苯基脒/碘化亚铜催化碘代芳烃与二芳胺的反应

N 烷(芳)基苯甲酰胺与氯化亚砜作用后,在三乙胺存在下与芳伯胺或脂肪伯胺反应,方便、高产率地得到了6个N,N′ 烷基或芳基苯甲脒;然后将其作为配体应用于铜催化的碘苯与二苯胺的偶联反应中,该类配体显示出了良好的活性,其中N 苯基 N′ 叔丁基苯甲脒(L6)的活性最高,产率达到96%;不同取代的碘代芳烃和含有吸电子或供电子基团的二苯胺用这一催化体系进行底物扩展,均能以很高的产率得到偶联产物。将这一催化体系应用于OLED(Organic Light Emitting Diode)的空穴传输材料N,N,N′,N′ 四苯基联苯二胺(TPB)及其溴代的衍生物的合成中,分别以77%和70%的产率得到目标产物。     

The Impact of the COVID-19 Pandemic on Food Distribution at Emergency Food Assistance Organizations in the Southwestern United States: A Qualitative Investigation

This study aimed to identify changes in food distribution operations at emergency food assistance organizations (EFAOs) during the COVID-19 pandemic. EFAOs across the Houston metro area, TX (human service centers and food pantries) as well as the Houston Food Bank (HFB) participated in the qualitative study. Data were collected via individual semi-structured interviews and focus group (December 2020–February 2021), and coded using semi-structured thematic analysis. Categories were pre-identified based on the interview questions. Direct quotes supported subcategories. Directors from 18 EFAOs were interviewed; 8 HFB leadership staff participated in a focus group. Four major categories of change due to COVID-19 included new safety measures, changes in food distribution process, changes in volunteerism and staffing, and changes in amounts of food distributed. This study helps identify susceptibilities in EFAOs’ food distribution chain should be addressed to manage future emergency food insecurity crises more effectively. An understanding of the changes/challenges incurred by EFAOs during the COVID-19 pandemic can inform policymakers to ensure local food distribution organizations are prepared to fill the needs during future a crisis of food insecurity.     

Buccal Mucosa Assessed by Ultrasonography in Healthy Adults: Methodology and Determination of Normal Appearance

The aim of the work described here was to compare intra-oral and transcutaneous ultrasonography (US) scanning and to determine the normal values of buccal mucosa thickness and echogenicity. A total of 190 volunteers underwent US examination of the buccal mucosa. The thickness of the buccal epithelial layer was recorded in 19 subjects via both intra-oral and transcutaneous methods. Overall, 171 healthy adults were examined through intra-oral US. Buccal epithelial layer measurement was unreliable via the transcutaneous method (p?=?0.001). The mean time required for visualizing the buccal mucosa was 75 and 171s with intra-oral and transcutaneous US, respectively (p < 0.001). The thickness of the buccal epithelial layers significantly differed with age and sex (p < 0.001), and was positively correlated with height, weight and body surface area. Intra-oral US was proposed as a conventional method for examination of the buccal mucosa. Normal buccal epithelial thickness in adults is associated with age, sex, height, weight and body surface area.     

Nutrient Density and the Cost of Vegetables from Elementary School Lunches

Vegetables are the major source of the dietary fiber, magnesium, potassium, and vitamins A and C that are crucial in the diets of children. This study assessed the nutrient content of vegetables offered through the National School Lunch Program and examined the relation between the overall nutrient density of vegetable subgroups and the costs of nutrients offered and wasted before and after the changes in school meal standards. Using data collected from 3 elementary schools before and after the changes in school meal standards, we found that vegetable plate waste increased from 52% to 58%. Plate waste for starchy vegetables, exclusive of potatoes, was relatively high compared with other subgroups; however, plate waste for white potatoes was the lowest among any type of vegetable. Energy density; cost per 100 g, per serving, and per 100 kcal; and percentage daily value were calculated and used to estimate nutrient density value and nutrient density per dollar. Cost per 100 kcal was highest for red/orange vegetables followed by dark green vegetables; however, nutrient density for red/orange vegetables was the highest in the group and provided the most nutrients per dollar compared with other subgroups. Given that many vegetables are less energy dense, measuring vegetable costs per 100 g and per serving by accounting for nutrient density perhaps is a better way of calculating the cost of vegetables in school meals.     

Epigenetic inactivation of TRAIL decoy receptors at 8p12‐21.3 commonly deleted region confers sensitivity to Apo2L/trail‐Cisplatin combination therapy in cervical cancer

Multiple chromosomal regions are affected by deletions in cervical cancer (CC) genomes, but their consequence and target gene involvement remains unknown. Our single nucleotide polymorphism (SNP) array identified 8p copy number losses localized to an 8.4 Mb minimal deleted region (MDR) in 36% of CC. The 8p MDR was associated with tumor size, treatment outcome, and with multiple HPV infections. Genetic, epigenetic, and expression analyses of candidate genes at MDR identified promoter hypermethylation and/or inactivation of decoy receptors TNFRSF10C and TNFRSF10D in the majority of CC patients. TNFRSF10C methylation was also detected in precancerous lesions suggesting that this change is an early event in cervical tumorigenesis. We further demonstrate here that CC cell lines exhibiting downregulated expression of TNFRSF10C and/or TNFRSF10D effectively respond to TRAIL‐induced apoptosis and this affect was synergistic in combination with DNA damaging chemotherapeutic drugs. We show that the CC cell lines harboring epigenetic inactivation of TRAIL decoy receptors effectively activate downstream caspases suggesting a critical role of inactivation of these genes in efficient execution of extrinsic apoptotic pathway and therapy response. Therefore, these findings shed new light on the role of genetic/epigenetic defects in TRAIL decoy receptor genes in the pathogenesis of CC and provide an opportunity to explore strategies to test decoy receptor gene inactivation as a biomarker of response to Apo2L/TRAIL‐combination therapy. © 2015 Wiley Periodicals, Inc.     

Complications and diagnostic difficulties arising from biliary self-expanding metal stent insertion before definitive histological diagnosis

Background: Self‐expanding metal bile duct stents provide good palliation for inoperable malignant disease. However, problems may arise if metal stents are inserted before definitive histological diagnosis. The aim of this study was to evaluate the outcome of such patients. Methods: A retrospective case note review was conducted of patients referred to a tertiary pancreaticobiliary center between 1992 and 2004 in whom a metal bile duct stent was inserted for presumed unresectable malignant disease before definitive histological diagnosis. Results: There were 21 patients identified. Final diagnoses were: group 1, benign disease (n = 3); group 2, resectable malignancy (n = 2); group 3, unresectable malignancy (n = 12); and group 4, diagnosis remains uncertain (n = 4). During a follow‐up of 22, 38 and 111 months, the patients in group 1 had one, eight and five episodes of stent occlusion. In group 2, both patients underwent pancreaticoduodenectomy for ampullary carcinoma, 2 and 6 months after presentation. In group 3, the median time to a confirmed malignant diagnosis was 2 months (range 1–27 months). In group 4, a median of two biopsies (range 1–4) were negative for malignancy, during a median follow up of 13 months (range 3–46). Overall in eight patients, the metal stents caused artifacts on computed tomography and/or were associated with tissue in‐growth making the differentiation between benign and malignant disease difficult. Conclusion: These cases indicate that metal bile duct stent insertion before definitive histological diagnosis can be problematic. A proportion of cases will have benign strictures and in others the confirmation of malignancy may be made more difficult.     

Synergistic apoptotic response between valproic acid and fludarabine in chronic lymphocytic leukaemia (CLL) cells involves the lysosomal protease cathepsin B

Fludarabine, a nucleoside analogue, is commonly used in combination with other agents for the treatment of chronic lymphocytic leukaemia (CLL). In previous studies, valproic acid (VPA), an inhibitor of histone deacetylases, combined with fludarabine to synergistically increase apoptotic cell death in CLL cells. In the present study, we found that the combination of fludarabine and VPA decreases the level of the anti-apoptotic proteins Mcl-1 and XIAP in primary CLL cells. Treatment with fludarabine alone, or in combination with VPA, led to the loss of lysosome integrity, and chemical inhibition of the lysosomal protease cathepsin B, using CA074-Me, was sufficient to reduce apoptosis. VPA treatment increased cathepsin B levels and activities in primary CLL cells, thereby priming CLL cells for lysosome-mediated cell death. Six previously treated patients with relapsed CLL were treated with VPA, followed by VPA/fludarabine combination. The combined therapy resulted in reduced lymphocyte count in five out of six and reduced lymph node sizes in four out of six patients. In vivo VPA treatment increased histone-3 acetylation and cathepsin B expression levels. Thus, the synergistic apoptotic response with VPA and fludarabine in CLL is mediated by cathepsin B activation leading to a decrease in the anti-apoptotic proteins.