Synthesis, Characterization and Biological Evaluation of Novel (S,E)-11-[2-(Arylmethylene) Hydrazono] Pyrrolo [2,1-c] [1,4] Benzodiazepine Derivatives

Pyrrolo [2,1-c] [1,4] benzodiazepine (PBD) is a class of natural products obtained from various actinomycetes which have both anti-tumor and antibiotic activities and can bind to specific sequences of DNA. PBD-dilactam was initially produced using isatoic anhydride and (L)-proline which was then converted to the PBD-thiolactam using Lawesson\u27s reagent. Reaction of thiolactam with hydrazine in ethanol afforded PBD-11-hydrazinyl. Condensation of 11-hydrazinyl PBD with aldehydes possessing various substitutions was performed to obtain (S,E)-11-[2-(arylmethylene) hydrazono] pyrrolo [2,1-c] [1,4] benzodiazepine derivatives. 1HNMR, 13C-NMR, DEPT, IR, GC-MS and X-ray crystallography were used for the characterization. Inhibition activity of the products were carried out using TEM-1, AmpC and P99 β-lactamases. A minimal inhibition growth of 25% was observed for one of the selected PBDs on cancer cell line. A promising result was observed on preliminary cannabinoid binding activity test on one of the compounds

Bio-synthesised LytC protein kills bacteria and the study of protein dynamics in B. subtilis

For many years, efforts for discovering new antibiotics were mainly focused on the inhibitors of the cell wall synthesis machinery. We tried to find other antibiotics that target the cell wall by making use of the cell wall degradation enzymes, which lyse the cell wall and therefore kill bacteria. LytC is an autolysin from B. subtilis, which is capable of degrading the bacterial cell wall and make it a potential candidate antibiotic. In this dissertation, I cloned B. subtilis lytC gene and over-expressed LytC protein in E. coli. In order to characterize the function of different LytC regions, we designed different constructs of lytC. I used the Gram-negative bacterium E. coli and Gram-positive B. subtilis to test if LytC can degrade the cell wall components when used as an external additive in cell medium. Different constructs of purified LytC protein were used, the results showed that LytC constructs can efficiently and greatly inhibit the growth of E. coli and B. subtilis, yet it is only effective for exponentially growing cells. The cell wall of stationary cells was more resistant to LytC and cell lysis was not observed. I proved that the C-terminal fusion of LytC with a strep-tag can be successfully over-expressed and purified while the N-terminal fusion cannot. Overexpression of LytC leads to a fast drop in OD600 after one hour induction with 0.5 mM IPTG. The construct of LytCF6 only contains the functional region and the purified protein can still function like full length protein, which means the four cell wall binding (CWB) and the „low complexity region“ (LCR) domains are not necessary for LytC activity. I used strep elution buffer with BSA (bovine serum albumin) as control to verify that it is the LytC protein that is responsible for cell growth inhibition. I deleted 22 amino acids from the C-terminus of the functional region, and protein activity of this partially deleted LytCF2R2 was compared with LytCF2 (which has the full length of functional region). As a result, LytCF2R2 lost almost half of the protein activity in comparison to LytCF2. This further demonstrates that LytCF2 contains the functional region and the deletion of it can result in loss of activity. We reviewed the localization and the single molecule trajectories of proteins (MreBCD, Pbp1A, RodZ and PDH complex) in exponentially grown B. subtilis cells. Phosphofructokinase (PfkA), which is a fast moving protein, was used as a control for MreB in the single molecule tracking study. In the protein localization study, we found that MreB, MreC, MreD, RodZ and Pbp1A are localized along the cell membrane and have a similar localization pattern. The results indicate that MreB, MreC, MreD, RodZ and Pbp1A are membrane proteins. We confirmed the phenomenon that MreB forms discontinuous filaments structure underneath the cell membrane, both in B. subtilis and in E. coli. Upon reduction in its expression level, MreB forms patchy and short filament structures in B. subtilis. MreC and MreD also form patchy spots structures besides the membrane staining pattern. From our calculation, two thirds cells have PdhA localized at one cell pole, one third of the cells does not contain PdhA spots. The localization studies of PdhB, PdhC and PfkA showed that they are all uniformly distributed within the cytoplasm of the cell, which indicates they are cytoplasmic proteins. PdhD has two localization patterns, one is the same as chromosome DNA staining, and the other one is uniformly distributed within the cytoplasm. We found single molecules of MreB are composed of two populations. One is the immobile population that forms the filamentous structures. The other one is the mobile population that freely diffuses within the cell. The same conclusions apply to the Pbp1A and PDH subunits proteins, as well as for the MreB colocalized proteins (MreC, MreD and RodZ). The single molecules of the PfkA compose two mobile populations. The fraction and movement speed of MreB mobile single molecules are lower than those of PfkA. We also deduced that MreB is a membrane-associated protein and that PdhC (E2 subunit) is the core of PDH complex from our data analysis, because the fraction and diffusion coefficient of mobile PdhC single molecules are the slowest of the four PDH subunits

Short-term treatment outcomes in human immunodeficiency virus type-1 and hepatitis B virus co-infections

BACKGROUND: Co-infection of HIV with HBV is common in West Africa but little information is available on the effects of HBV on short-term therapy for HIV patients. A 28 day longitudinal study was conducted to examine short-term antiretroviral therapy (ART) outcomes in HIV infected individuals with HBV co-infection. METHODS: Plasma from 18 HIV infected individuals co-infected with HBV and matched controls with only HIV infection were obtained at initiation, and 7 and 28 days after ART. HIV-1 viral load changes were monitored. Clinical and demographic data were also obtained from patient folders, and HIV-1 drug resistance mutation and subtype analysis performed. RESULTS: The presence of HBV co-infection did not significantly affect HIV-1 viral load changes within 7 or 28 days. The CD4(+) counts on the other hand of patients significantly affected the magnitude of HIV-1 viral load decline after 7 days (ρ = −0.441, p = 0.040), while the pre-ART HIV-1 VL (ρ = 0.844, p = <0.001) and sex (U = 19.0, p = 0.020) also determined HIV-1 viral load outcomes after 28 days of ART. Even though the geometric sensitivity score of HIV-1 strains were influenced by the HIV-1 subtypes (U = 56.00; p = 0.036), it was not a confounder for ART outcomes. CONCLUSIONS: There may be the need to consider the confounder effects of sex, pre-ART CD4(+), and pre-ART HIV-1 viral load in the discourse on HIV and HBV co-infection

Mingle, Myrtle (Brown) Autobiography

Autobiography of Myrtle Minglehttps://digitalcommons.pittstate.edu/seks_farm_oral/1038/thumbnail.jp

On Complete Moment Convergence of Weighted Sums for Arrays of Rowwise Negatively Associated Random Variables

The complete moment convergence of weighted sums for arrays of rowwise negatively associated random variables is investigated. Some sufficient conditions for complete moment convergence of weighted sums for arrays of rowwise negatively associated random variables are established. Moreover, the results of Baek et al. (2008), are complemented. As an application, the complete moment convergence of moving average processes based on a negatively associated random sequences is obtained, which improves the result of Li et al. (2004)

Synthesis-Structure-Activity Relationships in Co3O4 Catalyzed CO Oxidation

In this work, a statistical design and analysis platform was used to develop cobalt oxide based oxidation catalysts prepared via one pot metal salt reduction. An emphasis was placed upon understanding the effects of synthesis conditions, such as heating regimen and Co2+ concentration on the metal salt reduction mechanism, the resultant nanomaterial properties (i.e., size, crystal structure, and crystal faceting), and the catalytic activity in CO oxidation. This was accomplished by carrying out XRD, TEM, and FTIR studies on synthesis intermediates and products. Additionally, high-throughput experimentation was employed to study the performance of Co3O4 oxidation catalysts over a wide range of reaction conditions using a 16-channel fixed bed reactor equipped with a parallel infrared imaging system. Specifically, Co3O4 nanomaterials of varying properties were evaluated for their performance as CO oxidation catalysts. Figure-of-merits including light-off temperatures and activation energies were measured and mapped back to the catalyst properties and synthesis conditions. Statistical analysis methods were used to elucidate significant property-activity relationships as well as the design rules relevant in the synthesis of active catalysts. It was found that the degree of grain boundary consolidation and anisotropic growth in fcc and hcp CoO intermediates significantly influenced the catalytic activity. By utilizing the discovered synthesis-structure-activity relationships, CO oxidation light off temperatures were decreased to \u3c90°C

Cochlear Implant Training Model

Currently available training methods for cochlear implant surgeries such as cadavers and imaging systems are expensive and available for a limited number of training sessions. With the goal of decreasing risk factors associated with cochlear implant surgery, our team developed a cochlear implant training model prototype that is designed to provide a trial-and-error, tactile training method for developing force perception levels required to avoid causing damage to the cochlea. This model is designed to utilize a disposable material that ruptures when exposed to critical force levels. A material testing device was developed and utilized to test an assortment of easily accessible, thin materials that could be used by the training model. Further testing is still required before selecting the final material for the training model. An overview of potential material selection methods is given to improve future material testing results