Synthesis, characterization and study of novel reagents for the detection of saccharides and amino acids

The design of synthetic receptors for the recognition and sensing of saccharides and amino acids is currently a major challenge. This is due to inherent structural similarity and a lack of chromophoric or fluorophoric properties of these compounds. The synthesis and study of novel detection agents for bioactive molecules as well as mechanistic studies are presented herein. The elucidation of the mechanism by which tetraarylboronic acid resorcinarene interact with sugar molecules and promote a solution color change is explored. This vast collaborative study, reveals that DMSO solutions of boronic acid functionalized resorcinarene macrocycles afford visual color changes upon heating or standing and in the presence of saccharides. We found that the solution color is due to macrocycle ring opening and oxidation. Condensation reactions catalyzed by acid formed in situ from DMSO are responsible for xanthene dye formation. As a result of our mechanistic knowledge we were able to design and synthesize a variety of novel receptors. To date two selective receptors for the purpose of saccharide sensing have been synthesized. The first is a rhodamine-derived boronic acid receptor, for use in a novel post-column chromatographic procedure for the detection of saccharides. The second involves the designed and synthesis of a fluorescein-derived phosphonic acid receptor, which interacts with saccharides amino acids and anions via metal complexation. As an extension of our work with saccharides we are exploring the detection of amino acids. We have discovered a highly selective new method for the facile determination of cysteine and homocysteine via a fluorescein dialdehyde derivative. In addition, we have made progress towards the selective, direct colorimetric and fluorometric differentiation between cysteine and homocysteine in the presence of each other despite their great similarity in structure

Centenaire de la Fondation de la Paroisse Sainte Luce 1843-1943

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Breast Cancer Treatment Practices in Elderly Women in a Community Hospital

Background. Elderly women with breast cancer are considered underdiagnosed and undertreated, and this adversely affects their overall survival. Methods. A total of 393 female breast cancer patients aged 70 years and older, diagnosed within the years 1989–1999, were identified from the tumor registry of The Brooklyn Hospital Center. Comparisons between the 3 different subgroups 70–74, 75–79, and 80 years and older were made using the Pearson Chi Square test. Results. Lumpectomy was performed in 42% of all patients, while mastectomy was done in 46% of patients. Adjuvant therapy such as chemotherapy, radiation therapy, and hormonal therapy were done in 12%, 25%, and 38%, respectively. Forty-seven percent of patients with positive lymph nodes received chemotherapy. Eighty-six percent of patients who were estrogen receptor-positive received adjuvant hormonal therapy. Overall five-year survival was only 14% for the ≥80 age group, compared to that of 32% and 35% for the 70–74 and the 75–79 age groups, respectively. Conclusions. Surgery was performed in majority of these patients, about half received lumpectomy, the other half mastectomy. Adjuvant therapies were frequently excluded, with only hormonal therapy being the most commonly used. Overall five-year survival is significantly worse in patients ≥80 years with breast cancer

Intraperitoneally Placed Foley Catheter via Verumontanum Initially Presenting as a Bladder Rupture

Since urethral Foley catheterization is usually easy and safe, serious complications related to this procedure have been rarely reported. Herein, we describe a case of intraperitoneally placed urethral catheter via verumontanum presenting as intraperitoneal bladder perforation in a chronically debilitated elderly patient. A 82-yr-old male patient was admitted with symptoms of hematuria, lower abdominal pain after traumatic Foley catheterization. The retrograde cystography showed findings of intraperitoneal bladder perforation, but emergency laparotomy with intraoperative urethrocystoscopy revealed a tunnel-like false passage extending from the verumontanum into the rectovesical pouch between the posterior wall of the bladder and the anterior wall of the rectum with no bladder injury. The patient was treated with simple closure of the perforated rectovesical pouch and a placement of suprapubic cystostomy tube

Nitrogen cycling and budget in crop rotations as influenced by preceding crops and N fertilization

Non-Peer Reviewe

Optimizing the Productivity and Resiliency of Cropping Systems in the Major Ecozones on the Canadian Prairies

Non-Peer ReviewedAgriculture faces grand challenges of meeting growing food demands and increasing profitability while reducing environmental impacts. A systems approach is required to design and manage cropping systems to meet the goal of agricultural sustainability under climate change. A 4-year rotation study was established in 2018 at seven sites across the Canadian Prairies, including Beaverlodge, Lacombe, and Lethbridge, AB; Melfort, Scott, and Swift Current, SK; and Carman MB. The objective of this project is to develop resilient cropping systems for different ecozones on the Canadian Prairies. This study tested six cropping systems consisting of 1) conventional cropping system (Control), 2) pulse- or oilseed-intensified cropping system (POS), 3) diversified cropping system (DS), 4) market-driven cropping system (MS), 5) high risk and high reward cropping system (HRHRS), and 6) green-manure incorporated soil-health focused cropping system (GMS). Each cropping system varies slightly among experimental sites (ecozones) to mimic local farming practices. Cropping system indicators such as yield, resource use efficiency, soil health, profitability, environmental impact, resiliency, and sustainability will be fully assessed at the end of rotations. The preliminary results from the first 2 years indicated that there was no single cropping system suitable for all study ecozones although POS had an above-average yield and stability among the six cropping systems. We suggest that the optimal cropping system will maximize yield in the high-yielding ecozones and stabilize yields in the low-yielding ecozones. Link to Video Presentation: https://youtu.be/VsK4RNIzaZ

HIV-1 Infection of DC: Evidence for the Acquisition of Virus Particles from Infected T Cells by Antigen Uptake Mechanism

Dendritic cells (DC) play a pivotal role in transmission and dissemination of HIV-1. Earlier studies reported that DC present at the site of infection trap virus particles via DC-SIGN and transfer the virus to the interacting naïve T cells. This prompted us to ask the question whether DC could acquire virus from infected T cells during DC-T cell interaction. To address this, we investigated the likely transfer of virus from HIV-1 infected T cells to DC and the underlying mechanisms involved. Results indicate that DC acquire virus from infected T cells via antigen uptake mechanism and this results in infection of DC with expression of proteins directed by viral DNA. Further studies with HIV-1 lacking the Env protein also resulted in infection of DC. The use of antibodies against DC-SIGN and DC-SIGN-R ruled out a role for receptor in the infection of DC. Additional data show that DC infection is directly correlated with the ability of DC to take up antigen from infected T cells. Overall, these studies provide evidence to suggest that HIV-1, besides infecting immune cells, also utilizes immunological mechanism(s) to acquire and disseminate virus