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51.
Prostaglandins play a critical role in tumor development and growth by regulating numerous biologic processes, including tumor angiogenesis, with clear prognostic and therapeutic implications. The aim of this study was to investigate the prognostic relevance of cyclooxygenase-2 (COX-2) pathway activation in head and neck squamous cell carcinoma (HNSCC). COX-2 activity was analyzed in 52 consecutive patients by assessing protein expression and prostaglandin E(2) (PgE(2)) levels and was then correlated to vascular endothelial growth factor (VEGF) expression and tumor angiogenesis. We evaluated the prognostic impact of these parameters by Kaplan-Meier and Cox survival analysis. COX-2 expression by tumor cells was closely correlated to VEGF expression and to tumor vascularization. According to Kaplan-Meier analysis, patients with COX-2 tumor overexpression and with higher PgE(2) tumor levels had significantly shorter overall survival estimates (P = 0.022 and P = 0.033, respectively). Analogously, patients with more-vascularized tumors had worse survival than those with less-vascularized cancers (P = 0.032). Cox multivariate analysis demonstrated that the most significant prognostic factors were presence of lymph node metastasis, tumor vascularization, COX-2 protein expression, and PgE(2) tumor levels. This study demonstrates a close correlation between COX-2 pathway, VEGF expression, and tumor angiogenesis in HNSCC. In addition, COX-2 overexpression and higher tumor vascularization appear to predict a shorter survival in patients with head and neck cancer.  相似文献   
52.
Several methods have been developed to detect common prothrombotic mutations, including factor V Leiden (G1691), prothrombin G20210A, and methylenetetrahydrofolate reductase (MTHFR) C677C. In this study, we compared the accuracy of three different molecular techniques, i.e.: (1) restriction enzyme digestion (RFLP), (2) real time with hybridization probes and final melting curve (Fluorescence Resonance Energy Transfer, FRET), and (3) real time with hydrolysis probes (TaqMan®). Sequencing was used as the reference standard. Our data showed that RFLPs analysis for the detection of prothrombotic mutations, albeit easy-to-perform, had a limited reliability for assessing correct genotypes. FRET analysis displayed higher resolution than RFLPs. Additionally, FRET analysis was faster and less tedious than sequencing.  相似文献   
53.
Penetrating chest trauma leading to selective coronary artery injury is uncommon. Their incidence is not accurately established because the clinical diagnosis is difficult and the lesion is often revealed only during autopsy. The mortality rate remains high. We report a fatal case of selective right coronary artery injury due to a penetrating wound directed to the right chest.  相似文献   
54.

Purpose

To analyse the impact of female characteristics on assisted reproductive technology outcome among male haematological cancer survivors.

Methods

A retrospective analysis of 93 haematological cancer survivors attending our tertiary referral fertility centre between June 1998 and June 2017 for achieving fatherhood with assisted reproductive technology treatments.

Results

A progressive increase in the median female age was observed during the study period (32.2 years until the year 2007 and 36.9 years from the year 2012). Fifty-five out of 93 patients were treated with intracytoplasmic sperm injection (ICSI) (113 ovarian stimulations, 108 ICSI procedures). Cryopreserved ejaculated sperm was used in 28 couples, fresh sperm in 19, and thawed testicular sperm in 8 couples. Mean female age at ovarian stimulation was 37.0 ± 4.7 years. Twenty-six pregnancies resulted in a full-term birth (23% per started ovarian stimulation; 43.6% per couple) and 33 children were born. No significant differences were observed according to source of sperm (fresh, frozen, testicular) and multivariate analysis confirmed that maternal age was the only variable inversely related to the cumulative delivery rate, being five times lower (15.7%) when the female partner was ≥?40 years (OR?=?0.22, 95% CI 0.06–0.77) vs. 58.3% with younger women (p?=?0.0037).

Conclusions

Delayed childbearing and female ageing affect ICSI outcome in couples where the male is a survivor of haematological cancer. This topic should be discussed when counselling male cancer patients about fertility preservation.
  相似文献   
55.

Background

Most children with cancer live in developing countries where the prevalence of malnutrition may reach 50% and influence the course of the disease. This study examined the prevalence and severity of malnutrition at diagnosis, as well as after 3 and 6 months of chemotherapy, in children with acute lymphoblastic leukemia (ALL) in Guatemala.

Methods

Triceps skin fold thickness (TSFT) and mid upper arm circumference (MUAC) provided measures of nutritional status (NS) in three categories: adequately nourished (A): TSFT and MUAC > 10th percentile; severely depleted (SD): TSFT or MUAC < 5th percentile; and moderately depleted (MD): all the remaining patients.

Results

Of 331 new patients, 241 had NS assessed at diagnosis. A = 113 (46.9%); MD = 28 (11.6%); SD = 100 (41.5%). At 3 months A = 106 (52.2%); MD = 25 (12.3%); SD = 72 (35.5%). At 6 months A = 146 (76.0%); MD = 12 (6.3%); SD = 34 (17.7%). In multivariate analysis, SD children at 6 months of treatment had a hazard of death that was 2.4‐fold the hazard of those A or MD (95% CI: 1.3–4.7)

Conclusions

Malnutrition is prevalent in newly diagnosed children with ALL in Guatemala and severe nutritional depletion is apparently predictive of abandonment of therapy and relapse of disease, but if children survive and improve their NS in the first 6 months after diagnosis, their chances of survival may improve significantly to approximate those in children not presenting with nutritional depletion. Pediatr Blood Cancer 2013; 60: 911–915. © 2012 Wiley Periodicals, Inc.  相似文献   
56.
Accurate prediction of the impact of genomic variation on phenotype is a major goal of computational biology and an important contributor to personalized medicine. Computational predictions can lead to a better understanding of the mechanisms underlying genetic diseases, including cancer, but their adoption requires thorough and unbiased assessment. Cystathionine‐beta‐synthase (CBS) is an enzyme that catalyzes the first step of the transsulfuration pathway, from homocysteine to cystathionine, and in which variations are associated with human hyperhomocysteinemia and homocystinuria. We have created a computational challenge under the CAGI framework to evaluate how well different methods can predict the phenotypic effect(s) of CBS single amino acid substitutions using a blinded experimental data set. CAGI participants were asked to predict yeast growth based on the identity of the mutations. The performance of the methods was evaluated using several metrics. The CBS challenge highlighted the difficulty of predicting the phenotype of an ex vivo system in a model organism when classification models were trained on human disease data. We also discuss the variations in difficulty of prediction for known benign and deleterious variants, as well as identify methodological and experimental constraints with lessons to be learned for future challenges.  相似文献   
57.
The effects of heterologous gene dosage as well as Salmonella typhimurium strain variability on immune response toward both the heterologous antigen, the nontoxic mutant of the Escherichia coli heat-labile enterotoxin LTK63, and the carrier Salmonella strain have been analyzed. Effects of a single integration into the host DNA and different-copy-number episomal vectors were compared in S. typhimurium Δcya Δcrp Δasd strains of two different serotypes, UK-1 and SR-11. Expression of the enterotoxin in the different Salmonella isolates in vitro was found to vary considerably and, for the episomal vectors, to correlate with the plasmid copy number. LTK63-specific serum immunoglobulin G (IgG) and mucosal immunoglobulin A (IgA) antibodies were highest in mice immunized with the high-level-expression strain. High anti-LTK63 IgG and IgA titers were found to correspond to higher anti-Salmonella immunity, suggesting that LTK63 exerts an adjuvant effect on response to the carrier. Statistically significant differences in anti-LTK63 immune response were observed between groups of mice immunized with the attenuated Δcya Δcrp UK-1 and SR-11 derivatives producing the antigen at the same rate. These data indicate that the same attenuation in S. typhimurium strains of different genetic backgrounds can influence significantly the immune response toward the heterologous antigen. Moreover, delivery of the LTK63 enterotoxin to the immune system by attenuated S. typhimurium strains is effective only when synthesis of the antigen is very high during the initial phase of invasion, while persistence of the S. typhimurium strain in deep tissues has only marginal influence.

Enterotoxigenic Escherichia coli strains produce a plasmid-encoded heat-labile enterotoxin (LT) (15, 34) related to cholera toxin (CT) (9, 35). LT is composed of two subunits, A and B, which are exported to the periplasmic space, where they assemble into an AB5 multimeric complex (16). Several mutants of LT-A have been constructed, and in particular, a nontoxic mutant which contains a substitution of serine 63 with lysine (LTK63) has been shown to maintain the structural and immunogenic properties of wild-type LT (21, 27, 28). LTK63 has also been found to display the strong mucosal adjuvant activity pertaining to wild-type LT. Efficient induction of mucosal immune response, specifically in the mouse vagina, has been achieved via the intranasal route of immunization (10). For the development of oral vaccines, however, it would be desirable to exploit the properties of LTK63 for enhancing antigen-specific immune response in the intestinal mucosa by means of oral delivery of the potent mucosal adjuvant.Oral delivery of antigens by live vaccines is known to lead to a more effective production of antigen-specific antibodies in mucosal secretions than oral administration of the soluble antigen (36, 39). Several antigen delivery systems which use as carriers mutant intracellular pathogens that have lost the ability to persist and produce the disease while retaining limited growth in vivo have been developed. In particular, attenuated Salmonella mutants are suitable immunological carriers for virulence determinants from other enteric bacteria in that they can induce humoral immune response selectively at the site of colonization, the gut mucosa. Vaccine strains of Salmonella have been successfully attenuated by introducing different types of mutations (5, 8, 23, 26). Notably, Salmonella strains with a galactose epimerase (galE) mutation (18) or deletions in genes for the biosynthesis of aromatic compounds (aro mutants) (11, 12, 17, 19) or in the adenylate cyclase (cya) and cyclic AMP receptor protein (crp) genes (6) are the most extensively characterized.Delivery of the B subunit of the E. coli enterotoxin (LT-B) by a galE mutant of Salmonella typhimurium has been shown to elicit low levels of anti-LT-B serum and mucosal antibodies. Since the vector used for expression of LT-B was rapidly lost in vivo, i.e., in the absence of the antibiotic required for selection of the plasmid, the level of immune response could be correlated only with the amount of antigen expressed during the initial phase of invasion (3).Recently, direct comparison between the aroA aroD/pnirB and the Δcya Δcrp Δasd/asd+ delivery systems for the ability to induce humoral and cellular immunity after a single immunization showed that the former vaccine strain had greater potential as a carrier for antigen delivery (20). However, the balanced lethal asd system for in vivo selection of plasmids expressing heterologous antigens in the attenuated Δcya Δcrp Δasd strains is still very attractive in that asd+ plasmids do not require antibiotic resistance markers for selection while stably maintained in vivo (24). In addition, the Δcya Δcrp Δasd/asd+ delivery system has been reported to induce protective immunity against several pathogens (25, 29, 40). Most of these studies have restricted analysis of the immune response to antigens expressed from the same asd+ plasmid carried by Δcya Δcrp Δasd mutants usually of the same S. typhimurium serotype. In this work, we have analyzed the influence of heterologous gene dosage, and thus level of expression, as well as S. typhimurium strain variability on immune response toward both the heterologous antigen, a nontoxic mutant of E. coli LT, and the carrier Salmonella strain. Effects of a single integration into the host DNA and episomal vectors at different copy numbers were compared in S. typhimurium strains of two different Δcya Δcrp Δasd serotypes, UK-1 and SR-11.  相似文献   
58.
PURPOSE: We report the case of a male newborn with Ohtahara syndrome and right hemimegalencephaly who presented epileptic negative myoclonus in the first days of life. METHODS: Prolonged polygraphic studies were performed, as well as MRI and a full clinical examination. RESULTS: EEG showed a constant and nonreactive pattern of burst suppression. There were several kinds of electro-clinical seizures (generalized myoclonia, short atonias, typical spasm and tonic spasms) at the beginning of the EEG's burst. The periods of EMG silence, lasting less than 300 ms, were associated with stereotyped EEG transients. CONCLUSIONS: Epileptic negative myoclonus can be observed also in neonatal age. The short transient impairment of motor function observed in the newborn seems linked to the slow component of spike-wave discharge, but its mechanism is still not clear.  相似文献   
59.
We report two cases of histoplasmosis occurring in human immunodeficiency virus-positive patients who immigrated to Italy, and focus our attention on the clinical features and therapeutic aspects, with particular emphasis on secondary prophylaxis. The patients had comparable human immunodeficiency virus baseline parameters, but had a completely different compliance over therapeutic regimens. The two patients were followed in two different city hospitals of our region, Padua and Verona, and the diagnosis was made on the basis of instrumental, histologic, and microbiologic findings. One of them was treated with corticosteroids because of nephrotic syndrome.  相似文献   
60.
Glycoprotein Po (Po) and peripheral myelin protein 22 (PMP22) are two proteins playing a crucial physiological role in the maintenance of the multilamellar structure of peripheral myelin. We here demonstrate that the removal of circulating androgens by orchidectomy induces a significant decrease of the synthesis of Po and PMP22 in the rat sciatic nerve. In case of Po, this effect may be counteracted by the subsequent treatment with testosterone metabolites, dihydrotestosterone or 5alpha-androstan-3alpha,17beta-diol (3alpha-diol). Experiments have been consequently performed in order to evaluate the role of androgen receptor (AR) in the control of Po synthesis. In vivo treatment with flutamide (i.e., an antagonist of AR) induces a decrease of the synthesis of this myelin protein in the sciatic nerve of intact male rats confirming a role for this steroid receptor. On the contrary, PMP22 seems not to be under the control of AR, but a role for GABAA receptor may be proposed. This concept is based on the findings that: (a) only 3alpha-diol, which is able to interact with GABAA receptor, is effective in stimulating the synthesis of PMP22 in the sciatic nerve of castrated male rats, and (b) flutamide treatment is ineffective in decreasing the protein levels in intact male rats. The observations here reported clearly show similarities and dissimilarities with the effects exerted by other members of neuroactive steroid family, like for instance progesterone derivatives, which will be discussed in text.  相似文献   
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