Various studies have been conducted using hydroxyapatite (HA) to deliver therapeutic drugs over a long period of time. However, the rate of drug release from ceramics varies tremendously. Thus a ...study was designed to observe the effect of particle size, pressure, drug ratio, and the addition of a zinc stearate binder on the release of BSA from ceramics. Samples were collected every two hours for a 12 hour period. Three particle sizes were used in the study (< 38, 45-63, and 63-75 microns). Variations in particle size did not influence the release of BSA. Ceramics compressed at a pressure of 150 Mpa delivered more protein than pressures of 300 MPa, 450 MPa, and 900 MPa. Drug to ceramic ratio had the most significant effect. A ratio of 1:25 BSA to HA delivered the protein quickly whereas the 1:100 BSA to HA delivered BSA to HA delivered BSA slowly and in zero order kinetics. The addition of the zinc binder improved the quality of the composite and decreased the release rate of protein delivery when present in 5% or less of the total ceramic weight. HA ceramics can be used to deliver proteins at different rates by varying compression pressure and drug to HA ratio.
Photon emission from germinating gram seeds at various stages of growth exhibits a definite pattern. The pattern of emission changes when a seed is disrupted by physical processes, e.g. mechanical ...crushing, cooling or heating. The disrupted seeds do not grow. The change in the biological order responsible for seed growth and the observed changes in the pattern of photo emission suggest a link between the macroscopic spatio-temporal organization and metabolic processes.
Interleukin-2 (IL-2) is a potentially effective cytokine to be used for cancer treatment. Since keeping IL-2 doses at a low, continuous level is important to avoid side effects which accompany high ...IL-2 doses, a ceramic which release IL-2 could prove to be a beneficial method of drug delivery for cancer patients 1. In vitro studies were performed to determine the optimal hydroxyapatite (HA) to IL-2 ratio for continuous release of IL-2 from HA using both a matrix and insert ceramic pellet. In the matrix pellet experiment, HA to IL-2 ratios of 25:1, 50:1 and 100:1 were tested by compressing a homogenous mixture of each variable in triplicate and placing each ceramic in 2.5 mL simulated body fluid (SBF) at 37 degrees C. The fluid was collected and replaced for each ceramic every two hours for 12 hours and at 24 hours. The collected fluid was then assayed for IL-2 content. Pellets consisting of 25:1 ceramic to drug ratio delivered almost the entire amount of IL-2 at the fastest rate. Composites of 100:1 IL-2 to HA delivered the least amount of IL-2 at the slowest rate. Release of IL-2 from the 50:1 ratio pellets was intermediate with respect to speed and amount of delivery. In the insert pellet experiment, similar laboratory procedures were used to show that 100:1 ratio insert pellets delivered IL-2 at a slower rate and in lesser amounts than 50:1 ratio insert pellets. Results of this study show that HA can deliver IL-2 at different rates by varying the ratio of HA to IL-2 in both matrix and insert ceramic pellets.
Sugar-mill wastewaters have potential to support microalgal biomass production for use as a biofuel feedstock (lipid source). Growth kinetics, light dynamics, and lipid production in ...multispecies-microalgae cultures collected from a sugar-mill pond are reported
in this paper. Lipid content of the microalgae collected from the pond water was 14.5 % (w/w). Culturing the same microalgae in a photobioreactor on the pond wastewater supplemented with Gillard’s F/2 and CO2, and irradiated with 151 to 337 μmol s–1 m–2 artificial
light produced cells with lipid contents of 11 % (w/w) at 25 °C, 35 % (w/w) at 31 °C, and 28.6 % (w/w) at 33 °C. The maximum specific growth rates (μmax) at 25 °C, 31 °C, and 33 °C were 0.64 d–1, 2.5 d–1, and 2.7 d–1, respectively. Under these conditions, cell densities as high as 1020 g cell dry mass (CDM) m–3 were recorded. Total scalar irradiance attenuation coefficient (k0) was 0.275 m–1 in clear water and 30.5 m–1 in the dense culture. The attenuation coefficient of irradiance due to biomass (kB) was found to be a linear function of cell concentration in this work.
During the last 11 years, 101 patients of Wilms tumor were seen. Of these, 13 patients had metastatic disease at onset while 24 patients presented with relapse at a latter date. Seven patients have ...been cured, all had favourable histology. The risk factors associated with relapse were found to be unfavourable histology, lymph node involvement, age more than 6 years, diffuse spill, capsular and vascular invasion, and aneuploidy. Of the 18 patients who had relapsed, 14 were found to be aneuploid. Judicious use of various therapeutic options like radiotherapy to metastatic sites, second look surgery, resection of pulmonary metastasis and use of cis-platinum, VP-16 and Ifosfamide as "alternative chemotherapy protocols" were used to achieve cure in these advance cases.
Aims
Marfan syndrome (MFS) is a connective tissue disorder caused by mutations in the fibrillin-1 (FBN1) gene. It has been observed that FBN1 deficient mice have reduced left ventricular (LV) ...systolic function which is correlated to increased transforming growth factor-β activity. This study aimed to ascertain LV functional abnormalities in MFS patients using M-mode and tissue Doppler imaging (TDI).
Methods and results
In 66 (15-58 years) MFS patients and 61 normal controls, ejection fraction (EF) was evaluated by Simpson's biplane method. Atrioventricular plane displacement (AVPD) obtained from five mitral annular regions was also assessed using M-mode and TDI techniques. To overcome limitations associated with conventional M-mode echocardiography, anatomical and colour anatomical M-mode were also utilized.
Ejection fraction was significantly reduced in MFS patients when compared to controls (66.3 ± 0.74 vs. 71.9 ± 0.56, P < 0.001), although it was within the normal range. M-mode and TDI AVPD measurements obtained from lateral, septal, inferior, anterior and posterior mitral annular regions were also significantly reduced in MFS patients in comparison to controls (P <0.001, for all measurements).
Conclusion
Left ventricular long-axis systolic function is significantly reduced in MFS patients. This data suggests that LV function should be monitored in MFS and appropriate treatment applied if necessary.
Aims
The right ventricle (RV) ejects the same volume of blood at the same rate as the left ventricle (LV). Mild LV dysfunction has been demonstrated in Marfan syndrome (MFS). However, little ...attention has been paid to the functioning of the RV. The aim of this study was to assess RV function in unoperated adult MFS patients.
Methods and results
In 66 unoperated (15-58 years) MFS patients and 61 controls, rate of pressure rise (dp/dt) in RV, and tricuspid annular motion (TAM) were studied using conventional echocardiography and tissue Doppler imaging (TDI). When compared with controls, MFS patients showed impaired RV systolic function as expressed by a reduced dp/dt, TAM obtained by M-mode echocardiography, and peak TDI systolic velocities at the basal lateral wall (745.36 ± 37.85 vs. 1103.30 ± 27.30 mmHg, P < 0.001; 2.2 ± 0.05 vs. 2.5 ± 0.05 cm, P < 0.001; and 0.13 ± 0.002 vs. 0.16 ± 0.002 m/s, P < 0.001, respectively).
Conclusion
This study demonstrated a primary impairment of RV systolic function in MFS. This is the first study to report RV dysfunction in MFS. Such data could prove valuable during the peri-operative and long-term medical management of MFS patients.
The many complications and risks of autograft and allograft bone have resulted in the search for an effective synthetic bone graft substitute 1,2. The purpose of this study is to determine the ...effectiveness of ZCAP (zinc calcium phosphate) ceramic organic acid composite as an osteoconductive agent, including its possible benefits or risks for patients requiring bone grafting. A solid control model has been developed with an isolated mid-diaphyseal femur fracture immobilized by intramedullary threaded K-wire fixation. Two trials were performed in which two formulations of ZCAP composite ceramic were tested. The first, used in eighteen rats will be referred to as ZCAP1, the second, used in six rats will be referred to as ZCAP2. In the first trial rat femurs were augmented with 0.1 g ZCAP1 composite ceramic which varied in pore size. One pore size performed better than the others, so that pore size along with some minor changes in the composite design to increase resistance to the stresses inherent in our weight bearing model resulted in ZCAP2, which was tested in the second trial. The rats were sacrificed at ten weeks, during which time all rats remained viable. Blood work was done prior to sacrifice and radiography was done on all femurs. After sacrifice, gross morphological exam showed filling of the defect. Sections of the femurs from each group were analyzed by decalcified histological examination, electron microscopy, and tensile strength testing. The ZCAP composite ceramic had no significant effect on blood chemistry or body weight. Initial histological studies were consistent with endochondral ossification which was confirmed by electron microscopy.
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