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91.

Background

It has been suggested that selective sentinel node (SN) biopsy alone can be used to manage early breast cancer, but definite evidence to support this notion is lacking. The aim of this study was to investigate whether refraining from completion axillary lymph node dissection (ALND) suffices to produce the same prognostic information and disease control as proceeding with completion ALND in early breast cancer patients showing micrometastasis at SN biopsy.

Methods

This prospective, randomized clinical trial included patients with newly diagnosed early-stage breast cancer (T < 3.5 cm, clinical N0, M0) who underwent surgical excision as primary treatment. All had micrometastatic SN. Patients were randomly assigned to one of the two study arms: complete ALND (control arm) or clinical follow-up (experimental arm). Median follow-up was 5 years, recurrence was assessed, and the primary end point was disease-free survival.

Results

From a total sample of 247 patients, 14 withdrew, leaving 112 in the control arm and 121 in the experimental arm. In 15 control subjects (13 %), completion ALND was positive, with a low tumor burden. Four patients experienced disease recurrence: 1 (1 %) of 108 control subjects and 3 (2.5 %) of 119 experimental patients. There were no differences in disease-free survival (p = 0.325) between arms and no cancer-related deaths.

Conclusions

Our results strongly suggest that in early breast cancer patients with SN micrometastasis, selective SN lymphadenectomy suffices to control locoregional and distant disease, with no significant effects on survival.  相似文献   
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Some 70–80% of subjects with psychotic risk syndrome (PRS) have lifetime comorbidity, with depressive disorders being the most common. A high proportion of patients with PRS present nonspecific symptoms which can be confounding factors for diagnosis. Depressive and negative symptoms may be difficult to distinguish and it is important to differentiate them. The aim of this study is to assess the presence of depressive disorder in a child and adolescent sample of PRS and to examine the presence of negative symptoms and detect possible confounding characteristics between them and depressive symptoms. This is a naturalistic multi-site study with subjects who met PRS criteria. A sample of 89 PRS adolescent patients was included. Major depressive disorder (MDD) is the most prevalent comorbid disorder (34.83%). The sample was divided into patients who met criteria for MDD (PRS-MDD, n = 31) and those who did not have this disorder (PRS-ND, n = 44). We obtained significant differences in the attenuated negative symptoms (ANS) between PRS-MDD and PRS-ND (68.18 vs. 90.32%, respectively, p = 0.021). Subjects with MDD presented a higher score in ANS and Hamilton Depression Rating Scale (HDRS). Moreover, we obtained a correlation between negative symptomatology and HDRS score with a higher score on HDRS in subjects with higher negative symptom scores (r = 0.533, p < 0.001). More research is needed to fine tune differentiation between depressive and negative symptoms and learn more about the possible impact of MDD on PRS children and adolescents.

  相似文献   
95.
The B lymphocyte-activating factor belonging to TNF superfamily (BAFF) acts on B lymphocytes through BAFF receptor (BAFF-R), the transmembrane activator, calcium modulator, and cyclophilin ligand interactor (TACI), and the B cell maturation antigen (BCMA). Another cytokine, a proliferation-inducing ligand (APRIL), only binds to TACI and BCMA. In this study, we sought to determine the effect of Toll-like receptor agonists (TLR-A) on the expression of BAFF/APRIL receptors by murine splenic B lymphocytes. CpG oligodeoxynucleotides (ODN) and LPS strongly up-regulated TACI expression, while BAFF-R was only up-regulated by CpG ODN. CpG ODN pretreatment up-regulated TACI expression on follicular and marginal zone B lymphocytes and increased their responses to BAFF- and APRIL-mediated Ig secretion. TACI seemed to be playing a pivotal role in BAFF- or APRIL-induced Ig secretion because B lymphocytes from TACI-knockout mouse or the blocking of TACI with a neutralizing antibody resulted in total inhibition of IgA and IgG secretion in CpG ODN-pretreated and BAFF- or APRIL-stimulated B cells. Thus, CpG ODN-induced increase in TACI expression is likely to play an important role in Ig secretion following activation of B lymphocytes through TLR9.  相似文献   
96.
OBJECTIVE: To describe the relationship between blood lead levels (BLL) and poor school performance. MATERIAL AND METHODS: A cross-sectional study was carried out in 1996 among 792 schoolchildren aged 7-14 years, who attended the outpatient units of five pediatric hospitals of Mexico City. BLL was measured together with lead exposure and academic performance. RESULTS: Reported BLL and geometric means (GM) were 8.6 microg/dL and 7.7 microg/dL, respectively. The main source of exposure was the use of glazed pottery (difference of use =-1.182; p = 0.000). Among schoolchildren who failed any school year, GM of the BLL was 8.1 microg/dL, compared with children who did not fail (GM = 7.6 microg/dL; p = 0.240). The risk of failing a school year between the 1st and 3rd grade with a BLL greater than 10 microg/dL was 1.73 (p = 0.012, IC 95% 1.13-2.66) and from 1st to 4th grade was 1.62 (p = 0.021, IC 95% 1.07-2.46). CONCLUSIONS: Blood lead levels, among other conditions, may contribute to the failure in school performance observed in the children participating in this study.  相似文献   
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99.

Background

A new, simple and accurate stability-indicating reverse phase high performance liquid chromatography method was developed and validated during the early stage of drug development of an oral lyophilizate dosage form of cetirizine dihydrochloride.

Methods

For RP-HPLC analysis it was used an Eclipse XDB C8 column 150 mm × 4.6 mm, 5 μm (Agilent columns, Barcelona, Spain) as the stationary phase with a mobile phase consisted of a mixture of 0.2 M K2HPO4 pH 7.00 and acetonitrile (65:35, v/v) at a flow rate of 1 mL min −1. Detection was performed at 230 nm using diode array detector. The method was validated in accordance with ICH guidelines with respect to linearity, accuracy, precision, specificity, limit of detection and quantification.

Results

The method results in excellent separation between the drug substance and its stress-induced degradation products. The peak purity factor is >950 for the drug substance after all types of stress, which confirms the complete separation of the drug substance peak from its stress induced degradation products.Regression analysis showed r2 > 0.999 for cetirizine dihydrochloride in the concentration range of 650 μg mL −1 to 350 μg mL−1 for drug substance assay and a r2 > 0.999 in the concentration range of 0.25 μg mL−1 to 5 μg mL−1 for degradation products. The method presents a limit of detection of 0.056 μg mL −1 and a limit of quantification of 0.25 μg mL−1. The obtained results for precision and accuracy for drug substance and degradation products are within the specifications established for the validation of the method.

Conclusions

The proposed stability-indicating method developed in the early phase of drug development proved to be a simple, sensitive, accurate, precise, reproducible and therefore useful for the following stages of the cetirizine dihydrochloride oral lyophilizate dosage form development.  相似文献   
100.

Rationale

Atomoxetine (ATX) is a non-stimulant drug approved for the treatment of attention deficit hyperactivity disorder (ADHD). Although animal models have provided evidence that brain-derived neurotrophic factor (BDNF) is involved in the effects of ATX in the brain, there are no studies of BDNF in ADHD patients undergoing treatment with ATX.

Objectives

The aim of this study was to evaluate the possible changes in serum levels of BDNF in adults treated with ATX and its relationship with clinical improvement.

Methods

A total of 54 adults with ADHD (age 33.43?±?8.99 years) without any medical or psychiatric comorbidities were treated with ATX for 3 months; 35 of them completed the protocol. The clinical data for ADHD diagnosis, including Conners’ ADHD Rating Scale and blood samples, were collected at baseline (V1) and at the end of the treatment (V2).

Results

Adults with ADHD who completed ATX treatment for 3 months showed a significant improvement in their clinical symptoms. No significant differences were found in BDNF levels before and after treatment with ATX in the whole group of patients (p?=?0.15). The inattentive subgroup of ATX responders showed a decrease of serum BDNF after 3 months of ATX treatment (p?=?0.05) not present in the combined subtype (p?=?0.82).

Conclusions

These results suggest that BDNF is not directly involved in the neurobiological mechanisms of ATX-induced improvement of clinical symptoms of ADHD. The differences between the combined and inattentive subtypes in serum BDNF changes suggest selective ATX-induced effects in the function of brain circuitry.  相似文献   
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