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Hyaline cartilage is a highly specialized tissue. When injured, its repair capacity is low, which results in the massive destruction of the articular surface. Using tissue engineering and genetic engineering techniques, it is possible to provide a suitable microenvironment providing chondrocyte growth factors involved in the development of hyaline cartilage proteins, as well as cell proliferation and differentiation. Our aim was to stimulate the synthesis of an extracellular matrix via the chondrocytes included in a fibrin matrix through the addition or overexpression of IGF1 and/or FGF2, while maintaining a constant agitation of the culture medium. Collagen type II and glycosaminoglycans increased during the entire incubation time. In contrast, collagen type I decreased its expression under the same culture conditions, transfecting or supplementing growth factors to chondrocytes. However, chondrocytes that were not transfected or supplemented showed a general increase in the proteins analyzed in this study. The presence of IGF1 and FGF2 increased the protein synthesis of the hyaline cartilage, regardless of which one was the source of growth factors. Continuous agitation using the spinner flask allows for the adequate nutrition of chondrocytes included in the fibrin matrix. However, they require growth factors to up-regulate or down-regulate collagenous proteins.
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BACKGROUND: Cancer treatment has many side effects; therefore, more efficient treatments are needed. Mesenchymal stem cells (MSC) have immunoregulatory properties, tumor site migration and can be genetically modified. Some proteins, such as soluble TRAIL (sTRAIL) and interleukin-12 (IL-12), have shown antitumoral potential, thus its combination in solid tumors could increase their activity. MATERIALS AND METHODS: Lentiviral transduction of bone marrow MSC with green fluorescent protein (GFP) and transgenes (sTRAIL and IL-12) was confirmed by fluorescence microscopy and Western blot. Soluble TRAIL levels were quantified by ELISA. Lymphoma L5178Y cells express a reporter gene (GFP/mCherry), and TRAIL receptor (DR5). RESULTS: An in vivo model showed that combined treatment with MSC expressing sTRAIL+IL-12 or IL-12 alone significantly reduced tumor volume and increased survival in BALB/c mice (p < 0.05) with only one application. However, at the histological level, only MSC expressing IL-12 reduced tumor cell infiltration significantly in the right gastrocnemius compared with the control group (p < 0.05). It presented less tissue dysplasia confirmed by fluorescence and hematoxylin-eosin dye; nevertheless, treatment not inhibited hepatic metastasis. CONCLUSIONS: MSC expressing IL-12, is or combination with BM-MSC expressing sTRAIL represents an antitumor strategy for lymphoma tumors since they increase survival and reduce tumor development. However, the combination did not show significative additive effect. The localized application did not inhibit metastasis but reduced morphological alterations of tissue associated with liver metastasis.
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INTRODUCTION: The iatrogenic effects of repairing peripheral nerve injuries (PNIs) with autografts (AGTs) encouraged the present study to involve a new approach consisting of grafting xenogeneic prerecellularized allogeneic cells instead of AGTs. METHODS: We compared sheep's AGT regenerative and functional capacity with decellularized human nerves prerecellularized with allogeneic Schwann-like cell xenografts (onwards called xenografts). Mesenchymal stem cells were isolated from ovine adipose tissue and induced in vitro to differentiate into Schwann-like cells (SLCs). Xenografts were grafted in ovine sciatic nerves. Left sciatic nerves (20 mm) were excised from 10 sheep. Then, five sheep were grafted with 20 mm xenografts, and five were reimplanted with their nerve segment rotated 180° (AGT). RESULTS: All sheep treated with xenografts or AGT progressively recovered the strength, movement, and coordination of their intervened limb, which was still partial when the study was finished at sixth month postsurgery. At this time, numerous intrafascicular axons were observed in the distal and proximal graft extremes of both xenografts or AGTs, and submaximal nerve electrical conduction was observed. The xenografts and AGT-affected muscles appeared partially stunted. CONCLUSIONS: Xenografts and AGT were equally efficacious in starting PNI repair and justified further studies using longer observation times. The hallmarks from this study are that human xenogeneic acellular scaffolds were recellularized with allogenic SCL and were not rejected by the nonhuman receptors but were also as functional as AGT within a relatively short time postsurgery. Thus, this innovative approach promises to be more practical and accessible than AGT or allogenic allografts and safer than AGT for PNI repair.
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Colorectal cancer (CRC) is one of the main causes of mortality. Recent studies suggest that cancer stem cells (CSCs) can survive after chemotherapy and promote tumor invasiveness and aggression. According to a higher hierarchy complexity of CSC, different protocols for isolation, expansion, and characterization have been used; however, there are no available resistance biomarkers that allow predicting the clinical response of treatment 5fluorouracil (5FU) and oxaliplatin. Therefore, the primary aim of the present study was to analyze the expression of gene resistance on tumors and CSCderived isolates from patients CRC. In the present study, adenocarcinomas of the colon and rectum (CRAC) were classified based on an in vitro adenosine triphosphatebased chemotherapy response assay, as sensitive and resistant and the percentage of CD24 and CD44 markers are evaluated by immunohistochemistry. To isolate resistant colonCSC, adenocarcinoma tissues resistant to 5FU and oxaliplatin were evaluated. Finally, all samples were sequenced using a custom assay with chemoresistanceassociated genes to find a candidate gene on resistance colonCSC. Results showed that 59% of the CRC tissue analyzed was resistant and had a higher percentage of CD44 and CD24 markers. An association was found in the expression of some genes between the tumorresistant tissue and CSC. Overall, isolates of the CSC population CD44+ resistant to 5FU and oxaliplatin demonstrated different expression profiles; however, the present study was able to identify overexpression of the KRT18 gene, in most of the isolates. In conclusion, the results of the present study showed overexpression of KRT18 in CD44+ cells is associated with chemoresistance to 5FU and oxaliplatin in CRAC.
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Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Células-Tronco Neoplásicas , Adenocarcinoma/patologia , Adulto , Idoso , Biomarcadores Tumorais/genética , Antígeno CD24 , Feminino , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica , Humanos , Receptores de Hialuronatos , Imuno-Histoquímica/métodos , Masculino , Pessoa de Meia-Idade , Oxaliplatina/farmacologiaRESUMO
Some medical applications of magnetic nanoparticles require direct contact with healthy tissues and blood. If nanoparticles are not designed properly, they can cause several problems, such as cytotoxicity or hemolysis. A strategy for improvement the biological proprieties of magnetic nanoparticles is their functionalization with biocompatible polymers and nonionic surfactants. In this study we compared bare magnetite nanoparticles against magnetite nanoparticles coated with a combination of polyethylene glycol 3350 (PEG 3350) and polysorbate 80 (Tween 80). Physical characteristics of nanoparticles were evaluated. A primary culture of sheep adipose mesenchymal stem cells was developed to measure nanoparticle cytotoxicity. A sample of erythrocytes from a healthy donor was used for the hemolysis assay. Results showed the successful obtention of magnetite nanoparticles coated with PEG 3350-Tween 80, with a spherical shape, average size of 119.2 nm and a zeta potential of +5.61 mV. Interaction with mesenchymal stem cells showed a non-cytotoxic propriety at doses lower than 1000 µg/mL. Interaction with erythrocytes showed a non-hemolytic propriety at doses lower than 100 µg/mL. In vitro information obtained from this work concludes that the use of magnetite nanoparticles coated with PEG 3350-Tween 80 is safe for a biological system at low doses.
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PURPOSE: To determine in vitro, the efficacy and safety window of not-front-line and first-line anti-colorectal (CRC) drug combinations. METHODS: The adenocarcinoma cell line Colo 320DM and normal human mesenchymal stem cells derived from adipose tissue were used respectively to determine the anti-CRC efficacy (% of Colo 320DM cell death [CD]) and safety window [SW] - % Colo 320DM percent cancer death (PCD)/% of mesenchymal stem cell's death) of drug combinations, using the adenosine triphosphate-based chemotherapy response assay (ATP-CRA). RESULTS: First-line anti-CRC drug combinations (5-fluorouracil [5FU]/oxaliplatin [oxa] and 5-FU/Oxa /leucovorin [Leuco]) produced 57.7% and 52.4% CD, and 1.38 and 2.44 SW, respectively. Combinations of 5-FU/Oxa and 1 to 3 non-front line drugs led to 56.3-99.8% CD and to 0.96-2.2 SW. The highest safety window corresponded to 5FU/Oxa/ carboplatin [Carbo] (93% CD and 1.4 SW) and to 5-FU/ Oxa/cisplatin [Cispl] (93.5% CD and 1.4 SW). In contrast, non-front line drugs led to 89.8-97.4% CD and to 1.1-78.2 SW. Outstandingly, those combinations containing Carbo/ Cispl/3,3'-diindolylmethane (DIM), aspirin (Asp), or 3,3'- DIM/ Asp showed a very high CD (91.9-96.9% [39.2-39.5 times higher than first-line-combined drugs]) and very wide SW (57.8-81.56 [66.6-40 times higher than the first-line drug combinations]). CONCLUSIONS: Human mesenchymal stem cells could be an excellent alternative to laboratory animals, when testing the safety profiles of drugs. The most promising combinations of non-frontline drugs to treat CRC are Carbo/Cispl/ Asp and Carbo/Cispl/DIM.
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Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Compostos Organoplatínicos/uso terapêutico , Adenocarcinoma/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Linhagem Celular , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Compostos Organoplatínicos/farmacologiaRESUMO
Adipose-derived mesenchymal stem cells (ADMSCs) are inducible to an osteogenic phenotype by the bone morphogenetic proteins (BMPs). This facilitates the generation of implants for bone tissue regeneration. This study evaluated the in vitro osteogenic differentiation of ADMSCs transduced individually and in combination with adenoviral vectors expressing BMP2 and BMP7. Moreover, the effectiveness of the implant containing ADMSCs transduced with the adenoviral vectors AdBMP2/AdBMP7 and embedded in demineralized bone matrix (DBM) was tested in a model of tibial fracture in sheep. This graft was compared to ewes implanted with untransduced ADMSCs embedded in the same matrix and with injured but untreated animals. In vivo results showed accelerated osteogenesis in the group treated with the AdBMP2/AdBMP7 transduced ADMSC graft, which also showed improved restoration of the normal bone morphology.
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BACKGROUND: Pyogenic granuloma is a non-neoplastic lesion that frequently occurs in the skin and mucous membranes of children and pregnant women. The anatomical sites of pyogenic granulomas overlap with those of wart infections caused by the human papillomavirus (HPV). OBJECTIVE: This study assessed the presence of HPV DNA in pyogenic granuloma samples by polymerase chain reaction. METHODS: Eighteen pyogenic granuloma biopsies from patients without a clinical history or evidence of verruca in the studied area were tested for the presence of the HPV genome. The presence of HPV DNA was screened by three independent polymerase chain reaction reactions using standard consensus primer sets targeted to the L1 or E1 consensus regions of HPV genome. The HPV DNA-positive samples were genotyped using methodologies enabling the identification of up to 30 HPVs, including oncogenic, nononcogenic, and cutaneous viral types. RESULTS: The HPV DNA was detected in 44.4% (eight of 18) of the samples, with HPV-2 being the only type in the eight HPV DNA-positive samples. Contamination with HPV-2 sequences throughout the entire process was reliably eliminated. CONCLUSION: This report is the first to suggest an association between HPV-2 and pyogenic granuloma. This relationship is similar to that observed between HPV-2 and nongenital warts.
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DNA Viral/análise , Granuloma Piogênico/virologia , Papillomaviridae/isolamento & purificação , Adolescente , Adulto , Braço , Criança , Feminino , Genótipo , Cabeça , Humanos , Masculino , Pessoa de Meia-Idade , Pescoço , Reação em Cadeia da Polimerase , Tórax , Adulto JovemRESUMO
An area of research that has been recently gaining attention is the relationship between cancer stem cell (CSC) biology and chemo-resistance in colon cancer patients. It is well recognized that tumor initiation, growth, invasion and metastasis are promoted by CSCs. An important reason for the widespread interest in the CSC model is that it can comprehensibly explain essential and poorly understood clinical events, such as therapy resistance, minimal residual disease, and tumor recurrence. This review discusses the recent advances in colon cancer stem cell research, the genes responsible for CSC chemoresistance, and new therapies against CSCs.
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UNLABELLED: Environmental and genetic factors may modify or contribute to the phenotypic differences observed in multigenic and monogenic diseases, such as cystic fibrosis (CF). An analysis of modifier genes can be helpful for estimating patient prognosis and directing preventive care. The aim of this study is to determine the association between seven genetic variants of four modifier genes and CF by comparing their corresponding allelic and genotypic frequencies in CF patients (nâ=â81) and control subjects (nâ=â104). Genetic variants of MBL2 exon 1 (A, B, C and D), the IL-8 promoter (-251 A/T), the TNFα promoter (TNF1/TNF2), and SERPINA1 (PI*Z and PI*S) were tested in CF patients and control subjects from northeastern Mexico by PCR-RFLP. RESULTS: The TNF2 allele (Pâ=â0.012, OR 3.43, 95% CI 1.25-9.38) was significantly associated with CF under the dominant and additive models but was not associated with CF under the recessive model. This association remained statistically significant after adjusting for multiple tests using the Bonferroni correction (Pâ=â0.0482). The other tested variants and genotypes did not show any association with the disease. CONCLUSION: An analysis of seven genetic variants of four modifier genes showed that one variant, the TNF2 allele, appears to be significantly associated with CF in Mexican patients.
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Fibrose Cística/genética , Genes Modificadores , Polimorfismo Genético , Regiões Promotoras Genéticas , Fator de Necrose Tumoral alfa/genética , Alelos , Estudos de Casos e Controles , Fibrose Cística/patologia , Feminino , Frequência do Gene , Genótipo , Humanos , Interleucina-8/genética , Masculino , Lectina de Ligação a Manose/genética , México , Modelos Genéticos , alfa 1-Antitripsina/genéticaRESUMO
BACKGROUND: Bone morphogenetic proteins (BMPs) are actively involved in ossification, and BMP-2 participates throughout the entire process. Gene therapy for bone regeneration using adenovirus-expressing BMPs has been successful in small mammals, but it has not been satisfactory in large mammals. METHODS: We generated a 3-component implant (3C graft) comprising autologous mesenchymal stem cells (MSCs), ex vivo transduced with an adenovirus vector-expressing BMP-2 and embedded in a demineralized human bone matrix (DBM). RESULTS: In vitro studies demonstrated vector-induced osteogenesis; osteoblast population and mineralization of the extracellular matrix were greater in the vector-transduced cultures than in the controls (nontransduced MSCs stimulated with osteogenic media were used as positive controls, and nontransduced MSCs served as a negative control). The 3-component grafts were used to fill osteotomies created by bone distraction surgery in mongrel dogs. Control groups comprised dogs with bone distraction alone and dogs with nontransduced MSC grafts. The radiography follow-up, performed 10 weeks after distraction, demonstrated a remarkable reduction in the consolidation period compared with controls. Postmortem mandibles submitted for anatomic and histologic analyses showed improved remodeling and bone maturation in the 3C-grafted dogs. Inflammatory infiltrates were not observed in any of the treated areas, and no liver toxicity was detected. CONCLUSIONS: We demonstrated acceleration of osteogenesis in a dog model for bone distraction by using an implant of BMP-2 modified MSCs. These results are helpful for future clinical trials of mandible bone distraction.
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Proteína Morfogenética Óssea 2/farmacologia , Regeneração Óssea/efeitos dos fármacos , Regeneração Óssea/genética , Mandíbula/cirurgia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese por Distração/métodos , Adenoviridae/genética , Animais , Western Blotting , Estudos de Casos e Controles , Técnicas de Cultura de Células , Cães , Citometria de Fluxo , Vetores Genéticos/genética , Humanos , Técnicas Imunoenzimáticas , Modelos Animais , Osteoblastos/efeitos dos fármacos , Osteotomia , Transdução GenéticaRESUMO
To investigate the ancestral admixture in the Mestizo population in northeastern Mexico, we genotyped 74 ancestral informative markers (AIMs) and 15 Y-single-nucleotide polymorphisms (Y-SNPs) in 100 individuals. The Native American contribution is 56% (range: 27.4-81.2%), the European contribution is 38% (range: 16.7-70.5%) and the West African contribution is 6%. The results show a higher European contribution than was reported in other similar studies in the country, albeit with a predominant Native American ancestry. No remarkable differences in the ancestry proportions were observed using subgroups of 74, 54, 34 and 24 AIMs. The paternal lineage calculated by genotyping of 15 Y-SNPs, shows a major component of European and Eurasian ancestry markers ( approximately 78%), compared with Amerindian ( approximately 12%) and African markers (10%). This information will set a reference for future determinations of admixture proportions in the Mestizo population from Mexico and for population-based association studies of complex diseases.
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População Negra/genética , Cromossomos Humanos Y/genética , DNA/genética , Genética Populacional , Indígenas Norte-Americanos/genética , Polimorfismo de Nucleotídeo Único/genética , População Branca/genética , Humanos , Masculino , México , FilogeniaRESUMO
Recent information has extended leptin's action, beyond the control of appetite, to various sites of metabolic regulation. To better understand leptin's role we studied its production in subcutaneous and visceral fat compartments before and after menopause. During elective abdominal surgery, biopsies of subcutaneous and omental tissues were taken from 20 women at pre- (BMI 28.4 +/- 4.5 kg/m2) and 10 at postmenopause (BMI 30.6 +/- 7.7 kg/m2). In both groups serum leptin levels were similar, and highly correlated with BMI. In subcutaneous adipose tissue, leptin mRNA expression was significantly higher in pre- than in postmenopausal women (50.4 +/- 20.5 amol/microg total RNA versus 34.5 +/- 24.9 amol/microg total RNA, respectively). Leptin mRNA expression in subcutaneous tissue was independently correlated with fasting glucose (R = 0.89, P < 0.006) at premenopause, and with serum estradiol (R = 0.77, P < 0.04) at postmenopause. Leptin mRNA expression in visceral fat was correlated with DHEAS (R = 0.86, P < 0.001), at premenopause. These results indicate that in both compartments, leptin production is sensitive to different but overlapping stimuli, conveying information about energy availability to central and peripheral sites under different conditions of estrogen exposure.
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Hormônios/sangue , Leptina/genética , Pós-Menopausa/metabolismo , Pré-Menopausa/metabolismo , RNA Mensageiro/metabolismo , Tecido Adiposo/metabolismo , Adulto , Idoso , Índice de Massa Corporal , Estradiol/sangue , Feminino , Glucose/metabolismo , Humanos , Leptina/sangue , Pessoa de Meia-Idade , Pós-Menopausa/sangue , Pós-Menopausa/genética , Pré-Menopausa/sangue , Pré-Menopausa/genética , RNA Mensageiro/genéticaRESUMO
The adoption of a bacterial system of control of genic expression with tetracycline, combined with the advances in the identification of regulatory sequences and mechanisms of expression of eukaryotic genes, has increased the versatility and effectiveness of techniques to reintroduce and to make genes function in cells and in superior organisms by being able to control the activity of the transgene in a temporary or reversible manner. This approach has also facilitated making detailed studies of different cellular processes and diseases; for example, the study of the function of oncogenes and other genes involved in the formation and progression of cancer, the generation of cellular models for recombinant protein production with therapeutic purposes, the ex-vivo genetic manipulation of extracted cells from patients and returned to them for gene therapy procedures, as well as the modulation of transgenes to revert hereditary suffering in animal models.
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Biossíntese de Proteínas/efeitos dos fármacos , Proteínas Recombinantes/biossíntese , Tetraciclina/farmacocinética , Transgenes/efeitos dos fármacos , Animais , Humanos , Organismos Geneticamente ModificadosRESUMO
Trichomonad total extracts (TTE), or vesicular (P30) and soluble (530) subcellular fractions from 3 pathogenic Trichomonas vaginalis strains (GT-3. GT-13. and GT-15), lysed both human and Sprague-Dawley rat erythrocytes in a time- and dose-dependent manner. The entire hemolytic activity of TTE was located in P30, showing 2 peaks of maximum activity, one at pH 6.0 and another at pH 8.0. in the presence of 1 mM Ca2+. Hemolytic activity on rat erythrocytes was greater at pH 6.0 16.71 +/- 0.33 hemolytic units IHU]/mg/hr to 11.60 +/- 0.24 HU/mg/hr) than at pH 8.0 (3.81 +/- 0.30 HU/mg/hr to 5.75 +/- 0.65 HU/mg/hr). and it was greater than that on human red blood cells at pH 6.0 (2.67 +/- 0.19 HU/mg/hr to 4.08 +/- 0.15 HU/mg/hr) or pH 8.0 (2.24 +/- 0.0 9 HU/mg/hr to 2.81 +/- 0.06 HU/mg/hr). The alkaline and acidic hemolytic activity diminished (60-93% at pH 6.0 and 78-93% at pH 8.0) by the effect of 80 microM Rosenthal's inhibitor, which also inhibited 27-45% and 29-54% trichomonad alkaline and acidic phospholipase A activities, respectively. Vesicles, vacuoles, and hydrogenosomes were rich in P30. Trichomonas vaginalis has a hemolytic PLA, which could be involved in its cytopathogenic mechanism.
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Eritrócitos/metabolismo , Hemólise/fisiologia , Fosfolipases A/metabolismo , Trichomonas vaginalis/metabolismo , Animais , Cálcio/metabolismo , Relação Dose-Resposta a Droga , Humanos , Concentração de Íons de Hidrogênio , Fosfolipases A/antagonistas & inibidores , Ratos , Estearatos/farmacologia , Trichomonas vaginalis/enzimologia , Trichomonas vaginalis/patogenicidade , VirulênciaRESUMO
The telomerase is a ribonucleoprotein enzyme to which multiple functions have been attributed, the most important of these is the maintenance of the telomere which is related with cellular immortalization and cancer. 85% of human tumors have telomerase activity, that in normal cells goes undetected. These characteristics make the telomerase an attractive target for chemotherapy.
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Azacitidina/análogos & derivados , Proteínas de Neoplasias/fisiologia , Neoplasias/enzimologia , Telomerase/fisiologia , Antimetabólitos Antineoplásicos/farmacologia , Antimetabólitos Antineoplásicos/uso terapêutico , Azacitidina/farmacologia , Azacitidina/uso terapêutico , Biomarcadores Tumorais , Senescência Celular/genética , Senescência Celular/fisiologia , Decitabina , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Indução Enzimática , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Regulação Neoplásica da Expressão Gênica , Terapia Genética , Humanos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Neoplasias/tratamento farmacológico , Neoplasias/genética , Telomerase/antagonistas & inibidores , Telomerase/química , Telomerase/genética , Telômero/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/enzimologiaRESUMO
Previous studies comparing the expression levels of human placental lactogen (hPL) genes have shown varying results, due to, perhaps, the fact that in all of them only one placenta was being analyzed. Here, the expression of hPL and growth hormone variant (hGH-V) genes in fifteen term placentas was comparatively analyzed at the RNA level, using reverse transciption coupled to polymerase chain reaction (RT-PCR). The abundance of the combined RNA transcripts derived from these genes varied from one placenta to another. The authors found that hPL-4 transcripts were more abundant than those of hPL-3 in most samples (ratio from 1:1 to 6:1), transcripts from the putative hPL-1 pseudogene were more abundant at the unprocessed stage while those of the hGH-V gene were mostly processed. Again, the authors of this study observed wide variation from placenta to placenta to placenta in the abundance of both of these types of transcripts. The same was observed when a group of six placentas from abortuses and nine from pregnancies complicated by preclampsia, diabetes and hypertension was studied. The authors conclude that the disagreeing results reported in the literature which are not in agreement concerning the expression levels of hPL gene could be explained by normal variations of their expression levels among the different placentas analyzed