Effects of a novel bites, steps and eating rate-focused weight loss randomised controlled trial intervention on body weight and eating behaviours.

BACKGROUND: Eating rate (ER), comprising the amount of food consumed per unit of time, is associated with obesity and energy intake (EI). METHODS: The present study tested whether adding a self-monitoring wearable device to a multifaceted 8-week weight loss intervention increased weight loss. In addition, the device's effect on secondary change outcomes in EI, ER and estimated energy expenditure was explored. Tertiary outcomes included examining eating behaviours measured by the Weight-Related Eating Questionnaire (WREQ). Seventy-two adults who were overweight or obese [mean (SD) age, 37.7 (15.3) years; body mass index, 31.3 (3.2) kg m-2 ] were randomised into two groups: intervention workbook plus device (WD) or intervention workbook only (WO). Three 24-h dietary recalls were obtained before weeks 0 and 8. Participants were weighed, consumed a test meal and completed 7-day Physical Activity Recall and WREQ at weeks 0 and 8. RESULTS: There was no significant difference between WD and WO groups with respect to weight change [-0.46 (1.11) vs. 0.26 (0.82) kg, respectively], ER, EI, energy expenditure or WREQ scores, although there were significant changes over time, and within-group changes on all of these variables. At week 8, participants were dichotomised into weight loss or weight stable/gainers groups. A significant time by group change was seen in susceptibility to external cues scores, with significant time effects for susceptibility and restraint. CONCLUSIONS: An intervention focused on reducing ER, energy density and increasing steps was effective for weight loss, although the wearable device provided no additional benefit. Participants with higher susceptibility to external eating may be more responsive to this intervention.

The ionic mechanism of membrane potential oscillations and membrane resonance in striatal LTS interneurons.

Striatal low-threshold spiking (LTS) interneurons spontaneously transition to a depolarized, oscillating state similar to that seen after sodium channels are blocked. In the depolarized state, whether spontaneous or induced by sodium channel blockade, the neurons express a 3- to 7-Hz oscillation and membrane impedance resonance in the same frequency range. The membrane potential oscillation and membrane resonance are expressed in the same voltage range (greater than -40 mV). We identified and recorded from LTS interneurons in striatal slices from a mouse that expressed green fluorescent protein under the control of the neuropeptide Y promoter. The membrane potential oscillation depended on voltage-gated calcium channels. Antagonism of L-type calcium currents (CaV1) reduced the amplitude of the oscillation, whereas blockade of N-type calcium currents (CaV2.2) reduced the frequency. Both calcium sources activate a calcium-activated chloride current (CaCC), the blockade of which abolished the oscillation. The blocking of any of these three channels abolished the membrane resonance. Immunohistochemical staining indicated anoctamin 2 (ANO2), and not ANO1, as the CaCC source. Biophysical modeling showed that CaV1, CaV2.2, and ANO2 are sufficient to generate a membrane potential oscillation and membrane resonance, similar to that in LTS interneurons. LTS interneurons exhibit a membrane potential oscillation and membrane resonance that are both generated by CaV1 and CaV2.2 activating ANO2. They can spontaneously enter a state in which the membrane potential oscillation dominates the physiological properties of the neuron.

Evaluation of polybrominated diphenyl ethers (PBDEs) in matched cat sera and house dust samples: investigation of a potential link between PBDEs and spontaneous feline hyperthyroidism.

The cause of feline hyperthyroidism (FH), a common endocrinopathy of domestic cats, is unknown. A potential association between exposure to environmental contaminants polybrominated diphenyl ethers (PBDEs) and FH was investigated. The median serum level for the sum of congeners BDE-47, BDE-99, BDE-153, BDE-154 and BDE-183 (Σ5) in hyperthyroid and euthyroid cats was 82 and 174 ng g(-1)lw respectively with no significant difference in PBDE levels or profiles between groups. Overall, the median (min to max) concentration of PBDEs in cat serum (n=65) was 118 ng g(-1)lw (5-5260 ng g(-1)lw), which is approximately 10 times higher than that observed in the Australian human population. Furthermore, congener composition in feline serum samples was dominated by congener BDE-99, followed by BDE-47 then BDE-153 which differs from results of human biomonitoring. There was no correlation between PBDE levels in feline serum samples and matched house dust samples (n=25). However the similarity of BDE-47/99 ratio in each matrix suggests dust is likely the dominant exposure. Calculation of the daily exposure dose via dust ingestion for cats equated to a mean of 33 ng kg(-1) bw d(-1) (0.2-150 ng kg(-1) bw d(-1)). Differences in exposure estimates for Australian and US cats, based on dust ingestion alone, are consistent with the observed differences in body burdens. Our results do not support a role for PBDE exposure in the aetiopathogenesis of FH.

Low prevalence of Babesia hongkongensis infection in community and privately-owned cats in Hong Kong.

Domestic cats are susceptible to infection with at least 11 species of Babesia. In Hong Kong, where dogs are commonly infected with B. gibsoni, a single infection in a cat by a novel species, B. hongkongensis, was reported previously. The aim of this study was to investigate the frequency of Babesia spp. detection in cats in Hong Kong. Residual blood-derived DNA from healthy free-roaming community cats (n = 239), and privately-owned cats with and without anaemia undergoing diagnostic investigations (n = 125) was tested for Babesia spp. DNA using a pan-Babesia PCR targeting mitochondrial Cytochrome B, and a B. hongkongensis specific PCR targeting 18S rRNA. Positive samples were confirmed by sequencing and comparative sequence analysis against the GenBank nucleotide database. Babesia hongkongensis was detected in 4/239 (1.7 %) community cats, and 0/125 (0.0 %) privately-owned cats. Babesia gibsoni was detected in 0/239 community cats and 1/125 (0.8 %) privately-owned cats. Cats infected with B. hongkongensis were clinically healthy at the time of sampling. The B. gibsoni-infected cat was anaemic and thrombocytopenic. Cats in Hong Kong can be infected with B. hongkongensis and B. gibsoni, albeit at low frequency. The tick vector for B. hongkongensis is yet to be identified.

Erythrocytic pyruvate kinase deficiency and AB blood types in Australian Abyssinian and Somali cats.

OBJECTIVE: To determine the frequency of the mutant pyruvate kinase (PK) allele, haematological parameters and AB blood types of Abyssinian and Somali cats in Australia. DESIGN: Complete blood cell and reticulocyte counts, DNA PK mutation testing and blood typing were performed in all cats. RESULTS: A total of 60 cats (36 Abyssinians, 24 Somalis) were included (37 females, 23 males). For the mutant PK allele, three female Somalis were homozygous (affected, 5%), 17 cats were heterozygous (carrier, 28%) and 40 cats tested negative (normal, 67%). Pedigree analysis revealed common ancestry of affected and many carrier cats. Of affected cats, two had regenerative anaemias and all had reticulocytosis (range 64-390 x 10(9)/L; P < 0.001 compared with normal or carrier cats). The only consistent historical sign was lethargy. One affected cat was euthanased 18 months after testing, because of anaemia, neutropenia, anorexia and weight loss. The mutant allele frequency was 0.19 overall (0.29 in Somalis, 0.13 in Abyssinians). All cats had blood type A. The commercial blood typing card method incorrectly identified 12 cats as having type AB blood. CONCLUSIONS: The frequency of the mutant PK allele is high in Australia. Screening for PK deficiency is indicated before mating and in individual cats of these breeds, even in the absence of anaemia and especially when there is reticulocytosis. Although all cats in the present study had blood type A, blood type B is common in these breeds worldwide. Retyping of any AB typed cats by a laboratory technique is recommended.

Shelter-housed cats show no evidence of faecal shedding of canine parvovirus DNA.

Canine parvovirus (CPV) and feline panleukopenia virus (FPV) are deoxyriboncucleic acid (DNA) viruses in the taxon Carnivore protoparvovirus 1. Exposure of cats to either CPV or FPV results in productive infection and faecal shedding of virus. Asymptomatic shedding of CPVs by one-third of shelter-housed cats in a UK study suggests that cats may be an important reservoir for parvoviral disease in dogs. The aim of this cross-sectional study was to determine the prevalence of faecal shedding of CPVs in asymptomatic shelter-housed cats in Australia. Faecal samples (n=218) were collected from cats housed in three shelters receiving both cats and dogs, in Queensland and NSW. Molecular testing for Carnivore protoparvovirus 1 DNA was performed by polymerase chain reaction (PCR) amplification followed by DNA sequencing of the VP2 region to differentiate CPV from FPV. Carnivore protoparvovirus 1 DNA was detected in only four (1.8%, 95% confidence interval 0.49-4.53%) faecal samples from a single shelter. Sequencing identified all four positive samples as FPV. Faecal shedding of CPV by shelter-cats was not detected in this study. While the potential for cross-species transmission of CPV between cats and dogs is high, this study found no evidence of a role for cats in maintaining CPV in cat and dog populations through faecal shedding in the regions tested.

Vaccine protection against feline immunodeficiency virus: setting the challenge.

Since feline immunodeficiency virus (FIV) was first isolated, international research efforts have been directed towards developing a protective vaccine, not least because it may provide a model for a candidate human immunodeficiency virus (HIV) vaccine. This article reviews the challenges facing vaccine development, the current state of knowledge and future prospects for FIV vaccination.

Intracranial empyema: literature review and two novel cases in cats.

OBJECTIVES: To review the literature on intracranial empyema and report two new cases in cats. METHODS: Literature review and case reports. RESULTS: Intracranial empyema has been rarely reported in small animals. In two novel cases in cats, the route of infection was postulated to be local extension from a retrobulbar abscess of odontogenic origin in one case and direct inoculation from a penetrating bite wound to the skull, confirmed at post-mortem examination, in the other. On magnetic resonance imaging of the first case, there was a contrast-enhancing large extra-axial fluid collection overlying the right cerebral hemisphere, consistent with subdural empyema. Infection was caused by an Actinomyces spp. This is the first report of successful treatment of intracranial empyema by craniotomy, drainage and antibiotics. CLINICAL SIGNIFICANCE: Intracranial empyema is a neurosurgical emergency. Favourable outcomes may be achieved with surgical decompression, antimicrobial therapy and intensive care.

Antemortem diagnosis and treatment of toxoplasmosis in two cats on cyclosporin therapy.

Clinical toxoplasmosis was diagnosed antemortem in two cats being treated with therapeutic doses of cyclosporin. The diagnosis was made by detecting tachyzoites on cytological examination of bronchoalveolar lavage fluid from one case and pleural effusion from the other. Despite early diagnosis and aggressive treatment in both cases, only one cat survived. Reactivation of latent Toxoplasma gondii infection secondary to cyclosporin-induced immunosuppression was considered likely in both cases. The presence of respiratory signs in cats treated with cyclosporin should alert clinicians to the possibility of clinical toxoplasmosis. Consideration should be given to determining the serostatus of cats to T gondii prior to use of drugs which are potent inhibitors of cell mediated immunity, such as cyclosporin. Two cases of feline toxoplasmosis are presented.

High prevalence of Felis catus gammaherpesvirus 1 infection in haemoplasma-infected cats supports co-transmission.

Felis catus gammaherpesvirus 1 (FcaGHV1), a potential feline pathogen, has been identified in domestic cats from USA, Asia-Pacific and Central Europe. Transmission of FcaGHV1 during territorial encounters, a route not typical for gammaherpesviruses, is suggested by risk factor analyses from some regions. The aim of this study was to investigate the relationship between FcaGHV1 detection and risk factors, including haemoplasma co-infections, among UK cats to better understand transmission and global distribution of FcaGHV1. FcaGHV1 DNA was detected in blood samples from UK cats (11.56%; 95% confidence interval [CI], 7.47-16.84; n = 199). Logistic regression analyses showed that entire male cats were more likely to be FcaGHV1 positive than neutered male cats (odds ratio, 3.60; 95% CI, 1.22-10.46). Samples positive for DNA from any of three haemoplasma species had 19 times greater odds for testing positive for FcaGHV1 than haemoplasma negative cats in multivariable analyses after adjusting for age, sex and neuter status. Domestic cats in the UK can be infected with FcaGHV1, confirming that this virus is globally endemic. The identification of neuter status as a risk factor for FcaGHV1 detection provides further evidence to support transmission of this virus during territorial encounters and co-transmission with haemoplasmas is suggested.

Immunohistochemical Analysis of Leucocyte Subsets in the Sinonasal Mucosa of Cats with Upper Respiratory Tract Aspergillosis.

Leucocyte populations in the sinonasal mucosa of cats with and without upper respiratory tract aspergillosis were compared using immunohistochemistry and computer-aided morphometry. Inflammation was identified in the nasal mucosa of all affected cats, comprising predominantly of lymphoplasmacytic infiltration of the lamina propria associated with epithelial proliferation and degeneration. There was intense and diffuse expression of class II antigens of the major histocompatibility complex, associated with sites of hyphal invasion with hyperplasia and ulceration of the epithelium adjacent to fungal elements. Significantly more CD79b(+) cells, total lymphocytes, immunoglobulin (Ig)-expressing cells and MAC387(+) cells infiltrated the epithelium and more IgG(+) cells and total Ig-expressing cells infiltrated the lamina propria in affected cats compared with controls. Importantly, the inflammatory profile in affected cats was not consistent with the T helper (Th)1 and Th17 cell-mediated response that confers protective acquired immunity against invasive aspergillosis in dogs and people and in murine models of the infection. This finding may help to explain the development of invasive aspergillosis in systemically immunocompetent cats.

Evaluation of Serum Aspergillus-Specific Immunoglobulin A by Indirect ELISA for Diagnosis of Feline Upper Respiratory Tract Aspergillosis.

BACKGROUND: Serological tests for diagnosis of aspergillosis in immunocompetent humans and animals are based on Aspergillus-specific IgG (As-IgG). In humans with chronic pulmonary aspergillosis, As-IgA may be detectable even if IgG titers are negative. Cats with upper respiratory tract aspergillosis (URTA) have detectable As-IgG, but their ability to mount an IgA response and its diagnostic utility are unknown. OBJECTIVES: To determine whether serum As-IgA can be detected in cats with URTA and evaluate its diagnostic utility alone or combined with As-IgG. ANIMALS: Twenty-three cats with URTA (Group 1), 32 cats with other respiratory diseases (Group 2), and 84 nonrespiratory controls (Group 3). METHODS: Serum As-IgA and As-IgG was measured by indirect ELISA. Optimal cutoff values were determined by receiver-operating curve analysis. Sensitivity (Se) and specificity (Sp) for URTA diagnosis were determined. RESULTS: Serum IgA was detected in 91.3% of Group 1 cats. The Se of IgA detection was 78.3% and Sp was 96.9% for Group 2, 85.7% for Group 3 and 88.8% for Group 2 and 3 combined. Assay Se for IgG was 100% and Sp was 92.2%. Using combined IgA and IgG results at cutoffs optimized for Sp for IgA and Se for IgG and combined controls (Groups 2 and 3), Se for diagnosis was 100% and Sp was 91.4%. CONCLUSION AND CLINICAL IMPORTANCE: Most cats with URTA have serum As-IgA antibodies that can be detected by ELISA. Paired measurement of serum As-IgA and IgG shows no benefit for diagnosis of feline URTA over IgG alone.

Detection of Aspergillus-specific antibodies by agar gel double immunodiffusion and IgG ELISA in feline upper respiratory tract aspergillosis.

Feline upper respiratory tract aspergillosis (URTA) is an emerging infectious disease. The aims of this study were: (1) to assess the diagnostic value of detection of Aspergillus-specific antibodies using an agar gel double immunodiffusion (AGID) assay and an indirect immunoglobulin G (IgG) ELISA; and (2) to determine if an aspergillin derived from mycelia of Aspergillus fumigatus, Aspergillus niger and Aspergillus flavus can be used to detect serum antibodies against cryptic Aspergillus spp. in Aspergillus section Fumigati. Sera from cats with URTA (group 1: n = 21) and two control groups (group 2: cats with other upper respiratory tract diseases, n = 25; group 3: healthy cats and cats with non-respiratory, non-fungal illness, n = 84) were tested. Isolates from cats with URTA comprised A. fumigatus (n = 5), A. flavus (n = 1) and four cryptic species: Aspergillus felis (n = 12), Aspergillus thermomutatus (Neosartorya pseudofischeri, n = 1), Aspergillus lentulus (n = 1) and Aspergillus udagawae (n = 1). Brachycephalic purebred cats were significantly more likely to develop URTA than other breeds (P = 0.013). The sensitivity (Se) of the AGID was 43% and the specificity (Sp) was 100%. At a cut-off value of 6 ELISA units/mL, the Se of the IgG ELISA was 95.2% and the Sp was 92% and 92.9% for groups 2 and 3 cats, respectively. Aspergillus-specific antibodies against all four cryptic species were detected in one or both assays. Assay Se was not associated with species identity. Detection of Aspergillus-specific antibodies by IgG ELISA has high Se and Sp for diagnosis of feline URTA.

Involvement of gag- and env-specific cytotoxic T lymphocytes in protective immunity to feline immunodeficiency virus.

Definition of the immunological mechanisms involved in protective immunity against lentiviral infections is crucial to the development of an effective vaccine. The induction of gag- and env-specific cell-mediated immune responses was studied in cats following vaccination with whole inactivated feline immunodeficiency virus (FIV). Cats were immunized by inoculation with three doses of paraformaldehyde-inactivated FIV, derived from the feline lymphoid cell line, FL-4, which is persistently infected with the Petaluma isolate of FIV. Autologous or allogeneic skin fibroblasts either infected with recombinant FIV gag- or env-vaccinia virus or pulsed with FIV env peptides were used as targets in chromium-51 release assays. Effector cells were fresh peripheral blood mononuclear cells. Following the third immunization, all vaccinated cats, but none of the control cats immunized with adjuvant alone, had detectable FIV env-specific lymphocytotoxicity in their peripheral blood. Two cats also exhibited gag-specific activity. There was no recognition of either allogeneic skin fibroblasts infected with recombinant vaccinia virus or autologous target cells infected with wild-type vaccinia virus, indicating the specificity and MHC-restricted nature of the response. Vaccinated cats, but not control cats, were protected from challenge with the homologous Petaluma isolate of FIV. Partial epitope mapping of the env-specific cytotoxic response was performed using overlapping 10-amino acid peptides from the env V3 domain of FIV. This response appeared to be directed at env peptide 1 (RAISSWKQRN) and env peptide 3 (QRNRWEWRPD), which lie adjacent to a beta-turn within the V3 domain.(ABSTRACT TRUNCATED AT 250 WORDS)

Chronic exercise increases GAD gene expression in the caudal hypothalamus of spontaneously hypertensive rats.

Previous studies have suggested that a gamma-amino-butyric acid (GABA) deficit in the caudal hypothalamus (CH) of the spontaneously hypertensive rat (SHR) contributes to elevated levels of arterial pressure. The purpose of this study was to examine if SHR that underwent exercise training demonstrated a blunted development of hypertension and greater levels of glutamic acid decarboxylase (GAD) mRNA transcripts in the caudal hypothalamus. SHR were randomly paired and assigned to either a trained group (T; n=9) or a non-trained control group (NT; n=9). Trained animals were exercised for 10 weeks on a motorized treadmill while NT animals concurrently rested on a mock-treadmill. Following the 10-week training period, Northern blot analyses of mRNA for both the 65-kDa (GAD(65)) and 67-kDa (GAD(67)) isoforms of GAD were performed on tissue from caudal hypothalamic and cerebellar control brain regions. Exercise training simultaneously blunted the developmental rise in blood pressure in SHR (Delta59+/-9 mmHg in trained versus Delta77+/-9 mmHg in non-trained; P<0.03) and increased both GAD(65) (147+/-44%) and GAD(67) (162+/-77%) mRNA transcript levels in the CH (P<0.05). In contrast, no difference was detected in GAD mRNA levels in the cerebellum between T and NT SHR. These findings are consistent with our previous functional studies and demonstrate that exercise can significantly and specifically upregulate GAD gene transcript levels in the caudal hypothalamus of hypertensive rats.

Hypothalamus, hypertension, and exercise.

The hypothalamus is a well-known autonomic regulatory region of the brain involved in integrating several behaviors as well as cardiorespiratory activity. Our laboratory has shown that the caudal hypothalamus modulates the cardiorespiratory responses associated with exercise. In addition, other findings from this laboratory and others have implicated alterations in this same brain region in spontaneously hypertensive rats as contributing factors of the elevated levels of arterial pressure in hypertension. Several studies have revealed a gamma-amino-butyric acid (GABAergic) deficiency in the caudal hypothalamus of spontaneously hypertensive rats that contributes to the tonic disinhibition and overactivity of this pressor region. Because chronic exercise is able to increase cardiovascular health in the hypertensive rat, we hypothesized that exercise-induced caudal hypothalamic plasticity partially underlies the beneficial effects of physical activity. In this review we discuss initial findings from this lab that support this hypothesis. Our experiments demonstrate that chronic exercise alters gene expression and neuronal activity in the caudal hypothalamus of the spontaneously hypertensive rat. These findings describe a potential mechanism by which chronic exercise lowers blood pressure in the hypertensive individual.

Evaluation of commercially available assays of neopterin and beta 2-microglobulin for the assessment of disease progression in FIV-infected cats.

Serum or plasma samples from cats at different stages of feline immunodeficiency (FIV) infection and from uninfected cats were tested using immunoassays designed to detect human neopterin and beta 2-microglobulin (beta 2M). The results obtained from the anti-human neopterin assay did not correlate with infection status, time post-infection, fCD4 count or clinical picture. Feline samples gave negative results in the anti-human beta 2M assay. The assay kits used in this study are not suitable for the determination of the effect of FIV infection on immune activation markers in the cat.

A recombinant feline immunodeficiency virus envelope fusion protein stimulates peripheral blood lymphocytes from naive cats to proliferate in vitro.

A region of feline immunodeficiency virus (FIV)/Glasgow-8 external envelope glycoprotein (env) incorporating the third and fourth variable regions (V3/V4) was cloned, inserted into the pGEX vector and expressed in Escherichia coli to yield milligram quantities of the recombinant polypeptide as a fusion protein with glutathione S-transferase. The fusion protein V3/V4GST was used in lymphocyte proliferation assays, where it consistently caused peripheral blood lymphocytes from naive cats to proliferate in a dose-dependent manner. Other FIV fusion proteins produced under identical conditions (V5GST and p24GST) and glutathione S-transferase alone did not cause proliferation in this system. The monoclonal antibody vpg15, which has been shown to block infection of susceptible cells in vitro, did not decrease the response to V3/V4GST. Human peripheral blood lymphocytes did not proliferate in response to V3/V4GST.

Feline immunodeficiency virus (FIV)-associated lymphoma: a potential role for immune dysfunction in tumourigenesis.

To determine the potential role of immune dysfunction in feline immunodeficiency virus (FIV)-associated lymphomagenesis, we present the results of immunological monitoring during the chronic phase of experimental FIV infection in two cats which subsequently developed lymphoma. In one cat, C1, cell-mediated immunity was depressed throughout the monitoring period but particularly from 125-200 weeks post-infection (pi), when this cat demonstrated profoundly impaired lymphocyte blastogenesis and markedly increased interleukin-1 (IL-1) production compared to age-matched, uninfected control cats. Lymphocyte function in the other cat, C2, was preserved to a greater degree. Alterations in the levels of immunoglobulin isotypes M, A and G in CD4+-, CD8+- and CD21+-lymphocyte sub-sets were demonstrated in both cats. Southern blot analysis revealed the presence of integrated FIV-provirus in tumour DNA from C2 but not C1 indicating a possible direct role for the virus in the former case only. In this study we have characterised, for the first time, the FIV-induced immune dysfunction in cats which developed lymphoma, demonstrating potential indirect mechanisms of tumourigenesis.

Peripheral vestibular disease associated with cryptococcosis in three cats.

Peripheral vestibular disease referable to otitis media/interna was the main reason for presentation in three cats with cryptococcosis. In two cats, Cryptococcus neoformans var neoformans was isolated from the tympanic bulla. In the remaining cat, otitis media/interna was considered to be secondary to occlusion of the auditory tube by a nasopharyngeal granuloma associated with a C neoformans var gattii infection. This report emphasises the importance of maintaining an index of suspicion for a fungal aetiology in cats with signs of otitis media/interna, particularly in countries with a high prevalence of cryptococcosis. The presence of C neoformans may be overlooked with potentially fatal consequences where only standard methods for bacterial isolation are used to examine samples obtained from the middle ear.