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1.
Acta Biomater ; 54: 249-258, 2017 05.
Article in English | MEDLINE | ID: mdl-28344151

ABSTRACT

Current approaches to derive oligodendrocytes from human pluripotent stem cells (hPSCs) need extended exposure of hPSCs to growth factors and small molecules, which limits their clinical application because of the lengthy culture time required and low generation efficiency of myelinating oligodendrocytes. Compared to extrinsic growth factors and molecules, oligodendrocyte differentiation and maturation can be more effectively modulated by regulation of the cell transcription network. In the developing central nervous system (CNS), two basic helix-loop-helix transcription factors, Olig1 and Olig2, are decisive in oligodendrocyte differentiation and maturation. Olig2 plays a critical role in the specification of oligodendrocytes and Olig1 is crucial in promoting oligodendrocyte maturation. Recently viral vectors have been used to overexpress Olig2 and Olig1 in neural stem/progenitor cells (NSCs) to induce the maturation of oligodendrocytes and enhance the remyelination activity in vivo. Because of the safety issues with viral vectors, including the insertional mutagenesis and potential tumor formation, non-viral transfection methods are preferred for clinical translation. Here we report a poly(ß-amino ester) (PBAE)-based nanoparticle transfection method to deliver Olig1 and Olig2 into human fetal tissue-derived NSCs and demonstrate efficient oligodendrocyte differentiation following transgene expression of Olig1 and Olig2. This approach is potentially translatable for engineering stem cells to treat injured or diseased CNS tissues. STATEMENT OF SIGNIFICANCE: Current protocols to derive oligodendrocytes from human pluripotent stem cells (hPSCs) require lengthy culture time with low generation efficiencies of mature oligodendrocytes. We described a new approach to enhance oligodendrocyte differentiation through nanoparticle-mediated transcription modulation. We tested an effective transfection method using cell-compatible poly (ß-amino ester) (PBAE)/DNA nanoparticles as gene carrier to deliver transcription factor Olig1 and Olig2 into human fetal tissue-derived neural stem/progenitor cells, and showed efficient oligodendrocyte differentiation following transgene expression of Olig1 and Olig2. We believe that this translatable approach can be applied to many other cell-based regenerative therapies as well.


Subject(s)
Cell Differentiation , Nanoparticles/chemistry , Oligodendroglia/metabolism , Pluripotent Stem Cells/metabolism , Transcriptional Activation , Transfection/methods , Basic Helix-Loop-Helix Transcription Factors/biosynthesis , Basic Helix-Loop-Helix Transcription Factors/genetics , Cell Differentiation/drug effects , Cell Differentiation/genetics , Humans , Nerve Tissue Proteins/biosynthesis , Nerve Tissue Proteins/genetics , Oligodendrocyte Transcription Factor 2/biosynthesis , Oligodendrocyte Transcription Factor 2/genetics , Oligodendroglia/cytology , Pluripotent Stem Cells/cytology , Transcriptional Activation/drug effects , Transcriptional Activation/genetics
2.
Biomater Sci ; 4(7): 1100-12, 2016 Jun 21.
Article in English | MEDLINE | ID: mdl-27328202

ABSTRACT

Central nervous system (CNS) diseases and injuries are accompanied by reactive gliosis and scarring involving the activation and proliferation of astrocytes to form hypertrophic and dense structures, which present a significant barrier to neural regeneration. Engineering astrocytes to functional neurons or oligodendrocytes may constitute a novel therapeutic strategy for CNS diseases and injuries. Such direct cellular programming has been successfully demonstrated using viral vectors via the transduction of transcriptional factors, such as Sox2, which could program resident astrocytes into neurons in the adult brain and spinal cord, albeit the efficiency was low. Here we report a non-viral nanoparticle-based transfection method to deliver Sox2 or Olig2 into primary human astrocytes and demonstrate the effective conversion of the astrocytes into neurons and oligodendrocyte progenitors following the transgene expression of Sox2 and Olig2, respectively. This approach is highly translatable for engineering astrocytes to repair injured CNS tissues.


Subject(s)
Astrocytes/cytology , Cell Differentiation , Nanoparticles/administration & dosage , Neurons/cytology , Oligodendroglia/cytology , Transfection/methods , Cell Engineering , Humans , Nanoparticles/chemistry , Oligodendrocyte Transcription Factor 2/administration & dosage , SOXB1 Transcription Factors/administration & dosage , Spinal Cord Injuries/therapy
3.
J. bras. patol. med. lab ; 49(2): 126-129, Apr. 2013. ilus
Article in English | LILACS | ID: lil-678241

ABSTRACT

Strumal carcinoid tumor is an uncommon type of ovarian teratoma containing thyroid and carcinoid tissue. We report the case of a 49 year-old patient with menstrual irregularity. The ultrasonographic imaging revealed a mass in the left ovary. The histopathological assessment showed a papillary thyroid carcinoma in a strumal carcinoid tumor.


Carcinoide strumal é uma forma incomum de teratoma ovariano que contém tecido tireoidiano e carcinoide. Relatamos o caso de uma paciente de 49 anos de idade, cuja investigação por irregularidade menstrual revelou massa em ovário esquerdo à ultrassonografia. A avaliação histopatológica da massa apresentou carcinoma papilífero de tecido tireoideano em carcinoide strumal.


Subject(s)
Humans , Female , Middle Aged , Carcinoma, Papillary , Diagnostic Imaging , Carcinoid Tumor
4.
Acta Cir Bras ; 27(7): 460-4, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22760830

ABSTRACT

PURPOSE: To determine the impact of hypertension in liver regeneration, in rats by examining gain in liver mass and the replication of hepatocytes and stellate cells. METHODS: Forty Wistar rats were allocated into two groups of twenty, the control and experiment group. The experiment group animals were submitted to induction of renovascular hypertension. A week later, all the animals underwent a partial hepatectomy. Measurements were taken after 24 hours and seven days, when ten animals in each group were euthanized. Thus, four subgroups were obtained. The livers were excised and sent for histopathological analysis. RESULTS: The control group had a greater gain in liver mass than the experiment group seven days after partial hepatectomy (p=0.0051). The difference in the activate stellate cell count was not statistically significant following analysis after both 24 hours and seven days (p=1.0). A higher number of dividing hepatocytes was observed in the control group seven days after partial hepatectomy (p=0.0014). CONCLUSION: In rats, hypertension had no direct influence on stellate cell replication, but led to a delay in liver mass gain and were shown to be a reduction factor on hepatocyte replication seven days after partial hepatectomy.


Subject(s)
Hepatic Stellate Cells/physiology , Hepatocytes/physiology , Hypertension/physiopathology , Liver Regeneration/physiology , Liver/physiology , Animals , Cell Count , Hepatectomy , Liver/cytology , Male , Organ Size , Random Allocation , Rats , Rats, Wistar , Time Factors
5.
Acta cir. bras ; 27(7): 460-464, jul. 2012. graf, tab
Article in English | LILACS | ID: lil-640093

ABSTRACT

PURPOSE: To determine the impact of hypertension in liver regeneration, in rats by examining gain in liver mass and the replication of hepatocytes and stellate cells. METHODS: Forty Wistar rats were allocated into two groups of twenty, the control and experiment group. The experiment group animals were submitted to induction of renovascular hypertension. A week later, all the animals underwent a partial hepatectomy. Measurements were taken after 24 hours and seven days, when ten animals in each group were euthanized. Thus, four subgroups were obtained. The livers were excised and sent for histopathological analysis. RESULTS: The control group had a greater gain in liver mass than the experiment group seven days after partial hepatectomy (p=0.0051). The difference in the activate stellate cell count was not statistically significant following analysis after both 24 hours and seven days (p=1.0). A higher number of dividing hepatocytes was observed in the control group seven days after partial hepatectomy (p=0.0014). CONCLUSION: In rats, hypertension had no direct influence on stellate cell replication, but led to a delay in liver mass gain and were shown to be a reduction factor on hepatocyte replication seven7 days after partial hepatectomy.


OBJETIVO: Determinar o impacto da hipertensão arterial sistêmica na regeneração hepática, em ratos, através da análise do ganho de massa hepática e da replicação dos hepatócitos e das células estreladas. MÉTODOS: Alocaram-se 40 ratos Wistar em dois grupos de 20 animais, os grupos controle e experimento. Os do grupo experimento submeteram-se a indução da hipertensão renovascular. Uma semana após, realizou-se hepatectomia parcial em todos os animais. Colheram-se os dados com 24 horas e sete dias, quando dez animais de cada grupo submeteram-se a eutanásia. Assim, obtiveram-se quatro subgrupos. Os fígados foram retirados e enviados para análise histopatológica. RESULTADOS: O grupo controle apresentou maior ganho de massa hepática do que o grupo experimento sete dias após a hepatectomia parcial (p=0,0051). A diferença na contagem das células estreladas ativadas não foi estatisticamente significante nas análises de 24 horas e de sete dias (p=1,0). Um maior número de hepatócitos em divisão foi observado no grupo controle, sete dias após a hepatectomia parcial (p=0,0014). CONCLUSÃO: Em ratos, a hipertensão não teve influência direta sobre a replicação de células estreladas, mas levou ao atraso no ganho de massa hepática e mostrou ser um fator de redução na replicação de hepatócitos sete dias após a hepatectomia parcial.


Subject(s)
Animals , Male , Rats , Hepatic Stellate Cells/physiology , Hepatocytes/physiology , Hypertension/physiopathology , Liver Regeneration/physiology , Liver/physiology , Cell Count , Hepatectomy , Liver/cytology , Organ Size , Random Allocation , Rats, Wistar , Time Factors
6.
Pharmacol Biochem Behav ; 102(2): 233-40, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22579911

ABSTRACT

Baclofen, a GABA(B) agonist, reduces ethanol intake in animals and humans, but the contrary or no effect was also reported. Our previous study demonstrated that mice characterized as "loss of control over ethanol intake" had different Gabbr1 and Gabbr2 transcription levels, which express, respectively, the GABA(B1) and GABA(B2) subunits in brain areas related to addictive behavior. In the present study, we tested baclofen on ethanol intake in mice exposed to the free-choice paradigm. Adult male Swiss mice, individually housed, had free access to three bottles: ethanol (5% and 10%) and water. The protocol had four phases: acquisition (AC, 10 weeks), withdrawal (W, 4 cycles during 2 weeks of 2 day-free-choice and 2 day-only-water), reexposure (RE, 2 weeks), and adulteration of ethanol solutions with quinine (AD, 2 weeks). Mice characterized as "loss of control" (A, n=11, preference for ethanol in AC and maintenance of ethanol intake levels in AD), heavy (H, n=11, preference for ethanol in AC and reduction of ethanol intake levels in AD), and light (L, n=16, preference for water in all phases) drinkers were randomly distributed into two subgroups receiving either intraperitoneal injections of all doses of baclofen (1.25, 2.5, and 5.0mg/kg, given each dose twice in consecutive days) or saline, being exposed to free-choice. Fluid consumption was measured 24h later. Baclofen reduced ethanol intake in group L. In group H a reduction compared to AC was observed. Group A maintained their high ethanol intake even after baclofen treatment. Activation of the GABA(B) receptor depends on the precise balance between the GABA(B1) and GABA(B2) subunits, so the disproportionate transcription levels, we reported in group A, could explain this lack of response to baclofen. These data highlight the importance to test baclofen in individuals with different ethanol drinking profiles, including humans.


Subject(s)
Alcohol Drinking , Baclofen/pharmacology , Ethanol/administration & dosage , GABA Agonists/pharmacology , Receptors, GABA-B/drug effects , Animals , Body Weight , Dose-Response Relationship, Drug , Drinking Behavior , Male , Mice
7.
Rev. cir. traumatol. buco-maxilo-fac ; 12(1): 43-46, Jan.-Mar. 2012. ilus
Article in Portuguese | LILACS | ID: lil-792124

ABSTRACT

O Carcinoma mucoepidermoide juvenil é uma doença rara, que ocorre mais frequentemente nas glândulas menores do palato duro. Os pacientes, em geral, referem edema progressivo e indolor. O tratamento de escolha é a ressecção cirúrgica, estando a radioterapia indicada no pós-operatório, em casos de presença de fatores de mau prognóstico. Relatamos o caso de uma paciente de 12 anos de idade com carcinoma mucoepidermoide juvenil em palato duro com radioterapia adjuvante.


Juvenile mucoepidermoid carcinoma is a rare disease that occurs most often in the minor glands of the hard palate. Patients usually report a progressive, painless swelling. The treatment of choice is surgical resection, with radiotherapy given postoperatively when poor prognostic factors are present. We report the case of a 12-year-old female with mucoepidermoid carcinoma of the hard palate with adjuvant radiotherapy.

8.
Rev. bras. mastologia ; 21(2): 81-85, abr.-jun. 2011. ilus
Article in Portuguese | LILACS | ID: lil-699579

ABSTRACT

O carcinoma apócrino de mama é raro e, por esse motivo, permanece com origem e definição controversas. Há quem acredite que se trate de uma variante do carcinoma invasivo. Apresenta-se em cerca de 0,5 a 8% dos casos de carcinoma mamário, não sendo possível sua diferenciação em relação aos carcinomas usuais da mama por meio de exames radiológicos. O diagnóstico pode ser realizado pela citologia, que é típica desse tumor. Geralmente é positivo para a GCDFP-15(gross cystic disease fluid protein-15), marcador de diferenciação apócrina mais confiável do que amorfologia. A imunoistoquímica costuma ser negativa para estrógeno e progesterona e positiva para o receptor de andrógeno. A taxa de positividade para a p53, HER-2 e BCL-2 em carcinomas apócrinos é quase a mesma que para os carcinomas não apócrinos. O tratamento é cirúrgico; a adjuvância costuma ser a mesma do carcinoma ductal invasor e, ao que tudo indica, também tem o mesmo prognóstico.


Apocrine carcinoma of the breast is a rare condition, and for this reason its origin and definition remains controversial. Some believe that is a variant of invasive carcinoma. The incidence of this disease is about 0.5 to 8% of the new diagnosed cases of breast carcinoma. Since it is not possible to differentiate the apocrine carcinoma from the usual breast carcinomas by using radiological images, diagnosis can be made by cytology showing typical alterations of this tumor. It is usually positive for GCDFP-15 (gross cystic disease fluid protein-15), a marker of apocrine differentiation more reliable than morphology. This type of tumor is often negative for estrogen and progesterone and positive for the androgen receptor. The rate of positivity for p53, HER-2 and BCL-2 in apocrine carcinomas is almost the same as for non-apocrine carcinomas. The surgical and adjuvant treatment is normally the same as invasive ductal carcinoma, and both seem also to have the same prognosis.


Subject(s)
Humans , Female , Aged , Adenocarcinoma/surgery , Adenocarcinoma/diagnosis , Apocrine Glands/pathology , Breast Neoplasms/surgery , Breast Neoplasms/diagnosis , Combined Modality Therapy
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