Novel Nd-N/TiO2 Nanoparticles for Photocatalytic and Antioxidant Applications Using Hydrothermal Approach.

In this study, photocatalysis was employed to degrade a wastewater pollutant (AB-29 dye) under visible light irradiation. For this purpose, nitrogen (N)- and neodymium (Nd)-doped TiO2 nanoparticles were prepared using the simple hydrothermal method. X-ray diffraction (XRD) revealed an anatase phase structure of the Nd-N/TiO2 photocatalyst, whereas properties including the surface morphology, chemical states/electronics structure and optical structure were determined using transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and UV-visible (UV-vis.) and photoluminescence (PL) spectroscopies. Photocatalytic testing of the prepared nanomaterials was performed to remove acid blue-29 (AB-29) dye under visible-light exposure. The prepared Nd-N/TiO2 nanoparticles demonstrated a superior photocatalytic activity and the decolorization efficiency was about 92% after visible-light illumination for 1 h and 20 min, while N/TiO2, Nd/TiO2 and TiO2 only showed a 67%, 43% and 31% decolorization efficiency, respectively. The enhanced photocatalytic activity of the Nd-N/TiO2 photocatalyst was due to a decrease in the electron/hole's recombination and the increased absorption of TiO2 in the visible range. The reusability results showed that the average photocatalytic activity decrease for all the samples was only about 16% after five consecutive cycles, indicating a good stability of the prepared nanomaterials. Moreover, the radical scavenging activity of the prepared nanomaterials was evaluated using the DPPH method. The novel Nd-N/TiO2 exhibited a higher antioxidant activity compared to all the other samples.

Adult-onset epilepsy associated with dysembryoplastic neuroepithelial tumors.

RATIONALE: Dysembryoplastic neuroepithelial tumors (DNET) are benign, localized lesions that typically cause localization-related epilepsy of childhood onset. Although excellent seizure outcomes are expected following surgical resection of focal, benign lesions, reports in pediatric epilepsy series suggest that this may not be the case with DNETs, which may exhibit complex and often multifocal epileptogenesis. We report the characteristics and surgical outcome of an adult- and childhood-onset cohort with this condition. METHODS: Retrospective cohort of 23 patients seen at two major epilepsy centers, with localization-related epilepsy associated with histopathologically demonstrated DNETs. We assessed clinical, electrographic and surgical outcome features in patients with adult- and childhood-onset epilepsy. We were particularly interested in the level of congruence of EEG and MRI data and the need for intracranial recordings. We evaluated seizure outcomes at last follow-up. RESULTS: The mean age was 33.3 years (range: 5-56 years). Ten patients had adult-onset epilepsy. Thirteen patients (57%) had simple partial, 21 (91%) had complex partial, 16 (70%) had secondarily generalized seizures and 5 patients had only simple partial seizures. Status epilepticus did not occur. Non-enhancing lesions on MRI were located in the temporal lobe in 17 patients, the frontal lobe in 3 patients and the parietal/occipital region in 2 patients. One patient had a DNET that involved both frontal and temporal areas. Ictal scalp EEG and MRI were congruent in 17 patients (74%). Eleven patients (48%) underwent lesionectomies, while the rest required some resection of extralesional cortex as well. Five patients required intracranial EEG. There was no association with cortical dysplasia. Seventeen patients (74%) had an Engel class 1 outcome, in a follow-up period that ranging from 5 to 98 months. CONCLUSIONS: We found no difference in outcomes between adult- and childhood-onset cases. Although epileptogenicity was complex, congruence between electro-clinical and neuroimaging studies was high and allowed good surgical outcomes at 1 year of follow-up.

Contrast-induced nephrotoxicity in renal allograft recipients.

BACKGROUND: Intravenous administration of radiographic contrast agents is an important cause of acute renal failure, accounting for one third of the cases of hospital-acquired acute renal failure in patients with native kidneys. The safety of intravenous contrast has not been studied in renal allograft recipients since the availability of cyclosporine as a maintenance immunosuppressive therapy. As patients with renal transplantation may be at a higher risk of contrast-induced nephrotoxicity (CIN) due to concomitant use of cyclosporine and higher prevalence of diabetes and renal insufficiency, we retrospectively studied development of CIN in these patients. PATIENTS AND METHODS: We identified 44 patients (1988 1997) with functioning renal allograft who underwent different intravenous or intraarterial contrast studies (ICS). Pre- and post-ICS renal function tests were done in 35 of these patients. The following were the various ICS done in these patients: coronary angiogram (6), CT scan with intravenous contrast ( 11), angiogram for evaluation of peripheral vascular disease (11), allograft angiogram with angioplasty (5), pulmonary angiogram (1) and intravenous pyelogram (1). The mean age of the patients was 42 +/- 2.1 years and the mean serum creatinine was 2.3 +/- 0.25 mg/dl (mean +/- SEM). Fourty percent of patients (14 of 35) had diabetes, and 25.7% (9 of 35) had chronic rejection. Ninety four percent (33 of 35) of the patients were taking cyclosporine at the time of ICS. RESULTS: Nine patients had > or = 25% increase in serum creatinine from baseline after ICS. Two of these patients were excluded from the analysis as renal functions in these patients had deteriorated prior to ICS and renal failure was attributed to sepsis. Of the remaining 7 patients, 5 had diabetes and 2 had chronic rejection. Only 4 of these 7 patients with CIN received prophylaxis (I/V hydration) prior to ICS. The baseline serum creatinines were not different in patients who had no change in renal function to those who developed CIN (1.97 +/- 0.20 vs 1.54 +/- 0.17 mg/dl, p = 1.5, mean +/- SEM). More than 50% increase in baseline serum creatinine was seen in only 3 of these 7 patients, 2 of these patients had diabetes and third had chronic rejection and congestive heart failure. None of these patients received prophylaxis for CIN. Dialysis was not required in any patient. Three patients also had a > 25% decrease in baseline serum creatinine after ICS, and all of them had allograft angiography with angioplasty for renal artery stenosis. CONCLUSION: In our retrospective study, the incidence of CIN in renal allograft recipients applying a broader classification of > or = 25% increase in baseline serum creatinine was 21.2% (7 of 33 patients). The incidence of CIN was lower 15.3% (4 of 26) in patients who received intravenous hydration compared to 42.8% (3 of 7) in patients who received no prophylaxis prior to ICS.

Effect of hemodialysis and antiretroviral therapy on plasma viral load in HIV-1 infected hemodialysis patients.

BACKGROUND: Plasma viral load has become an important test in predicting the progress of HIV-1 infected patients. The higher the viral load the faster is the progression to AIDS. As HIV-1 infected hemodialysis (HD) patients have higher mortality and morbidity than HIV-1 infected non-dialysis patients, and as all the blood tests in the HD patients are drawn during HD, we measured the effect of HD and antiretroviral therapy on viral load in HIV-1 infected HD patients. PATIENTS AND METHODS: We measured plasma viral load pre-dialysis and post-dialysis in 10 HIV-1 infected HD patients. The viral load was measured using an in vitro quantitative nucleic acid amplification test. We also compared viral load in 8 HIV-1 infected HD patients on one antiretroviral drug with 8 HIV-1 patients on two (6) or three (2) antiretroviral drugs. RESULTS: There was a small reduction in plasma viral load postdialysis in all HIV-1 infected HD patients (45% +/- 5.4, 0.3 log +/- 0.05, p < 0.0004). However, HIV-1 RNA could not be detected in the ultrafiltrate. The patients who were on two or three antiretroviral drugs had lower viral load (8915 +/- 3702 vs. 351440 +/- 101237, p < 0.004) and higher CD4 count (355 +/- 81 vs 82 +/- 39, p < 0.009) than patients on only one antiretroviral drug. CONCLUSION: We conclude that there is a small reduction in plasma viral load in HIV-1 infected hemodialysis patients post-dialysis. As no viral RNA could be detected in the ultrafiltrate, the reduction could be due to nonspecific adsorption of the viral RNA to the dialysis membrane. HIV-1 infected hemodialysis patients who are on two or three antiretroviral drugs had significantly lower viral load and higher CD4 count than patients on only single antiretroviral drug. Therefore a single antiretroviral drug should not be used in treating HIV-1 infected HD patients.

Isolation and identification of mycobacteria from cattle slaughtered in Pakistan.

Specimens of lung, liver and mesenteric lymph node from cows and buffaloes slaughtered in the Lahore area were cultured to investigate the type of mycobacteria involved in bovine tuberculosis. Employing the concentration method, 56 out of 530 cattle were found to be culture positive for acid-fast bacteria, 48 being Mycobacterium bovis and eight atypical mycobacteria. No M tuberculosis or M avium was isolated. Most of the isolated M bovis strains were found to be highly virulent for rabbits.