The oral health of disadvantaged adolescents in North York, Ontario

Disadvantaged youth such as the homeless, the unemployed or recent immigrants are thought to be at high risk for dental problems, but data to support this hypothesis are rare. Using interviews and clinical examinations, this study measured the oral health status and treatment needs of a convenience sample of 478 disadvantaged adolescents aged 14 and older in North York, Ontario. Although the results cannot be generalized to the overall population, the data suggested that disadvantaged youth have high rates of oral disease. The adolescents reported a variety of symptoms, including oral pain and low rates of dental visiting. Clinically, high rates of periodontal disease, dental decay and urgent treatment needs were detected. If public health resources are to be directed to those most in need, efforts should be made to identify high-risk groups that may be overlooked in general surveys. Prevention, detection and treatment programs should be considered for high-risk adolescents.

Patterns of and reasons for tooth extractions in general dental practice in Ontario, Canada

While substantial proportions of the population of Ontario, Canada continue to have teeth extracted, little is known about the reasons for this loss. In this survey of Ontario general dental practitioners, 128 dentists provided information on 6143 patients they saw during a reference week. Approximately one-in-seven of these patients had or were going to have one or more extractions as part of their current course of treatment. The mean number of extractions for patients having at least one tooth taken out was 2.3 (SD = 2.5). Emergency patients were more likely than regular patients to have at least one extraction but, on average, had fewer teeth taken out. Orthodontic considerations were the main reason for tooth loss in childhood, caries continued to be an important cause of tooth loss at all ages and periodontal disease accounted for more teeth lost after 40 years of age than caries. This study differs from almost all others in finding that, overall, more permanent teeth were extracted because of periodontal disease than because of caries. The former accounted for 35.9% of teeth lost and the latter for 28.9%. While this may be due to methodological differences between this and other studies, it is consistent with epidemiological data on periodontal disease in the Ontario population and data showing that Ontarians receive little in the way of periodontal care.

Pain and the quality of life in patients referred to a craniofacial pain unit

Although there are reasons to believe that temporomandibular disorders and other facial pain conditions would have a major impact on the quality of patients' lives, only a small number of studies have attempted to address this in a systematic way. In this study, data on pain and its consequences were assessed for 121 patients making their first visit to a craniofacial pain research unit. The extent to which musculoskeletal and neurologically based facial pain compromised the quality of life was measured using the Oral Health Impact Profile, a recently developed index of the functional and psychosocial outcomes of oral conditions. The data indicated that facial pain had a substantial impact on daily life and that its most common outcomes were psychologic. When compared with a nonpain population, the extent of this impact was striking. There was a four-fold increase in functional problems such as difficulty chewing foods and a nine-fold increase in reports of depression. As anticipated, scores on the Oral Health Impact Profile were associated with the characteristics of the pain and diagnostic subgroups.

Immunocytochemical studies of an antigen in a human T-cell lymphoma line (Jurkat) recognized by certain monoclonal antibodies to CD-13 (aminopeptidase-N)

The immunofluorescent staining of Jurkat cells by a panel of eight CD-13 monoclonal antibodies has been investigated. With unfixed cells all antibodies were negative, in contrast to the CD-13-positive cell line, HL60, which gave staining in each case. These results were in line with our previous enzymological studies in which we showed that the aminopeptidase activity observed with intact Jurkat cells was located in the cytoplasm and was distinct in properties from aminopeptidase-N (CD-13), which is expressed by HL60 cells. After fixation of Jurkat cells, four antibodies, 22A5; MCS-2, 72a and WM-15, gave consistent positive staining, while the other four, WM-47, RMAG6, MY7 and CLB-mon-gran/2 were consistently negative. Prior fixation was an absolute requirement for staining, but was observed over a range of concentrations of paraformaldehyde from 0.4% to 4%, as well as with acetone or methanol/acetic acid. Confocal fluorescence microscopy confirmed that the positive fluorescence given by 22A5 was located in the cytoplasm, contrasting with that given by an antibody to a cell-surface marker, HLA-DR, which was associated with the plasma membrane. The fixatives thus appeared to have rendered the cells permeable to the antibodies, but the molecular size of the antibodies could not explain the different behaviour of the two classes of antibodies, since IgG1 isotypes were present in both positive and negative groups. We exclude the possibility that Jurkat cells express an intracellular form of aminopeptidase-N; the identity of the protein(s) bearing the epitope(s) to which four of the antibodies bound has yet to be determined.

Measurements of blood pressure, oedema and proteinuria in a pregnant population of New Zealand

This is the first report of the largest study of blood pressure measurement in pregnancy in a New Zealand population using standardized definitions and methodology. Over 3,800 women who delivered in an 8-month period in the Wellington region were included in the study. Blood pressure measurement and the presence of oedema and proteinuria were recorded from booking until delivery and in the puerperium. Only 2.7% of women were unable to be contacted after delivery for details on outcomes. The results established normal ranges for blood pressure throughout pregnancy. The data show that blood pressure greater than 140/90 until 35 weeks' gestation is outside 2 standard deviations at all gestations and justifies using these measurements as the definition of hypertension in pregnancy. The fall in blood pressure in the 2nd trimester was less than 1 mm Hg per week in both the systolic and diastolic pressures. This fall was smaller than previously recorded in other studies. Gestational hypertension was the commonest blood pressure abnormality occurring in 15.2% of the population. This represented 69% of the pregnant women with a hypertensive disorder. The overall incidence of both gestational hypertension and preeclampsia was 18.5% which is higher than reported in other parts of the world. In this study obesity was significantly associated with hypertensive disorders in pregnancy. An arm circumference of > 33 cm, one of the measurements of obesity, was found in 6.8% of the study population. Even after the effect of arm circumference was taken into account, hypertensive disorders were also more common in Pacific Island women.(ABSTRACT TRUNCATED AT 250 WORDS)

The aminopeptidase activity in the human T-cell lymphoma line (Jurkat) is not at the cell surface and is not aminopeptidase N (CD-13)

Although lymphocytes are CD-13-negative and therefore should not express the ectoenzyme aminopeptidase N (AP-N), there have been a number of reports suggesting the presence of a cell-surface aminopeptidase with many similarities to AP-N. We have determined aminopeptidase activity with 4-methyl-7-coumarylamide (NMec) derivatives of alanine, leucine, lysine and arginine in Jurkat cells (a human T-cell lymphoma line) and in HL60 cells (a CD-13-positive myeloid leukaemia line) and compared the activities with those of purified pig AP-N and human renal microvillar membranes. Jurkat cell aminopeptidase activity doubled on disrupting the cells and the sensitivity to amastatin increased. When the cells were fractionated only 4% of the activity was recovered in the membrane fraction, compared with 87% recovery for alkaline phosphatase. The profile of activities for intact Jurkat cells was Leu > Ala > Lys > Arg, changing in the cytosolic fraction to Lys > or = Arg > Leu = Ala; the profiles for intact HL60 cells and AP-N were identical, namely Ala > Leu > Arg > Lys. The Km values for the hydrolysis of Ala-NMec and Leu-NMec by Jurkat cells were 65 microM and 11 microM, in each case some 6-fold lower than those for AP-N. The pH-activity curves for the hydrolysis of Ala-NMec by Jurkat cells and human renal microvillar membranes were displaced by almost 1 pH unit and the activity was not sensitive to the anionic composition of the buffers. However, a 3-fold activation of the cytosolic activity by 0.1 M NaCl was observed with Arg-NMec as substrate. With Ala-NMec as substrate, the sensitivity of the aminopeptidase activity to inhibitors increased markedly after disrupting the cells, but still differed from that observed with purified pig AP-N; the concentrations giving 50% inhibition were as follows (values for AP-N in parentheses): amastatin. 28 nM (150 nM); bestatin, 12 microM (43 microM), probestin, 100 nM (< 10 nM), puromycin, 30 microM (> 1 mM). Anion exchange chromatography on Mono Q revealed two activities: that of peak I preferentially hydrolysed Arg-NMec, was activated by NaCl and was insensitive to amastatin; while that of peak II was strongly inhibited by amastatin and had a broad specificity.(ABSTRACT TRUNCATED AT 400 WORDS)

An assessment of the use of meconium alone as an indication for fetal blood sampling

OBJECTIVE

To assess the validity of meconium as an indication for fetal blood sampling.

METHODS

The study design was a prospective observational study in a teaching hospital. Fetal blood samples were taken from 401 women. One hundred sixty-five patients had meconium-stained amniotic fluid (77 of whom had no cardiotocographic abnormalities). In the remaining 236 patients, the indication for fetal blood sampling was cardiotocographic abnormalities without meconium. The main outcome measures were the values of pH and base excess obtained at fetal blood sampling, 1-minute Apgar scores, and umbilical artery pH values.

RESULTS

Patients with meconium alone as an indication for fetal blood sampling had higher scalp sample pH values (P < .001) and 1-minute Apgar scores (P < .01) than laboring patients with both meconium and cardiotocographic abnormalities. The patients with meconium alone had higher scalp pH values than patients with cardiotocographic abnormalities but no meconium (P < .001). In only two patients with meconium alone was a fetal scalp pH less than 7.20 (both infants had good Apgar scores at delivery). However, when cardiotocographic abnormalities were present, the finding of meconium was significant, resulting in lower 1-minute Apgar scores (P < .01) despite a lack of difference in fetal blood sample pH values.

CONCLUSION

In the absence of cardiotocographic abnormalities, meconium is not an indication for fetal blood sampling.

Changes in the PR, RR intervals and ST waveform of the fetal lamb electrocardiogram with acute hypoxemia

The PR and RR intervals and T wave amplitude of the fetal lamb electrocardiogram were studied during acute hypoxemia produced by reduction of the maternal placental blood flow. Five chronically-instrumented fetal lambs (124 to 143 days of gestation) were subjected to acute hypoxemia (observations = 13) through complete occlusion of the maternal aorta for 60 s. The fetuses responded to the occlusion with a fall in oxygen tension (2.18 +/- 0.12 kPa to 1.11 +/- 0.14 kPa, SEM, P < 0.001) and oxygen saturation (48 +/- 4% to 19 +/- 4%, P < 0.001). Modest changes of pH (7.37 +/- 0.05 to 7.35 +/- 0.01, p), carbon dioxide tension (5.79 +/- 0.15 kPa to 6.17 +/- 0.14 kPa, P < 0.001) and plasma lactate concentration (2.1 +/- 0.6 mmol/l to 2.2 +/- 0.6 mmol/l, ns) occurred. The PR interval showed a triphasic pattern following occlusion. Initially, and simultaneously with the onset of the RR interval lengthening, a prolongation of the PR interval occurred (P < 0.01) with a peak value after 41 +/- 3 s after occlusion. Following this transient prolongation, the PR interval shortened concurrently with a maximum lengthening of the RR interval (P < 0.001) 2 +/- 3 s after the end of the occlusion. A maximum PR shortening (P < 0.001) occurred 27 +/- 5 s after occlusion followed by a prolongation of the PR interval (P < 0.001) with a peak value 203 +/- 21 s after release of the occlusion.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of callus removal on dynamic plantar foot pressures in diabetic patients

Clinical observation suggests that neuropathic foot ulceration frequently occurs beneath plantar callosities and in areas of high dynamic shear and vertical stress underneath the foot during walking. Seventeen diabetic patients had dynamic foot pressure measurements made before and after the removal of a total of 43 forefoot plantar callosities. Peak pressures (mean +/- SE) in the treated areas were reduced by 26% from 14.2 +/- 1.0 to 10.3 +/- 0.9 kg cm-2 (p less than 0.001), with reductions at 37 of the 43 sites and in all patients. Mean heel pressures were not significantly different (5.0 +/- 0.6 vs 4.9 +/- 0.6 kg cm-2). These results suggest that callus may act as a foreign body elevating plantar pressures and that a significant reduction in pressure is achieved by local chiropody treatment.

A highly sensitive E.L.I.S.A. for endopeptidase-24.11, the common acute-lymphoblastic-leukaemia antigen (CALLA, CD-10), applicable to material of porcine and human origin

Endopeptidase-24.11 is a widely distributed cell-surface enzyme with a key role in the metabolism of neuropeptides. It is now known to be identical with CD-10, the common acute-lymphoblastic-leukaemia antigen (CALLA). An e.l.i.s.a. is described which utilizes two antibodies, one monoclonal, the other polyclonal, generated to pig endopeptidase-24.11. These antibodies cross-reacted with human endopeptidase-24.11, thus making the assay applicable to both species. By using optimum conditions for the e.l.i.s.a., as little as 25 pg of pure pig endopeptidase-24.11 could be quantified at 95% confidence limits. E.l.i.s.a. of tissue homogenates from a variety of pig tissues and of human kidney correlated well with enzymic assays. However, the use of detergents to solubilize the antigen greatly decreased the sensitivity of the e.l.i.s.a. The e.l.i.s.a. is 1000-fold more sensitive than the immunoradiometric assay and has advantages in specificity over enzymic assays. Daudi cells, some leukaemic cells shown to be CALLA-positive, and Caco-2 cells, could also be assayed, but N2 cavitation was necessary to fragment the cells, and only part of the total endopeptidase-24.11 activity in Daudi cells was recognized by the e.l.i.s.a.