Primary mesothelioma. A practical tutorial review.

TARGET AUDIENCE: Gastroenterologists, internists, and surgeons LEARNING OBJECTIVES: After completion of this article, the reader will be able to understand the main diagnostic features of this disease and the differential diagnosis with other entities that have a more benign outcome. The lack of acceptable treatment is explained.

Primary mesothelioma. A practical tutorial review

TARGET AUDIENCE: Gastroenterologists, internists, and surgeons LEARNING OBJECTIVES: After completion of this article, the reader will be able to understand the main diagnostic features of this disease and the differential diagnosis with other entities that have a more benign outcome. The lack of acceptable treatment is explained.

Primary mesothelioma. A practical tutorial review.

TARGET AUDIENCE: Gastroenterologists, internists, and surgeons LEARNING OBJECTIVES: After completion of this article, the reader will be able to understand the main diagnostic features of this disease and the differential diagnosis with other entities that have a more benign outcome. The lack of acceptable treatment is explained.

Autism: xenobiotic influences.

The advances in medical technology during the last four decades has provided evidence for an underlying neurological basis for autism. The etiology for the variations of neurofunctional anomalies found in the autistic spectrum behaviors appears inconclusive as of this date but growing evidence supports the proposal that chronic exposure to toxic agents, i.e., xenobiotic agents, to a developing central nervous system may be the best model for defining the physiological and behavioral data found in these populations. A total of 20 subjects (15 males and 5 females) who received a formal diagnosis of autism by a developmental pediatrician, pediatric neurologist, or licensed psychologist were included. The mean age for the sample was 6.35 yrs offnge = 3-12 years). This study employed several measures that collectively would provide evidence of burden levels of xenobiotic agents and abnormal liver detoxication processes. These included: (1) Glucaric Acid Analysis, (2) blood analyses for identification of specific xenobiotic agents, and (3) Comprehensive Liver Detoxification Evaluation. Kolmogorov-Smirnov testing for a chi-square and Normal distribution of the Glucaric Acid finding indicates that each of these distributions is significantly different from expected distributions (p < .01). It is most noteworthy that of the 20 cases examined for this study, 100% of the cases showed liver detoxication profiles outside of normal. An examination of 18 autistic children in blood analyses that were available showed that 16 of these children showed evidence of levels of toxic chemicals exceeding adult maximum tolerance. In the two cases where toxic chemical levels were not found, there was abnormal D-glucaric acid findings suggesting abnormal xenobiotic influences on liver detoxication processes. A proposed mechanism for the interaction of xenobiotic toxins with immune system dysfunction and continuous and/or progressive endogenous toxicity is presented as it relates to the development of behaviors found in the autistic spectrum.

Comprehensive predictions of outcome in closed head-injured patients. The development of prognostic equations.

A comprehensive diagnostic evaluation was administered to 162 closed head-injured patients within 1 to 21 days (mean, 7.5 days) after injury. Each evaluation consisted of (1) power spectral analyses of electroencephalogram (EEG) recorded from 19 scalp locations referenced to age-matched norms, (2) brainstem auditory evoked potentials, (3) computed tomography (CT)-scan, and (4) Glasgow Coma Score (GCS) at time of admission (GCS-A) and at time of EEG test (GCS-T). Functional outcome at one year following injury was assessed using the Rappaport Disability Rating Scale (DRS), which measures the level of disability in the six diagnostic categories of (1) eye opening, (2) best verbal response, (3) best motor response, (4) self-care ability for feeding, grooming, and toileting, (5) level of cognitive functioning, and (6) employability. The ability of the different diagnostic measures to predict outcome at one year following injury was assessed using stepwise discriminant analyses to identify patients in the extreme outcome categories of complete recovery versus death and multivariate regression analyses to predict patients with intermediate outcome scores. The best combination of predictor variables was EEG and GCS-T, which accounted for 74.6% of the variance in the multivariate regression analysis of intermediate outcome scores and 95.8% discriminant accuracy between good outcome and death. The best single predictors of outcome in both the discriminant analyses and the regression analyses were EEG coherence and phase. A gradient of prognostic strength of diagnostic measures was EEG phase greater than EEG coherence greater than GCS-T greater than CT-scan greater than EEG relative power. The value of EEG coherence and phase in the assessment of diffuse axonal injury was discussed.

Ingestion of carbohydrates varying in complexity produce differential brain responses.

Variations in the complexity of carbohydrate substances were studied with respect to their differential effects on brain function. Glucose, sucrose, fructose and corn starch were each administered as part of an oral carbohydrate tolerance test during 17 test trials. Brain EEG changes and blood glucose levels were monitored concurrently throughout a 5 hour period. The glucose solution produced more substantial EEG effects than the other three carbohydrate solutions. Absolute blood glucose level was the primary determinant of electrocortical changes found predominantly in the left parietal-occipital and left temporal cortical regions. Implications for the study and evaluation of cognitive function were discussed.

There is an inverse relationship between the presence of significant endoscopic findings and the amount of diazepam required to obtain adequate sedation in upper endoscopy.

A retrospective study was done in order to validate our observation that patients who require large doses of diazepam for sedation for upper endoscopy usually have less significant pathological findings than those who receive smaller, most of the patients (70%) who had significant endoscopic findings required 20 mg of diazepam or less. This was in contrast to patients requiring large doses of diazepam greater than 20 mg, who only had significant findings in 26.7% of the cases.

There is an inverse relationship between the presence of significant endoscopic findings and the amount of diazepam required to obtain adequate sedation in upper endoscopy.

A retrospective study was done in order to validate our observation that patients who require large doses of diazepam for sedation for upper endoscopy usually have less significant pathological findings than those who receive smaller, most of the patients (70

) who had significant endoscopic findings required 20 mg of diazepam or less. This was in contrast to patients requiring large doses of diazepam greater than 20 mg, who only had significant findings in 26.7

of the cases.

Premedication with meperidine and diazepam for upper gastrointestinal endoscopy precludes the need for topical anesthesia.

The authors conducted a prospective study in 90 patients undergoing upper endoscopic examination under sedation to determine whether there was any beneficial effect in anesthetizing the pharynx with topical anesthesia. These patients were divided into three groups of 30 patients. Group A received 39 ml of viscous lidocaine gargle (2%) diluted with 15 ml of tap water. Group B received the placebo. Group C received neither viscous lidocaine nor placebo. All patients received intravenous meperidine and diazepam titrated to produce adequate sedation for upper endoscopy. It was demonstrated that the undesirable effects of upper endoscopy, that is, gagging, sore throat, and dysphagia, did not differ significantly in any of the three study groups as evaluated by either the patients or the endoscopist. Only two patients complained that the procedure was mildly unpleasant. The authors conclude that the practice of anesthetizing the pharynx in patients receiving sedation for upper endoscopy should be abandoned since anesthesia of the pharynx is not exempt from morbidity and mortality as well as being time-consuming and expensive.

Computerized EEG analyses of autistic children.

Electroencephalographic measures of the neurophysiological dysfunction underlying autism have been nonspecific and incomplete. Studies using electroencephalographic methods have been fraught with subject sampling bias, a lack of standardized techniques and measures, and a lack of appropriate control groups. Low-functioning autistic children with age-matched normals, age-matched mentally handicapped, and mentally age-matched normal toddlers were tested using a computerized electroencephalographic technique. The autistic children showed significantly more slow wave activity and less alpha, as well as less inter- and intrahemispheric asymmetry than either normal or mentally handicapped children. In general, electroencephalographic features of autistic children closely resembled those of the toddlers, supporting a model of maturational lag as the key descriptor for autistic CNS functioning. A model of diminished cortical differentiation is proposed to account for the low level of intellectual functioning.

Organization in visual episodic memory: relationships between verbalized knowledge, strategy use, and performance.

Relationships between verbalized knowledge (metamemory), strategy use, and performance were examined in a memory task for visually presented episodes. Kindergarten, second-grade, and fifth-grade students were asked to reconstruct a sequence of pictures forming an episode from an array of original pictures and foils. The episodes varied on two dimensions; materials type and the logic of the sequence. Materials were either typical (familiar animal characters and scenes) or atypical (geometric figures) story materials. Sequences either readily conveyed a story (logical) or were rearranged to present a random ordering of pictures (illogical). Children were questioned about their use of a story line to help remember the picture sequences (general questioning) and were asked more specific questions concerning the reasons for their picture selection during the task (specific questioning). Children at all ages recalled logical sequences better than illogical ones. Second- and fifth-grade children recalled animal episodes better than geometric form episodes. Children at all ages showed a correspondence between strategy use and metamemory as assessed by verbalization of relationships among pictures during the specific questioning. However, when the more typical general question format was used to assess metamemory, strategy use preceded verbalized knowledge of strategy use.

Application of pattern evoked potential techniques for evaluating infant perceptual systems.

An evoked potential (EP) test was developed to aid in the diagnostic evaluation of a 16-week-old infant of initially unknown pathology and degree of perceptual deficit. Patterned stimuli were presented at two repetition rates to challenge the infant's visual and auditory information processing capabilities. The data were compared to those obtained from a "normal" infant of the same age and sex and, where possible, to normative population data. The EP data indicated the following: (1) the "suspect" infant's occipital response to visual pattern was abnormal in terms of waveform characteristics and in the relationship of its amplitude to spatial frequency of pattern; (2) in comparing brain response to 1 Hz and 6 Hz stimulation rates, the "suspect" infant's occipital EPs were abnormally attenuated for the faster presentation rate when a patterned visual display was part of the stimulus complex; (3) an auditory speech sound produced equivalent EP effects in both infants. These data indicated that the "suspect" infant's perceptual deficit was restricted to the processing of visual pattern information, possibly due to abnormal functioning of the geniculo-striate system. Subsequent tests and the diagnosis of ocular albinism corroborated the results of the abnormalities suggested by the EP procedure.