existen múltiples abordajes quirúrgicos para niños con fibromas cardíacos que van desde tomar la biopsia y esperar, hasta la resección parcial, total o incluso el trasplante cardíaco. Palabras clave: tumor cardíaco, fibroma, cirugía.


Subject(s)
Male , Humans , Infant, Newborn , Fibroma , Furosemide , Heart Neoplasms/diagnosis , Costa Rica
12.
J Submicrosc Cytol Pathol ; 36(1): 77-83, 2004 Jan.
Article in English | MEDLINE | ID: mdl-15311677

ABSTRACT

The in vitro cytopathic effect of four strains of Trichomonas vaginalis on cultured epithelial monolayers was analyzed through electrophysiology and electron microscopy. Interaction of trichomonads of two virulent strains (GT-10 and GT-13) with cultured MDCK cell monolayers mounted in Ussing chambers produced a rapid decrease in transepithelial resistance to less than 30% of control values after only 15 min. By 30 min the electrical resistance was practically abolished by the virulent parasites. In contrast, of two attenuated strains of trichomonads (GT-3 and GT-7) analyzed under similar conditions, GT-3 trophozoites required 180 min to reduce transepithelial resistance to 9% of control values, while monolayers in contact with GT-7 parasites still showed 28% of control values at this time of incubation. Sequential scanning electron microscopy confirmed the much faster and widespread cytopathic effect of virulent parasites. In contrast, the slow lytic process produced by attenuated trophozoites was reduced to focal areas of direct contact with epithelial cells. Another difference was found by measurement of the surface charge of the four strains of T. vaginalis by means of cell microelectrophoresis. While the two virulent strains showed a negative surface charge, the two attenuated strains had no detectable surface charge at neutral pH. When parasites were incubated with cationized ferritin and studied with transmission electron microscopy the surface of virulent trichomonads appeared heavily labeled, whereas the surface of attenuated parasites had only sparse and irregular ferritin binding.


Subject(s)
Cell Surface Extensions/ultrastructure , Surface Properties , Trichomonas vaginalis/pathogenicity , Trichomonas vaginalis/ultrastructure , Virulence Factors , Animals , Cell Line , Electric Impedance , Electrophoresis , Electrophysiology , Female , Humans , Mice , Microscopy, Electron, Scanning , Species Specificity , Trichomonas Vaginitis/parasitology , Trichomonas vaginalis/classification
13.
Am J Nephrol ; 20(3): 214-6, 2000.
Article in English | MEDLINE | ID: mdl-10878404

ABSTRACT

We present an unusual manifestation of tuberculosis in a patient on hemodialysis. A 73-year-old woman was admitted to our hospital with a picture of fever, dyspnea and weight loss. She had chronic renal failure and had started periodic hemodialysis 5 years before. Fifteen days after admission, she began with pancytopenia, abnormal liver function and coagulopathy. A bone marrow aspiration was made 1 week later showing macrophage elements with phagocytic activity. Eight weeks later, bone marrow culture in Lowenstein media confirmed the presence of tuberculosis. After the beginning of antituberculosis therapy, the laboratory disturbances disappeared and the clinical situation improved. We think that fever of unknown origin and pancytopenia in patients on maintenance hemodialysis must lead to an early bone marrow biopsy or aspiration since after the diagnosis a specific therapy can cure the disease.


Subject(s)
Histiocytosis, Non-Langerhans-Cell/etiology , Kidney Failure, Chronic/complications , Tuberculosis/complications , Aged , Antitubercular Agents/therapeutic use , Female , Humans , Kidney Failure, Chronic/therapy , Renal Dialysis , Tuberculosis/drug therapy
14.
Parasitol Res ; 86(2): 140-50, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10685845

ABSTRACT

Leishmania differentiates from the promastigote to the amastigote stage during its digenetic life cycle. Characterization of the developmentally regulated genes during that process would help to elucidate the mechanisms of gene regulation. In this study, specific fragments of mRNAs from the amastigote stage of L. mexicana mexicana were discriminated from those of the promastigote and metacyclic stages by differential display. This technique combined with spliced-leader polymerase chain reaction allowed isolation of the complete gene VG7A5. The sequence of this gene did not align with any published L. mexicana sequence. More than one copy of this gene was identified in the genome by Southern-blot analysis and was transcribed exclusively in the amastigote stage. At 20 bp upstream from the splice AG site it has a trans-splicing polypyrimidine tract. The gene encodes the subcellular localization motifs 5'-GGACT and AAGCT-3' in the 3' untranslated region of the mRNA. The open reading frame of the gene VG7A5 predicts a polypeptide of 587 amino acid residues that has a KGRR amidation motif near its carboxyl terminus, suggesting that in the mammalian host this protein may be involved in the process of acute inflammation.


Subject(s)
Gene Expression Regulation, Developmental , Genes, Protozoan , Leishmania mexicana/genetics , 5' Untranslated Regions , Amino Acid Sequence , Animals , Base Sequence , Cell Differentiation , Gene Dosage , Gene Expression Profiling , Gene Library , Molecular Sequence Data , Polymerase Chain Reaction
15.
J Eukaryot Microbiol ; 45(3): 265-72, 1998.
Article in English | MEDLINE | ID: mdl-9669863

ABSTRACT

The cytological features of Entamoeba dispar, recently recognized by biochemical and molecular biology criteria as a distinct species, were compared to those of Entamoeba histolytica When cultured under axenic conditions, living trophozoites of E. dispar strain SAW 76ORR clone A were more elongated in form, had a single frontal pseudopodium, and showed a noticeable uroid. In sections of E. dispar trophozoites stained with Toluidine blue, characteristic areas of cytoplasmic metachromasia were seen due to the presence of large deposits of glycogen, seldom found in E. histolytica strain HM1:IMSS. Under the light microscope the periphery of the nucleus in E. dispar was, lined by finer, more regularly distributed dense granules. With transmission electron microscopy the surface coat of E. dispar was noticeable thinner. In addition. E. dispar had a lower sensitivity to agglutinate with concanavalin A and a higher negative surface charge, measured by cellular microelectrophoresis. The cytopathic effect of E. dispar was much slower, analyzed by the gradual loss of transmural electrical resistance of MDCK epithelial cell monolayers mounted in Ussing chambers. Whereas in E. histolytica phagocytosis of epithelial cells plays an important role in its cytopathic effect. E. dispar trophozoites placed in contact with MDCK cells showed only rare evidence of phagocytosis. The results demonstrate that the morphology of E. dispar is different to that of E. histolytica, both at the light microscopical and the ultrastructural levels. In addition they show that E. dispar in axenic culture has a moderate cytopathic effect on epithelia] cell monoLayers. However, when compared to E. histolytica, the in vitro lytic capacity of E. dispar is much slower and less intense.


Subject(s)
Entamoeba/pathogenicity , Entamoeba/ultrastructure , Agglutination , Animals , Cell Line , Cell Membrane/ultrastructure , Cell Nucleus/ultrastructure , Concanavalin A , Cytoplasm/ultrastructure , Dogs , Electrophoresis , Entamoeba/chemistry , Entamoeba histolytica/chemistry , Entamoeba histolytica/pathogenicity , Entamoeba histolytica/ultrastructure , Microscopy, Electron , Microscopy, Electron, Scanning , Organelles/ultrastructure , Surface Properties
16.
J Submicrosc Cytol Pathol ; 30(1): 95-103, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9530857

ABSTRACT

During atrial septation, the septum primum fuses with the atrioventricular endocardial cushions and myocardial-mesenchymal interactions occur. In order to evaluate the cellular events that take place during this particular interaction a structural, ultrastructural and histochemical study was performed. Our findings indicate that from the fourth day of development, the distal myocardium of the interatrial septum, which interacts with mesenchymal tissue, loses its appearance of an epithelial sheet and becomes a loosely organized tissue. The distal myocytes of the interatrial septum which get progressively separated show features of migratory cells, the final localization of which is the mesenchymal tissue of the adjacent endocardial cushions. These tissue changes involve basal membrane disruption, reduction in the number of desmosomes and intercalated discs with the subsequent appearance of large intercellular spaces between myocytes, myofibrillar disarrangement and acquisition by myocytes of a secretory phenotype characterized by numerous cytoplasmic vesicles. These events occur in a similar way in the atrioventricular canal, where a myocardial-mesenchymal interaction also occurs. In both regions the mesenchymal endocardial cushions and its associated extracellular matrix seem to direct the dissociation of the myocardial tissue and the subsequent migratory cellular behaviour of the interacting myocytes. This is an interesting, and little known, example of a cellular phenotypic transformation during cardiac development.


Subject(s)
Heart Atria/embryology , Heart Septum/embryology , Myocardium/ultrastructure , Animals , Chick Embryo , Epithelium/ultrastructure , Extracellular Matrix/ultrastructure , Mesoderm/ultrastructure
17.
Microsc Res Tech ; 40(1): 22-36, 1998 Jan 01.
Article in English | MEDLINE | ID: mdl-9443154

ABSTRACT

Several microscopical techniques, such as high resolution light microscopy, Normaski microscopy, laser confocal and transmission electron microscopy, were used in a correlative morphological study of human osteoarthritic (OA) cartilage. Emphasis was made on the characterization of chondrocytes heterogeneity observed in this tissue. Novel findings were assessed in the morphological and immunocytological study of the chondrocytes organized in aggregates or "clones" typical of this degenerative disease, consisting of the modification of certain elements of the cytoskeleton that influence changes in the cell shape. Also, the presence of cilia and centrioles found in certain cell raised the question if chondrocytes are able to move and regroup as an alternative mechanism to mitosis in the formation of cell clusters or "clones." The presence of two types of secretory chondrocytes was observed and discussed. The use of a correlative approach of several microscopical techniques in a systematic morphological and immunocytological characterization of chondrocyte population within the fibrillated and nonfibrillated human osteoarthritic cartilage gave complementary information that could be important for a better understanding of the histopathogenesis of OA.


Subject(s)
Cartilage, Articular/ultrastructure , Microscopy/methods , Osteoarthritis/pathology , Clone Cells/ultrastructure , Humans , Microscopy, Confocal , Microscopy, Electron , Phenotype
18.
J Mol Cell Cardiol ; 29(9): 2503-11, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9299373

ABSTRACT

The effect of heparin (1-200 microg/ml) on several functional properties of 4-day-old embryonic hearts was studied. Intracellular recordings either from cells of the atrium, the atrio-ventricular canal or the ventricle were made on the isolated and perfused hearts. In all impaled myocardial cells, heparin produced an increment in the maximal rate of rise and amplitude of the action potentials and the duration was slightly diminished. In addition, heparin provoked a reduction in the spontaneous beating frequency, while the electrical excitability and the conduction velocity of the atrium and the ventricle were increased. The measurements of atrio-ventricular latency revealed that it was diminished, i.e. the propagation of impulses through the atrio-ventricular canal was improved. Simultaneously with these changes, heparin incremented the amplitude of contraction of either the atrium or the ventricle importantly.


Subject(s)
Heart/embryology , Heart/physiology , Heparin/pharmacology , Animals , Calcium/pharmacology , Chick Embryo , Electric Conductivity , Electrophysiology , Heart/drug effects , Heart Rate/drug effects , Membrane Potentials/drug effects , Myocardial Contraction/drug effects
19.
Exp Parasitol ; 85(2): 149-57, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9030665

ABSTRACT

During leishmania infection, parasites are inoculated to the human host through the bite of a sandfly vector into the dermis, where they first interact with tissue components, cells and extracellular matrix molecules. Since collagen is the most abundant component of the skin matrix, we investigated whether there is a specific interaction of Leishmania mexicana promastigotes with this host component. Promastigotes were able to attach to collagen fibrils and move through the matrix of mouse skin sections and to penetrate easily into a type I collagen gel. Denatured type I collagen coated beads (Cytodex 3) readily bound to the parasite surface. The interaction of promastigotes with type I collagen was dose dependent and saturable and was competitively and specifically inhibited with increasing concentrations of gelatin. Biotin-labeled parasite surface molecules were able to associate with both denatured collagen from microcarriers and native type I collagen from bovine kidney. It is suggested that the presence of parasite cell membrane receptors to collagen may confer a specific tropism for the skin, where collagen is the most abundant component of the matrix.


Subject(s)
Collagen/metabolism , Leishmania mexicana/metabolism , Leishmaniasis, Diffuse Cutaneous/parasitology , Skin/parasitology , Animals , Biotin , Frozen Sections , Humans , Leishmania mexicana/ultrastructure , Mice , Microscopy, Electron , Microscopy, Electron, Scanning , Microspheres , Skin/chemistry , Skin/metabolism , Skin/ultrastructure
20.
Biocell ; 20(3): 191-200, 1996 Dec.
Article in English | MEDLINE | ID: mdl-9031589

ABSTRACT

Human samples of articular cartilage from the knee of a clinically classified osteoarthritic patient, assessed by arthroscopy as part of the surgical treatment was studied by light and transmission electron microscopy. This particular case differed from others already reported in the variability of cell phenotype within the aggregates or "clones" frequently present in the osteoarthritic cartilage. The most common morphology of "clonal" cells forming the aggregates were large and rounded with an euchromatic nucleus. The cytoplasm was characterized by the presence of alternately clear and dense sites. At the ultrastructural level it was seen that the clear sites were formed by disrupted intermediates filaments and small particles, and that the dense sites were constituted by the segregation of different organelles of the chondrocytes. In addition, there were atypical aggregates composed only by secretory cells or by degenerating chondrocytes. Furthermore, a complex structure consisting of a very large cell inside a giant lacunae delimited by electron-dense material with small vesicles is described as a novel finding. The variability in the chondrocyte phenotype of the aggregates described here could be an indication of a better prognosis; nevertheless, the follow-up of the evolution of this patient is needed in order to know the final outcome.


Subject(s)
Cartilage, Articular/pathology , Osteoarthritis/pathology , Cell Aggregation , Cell Movement , Clone Cells/pathology , Humans , Phenotype
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