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PubMed2004

Intestinal capacity of P-glycoprotein is higher in the juniper specialist, Neotoma stephensi, than the sympatric generalist, Neotoma albigula.

Permeability-glycoprotein (Pgp) is a membrane-bound, ATP-dependent, transport protein that excludes many cytotoxic compounds including plant metabolites and pollutants from the barrier epithelia of many tissues including the small intestine. We hypothesized that intestinal Pgp capacity would be higher in Neotoma stephensi, a specialist on Juniperus monosperma known to be high in plant toxins, than the sympatric generalist, Neotoma albigula, which consumes juniper in the field, but is unable to tolerate a high juniper diet. We measured Pgp activity as the difference in accumulation of a known Pgp substrate, digoxin, between everted sections of small intestine exposed to ethanol vehicle control and a maximal level of a known competitive inhibitor of Pgp, cyclosporin A. We estimated intestinal capacity by averaging Pgp activity along the intestine and multiplying by total small intestine mass. These first measures of Pgp in wild mammals show a significant difference among species with the juniper specialist, N. stephensi, exhibiting a 2.4 fold higher capacity than the generalist, N. albigula. This result suggests that Pgp may play a role in the ability of N. stephensi to tolerate juniper.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2006

Generalist genes and cognitive neuroscience.

Multivariate genetic research suggests that a single set of genes affects most cognitive abilities and disabilities. This finding already has far-reaching implications for cognitive neuroscience, and will become even more revealing when this - presumably large - set of generalist genes is identified. Similar to other complex disorders and dimensions, molecular genetic research on cognitive abilities and disabilities is adopting genome-wide association strategies. These strategies involve very large samples to detect DNA associations of small effect size using microarrays that simultaneously assess hundreds of thousands of DNA markers. When this set of generalist genes is identified, it can be used to provide solid footholds in the climb towards a systems-level understanding of how genetically driven brain processes work together to affect diverse cognitive abilities and disabilities.

Chromosome Mapping↗
PubMed2003

Reproductive response of generalist and specialist aphid morphs with the same genotype to plant secondary compounds and amino acids.

Many studies have paid particular attention to the role of either secondary plant compounds or amino acids as determinants of host-plant range in phytophagous insects. Here we examine the relative importance of both of these classes of compound in host acceptance by generalist and specialist morphs of the black bean aphid, Aphis fabae, that are morphologically similar and genetically identical. Eleven secondary plant compounds and six amino acids with known biological activity in aphids are presented to insects within an artificial membrane system as single compounds, mixtures of same-class compounds and combined mixtures of the two classes of compound. It is found that 1) when specific single secondary compounds and amino acids are presented to generalist and specialist morphs of A. fabae, differential responses are exclusively consistent with plant-use strategy for amino acids but not for secondary compounds, 2) neither secondary compound nor amino acid mixtures give reproductive responses entirely consistent with plant range, but the response to secondary compounds is broadly consistent with plant range whereas the response to amino acids is not, 3) when secondary compounds and amino acid mixtures are combined, the response to secondary compounds generally dominates that to amino acids. Some scenarios of plant-range determination by secondary plant compounds and amino acids, suggested by results, are discussed.

Amino Acids↗
PubMed2006

Gene expression and glucosinolate accumulation in Arabidopsis thaliana in response to generalist and specialist herbivores of different feeding guilds and the role of defense signaling pathways.

Glucosinolate accumulation and expression of glucosinolate biosynthetic genes were studied in response to four herbivores in Arabidopsis thaliana (L.) wild-type (Columbia) and mutant lines affected in defense signaling. Herbivory on wild-type plants led to increased aliphatic glucosinolate content for three of four herbivores tested, the aphid generalist Myzus persicae (Sulzer), the aphid specialist Brevicoryne brassicae (L.), and the lepidopteran generalist Spodoptera exigua Hübner. The lepidopteran specialist Pieris rapae L. did not alter aliphatic glucosinolate content in the wild-type, but indole glucosinolates increased slightly. Gene expression associated with aliphatic glucosinolate biosynthesis increased after feeding by all species, indicating that glucosinolate accumulation is not always regulated at the level of these gene transcripts. A. thaliana lines with mutations in jasmonate (coi1), salicylate (npr1), and ethylene signaling (etr1) diverged in gene expression, glucosinolate content, and insect performance compared to wild-type suggesting the involvement of all three modes of signaling in responses to herbivores. The coi1 mutant had much lower constitutive levels of aliphatic glucosinolates than wild-type but content increased in response to herbivory. In contrast, npr1 had higher constitutive levels of aliphatic glucosinolates and levels did not increase after feeding. Glucosinolate content of the etr1 mutant was comparable to wild-type and did not change with herbivory, except for P. rapae feeding which elicited elevated indolyl glucosinolate levels. Unlike the wild-type response, gene transcripts of aliphatic glucosinolate biosynthesis did not generally increase in the mutants. Both glucosinolate content and gene expression data indicate that salicylate and ethylene signaling repress some jasmonate-mediated responses to herbivory.

Animals↗
PubMed2000

Nestedness in assemblages of gyrodactylids (Monogenea: Gyrodactylidea) parasitising two species of cyprinid--with reference to generalists and specialists.

The structure of gyrodactylid assemblages in individual fishes of two species of cyprinid was determined. A total of 100 specimens of minnow, Phoxinus phoxinus, and 137 specimens of roach, Rutilus rutilus, were investigated for presence of gyrodactylids. Host specificity, specialists vs. generalists, was noted in each host fish. A nested pattern was recorded in parasite assemblages of minnow, the host with a dominant number of specialist gyrodactylids. A non-nested pattern was observed in parasite assemblages of roach, the host with a dominant number of generalist gyrodactylids. The host specificity appears to be a meaningful factor that determines the pattern of gyrodactylid assemblages of both fish hosts.

Animals↗
PubMed2002

A geometric analysis of nutrient regulation in the generalist caterpillar Spodoptera littoralis (Boisduval).

Nutritional regulatory responses of the generalist caterpillar Spodoptera littoralis (Boisduval) were explored, in choice and no-choice experiments, using the Geometric Framework. In the choice experiment, newly moulted final instar larvae were provided with one of three protein-biased foods (PB-food: p35:c7, p28:c5.6 or p21:c4.2) and one of three equal protein-carbohydrate ratio foods (ER-food: p21:c21, p16.8:c16.8 or p12.6:c12.6). On five of the nine treatments, caterpillars independently regulated protein and carbohydrate intake to a mixture of 57 and 43%, respectively. However, when the concentration of the ER-food decreased and that of the paired PB-food increased, caterpillars progressively abandoned regulation and ate more of the PB-food. Despite these regulatory differences, performance (survivorship, growth and development) was similar across all nine treatments. In the no-choice experiment, caterpillars were given one of five foods (p35:c7, p28:c14, p21:c21, p14:c28 and p7:c35). Results indicated that caterpillars moved to a point in protein-carbohydrate space that was consistent with the Equal Distance Rule of compromise, a pattern previously predicted for generalist feeders. The insects on the two extreme foods, p35:c7 and p7:c35, showed reduced pupal mass and longer development, respectively. There was also strong evidence for post-ingestive regulation of nutrient utilisation, notably for protein.

Journal Article↗
PubMed1996

The development of the generalist nurse within pre-registration nurse education in the UK: some points for consideration.

A major difference between pre-registration nurse education in the UK as distinct from most other European countries is the existence of discrete branches of nursing. The package of four specialty areas of adult nursing, children's nursing, learning disability, and mental health nursing do not exist at pre-registration level in the majority of other European countries. The Republic of Ireland offers pre-registration education in general, mental health and learning disability nursing, and not children's nursing. Intergovernmental support was given to the idea of a generalist nurse in 1988. Such a change in nurse education in the UK would have major implications for patients, nurses and the nursing profession, and requires careful consideration by all nurses in education and practice. This paper presents some of the key arguments for and against the adoption of a generalist approach to pre-registration nurse education in the UK.

Adult↗
PubMed1997

The coevolutionary potential of a 'generalist' parasite, the hen flea Ceratophyllus gallinae.

Hosts exert selection pressures on their parasites and it is often assumed that host-parasite coevolution with each host is less intense in a generalist parasite than for a parasite with a narrow host range. Selection pressure on the parasite, however, is rather determined by host specificity, i.e. the relative importance of each host, than simply by the range of hosts. The determination of host specificity requires an assessment of the prevalence and intensity of parasite infestation within each host's nests, as well as the local abundance of each host species. Since the hen flea, Ceratophyllus gallinae, is a rather generalist parasite of birds it could be concluded that there has been weak coevolution with each of its hosts. By reviewing the literature on the prevalence and intensity of hen flea infestations in bird nests we estimated the number of individuals produced in the nest of each host species. The comparative analysis shows (1) that the prevalence of infestation is highest in hole-nesting avian families, (2) that prevalence and intensity of infestation among bird families are highly correlated, and (3) that hole-nesting Paridae have the highest intensities of infestation and harbour the majority of the flea population. These results underline the fleas' potential for coevolution with Paridae despite their extensive host range.

Animals↗
PubMed2004

Elevated atmospheric CO(2) affects the chemical quality of brassica plants and the growth rate of the specialist, Plutella xylostella, but not the generalist, Spodoptera littoralis.

Cabbage, Brassica oleracea subsp. capitata (cv. Lennox and Rinda), and oilseed rape, Brassica rapa subsp. oleifera (cv. Valo and Tuli), plants were grown under ambient CO(2) (360 ppm) or elevated CO(2) (720 ppm) at 23/18 degrees C and under a photoperiod of 22/2 h light (250 micromol m(-)(2) s(-)(1))/dark regime for up to 5 weeks. Afterward, the performance of the crucifer specialist Plutella xylostella (Lepidoptera: Plutellidae) and the generalist Spodoptera littoralis (Lepidoptera: Noctuidae) on those plants was studied. The mean relative growth rate (RGR) of P. xylostella larvae, feeding on both cultivars of oilseed rape or on the Lennox cultivar of cabbage leaves grown at an elevated CO(2) concentration, was significantly reduced as compared to ambient CO(2). A negative larval growth rate at elevated CO(2) was observed for P. xylostella on both oilseed rape cultivars, but the growth rate was reduced but positive on cabbage. Conversely, the RGR of S. littoralis on either plant species was not affected by CO(2) treatment but was lower on cabbage cv. Rinda than on cv. Lennox. The mortality of the larvae was not affected by CO(2) treatment either. At the same time, elevated CO(2) significantly decreased the concentrations of leaf phytochemical constituents in oilseed rape, i.e., total phenolics and total nitrogen, but not in cabbage. The effect of elevated CO(2) on the leaf glucosinolate concentrations of both plant species was marginal. In addition, the observed significant changes in individual glucosinolate concentrations of oilseed rape leaves were not consistent among cultivars. However, our results demonstrate for the first time quite strong effects of CO(2) enrichment on the larval performance of P. xylostella, which is an important pest of Brassica plants around the world. Further studies are still required to increase our understanding of why elevated CO(2) differently affects the performance of specialist and generalist insect herbivores on Brassica plants.

Animals↗
PubMed2001

Differences in host use efficiency of larvae of a generalist moth, Operophtera brumata on three chemically divergent Salix species.

The food selection, growth, and fecundity of insect herbivores are largely dictated by the chemical composition and nutritive values of plant foliage. We studied the host-use efficiency of larvae of the generalist moth, Operophtera brumata (Lepidoptera: Geometridae) on three chemically divergent but nutritively similar willows (Salix spp.). The 4th instars were able to use the salicylate-free leaves of S. phylicifolia efficiently. Growth was slightly reduced on S. pentandra, which contained a moderate level of acetylated salicylates. The high concentration of salicylates found in the leaves of S. myrsinifolia seemed to provide efficient protection against non-specialized O. brumata. We also studied assimilation of nutrients and degradation of salicylates and other secondary compounds in the digestive tract of O. brumata larvae. Neither the assimilation of nitrogen nor of carbon were affected by secondary chemicals of ingested food. Salicylates were shown to be degraded to salicin and catechol, while further degradation of salicin to saligenin was rather slow. In an artificial diet experiment, we showed that two degradation products of salicylates, catechol and saligenin markedly reduced the growth of the larvae. Neither salicin nor chlorogenic acid affected larval growth. We conclude that salicylates reduced the growth of the generalist winter moth mainly by feeding deterrence caused by 6-hydroxy-2-cyclohexenone and catechol. Compared to the deleterious effects of salicylates the effects of other secondary compounds were minor.

Animals↗
PubMed2001

Australian hospital generalist and critical care nurses' perceptions of doctor-nurse collaboration.

Previous researchers have indicated that collaborative practice between doctors and nurses results in positive effects on patient care, health-care costs and provider satisfaction. Despite these benefits, collaborative practice appears to be the exception, rather than the dominant pattern, within health care. A collaborative relationship cannot evolve if individuals do not value and respect others' competencies. This study, a mailed survey, used the Collaboration with Medical Staff Scale to compare the perceptions of doctor-nurse collaboration held by critical care nurses and generalist hospital nurses. The hypothesis that critical care nurses perceive there to be greater collaboration with doctors than their generalist nurse colleagues was supported even after taking into consideration education and experience. These results suggest that critical care is an area that might be useful when trying to understand the dimensions and implications of collaboration among health professionals.

Adult↗
PubMed2005

[Thyroid surgery: generalist or specialist?].

BACKGROUND: Thyroid surgery is done in Germany in a considerable numbers of operations (about 110,000 per year). To perform thyroid operations by so called "generalists" or "specialists" have been discussed intensively, however, this issue have not been analyzed in detail. METHODS: Study material comprised 16,500 consecutive thyroid operations with 30,000 operated sites that have been prospectively documented in the German Thyroid Multicenter Study performed 1998 through 2001. Quality of surgery were analyzed by calculating the inverse relationship between volume and outcome (complication rate). RESULTS: To achieve complication rates (permanent unilateral recurrent laryngeal nerve paralysis and hypocalcemia) of < 1 % (primary surgery) or < 3 % (redo surgery) the minimum number of thyroid operations of lower level of experience (e. g. benign nodular goiter) per year was n=30. The minimum number of operations with higher level of experience was significantly lower (n=3-12) due to the higher level of experience of operating surgeons. In contrast to the rates of postoperative hypocalcemia the rates of postoperative recurrent laryngeal nerve paralysis was clearly related to the number of thyroid operations performed. CONCLUSIONS: The high number of thyroid operations in Germany with about 20 % of operations of high level experience are requiring surgical curricula and hospital structures that offer as well generalists as specialists to treat the broad spectrum of thyroid diseases accordingly. To lower the complication rate especially of difficult thyroid operations the level of specialization in Germany have to be increased.

Clinical Competence↗
PubMed1994

Redesigning the surgical teaching of fourth-year medical students to meet the training needs of generalists.

The fourth year of the medical student curriculum remains of questionable educational value at most medical schools. The training needs of generalists include the acquisition of knowledge and skills in broad areas of general surgery and the surgical subspecialties. By appropriately tailoring the educational objectives to the learning needs of individual students and implementing teaching models based on principles of adult education, a special surgical experience may be provided to each fourth-year medical student, building on the previously acquired knowledge and skills. Rotations may be offered in a number of surgical disciplines, with heavy emphasis on teaching in the ambulatory setting. One such model was recently implemented at The Medical College of Pennsylvania. Advantages of this type of program include support of the training of generalists using contemporary teaching strategies and provision of a meaningful educational experience to medical students during the fourth year.

Ambulatory Surgical Procedures↗
PubMed2005

Opportunities and challenges to improving end-of-life care for seriously ill elderly patients: a qualitative study of generalist physicians.

BACKGROUND: End-of-life care quality deficiencies have in part been linked to inadequate physician skill in the technical and communication domains of palliative care. Yet few studies have examined physicians' perspectives regarding their experiences caring for patients approaching the end of life. OBJECTIVE: To understand generalist physicians' perspectives regarding their care of seriously ill elderly patients in order to identify challenges to improving end-of-life communication and decision-making. DESIGN: Qualitative study using in-depth ethnographic interviews. SETTING: Puget Sound region of Washington State. PARTICIPANTS: Thirteen community-based generalist physicians who routinely care for elderly patients and represent a range of practice styles and experiences. RESULTS: The physicians described a "revolving door syndrome" in which elderly patients are repeatedly hospitalized with chronic illness exacerbations. Three themes influenced physicians' interactions with "revolving door" patients: (1) physicians' use of decision-making heuristics, characterized as "internal gauges," to promote care consistent with their own values; (2) families' "unreasonable expectations" that patients would return to their previous health after treatment of an acute illness; and (3) families' reluctance to accept end-of-life decision-making responsibility. CONCLUSIONS: Our findings suggest that physician values and physician-family interactions impact decision-making for chronically ill elderly patients. The influence of physicians' internal gauges on end-of-life care can facilitate or hinder use of palliative care as well as decision-making consistent with patients' preferences. Disparate physician and family expectations regarding their division of decision-making responsibility and patients' care outcomes may also affect decision-making. The use of communication strategies that promote alignment of these expectations may improve decision-making quality for incapacitated elderly patients.

Adult↗
PubMed1996

Family practice, internal medicine, and pediatrics as partners in the education of generalists.

The generalist of the future will play an integral role in the health care delivery system, yet the three recognized generalist specialties have developed and functioned along largely separate tracks. No matter what form of generalism evolves, family practice, internal medicine, and pediatrics must begin to cooperate and collaborate in developing new graduate medical education programs that are sufficiently flexible to meet whatever emerges in the future. They must devote their energies to working together, rather than competing; to emphasizing those parts of their programs that have similarities; and to sharing their knowledge, skills, attitudes, and perspectives about the care of patients. They must develop training experiences in which residents will obtain maximum contact with a wide variety of problems and patients in many different settings; a substantial portion of such training should be generic and virtually interchangeable among the three specialties. As the health care system evolves, so should these disciplines; they must begin to "train physicians to provide continuing, comprehensive and coordinated medical care to a population undifferentiated by gender, disease or organ system," as urged by the American Boards of Family Practice and Internal Medicine.

Education, Medical, Graduate↗
PubMed1999

The role of the generalist physician initiative in the merger of Hahnemann University and Medical College of Pennsylvania.

Unique in the history of academic medicine in the 20th century was the 1993 merger of two medical schools, Hahnemann University and The Medical College of Pennsylvania, to create Allegheny University of the Health Sciences, the largest private medical school in the United States. During the early, most critical phase of the merger process, the two faculties were brought together to plan and submit an application for The Robert Wood Johnson Foundation's Generalist Physician Initiative (GPI). This action had a profound and lasting impact on the merger of the two schools and the educational enterprise that subsequently evolved. The GPI grant was awarded to the merged school in the midst of this complex merger rife with major changes, all with their attendant fears and frustrations. During and just after the merger, at a time when faculty and staff were somewhat uncertain about the direction of the university, the GPI provided a focus with a clear set of goals and objectives. Despite the unprecedented changes occurring in the organization and personal and professional concerns, faculties from the two institutions were able to join in pursuing the generalist initiative and its associated curriculum reform. This single, pervasive effort was a significant factor in forming a unified faculty of a united school of medicine. This sense of unity was put to the test when, in July 1998 the university, along with its affiliated hospital system, filed for bankruptcy. The goals of this extraordinary action were to sell the hospitals to another organization, thereby removing from the university the burden of supporting hospital-based clinical programs and allowing the university to emerge as a freestanding academic institution focusing on its core mission of education and the principles embodied in the GPI.

Curriculum↗
PubMed1999

Recruiting and selecting generalist-oriented students at Pennsylvania State University College of Medicine.

The authors describe the strategies developed at the Pennsylvania State University College of Medicine, as part of The Robert Wood Johnson Foundation's Generalist Physician Initiative, to increase the proportion of graduating medical students entering generalist disciplines. These strategies included modifying the admission process to involve more primary care faculty so that students with identified potential for primary care would make up at least half of each entering class, and partnering with selected colleges and universities in Pennsylvania to increase the number of applicants with the potential for primary care. They describe partnering and outreach programs--Primary Care Day, off-campus cluster meetings, and the Primary Care Scholars Program for college seniors--and present promising information about the results.

Education, Medical, Undergraduate↗
PubMed2001

What did we learn about leadership in medical education? Effecting institutional change through the Interdisciplinary Generalist Curriculum Project.

The Interdisciplinary Generalist Curriculum (IGC) Project required significant collaboration and cooperation at many levels of leadership to accommodate early clinical experiences in the curriculum. Three elements of institutional change are discussed: the context for desired early clinical experiences in medical education, structural elements required of the IGC Project schools, and leadership within the demonstration schools. Lessons learned from these interdisciplinary projects include the importance of supportive leadership from the top levels, establishing broad buy-in across sectors of the school, creating a team administrative structure that fosters participation by all groups, and central (rather than departmental) administration. The processes needed to establish collaborative leadership and full participation by the generalist departments and cooperation of diverse constituencies, such as basic science faculty, were labor-intensive and required more time to ensure successful program implementation. Uniformly, strong support at the highest levels of the organization, especially the medical schools' deans, was cited as a key element in the success of the IGC Project. An interesting unanticipated outcome of the project was the movement of the interdisciplinary course administration into a central location (dean's office) by the end of the project for all schools. This change may reflect a practical advantage for administration of interdisciplinary programs located at the level of the school or college, rather than housed within departments.

Administrative Personnel↗