Effect of topographical aspect and farm system on the population dynamics of Trichostrongylus larvae on a hill pasture

The population dynamics of Trichostrongylus colubriformis larvae were compared over two years on contrasting topographical aspects north (warm and dry) and south-facing (cool and moist) hill slopes) on paddocks which form part of the 'non-chemical' and conventional' farm systems at the AgResearch Ballantrae Hill Country Station located in a summer-moist region of New Zealand. Sheep faeces containing 50,000 Trichostrongylus eggs were incubated for 4 days at 25 degrees C and then deposited on each of 36 sub-plots in each of 8 plots in a 2 x 2 factorial design in the summer (summer trial) and again in autumn (autumn trial). Pasture was removed to ground level and larvae extracted from six sub-plots from each plot 2, 4, 6, 8, 11 and 14 weeks after contamination in all trials. Larvae were recovered from two strata, 0-5 cm above the soil surface and > 5 cm above the soil surface. Fewer (p < 0.001) larvae were recovered from herbage (47 vs. 118) and residual faeces (28 vs. 246) from the autumn than from the summer trials. This coincided with more rapid (p < 0.001) faecal disappearance in the autumn trials. In the summer trials, fewer (p < 0.003) larvae were recovered from the herbage (101 vs. 182) and residual faeces (140 vs. 352) from plots on the south than the north facing aspect. In the autumn trials there was a rapid (p < 0.0001) faecal disappearance from the south-facing aspect. In the autumn trials there was a non-significant (p < 0.10) trend for fewer larvae to be recovered from the south-facing aspect (2 vs. 54). This also coincided with more rapid faecal disappearance from the south-facing aspect. There was no effect of farm system on the number of larvae recovered. Despite greater (p < 0.0001) numbers of larvae recovered from the bottom stratum of herbage, the density of larvae (L3/kg DM) tended (p < 0.12) to be higher in the top stratum of herbage. It was concluded that season and aspect have a marked effect on the number of larvae recovered from herbage and that this was inversely related to the rate of faecal disappearance.

Analysis of Australian Crohn's disease pedigrees refines the localization for susceptibility to inflammatory bowel disease on chromosome 16

A number of localizations for the putative susceptibility gene(s) have been identified for both Crohn's disease and ulcerative colitis. In a genome wide scan, Hugot et al. (1996) identified a region on chromosome 16 which appeared to be responsible for the inheritance of inflammatory bowel disease in a small proportion of families. Subsequent work has suggested that this localization is important for susceptibility to Crohn's disease rather than ulcerative colitis (Ohmen et al. 1996; Parkes et al. 1996). We investigated the contribution of this localization to the inheritance of inflammatory bowel disease in 54 multiplex Australian families, and confirmed its importance in a significant proportion of Crohn's disease families; we further refined the localization to a region near to D16S409, obtaining a maximum LOD score of 6.3 between D16S409 and D16S753.

Gastrointestinal adenocarcinomas metastatic to the testes and associated structures in three dogs

Primary testicular neoplasms are common in dogs, but metastases to the testes are rare. Three dogs had enlargement of the testes and associated structures. Upon histological examination, the enlargements were due to metastatic adenocarcinomas. Further examination identified the gastrointestinal tract as the primary site of the metastatic neoplasms in all three cases. The testicular metastases reflected widespread metastatic disease. When metastatic adenocarcinoma is found in the testes and associated structures in dogs, the gastrointestinal tract should be examined closely for a primary tumor site.

Polymorphism of the Pi class glutathione S-transferase in normal populations and cancer patients

Deficiencies of the glutathione transferase isoenzymes GSTM1-1 and GSTT1-1 have been shown to be risk modifiers in a number of different cancers but there have been no similar studies with GSTP1-1, the only member of the Pi class of glutathione S-transferases expressed in humans. Over-expression of GSTP1-1 in tumours suggests that it may be a significant factor in acquired resistance to certain anticancer drugs. We previously identified a cDNA clone with two amino acid substitutions (I105V, A114V). This clone suggests that the GSTP1 gene is polymorphic and it is possible that the different genotypes may be associated with altered cancer risk or drug resistance. In the present study, we report methods for genotyping individuals at codons 105 and 114 of GSTP1 and demonstrate that these two loci are polymorphic in several different racial groups. We also detected significant linkage disequilibrium between these two loci. To determine if either of the alleles at these two loci were associated with altered cancer susceptibility, we genotyped individuals with colorectal cancer or lung cancer. A total of 131 colorectal and 184 lung cancer patients were compared with 199 control individuals. Overall, there were no significant associations between the GSTP1 polymorphisms and either form of cancer.

The Fresno Asthma Project: a model intervention to control asthma in multiethnic, low-income, inner-city communities

The Fresno Asthma Project targeted the entire low-income, inner-city, multiethnic population of Fresno, California. For 36 months following a 6-month planning phase, continuing education was provided to a high proportion of physicians, pharmacists, nurses/respiratory therapists, emergency medical technicians, school personnel, and allied health professionals involved in asthma care in Fresno, including virtually all those providing care/services to the target population. Small group patient education was made available and provided in age- and culturally appropriate formats to patients/families in clinics, hospitals, and schools. General and ethnic media and a Speakers Bureau were used to raise public awareness of asthma as a serious but controllable health problem. This community intervention model is particularly appropriate to multiethnic communities. It is relatively low cost (total direct costs were $140,000 per year), uses existing educational resources, and appears to have minimized counterproductive competition. Although morbidity and mortality trend data are not yet available to monitor program impact, penetration into the target community has been substantial: community physicians refer patients to asthma classes, asthma educator training is ongoing through the local American Lung Association chapter, hospitals and managed care systems serving low- income/MediCal patients offer asthma classes, and public schools and HeadStart are institutionalizing asthma awareness and self-management classes.

Uterine arteriovenous malformations: gray-scale and Doppler US features with MR imaging correlation

PURPOSE

To describe the gray-scale and color and duplex Doppler ultrasound (US) and the magnetic resonance (MR) imaging features of uterine arteriovenous malformations (AVMs).

MATERIALS AND METHODS

Uterine AVMs in 10 patients were retrospectively evaluated. All patients underwent gray-scale US and color and duplex Doppler US. Nine underwent angiography with therapeutic embolization; four, MR imaging. The resistance index (RI), pulsatility index (PI), and peak systolic velocities (PSVs) were evaluated.

RESULTS

At gray-scale US, uterine AVMs were nonspecific and manifested as subtle myometrial inhomogeneity, tubular spaces within the myometrium, intramural uterine mass, endometrial mass, or cervical mass or sometimes as prominent parametrial vessels. Color Doppler features were consistent and included intense juxtaposed signals with aliasing and apparent flow reversals. Spectral Doppler US revealed low-resistance flow (RI, 0.25-0.55; PI, 0.3-0.6) and PSVs greater than 96 cm/sec, which suggests arteriovenous shunting. MR imaging showed a bulky uterus, a focal uterine mass, disruption of the junctional zones, serpiginous flow-related signal voids, and prominent parametrial vessels.

CONCLUSION

Gray-scale morphology and Doppler US features should allow noninvasive diagnosis of uterine AVMs. Doppler and MR imaging features of uterine AVMs may overlap with other causes of arteriovenous shunting, including abnormal placentation and gestational trophoblastic disease (GTD). These can be differentiated with serum beta human chorionic gonadotropin test results (negative with AVM, positive with GTD).

Individual versus group education: is one better?

Individual and small group approaches to delivering patient education have differing potential advantages, and various criteria can be used to determine which is "better". Individualization of education is possible in either delivery format, as is its absence. Limited evidence regarding the relative effectiveness and cost-effectiveness of different delivery modes is available from direct comparison and meta-analyses of studies comparing either of the approaches with no education or the patient's own pre-education status. This evidence supports the conclusions that: (1) both individual and group education can improve patient outcomes, (2) it is not possible to conclude that the two delivery formats are essentially equivalent in effectiveness, and there is some evidence that group education may more effective for some outcomes, and (3) wide variation in effectiveness exists among programs in both delivery formats. A model continuum of asthma education is presented that takes advantage of the respective strengths of individual and group delivery.

Respiratory effects associated with indoor nitrogen dioxide exposure in children

BACKGROUND

The human health effects of exposure to indoor nitrogen dioxide (NO2) are unclear, and few studies have examined the effects of short-term peak levels of exposure.

METHODS

The association between indoor exposure to NO2 and respiratory illness was examined in 388 children aged 6-11 years. The NO2 levels were monitored during winter in 41 classrooms, from four schools with unflued gas heating and four schools with electric heating. Each classroom was monitored daily with 6-hour passive diffusion badge monitors over nine alternate weeks, and with hourly monitors over two of those weeks. Children living in homes with unflued gas appliances were also monitored daily over four evenings during times of gas use.

RESULTS

Exposure to NO2 at hourly peak levels of the order of > or = 80 ppb, compared with background levels of 20 ppb, was associated with a significant increase in sore throat, colds and absences from school. An increase in cough with phlegm was marginally significant. Significant dose-response relationships were demonstrated for these four measures with increasing levels of NO2 exposure.

CONCLUSIONS

Short-term peak levels of exposure are important to consider in relation to adverse respiratory effects associated with NO2 exposure.

Introduction of an ultrasound picture archiving and communication system: experience in the first year

OBJECTIVE

To describe the authors' first year's experience with a picture archiving and communication system (PACS) for the management and storage of ultrasound images and to discuss the financial impact of the system in terms of costs of purchase, installation and operation.

MATERIALS AND METHODS

The Toronto Hospital, General Division, performs more than 30000 ultrasound studies each year. On June 27, 1994, an Ultra PACS (ALI Technology Incorporated, Richmond, BC) was introduced as the only method of image storage and archiving in the Ultrasound Division.

RESULTS

After structural renovations and a detailed work flow analysis, the Ultrasound Division converted from film to the PACS over a single weekend with no back-up. The advantages to date include consistently high-quality images; rapid image retrieval (images from the same day [online], 0 to 45 seconds; archived images [online], 3 to 5 minutes; images in storage [offline], 3 minutes); no loss of images; more efficient patient through-put, which allows the division to handle the same number of patients in 20% less operational time (change from a 10-hour day to an 8-hour day, over a 5-day week); less end-of-day overtime; and an improved work environment. There has been no change in the division's complement of full-time equivalent technologists, the number of film librarians has been reduced by 1, and physician service time has decreased by 20%. There has been no significant impact on overall operational financial status.

CONCLUSION

The PACS has proved an efficient method for managing large numbers of ultrasound images in a cost-effective and technically sound manner. Its installation provides the basis for meeting the Ultrasound Division's next objective, to eliminate paper as the primary method of managing patient information and reports.

The partition matrix: exploring variable phylogenetic signals along nucleotide sequence alignments

The partition matrix is a graphical tool for comparative analysis of nucleotide sequences following alignment. It is particularly useful for investigating the divergent phylogenies of sequence regions undergoing reticulate evolution. A partition matrix is generated by determining the consistency of the parsimoniously informative sites in a set of aligned sequences with the binary partitions inferred from the sequences. Since the linear order of sites is maintained, the matrix can be used to assess whether the distribution of sites either supporting or conflicting with particular partitions changes along the length of the alignment. The usefulness of the matrix in allowing visual identification of differences in evolutionary history among regions depends on the order in which partitions are shown; several suitable ordering schemes are proposed. We demonstrate the use of the partition matrix in interpreting the evolution of the pseudoautosomal boundary region on the sex chromosome of catarrhine primates. Its routine use should help to avoid attempts to derive single phylogenies from sequences whose evolution has been reticulate and to identify the gene conversion or recombination events underlying the reticulation. The method is relatively fast. It is exploratory, and it can form the basis for more formal analysis, which we discuss.

On extending the transmission/disequilibrium test (TDT)

The transmission/disequilibrium test (TDT), for evaluation of the null hypothesis of neither linkage nor association between a marker locus and disease, is extended to the more general situation of transmission of two multi-allele marker loci from parents to affected offspring. Transmission probabilities are derived for a generalized single locus disease model, where the disease locus is taken to lie between the two marker loci. There could be unlinked modifier loci for the disease. Examples of the extended TDT are given and it is shown how the contribution from each locus can be evaluated, both separately and jointly.

Bridging language and cultural barriers between physicians and patients

OBJECTIVE

This study explored a group of primary care physicians' use of various methods to bridge language and cultural barriers between themselves and their patients and the physicians' perceptions of the availability and quality of these methods.

METHODS

The authors mailed a questionnaire to 495 primary care physicians in the Greater Bay Area of northern California, an area chosen for its ethnically diverse population. Respondents were asked to estimate how many patients they saw per week, how many encounters they had per week with non-English-speaking patients, and how often they used each of six interpretation methods. They were also asked to assess the availability and quality of interpretation services.

RESULTS

Physicians reported that, on average, 21% of visits were with non-English-speaking patients. Trained medical interpreters or the AT&T Language Line were used, on average, in fewer than 6% of these encounters, and no interpreters were used in 11%. In 27% of encounters with non-English-speaking patients, the physician could speak the patient's language, in 20% interpretation was done by a staff member who had no formal interpretation training, and in 36% a family member or companion of the patient interpreted. Physicians who had access to trained interpreters reported a significantly higher quality of patient-physician communication than physicians who used other methods (P < 0.0001).

CONCLUSIONS

In an area of great ethnic diversity where physicians who had access to the services of trained interpreters reported a significantly higher quality of patient-physician communication, the low rates of use of trained interpreters suggest that factors other than quality, such as costs, preclude greater use of these services.

Abdominal sonography in asymptomatic executives: prevalence of pathologic findings, potential benefits, and problems

Abdominal ultrasonography was performed on 1000 asymptomatic executives over a period of 6 months as part of a comprehensive health examination. The use of ultrasonography in these persons was evaluated with regard to the prevalence and variety of pathologic conditions detected as well as potential benefits, risks, and use as a screening tool. Significant sonographic diagnoses included renal cell carcinoma in four patients (0.4%) and abdominal aortic aneurysm in four patients (0.4%). Abdominal sonography performed on 7925 asymptomatic executives over a subsequent 2 1/2 year period led to detection of 23 (0.3%) additional renal cell carcinomas. The prevalence of renal cell carcinoma in this population is substantially greater than that of the general population. Abdominal sonography facilitates detection of occult renal neoplasms and aortic aneurysms. The cost effectiveness and potential use of sonography as a screening tool remains to be determined, however, given the relatively low overall prevalence of these pathologic conditions.

Intraoperative end-tidal carbon dioxide levels and derived calculations correlated with outcome in trauma patients

BACKGROUND

To determine the relationship between the prognosis of seriously injured patients requiring emergency surgery and intraoperative end-tidal CO2 variables and "excess Pco2."

METHOD

Retrospective chart review of 100 seriously injured patients admitted to Detroit Receiving Hospital and requiring major surgery (mortality rate of 40%). Standard intraoperative monitoring, including continuous capnography, plus arterial blood analyses every 15 to 30 minutes during surgery.

RESULTS

After resuscitation for 45 to 90 minutes, 11 patients had a systolic blood pressure < 100 mm Hg and, of these patients, 10 (91%) died. Of the remaining 89 patients, mortality rates were 53% (16/30), with an end-tidal CO2 of 22 mm Hg or less, versus 24% (14/59) with an end-tidal CO2 of 23 mm Hg or more (p = 0.011). An arterial to end-tidal Pco2 difference of 13 mm Hg or more after resuscitation was associated with an increased mortality rate (50% (20/34 vs. 18% (20/55)) (p < 0.005). The mortality rate was particularly high, with a final arterial to end-tidal Pco2 difference of 12 mm Hg or more (73% (30/41) versus 17% (10/59) (p < 0.001). A final Paco2 excess (i.e., the amount by which the Paco2 was higher than expected from the bicarbonate) > 1.0 mm Hg was also associated with an increased mortality rate ((62% (33/53) vs. 15% (7/47)) (p < 0.001).

CONCLUSION

Values derived from the end-tidal CO2 and the excess Pco2 should be monitored intraoperatively in critically injured patients. Efforts should be made to improve cardiac output and adjust ventilation to maintain an end-tidal Pco2 of 25 mm Hg or more, an arterial to end-tidal CO2 difference of 12 mm Hg or less, and an excess Paco2 of 1.0 mm Hg or less.

Patients' perceptions compared with objective ratings of asthma severity

BACKGROUND

Optimal asthma management requires accurate assessment of asthma severity.

OBJECTIVE

To compare patients' perceptions of their asthma severity with that obtained by using the guidelines published by the National Asthma Education and Prevention Program's Expert Panel and with functional impairment measured by spirometry and numeric criteria of the American Thoracic Society.

METHODS

We enrolled 323 patients age 18 to 50 years who were members of the Kaiser Foundation Health Plan for > or = 1 year in a randomized control trial of an asthma education program. Each had a confirmed diagnosis of bronchial asthma and had been receiving antiasthma medication for > or = 1 year. Patients rated the severity of their asthma. Office spirometry was performed, and, using the Mini-Wright peak flow meter, patients kept 2-week diaries of at-home recordings of morning and evening peak expiratory flow rates.

RESULTS

A statistically significant association was noted between patients' perceptions of asthma severity and both medication severity rating (P < .001) and diurnal variation rating (P = .003) and evening peak expiratory flow rate percentage (P = .019). In comparison with a severity composite based on criteria of the National Asthma Education Program, 54% of patients accurately estimated asthma severity, 27% overestimated, and 20% underestimated severity.

CONCLUSION

A clinically significant proportion of asthmatic patients substantially underestimate disease severity and thereby may be at risk of increased mortality or morbidity.

Biological applications of fullerenes

Thus far, development of applications of fullerenes in biology has been hampered by the poor water solubility of fullerenes. In spite of such concerns, fullerenes have proved useful for a wide variety of biological applications. As derivatized and underivatized fullerenes continue to become increasingly available, additional applications and further development of those discussed in this article will invariably follow.

Manifestations of Crohn disease at US

Crohn disease is a chronic inflammatory disorder of the intestines that is characterized by multiple episodes of exacerbation and remission. Although barium studies and endoscopy remain the most valuable tools for assessment of mucosal and luminal changes, sonography has proved to be a safe and noninvasive modality for characterization of mural and perienteric changes. Ultrasonography (US) can accurately demonstrate the classic features of Crohn disease as well as the complications frequently associated with the disease. The addition of color Doppler imaging may allow differentiation of chronic from active bowel wall thickening. In expert hands, US appears to be a sensitive modality for preliminary investigation of patients with symptomatic Crohn disease. US can also be used to assess the response to treatment and to detect postoperative recurrence. Finally, US enables accurate selection of patients in whom the possibility of surgery or percutaneous intervention would justify other means of investigation, particularly computed tomography.

Lipiodol accumulation in hepatic hemangioma. Detection with osmium postfixation

Lipiodol has been used to increase the detectability of small primary neoplasms in the liver. We report a patient who was found to have lipiodol deposits in the liver one month after intra-arterial injection. The region was resected, under ultrasound control, because of the impression that the lesion was malignant. The specimen contained two small hemangiomas as well as many small dysplastic nodules (adenomatous hyperplasia) in a noncirrhotic parenchyma. To locate the lipiodol deposit in this case, the tissue was radiographed, postfixed in osmium tetroxide, and embedded in paraffin. Black osmium-stained deposits were found within the cavities of the hemangiomas but not in the dysplastic nodules. Most of the deposits were extracellular multivesiculated bodies with a small focus of lipid droplets engulfed by multinucleated foreign-body type giant cells. This report reinforces that hepatic lipiodol retention is not specific for hepatocellular carcinoma. We present, for the first time, the histologic appearance of lipiodol accumulation in an hemangioma. The value of osmium tetroxide postfixation for the detection of lipiodol is also demonstrated.

An education program for parents of children with asthma: differences in attendance between smoking and nonsmoking parents

We studied smoking status in relation to parental attendance at an asthma education program for child patients of a health maintenance organization. Nonattendance rates were 24%, 42%, and 78% in nonsmoking, one-smoker, and two-or-more-smoker families, respectively, and 33% overall. Only the number of smokers (odds ratio [OR] = 3.1; 95% confidence interval [CI] = 1.8, 5.3) and perceived adverse impact of asthma on the family (OR = 0.4; 95% CI = 0.2, 0.9) were retained in a multivariate model that correctly classified 73% of families; demographic characteristics, frequency of asthma symptoms, and health care use were rejected. There was a tendency for smoking parents to deny that their child had asthma (17% among families with two or more smokers; 9% among nonsmoking families). Asthma education programs may fail to involve parents who smoke.

Education of parents of infants and very young children with asthma: a developmental evaluation of the Wee Wheezers program

A randomized control trial of the Wee Wheezers asthma education program was conducted with 76 children < 7 years of age, 31% of whom were on a medication regimen consistent with mild, 51% with moderate, and 18% with moderately severe/severe asthma. Treatment children showed improved morbidity at 3-month follow-up relative to the changes in the controls: increased symptom-free days in the preceding 2 weeks (mean change of +2.2 vs. -2.6 in the controls; p = .004) and month (+2.0 vs. -3.8; p < .02), fewer nights of parental sleep interruption in a typical week (+0.7 vs. +1.8; p < or = .05), and a trend toward fewer asthma sick days (-0.2 vs +0.7; p = ns). These improvements were accompanied by significantly better parental asthma management compared with controls (more consistent use of preventive medications, p < or = .01; early symptom intervention, [corrected] p < or = .05) and trends toward more restrictions on smoking in the home (p < .07) and decreased parental confusion about asthma treatment (p < .11). This study provides evidence that a multisession program of asthma education for parents can improve parental asthma management and clinical outcomes in very young children and provides information on the validity and sensitivity of various asthma outcome measures in this age group.

In situ calibration technique for UV spectral radiometers

A technique for calibrating spectral radiometers measuring global (2π sr) irradiance using solar irradiance at the top of the atmosphere as the absolute irradiance reference is reported. In addition to providing a calibration at all measured wavelengths, the technique provides a direct measure of the angular response of the radiometer. For instruments that can be used to measure the ultraviolet-B region, the calibration also provides an estimate of the ozone column amount.

Cytochrome P-450scc-mediated oxidation of (20S)-22-thiacholesterol: characterization of mechanism-based inhibition

(20S)-22-thiacholesterol (1) is found to be a potent competitive inhibitor of pregnenolone biosynthesis from cholesterol by purified reconstituted bovine adrenal cytochrome P-450scc. The apparent dissociation constant Kd, determined from difference spectra, is 0.6 microM, close to the value from kinetic studies for the apparent inhibition constant, Ki, of 0.8 microM. Studies of the time course of pregnenolone production indicate that under turnover conditions the competitive inhibitor (1) is converted to a tighter binding inhibitor, shown to be (20S,22R)-22-thiacholesterol S-oxide (4), with high diastereoselectivity and in a time-dependent manner. Both the diastereomeric sulfoxides, (20S,22S)-22-thiacholesterol S-oxide (3) and (20S,22R)-22-thiacholesterol S-oxide (4), exhibit properties consistent with their being competitive versus cholesterol, but the (22R)-sulfoxide (4) binds approximately 10 times more tightly than the (22S) diastereomer (3). The apparent Kd values of sulfoxides 4 and 3 are 0.1 and 1.14 microM, respectively. EPR and absorption spectroscopic studies of enzyme-inhibitor complexes suggest direct coordination of the oxygen atom of the (22R)-sulfoxide (4) with the catalytic heme center. This implies that the inhibitor operates by directly blocking further reaction at the active site heme group, with a substantial lifetime of the enzyme-inhibitor complex.

Crystal structure of doisynolic acid and the structure of other products formed during its synthesis

The crystal structure of the D-seco-estrogen doisynolic acid shows it to have the natural S configuration at the position derived from C-14 in estrone. Two major by-products during the synthesis of doisynolic acid from estrone are shown to be dimeric steroids. One is an aldol condensation product, and the other appears to arise from an alkaline cleavage of the aldol product.

Prospective study of hospitalization for asthma. A preliminary risk factor model

We conducted an exploratory analysis of several prospectively obtained objective measures of disease activity to derive a predictive model of hospitalization for asthma among 310 adults, ages 18 to 50 yr, with moderate to severe asthma. Baseline characteristics associated with increased risk of hospitalization in the succeeding year include (1) prior year hospitalization, (2) moderate or severe respiratory impairment, (3) a medication regimen consistent with severe asthma, (4) a history of significant systemic steroid use, (5) maximum overnight PEF variability > 40%, and (6) mean evening PEF < 60% of predicted (relative risk = 6.5, 6.9, 8.1, 3.7, 3.0, and 3.2, respectively). Recursive partitioning analysis, depicted as a "classification tree," provided a more sensitive (94%) and specific (68%) multivariate description of the data set than either logistic regression (87 and 48%, respectively) or a simple additive risk model (46 and 93%, respectively). Patients with very high (> 50%), moderately elevated (10 to 15%), and very low (< 5%) risk of hospitalization were identified on the basis of particular combinations of prior hospitalization history, level of respiratory impairment, and medication regimen. Overnight variability and mean evening PEF measured at home over a 2-wk period proved less informative for risk stratification than respiratory impairment determined once at baseline by office spirometry. The findings warrant replication and extension in other populations with the goal of developing decision rules for risk stratification and effective interventions for risk reduction.

Estimates for different stages of HIV/AIDS disease

Software for estimating current and future numbers in different stages of the natural history of HIV infection has been developed. This is based on a general multistage model for the natural history of HIV/AIDS disease, allowing for treatment effects. The multistage model has been incorporated into the general back-projection procedure. For illustration, Australian AIDS data are used here.

Ultrasonography in obstetric and gynecologic emergencies

In conclusion, both transabdominal and transvaginal sonography are valuable tools in the evaluation of the patient who presents with a gynecologic or obstetric emergency and can very quickly lead to a definitive diagnosis or limited differential. Sonography also can be useful in excluding the presence of other pathologies that may mimic obstetric or gynecologic disease including appendicitis, diverticulitis, and renal obstruction.

An X-ray crystallographic study of the nonsteroidal contraceptive agent centchroman

We have determined an X-ray crystal structure for the N-methyl iodide derivative of the nonsteroidal contraceptive centchroman. The pendant aromatic substituents on C-3 and C-4 of the chroman system are nearly perpendicular to the plane of the chroman system, an orientation expected in such a chroman, but perturbed to some degree by the gem dimethyl substituents at C-2. Structural superposition with other nonsteroidal antiestrogens, tamoxifen and nafoxidine, shows a similar disposition of the tertiary amine side chains responsible for antagonist activity. The aryl rings also show good superposition, but in contrast to tamoxifen and nafoxidine, which have the potential for ring double bond conjugation, the centchroman aryl rings show a larger dihedral twist. While different superpositions between the enantiomers of centchroman and the bioactive enantiomer of estradiol (d-estradiol, 8 beta,9 alpha,13 beta,14 alpha,17 beta) are possible, when the chroman ring system is positioned over the AB rings of estradiol, then (3R,4R)-centchroman makes the best fit. The aryl substituents in both enantiomers make comparable overlays with the steroidal skeleton, but the axial methyl group at C-2 in (3R,4R)-centchroman is directed downward along the C-7 alpha axis of estradiol, a site where many substituents are known to be well tolerated by the estrogen receptor, while in the 3S,4S-enantiomer, this methyl group is projected upward. Thus, we suggest that the bioactive l-enantiomer of centchroman will have the 3R,4R absolute configuration.

Opsonic antibodies to Staphylococcus epidermidis: in vitro and in vivo studies using human intravenous immune globulin

Staphylococcus epidermidis is a major cause of nosocomial infections, including sepsis in premature infants. Intravenous immune globulin (IVIG) has been used to prevent neonatal sepsis, but efficacy has varied in different clinical trials. The role of IgG antibody in immunity to S. epidermidis was studied using an opsonophagocytic assay and a lipid-emulsion-induced lethal model of neonatal S. epidermidis sepsis. Opsonic antibody to S. epidermidis varied between IVIG preparations and between lots: Lots with > or = 90% opsonic activity promoted bacterial clearance from blood and significantly enhanced survival when compared with lots with < or = 50% opsonic activity. Absorption of IVIG with S. epidermidis removed in vitro opsonic and in vivo protective activity. These studies suggest that opsonic antibody may play an important role in S. epidermidis immunity in immunocompromised patients, such as premature infants. Standard IVIG, however, may not provide therapy effective in preventing S. epidermidis infections, as many IVIG lots contain insufficient levels of opsonic S. epidermidis antibody.

Effectiveness of educational strategies preparing physician assistants, nurse practitioners, and certified nurse-midwives for underserved areas

A study of physician assistant, nurse practitioner, and certified nurse midwifery programs was undertaken to identify and assess the effectiveness of recruitment, educational, and deployment strategies that programs use to prepare practitioners for medically underserved areas. The 51 programs studied were those having mission statements or known track records relating to this goal. A total of 170 interviews were conducted with faculty, students, graduates, and employers from 9 programs visited on-site and 42 programs surveyed by telephone. All programs had some recruitment and training activities in underserved sites. Only about half of the programs were able to submit data on their graduates' practice settings and specialties. These data suggest that older students who have backgrounds in underserved areas and clearly identified practice goals are more likely to practice in underserved areas. Programs that actively promote service to the underserved do so through publicly stated missions and recruitment and educational strategies that complement these missions. Such programs also are more likely to evaluate and document their success than programs that lack strategies.

Molecular structures, conformational analysis, and preferential modes of binding of 3-aroyl-2-arylbenzo[b]thiophene estrogen receptor ligands: LY117018 and aryl azide photoaffinity labeling analogs

Structural and computational modeling studies were performed on the antiestrogen LY117018 (3) and two photoaffinity labeling analogs, in which an azide replaces the basic ether side chain (methyl ether tetrafluoro azide 7 and its protio analog 8). These studies were undertaken in order to determine the conformational preferences of these compounds and to propose favorable orientational modes for their binding to the estrogen receptor. In the crystallographic studies, we found that, unlike tetrafluoro azide 7, which adopts a face-to-face stacking of the p-hydroxyphenyl and benzoyl groups in the solid state, the pendant rings in the corresponding protio analog 8 are found in a predominantly offset pi-stacked array. In LY117018, which has an ether on the benzoyl ring, stacking of the pendant rings does not occur in the crystal structure; it assumes a T-shape, with the benzoyl group oriented perpendicular to the benzo[b]thiophene nucleus. In modeling studies, analogs of LY117018, 7, and 8 were subjected to a conformational grid search by molecular mechanics, and for each compound, three low-energy conformers (and their atropisomers) were obtained. These conformers were further geometry optimized by semiempirical molecular orbital calculations. For each compound, one of the three minimum-energy conformers is quite similar to the solid-state geometry. The computational structure of the tetrafluoro azide showed the greatest stacking between the benzoyl group and the p-methoxyphenyl ring, but less stacking than was observed in the crystallographic structure. The orientational preferences of these benzo[b]thiophene ligands with the estrogen receptor were analyzed with the receptor volume mapping technique, a method based on the correspondence of the hydroxyl groups and the volume that the benzo[b]thiophene compound shares with a composite molecular volume of high-affinity estradiol-type ligands (the receptor excluded volume, RExV). If the benzo[b]thiophene nucleus is overlapped with the steroid AB rings, the best overlap with the RExV is achieved, but there is poor correspondence of the hydroxyl groups. An orientation and conformation in which the benzoyl group of the 3-benzoyl-2-aryl-benzo[b]thiophenes occupies a 7 alpha-like position relative to the steroid produces both ample volume overlap with the RExV and close approximation of the hydroxyl groups and is presented as the putative bioactive conformation.

Ultrasonographically guided biopsy of small intra-abdominal masses

Ultrasonography (US) has traditionally been considered inferior to computed tomography (CT) for guidance in fine-needle aspiration biopsy (FNAB) of small intra-abdominal masses. To assess the validity of this view, the results obtained for 58 consecutive patients referred for US-guided FNAB of intra-abdominal masses of diameter 25 mm or less were retrospectively analysed. In each case two to four (usually three) aspirations were initially performed with a 22-gauge needle; sufficient tissue for diagnosis was obtained in 53 of the 58 cases (91%). The procedure had to be repeated in the other five patients to acquire diagnostic tissue. Apart from some minor abdominal pain, no complications were encountered. Proof of the cytologic diagnosis was available for 49 of the 58 patients (84%)--from histologic examination in 22 cases and from the appropriate clinical and radiologic course in 27. A sensitivity of 95% and a specificity of 90% for the technique were found for the patients for whom adequate follow-up information was available. The authors conclude that FNAB of intra-abdominal masses measuring 25 mm or less can be accurately and safely performed under US guidance.

Acute effects of inhaled salbutamol on the metabolic rate of normal subjects

BACKGROUND

This study was designed to investigate the contribution of inhaled salbutamol to the increase in resting metabolic rate found in patients with chronic airflow limitation who were receiving bronchodilator therapy.

METHODS

The resting metabolic rate of 10 normal subjects (age 20-47 years, weight 42-105 kg, seven men) was studied after inhalations of salbutamol or placebo. An open canopy method of indirect calorimetry was used to measure resting oxygen consumption (VO2) and resting carbon dioxide production (VCO2). Subjects inhaled two, four, eight, or 12 puffs (100 micrograms/puff) of salbutamol or placebo in a double blind manner. Recordings of VO2 and VCO2 were made after inhalation of the four doses of salbutamol or placebo, integrated over one hour, and compared.

RESULTS

VO2 and VCO2 increased in a dose dependent manner after inhaled salbutamol with a maximum effect at five minutes after inhalation. After four puffs, VO2 was 203 and 188 ml/kg/h for salbutamol and placebo respectively. After eight puffs, VO2 was 207 and 185 and VCO2 was 167 and 155 ml/kg/h. After 12 puffs, VO2 was 220 and 190 with a VCO2 of 181 and 168 ml/kg/h. Twelve puffs of salbutamol increased the mean (SE) respiratory quotient from 0.85 (0.01) to 0.93 (0.04) at five minutes indicating an increase in ventilation in excess of metabolic demand. Mean heart rate increased in parallel with VO2.

CONCLUSION

Inhaled salbutamol significantly increases resting metabolic rate in a dose dependent manner.

Modification of the thermogenic effect of acutely inhaled salbutamol by chronic inhalation in normal subjects

BACKGROUND

Acute inhalation of clinical doses of salbutamol in normal volunteers increases resting metabolic rate by up to 20% above control values. This study was designed to see if chronic treatment with salbutamol causes a sustained increase in metabolic rate and whether it modifies the acute thermogenic response to the drug.

METHODS

The effects of chronic inhaled salbutamol on resting oxygen consumption (VO2) and carbon dioxide output (VCO2) were studied in seven normal subjects (age 20-47 years, weight 52-105 kg, five men). An open canopy method of indirect calorimetry was used to measure VO2, VCO2, and respiratory quotient (RQ). Subjects inhaled two puffs of salbutamol or placebo four times a day in a double blind manner. Measurements of resting VO2 and VCO2 after 10 days of salbutamol were compared with the values after 10 days of placebo and with those taken at the start of the study. At the end of each treatment period subjects inhaled eight puffs (800 micrograms) of salbutamol and the acute effects on VO2, VCO2 and RQ were monitored for one hour.

RESULTS

Resting VO2, VCO2, and RQ were not significantly different at the end of the salbutamol and placebo periods but the acute response to eight puffs of salbutamol was abolished by regular inhalation. The mean VO2 integrated over one hour after 800 micrograms salbutamol given acutely was different (241.3 and 210.7 ml/kg/h in the placebo and salbutamol groups respectively). Differences were not significant between placebo and salbutamol groups for changes in VCO2, heart rate, blood pressure, and RQ after acute inhalation.

CONCLUSION

Regular treatment with inhaled salbutamol (800 micrograms/day) does not cause a sustained increase in resting metabolic rate but prevents the increase in VO2 that occurs after acute inhalations in normal subjects.

Atypical hepatic hemangioma: a suggestive sonographic morphology

A retrospective review of the sonographic appearances of 29 proved atypical hemangiomas in 29 patients and a prospective study of the predictive capacity of these features were performed. The main confirmatory imaging examinations were computed tomography and technetium-labeled red blood cell radioisotope scanning with single photon emission computed tomography. The retrospective review showed that all tumors were solid. Twenty-seven tumors had an echogenic border, seen as a thick echogenic rind (n = 15) and a thin rim (n = 12). Unlike typical hemangiomas, which have a uniformly increased echogenicity relative to normal liver, all 29 tumors had an internal echo pattern that was at least partially hypoechoic. These morphologic criteria (a solid tumor with an echogenic border and partially hypoechoic internal pattern) were then prospectively applied to all hepatic tumors detected with sonography during a 6-month period. Fifteen lesions with these features were identified from among more than 5,000 abdominal scans. Twelve of these lesions were confirmed as, and two were presumed to be, cavernous hemangiomas; in one lesion, the diagnosis was false-positive. Recognition of these atypical features should increase suspicion of the presence of hemangiomas on sonograms.

Applications of electrospray ionization mass spectrometry to neutral organic molecules including fullerenes

The use of electrospray ionization mass spectrometry (ESI/MS) for the detection of neutral organic molecules becomes possible by their derivation with specific ESI/MS tagging reagents that have either proton or metal ion binding sites. We used the neutral crown ether group in several reagents to attach a metal binding site to substrate molecules. Application of this method to steroids, amino acids, vitamin D, fatty acids, and fullerenes is described. Besides characterization, tagged molecules can be used for studying organic reactions by ESI/MS. This work demonstrates that ESI/MS provides a unique window on fullerene solution chemistry. ESI/MS is not only an excellent tool for the analysis of biopolymers but is also useful for studying the organic chemistry of small neutral molecules.

Use of MEDLINE by physicians for clinical problem solving

OBJECTIVE

To understand the ways in which computer-mediated searching of the biomedical literature affects patient care and other professional activities. Undertaken to determine the ways in which on-line access to the biomedical literature via the National Library of Medicine's MEDLINE database "makes a difference" in what physicians do when confronted with a medical problem requiring new or additional information.

DESIGN

An adaptation of the Critical Incident Technique used to gather detailed reports of MEDLINE search results that were especially helpful (or not helpful) in carrying out the individual's professional activities. The individual physician was the source of the patient care incident reports. One thousand one hundred fifty-eight reports were systematically analyzed from three different perspectives: (1) why the information was sought; (2) the effect of having (or not having) the needed information on professional decisions and actions; and (3) the outcome of the search.

PARTICIPANTS AND SETTING

Telephone interviews were carried out with a purposive sample of 552 physicians, scientists, and other professionals working in a variety of clinical care and other settings. Of these, 65% were direct users of MEDLINE throughout the United States, and 35% had MEDLINE searches conducted for them either at a major health sciences center or in community hospitals.

RESULTS

Three comprehensive and detailed inventories that describe the motivation for the searches, how search results affected the actions and decisions of the individual who initiated the search, and how they affected the outcome of the situation that motivated the search.

CONCLUSIONS

MEDLINE searches are being carried out by and for physicians to meet a wide diversity of clinical information needs. Physicians report that in situations involving individual patients, rapid access to the biomedical literature via MEDLINE is at times critical to sound patient care and favorably influences patient outcomes.

A controlled trial of two forms of self-management education for adults with asthma

PURPOSE

Excess morbidity and mortality due to asthma, aggravated by demonstrably poor patient self-management practices, suggest the need for formal patient education programs. Individual and group asthma education programs were developed and evaluated to determine their cognitive, behavioral, and clinical effects.

PATIENTS AND METHODS

We compared changes in asthma symptoms, utilization of medical services, knowledge about asthma, metered-dose inhaler (MDI) technique, and self-management behaviors for 323 adult Kaiser Permanente patients with moderate to severe asthma who were randomly assigned to small-group education, individual teaching, or 1 of 2 control conditions--an information (workbook) control or usual control (no formal asthma education). Data were collected from patients by questionnaire, diary, and physical examination at enrollment and at 5 months and 1 year after intervention. Medical record data on these patients were abstracted for a total 3-year period, from 1 year before to 2 years after enrollment.

RESULTS

Compared with the usual control, the self-management education programs were associated with significant improvements in control of asthma symptoms (reduced "bother" due to asthma and increased symptom-free days), MDI technique, and environmental control practices. Small-group education also was associated with significant improvements in physician evaluation of the patients' asthma status and in patients' level of physical activity. For both group and individual education recipients, improvement in MDI technique was positively correlated with improved control of symptoms; however, the degree of improvement in symptoms was greater than that which could be accounted for on the basis of improvement in MDI technique alone. The time course over which changes occurred in the various outcome measures suggests the mechanism by which education resulted in improvement in the patient's status. Significant improvements in MDI technique and environmental control practices were manifest immediately following education (5-month follow-up) and at the 1-year follow-up. Significant improvements in symptom measures were not apparent until the 1-year follow-up. The rate of utilization of medical care for acute exacerbations decreased between baseline and the 2-year follow-up period, but this decrease did not differ significantly among treatment conditions. However, there was a trend toward greater reduction in patients receiving small-group education. An ad hoc finding of a significant difference favoring small-group education between the baseline and the second follow-up year acute visit rates was observed. This result must be regarded as tentative, since it is not clear that unambiguous statistical significance is attained in the light of multiplicity issues. However, this trend is consistent with the antecedent benefits of the small-group education, and appears to warrant further investigation.

CONCLUSIONS

Carefully designed asthma education programs for adults can improve patients' understanding of their condition and its treatment and increase their motivation and confidence that the condition can be controlled, thereby increasing their adherence to the treatment regimen and management of symptoms, and, in turn, improving control of symptoms. Both small-group education and individual education were associated with significant benefits, but the group program was simpler to administer, better received by patients and educators, and more cost-effective. The results show promise for improving clinical outcomes, through well-designed educational programs, for patients with asthma and other chronic health problems.

Exploring norms and beliefs related to AIDS prevention among California Hispanic men

A focus-group study gathered qualitative information from Hispanic males in California regarding ethnic factors that might enhance or interfere with AIDS prevention efforts. A predominantly working-class convenience sample of 75 men aged 18-40 participated in seven groups of 10-12 participants each. Three groups were composed of single men, three of married men and one was composed of homosexual and bisexual men. Four groups included only participants born outside the United States; and Spanish was the preferred language in five of the groups. Evaluation of the discussions indicates that while AIDS awareness is high among this population, condom use is sporadic. Few participants knew that someone infected with the human immunodeficiency virus could appear healthy; most believed they could easily determine if a woman is risky by her appearance or social standing. Although many participants thought HIV could be transmitted through casual contact, the homosexual and bisexual men were more likely to acknowledge that they were at some risk of infection; most of the heterosexual men did not perceive themselves as being at risk, even those who engaged in sex with prostitutes or women they met at bars. The participants had ambivalent attitudes toward women who suggested condom use and were often reluctant to initiate condom use themselves. Religion did not seem to play a major role in the men's attitudes about AIDS, sexuality and condom use.

A synthesis of 7 alpha-substituted estradiols: synthesis and biological evaluation of a 7 alpha-pentyl-substituted BODIPY fluorescent conjugate and a fluorine-18-labeled 7 alpha-pentylestradiol analog

In an effort to assist in the preparation of ligands for the study of the estrogen receptor (ER), we have developed a new synthesis of 7 alpha-substituted estradiols. The key step in the synthesis involves a copper-catalyzed, alpha-selective, 1,6-conjugate addition of 4-pentenyl magnesium bromide to a suitably protected 6-dehydrotestosterone derivative. Desaturation and then reductive aromatization of the resulting 7 alpha-pentenyl androgen gave the 7 alpha-pentenylestradiol in good yields. The alpha-stereoselectivity of this addition in the testosterone series, compared with the 19-nortestosterone series, is significantly improved by the presence of the C-19 methyl group, which shields the beta face from attack. A key intermediate was functionalized further by substitution with fluorine-18 to provide a potential imaging agent for positron emission tomography, and by conjugation with a BODIPY (Molecular Probes Inc., Eugene, OR, USA) fluorophore to make a fluorescent probe for the estrogen receptor. The synthesis and biological evaluation of these analogs is presented, as well as a discussion of the improvements in the synthetic procedure.