Extraction of phenolic compounds from bean seed coats by acetic acid was evaluated and compared to conventional extraction with 80% methanol. Total phenols, flavonoids and free radical scavenging capacity were determi...Extraction of phenolic compounds from bean seed coats by acetic acid was evaluated and compared to conventional extraction with 80% methanol. Total phenols, flavonoids and free radical scavenging capacity were determined by colorimetric methods. Furthermore, qualitative flavonoid characterization was performed via HPLC diode array. The acetic acid extract contained 73.4 ± 7 mg/g of sample expressed as gallic acid equivalents (GAE), and 41.3 ± 4 mg/g as catechin equivalents (CE). The acetic acid extract (at 1 mg/mL) showed over 89% efficiency to scavenge the 1,1 diphenyl-2-picrylhydrazil (DPPH) radical (EC50 = 6.13 mg extract/mg standard). Gallic acid, delphinidin-3-glycoside, petunidinglycoside, petunidin, malvidin-3-glycoside, myricetin-glycoside, quercitin-glycoside, saponin (β-g), and 3-hydroxy-5, 7-megastigmadien-9-one were identified in both extracts. Additionally, kaempferol-3-glycoside was found in the acetic acid extract. Sequential acetic acid extractions indicated that the antiradical activity was about 90% in DPPH radical scavenging within the first 8 h of extraction, when compared to a 24 h extraction. In general, acetic acid offered a faster and more efficient approach for the extraction of展开更多
The use of stem cells has been proposed as an alternative treatment for certain neurodegenerative disorders. It has also been suggested that in the pre-differentiated state, stem cells might provide a better therapeut...The use of stem cells has been proposed as an alternative treatment for certain neurodegenerative disorders. It has also been suggested that in the pre-differentiated state, stem cells might provide a better therapeutic option than cells that are undifferentiated or fully differentiated. The purpose of this study was to develop a protocol aimed at reducing the incubation time required to induce the conversion of rat mesenchymal stem cells into immature dopaminergic neurons. Stem cells obtained from rat bone marrow were incubated in a control or induction media for 2-24 h. Cells incubated for 24 h in induction medium demonstrated an increase on the levels of the neuronal protein markers nestin, glial fibrillary acid protein, and β-tubulin III, as well as increases in the expression of Pax3, EN1, Thy1.1, and GEF10 genes. This manuscript presents evidence that adult mesenchymal cells are capable to respond, in a short time period, to a neuroinduction medium, and give raise to pre-differentiated neuron like cells representing an alternative for Parkinson disease cell therapy transplantation.展开更多
Cell therapy has been proposed as an alternative treatment for retinal diseases. Applications involving stem cells have shown that undifferentiated cells fail to engraft and cannot convert to retinal cells. However, p...Cell therapy has been proposed as an alternative treatment for retinal diseases. Applications involving stem cells have shown that undifferentiated cells fail to engraft and cannot convert to retinal cells. However, positive results have been reported for retinal precursor cells, suggesting that this approach is the best option. Unfortunately, the source of this cell type is controversial. Predifferentiated adult stem cells may provide an alternative source of cells. The present study proposes a sequential culture media aimed at inducing cells from this source into a preretinal-like lineage. Rat bone marrow stem cells were cultivated in a neuroinduction mix medium for 24 h. The sequence involves immunocytochemistry to detect nestin and tubulin III to demonstrate the cell’s neuronal lineage, followed by incubation in retinal-induction mixed medium for 24 h. RT-PCR was performed to detect expression of Brn3b, Pax6, THY1.1, Opn4, and Ath5 genes. Immunocytochemistry results showed increased expression of nestin and tubulin III after 24 h of incubation in the neuroinduction medium. RT-PCR showed slightly increased expression of Pax6, THY1.1, and Opn4 after 48 h of sequential incubation in the neuroinduction and predifferentiation media. Brn3b and Ath5 gene expression increased markedly. These results suggest that mesenchymal stem cells have a high predisposition to differentiate into preretinal-like cells with minimal time in culture. These cells may provide a viable alternative for restoring damaged retinas.展开更多
Circulating CD133+ stem cells from the peripheral blood have been shown to be able to differentiate into numerous cell lineages. However, adults have only a small number of these circulating stem cells. The aim of the...Circulating CD133+ stem cells from the peripheral blood have been shown to be able to differentiate into numerous cell lineages. However, adults have only a small number of these circulating stem cells. The aim of the present study was to assess a new isolation and enrichment technique for CD133+ stem cells from peripheral blood with the use of Percoll density gradients. Our results demonstrated the presence of two large mononuclear bands when whole blood was centrifuged with 48% and 50% Percoll concentrations. Flow cytometric analysis (FACS) revealed a major CD133+ enrichment at the 48% Percoll concentration in one of the two bands. Further culture of these cells resulted in the formation of multiple colony-forming units. Our results suggest an advantage from using a simple Percoll gradient for successful CD133+ cell recovery, which could aid in differentiation and transplantation protocols.展开更多
文摘Extraction of phenolic compounds from bean seed coats by acetic acid was evaluated and compared to conventional extraction with 80% methanol. Total phenols, flavonoids and free radical scavenging capacity were determined by colorimetric methods. Furthermore, qualitative flavonoid characterization was performed via HPLC diode array. The acetic acid extract contained 73.4 ± 7 mg/g of sample expressed as gallic acid equivalents (GAE), and 41.3 ± 4 mg/g as catechin equivalents (CE). The acetic acid extract (at 1 mg/mL) showed over 89% efficiency to scavenge the 1,1 diphenyl-2-picrylhydrazil (DPPH) radical (EC50 = 6.13 mg extract/mg standard). Gallic acid, delphinidin-3-glycoside, petunidinglycoside, petunidin, malvidin-3-glycoside, myricetin-glycoside, quercitin-glycoside, saponin (β-g), and 3-hydroxy-5, 7-megastigmadien-9-one were identified in both extracts. Additionally, kaempferol-3-glycoside was found in the acetic acid extract. Sequential acetic acid extractions indicated that the antiradical activity was about 90% in DPPH radical scavenging within the first 8 h of extraction, when compared to a 24 h extraction. In general, acetic acid offered a faster and more efficient approach for the extraction of
文摘The use of stem cells has been proposed as an alternative treatment for certain neurodegenerative disorders. It has also been suggested that in the pre-differentiated state, stem cells might provide a better therapeutic option than cells that are undifferentiated or fully differentiated. The purpose of this study was to develop a protocol aimed at reducing the incubation time required to induce the conversion of rat mesenchymal stem cells into immature dopaminergic neurons. Stem cells obtained from rat bone marrow were incubated in a control or induction media for 2-24 h. Cells incubated for 24 h in induction medium demonstrated an increase on the levels of the neuronal protein markers nestin, glial fibrillary acid protein, and β-tubulin III, as well as increases in the expression of Pax3, EN1, Thy1.1, and GEF10 genes. This manuscript presents evidence that adult mesenchymal cells are capable to respond, in a short time period, to a neuroinduction medium, and give raise to pre-differentiated neuron like cells representing an alternative for Parkinson disease cell therapy transplantation.
文摘Cell therapy has been proposed as an alternative treatment for retinal diseases. Applications involving stem cells have shown that undifferentiated cells fail to engraft and cannot convert to retinal cells. However, positive results have been reported for retinal precursor cells, suggesting that this approach is the best option. Unfortunately, the source of this cell type is controversial. Predifferentiated adult stem cells may provide an alternative source of cells. The present study proposes a sequential culture media aimed at inducing cells from this source into a preretinal-like lineage. Rat bone marrow stem cells were cultivated in a neuroinduction mix medium for 24 h. The sequence involves immunocytochemistry to detect nestin and tubulin III to demonstrate the cell’s neuronal lineage, followed by incubation in retinal-induction mixed medium for 24 h. RT-PCR was performed to detect expression of Brn3b, Pax6, THY1.1, Opn4, and Ath5 genes. Immunocytochemistry results showed increased expression of nestin and tubulin III after 24 h of incubation in the neuroinduction medium. RT-PCR showed slightly increased expression of Pax6, THY1.1, and Opn4 after 48 h of sequential incubation in the neuroinduction and predifferentiation media. Brn3b and Ath5 gene expression increased markedly. These results suggest that mesenchymal stem cells have a high predisposition to differentiate into preretinal-like cells with minimal time in culture. These cells may provide a viable alternative for restoring damaged retinas.
文摘Circulating CD133+ stem cells from the peripheral blood have been shown to be able to differentiate into numerous cell lineages. However, adults have only a small number of these circulating stem cells. The aim of the present study was to assess a new isolation and enrichment technique for CD133+ stem cells from peripheral blood with the use of Percoll density gradients. Our results demonstrated the presence of two large mononuclear bands when whole blood was centrifuged with 48% and 50% Percoll concentrations. Flow cytometric analysis (FACS) revealed a major CD133+ enrichment at the 48% Percoll concentration in one of the two bands. Further culture of these cells resulted in the formation of multiple colony-forming units. Our results suggest an advantage from using a simple Percoll gradient for successful CD133+ cell recovery, which could aid in differentiation and transplantation protocols.
