RESUMO
Background: During physiological root resorption of deciduous teeth, apoptotic cell death triggered by physiological processes might play a role in physiological root resorption in addition to collagen destruction. Little information has been obtained about the sequence of events and the mechanism responsible for the physiological death of pulp tissue cells. Aim: This study evaluated apoptotic cell death in the pulp tissue of deciduous teeth that showed various levels of physiological root resorption. The role of apoptosis in pulp tissue elimination during the physiological resorption of deciduous teeth was also examined. Materials and Methods: For orthodontic reasons, 12 healthy permanent teeth and the pulp of 34 healthy deciduous teeth showing signs of early and advanced root resorption were extracted. To detect apoptotic cells in the pulp tissue, the terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL) method and transmission electron microscopy (TEM) were used. The apoptotic index (AI) values of the study groups were determined using the TUNEL method. This technique required calculating the Apoptag positive(+) fibroblast cell ratio in accordance with the total number of cells. Results: No statistically significant differences were found for the AI values of each study group (p>0.05). Apoptosis was detected in the vascular endothelial cells, the mononuclear inflammatory cells, and the odontoblasts of the connective pulp tissue. In the pulp tissue, evaluated using TEM, various pulp cells were observed at distinct stages of apoptosis. Conclusion: The similarity between the AI values for both study groups suggested that in early and advanced stages of resorption, apoptosis may contribute to the regulation of the pulp cell population in a way that does not relate to the physiological process of deciduous teeth root resorption.
Assuntos
Reabsorção da Raiz , Humanos , Células Endoteliais , Apoptose , Leucócitos , Dente DecíduoRESUMO
OBJECTIVE: The aim of the present study was to evaluate the time-dependent histopathologic changes in both ovaries and to determine the time-dependent levels of plasma interleukin 6 (IL-6) after unilateral ovarian torsion. MATERIALS AND METHODS: An experimental animal study included 48 female Sprague-Dawley rats which were distributed to six groups: control group (Group 1), sham-operated control group (Group 2), and four unilateral ovarian torsion groups with torsion duration of three, six, 12, and 24 hours (Group 3, 4, 5, and 6, respectively). Histopathologic criteria (follicular degeneration, vascular congestion, hemorrhage, inflammatory cell infiltration, and total tissue damage score) were evaluated in both ovaries, and plasma IL-6 levels were measured. RESULTS: At 24 hours after torsion began, mean total tissue damage score was similar between ovaries that had torsion and contralateral ovaries. Mean plasma IL-6 level did not change during the 24 hours after torsion began (p = 0.584). CONCLUSIONS: In addition to ovaries that had torsion, histopathologic abnormalities also occurred in contralateral ovaries. These results suggest that contralateral ovaries are not quiescent after unilateral ovarian torsion. Plasma IL-6 levels did not change significantly during the 24 hours after ovarian torsion began, resulting in a limitation of its diagnostic use in the early course of the disease.
Assuntos
Interleucina-6/sangue , Doenças Ovarianas/patologia , Ovário/patologia , Anormalidade Torcional/patologia , Animais , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Doenças Ovarianas/sangue , Ovário/anormalidades , Ratos , Ratos Sprague-Dawley , Anormalidade Torcional/sangueRESUMO
OBJECTIVE: This study was designed to test the effects of different types of preconditioning and postconditioning methods on spinal cord protection following aortic clamping. METHODS: The animals (rabbits) were divided into sham-operated, ischemic preconditioning, remote ischemic preconditioning, simultaneous aortic and ischemic remote preconditioning, and ischemic postconditioning groups. After neurological evaluations, ultrastructural analysis and immunohistochemical staining for caspase-3 were evaluated after 24 h following ischemia. RESULTS: The neurological outcomes of the remote ischemic preconditioning (4.2 ± 0.4) and ischemic postconditioning (4.6 ± 0.8) groups were significantly improved when compared with the ischemia group (2.2 ± 04). The immunohistochemical analysis revealed that the lowest percentage of apoptosis was in-group ischemic preconditioning at 12.5 ± 30.6%. In the comparison of intracellular edema in an ultrastructural analysis, the ischemic preconditioning and ischemic postconditioning groups had significantly lower values than the ischemia group. CONCLUSION: The conditioning methods attenuate ischemia-reperfusion injury for spinal cord injury. Ischemic and remote preconditioning and also postconditioning methods are simple to perform and inexpensive.
Assuntos
Aorta Abdominal/cirurgia , Artéria Axilar/cirurgia , Pós-Condicionamento Isquêmico/métodos , Precondicionamento Isquêmico/métodos , Traumatismo por Reperfusão/prevenção & controle , Isquemia do Cordão Espinal/prevenção & controle , Medula Espinal/irrigação sanguínea , Animais , Aorta Abdominal/fisiopatologia , Apoptose , Artéria Axilar/fisiopatologia , Caspase 3/metabolismo , Constrição , Modelos Animais de Doenças , Atividade Motora , Coelhos , Fluxo Sanguíneo Regional , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Medula Espinal/metabolismo , Medula Espinal/ultraestrutura , Isquemia do Cordão Espinal/metabolismo , Isquemia do Cordão Espinal/patologia , Isquemia do Cordão Espinal/fisiopatologia , Fatores de TempoRESUMO
OBJECTIVE: To compare the percentage and ultrastructure of normal and abnormal granulosa cells and their effect on fertilization and pregnancy rate between gonadotropin releasing hormone (GnRH) agonist and antagonist treatment. MATERIALS AND METHODS: In this study, granulosa cells obtained from 22 women undergoing in vitro fertilization (IVF) treatment due to unexplained infertility with either with GnRH agonist (n = 11) or GnRH antagonist (n = 11) were evaluated by light and electron microscopy. RESULTS: GnRH agonist and antagonist therapy was found to have no effect in terms of abnormal granulosa cell percentage (0.0679 ± 0.08977 vs 0.0481 ± 0.05164; p > 0.05), fertilization [85 (45-90) vs 75 (64-93)] and pregnancy rate (37% vs 46%). Light microscopic observations showed similar features of normal cells of agonist and antagonist-treated cells. Ultrastructural evaluation also revealed that there was no difference between cells of two treatment groups. CONCLUSION: Both GnRH agonist and antagonist treatment for ovarian stimulation may have similar effects on granulosa cells at the morphological and ultrastructural level, as well as on fertilization and pregnancy rates.
Assuntos
Fármacos para a Fertilidade Feminina/farmacologia , Fertilização in vitro , Hormônio Liberador de Gonadotropina , Células da Granulosa/ultraestrutura , Indução da Ovulação , Adulto , Feminino , Hormônio Liberador de Gonadotropina/agonistas , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Células da Granulosa/efeitos dos fármacos , Humanos , Gravidez , Taxa de GravidezRESUMO
PURPOSE: To evaluate intraovarian histologic changes caused by polypropylene and silk sutures that commonly are used in ovarian suspension. MATERIALS AND METHODS: Twenty-four female rats were randomly allocated to three study groups: a sham group receiving no ovarian suspension; the other two groups that had right ovarian suspension with polypropylene and silk sutures. At 90 days after surgery, the histologic changes and ovarian weight reduction in the suspended ovaries and severity of pelvic adhesions were evaluated. RESULTS: There were no differences between study groups in focal inflammation, cystic structures, or vascularity. Adhesion severity and ovarian weight reduction in suspended ovaries and cysts around the suspended ovary were significantly greater in the silk than sham group. The frequency of hematoma within the suspended ovary was significantly greater in the polypropylene than sham group. CONCLUSIONS: Polypropylene suture caused less adhesion severity or ovarian weight reduction than silk suture. This suggests that polypropylene suture may be the better suture for ovarian suspension procedures.
Assuntos
Ovário/cirurgia , Suturas/efeitos adversos , Animais , Feminino , Humanos , Ovário/patologia , Polipropilenos , Ratos , Ratos Sprague-Dawley , Aderências Teciduais/etiologiaRESUMO
OBJECTIVES: Dyslipidemia is a risk factor for post- transplant diabetes mellitus, especially in patients who are taking tacrolimus. Although lipotoxicity of dyslipidemia leads to ß-cell failure, the handling of lipids by ß cells is a mystery in molecular endocrinology. Likewise, lipid droplet homeostasis is appreciated as a key component of lipid metabolism in cells like hepatocytes, but its role in ß cells remains to be elucidated. MATERIALS AND METHODS: To evaluate the morphologic changes in ß cells with special focus on lipid droplets, we evaluated electron micrographs under metabolic stress conditions of glucotoxicity, lipotoxicity, and glucolipotoxicity in isolated rat insulinoma INS-1E ß cells. Cells were treated with palmitic acid (0.5 mM), glucose (33 mM), or both for 16 hours, after which morphologic changes were observed with an electron microscope. RESULTS: Many lipid droplets were observed in the cytoplasm of healthy ß cells in the control group (no treatment). Lipid droplets were also visible in the cytosol, and the cytoplasm was rich in organelles and insulin vesicles under high glucose stimulation. However, after treatment with palmitic acid, almost no lipid droplets were observed. Endocrine vesicles were also depleted, with severe morphologic disruption of other organelles. Under glucolipotoxic conditions, ß cells showed a decreased number of lipid droplets and insulin vesicles compared with controls. CONCLUSIONS: Lipid droplet dynamics seemed important in the homeostasis of ß-cell metabolism. In this preliminary study, healthy ß cells appeared rich in lipid droplets under normal conditions. However, lipotoxicity depleted and glucolipotoxicity decreased the number of lipid droplets in ß cells. Because dyslipidemia causing lipotoxicity is one of the most frequent metabolic problems in transplant patients and increases risk of posttransplant diabetes mellitus, understanding the mystery of lipid droplets in ß cells and the pathophysiology of diabetes in transplant patients is important, especially for those taking tacrolimus.
RESUMO
The increase in autoimmune diseases in recent years has drawn attention back to the thymus, with new approaches to improve and/or restore immune function being investigated. As the primary lymphoid organ responsible for functional T cell development, studies on the pre-/post-natal development of this organ and T lymphocytes in human and other species are of special interest. During our screening studies we observed structures that had not been described or mentioned previously, and named them "epitheliostromal sheaths". Associated with these unique structures were also small attached lobules (possibly reflecting the maturational stages of thymic lobules), which the authors consider as markers of histogenesis and the growth of the organ during early childhood; these findings are thus presented to researchers in this field. Approximately 1000 sections prepared from infantile thymic tissues of partial biopsy specimens were immunostained and examined. Specimens were taken from ten patients (with informed consent) in the age range of 4-9 years who underwent surgery due to congenital cardiovascular anomalies but were otherwise normal. Digital images of interest were captured to describe them in detail. Determining the immunophenotype of the compartments in these newly developing lobules assisted us greatly in defining compartments and their growth order. In summary, our findings suggest a niche-based thymus growth mechanism during childhood. We presented our findings, hoping to provide additional insight to researchers aiming to restore thymus function in adulthood and improve its immunological functions.
Assuntos
Desenvolvimento Infantil , Timo/crescimento & desenvolvimento , Animais , Biópsia , Diferenciação Celular/fisiologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Linfócitos T/fisiologiaRESUMO
OBJECTIVES: Colistin is a vital antibiotic used in multidrug-resistant infections. Its most important side effect is nephrotoxicity. Colistin is a weak acid. This study aims to evaluate whether urine alkalinization is protective in the nephrotoxicity of colistin. METHODS: Twenty-eight male Sprague-Dawley rats were divided into groups. Group I (n = 4) was injected with intramuscular distilled water twice a day for 7 days. Group II (n = 8) was injected with 750,000 IU/kg/day colistin for 7 days. Group III (n = 8) was injected with the same dose of colistin after their urinary pH was ≥7 through the addition of bicarbonate in their drinking water. Group IV (n = 8) was injected with the same dose of colistin after their urine density fell below 1010 through the addition of NaCl molds in their food and 12.6 mg/L NaCl in their drinking water. RESULTS: According to tubular degenerations (scored 0-5), group I scored 0, group II scored 4.25, group III scored 2, and group IV scored 1.5. In groups III and IV, protection was achieved (p = 0.001). The bicarbonate group was not superior to the NaCl group (p = 0.789). In transmission electron microscopy, group III had more microvilli integrity and autophagic vacuoles compared to group IV. Group IV had mitochondrial swelling and cristae lysis. A lower urine density was related to lower tubular scores (p = 0.001). CONCLUSIONS: Colistin was highly nephrotoxic without protection. Light microscopy findings revealed that urinary alkalinization and NaCl hydration were similarly protective. Urine alkalinization further prevents ultrastructural changes as revealed by electron microscopy.
Assuntos
Antibacterianos/toxicidade , Bicarbonatos/farmacologia , Colistina/toxicidade , Nefropatias/prevenção & controle , Cloreto de Sódio/farmacologia , Urina/química , Animais , Concentração de Íons de Hidrogênio , Rim/efeitos dos fármacos , Rim/patologia , Rim/ultraestrutura , Nefropatias/induzido quimicamente , Nefropatias/patologia , Masculino , Microscopia Eletrônica de Transmissão , Ratos Sprague-DawleyRESUMO
We investigated the microscopic structure of transverse sections of the oculomotor, trochlear and abducens nerves of Arabian foals using stereological methods. Bilateral nerve pairs from 2-month-old female Arabian foals were analyzed. The tissues were embedded in plastic blocks, then 1 µm thick sections were cut and stained with osmium tetroxide and methylene blue-azure II. Stereology was performed using light microscopy. Morphometry showed that the right and left pairs of nerves were similar. The transverse sectional areas of the oculomotor, trochlear and abducens nerves were 1.93 ± 0.19 mm2, 0.32 ± 0.06 mm2 and 0.70 ± 0.08 mm2, respectively. The oculomotor nerve exhibited a significantly greater number of myelinated axons (16755 ± 1279) and trochlear (2656 ± 494) and the abducens nerves (4468 ± 447). The ratio of the axon diameter to myelinated nerve fiber diameter was 0.58, 0.55 and 0.55 for the oculomotor, trochlear and abducens nerves, respectively. Of the three nerves studied, the abducens nerve exhibited the greatest nerve fiber area, myelin area, nerve and axon diameters, and myelin thickness. The ratio of small myelinated nerve fibers was greatest in the oculomotor nerve.
Assuntos
Nervo Abducente/metabolismo , Axônios/metabolismo , Bainha de Mielina/metabolismo , Fibras Nervosas Mielinizadas/metabolismo , Nervo Oculomotor/metabolismo , Animais , Feminino , Cavalos , Microscopia/métodosRESUMO
PURPOSE: To investigate the effect of antithrombin III (AT III) on retinal ischemia/reperfusion (I/R) injury in rats. METHODS: The study was carried out on 10 Wistar albino rats (20 eyes) and four-vessel occlusion method was employed to induce retinal ischemia in this study. Rats were divided into two groups: Group I (control group, 10 eyes) and Group II (AT III, 10 eyes). In both groups, vertebral arteries were occluded bilaterally an electric needle coagulator under an operating microscope. A total of 48 hours after the initial procedure, the rats were re-anesthetized and both common carotid arteries were clamped to interrupt blood flow. In Group II, rats were injected intravenously with 250 U/kg of AT III 5 minutes before the induction of ischemia. Duration of ischemia was 30 minutes. At the end of this period, clamp was removed for the reperfusion of the eye for 4 hours. Following the reperfusion period, the animals were killed by decapitation. Retinal sections were evaluated under light and electron microscope. The signs of I/R injury at the microscopic level, i.e., cellular degeneration, vacuolization between retinal layers, increase in the retinal thickness due to edema, mononuclear cell infiltration, and apoptotic cells, were recorded for each group. RESULTS: Retinal sections obtained from the rats in the AT III group revealed a well preserved retinal structure. When average thickness values of the two groups were compared to each other, the difference was significant with respect to inner nuclear and inner plexiform layers indicating increased retinal thickness values in Group I due to tissue edema resulting from I/R injury. Similarly, mononuclear cell infiltration and apoptotic cell counts were found to be significantly higher in control group compared to AT III group showing the inhibitory effect of AT III on leukocyte infiltration and apoptotic cell death in rat retina. CONCLUSIONS: Antithrombin III attenuated I/R injury in rat retina.
Assuntos
Antitrombina III/uso terapêutico , Isquemia/prevenção & controle , Traumatismo por Reperfusão/prevenção & controle , Doenças Retinianas/prevenção & controle , Vasos Retinianos/efeitos dos fármacos , Inibidores de Serina Proteinase/uso terapêutico , Animais , Apoptose , Contagem de Células , Modelos Animais de Doenças , Isquemia/patologia , Leucócitos/ultraestrutura , Microscopia Eletrônica , Ratos , Ratos Wistar , Traumatismo por Reperfusão/patologia , Doenças Retinianas/patologia , Vasos Retinianos/ultraestruturaRESUMO
AIM: To determine the ultrastructural effects of sildenafil on the female genital organs. METHODS: Twenty female cycling Wistar albino rats weighing 250+/-20 g were randomly divided into two groups of 10 each. Rats of one group were gavaged with 0.5 mg.kg(-1).d(-1) of sildenafil 3 days in a week for 4 weeks and the other served as the controls. After cessation of treatment animals were sacrificed by cervical dislocation under methoxyflurane anaesthesia. The clitoris, vagina, uterus and bartholin glands were taken at the estrous and were fixed with 10% formalin solution for light microscopy and 2.5% glutaraldehyde and osmic acid for electron microscopy. RESULTS: Under the light microscope, the fibrocollageous tissue was found increased, the capillaries enlarged and the connecting tissue elements increased in the corpus cavernosum in the treated group. On electron microscopy, increased connective tissue, fibroblasts with notched nucleus, shorten immature collagen fibers without striation were seen. Abundant foldings and penetration with collagen bundles were observed in the basal membrane. Large connection complexes, especially gap junctions among the wide capillary endothelial cells were observed. CONCLUSION: There are evident histological changes due to sildenafil citrate in female rat corpus cavernosum. The clitoris and bartholin glands were the most effected organs. While the histopathological changes of clitoral tissue could be expected, an increase in the mass of bartholin gland was surprising.
Assuntos
Glândulas Vestibulares Maiores/efeitos dos fármacos , Clitóris/efeitos dos fármacos , Piperazinas/farmacologia , Vasodilatadores/farmacologia , Animais , Glândulas Vestibulares Maiores/irrigação sanguínea , Glândulas Vestibulares Maiores/ultraestrutura , Capilares/ultraestrutura , Clitóris/irrigação sanguínea , Clitóris/ultraestrutura , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/ultraestrutura , Feminino , Microscopia Eletrônica , Purinas , Ratos , Ratos Wistar , Citrato de Sildenafila , Sulfonas , Útero/efeitos dos fármacos , Vagina/efeitos dos fármacos , Vagina/ultraestruturaRESUMO
Renal oncocytoma is one of the most unusual benign lesions, which presents as a complicated mass resulting in a diagnostic and therapeutic dilemma. A new case of renal oncocytoma in a 13-year-old boy is presented. The clinocopathologic features of this rare entity are discussed, with special emphasis on diagnosis and treatment. There are no specific presumptive clinical and laboratory findings, including tumor markers, ploidy analysis, and imaging techniques that distinguish oncocytoma from other renal masses. The most important diagnostic aid is to bear this entity in mind when a child presents with an unexplained renal mass. Frozen section biopsies followed by partial nephrectomy are mandatory for the appropriate treatment after excluding bilateral or multifocal occurrence.
Assuntos
Adenoma Oxífilo/diagnóstico , Adenoma Oxífilo/cirurgia , Neoplasias Renais/diagnóstico , Neoplasias Renais/cirurgia , Nefrectomia/métodos , Adolescente , Biópsia/métodos , Humanos , MasculinoRESUMO
Talon cusp is a tooth anomaly that affects both the primary and the permanent dentitions. However, the occurrence of this anomalous cusp is rather infrequent in the primary dentition. Only 7 cases of bilateral talon cusps affecting the primary teeth have been reported in the dental literature. This is a case report of bilateral talon cusps on primary maxillary central incisors whose histologic evaluation revealed the existence of pulpal tissue in the anomalous cusps.
Assuntos
Incisivo/anormalidades , Coroa do Dente/anormalidades , Polpa Dentária/anormalidades , Humanos , Incisivo/diagnóstico por imagem , Lactente , Masculino , Maxila , Fotografia Dentária , RadiografiaRESUMO
OBJECTIVES: Extracorporeal shockwave lithotripsy (ESWL) has been applied in sialolithiasis as a new treatment modality. The aim of this experimental study is to investigate the local effects of electrohydraulic ESWL applied to the right submandibular gland of the rats. METHODS: This prospective study was conveyed in four groups; groups I, II, III and IV; each group consisting of 20, 20, 18 and 9 rats, respectively, with a randomized distribution. Groups I, II, III and IV received 250, 500, 1000 and 2000 shock waves at 14-16 kV (average 15.1 kV), respectively, to the right submandibular glands on the 0th day. In groups I, II, III, right submandibular glands of the rats were removed on the 0th, 1st, 7th and 15th days; in group IV, this procedure could be managed only on the 0th and 7th days. Light and electron microscopic evaluation were assessed. Using the light microscopic changes, severity of damage score of the glands (SDS) was found. Statistical analysis was done using SDSs. RESULTS: Light and electron microscopic observations have shown that the damage produced by the shock waves were confined to focal areas in the acinar cells (AC), granulated convoluted tubule (GCT) cells and blood vessels at all doses applied. Vacuolization in the cytoplasms of the AC and GCT cells, disintegration of membranes, alteration in the cytoplasmic organization, swelling of the mitochondria and loss of the features were observed on electron microscopy. Increase in the secretion rate; stasis and dilatation in the blood vessels; blebbing and loss of features in the cytoplasm of the endothelial cells were observed. According to the result of the statistical analysis using SDSs; at 250 shock wave dose, a statistically significant difference between the SDSs of the days (0th, 1st, 7th and 15th) was found (P<0.05). The SDS on the 0th day was found to have the lowest value among the other days. And also a statistically significant difference was found on the 0th day between the SDSs at doses of 250, 500, 1000 and 2000 shock waves (P<0.05). The SDS at 250 and 500 shock waves was found to have the lower value than the SDS at the 2000 shock wave. It was observed that produced damage was less prominent by small doses (250, 500 doses) initially (0th day). Electrohydraulic ESWL caused a "patchy type" generalized pathology on submandibular glands of the rats and damaged focal areas were widespread all through the gland from the 1st day on. CONCLUSION: Formation of the damage was concluded to be related to the direct effect of the shock waves rather than the dose used. Electrohydraulic lithotripters are not suitable for sialolithiasis because of the focus problems, local tissue damage and the risk of the damage to the adjacent structures.
Assuntos
Litotripsia , Cálculos das Glândulas Salivares/terapia , Doenças da Glândula Submandibular/terapia , Glândula Submandibular/ultraestrutura , Animais , Litotripsia/métodos , Masculino , Microscopia Eletrônica , Ratos , Ratos Wistar , Cálculos das Glândulas Salivares/patologia , Glândula Submandibular/patologia , Doenças da Glândula Submandibular/patologiaRESUMO
We examined the expression of various CD coded or not yet defined antigens in human thymus samples using indirect immunoperoxidase and immunoflourescent techniques. Data obtained are presented in concurrence with Clusters of Thymic Epithelial Staining (CTES) classification for various monoclonal antibodies recognizing CD antigens (CD1, CD1a, CD6, CD9, CD14, CD16, CD29, CD30, CD32, CD44, CD45RB, CD47, CD48, CD49a, CD49b, CD49c, CD49d, CD49e, CD49f, CD51, CD53, CD54, CD56, CD57, CD63, CD85, CD95, CD98, CD102, CD103, CD106, CD109, CD146, CD147, CD148, CD151, CD152, CD158a, CD158b, CD164, CD165, CD166) and for monoclonal antibodies 1B10, 5G7, A4, BD46, BLTZ, HP1C5, IND.64, M72, WU947 whose specifities are not yet defined. Some of the mAbs such as CD49f, IND.64 and BD46 are detected as good markers for specific cell types or compartments. Significance of the presence of these antigens on thymic epithelial cells at certain locations is briefly discussed.
Assuntos
Antígenos CD/análise , Células Epiteliais/imunologia , Linfócitos T/imunologia , Timo/imunologia , Adolescente , Anticorpos Monoclonais , Antígenos CD/classificação , Criança , Pré-Escolar , Cardiopatias Congênitas/cirurgia , Humanos , Reprodutibilidade dos TestesRESUMO
In this study we examined the chorionic villi of 5 normal human placentas at 12-14 weeks of gestation ultrastructurally with regard to differentiation of the vascular components. The aim of the present report is to discuss the factors influencing vasculogenesis (in situ formation of blood vessels) at the ultrastructural level. Our observations have led us to think that the cytotrophoblast influences vasculogenesis in human chorionic villi. Mesenchymal-preendothelial cell groups were always found in very close association with the cytotrophoblast at the periphery of the villi, forming blood vessels. The cytotrophoblast probably attracts mesenchymal cells towards the margin of the villi by secreting vascular endothelial growth factor (VEGF). Once cells attach to the trophoblastic basement membrane they begin to differentiate into endothelial cells. This close structural relation between two cell types (cytotrophoblast and mesenchymal cells) may not be the only mechanism controlling vasculogenesis, but it seems to be one of the factors influencing the differentiation of mesenchymal cells into the endothelial cells of blood vessels in early human chorionic villi.
Assuntos
Vasos Sanguíneos/ultraestrutura , Vilosidades Coriônicas/irrigação sanguínea , Vilosidades Coriônicas/ultraestrutura , Neovascularização Fisiológica , Primeiro Trimestre da Gravidez , Vasos Sanguíneos/fisiologia , Vilosidades Coriônicas/fisiologia , Amostra da Vilosidade Coriônica , Feminino , Humanos , Mesoderma/ultraestrutura , Microscopia Eletrônica , Gravidez , Trofoblastos/ultraestruturaRESUMO
Presence of extracellular cystic cavities in the thymus of many vertebrates has long been known. Various forms of such structures in human thymus were observed and examined thoroughly on immunostained and serial semithin sections. We grouped these structures into five categories according to their most characteristic features. The lympho-epithelial content of the cysts clearly reflected the structural features and antigenic profile of thymic cortical parenchyma in both elongated and ovo-spherical cysts. Our findings suggest that the various types of cystic structures observed in human thymus may represent maturational stages of classical Hassal's corpuscles. Presence of cortical lympho-epithelial content and its gradual replacement with debris material also suggests a unique mechanism of thymocyte disposal.
Assuntos
Cisto Mediastínico/etiologia , Timo/citologia , Adolescente , Anticorpos Monoclonais , Antígenos CD/análise , Criança , Pré-Escolar , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Humanos , Técnicas Imunoenzimáticas , Cisto Mediastínico/metabolismo , Cisto Mediastínico/patologia , Timo/metabolismoRESUMO
OBJECTIVE: This study aimed to determine the effect of radiofrequency radiation generated by 900 and 1800 MHz Global System for Mobile Communications sources on cochlear development in the rat model. METHODS: Eight pregnant albino Wistar rats were divided into three groups: control, 900 MHz and 1800 MHz. The latter two groups of pregnant rats were exposed to radiofrequency radiation for 1 hour per day starting on the 12th day of pregnancy until delivery. The rats in the control, 900 MHz and 1800 MHz groups gave birth to 24, 31 and 26 newborn rats respectively. Newborn rats in the 900 MHz and 1800 MHz groups were exposed to radiofrequency radiation for 1 hour per day for 21 days after delivery. Hearing evaluations of newborn rats were carried out using distortion product otoacoustic emissions testing. Eight newborn rats were randomly selected from each group for electron microscopic evaluation. RESULTS: Distortion product otoacoustic emission tests revealed no significant difference among the groups, but electron microscopic evaluation revealed significant differences among the groups with regard to the number of normal, apoptotic and necrotic cells. CONCLUSION: The findings indicated cellular structural damage in the cochlea caused by radiofrequency radiation exposure during cochlear development in the rat model.
Assuntos
Telefone Celular , Doenças Cocleares/etiologia , Emissões Otoacústicas Espontâneas/efeitos da radiação , Efeitos Tardios da Exposição Pré-Natal/etiologia , Ondas de Rádio/efeitos adversos , Animais , Animais Recém-Nascidos , Cóclea/patologia , Cóclea/efeitos da radiação , Cóclea/ultraestrutura , Doenças Cocleares/embriologia , Modelos Animais de Doenças , Feminino , Masculino , Microscopia Eletrônica , Gravidez , Radiometria/métodos , Ratos WistarRESUMO
OBJECTIVE: The aim of this study was to evaluate the effects of bone marrow-derived mesenchymal stem cell and bone marrow elements on the healing of meniscal tears. METHODS: This study was performed on twelve, 2-year-old male Tahirova sheep. In each subject, one knee was used for experiment purposes and the other knee was used as a control. After creating a longitudinal full-thickness tear in the red-white zone of the medial meniscus, aspirated autologous bone marrow material was injected into the tear site in the experiment group. The control group received no intervention for secondary healing. RESULTS: In the macroscopic evaluation of meniscus, a bridging reparation tissue and adhesion were observed between the rims of the tear in the experiment group. There was no statistical difference in collagen fibril formation between the groups (p=0.16). There was significantly more neovascularization in the experiment group than the control group (p=0.003). The cell count was also a significantly higher in the experiment group (p=0.004) and formation of cartilage plaques was more frequent in the experiment group (p=0.016). There was no evidence suggesting intrinsic repair in the meniscus of control group by light and electron microscopy. CONCLUSION: An injection of bone marrow into the meniscus tear site improves healing in a meniscal tear model as demonstrated by both light and electron microscopic findings.
Assuntos
Transplante de Medula Óssea , Injeções Intra-Articulares , Traumatismos do Joelho/terapia , Lesões do Menisco Tibial , Animais , Transplante de Medula Óssea/métodos , Modelos Animais de Doenças , Traumatismos do Joelho/patologia , Masculino , Meniscos Tibiais/patologia , Carneiro Doméstico , Transplante Autólogo , Resultado do Tratamento , CicatrizaçãoRESUMO
Statins show antiproliferative activity in various cancer cells. The aim of this study was to evaluate the effects of rosuvastatin treatment on papillary thyroid carcinoma. The papillary thyroid carcinoma (B-CPAP) and normal (Nthy-ori 3-1) thyroid cell lines were treated with rosuvastatin at 12.5, 18.5, 25, 50, 100, and 200 µM concentrations. After 48 and 72 h of rosuvastatin treatment, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, Ki-67 immunolabeling, FACS analysis, electron microscopy, caspase-3, and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) analysis were performed. Decreased cell viability and G1 phase arrest were detected in papillary thyroid cell line treated with rosuvastatin. Positive immunoreactivity of Ki-67 and dose-dependent increase in S phase on Nthy-ori 3-1 cells were also detected. B-CPAP cells showed intense vacuolisation and autophagosomes with low concentrations and 48 h incubations, while Nthy-ori 3-1 cells showed these changes at higher concentrations. A decrease in the percentage of cells showing autophagy was determined with increasing concentrations of rosuvastatin in B-CPAP cells. Rosuvastatin treatment also caused a dose- and time-dependent increase in caspase-3 activity and apoptotic index by TUNEL assay in B-CPAP cells compared with the Nthy-ori 3-1 cells. Apoptotic cells with nuclear condensation and fragmentation were observed in B-CPAP cell line. Rosuvastatin induced autophagic changes in B-CPAP papillary thyroid cancer cells in lower doses and caused a shift from autophagy to apoptosis. Rosuvastatin may be an alternative treatment for refractory papillary thyroid cancer. Further in vivo studies are necessary to clarify the effects of rosuvastatin in papillary thyroid carcinoma and the clinical implications of rosuvastatin treatment.