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A Wojtowicz

Publications and source records attributed to A Wojtowicz.

26 records · Page 2Linked to original sources
PubMedDate not supplied

School-based methylphenidate placebo protocols: methodological and practical issues.

Around 1990, psychologists and educators began to notice increasing use of methylphenidate by students. Diagnosis of attention-deficit/hyperactivity disorder by family physicians and pediatricians was most commonly based on brief behavioral descriptions by parents and, infrequently, by use of rating scales. At that time, the present researchers began to explore the development of a school-based, methodologically sound, and inexpensive method of assessing the efficacy of stimulant medications, which would ensure reasonable compliance by teachers, parents, and students in monitoring the effects of medications and placebos. This article focuses on the methodological issues involved in choosing instruments to monitor behavior, once a comprehensive evaluation has suggested trials on Ritalin. Case examples illustrate problems of teacher compliance in filling out measures, supplying adequate placebos, and obtaining physician cooperation, and with the practical issue of providing adequate data without overwhelming the time and resources of participants. Emerging school-based methodologies are discussed with recommendations for future efforts.

Attention Deficit Disorder with Hyperactivity↗
PubMedDate not supplied

Dating of palaeoanthropological nuragic skeletal tissues using electron paramagnetic resonance (EPR) spectrometry.

Dating of skeletons of Nuragic population living in Sardinia island centuries BP, based on the quantitative evaluation of the concentration of stable paramagnetic species produced by ionising radiation in tooth enamel was performed by using EPR spectrometry. Applying the additive dose method (60Co gamma rays) and comparative calculations based on analogous measurements done with Roman skeleton of the known age as discovered close to Nuragic tomb (Tombs of Giants, La Testa S. Teresa di Gallura, Sardinia) the age of Nuragic skeleton was evaluated as equal to about 3,200 years (1,200 years BC). The total error of EPR measurements and dose extrapolation was estimated for 10-12%. Crystallinity of bone mineral in Nuragic skeleton evaluated by the EPR technique, adapted earlier by some of the authors of the present paper for biomedical studies on mineralised tissues, is only little changed after the centuries of its deposition in the tomb when compared with contemporary bone tissue. Comparison of chemical composition of Nuragic skeleton contaminated through slow percolation by rain of floods with that of contemporary bone sample shows the increase of the concentration of Fe, PO4, SiO2, Al and Mg, Fe, SiO2, AP are not present in contemporary bones. As expected, the contamination was minimal in tooth enamel.

Bone Density↗
PubMedDate not supplied

Early and transient osteopetrosis in microphthalmic MIB-rats.

Microphtalmic blanc mutation (mib/mib) displays a very mild form of osteopetrosis in rats. The autosomal recessive mib mutation shows pleiotropic expressions in homozygotes. Microphtalmia, absence of eye and skin pigmentation, retardation in the tooth eruption were observed in the mutants. Most bone abnormalities occurred in newborns. An increased radiological opacity of long bones, persistence of primitive bone in medullary cavities, reduced number of poorly differentiated osteoclasts in mandibulae, reduced number of mononuclear peritoneal cells as well as reduced number of mononuclear osteoclast precursors in peritoneal cell population were found. In 3 weeks old and in adult mutants, both bone structure and the number of mandible osteoclasts appear normal, but the number of blood monocytes, peritoneal cells and mononuclear osteoclast precursors in peritoneal cell population remain significantly lower than in the healthy littermates. These observations indicate that the early failure of osteoclast differentiation and maturation is transient in the mib/mib form of osteopetrosis.

Abnormalities, Multiple↗