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1.
Summary.  Previously we demonstrated that domain 5 (D5) of high-molecular-weight kininogen (HK) inhibits neovascularization in the chicken chorioallantoic membrane (CAM) assay and further found that kallikrein cleaved HK (HKa) inhibited FGF2-and VEGF-induced neovascularization, and thus was antiangiogenic. In this study, we sought to demonstrate whether uncleaved HK stimulates neovascularization and thus is proangiogenic. The chick chorioallantoic membrane was used as an in ovo assay of angiogenesis. Low-molecular-weight kininogen stimulates angiogenesis, indicating that D5 is not involved. Bradykinin stimulates neovascularization equally to HK and LK and is likely to be responsible for the effect of HK. A murine monoclonal antibody to HK (C11C1) also recognizes a similar component in chicken plasma as detected by surface plasmon resonance. Angiogenesis induced by FGF2 and VEGF is inhibited by this monoclonal antibody and is a more potent inhibitor of neovascularization induced by VEGF than an integrin αvβ3 antibody (LM 609). Our postulate that C11C1 inhibits the stimulation of angiogenesis by HK was confirmed when either C11C1 or D5 completely inhibited angiogenesis in the CAM induced by HK. Growth of human fibrosarcoma (HT-1080) on the CAM was inhibited by GST-D5 and C11C1. These results indicate HK is proangiogenic probably by releasing bradykinin and that a monoclonal antibody directed to HK could serve as an antiangiogenic agent with a potential for inhibiting tumor angiogenesis and other angiogenesis-mediated disorders.  相似文献   
2.
The possible immunoregulatory role of the tonsils was studied by determining immunoglobulins IgG, A, M, E and factors C'3, C'4 and PFB of the complement system before and after tonsillectomy. The synthesis in vitro of IgG and IgM by lymphocytes stimulated with pokeweed mitogen was also measured. There were statistically significant differences between pre and post-operative levels of serum IgG, IgA and IgM, which decreased after surgery. Practically no change in the mean values of IgE and no significant differences in the levels of serum C'3, C'4, and PFB, were found. The in-vitro synthesis of both immunoglobulins (IgG, IgM) by lymphocytes increased significantly after tonsillectomy. Our results suggest that not only does tonsillectomy have no counterproductive effect on the immune system, but that, on the contrary, it seems to improve the immune response, since it appears to unblock the suppression to which the immune system was subject.  相似文献   
3.
Enhanced Recovery After Surgery (ERAS) constitutes the application of a series of perioperative measures based on the evidence, in order to achieve a better recovery of the patient and a decrease of the complications and the mortality. These ERAS programs initially proved their advantages in the field of colorectal surgery being progressively adopted by other surgical areas within the general surgery and other surgical specialties. The main excluding factor for the application of such programs has been the urgent clinical presentation, which has caused that despite the large volume of existing literature on ERAS in elective surgery, there are few studies that have investigated the effectiveness of these programs in surgical patients in emergencies. The aim of this article is to show ERAS measures currently available according to the existing evidence for emergency surgery.  相似文献   
4.
6-Hydroxydopamine (6-OHDA) is a neurotoxin used in the induction of experimental Parkinson's disease in both animals and cultured neuronal cells. Biochemical and molecular approaches showed previously that low doses of 6-OHDA induced apoptosis in PC12 cells, while high doses of this neurotoxin induced necrosis. Melatonin has been shown to protect against the neuronal programmed cell death induced by 6-OHDA, although it was not able to prevent the massive necrotic cellular death occurring after the addition of high doses of the neurotoxin. In the present work, we demonstrate by ultrastructural analysis that although low doses of 6-OHDA induced apoptosis in PC12 cells, it also damaged the non-apoptotic cells, morphologically corresponding this damage to incipient and reversible necrotic lesions. When the doses of the neurotoxin increase, there are still apoptotic cells, although most of the cells show necrotic irreversible lesions. We also found that melatonin partially prevents the incipient necrotic lesions caused by low doses of 6-OHDA. The fact that melatonin was shown in previous work to prevent apoptosis caused by low doses of 6-OHDA, but not necrosis induced by high doses of the neurotoxin, seemed to indicate that this agent is only able to protect against apoptosis. However, our present results, melatonin preventing also the incipient necrotic neuronal lesions, suggest that this hormone may provide a general protection against cell death, suggesting that higher doses should be tried in order to prevent the necrotic cell death induced by high doses of the neurotoxin.  相似文献   
5.
New quinoxaline 1,4-di-N-oxides for treatment of tuberculosis   总被引:1,自引:0,他引:1  
Some quinoxaline 1,4-di-N-oxides derivatives with very different substituents in 2, 3, 6 and 7 positions have been synthesized in order to obtain new hypoxia selective agents. Some of these products have been tested as antituberculosis agents and very interesting results have been obtained from the first screening.  相似文献   
6.
OBJECTIVE: Using highly informative microsatellite markers flanking the neurofibromatosis type 2 gene, we determined the frequency of chromosome 22 allele loss in vestibular schwannomas. DESIGN: Peripheral lymphocyte/vestibular schwannoma DNA pairs were analyzed with five different microsatellite markers on chromosome 22. PATIENTS: Samples were taken from 32 patients (17 females and 15 males). Twenty-seven tumors occurred sporadically, and five were from patients with neurofibromatosis type 2. RESULTS: Using the microsatellite markers D22S351, CRYB2, D22S268, D22S304, and interleukin type 2RP3, we found loss of heterozygosity for at least two markers in 12 tumors. Ten tumors showed loss of heterozygosity for markers flanking the neurofibromatosis type 2 gene. Although microsatellite markers require little DNA for analysis and are highly informative, allele patterns may be difficult to interpret in some cases. CONCLUSIONS: Loss of heterozygosity of chromosome 22 alleles was a frequent event in vestibular schwannomas. In 10 tumors, heterozygosity was lost for centromeric and telomeric markers indicating likely monosomy 22. However, 63% of tumors did not reveal a detectable chromosomal loss. Unless a second vestibular schwannoma locus exists, these tumors likely harbor point mutations in the neurofibromatosis type 2 gene or deletions below the level of resolution of the markers used in this study.  相似文献   
7.
We report the unusual case of a 43-year-old woman who presented with Romberg's progressive facial hemiatrophy and spontaneous scleral perforation in the ipsilateral eye, for which scleral grafting was performed. Histologic and ultrastructural examination of the scleral specimen revealed a noninflammatory lytic process. The location of the scleral loss, exactly on the line of the "en coup de sabre" atrophy, as well as the light microscopy and ultrastructural histopathologic findings suggest that the scleral destruction was a late manifestation of Romberg's disease.  相似文献   
8.
The clinical, radiographic and pathological features of eighty-eight cases of histologically verified intra-osseous ganglia in eighty-three patients are described. All were located in the subchondral bone adjacent to a joint and most frequently involved the hip, the ankle (medial malleolus), the knee and the carpal bones. Forty-seven of the eighty-three patients were male and all the patients were between fourteen and seventy-three years of age, with an average age of forty-one years. There are two fundamental types of intra-osseous ganglia, one apparently arising by penetration of juxta-osseous ganglion into the underlying bone, a mechanism proved in fourteen of our eighty-eight cases (16 per cent); in the remaining seventy-four cases, the ganglion cyst was primarily intra-osseous ("idiopathic"). The initial cause of the intramedullary mucoid degeneration is discussed. We believe that mechanical stress and repeated minor trauma near the surface of the bone may lead to intramedullary vascular disturbance with consequent foci of aseptic bone necrosis. The revitalisation of these areas causes fibroblastic proliferation, followed by mucoid degeneration of the connective tissue, possibly due to some unknown local factor. Curettage or excision is usually effective, and recurrence (only four cases) is exceptional.  相似文献   
9.
10.
Objective: Our aim is to evaluate the capacity of intrapartum translabial ultrasound (ITU) with pushing in the prediction of difficulty of fetal extraction in vacuum assisted deliveries. Prospective, observational study performed (2/2015–8/2015) on 75 nulliparous women, ≥37 weeks with singleton pregnancies at full dilatation who had ITU-with-pushing performed, previous to vacuum-placement for fetal extraction. Working on the translabial sagittal-plane, we assessed: Angle-Progression (AoP), Progression-Distance (PD) and Head-Direction (HD); in the axial plane we evaluated: Midline-Angle (MLA) and Head-Perineum-Distance (HPD). Vacuum extractions were classified as easy-difficulty (ED) (≤3 vacuum-pulls), difficult-unsuccessful (DD) (>3 vacuum-pulls). We did not assess occipito-posterior-presentations.

Results: Seventy nulliparous were studied (44-ED,26-DD). We observed no differences in obstetric, neonatal or intrapartum characteristics between the two study groups, with the following exceptions: newborn weight (3272?±?438?g versus 3540?±?372?g; p?=?0.011) and number of vacuum-pulls (1.4-ED-vs-4.4-DD; p?<?0.0005). AoP-pushing was 143.9°?±?14.6° in ED and 115.1°±?12.9° in DD (p?<?0.0005); Head-Up was 79.5% versus 38.4% (p?<?0.0005); PD-Pushing was 42.7?±?11.3?mm versus 30.4?±?9.8?mm (p?<?0.0005); MLA-Pushing was 27.6°±?26.6° versus 57.5°±26.5°(p=0.025); HPD-Pushing was 40.8?±?10.0?mm versus 47.4?±?10.9?mm (p?=?0.039).

Conclusion: We identified that the presence of an AoP-Pushing?>?128° predicts an Easy-Vacuum-Delivery (≤3 Vacuum-Pulls) in >85% of cases (Sen 80%–FPR 9.3%).  相似文献   
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