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Velazquez C, Herrero Y, Bianchi MS, Cohen DJ, Cuasnicu P, Prost K, Marinoni R, Pascuali N, Parborell F, Abramovich D. Beneficial effects of metformin on mice female fertility after a high-fat diet intake. Mol Cell Endocrinol 2023; 575:111995. [PMID: 37364632 DOI: 10.1016/j.mce.2023.111995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 06/08/2023] [Accepted: 06/16/2023] [Indexed: 06/28/2023]
Abstract
Female fertility is highly dependent on energy balance. High fat diet (HFD) intake entails a risk of infertility and ovulatory disorders. Considering the increase in the prevalence of overweight and obesity over the last decades, it is crucial to understand the mechanisms involved in overweight-associated infertility. In this study, we evaluated the reproductive performance of female mice fed with a HFD and the effects of metformin administration on ovarian function in these mice. We hypothesized that one of the mechanisms involved in subfertility due to a HFD intake is the alteration of ovarian blood vessel formation. We found that mice fed with HFD had altered estrous cycles and steroidogenesis, increased ovarian fibrosis, fewer pups per litter and require more time to achieve pregnancy. HFD-fed mice also presented dysregulated ovarian angiogenesis and an increase in nuclear DNA damage in ovarian cells. Ovulation rates were lower in these animals, as evidenced both in natural mating and after ovulation induction with gonadotropins. Metformin ameliorated ovarian angiogenesis, improved steroidogenesis, fibrosis, and ovulation, decreased the time to pregnancy and increased litter sizes in HFD-fed mice. We conclude that ovarian angiogenesis is one of the mechanisms detrimentally affected by HFD intake. Since metformin could improve ovarian microvasculature, it may be an interesting strategy to study in women to shed light on new targets for patients with metabolic disturbances.
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Affiliation(s)
- Candela Velazquez
- Instituto de Biología y Medicina Experimental, IByME-CONICET, Vuelta de Obligado 2490, C1428ADL Ciudad Autónoma de Buenos Aires, Argentina
| | - Yamila Herrero
- Instituto de Biología y Medicina Experimental, IByME-CONICET, Vuelta de Obligado 2490, C1428ADL Ciudad Autónoma de Buenos Aires, Argentina
| | - María Silvia Bianchi
- Instituto de Biología y Medicina Experimental, IByME-CONICET, Vuelta de Obligado 2490, C1428ADL Ciudad Autónoma de Buenos Aires, Argentina
| | - Débora Juana Cohen
- Instituto de Biología y Medicina Experimental, IByME-CONICET, Vuelta de Obligado 2490, C1428ADL Ciudad Autónoma de Buenos Aires, Argentina
| | - Patricia Cuasnicu
- Instituto de Biología y Medicina Experimental, IByME-CONICET, Vuelta de Obligado 2490, C1428ADL Ciudad Autónoma de Buenos Aires, Argentina
| | - Katherine Prost
- Hospital Interzonal General de Agudos Pedro Fiorito, sector de Endocrinología, Av. Manuel Belgrano 827, B1870 Avellaneda, Provincia de Buenos Aires, Argentina
| | - Rocío Marinoni
- Instituto de Biología y Medicina Experimental, IByME-CONICET, Vuelta de Obligado 2490, C1428ADL Ciudad Autónoma de Buenos Aires, Argentina
| | - Natalia Pascuali
- Instituto de Biología y Medicina Experimental, IByME-CONICET, Vuelta de Obligado 2490, C1428ADL Ciudad Autónoma de Buenos Aires, Argentina; Department of Pathology, College of Medicine, University of Illinois at Chicago (UIC), Chicago, IL, United States
| | - Fernanda Parborell
- Instituto de Biología y Medicina Experimental, IByME-CONICET, Vuelta de Obligado 2490, C1428ADL Ciudad Autónoma de Buenos Aires, Argentina
| | - Dalhia Abramovich
- Instituto de Biología y Medicina Experimental, IByME-CONICET, Vuelta de Obligado 2490, C1428ADL Ciudad Autónoma de Buenos Aires, Argentina.
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Castillo MG, Peralta TM, Locatelli P, Velazquez C, Herrero Y, Crottogini AJ, Olea FD, Cuniberti LA. Promoting early neovascularization by allotransplanted adipose-derived Muse cells in an ovine model of acute myocardial infarction. PLoS One 2023; 18:e0277442. [PMID: 36662847 PMCID: PMC9858827 DOI: 10.1371/journal.pone.0277442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 10/26/2022] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Recent preclinical studies have demonstrated that bone marrow (BM)-derived Muse cells have a homing mechanism to reach damaged cardiac tissue while also being able to reduce myocardial infarct size and improve cardiac function; however, the potential of BM-Muse cells to foster new blood-vessel formation has not been fully assessed. Up to date, adipose tissue (AT)-derived Muse cells remain to be studied in acute myocardial infarction (AMI). The aim of the present study was to analyze in vitro and in vivo the neovascularization capacity of AT-Muse cells while exploring their biodistribution and differentiation potential in a translational ovine model of AMI. METHODS AND RESULTS AT-Muse cells were successfully isolated from ovine adipose tissue. In adult sheep, one or more diagonal branches of the left anterior descending coronary artery were permanently ligated for thirty minutes. Sheep were randomized in two groups and treated with intramyocardial injections: Vehicle (PBS, n = 4) and AT-Muse (2x107 AT-Muse cells labeled with PKH26 Red Fluorescent Dye, n = 4). Molecular characterization showed higher expression of angiogenic genes (VEGF, PGF and ANG) and increased number of tube formation in AT-Muse cells group compared to Adipose-derived mesenchymal stromal cells (ASCs) group. At 7 days post-IAM, the AT-Muse group showed significantly more arterioles and capillaries than the Vehicle group. Co-localization of PKH26+ cells with desmin, sarcomeric actin and troponin T implied the differentiation of Muse cells to a cardiac fate; moreover, PKH26+ cells also co-localized with a lectin marker, suggesting a possible differentiation to a vascular lineage. CONCLUSION Intramyocardially administered AT-Muse cells displayed a significant neovascularization activity and survival capacity in an ovine model of AMI.
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Affiliation(s)
- Martha G. Castillo
- Instituto de Medicina Traslacional, Trasplante y Bioingeniería (IMETTYB)—Universidad Favaloro—CONICET, Ciudad de Buenos Aires, Buenos Aires, Argentina
| | - Tomás M. Peralta
- Instituto de Medicina Traslacional, Trasplante y Bioingeniería (IMETTYB)—Universidad Favaloro—CONICET, Ciudad de Buenos Aires, Buenos Aires, Argentina
| | - Paola Locatelli
- Instituto de Medicina Traslacional, Trasplante y Bioingeniería (IMETTYB)—Universidad Favaloro—CONICET, Ciudad de Buenos Aires, Buenos Aires, Argentina
| | - Candela Velazquez
- Instituto de Biología y Medicina Experimental—CONICET, Ciudad de Buenos Aires, Buenos Aires, Argentina
| | - Yamila Herrero
- Instituto de Biología y Medicina Experimental—CONICET, Ciudad de Buenos Aires, Buenos Aires, Argentina
| | - Alberto J. Crottogini
- Instituto de Medicina Traslacional, Trasplante y Bioingeniería (IMETTYB)—Universidad Favaloro—CONICET, Ciudad de Buenos Aires, Buenos Aires, Argentina
| | - Fernanda D. Olea
- Instituto de Medicina Traslacional, Trasplante y Bioingeniería (IMETTYB)—Universidad Favaloro—CONICET, Ciudad de Buenos Aires, Buenos Aires, Argentina
| | - Luis A. Cuniberti
- Instituto de Medicina Traslacional, Trasplante y Bioingeniería (IMETTYB)—Universidad Favaloro—CONICET, Ciudad de Buenos Aires, Buenos Aires, Argentina
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Di Pietro M, Velazquez C, Matzkin ME, Frungieri MB, Peña MG, de Zúñiga I, Pascuali N, Irusta G, Bianchi MS, Parborell F, Abramovich D. Metformin has a direct effect on ovarian cells that is dependent on organic cation transporters. Mol Cell Endocrinol 2020; 499:110591. [PMID: 31546019 DOI: 10.1016/j.mce.2019.110591] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 09/19/2019] [Accepted: 09/20/2019] [Indexed: 12/13/2022]
Abstract
Metformin (MET) is the most widely prescribed hypoglycemic drug in type 2 diabetes and Polycystic Ovary Syndrome. Besides its effects on glucose metabolism, MET exerts beneficial effects on these patients' fertility. However, the exact mechanisms of action of MET on female fertility are still unclear. In this work, we analyzed a possible direct effect of MET on ovarian cells. We found expression of the organic cation transporters OCT1, OCT2 and OCT3, responsible for MET uptake into the cells, in rat granulosa cells and human cumulus cells. Furthermore, MET increased pAMPK and decreased VEGF levels both in vivo and in rat granulosa cells in culture. These last effects were reversed when OCTs were inhibited. Our results suggest that MET acts directly on ovarian cells regulating cell metabolism and VEGF expression. Our findings are relevant to optimize PCOS fertility treatment and to explore ovarian MET actions in other female pathologies.
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Affiliation(s)
- Mariana Di Pietro
- Instituto de Biología y Medicina Experimental-Consejo Nacional de Investigaciones Científicas y Técnicas (IByME-CONICET), Ciudad Autónoma de Buenos Aires, Argentina
| | - Candela Velazquez
- Instituto de Biología y Medicina Experimental-Consejo Nacional de Investigaciones Científicas y Técnicas (IByME-CONICET), Ciudad Autónoma de Buenos Aires, Argentina
| | - María Eugenia Matzkin
- Instituto de Biología y Medicina Experimental-Consejo Nacional de Investigaciones Científicas y Técnicas (IByME-CONICET), Ciudad Autónoma de Buenos Aires, Argentina
| | - Mónica Beatriz Frungieri
- Instituto de Biología y Medicina Experimental-Consejo Nacional de Investigaciones Científicas y Técnicas (IByME-CONICET), Ciudad Autónoma de Buenos Aires, Argentina; Cátedra de Química, Ciclo Básico Común, Universidad de Buenos Aires, Ciudad de Buenos Aires, Argentina
| | - Mariana Gómez Peña
- Centro Médico Pregna Medicina Reproductiva. Ciudad Autónoma de Buenos Aires, Argentina
| | - Ignacio de Zúñiga
- Centro Médico Pregna Medicina Reproductiva. Ciudad Autónoma de Buenos Aires, Argentina
| | - Natalia Pascuali
- Instituto de Biología y Medicina Experimental-Consejo Nacional de Investigaciones Científicas y Técnicas (IByME-CONICET), Ciudad Autónoma de Buenos Aires, Argentina
| | - Griselda Irusta
- Instituto de Biología y Medicina Experimental-Consejo Nacional de Investigaciones Científicas y Técnicas (IByME-CONICET), Ciudad Autónoma de Buenos Aires, Argentina
| | - María Silvia Bianchi
- Instituto de Biología y Medicina Experimental-Consejo Nacional de Investigaciones Científicas y Técnicas (IByME-CONICET), Ciudad Autónoma de Buenos Aires, Argentina
| | - Fernanda Parborell
- Instituto de Biología y Medicina Experimental-Consejo Nacional de Investigaciones Científicas y Técnicas (IByME-CONICET), Ciudad Autónoma de Buenos Aires, Argentina
| | - Dalhia Abramovich
- Instituto de Biología y Medicina Experimental-Consejo Nacional de Investigaciones Científicas y Técnicas (IByME-CONICET), Ciudad Autónoma de Buenos Aires, Argentina.
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Lopez-Romero G, Quintero J, Astiazarán-García H, Velazquez C. Host defences againstGiardia lamblia. Parasite Immunol 2015; 37:394-406. [DOI: 10.1111/pim.12210] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 06/08/2015] [Indexed: 02/06/2023]
Affiliation(s)
- G. Lopez-Romero
- Coordinación de Nutrición; Centro de Investigación en Alimentación y Desarrollo A.C.; Hermosillo Sonora México
| | - J. Quintero
- Department of Chemistry-Biology; University of Sonora; Hermosillo Sonora México
| | - H. Astiazarán-García
- Coordinación de Nutrición; Centro de Investigación en Alimentación y Desarrollo A.C.; Hermosillo Sonora México
| | - C. Velazquez
- Department of Chemistry-Biology; University of Sonora; Hermosillo Sonora México
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Perez-Lloret S, Rojas GM, Menoni M, Ruiz G, Velazquez C, Rodriguez H, Rey M, Cardinali D. Pregabalin beneficial effects on sleep quality or health-related quality of life are poorly correlated with reduction on pain intensity. J Neurol Sci 2013. [DOI: 10.1016/j.jns.2013.07.1844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Ruiz-Bustos E, Velazquez C, Garibay-Escobar A, García Z, Plascencia-Jatomea M, Cortez-Rocha M, Hernandez-Martínez J, Robles-Zepeda R. Antibacterial and Antifungal Activities of Some Mexican Medicinal Plants. J Med Food 2009; 12:1398-402. [DOI: 10.1089/jmf.2008.0205] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- E. Ruiz-Bustos
- Cuerpo Académico Biología y Bioquímica, Departamento de Ciencias Químico Biológicas, Universidad de Sonora, Hermosillo, Sonora
| | - C. Velazquez
- Cuerpo Académico Biología y Bioquímica, Departamento de Ciencias Químico Biológicas, Universidad de Sonora, Hermosillo, Sonora
| | - A. Garibay-Escobar
- Cuerpo Académico Biología y Bioquímica, Departamento de Ciencias Químico Biológicas, Universidad de Sonora, Hermosillo, Sonora
| | - Z. García
- Cuerpo Académico Biología y Bioquímica, Departamento de Ciencias Químico Biológicas, Universidad de Sonora, Hermosillo, Sonora
| | - M. Plascencia-Jatomea
- Laboratorio de Micotoxinas, Departamento de Investigación y Posgrado en Alimentos, Universidad de Sonora, Hermosillo, Sonora
| | - M.O. Cortez-Rocha
- Laboratorio de Micotoxinas, Departamento de Investigación y Posgrado en Alimentos, Universidad de Sonora, Hermosillo, Sonora
| | - J. Hernandez-Martínez
- Unidad de Servicios de Apoyo en Resolución Analítica, Universidad Veracruzana, Xalapa, Veracruz, México
| | - R.E. Robles-Zepeda
- Cuerpo Académico Biología y Bioquímica, Departamento de Ciencias Químico Biológicas, Universidad de Sonora, Hermosillo, Sonora
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Astiazaran-Garcia H, Quintero J, Vega R, Briceño P, Oviedo C, Rascon L, Garibay-Escobar A, Castillo-Yañez FJ, Robles-Zepeda R, Hernandez J, Velazquez C. Identification of T-cell stimulating antigens from Giardia lamblia by using Giardia-specific T-cell hybridomas. Parasite Immunol 2009; 31:132-9. [PMID: 19222784 DOI: 10.1111/j.1365-3024.2008.01083.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
T-cell immune response plays an important role in controlling Giardia lamblia infections. Little is known about the G. lamblia-specific antigens that stimulate a cell-mediated immune response. The aim of the present study was to identify T-cell stimulating G. lamblia antigens. For this purpose, we generated a group of Giardia-specific T-cell hybridomas (2F9, 4D5, 6D10, 8B9, 9B10, 10F7 and 10G5). Hybridomas were screened for reactivity with G. lamblia protein extract by the CTLL bioassay. These T-cell hybridomas did not exhibit any significant activation either in the absence of G. lamblia protein extract or in the presence of irrelevant antigen (hen white egg lysozyme). To further characterize the T-cell hybridomas generated, we selected three hybridomas (10G5, 4D5 and 9B10). Giardia lamblia proteins of 90-110, 65-77 and 40-64 kDa showed T-cell stimulating activity for the hybridomas 10G5, 4D5 and 9B10, respectively, in a concentration-dependent manner. Protein extract obtained from different G. lamblia strains (GS/M-83-H7, WB C6 and a clinical isolate (YJJ)) stimulated all T-cell hybridomas, indicating that T-cell-stimulating antigens are expressed among different G. lamblia strains. In conclusion, we identified T-cell stimulating G. lamblia antigens by using Giardia-specific T-cell hybridomas. To our knowledge, these hybridomas are the first-described T-cell hybridomas specific for G. lamblia.
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Affiliation(s)
- H Astiazaran-Garcia
- Centro de Investigación en Alimentación y Desarrollo A.C. Hermosillo, Sonora, México
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Velazquez C, Navarro M, Acosta A, Angulo A, Dominguez Z, Robles R, Robles-Zepeda R, Lugo E, Goycoolea FM, Velazquez EF, Astiazaran H, Hernandez J. Antibacterial and free-radical scavenging activities of Sonoran propolis. J Appl Microbiol 2008; 103:1747-56. [PMID: 17953585 DOI: 10.1111/j.1365-2672.2007.03409.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS To evaluate the antibacterial and free-radical scavenging (FRS) activities of propolis collected from three different areas of Sonoran Desert in northwestern Mexico [Pueblo de Alamos (PAP), Ures (UP) and Caborca (CP)]. METHODS AND RESULTS The antibacterial and FRS activities of Sonoran propolis were determined by the broth microdilution method and the DPPH (1,1-diphenyl-2-picrylhydracyl) assay, respectively. Propolis samples had antibacterial activity against only Gram-positive bacteria. The UP sample showed the highest antibacterial activity against Staphylococcus aureus [minimal inhibitory concentration (MIC) 100 microg ml(-1)] in a concentration-dependent manner (UP > CP > PAP). Caffeic acid phenethyl ester (CAPE), a UP propolis constituent, had very high growth-inhibitory activity towards Gram-positive bacteria, particularly against S. aureus (MIC 0.1 mmol l(-1)). To our knowledge, this is the first study showing a strong antibacterial activity of CAPE against S. aureus. Additionally, propolis CP exhibited high FRS activity (86% +/- 0.3 at 100 microg ml(-1)) comparable with those of the reference antioxidants vitamin C (87.4% +/- 1.7 at 70 micromol l(-1)) and BHT (66.07% +/- 0.76 at 140 micromol l(-1)). The propolis compounds CAPE and rutin showed high FRS activity (90.4% +/- 0.2 and 88.5% +/- 0.8 at 70 micromol l(-1), respectively). CONCLUSIONS Sonoran propolis UP and CAPE had strong antibacterial activity against S. aureus. In addition, propolis CP showed potent FRS activity comparable with those of vitamin C and BHT. SIGNIFICANCE AND IMPACT OF THE STUDY The strong antibacterial and antioxidant properties of Sonoran propolis and some of its constituents support further studies on the clinical applications of this natural bee product against S. aureus and several oxidative damage-related diseases.
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Affiliation(s)
- C Velazquez
- Department of Chemistry-Biology, University of Sonora, Hermosillo, Sonora, Mexico
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9
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Velazquez C, Beltran M, Ontiveros N, Rascon L, Figueroa DC, Granados AJ, Hernandez-Martinez J, Hernandez J, Astiazaran-Garcia H. Giardia lamblia infection induces different secretory and systemic antibody responses in mice. Parasite Immunol 2005; 27:351-6. [PMID: 16149993 DOI: 10.1111/j.1365-3024.2005.00793.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The adult mouse model of Giardia lamblia infection serves as an excellent animal model to understand the immunological mechanisms involved in the control and clearance of Giardia infection. Little is known about the G. lamblia-specific antigens that stimulate the humoral immune response in this model of giardiasis. We analysed the secretory and systemic antibody responses to G. lamblia during primary and secondary infection in C3H/HeJ adult mice. Faecal IgA and Serum IgG anti-G. lamblia antibodies were observed at week 2 post-infection. Serum IgG responses remained constant over the next several weeks, whereas faecal IgA titres continued to rise from weeks 2-6 post-infection. Western blot analysis revealed that intestinal IgA and serum IgG antibody responses were directed toward several distinct proteins of G. lamblia. Certain proteins appeared to be recognized by both faecal IgA and serum IgG, whereas other antigens were specific for either the secretory or systemic antibody responses. G. lamblia primary and secondary infections were associated with differences in the antibody recognition pattern. The biochemical and immunological characterization of these antigens will help us to better understand the immunobiology of the G. lamblia-host interaction.
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Affiliation(s)
- C Velazquez
- Department of Chemistry-Biology, University of Sonora, Hermosillo, Sonora, México.
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Abstract
Pharmacokinetic variables of amikacin in cows were determined after administration of amikacin sulphate either intravenously (IV) or intramuscularly (IM) at a dose of 25 mg/kg per day for three days. Amikacin concentrations at time zero and maximum serum concentrations were 240.8 microg/mL and 122.53 microg/mL, respectively. The elimination half-life remained unchanged during the three days of administration (T1/2beta = 1.33 +/- 0.029 h for the IV route and T1/2beta = 2.75 +/- 0.38 h for the IM route). Apparent volumes of distribution suggest limited distribution out of the central compartment (VdAUC = 0.154 +/- 0.005 L/kg; Vdc = 36.50 +/- 2.35 L; Vdss = 0.092 +/- 0.004 L/kg). Bioavailability after IM administration was 95%. Serum profiles of urea, creatinine, albumin, electrolytes and pH after 5-day treatment with amikacin at a dose of 25 mg/kg per day IM revealed no changes. Assessment of diffusion of amikacin to milk by a commercially available screening method to detect antibiotic residues revealed that amikacin could not be detected by the fifth milking period after the last treatment. These results suggest that it would be rational to use a large single-daily dose of amikacin for future clinical trials in cows.
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Affiliation(s)
- H Sumano
- Department of Physiology and Pharmacology, School of Veterinary Medicine, National Autonomous University of Mexico, Mexico City 04510, Mexico.
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Rubner MF, Sandman DJ, Velazquez C. On the structural origin of the thermochromic behavior of urethane-substituted poly(diacetylenes). Macromolecules 2002. [DOI: 10.1021/ma00172a023] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Velazquez C, Carlson A, Stokes KA, Leikin JB. Relative safety of mirtazapine overdose. Vet Hum Toxicol 2001; 43:342-4. [PMID: 11757992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
A 43-y-o male with a history of AIDS, atrial fibrillation, and alcohol abuse presented to the emergency department 2 h after ingestion of 25 tablets of 15 mg mirtazapine (total 375 mg) with ethanol in a suicide attempt (no other coingestion). Vital signs were normal except for a mild tachycardia (rate 112). Physical examination was unremarkable except for lethargy. Fifty grams of activated charcoal with sorbitol was given. Electrocardiogram showed sinus tachycardia, left ventricular hypertrophy, and non-specific ST-segment changes. Serum mirtazapine on admission was 530 ng/mL (therapeutic level 20-50 ng/mL). Overnight monitoring revealed no tachyarrythmias, and discharge occurred after psychiatric evaluation. It appears that ingestions of mirtazapine approximately 10-fold of therapeutic exhibit minimal acute toxicity. From this and other cases in the literature exhibiting a 10-fold overdose, we conclude that isolated mirtazapine ingestions of this magnitude require no acute intervention other than short term (about 6 h) observation.
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Affiliation(s)
- C Velazquez
- Washington University, St Louis, MO 63110, USA
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13
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Velazquez C, DiPaolo R, Unanue ER. Quantitation of lysozyme peptides bound to class II MHC molecules indicates very large differences in levels of presentation. J Immunol 2001; 166:5488-94. [PMID: 11313387 DOI: 10.4049/jimmunol.166.9.5488] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Knowing the abundance of peptides presented by MHC molecules is a crucial aspect for understanding T cell activation and tolerance. In this report we determined the relative abundance of four distinct peptide families after the processing of the model Ag hen egg-white lysozyme. The development of a sensitive immunochemical approach reported here made it possible to directly quantitate the abundance of these four epitopes presented by APCs, both in vitro and in vivo. We observed a wide range of presentation among these four different epitopes presented on the surface of APCs, with 250-fold differences or more between the most abundant epitope (48-63) and the least abundant epitopes. Importantly, we observe similar ratios of presentation from APCs in vitro as well as from APCs from the spleens and thymi of hen egg-white lysozyme transgenic mice. We discuss the relationship between the amount of peptide presented and their binding to I-A(k) molecules, immunogenicity, and tolerogenicity.
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Affiliation(s)
- C Velazquez
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
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Gugasyan R, Velazquez C, Vidavsky I, Deck BM, van der Drift K, Gross ML, Unanue ER. Independent selection by I-Ak molecules of two epitopes found in tandem in an extended polypeptide antigen. J Immunol 2000; 165:3206-13. [PMID: 10975836 DOI: 10.4049/jimmunol.165.6.3206] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The protein hen egg white lysozyme (HEL) contains two segments, in tandem, from which two families of peptides are selected by the class II molecule I-Ak, during processing. These encompass peptides primarily from residues 31-47 and 48-63. Mutant HEL proteins were created with changes in residues 52 and 55, resulting in a lack of binding and selection of the 48-63 peptides to I-Ak molecules. Such mutant HEL proteins donated the same amount of 31-47 peptide as did the unmodified protein. Other mutant HEL molecules containing proline residues at residue 46, 47, or 48 resulted in extensions of the selected 31-47 or 48-62 families to their overlapping regions (in the carboxyl or amino termini, respectively). However, the amount of each family of peptide selected was not changed. We conclude that the presence or absence of the major peptide from HEL does not influence the selection of other epitopes, and that these two families are selected independently of each other.
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Affiliation(s)
- R Gugasyan
- Departments of Pathology and Immunology and Chemistry, Washington University School of Medicine, St. Louis, MO 63110, USA
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Velazquez C, Shibayama-Salas M, Aguirre-Garcia J, Tsutsumi V, Calderon J. Role of neutrophils in innate resistance to Entamoeba histolytica liver infection in mice. Parasite Immunol 1998; 20:255-62. [PMID: 9651927 DOI: 10.1046/j.1365-3024.1998.00128.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In order to define the role of neutrophils in the innate resistance to Entamoeba histolytica liver infection in mice, we examined the pattern of liver lesion induced by direct injection of E. histolytica trophzoites in normal mice and in neutrophil-depleted mice. A variety of histological lesions were found, the extent of liver damage was considerably higher in the neutrophil-depleted mice. Livers from neutrophil-depleted mice displayed areas of liquefactive (lytic) necrosis containing a large number of amoebae and absence of neutrophils or mononuclear cells. By contrast, in the liver of normal mice, neutrophils were seen associated to E. histolytica at early stages of infection. In both mouse groups, areas of TUNEL-positive dead hepatocytes were observed and a characteristic internucleosomal banding pattern of genomic DNA consistent with apoptosis was detected in DNA harvested from amoebic liver lesions. These data suggest that neutrophils play an important role in the mechanisms of resistance to amoebic liver infection in mice. In addition, our histological analysis suggests that E. histolytica is capable of producing liver damage in the absence of inflammatory cells.
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Affiliation(s)
- C Velazquez
- Department of Cell Biology, CINVESTAV, Mexico DF
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Velazquez C, Valette I, Cruz M, Labra ML, Montes J, Stanley SL, Calderon J. Identification of immunogenic epitopes of the 170-kDa subunit adhesin of Entamoeba histolytica in patients with invasive amebiasis. J Eukaryot Microbiol 1995; 42:636-41. [PMID: 7581341 DOI: 10.1111/j.1550-7408.1995.tb05920.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Entamoeba histolytica causes amebic dysentery (AD) and liver abscess (ALA). Little is known about protective immunity to amebiasis, and studies in this area have been complicated by the paucity of defined ameba antigens. We examined the proliferative responses of peripheral blood mononuclear cells (PBMC) from patients with AD and ALA to a recombinant protein containing a portion of the 170 kDa adhesin of E. histolytica (170CR), and to two synthetic peptides (1 and 2) derived from the 170 kDa sequence that were predicted to contain T cell epitopes. A significant number of patients with AD and ALA had PBMC that proliferated to 170CR molecule, and several individuals with ALA and AD had T cells that recognized one or both peptides. Contrarily, individuals from a non-endemic region for amebiasis did not respond to 170CR protein, or to both peptides. In regard to antibody response, nine of fifteen patients with ALA showed antibodies to 170CR protein. These same patients had antibodies to peptide 2. We identified peptides from 170-kDa adhesin that may contain both T and B cell epitopes recognized by some patients with invasive amebiasis. These peptides may be valuable reagents in studies of the immune response to amebiasis.
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Affiliation(s)
- C Velazquez
- Department of Cell Biology, CINVESTAV, Mexico, D.F., Mexico
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