RESUMO
Decreased levels of glycosaminoglycans (GAGs) have been observed in the kidney and other organs, in human and animal models of diabetes. Long-term administration of heparins and other glycosaminoglycans has demonstrated a beneficial effect on morphological and functional kidney abnormalities in diabetic rats. We assessed the effect of pentosan polysulfate sodium (PPS), a semi-synthetic glycosaminoglycan with low anticoagulant activity, on kidney involvement in streptozotocin diabetic rats. Diabetes was induced in male Sprague-Dawley rats by i.v. administration of streptozotocin (STZ). Animals were randomly allocated to three groups: C = control, STZ and STZ + PPS = pretreated with PPS (15 mg/kg, s.c.). After three months of follow-up, blood and 24 h-urine samples were obtained, the animals were sacrificed and the kidney microdissected for morphometric analysis. Urinary albumin excretion was markedly increased in untreated diabetic rats (C = 0.26 ± 0.03 vs STZ = 7.75 ± 1.8 mg/24 h) and PPS treatment partially prevented the albumin rise (3.7 ± 0.7 mg/24 h), without affecting the metabolic control HbA1c (C = 3.6 ± 1.7; STZ = 8.82 ± 0.47; STZ + PPS = 8.63 ± 0.54). Electron microscope observation revealed typical renal lesions described in experimental diabetes (STZ group). PPS administration prevents the tubular basement membrane thickening and the loss of cytoarchitecture induced by experimental diabetes. Our data demonstrate that long-term administration of PPS has a favourable effect on morphological and functional abnormalities in kidneys of diabetic rats and suggests a potential therapeutic use for this compound.
Assuntos
Albuminúria/prevenção & controle , Diabetes Mellitus Experimental/tratamento farmacológico , Nefropatias Diabéticas/prevenção & controle , Membrana Basal Glomerular/efeitos dos fármacos , Rim/efeitos dos fármacos , Poliéster Sulfúrico de Pentosana/uso terapêutico , Albuminúria/etiologia , Animais , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/urina , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 1/urina , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/urina , Avaliação Pré-Clínica de Medicamentos , Proteínas da Matriz Extracelular/metabolismo , Rim/patologia , Masculino , Poliéster Sulfúrico de Pentosana/farmacologia , Distribuição Aleatória , Ratos , Ratos Sprague-DawleyRESUMO
Malaria, a common health problem in certain parts of the world, has a considerable morbidity and mortality. This work reports under electron microscopy studies serious ultrastructural kidney damage such as extensive cytoplasmic vacuolation, vesiculation and autophagic vacuoles in proximal tubular cells. A thickened endothelial wall on peritubular capillary, interdigitation disorganization and significant decrease of their number in some areas were detected. Swollen rough endoplasmic reticulum, swollen mitochondria, and parasitized erythrocytes were observed. Many epithelial cells exhibited cytoplasmic areas of autophagia and a myelin-like form. A tubular cell presented severe cytoarchitecture alterations. Abundant lipid droplets were noticed. Almost total loss of interdigitations, rough endoplasmic reticulum vesiculation, peritubular capillaries with endothelial cells thickened cytoplasm, papillary processes projected to the lumen, and an inflammatory infiltrate of macrophages were also observed. These ultrastructural kidney changes could cause, on the basis of their clinical and pathologic expressions, a fat accumulation, an acute temporary reversible glomerulonephritis, a chronic progressive irreversible glomerulonephritis, and an acute renal failure (ARF).
Assuntos
Glomérulos Renais/ultraestrutura , Túbulos Renais Proximais/ultraestrutura , Rim/ultraestrutura , Malária/patologia , Microscopia Eletrônica de Transmissão/métodos , Plasmodium berghei/fisiologia , Animais , Citoplasma/química , Citoplasma/ultraestrutura , Modelos Animais de Doenças , Rim/parasitologia , Glomérulos Renais/parasitologia , Túbulos Renais Proximais/parasitologia , Lipídeos/análise , Malária/transmissão , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
The use of chemical pesticides and herbicides has increased environmental pollution and affected ichthyofauna in the watersheds where they are used.We studied the effect of an herbicide, triazine, on the kidneys of two species (Caquetaia kraussii and Colossoma macropomum )widely found in Caribbean and South American rivers.In Venezuela,these species are abundant and have a high aquaculture potential because they may be cultured and reproduced in captivity.Four kidney samples from juveniles of each species exposed to the herbicide were examined by Transmission Electron Microscopy.Kidney tubule alterations included loss of plasmalemma and cell interdigitations, misshaped mitochondria,decrease in rough endoplasmic reticulum and free polysomes,and the presence of autophagic vacuoles and primary lysosomes.These alterations at the cellular level may explain fish behaviour in terms of kidney tubule pathology,and relative amounts and conditions of organelles within affected cells
Assuntos
Animais , Atrazina/toxicidade , Pesqueiros , Peixes , Herbicidas/toxicidade , Rim/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Atrazina/análise , Biomarcadores/análise , Ciclídeos , Herbicidas/análise , Túbulos Renais/química , Túbulos Renais/efeitos dos fármacos , Rim/química , Rim/ultraestrutura , Mitocôndrias/química , Mitocôndrias/efeitos dos fármacos , VenezuelaRESUMO
The use of chemical pesticides and herbicides has increased environmental pollution and affected ichthyofauna in the watersheds where they are used. We studied the effect of an herbicide, triazine, on the kidneys of two species (Caquetaia kraussii and Colossomna macropomum) widely found in Caribbean and South American rivers. In Venezuela, these species are abundant and have a high aquaculture potential because they may be cultured and reproduced in captivity. Four kidney samples from juveniles of each species exposed to the herbicide were examined by Transmission Electron Microscopy. Kidney tubule alterations included loss of plasmalemma and cell interdigitations, misshaped mitochondria, decrease in rough endoplasmic reticulum and free polysomes, and the presence of autophagic vacuoles and primary lysosomes. These alterations at the cellular level may explain fish behaviour in terms of kidney tubule pathology, and relative amounts and conditions of organelles within affected cells.
Assuntos
Atrazina/toxicidade , Pesqueiros , Peixes , Herbicidas/toxicidade , Rim/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Atrazina/análise , Biomarcadores/análise , Ciclídeos , Herbicidas/análise , Rim/química , Rim/ultraestrutura , Túbulos Renais/química , Túbulos Renais/efeitos dos fármacos , Mitocôndrias/química , Mitocôndrias/efeitos dos fármacos , VenezuelaRESUMO
Biopsy specimens of cervico-scutular muscles obtained from animals injected with bee crude venom were prepared for electron microscopy studies. At 6 h from Apis mellifera venom injection, in mice under transmission electron microscopy, the muscular fibres presented different atrophy levels with increment of the intermyofibrillar spaces. Tubules and sarcoplasmic reticulum elements were altered, in some places only tubular fragments and an increment of the intermyofibrillar spaces were noticed as well as loss of fibre regularity and prominent triads. In subsarcolemma region, areas lacking myofibrils and mitochondria damages were observed. Muscular segmental necrosis and atrophy areas were observed. Neuromuscular junctions were altered. The number of synaptic vesicles was very variable and synaptic clefts showed irregularities. A decrease in the number and arrangement of the synaptic clefts, as well as free polysomes, suggesting regeneration processes, were also observed. The myelinic nerves exhibited in the axon or in the wall vacuolisation areas. The presence of severe muscular lesions, the finding of venom activities in the presynaptic region and the detection of damages in the neuromuscular junctions at different chronological stages of our experiments indicate that the bee venom is highly toxic for neuromuscular structures.
Assuntos
Venenos de Abelha/toxicidade , Abelhas , Músculo Esquelético/efeitos dos fármacos , Junção Neuromuscular/efeitos dos fármacos , Nervos Periféricos/efeitos dos fármacos , Animais , Venenos de Abelha/administração & dosagem , Injeções Intraperitoneais , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/ultraestrutura , Músculo Esquelético/ultraestrutura , Junção Neuromuscular/ultraestrutura , Nervos Periféricos/ultraestruturaRESUMO
An inflammatory process may be involved in nitric oxide production in skeletal muscle of type 2 diabetic patients. Nitric oxide generation in skeletal muscle was assessed in 14 non-complicated type 2 diabetic patients and in 12 healthy subjects. In samples of quadriceps femoris muscle, endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), nitrite, nitrate and nitrotyrosine were determined. The macrophage-specific antigen CD163, the T-cell membrane factor CD154 and tumour necrosis factor-alpha (TNF-alpha) were also assayed. In six patients, ultrastructural analysis of muscle was performed. Nitrites and nitrates were increased in patients as compared to controls (22.7+/-4.5 and 32.7+/-7.0 vs 16.0+/-2.9 and 22.8+/-4.0 micromol/mg protein; P<0.001, Mann-Whitney U test). Endothelial NOS was similar in diabetic and control subjects (36.4+/-13.8 vs 36.3+/-6.8 ng/mg protein), contrasting with the significant increase of iNOS recorded in patients (34.3+/-13.0 vs 8.5+/-2.8 ng/mg protein, P<0.00002). Nitrotyrosine levels were higher in the patient than in the control group (42.1+/-24.4 vs 10.3+/-2.5 ng/mg protein, P<0.00002), as were CD163 (10-fold) and TNF-alpha (fourfold) levels. Furthermore, CD154 levels were detectable only in the patient samples (10.2+/-5.3 ng/mg protein). By multiple-regression analysis, changes in glycated haemoglobin values could predict 96% variation in nitrotyrosine. Macrophages were present in all muscle samples analysed by electromicroscopy. The increased levels of CD163, CD154 and TNF-alpha indicate that an inflammatory process occurs in skeletal muscle of type 2 diabetic patients. This may contribute to iNOS induction, muscle damage and insulin resistance.
Assuntos
Diabetes Mellitus Tipo 2/imunologia , Diabetes Mellitus Tipo 2/metabolismo , Músculo Esquelético/imunologia , Músculo Esquelético/metabolismo , Óxido Nítrico/metabolismo , Adulto , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/tratamento farmacológico , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Hipoglicemiantes/uso terapêutico , Inflamação , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Músculo Esquelético/ultraestrutura , Óxido Nítrico Sintase/análise , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Receptores de Superfície Celular/análise , Receptores OX40 , Receptores do Fator de Necrose Tumoral/análise , Análise de Regressão , Fator de Necrose Tumoral alfa/análiseRESUMO
Axenic cultures of pure Trypanosoma rangeli were used to investigate the relation between ultrastructure and activity in the mitochondrion. Every other day, ultrathin sections were obtained from cultivated flagellates and, subsequently, observed in order to register changes in the cytoarchitecture of the organelle. Culture samples were incubated in tetrazolium salts to determine the mitochondrion's metabolic state. The results show a high correspondence between mitochondrion ultrastructural shape and function of the same organelle in populations of T. rangeli maintained under in vitro conditions.
Assuntos
Mitocôndrias/ultraestrutura , Trypanosoma/ultraestrutura , Animais , Microscopia Eletrônica de Transmissão , Mitocôndrias/metabolismo , Trypanosoma/metabolismoRESUMO
Bee accidents incidence is underestimated because many people do not consult to the physicians. Here it is described for the first time the severe mice adrenal gland damage induced by Apis mellifera venom. Biopsy specimens were obtained from mice adrenal gland and after sample preparation observed in Hitachi H-7100 electron microscope. In this work the ultrastructural analysis showed, 6 h after injection, a non homogeneous smooth endothelial reticulum, and in some places loss of plasma membrane. The fenestrae spaces were bigger and detritus in the capillary lumen were observed. Erythrocytes were seen in a cortical cell. After 48 h of venom injection, expanded fenestrae were observed. Capillary basal membrane was interrupted. Myelin-like figures and autophagic vacuoles were noticed. Swollen smooth endoplasmic reticulum elements and endothelial unfolding to the light were seen. Moreover, swollen Golgi and mitochondria were observed, in some places forming myelinic-like figures. At 144 h after venom injection, widened spaces were noticed in capillary fenestrae. Cellular section showed swollen and lost smooth endoplasmic reticulum elements. Smooth endoplasmic reticulum tubules disappearance suggested non steroidogenesis. In conclusion, we suggest that some of the bee envenoming human clinical manifestations, as is observed in mice, are determined by suprarenal gland damage produced by toxins present in this venom.
Assuntos
Córtex Suprarrenal/efeitos dos fármacos , Venenos de Abelha/toxicidade , Abelhas , Córtex Suprarrenal/ultraestrutura , Animais , Abelhas/fisiologia , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Organelas/efeitos dos fármacos , Organelas/ultraestruturaRESUMO
En el presente trabajo se realizó un estudio mediante microscopÝa de luz y electrónica de transmisión con el fin de estudiar las alteraciones musculares producidas en el músculo de la lengua en pacientes con carcinoma epidermoide. Las anomalÝas estructuras observadas incluyeron, alteraciones tanto en el sistema contrßctil como sarcotubular, por otro lado se observó atrofia y necrosis segmentaria, alteración de mitocondrias y proliferación de organelos, asÝ como vaculolas, lisosomas y grßnulos de lipofucsina. El infiltrado mononuclear estuvo representado principalmente por neutrófilos, macrófagos y mastocitos. Este estudio representa el primer reporte sobre las alteraciones ultraestructurales a nivel del músculo de la lengua producida por esta patologÝa maligna
Assuntos
Humanos , Masculino , Adulto , Feminino , Pessoa de Meia-Idade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/ultraestrutura , Neoplasias da Língua , Distribuição por Idade , Biópsia , Diagnóstico Clínico , Lisossomos , Microscopia , Microscopia Eletrônica de Varredura , Mitocôndrias Musculares , Serviço Hospitalar de Oncologia/estatística & dados numéricos , Distribuição por Sexo , Língua , Vacúolos , VenezuelaRESUMO
Acute renal insufficiency related to acute tubular necrosis is the most important complication caused by crotalid bite. For structural and ultrastructural studies of renal tissue, mice injected with crude venom or C. vegrandis haemorrhagic fraction, and controls were tested. Light microscopy analysis of kidneys at 24 h after injection of crude venom showed only moderate alterations such as tubular epithelia microvacuolisation. After 120 h marked glomerular and tubular capillaries congestion and interstitial oedema were observed. At 24 h after Uracoina-1 i.p. injection, intense glomerular and peritubular capillaries congestion was observed. Electron microscopic analysis of kidneys 24 h after i.p. injection of crude venom showed, capillary endothelial cell debris and pleomorphic mitochondria. Loss of interdigitations regularity, abundant dense bodies and light widening of the basal membrane were observed. Autophagic vacuoles were present as well as endothelia unfolding to the lumen and altered forms of podocytes. At 48 h, augmented endothelia without fenestrae formation with sequestration of low optical density debris inside the protrusions were noticed. At 120 h, capillary residues with loss of the endothelium were present and the basal membrane was widened. At 15 days, the number of vesicles and vacuoles in the tubules was increased and only few interdigitations were noticed. Autophagic vacuoles and mitochondrial matrix low electron density were observed. At 120 h after injection of crude venom, vascular damage with loss of capillary cell structures and collagen fibres were observed. At 24 h of haemorrhagic fraction injection, presence of autophagic vacuoles and myelinic figures were noticed.
Assuntos
Venenos de Crotalídeos/toxicidade , Crotalus , Rim/efeitos dos fármacos , Animais , Capilares/efeitos dos fármacos , Capilares/ultraestrutura , Venenos de Crotalídeos/administração & dosagem , Venenos de Crotalídeos/isolamento & purificação , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Edema/patologia , Injeções Intraperitoneais , Rim/patologia , Glomérulos Renais/irrigação sanguínea , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/ultraestrutura , Túbulos Renais/irrigação sanguínea , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/ultraestrutura , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos , Ratos , Ratos Sprague-DawleyRESUMO
Arterial hypertension produces changes along the vascular tree. However, there are few reports on its effect on human muscle capillaries. This study demonstrates the effects of essential hypertension on the capillaries of human quadriceps muscle. Muscle biopsy was taken from quadriceps femoris in eight men with recent diagnosis of essential hypertension, without treatment. Biopsies were also taken from eight normotensive men and were used as controls. Fiber types were classified by ATPase reaction, capillaries counted in alpha-amylase-PAS stained sections and ultrastructure studied by conventional methods of transmission electron microscopy. No changes were found in capillaries or muscle fiber types by histochemical methods. However, electron microscopy revealed abnormal capillaries with endothelial cells infoldings into the lumen, as well as occluded or degenerated capillaries. In some cases the endothelial cell area covered by pericytes was increased. Basement membrane of capillaries was frequently increased in width, sometimes irregularly, and in other instances it was reduplicated. In transversely sectioned capillaries lumen diameter was reduced and wall thickness was increased, although total diameter was unchanged. In hypertensive patients the finding of some degenerated capillaries adjacent to muscle fibers could be interpreted as the beginning of a process of rarefaction. Some capillaries showed morphological changes, and the ratio wall thickness/lumen was increased.
Assuntos
Capilares/patologia , Hipertensão/patologia , Músculo Esquelético/irrigação sanguínea , Adenosina Trifosfatases/metabolismo , Adulto , Pressão Sanguínea/fisiologia , Capilares/ultraestrutura , Humanos , Hipertensão/fisiopatologia , Masculino , Fibras Musculares de Contração Rápida/classificação , Fibras Musculares de Contração Rápida/enzimologia , Fibras Musculares de Contração Lenta/classificação , Fibras Musculares de Contração Lenta/enzimologia , Músculo Esquelético/enzimologia , Músculo Esquelético/ultraestrutura , Pericitos/ultraestrutura , Coxa da PernaRESUMO
In South America rattlesnake venom activities have not been entirely characterised. Some studies have shown haemorrhagic, myotoxic, and neurotoxic effects as manifestations of envenoming in experimental animals and humans. Biopsy specimens were obtained from liver and immediately fixed in situ and observed in Hitachi H-500 and H-7100 electron microscopes. In this work the ultrastructural analysis of experimental mice liver showed hepatocytes with increased lipid droplets content and significant vacuolation in areas of their cytoplasm limiting with the Disse space. Lysosomes and altered peroxisomes exhibiting a very dense electron content were also evident. Mitochondrial pleomorphism including cup-shaped and ring-shaped mitochondria were frequently found. The cristae were scarce or absent in the majority of mitochondria observed. The rough endoplasmic reticulum showed a preferentially disposition lining the outer mitochondrial membranes. In some section glycogen particles were scarce and lipofuchsin granules could be observed. Red blood cells showed endothelial cell adherence and, in many instances, the liver sinusoids were observed plugged with aggregated red blood cells. In conclusion, using an animal model that probably correlates well with the pathological effects found in envenomed humans, we have shown the severe hepatocellular alterations caused by this venom.
Assuntos
Venenos de Crotalídeos/toxicidade , Crotalus , Fígado/patologia , Animais , Fígado/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia EletrônicaRESUMO
The ultrastructural study of adrenal gland from mice experimentally infected with Trypanosoma evansi, in addition to intravascular and intracellular trypanosomes, showed different degrees of cortical cell alterations and capillary wall modifications. Beside its biological scope, these results suggest a role for the adrenal cortex to partake in Surra's etiopathogenesis and describe for the very first time a T. evansi intracellular stage.
Assuntos
Córtex Suprarrenal/ultraestrutura , Tripanossomíase/patologia , Córtex Suprarrenal/parasitologia , Animais , Feminino , Cavalos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica , Trypanosoma/isolamento & purificação , Trypanosoma/ultraestrutura , Tripanossomíase/etiologia , Tripanossomíase/parasitologia , VenezuelaRESUMO
In this ultrastructural study we examined skeletal muscle fibres from mice intraperitoneally inoculated with a sublethal dose of Crotalus vegrandis (rattlesnake) venom. The group of mice inoculated presented neurological symptoms characterised by respiratory failure and hind limbs paralysis. Skeletal muscle fibres showed different degrees of alterations. Most of them presented the characteristic pattern of necrosis in progress. Atrophied and hypercontracted fibres were frequently seen. Some atrophied and necrotic fibres showed several nucleoli-like bodies in the nucleus. In the atrophic and hypercontracted fibres, sarcoplasmic vacuolation and abnormal mitochondria with stacked cristae were observed. Areas of segmental necrosis were also frequently found. In connection with these altered muscle fibres, capillary abnormalities were detected. This study suggests that in envenomed mice respiratory failure symptoms may be related with muscle damage caused by Crotalus vegrandis venom components.
Assuntos
Venenos de Crotalídeos/toxicidade , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/ultraestrutura , Animais , Venenos de Crotalídeos/administração & dosagem , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/ultraestrutura , Músculo Esquelético/irrigação sanguínea , Atrofia Muscular/induzido quimicamente , Atrofia Muscular/patologia , NecroseRESUMO
The ultrastructural pathology of non-invaded hepatocytes located in close proximity to metastases from diverse gastrointestinal carcinomas was studied. Observed abnormalities included swelling of rough and smooth endoplasmic reticulum, proliferation of lysosomes, and mitochondrial alterations as presence of granules and paracrystalline inclusions, marked pleomorphism, and lack of cristae. These results show that, contrary to the classical conception, the non-invaded cells surrounding primary tumours or their metastases could be abnormal.
Assuntos
Neoplasias Gastrointestinais/patologia , Neoplasias Hepáticas/secundário , Fígado/ultraestrutura , Organelas/patologia , Retículo Endoplasmático Rugoso/patologia , Retículo Endoplasmático Rugoso/ultraestrutura , Retículo Endoplasmático Liso/patologia , Retículo Endoplasmático Liso/ultraestrutura , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/ultraestrutura , Lisossomos/patologia , Lisossomos/ultraestrutura , Mitocôndrias Hepáticas/patologia , Mitocôndrias Hepáticas/ultraestrutura , Organelas/ultraestrutura , Neoplasias Pancreáticas/patologiaRESUMO
As liver can be an important target organ in malaria, we performed an ultrastructural study of hepatic alterations in the final stage of Plasmodium berghei infection in mice. Significant hepatocyte abnormalities were found. An elevated number of cells showed mitochondria with a high electron-dense matrix and multiple changes in shape and size, alterations in the structure of Golgi complex, swelling and disorganisation of both rough and smooth-surfaced endoplasmic reticulum, differently shaped peroxisome nucleoids, and disappearance of glycogen granules. In other areas the hepatocytes were significantly altered with diminished microvilli and exhibited myelin-like figures, autophagic vacuoles, abundant lipid droplets, and swollen mitochondria in their cytoplasm. Necrotic and atrophied hepatocytes with scarce microvilli in the Disse space and biliary canaliculi could be seen. Parasitised red blood cells and parasite debris were found inside degenerated hepatocytes. Alterations were also noticed in microvasculature, including thickened endothelial cells with swollen mitochondria, lysosomes and autophagic vacuoles in their cytoplasm. Our results demonstrate that hepatocyte damage is an important finding associated with the advanced stages of P. berghei malarial infection, which may lead to liver dysfunction in this disease.
Assuntos
Fígado/ultraestrutura , Malária/patologia , Plasmodium berghei , Animais , Modelos Animais de Doenças , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BLRESUMO
Muscle biopsies for histochemical and ultrastructural 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 alpha-glycerophosphate dehydrogenase (alpha-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 IIB. 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.
Assuntos
Insuficiência de Múltiplos Órgãos/patologia , Músculo Esquelético/ultraestrutura , Sepse/patologia , Adolescente , Adulto , Capilares/ultraestrutura , Feminino , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/complicações , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/patologia , Sepse/complicaçõesRESUMO
Anopheles (Nyssorhynchus) aquasalis, is the main coastal vector of malaria from northeastern Venezuela to southeastern Brazil. Several authors have argued that An. aquasalis is a high polymorphic species while others indicated that it is a complex of closely related species. This investigation compared the morphology of An. aquasalis eggs from Sinamaica (Zulia State) and Yaguaraparo (Sucre State), the west and east of Venezuela, respectively. We were able to separate eggs from the two localities using discriminant analyses based on ratios and percentages of anterior and posterior tubercles measured by scanning electron microscopy. The results of this work suggest that An. aquasalis has high intraspecific variation.
Assuntos
Animais , Anopheles/embriologia , Óvulo , Microscopia Eletrônica de Varredura/instrumentaçãoRESUMO
An electron microscopic investigation was made in order to study capillary alterations in the muscle paraneoplastic phenomenon associated with different malignant tumours. Several abnormalities were found including basement membrane widening and lamination, endothelial hypertrophy, a varied degree of lumen occlusion, and proliferative changes in pericytes. A degenerative process leading to capillary necrosis was also observed. A mononuclear cell infiltrate formed by macrophages, lymphocytes and mast cells was seen. The capillary changes observed suggest the existence of an autoimmune vascular factor in the etiopathogenesis of muscle damage in this phenomenon.
Assuntos
Capilares/patologia , Músculo Esquelético/irrigação sanguínea , Neoplasias/fisiopatologia , Capilares/ultraestrutura , Feminino , Humanos , Masculino , Microscopia Eletrônica , Neovascularização PatológicaRESUMO
Anopheles (Nyssorhynchus) aquasalis, is the main coastal vector of malaria from northeastern Venezuela to southeastern Brazil. Several authors have argued that An. aquasalis is a highly polymorphic species while others indicated that it is a complex of closely related species. This investigation compared the morphology of An. aquasalis eggs from Sinamaica (Zulia State) and Yaguaraparo (Sucre State), the west and east of Venezuela, respectively. We were able to separate eggs from the two localities using discriminant analyses based on ratios and percentages of anterior and posterior tubercles measured by scanning electron microscopy. The results of this work suggest that An. aquasalis has high intraspecific variation.