Comparison of the fluorescence and conformational properties of smooth and striated tropomyosin

In contrast to previous conformational studies with rabbit skeletal and cardiac tropomyosins, (i) when the cysteine side chains of chicken gizzard tropomyosin were reacted with 5,5'-dithiobis(2-nitrobenzoate), an interchain disulfide cross-link was not produced, (ii) when they were labeled with pyrenylmaleimide , excimer fluorescence was not observed, and (iii) when they were labeled with didansylcystine , a long-lived fluorescence component did not appreciably contribute to the fluorescence decay over a large temperature range including the major unfolding transition. In addition, the temperature dependence of the ellipticity at 222 nm did not reveal a pretransition prior to the main helix unfolding transition. This indicates that gizzard tropomyosin does not exhibit a localized chain-open state in the region of its cysteine residues, analogous to that seen with cardiac and skeletal tropomyosins, nor in any other region of the molecule. As a consequence, these observations suggest that gizzard tropomyosin is more rigid than striated tropomyosin.

Papain hydrolysis of X-phenyl-N-methanesulfonyl glycinates: a quantitative structure-activity relationship and molecular graphics analysis

The hydrolysis of 32 X-phenyl-N-methanesulfonyl glycinates by papain was investigated. It was found that the variation in the Michaelis constants could be rationalized by the following correlation equation: log 1/Km = 0.61 pi '3 + 0.46 MR4 + 0.55 sigma + 2.00 with a correlation coefficient of 0.945. In this expression, pi '3 is the hydrophobic constant for the more lipophilic of the two possible meta substituents, MR4 is the molar refractivity of 4-substituents, and sigma is the Hammett constant summed for all substituents. Using this equation, we designed, synthesized, and successfully predicted Km for a new congener intended to maximize binding (1/Km). The interactions involved in enzyme-substrate binding, as characterized by the correlation equation, are interpreted using a computer-constructed color three-dimensional-graphics molecular model of the enzyme active site. The nonenzymatic hydrolysis (both acid and basic) of phenyl hippurates yield rate constants which are well correlated by Hammett equations; however, log k for both acid and alkaline hydrolysis are not linearly related to log 1/Km or log kcat/Km.

Neonatal methadone withdrawal. Effect of two treatment regimens

Thirty-one infants exposed to methadone in utero who required pharmacologic treatment for withdrawal symptoms were randomly assigned to a paregoric or phenobarbital treatment group. Seven infants had symptoms too mild to require treatment. Respiratory rate, blood pH, PCO2, systolic BP, and serum thyroxine concentrations were measured on the 4th, 7th, and 14th days of life. Platelet counts were performed on the seventh and 14th days of life, and urinary catecholamine excretion was measured on the sixth day of life. Rates of weight gain were recorded during the second and third weeks of life. With the exception of a slightly higher blood PCO2 level in the phenobarbital-treated infants on day 7, no significant intergroup differences were observed in the treated infants. Paregoric-treated infants required a significantly longer period of treatment than phenobarbital-treated infants (22 v 17 days). This may have been due, at least in part, to the prolonged half-life and relatively high blood levels of phenobarbital present after cessation of therapy.

The rate of starch hydrolysis in vitro does not predict the metabolic responses to legumes in vivo

The aim of this study was to determine whether legumes in a physical form which is rapidly digested in vitro give rise to proportionately greater metabolic responses in vivo than legumes which are slowly digested in vitro. Samples of cooked whole and ground lentils were incubated in vitro with pancreatic amylase for 30 min and the percentage starch hydrolysis determined. Grinding the lentils before cooking resulted in a 5-fold increase in the rate of starch hydrolysis (whole lentils 12.1%, ground lentils 60.9%). For the in vivo studies six healthy, young, lean subjects consumed two test meals containing 50 g starch: whole lentils and lentils that had been ground finely before cooking. Postprandial glucose and insulin responses were measured over 4 h. Peak glucose and insulin responses occurred 60 min postprandially for the whole lentils and 30 min postprandially for ground lentils. Although the increase in plasma glucose after ground lentils (1.6 mM) was significantly higher (p less than 0.025) than that after whole lentils (0.9 mM), there was no difference in the magnitude of the insulin responses. These results indicate that, unlike for cereals, the rate of intestinal starch hydrolysis is not the major factor determining the metabolic responses to legumes. By virtue of their low postprandial glucose and insulin responses, irrespective of their physical form and digestibility, legumes would appear to be ideal for inclusion in the diet of diabetics.

Anti-inflammatory and antiarthritic evaluation of acetaminophen and its potentiation of tolmetin

The data obtained from 5-day and long-term evaluations of acetaminophen (APAP) using the adjuvant arthritis rat model, demonstrated the anti-inflammatory and antiarthritic activities of APAP. The analgesic, anti-inflammatory and antiarthritic activities of tolmetin were significantly potentiated when used in combination with APAP. Inasmuch as APAP, up to 2.0 mg/kg/day, does not produce ulcerogenic effects and does not potentiate the ulcerogenic potency of tolmetin, the therapeutic safety of the APAP-tolmetin combination is much superior to tolmetin alone as determined by these preclinical evaluations. Further studies will be necessary to identify the existence of other side effects, which may or may not be potentiated, before any clinical studies can be contemplated.

A conceptual approach to the development of motivational strategies

Teachers in both general and professional education are well aware of the importance of motivation as the basis of effective teaching. Heidgerken maintains that a major problem that faces nursing educators is to select the right type of motivation and to know how to effect motivation. The authors propose a conceptual model for developing strategies to deal with motivational problems. This model is an application of Vroom's value/expectancy theory and Rotter's social learning theory, and is based on the premise that nursing faculty are in strategic positions to enhance student motivation for learning by manipulating variables that are believed to influence motivation. These suggested strategies include: enhancing student's need value by rewarding them with rewards that they value the most; increasing student's perceptions of a strong link between performance and rewards; providing students with consistent and clear role perceptions; improving student satisfaction towards learning.

Problems in teaching ethnic minority nursing students

Ethnic minority nursing students are different from the majority of white students, and approaches that nursing faculties use in teaching them must also be different. Teaching these students is sometimes viewed by many faculties as a threat. However, if difficulties are recognized early and handled efficiently, educating the ethnic minority students can instead become a challenge to the nurse educators. The authors propose some ways to deal with the existing or potential difficulties that arise from teaching these students. These suggestions are made with major emphasis on the student, the teaching process, and the curriculum. Ethnic minority students need to be helped to develop a positive self-esteem, a sense of worthiness and a feeling of equality and acceptance. Nursing faculties are charged with this responsibility and must be committed to it. Furthermore, nursing curricula need to take into account cultural diversity, to increase students' understanding of the impact of cultural diversities on health care. This paper presents a viewpoint from which important questions related to problems associated with teaching minority students, could be raised.

The selection and organization of curricular experience in nursing

Curriculum is the educational design of learning experiences for the students. Curricular experiences include course content as well as learning activities. The selection and organization of curricular experiences must also reflect the philosophy of the school. The identifying and organizing of curricular experiences begins with the analysis of curriculum objectives. The most commonly used approach in selecting learning experiences is the logical approach in which the process is treated as content in curriculum development. This paper attempts to analyse the selection and organization of the first year curricular experiences of the proposed curriculum by applying the logical approach. The proposed curriculum is designed for a 2-year diploma school of nursing. Nursing is offered as a continuum of increasing complexity throughout the three semesters of each year. The curricular framework is based on the health field concept; curricular experiences are selected and organized in accordance with this concept. Courses related to the four elements of the health field concept become mandatory classes for all students. Similarly clinical experience is organized so that a total integration of knowledge from these four elements is enhanced. The first year students study the general aspects of health and health field concept; the nursing process; helping relationships and selected skills necessary for meeting patient's physiological needs. The last semester of the first year is a synthesis practicum proposed to integrate principles and theories which the students have acquired previously and to apply them to the practice of nursing.

The effectiveness of clinical teaching: a model for self-evaluation

The most widely used process for evaluating teachers' effectiveness is student ratings. Although student ratings of teachers are vitally important in the evaluation process, self-evaluation and that of peers are equally important in accurately defining an individual's effectiveness in his/her teaching role. The model for self-evaluation of clinical teaching presented in this paper is adapted from the analysis in Jacobson's model of instruction evaluation. This model comprises three steps: the pre-active, interactive, and post-active. The pre-active step in clinical teaching includes such activities as preparing objectives for both teacher and students, and communicating them to the students before clinical practice. The interactive step in clinical teaching may be seen as the actual process of teaching in the clinical area, with its central activity as being the preparation and presentation of clinical assignments to the students. It is in this step when the teacher-student relationship is put to a real test. The post-active step is a process for finding out the extent to which the teacher has achieved the desired results. This step also entails such activities as grading assignments, evaluating students' clinical performance, and conducting post-experience clinical conference. A check list for self-evaluation of clinical teaching is included.

Representation of racial minority students in selected Canadian university schools of nursing

Several studies have suggested that the problem of inequality in educational opportunity for minority students, manifested by under-representation, prevails in American higher education. Under-representation of minority groups in schools of nursing is not an unusual problem. The dearth of information on representation of ethnic minorities in baccalaureate programmes in Canada provided the impetus for the investigators to conduct this study to: (1) explore the racial and ethnic composition of the student population in selected Canadian University Schools of Nursing; (2) determine the total number of withdrawals and graduations; and (3) establish baseline data for a follow-up study. This study was exploratory in nature. A questionnaire was designed to elicit information on enrollment, admission, withdrawal and graduation of six ethnic minority groups in the 5 year period, 1974-1978. Out of 18 schools surveyed, nine schools responded with the requested statistical information. Findings of this study supported findings of other research studies conducted in the United States in that the ethnic minorities were under-represented, and their academic survival rates were low. Statistics presented in this study should not be interpreted as conclusive. Many questions crucial to exploring and understanding the pattern of representation of racial and ethnic minority nursing students are still unanswered. A better designed, long-term study is needed.

The use of acupuncture in ophthalmology

The object of this study is to answer the question: Is acupuncture of any use in ophthalmology? Ophthalmology today can boast of 95% accuracy in diagnosis, but modern therapeutics has not caught up with diagnosis. Despite an inability to explain in modern scientific terms the healing power of acupuncture, documentation of over 500 cases treated shows that this modality can be successful in the treatment of eye diseases, especially in cases of retinitis pigmentosa, high myopia, cataracts, surgical aphakia, controlled glaucoma and re-attached ablation retinae. We notice in these cases that improvement occurs in the central acuity, and no improvement in the visual field, colorvision and nightblindness. Apparently acupuncture acts on the macula alone and not on the entire retina. Acupuncture is not intended to substitute for established medication or surgery in ophthalmology. It cannot restore a tissue or organ damaged beyond regeneration; "incurable" eye diseases per se are not cured by acupuncture. Only symptoms are relieved and dimness of vision is a symptom which can be alleviated in many cases with periodic treatment.

Scleral and choroidal calcifications in a patient with pseudohypoparathyroidism

This case report suggests that calcifications in the sclera and choroid may be a feature of pseudohypoparathyroidism and shows a calcium distribution more extensive and severe than that characteristically seen in other metabolic conditions associated with calcium deposits in the eye. Ocular ectopic calcification is a part of the more generalised ectopic soft tissue calcification seen with pseudohypoparathyroidism. Evaluation of the contribution of the terminal renal failure and uraemia to the ectopic ocular calcification would require sequential evaluation of eyes with pseudohypoparathyroidism, but without the added complication of uraemia.

Nurse--teacher behaviours in the clinical field: apparent effect on nursing students' learning

One primary source of feedback on the effectiveness of their teaching, which instructors may easily overlook, comprises of students' reactions. The purpose of this study is to identify students' perceptions of teacher behaviours, which either facilitate or hinder students' learning in the clinical field, and to determine if there is a difference in the perceptions of 1st and 2nd year students. This study is exploratory and descriptive in nature. Firstly, some research studies regarding effective clinical teaching in nursing are reviewed, followed by a discussion of the research design. The tool used for collecting data is a modified form of the critical incident technique. A description of illustrative incidents is requested within five divisions: professional competency, relationship, personal attributes, teaching methods, and evaluation of practice. A system for analysis and coding of data is then discussed. Finally, the finding of this study is presented. It would seem ot the investigator that students in 1st year are particularly sensitive to how the teacher makes them feel, whereas students in the 2nd year would seem to be more concerned with the teacher's competency in teaching. The teacher behaviours reported as helpful or hindering to students' learning, as identified by the students, are outlined.

Purification and properties of choriogonadotropin from human term placenta

Affinity chromatography has been applied successfully to the isolation of human choriogonadotropin from human term placenta. In a single step, a 57-fold purification was achieved. Evidence is presented which indicates that the product contains intact hormone as well as its free alpha-subunit. Preliminary data suggest that a variant form of alpha-subunit is also present which has serine as its N-terminal and contains relatively little arginine and proline as compared to the authentic alpha-subunit.

Quantitative microscopy of epidermoid lung carcinoma: correlation with survival time

Quantitative microscopy, including morphometry of tumor, stroma, and necrosis was used for the prognostication of pulmonary carcinoma. This was supplemented by the mitosis: necrobiosis ratio, reciprocal of cell count, and number of "apoptosis" bodies. Data for 15 short-term (4-19 mo) and 8 long-term (32-132 mo) survivors with epidermoid carcinoma were expressed as indexes. The morphometric index averaged 106.8 for short-term and 156.1 for long-term survivors, respectively. Addition of the other three indexes resulted in an average of 171.4 for short-term and 318.5 for long-term survivors. Morphometric index and the necrobiosis: mitosis ratio were of greater significance than the other two indexes. Discriminatory function analysis based on the weighted sum of the logarithms of the four indexes demonstrated their usefulness in classifying patients as short-term or long-term survivors. The error rate for the discriminant analysis was 3.5%.

Vision analysis and refractive status of youths in a juvenile detention home population

Clinical optometric findings of 633 juvenile dentention youths were statistically evaluated and compared to data from the general population. The youths had a higher referral rate of refractive errors, organic problems, and muscle in balances than the general population. Female youths exhibited a higher incidence and greater severity of myopia than males at all ages. Referral rate for astigmatism among the youths was higher than the general population although the dioptric power was in agreement with previous studies.

Operant approaches to group therapy in a school for handicapped children

In order to determine the effectiveness of operant approaches to group therapy with children with cerebral palsy or mental retardation, four boys aged between 4 years 10 months and 5 years 7 months were given a total of 23 twice-weekly 30-minute treatment sessions. After treatment there was considerably improvement in the children's attention-to-tasks and they showed some increase in social interactions, though to a lesser degree. Teacher ratings also showed some improvement in classroom behavior.

Menstrual cycle and contraceptive hormonal effects on temporal discrimination

2 groups of normal females, one group receiving synthetic oestrogen and progestogen preparations, were tested for the discrimination of temporally paired flashes on 5 occasions corresponding to standard points on the menstrual cycle. The discrimination scores were subjected to a signal-detection analysis. The results indicated lower sensory sensitivity scores for the medicated group which also failed to show the cyclical changes evidenced by the nonmedicated Ss. It is suggested that the cyclical changes paralleled the hypothetical changes in endogenous oestrogen and progesterone secretion which are nullified by the synthetic hormones.