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41.
This study focuses on recent improvement in epithelial monolayer cultures originating from whole extirpated Botryllus schlosseri (Urochordata) buds. Buds (n = 2,000) were taken at different (A to D) blastogenic stages. We tested the suitability of 35 combinations of various substrates and media on attachment, cell spread, epithelial growth frequencies and on monolayer lifespans. Under favorable conditions, cultured buds at blastogenic stages B to D (but not stage A) started to attach to the substrates following a 3-day transient period that leads to formation of spheres and attached monolayers. Substrate type is important for the attachment and the development of monolayers. Under various culture conditions, some of stages B and C buds develop (3–20 days) one or more large (1 mm diameter) spheres. Stage D buds develop monolayers (up to 20% of buds) without going through a sphere phase. Neither spheres nor attached monolayers of epithelium were observed in stage A bud cultures. Spheres grew at a rate of 60 m in diameter per day using specific medium types and did not attach unless the appropriate substrate was present. When attached, epithelial monolayers expanded at a rate of 200 m in diameter per day, for 3–15 days, and subsequently detached and died. Sixteen types of media were tested. Medium and substrate combinations were found to determine epithelial lifespan. These results revealed significant improvements in the culture of epithelial monolayers from Botryllus palleal buds. However, an early senescence of the developed epithelial sheets (up to two weeks from onset of appearance) may indicate an internal ageing clock that should be taken into consideration in future approaches. 相似文献
42.
Tsiperson V Goldshmidt O Ilan N Shoshany G Vlodavsky I Veitsman E Baruch Y 《Tissue engineering. Part A》2008,14(3):449-458
Hepatocyte transplantation is an emerging approach for the treatment of liver diseases. However, broad clinical application of this method has been limited by restricted source of cells and low efficiency of cell integration within the recipient liver. Heparanase cleaves heparan sulfate proteoglycans in the extracellular matrix and basement membrane, activity that affects cellular invasion associated with cancer metastasis and inflammation. This activity has a multifunctional effect on cell-cell interaction, cell adhesion, and angiogenesis. All these factors are important for successful integration of transplanted hepatocytes. Male donor hepatocytes pretreated with heparanase or untreated were transplanted into recipient female rat spleen following partial hepatectomy. Engraftment efficacy was evaluated by PCR for Y chromosome, histology and PCNA, and heparanase immunohistochemistry. In addition, proliferative activity of hepatocytes in vitro was determined by bromodeoxyuridine immunostaining. The number of heparanase-treated cells detected in the recipient liver was significantly increased three- to fivefold within 24-48 h posttransplantation and twofold at 14 days compared with untreated cells. The transplanted hepatocytes treated with heparanase were clearly seen inside portal vein radicles as cell aggregates up to 72 h posttransplantation. The number of portal radicles filled with heparanase-treated hepatocytes was increased compared to control early after transplantation. Heparanase treatment enhanced hepatocyte and sinusoidal endothelial cell proliferation in the liver, and hepatocyte proliferation within the spleen tissue. Preliminary in vitro studies with isolated hepatocytes treated with heparanase showed increased proliferative activity within 24-48 h of cell culture. These results suggest that preincubation of hepatocytes with heparanase increases the presence of hepatocytes within the recipient liver early following cell transplantation and stimulates both hepatocyte and sinusoidal endothelial cell proliferation. 相似文献
43.
Chander Sadasivan David J. Fiorella Henry H. Woo Baruch B. Lieber 《Annals of biomedical engineering》2013,41(7):1347-1365
Many factors that are either blood-, wall-, or hemodynamics-borne have been associated with the initiation, growth, and rupture of intracranial aneurysms. The distribution of cerebral aneurysms around the bifurcations of the circle of Willis has provided the impetus for numerous studies trying to link hemodynamic factors (flow impingement, pressure, and/or wall shear stress) to aneurysm pathophysiology. The focus of this review is to provide a broad overview of such hemodynamic associations as well as the subsumed aspects of vascular anatomy and wall structure. Hemodynamic factors seem to be correlated to the distribution of aneurysms on the intracranial arterial tree and complex, slow flow patterns seem to be associated with aneurysm growth and rupture. However, both the prevalence of aneurysms in the general population and the incidence of ruptures in the aneurysm population are extremely low. This suggests that hemodynamic factors and purely mechanical explanations by themselves may serve as necessary, but never as necessary and sufficient conditions of this disease’s causation. The ultimate cause is not yet known, but it is likely an additive or multiplicative effect of a handful of biochemical and biomechanical factors. 相似文献
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46.
Y Menashe G Ben Baruch O Rabinovitch Y Shalev M B Katzenlson E Shalev 《Prenatal diagnosis》1989,9(11):805-808
Prenatal real-time ultrasonographic diagnosis of exophthalmus is presented. Diagnosis was made at the 35th week of gestation in a fetus of a patient affected with Crouzon syndrome (craniofacial dysotosis). Recognition of exophthalmus as a part of Crouzon syndrome and the easy visualization of the eye balls and palpebrae in the third trimester made the diagnosis possible. 相似文献
47.
The umbilical venous hematocrit at birth (Hct 1) and the peripheral venous hematocrit at 2 h of life (Hct 2) were determined in 78 healthy full-term and 14 healthy preterm newborn infants. Hct 1 was 51.6 +/- 4.1% in full-term infants and 50.8 +/- 4% in preterm infants. Hct 2 was 60.9 +/- 2 and 58.6 +/- 6.1% in full-term and preterm infants, respectively. Significant differences between Hct 1 and Hct 2 were found in both groups of infants (p less than 0.01). The blood viscosity increased significantly in both groups from birth to 2 h of life. Neonatal polycythemia (Hct higher than 70% at 2 h of life) was detected in only 3 full-term infants (3.8%). They received partial exchange transfusion. There was a positive linear correlation of Hct 1 with Hct 2 in full-term newborns (r = 0.71, p less than 0.001) and preterm infants (r = 0.57, p less than 0.02). No infants with Hct 1 equal to or below 50% had Hct 2 higher than 65%. None with Hct 1 between 51 and 54% had Hct 2 higher than 70%. Neither Hct 1 nor Hct 2 correlated with birth weight, gestational age, total blood solutes, or reticulocyte counts at birth in either group. An inverse linear correlation was found between blood pH at birth and Hct 2 in preterm newborn infants (r = 0.66, p less than 0.02). 相似文献
48.
Silverberg DS Wexler D Blum M Tchebiner J Sheps D Keren G Schwartz D Baruch R Yachnin T Shaked M Zubkov A Steinbruch S Iaina A 《Clinical nephrology》2002,58(Z1):S37-S45
Both Congestive Heart Failure (CHF) and Chronic Renal Failure (CRF) are increasing steadily in the community. We propose that there is a vicious circle established whereby CHF and CRF both cause anemia and the anemia then worsens both the CHF and CRF causing more anemia and so on. We call this the Cardio Renal Anemia (CRA) syndrome. By the combination of active treatment of the CHF and control of the anemia with subcutaneous erythropoietin and intravenous iron, the progression of both the CHF and the CRF can be slowed or stopped in most cases, the quality of life improved and the need for recurrent hospitalization reduced. This will involve cooperation between internists, cardiologists, and nephrologists to allow early and maximal therapy of both the CHF and the anemia. 相似文献
49.
Spivak B Shabash E Sheitman B Weizman A Mester R 《The Journal of clinical psychiatry》2003,64(7):755-760
BACKGROUND: The risk of suicide for schizophrenia patients is 20 to 50 times higher than that for the general population. Long-term treatment with clozapine, an atypical antipsychotic, has been shown to reduce the rate of suicide by 80% to 85%. The goal of the present study was to examine whether clozapine's effect on the reduction of suicidal behavior in chronic schizophrenic patients could be due to a reduction in impulsive-aggressive behavior. METHOD: 44 patients with chronic DSM-IV schizophrenia were treated with clozapine or haloperidol decanoate in an open prospective 6-month trial. Changes in measures of suicidality, impulsiveness, aggression, depressed mood, and positive and negative symptoms were assessed at baseline and at 6 months. RESULTS: The clozapine-treated group (N = 18) had a significantly greater reduction on all outcome measures compared with the haloperidol decanoate-treated group (N = 26). Only in the clozapine-treated group did the reduction in measures of suicidality correlate significantly with a reduction in impulsiveness and aggression. The reductions in suicidality and impulsive aggression were not significantly correlated with reductions in depressed mood or positive and negative symptom scores in either group. CONCLUSION: These data suggest that the reduction in suicidality following long-term clozapine treatment may be related to a reduction in impulsiveness and aggression. 相似文献
50.