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1.
Syst Biol Reprod Med ; 64(4): 283-290, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29718716

RESUMO

The presence of smooth endoplasmic reticulum aggregates (SERa) in the ooplasm is considered as the most severe oocyte dysmorphism due to its serious and potentially lethal outcomes in offspring. In the present case report, a couple underwent their first intracytoplasmic sperm injection (ICSI) cycle using a gonadotrophin releasing hormone (GnRH) antagonist protocol, followed by fetal ultrasound scanning and amniocentesis. SERa were observed in all oocytes retrieved. A singleton pregnancy was established. The second trimester fetal ultrasound scan revealed a female fetus with overlapping fingers in both hands, and amniocentesis was performed for the detection of chromosomal abnormalities. Comprehensive genetic analysis with the combined use of array-comparative genomic hybridization (CGH), fluoresence in situ hybridization (FISH) and conventional cytogenetics revealed a complex chromosome rearrangement (CCR) involving three break points on two chromosomes, resulting in a reciprocal translocation with a cryptic 2q31 deletion. A week following amniocentesis, there was rupture of amniotic membranes and a stillborn was delivered. This is the first case in the literature to report a CCR with concomitant 2q31 deletion resulting in a well-defined and clinically recognizable contiguous gene syndrome with an abnormal phenotype in a fetus arising from a cohort of oocytes affected by SERa. It is suggested that fertilization and transfer of oocytes with SERa should be avoided, until further research establishes whether there is a causal relationship between the presence of SERa and chromosomal abnormalities in the resulting fetus. ABBREVIATIONS: SER: smooth endoplasmic reticulum; ICSI: intracytoplasmic sperm injection; GnRH: gonadotrophin releasing hormone; CGH: comparative genomic hybridization; FISH: fluoresence in situ hybridization; FSH: follicle stimulating hormone; hCG: human chorionic gonadotrophin; OHSS: ovarian hyperstimulation syndrome; IVF: in vitro fertilization; MII: metaphase II; GV: germinal vesicle; CCR: complex chromosome rearrangement.


Assuntos
Aberrações Cromossômicas , Retículo Endoplasmático Liso/patologia , Oócitos/patologia , Adulto , Feminino , Humanos , Masculino , Injeções de Esperma Intracitoplásmicas
2.
J Physiol Biochem ; 74(4): 531-538, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29470816

RESUMO

Squalene is the main unsaponifiable component of virgin olive oil, the main source of dietary fat in Mediterranean diet, traditionally associated with a less frequency of cardiovascular diseases. In this study, two experimental approaches were used. In the first, New Zealand rabbits fed for 4 weeks with a chow diet enriched in 1% sunflower oil for the control group, and in 1% of sunflower oil and 0.5% squalene for the squalene group. In the second, APOE KO mice received either Western diet or Western diet enriched in 0.5% squalene for 11 weeks. In both studies, liver samples were obtained and analyzed for their squalene content by gas chromatography-mass spectrometry. Hepatic distribution of squalene was also characterized in isolated subcellular organelles. Our results show that dietary squalene accumulates in the liver and a differential distribution according to studied model. In this regard, rabbits accumulated in cytoplasm within small size vesicles, whose size was not big enough to be considered lipid droplets, rough endoplasmic reticulum, and nuclear and plasma membranes. On the contrary, mice accumulated in large lipid droplets, and smooth reticulum fractions in addition to nuclear and plasma membranes. These results show that the squalene cellular localization may change according to experimental setting and be a starting point to characterize the mechanisms involved in the protective action of dietary squalene in several pathologies.


Assuntos
Membrana Celular/metabolismo , Dieta Mediterrânea , Modelos Animais de Doenças , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Membrana Nuclear/metabolismo , Esqualeno/uso terapêutico , Animais , Transporte Biológico , Membrana Celular/patologia , Vesículas Citoplasmáticas/metabolismo , Vesículas Citoplasmáticas/patologia , Citosol/metabolismo , Citosol/patologia , Dieta Hiperlipídica/efeitos adversos , Dieta Ocidental/efeitos adversos , Retículo Endoplasmático Rugoso/metabolismo , Retículo Endoplasmático Rugoso/patologia , Retículo Endoplasmático Liso/metabolismo , Retículo Endoplasmático Liso/patologia , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/patologia , Metabolismo dos Lipídeos , Fígado/patologia , Masculino , Camundongos Knockout para ApoE , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Membrana Nuclear/patologia , Coelhos , Especificidade da Espécie , Esqualeno/metabolismo
3.
Ultrastruct Pathol ; 42(2): 108-115, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29424579

RESUMO

Nevirapine (NVP) therapy is associated with a high risk of serious liver injury and skin rash. Treatment of Brown Norway rats with NVP causes an immune-mediated skin rash. Even though NVP does not cause serious liver injury in wildtype animals, incubation of hepatocytes with NVP leads to the release of presumably danger-associated molecular pattern molecules (DAMPs), which activate macrophages. In this study, we examined the liver biopsies of Brown Norway rats treated with NVP to determine the histologic correlate to the release of DAMPs by hepatocytes. In vivo, debris from necrotic hepatocytes and endothelial cells were present in the liver sinusoids, a condition that can trigger an immune response. In addition to mitochondrial, hepatocytic, and endothelial damage, the drug induced large hepatocytic inclusions composed of lipid droplets surrounded by concentric whorls of smooth endoplasmic reticulum (SER) cisternae-lipid-SER (LSER) inclusions, which were deposited in the sinusoids. NVP is lipid soluble, and these LSER inclusions may be sinks of NVP or its metabolites. LSERs are deposited in the blood stream where they may be picked up by lymph nodes and contribute to initiation of an immune response leading to serious liver injury or skin rash. LSERs migration from liver to the blood stream may signify a novel mechanism of drug exocytosis.


Assuntos
Fármacos Anti-HIV/toxicidade , Retículo Endoplasmático Liso/patologia , Gotículas Lipídicas/patologia , Fígado/efeitos dos fármacos , Nevirapina/toxicidade , Animais , Toxidermias/etiologia , Toxidermias/patologia , Células Endoteliais/patologia , Feminino , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Hepatócitos/ultraestrutura , Corpos de Inclusão/patologia , Fígado/patologia , Fígado/ultraestrutura , Ratos , Ratos Endogâmicos BN
4.
J Assist Reprod Genet ; 35(5): 899-905, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29357025

RESUMO

PURPOSE: In human oocytes, sERCs are one of the dysmorphic phenotypes that have been reported. Significantly reduced pregnancy rates and a comparatively higher number of abnormities in live births appear to be associated with the presence of sERCs in oocytes. However, some reports have shown that healthy babies can be born, without any reduced pregnancy rates, from oocytes observed to contain sERCs. Thus, the clinical and scientific significance of oocytes that harbor sERCs remains controversial. METHODS: The presence of sERCs was evaluated using a time-lapse system while studying the dynamic changes within oocytes and embryos. Logistic regression analysis was carried out to explore the independent variables for meiotic and mitotic cleavage failure.. RESULTS: The incidence of mitotic cleavage failure and the incidence of meiotic cleavage failure during the second polar body extrusion in oocytes with sERCs were found to be significantly higher than that in oocytes without sERCs. Furthermore, ICSI was found to have a greater frequency of meiotic failure than IVF. CONCLUSIONS: In cases of cleavage failure, an embryonic cell could become tetraploid and may induce abnormal chromosomal configurations. Some cells exposed to cleavage failure may become trophectoderm cells and form placental abnormalities. Even if they develop into trophectoderm cells, the ICM can be susceptible to further cleavage failure and may in turn cause further aneuploidy. For these reasons, it is important to monitor pregnancies and births derived from oocytes that contained sERCs.


Assuntos
Retículo Endoplasmático Liso/patologia , Fertilização in vitro/métodos , Oócitos/patologia , Adulto , Feminino , Humanos , Meiose , Injeções de Esperma Intracitoplásmicas/métodos , Imagem com Lapso de Tempo , Resultado do Tratamento
5.
Micron ; 102: 1-14, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28830057

RESUMO

We tested here the ability of bee venom (BV) to interfere with spermatogenesis in rats in two experimental conditions. The histopathological changes were assessed with brightfield microscopy using a novel staining technique, based on methylene blue, orange G and ponceau xylidine. Transmission electron microscopy was also used to identify fine subcellular changes. BV injection for 30days in daily doses of 700µg BV/kg resulted in reducing testicular weight, along with significant larger diameters of seminiferous tubules and reduced number of Sertoli cells (SCs). SCs were vacuolated, detached from the basement membrane, many necrosed, leading to the basement membrane denudation. Germ cells layers were separated by empty spaces conferring a rarefied aspect to the tissue, and spermatids were detached into lumen. Thus, the seminiferous epithelium was significantly thinned. Many Leydig cells (LCs) were in a necrotic state, with disrupted plasma membrane and without smooth endoplasmic reticulum. The acute treatment with a single LD50 of 62mgBV/kg, was followed by focal disruptions of the basement membrane and localized areas of necrosis, mainly affecting the SCs. Most of the observed SCs as well as some spermatogonia were highly vacuoled, empty spaces being observed within the epithelium. The SCs count was significantly decreased. Spermatids had also the tendency of separation from the SCs, and the significant larger diameter of the tubules found was associated with a thicker epithelium. Many LCs were necrosed, with disrupted plasma membrane, swollen mitochondria, no endoplasmic reticulum and implicitly showing rarefied cytoplasm. We concluded that BV was a testicular toxicant affecting both the LCs and the seminiferous tubules. The SCs cells represented the primary target site of BV whose effects were next extended upon the germ cells. In all cells, BV triggered unspecific degenerative changes that could impaire spermatogenesis. The present study also proposes an alternative staining technique very useful in assessing the histopathological aspects of spermatogenesis.


Assuntos
Venenos de Abelha/toxicidade , Epitélio Seminífero/patologia , Epitélio Seminífero/ultraestrutura , Células de Sertoli/ultraestrutura , Espermatogênese/efeitos dos fármacos , Animais , Membrana Basal/patologia , Abelhas/metabolismo , Membrana Celular/patologia , Retículo Endoplasmático Liso/patologia , Células Intersticiais do Testículo/patologia , Masculino , Microscopia Eletrônica de Transmissão , Mitocôndrias/patologia , Necrose/induzido quimicamente , Ratos , Ratos Wistar , Espermátides/ultraestrutura
6.
Fertil Steril ; 106(7): 1718-1724, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27743693

RESUMO

OBJECTIVE: To study whether embryos derived from oocytes presenting a smooth endoplasmic reticulum cluster (SERC) are less likely to develop into blastocysts and implant. DESIGN: Transversal study. SETTING: Private university-affiliated in vitro fertilization (IVF) center. PATIENT(S): Total of 7,609 oocytes obtained from 743 intracytoplasmic sperm injection (ICSI) cycles. INTERVENTION(S): Oocytes split between the SERC-positive cycles (with at least one SERC-positive oocyte) and the SERC-negative cycles (only oocytes free of SERC). MAIN OUTCOME MEASURE(S): Embryo implantation. RESULT(S): A statistically significantly higher mean number of follicles (24.0 ± 10.5 vs. 19.6 ± 10.5), retrieved oocytes (17.8 ± 8.3 vs. 14.3 ± 8.0), and mature oocytes (13.5 ± 6.2 vs. 10.6 ± 5.9) were observed in the SERC-positive cycles as compared with SERC-negative cycles. The implantation rate was statistically significantly lower in SERC-positive cycles as compared with SERC-negative cycles (14.8% vs. 25.6%; odds ratio 0.61; 95% confidence interval, 0.44-0.86). When only cycles with in which none (0) or all the blastocysts transferred had implanted (100%) were analyzed, the mean implantation rate per transferred blastocyst in the SERC-negative group was 20.5%; no blastocysts derived from SERC-positive oocytes implanted. CONCLUSION(S): The occurrence of SERC impairs embryo implantation. Careful oocyte observation that takes into account the presence of SERC should be part of embryo selection strategy before transfer.


Assuntos
Blastocisto/patologia , Implantação do Embrião , Transferência Embrionária , Retículo Endoplasmático Liso/patologia , Infertilidade/terapia , Oócitos/patologia , Injeções de Esperma Intracitoplásmicas/efeitos adversos , Adulto , Feminino , Fertilidade , Humanos , Infertilidade/patologia , Infertilidade/fisiopatologia , Masculino , Pessoa de Meia-Idade , Recuperação de Oócitos , Indução da Ovulação , Gravidez , Taxa de Gravidez , Resultado do Tratamento , Adulto Jovem
7.
Tsitologiia ; 57(2): 129-34, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26035970

RESUMO

A large proportion of human oocytes received from exogenous gonadotropin-stimulated cycles have different morphological attributes, or dysmorphisms. The presence of dysmorphism can affect the fertilization rate, the embryo quality and subsequently the frequency of occurrence of implantation and pregnancy. Special attention is paid to oocytes with cytoplasmic attributes such as alteration of cytoplasmic granularity, the appearance of vacuoles, lipofuscin bodies and visible (large) aggregates of smooth endoplasmic reticulum. Endoplasmic reticulum (ER) is a type of the organelle forming an interconnected network of flattened, membrane-enclosed sacs or tubes. One of the main functions of ER in the oocyte is storage and redistribution of calcium, which provides cell activation during fertilization. Furthermore, complex of ER and mitochondria is necessary for accumulation of energy, synthesis of lipids and triglycerides, as well as synthesis of cytosolic and nuclear membranes during the early stages of cleavage. The appearance of anomalously large aggregates of ER in oocytes correlates with a low fertilization rate, low embryo quality, and pregnancy rate. The aim of the manuscript is to summarize current understanding of the mechanism of formation of such pathology of oocytes, together with special aspects of their fertilization and embryo quality.


Assuntos
Agregação Celular , Retículo Endoplasmático Liso/patologia , Fertilização in vitro , Oócitos/patologia , Citoplasma/metabolismo , Citoplasma/patologia , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/patologia , Retículo Endoplasmático Liso/metabolismo , Feminino , Humanos , Oócitos/metabolismo , Gravidez , Taxa de Gravidez
8.
Toxicol Pathol ; 41(7): 984-91, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23416961

RESUMO

When 100 mg/kg/day of di(n-butyl) phthalate (DBP) was intragastrically administered to pregnant Sprague-Dawley rats throughout gestation days 12 to 21, the male pups had similar body weights with no apparent physical differences (e.g., litter size, sex ratio) compared to that of the vehicle group. However, prominent age-related morphological alterations in the smooth endoplasmic reticulum (sER) of testicular Leydig cells (LCs) were observed once these animals reached puberty. At weeks 5 to 7, the abundant sER with non-dilated cisternae was distributed in LCs. Subsequently, although the number of LCs significantly increased, the amount of sER was significantly decreased at 9 to 14 weeks of age and had disappeared at 17 weeks. In contrast, the number of LCs and the amount of sER in LCs of the lower dose groups (10, 30, and 50 mg/kg/day) were similar to those of the vehicle group. Further, serum testosterone levels in the 100 mg/kg dose group were significantly lower during 5 to 17 weeks of age. While their luteinizing hormone (LH) level was significantly lower at 5 to 7 weeks of age, it became significantly higher during 9 to 17 weeks. The amount of sER in LCs decreased with age with the increase in LCs proliferation and serum LH levels in rat exposed in utero to DBP in a dose-dependent manner.


Assuntos
Dibutilftalato/toxicidade , Retículo Endoplasmático Liso/efeitos dos fármacos , Células Intersticiais do Testículo/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Testosterona/metabolismo , Fatores Etários , Animais , Peso Corporal/efeitos dos fármacos , Dibutilftalato/administração & dosagem , Relação Dose-Resposta a Droga , Retículo Endoplasmático Liso/metabolismo , Retículo Endoplasmático Liso/patologia , Feminino , Células Intersticiais do Testículo/metabolismo , Células Intersticiais do Testículo/patologia , Hormônio Luteinizante/metabolismo , Masculino , Exposição Materna , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/patologia , Ratos , Ratos Sprague-Dawley , Testículo/efeitos dos fármacos , Testículo/metabolismo
9.
Platelets ; 24(1): 44-50, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22757654

RESUMO

The present report describes a fourth patient with platelet pathological features identical to those found in the first three cases with the York platelet syndrome (YPS), as well as other findings that suggest he may be a variant. His platelets contain the same giant opaque and target organelles found earlier, as well as enlarged organelles with a gray appearing matrix. It is possible that the giant structures have the same source, but are at different stages of development. The fourth patient has platelet pathology suggestive of other thrombocyte disorders. He has many large platelets and normal sized thrombocytes nearly devoid of alpha granules. As a result, he was originally thought to have the gray platelet syndrome. He also has significant numbers of platelets attached to platelets and platelets in platelets as seen in patients with the X-linked GATA-1 mutation. Some of the fourth YPS patient's platelets contained massive alpha granules suggesting the possibility of the Paris Trousseau Jacobson Syndrome. Yet, none of these other platelet disorders had giant dense organelles like those found in YPS thrombocytes. As a result, it is reasonable to include this child with the other three, and diagnose him as a patient with the YPS.


Assuntos
Transtornos Plaquetários/patologia , Plaquetas/patologia , Transtornos Plaquetários/terapia , Plaquetas/ultraestrutura , Pré-Escolar , Grânulos Citoplasmáticos/patologia , Grânulos Citoplasmáticos/ultraestrutura , Retículo Endoplasmático Liso/patologia , Retículo Endoplasmático Liso/ultraestrutura , Humanos , Masculino , Megacariócitos/patologia , Megacariócitos/ultraestrutura , Organelas/patologia , Organelas/ultraestrutura , Adesividade Plaquetária , Contagem de Plaquetas
10.
Fertil Steril ; 92(4): 1496.e1-1496.e3, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19646689

RESUMO

OBJECTIVE: To document the relationship between smooth endoplasmic reticulum (SER) aggregations and recurrent fetal anomalies. DESIGN: Case report. SETTING: Private IVF center. PATIENT(S): A 28-year-old woman with an 11-year history of primary infertility. INTERVENTION(S): Three consecutive cycles of intracytoplasmic sperm injection (ICSI) in the same patient. MAIN OUTCOME MEASURE(S): Clinical pregnancy, live birth, fetal anomaly. RESULT(S): In three consecutive ICSI cycles, a total of 59 MII oocytes were retreived in the same patient, all displaying SER aggregations. The fertilization rate per cycle was 80%, 50%, and 42%, respectively. A total of 12 embryos were transferred in three ICSI cycles, of which 11 were grade 1 embryos. Two of the three cycles ended up with clinical ongoing pregnancies but with multiple fetal anomalies. CONCLUSION(S): This is the first case reported with SER aggregations in all retrieved oocytes in three consecutive ICSI cycles. The repetetive multiple fetal anomalies possibly related to oocyte dysmorphism are of concern.


Assuntos
Anormalidades Múltiplas/etiologia , Retículo Endoplasmático Liso/patologia , Oócitos/patologia , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/patologia , Adulto , Feminino , Humanos , Infertilidade/etiologia , Masculino , Recuperação de Oócitos , Oócitos/ultraestrutura , Gravidez , Recidiva , Injeções de Esperma Intracitoplásmicas
11.
Eur Spine J ; 18(4): 473-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19172311

RESUMO

Since the dorsal root ganglia represent the first structure of pain modulation, they are the target of the newest therapies of neuropathic pain. Between these, pulsed radiofrequency (PRF) has been described among the promising non-invasive methods. Although the results encourage the clinical use of this procedure, their mechanism of action is still unclear. Aim of our study was to analyze acute effects of PRF on the rat lumbar ganglion and on nervous fibres running inside it. Clinical works describe PRF treatment as a technique without any visible neurological deficit. The few disposable histological works are contractictory: some describe no signs of cellular damage and some demonstrate visible intracellular modifications. A total of 20 male Wistar rats were deeply anesthesized. Ten were positioned in a stereotactic system, and exposed to PRF at 2 Hz for 30 s after exposition of paravertebral muscles and positioning of a stimulation needle on left L4 ganglion. The other ten were used as controls. After 1 h, the left dorsal root ganglions L3, L4, L5 of the 20 animals were explanted, fixed in 2.5% Karnowsky solution and prepared for light and transmission electron microscopy. At light microscopy no differences between treated and control animals were observed; at transmission electron microscopy, instead, it was possible to observe that T gangliar cells contained an abnormal abundant smooth reticulum with enlarged cisternae and numerous vacuoles; myelinated axons presented pathological features and their myelin coverage was not adherent. Instead, unmyelinated axons appeared normal in shape and dimension and the Schwann cells surrounding it had intact plasmamembrane. Our results, obtained at acute stage, reveal that the PRF procedure should destroy the myelin envelope of nervous fibres. Further future studies, at chronic stage, should give other information on the prognosis of the myelinic damage.


Assuntos
Ablação por Cateter/efeitos adversos , Gânglios Espinais/efeitos da radiação , Degeneração Neural/etiologia , Nociceptores/efeitos da radiação , Doenças do Sistema Nervoso Periférico/terapia , Células Receptoras Sensoriais/efeitos da radiação , Doença Aguda , Animais , Ablação por Cateter/métodos , Modelos Animais de Doenças , Retículo Endoplasmático Liso/patologia , Retículo Endoplasmático Liso/efeitos da radiação , Gânglios Espinais/patologia , Gânglios Espinais/fisiopatologia , Masculino , Microscopia Eletrônica de Transmissão , Degeneração Neural/patologia , Degeneração Neural/fisiopatologia , Fibras Nervosas Mielinizadas/patologia , Fibras Nervosas Mielinizadas/efeitos da radiação , Neuralgia/patologia , Neuralgia/fisiopatologia , Neuralgia/terapia , Nociceptores/patologia , Doenças do Sistema Nervoso Periférico/patologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Ratos , Ratos Wistar , Células Receptoras Sensoriais/patologia , Degeneração Walleriana/etiologia , Degeneração Walleriana/patologia , Degeneração Walleriana/fisiopatologia
12.
Neurosci Lett ; 450(3): 287-91, 2009 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-19047012

RESUMO

Essential tremor (ET) is one of the most common neurological diseases. A basic understanding of its neuropathology is now emerging. Aside from Purkinje cell loss, a prominent finding is an abundance of torpedoes (rounded swellings of Purkinje cell axons). Such swellings often result from the mis-accumulation of cell constituents. Identifying the basic nature of these accumulations is an important step in understanding the underlying disease process. Torpedoes, only recently identified in ET, have not yet been characterized ultrastructurally. Light and electron microscopy were used to characterize the structural constituents of torpedoes in ET. Formalin-fixed cerebellar cortical tissue from four prospectively collected ET brains was sectioned and immunostained with a monoclonal phosphorylated neurofilament antibody (SMI-31, Covance, Emeryville, CA). Using additional sections from three ET brains, torpedoes were assessed using electron microscopy. Immunoreactivity for phosphorylated neurofilament protein revealed clear labeling of torpedoes in each case. Torpedoes were strongly immunoreactive; in many instances, two or more torpedoes were noted in close proximity to one another. On electron microscopy, torpedoes were packed with randomly arranged 10-12nm neurofilaments. Mitochondria and smooth endoplasmic reticulum were abundant as well, particularly at the periphery of the torpedo. We demonstrated that the torpedoes in ET represent the mis-accumulation of disorganized neurofilaments and other organelles. It is not known where in the pathogenic cascade these accumulations occur (i.e., whether these accumulations are the primary event or a secondary/downstream event) and this deserves further study.


Assuntos
Axônios/patologia , Córtex Cerebelar/patologia , Tremor Essencial/patologia , Células de Purkinje/patologia , Idoso de 80 Anos ou mais , Córtex Cerebelar/fisiopatologia , Retículo Endoplasmático Liso/patologia , Tremor Essencial/fisiopatologia , Feminino , Humanos , Microscopia Eletrônica , Microscopia Imunoeletrônica , Mitocôndrias/patologia , Degeneração Neural/patologia , Degeneração Neural/fisiopatologia , Proteínas de Neurofilamentos/metabolismo , Degeneração Walleriana/patologia , Degeneração Walleriana/fisiopatologia
13.
Brain Res ; 1221: 98-107, 2008 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-18559274

RESUMO

Chronic ethanol consumption in aging rats results in regression of Purkinje neuron (PN) dendritic arbors ([Pentney, 1995 Measurements of dendritic pathlengths provide evidence that ethanol-induced lengthening of terminal dendritic segments may result from dendritic regression. Alcohol Alcohol. 30, 87-96]), loss of synapses (Dlugos and Pentney, 1997), dilation of the smooth endoplasmic reticulum (SER), and the formation of degenerating bodies within PN dendrites ([Dlugos, C.A., 2006a. Ethanol-Related Smooth Endoplasmic Reticulum Dilation in Purkinje Dendrites of Aging Rats. Alcohol., Clin. Exp. Res. 30, 883-891,Dlugos, C.A., 2006b. Smooth endoplasmic reticulum dilation and degeneration in Purkinje neuron dendrites of aging ethanol-fed female rats. Cerebellum. 5, 155-162]). Dilation of the SER and the formation of degenerating bodies may be a predictor of dendritic regression. Ethanol-induced effects on mitochondria may be involved as mitochondria cooperate with the SER to maintain calcium homeostasis. The purpose of this study was to determine whether degenerating body number and mitochondrial density and structure are altered by chronic ethanol treatment in PN dendrites. Male, Fischer 344 rats, 12 months of age, were fed an ethanol or pair-fed liquid diet, or rat chow for a period of 10, 20, or 40 weeks (15 rats/treatment; 45 rats/treatment duration). Ethanol-fed rats received 35% of their calories as ethanol. At the end of treatment, all animals were euthanized, perfused, and tissue prepared for electron microscopy. The densities of degenerating bodies and mitochondria, mitochondrial areas, and the distance between the SER and the mitochondria were measured. Results showed that there was an ethanol-related increase in degenerating bodies compared to controls at 40 weeks. Ethanol-induced alterations to mitochondria were absent. Correlation of the present results with those of previous studies suggest that degenerating bodies may be formed from membrane reabsorption during dendritic regression or from degenerating SER whose function has been compromised by dilation.


Assuntos
Envelhecimento/patologia , Transtornos do Sistema Nervoso Induzidos por Álcool/patologia , Dendritos/efeitos dos fármacos , Etanol/toxicidade , Degeneração Neural/induzido quimicamente , Células de Purkinje/efeitos dos fármacos , Transtornos do Sistema Nervoso Induzidos por Álcool/induzido quimicamente , Transtornos do Sistema Nervoso Induzidos por Álcool/fisiopatologia , Animais , Depressores do Sistema Nervoso Central/toxicidade , Córtex Cerebelar/efeitos dos fármacos , Córtex Cerebelar/patologia , Córtex Cerebelar/fisiopatologia , Doenças Cerebelares/induzido quimicamente , Doenças Cerebelares/patologia , Doenças Cerebelares/fisiopatologia , Dendritos/patologia , Modelos Animais de Doenças , Retículo Endoplasmático Liso/efeitos dos fármacos , Retículo Endoplasmático Liso/patologia , Masculino , Microscopia Eletrônica de Transmissão , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Degeneração Neural/patologia , Degeneração Neural/fisiopatologia , Células de Purkinje/patologia , Ratos , Ratos Endogâmicos F344
14.
Ann N Y Acad Sci ; 1086: 66-80, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17185506

RESUMO

A spontaneous neurological mutation, dilute-opisthotonus (dop), was discovered in our breeding colony of Wistar rats. We found that the mutation affected the gene encoding Myosin Va (MyoVA), an actin-based molecular motor. Analysis of the myosin Va (Myo5a) gene of the dop genome showed the presence of a complex rearrangement consisting of a 306-bp inversion associated with 217-bp and 17-bp deletions. A 141-bp exon is skipped in the dop transcript, producing a dop cDNA with a 141 in-frame deletion in the sequences encoding the head region. Expression of the MyoVA protein is severely impaired in the brains of dop homozygous rats, suggesting they have a null mutation for Myo5a. In a morphological analysis of the cerebella of dop rats, we found an absence of smooth endoplasmic reticulum (SER) and of inositol 1,4,5-triphosphate (IP3) receptors in the dendritic spines of Purkinje cells (PC). The SER acts as an intracellular Ca(2+) store and IP3-mediated Ca(2+) signaling in dendritic spines plays a critical role in synaptic regulation. We therefore measured synaptic transmission and long-term depression (LTD), a form of synaptic plasticity underlying cerebellar motor learning, at PC synapses in the cerebella of dop rats. We found that synaptic transmission at the PC synapses is largely normal, whereas the LTD is deficient due to a decrease in IP3-mediated Ca(2+) release from the SER in the PC spines of the dop cerebella. These findings may account for the ataxic movements and clonic convulsions displayed by dop rats. They also contribute to our understanding of the neurological disease mechanisms of the human hereditary disease Griscelli syndrome type 1, which is caused by mutation of the Myo5a gene.


Assuntos
Modelos Animais de Doenças , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Cadeias Pesadas de Miosina/fisiologia , Miosina Tipo V/fisiologia , Doenças do Sistema Nervoso/patologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Encéfalo/metabolismo , Encéfalo/patologia , Dendritos/metabolismo , Dendritos/patologia , Retículo Endoplasmático Liso/metabolismo , Retículo Endoplasmático Liso/patologia , Dados de Sequência Molecular , Mutação , Cadeias Pesadas de Miosina/genética , Miosina Tipo V/genética , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/metabolismo , Células de Purkinje/metabolismo , Células de Purkinje/patologia , Ratos , Ratos Wistar , Transmissão Sináptica , Síndrome
15.
Cerebellum ; 5(2): 155-62, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16818390

RESUMO

The effects of chronic ethanol consumption on the extensive Purkinje neuron (PN) dendritic arbor of male rats include dilation of the smooth endoplasmic reticulum (SER) and dendritic regression. The purpose of the present study was to examine the molecular layer of female rats for the presence of ethanol-related SER dilation and evidence of degeneration within the PN dendritic arbor. Twenty-one 12-month-old Fischer 344 female rats (n = 7/treatment group) received a liquid ethanol, liquid control, or rat chow diet for a period of 40 weeks. Ethanol-fed rats received 35% of their dietary calories as ethanol. Pair-fed rats received a liquid control diet that was isocaloric to the ethanol diet. Chow-fed rats received standard laboratory rat chow ad libitum. At the end of treatment, tissues from the anterior and posterior lobes of the cerebellar vermis were viewed and photographed with the electron microscope. The diameters of SER profiles were measured and the density of degenerating bodies within the PN dendritic arbor was quantitated. In the posterior lobe, ethanol-related SER dilation was apparent. In the anterior lobe, the density of degenerating bodies within PN dendritic shafts was significantly increased but SER dilation in PN dendritic shafts was absent. These results confirm that SER dilation and dendritic degeneration in PN dendrites may precede and contribute to ethanol-related regression in female rats. In addition, comparison of these results with data obtained in male rats from a previous study suggests that PN dendrites in females may be more sensitive to the effects of ethanol.


Assuntos
Transtornos do Sistema Nervoso Induzidos por Álcool/patologia , Transtornos do Sistema Nervoso Induzidos por Álcool/fisiopatologia , Dendritos/efeitos dos fármacos , Retículo Endoplasmático Liso/efeitos dos fármacos , Etanol/toxicidade , Células de Purkinje/efeitos dos fármacos , Envelhecimento/fisiologia , Animais , Depressores do Sistema Nervoso Central/toxicidade , Dendritos/patologia , Dendritos/ultraestrutura , Modelos Animais de Doenças , Retículo Endoplasmático Liso/patologia , Retículo Endoplasmático Liso/ultraestrutura , Feminino , Microscopia Eletrônica de Transmissão , Degeneração Neural/induzido quimicamente , Degeneração Neural/patologia , Degeneração Neural/fisiopatologia , Células de Purkinje/patologia , Células de Purkinje/ultraestrutura , Ratos , Ratos Endogâmicos F344 , Caracteres Sexuais
16.
Alcohol Clin Exp Res ; 30(5): 883-91, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16634858

RESUMO

BACKGROUND: Long-term ethanol consumption in aging rats results in degeneration and regression of the Purkinje neuron (PN) dendritic arbor. One marked ethanol-related change in Purkinje dendrite ultrastructure is dilation of the smooth endoplasmic reticulum (SER) within PN dendritic shafts. The purpose of this study was to determine a time course for ethanol-related dendritic regression in PN dendritic shafts and spines. METHODS: One-hundred eighty aging, male Fischer 344 rats were used. Four durations of treatment (5, 10, 20, and 40 weeks) and 3 dietary treatment groups (60 rats/treatment group) were studied. Ethanol-fed rats received a liquid ethanol diet (35% of dietary calories from ethanol). Pair-fed rats received an isocaloric liquid control diet and chow-fed rats received rat chow and water ad libitum. After each duration of treatment, 45 rats (15/treatment) were euthanized and 2 posterior cerebellar lobules/rat were viewed with electron microscopy and photographed. Diameters of SER profiles within PN shafts and spines were measured with image analysis. RESULTS: Ethanol-related SER dilation in dendritic shafts occurred following 40 weeks of treatment. Ethanol-related SER dilation was not detected in PN dendritic spines. CONCLUSIONS: These results confirm that ethanol-related dilation of SER profiles in PN dendritic shafts occurs following the same duration of treatment as the dendritic regression previously reported in other studies. Degenerating bodies that may be linked to dendritic regression were also identified in PN dendrites.


Assuntos
Envelhecimento , Alcoolismo/patologia , Dendritos/ultraestrutura , Retículo Endoplasmático Liso/patologia , Células de Purkinje/ultraestrutura , Animais , Peso Corporal , Encéfalo/patologia , Dilatação Patológica , Etanol/administração & dosagem , Masculino , Microscopia Eletrônica de Transmissão , Tamanho do Órgão , Ratos , Ratos Endogâmicos F344
17.
Bull Exp Biol Med ; 139(6): 741-6, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16224598

RESUMO

We studied tissue and intracellular reorganization of the liver during total body hypothermia and evaluated regeneration strategies at different levels of structural organization. Hypothermia results in morphofunctional changes in the liver (degeneration, lysis, necrobiosis, and focal necrosis of hepatocytes developing against the background of disorders in blood and lymph circulation). Decreased sinusoid/hepatocyte volume ratio is the key factor in tissue reorganization of the liver. Intracellular reorganization of hepatocytes is characterized by dysproportional changes in the volume and surface densities of the main cytoplasmic organelles involved in biosynthesis and energy production.


Assuntos
Hepatócitos/patologia , Hipotermia Induzida , Fígado/patologia , Animais , Núcleo Celular/patologia , Núcleo Celular/ultraestrutura , Retículo Endoplasmático Rugoso/patologia , Retículo Endoplasmático Rugoso/ultraestrutura , Retículo Endoplasmático Liso/patologia , Retículo Endoplasmático Liso/ultraestrutura , Glicogênio/metabolismo , Glicogênio/ultraestrutura , Hepatócitos/metabolismo , Hepatócitos/ultraestrutura , Fígado/metabolismo , Fígado/ultraestrutura , Lisossomos/patologia , Lisossomos/ultraestrutura , Masculino , Mitocôndrias Hepáticas/patologia , Mitocôndrias Hepáticas/ultraestrutura , Necrose/patologia , Tamanho do Órgão , Ratos , Ratos Wistar , Fatores de Tempo
18.
Virchows Arch ; 444(1): 66-73, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14648220

RESUMO

Mucus overproduction from goblet cells, a characteristic feature of the allergic asthmatic inflammation induced by ovalbumin (OVA) in mice, was examined morphologically. In OVA-untreated (normal) mice, there were no goblet cells in intrapulmonary bronchus and bronchiole. However, goblet cells with or without hyperplasia in the mucosa of inflamed bronchus-bronchiole were recognized in the allergic asthmatic mice. The non-ciliated epithelium containing electron lucent granules (mucus) showed many similarities to Clara cells, which have characteristic secretory granules and many mitochondria, except for the less-developed smooth endoplasmic reticulum seen in normal mice. Ciliated Clara cells with or without mucus were rarely recognized. In addition, mucus was found in neither ciliated nor basal epithelium. The present study suggests that goblet-cell metaplasia in the bronchus and bronchiole of inflamed mucosa may be derived, at least in part, from Clara cells.


Assuntos
Asma/patologia , Células Caliciformes/patologia , Animais , Asma/imunologia , Brônquios/patologia , Modelos Animais de Doenças , Retículo Endoplasmático Liso/patologia , Feminino , Metaplasia , Camundongos , Camundongos Endogâmicos DBA , Microscopia Eletrônica , Mitocôndrias/patologia , Mucosa/patologia , Ovalbumina/imunologia , Vesículas Secretórias/patologia
19.
Brain Res ; 900(1): 152-5, 2001 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-11325359

RESUMO

Reactive astrocytosis in taiep rats was shown by glial fibrillary acidic protein (GFAP) immunoreactivity measured by means of enzyme-linked immunosorbent assay and indirect immunofluorescence. Increased GFAP immunoreactivity was first observed in the brainstem of 15-day-old taiep rats and was widespread throughout all brain regions at 6 months of age. Characteristically, astrocytes were hypertrophic and displayed strong GFAP fluorescence. The pattern of these reactive cells may correlate with the process of dysmyelination in the taiep rat.


Assuntos
Encéfalo/patologia , Doenças Desmielinizantes/genética , Gliose/genética , Animais , Astrócitos/química , Astrócitos/patologia , Ataxia/genética , Biomarcadores , Doenças Desmielinizantes/patologia , Progressão da Doença , Retículo Endoplasmático Liso/patologia , Ensaio de Imunoadsorção Enzimática , Epilepsia Reflexa/genética , Técnica Indireta de Fluorescência para Anticorpo , Proteína Glial Fibrilar Ácida/análise , Gliose/patologia , Hipertrofia , Microtúbulos/patologia , Ratos , Ratos Mutantes , Ratos Sprague-Dawley , Convulsões/genética , Tremor/genética
20.
Alcohol ; 20(2): 125-32, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10719791

RESUMO

The purpose of this study was to determine whether the observed swelling of smooth endoplasmic reticulum (SER) profiles in Purkinje dendrites in our old ethanol-fed F344 rats: (1) represented measurable dilatation, (2) was present in dendritic shafts and spines, and (3) was reversed following recovery from ethanol. Of the 45 rats in 3 treatment groups (chow-fed, pair-fed, and ethanol-fed), 30 rats were euthanized after 40 weeks, and 15 were maintained on rat chow for an additional 20-week recovery period. Electron microscopy of cerebellar preparations was used to analyze morphological alterations in SER profile size within the dendritic shafts and spines of Purkinje neurons. Results showed significant SER dilatation following 40 weeks of ethanol consumption, which disappeared after ethanol withdrawal.


Assuntos
Consumo de Bebidas Alcoólicas/patologia , Retículo Endoplasmático Liso/patologia , Células de Purkinje/patologia , Animais , Depressores do Sistema Nervoso Central/sangue , Dendritos/patologia , Dendritos/ultraestrutura , Dieta , Retículo Endoplasmático Liso/ultraestrutura , Etanol/sangue , Masculino , Células de Purkinje/ultraestrutura , Ratos , Ratos Endogâmicos F344
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