Digitum Colección:http://hdl.handle.net/10201/177292024-03-28T20:18:53Z2024-03-28T20:18:53ZHistochemical and ultrastructural study of skeletal muscle in patients with sepsis and multiple organ failure syndrome (MOFS)Díaz, N. L.Finol, H. J.Torres, S. H.Zambrano, C. I.Adjounian, H.http://hdl.handle.net/10201/925512020-05-22T23:10:08Z1998-01-01T00:00:00ZTítulo: Histochemical and ultrastructural study of skeletal muscle in patients with sepsis and multiple organ failure syndrome (MOFS)
Autor/es principal/es: Díaz, N. L.; Finol, H. J.; Torres, S. H.; Zambrano, C. I.; Adjounian, H.
Resumen: Muscle biopsies for histochemical and
ultrastuctural analysis were obtained from seven
critically ill patients admitted to the Intensive Care Unit
of the "Domingo Luciani" Hospital, Caracas, Venezuela.
The sample included two patients with sepsis of
abdominal origin, and five that presented sepsis/MOFS,
with renal, hepatic, and respiratory disturbances and
muscular weakness. Sections were examined for myosin
adenosine triphosphatase (ATPase) after pre-incubation
with both acid buffer (pH 4.37 and 4.6) and alkaline
buffer (pH 10.3), for reduced nicotinamide dinucleotide
diaphorase (NADHd), and for a-glycerophosphate
dehydrogenase (a-GPDH). Sections were stained with
hematoxilin and eosin to look for pathological changes
and examined with a transmission electron microscope.
Skeletal muscle of patients in early stage of sepsis
showed a normal aspect with light microscopy, but at the
ultrastructural level some of the fibres showed atrophy
and some capillaries looked altered . Patients with
sepsis/MOFS exhibited an evident muscle disorder with
oedema. infiltrate, atrophy and segmental necrosis. All
fibre types showed decrease in diameter; specially fibre
types IIA and lIB . Intramuscular capillaries were
thickened and occluded , indexes of capillarity were
slightly reduced, and fibre oxidative activity was
decreased. At ultrastructural level fibres showed severe
atrophy, contractile system disorganization and
segmental necrosis. Capillaries were also altered and the
mononuclear cell infiltrate was abundant and represented
by macrophages. lymphocytes and mastocytes.1998-01-01T00:00:00Zβ-lapachone induced cell death in human hepatoma (HepA2) cellsLai, C.C.Liu, T. J.Ho, L. K.Don, M. J.Chau, Y. P.http://hdl.handle.net/10201/925482020-05-22T23:10:06Z1998-01-01T00:00:00ZTítulo: β-lapachone induced cell death in human hepatoma (HepA2) cells
Autor/es principal/es: Lai, C.C.; Liu, T. J.; Ho, L. K.; Don, M. J.; Chau, Y. P.
Resumen: In present study we studied the cytotoxic
effects of B-lapachone, a potent anticancer drug, on the
human hepatoma cell line (HepA2) under serum-free
condition. Most cells died after 2 ,uM B-Iapachone
addition at 48 hours. No apoptotic characteristics of
DNA ladder was documented by agarose DNA electrophoresis. The blockage of cell cycle at S phase and
unscheduled DNA synthesis were demonstrated by flow
cytometric analysis and anti-bromodeoxyuridine
immunocytochemistry. Ultrastructural observation
showed that the swollen mitochondria, dilatation and
vesiculation of rER and proliferation of peroxisome-like
granules appeared within the cytoplasm of HepA2 cells
following drug treatment. Using enzyme cytochemistry,
both peroxidase and acid phosphatase activities but not
catalase activity were localised in these peroxisome-like
granules. Therefore, these results suggested that (a) 13-
lapachone has a novel cytotoxic effect on human
hepatoma cell; (2) B-lapachone induces the interruption
of the cell cycle and unscheduled DNA synthesis in
HepA2 cells; and (3) B-lapachone promotes the
proliferation of peroxisome-like granules containing
peroxidase and acid phosphatase activities without
evidence of catalase activity in hepatoma cell line.1998-01-01T00:00:00ZThe cytoskeleton in skeletal, cardiac and smooth muscle cellsStromer, M. H.http://hdl.handle.net/10201/925472020-05-22T23:12:30Z1998-01-01T00:00:00ZTítulo: The cytoskeleton in skeletal, cardiac and smooth muscle cells
Autor/es principal/es: Stromer, M. H.
Resumen: The muscle cell cytoskeleton consists of
proteins or structures whose primary function is to link,
anchor or tether structural components inside the cell.
Two important attributes of the cytoskeleton are strength
of the various attachments and flexibility to accommodate the changes in cell geometry that occur during
contraction. In striated muscle cells, extramyofibrillar
and intramyofibrillar domains of the cytoskeleton have
been identifi ed , Evidence of the extramyofibrillar
cytoskeleton is seen at the cytoplasmic face of the
sa rcolemma in striated muscle where vinculin- and
dystrophin-rich costameres adjacent to sarcomeric Z
lines anchor intermedi a te filaments that span from
peripheral myofibrils to the sarcolemma. Intermediate
filaments also link Z lines of adjacent myofibrils and
may, in some muscles, link successive Z lines within a
myofibril at the surface of the myofibril. The intramyofibrillar cytoskeletal domain includes elastic titin
filaments from adjacent sarcomeres that are anchored in
the Z line and continue through the M line at the center
of the sa rcomere; inelastic nebulin filaments also
anchored in the Z line and co-extensible with thin
filaments; the Z line, which also anchors thin filaments
from adjacent sarcomeres; and the M line, which forms
bridges between the centers of adjacent thick filaments,
In smooth muscle, the cytoskeleton includes adherens
junctions at the cytoplasmic face of the sarcolemma,
which a nchor B-actin filaments and intermediate
filaments of the cytoskeleton, and dense bodies in the
cytoplasm, which also anchor actin filaments and
intermediate filaments and which may be the interface
between cytoskeletal and contractile elements.1998-01-01T00:00:00ZAntigen detection on resin sections and methods for improving the immunogold labeling by manipulating the resinBrorson, S. H.http://hdl.handle.net/10201/925462020-05-22T23:09:05Z1998-01-01T00:00:00ZTítulo: Antigen detection on resin sections and methods for improving the immunogold labeling by manipulating the resin
Autor/es principal/es: Brorson, S. H.
Resumen: Considering the importance of immunolocalization of cellular substances combined with good
ultrastructure and ease of use , this review is focused on
the use of resin and the possibilities of manipulating the
resin before and after embedding in order to improve the
immunolabeling of resin sections for electron
microscopy. The qualities of acrylic re sin s and
conventional epoxy resin for immunoelectron microscopy are discussed. Acrylic sections are usually more
suited for immunoelectron microscopy than conventional epoxy sections. Different etching procedures
(sodium ethoxide or sodium metaperiodate) may be
applied to conventional epoxy sections to enhance the
yield of immunolabeling. Lately, a method which does
not involve any kind of etching has been developed for
enhancing the immunogold labeling of epoxy sections
up to about 8 times. This method involves increased
concentration of accelerator in the epoxy resin mixture
when processing the tissue. The ultrastructural
preservation of the tissue is important in immunoelectron microscopical procedures. and not only the
intensity of the immunolabeling: in this respect no resin
may compete with the widely used epoxy resins.1998-01-01T00:00:00Z