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J S Latimer

Publications and source records attributed to J S Latimer.

13 recordsLinked to original sources
PubMed2000

Inflammatory bowel disease in children and young adults: correlation of sonographic and clinical parameters during treatment.

OBJECTIVE: The objective of this study was to evaluate the sonographic findings of inflammatory bowel disease activity in children undergoing treatment. SUBJECTS AND METHODS: Eighty-eight sonograms were obtained of 23 bowel segments in 17 children and young adults (age range, 10-21 years; mean, 16 years) with new or recurrent inflammatory bowel disease. Sixteen segments were involved with Crohn's disease and seven with ulcerative colitis. Serial sonography (range, two to eight examinations; mean, four per segment) was performed while patients underwent treatment. Bowel wall thickness measurements and color and power Doppler sonography grading were recorded and compared with clinical data. RESULTS: All 17 patients had at least one abnormal bowel segment on initial sonography. The correlation was significant (p < 0.01). Agreement was 91% on direction of change over time between bowel wall thickness and Doppler grades, with 100% correlation between color and power Doppler sonography grades. In patients with Crohn's disease, the correlation was significant (p < 0.05) between bowel wall thickness and Doppler grades with two of seven and four of seven clinical parameters, respectively. In patients with ulcerative colitis, the correlation was significant (p < 0.05) between bowel wall thickness and Doppler sonography grades with four of seven and three of seven clinical parameters, respectively. The erythrocyte sedimentation rate correlated with all sonographic measurements in both patient groups. Combining bowel wall thickness and Doppler sonography, the percentage of agreement was significant in the direction of change, with five of seven clinical parameters in both patient groups. CONCLUSION: Gray-scale and color or power Doppler sonography can show changes in disease activity in children and young adults undergoing treatment for inflammatory bowel disease.

Adolescent↗
PubMed1998

Constitutive achlorhydria in mucolipidosis type IV.

Mucolipidosis type IV is an autosomal recessive lysosomal storage disease of unknown etiology that causes severe neurological and ophthalmological abnormalities. In an attempt to obtain insight into the nature of the metabolic abnormality in this disorder, we prospectively evaluated 15 consecutive patients, aged 2 to 23 years, over a period of 22 months. The finding of iron deficiency in some of the patients led us to the discovery that all patients but one had markedly elevated blood gastrin levels. None had vitamin B12 deficiency. Gastroscopy in three patients showed normal gross appearance of the mucosa in two patients, 4 and 7 years old, and mucosal atrophy in a 22-year-old. Parietal cells were present in normal numbers and contained large cytoplasmic inclusions that were confirmed immunohistochemically to be lysosomal in nature. Other gastric epithelial cells appeared normal. Parietal cells contained very few tubulovesicular membranes, suggesting cellular activation, whereas apical canaliculi appeared relatively nonactivated. Both subunits of the parietal cell H+/K+-ATPase were present, and both partially colocalized with f-actin at the apical membrane. We conclude that patients with mucolipidosis type IV are constitutively achlorhydric and have partially activated parietal cells. We hypothesize that the defective protein in this disease is closely associated with the final stages of parietal cell activation and is critical for a specific type of cellular vacuolar trafficking between the cytoplasm and the apical membrane domain.

Achlorhydria↗
PubMed1982

Sclerosing cholangitis associated with inflammatory bowel disease.

The asymptomatic course of two adolescents with hepatobiliary complications of inflammatory bowel disease are reported. As has previously been documented in adult patients, liver biopsy and cholangiography of the biliary tree are indicated procedures when the cholestatic enzymes are elevated in children with colonic involvement.

Adolescent↗
PubMed1980

Alpha-1-antitrypsin deficiency in childhood.

alpha 1AT deficiency predisposes children to liver injury and adults to emphysema. Pi typing has clarified that the inherited deficiency is codominant. Amniocentesis is unproved as a reliable technique in detecting the homozygous deficient patient (another controversial issue). Even if this procedure were to become diagnostic, present knowledge cannot predict the clinical course of each individual born with homozygous alpha 1AT deficiency, therefore confronting the physician and parents with a moral dilemma that neither of us feels comfortable with in regard to family counseling. Presently, we can only educate the family with the current state of the art summarized in this review. The fundamental steps in evaluating a child and the involved family are outlined in Table 2. Steps 1, 2 and 5 should be readily available. Pi typing can specifically identify susceptible individuals who can be counseled concerning work habits and known toxins such as smoking and alcohol. Liver biopsy is not essential for diagnostic purposes but may prove to be prognostic concerning the child's ultimate outcome. More certain is the evidence that no infant should be explored for a bile duct lesion during the early cholestatic period because no surgical lesion will be found. Therefore, all children with infantile cholestasis should be evaluated for alpha 1AT deficiency prior to a laparotomy. Although medical therapy is only supportive at the present time, further research should eventually provide therapeutic approaches to the basic defect.

Adolescent↗
PubMed1978

Theory of binaural interaction based on auditory-nerve data. III. Joint dependence on interaural time and amplitude differences in discrimination and detection.

This paper is primarily concerned with issues of symmetry-asymmetry in the joint dependence of binaural performance on interaural time delay and interaural amplitude ratio. The predictions of our model based on auditory-nerve data are shown to be inadequate for available data showing asymmetries in interaural time discrimination. Measured detection thresholds for a 500-Hz tone burst masked by wide-band noise are reported for nonunity amplitude ratios and both polarities of delays in order to test for asymmetries analogous to those observed in the time discrimination case. The detection results show only small asymmetries and are not inconsistent with the model. A general discussion of our model and the implications of available empirical results leads to a suggested modification of the model. We show by an example that modifications of the type we are suggesting are capable of describing the detection data and at least the gross trends of the discrimination data.

Auditory Perception↗
PubMedDate not supplied

Sucrase and cellular development.

The cellular changes that take place as the intestinal cell migrates from crypt to villus are morphologically and biochemically remarkable. It is fortunate that many of these phenomena can be delineated by following enzymic activities. Sucrase-isomaltase is a particularly fascinating enzyme complex because it is a marker of the differentiated cell. Sucrase is inducible with steroids and protected by the substrate sucrose. Purified enzyme can be used to stimulate production of specific antibodies in goats; these antibodies have been used as probes to locate enzymically active and inactive antigen in the cells of the crypt and villus respectively. Further examination of the enzyme has indicated a molecular weight of 200 000--350 000. These higher molecular weight components are located in the brush border of the enterocytes. Lower molecular weight subunits are antigenically active and are in the cytosol. It is assumed that these smaller components are enzymically inactive pre-combination subunits of the sucrase-isomaltase complex and that the sucrase-isomaltase of the brush border is an aggregate of these subunits. The California sea lion, which is deficient in intestinal sucrase activity, does have isomaltase activity. This finding supports the concept that there are different gene complexes for sucrase and for isomaltase.

Aging↗