Clinical and prognostic aspects of adrenocortical neoplasms in childhood

BACKGROUND: A retrospective study of 54 children was undertaken to define the clinical presentation and secretory patterns of adrenal tumors and to evaluate the outcome of surgical resection and medical therapy. PROCEDURES: Different factors were studied in univariate and multivariate analysis by using the Cox proportional hazard model. RESULTS: Median age at diagnosis was 4 years. Boys and girls were affected equally. The disease was revealed by virilization (61%) or by a palpable mass (39%) with a 0.1-5.5 year delay from initial symptoms. At initial examination, we found that 76% of children were virilized. Ninety-four percent of the tested tumors secreted androgens, which were associated with glucocorticoids in 36%. Adrenal tumors in children were smaller than in adults. Half of them measured less than 10 cm. There were recurrences in 40% of children. The survival rate at 5 years was 49%, 70% if resection was microscopically complete and 7% if not (P < 0.001). CONCLUSIONS: In children, rare adrenal tumors have different diagnostic and prognostic characteristics than in adults; however, recurrences remain frequent. The efficacy of chemotherapy, mainly o,p'-DDD (Mitotane), remains to be evaluated in comparative trials.     

Evaluation of Ethylcellulose as a Matrix for Prolonged Release Formulations. II. Sparingly Water-Soluble Drugs: Ibuprofen and Indomethacin

The main purpose of this investigation was to evaluate ethylcellulose as a carrier for the preparation of prolonged release solid dispersions of sparingly water-soluble drugs, ibuprofen and indomethacin. Solid dispersions containing various concentrations of ethylcellulose of different viscosity grades were prepared by the solvent method. Tablets were directly compressed from solid dispersions (40/100 mesh) with 0.5% Primojel as a disintegrant and 0.5% magnesium stearate as a lubricant. In vitro release studies employed a rotating bottle system with Sorenson's buffer solution (pH 7.4). It was found that prolongation of drug release was primarily associated with an increase in amount of ethylcellulose rather than the viscosity grade. Nonetheless, the higher the viscosity grade of ethylcellulose, the slower the release of drug from granular and compressed solid dispersions. The release rate of ibuprofen was faster than that of indomethacin from different solid dispersion formulations.     

Model multiple antigenic and homopolymeric peptides from non-repetitive sequences of malaria merozoite proteins elicit biologically irrelevant antibodies

We describe here a new type of mitochondrial mutation (dum24; for dark uniparental minus inheritance) of the unicellular photosynthetic alga Chlamydomonas reinhardtii. The mutant fails to grow under heterotrophic conditions and displays reduced growth under both photoautotrophic and mixotrophic conditions. In reciprocal crosses between mutant and wild-type cells, the meiotic progeny only inherit the phenotype of the mating-type minus parent, indicating that the dum24 mutation exclusively affects the mitochondrial genome. Digestion with various restriction enzymes followed by DNA gel blot hybridizations with specific probes demonstrated that dum24 cells contain four types of altered mitochondrial genomes: deleted monomers lacking cob, nd4, and the 3' end of the nd5 gene; deleted monomers deprived of cob, nd4, nd5, and the 5' end of the cox1 coding sequence; and two types of dimers produced by end-to-end fusions between monomers similarly or differently deleted. Due to these mitochondrial DNA alterations, complex I activity, the cytochrome pathway of respiration, and presumably, the three phosphorylation sites associated with these enzyme activities are lacking in the mutant. The low respiratory rate of the dum24 cells results from the activities of rotenone-resistant NADH dehydrogenase, complex II, and alternative oxidase, with none of these enzymes being coupled to ATP production. To our knowledge, this type of mitochondrial mutation has never been described for photosynthetic organisms or more generally for obligate aerobes.     

Comparison of digital rectal examination and biopsy results with the radical prostatectomy specimen

PURPOSE: Digital rectal examination is integral to staging prostate cancer. Ultrasound guided biopsy establishes the diagnosis, and it may provide useful information regarding disease grade and extent. Treatment decisions are largely based on information gained from digital rectal examination and biopsy but this information is only useful if it correlates with the radical prostatectomy specimen and prognosis. We correlated digital rectal examination and transrectal ultrasound guided biopsy results with a detailed analysis of the radical prostatectomy specimen. MATERIALS AND METHODS: The accuracy of an abnormal digital rectal examination for predicting the location and extent of cancer was assessed in 89 patients thought to have clinical stage T2 disease. We evaluated 155 patients with clinical stages T1c and T2 disease to correlate the location of positive biopsies with the tumor site in the prostate. Radical prostatectomy specimens were completely sectioned at 2 mm. intervals, and tumor extent and location were recorded. RESULTS: In 85 patients a unilateral lesion was suspicious on digital rectal examination, that is stage cT2. The final pathological review revealed cancer on the suspicious side in 82 cases (96%) with tumor confined to the same lobe in only 23 (27%), bilateral disease in 59 (69%) and tumor confined to the contralateral lobe in 3 (4%). In 4 patients with a palpable bilateral abnormality a bilateral lesion was confirmed on final pathological evaluation. Digital rectal examination demonstrated a 36 and 31% incidence of extracapsular tumor extension and positive surgical margins, respectively, on the clinically benign side. In 100 patients only unilateral biopsy was positive. The final pathological evaluation revealed cancer in the biopsy positive side in 95 cases (95%) with tumor confined to the ipsilateral lobe in only 26 (26%), bilateral disease in 69 (69%) and tumor confined to the contralateral lobe in 5 (5%). In 46 of the 55 patients (84%) with bilateral positive biopsies tumor involved both sides but the pathologist did not identify cancer in both lobes in 9 (16%). While 100 patients had a unilateral negative biopsy, analysis of the prostatectomy specimen revealed carcinoma in the benign lobe in 74 (74%). Moreover, extracapsular tumor extension and a positive surgical margin were observed on the biopsy negative side in 31% of the patients. The degree to which digital rectal examination and biopsy results confirmed the final pathological evaluation was assessed using the kappa statistic, which revealed only slight agreement with each factor. The correlation of digital rectal examination and biopsy results with the location of extracapsular extension and positive margins was evaluated by the Spearman coefficient of correlation, which indicated poor agreement. When patients with unilateral versus bilateral positive biopsy were compared with respect to prognostic parameters, the difference was statistically significant for initial serum prostate specific antigen, the percentage of surface involved by tumor, biopsy and final Gleason scores, and the incidence of extracapsular extension of tumor. CONCLUSIONS: Digital rectal examination and the interpretation of prostate biopsy are not accurate clinical tools for defining the location and extent of prostatic carcinoma. Bilateral positive biopsy may be useful as an adjunct to the current clinical staging system.     

The changing presentation of pyloric stenosis

A triplet pregnancy in a 23-year-old woman was terminated at 15 weeks of gestation because of her severe hypertension, lung edema, and secondary hyperthyroidism. The pregnancy consisted of a hydatidiform mole with a 46,XY karyotype and two fetuses each with 46,XX and a 46,XY karyotype. To determine the zygosity and genetic origin of the mole and fetuses, PCR- and computer-assisted genotyping were performed at 27 CA-repeat marker loci that were distributed evenly over the genome. As a result, genotypes of the three pregnancy products were distinct from each other, indicating that the triplets were trizygotic. The mole lacked any maternal alleles but inherited both of the paternal alleles and/or one paternal allele in duplicate. This, along with the XY sex chromosome constitution, indicated that the mole resulted from dispermic androgenesis. The mother developed a persistent trophoblastic tumor thereafter.     

Application of dried blood spot specimens for serologic subtyping of human immunodeficiency virus type 1 in Thailand

Dried blood spot (DBS) specimens were assessed as an alternative to plasma for human immunodeficiency virus type 1 (HIV-1) serotyping by V3 loop peptide enzyme immunoassay. Nested PCR capable of distinguishing HIV-1 subtypes B and E was used as the reference standard. Ninety-two percent of DBS samples were typeable as either HIV-1 subtype B or E. Serotype results with DBS and plasma were identical for 254 of 257 specimens. A simple DBS collection method provides a convenient alternative for conducting HIV-1 serotype surveillance while retaining sensitivity and specificity.     

The effect of surface energy on the heat transfer enhancement of paraffin wax/carbon foam composites

The influence of carbon foam surface energy on heat transfer through paraffin wax/carbon foam composite was investigated. Carbon foam samples were surface treated and their corresponding surface energy values were measured. A theoretical model was formulated to analyze the mass of paraffin wax absorbed for both pristine and surface activated carbon foam samples based on the concept foam wettability. An experimental study was carried out for heating of the wax/carbon foam composite samples to study the phase change heat transfer due to the melting of wax within the foam matrices. The above studies showed that a greater mass of wax was absorbed within the activated carbon foam samples as compared to the pristine sample which can be due to their greater wettability. This resulted in an improvement in heat transfer rate for the activated samples. The total energy storage rate for the activated composite samples was compared with the pristine sample for the same heating duration and an enhancement of more than 18% was observed for the two activated samples. These studies revealed that the surface energy of carbon foams can play an important role in improving the overall thermal performance of wax/carbon foam composites.