Immersing undergraduates into an interprofessional longitudinal rural placement.

INTRODUCTION: An Integrated Multidisciplinary Model of Education in Rural Settings (IMMERSe) program was piloted in 2010 in a rural region of South Australia. The aim of the program was to place students from different health programs together, in a rural environment, for one or two semesters of the academic year to promote interprofessional learning. Students were given the opportunity to participate in joint fortnightly education sessions with an emphasis on interprofessional relations and teamwork, undertaking activities such as case studies, role plays, journal club, work shadowing and invited speakers. METHODS: A qualitative approach was used to explore student perspectives of a rural interprofessional clinical placement. Students were invited to participate in focus groups and reflective writing exercises. This data was analysed in relation to the students' thoughts and reflections around professionalism, teamwork and collegial relationships. RESULTS: The analysis resulted in three major themes: (1) interprofessional interactions with other students; (2) interprofessional interactions with other health professionals; and (3) interprofessional interactions with the community. Students in our study demonstrated a new level of respect for health professionals outside of their discipline, and gained a sense of how their own independent roles can blend or partner with others' roles, to draw on each other's expertise. CONCLUSIONS: Student learning experiences can be enhanced through engagement and integration in a rural community context. Interprofessional learning in a rural community placement can increase students' understanding of professionalism, teamwork and collegiality, which are all important components of collaborative practice. Reflective journaling is a useful method for evaluating the student experience.

Pilot evaluation of anterior dynamic ultrasound screening for developmental dysplasia of the hip in an Australian regional hospital.

INTRODUCTION: Developmental Dysplasia of the Hip (DDH) is the most common notifiable musculoskeletal birth defect in South Australia (SA). Despite routine screening by physical examination of the hips in the neonatal period and at 6 weeks of age, the risk of late diagnosis is increased in rural areas. It is assumed this is due to the examining doctors' reduced clinical expertise. Introducing Anterior Dynamic Ultrasound (ADUS) has reduced the late detection rates in Sweden to almost zero, and may benefit Australian infants in rural areas if routine screening was introduced. This study reports on a small implementation pilot in a SA regional hospital where volunteer postnatal mothers consented to their babies having ADUS examinations. METHODS: The pilot was evaluated by collecting results of physical examination, ADUS, and surveying parental impressions of the screening test. RESULTS: Hips of 86 infants underwent ADUS during the implementation pilot. Parents' perceptions were mainly very positive and indicated ADUS was an accessible and acceptable screening test. Of the hips scanned, three were found to have maximum movement of the femoral head of >3 mm and were deemed to demonstrate increased laxity. Four hips described as loose or mobile on clinical examination were found to be within normal limits of maximum mobility on ADUS. CONCLUSIONS: This study has demonstrated that a larger scale implementation project would be feasible in regional Australia, and would enable researchers to better understand how to reduce the late diagnosis rate of DDH in rural areas.

A scalable cryogenic LED module for selectively illuminating kinetic inductance detector arrays.

We present the design and measured performance of a light emitting diode (LED) module for spatially mapping kinetic inductance detector (KID) arrays in the laboratory. Our novel approach uses a multiplexing scheme that only requires seven wires to control 480 red LEDs, and the number of LEDs can be scaled up without adding any additional wires. This multiplexing approach relies on active surface mount components that can operate at cryogenic temperatures down to 10 K. Cryogenic tests in liquid nitrogen and inside our cryostat demonstrate that the multiplexer circuit works at 77 and 10 K, respectively. The LED module presented here is tailored for our millimeter-wave detector modules, but the approach could be adapted for use with other KID-based detector systems.

Food availability and sex reversal in Mytella charruana, an introduced bivalve in the southeastern United States.

We studied the reproductive biology of Mytella charruana to determine the potential reproductive success of this newly introduced bivalve species from Central/South America. We analyzed gonad morphology, gametogenesis, and the sex ratios of introduced populations throughout a 12 month period. In the non-native habitat M. charruana shows the same strategy of gametogenesis that had been observed in its native environment, which is an opportunistic type of gonadal cycle with gametes produced throughout the year. Instead, the spawning period of M. charruana along the southeastern US coast is extended compared to that found in the native environment. We determined the minimum size (shell length) of sexually reproductive mussels to be 1.25 cm. Interestingly, throughout the year the population samples were typically composed of a higher proportion of females. The female to male sex ratio varied within a wide range from 1:0 to 1:3.3. Upon this discovery we tested the effects of food availability on the gametogenesis of adult animals. The sex ratio of mussels collected from different locations and maintained in the laboratory with or without food changed toward a male-bias under starvation conditions within a month. This is the first study directly showing that food availability can trigger sex reversal in an adult bivalve. According to our data this mussel species will likely continue to spread along the east coast of the US. Moreover, M. charruana may prove to be a model organism in the study of alternative sexuality in bivalves.

Precursors of chondroitin sulfate proteoglycan are segregated within a subcompartment of the chondrocyte endoplasmic reticulum.

Immunocytochemical methods were used at the levels of light and electron microscopy to examine the intracellular compartments of chondrocytes involved in extracellular matrix biosynthesis. The results of our studies provide morphological evidence for the compartmentalization of secretory proteins in the ER. Precursors of the large chondroitin sulfate proteoglycan (CSPG), the major proteoglycan species produced by chondrocytes, were present in the Golgi complex. In addition, CSPG precursors were localized in specialized regions of the ER. Link protein, a separate gene product which functions to stabilize extracellular aggregates of CSPG monomers with hyaluronic acid, was segregated similarly. In contrast, type II procollagen, another major secretory molecule produced by chondrocytes, was found homogeneously distributed throughout the ER. The CSPG precursor-containing ER compartment exhibits a variable tubulo-vesicular morphology but is invariably recognized as an electronlucent, smooth membrane-bounded region continuous with typical ribosome-studded elements of the rough ER. The observation that this ER structure does not stain with antibodies against resident ER proteins also suggests that the compartment is a specialized region distinct from the main part of the ER. These results support recent studies that consider the ER as a compartmentalized organelle and are discussed in light of the possible implications for proteoglycan biosynthesis and processing.

Ethical issues in the prevention and treatment of HIV infection and AIDS.

The epidemic of infection with the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome (AIDS) poses a major ethical question: How can we control the epidemic and the harm that it causes without unjustly discriminating against particular social groups and without unnecessarily infringing on the freedom of individuals? This question pertains to three spheres of public policy in the United States: public health, the delivery of health care, and research. In the public health sphere, vigorous educational efforts will be required, as will modified approaches to intravenous drug use, prostitution, and homosexual and bisexual sexual activity. Carefully targeted, voluntary testing and screening programs should be coupled with counseling and with guarantees of confidentiality and nondiscrimination where these are appropriate. Both health care workers and the health care system have a moral obligation to provide care to people with HIV infection, but heroic self-sacrifice should not be required provided that infection control precautions are observed. Patients with neurological involvement and terminally ill patients will benefit from statutes allowing recognition of advance directives about preferred modes of care or nontreatment. There is a moral imperative to perform intensive research directed toward the understanding, treatment, and prevention of HIV infection and AIDS. The research process will raise challenging ethical questions.

Germ-line gene modification and disease prevention: some medical and ethical perspectives.

There has been considerable debate about the ethics of human germ-line gene modification. As a result of recent advances in the micromanipulation of embryos and the laboratory development of transgenic mice, a lively discussion has begun concerning both the technical feasibility and the ethical acceptability of human germ-line modification for the prevention of serious disease. This article summarizes some of the recent research on germ-line gene modification in animal models. Certain monogenic deficiency diseases that ultimately might be candidates for correction by germ-line intervention are identified. Several of the most frequently considered ethical issues relative to human germ-line gene modification are considered in the context of professional ethics, parental responsibility, and public policy. Finally, it is suggested that there is merit in continuing the discussion about human germ-line intervention, so that this technique can be carefully compared with alternative strategies for preventing genetic disease.

New goals for the U.S. Human Genome Project: 1998-2003.

The Human Genome Project has successfully completed all the major goals in its current 5-year plan, covering the period 1993-98. A new plan, for 1998-2003, is presented, in which human DNA sequencing will be the major emphasis. An ambitious schedule has been set to complete the full sequence by the end of 2003, 2 years ahead of previous projections. In the course of completing the sequence, a "working draft" of the human sequence will be produced by the end of 2001. The plan also includes goals for sequencing technology development; for studying human genome sequence variation; for developing technology for functional genomics; for completing the sequence of Caenorhabditis elegans and Drosophila melanogaster and starting the mouse genome; for studying the ethical, legal, and social implications of genome research; for bioinformatics and computational studies; and for training of genome scientists.

Peptide and protein synthesis by segment synthesis-condensation.

The chemical synthesis of biologically active peptides and polypeptides can be achieved by using a convergent strategy of condensing protected peptide segments to form the desired molecule. An oxime support increases the ease with which intermediate protected peptides can be synthesized and makes this approach useful for the synthesis of peptides in which secondary structural elements have been redesigned. The extension of these methods to large peptides and proteins, for which folding of secondary structures into functional tertiary structures is critical, is discussed. Models of apolipoproteins, the homeo domain from the developmental protein encoded by the Antennapedia gene of Drosophila, a part of the Cro repressor, and the enzyme ribonuclease T1 and a structural analog have been synthesized with this method.

Expression of receptor tyrosine kinase targets PDGFR-ß, VEGFR2 and KIT in canine transitional cell carcinoma.

Transitional cell carcinoma (TCC) is the most common neoplasia of the canine urinary tract. It tends to be locally invasive and has a moderate metastatic rate. Receptor tyrosine kinases (RTKs) play an important role in promoting cell growth, differentiation and regulation of cell function. RTK inhibitor toceranib phosphate has been used anecdotally to treat TCC. The goal of this study was to evaluate archived normal urinary bladder, TCC and cystitis bladder samples for expression of toceranib phosphate targets: VEGFR2, PDGFR-ß and stem cell factor receptor (KIT). A significant number of TCC samples expressed PDGFR-ß compared with cystitis and normal bladder samples (P<.0001). While all the tumour samples stained positively for VEGFR2, there was no significant difference between tumour, cystitis and normal bladder samples in intensity scores or staining distribution. Minimal positive staining for KIT was noted in the tumour samples. Based on this proof of target study, further investigation is warranted to determine clinical response of TCC to toceranib phosphate.

Measurement of Campylobacter numbers on carcasses in British poultry slaughterhouses.

An assessment of the proposed new International Organization for Standardization quantitative method for Campylobacter was undertaken on poultry carcass samples collected after the chilling phase of processing. Using a critical differences method, we determined the uncertainty associated with log-transformed Campylobacter numbers by dual analyses of 346 samples collected from 22 processing plants located throughout the United Kingdom. Overall, using log-transformed Campylobacter numbers that ranged between -1 and 5 log, we calculated the expanded measurement of uncertainty (EMU) to be 3.889 for the new method. The EMU changed when ranges of bacterial numbers were grouped for analyses. For low numbers of Campylobacter (< 1 log), the EMU was calculated to be 5.622. There was less measurement error with higher bacterial numbers because the EMU was found to be 0.612 for samples containing Campylobacter numbers of 3 log or above. The draft method was used to measure numbers of Campylobacters on poultry carcasses collected from 18 United Kingdom processing plants in summer and winter. Numbers were significantly lower in winter. We conclude that, although the new method is adequate at quantifying high numbers of Campylobacter on poultry carcasses, further development is required to improve the measurement of small numbers of this causative agent of foodborne illness.

An assessment of sampling methods and microbiological hygiene indicators for process verification in poultry slaughterhouses.

Studies to determine the appropriateness of the use of populations of indicator bacteria on poultry carcasses for process verification were undertaken in commercial slaughterhouses. Samples were collected from neck skin by excision or from whole carcass rinses and were examined for a range of presumptive process hygiene indicator bacteria. Coefficients of variation were calculated for each bacterial indicator and were significantly lower in excised samples, indicating more reproducible bacterial recovery by this sampling method. Total viable counts of aerobic bacteria, Enterobacteriaceae, and Pseudomonas in samples collected by excision had the lowest coefficients of variation when compared with other indicators and were therefore used for further study. The uncertainties associated with the quantification of each bacterial indicator were calculated and were lowest overall for total viable counts of aerobic bacteria. In general, uncertainty was higher for lower bacterial numbers. Results of microbiological testing on pooled excised neck skin samples were not significantly different from the mean of individually analyzed samples. Bacterial numbers increased by 1 log unit when cultures were stored under chilled conditions typical of those used for transporting samples to external laboratories, but the increases were not significant for Pseudomonas and aerobic bacteria when storage time was less than 17 h. Weak relationships were identified between bacterial indicator numbers and duration of processing, although cleanliness of the processing environment diminished visibly during this time. In the plants visited for this study, there was a poor relationship between presumptive bacterial indicator numbers and process hygiene. Consequently, bacterial analyses for process verification purposes may be of limited value.

The impact of medical students on rural general practitioner perceptors.

INTRODUCTION: As universities rely more heavily on rural GPs to precept medical students, the formation of symbiotic partnerships benefiting students, universities and GPs, becomes imperative. In order to develop and consolidate these partnerships Universities must understand who their rural GP preceptors are and how precepting impacts on them. METHODS: A review of the literature was undertaken to determine the significant themes of student impacts from articles where conclusions were clearly based on empirical findings. RESULTS: Forty-three articles were included in the final review, but only nine specifically looked at impacts on rural GPs. Impacts were categorised into six domains: personal; time; patient care; professional relationships and professional development; business and infrastructure; and recognition and remuneration. CONCLUSIONS: Literature specifically addressing the impact of precepting on rural GPs is scarce. Further studies are required to evaluate the relationship between the quality of teaching delivered to students, the type and length of student attachments and the likely impacts on rural GPs.

Quality control of bone densitometry in a national health survey (NHANES III) using three mobile examination centers.

A quality control (QC) program for bone mineral measurements at the proximal femur by dual-energy x-ray absorptiometry (DXA) was designed for the osteoporosis component of the Third National Health and Nutrition Examination Survey (NHANES III). Major elements of the QC program are (1) a QC center for review of all scans, (2) setup procedures for and continuous monitoring of daily QC procedures, (3) reference standards for cross-calibration, (4) longitudinal studies for assessment of instrument stability, (5) monitoring of technologist performance, and (6) training. This report describes the results of the QC program of the first half of this 6 year study, which began in 1988. Measurements were performed on 7376 subjects in three mobile examination centers, which traveled to a new location about every 3 months, a total of 44 locations. A small percentage (3.5%) of all scans were rejected, mostly because of patient motion during scanning, but 33% of the remaining scans required reanalysis at the QC center to refine the location of the regions of interest. Precision in spine and hip phantoms was below 1% at all ROIs. In 535 subjects with duplicate scans, age 20-91 of both sexes, examined in a blinded review, precision for BMD at the femur neck ROI was 3.2% (CV) and 5.1% for Ward's triangle BMD. The central review improved scan quality, increased the number of usable scans, and reduced significantly the range of the mean percentage difference in the duplicate scans. Minor alterations in machine function were observed and corrected. QC results on phantoms were similar to those obtained with stationary instruments in dedicated laboratories. Retrospective analysis of the regression slopes from QC records did not show a need for correction of the data base, indicating that the instruments were stable during the course of the study.

Human gene therapy: ethics and public policy.

The first three human gene transfer/therapy clinical protocols are now underway after having been subjected to an extensive review process by the Recombinant DNA Advisory Committee (RAC) and its Human Gene Therapy Subcommittee. The "Points to Consider" document developed by the RAC established the framework for evaluating genetic intervention protocols. This review process is taking place in a broader social context. Public attitude surveys in this country have indicated a general lack of knowledge in the area of genetic engineering but an acceptance of somatic-cell gene therapy as treatment for disease. Internationally, numerous policy statements on human genetic intervention have been published, all of which support the moral legitimacy of somatic-cell gene therapy for the cure of disease. The debate over the ethical issues related to somatic-cell gene therapy has evolved over a ten-year-period. The time has now come to begin a formal public process for the ethical assessment of germ-line genetic intervention.

Tartrate-resistant acid phosphatase in bone and cartilage following decalcification and cold-embedding in plastic.

Tartrate-resistant acid phosphatase (TRAP) has been proposed as a cytochemical marker for osteoclasts. We have developed an improved technique for the localization of TRAP in rat and mouse bone and cartilage. This procedure employs JB-4 plastic as the embedding medium, permits decalcification, and results in improved morphology compared with frozen sections. Peritoneal lavage cells were used to determine the appropriate isomer and concentration of tartrate necessary for inhibition of tartrate-sensitive acid phosphatase. After incubation in medium containing 50 mM L(+)-tartaric acid, osteoclasts and chondroclasts were heavily stained with reaction product. On the basis of their relative sensitivity to tartrate inhibition, three populations of mononuclear cells could also be distinguished. These three populations may represent: heavily stained osteoclast/chondroclast precursors; sparsely stained osteoblast-like cells lining the bone surface; and unstained cells of monocyte-macrophage lineage. Our results are consistent with the use of TRAP as a histochemical marker for study of the osteoclast.

Host-parasite relationship of Leishmania mexicana mexicana and Lutzomyia abonnenci (Diptera: Psychodidae).

The life cycle of Leishmania mexicana mexicana in the gut of the sand fly, Lutzomyia abonnenci, was studied by light and electron microscopy. Development was suprapylarian with initial establishment of parasites in the bloodmeal (posterior midgut), and anterior migration of parasites to the cardia/stomodeal valve region beginning at 2.5 days post-infection. Flagellates were first observed in the esophagus at 3.5 days, in the posterior armature region of the pharynx at 5 days, and in the anterior pharynx at 7 days; but they were not detected in the cibarium or proboscis. Infection of the pylorus region of the hindgut and of the Malpighian tubules was also commonly observed. Three different morphological forms of L. m. mexicana developed in the gut: nectomonad promastigotes, short promastigotes, and paramastigotes. Nectomonads occurred primarily in the abdominal midgut after bloodmeal digestion, where they were oriented in longitudinal masses in the lumen, or interdigitated with epithelial microvilli via the flagellum. Short promastigotes found in the cardia/stomodeal valve region are described for the first time. These forms were smaller than nectomonads, showed an amplification of the kinetoplast, apposition of kinetoplast and nucleus, and were embedded in a gel-like matrix. To maintain position in the cardia, parasites commonly inserted the flagellum deep into microvilli or cytoplasm of the epithelium; adherence to the cuticular intima of the stomodeal valve was by flagellar modification and formation of hemidesmosome plaques. Paramastigotes occurred in the esophagus, were sometimes degenerated in appearance, and were attached via flagellar hemidesmosomes. Paramastigotes observed in the lumen of the pharynx were commonly degenerated and were not attached to the intima. L. m. mexicana was able to colonize the various gut habitats of Lu. abonnenci by a number of adaptations; this sand fly appears to be a suitable biological host for the parasite.

Seroepidemiology of California and Bunyamwera serogroup (Bunyaviridae) virus infections in native populations of Alaska.

This study investigated the geographic distribution and prevalence of antibodies to California and Bunyamwera serogroup viruses in Native populations of Alaska, and demographic and ecologic risk factors associated with exposure. Sera (n = 1,635) from 18 communities were screened using an ELISA. All age groups were tested for antibodies to Jamestown Canyon (JC), Inkoo (INK), snowshoe hare (SSH), and Northway (NOR) viruses; persons > or = 45 years old (n = 90) from six communities were additionally tested for antibodies to Tahyna (TAH), Batai (BAT), Cache Valley (CV), and Sindbis (SIN) viruses. Thirty free-ranging mammals were tested by a plaque reduction neutralization test (PRNT) for antibodies to all eight viruses and to Getah (GET) virus. In Natives, overall antibody prevalence was 24.9% (JC = 17.6%, monotypic JC = 6.5%, INK = 11.1%, monotypic INK = 0.6%, SSH = 6.8%, monotypic SSH = 3.5%, and NOR = 6.2%). Five TAH, CV, and BAT virus exposures may be serologic cross-reactions, and no SIN virus antibodies were detected. Sindbis-like virus antibodies were found in 30% of the mammals. Most mammals had antibodies to NOR (83.3%) and California serogroup (70.0%) viruses; no GET virus exposures were found. Significant risk factors for human bunyavirus exposures were age group, ethnic-linguistic group, biotic province, climate zone, terrestrial vegetation, and presence of some ungulates and small mammals in communities. Sex was not a significant risk factor.

Ultrastructural biology of Leishmania (Viannia) panamensis (=Leishmania braziliensis panamensis) in Lutzomyia gomezi (Diptera: Psychodidae): a natural host-parasite association.

The development of Leishmania (Viannia) panamensis in a natural sand fly host, Lutzomyia gomezi, was studied by light and transmission electron microscopy. New aspects of peripylarian parasite behavior and morphology in the sand fly gut, early bloodmeal stages, and ultrastructural development in the anterior gut were documented. Eight distinct morphological forms were observed in the life cycle of the parasite within the insect. In the bloodmeal, amastigotes (1) transformed into stumpy promastigotes (2) which rapidly multiplied, resulting in spatulate-shaped nectomonad promastigotes (3) and elongate nectomonad promastigotes (4). These latter forms migrated primarily into the hindgut, where both were observed attached (=haptomonad phase) to the cuticular intima by hemidesmosomes within extremely shortened flagella. Spatulate haptomonad promastigotes predominated, colonizing the entire length of the hindgut, with the greatest density at 2 disjunct sites: the pylorus/ileum and the anterior rectum/rectal sac. Paramastigotes and dividing flagellates were rare. Some parasites migrated directly to the cardia/stomodeal valve region without a hindgut phase; however, major movement anteriorly was from the hindgut beginning at 6 days postinfection. In the cardia lumen, dividing short Type A promastigotes (5) predominated, intermixed with short Type B promastigotes with longer flagella (6). Paramastigotes (7) were free-swimming in the lumen as well as attached to the stomodeal valve. The primary colonizers of the valve were pear-shaped haptomonad promastigotes (8), with flagella of variable lengths and multi-segmented hemidesmosomal attachment points to the intima. Promastigotes and paramastigotes colonized the esophagus-pharynx region and attached to the foregut lining by flagellar hemidesmosomes. Both forms may represent infective stages of L. (V.) panamensis; however, no parasites were detected in the cibarium or proboscis. L. (V.) panamensis appeared well-adapted to the gut of Lu. gomezi, multiplying extensively at 2 sites, changing morphological form, and adhering to host surfaces by variously modified flagellar hemidesmosomes.

Ultrastructural development of Leishmania chagasi in its vector, Lutzomyia longipalpis (Diptera: Psychodidae).

The development of Leishmania chagasi, etiologic agent of American visceral leishmaniasis, was studied by light and electron microscopy in the gut of the sand fly, Lutzomyia longipalpis, a natural vector. New aspects of suprapylarian Leishmania behavior were elucidated. In the sand fly midgut, amastigotes transformed into promastigotes (division promastigote I) during a first division sequence within the bloodmeal. Secondary division of these promastigotes resulted in a second form (division promastigote II), and these subsequently elongated into nectomonad promastigotes. Nectomonads existed in long and short populations which divided in the bloodmeal and throughout the midgut lumen after escape from the peritrophic membrane. Nectomonads adhered to the midgut cells in a highly organized manner, with their flagella embedded deep into microvilli and cytoplasm. Migration of parasites from the posterior midgut into the cardia/stomodeal valve region at 36 hr was associated with breakdown of the peritrophic membrane anteriorly. Posterior breakdown at 48 hr resulted in a peritrophic tube open at both ends containing some parasites within the digesting bloodmeal for up to 6 days postinfection. At the stomodeal valve, a myriad of slender and rounded promastigotes attached to the intima by flagellar hemidesmosomes; these may represent a transformation sequence from slender nectomonads to pear-shaped haptomonads. Pear-shaped forms appear to be precursors of paramastigotes, which also attached to the valve intima. Both rounded haptomonads and paramastigotes were found in the esophagus, dividing in a complex sequence initiated by posterior cleavage of the cytoplasm producing unique heart-shaped forms. Dividing paramastigotes also colonized the pharynx up to the cibarial valve. The ultrastructure of paramastigotes suggested that they may be infective forms, capable of some motility in the foregut. Free-swimming "infective" promastigotes were observed throughout the midgut and foregut, were attached in the pharynx (armature region), and were associated with the labrum-epipharynx of the proboscis in 3.6% of flies (16 days). The fine structure of hemidesmosomes in the foregut showed regional specializations, including the presence of plasmalemmar bridges in the gap space.