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991.
Marler L Conda-Sheridan M Cinelli MA Morrell AE Cushman M Chen L Huang K Van Breemen R Pezzuto JM 《Anticancer research》2010,30(12):4873-4882
In the search for agents with cancer chemopreventive potential, 14-chloromethyl-12H-5,11a-diazadibenzo[b,h]fluoren-11-one (compound 1), originally synthesized as a potential topoisomerase I inhibitor, and 2,4-dibromo-1-hydroxyphenazine (compound 2), an analog of a substance found in the marine bacteria Streptomyces CNS284, were found to significantly enhance NADP(H):quinone oxidoreductase 1 (QR1), glutathione S-transferase (GST), and glutathione (GSH) levels in cell culture. However, following a short-term absorption study, analyses of livers from the treatment groups did not reveal a significant increase in QR1 or GST activity, or GSH levels. This was consistent with RT-PCR analyses of tissue samples. The compounds were absorbed, as judged by LC/MS analyses of serum and tissue samples, although levels were well below the concentrations required to mediate in vitro responses. Metabolites of compound 2 formed in vitro by human liver microzones were characterized using high resolution tandem mass spectrometry. In sum, the in vivo activity of these compounds appears to be diminished by low bioavailability, but this experimental approach indicates the importance of systematic biomarker investigation. 相似文献
992.
Davide Mauri Sofia Roumbkou Stella Michalopoulou Lamprini Tsali Anastasia Spiliopoulou Charalampos Panou Antonis Valachis Angelos Panagopoulos Nikolaos P. Polyzos 《Medical oncology (Northwood, London, England)》2010,27(4):1309-1313
Central venous catheters (CVCs) are commonly used for the administration of intravenous chemotherapy in outpatient setting.
Nevertheless, outbreaks of catheter-associated bloodstream infections had been reported from oncology centers. We describe
a large outbreak of CVCs-associated Klebsiella oxytoca bloodstream infection, occurring in an oncology chemotherapy outpatient unit of northern Greece between October 2006 and
May 2007. The outbreak involved approximately 10% of the patients with CVCs who were receiving home-based chemotherapy, and
it represents the second larger outbreak of CVCs-associated BSIs due to Klebsiella oxytoca in oncology outpatient centers. We retrospectively analyzed the chain of investigations and prophylactic/diagnostic measures
taken to eradicate the infection: (1) patients’ chart audit, (2) estimation of the infection among asymptomatic patients,
(3) implementation of the level of awareness of medical and paramedical personnel, (4) collection of samples from environment,
medications and infusion materials, (5) critical appraisal of chemotherapeutical schemes and (6) cooperation with peripheral
institutions. The isolation of Klebsiella oxytoca in a chemotherapy solution (infusional 5-FU in dextrose 5% solution within a 48 h pump) from a peripheral General Hospital
and the prompt transmission of the data to the chemotherapy center played a key role for the management of the infection cluster.
This is the first report that evidenced the detection of Klebsiella oxytoca within a chemotherapeutical preparation. Data transmission from peripheral hospitals to the central institution resulted
in an important feedback that allowed a better estimation of the infection cluster and more tailored actions for the eradication
of the infection. 相似文献
993.
Alessandra Estrela-Lima Márcio SS Araújo João M Costa-Neto Andréa Teixeira-Carvalho Stella M Barrouin-Melo Sergio V Cardoso Olindo A Martins-Filho Rogéria Serakides Geovanni D Cassali 《BMC cancer》2010,10(1):256
Background
The immune system plays an important role in the multifactorial biologic system during the development of neoplasias. However, the involvement of the inflammatory response in the promotion/control of malignant cells is still controversial, and the cell subsets and the mechanisms involved are poorly investigated. The goal of this study was to characterize the clinical-pathological status and the immunophenotyping profile of tumor infiltrating lymphocytes and their association with the animal survival rates in canine mammary carcinomas. 相似文献994.
Catalina D. Alba Soto Maria Elisa Solana Carolina V. Poncini Agustina M. Pino-Martinez Valeria Tekiel Stella Maris González-Cappa 《Vaccine》2010
In diverse models of microbial infections, protection is improved by immunization with dendritic cells (DC) loaded with whole pathogen lysate. However, pathogens that modulate DC function as a way to evade immunity may represent a challenge for these vaccination strategies. Thus, DC must be instructed in a particular manner to circumvent this issue and drive an effective immune response. Trypanosoma cruzi or its molecules alter DC function and, as we demonstrated, this phenomenon is associated with the parasite-driven stimulation of IL-10 production by DC. Here, we show that DC from IL-10-deficient mice pulsed in vitro with trypomastigote lysate secreted increased amounts of Th1-related cytokines and stimulated higher allogeneic and antigen-specific lymphocyte responses than their wild-type counterparts. In a model of DC-based immunization, these antigen-pulsed IL-10-deficient DC conferred protection against T. cruzi infection to recipient mice. Efficient immunity was associated with enhanced antigen-specific IFN-gamma production and endogenous DC activation. We illustrate for the first time a DC-based vaccination against T. cruzi and evidence the key role of IL-10 produced by sensitizing DC in inhibiting the induction of protection. These results support the rationale for vaccination strategies that timely suppress the effect of specific cytokines secreted by antigen presenting DC. 相似文献
995.
Stefania Mondello Domenico Italiano Maria Stella Giacobbe Patrizia Mondello Giuseppe Trimarchi Carmela Aloisi Placido Bramanti Edoardo Spina 《Nutrition (Burbank, Los Angeles County, Calif.)》2010,26(6):677-681
ObjectiveGlutamine is an important substrate for critical cells of the immune system, in particular lymphocytes and macrophages, and it is considered a conditionally essential amino acid. Several studies have indicated that glutamine-enriched total parenteral nutrition improves immunologic status and shortens length of stay of critically ill patients. We investigated the effect of total parenteral nutrition supplemented with glutamine on the immune system in anorectic patients.MethodsThirty-six anorectic patients were randomized to receive standard parenteral nutrition or parenteral nutrition supplemented with glutamine 0.18 g · kg?1 · d?1 for 20 d. To evaluate the immune system status, we determined serum levels of neopterin and insulin growth factor-1 and lymphocyte count at baseline and after 10 and 20 d from the beginning of the therapy.Results and ConclusionsThe results showed a significant increase of the serum levels of neopterin after 10 d of treatment with glutamine (26.44 ± 3.08 versus 6.75 ± 1.73 nmol/L, P < 0.001), thus proving a probable stimulating action carried out by glutamine on the immune system, as testified by the increase of lymphocytes. 相似文献
996.
997.
Enrico Papaleo Valeria Stella Vanni Paola Viganò Antonio La Marca Luca Pagliardini Rossella Vitrano 《Gynecological endocrinology》2014,30(11):813-816
Poor ovarian response (POR) is most frequently linked to the condition known as diminished ovarian reserve, but it can also occur in the absence of pathological ovarian reserve tests (“unexpected” POR). Because possible explanations include theca cells function deficiency, our aim was to evaluate the effect of r-LH administration in “unexpected” poor responders.A retrospective, single-centre, cohort study was conducted on 65 patients with AMH >0.5?ng/ml and/or AFC >5 with POR in their first cycle. Patients underwent a second IVF cycle with same protocol (long- or antagonist) and same starting dose of r-FSH used in the first cycle, plus daily addiction of 150?IU of r-LH from day 1.Compared to the first cycle, r-LH addition in the second cycle determined an increase in number of oocytes retrieved (p?0.001), number of metaphase II oocytes (p?0.05), E2 levels at hCG triggering (p?0.001) and number of embryos transferred (p?=?0.002). A 15% clinical pregnancy rate was also observed in the second cycle.Our results suggest that patients with non-pathological ovarian reserve tests and previous “unexpected” POR seem to benefit from r-LH addition in subsequent cycles without the need to increase the r-FSH starting dose, possibly due to an underlying occult theca cells deficiency. 相似文献
998.
Stella Tammaro Roberta Caruso Francesco Pallone Giovanni Monteleone 《World journal of gastroenterology : WJG》2012,18(34):4635-4638
Acute pancreatitis is the most common serious complication of endoscopic retrograde cholangio-pancreatography (ERCP) and its incidence may exceed 25% in some high-risk patient subsets. In some patients, pancreatitis may follow a severe course with pancreatic necrosis, multiorgan failure, permanent disability and even death. Hence, approaches which minimize both the incidence and severity of post-ERCP pancreatitis are worth pursuing. Pancreatic stents have been used with some success in the prevention of post-ERCP, while so far pharmacological trials have yielded disappointing results. A recent multicenter, randomized, placebo-controlled, double-blind trial has shown that rectally administered indomethacin is effective in reducing the incidence of post-ERCP pancreatitis, the occurrence of episodes of moderate-to-severe pancreatitis and the length of hospital stay in high-risk patients. These results together with the demonstration that rectal administration of indomethacin is not associated with enhanced risk of bleeding strongly support the use of this drug in the prophylaxis of post-ERCP pancreatitis. 相似文献
999.
Giulia Iapadre Giovanni Morana Maria Stella Vari Francesca Pinto Paola Lanteri Alessandra Tessa Filippo Maria Santorelli Pasquale Striano Alberto Verrotti 《European journal of paediatric neurology》2018,22(3):563-567
Background
Charcot-Marie-Tooth (CMT) neuropathies represent the most common forms of inherited polyneuropathies. CMT2A, the axonal form, accounts for about one third of all CMT cases. Variants in the MFN2 gene have been recognized to be a major cause of CMT2A. To date, more than 100 pathogenetic mutations in MFN2 have been identified, leading to different neurological clinical spectrum, varying from hereditary neuropathies to more severe clinical phenotypes. Pathogenic variants in MFN2 mainly act in a dominant manner, although in a few sporadic or familial cases, homozygous or compound heterozygous mutations have been reported.Results
We describe a child carrying a novel homozygous MFN2 mutation leading to an early-onset sensorimotor axonal neuropathy with an atypical and severe phenotype.Conclusion
The case highlights a very rare mechanism of inheritance for MFN2 mutations and expands the clinical and allelic variance of severe CMT2A phenotype. Moreover, it proposes the involvement of cerebellar peduncles observed at neuroimaging as a novel clue to suspect the diagnosis and address genetic testing. 相似文献1000.