Enhancement of achievement and attitudes through individualized learning-style presentations of two allied health courses

This investigation analyzed the effects of the instructional resource Programmed Learning Sequence (PLS) on the achievement and attitudes of college students and correlated the findings with the individuals' learning styles. The subjects were enrolled in Sonography I and Cross-Sectional Anatomy in a college of health-related professions. Both classes were administered the Productivity Environmental Preference Survey to identify learning-style strengths, and alternately presented with lessons using a PLS in a book format and traditional lectures. The sonography class also was exposed to a PLS in multimedia computer format. The Semantic Differential Scale measured the students' attitudes comparing the instructional methods experienced, and class examinations measured content mastery. In both classes, examination scores were significantly higher (effect size for the sonography class was 1.42; for the anatomy class, 0.63) and students' attitude scores were significantly higher when PLS rather than the traditional method was used. In the sonography class, achievement was significantly higher with the book PLS than with the computer PLS (effect size, 1.11). Significant correlations emerged between learning-style elements and achievement: students who preferred learning with the book PLS required more quiet in the environment than did those who preferred the computer PLS; students who preferred learning traditionally and with the computer PLS required more light than those preferring the book PLS; and students who preferred learning with an authority figure favored the traditional method. Examination of the data for other correlations between learning-style preferences and attitudes using the book PLS also revealed many other significant findings, demonstrating its ability to accommodate diverse styles.

Factors related to family therapists' breaking confidence when clients disclose high-risks-to-HIV/AIDS sexual behaviors

This national survey of 309 marriage and family therapists examined what therapists do when their HIV-positive clients disclose that they are engaging in high-risk sexual behavior. The participants were given vignettes in which a fictitious client told the therapist about engaging in unprotected sex. Although the basic situations were the same, the client variables of age, gender, race, sexual orientation, and HIV status were systematically varied. The participants were more likely to break confidence regarding unsafe sex practices when their clients were male, young, gay, or African American. Moreover, therapists who were more likely to disclose were older, female, had less experience with gay/lesbian populations, were Catholic, were very religious, and were more likely to practice in urban areas. The authors discuss the implications of these and other findings.

Tn5/IS50 target recognition

This communication reports an analysis of Tn5/IS50 target site selection by using an extensive collection of Tn5 and IS50 insertions in two relatively small regions of DNA (less than 1 kb each). For both regions data were collected resulting from in vitro and in vivo transposition events. Since the data sets are consistent and transposase was the only protein present in vitro, this demonstrates that target selection is a property of only transposase. There appear to be two factors governing target selection. A target consensus sequence, which presumably reflects the target selection of individual pairs of Tn5/IS50 bound transposase protomers, was deduced by analyzing all insertion sites. The consensus Tn5/IS50 target site is A-GNTYWRANC-T. However, we observed that independent insertion sites tend to form groups of closely located insertions (clusters), and insertions very often were spaced in a 5-bp periodic fashion. This suggests that Tn5/IS50 target selection is facilitated by more than two transposase protomers binding to the DNA, and, thus, for a site to be a good target, the overlapping neighboring DNA should be a good target, too. Synthetic target sequences were designed and used to test and confirm this model.

Benign fat necrosis simulating bilateral breast malignancy after reduction mammoplasty

Fat necrosis follows many forms of trauma to the breast, including surgery. In unusual cases, it may be extensive enough to present as a palpable mass on physical examination with mammographic features suggestive of cancer. In these instances, regardless of patient age, surgical history, or multifocality, a biopsy must be done to exclude carcinoma. We describe a young woman who was evaluated for bilateral breast masses with highly suspicious imaging characteristics 2 years after having reduction mammoplasty.

Chemopreventive effects of 2-(allylthio)pyrazine on hepatic lesion, mutagenesis and tumorigenesis induced by vinyl carbamate or vinyl carbamate epoxide

2-(Allylthio)pyrazine (2-AP), synthesized for its possible use as a hepatoprotective agent, has been found to selectively inhibit rat hepatic cytochrome P450 2E1 (Kim et al., Biochem. Pharmacol., 53, 261-269, 1997), while it enhances the activities of phase II detoxification enzymes such as glutathione S-transferase and epoxide hydrolase. As part of a program in evaluating the chemopreventive potential of 2-AP, we have determined its effects on hepatotoxicity, mutagenicity and tumorigenicity of vinyl carbamate (VC), a prototypic hepatocarcinogen preferentially activated by P450 2E1 to the ultimate carcinogenic metabolite vinyl carbamate epoxide (VCO), which undergoes detoxification by glutathione conjugation and oxirane hydrolysis. Administration of 2-AP (100 mg/kg body wt) to male Sprague-Dawley rats by gavage, 2 days, 1 day and 4 h prior to VC or VCO, markedly ameliorated the hepatotoxicity of these compounds as determined by decreased serum aspartate aminotransferase and alanine aminotransferase activities. Furthermore, 2-AP pre-treatment significantly suppressed the VC-induced hepatocarcinogenesis in infant male B6C3F1 mice. In a separate experiment, the multiplicities of skin tumors formed in female ICR mice treated with 5.8 micromol of VC or VCO were inhibited 58 and 70%, respectively, by pre-treatment with 2-AP by oral administration. The mutational spectrum of ras-oncogene in papillomas was not altered by 2-AP pre-treatment. 2-AP also inhibited the mutagenicity of VC in the Salmonella-microsome assay. Taken together, these findings suggest that 2-AP is a potential chemopreventive agent.

Delivery of ivermectin by injectable microspheres

A bioabsorbable, injectable microsphere formulation containing ivermectin in poly-(lactide-co-glycolide) copolymer (PLA/PGA) was developed to provide long-lasting delivery of the drug for control of livestock pests. A solvent-evaporation technique was used to produce the spherical beads containing approximately 30% ivermectin and ranging in size from 25-250 microns. The pattern of delivery of the drug into the blood stream of Spanish goats was characterized for a 50:50 PLA/PGA, a 90:10 PLA/PGA copolymer formulation, and a PLA monomer formulation. When the 50:50 PLA/PGA formulation was used in cattle at the rate of 2 mg (AI)/kg body weight, 2 peaks of 45-50 ppb of ivermectin in serum were observed. The 1st peak was at approximately 1 wk after injection and the 2nd peak, which was broader than the 1st, occurred at approximately 6-7 wk after injection. Percentage of inhibition of estimated larvae for the lone star tick, Amblyomma americanum (L.), placed on treated cattle was 100% for the first 8 wk after injection and was 75, 57, 46 and 44% for wk 9, 10, 11, and 12, respectively. The treatment provided 98-100% control of larval horn flies, Haematobia irritans (L.), in the manure of treated cattle for 10 wk. The bioassay results against lone star ticks and larval horn flies were in agreement with the serum concentration data. The injectable microsphere formulation of ivermectin should be useful in a variety of other applications ranging from the control of Boophilus spp. ticks in south Texas to heartworms in pets.

Locomotor advantages of Neandertal skeletal morphology at the knee and ankle

We quantified Neandertal knee extensor and ankle plantarflexor moments to determine whether differences between Neandertal and recent human skeletal morphology represent important functional differences. Neandertal skeletal differences in the patella, tibial tuberosity, and calcaneus were used to modify a computer model of recent humans to calculate the moment arms and moments of Neandertal knee extensor and ankle plantarflexor muscles. We also conducted sensitivity studies on the effect of musculotendon parameters on the Neandertal moments. As expected, we found that Neandertal moment arms were greater than recent humans at the ankle (122-141%); however, the magnitude of the increase was not well-predicted from measurements of size differences between Neandertal and recent human skeletons. At the knee, Neandertal moment arms were greater than those of recent humans in the locomotor range (108%) but less so at more flexed knee angles (102%). Not all Neandertal skeletal adaptations at the knee contributed to increased moment arm. Knee extensor moments were enhanced in the Neandertal models in the locomotor range (111%), regardless of musculotendon parameters. At the ankle, however, Neandertal plantarflexor moment was greater than that of recent humans (149-200%) at all joint angles only if muscle fiber length increased proportionately with moment arm. Our results demonstrate that Neandertal skeletal morphology, compared to that of recent humans, generated greater moments at both the knee and ankle in the locomotor range but not at higher angles of knee flexion or ankle plantarflexion.

Inhibition of vinyl carbamate-induced hepatotoxicity, mutagenicity, and tumorigenicity by isopropyl-2-(1,3-dithietane-2-ylidene)-2-[N-(4-methylthiazol-2- yl)carbamoyl]acetate (YH439)

Isopropyl-2-(1,3-dithietane-2-ylidene)-2-[N-(4-methylthiazol -2-yl)carbamoyl]acetate (YH439) is a novel dithioylidene malonate derivative developed for the treatment of hepatic injury. The compound has been found to down-regulate the expression of hepatic cytochrome P-450 2E1 (CYP2E1) at the transcriptional level (8). Certain organosulfur compounds present in garlic elicit protective effects on chemically induced carcinogenesis and mutagenesis and their chemopreventive activities are associated in part with inhibition of CYP2E1. As part of a program to determine the likely chemopreventive potential of YH439, we initially examined its effects on hepatotoxicity induced by vinyl carbamate (VC), a proximate carcinogen that is preferentially bioactivated by CYP2E1. A single i.p. injection of VC (125 mg/kg body wt) to male Sprague-Dawley rats resulted in severe hepatic lesions as demonstrated by elevated levels of serum enzymes such as alanine aminotransferase and aspartate aminotransferase. Histopathological evaluation of liver sections from VC-treated animals revealed that the hepatic damage mainly consisted of centrilobular necrosis with sinusoidal congestion. Oral administration of YH439 (200 mg/kg body wt) to male Sprague-Dawley rats 2 days, 1 day and 4 h prior to VC completely prevented the hepatic damage caused by this carcinogen. In another experiment, rat hepatic microsome-mediated bacterial mutagenicity of VC was suppressed by YH439 in a dose-related manner. Furthermore, pretreatment of female CD-1 mice with YH439 by gastric intubation resulted in diminution of VC-induced skin carcinogenesis.

Pancreaticopleural fistula. An unusual cause of persistent unilateral pleural effusion

There are a myriad of causes of a large persistent pleural effusion. Pancreaticopleural fistula is a rare entity seldomly included in the above differential. As it usually presents with thoracic rather than abdominal symptoms, a combination of imaging modalities, including chest radiography (CXR), computerized tomography (CT) and endoscopic retrograde cholangiopancreatography (ERCP) is essential in obtaining the diagnosis.

Improving managed care through coding, monitoring, and trending quality-of-care concerns

With the rise of managed care, purchasers and payers are increasingly demanding value in healthcare. Traditionally, patient satisfaction surveys and focus groups have been used to elicit information regarding customers' perspectives. This article explores the use of an inexpensive alternative methodology--that of monitoring quality-of-care concerns and complaints. A nomenclature and a process for tracking, trending, and reporting quality-of-care issues are detailed; they encompass both the patient's and the provider's perception of a specific care experience. This methodology promotes the use of quantifiable data to support strategic planning and compliance with National Committee for Quality Assurance accreditation standards.

Predicting the rates of success and complications of computed tomography-guided percutaneous core-needle biopsies of the thorax from the findings of the preprocedure chest computed tomography scan

The authors attempted to determine whether the anatomic characteristics of thoracic lesions and the surrounding lung field, as assessed by the preprocedure chest computed tomography (CT) scan, can assist in predicting the yield of complications or positive results of pathologic examination resulting from percutaneous core-needle biopsies (PCNB). The pathologic diagnoses and procedural complications of 50 consecutive thoracic PCNBs (43 men, age range 19-81 years) performed under the guidance of a single operator (J.A.M.) were recorded. Prebiopsy chest CT findings, including the size, depth, location, and border appearance of the lesion, as well as presence or absence of adjacent emphysema, interstitial fibrosis, bullae, pleural effusions, and the age and smoking history of the patient were correlated with the biopsy results and any ensuing complications. The pathologic analysis in 42 patients (84%) was specific enough to positively impact patient management, with 29 malignant and 13 benign entities. The imaging variables that predicted obtaining adequate tissue for pathologic diagnosis were most importantly large size (especially >35 mm), although irregular lesion margins and increased depth were significant as well. Seven patients (14%) experienced a pneumothorax, only one of which (2%) was symptomatic and required thoracostomy. All patients experiencing a pneumothorax had CT evidence of emphysema or interstitial fibrosis and all biopsied masses in these individuals had spiculated borders, with six (86%) in an anterior location and only one involving the pleural surface. We conclude that the preprocedure CT scan can delineate several characteristics of both the patient and the lesion to be biopsied that can assist in predicting the rates of successful tissue retrieval or pneumothorax during PCNBs.

Fetal alcohol exposure and temporal vulnerability regional differences in alcohol-induced microencephaly as a function of the timing of binge-like alcohol exposure during rat brain development

In humans, microcephaly (small head for body size) is a common feature of fetal alcohol syndrome. An analogous measure, termed microencephaly (small brain for body size), can be used for evaluating the detrimental effects of the differential timing of alcohol exposure on brain development in animal model systems. Timed-pregnant rats were exposed to binge-like alcohol during either the first 10 days (first trimester equivalent) or second 10 days of gestation (second trimester equivalent), or the combination of first and second trimesters equivalent for prenatal treatments. Offspring from some of the animals exposed to alcohol during the combined first and second trimesters equivalent were raised artificially from postnatal day (P) 4 through P9 (part of the third trimester equivalent), and also received binge-like alcohol during this period, producing animals that were exposed to alcohol during all three trimesters equivalent. Offspring from untreated dams were also raised artificially and received alcohol only from P4 to P9, thus creating animals that were exposed to alcohol only during part of the third trimester equivalent. All pups were perfused on P10. Appropriate controls (nutritional and normally reared) were used for every alcohol treatment combination. Peak blood alcohol concentrations were not different among the treatment groups for a given sampling time. Significant somatic growth deficits occurred in offspring exposed to alcohol for the equivalent of all three trimesters, compared with offspring exposed to alcohol during other periods. Brain growth in offspring also was significantly affected by the timing of alcohol exposure. The whole brain, forebrain, and cerebellum to body weight ratios of pups exposed to alcohol during the third trimester had more significant brain growth deficits than pups in groups exposed to alcohol during other times of brain development. Although alcohol exposure during the third trimester had a significant detrimental impact on overall brain growth, significant differences in temporal vulnerability were also found for the brainstem to body weight ratios. Offspring of dams exposed to alcohol during the first trimester had the same magnitude of deficit as those exposed to alcohol during the third trimester, and those two groups were significantly deficient compared with the groups exposed to alcohol at other times, suggesting some differential vulnerability of this region to alcohol-induced injury at different times of development. This study is the first thorough examination of microencephaly and gross regional vulnerability of the developing brain as related to temporal factors of alcohol exposure in an animal model system, and the results support and expand on the findings of the available clinical literature. Furthermore, our results substantiate claims that the cessation of alcohol before the third trimester can lessen the severity of some alcohol-related birth deficits.

Prolonged production of NADPH oxidase-corrected granulocytes after gene therapy of chronic granulomatous disease

Little is known about the potential for engraftment of autologous hematopoietic stem cells in human adults not subjected to myeloablative conditioning regimens. Five adult patients with the p47(phox) deficiency form of chronic granulomatous disease received intravenous infusions of autologous CD34(+) peripheral blood stem cells (PBSCs) that had been transduced ex vivo with a recombinant retrovirus encoding normal p47(phox). Although marrow conditioning was not given, functionally corrected granulocytes were detectable in peripheral blood of all five patients. Peak correction occurred 3-6 weeks after infusion and ranged from 0.004 to 0.05% of total peripheral blood granulocytes. Corrected cells were detectable for as long as 6 months after infusion in some individuals. Thus, prolonged engraftment of autologous PBSCs and continued expression of the transduced gene can occur in adults without conditioning. This trial also piloted the use of animal protein-free medium and a blood-bank-compatible closed system of gas-permeable plastic containers for culture and transduction of the PBSCs. These features enhance the safety of PBSCs directed gene therapy.

Quantifying osteoarthrotic hip incongruence. An approach to optimizing osteotomies

Osteoarthrosis of the hip may be treated by osteotomy, but surgeons report variable results, and there is no consensus regarding which method to use in choosing the type of osteotomy. The authors defined three biomechanical measures of hip incongruence (characteristic point locus, joint space, and contact region) and developed a two-dimensional frontal plane model to compute joint incongruence over the joint range of motion during normal activities of daily living. The preoperative measures were calculated for 38 patients who had undergone osteotomy at least 5 years earlier. The authors calculated the measures throughout a functional range of motion after 13 stimulated varus or valgus osteotomies. A logistic regression analysis determined which, if any, of the three measures, in conjunction with other clinical variables, correctly predicted outcome. The average values for the characteristic point locus, joint space, and contact region measures ranged from 0.260 cm to 2.127 cm, 0.963 cm2 to 9.327 cm2, and 0.063 cm to 4.230 cm, respectively. Unimodal behavior between two of the three measures (joint space and contact region) and osteotomy angle were observed, suggesting these two would be the most useful in predicting an optimal osteotomy. The most significant independent variable predicting clinical outcome was the joint space measure. This supports the potential of an optimization approach for determining the best angle for a hip osteotomy.

Disparate effects of antidiabetic drugs on arterial contraction

Type II diabetic patients and others with insulin resistance are at risk for development of hypertension characterized by elevated peripheral vascular resistance and loss of insulin's normal vasodilating activity. Oral antidiabetic drugs have recently been recognized to have disparate effects on arterial pressure in such patients and in related rodent models. Sulfonylureas (e.g., glyburide), which stimulate insulin secretion, have been reported either to increase or not to affect arterial pressure, whereas nonsulfonylurea agents with insulin-sensitizing properties, the biguanide metformin and various thiazolidinediones (eg, pioglitazone), have been reported to decrease arterial pressure in humans and rodents. To help elucidate these disparate effects, we investigated these agents for direct actions on arterial vascular contractility and its sensitivity to insulin. Preincubation of intact rat tail arterial tissue rings for 2 hours with known therapeutically effective antidiabetic concentrations of metformin and pioglitazone significantly attenuated the force of contractions produced by either potassium (membrane depolarization) or norepinephrine ([NE] adrenergic receptor activation). Glyburide did not influence these contractions. Preincubation with metformin also induced an attenuating (vasodilating-like) action of insulin on arterial tissue rings contracted by potassium. Conversely, glyburide induced an accentuating action of insulin on potassium-mediated contractions. These results are consistent with measures of vascular function obtained in the past after oral administration of the drugs, which suggested but did not prove that they may exert direct effects on arterial vascular contractility. Thus, metformin and thiazolidinediones may decrease arterial pressure partly by direct vasorelaxant mechanisms, with metformin having an additional effect of inducing vasorelaxation by insulin. In contrast, sulfonylureas may directly induce a paradoxical vasoconstrictor response to insulin.

Randomized trial comparing the tolerability of sargramostim (yeast-derived RhuGM-CSF) and filgrastim (bacteria-derived RhuG-CSF) in cancer patients receiving myelosuppressive chemotherapy

A prospective, randomized, double-blind, multicenter study in cancer patients receiving myelosuppressive chemotherapy was undertaken to evaluate and compare the tolerability of sargramostim (yeast-derived recombinant human granulocyte-macrophage colony-stimulating factor, RhuGM-CSF) and filgrastim (bacteria-derived recombinant human granulocyte colony-stimulating factor, RhuG-CSF) in the prophylaxis or treatment of chemotherapy-induced neutropenia. In all, 137 evaluable patients received sargramostim (300 micrograms; 193 mg/m2) or filgrastim (481 mg; 7 mg/kg) once daily by self-administered s.c. injection, usually beginning within 48 h after completion of chemotherapy. With the exception of a slightly higher incidence of grade 1 fever (< 38.1 degrees C) with sargramostim, there were no statistically significant differences in the incidence or severity of local or systemic adverse events possibly related to the growth factors. Although the study was not designed to evaluate efficacy directly, there also were no statistically significant differences between treatment groups in total days of growth factor therapy, days of hospitalization, or days of i.v. antibiotic therapy during the treatment period. Both sargramostim and filgrastim were comparably well tolerated when given by s.c. injection in this group of patients, and no clinically significant differences between the growth factors were demonstrated.

Putative folding pathway of insulin-like growth factor-I

Insulin-like growth factor-I (IGF-I) has three disulfide bonds and refolding of the fully reduced molecule generates varying ratios of correctly (PII) and incorrectly (PI) folded forms via several intermediates. All of the intermediates have the disulfide bond between Cys18 and 61 formed, indicating that formation of this disulfide is the first step in refolding. In order to further understand the refolding pathway, two intermediate froms, PIII with the additional disulfide Cys(6/47) formed and PIIIa with Cys(6/48) formed, were isolated. The oxidation of the remaining Cys48 and 52 in PIII and Cys47 and 52 in PIIIa would lead to PI and PII, respectively; however, air oxidation of these resulted in a rapid reshuffling into other intermediates as well as folding into the fully oxidized forms, and this occurred whether refolding was started with PIII or PIIIa. When oxidation occurred in the presence of an excess of oxidized glutathione, the predominant species generated were various glutathione adducts regardless of the initial intermediate form, indicating that formation of the last disulfide bond is not a favorable process relative to disulfide exchange when excess disulfides from oxidized glutathione are present. Interestingly, if 80 microM copper sulfate, an oxidant, is added to the refolding buffer, PIII resulted in formation of the PI form alone, whereas PIIIa resulted in the PII form alone. It was concluded from these results that the intermediate forms of IGF-1 can rapidly reshuffle between different disulfide structures, and that formation of the last disulfide bond is not as favorable a process as the conversion to other intermediates. The oxidation to form the last disulfide bond in PIII or PIIIa is accelerated and hence the interconversion to other intermediates is kinetically minimized only in the presence of copper sulfate. It appears, therefore, that the two intermediate forms, PIII and PIIIa, are the precursors of the corresponding fully oxidized forms, but their conversions are not energetically a favorable process.

Renal responses to sodium restriction in patients with early diabetes mellitus

Increased GFR and decreased renal vascular resistance are common renal hemodynamic changes in persons with early, uncomplicated, insulin-dependent diabetes mellitus. It has been hypothesized that excess total-body sodium in patients with diabetes contributes to the renal vasodilation, possibly by suppressing vasoconstricting neurohormonal systems. This study was undertaken to examine whether sodium restriction could normalize these renal abnormalities. Subjects were 12 male patients with uncomplicated insulin-dependent diabetes mellitus (duration, < 5 yr). Results were compared with those of an age- and gender-matched control group. All subjects received either a high-sodium diet (200 mmol/day) or a sodium-restricted diet (20 mmol/day) for 7 days, according to a randomized crossover protocol. GFR and RPF were measured using inulin and para-aminohippurate clearance techniques, respectively. Subjects with diabetes were maintained euglycemic during the clearance measurements. GFR was significantly higher in the diabetic group than in the control group with sodium repletion (124 +/- 4 versus 107 +/- 8 mL/min/1.73 m2; P = 0.03), and renal vascular resistance was significantly reduced (94 +/- 6 versus 107 +/- 17 mm Hg/L/min; P = 0.05). In response to sodium restriction, the hematocrit increased significantly in both groups, as did PRA and aldosterone, although responses in the diabetic group were somewhat blunted, indicating persisting volume expansion. Despite this humoral activation, sodium restriction had little effect on renal hemodynamic function in control subjects. In the diabetic subjects, this maneuver appeared to exacerbate the underlying renal abnormalities, with the GFR increasing to 131 +/- 4 mL/min/1.73 m2 (P = 0.05) and the renal vascular resistance declining to 73 +/- 5 mm Hg/L/min (P = 0.001). These data indicate that, rather than correcting renal hyperperfusion, sodium restriction exacerbates these characteristic abnormalities, suggesting that mechanisms other than suppression of vasoconstrictor activity are operative in the underlying renal hemodynamic abnormalities of early, uncomplicated, insulin-dependent diabetes mellitus.