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PubMed2001

Ocular findings among patients with late-diagnosed or poorly controlled homocystinuria compared with a screened, well-controlled population.

INTRODUCTION: Untreated homocystinuria (HCU) leads to systemic and ocular complications preventable by early treatment. METHODS: This study describes the ocular features in HCU patients who had late diagnosis or were noncompliant with treatment compared with a control group of early-diagnosed and well-controlled subjects. RESULTS: Fourteen late-diagnosed HCU patients with a median age at diagnosis of 4 years (range, 1.25-28 years) were studied. Five patients were born outside of Ireland or before screening began. All 14 patients had lens subluxation or dislocation at diagnosis. Only 28.6% of eyes had 20/40 vision or better. Three patients were tested for HCU following the diagnosis in a sibling. Four patients attended ophthalmology departments for a median of 12.8 years (range, 4-23 years) prior to diagnosis of HCU; all had steadily progressive myopic astigmatism and lens subluxation. Six patients who became poorly controlled in their teens or early twenties showed significant progression of their myopia, and 3 had phacodonesis or lens subluxation develop. All eyes in this group had 20/40 vision or better. Fifteen patients who were detected in the newborn period and remained well controlled had no evidence of lens subluxation. All of the control group patients had 20/20 vision bilaterally. The difference in visual acuity between late-diagnosed patients and the control group was highly significant (P =.0002). The differences in refractive errors between the groups were also highly significant (P =.0001). CONCLUSIONS: Lens subluxation is a principal feature of untreated HCU, yet we found a median lag period of 5.5 years in 4 cases before diagnosis. Young persons with marked and progressive myopia or idiopathic lens subluxation should be screened for HCU.

Adult↗
PubMed2000

[Salivary gland scintigraphy en Sjogren syndrome and its relation with the result of lip biopsy. Comparative study with a control population].

BACKGROUND: Salivary gland scintigraphy allows a non invasive, morphological and functional assessment of parotid and submaxillary salivary glands. AIM: To describe the main features of salivary gland scintigraphy in patients with Sjögren syndrome, rheumatic fibromyalgia and normal controls and compare the results with lip biopsy. PATIENTS AND METHODS: Sixty one normal controls, 66 patients with Sjögren syndrome and 18 patients with rheumatic fibromyalgia were studied. For the diagnosis of Sjögren syndrome and fibromyalgia rheumatica, the Modified European and American College of Rheumatology criteria were used, respectively. Lip biopsies were obtained in 52 patients with Sjögren syndrome. Scintigraphy was done with a gamma camera and computer after the administration of 99mTc-pertechnetate, obtaining images during 30 min and creating time/activity curves. Scintigraphy was classified as normal, with mild or severe alterations. RESULTS: Scintigraphy was normal in 74% of control subjects and in 26%, it had mild alterations. In 72% of patients with rheumatic fibromyalgia, scintigraphy was normal whereas in 28%, it had mild alterations. In 27% of patients with Sjögren syndrome, scintigraphy was normal, in 27% it had mild alterations and in 46%, severe alterations. There was a positive and significant correlation between pathological alterations of salivary glands and scintigraphic alterations (r = 0.642, p < 0.001). CONCLUSIONS: Severe scintigraphic alterations of salivary glands strongly support the diagnosis of Sjögren syndrome. Mild alterations are non specific and a normal scintigraphy does not exclude the diagnosis.

Adolescent↗
PubMed2002

Nutrition status in patients younger and older than 60 y at hospital admission: a controlled population study in 995 subjects.

OBJECTIVE: Body weight and body mass index are easily obtainable indicators of nutrition status but do not provide information on changes in fat-free mass (FFM) and fat mass with age. In this prospective controlled study, we investigated whether body composition measurements were useful in identifying moderately or severely depleted patients, as judged by the Subjective Global Assessment at hospital admission. In addition, the subjects were grouped by age (< or =60 and >60 y) to determine whether there was an effect of aging on the prevalence of malnutrition. METHODS: Nine hundred ninety-five consecutive patients were evaluated for malnutrition by body mass index, serum albumin, Subjective Global Assessment, and 50-kHz bioelectrical impedance analysis and compared with 995 age- and height-matched healthy volunteers for FFM and fat mass. RESULTS: A body mass index less than 20 kg/m(2) was found in 17.3% of patients. Low albumin (< or =34.9 g/L) was found in 14.9% of all patients and 23.7% of those older than 60 y. In contrast, 23.1% and 38.3% of all patients were severely and moderately depleted, respectively, according to the Subjective Global Assessment. FFM was significantly lower in severely depleted men and women and moderately depleted women (P < or = 0.001), and fat mass was significantly higher (P < or = 0.05) in well-nourished patients than in volunteers. Patients older than 60 y had lower FFM and higher fat mass than did patients 60 y or younger or volunteers (P < or = 0.001). CONCLUSION: The prevalence of malnutrition was greater in patients older than 60 y than in those 60 y and younger. Patients classified as severely depleted according to the Subjective Global Assessment were depleted of FFM. Body composition measurement can help to identify patients with low FFM and high fat mass.

Adipose Tissue↗
PubMed1983

Lymphocyte transformation to connective tissue antigens in adult and juvenile rheumatoid arthritis, osteoarthritis, ankylosing spondylitis, systemic lupus erythematosus, and a nonarthritic control population.

Transformation of peripheral blood lymphocytes after exposure to connective tissue antigens was measured in patients with adult (n = 35) and juvenile rheumatoid arthritis (n = 34), osteoarthritis (n = 21), ankylosing spondylitis (n = 15), and systemic lupus erythematosus (n = 26) and in control subjects (n = 36). The connective tissue antigens included homologous cartilage-type proteoglycan, cyanogen bromide-derived peptides of type I, II, and III collagens, and type I and II helical collagens. Lymphocyte transformation was not detected in the osteoarthritic and control groups, with one exception. Sensitization to at least one connective tissue antigen was detected in approximately one-third of the rheumatoid arthritic and lupus patients and in one-quarter of the juvenile rheumatoid patients. In ankylosing spondylitis, positive responses occurred to proteoglycan in 20% of patients tested but never to collagens or peptides. Sensitivity to proteoglycan was detected only in ankylosing spondylitis except for one patient with juvenile rheumatoid arthritis. In patients with systemic lupus erythematosus and both forms of rheumatoid arthritis, lymphocyte transformation was usually more frequently detected to peptides than to the helical collagens. In adult rheumatoid arthritis, type II peptides elicited an elevated number of responses (14%) as did type I (9%) and III (8%) peptides to lesser degrees. Responses to type I (4%) and II (4%) helical collagens were infrequent. Rheumatoid arthritic patients usually exhibited sensitivity to only one antigen and lymphocyte transformation was often detected when the arthritis was improving. In juvenile rheumatoid arthritis, lymphocyte transformation was detected to peptides of type I (16%), II (9%), and III (29%) collagens and to helical type I (12%) and II (8%) collagens. In systemic lupus erythematosus, sensitization was detected to peptides of type I (13%), II (20%), and III (14%) collagens and to helical type I collagen (18%) but not type II collagen. Simultaneous sensitivity to several antigens often occurred in both systemic lupus erythematosus and juvenile rheumatoid arthritis. Examination of individual patients in all three rheumatic disease groups revealed that immune sensitivity developed to collagen peptides rather than to the helical molecules, particularly in the case of type II collagen. Thus, some patients with inflammatory arthritis exhibit immune responses to connective tissue components which are, as a group, characteristic for each type of arthritis. These responses, which were not obviously associated with disease activity, may develop as a result of inflammation or trauma which destroys connective tissue and exposes molecules, in either a native or degraded state, to cells of the immune system. Expression of sensitivity to these tissue antigens may contribute to the chronicity of the inflammatory arthritides.

Adult↗
PubMed1993

Hepatic morphology and iron quantitation in perinatal hemochromatosis. Comparison with a large perinatal control population, including cases with chronic liver disease.

We compared hepatic morphology, hepatocellular siderosis, extrahepatic parenchymal siderosis, and (by chemical assay of liver and spleen) the amount of elemental iron and copper in 12 cases of perinatal hemochromatosis (PH) with 119 perinatal controls. Controls were subgrouped according to diagnoses based on clinical and autopsy findings; 37 had chronic liver disease, either hepatic fibrosis (17) or cirrhosis (20). Graded semiquantitatively, hepatocellular siderosis varied widely among controls, and some showed more than PH cases. By chemical assay, total hepatic iron in PH cases was not significantly greater than in any control group except the preterm. Therefore, our findings do not support an etiological role for iron in PH. Its distinctive hepatic morphology seems related to onset of liver disease during fetal life, when periportal hepatocytes normally contain hemosiderin (as in 71 of 82 controls without chronic liver disease). Environmental agents (such as hypoxia, virus, drug) that could damage a fetal liver would usually damage other fetal organs as well. They would be unlikely to recur in a subsequent pregnancy and thereby account for PH occurring in siblings. In initiating PH, therefore, putative environmental agents may need to interact with a factor or factors intrinsic to the developing fetal liver.

Chronic Disease↗
PubMed1989

Models to assess the potential of Capillaria hepatica to control population outbreaks of house mice.

Population outbreaks of house mice (Mus domesticus) occur periodically in the wheatlands of southeastern Australia. This paper uses mathematical models to assist in the evaluation of the potential of a nematode, Capillaria hepatica, as a biological control agent to reduce the severity of these 'plagues'. C. hepatica is unique amongst helminths of mammals in that its eggs are released only upon the death of an infected host. The major goal of the modelling in this paper is to determine the impact of this feature on the population dynamics of the host-parasite interaction. Simple differential equation models are used to examine the general properties of the system and determine which population parameters are most crucial to the outcome of the interaction. These models are supplemented by age-structured models which investigate the initial behaviour of the system after introduction of the parasite. The necessity of host death for transmission is a strongly destabilizing factor, suggesting that C. hepatica cannot regulate most populations stably in the absence of strong resource limitation, although it has the potential to depress mouse populations below infection-free levels. Although C. hepatica influences mouse fecundity at lower burdens than it affects mortality, the age-structured models show that parasite-induced host death cannot be neglected. Because transmission requires host death, the parasite life-cycle operates on a time-scale similar to that of the hosts, and introduction of the parasite as early as possible in the development period of an outbreak will therefore be necessary to achieve substantial reductions in plague intensity.

Animals↗
PubMed1980

Determination of urinary mandelic and phenylglyoxylic acids in styrene exposed workers and a control population.

Styrene is rapidly metabolized in humans to mandelic () and phenylglyoxylic acids (P) which are excreted in urine. The present study investigates a gas chromatographic technique for measuring urinary concentrations of MA and PGA of workers exposed to styrene, compares the urinary concentrations of metabolites with time-weighted average air exposures to styrene and determines the levels of these metabolites in a population of workers not exposed to styrene. Post-shift urine specimens were obtained from a group of workers exposed to styrene in the reinforced plastic industry and from a control group. High positive correlation was found between post-shift urinary concentrations of metabolites and 8-hour TWA styrene exposure. Both MA and total metabolites (MA + PGA) gave correlation coefficient values of 0.96, p less than 0.0001. The mean MA excretion for the control groups was 6 mg/L. Determination of the concentration of these metabolites in a post-shift urine provides an effective means of estimating and monitoring human exposure to styrene.

Air Pollutants, Occupational↗
PubMed1982

Full crown restorations and gingival inflammation in a controlled population.

The volume of crevicular fluid around full crown restorations was measured with a Periotron instrument to compare the gingival inflammation between restored and nonrestored teeth in the same patient. Thirty-eight full crown restorations were compared to nonrestored teeth used as controls in 26 patients. Forty-six full crown restorations in 28 patients were also evaluated according to gingival margin placement to determine if there was a difference in inflammation in gingival tissues. The highly motivated patients were selected from a private practice because of their interest and investment in long-term dental health. The results revealed the following findings. 1. Full crown restorations have the potential for causing gingival inflammation. However, they need not be associated with a significant increase in gingival inflammation when placed in the oral environment of a highly motivated patient in a rigid dental recall program. 2. Gingival inflammation surrounding full crown restorations may be controlled regardless of gingival margin placement when the gingiva is healthy, the restorations are adequate, and the patient is in a strict recall program.

Adult↗
PubMed2004

The glutathione S-transferase polymorphisms in a control population and in Alzheimer's disease patients.

In this study, we investigated the role of glutathione S-transferase P1 (GSTP1) polymorphisms in the pathogenesis of Alzheimer's disease (AD). We genotyped the GSTP1 polymorphisms in exon 5 (A313G) and exon 6 (C341T) by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 56 Croatian patients with AD and 231 controls. Distributions and frequencies of GSTP1 genetic variants were not statistically different between AD patients and healthy controls. Higher frequencies of the mutant genotypes were observed in AD patients (13% for both A313G and C341T) when compared with control subjects (7% for A313G and 8% for C341T), but association of GSTP1 GG (OR 2.057, 95% CI 0.796-5.315, p=0.094) and TT (OR 1.691, 95% CI 0.669-4.270, p=0.514) genotypes with an increased risk of AD was not confirmed by statistical analysis. The frequencies of GSTP1 alleles (A, B, C, D) did not significantly differ between AD patients and controls and they were indicated as follows: 52.7%, 15.2%, 12.5% and 19.6% for AD cases and 58.4%, 14.1%, 14.1% and 13.4% for controls. The estimation of the GSTP1 haplotype distribution showed that GSTP1*A/GSTP1*B and GSTP1*A/GSTP1*C haplotypes were less frequent, while GSTP1*B/GSTP1*B and GSTP1*C/GSTP1*D haplotypes were more frequent in AD patients than in controls. In conclusion, the involvement of GSTP1 alleles in individual susceptibility to AD was not confirmed as statistically significant in the tested Croatian Caucasian population. A possible role of GSTP1 in the complex etiopathogenesis of AD is further discussed, based on observed differences in haplotype distribution and higher frequencies of mutant genotypes in AD patients.

Adolescent↗