RESUMEN
Valproic acid (VPA) is an antiepileptic drug used clinically. Because of its known teratogenic properties VPA is not recommended for women of child bearing age. The present study was designed to assess the effects of VPA on both fetal and maternal organs. Randomized groups of pregnant mice were treated as follows: Group 1 (n = 10) 500 mg/kg VPA/day on gestation days 8-11; Group 2 (n = 10) 600 mg/kg VPA/day on gestation days 8-11; and Group 3 (n = 4) saline-injected controls. On gestation day 18, the pregnant mice were euthanized, fetuses collected and prepared for scanning electron microscopy. In addition, fetal and maternal organs were processed for routine histology, immunohistochemistry for growth factors (TGF alpha, beta-1, beta-2 and EGF) and transmission electron microscopy. Scanning microscopy revealed specific lesions induced by VPA in the fetus, namely spina bifida occulta, exencephaly, and exophthalmia. On the other hand, there were no detectable morphological changes in fetal or maternal organs by routine histology, immunohistochemistry or electron microscopy. The data suggest that the lesions present in the fetus are due to a direct effect by VPA on retinoic acid, a ubiquitous compound that has a role in normal development, rather than the lack of transport of sufficient nutrients to the fetus as a result of placental insufficiency due to VPA-induced toxicity.
Asunto(s)
Anomalías Inducidas por Medicamentos/etiología , Anomalías Múltiples/inducido químicamente , Feto/efectos de los fármacos , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Pulmón/efectos de los fármacos , Placenta/efectos de los fármacos , Teratógenos/toxicidad , Ácido Valproico/toxicidad , Anomalías Inducidas por Medicamentos/embriología , Anomalías Inducidas por Medicamentos/patología , Anomalías Múltiples/embriología , Anomalías Múltiples/patología , Animales , Femenino , Feto/anomalías , Feto/ultraestructura , Edad Gestacional , Sustancias de Crecimiento/análisis , Riñón/ultraestructura , Hígado/embriología , Hígado/ultraestructura , Pulmón/embriología , Pulmón/ultraestructura , Ratones , Ratones Endogámicos BALB C , Microscopía Electrónica de Rastreo , Defectos del Tubo Neural/inducido químicamente , Defectos del Tubo Neural/embriología , Defectos del Tubo Neural/patología , Especificidad de Órganos , Placenta/ultraestructura , Embarazo , Disrafia Espinal/inducido químicamente , Disrafia Espinal/embriología , Disrafia Espinal/patología , Vitamina A/sangreRESUMEN
UNLABELLED: BACKGROUND/STUDY OBJECTIVES: We studied patients undergoing coronary artery bypass grafting. Risk factors for coronary disease were studied in conjunction with the histopathologic findings of the grafts prior to implantation. Our aim was to correlate the histologic condition of the grafts and evaluate the morphological changes in conjunction with existing risk factors. DESIGN/PATIENTS: In 10 candidates for surgical revascularization (nine males, mean age 60.8 years), the risk factor profile was studied (smoking, dyslipidaemia, hypertension, diabetes, family history) and the Body Mass Index was calculated. Of a total of 14 grafts, 10 were saphenous vein grafts and four left internal thoracic artery grafts. Histologic samples were studied under optical and electron microscopy. We studied the intima morphology and thickness, the width of the intercellular spaces, the texture of the subendothelial layer, the endothelial status, and the condition of the basal lamina. Histopathological changes were correlated with risk factors. RESULTS: Histopathological changes were observed in the wall structure of all grafts. The most important changes were found in the venous grafts, notably: intima thickening, existence of foam cells in the intima, widening of the intercellular spaces, subendothelial oedema, degeneration and detachment of endothelial cells, and wide multilayered basal lamina. The co-existence of two or more risk factors seems to exarcerbate morphological changes. CONCLUSION: Morphological changes are present principally in the walls of venous but also arterial conduits, even prior to implantation. These changes may be attributable to preparation techniques and preservation conditions of the grafts, but they could additionally be induced by coexisting risk factors. It is conceivable that these alterations could perhaps precipitate and accelerate atherosclerotic changes, inducing lumen narrowing or even occlusion of the graft postoperatively.
Asunto(s)
Puente de Arteria Coronaria/métodos , Enfermedad de la Arteria Coronaria/cirugía , Oclusión de Injerto Vascular/prevención & control , Arterias Mamarias/patología , Vena Safena/patología , Adulto , Anciano , Enfermedad de la Arteria Coronaria/patología , Humanos , Masculino , Arterias Mamarias/trasplante , Microscopía , Microscopía Electrónica de Transmisión de Rastreo , Persona de Mediana Edad , Selección de Paciente , Factores de Riesgo , Vena Safena/trasplante , Túnica Íntima/patologíaRESUMEN
Malformations of the palate were induced in white rat embryos following maternal exposure to retinoic acid (tretinoin). Five experimental groups and the controls were treated by the following protocol: Group 1: pregnant rats received 100 mg retinoic acid (RA)/kg b.w. suspended in corn oil on gestational day (GD) 11.5; Group 2: 20 mg RA/kg b.w. from GD 8-12; Group 3: 20 mg RA/kg b.w. from GD 7.5-11.5; Group 4: 100 mg RA/kg b.w. on GD 10-11; Group 5: 100 mg RA/kg b.w. on GD 10 and 12; Group 6 received corn oil vehicle from GD 7-14.5; and Group 6: served as non-injected controls. In all retinoic acid treated groups, varying degrees of clefts with occasional attempts of fusion were noted. The severity and frequency of the malformations were dependent on dosage or gestational day of drug treatment. Our results indicate that RA, even at the lowest dose tested (20 mg/kg b.w.) severely affects the various tissues constituting the embryonic palatal shelves by altering cell interaction and possibly programmed cell death. These events would then result in lack of or inadequate differentiation with subsequent formation of aberrant craniofacial architecture.
Asunto(s)
Anomalías Inducidas por Medicamentos/patología , Hueso Paladar/anomalías , Tretinoina/toxicidad , Animales , Fisura del Paladar/inducido químicamente , Fisura del Paladar/patología , Femenino , Hueso Paladar/embriología , Embarazo , Ratas , Ratas WistarRESUMEN
Exogenous retinoic acid has been found to be teratogenic in animals and man. Craniofacial defects induced by retinoic acid have stimulated considerable research interest. The present report deals with scanning electron microscopical observations of the craniofacial region concurrent with histological examination of craniofacial dysmorphism induced in rat embryos following maternal treatment treated with varying dosages of all-trans-retinoic acid (tretinoin). Two groups of pregnant rats were treated with rat embryos exposed to retinoic acid suspended in corn oil (100 mg/kg b.w. on gestational day 11.5 and 50 mg/kg b.w. on gestational day 10, 11 and 12 respectively). A third group was treated with corn oil (vehicle) while a fourth group remained untreated. A wide spectrum of congenital abnormalities, including exophthalmos, microphthalmia and anophthalmia, maxillo-mandibular dysostosis, micrognathia of both maxilla and mandible, cleft palate, subdevelopment of ear lobe, preauricular tags and macroglossia, were observed in the offspring of retinoic acid treated animals. The abnormalities were both time and dosage dependent, and characteristic of Treacher Collins syndrome when retinoic-acid was administered on gestational day 11.5. In contrast, when retinoic acid was administered were on gestational days 10-12, the defects were similar to those seen in the first and second pharyngeal arch syndrome, as well as in the oculo-auriculo-vertebral spectrum. Whereas our data support the hypothesis that all-trans retinoic-acid disturbs growth and differentiation of several embryonic cell types essential for normal craniofacial development, its mechanism of action remains unclear.
Asunto(s)
Anomalías Inducidas por Medicamentos/patología , Huesos Faciales/anomalías , Cráneo/anomalías , Tretinoina/toxicidad , Animales , Femenino , Masculino , Microscopía Electrónica de Rastreo , Embarazo , Ratas , Ratas WistarRESUMEN
For this study all-trans-retinoic acid was administered in pregnant white rats in their "prima gravida" pregnancy. Rats were divided in five groups. The first three groups were treated with 20 mg R.A./kg b.w. at several gestational days. The fourth group was treated with corn oil, while the fifth group remained untreated. All the animals were sacrificed during the first hours of the 21st gestational day. In the first group, three embryos, five absorptions and six compact embryonic masses were counted in litters. All the embryos presented exencephaly, combined with external anopthalmia. They also presented severe craniofacial malformations. In the second group, nine embryos and five compact embryonic masses were counted in litters. Three of the embryos presented exencephaly combined with external anopthalmia, while the six remaining presented complex craniofacial anomalies. In the third group, exencephaly was present in two embryos combined with anopthalmia, seven embryos had complex anomalies and four compact embryonic masses were counted in litters. Our results indicate the teratogenic involvement of all-trans-retinoic acid in anterior neural tube differentiation.
Asunto(s)
Anomalías Inducidas por Medicamentos/patología , Defectos del Tubo Neural/inducido químicamente , Defectos del Tubo Neural/patología , Tretinoina/toxicidad , Animales , Femenino , Embarazo , Ratas , Ratas WistarRESUMEN
Diverse studies on retinoic acid teratogenesis, during the recent years, indicate that the drug's analogues target on diverse cell population during differentiation in mammals. During an extended teratological protocol concerning retinoic acid influence in diverse embryonic tissue differentiation in experimental animals we studied all-trans-retinoic acid's influence on palatal development in the white rat embryo. For this purpose, six groups of white rat embryos were studied: Group 1 was treated with 100 mg/kilogram of body weight (k.b.w.) on gestational days (g.d.) 10th and 11th, Group 2 was treated with 100 mg all-trans-retinoic acid/k.b.w. on g.d. 11.5, Group 3 was treated with 50 mg all-trans retinoic acid/k.b.w. on g.d. 10th, 11th and 12th, Group 4 was treated with 50 mg all-trans-retinoic acid/k.b.w. on g.d. 11th and 12th, Group 5 was treated with 20 mg all-trans-retinoic acid/k.b.w. on g.d. 7.5, 8.5, 9.5, 10.5 and 11.5, Group 6 remained untreated. Embryonic heads aged 20 days were observed by light microscopy and scanning electron microscopy. In all treated groups clefts and malformations concerning the differentiation of palatal cell populations were observed. All our findings were compared with normal palatal morphology of untreated "control" embryos. Among the malformations, median clefts were observed, extended along only a part of the primary and all the secondary palate for group 2, the primary and secondary palate for groups 1, 3 and 5 while on group 4, an irregularity of the median palatal raphe and rugae were combined with a median incomplete cleft extended between the primary and secondary palate. Our results are discussed in relation with the international literature results.
Asunto(s)
Anomalías Inducidas por Medicamentos/patología , Hueso Paladar/anomalías , Hueso Paladar/patología , Tretinoina/toxicidad , Animales , Femenino , Microscopía Electrónica de Rastreo , Hueso Paladar/embriología , Ratas , Ratas WistarRESUMEN
Five healthy premolars were used for transmission electron microscopy examination and three-dimensional (3D) reconstruction of pulpal blood vessels and their surrounding nerves. Serial Epon thin sections were taken from specimens. After a series of preprocessing steps that included digitization, contrast enhancement, slice alignment, segmentation and interpolation, three dimensional surface representation was performed using the triangulation method. The findings showed that vessels were usually accompanied by a number of myelinated and unmyelinated nerves. The nerves shared a more or less common course with the vessels. Small arteries presented greater number of nerves in their vicinity, compared to small veins. In the sections examined, no direct contact between the nerve trunks and the wall of the vessels was found; the closest distance measured was approximately 67 microns. The common course of vessels and nerves suggested autonomic innervation on part of the myelinated axons.
Asunto(s)
Pulpa Dental/irrigación sanguínea , Pulpa Dental/inervación , Procesamiento de Imagen Asistido por Computador , Adulto , Gráficos por Computador , Pulpa Dental/diagnóstico por imagen , Humanos , Microscopía Electrónica , UltrasonografíaRESUMEN
Superficial fungal infections, including oral thrush, often affect aged full denture wearers and many individuals over 65 years old. The aim of this study was to examine the ultrastructural morphology of a very rare yeast, named Hanseniaspora uvarum/guillermondi, member of the Ascomycetes family, whose pathogenesis and behaviour is not widely known. The yeast was isolated from whitish lesions of the buccal mucosa of an 70 years old woman. The specimen was collected with a mouth swab and cultured in Sabourauds-Dextrose agar. The identification of the organism was performed on the Api 20C Aux system. The yeast colonies, after fixation in glutaraldehyde 3% for 1 hour were immersed in OsO4 1% solution for 1 hour and were "in tissue" stained with uranyl acetate. Ultrathin sections, were observed with TEM Jeol C x 100. Our ultrastructural observations showed that this yeast had a thick cell wall in which the outer surface appeared fuzzy. In some yeasts we observed multilayered intracytoplasmic membrane a figure which is not described as far as we know in any yeast. Many vacuoles were frequently observed in the cytoplasm and especially in the center of the oval shaped cells. Bilateral budding which form ascospores is identical for the morphology of this yeast.
Asunto(s)
Candidiasis Bucal/microbiología , Saccharomycetales/ultraestructura , Anciano , Enfermedad Crónica , Femenino , Humanos , Microscopía Electrónica , Periodontitis/microbiología , Saccharomycetales/aislamiento & purificaciónRESUMEN
Methionine sulphoximine (MSO) is a centrally acting neurotoxin which inhibits the glutamate metabolism enzymes and has convulsive properties. Small doses of MSO were administered to rabbits, either intravenously (i.v.) or intracerebroventricularly (ICV), and electron microscopic examination of the cerebellum, the spinal cord and the sciatic nerve was performed on the first day of rabbit hind leg rigid paralysis (myopathy with histological findings resembling myositis), which set in by the 2nd to 4th day after MSO administration. In the cerebellum focal minor alterations were found in the astrocytes (swelling and lucidity, diminution of glycogen granules) and sparsely in the presynaptic terminals (lucidity and clumping), whereas most of the neuron presented a normal appearance. In the spinal cord and in the sciatic nerve a dissociation of the axon from the myelin sheath was evident in a small number of myelinated nerve fibres, along with the appearance of vacuolated spaces. Mitochondrial disorganisation in the axons, as well as glial cell alterations, were also seen. The ultrastructural alterations were non specific, and since they were induced 2 to 4 days after the administration of either minimum doses (i.v.) or of extremely low doses (ICV) of MSO, they may be attributed to the inordinate increase of metabolism during the period of convulsions.
Asunto(s)
Sistema Nervioso Central/efectos de los fármacos , Convulsivantes/farmacología , Metionina Sulfoximina/farmacología , Neurotoxinas/farmacología , Nervio Ciático/efectos de los fármacos , Animales , Sistema Nervioso Central/ultraestructura , Cerebelo/efectos de los fármacos , Cerebelo/ultraestructura , Inyecciones Intravenosas , Inyecciones Intraventriculares , Masculino , Células de Purkinje/ultraestructura , Conejos , Nervio Ciático/ultraestructura , Médula Espinal/efectos de los fármacos , Médula Espinal/ultraestructuraRESUMEN
Tamoxifen (TAM, 0.01 mg/animal, three times a week) and the experimental prolactin-lowering CV 205502 (CV, 1 microgram/animal, daily) were administered prophylactically, alone or combined, to virgin C3H/Sy mice during the early period of promotion in this spontaneous mammary carcinogenesis system (end of 2nd-5th month of age), in order to study their influence on the morphology and evolution of the noncancerous mammary gland during therapy and after treatment cessation. During TAM administration the epithelial cells of the growing part of the gland exhibited myoepithelial- and, late in the treatment period, apoptotic-like features instead of the secretory ones expected, accompanied by intense basement membrane alterations, thickening of the surrounding connective tissue and arrested adipocyte maturation. These effects reversed progressively after drug withdrawal. The epithelial alterations were more intense and longer lasting in the TAM+CV-group, while growth arrest of the glands was observed in both groups parallel to the degree and the duration of these morphological changes. In these groups, tumor incidence was diminished, as expected, but the tumors that developed late after treatment cessation were of low histological differentiation. The above morphological observations show that TAM inhibits noncancerous mammary gland growth during the reproductive period by altering stromal and epithelial differentiation, effects that reverse progressively after treatment discontinuation and are potentiated by a prolactin-lowering agent in this animal study.
Asunto(s)
Envejecimiento/fisiología , Aminoquinolinas/farmacología , Glándulas Mamarias Animales/patología , Neoplasias Mamarias Animales/tratamiento farmacológico , Neoplasias Mamarias Animales/patología , Tamoxifeno/farmacología , Adipocitos/efectos de los fármacos , Adipocitos/patología , Aminoquinolinas/uso terapéutico , Animales , Apoptosis/efectos de los fármacos , Dopaminérgicos/farmacología , Dopaminérgicos/uso terapéutico , Epitelio/efectos de los fármacos , Epitelio/patología , Femenino , Glándulas Mamarias Animales/efectos de los fármacos , Glándulas Mamarias Animales/crecimiento & desarrollo , Ratones , Ratones Endogámicos C3H , Tamoxifeno/uso terapéuticoRESUMEN
In this study the ultrastructure of rat jejunal epithelial cells was examined, following a starvation period of 72 hours and an enteral refeeding period of 12 days, with either Nutrison, Pepti 2000, or Nutri 2000. Most changes occurred in the animals examined immediately after the 72-hour starvation period; these mainly included a significant decrease in microvilli population, occasional cell membrane disintegration, and a usual microvesicular appearance and degranulation of the rough endoplasmic reticulum. No alterations were found in the normally-fed animals (control group). This was also practically the same for the Pepti 2000 group. In the Nutrison group, a small amount of changes were found, while in the Nutri 2000 group many alterations were detected, which nevertheless were fewer than in the starved animals. The results demonstrate that the micromorphological alterations of the intestinal epithelium caused by starvation improve faster when an oligopeptidic formula is provided, which consequently results in faster and better absorption of the nutrients.
Asunto(s)
Proteínas en la Dieta/farmacología , Alimentos Formulados , Mucosa Intestinal/ultraestructura , Oligopéptidos/farmacología , Inanición/patología , Aminoácidos/farmacología , Animales , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/ultraestructura , Epitelio/efectos de los fármacos , Epitelio/ultraestructura , Mucosa Intestinal/efectos de los fármacos , Yeyuno/efectos de los fármacos , Yeyuno/ultraestructura , Masculino , Microvellosidades/efectos de los fármacos , Microvellosidades/ultraestructura , Ratas , Ratas Wistar , Aumento de Peso/efectos de los fármacosRESUMEN
Dental pulp capillaries were studied in human. They were of the continuous type, with the exception of a small number which were of the fenestrated type, located in the vicinity of the odontoblasts. A characteristic morphological peculiarity was found in the endothelial cells. In places there was a large quantity of multi-sized vacuoles. The vacuoles were evidently of pinocytotic origin, and their content was emptied into the extracapillary space. The initiation of their formation was indicated by the creation of cytoplasmic flaps, which could not be characterised as typical pseudopodia, and which in cross sections resembled microvilli. The flaps engulfed a quantity of plasma and then, after bending over, their edge fused with the cell, creating a vacuole. The vacuole, after being moved abluminally, was emptied into the pericapillary area by exocytosis. There was indication that flaps created at the borders of the endothelial cells (flanges) acted likewise, transporting vacuoles through the intercellular spaces. Micropinocytosis, was a distinctly different phenomenon, contributing, to a very small degree, to the intracellular enlargement of the vacuoles. It seems that this vacuolar mechanism of transportation serves an augmented metabolic need of the surrounding tissue.
Asunto(s)
Pulpa Dental/ultraestructura , Endotelio Vascular/ultraestructura , Pinocitosis , Vacuolas/ultraestructura , Adulto , Capilares/ultraestructura , Citoplasma/ultraestructura , Pulpa Dental/irrigación sanguínea , Retículo Endoplásmico/ultraestructura , Exocitosis , Humanos , Microtomía , Fibras Nerviosas/ultraestructuraRESUMEN
It is known that submandibular glands produce serous saliva in the serous demilune cells and mucous saliva in the mucous acinar cells which is a viscous, rich in glycoproteins substance. The aim of this study was the comparative histochemical investigation of acid and neutral salivary glycoproteins in the acinar cells of the submandibular gland in adult and aging rats. Three groups of female Wistar rats were studied: a) young adult rats, 3 months old, b) aged rats 25 months old, c) aged rats 30 months old. Each group included 5 animals. The animals were sacrificed with ether in toxic dose. The submandibular glands were dissected and placed in 10% formaldehyde solution. After fixation they were embedded in paraffin. The paraffin sections were stained with various techniques. We used the: a) Alcian-Blue PH 2,5-Neutral Red b) Periodic-acid/Schiff/Diastase c) Alcian-Blue PH2,5 and Periodic-acid/Schiff/Diastase. We observed that the acinar cells of the aged submandibular glands were filled with acid glycoproteins, while the neutral glycoproteins were localized only in the group of the adult rats. Our results confirm the theory, that lithiasis and chronic inflammations of the submandibular gland, which often happen after the 4th decade of the life, are due to alterations of the mucosubstance composition of the acinar cells.
Asunto(s)
Envejecimiento/metabolismo , Glicoproteínas/análisis , Proteínas y Péptidos Salivales/análisis , Glándula Submandibular/química , Animales , Femenino , Histocitoquímica , Ratas , Ratas WistarRESUMEN
Malformations of the tongue, are structural defects, present at birth and happening during embryogenesis. Developmental anomalies or defects may be major or minor, single or multiple, depending on their size, site and effect. The aim of this study was to present and to describe congenital syndromes which are associated with tongue malformations and to classify these malformations in groups, according to the tongue's clinical manifestations. The most common malformations of the tongue combined with syndromes associated with them, are fully discussed in this review article. Malformations of the tongue which are discussed in this review article, have been classified in the following categories: 1. Aglossia 2. Microglossia 3. Tongue hemiatrophy 4. Tongue hemihypertrophy 5. Macroglossia 6. Long tongue 7. Ankyloglossia 8. Cleft or bifid tongue 9. Syndromes that affect tongue and cannot be classified in a special condition Each category is discussed separately in this article.
Asunto(s)
Lengua/anomalías , Atrofia/congénito , Síndrome de Goldenhar/patología , Humanos , Hipertrofia/congénito , Recién Nacido , Macroglosia/patología , Síndrome , Lengua/patologíaRESUMEN
The development of the tongue begins as known, in the floor of the primitive oral cavity, when the human embryo is four weeks old. More specifically, the tongue develops from the region of the first three or four branchial arches during the period that the external face develops. Malformations of the tongue, are structural defects, present at birth and happening during embryogenesis. The most common malformations are: 1. Aglossia 2. Microglossia, which is always combined with other defects and syndromes, like Moëbius syndrome 3. Macroglossia, which is commonly associated with cretinism, Down's syndrome, Hunter's syndrome, Sanfilippo syndrome and other types of mental retardation 4. Accessory tongue 5. Long tongue 6. Cleft or Bifid tongue, condition very usual in patients with the orodigitofacial syndrome 7. Glossitis Rhombica Mediana, a developmental malformation? 8. Lingual thyroid. Malformations are extensively analysed and discussed.
Asunto(s)
Lengua/anomalías , Anomalías Múltiples/clasificación , Humanos , Anomalías de la Boca/clasificación , Síndrome , Lengua/embriologíaRESUMEN
Peripolar cells are located in the outer layer of the Bowman's capsule. They surround the vascular pole of the renal corpuscle and project into the urinary space. Morphologically they are characterized by the presence of secretory granules within their cytoplasm. In order to study their embryological development, we used 60 C57bl mice embryos (15th to 19th gestational day), 10 newborn mice (2 hours to 6 days old), 10 preadult mice (8-30 days old) and 4 adults (4 months old). Some granular cells, dispersed at the outer and inner layer of the Bowman's capsule, appear on the 17th gestational day. Later, these cells are found around the vascular pole of the renal corpuscle, located exclusively at the outer layer of the Bowman's capsule. Their granules are spherical and variously dense, they are surrounded by a membrane and their number increases progressively with time and reaches a maximum on the 4th postnatal day. Following that, there is a diminution and then their population stabilizes. By the end of the first month, there are only a few such cells (mean number 1 to 2). They become smaller and they always project into the urinary space.
Asunto(s)
Aparato Yuxtaglomerular/embriología , Ratones Endogámicos C57BL/embriología , Animales , Animales Recién Nacidos , Edad Gestacional , Aparato Yuxtaglomerular/ultraestructura , Ratones , MorfogénesisRESUMEN
The fine structure of bronchial epithelium in thirty-six patients, thirty-one men and five women, suffering from chronic obstructive pneumonopathy or bronchial carcinoma was studied. No remarkable alterations were found with electron microscopy, in most non-smokers in contrast to the smokers who presented destruction of the epithelial cells and loss of the cilia or many pathological cilia with an abnormal microtubular configuration and irregular orientation. The severity, however, of the alterations was not related to the severity of smoking and to the presence of bronchial cancer.
Asunto(s)
Bronquios/ultraestructura , Enfermedades Pulmonares/patología , Adulto , Anciano , Bronquios/patología , Neoplasias de los Bronquios/patología , Neoplasias de los Bronquios/ultraestructura , Enfermedad Crónica , Cilios/ultraestructura , Epitelio/patología , Epitelio/ultraestructura , Femenino , Humanos , Masculino , Microscopía Electrónica , Persona de Mediana EdadRESUMEN
After exposing rats to an environment of isobaric hyperoxia, the ultrastructural alterations of the hippocampus were studied. No major alterations were found in the nerve cells. Of importance was the moderate osmiophilia and the spindle-like transformation of the mitochondria. Vacuolated synapses and neuraxons were found, containing amorphous material. Astrocytic perivascular end feet were found vacuolated in many places. Many endothelial cells of the capillaries presented high osmiophilia, which sometimes prevented structural details. Quantitatively, the findings were proportionally related to the time of exposure in the pure oxygen atmosphere (24, 48 and 65 hours).
Asunto(s)
Endotelio Vascular/efectos de los fármacos , Hipocampo/efectos de los fármacos , Oxígeno/toxicidad , Animales , Relación Dosis-Respuesta a Droga , Endotelio Vascular/ultraestructura , Hipocampo/ultraestructura , Masculino , Ratas , Ratas Endogámicas , Factores de TiempoRESUMEN
The few reported cases of sclerosing cholangitis following removal of an echinococcus cyst are thought to be a consequence of the chemical action of formalin used for sterilization of the residual cavity. The aim of this study was to assess this hypothesis. We injected 0.15ml of 2% buffered formalin solution into the central hepatic lobe of five rats, after a midline laparotomy. At 6, 12, 18 and 24 weeks after formalin injection all rats were reoperated upon and a sample of hepatic parenchyma from both the central and the left hepatic lobe was obtained for microscopic evaluation. Our findings, dilatation of portal tracts and bile canaliculi, thickening of the pericanalicular cytoplasm, portal and periportal inflammatory cell infiltration and fibrosis and enlargement of the perisinusoidal space of Disse, suggest that 2% formalin solution leads to the development of essential phenomena of cholestasis and sclerosing cholangitis in the rat, so thus it should be avoided in liver hydatid disease surgery.