Preparation of cellulose composites with in situ generated copper nanoparticles using leaf extract and their properties.

In the present work, copper nanoparticles (CuNPs) were in situ generated in cellulose matrix using Ocimum sanctum leaf extract as a reducing agent and aq. CuSO4 solution by diffusion process. Some CuNPs were also formed outside the film in the solution which were separated and viewed by Transmission electron microscope and Scanning electron microscope (SEM). The composite films showed good antibacterial activity against Escherichia coli bacteria when the CuNPs were generated using higher concentrated aq. CuSO4 solutions. The cellulose, matrix and the composite films were characterized by Fourier transform infrared spectroscopic, X-ray diffraction, thermogravimetric analysis and SEM techniques. The tensile strength of the composite films was lower than that of the matrix but still higher than the conventional polymers like polyethylene and polypropylene used for packaging applications. These biodegradable composite films can be considered for packaging and medical applications.

Tuning patterning conditions by co-adsorption of gases: Br2 and H2 on Si(001).

We have studied the co-adsorption of Br2 and H2 on Si(001), and obtained co-adsorption energies and the surface phase diagram as a function of the chemical potential and pressure of the two gases. To do this, we have used density functional theory calculations in combination with ab initio atomistic thermodynamics. Over large ranges of bromine and hydrogen chemical potentials, the favored configuration is found to be either one with only Br atoms adsorbed on the surface, at full coverage, in a (3 × 2) pattern, or a fully H-covered surface in a (2 × 1) structure. However, we also find regions of the phase diagram where there are configurations with either only Br atoms, or Br and H atoms, arranged in a two-atom-wide checkerboard pattern with a (4 × 2) surface unit cell. Most interestingly, we find that by co-adsorbing with H2, we bring this pattern into a region of the phase diagram corresponding to pressures that are significantly higher than those where it is observed with Br2 alone. We also find small regions of the phase diagram with several other interesting patterns.

Neonatal intracerebral hemorrhage: mechanisms, managements, and the outcomes.

Intracerebral hemorrhage is a multifactorial disorder with heterogeneous etiologies and potentially long-term debilitating outcomes. We review all available evidence regarding the current strategies for management of intracerebral hemorrhage. It is clear that prompt detection and treatment does affect the outcome; nevertheless, prevention of intracerebral hemorrhage remains the best strategy.

Can admission S-100beta predict the extent of brain damage in head trauma patients?

BACKGROUND: As has been shown previously, S-100beta levels in serum can be a useful predictor of brain damage after head trauma. This pilot study was designed to investigate whether urine samples, which are much easier to obtain, could be used for the same purpose instead of serum samples. METHODS: Ninety-six consecutive patients admitted with head trauma were recruited in the study. After exclusion of 54 patients, mostly because of significant additional trauma, S-100beta levels were analyzed in serum and urine of 42 patients using a luminometric assay. A range for normal values was established based on samples from ten healthy volunteers. RESULTS: S-100beta serum levels increased proportional to the severity of the head trauma, as had been previously shown by several other groups. In many patients, initial increases in urine S-100beta levels were seen later than in serum, after which the kinetics of S-100beta levels in urine seemed to follow that established for serum levels. S-100beta values in urine were on average about 54% lower in urine than in serum. CONCLUSIONS: S-100beta levels in urine obtained on admission to the hospital are not a good indicator for the extent of brain damage. However, urine S-100beta levels obtained at later time points might be a useful indicator for the development of secondary brain injury.

The incidence trends of primary brain tumors in Saskatchewan from 1970 to 2001.

OBJECTIVE: There has been a paucity of information on the epidemiology of primary brain tumors (BTs) in Canada. This study documents epidemiology of primary BTs in Saskatchewan over three decades to define their current state, changing pattern over years and relative distribution in two geographically defined areas of the province. METHODS: Data on all primary BTs from 1970 to 2001 from the Brain Tumor Registry in Saskatchewan was collected. The aggregate data on primary BTs including the time-series for incidence, age, geographic location and sex were statistically analyzed using SPSS 13. Poisson regression was used to model the incidence as a function of decade of diagnosis and age at the time of diagnosis. RESULTS: The average annual incidence of primary BTs was 11.1 per 100,000 person-years (male 12.5 per 100.000 and female 9.8 per 100.000). Males constituted 54.5% of all these tumors. The age distribution of tumors was bimodal with peaks at 5 years and 65 years. During this time, the incidence of primary BTs has increase predominantly in non-malignant types. No difference was found in the rate of all the diagnosed primary BTs combined, meningioma and lymphoma between the northern part (Regina) and southern part (Saskatoon) of the province. CONCLUSIONS: The incidence of BTs in Saskatchewan is more than previously reported in Canada. There is a temporal trend in increasing incidence of some of the BTs predominantly in the non-malignant types. No spatial difference in the incidence of primary BTs was shown in this province. These data will provide useful information to guide the future studies on BTs changing patterns, possible etiologies and efficient resource allocation for management of these diseases.

Effect of PSC 833, a potent inhibitor of P-glycoprotein, on the growth of astrocytoma cells in vitro.

Malignant astrocytomas have been found to express P-glycoprotein (Pgp, mdr1 gene product). It was hypothesized that in addition to conferring multidrug resistance, Pgp is intimately associated with the development of astrocytomas. Accordingly, we studied the effect of PSC 833 (PSC, Novartis), a potent inhibitor of Pgp, on the growth of Pgp-expressing astrocytoma cells. The results showed that in all the cell lines tested, PSC (10-60 microM) inhibited the growth as well as induced cell death. Cells exposed to PSC exhibited DNA ladder characteristic of apoptosis. PSC-induced cell death could be reversed by Z-VAD-fmk, a general caspase inhibitor, indicating that PSC-induced cell death was characteristic of caspase-mediated apoptosis. These results suggest a novel therapeutic strategy in the treatment of malignant astrocytomas by inhibitors of Pgp.

Structural assignment of 2,6- and 2,7-disubstituted naphthalenes and prediction of (13)C nuclear magnetic resonance chemical shifts: applications of topology and two-dimensional NMR spectroscopy.

Unambiguous assignments of monocarboxymethylnapthalenes isolated as oxidation products of dimethylnaphthalenes by Pseudomonas putida, a bacterial strain, were made using two-dimensional nuclear Overhauser enhancement correlation spectroscopy (NOESEY). The two-dimensional long-range heteronuclear correlation NMR technique was also utilized for the assignment of quaternary carbons in the naphthalene system. In addition, we describe methods for prediction of 13C NMR chemical shifts of 2,6- and 2,7-disubstituted naphthalenes using topological approach. The method involves computation of molecular descriptors from topological representation of molecule, namely Wiener (W) and Szeged (Sz) indices. The results have shown that W and Sz indices can be successfully used for predicting 13C NMR chemical shifts and that Sigma13Cn can be used as a molecular property which in turn can be modeled by both W and Sz indices successfully.