PREVALENCE AND MOLECULAR CHARACTERIZATION OF DIROFILARIA IMMITIS (FILARIOIDEA: ONCHOCERCIDAE) IN DOGS FROM ENDEMIC AREAS OF RIO DE JANEIRO STATE, BRAZIL.

Canine dirofilariasis is common in Brazil, but molecular diagnosis is rare even though molecular studies increase our knowledge about molecular epidemiology and circulating genotypes from helminths worldwide. This study aims to estimate the prevalence of infection with a modified Knott's test and to perform molecular characterization of Dirofilaria immitis (Leidy, 1856) Railliet and Henry, 1911, in dogs from endemic areas of Maricá and Niterói municipalities, Rio de Janeiro State, Brazil. Molecular characterization was performed in 33 blood samples from dogs positive for microfilariae and 4 adult worms obtained from 2 other dogs. DNA extraction followed by PCR for mitochondrial target 12S rDNA and cytochrome oxidase subunit 1 (COI) of D. immitis were performed, and the amplified products were sequenced. All sequences were identical for both gene targets and showed 100% identity with D. immitis sequences from different animal species from various countries. The study concluded that this genotype of D. immitis might be dispersed worldwide.

Beneficial metabolic actions of a stable GIP agonist following pre-treatment with a SGLT2 inhibitor in high fat fed diabetic mice.

The purpose of the present study was to examine if a stable glucose-dependent insulinotropic polypeptide (GIP) agonist could exert beneficial metabolic control in diabetic mice which had been pre-treated with sodium-glucose-cotransporter-2 (SGLT2) inhibitor dapagliflozin (DAPA). High fat fed mice administered low dose streptozotocin (STZ) received vehicle, DAPA once-daily over 28 days, or DAPA once-daily for 14 days followed by (DAla(2))GIP once-daily for 14 days. Energy intake, body weight, glucose and insulin concentrations were measured at regular intervals. Glucose tolerance, insulin tolerance test, dual-energy X-ray absorptiometry (DEXA) and pancreatic histology were examined. Once-daily administration of (DAla(2))GIP for 14 days in high fat fed diabetic mice pre-treated with DAPA demonstrated significant decrease in body weight, blood glucose and increased insulin concentrations which were independent of changes in energy intake. Similarly, glucose tolerance, glucose-stimulated insulin secretion, insulin sensitivity and HOMA-ß were significantly enhanced in (DAla(2))GIP-treated mice. DEXA analysis revealed sustained percentage body fat loss with no changes in lean mass, bone mineral content and density. Pancreatic immunohistochemical analysis revealed decreased islet number and increases in islet area, beta cell area and pancreatic insulin content. The DAPA-induced increase in alpha cell area was also reversed. Additional acute in vitro and in vivo experiments confirmed that the impaired action of (DAla(2))GIP under hyperglycaemic-induced conditions was significantly reversed by DAPA treatment. These data demonstrate that (DAla(2))GIP can exert beneficial metabolic control in high fat fed diabetic mice pre-treated with DAPA. The results highlight possibility of a targeted and personalized approach using a GIP agonist and SGLT2 inhibitor for the treatment of type 2 diabetes.

Non-invasive electrocardiographic assessments of cardiac autonomic modulation in individuals with spinal cord injury.

STUDY DESIGN: Review. OBJECTIVES: The purpose of this review is to discuss the utility of linear and non-linear heart rate variability (HRV) as well as the QT-variability index (QTVI) as indices of cardiac autonomic control in individuals with spinal cord injury (SCI). SETTING: Brock University, Department of Kinesiology, St Catharines, Ontario, Canada. Brock-Niagara Centre for Health and Well-being, St Catharines, Ontario, Canada. METHODS: Literature review. CONCLUSION: Non-invasive markers determined from the electrocardiogram, such as linear and non-linear HRV, and, more recently, the QTVI have all shown some promise as indices of cardiac autonomic regulation in the SCI population. However, there are inconsistencies in the literature that call to question their true validity in this regard. Studies using pharmacological blockade, sympathetic manoeuvres and exercise suggest that both linear and non-linear HRV reflect cardiac parasympathetic activity, whereas their ability to quantify cardiac sympathetic outflow remains uncertain. The QTVI, although a novel method, correlates with both limbs of the autonomic nervous system and therefore may hold value as a measure of both cardiac sympathetic and parasympathetic activity in individuals with SCI; however, more research is required to confirm its utility.

Sensitivity and specificity of serological tests, histopathology and immunohistochemistry for detection of Toxoplasma gondii infection in domestic chickens.

Since free-range chickens are important for the epidemiology of toxoplasmosis, this study evaluated the sensitivity and specificity of different laboratory techniques for the diagnosis of Toxoplasma gondii in these animals. Serum samples from 135 adult domestic chickens were tested for anti-T. gondii antibodies by the indirect fluorescent antibody test (IFAT), enzyme-linked immunosorbent assay (ELISA), modified agglutination test (MAT), and indirect hemagglutination test (IHAT). Tissue samples from all animals were analyzed by histopathology, immunohistochemistry and mouse bioassay (gold standard). Fifty-four chickens were positive for T. gondii in the bioassay. The sensitivity and specificity of the different tests were, respectively, 85% and 56% for ELISA; 80% and 52% for IFAT; 76% and 68% for MAT; 61% and 80% for IHAT; 7% and 98% for immunohistochemistry, and 6% and 98% for histopathology. The MAT was the most effective method for the diagnosis of T. gondii infection in chickens, followed by ELISA. Histopathology and immunohistochemistry are useful tools for the diagnosis of T. gondii infection in chickens due to their specificity.

Isometric handgrip training lowers blood pressure and increases heart rate complexity in medicated hypertensive patients.

Hypertension is characterized by elevated blood pressure (BP) and autonomic dysfunction, both thought to be improved with exercise training. Isometric handgrip (IHG) training may represent a beneficial, time-effective exercise therapy. We investigated the effects of IHG training on BP and traditional and nonlinear measures of heart rate variability (HRV). Pre- and post-measurements of BP and HRV were determined in 23 medicated hypertensive participants (mean ± SEM, 66 ± 2 years) following either 8 weeks of IHG training (n = 13) or control (n = 10). IHG exercise consisted of four unilateral 2-min isometric contractions at 30% of maximal voluntary contraction, each separated by 4 min of rest. IHG training was performed 3 days/week for 8 weeks. IHG training decreased systolic BP (125 ± 3 mmHg to 120 ± 2 mmHg, P < 0.05) and mean BP (90 ± 2 mmHg to 87 ± 2 mmHg, P < 0.05), while sample entropy was increased (1.07 ± 0.1 to 1.35 ± 0.1, P < 0.05) and the fractal scaling distance score was decreased (0.34 ± 0.1 to 0.19 ± 0.1, P < 0.05). No significant changes were observed in traditional spectral or time-domain measures of HRV or control participants. IHG training improves nonlinear HRV, but not traditional HRV, while reducing systolic and mean BP. These results may highlight the benefits of IHG training for patients with primary hypertension.

Autonomic recovery following sprint interval exercise.

The autonomic nervous activity was assessed following supramaximal exercise through heart rate (HR) and blood pressure (BP) variability (HRV and BPV) and baroreflex sensitivity (BRS). The beat-to-beat HR and BP were recorded during the supine and standing states before (PRE) and at 60 (R60) and 120 min (R120) following single (one Wingate, 1W) and multiple sprint intervals (four Wingates interspersed with 4 min of light cycling, 4W). The supine low frequency (LF) component was increased (P<0.001) and the high frequency (HF) was reduced (P<0.01) at R60 (LF, 178.1 ± 11.0; HF, 74.8 ± 10.5) compared with PRE (LF, 140.2 ± 7.4; HF, 110.4 ± 7.2) after both exercises. Supine systolic BPV LF:HF was higher at R60 (4.6 ± 1.4) compared with PRE (6.8 ± 2.4) only after 4W (P=0.035). Supine BRS was lower (P<0.001) at R60 (6.8 ± 1.1) than at PRE (15.3 ± 1.8) and R120 (11.3 ± 1.3). BRS at R120 remained lower after 4W (P=0.02). Standing BRS was less (P<0.001) at R60 (2.3 ± 0.5) than at PRE (5.6 ± 0.8) or R120 (3.7 ± 0.6) and returned to PRE values only after 1W. We concluded that (a) autonomic balance is shifted to a greater sympathetic and less parasympathetic activation following both types of exercise, (b) it takes longer than 1 h to recover following supramaximal exercise and (c) the recovery is longer after 4W than 1W.

Effects of isometric handgrip protocol on blood pressure and neurocardiac modulation.

Isometric handgrip (IHG) remains a well-studied cardiovascular and autonomic stimulus, however the effects of rhythmic IHG protocols remain largely unknown. The purpose of this study was to investigate the acute effects of 4 IHG protocols on blood pressure (BP) and neurocardiac reactivity and recovery responses. 12 healthy older participants (70±5 yrs, ♀=4) each completed 4 bilateral 12-min protocols (sham, IHG1, IHG2, IHG3) on separate visits. IHG1, IHG2, and IHG3 consisted of 4×2-min, 8×1-min, and 16×30-s isometric contractions, respectively, each completed at 30% MVC, while sham consisted of 4×2-min contractions completed at 3% MVC. BP and neurocardiac modulation were assessed during and following each protocol. Systolic BP (SBP) reactivity was increased during IHG1 compared to IHG2 (p<0.05), IHG3 (p<0.05), and sham (p<0.01), although during recovery delta SBP was lower following IHG1 (p<0.01), IHG2 (p<0.01), and IHG3 (p<0.05), compared to sham. Sample entropy, a measure of nonlinear heart rate variability was reduced during IHG1 (p<0.01) and IHG2 (p<0.05), while increased following IHG1 (p<0.05) and IHG3 (p<0.05), compared to sham. In conclusion, recovery responses from rhythmic IHG appear independent of contraction and/or rest period frequency-duration relationships. Investigation of rhythmic IHG protocols warrants further examination.

Power scaling of Nd:YVO4 and Nd:GdVO4 disk lasers using synthetic diamond as a heat spreader.

A newly developed low-birefringence synthetic diamond is shown to be an effective intracavity heat spreader in Nd:YVO4 and Nd:GdVO4 disk lasers. A cw output power of 25.7 W from only one double pass of the pump is reported. The diamond heat spreader is shown to increase the pump power density at which fracture occurs.

Skill shortages in health: innovative solutions using vocational education and training.

INTRODUCTION: This article reports findings of a project funded by the Australian National Council for Vocational Education Research. The project explores solutions to current and projected skills shortages within the health and community services sector, from a vocational education and training perspective. Its purpose is to locate, analyse and disseminate information about innovative models of health training and service delivery that have been developed in response to skill shortages. METHODS: The article begins with a brief overview of Australian statistics and literature on the structure of the national health workforce and perceived skill shortages. The impact of location (state and rurality), demographics of the workforce, and other relevant factors, on health skill shortages is examined. Drawing on a synthesis of the Australian and international literature on innovative and effective models for addressing health skill shortages and nominations by key stakeholders within the health sector, over 70 models were identified. The models represent a mixture of innovative service delivery models and training solutions from Australia, as well as international examples that could be transposed to the Australian context. They include the skill ecosystem approach facilitated by the Australian National Training Authority Skill Ecosystem Project. Models were selected to represent diversity in terms of the nature of skill shortage addressed, barriers overcome in development of the model, healthcare specialisations, and different customer groups. RESULTS: Key barriers to the development of innovative solutions to skills shortages identified were: policy that is not sufficiently flexible to accommodate changing workplace needs; unwillingness to risk take in order to develop new models; delays in gaining endorsement/accreditation; current vocational education and training (VET) monitoring and reporting systems; issues related to working in partnership, including different cultures, ways of operating, priorities and timelines; workplace culture that is resistant to change; and organisational boundaries. For training-only models, additional barriers were: technology; low educational levels of trainees; lack of health professionals to provide training and/or supervision; and cost of training. Key enhancers for the development of models were identified as: commitment by all partners and co-location of partners; or effective communication channels. Key enhancers for model effectiveness were: first considering work tasks, competencies and job (re)design; high profile of the model within the community; community-based models; cultural fit; and evidence of direct link between skills development and employment, for example VET trained aged care workers upskilling for other health jobs. For training only models, additional enhancers were flexibility of partners in accommodating needs of trainees; low training costs; experienced clinical supervisors; and the provision of professional development to trainers. CONCLUSIONS: There needs to be a balance between short-term solutions to current skill shortages (training only), and medium to longer term solutions (job redesign, holistic approaches) that also address projected skills shortages. Models that focus on addressing skills shortages in aged care can provide a broad pathway to careers in health. Characteristics of models likely to be effective in addressing skill shortages are: responsibility for addressing skills shortage is shared between the health sector, education and training organisations and government, with employers taking a proactive role; the training component is complemented by a focus on retention of workers; models are either targeted at existing employees or identify a target group(s) who may not otherwise have considered a career in health.

Frequência de enteroparasitas em amostras fecais de cães e gatos dos municípios do Rio de janeiro e Niterói / Frequency of enteric parasites in fecal samples of dogs and cats in Rio de Janeiro and Niterói

Foram analisadas 252 amostras de fezes de cães e gatos provenientes dos municípios do Rio de Janeiro e Niterói no período de 1999 a 2000. Foram 212 (84,12

Freqüência de enteroparasitas em amostras fecais de cães e gatos dos municípios do Rio de Janeiro e Niterói

Foram analisadas 252 amostras de fezes de cães e gatos provenientes dos municípios do Rio de Janeiro e Niterói no períodode 1999 a 2000. Foram 212 (84,12%) amostras de cães e 40 (15,87%) de gatos. Do total de amostras examinadas 81(32,14%), foram positivas para pelo menos uma espécie de parasita. Dos 212 exames de material fecal canino, 70 (33,01%)estavam positivos e de felinos 11 (27,5%). As infecções mistas foram observadas em 10 amostras caninas (14,28%) e quatrofelinas (36,36%). Nas amostras caninas, ovos de ancilostomídeos foram os mais encontrados em 43 (61,43%) amostras,enquanto os coccídeos foram mais freqüentemente observados nas fezes de felinos em três (27,27%) amostras. Quanto àidade dos animais, 37 (52,85%) amostras positivas eram provenientes de animais com mais de 1 ano de idade, indicandoprovável vermifugação dos filhotes, enquanto nos gatos a faixa etária mais parasitada foi de menos de seis meses, com 7(63,63%) positivos.

Second-harmonic generation from a first-order quasi-phase-matched GaAs/AlGaAs waveguide crystal.

We demonstrate, for the first time to our knowledge, the generation of second-harmonic pulses by use of a novel methodology for achieving first-order quasi-phase matching in a semiconductor waveguide crystal. This methodology is based on a periodic modulation of the susceptibility coefficient along the direction of light-beam propagation in which advantage is taken of the fact that chi((2))(GaAs)>chi((2))(Al(x)Ga(1-x)As) . Efficient second-harmonic generation at 975 nm of a pump wavelength of 1950 nm has been demonstrated for a crystal with a nonuniform domain dimension (duty cycle, ~39/61).

Spectral features associated with nonlinear pulse compression in Bragg gratings.

We report, for the first time to our knowledge, direct spectral measurements of nonlinear spectral broadening caused by nonlinear propagation through Bragg gratings written on integrated AlGaAs waveguides. The spectral broadening is associated with pulse compression from 400 to 80 ps. The high nonlinearity of AlGaAs enables high-repetition-rate, low-peak-power sources to be used, facilitating easy spectral measurements.

Nonlinear propagation effects in an AlGaAs Bragg grating filter.

We present experimental observations of nonlinear propagation effects in an integrated AlGaAs waveguide filter. We demonstrate pulse shaping, pulse compression, and the production of gap solitons within the stop band of the grating for switching powers of approximately 130 W . This nonlinear behavior is associated with the counterbalancing effects of self-phase modulation and the large dispersion effects introduced by the grating itself.

Laser remote-sensing system analysis for search and rescue.

We develop a general model of a laser remote-sensing system for search and rescue using targets marked with fluorescent dye. The dye fluoresces at a longer peak wavelength than the incident radiation, enabling a dye-covered target to be distinguished from the unshifted ground echo by the search system. The principal result is a simple expression derived for the average laser power required to search at a particular rate given a required ground energy density. A similar expression is applicable to imaging lidar systems. The example system shown indicates that active probing for lost planes may be practical.

Dynamic, electronically controlled angle steering of spatial solitons in AlGaAs slab waveguides.

We demonstrate experimentally that spatial solitons in AlGaAs slab waveguides can be deflected by an electronically induced prism. We also show that a weak signal beam can be guided and steered by the solitons, thus demonstrating the feasibility of a dynamically reconfigurable optical interconnect.

A two-year dietary carcinogenicity study of the antiestrogen toremifene in Sprague-Dawley rats.

The carcinogenic potential of the nonsteroidal triphenylethylene antiestrogen toremifene (Fareston) was evaluated in a standard 104-week rat dietary carcinogenicity study. The doses were 0, 0.12, 1.2, 5.0 and 12 mg/kg/day and the number of animals 50/sex/dose group. The body weight gain and food consumption were monitored once weekly (study weeks 1-16) or once every four weeks thereafter (study weeks 17-104). Blood samples were taken at weeks 34, 52 and 104 and the plasma concentrations of toremifene, as well as the two main metabolites (deaminohydroxy)toremifene and N-demethyltoremifene, were measured. All doses of toremifene reduced food intake and body weight gain. Toremifene caused a significant reduction in mortality, which was mainly due to reduced incidences of pituitary tumors. This was evident in all dose groups. Drug-related decrease of mammary tumors in females (at all doses) and testicular tumors in male rats (doses > or = 1.2 mg/kg/day) were also evident. The incidence of the preneoplastic foci of basophilic hepatocytes were significantly decreased in treated female groups. Toremifene induced no preneoplastic or neoplastic lesions. Based on histopathology, no obvious toxicity could be observed. Drug-related changes were observed in the genital organs, thyroid, spleen, mammary gland, adrenal, kidney, stomach and lung. These changes were due to hormonal disturbances or as a result of reduced food consumption or reduced incidences of pituitary, mammary or testicular tumors. This study indicates that toremifene is an efficient antiestrogen in long-term treatment, is well tolerated and has no tumorigenic potential in rats.

Bovine T cells preferentially recognize non-viral spacer epitopes in a putative FMDV vaccinal peptide.

In a group of immunized cattle with a variety of MHC class II types, T-cell responses were detected to a synthetic peptide (FMDV15) proposed as a basis for a vaccine against foot-and-mouth disease. This peptide combines the loop region of VP1 with the C-terminal sequence connected by a spacer (PPS). Two major immunodominant regions of FMDV15 for bovine T cells were detected, one within the loop region and the other around the spacer. A substantial proportion of the T-cell response to FMDV15 was directed to the spacer region in 5/12 animals, and in vitro generation of FMDV15-specific T cells preferentially selected for spacer-specific T cells. This pattern of response was associated with a particular MHC class II type which is very common in cattle. Focusing of the T-cell response to non-native virus epitopes may explain why FMDV15 is inefficient at inducing protection.

Induction of effective cross-reactive immunity by FMDV peptides is critically dependent upon specific MHC-peptide-T cell interactions.

BoCD4+ T-cell clones specific for a peptide derived from foot-and-mouth disease virus envelope protein, VP1 (FMDV15) were generated from two responder cattle. One animal was a high and the other was an intermediate responder in terms of both T-cell and antibody responses. However both animals had identical major histocompatibility complex (MHC) class II DR-like types (DRBF3,6) according to a one-dimensional isoelectric focusing method which distinguishes DR-like alleles. In contrast, mixed lymphocyte reaction (MLR) responses indicated that they shared only one haplotype (DRBF3) and anti-DRBF6 alloclones also differentiated between the animals. This suggested that the animals differed at a non-DR-like locus. Restriction patterns of FMDV-specific clones derived from these animals indicated that FMDV15 was presented by the non-DR-like class II molecules associated with DRBF6. Only one clone, derived from the high responder animal, was restricted to DRBF3. Thus products from the non-DR-like locus (probably DQ-like) are functionally important for presentation of FMDV peptides. Furthermore the allelic differences detected by the alloclones are also critical for peptide binding. The majority of clones from the high responder animal recognized an immunodominant region containing a Rothbard epitope whereas none of the clones from the intermediate responder did so. This suggests that the region recognized by T cells, which is dependent upon MHC type, influences the B-cell response and thus the degree of protection obtained. This has major implications for rational vaccine design involving T- and B-cell epitopes.