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Implantation Site (implantation + site)
Selected AbstractsIs the Left Ventricular Lateral Wall the Best Lead Implantation Site for Cardiac Resynchronization Therapy?PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1p2 2003MAURIZIO GASPARINI GASPARINI, M., et al.: Is the Left Ventricular Lateral Wall the Best Lead Implantation Site for Cardiac Resynchronization Therapy?Short-term hemodynamic studies consistently report greater effects of cardiac resynchronization therapy (CRT) in patients stimulated from a LV lateral coronary sinus tributary (CST) compared to a septal site. The aim of the study was to compare the long-term efficacy of CRT when performed from different LV stimulation sites. From October 1999 to April 2002, 158 patients (mean age 65 years, mean LVEF 0.29, mean QRS width 174 ms) underwent successful CRT, from the anterior (A) CST in 21 patients, the anterolateral (AL) CST in 37 patients, the lateral (L) CST in 57 patients, the posterolateral (PL) CST in 40 patients, and the middle cardiac vein (MCV) CST in 3 patients. NYHA functional class, 6-minute walk test, and echocardiographic measurements were examined at baseline, and at 3, 6, and 12 months. Comparisons were made among all pacing sites or between lateral and septal sites by grouping AL + L + PL CST as lateral site (134 patients, 85%) and A + MC CST as septal site (24 patients, 15%). In patients stimulated from lateral sites, LVEF increased from 0.30 to 0.39(P < 0.0001), 6-minute walk test from 323 to 458 m(P < 0.0001), and the proportion of NYHA Class III,IV patients decreased from 82% to 10%(P < 0.0001). In patients stimulated from septal sites, LVEF increased from 0.28 to 0.41(P < 0.0001), 6-minute walk test from 314 to 494 m(P < 0.0001), and the proportion of NYHA Class III,IV patients decreased from 75% to 23%(P < 0.0001). A significant improvement in cardiac function and increase in exercise capacity were observed over time regardless of the LV stimulation sites, either considered singly or grouped as lateral versus septal sites. (PACE 2003; 26[Pt. II]:162,168) [source] Tissue reaction and biodegradation of implanted cross-linked high amylose starch in ratsJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 6 2002Cyril Désévaux Abstract The biocompatibility and degradation characteristics of cross-linked high amylose starch (Contramid®) were investigated in rats over 4 months. Contramid® pellets (3-mm diameter and thickness) obtained by direct compression, were implanted subcutaneously and intramuscularly. On sequential time points, macroscopic observations of implantation sites were performed and tissue samples were removed, fixed, and histologically evaluated. No macroscopic inflammatory reaction was observed with Contramid®. Upon histologic examination, inflammatory reaction produced by Contramid® was moderate and restricted to implantation sites. The sequence of inflammatory events with Contramid® was similar regardless of implantation site. Degradation of Contramid® pellets was characterized by fragmentation with formation of fibrovascular septa and phagocytosis by macrophages. Finally Contramid® was mostly absorbed by the end of the 4-month period and substituted by adipocytes. It has been demonstrated that Contramid® is a biocompatible and absorbable material. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res (Appl Biomater) 63: 772,779, 2002 [source] Failure of xenoimplantation using porcine synovium-derived stem cell-based cartilage tissue constructs for the repair of rabbit osteochondral defectsJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 8 2010Ming Pei Abstract The use of xenogeneic tissues offers many advantages with respect to availability, quality control, and timing of tissue harvest. Our previous study indicated that implantation of premature tissue constructs from allogeneic synovium-derived stem cells (SDSCs) facilitated cartilage tissue regeneration. The present study investigated the feasibility of xenoimplantation of SDSC-based premature tissue constructs for the repair of osteochondral defects. Porcine SDSCs were mixed with fibrin gel, seeded in polyglycolic acid (PGA) scaffolds, and cultured in a rotating bioreactor system supplemented for 1 month with growth factor cocktails. The engineered porcine premature tissues were implanted to repair surgically induced osteochondral defects in the medial femoral condyles of 12 rabbits. Three weeks after surgery, the xenoimplantation group exhibited a smooth, whitish surface while the untreated control remained empty. Surprisingly, 6 months after surgery, the xenoimplantation group displayed some tissue loss while the untreated control group was overgrown with fibrocartilage tissue. In the xenoimplantation group, chronic inflammation was observed in synovial tissue where porcine major histocompatibility complex (MHC) class II antigen positively stained in the engulfed foreign bodies. In addition, porcine source cells also migrated from the implantation site and may have been responsible for the observed loss of glycosaminoglycans (GAGs) underneath surrounding articular cartilage. The histological score was much worse in the xenoimplanted group than in the untreated control. Our study suggested that SDSC-based xenogeneic tissue constructs might cause delayed immune rejection. Xenotransplantation may not be an appropriate approach to repair osteochondral defects. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1064,1070, 2010 [source] An overview on the development of a bio-artificial pancreas as a treatment of insulin-dependent diabetes mellitusMEDICINAL RESEARCH REVIEWS, Issue 2 2006Ana Isabel Silva Abstract This paper presents the concept and most of the research undertaken all over the world for the development of a bio-artificial pancreas (BAP) device over the last 30 years. The devices studied, meant to mimic the insulin secretion of the natural organ, were diverse and have been reviewed. Allogeneic or xenogeneic cells or cell clusters have been separated from the host's immune system by synthetic biocompatible semipermeable membranes to prevent the need, of the host, for immune-suppressing regimens. The biocompatible polymer used as a barrier and its intrinsic characteristics, the cell immobilization or suspension media, the existence or not of co-immobilized molecules or cells, the number of devices used and the implantation site, were addressed. © 2005 Wiley Periodicals, Inc. Med Res Rev [source] Differential expression of transcriptional repressor snail gene at implantation site in mouse uterusMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 2 2006Xing-Hong Ma Abstract The snail superfamily of zinc-finger transcription factors is involved in pronounced cell movements during both embryonic development and tumor progression. This study was to examine snail expression in mouse uterus during early pregnancy and its regulation under pseudopregnancy, delayed implantation, steroid hormone treatment, and artificial decidualization by in situ hybridization and immunohistochemistry. There was a low level of snail mRNA signal and immunostaining in mouse uteri on day 1,4 of pregnancy. When embryo implanted on day 5, both snail mRNA signal and immunostaining were strongly detected in the subluminal stroma immediately surrounding the implanting blastocyst, but not detected in the inter-implantation sites. Under delayed implantation, there was no detectable snail expression. After delayed implantation was terminated by estrogen treatment and embryo implanted, there was a strong level of snail mRNA and immunostaining in the subluminal stroma surrounding the implanting blastocyst, which was similar to that on day 5 of pregnancy. Furthermore, there was no detectable snail expression in mouse uterus on day 5 of pseudopregnancy. From day 6,8 of pregnancy, both snail mRNA signal and immunostaining were detected in the decidua. Our data suggest that snail may play an important role during mouse embryo implantation. Mol. Reprod. Dev. © 2005 Wiley-Liss, Inc. [source] Decidualization and implantation: Embryo-uterine bioinformatics at workMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 2 2001Abraham L. Kierszenbaum The implantation of the blastocyst into a nurturing endometrium involves two overlapping steps: 1. The blastocyst-endometrial luminal epithelial attachment. 2. The decidualization of the endometrial stroma. An intriguing question is how does the blastocyst identify the uterine implantation site. Current research is focused on hypothetical soluble signaling molecules released by the blastocyst for conditioning a discrete uterine luminal epithelial domain for implantation. A still unresolved issue is the functional significance of receptor autophosphorylation following binding of uterine epithelial cell-derived heparin-binding epidermal growth factor-like growth factor to the epidermal growth factor receptor on trophoectodermic cell surfaces. With recent results hinting at the role of signaling proteins associated with the bone morphogenetic protein, fibroblast growth factor, WNT and hedgehog families to enable embryo implantation, the dynamics of uterine-embryo interaction becomes linked to fundamental cellular pathways of growth, differentiation and apoptosis. Mol. Reprod. Dev. 59:123,125, 2001. © 2001 Wiley-Liss, Inc. [source] Thalamic deep brain stimulation: Effects on the nontarget limbsMOVEMENT DISORDERS, Issue 6 2001William Ondo MD Abstract Unilateral thalamic ventral intermediate (VIM) deep brain stimulation (DBS) is now accepted as an effective treatment for essential tremor (ET) and tremor related to Parkinson's disease (PD). The effects of unilateral placement on the side ipsilateral to the surgical site have not been carefully evaluated. To systematically assess the effects ipsilateral to the surgical side and to determine the effects of device inactivation on the baseline tremor, we evaluated tremor in 73 patients approximately 3 months after their unilateral thalamic placement. Assessment included blinded and unblinded ratings using the Unified Parkinson's Disease Rating Scale for PD patients and a modified Tremor Rating Scale in ET patients. All measures of tremor contralateral to the implantation site improved significantly and robustly in both PD and ET. Implantation did not worsen tremor by any measure on the ipsilateral side. There was mild ipsilateral improvement as measured by lower observed tremor scores in ET (6.0 ± 1.8 to 5.0 ± 1.9, P < 0.005), but not PD. There was no rebound augmentation of tremor in either hand after the devices were deactivated in either group. We conclude that VIM DBS may mildly improve ipsilateral ET, and that concerns about meaningful ipsilateral tremor augmentation after device deactivation are not warranted. © 2001 Movement Disorder Society. [source] Evaluation of biocompatibility of a pectin/polyvinyl alcohol composite hydrogel as a new nucleus materialORTHOPAEDIC SURGERY, Issue 3 2009Nv-zhao Yao MD Objective:, To evaluate the biocompatibility of a new kind of prosthetic nucleus: a pectin/polyvinyl alcohol composite (CoPP) hydrogel. Methods:, According to Chinese national standard GB/-T16886 documents, the toxicity of the CoPP prosthetic nucleus material was examined by cytotoxicity, sensitization, Ames, mice marrow micronucleus, chromosome aberration test of mammalian cell and implantation tests. Results:, Cell growth was similar in the CoPP culture and control groups. No significant difference was found between the CoPP culture and control groups at each time point (P > 0.05). The cell proliferation rate was greater than 100%. In accordance with the relationship between cytotoxicity to proliferation rate, it was confirmed that the cytotoxicity of CoPP was 0 grade. Mice had no allergic reaction when injected with an extract of CoPP. A reverse mutation test with Salmonella typhimurium showed that no significant effect on the number of histidine revertants of TA97, TA98, TA100 and TA102 strains after CoPP was added. The micronucleus rate in bone marrow cells was less than 5%; there was no significant difference compared with the negative control group (P > 0.05). The rate of chromosome aberration was less than 5%; no significant difference was found between the CoPP culture and the control groups. All experimental animal wounds achieved primary healing without exudation, infection or sinus formation. On macroscopic observation, no abscess or hematoma formed at the implantation site. Conclusion:, The CoPP prosthetic nucleus has good biocompatibility and can potentially be used as an implant material. [source] Inferior Vena Cava Approach to Permanent Pacemaker ImplantationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 6 2007MARTIN BRUECK M.D. A 89-year-old woman required permanent pacemaker implantation because of symptomatic bradyarrhythmia with multiple falls and repeated fractures. Because of the obstruction of the thoracic veins and infection of both groins, an alternative approach via directly punctured inferior vena cava was performed. At follow-up, the patient remained well with an excellent symptomatic response to pacing. The method seems simple to perform and is an alternative when the usual pectoral implantation site is inaccessible. [source] Tubal ectopic pregnancy associated with an adenomatoid tumorPATHOLOGY INTERNATIONAL, Issue 3 2001Teruhiko Inoue We present a case of coexistence of an ectopic pregnancy and an adenomatoid tumor in the same fallopian tube. The adenomatoid tumor is the most common benign neoplasm of the fallopian tube, and the vast majority of ectopic pregnancies occur in the fallopian tube. However, coexistence of these two conditions is extremely rare, and there has been only one previously reported case in the English literature. In the present case, the placental tissue, consisting of chorionic villi and decidua, was present in the ampulla, and the adenomatoid tumor was found in the myosalpinx, just proximal to the implantation site, replacing a large part of the myosalpinx. The close spatial relationship of these two lesions suggests that an adenomatoid tumor could have interfered with transportation of the fertilized ovum through the tube, possibly via impaired contractile activity of the myosalpinx, and consequently caused the ectopic tubal pregnancy. [source] Experimental Setup to Evaluate the Performance of Percutaneous Pulmonary Valved Stent in Different Outflow Tract MorphologiesARTIFICIAL ORGANS, Issue 1 2009Riccardo Vismara Abstract Percutaneous pulmonary valve implantation is a potential treatment for right ventricular outflow tract (RVOT) dysfunction. However, RVOT implantation site varies among subjects and the success of the procedure depends on RVOT morphology selection. The aim of this study was to use in vitro testing to establish percutaneous valve competency in different previously defined RVOT morphologies. Five simplified RVOT geometries (stenotic, enlarged, straight, convergent, and divergent) were manufactured by silicone dipping. A mock bench was developed to test the percutaneous valve in the five different RVOTs. The bench consists of a volumetric pulsatile pump and of a hydraulic afterload. The pump is made of a piston driven by a low inertia programmable motor. The hydraulic afterload mimics the pulmonary input impedance and its design is based on a three element model of the pulmonary circulation. The mock bench can replicate different physiological and pathological hemodynamic conditions of the pulmonary circulation. The mock bench is here used to test the five RVOTs under physiological-like conditions: stroke volume range 40,70 mL, frequency range 60,80 bpm. The valved stent was implanted into the five different RVOT geometries. Pressures upstream and downstream of the valved stent were monitored. Flow rates were measured with and without the valved stent in the five mock RVOTs, and regurgitant fraction compared between the different valved stent RVOTs. The percutaneous valved stent drastically reduced regurgitant flow if compared with the RVOT without the valve. RVOT geometry did not significantly influence the flow rate curves. Mean regurgitant fractions varied from 5% in the stenotic RVOT to 7.3% in the straight RVOT, highlighting the influence of the RVOT geometry on valve competency. The mock bench presented in this study showed the ability to investigate the influence of RVOT geometry on the competence of valved stent used for percutaneous pulmonary valve treatment. [source] High Order Aberrations of the eye implanted the Verisyse® iris-claw intraocular lensACTA OPHTHALMOLOGICA, Issue 2007JJ GICQUEL Purpose: To investigate the influence of the secondary implantation site of the Verisyse® iris-claw intraocular lens (IOL) on high order aberrations (HOAs) using wavefront analysis in aphakic patients. Methods: Twenty aphakic patients (20 eyes) who had complicated phacoemulsification, leaving no capsular support, but good iris support and clear unwounded cornea implantated with the aphakic Verisyse®(AMO) intraocular lens site either implanted retropupilarely or over the iris. Wavefront aberrations were measured using the IRX3 Hartmann-Shack aberrometer at 4 mm pupil aperture diameter. Results: Nine patients were implanted in the anterior chamber versus 11 who had the IOL clipped behind the iris. Best corrected visual acuity was significantly higher and HOAs were significantly lower in the retropupilarely implanted group. Conclusions: In addition to being atraumatic, the Verisyse® intraocular lens implanted behind the iris may restore vision in the absence of capsular support in a more physiological way than when fixated over the iris. [source] Orthodontic loading of titanium miniplates in dogs: microradiographic and histological evaluationCLINICAL ORAL IMPLANTS RESEARCH, Issue 10 2008M. A. Cornelis Abstract Objectives: The objectives of this animal study were to evaluate if orthodontic loading has an impact on osseointegration of screws supporting miniplates, and to describe the histological components of the bone,screw interface. Materials and methods: Eighty orthodontic miniplates were placed in the jaws of 10 dogs. After 2 weeks, a 125 g force was applied between the miniplates of one upper quadrant of each dog and between those of the controlateral lower quadrant. The others, nonloaded miniplates, were considered as controls. Five dogs were sacrificed 7 weeks after implantation and the remaining five dogs after 29 weeks [Short Term (ST) and Long Term (LT) groups, respectively]. Fluorochromes were injected at implantation and at sacrifice. Jaw quadrants were dissected, embedded, cut into undecalcified transverse sections through the screws and finally submitted to microradiographic analysis to allow assessment of bone,implant contact (BIC) and bone volume/total volume (BV/TV). The sections were observed under UV light and stained in order to examine them under ordinary light. Results: Osseointegration occurred around 90/160 screws and consisted mainly in limited repair and remodelling processes of lamellar bone, without inflammation. Wide variations were observed in BIC and BV/TV, but without any significant difference, neither between the loaded and the nonloaded screws, nor according to the direction of load, whereas they were significantly higher in the LT than in the ST group. Nonosseointegrated screws were surrounded by fibrous tissue. Osteoblastic activity, when present in front of these screws, was not sufficient to achieve stability. Conclusions: Osseointegration underlying orthodontic anchorage was not affected by loading. BIC increased with time and varied according to implantation site. Particularly the tight-fitting screw insertion appeared crucial in determining the appropriate bone healing response. [source] Eph,ephrin A system regulates murine blastocyst attachment and spreadingDEVELOPMENTAL DYNAMICS, Issue 12 2006Haruko Fujii Abstract Although numerous adhesion molecules are expressed on mammalian endometrial epithelial cells, there have not been any studies of a mechanism to prevent premature attachment of the embryo. In this study, we examined the possible involvement of Eph,ephrin interaction, which can induce repulsive forces. In mice, Eph A1, A2, and A4 were expressed on endometrial epithelial cells and ephrin A1,4 on blastocysts. Reverse transcriptase-polymerase chain reaction showed that mRNA expression of ephrin A1,4 on embryos transiently decreased around the implantation period. Immunohistochemistry demonstrated that the expression of Eph A1 on endometrial epithelial cells and ephrin A1 and A3 expression on embryos decreased at implantation sites. Recombinant Eph A1 reacted with cell the surface of ephrin A-bearing trophectoderm cells. Attachment assays using Eph A1-coated dishes showed that blastocyst attachment was reversibly inhibited by Eph A1. These findings suggest an important role of the Eph,ephrin A system in regulating the initial embryo,maternal contact during the cross-talk period that precedes embryo implantation. Developmental Dynamics 235:3250,3258, 2006. © 2006 Wiley-Liss, Inc. [source] Conditional gene recombination by adenovirus-driven Cre in the mouse uterusGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 2 2006Haibin Wang Abstract Cre-mediated conditional gene targeting has been shown to be successful in many cell and tissue types. However, gene recombination in the uterus with heterogeneous cell types by Cre activation is not yet well established. Using recombinant adenoviruses expressing a functional Cre (ADV-Cre) and ROSA26 reporter mice, we show here that ADV-Cre infused intraluminally in a small volume (10 ,l) conditionally excises the loxP site, resulting in lacZ expression in uterine luminal epithelial cells without significantly affecting pregnancy. In contrast, a similar intraluminal infusion of ADV-Cre in a larger volume (50 ,l) damages the normal architecture and integrity of the luminal epithelium, inducing gene recombination in the underneath stromal cells, with disruption of pregnancy. Further, decidualizing stromal cells at the implantation sites can be targeted by ADV-Cre after intravenous administration on days 5,6. This route of administration also elicits Cre activity in other tissues, including the liver, spleen, ovary, and, more remarkably, in the adrenal cortex. These findings demonstrate the feasibility of achieving conditional expression or deletion of specific genes in uterine cells at desired times and physiological states. genesis 44:51,56, 2006. © 2006 Wiley-Liss, Inc. [source] Tissue reaction and biodegradation of implanted cross-linked high amylose starch in ratsJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 6 2002Cyril Désévaux Abstract The biocompatibility and degradation characteristics of cross-linked high amylose starch (Contramid®) were investigated in rats over 4 months. Contramid® pellets (3-mm diameter and thickness) obtained by direct compression, were implanted subcutaneously and intramuscularly. On sequential time points, macroscopic observations of implantation sites were performed and tissue samples were removed, fixed, and histologically evaluated. No macroscopic inflammatory reaction was observed with Contramid®. Upon histologic examination, inflammatory reaction produced by Contramid® was moderate and restricted to implantation sites. The sequence of inflammatory events with Contramid® was similar regardless of implantation site. Degradation of Contramid® pellets was characterized by fragmentation with formation of fibrovascular septa and phagocytosis by macrophages. Finally Contramid® was mostly absorbed by the end of the 4-month period and substituted by adipocytes. It has been demonstrated that Contramid® is a biocompatible and absorbable material. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res (Appl Biomater) 63: 772,779, 2002 [source] Relevance of Osteoinductive Biomaterials in Critical-Sized Orthotopic DefectJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 5 2006Pamela Habibovic Abstract Several publications have shown the phenomenon of osteoinduction by biomaterials to be real. However, whether the ability of a biomaterial to initiate bone formation in ectopic implantation sites improves the performance of such osteoinductive biomaterial in clinically relevant orthotopic sites remains unclear. No studies have been published in which osteoinductive potential of a biomaterial is directly related to its performance orthotopically. In this study, we compared osteoinductive and nonosteoinductive biphasic calcium,phosphate (BCP) ceramics ectopically and in a clinically relevant critical-sized orthotopic defect in goats. The two materials, BCP1150 and BCP1300, had similar chemical compositions, crystallinities, and macrostructures, but their microstructures differed significantly. BCP1150, sintered at a lower temperature, had a large amount of micropores, small average crystal size, and hence a high specific surface area. In contrast, BCP1300, with few micropores, had a significantly lower specific surface area as compared to BCP1150. Twelve-week intramuscular implantation in goats (n,=,10) showed that bone was induced in all BCP1150 implants, while no signs of bone formation were found in any of the BCP1300 implants. After 12 weeks of implantation in a bilateral critical-sized iliac wing defect in the same goats, BCP1150 showed significantly more bone than BCP1300. In addition, the analysis of fluorochrome markers, which were administered to the animals 4, 6, and 8 weeks after implantation to follow the bone growth dynamics, showed an earlier start of bone formation in BCP1150 as compared to BCP1300. Significantly better performance of an osteoinductive ceramic in a critical-sized orthotopic defect in a large animal model in comparison to a nonosteoinductive ceramic suggests osteoinduction to be clinically relevant. Further improvement of material osteoinductive properties is thus a significant step forward in the search for alternatives for autologous bone graft. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [source] AB-polymer Networks with Cooligoester and Poly(n -butyl acrylate) Segments as a Multifunctional Matrix for Controlled Drug ReleaseMACROMOLECULAR BIOSCIENCE, Issue 9 2010Christian Wischke Abstract Semi-crystalline AB-copolymer networks from oligo[(, -caprolactone)- co -glycolide]dimethacrylates and n -butylacrylate have recently been shown to exhibit a shape-memory functionality, which may be used for self-deploying and anchoring of implants. In this study, a family of such materials differing in their molar glycolide contents ,G was investigated to determine structure,property functional relationships of unloaded and drug loaded specimens. Drug loading and release were evaluated, as well as their degradation behavior in vitro and in vivo. Higher ,G resulted in higher loading levels by swelling and a faster release of ethacridine lactate, lower melting temperature of polymer crystallites, and a decrease in shape fixity ratio of the programmed temporary shape. For unloaded networks, the material behavior in vivo was independent of the mechanical load associated with different implantation sites and agreed well with data from in vitro degradation studies. Thus, AB networks could be used as novel matrices for biofunctional implants, e.g., for urogenital applications, which can self-anchor in vivo and provide mechanical support, release drugs, and finally degrade in the body to excretable fragments. [source] Differential expression and activation of Stat3 during mouse embryo implantation and decidualizationMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 1 2004Chun-Bo Teng Abstract Signal transducer and activator of transcription (STATs) can be activated by many cytokines and growth factors. Stat3, a member of STAT family, is essential for embryonic development. Stat3 is specifically activated during mouse embryo implantation. This study was to investigate the expression, activation, and regulation of Stat3 in mouse uterus during early pregnancy, pseudopregnancy, delayed implantation, artificial decidualization, and hormonal treatments using in situ hybridization and immunohistochemistry. There was a strong level of Stat3 phosphorylation in the luminal epithelium only at the midnight of day 4 pregnancy, which coincides with attachment reaction between the blastocyst and luminal epithelium. However, there was no detectable Stat3 phosphorylation at the corresponding period during pseudopregnancy. On day 5 of pregnancy, Stat3 phosphorylation was strongly observed in the luminal epithelium and the stroma surrounding the implanting blastocyst at implantation sites, but not at the inter-implantation sites. Stat3 phosphorylation was also not detected on day 5 of pseudopregnancy. Stat3 phosphorylation was at a high level in the decidual cells on days 6,8 of pregnancy. Under artificial decidualization, Stat3 was also phosphorylated in the decidual cells. In the ovariectomized mice, there was no Stat3 expression and activation in the uterus. Progesterone had no obvious effects. However, Stat3 mRNA expression and phosphorylation were significantly stimulated by estrogen treatment. Our data suggest that Stat3 phosphorylation may be important for mouse embryo implantation and decidualization, and may also be regulated by maternal estrogen. Mol. Reprod. Dev. 69: 1,10, 2004. © Wiley-Liss, Inc. [source] Peroxisome proliferator-activated receptor delta expression and regulation in mouse uterus during embryo implantation and decidualizationMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 3 2003Nai-Zheng Ding Abstract The aim of this study was to examine the expression and regulation of peroxisome proliferator-activated receptor (PPAR) PPAR, gene in mouse uterus during early pregnancy by in situ hybridization and immunohistochemistry. PPAR, expression under pseudopregnancy, delayed implantation, hormonal treatment, and artificial decidualization was also investigated. There was a very low level of PPAR, expression on days 1,4 of pregnancy. On day 5 when embryo implanted, PPAR, expression was exclusively observed in the subluminal stroma surrounding the implanting blastocyst. No corresponding signals were seen in the uterus on day 5 of pregnancy. There was no detectable PPAR, signal under delayed implantation. Once delayed implantation was terminated by estrogen treatment and embryo implanted, a strong level of PPAR, expression was induced in the subluminal stroma surrounding the implanting blastocyst. Estrogen treatment induced a moderate level of PPAR, expression in the glandular epithelium, while progesterone treatment had no effects in the ovariectomized mice. A strong level of PPAR, expression was seen in the decidua on days 6,8 of pregnancy. PPAR, expression was also induced under artificial decidualization. These data suggest that PPAR, expression at implantation sites require the presence of an active blastocyst and may play an essential role for blastocyst implantation. Mol. Reprod. Dev. 66: 218,224, 2003. © 2003 Wiley-Liss, Inc. [source] Expression of MHC-I and -II in Uterine Tissue from Early Pregnant BitchesREPRODUCTION IN DOMESTIC ANIMALS, Issue 2009S Schäfer-Somi Contents The aim of the study was to investigate the expression of major histocompatibility complex (MHC)-I and -II in uterine tissues from pregnant and non-pregnant bitches, taken at different time periods after mating. The pregnant bitches were ovariohysterectomized during the pre-implantation (group 1, n = 4), implantation (group 2, n = 7) and placentation stage (group 3, n = 7). Non-pregnant animals in diestrus served as controls (group 4, n = 7). The expression of MHC- I and -II in salpinx, apex, middle horn, corpus uteri and at implantation sites was investigated by immunohistochemistry as well as qualitative and quantitative RT-PCR; MHC-I mRNA was detected in all tissues and with quantitative RT-PCR, and no significant changes were detected until placentation. Immunohistologically, at the apex and corpus site, the average number of MHC-II positive cells increased from the pre-implantation to the post-implantation stage (apex: 1.54 ± 1.21 to 3.82 ± 2.93; corpus: 1.62 ± 1.9 to 5.04 ± 4.95; p < 0.05). The greatest numbers of MHC-II positive cells were observed at placentation sites (6.64 ± 5.9). In parallel, a marked increase in the relative mRNA expression of MHC-II in uterine tissues was assessed from the pre-implantation to the placentation stage (relative to Glycerinaldehyd-3-phosphate-Dehydrogenase (GAPDH): 6.9 ± 9.5, 8.4 ± 5.8, p > 0.05). Immunohistologically, in the salpinx, significantly greater numbers of MHC-II positive cells were found in the tissues of pregnant animals than in the control group (p < 0.05). It is proposed that the increase in MHC-II is pregnancy-related, even though the impact on maintenance of canine pregnancy is still unclear. [source] ORIGINAL ARTICLE: How Should Data on Murine Spontaneous Abortion Rates be Expressed and Analyzed?AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 3 2008David A. Clark Problem, Spontaneous abortions in the CBA × DBA/2 model are normally reported as number of resorptions/total number of implantations (R/T), pooling data from individual mice. The significance of differences between groups has been determined using non-parametric statistics (e.g. chi-square or Fisher's Exact test) based on a priori predictions. Recently, it has been argued that medians with box plots should replace the accepted standard, but this deprives readers of data needed to verify P -values, and leads to inferences incompatible with biological and statistical reality. Method of study, Raw data on 173 individual CBA × DBA/2 matings were analyzed by median and mean, along with R/T data from 18 independent experiments containing 5,10 mice per group. Raw data from 19 CBA × BALB/c matings were similarly analyzed. Results, Individual CBA × DBA/2 mouse resorption rates showed a non-Gaussian distribution, but the mean and median differed by <0.5%. Resorption data from 6 and 12 independent pools of mice were normally distributed. Only the mean enabled a between-group P -value calculation. CBA × BALB/c matings gave a median of 0 and mean of 5.1%; the data were not normally distributed, but that was because of a bimodal distribution. One group of mice had 0 abortions, and the second a mean of 13.9% abortions, and the data from the latter group were normally distributed. Conclusion, Although it is possible to compare individual mice, and even individual implantation sites, in resorption (abortion) studies, as the relevant question is the significance of differences between treatment groups of mice, and reproducibility, the established classical method of reporting R/T should continue to be provided. In CBA × BALB/c matings, where abortion rates are low, using the median is misleading and may obscure the existence of two distinct populations. [source] | ||||||||||||||||