Estimation of uranium concentration in Indian monazite samples by using HPGe semiconductor detector.

Various techniques are available for the estimation of uranium concentration in geological rock samples. In the uranium exploration program in India, the beta-gamma technique is widely used by the Atomic Minerals Directorate for Exploration and Research (Department of Atomic Energy) to estimate uranium concentration in natural rock or soil samples. Uranium concentration cannot be estimated accurately by the beta-gamma technique if the sample has high concentrations of thorium. Because the ratio of thorium to uranium concentration varies between 15 and 30 in monazite samples, uranium concentration in monazite samples cannot be estimated accurately by the conventional beta-gamma technique. Uranium concentration in monazite samples can be estimated by measuring the 1.001 MeV gamma ray peak of Pa-234 (which is a decay product of uranium having a half-life of 1.17 min) using a P-type HPGe semiconductor detector. In this paper, uranium concentrations in 10 samples of Indian monazites were estimated using the P-type HPGe semiconductor detector, in which the average thorium concentration was 9.5%.

Clinical outcome and molecular characterization of pediatric glioblastoma treated with postoperative radiotherapy with concurrent and adjuvant temozolomide: a single institutional study of 66 children.

BACKGROUND: Glioblastoma (GBM) in children is rare. Pediatric GBM have a distinct molecular profile as compared to adult GBM. There are relatively few studies of pediatric GBMs and no standard of care on adjuvant therapy. We aimed to evaluate the clinical outcome and molecular profile of pediatric GBM. METHODS AND MATERIALS: Between 2004 and 2013, 66 consecutive children with histologically proven GBM were identified from our database. The majority of the children underwent maximal safe resection followed by focal radiotherapy with concurrent and adjuvant temozolomide. Immunohistochemical staining was performed for p53, MIB-1 labeling index, MGMT overexpression, and EGFR amplification and isocitrate dehydrogenase (IDH1) R132H point mutation. Survival and impact of possible prognostic factors on outcomes were analyzed. RESULT: Median survival was 15 months. The overall survival rate at 1 year was 62%, at 2 years was 30%, and at 3 years was 27%. Patients with thalamic tumors (P < .001), incompletely resected tumors (P < .00001), and tumors with MIB-1 labeling index >25% (P < .002) had poor overall survival rates. p53 was overexpressed in 74% of patients, MGMT promoter methylation was seen in 37% of patients, IDH1 mutation was seen in 4% of patients, and no patients had EGFR amplification. MGMT methylation and p53 overexpression did not impact survival. CONCLUSIONS: Clinical outcome of pediatric GBM is similar to that reported for adult GBM. The frequency of p53 overexpression is higher than in adult GBM, while MGMT methylation, IDH1 mutations and EGFR amplification is lower than in adult GBM. MGMT methylation and p53 expression status do not have any prognostic significance.

Extradural approach for cavernous hemangioma of the cavernous sinus: experience with 13 cases.

The clinical, radiological, and surgical issues concerning cavernous hemangiomas located within the dural confines of the cavernous sinus were analyzed on the basis of experience with 13 cases. The feasibility of radical resection by an entirely extradural approach using a basal temporal surgical route to this relatively rare and formidable surgical problem was investigated. Thirteen patients, four males and nine females, with cavernous hemangioma involving the cavernous sinus were treated from 1992 to 2001. The patients were aged from 15 to 55 years. Headaches and deficits of the cranial nerves coursing through the cavernous sinus were the principal symptoms at presentation. Vision was affected in four patients. The radiological features in all patients were similar with a characteristic pattern of extension and encasement of internal carotid artery. The maximum size of the tumor was 28 to 73 mm (mean 44 mm). An entirely extradural route using the basal temporal approach was used successfully in seven cases. Total resection was achieved in 12 patients and partial resection was achieved in one patient. The follow up ranged from 8 months to 9 years (mean 45 months). The outcome of extraocular movements was poor in our series, possibly due to the massive sizes of the tumors encountered. There was no recurrence or growth of the residual tumor and all patients were leading active lives.

Primary hemangioma of the occipital bone in the region of the torcula--two case reports.

Two rare cases of subtorcular occipital bone hemangioma occurred in 26-year-old and 30-year-old female patients. Partial resection was performed in both cases because of the proximity to the torcula. No recurrence was seen at follow-up examination at 9 and 12 months.

Synthesis of cytarabine lipid drug conjugate for treatment of meningeal leukemia: development, characterization and in vitro cell line studies.

Cytarabine (Cyt) used in the treatment of meningeal leukemia is associated with drawbacks like non selectivity to tumor cells, very short half-life and inability to cross blood brain barrier (BBB) due to its hydrophilic nature. Therefore, stable lipid drug conjugate (LDC) of Cyt with stearic acid was prepared. LDC was characterized by NMR, FTIR, DSC and XRD studies. Polysorbate 80 stabilized nanoparticles of this LDC (LDC-NP) were prepared using solvent injection method and characterized for size, zeta potential and loading efficiency. The LDC-NPs were loaded with appreciable amount (considering hydrophilic nature of drug, prior to conjugation) of drug conjugate (58.39 +/- 4.69%). The prepared LDC-NPs had smooth surface, particle size of 136.80 +/- 3.24 nm, were non-aggregated and had almost spherical and uniform shapes. In vitro release pattern showed initial fast release (14.89 +/- 0.056% in 1 h) followed by sustained release up to 72 h (76.26 +/- 0.156%). The blank stearic acid nanoparticles showed no significant cytotoxic effect on leukemic EL-4 cells and LDC-NPs were more cytotoxic than Cyt solution at 48 h. The lyophilized LDC-NPs were found to be physically stable with respect to size and zeta potential at refrigerated condition for 90 days. These results suggest that Polysorbate 80 stabilized LDC-NPs can be explored for treatment of meningeal leukemia owing to their ability of providing sustained drug release, stability and improved cytotoxicity in leukemic EL-4 cell line.