Bone Density in Survivors of Childhood Cancer

Advances in combination chemotherapy, radiation therapy, surgery, and bone marrow transplantation have resulted in markedly improved survival rates for many children with cancer. Advancements in therapy, however, have led to new concerns, namely long-term consequences of effective treatments. Young adult and adult survivors of childhood cancer are at risk for a number of disorders related to therapy. Specifically, the young adult who has survived cancer, attendant treatments, and their complications is at risk for factors that can lead to suboptimal acquisition of peak bone mass. These factors include chronic illness, nutritional deficiencies, limited physical activity, and treatment with glucocorticoids, multiagent chemotherapy, and radiation. The long-term adverse effects of these therapies on endocrine systems, especially sex steroid and growth hormone deficiencies, are additional risk factors for some patients. After a brief review of the processes associated with acquisition of peak bone mass in the young adult, this article examines the impact of cancer and cancer therapy on bone mineral density in survivors of childhood cancer.     

Failure to demonstrate complement activation during bronchial challenge test

In order to demonstrate a possible complement activation during early bronchospastic reaction in asthma, we have measured plasmatic C3d (a split product of C3) and the C3d/C3 index, both of which are sensitive indices of complement activation. Twenty-nine allergenic bronchial challenge tests were accomplished, with an absence of response in six cases, an early reaction in sixteen cases and a dual reaction in seven cases. Changes in plasmatic C3d or C3d/C3 five min after an early reaction, or five min after the last dose of allergen (in the six cases without bronchial response) were insignificant. However, complement activation in the lungs during asthmatic reaction cannot be completely excluded without studies using the bronchoalveolar technique.     

Glutamic acid decarboxylase-like immunoreactivity in brainstem auditory nuclei of the rat

The distribution of GABA-producing neurons in the brainstem auditory nuclei of the rat was investigated immunohistochemically by using an antibody to glutamic acid decarboxylase (GAD). In the cochlear nuclei, GAD immunoreactive neurons are present only in the superficial granular and molecular layers, whereas terminals are found in all subdivisions of the nuclei and are particularly dense surrounding large spherical cells and one type of stellate cell. In the superior olivary complex, GAD immunoreactive neurons are located in the lateral olivary nucleus and throughout the periolivary region. Immunoreactive terminals are distributed along dendrites of principal cells of the medial and lateral olivary nuclei and are clustered around somata of globular neurons of the nucleus of the trapezoid body. An extremely dense band of immunoreactive somata and terminals is present along the ventral edge of the olivary complex. The ventral, intermediate, and dorsal nuclei of the lateral lemniscus contain small fusiform GAD-immunoreactive neurons and a moderately dense plexus of immunoreactive terminals. The inferior colliculus contains a large population of GAD-immunoreactive perikarya and an extremely dense accumulation of immunoreactive terminals in the central, dorsomedial, and external nuclei. These observations indicate that GABA systems are involved in function at all levels of the brainstem auditory pathway.     

Lack of correlation between ex vivo apical dye penetration and presence of apical radiolucencies.

OBJECTIVE: The aim of this study was to determine if there is a significant correlation between the in vivo presence of periapical radiolucency and ex vivo apical dye penetration on the same human teeth. STUDY DESIGN: Eighty-four endodontically filled teeth that were scheduled for extraction were classified into 2 groups according to the presence or absence of a periapical radiolucency and further divided into 2 subgroups according to the quality of the root canal filling. After extraction, the apical filling was evaluated by a dye penetration method. RESULTS: The dye extraction evaluation showed no correlation between apical dye penetration and the presence of a periapical radiolucency (not significant), but a statistically significant correlation with the quality of the root canal filling (P = .03). CONCLUSION: The results of the dye penetration study were correlated to the quality of the root canal filling but had no predictive value for the development of periapical radiolucency.     

Relationship of resting energy expenditure with liver function and nutritional status in patients with alcoholic cirrhosis.

Resting energy expenditures (REEs) were measured in 40 alcoholic cirrhotic (AC) patients by indirect calorimetry and corrected for 24-h urinary creatinine and excretion. These REEs were compared according to the stage of severity of the cirrhosis, the nutritional status, and the presence or absence of alcoholic hepatitis (AH). Mean REE was not significantly different between the Child class A, B, and C patients, even when corrected for 24-h urinary creatinine. Mean REE was significantly less in malnourished AC than in well-nourished patients (1308 +/- 285 vs. 1531 +/- 255 kcal, p less than 0.02). However, when measured energy expenditure was corrected for 24-h urinary creatinine, the difference between the two groups of patients disappeared (1800 +/- 540 kcal/g creatinine in malnourished patients vs. 1890 +/- 780 kcal/g creatinine in well-nourished patients). Finally, there was no significant difference between the REE, corrected or not, for the 24-h urinary creatinine in AC with or without AH. Thus, when REE is normalized to lean body mass, represented by 24-h urinary creatinine, the metabolic activity in AC is not dependent on the severity of the cirrhosis, nutritional status, or existence of AH.     

In vitro development and stability of tolerance to cloxacillin and vancomycin inStaphylococcus aureus

The stability of tolerance ofStaphylococcus aureus during subculturing at 37°C and development of this property after repeated exposure to cloxacillin or vancomycin were investigated in vitro. Four of five tolerant strains lost this property during repeated subculturing at 37°C for 50 days. Conversely, tolerance emerged in two of four nontolerant strains after repeated cycles of exposure to 25 µg of cloxacillin/ml or 10 µg of vancomycin/ml alternating with growth in antibiotic-free medium. Previous in vivo exposure to cloxacillin did not enhance the development of tolerance in vitro. MICs of both cloxacillin and vancomycin did not change significantly during this procedure. Whether the conversion of nontolerant strains to the tolerant state can also occur during antibiotic exposure in treatment of patients remains to be determined.