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ABSTRACTThe rheological properties of bitumen largely influence the performance of the pavement. Determination of rheological properties of bitumen depends on thermal equilibrium time. The main objective of this study is to evaluate the effect of Evotherm, a chemical warm mix additive on the thermal equilibrium time of bituminous binders. The bituminous binders used for this study included two unmodified binders, a polymer-modified bitumen (PMB) and a crumb rubber-modified bitumen (CRMB). The thermal equilibrium times for bituminous binders with and without Evotherm were measured using a dynamic shear rheometer. The results indicate that the thermal equilibrium time primarily depends on the type of binder, wherein the asphaltene content, presence of polymer and rubber influence thermal equilibrium time. The higher thermal equilibrium times observed for the Evotherm-modified PMB40 binder and Evotherm-modified CRMB60 binder in unaged condition can be attributed to a change in morphology and chemical interaction respectively upon the addition of Evotherm. Lesser thermal equilibrium time exhibited by short-term aged Evotherm binders can be because of the reduced formation of ageing compounds due to reduced short-term ageing temperature and presence of Evotherm. The linear regression model well predicted the thermal equilibrium time based on test temperature and softening point of binders.

The number of adults seeking orthodontic treatment has consideringly increased in the last 25 years. The adults fall into two categories, young adults and older adults. Treatment in adults is in all ways different from children and adolescents. The aim of this study was to assess the orthodontic treatment needs in adult patients. This was a retrospective study which was performed in a university setting. Data of patients who had routine dental check private teaching hospital Chennai, from June 2019 to March 2020, were collected. Records of 41,190 patients were analyzed. Inclusion criteria for the study were patients above the age of 30 years. Exclusion criteria were patients with incomplete record or repetitive data. There were three people involved in this study: the guide, reviewer, and researcher. All the available data was collected and sorted. The patient detailed case sheets were analyzed using the parameters such as age, gender, and treatment advised. Cross verification of the data was done by the second reviewer in order to avoid any missing or repetitive data using photographs, and tabulated in Excel. The final sample obtained for the study included records of 21,976 patients. Once the results have been tabulated based on the parameters, the data was then exported to SPSS software for statistical analysis. Descriptive statistics and chi square tests were done between the parameters: gender, age, and treatment options.

Allelic losses of 1p and 19q arms correlate with the oligodendroglial phenotype as well as with sensitivity to radiotherapy and chemotherapy. Furthermore, the DNA repair gene, methylguanine methyltransferase (MGMT), is diminished in 80% of oligodendroglial tumors and represents a possible mechanism for this therapeutic sensitivity. However, the authors questioned the relevance of genetic testing and measuring MGMT levels in tumors that were diagnostic of oligodendroglioma.The authors performed a retrospective analysis of 1p, 19q, 9p21, TP53, and MGMT status in 46 patients with oligodendrogliomas to address any relations that may exist among these markers with regard to progression‐free survival (PFS) and total survival. Methodologies included comparative genomic hybridization; loss of heterozygosity (LOH) on 1p, 19q, and 9p21; TP53 mutational analysis; and immunohistochemistry for MGMT.The authors found that survival among patients with light microscopically diagnosed oligodendroglial tumors demonstrating LOH of 1p and 19q trended toward statistical significance (P = 0.102 and P = 0.058, respectively). 9p21 LOH was significant as a predictor of PFS only among anaplastic oligodendrogliomas in this cohort (P = 0.033). TP53 mutation was found to be significantly predictive of a shorter survival (P = 0.027) among all patients and exhibited a strong trend toward a shorter PFS (P = 0.060). Low‐level MGMT labeling index (LI) (< 20%) was noted in 86% of all oligodendroglial tumors. MGMT LI was not found to correlate with an improved PFS or total survival in this cohort, recognizing that median survival was not reached after a median follow‐up of 104 months.9p21 and TP53 mutational status assisted in developing a stricter subclassification of these tumors with prognostic significance. MGMT levels were decreased in a majority of oligodendrogliomas. Cancer 2005. © 2005 American Cancer Society.

Penicillin-resistant Streptococcus pneumoniae (PRSP) is widespread all over the world, including countries previously free of PRSP. This study was undertaken to determine the prevalence, the common serotypes and the clonality of PRSP isolated over a period of 1 year, from various clinical samples from three major hospitals in Kuwait. Strains were identified by standard methods and their antibiotic susceptibility was determined by the agar dilution method. The clonality of the isolates was determined by repetitive extragenic palindromic sequence–polymerase chain reaction (REP–PCR) genomic profiling and pulsed field gel electrophoresis (PFGE). Serotyping was done by Quellung reaction using specific antisera. We found that 55% of the S. pneumoniae were resistant to penicillin (46% and 9% exhibited intermediate and full resistance, respectively). Nearly 41% were resistant to sulfamethoxazole-trimethoprim, 9% to cefotaxime and ceftriaxone, 15% to amoxycillin-clavulanate, 17% to cefuroxime, 77% to cefaclor, and 14% to clindamycin. The commonest serotypes among the PRSPs were 6A, 6B, 14, 19F, 23F and nontypable. PFGE and REP–PCR patterns showed a large diversity of genetic clones of the PRSP. Serotypes 6B, 14, 19F and 23F were more clonally related than the others. Our data showed that the prevalence of PRSP was high, the serotypes were diversified and different genetic clones make up the population of circulating PRSP in Kuwait.

The gene for von Recklinghausen neurofibromatosis [(NF)-1] has been cloned and evidence is accumulating that the NF-1 protein plays a role in the regulation of Ras protein function. Germ line mutations in the p53 gene were detected in family members of patients with the Li-Fraumeni syndrome, suggesting that the presence of a mutant p53 allele may be responsible for the increased risk of cancer in these families. The facioscapulohumeral muscular dystrophy locus has been assigned to 4q35-qter. In the fragile X syndrome, a breakpoint cluster region that exhibits DNA fragment length variation and hypermethylation was detected within the coding region of a candidate gene, designated fragile X mental retardation (FMR)-1]

Childhood ependymomas exhibit epidemiologic, anatomic, histologic, and biologic features that distinguish them from other gliomas. Because of their propensity to grow in functionally sensitive regions of the brain, adequate tumor sampling for basic and therapeutic research is limited. We have established xenografts in both subcutaneous and intracranial nude mouse systems (D528 EP-X, D612 EP-X) from the ependymomas of two nonrelated children. Median subcutaneous growth rates (reported in days to grow from 200 mm3 to 1000 mm3) are 82 days for D528 EP-X (n=10) and 50 days for D612 EP-X (n=10). D528 EP-X grows intracranially with a median postimplantation survival of 85 days (n=10); D612 EP produces a median postimplantation survival of 72.5 days (n=10). Both xenografts grow as well-formed masses with no evidence of infiltration into either brain or subcutaneous tissues. While perivascular pseudopalisading is found in both xenografts, true ependymal rosette formation is absent. Ultrastructurally, neither xenograft exhibits cilia, but both produce abundant intermediate filaments. By light microscopy, the neoplastic cells are immunoreactive for the intermediate filaments glial fibrillary acidic protein, vimentin, and nestin. Karyotypically D528 EP exhibits 46,XX,del(6)(q22q26)/46,XX while D612 EP exhibits 50,XX,÷X,t( 1 ;8)(p11 ;q 11 ),t( 1 ;8)(p 11 ;q 11),+1 ,−4,der(5)t(4;5)(q 12;q35),+der(5)t(4;5)(q 12;q35),−6,÷9, +9,−16,+der(17)t(6;17)(p11;p11),+mar. Restriction fragment length polymorphism studies comparing the primary brain tumor tissue from each patient against multiple passages of the resulting xenografts confirm the origin of both xenografts. These xenografts represent models on which future studies into the oncogenesis, progression and therapy of ependymomas can be performed.

OBJECTIVE: To study the clinical presentation, endoscopic features and prevalence of Helicobacter pylori in duodenal ulcer (DU) patients in southern Saudi Arabia, located 3150 m above sea level, and to compare results with those from low altitude regions of the Kingdom.METHODS: Prospective study of patients with proven DU referred for upper gastrointestinal endoscopy at Asir Central Hospital, Abha, southern Saudi Arabia over an 18-month period.RESULTS: Of 126 patients with proven DU, 72% were men and mean age was 40.4 years (range 18 to 68). Twenty-eight per cent were smokers and only 5% used nonsteroidal anti-inflammatory drugs. Thirty-eight patients (30%) presented with hematemesis or melena, and the majority had a single ulcer. Nineteen per cent of patients with dyspepsia had DU and 96% had H pylori. These results are comparable with those reported from the low altitude, warmer regions of Saudi Arabia.CONCLUSIONS: Age of patients and the male:female ratio were similar to those in developing countries. The frequency of smoking is lower than in western countries and no patient in this report consumed alcohol. High altitude did not affect the prevalence of DU or the frequency of H pylori because the results were comparable with those from the low altitude areas of the Kingdom of Saudi Arabia and other lowland developing countries. Although great socioeconomic changes have increased the incidence of heart disease, the patterns of DU and H pylori infection assume those in developing nations.