Biomedical subjects
R Caplan
Publications and source records attributed to R Caplan.
Impact of a multileaf collimator on treatment morbidity in localized carcinoma of the prostate.
PURPOSE: To evaluate the effectiveness of variable multileaf collimation, three-dimensional treatment planning, and computer-controlled conformal radiation therapy of prostate cancer. METHODS AND MATERIALS: Two hundred and forty-five patients with locally advanced prostate cancer have completed treatment over a 9-year time span using a multileaf collimator and conformal treatment techniques on the University of Washington cyclotron. All patients had three-dimensional treatment planning with computed tomography scans in the treatment position, and had treatment fields individually shaped to the target volume with a continuously variable multileaf collimator. Treatment was delivered under computer control with network transfer of the multileaf collimator settings from the treatment planning computer to the cyclotron control system. RESULTS: The multileaf collimator combined with three-dimensional treatment planning results in elegant dose distributions. These neuron dose distributions resulted in a reduced local/regional tumor failure rate with no increase in complications when compared to control treatment with photons in a randomized trial. Neutron treatment delivered at other institutions without conformal beam shaping resulted in the same improvement in local-regional tumor control rates, but was associated with a significantly higher normal tissue complication rate than seen with conformal neutron beam delivery techniques (grade 3 and 4 cumulative late normal tissue toxicity rates of 39% vs. 10%, p = 0.0007). CONCLUSIONS: Conformal treatment of prostate cancer using a multileaf collimated neutron beam results in increased local/regional tumor control rates with low normal tissue toxicities. This experience is directly applicable to the conformal treatment of prostate cancer with photons.
Community survey of long term daytime use of benzodiazepines.
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Blink rate in childhood schizophrenia spectrum disorder.
Spontaneous blink rate, a putative measure of dopamine function, was measured in schizophrenic, schizotypal, and normal children, aged 5.6-13.2 years during three different cognitive tasks. Unlike that of schizophrenic adults, the blink rate of the schizophrenic children who were not on neuroleptics was significantly lower than that of the normal children. There were no statistically significant differences, however, in the blink rates of the neuroleptic-treated schizophrenic children and the normal children. The schizophrenic and schizotypal children had similar spontaneous blink rates. Within each diagnostic group, the blink rate was lowest for listening, intermediate for conversation, and highest for verbal recall. These findings highlight the need to examine the relationship between age, blink rate, and dopamine function in childhood-onset schizophrenia spectrum disorder.
Communication deficits in childhood schizophrenia spectrum disorders.
This article examines the effects of age, cognition, and discourse skills on the clinical manifestations of formal thought disorder in 31 children with schizophrenia, 14 with schizotypal personality disorder (SPD), and 70 who were normal. The communication deficits of the 31 children with schizophrenia have three characteristics: illogical thinking, loose associations, and impaired discourse skills. Loose associations and illogical thinking reflect different aspects of impaired attention/information processing in children with schizophrenia. Only certain aspects of the discourse deficits of the children with schizophrenia are associated with the cognitive measures used in this study. The children with SPD have similar illogical thinking and loose associations scores but a narrower range of discourse deficits than the children with schizophrenia. Implications of the interaction between the clinical, cognitive, and discourse manifestations of the communication deficits of children with schizophrenia are discussed. The possible relationship between these manifestations and positive and negative symptoms of schizophrenia are also reviewed.
Thought disorder in childhood.
OBJECTIVE: This paper delineates the evolution of the concept of thought disorder and presents a developmental/neurobehavioral theory of the main components of formal thought disorder in childhood-onset schizophrenia. METHOD: A review of past and recent clinical, cognitive, and linguistic studies of thought disorder in childhood-onset schizophrenia presents the main features and changes in the thought disorder concept. RESULTS: The review emphasizes that, in the past, this term was used to describe a variety of clinical manifestations in a heterogenous group of children because of the lack of distinction between childhood schizophrenia and infantile autism. The studies that have been conducted during the past 15 years, however, have demonstrated well-defined clinical components of thought disorder and their cognitive/information processing, linguistic/pragmatic, and biological correlates. CONCLUSIONS: A functional conceptualization of formal thought disorder in childhood-onset schizophrenia is presented in light of the theoretical and clinical implications of the reviewed studies.
Leprosy in Iowa: 1860-1954.
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Dr. Oliver Wendell Holmes.
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Prognostic factors in stage D2 prostate cancer treated with a pure nonsteroidal antiandrogen.
BACKGROUND: Prognostic factors have been shown to be important when stratifying patients with prostate cancer into randomized trials and counseling the individual patient regarding his chances of response to treatment. However, there are no reports on prognostic factors in patients with Stage D2 prostate cancer treated with a pure antiandrogen as monotherapy. METHODS: The authors studied a variety of possible prognostic factors among 150 patients with metastatic prostate cancer treated with an antiandrogen (Casodex, Imperial Chemical Industries, Wilmington, DE). RESULTS: In a univariate analysis, performance status; extent of disease (EOD); pretreatment hemoglobin, alkaline phosphatase, prostate-specific antigen (PSA), and prostatic acid phosphatase (PAP) levels; and extent of disease (EOD) on bone scan all were found to be significant prognostic factors (P < 0.05). Pretreatment serum testosterone levels, identified as one of the most important prognostic factors, was not identified as significant in the current study. CONCLUSIONS: Although the pretreatment testosterone level was shown to be an important prognostic factor in previous studies, using other modes of androgen ablation (reducing testosterone to below castrate levels), the current study suggest it may not be a helpful factor if the therapy used is antiandrogens as monotherapy. This may relate to the different mode of action of antiandrogens, which do not reduce serum testosterone levels.
Communication deficits in children undergoing temporal lobectomy.
OBJECTIVE: To examine formal thought disorder and discourse (cohesive) devices that make speech coherent prospectively in seven children, aged 5.7 to 16.7 years, before and after temporal lobectomy for intractable cut points determined from sensitivity and specificity analyses of formal thought disorder and discourse measures in 22 children with complex partial seizure disorder and 45 normal children. RESULTS: Before surgery, the mean illogical thinking and discourse scores of the surgical candidates were in the pathological range. After a mean postoperative follow-up period of 15.1 months, their illogical thinking (but not their discourse scores) decreased significantly to the normal range. CONCLUSIONS: These preliminary findings are discussed in terms of the possible role of postsurgical changes in seizure control, behavior, antiepileptic drugs, cognition, and prefrontal function.
Hemispherectomy for intractable seizures: presurgical cerebral glucose metabolism and post-surgical non-verbal communication.
This study examined the presurgical 2-deoxy-2[18F]-fluoro-D-glucose positron emission tomography (PET) patterns of regional cerebral glucose metabolism in the non-resected hemisphere of 13 children who underwent hemispherectomy for early-onset intractable seizures. These patterns were compared with the rate of change in the children's non-verbal communication scores, measured before and after surgery. Irrespective of the side of surgery, the pre-operative glucose metabolism in the non-resected prefrontal cortex correlated significantly with the postoperative rate of change in the children's ability to focus the attention of an adult on an object or event (joint attention). These preliminary findings suggest that pre-operative PET patterns might be associated with certain aspects of the developmental outcome of children undergoing hemispherectomy.
Communication deficits and formal thought disorder in schizophrenic children.
This study examined 31 schizophrenic children to determine if they used discourse devices that make speech coherence differently from sex and mental age matched normal children. It also investigated whether the discourse deficits of the schizophrenic children were related to clinical measures of formal thought disorder. Using Halliday and Hassan's analysis of cohesion, the authors found that schizophrenic children underutilize some discourse devices and overutilize others. Several of their discourse deficits were similar to those described in schizophrenic adults. The schizophrenic children, however, also had additional discourse deficits, which probably reflect developmental delays. The authors also demonstrated that the schizophrenic children with loose associations had different discourse deficits and discourse/IQ correlates than schizophrenic children without loose associations. The schizophrenic children receiving neuroleptic medication had lower loose associations scores than the unmedicated subjects. The authors discuss the possible confounding effect of medication and loose associations, as well as the developmental, cognitive, and clinical implications of the study's findings.
Communication deficits in childhood schizotypal personality disorder.
This study examined the similarities and differences in the communication deficits of 13 schizotypal and 12 schizophrenic children matched by age and IQ. Like schizophrenic children, schizotypal children underutilize some discourse devices necessary for coherent speech and overutilize others. Schizotypal children, however, appear to display a more restricted range of discourse deficits than schizophrenic children. In addition, their discourse deficits do not appear to be associated with clinical measures of loose associations. The clinical implications and the potential use of discourse measures to differentiate schizophrenic and schizotypal children are discussed.
Formal thought disorder in pediatric complex partial seizure disorder.
We compared the formal thought disorder ratings of 27 children with complex partial seizure disorder, 31 schizophrenic children and 58 normal children. The epileptic children with fullscale IQ scores below 100 had significantly more formal thought disorder than normal children with a similar IQ. The severity of their formal thought disorder was related to the age of seizure onset, seizure control and a diagnosis of schizophrenia spectrum disorder. The schizophrenic children had thought disorder irrespective of IQ scores. The cognitive correlates of their formal thought disorder scores differed from those of the epileptic children. Possible anatomical substrates of thought disorder in childhood complex partial seizure disorder and schizophrenia are discussed.