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Meier-Girard D, Tibi A, Abdoul H, Prot-Labarthe S, Brion F, Bourdon O, Alberti C. Academic pediatric clinical research: factors associated with study implementation duration. BMC Med Res Methodol 2016; 16:36. [PMID: 27025840 PMCID: PMC4812626 DOI: 10.1186/s12874-016-0138-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 03/18/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The ethical, methodological, and technical aspects of pediatric research, often results in complications and delays in implementation. Our objective was to identify factors associated with the implementation duration of hospital-based pediatric studies. METHODS All hospital-based pediatric studies sponsored by AP-HP between 2002 and 2008 were retrospectively identified. Association of the funding mechanism and methodological factors with the implementation duration was assessed using a multivariable mixed linear model. Pharmaceutical factors were explored as part of a subgroup analysis restricted to the studies involving drug therapy. Given that we took an exploratory approach, factors associated with implementation duration with p < 0.10 were kept in the final models. RESULTS A total of 139 studies were evaluated. The median implementation duration was 17.1 months (range: 0.9-55.3 months), and tended to increase over time (from 14.9 [25(th) percentile-75(th) percentile: 11.5-19.9] months in 2002 to 23.7 [15.2-31.0] months in 2008, p = 0.01). External (coefficient [95 % confidence interval]: -7.7 [-11.9;-3.5] months, p < 0.001) and internal funding (-5.3 95 % CI [-9.8;-0.8], p = 0.02) compared to governmental funding and number of centers (-0.1 95 % CI[-0.2;0.02] months for 1 center increase, p = 0.07) were associated with reduced duration, whereas interventional study (either involving drug therapy (6.0 95 % CI[0.7;11.3] months, p = 0.03 or not (3.5 95 % CI[-0.3;7.3] months, p = 0.06) was associated with increased duration compared to observational study. Regarding the 35 studies involving drug therapy, external funding decreased duration (-6.7 95 % CI[-13.2;-0.2] months, p = 0.05), whereas studies involving solely a pediatric population (7.8 95 % CI[1.1;14.5] months, p = 0.01) (compared to mixed adult-pediatric population), a placebo-controlled design (6.6 95 % CI[0.9;12.3] months, p = 0.01), and inappropriate drug formulation for at least one drug used in the study (6.9 95 % CI[-0.2;14.0] months, p = 0.06) were associated with increased duration. CONCLUSION Implementation of hospital-based pediatric studies primarily faced delays when they were interventional and, in particular, when they involved drug therapy. Regarding the latter, difficulties that resulted in delayed studies arose with respect to the supply of drugs and placebo in age-appropriate dosages and route of administration. Therefore, difficulties related to the use of pharmaceuticals need to be anticipated earlier in order to avoid implementation delays.
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Affiliation(s)
- Delphine Meier-Girard
- />Université Paris Diderot, Sorbonne Paris Cité, UMR-1123 ECEVE, F-75019 Paris, France
- />AP-HP, Hôpital Robert Debré, Unité d’Epidémiologie Clinique, F-75019 Paris, France
- />Inserm, U1123 and CICEC 1426, F-75019 Paris, France
- />University of Basel, University Children’s Hospital (UKBB), Basel, Switzerland
- />Department of Paediatric Pulmonology, University Children`s Hospital Basel (UKBB), Spitalstrasse 33, 4056 Basel, Switzerland
| | - Annick Tibi
- />Université Paris Descartes, Sorbonne Paris Cité, F-75270 Paris, France
- />Département d’Essais Cliniques, AP-HP, Agence Générale des Equipements et Produits de Santé, F-75013 Paris, France
| | - Hendy Abdoul
- />Université Paris Diderot, Sorbonne Paris Cité, UMR-1123 ECEVE, F-75019 Paris, France
- />AP-HP, Hôpital Robert Debré, Unité d’Epidémiologie Clinique, F-75019 Paris, France
- />Inserm, U1123 and CICEC 1426, F-75019 Paris, France
| | - Sonia Prot-Labarthe
- />Université Paris Diderot, Sorbonne Paris Cité, UMR-1123 ECEVE, F-75019 Paris, France
- />Inserm, U1123 and CICEC 1426, F-75019 Paris, France
- />AP-HP, Hôpital Robert Debré, Pharmacie à Usage Intérieur, F-75019 Paris, France
| | - Françoise Brion
- />Université Paris Descartes, Sorbonne Paris Cité, F-75270 Paris, France
- />AP-HP, Hôpital Robert Debré, Pharmacie à Usage Intérieur, F-75019 Paris, France
| | - Olivier Bourdon
- />Université Paris Descartes, Sorbonne Paris Cité, F-75270 Paris, France
- />AP-HP, Hôpital Robert Debré, Pharmacie à Usage Intérieur, F-75019 Paris, France
| | - Corinne Alberti
- />Université Paris Diderot, Sorbonne Paris Cité, UMR-1123 ECEVE, F-75019 Paris, France
- />AP-HP, Hôpital Robert Debré, Unité d’Epidémiologie Clinique, F-75019 Paris, France
- />Inserm, U1123 and CICEC 1426, F-75019 Paris, France
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Fayemi PO, Muchenje V. Maternal slaughter at abattoirs: history, causes, cases and the meat industry. SPRINGERPLUS 2013; 2:125. [PMID: 23577300 PMCID: PMC3618883 DOI: 10.1186/2193-1801-2-125] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 03/04/2013] [Indexed: 11/10/2022]
Abstract
Animals of both sexes are slaughtered for meat and meat products at the abattoirs. It has been found in few countries that one-out-of-every-three ewe and one-out-of-every-four doe with single, twin or multiple foetuses are slaughtered in registered slaughterhouses. In quest for meat, numerous viable embryos and foetuses are wasted unnoticed since the productive pregnant animals are not spared in the process. The trend in the slaughter of pregnant animals for meat (ranging from 54.5% to 70.1%) therefore calls for a review to reminisce issues on slaughter reforms, emphasize its implication on losses of genetic materials and sustainability of meat production. As a way of ensuring that welfare quality® assessment is not compromised and cruelty is prevented during animal slaughter, the quantitation of housekeeping genes and naturally occurring microRNAs (miRNAs) are recommended for identifying candidate pain biomarkers. In order to respect consumers’ right however, the manuscript suggests meat branding where the consumption of meat from pregnant animals is ethical.
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Affiliation(s)
- Peter Olutope Fayemi
- Department of Livestock and Pasture Science, University of Forte Hare, Private Bag X1314, Alice, Eastern Cape, 5700 South Africa
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[Advances on progesterone receptor gene]. YI CHUAN = HEREDITAS 2008; 30:1536-44. [PMID: 19073566 DOI: 10.3724/sp.j.1005.2008.01536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The steroid hormone, progesterone, plays a key role in diverse events associated with female reproduction. In humans and other vertebrates, the biological activity of progesterone is mediated by modulation of the transcriptional activity of two progesterone receptors, PGR-A and PGR-B. This review introduced the structure, expression regulation and polymorphism of progesterone receptor gene. The relationship between progesterone receptor gene and reproductive function was also discussed in mammals.
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Pfister P, Geissbuehler U, Wiener D, Hirsbrunner G, Kaufmann C. Pollakisuria in a dwarf goat due to pathologic enlargement of the uterus. Vet Q 2007; 29:112-6. [PMID: 17970288 DOI: 10.1080/01652176.2007.9695234] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022] Open
Abstract
Pollakisuria in adult goats can be caused by diseases of the urinary tract and by distension of parts of the genital tract leading to irritation of the bladder. Hydrometra is the most common cause of uterine distension in goats and usually can be resolved by prostaglandin injections. But other pathologies of the uterus can generate a similar syndrome. A dwarf goat was presented at the clinic with a history of chronic pollakisuria and tenesm. An initial ultrasonographic examination of the abdomen led to the suspicion of hydrometra, but treatment with injections of prostaglandin were not successful. Blood samples revealed low progesterone and high oestrogen values. A laparotomy was performed and an enlarged uterus with 1.5 L of mucous content and cystic ovaries were found and partially removed. A single solid leiomyoma was diagnosed histologically in the uterine wall. Two months later the goat's condition had deteriorated and therefore she was euthanized. Necropsy and pathohistological examination revealed the presence of a metastasized adenocarcinoma of the uterus. In this case, the pollakisuria provoqued by distension of the uterus was not caused by hydrometra, but by neoplasia. The syndrome and the pathogenesis of the adenocarcinoma in consideration of the hormonal status of the patient is discussed.
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Affiliation(s)
- P Pfister
- Clinic for Ruminants, Vetsuisse-Faculty of Bern, University of Bern, Switzerland.
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Abduch MCD, Assad RS, Rodriguez MQ, Valente AS, Andrade JL, Demarchi LMM, Marcial MB, Aiello VD. Reversible pulmonary trunk banding III: Assessment of myocardial adaptive mechanisms—contribution of cell proliferation. J Thorac Cardiovasc Surg 2007; 133:1510-6. [PMID: 17532949 DOI: 10.1016/j.jtcvs.2006.12.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2006] [Revised: 11/20/2006] [Accepted: 12/13/2006] [Indexed: 10/23/2022]
Abstract
OBJECTIVES Rapid ventricular conditioning induced by pulmonary artery banding has been recommended for patients with transposition of the great arteries who have lost the chance for the arterial switch operation or whose systemic (right) ventricle failed after the atrial switch. The present study was designed to experimentally evaluate 2 types of pulmonary artery banding (continuous and intermittent) and verify histologically the changes (hypertrophy or hyperplasia or both) of cardiomyocytes and vascular and interstitial cells from the stimulated ventricle beyond the neonatal period. METHODS Twenty-one goats, 30 to 60 days old, were divided into 3 groups, each comprising 7 animals, as follows: control group (no surgical procedure); continuously stimulated group (systolic overload maintained for 96 hours); and intermittently stimulated group (4 periods of 12-hour systolic overload, alternated with a resting period of 12 hours). The animals were then killed for histologic and immunohistochemical analysis of the hearts. Murine monoclonal antibody Ki-67 was used as a proliferation cell marker. Myocardial collagen area fraction was determined by Sirius red staining. RESULTS For both stimulated groups, a significant increase occurred in right ventricular cardiomyocytes and respective nuclei diameters compared with the controls (P < .05). The number of Ki-67-positive cardiomyocytes and interstitial/vessel cells from the right ventricle was augmented in both trained groups in relation to the left ventricle (P < .05). There was no significant difference in the right ventricular collagen area fraction from both trained groups compared with controls. CONCLUSIONS Irrespective of the shorter training time (periods of overload intercalated with resting), the intermittent stimulation regimen was able to produce a similar training of the subpulmonary ventricle compared with the continuous stimulation regarding mass acquisition, cell hypertrophy, and hyperplasia.
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Affiliation(s)
- Maria C D Abduch
- Laboratory of Pathology, Heart Institute (InCor) University of Sao Paulo Medical School, Sao Paulo, Brazil
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Anzaldúa SR, Camacho-Arroyo I, Reyna-Neyra A, Pérez-Martínez M, Cerbón M. Regional differences in expression of progesterone receptor in oviduct and uterus of rabbit during early pregnancy. Comp Biochem Physiol A Mol Integr Physiol 2006; 147:685-690. [PMID: 16931081 DOI: 10.1016/j.cbpa.2006.06.031] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2006] [Revised: 06/15/2006] [Accepted: 06/17/2006] [Indexed: 11/19/2022]
Abstract
We characterized the expression pattern of progesterone receptor (PR) in two regions of the oviduct (ampullae and isthmus), and the uterus (epithelium and stroma) of the rabbit (Oryctolagus cuniculus) during early pregnancy (1-4 days) by RT-PCR and immunohistochemistry. We observed a significant increase in the expression of PR at mRNA level in the uterus on days 1 and 2 of pregnancy, followed by a decrease on days 3 and 4. These changes were also observed at protein level in the uterine epithelium. Interestingly, PR immunoreactivity decreased in stromal cells in all days of pregnancy as compared with non-pregnant rabbits (NG). In the isthmus PR mRNA expression significantly increased on day 2 of pregnancy and diminished on days 3 and 4, whereas no significant changes were observed in the ampullae. In epithelial and stromal cells of the isthmus, PR immunostaining was reduced through pregnancy as compared with NG group. In contrast, a reduction in PR immunostaining was observed on days 1-3 with an increase on day 4 in epithelial and stromal cells of the ampullae. The overall results suggest that PR exhibit a differential expression pattern in the oviduct and the uterus during early pregnancy of the rabbit, and that these differences are related to different functions of PR in the reproductive tract during early pregnancy.
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Affiliation(s)
- Santiago René Anzaldúa
- Laboratorio de Biología Tisular de la Reproducción, Departamento de Morfología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, México, D. F., México
| | - Ignacio Camacho-Arroyo
- Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán 04510, México, D. F., México
| | - Andrea Reyna-Neyra
- Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán 04510, México, D. F., México
| | - Mario Pérez-Martínez
- Laboratorio de Biología Tisular de la Reproducción, Departamento de Morfología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, México, D. F., México
| | - Marco Cerbón
- Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán 04510, México, D. F., México.
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García-Palencia P, Sánchez MA, Nieto A, Vilar MP, González M, Veiga-Lopez A, González-Bulnes A, Flores JM. Sex steroid receptor expression in the oviduct and uterus of sheep with estrus synchronized with progestagen or prostaglandin analogues. Anim Reprod Sci 2006; 97:25-35. [PMID: 16466867 DOI: 10.1016/j.anireprosci.2006.01.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2005] [Revised: 12/26/2005] [Accepted: 01/04/2006] [Indexed: 11/15/2022]
Abstract
The objective of this study was to investigate differences in the expression of estrogen receptor-alpha (ERalpha), progesterone receptor (PR) and the proliferative indexes (Ki-67), in the uterus and oviduct of sheep with estrus synchronized either by prostaglandin analogues (Group PA, n=27) or by treatment with progestagens (Group P, n=29) on days 4 and 7 (day 0=estrus), when the embryos were collected. Immunohistochemical methods were used to quantify ERalpha, PR and Ki-67 in six superficial and deep compartments in the uterus and oviduct. The expression of ERalpha was significantly (P<0.01) lower in progestagen treated ewes than in prostaglandin analogues treated group in the luminal epithelium, superficial glands and superficial stroma in the uterus on day 4. The expression of PR was significantly lower in progesterone treated ewes than in the PA Group in the superficial gland (P<0.05) in both days studied. The lowest expression of PR was observed in the luminal caruncular epithelium and superficial glands in both treatments, obtaining the lowest levels on day 4 (P<0.05). There were significant differences between days 4 and 7 in the Ki-67 immunostaining in the luminal epithelium (P<0.01) and superficial glands (P<0.05). A higher cell proliferation was observed in the uterine epithelium (P<0.05) on day 4 in the animals treated with progestagens. Results indicate that sheep with synchronization of estrus with progestagens showed a reduction of ERalpha and PR protein expression in most of oviductal and uterine cells.
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Affiliation(s)
- P García-Palencia
- Departamento de Medicina y Cirugía Animal, Facultad de Veterinaria, UCM, Avda. Puerta de Hierro s/n, 28040 Madrid, Spain
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Boos A, Kohtes J, Janssen V, Mülling C, Stelljes A, Zerbe H, Hässig M, Thole HH. Pregnancy effects on distribution of progesterone receptors, oestrogen receptor α, glucocorticoid receptors, Ki-67 antigen and apoptosis in the bovine interplacentomal uterine wall and foetal membranes. Anim Reprod Sci 2006; 91:55-76. [PMID: 15885934 DOI: 10.1016/j.anireprosci.2005.03.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2004] [Revised: 02/25/2005] [Accepted: 03/11/2005] [Indexed: 11/24/2022]
Abstract
Until recently, studies dealing with the uterus of the pregnant cow focus primarily on the placentome or on early and late pregnancy. Thus, there is a paucity of information about many aspects of the interplacentomal uterine wall including adherent foetal membranes. Corresponding tissue specimens were collected at the slaughterhouse and in animals undergoing premature caesarean section. Two specimens per month of pregnancy were assessed immunohistochemically for progesterone receptors, oestrogen receptor alpha and glucocorticoid receptors, Ki-67 protein and TUNEL procedure was performed. The latter two methods were employed in three animals each per months 1 and 2, 3 and 4, 7 and 8 and in six animals undergoing caesarean section at days 274 and 275 post insemination or during spontaneous labour. Results indicate that proliferation and apoptosis are of minor importance for tissue homeostasis since both can histochemically be detected only sporadically. Thus, at the sites investigated here, cellular hypertrophy plays an important role for tissue growth during pregnancy. Progesterone receptors, oestrogen receptor alpha and glucocorticoid receptors, however, exhibit cell type and pregnancy stage specific distribution patterns within the tissues assessed. Progesterone receptor immunoreactive scores remained fairly unchanged during pregnancy. Oestrogen receptor alpha scores, however, generally decreased and glucocorticoid receptors increased with ongoing gestation. Progesterone receptors and oestrogen receptor alpha were present in endometrial stroma and in myometrial smooth muscle cells during whole pregnancy. Oestrogen receptor alpha was detectable during whole pregnancy also in uterine glands. Progesterone receptors were, however, present at a very low level at the latter site only during months 1-3 and 6-9. Oestrogen receptor alpha and glucocorticoid receptors may also mediate uterine blood flow since they were present in the tunica media of uterine blood vessels. Results of the present study indicate, that progesterone and its receptor play an important role during whole gestation, mainly for uterine quiescence. Glucocorticoids and their receptors - possibly in cooperation with oestrogens and decreasing amounts of the oestrogen receptor alpha - should trigger processes initiating parturition, such as endometrial prostaglandin production. Further studies - including the periparturient period - should help to understand the exact role of the extraplacental compartment of the uterine wall for the initiation and progress of parturition.
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Affiliation(s)
- A Boos
- Institute of Veterinary Anatomy, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057 Zurich, Switzerland.
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Sukjumlong S, Persson E, Kaeoket K, Dalin AM. Immunohistochemical Studies on Oestrogen Receptor Alpha (ERα) and the Proliferative Marker Ki-67 in the Sow Uterus at Oestrus and Early Pregnancy. Reprod Domest Anim 2004; 39:361-9. [PMID: 15367271 DOI: 10.1111/j.1439-0531.2004.00529.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Oestrogen receptor alpha (ERalpha), the main subtype in the uterus, is involved in the regulation of uterine growth/proliferation. A relationship between ERalpha and proliferative activity has been shown in the cyclic sow uterus, but to our knowledge, no study has been carried out on early pregnant sows. Therefore, by means of immunohistochemistry and use of mouse monoclonal antibodies to ERalpha and a proliferative marker, Ki-67, the localization of these proteins was investigated in the sow uterus during early pregnancy. Eighteen crossbred multiparous sows were artificially inseminated once at 20-15 h before expected ovulation. After artificial insemination (AI), they were slaughtered at five different times: at oestrus, 5-6 h after AI (n = 4), 20-25 h after ovulation (n =4), 70 h after ovulation (n = 4), on day 11 (the first day of standing oestrus = day 1, n = 3) and on day 19 (n = 3). Immediately after slaughter, uterine samples were collected at the mesometrial side of the uteri, fixed in 10% formaldehyde and embedded in paraffin. Immunohistochemistry was performed by using mouse monoclonal antibodies to ERalpha (C-311) and Ki-67 (MM1). All sows slaughtered after ovulation were pregnant. In general, positive immunostaining for ERalpha and Ki-67 was found in the nuclei. Variations in staining intensity and proportion of positive nuclei were observed in different uterine compartments and stages of early pregnancy. The highest level of ERalpha presence in the surface epithelium and myometrium was found at oestrus (5-6 h after AI), and low levels of ERalpha in these compartments were observed as early as 20-25 h after ovulation. In the glandular epithelia, presence of ERalpha was highest at 70 h after ovulation. The largest number of ERalpha-positive cells in the stroma was observed at oestrus and early after ovulation. Low proliferation was observed, and with no significant difference in tissue compartments except in the glandular epithelium. High proliferative activity in the glandular epithelium at 70 h after ovulation indicated involvement in preparation for secretory activity and growth during pregnancy establishment. Significant positive correlation was found between the number of ERalpha-positive cells in the stroma and Ki-67-positive cells in the surface epithelium. In conclusion, the present study showed differences in immunolocalization of ERalpha and the proliferative marker Ki-67 in different tissue compartments of the sow uterus at oestrus and early pregnancy. In some uterine compartments, the patterns of ERalpha and Ki-67 immunostaining seemed to be influenced by insemination and the presence of embryos, in addition to the effects of steroid hormones.
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Affiliation(s)
- S Sukjumlong
- Department of Anatomy and Physiology, Faculty of Veterinary Medicine and Animal Science, Swedish University of Agricultural Sciences (SLU) Uppsala, Sweden
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García P, Nieto A, Sánchez MA, Pizarro M, Flores JM. Expression of αv, α4, α5 and β3 integrin subunits, fibronectin and vitronectin in goat peri-implantation. Anim Reprod Sci 2004; 80:91-100. [PMID: 15036518 DOI: 10.1016/s0378-4320(03)00157-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2002] [Revised: 05/06/2003] [Accepted: 05/30/2003] [Indexed: 11/15/2022]
Abstract
Integrins are glycoprotein heterodimers located in the cell membranes that stimulate intercellular adhesion and act as extracellular matrix (ECM) protein receptors. Although integrins have been detected in the implantation sites of various species, little is known about their participation in ruminant non-invasive placentation. The objective of this study was the detection of alphav, alpha4, alpha5, beta1 and beta3 integrin subunits and of two of their ligands, fibronectin and vitronectin, to determine their participation in the caprine peri-implantation process. On Day 21 post-coitum (pc), endometrial epithelium and trophoblastic cells showed an intense alphav and beta3 integrin subunits expression and moderate staining for alpha4 and alpha5. On Day 23 pc, integrin expression decreased noticeably and only a weak staining of alpha4 and beta3 integrin subunits were observed. No beta1 integrin subunit expression was detected on either of the days studied. Fibronectin (FN) expression in trophectodermic and endometrial epithelium was weak or moderate on the days studied while vitronectin (VN) expression in the same tissues was moderate or strong on Day 21 pc but decreased on Day 23 pc. These results suggest that alphavbeta3 integrin, alpha4 and alpha5 subunits, VN and FN are expressed in caprine endometrium and blastocyst and may play a role in the cascade of the implantation process.
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Affiliation(s)
- P García
- Departamento de Patología Animal II, Facultad de Veterinaria, Universidad Complutense de Madrid, Ciudad Universitaria, E-28040 Madrid, Spain
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