A comparison of calcaneus ultrasound and dual X-ray absorptiometry in healthy North American youths and young adults

Quantitative ultrasound is the newest noninvasive method to be accepted for assessing bone mineral in adults. Heel ultrasound measurements correlate with bone density measurements by dual X-ray absorptiometry (DXA) and predict fracture risk in adults. Far less is known about the value of calcaneus ultrasound (CUS) in children. We determine spine, femoral neck, and whole-body bone mineral by DXA and heel bone mass by CUS in 125 youths (69 females, 56 males) ages 9-25 yr. CUS and DXA measurements of bone mass increased with age and pubertal development during adolescence in a parallel fashion. Among females, Tanner stage was a stronger predictor than age for all CUS and DXA measurements, and among males, pubertal stage was a stronger predictor for spine bone mineral apparent density (BMAD) and femoral bone mineral density (BMD). CUS measurements correlated moderately well with DXA measurements of the spine, femoral neck, and whole-body BMD and spine BMAD (r = 0.23-0.58, p < 0. 008). CUS warrants further study as a tool for assessing bone mineral acquisition in children.

Influence of pre-adolescent diet on quantitative ultrasound measurements of the calcaneus in young adult women

Nongenetic determinants of quantitative ultrasound (QUS) properties of the bone remain to be identified. The purpose of this study was to determine relationships between early adolescent diet and QUS bone measurements taken in young adulthood. Subjects were participants in the 10-year longitudinal National Heart, Lung, and Blood Institute Growth and Health Study (NGHS). QUS parameters measured at the calcaneus in a convenience subsample of 63 18- to 19-year-old black and white women were correlated with dietary data collected when the subjects were aged 9-11 years. We hypothesized that pre-adolescent intake of calcium, magnesium, vitamin C and protein, nutrients known to be associated with bone development, would be associated with QUS measurements in young women. Stepwise multiple regression analysis, controlling for race, height and weight, demonstrated that pre-adolescent intake of calcium and magnesium were positively related to QUS parameters (calcium with broadband ultrasound attenuation, and magnesium with speed of sound and bone velocity). Our findings suggest that pre-adolescent diet may be associated with bone properties as measured by ultrasound. Further investigations of this relationship may yield a deeper understanding of the impact of diet on skeletal development. The small size of the convenience sample used for the analysis precludes stronger inferences at this time.

Position of poly(methyl methacrylate) and silicone intraocular lenses after phacoemulsification

PURPOSE

To compare the positional change of poly(methyl methacrylate) (PMMA) and silicone intraocular lenses (IOLs) in vivo after phacoemulsification.

SETTING

Taipei Municipal Yang-Ming Hospital, Taipei, Taiwan.

METHODS

A prospective study of 70 cataractous eyes treated by phacoemulsification with IOL implantation was carried out. The eyes were randomized into 2 groups based on IOL type: 1-piece PMMA IOL; 3-piece silicone IOL. The amount of IOL tilt and decentration was measured and anterior chamber depth (ACD) determined by Scheimpflug photography using an anterior eye segment analysis system (EAS-1000, Nidek). All eyes were examined 1 week and 1 to 6 months after surgery.

RESULTS

No statistically significantly differences were found in the amount of tilt and decentration between 2 IOL types throughout the study. The ACDs were relatively constant in both groups through the early postoperative periods.

CONCLUSION

The stability of PMMA and silicone IOLs were the same after phacoemulsification.

Bone acquisition and loss in children and adults with cystic fibrosis: a longitudinal study

OBJECTIVES

To determine patterns of bone mineral acquisition in children and young adults with cystic fibrosis (CF) and to identify clinical and laboratory correlates of change in bone mineral density (BMD).

STUDY DESIGN

Bone mineral and clinical status were assessed in 41 patients with CF (26 female, aged 9 to 50 years) at baseline and 1.5 years later. Bone mineral content of the lumber spine, femoral neck, and whole body was determined by dual-energy x-ray absorptiometry and expressed as BMD and bone mineral apparent density (BMAD). Changes in weight, height, pubertal status, glucocorticoid use, physical activity, disease severity, and biochemical markers of bone turnover were examined for associations with changes BMD and BMAD.

RESULTS

Mean BMD Z-scores (adjusted for age and sex) were reduced at the spine, hip, and whole body at baseline in both adults and youths, and decreased further at all sites among youths at follow-up (-0.4 at spine, p < 0.05; -0.3 at hip, p < 0.10; -0.5 for whole body, p < 0.0005). These data indicate failure to gain bone mineral at the expected rate. BMAD was also reduced at follow-up, suggesting that the observed osteopenia could not be explained by small bone size. Bone loss at multiple sites was observed in four youths and two adults. In general glucocorticoid use, change in body mass, physical activity, and disease severity were the most significant correlates for change in BMD and in BMD Z-score.

CONCLUSIONS

Osteopenia in CF generally reflects inadequate gains in bone mineral, although bone loss may occur, particularly in patients requiring glucoc therapy. Late gains in bone mineral may accompany weight gain and pubertal development, but the catch-up appears to be incomplete.

Two measures of physical activity as predictors of bone mass in a young cohort

OBJECTIVE

To compare the association of two measures of physical activity with bone mass in healthy children and young adults, as part of a larger study on bone mineral acquisition in youth.

DESIGN

Cross-sectional observation study.

SETTING

General community, outpatient study.

PARTICIPANTS

Subjects included 103 non-Hispanic white female (n = 54) and male (n = 49) healthy volunteers aged 9 to 25 years.

MAIN OUTCOME MEASURES

Self-reported physical activity was measured by a 3-day activity diary of all activities and a questionnaire designed to capture recreational activities throughout the year. Activity was expressed as hours per week of weight-bearing and non-weight-bearing activity. Bone mass at the hip, spine, and whole body was measured by dual x-ray absorptiometry.

RESULTS

The activity measures were not well correlated with each other. In males, weight-bearing and non-weight-bearing activity reported in 3-day diaries was positively associated with bone mass at the hip, spine, and whole body (p < 0.05). Among females, only weight-bearing activity measured by the yearly questionnaires was significantly positively associated with bone mass (p < 0.05). In males and females, weight-bearing activity was more highly correlated with bone mineral than was non-weight-bearing activity. In addition, the associations between activity and bone mass varied by skeletal site.

CONCLUSIONS

The association between physical activity and bone mass varied both in direction and in significance depending on the physical activity instrument used. Gender differences were observed in the associations between specific activity instruments, type of activity (weight-bearing and non-weight-bearing), and bone mass at different skeletal sites. Variability associated with the two physical activity measures may contribute to discrepant findings in this study and in the literature.

Evidence for the participation of the proteasome and calpain in early phases of muscle cell differentiation

Objectives were to investigate the role of the proteasome and m-calpain to muscle cell differentiation. Accordingly, we investigated the effects of lactacystin, a proteasome inhibitor, and calpain inhibitor-II (CI-II) on L8 muscle cell differentiation and assessed concentrations of proteasomal and calpain subunit mRNAs during differentiation. L8 myoblasts were induced to differentiate by culturing in mitogen-depleted medium. To assess the importance of the proteasome and calpain to differentiation, we examined effects of lactacystin and CI-II on creatine kinase (CK) activity. In the absence of inhibitor, CK activity was detectable within 48 h of mitogen depletion and myotubes were formed. Addition of lactacystin or CI-II to cultures drastically reduced CK activity and prevented formation of myotubes. Hence, proteasome and calpain are both necessary for differentiation. In order to identify which proteasomal subunits were regulated during differentiation, we examined the concentrations of two 20S core subunits (C8 and C9) and three 22S ATPases (MSS1, S4 and TBP1) during differentiation. Concentrations of m-calpain and beta-tubulin mRNAs were also assessed. Differentiation was associated with slight increases (ca. 30%) in concentrations of mRNAs encoding the proteasomal 20S core subunits (C8 and C9) and with large increases (approximately 2-fold) in mRNAs encoding the regulatory subunit ATPases. m-calpain mRNA concentration also increased two-fold following mitogen depletion. beta-Tubulin mRNA concentration remained unchanged early in the differentiation process and thereafter declined. Of interest, changes in proteasomal and m-calpain mRNAs occurred within 6-24 h of mitogen depletion (i.e., at least 24-36 h prior to detectable changes in creatine kinase activity). These results indicate that changes in expression of proteasome and calpains subunits occur early in the differentiation process. These changes may be required for the normal course of differentiation to proceed. Differentiation is associated with larger changes in proteasomal ATPase mRNAs than in 20S core particle mRNAs indicating that either turnover rates of the 22S ATPase subunits are more rapid in differentiating cells than of the 20S core particles or that functions of the regulatory subunits become more important during muscle cell differentiation.

Is captopril-induced improvement of insulin sensitivity mediated via endothelin?

Angiotensin-converting enzyme (ACE) inhibitors have been reported to improve insulin sensitivity during either short-term or long-term administration. Recent studies indicate that endothelin-1 (ET-1) has potent glycogenolytic effects in rat hepatocytes and may cause insulin resistance in rat adipocytes. In addition, ET may also have a role in stimulation of the hypothalamic-pituitary-adrenal axis. To test the hypothesis that part of the effect of captopril in enhancing insulin sensitivity may be mediated via ET and/or by glucocorticoids, we measured 24-h urinary excretion of ET and free cortisol before and after short-term treatment with captopril. The 24-h urinary immunoreactive endothelin (IR-ET) excretion decreased significantly (p < 0.05) from 65 +/- 4 ng at baseline to 42 +/- 3 ng after captopril treatment, whereas no significant change in the 24-h urinary free cortisol excretion was observed. Moreover, no significant change in the 24-h urinary IR-ET and free cortisol excretions was noted in the placebo-treated group. We speculate that ACE inhibitors may exert their effect on insulin sensitivity not only by blocking the renin-angiotensin and kinin systems but also by inhibiting production and/or release of ET.

Effect of intraperitoneal administration of zinc on C57/6J mouse liver--a light microscopic study

Intraperitoneal administration of zinc chloride in vivo at 14 micrograms/g body weight (equivalent to 1/2 LD50) over a 3 week period induced an increase in liver weight. The mean weight of the livers in zinc-treated C57/6J mice was 50% higher than that of control animals. Image analysis revealed a concomitant and significant increase in the cross-sectional area and perimeter of the hepatocytes in the zinc-treated group. The mean cross-sectional area of hepatocytes in the zinc-treated mice was 337.2 +/- 4.3 microns2 as compared to 224.6 +/- 2.9 microns2 in the control group (p < 0.05, Mann-Whitney test). The mean perimeter of hepatocytes in zinc-treated mice was 72.4 +/- 0.5 micron as compared to 58.9 +/- 0.4 micron in control animals (p < 0.05). It would appear that subacute administration of zinc may result in increase in liver mass due to hypertrophy of the hepatocytes.

Bone mass and hip axis length in healthy Asian, black, Hispanic, and white American youths

The primary objective of this study was to examine the associations of ethnicity, diet (calcium, protein, energy), and weight-bearing activity with dual-energy X-ray absorptiometry (DXA)-measured bone mass and hip axis length (HAL) in 423 Asians, blacks, Hispanics, and non-Hispanic Caucasians, aged 9-25 years. Bone mass was expressed as bone mineral content (BMC), bone mineral density (BMD), and bone mineral apparent density (BMAD). The data were analyzed using multiple linear regression, after stratifying for gender and pubertal stage and adjusting for height and weight. With few exceptions, Asians and Hispanics had comparable bone mass to whites at all pubertal stages. Greater femoral neck BMAD in black than white females was observed at all pubertal stages. Black males displayed greater BMD and BMAD than white males at all sites in early puberty and at the femoral neck in maturity. Calcium was positively and protein negatively related to BMAD at the femoral neck in early pubertal females. Among males, calcium was negatively associated with whole body BMC and BMD and spine BMD and BMAD in midpuberty. Weight-bearing activity was not associated with bone mass in females; in males, it was positively related only to femoral neck BMC in early puberty. There was an absence of evidence for ethnic differences in HAL among females. In males, we observed shorter HAL in mature Asians and blacks than whites. Neither diet nor activity was associated with HAL.

Neighborhood risk factors for low birthweight in Baltimore: a multilevel analysis

OBJECTIVES

Past research on low birthweight has focused on individual-level risk factors. We sought to assess the contribution of macrolevel social factors by using census tract-level data on social stratification, community empowerment, and environmental stressors.

METHODS

Census tract-level information on social risk was linked to birth certificate records from Baltimore, Md, for the period 1985 through 1989. Individual level factors included maternal education, maternal age, medical assistance health insurance (Medicaid), and trimester of prenatal care initiation. Methods of multilevel modeling using two-stage regression analyses were employed.

RESULTS

Macrolevel factors had both direct associations and interactions with low birthweight. All individual risk factors showed interaction with macrolevel variables; that is, individual-level risk factors for low birthweight behaved differently depending upon the characteristics of the neighborhood of residence. For example, women living in high-risk neighborhoods benefited less from prenatal care than did women living in lower-risk neighborhoods.

CONCLUSIONS

Multilevel modeling is an important tool that allows simultaneous study of macro- and individual-level risk factors. Multilevel analyses should play a larger role in the formulation of public health policies.

Protein tyrosine phosphatase-dependent activation of beta-globin and delta-aminolevulinic acid synthase genes in the camptothecin-induced IW32 erythroleukemia cell differentiation

Camptothecin, an antitumor drug that specifically targets topoisomerase I, induced IW32 erythroleukemia cells to differentiate along the erythroid pathway, as demonstrated by the increased mRNA and protein expression of hemoglobin. Unlike other chemically induced erythroleukemia cell differentiation, no c-myc mRNA down-regulation was observed in the early phases of drug treatment. Among the heme-synthesizing enzyme mRNAs that were analyzed, only that of the erythroid-specific delta-aminolevulinic acid synthase (ALAS-E) was stimulated. Vanadate or benzylphosphonic acid, which inhibited protein tyrosine phosphatases (PTPase), blocked the camptothecin-induced differentiation. Maximal inhibition was attained if vanadate was added within the first 6 hr of camptothecin treatment, after which vanadate gradually lost its effectiveness. Camptothecin-induced expression of beta-globin or ALAS-E transcript levels was inhibited in the presence of cycloheximide or vanadate. It was also shown that vanadate blocked differentiation of IW32 cells induced by sodium butyrate, VM-26, and p53. Increased PTPase activity could be observed 48 hr after cells were treated with camptothecin, VM-26, or sodium butyrate. Analysis of PTPase activity in the course of camptothecin treatment showed elevated levels of PTPase in the cytosol and the nucleus, with a greater increase demonstrated in the cytosol than in the nucleus. Our results suggest that by stimulating the beta-globin and ALAS-E gene expression, PTPase plays a critical role in the induced differentiation of IW32 erythroleukemia cells.

Associations of vitamin C, calcium and protein with bone mass in postmenopausal Mexican American women

We investigated the associations of vitamin C, calcium and protein intakes with bone mass at the femoral neck and lumbar spine in postmenopausal Mexican American women. Bone mass was measured by dual-energy X-ray absorptiometry (DXA) and expressed as areal (BMD, g/cm2) and volumetric (bone mineral apparent density or BMAD, g/cm3) bone mineral density. Diet was assessed using a modified version of the National Cancer Institute Food Questionnaire, which was administered by trained bilingual interviewers familiar with Mexican dietary practices. Data gathered from 125 subjects were analyzed using multiple linear regression analysis with age, body mass index (BMI), acculturation, years of estrogen use, physical activity, total energy intake, and the nutrient of interest as independent variables. Neither calcium nor calcium/protein ratio was associated with bone mineral density. There was evidence of a positive association between dietary vitamin C intake and femoral neck BMD (beta = 0.0002 g/cm2 per mg/day, SE = 0.00006, p < 0.05), but vitamin C was not associated with lumbar spine bone mass. Further investigation of the role of vitamin C in skeletal health is warranted.

[Acute uremic pericarditis presented as cardiac tamponade with acute ischemic hepatitis: a case report]

Pericarditis is a frequent and serious complication of chronic uremia. The uremic pericarditis can get much improvement by aggressive heparin-free hemodialysis therapy. However, the presenting symptoms and signs are too nonspecific to identify at early stage. Cardiac tamponade is the late and fatal complication, and need the immediate & adequate management. A 35-year-old female patient suffered from nausea, vomiting and right upper quadrant dull pain in November 1993, and was admitted to a local hospital. Uremia (BUN: 210 mg/dl, serum Cr.: 13.2 mg/dl) and abnormal liver function (SGOT: 330 IU/L, SGPT: 449 IU/L) were found, then she received regular hemodialysis therapy. About 10 days later, acute exacerbation of liver function (SGOT: 2,488 IU/L, SGPT: 1,048 IU/L), consciousness disturbance and hypotension occurred during hemodialysis. She was referred to our ER immediately. At ER, she had been on comatous, shock state with pulseless electric activity. After resuscitation and serial evaluation, cardiac tamponade was diagnosed. Emergent pericardiocentesis and then bilateral partial pericardiectomy were done about 2 hours later. The pericardial effusion was bloody without evidence of malignancy, bacterial or TB infection. The pathology of pericardium revealed chronic inflammation only. HBsAg, Anti-HCV Ab, and anti-HAV IgM were undetectable. So the etiology of acute hepatitis was diagnosed as ischemic hepatitis. Her general condition and vital sign became stable thereafter. The liver function also improved rapidly. She was discharged one month later and received maintainance hemodialysis therapy and no evidence of recurrence till now.

Differences in bone mineral in young Asian and Caucasian Americans may reflect differences in bone size

Bone mineral content (BMC) and areal bone mineral density (BMD) have been reported to be lower in Asian than in Caucasian adults. To determine if racial differences in bone mass are present in younger subjects and whether they reflect differences in estimated volumetric bone density or in bone size, we compared measurements of bone mineral in healthy young Asian- and Caucasian-American males and females. Bone mineral was measured at the lumbar spine (L2-L4), femoral neck (FN), and whole body (WB) by dual-energy X-ray absorptiometry (DXA) in 99 Asians (49 females, 50 males) and 103 Caucasians (54 females, 49 males) ages 9-26 years. Results were expressed as BMC, BMD, and apparent density (BMAD), an estimate of volumetric bone density that reduces the effect of bone size. Subjects were compared on the basis of chronological age as well as by Tanner stage to correct for potential differences in the timing of puberty. Habitual dietary intake and physical activity were also assessed and correlated with bone mineral. The Asian and Caucasian cohorts differed in body size, diet, and physical activity. Asian females were shorter than the Caucasian females at all stages of puberty and weighed less at pre-/early puberty (p < 0.05). Asian males were older than Caucasians at midpuberty (p < 0.01) and weighed less than the Caucasian males at pubertal maturity (p = 0.001). Asian youths also consumed less calcium and reported less weight-bearing activity. Racial differences were most apparent when comparing BMC data. Asian males had greater spine BMC at midpuberty and lower WB BMC at maturity (p < 0.05). Asian females had lower FN BMC through midpuberty and lower WB BMC in pre-/early puberty (p < 0.05). WB BMD and WB BMC/height values were significantly lower in mature Asian versus Caucasian males. No significant racial differences in BMAD were observed. Multivariate regression analysis indicated that the differences in BMD and BMAD between Asian and Caucasian subjects were largely attributable to differences in weight and pubertal stage, and, at the FN, in weight-bearing activity. Further, the explanatory variables were less strongly associated with BMAD than with BMD. In summary, no significant differences in BMD were found between Asian and Caucasian youths through midpuberty; however, WB BMD and WB BMC/height values were lower in Asian males at sexual maturity. We conclude that observed differences in bone mineral between Asians and Caucasians may be partially attributed to the smaller bone size of Asians.

Ethnic differences in immune responses to hepatitis B vaccine

A national vaccination program against hepatitis B virus (HBV) to immunize every newborn was initiated in Taiwan in 1986. A serologic survey of 1,812 fully vaccinated children residing in four aboriginal villages and four adjacent nonaboriginal Han Chinese rural villages was conducted in 1993. Children in three of the four aboriginal villages had significantly lower titers of antibody against hepatitis B surface antigen (anti-HBs) than did children in the nonaboriginal villages. Evaluation of cold chain operation for vaccine storage and transport suggested that cold chain failure was not responsible for the fact that children residing in the more remote aboriginal villages had lower mean titers of anti-HBs. However, children whose parents were both aborigines had lower anti-HBs mean titer than did children whose parents were both ethnic Han Chinese. Children of mixed parental origins had intermediate mean titer of anti-HBs. Serologic responses to Japanese encephalitis virus and diphtheria vaccines did not show such correlation with ethnic groups, indicating that the determinant for HBV hyporesponsiveness among the aboriginal children is distinct from that of other childhood vaccines. It was therefore concluded that host factors pertaining to ethnic origin might be responsible for the hyporesponsiveness to HBV vaccine in the aboriginal populations. This finding, if substantiated with further prospective studies, might provide possible means for more targeted trials to improve vaccine response and to reduce vaccine failure among these well-defined ethnic groups.

Regulation of topoisomerase II expression during the VM-26 induced differentiation of IW32 murine erythroleukemia cells

The effect of VM-26, a topoisomerase II targeting drug, on IW32 murine erythroleukemia cells was investigated. The VM-26 induced IW32 cells to differentiate at a non-toxic but cytostatic concentration (0.01 microgram/ml). More than 40% of the cells were induced to synthesize hemoglobin, and cells were arrested in G2/M phase of the cell cycle. Levels of beta-globin mRNA also increased significantly. Cells became committed to erythroid maturation after 16 h of continuous drug exposure. Replacement with fresh VM-26 after 48 h of drug treatment further increased the hemoglobin containing cells to greater than 80%. Unlike other drug induced erythroleukemia cell differentiation, c-myc mRNA expression was not affected by VM-26. Inhibition of topoisomerase II activity was observed during the first 12 h of VM-26 treatment; however, elevated enzyme activity was found thereafter. Northern blot analysis showed significant increase in the expression of topoisomerase IIalpha mRNA at 12 and 24 h after VM-26 addition. These findings indicate that VM-26 inhibited the activity of topoisomerase II and promoted the committed differentiation of IW32 cells along the erythroid pathway. In addition, a parallel increase in mRNA and activity levels of topoisomerase II in differentiated cells suggests that regulation of the enzyme expression occurred in the VM-26 induced erythroid maturation.

A semiparametric extension of the Mann-Whitney test for randomly truncated data

In many applications, statistical data are frequently observed subject to a retrospective sampling criterion resulting in pure right-truncated data. In classical testing problems, the Mann-Whitney test is used for testing the equality of two distributions. A semiparametric extension of this test is developed for the case when truncation is present. We consider a model in which the truncation distribution is parameterized, while the lifetime distribution is left as a nonparametric component. The method is seen to be applicable to many patterns of truncation including left truncation, right truncation, and doubly truncated data for which no other nonparametric or semiparametric test is currently available. Applications of the semiparametric method are given. Simulation results indicate that for pure right-truncated data the semiparametric test is more powerful than a recent nonparametric test.

Preparation and use of fibrin glue in surgery

Fibrin glue (FG) is used to control bleeding, to adhere tissues together, and to seal tissue defects. FG is prepared from platelet-rich plasma or by mixing concentrated fibrinogen solutions with thrombin. Concentrated fibrinogen solutions are produced by cryoprecipitation or by chemical precipitation of plasma. The literature on FG preparation is reviewed in order to compare the advantages and disadvantages of the different products reported and to summarize the clinical applications. It is concluded that additional studies are needed to fully evaluate the advantages and disadvantages of fibrinogen concentrated using cryoprecipitation and chemical precipitation and that specific advantages exist for use of both pooled homologous and autologous blood.

Violence by male partners against women during the childbearing year: a contextual analysis

OBJECTIVES

Many contextual analyses that bridge the micro-level-macro-level gap in identifying risk factors for adverse outcomes have not used methods appropriate for multilevel data. The purpose of this paper is to illustrate the application of appropriate multi-level analytic methods and discuss their implications for public health.

METHODS

A previously published individual-level model of physical violence perpetrated by male partners during the childbearing year was reanalyzed to include variables describing the neighborhoods where the women resided. Logistic regression with estimation methods of the generalized estimating equation was used for the contextual analysis. To assess the advantages of the generalized estimating equation over conventional logistic regression, both were used for the two-level model.

RESULTS

The regression coefficients from the contextual model differed from the betas obtained in the individual-level model. Not only were neighborhood-level variables related to the risk of partner-perpetrated violence, but the presence of these macro-level variables in the models modified the relationships of the individual-level variables to the risk of violence.

CONCLUSIONS

Two-level models that include individual- and community-level factors may be beneficial for purposes of explanation in public health research.

Immunity to diphtheria in children three-to-six year of age in four counties of Taiwan

An immunization program against diphtheria has been implemented in Taiwan since 1955, using combined diphtheria, pertussis and tetanus (DPT) vaccine. Diphtheria immunoglobulin (DIG) level was assessed in serum samples obtained from 1138 children, aged 3-6 years from north, south, east and central part of Taiwan by the VERO cell neutralization method. Specimens were collected by simple random sampling of residents from Hsinchu, Taichung, Pingtung and Hwalien counties, including both aborigines and non-aborigines. The former lived in one or two villages in each county, and the latter lived in a single village next to the former. Ninety-five percent (1086/1138) had a DIG titre > or = 0.01 IU/ml. There was no significant difference by sex, or by residential area. Seventy-nine percent (901/1138) of the children had completed the primary immunization schedule (at the age of 2, 4, 6 and 18 months), and the prevalence of DIG titre > or = 0.1 IU/ml considered to be long-term protective was as follows: 74.6% for 3-year group; 74.5% for 4-year group; 67.9% for 5-year group; 84.7% for 6-year group (including 52.2% who had had a booster shot at early primary school). These findings show that the diphtheria vaccination program provides good immunity in childhood.

Preparation of fibrin glue: a study of chemical and physical methods

Concentrated fibrinogen was prepared from whole blood by cryoprecipitation or chemical precipitation and combined with thrombin to make fibrin glue (FG). Surgical applications of FG include control of bleeding, adhesion of tissues, and sealing of tissue defects. The purpose of this study was to compare cryoprecipitation (cryo) of fibrinogen to precipitation using ethanol, ammonium sulfate (AS), and poly(ethylene glycol) (PEG). Our results suggest that AS precipitation is as effective as cryo in yielding fibrin glues with high bond strengths and is more effective than ethanol and PEG precipitation. In addition, the volume of FG per milliliter of plasma is greater after AS precipitation than after a single freeze-thaw cycle. It is concluded that AS is an efficient means for preparing FG from autologous blood.

Percutaneous transluminal atherectomy of the superficial femoral and popliteal arteries: long-term results in 48 patients

PURPOSE

Evaluate retrospectively the long-term primary patency of directional atherectomy (DA) in the femoropopliteal arteries.

MATERIALS AND METHODS

DA was used alone in 59 patients (47%) or in combination with predilatation to allow passage of the device (43%) or after thrombolysis (10%) to treat 127 (93%) excentric atherosclerotic stenoses and nine (7%) occlusions of the femoropopliteal arteries. Forty-eight patients were followed by telephone interview, scheduled outpatient visits, color-flow Doppler evaluation, and angiography for 1-36 months (mean 16.9 months).

RESULTS

Technical success (reduction of the stenosis or occlusion to less than 30% luminal diameter) was achieved in 110 lesions (80.3%) during 48 procedures in 37 patients. Mean luminal diameter was increased 54% with a concomitant increase in mean ankle/brachial indices of 0.33. According to Kaplan-Meier survival curves, patency at 12 and 24 months was 88% and 75%, respectively. When patients who retained patency but developed restenosis were excluded, the probability of patency at 12, 24, and 36 months was 76%, 58%, and 32%, respectively. Major and minor complications occurred in 15 (21.4%) procedures each for a total complication rate of 42.8%.

CONCLUSION

Based on our results, DA is an effective method for percutaneous treatment of atherosclerotic disease involving the femoropopliteal arteries. It has similar patency but a relatively high complication rate compared with PTA.

Collagen fibres with improved strength for the repair of soft tissue injuries

Our laboratory has developed a process for self-assembly of high strength collagen fibres in vitro which exhibit the characteristic D period. These fibres can be cross-linked by severe dehydration (dehydrothermal cross-linking) at elevated temperature and formulated into devices used to repair soft tissues. This study was conducted to evaluate the effects of dehydrothermal cross-linking time and temperature on the tensile mechanical properties of collagen fibres. The results discussed indicate that the tensile strength of reconstituted collagen fibres is optimized by cross-linking for 5 d at 110 degrees C. Tensile strength and modulus values of 91.8 and 896 MPa are reported for fibres cross-linked in this manner. High tensile strength and modulus values are especially important in developing biodegradable materials that promote healing of orthopaedic structures.

Adiposity, dietary and physical activity patterns in ethnic Chinese youths: a cross-country comparison of Singaporean Chinese and Chinese Americans

During the last decade, childhood obesity has been on the increase in Singapore and many newly industrialized Asian countries. We compared the mean body mass index (BMI) and triceps skinfold (TSF) values, as well as the dietary and physical activity patterns of Singaporean Chinese and Chinese American youths. Chinese Americans had a higher mean BMI but a lower mean TSF than Singaporean Chinese. Dietary comparisons suggest that Singaporean Chinese ate fish and grain products more often than Chinese American youths, while Chinese American youths consumed processed meats, dairy products and snack foods more frequently. Mean frequency of consumption of low fat, traditional Chinese foods such as rich porridge was higher among the Singaporean Chinese, while typical 'American' foods including cheese were consumed more often among the Chinese Americans. Certain food items that were more 'neutral' in terms of their cultural identity, such as carbonated drinks, cookies and bread were consumed with the same mean frequencies in both cohorts. In terms of physical activity, Singaporean Chinese youths, on average, spent more time in sedentary activities, less time sitting, and more time in light or moderate activities. The mean time spent on vigorous activities per day was only one hour in both cohorts. Our study suggests differences in body fat distribution and composition, as well as in dietary and activity patterns, between Chinese American and Singaporean Chinese youths. There is a need to develop obesity indicators that are appropriate for the specific populations involved, and to carefully investigate environmental influences on childhood obesity.

A long-term follow-up study of West syndrome

BACKGROUND

Since the syndrome of infantile spasms, hypsarrhythmia and mental retardation was first delineated, there have been many publications about long-term prognosis of the West syndrome. This paper evaluates some of the early factors on which long-term prognosis may depend.

METHODS

Patients with West syndrome were reviewed retrospectively according to the medical records as classification, response to initial medication regimen, prognosis and present neurological status. Seizure control, speech, psychomotor development, mentality, learning ability, behavior and motor handicap were followed over a mean period of 6.1 years.

RESULTS

Thirty patients with complete hospital records were included in this study. Fourteen cases (46.7%) belonged to the symptomatic group, with a mean age of 3.4 months at onset. Four patients (13.3%) were cryptogenic type and a mean age of onset at 9.3 months. There were twelve cases (40%) in the doubtful group, whose mean onset age was 6.4 months. Of the symptomatic group, 92.8% patients had moderate to severe psychomotor retardation as compared to 25% in the cryptogenic group and 67% in the doubtful group; 35.7% of the symptomatic group patients suffered from motor handicap (spastic quadriplegia and hemiplegia as predominated), but only 8.3% of the doubtful group had motor handicap.

CONCLUSIONS

The data collected showed that the following factors seemed to be related to better prognosis: later onset, normal to mild psychomotor delay upon diagnosis, and good seizure control.

Preoperative spinal artery localization and its relationship to postoperative neurologic complications

PURPOSE

To evaluate the risk of spinal cord revascularization and ascertain the relationship between preoperative spinal arteriography and the frequency of postoperative neurologic injury and overall morbidity and mortality in patients who require surgical repair of thoracoabdominal aortic aneurysms.

MATERIALS AND METHODS

Fifty patients scheduled for surgical repair of a thoracoabdominal aortic aneurysm underwent spinal arteriography. All patients were divided into a positive spinal artery group (in which the spinal artery was identified) or negative spinal artery group (in which the spinal artery was not identified) and further divided based on extent of disease.

RESULTS

The complication rate of spinal arteriography was 4.6%; no patient had a permanent neurologic injury. No significant difference existed between the positive and negative spinal artery groups in occurrence of neurologic injury (P = .88) or combined morbidity and mortality (P = 51).

CONCLUSION

Patients who require spinal cord revascularization do not have greater frequency of neurologic injury or overall morbidity and mortality than those without this requirement. Spinal arteriography enables definitive spinal cord revascularization and thereby reduces the risk of neurologic injury.

Cystic fibrosis in two Chinese infants in Taiwan

Cystic fibrosis was diagnosed in two female infants, respectively nine months old (Case 1) and six months old (Case 2). Clinical presentation of these two infants showed frequent episodes of pneumonia, dehydration and poor weight gain, despite fair intake of food since birth. Hyponatremic, hypochloremic metabolic alkalosis had been found during their previous hospitalizations. In Case 1, stool fat was positive with negative trypsin test. Both cases had abnormal findings on chest X-ray films, but the pancreas showed no remarkable cystic changes from sonography. Plastic-bag method of sweat test showed Na/Cl: 155/185 nmol/L in Case 1, Na/Cl: 127/135 nmol/L in Case 2. A family history was suggested, since each one had an elder brother who had died in early infancy with similar clinical presentations. Both patients were put on special diet therapy as well as chest physical therapy. Case 1 died suddenly at 16 months of age. Autopsy revealed mucusplugged dilated ducts with atrophy of the exocrine portion of the pancreas. DNA analysis in Case 2 showed abnormal mutation point at 1898+5 G-->T on chromosome 7.

Nickel chloride inhibits the DNA repair of UV-treated but not methyl methanesulfonate-treated Chinese hamster ovary cells

Nickel, a human carcinogen, has been shown to enhance the cytotoxicity, mutagenicity, and sister-chromatid exchanges (SCE) induced by ultraviolet (UV) light but not by methyl methanesulfonate (MMS). To verify that the cocytotoxicity and cogenotoxicity of nickel are correlated with its inhibition on DNA repair, the effects of nickel on the DNA repair induced by UV and by MMS have been investigated. Our analyses of DNA repair of single-strand breaks by alkaline elution and alkaline sucrose sedimentation indicate that nickel inhibited the DNA repair in UV-treated, but not in MMS-treated cells. Therefore, the inhibition of DNA repair seems to play an important role in the cocytotoxicity and comutagenicity of nickel. However, the inhibition of DNA repair seems not to play a decisive role in enhancing SCE, because we have previously shown that arsenite inhibits the UV-induced DNA repair, but has no enhancing effect on the UV-induced SCE. Our results also show that nickel had obvious inhibitory effects on DNA ligation and postreplication repair, but had no apparent effect on nucleotide excision and DNA polymerization in the UV repair. The results of the DNA ligation inhibition by nickel in UV but not in MMS repair suggest that different ligases are used in the DNA repair of UV- and MMS-induced damages.

Statistical models for prevalent cohort data

In prospective cohort studies individuals are sometimes recruited according to a certain cross-sectional sampling criterion. A prevalent cohort is defined as a group of individuals who have a certain disease at enrollment into the study. Statistical models for the analysis of prevalent cohort data are considered when the onset or diagnosis time of the disease is known. The incident proportional hazards model, where the time scale is duration with disease, is compared to the prevalent proportional hazards model, where the fundamental time scale is follow-up time. In certain cases the time of enrollment may coincide with another event (such as the initiation of treatment). This situation is also considered and its limitations highlighted. To illustrate the methodological ideas discussed in the paper, the analysis of data from an observational study of zidovudine (ZVD) in patients with the acquired immunodeficiency syndrome (AIDS) is presented.

20/20 Analysis: taking a close look at the margins

This article presents "20/20 Analysis" as an experimental, output-oriented, noncategorical alternative to traditional approaches to identification of students for special education. 20/20 Analysis identifies students showing least (below 20th percentile) and most (above 80th percentile) progress toward important objectives of education in a school. The situation of each student in low 20% and high 20% groups is then examined as a basis for broad (noncategorical) approaches to improvement of learning opportunities. Case studies of two schools are present. Policy implications are considered briefly.

Prenatal factors associated with breastfeeding duration: recommendations for prenatal interventions

This study of 198 urban breastfeeding women examined the psychosocial, demographic, and medical factors identified prenatally that may be associated with longer breastfeeding duration and may serve as suitable areas for prenatal breastfeeding promotion interventions. Of 11 psychosocial and demographic factors examined, 5 were important influences on breastfeeding duration: anticipated length of breastfeeding, normative beliefs, maternal confidence, social learning, and behavioral beliefs about breastfeeding. Methods of multivariate linear regression were used to identify prenatal factors that influenced anticipated length. Of the 10 factors entered into the regression model, parity, plans to return to work or school by six months postpartum, and maternal confidence were the most significant factors affecting anticipated length of breastfeeding. Our data suggest several factors amenable to intervention during the prenatal period that appear to influence breastfeeding duration. Prenatal promotion efforts could easily incorporate strategies that influence factors such as normative and behavioral beliefs and maternal confidence.

N-estimation from retrospectively ascertained events with applications to AIDS

It is a common sampling scheme in retrospective studies that the data set includes only individuals who satisfy a certain sampling criterion. In this paper we consider the situation when the sampling criterion is a specified event, and assume that an earlier event can be retrospectively identified given the occurrence of the specified event. A semiparametric method, which is a compromise between nonparametric and parametric methods, is employed for the estimation of the expected number of the specified events (namely, the N-estimation) occurring in arbitrarily given intervals. A number of statistical properties of the estimates are developed. Due to the limitation of semiparametric models, our estimates should be regarded as conservative estimates since in general they underestimate the actual number of the specified events. This type of limitation, however, cannot be avoided with nonparametric or semiparametric models. Applications to acquired immunodeficiency syndrome (AIDS) cases are considered. The blood transfusion AIDS cases reported to the Centers for Disease Control are analyzed in detail.

A review of the etiology and treatment of skin ulcers with wound dressings: comparison of the effects of occlusive and nonocclusive dressings

This article reviews the etiology and treatment of skin ulceration caused by external pressure, vascular insufficiency, and diabetes. In the case of pressure sores, compression of skin against bone may cause ischemic injury to underlying fat and muscle that precedes necrosis of dermis and epidermis. Venous and arterial insufficiency lead to leg ulcers as a result of incompetency of the valves in the veins connecting the superficial to the deep venous systems and atherosclerosis, respectively. Diabetics are susceptible to foot ulcers because of atherosclerosis and the resulting occlusive arterial disease and peripheral neuropathy. Once the underlying medical condition is solved, occlusive and nonocclusive wound dressings can be used in an attempt to promote healing. A review of the literature of animal and clinical studies suggests that both occlusive and nonocclusive wound dressings promote healing compared with air-exposed wounds. Dressings that absorb wound fluid offer some advantages over those that do not absorb large quantities of fluid in heavily exudative wounds and may require less frequent dressing changes. However, the chemistry of the material that comprises the wound dressing seems unimportant unless the material is biologically active. It is likely that the next generation of wound dressings will be composed of a moisture-retaining material coupled with material that has biological activity.

Analysis of allergenic components of Bermuda grass pollen by monoclonal antibodies

A panel of 16 monoclonal antibodies (MoAbs) directed against Bermuda grass (Cynodon dactylon) pollen (BGP) were generated for identification and purification of the major allergenic components of the eliciting antigen (Ag). Radioimmunoprecipitation (RIP) analysis revealed that there were at least eight antigenic components with molecular weights (MW) ranging from 12 kilodalton (12 kDa) to 200 kDa. Each of these components has distinct biochemical characteristics based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and isoelectric focusing (IEF). Among them, Cyn d Bd67K and Cyn d Bd58K were basic proteins, Cyn d Bd35K consisted of at least four isomeric components with isoelectric points ranging from 6.2 to 7.2. The other antigens (Cyn d Bd68K, 48K, 38K, Cyn d Bd200K, Cyn d Bd46K, Cyn d Bd25K and Cyn d Bd12K) were all acidic proteins. The IgE binding capacity of all these antigens was determined with sera from 11 BGP-allergics by using a modified radioallergosorbent test. All but one of the antigens (Cyn d Bd200K) were found to react with human IgE from sera of BGP-allergic patients. Among those human IgE-binding molecules, Cyn d Bd35K reacted with allergic sera most frequently (10 of 11), followed by Cyn d Bd58K (8 of 11) and Cyn d Bd46K (7 of 11) respectively. Our results suggest that Cyn d Bd35K, Cyn d Bd58K, and Cyn d Bd46K are major allergens of BGP, and the MoAbs we obtained should be valuable tools for further purification of these allergens.

Long-term safety and efficacy of zidovudine in patients with advanced human immunodeficiency virus disease. Zidovudine Epidemiology Study Group

An epidemiologic study was initiated in 1987 to evaluate the long-term safety and efficacy of zidovudine in patients with advanced human immunodeficiency virus disease. Data from 886 patients with the acquired immunodeficiency syndrome (AIDS) or AIDS-related complex and CD4+ lymphocyte count less than 0.25 x 10(9)/L are reported. Eighteen-month survival was 67% for the cohort. Pretreatment factors associated with increased survival time included index diagnosis of AIDS-related complex, hematocrit of 0.35 or greater, CD4+ lymphocyte count of 0.15 x 10(9)/L or greater, high functional status, and time from diagnosis of AIDS to treatment of less than 60 days. By proportional hazards analysis, development of serious anemia was the most significant factor associated with early death. Receiving zidovudine for a high proportion of time significantly improved chances of survival even if anemia developed. Serious leukopenia occurring in 37% and serious anemia occurring in 32% of patients. Nonhematologic adverse events were uncommon and no previously unreported adverse events were seen.

Low prevalence of neurological and neuropsychological abnormalities in otherwise healthy HIV-1-infected individuals: results from the multicenter AIDS Cohort Study

Accurate description of the prevalence of neurological impairment in healthy individuals who are infected with human immunodeficiency virus type 1 (HIV-1) has relevance for public health policy, for employment issues, and for planning future health needs. Within the Multicenter AIDS Cohort Study, we determined the cross-sectional prevalence of neurological abnormalities in 270 HIV-1 seropositive homosexual and bisexual men in Centers for Disease Control Groups II and III, using a control group of 193 HIV-1 seronegative homosexual men. Utilizing a neurological and neuropsychological screening battery, we found no differences in the prevalence of neuropsychiatric symptoms or in neuropsychological performance. One hundred nineteen subjects with abnormalities on screening tests completed additional neuropsychological testing and had neurological examinations. The majority had normal results and the frequency of neurological abnormalities and impaired neuropsychological performance was not significantly increased among HIV-1 seropositive subjects. Most of the abnormalities could be attributed to causes other than HIV-1. One subject had mild HIV-1-related dementia, yielding a prevalence of 3.7:1,000 (95% confidence interval: 0.19-23.7:1,000). Magnetic resonance imaging demonstrated sulcal prominence and focal areas of high signal intensity in white matter in 63% of HIV-1 seropositive subjects and 48% of uninfected control subjects. Abnormalities in cerebrospinal fluid were noted in 23 (85%) of 27 HIV-1-infected individuals. Our studies indicate that the prevalence of dementia and other HIV-1-related neurological disorders is very low among healthy HIV-1 seropositive homosexual men. The confounding effects of factors such as substance abuse or preexisting medical conditions must be considered in the neurological evaluation of such patients.

Acquired immunodeficiency syndrome (AIDS)-free time after human immunodeficiency virus type 1 (HIV-1) seroconversion in homosexual men. Multicenter AIDS Cohort Study Group

To estimate the time interval between human immunodeficiency virus type 1 (HIV-1) seroconversion and acquired immunodeficiency syndrome (AIDS) diagnosis in homosexual men, prospective incident cohorts are difficult to obtain and, if assembled, provide few events owing to the long incubation time. Although seroprevalent cohorts are numerous in size and events, the information is limited due to the unknown times since seroconversion. To combine the information provided by 1,628 seroprevalent men (304 AIDS cases) and 233 seroconverters (12 AIDS cases) being followed in a multicenter study since 1984, the postseroconversion changes in hematologic variables occurring in the incident cohort were used to develop a model that allowed for the imputation of the unknown times since seroconversion for the seroprevalent cohort. Nonparametric life table methods incorporating truncation and censoring were applied for the estimation of the probability distribution of the AIDS-free time after seroconversion. The precision of the estimates was evaluated using bootstrap methods. The analysis suggested that AIDS is unlikely (less than 0.5%) in the first year; 78% of seropositive homosexual men remain AIDS-free 60 months after seroconversion; and the AIDS incidence increases for months 12-36 and levels off at 38 per 1,000 person-semesters for months 42-60. The nonparametric estimate of the incidence rate suggests a median AIDS-free time of 11 years, which is longer than previous estimates based on parametric models.

[Using anti-sera and monoclonal antibodies against Aspergillus fumigatus to study its cross-reactions with Alternaria alteria and Penicillium sp]

Using rabbit polyclonal and mouse monoclonal antibodies against Aspergillus fumigatus, we analyzed their cross-reaction with Alternaria alteria and Penicillium sp. by enzyme immuno assay (EIA) and radioimmunoprecipitation (RIP). It was found that neither of these two categories of antibodies reacted with Alternaria alteria while both reacted with Penicillium sp.. When components from Penicillium sp. precipitated by rabbit antisera were analyzed on 10% SDS-polyacrylamide gel electrophoresis (SDS-PAGE), a wide range of bands with molecular weights larger than 90 K and a single 70 K band were observed. No band was found after the rabbit antisera was adsorbed with Aspergillus fumigatus. Moreover, two monoclonal antibodies against Aspergillus fumigatus cross-reacted with high molecular weight (greater than 200K) components of Penicillium sp.. These results suggest that the antigen of Alternaria alteria is different from that of Aspergillus fumigatus, and that Penicillium sp. and Aspergillus fumigatus share some antigenic components. In another experiment, human allergic sera containing IgE antibodies to Aspergillus fumigatus were tested against Penicillium sp. by RIP. No cross-reaction was observed. This suggests that in spite of sharing common antigenic components between these two fungi, the allergenic components of Aspergillus fumigatus is different from those of Penicillium sp..

Monoclonal antibodies specific for human IgE and their clinical applications

By applying the hybridoma technique, two mouse anti-human Immunoglobulin E (IgE) monoclonal antibodies, designated as E17-58 and E20-62, were generated and characterized. E17-58 was a murine IgG2b with an affinity constant of 4 x 10(8)l/mole. E20-62 was a murine IgG1 with an affinity constant of 1 x 10(8) l/mole. These two antibodies recognized different antigenic determinants specific to the IgE molecule. They were used in combination to quantify the total serum IgE level of forty-nine persons. Data obtained correlated highly with that obtained by using the Pharmacia PRIST Kit (r = 0.91). E17-58 was also used to detect the anti-Aspergillus specific IgE of twenty-one atopic patients by a radioimmunosorbent test. The positive rate detected correlated very well with the skin test (p less than 0.05). In addition, in the Western blot system, these monoclonal antibodies were capable of identifying IgE binding components of crude allergen extracts. Extracts from pollens of Bermuda grass were evaluated, and a new major allergenic component with a molecular weight of 40 kd was identified.

The effect of zinc deficiency and food restriction on prostaglandin E2 and thromboxane B2 in saliva and plasma of rats

Zinc has been implicated in the regulation of prostaglandins and other arachidonic acid derivatives. Studies of zinc-deficient animals, however, are compromised by concomitant reduction in food intake that may also alter eicosanoid levels in body tissues and fluids. In this study, three groups of rats, designated as zinc-deficient, pair-fed and control, were fed diets containing 1 ppm, 15 ppm (in amounts paired to deficient rats) and 15 ppm Zn ad libitum, respectively, for 6 weeks. Saliva and blood were analyzed for PGE2 and TXB2 by radioimmunoassay. Saliva concentrations of both eicosanoids were lower (p less than 0.05) in the pair-fed animals, but not significantly altered by zinc deficiency. Plasma levels of PGE2 and TXB2 were unchanged by either zinc deficiency or food restriction. The results of this study support the contention that the effect of zinc on these prostaglandins is not mediated by altered rates of synthesis or degradation but rather by effects on eicosanoid function.

Relative reliability of five serially measured markers for prognosis of progression in prostate cancer

During an 8-year period, 1,065 serum specimens were collected from 79 patients with prostate cancer of stages B2 to D1 (group I) and 51 patients with newly diagnosed stage D2 prostate cancer (group II) to evaluate statistically the relative reliability of elevated tumor-associated markers for progressive disease in prostate cancer. Forty of the group I patients and 21 of the group II patients presented a clinical progression of disease during follow-up. With the use of Gail's modification of Cox's regression model, serial acid phosphatase (AcP), total alkaline phosphatase (TAP), bone alkaline phosphatase (BAP), prostatic acid phosphatase (PAP), and prostate-specific antigen (PA) were analyzed. Results from group I patients revealed that only PA (P = .0002) and PAP (P = .0684) were prognostically important markers for detection of imminent disease progression. However, all markers were prognostically important in group II patients. Comparative studies indicated that PA (P = .0052) and PAP (P = .0359) were the more reliable markers for group I patients, whereas PA (P less than .0001), BAP (P = .0007), and PAP (P = .0206) were the more reliable markers for group II patients. Multivariate analyses revealed that, after adjustment for the effect of PA, no other marker was significantly related to the risk of progression. Elevated PA levels were predictive of increased risk 6 months before disease progression in group I patients only (P less than .0001). Overall, the apparent order of prognostic reliability for disease progression was found to be PA greater than PAP greater than BAP greater than AcP greater than TAP.