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51.
52.
Siebzehnrübl E Kohl J Dittrich R Wildt L 《Molecular and cellular endocrinology》2000,169(1-2):109-111
The freezing of human ovarian tissue may be the key for restoring fertility after systemic therapy of cancer. In contrast to others we investigated the survival rate of whole follicles, and had a special look at the granulosa cells. Ovarian tissue was collected laparoscopically (n = 10) and divided into equal parts for freezing (n = 1570) or as control (n = 1660). The cryopreservation was done slowly, or as a ultrarapid freezing. After thawing the number of follicles, oocytes and granulosa cells surviving was counted and corrected for equal volumina of the samples. While 84.5% of the oocytes survived freezing, only 40.4% of the follicles were intact after thawing. The data show that the procedure damaged follicles, which mainly affected the granulosa cells. As the intactness of follicles may play a critical role for the maturation of the oocytes after thawing the protocols should be optimised to meet the needs of oocytes and granulosa cells. 相似文献
53.
S Kohl M S West C G Prober W M Sullender L S Loo A M Arvin 《The Journal of infectious diseases》1989,160(5):770-776
The role of antiviral antibodies in protection against neonatal herpes simplex virus (HSV) infection remains controversial. The relationship between neonatal and maternal anti-HSV antibodies and disease presentation was analyzed in 47 babies. Of the neonates, 77% had localized and 23% had disseminated HSV infection. Antibody-dependent cellular cytotoxic (ADCC) antibodies were evaluated in comparison with HSV neutralizing antibodies. High maternal (greater than 1:10(4)) or neonatal (greater than 1:10(3)) anti-HSV ADCC antibody levels or high neonatal antiviral neutralizing levels (greater than 1:20) were independently associated with an absence of disseminated HSV infection. Cochran-Mantel-Haenszel analysis demonstrated that ADCC levels were associated with disease status (P less than .02) while controlling for the level of neutralizing antibody. 相似文献
54.
Mark P Maskery Christian Holscher Stephanie P Jones Christopher I Price W David Strain Caroline L Watkins David J Werring Hedley CA Emsley 《Journal of cerebral blood flow and metabolism》2021,41(1):14
Stroke mortality and morbidity is expected to rise. Despite considerable recent advances within acute ischemic stroke treatment, scope remains for development of widely applicable neuroprotective agents. Glucagon-like peptide-1 receptor agonists (GLP-1RAs), originally licensed for the management of Type 2 Diabetes Mellitus, have demonstrated pre-clinical neuroprotective efficacy in a range of neurodegenerative conditions. This systematic scoping review reports the pre-clinical basis of GLP-1RAs as neuroprotective agents in acute ischemic stroke and their translation into clinical trials. We included 35 pre-clinical studies, 11 retrospective database studies, 7 cardiovascular outcome trials and 4 prospective clinical studies. Pre-clinical neuroprotection was demonstrated in normoglycemic models when administration was delayed by up to 24 h following stroke induction. Outcomes included reduced infarct volume, apoptosis, oxidative stress and inflammation alongside increased neurogenesis, angiogenesis and cerebral blood flow. Improved neurological function and a trend towards increased survival were also reported. Cardiovascular outcomes trials reported a significant reduction in stroke incidence with semaglutide and dulaglutide. Retrospective database studies show a trend towards neuroprotection. Prospective interventional clinical trials are on-going, but initial indicators of safety and tolerability are favourable. Ultimately, we propose that repurposing GLP-1RAs is potentially advantageous but appropriately designed trials are needed to determine clinical efficacy and cost-effectiveness. 相似文献
55.
During the period from January 1970 until December 1973, therapy was started in 41 previously untreated adolescents and adults with acute lymphoblastic leukemia. Induction therapy was started with vincristine and prednisone in all patients, resulting in complete remission in 19 and death due to infection during the first month in one case. After 3 wk on these two drugs, the addition of daunorubicin was required in the remaining 21 patients. Fifteen of these obtained remission, one died during induction therapy, and five patients were unresponsive to this therapy, as well as to all subsequent induction schemes. The overall remission rate was 83%. Significantly higher initial leukocyte counts were found in the group treated with vincristine, prednisone, and daunorubicin. Meningeal leukemia prophylaxis, by either periodic methotrexate injections given intrathecally or a combination of cranial irradiation and intrathecally administrated methotrexate, was administered in 29 therapy responders. The median duration of complete remission obtained with various maintenance therapy schemes was 13 mo. No differences were seen in the results obtained in patients between 14 and 20 yr of age and older patients. Twenty-two patients relapsed within 2-37 mo. Relapses were confined to the central nervous system in two cases, to the bone marrow in 18, and to the bone marrow and CNS simultaneously in two. A second remission was obtained in 17 cases (77%). The median survival time of the whole group was 27 mo, as compared with 32 mo for therapy responders and 7 mo for the nonresponders. The percentage and duration of remission and the survival time in our group of adolescents and adults were comparable to those currently being achieved in other centers, but not as good as those reported for children treated with the same protocols. 相似文献
56.
Fetal persistent middle cerebral artery reversed end diastolic flow is a rare and ominous finding. Previous cases have been associated with intracranial hemorrhage, growth restriction, anaemia, and hepatic anomaly. Intrauterine demise or early neonatal death is a common outcome. We report the case of persistent middle cerebral artery reversed end diastolic flow in a well-grown fetus at 32 weeks’ gestation resulting from acute, severe anaemia due to a large feto-maternal hemorrhage. An emergency cesarean section was performed and the neonate required advanced resuscitation and immediate blood transfusion. Postnatal magnetic resonance imaging confirmed a hemorrhagic parietal infarct and bilateral ischaemic changes in the basal ganglia. This provides further evidence that persistent middle cerebral artery reversed end diastolic flow in any fetus is an ominous finding warranting urgent diagnostic evaluation and/or delivery. 相似文献
57.
Autologous bone marrow transplantation for acute myeloid leukemia using busulfan plus etoposide as a preparative regimen 总被引:1,自引:0,他引:1
We have studied the use of a new preparative regimen for the treatment of patients in remission of acute myeloid leukemia (AML) with autologous bone marrow transplantation. Chemotherapy consisted of busulfan 1 mg/kg every 6 hours for 4 days (total dose, 16 mg/kg) on days -7 through -4 followed by an intravenous infusion over 6 to 10 hours of etoposide 60 mg/kg on day -3. Autologous bone marrow, treated in vitro with 100 micrograms/mL of 4-hydroperoxycyclophosphamide, was infused on day 0. We have treated 58 patients up to the age of 60 years, 32 in first remission, 21 in second or third remission, and 5 with primary refractory AML unresponsive to high-dose Ara-C, but achieving remission with aggressive salvage regimens. Of the first remission patients, there has been 1 treatment related death and 5 relapses. With median follow-up of 22 months, the actuarial relapse rate is 22% +/- 9% and disease-free survival is 76% +/- 9% at 3 years. Patients with favorable French-American-British (FAB) subtypes (M3 or M4 EO) did especially well, with no relapses seen in 15 patients observed for a median of 30 months. Actuarial relapse rate at 3 years was 48% for first remission patients with less favorable FAB subtypes. Of patients in second or third remission, there were 5 treatment related deaths and 4 relapses. With median follow-up of 22 months, the actuarial relapse rate is 25% +/- 11% and disease-free survival is 56% +/- 11% at 3 years. Four of five primary refractory patients died during treatment and 1 remains in remission with short follow-up. These preliminary data are very encouraging and, if confirmed, support the use of autologous purged bone marrow transplantation using aggressive preparative regimens as one approach to improve the outcome of adults with AML. 相似文献
58.
59.
Flora Maria Lorenzo Fortes Ney Boa Sorte Victor D Mariano La la D Andrade Fernanda A Oliveira Monique CA Santos Cl udia Ivanilda N dos Santos Catharina A Passos Mila P Pacheco Valdiana C Surlo Neog lia P de Almeida Jaciane AM Fontes r a M Pimentel Raquel Rocha Genoile Oliveira Santana 《World journal of gastroenterology : WJG》2020,26(44):6993-7004
BACKGROUNDThere has been an increase in cases of inflammatory bowel disease (IBD) in recent years. There is also greater access and availability of immunosuppressive and biological agents, which increase the risk of opportunistic infection despite improving the quality of life and promoting mucosal healing. Tuberculosis (TB) remains a public health problem, and it has a high incidence in several countries. Therefore, knowledge of the risk of developing TB in patients with IBD is important.AIMTo evaluate the risk of active TB in patients with IBD under treatment from an endemic area in Latin America.METHODSA standard questionnaire included demographic variables, clinical aspects of IBD disease, history of active TB during treatment, active TB characteristics and evolution, initial screening and results and time from the start of anti-tumor necrosis factor alpha (TNFα) to TB development.RESULTSAzathioprine, anti-TNFα and the combination of these two drugs were associated with a higher risk of active TB incidence. The TNFα blockers increased the relative risk of developing active TB compared to other treatments. All four multivariable models showed that the use of TNFα blockers alone or in combination with azathioprine was an important risk factor for the incidence of active TB. After adjustment for sex, age, type of IBD and latent TB, anti-TNFα with azathioprine increased the relative risk to 17.8 times more than conventional treatment. Late TB, which was diagnosed 3 mo after the start of anti-TNFα, was the most frequent.CONCLUSIONTreatment with anti-TNFα increased the risk of active TB in IBD patients from an endemic area in Latin America. This risk was increased when anti-TNFα was combined with azathioprine. The time from the beginning of the treatment to the active TB diagnosis suggests a new TB infection. 相似文献
60.
AIM: The aim of this study was to investigate the response of primary human cementoblasts to conditions as they occur on the pressure side during orthodontic tooth movement. METHODS: In our previous study, the cementoblasts were characterized using markers for osteoblastogenic differentiation and the cementoblast-specific marker CEMP-1. Initially, primary human cementoblasts were compressed for 1?h, 4?h, and 6?h (30?g/cm(2)). In the second experiment, the cementoblasts were stimulated with interleukin (IL)-1β for 24?h and for 96?h with 1?ng/ml and 10?ng/ml and subsequently compressed for 1?h and 6?h. Changes in mRNA expression for receptor activator of NF-κB (RANK), RANK ligand (RANKL), osteoprotegerin (OPG), and cyclooxygenase-2 (COX-2) were measured by quantitative real-time polymerase chain reaction (RT-PCR). RANK and RANKL were also examined by immunocytochemical staining at the protein level. RESULTS: Compression (30?g/cm(2)) led to a significant increase in RANKL expression after 6?h. OPG expression in compressed cementoblasts was significantly reduced after 1?h. RANK remained unchanged during the course of the experiment. Stimulation with IL-1β induced RANKL and OPG expression. However, IL-1β-dependent induction of RANKL was more prominent than the induction of OPG, leading to a (significant) increase in the RANKL/OPG ratios. The expression of RANK remained unchanged after 24?h of stimulation with IL-1β and decreased significantly after 96?h. Compression of the prestimulated cells resulted in a further increase in RANKL expression significant after 6?h. OPG and RANK expression remained unchanged compared to the unstimulated sample. COX-2 increased significantly after both compression and stimulation with IL-1β. Combined stimulation and compression resulted in a significant further increase after 6?h compared to IL-1β stimulation alone. CONCLUSION: Primary human cementoblasts in vitro express increased levels of RANKL, in particular during the combination of inflammation and compression. The increase in RANKL expression is not compensated by an increase in OPG expression. The induction of RANKL expression was associated with a significant increase in COX-2 expression. Since RANKL attracts osteoclasts, its increase might be associated with the progression of root resorption. The in vitro alterations in cementoblasts we observed may be indicators of cellular mechanisms that lead to the increased root resorption during orthodontic treatment. 相似文献