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F Connell

Publications and source records attributed to F Connell.

7 recordsLinked to original sources
PubMed1992

Variability in the clinical and pathological findings in the neuronal ceroid lipofuscinoses: review of data and observations.

We reviewed the clinical and pathological data on 319 neuronal ceroid lipofuscinosis (NCL) cases to determine the degree of variability within the different forms and among and within families. Thirty-six cases (11.3%) were the infantile form; 116 cases (36.3%), late infantile; 163 cases (51.1%), juvenile; and four cases (1.3%), the adult form (Kufs disease). Clinical variability was found in all forms studied, but was most striking in the juvenile and late infantile forms of NCL. The expected initial findings of seizures, dementia, blindness, or motor impairment were evident in 255 cases (80%), and rarer, less typical initial neurological symptoms were seen mainly in the 64 cases (20%) of the juvenile form: behavior abnormalities (18/64), psychoses (12/64), neuropathy (2/64), involuntary movements (15/64), ataxia (9/64). Six juvenile and two adult cases had no detectable impairment of vision. All 319 NCL cases had skin or conjunctive biopsies or buffy coats that showed the characteristic ultrastructural abnormalities of NCL. Variability was evident in 16.7% in that a combination of fingerprint, curvilinear, and membranous profile inclusion bodies was observed in storage lysosomes, although one type of inclusion was distinctly predominant for each form. Postmortem examination of brains of 19 NCL cases (three with the infantile form, six with the late infantile form, nine with the juvenile form, and one with the adult form) revealed characteristic changes. Sixteen of the 19 NCL brains (84%) showed pathological variability in that they contained more than one kind of characteristic inclusion body in the neuronal lysosomal storage compartment. In all 19 NCL brains, small amounts of aging lipofuscin were also found.(ABSTRACT TRUNCATED AT 250 WORDS)

Amyloid beta-Protein Precursor↗
PubMed1991

Referral keeping in homeless women.

We examined factors associated with referral keeping among 118 homeless women screened for health care needs in Seattle. Referral keeping for medical conditions among the homeless was comparable to rates found in general low-income populations (62 percent vs. 65 percent), but their proportion of kept referrals for preventive care was much lower (22 percent vs. 44-51 percent). Referral keeping varied directly with symptom severity. Consistent with this finding was that among interviewed subjects who did not keep the index referral, 37 percent kept other referrals for more severe problems or if the condition worsened. Personal stresses and competing priorities, weighted against perceived medical urgency, were the major factors influencing referral keeping. Screener encouragement and communication of medical urgency were indicated by one-third of the subjects who kept referrals as providing important motivation for treatment.

Adult↗
PubMed1990

What is too much variation? The null hypothesis in small-area analysis.

A small-area analysis (SAA) in health services research often calculates surgery rates for several small areas, compares the largest rate to the smallest, notes that the difference is large, and attempts to explain this discrepancy as a function of service availability, physician practice styles, or other factors. SAAs are often difficult to interpret because there is little theoretical basis for determining how much variation would be expected under the null hypothesis that all of the small areas have similar underlying surgery rates and that the observed variation is due to chance. We developed a computer program to simulate the distribution of several commonly used descriptive statistics under the null hypothesis, and used it to examine the variability in rates among the counties of the state of Washington. The expected variability when the null hypothesis is true is surprisingly large, and becomes worse for procedures with low incidence, for smaller populations, when there is variability among the populations of the counties, and when readmissions are possible. The characteristics of four descriptive statistics were studied and compared. None was uniformly good, but the chi-square statistic had better performance than the others. When we reanalyzed five journal articles that presented sufficient data, the results were usually statistically significant. Since SAA research today is tending to deal with low-incidence events, smaller populations, and measures where readmissions are possible, more research is needed on the distribution of small-area statistics under the null hypothesis. New standards are proposed for the presentation of SAA results.

Age Factors↗
PubMed1987

Phospholipid metabolism in mouse sciatic nerve in vivo.

To probe the activities of various pathways of lipid metabolism in peripheral nerve, six phospholipid-directed precursors were individually injected into the exposed sciatic nerves of adult mice, and their incorporation into phospholipids and proteins was studied over a 2-week period. Tritiated choline, inositol, ethanolamine, serine, and glycerol were mainly used in phospholipid synthesis; in contrast, methyl-labeled methionine was primarily incorporated into protein. Phosphatidylcholine was the main lipid formed from tritiated choline, glycerol, and methionine precursors. Phosphatidylserine, phosphatidylethanolamine, and phosphatidylinositol were the main lipids formed from serine, ethanolamine, and inositol, respectively. With time there was a shift in label among phospholipids, with higher proportions of choline appearing in sphingomyelin, glycerol in phosphatidylserine, ethanolamine in phosphatidylethanolamine (plasmalogen), and inositol in polyphosphoinositides, especially phosphatidylinositol 4,5-bisphosphate. We suggest that the delay in formation of these phospholipids, which are concentrated in peripheral nerve myelin, may, at least in part, be due to their formation at a site(s) distant from the sites where the bulk of Schwann cell lipids are made. We propose that separating the synthesis of these myelin-destined lipids to near the Schwann cell's plasma membrane would facilitate their concentration in peripheral nerve myelin sheaths. At earlier labeling times, ethanolamine and glycerol were more actively incorporated into phosphatidylcholine and phosphatidylinositol, respectively, than later. The transient labeling of these phospholipids may reflect some unique role in peripheral nerve function.

Animals↗
PubMed1985

Adult fragile X syndrome. Clinico-neuropathologic findings.

Fragile X syndrome [fra (X)] is currently accepted as the second most frequent chromosomal disorder associated with developmental disability. Although next to Down syndrome in frequency, no postmortem studies of confirmed adult cases had been reported. The autopsy examination of a 62-year-old, moderately retarded man with the fra (X) syndrome confirmed the preferential involvement of cerebral and testicular structures in this disorder. Dendritic spine abnormalities of the type observed in trisomic chromosomal disorders were associated with synaptic immaturity. Severe testicular hypogonadism accompanied bilateral macro-orchidism, normal penis, and unilateral hydrocele. Valvular, articular, and testicular interstitial compartments showed normal histochemical staining characteristics for glycoproteins and lipids.

Brain↗
PubMed1979

Remyelination in multiple sclerosis.

Chronic plaques in central nervous system tissue fixed by in situ perfusion for electron microscopy were examined for evidence of remyelination in 2 patients with multiple sclerosis (MS). Fibers with abnormal central myelin sheaths of several types were found at the margins of most of the plaques studied. The most common of these were: (1) the presence of bare stretches of axon between contiguous internodes, (2) the presence of thin paranodes, (3) internodes which changed markedly in thickness along their length due to premature termination of superficial or deep myelin lamellae that ended as hypertrophic lateral loops, and (4) abnormally thin internodes which were of uniform thickness along their length, which were shorter than normal, and which terminated in the form of normal nodal complexes. The finding of internodes of the last type at the edges of many plaques indicates that remyelination by oligodendrocytes can occur in the adult human CNS and that it is common in some cases of MS, although limited in its extent.

Central Nervous System↗