New bacterial species associated with chronic periodontitis.

Recent investigations of the human subgingival oral flora based on ribosomal 16S cloning and sequencing have shown many of the bacterial species present to be novel species or phylotypes. The purpose of the present investigation was to identify potential periodontal pathogens among these newly identified species and phylotypes. Species-specific ribosomal 16S primers for PCR amplification were developed for detection of new species. Associations with chronic periodontitis were observed for several new species or phylotypes, including uncultivated clones D084 and BH017 from the Deferribacteres phylum, AU126 from the Bacteroidetes phylum, Megasphaera clone BB166, clone X112 from the OP11 phylum, and clone I025 from the TM7 phylum, and the named species Eubacterium saphenum, Porphyromonas endodontalis, Prevotella denticola, and Cryptobacterium curtum. Species or phylotypes more prevalent in periodontal health included two uncultivated phylotypes, clone W090 from the Deferribacteres phylum and clone BU063 from the Bacteroidetes, and named species Atopobium rimae and Atopobium parvulum.

ATP stimulates human macrophages to kill intracellular virulent Mycobacterium tuberculosis via calcium-dependent phagosome-lysosome fusion.

Advances in therapy for tuberculosis will require greater understanding of the molecular mechanisms of pathogenesis and the human immune response in this disease. Exposure of Mycobacterium tuberculosis-infected human macrophages to extracellular ATP (ATP(e)) results in bacterial killing, but the molecular mechanisms remain incompletely characterized. In this study, we demonstrate that ATP(e)-induced bactericidal activity toward virulent M. tuberculosis requires an increase in cytosolic Ca(2+) in infected macrophages. Based on our previous work with primary infection of human macrophages, we hypothesized that the Ca(2+) dependence of ATP-induced killing of intracellular M. tuberculosis was linked to promotion of phagosome-lysosome fusion. Using confocal laser-scanning microscopy, we demonstrate that ATP(e) induces fusion of the M. tuberculosis-containing phagosome with lysosomes, defined by accumulation of three lysosomal proteins and an acidophilic dye. Stimulation of phagosome-lysosome fusion by ATP(e) exhibited distinct requirements for both Ca(2+) and phospholipase D and was highly correlated with killing of intracellular bacilli. Thus, key signal transduction pathways are conserved between two distinct models of human macrophage antituberculous activity: primary infection of naive macrophages and physiologic stimulation of macrophages stably infected with M. tuberculosis.

Inhibition of human platelet function by sulfatides.

Sulfatides are glycolipid constituents of human platelet cell membranes and have been shown to interact with platelet-binding proteins involved in hemostasis. Because little is known about the physiological role of sulfatides in platelet function, the effect of sulfatide on platelet adhesion, aggregation, release, and ristocetin-induced platelet agglutination (RIPA) was studied. These processes are inhibited when exogenous sulfatide is present in vitro. Inhibition of aggregation induced by collagen, thrombin, and ristocetin by sulfatide was dose dependent. Adenosine diphosphate-mediated adhesion and aggregation were not significantly affected by sulfatide, nor was serotonin- and epinephrine-mediated aggregation. Collagen mediate release of serotonin was reduced sulfatide. RIPA demonstrated dose-dependent inhibition in response to sulfatide. These results suggest that sulfatide may play a role in modulating platelet activation.

Haemofiltration: how to do it.

Haemofiltration and its variants are simple procedures which allow the management of patients with renal failure in intensive therapy units without the need for continual support from renal specialists. In order for non-renal specialists to manage the practical aspects of these treatments logically, safely and successfully it is important to understand the basic principles involved.

Home visitation to migrant farm worker families: an application of Zerwekh's family caregiving model for public health nursing.

Zerwekh's family caregiving model incorporates holistic care concepts as intervention strategies for vulnerable families. It is a model that can be taught to nurses when the practice arena involves family care. The article describes the use of Zerwekh's family caregiving competencies by novice nurses (ie, 13 final semester nursing students) in their home visits to migrant farm worker families. A qualitative analysis of data derived through written narratives focuses on Zerwekh's three basic competencies of locating families, building trust, and building strength and on the encompassing competencies of timing and detecting.

Evaluation study of a transcultural discovery learning model.

This qualitative, descriptive study explored the extent to which students' discovery learning centered around cultural understanding and sensitivity occurs in a clinical rotation involving migrant health care. Thirteen nursing students enrolled in this community health clinical rotation were the study sample. Demographically, they were similar to other baccalaureate students in the school of nursing. Characteristics that set them apart were their levels of maturity, motivation, and independence, and their ability to cope with stress and ambiguity. Student journal entries were used to explore changes in cultural understanding and sensitivity over the course of an intensive six-week clinical experience. The method of inquiry was qualitative descriptive. Discovery learning from the perspective of the students was analyzed using domain analysis scheme. Themes that emerged from analysis of the data were personal and professional growth, specialized nursing practice roles with ethnic minorities, and health care system needs and issues for culturally sensitive care. Our findings contribute to faculty understanding of the degree to which student nurses make a transformation in terms of cultural understanding and sensitivity, and the process by which increased cultural understanding and sensitivity result in application of theoretical transcultural concepts.

A collaborative effort between a state migrant health program and a baccalaureate nursing program.

This article reports on the way in which a unique collaborative effort between a service agency and a baccalaureate nursing program grew out of the needs of the two separate agencies. The first agency, the Colorado Migrant Health Program, was faced with a budget that was inadequate to meet the health-care needs of the migrant population. The second, a baccalaureate nursing program at the University of Colorado, was finding it increasingly difficult to locate appropriate generalized community health clinical placements with an opportunity for student discovery learning related to transcultural health care. Discussions of a collaborative effort ensued and it became evident that each had something to gain from such an effort. Now, after almost 10 years of cooperation, the commitment to the endeavor on the part of both agencies remains strong as the benefits to each continue to increase. The ultimate beneficiaries, however, are the migrant families receiving care and the students providing care. The way in which the program has evolved over time, a description of the current program, and a discussion of the resources that help to maintain the program are presented. In addition, the curriculum course design, and teaching strategy modifications necessary to facilitate the collaborative program are discussed.

Technologic enrichment of a community needs assessment.

In this article, we have reported the implementation and evaluation of a project to improve the community needs assessment process and product through technologic enhancement. Our description of the method reveals our heavy emphasis on the ethnographic approach in this model of community analysis. An Academic Enrichment Grant provided the two of us, community health nursing faculty members, funding to purchase tape recorders, a transcriber, a laptop computer, and a printer to facilitate the needs assessment. We evaluated the project in terms of accuracy, enhanced analysis, ease and efficiency, and student learning of ethnographic methods. The project did improve accuracy and enhanced the analysis. Although it improved ease of data collection, organization, and presentation, it did not produce a savings in time. It did facilitate student learning of ethnographic interviewing and analysis. Recommendations included expanding the use of technology, increasing training and student responsibility, and expanding the actual needs assessment to a two-semester project.

Predictors of outcome in children hospitalized with maxillofacial infections: a linear logistic model.

The purpose of this study was to determine factors predictive of clinical outcome for pediatric patients with maxillofacial infections. Using linear logistic regression, four important variables, age, admission temperature, admission white blood cell count, and source of infection, were identified. Relevant study variables were abstracted from the records of all children less than 15 years old admitted to San Francisco General Hospital (SFGH) with facial infections between 1982 and 1986 (n = 105). An unfavorable clinical outcome was defined as a length of hospital stay (LOS) greater than or equal to 4 days and/or the need for an operation to resolve the infection. A favorable outcome was a LOS less than 4 days and no operation. To develop and validate the linear logistic model, the original group of patients (n = 105) was divided into index and validation sets. The index set was created by randomly selecting 80 of the original patients. The model was then applied to a validation set of the 25 remaining children. The model predicted that 13.95 of the patients in the validation set would have an unfavorable outcome. The actual number of unfavorable outcomes was 16. To further test the model's validity, a third data set was collected. It was composed of pediatric patients admitted to SFGH between January 1, 1987 and June 30, 1989 (n = 24). The model predicted that 15.99 of these patients would have an unfavorable outcome; 17 patients actually did have an unfavorable outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

Parental adaptation to adolescent drug abuse: an ethnographic study of role formulation in response to courtesy stigma.

Community based nurses have increasingly been involved in caring for the parents of drug abusing adolescents. They are in need of research data about how parents are coping with the problem. This study analyzed parental role formulation in response to their position as parents of deviant children. The method of inquiry was ethnographic. Data were gathered from nonparticipant observations, parent informant journals, and interviews with parents involved in a survival group. Parents move through three phases of role formation, the content of which has implications for nursing assessments. The similarities of these parents to those of physically and mentally handicapped children is striking. Both are outside the conventional norm and are constantly involved in interpreting situations with others as to their different parenting role. A pecularity in the findings is that the parents were less discredited by their family and friends than had been anticipated. They met their greatest discreditation from community institutions, including the school, police, and court systems, institutions that were expected to assist them in bringing their child's drug abuse under control.

Reinforced polycarboxylate cements.

Mechanical properties of polycarboxylate cements are greatly improved by incorporation of high modulus fibers such as potassium titanate into acrylic-itaconic acid and acrylic-itaconic-acronitic acid copolymers. Other desirable properties of the cements are not changed by the addition of fibers.