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581.
SHP-2, a nonreceptor protein tyrosine phosphatase encoded by the PTPN11 gene, mediates cell signaling by growth factors and cytokines via the RAS/MAP kinase pathway. Somatic mutations in PTPN11 gene account for approximately 18% of juvenile myelomonocytic leukemia (JMML) patients. Moreover, SHP-2 mutations leading to continuously active enzyme were found in more than 50% of Noonan syndrome patients and are considered to be responsible for the high tendency of these patients to juvenile leukemias and other cancer types. Recently SHP-2 became a new drug target, but till now little has been done in this field. In the present study, 17 2-thiazolylimino/heteroarylimino-5-arylidene-4-thiazolidinones divided into three series of derivatives bearing thiazole-, benzo[d]thiazole-, and benzo[d]isothizole rings were tested for SHP-2 inhibitory activity. Most of the compounds were good SHP-2 inhibitors. Benzo[d]thiazole derivatives exhibited the best inhibitory action. Docking studies revealed that hydrophobic interactions and hydrogen bond formation stabilize enzyme-inhibitor complex.  相似文献   
582.
PurposeTo compare rates of regional recurrence (RR) and overall survival (OS) between a pooled set of 1400 patients treated on the American Society of Breast Surgeons MammoSite (Hologic, Inc., Bedford, MA) Registry Trial to a cohort of 3600 patients treated with whole breast irradiation (WBI).Methods and MaterialsA total of 1440 women underwent accelerated partial breast irradiation (APBI) between 2002 and 2004 as part of the American Society of Breast Surgeons Registry Trial and a total of 3593 patients who received WBI were evaluated from the Surveillance Epidemiology and End Results database with treatment received between 1980 and 2009. A matched-pair analysis was performed based on age, receipt of hormonal therapy, chemotherapy, nodal status, and tumor size (1051 patients per arm). Rates of RR and OS were then analyzed for each group.ResultsAfter the match, no differences in patient characteristics were noted when tumor size was evaluated as a continuous variable. Rates of RR and OS were similar between the WBI and APBI groups. A Cox regression model found no difference between WBI and APBI with regard to RR; however, OS was improved in the APBI cohort (hazard ratio 0.008, p < 0.0001).ConclusionsWith one of the largest patient populations to date comparing WBI and APBI, no difference in RR or OS was noted between WBI and APBI treatment. Until the publication of prospective Phase III trials, these data support the continued use of APBI on protocol and off protocol in appropriately selected patients.  相似文献   
583.

Background

Nipple-sparing mastectomy (NSM) is increasingly used in women with breast cancer who are not eligible for conservative surgery, but extensive outcome data are lacking and indications have not been established.

Objective

The aim of this study was to assess the oncological outcomes of NSM in a large series of patients with invasive or in situ breast cancer treated at a single center.

Methods

We analyzed 1989 consecutive women who had an NSM in 2003–2011, for invasive (1711 patients) or in situ cancer (278 patients) at the European Institute of Oncology, Italy, and followed-up to December 2016. Endpoints were local recurrences, recurrences in the nipple-areola complex (NAC), NAC necrosis, and overall survival (OS).

Results

After a median follow-up of 94 months (interquartile range 70–117), 91/1711 (5.3%) patients with invasive cancer had local recurrence (4.8% invasive disease, 0.5% in situ disease), and 11/278 (4.0%) patients with in situ disease had local recurrence (1.8% invasive disease, 2.2% in situ disease). Thirty-six (1.8%) patients had NAC recurrence, 9 with in situ disease (4 invasive and 5 in situ recurrences), and 27 with invasive disease (18 invasive and 9 in situ recurrences). NAC loss for necrosis occurred in 66 (3.3%) patients. There were 131 (6.6%) deaths, 109 (5.5%) as a result of breast cancer. OS at 5 years was 96.1% in women with invasive cancer and 99.2% in women with in situ disease.

Conclusions

The findings in this large series, with a median follow-up of nearly 8 years, indicate that NSM is oncologically safe for selected patients. The rate of NAC loss was acceptably low.
  相似文献   
584.
We established clonality relationships between invasive ipsilateral breast failures (IBFs; local recurrences) and initial invasive carcinomas using a molecular polymerase chain reaction loss of heterozygosity (LOH) assay for 26 patients treated with breast-conserving therapy for invasive carcinoma with no distant metastases (DMs) before the IBE LOH was +/- 50% allelic loss. Eighteen IBFs (69%) were related clonally to initial carcinomas; 8 (31%) were clonally distinct, second primary carcinomas. IBFs and initial invasive carcinomas were morphologically similar in 6 (75%) of 8 clonally different cases. Clinical IBF classification and molecular assay results differed in 11 cases (42%). The mean intervals to IBF were 4.7 years in related and 8.7 years in different cases (P = .013). In 6 patients, DMs developed; 5 had related IBFs. In related IBF cases, the mean increase in fractional allelic loss (FAL) of IBFs associated with DMs was 18.9% compared with 7.6% in cases unassociated with DMs (P = .004). Molecular assays can accurately establish the clonality of most IBFs. Morphologic comparison and clinical IBF classification are unreliable methods of determining clonality. Clonally related IBFs occurred sooner than clonally different IBFs. Patients with clonally related IBFs are the main pool in which DMs occur Not all clonally related IBFs have the same DM association; those with large FAL gains were associated with DMs. Molecular clonality assays may provide a reliable means of identifying patients who might benefit from systemic chemotherapy at the time of IBF.  相似文献   
585.
OBJECTIVES: To assess the serum and lower respiratory tract tobramycin concentrations (C(T)) produced by a single dose of tobramycin for inhalation delivered by a nebulizer and a compressor in patients with cystic fibrosis (CF) 6 months to 6 years of age. STUDY DESIGN: We performed a dose escalation study of serum C(T) measured before and 0.5, 1, 2, and 4 hours after a single dose of inhaled tobramycin, either 180 mg (10 patients) or 300 mg (19 patients). In a separate group of 12 patients, epithelial lining fluid (ELF) C(T) was measured by bronchoalveolar lavage 30 to 45 minutes after a 300-mg dose. RESULTS: A 180-mg dose of inhaled tobramycin produced a mean peak serum C(T) of 0.5 microg/mL (SD 0.4; range, <0.2 to 1.4 microg/mL). A 300-mg dose produced a mean peak serum C(T) of 0.6 microg/mL (SD 0.5; range, <0.2 to 1.2 microg/mL). These peak values are well below the accepted maximum trough concentration with parenteral dosing (2 microg/mL). The target ELF C(T) was 20 microg/mL, 10-fold greater than the minimal inhibitory concentration for most Pseudomonas aeruginosa isolates from very young patients with CF (2 microg/mL). Mean ELF C(T) was 90 microg/mL (SD 54; range, 16 to 204 microg/mL) and exceeded the target concentration in 11 patients. CONCLUSION: In patients with CF ages 6 months to 6 years, a single 300-mg dose of inhaled tobramycin appears to produce safe peak serum concentrations and drug concentrations in the bactericidal range in the lower respiratory tract.  相似文献   
586.
587.
Androstenol is a steroidal compound belonging to the group of odorous 16-androstenes, first isolated from boar testes and also found in humans. Androstenol has pheromone-like properties in both animals and humans, but the molecular targets of its pheromonal activity are unknown. Androstenol is structurally similar to endogenous A-ring reduced neurosteroids that act as positive modulators of GABA(A) receptors. Here we show that androstenol has neurosteroid-like activity as a GABA(A) receptor modulator. In whole-cell recordings from cerebellar granule cells, androstenol (but not its 3beta-epimer) caused a concentration-dependent enhancement of GABA-activated currents (EC(50), 0.4 microM in cultures; 1.4 microM in slices) and prolonged the duration of spontaneous and miniature inhibitory postsynaptic currents. Androstenol (0.1-1 microM) also potentiated the amplitude of GABA-activated currents in human embryonic kidney 293 cells transfected with recombinant alpha1beta2gamma2 and alpha2beta2gamma2 GABA(A) receptors and, at high concentrations (10-300 microM), directly activated currents in these cells. Systemic administration of androstenol (30-50 mg/kg) caused anxiolytic-like effects in mice in the open-field test and elevated zero-maze and antidepressant-like effects in the forced swim test (5-10 mg/kg). Androstenol, but not its 3beta-epimer, conferred seizure protection in the 6-Hz electroshock and pentylenetetrazol models (ED(50) values, 21.9 and 48.9 mg/kg, respectively). The various actions of androstenol in the whole-animal models are consistent with its activity as a GABA(A) receptor modulator. GABA(A) receptors could represent a target for androstenol as a pheromone, for which it is well suited because of high volatility and lipophilicity, or as a conventional hormonal neurosteroid.  相似文献   
588.
Acute Mesenteric Ischemia (AMI) is a rare life-threatening entity caused by sudden interruption of the blood supply to a segment of the bowel due to impairment of mesenteric arterial blood flow or venous drainage. Clinical presentation varies according to the time course of vascular occlusion. Contrast-enhanced Computed Tomography (CT) of the abdomen represents the main diagnostic test for AMI diagnosis, enabling fast and excellent evaluation of the intestine, mesenteric vasculature, and other ancillary characteristics of AMI. Typical CT findings of AMI include paralytic ileus, decreased or absent bowel wall contrast-enhancement, pneumatosis intestinalis, and porto-mesenteric venous gas. We hereby report a case of an 89-year-old man presenting with AMI due to Superior Mesenteric Artery (SMA) thrombotic occlusion following endovascular stenting superficial femoral arteries. Typical findings were observed on abdominal CT imaging, yet associated with the presence of gas exclusively in the SMA district, without any involvement of the porto-mesenteric venous system. Different imaging features and pitfalls can help radiologists to accurately diagnose AMI, especially when irreversible bowel damage is about to occur. Therefore, radiologists and emergency physicians should be aware of the unusual association between gas in the SMA arterial district and AMI, even in the absence of porto-mesenteric venous system involvement, in order to urge prompt surgical consultation when observed.  相似文献   
589.
Fitz-Hugh-Curtis Syndrome is a rare disorder manifesting as a complication associated with Pelvic Inflammatory Disease. The initial presentation generally consists of concomitant right upper quadrant and lower abdominal pain. This syndrome is characterized by inflammation of the peritoneum with the involvement of hepatic capsule and the tissues surrounding the liver. Intrahepatic involvement is rare and not yet well investigated. An accurate interpretation of Computed Tomography and Magnetic Resonance Imaging findings is missing in the literature. This report presents a case of Fitz-Hugh-Curtis Syndrome in which Computed Tomography and Magnetic Resonance Imaging showed a region of heterogeneously decreased enhancement and abnormal signal intensity within the liver mimicking a lesion.  相似文献   
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