Immunohistochemical study on contents of beta-amyloid, alpha-actin and collagen IV in cerebral small vessels with unknown type of pathological lesion / 法医学杂志

OBJECTIVE@#To investigate the structural characteristics of the cerebral small vessels with an unknown type of pathological lesion (UTPL).@*METHODS@#Contents of beta-amyloid, alpha-actin and collagen IV in cerebral small vessels with UTPL were studied by Congo red staining, immunohistochemical staining and computer image analysis.@*RESULTS@#The low expression levels of alpha-actin and collagen IV (P<0.05) were observed in tunica media of the vessels with UTPL, and no positive expression of beta-amyloid (P>0.05) was observed in these vessel walls. The expressions of proteins mentioned above in UTPL were different from those of cerebral amyloid angiopathy(CAA) and hyaline arteriolosclerosis.@*CONCLUSION@#UTPL was different from CAA or hyaline arteriolosclerosis in pathologic feature.

Placenta humana chagásica: alteración estructural y citoquímica de vasos sanguíneos / Human chagasic placenta: structural and cytochemical changes of blood vessels

Diversos autores han demostrado que los vasos sanguíneos coronarios pueden tener alguna participación en la patogenia de las alteraciones cardíacas en la enfermedad de Chagas. El objetivo del presente trabajo fue detectar alteraciones estructurales y citoquímicas en vasos sanguíneos de placentas humanas a término mediante microscopía óptica y electrónica, considerando la posibilidad de su participación en la patogenia del pasaje transplacentario del agente causal del Chagas. En dos de seis placentas chagásicas provenientes de embarazadas a término con serologías positivas para enfermedad de Chagas, se halló estrechamiento u oclusión de vasos fetales de las vellosidades coriales con aspecto hialinizado de sus paredes mediante microscopía óptica y actividad de fosfatasa ácida aumentada en el endotelio vascular mediante ultracitoquímica. El estrechamiento de la luz vascular mediante ultracitoquímica. El estrechamiento de la luz vascular podría deberse a la participación del músculo liso y del endotelio.

Morphological evidence of pulmonary vascular leakage through gaps observed with casting methods and S.E.M

We have used selective casting methods to separate pulmonary elastin from vascular elastin in the lungs of rabbits, dogs and pigs. The lungs are digested with 0.1 N NaOH at 75 degrees C for 24 approximately 48 hours with frequent turning as the lungs are filled with air to about 80% of the vital capacity prior to the casting which is done at pressure of 20 approximately 50 mmHg. After vascular injections, we saw many small globular bits of casting material well separated from cast vessels and lying in the pulmonary elastin. Surface forces should make the casting material creep along the vessels even if they are not completely filled, so that the spherical shape is the one expected if the case is extruded into the parenchymal space and the air space. We conclude that this suggests that the pulmonary circulation is partially and temporarily 'open' as seen in the spleen and some other organs, rather than a completely 'closed' one as is generally accepted. At least some of these extravasations may be associated with lymphatics, although we have not proved this.

Ultrastructure of sciatic nerve of armadillo infected with Mycobacterium leprae.

Ultrastructural observation of sciatic nerves from eight Armadillos were made. Six animals had intravenous inoculation of M. leprae, one had of foot pad, while one had natural leprosy. The available nerves were biopsied at various time sequence ranging from five weeks to twenty four months. Semithin sections did not reveal any neuropathy. Ultrastructurally perineurium was thick and endoneurial collagen was increased. Initially demyelination of non-myelinated fibres was seen in all nerves irrespective of mode of infection. This was followed by demyelination of small myelinated fibres. Active remyelination was predominantly after 17 months. Schwann cell activity was increased and various stages of division were seen. Bacilli were extracellular, intraxonal, in endothelium and in perineurium. Significant observations were on blood vessels. These observations are discussed.

Electron microscopic study of the vascular endothelial cell in dengue hemorrhagic fever.

Electron microscopic studies were performed from skin biopsies taken from patients aged between 1-14 years suffering from dengue hemorrhagic fever. Several capillaries showed marked distortion, but severely damaged vessels were not observed in this study. In many cases, however, swelling of a single endothelial cell was noted. This was characterized by a rarefaction of the cytoplasm and formation of the plasma membrane which extruded into lumen and narrowed it. In many vessels examined, these blebs became detached from the endothelium and were found free within the capillary lumen. Myelin figures were often observed in such vessels. Mitochondria in the swollen endothelial cells often showed contraction of the inner compartments. Although, most of the endothelial junctional complexes were intact, several gap formations, in vascular wall were observed. Vacuolation of the cytoplasm and increase in the pinocytotic vesicles in endothelial cells which represented transport of plasma fluids from the capillary to the pericapillary space were quite evident. In no case did there seem to be marked alternation of the basement membrane of the capillary. The morphological alterations observed in this study only suggest the non-specific response of the dermal capillaries. These findings were similar to the findings observed in capillaries after being subjected to heat or ischemia.