Epidemiological insights into the burden of feline upper respiratory tract infections in Queensland RSPCA shelters.

INTRODUCTION: Feline upper respiratory tract infection (FURTI) is a severe problem in animal shelters where there is high turnover of populations and compromised immunity. This retrospective cohort study explores associations of potential animal-based and environmental-based factors with the risk of FURTI, where a previously modelled infection classification is used as the outcome of interest. The study type is a retrospective cohort and the measures of association include Odds Ratios and conditional predictions. OBJECTIVES: To gain epidemiological insights into variation in FURTI using retrospective data from one of Australia's leading animal shelters. METHODS: We stratified FURTI by admission and environmental variables. Predicted infection status, obtained using a machine-learning classifier trained on clinical text (accuracy 0.95 [CI 0.92, 0.97]), was used as the outcome of interest. Prior assumptions were represented by a causal framework or a direct acyclic graph (DAG), which informed creation of multiple Bernoulli models with an observational and prior component. RESULTS: We analysed 43,431 feline entries over 8 years. Males were 1.24 (95% CI 1.19 to 1.31) times more likely than females to be classified as positive, while already desexed animals were only 0.68 (95% CI 0.60 to 0.72) as likely to be classified as positive compared to those not desexed on entry. Cats (>4 months) were twice as likely (95% CI 1.91 to 2.09) as kittens (0-4 months) to be classified positive. Animals entering the shelter as seized by the inspectorate (n = 415) were more likely to be classified positive compared to animals from other sources. Predicted infection probability increased in winter and showed a linear pattern with how full the shelter was. CONCLUSION: This study estimates the association between animal and environmental variables of interest and FURTI classification status, thus better interpreting the distribution of disease as predicted by a previously uninterpretable model. This analysis gives much needed insight into the types of changes in an animal's environment that can impact final animal outcomes.

Current evidence for non-pharmaceutical, non-surgical treatments of canine osteoarthritis.

Osteoarthritis is a progressive degenerative disease process that affects a significant proportion of the canine population, impacting these animals' quality of life. Currently, there is no cure and treatment consists of managing the clinical signs of pain and reduced mobility. There are many treatments for canine osteoarthritis and in this review we discuss the evidence base behind non-pharmaceutical, non-surgical treatments of this disease. These treatments include weight management, nutraceuticals, acupuncture, physiotherapies such as therapeutic exercise, hydrotherapy as well as other therapeutic modalities including photobiomodulation therapy, electromagnetic field therapy and others.

The impact of COVID-19 public health measures on attendance and overdose at supervised injecting facilities in Australia.

OBJECTIVES: The COVID-19 pandemic disrupted service provision of harm reduction and drug treatment services for people who inject drugs in many countries. The two supervised injecting facilities (SIFs) in Sydney and Melbourne were differentially impacted by the pandemic, requiring local procedural changes in each service. We aimed to examine the impact of pandemic responses (including restrictions on movement, known as 'lockdowns') on service use and key parameters such as client reports of drug injected and recorded overdose rates. STUDY DESIGN: Time series analysis of weekly client visits and monthly overdoses occurring at each service. METHODS: Administrative client data from the two SIFs (Sydney data from 1 January 2018 to 30 April 2022; Melbourne data from 1 July 2018 to 30 April 2022) were examined using interrupted time series analyses with lockdown dates in each state entered as interruption terms. We analysed weekly SIF visits overall and by drug type, and monthly rates of opioid overdose at each service. RESULTS: Lockdowns resulted in decreased visits to both services. The number of weekly client visits decreased during the first national lockdown for both the Sydney (trend change = -57.9; 95% CI [-109.4, -6.4]) and Melbourne SIF (near sig trend change = -54.8 [-110.8, 1.05]). Trends in visit numbers increased after lockdowns were lifted in each city; however, visits in Sydney have not returned to the numbers recorded prior to the pandemic. Visits to the Melbourne SIF related to heroin use declined at each lockdown (trend 1 = -42.7 [-81.5, -3.9]; trend 2 = -56.1 [-94.6, -17.7]; trend 3 = -33.8 [-67.4, -0.2]); heroin visits to the Sydney SIF declined during the first lockdown and remained low (trend = -55.6 [-82.8, -28.3]). Methamphetamine visits to the Sydney SIF fluctuated, surpassing heroin visits at several timepoints. Rates of monthly opioid overdoses at both services declined immediately following the start of the first lockdown (Sydney = -16.6 [-26.1, -6.8]; Melbourne = -6.4 [-8.7, -4.1]), with increasing trends recorded at the end of the final lockdown in each jurisdiction (Sydney = 2.8 [0.6, 5.0]; Melbourne = 1.3 [0.72, 3.2]). CONCLUSIONS: Public health restrictions related to the COVID-19 pandemic were associated with reduced client visits to, and overdoses in, Australian SIFs. Variations were noted in the drugs injected, likely reflecting changes in local drug markets. Shifts to other drugs during these periods were evident: methamphetamine in Sydney; co-injection of heroin and diphenhydramine in Melbourne.

An update on mobility assessment of dogs with musculoskeletal disease.

Mobility impairments associated with musculoskeletal diseases, such as osteoarthritis and degenerative joint disease, affect approximately 200,000 dogs annually and pose a notable challenge to canine health and welfare. Osteoarthritis causes the remodelling of synovial joints, alongside inflammation and impaired mechanical function which can be extremely debilitating. Secondary osteoarthritis commonly affects dogs and can be exacerbated by previous joint abnormalities, such as patellar luxation or cranial cruciate ligament rupture. Although musculoskeletal diseases can affect dogs of any age, the early subtle signs of gait abnormalities are perhaps missed by owners, thus, dogs may be in the latter stages of osteoarthritis progression when they are presented to veterinarians. Dogs showing subtle signs of gait abnormalities must be presented to veterinary practices for acute diagnosis to prevent long-term deterioration. Musculoskeletal diseases, such as osteoarthritis and degenerative joint disease, are commonly diagnosed via visible radiographic changes. However, veterinarians can use a combination of subjective and objective clinical scoring systems, such as clinical metrology instruments and gait assessment in conjunction with radiography to aid their diagnosis and longitudinal monitoring of musculoskeletal diseases. These scoring systems may be more sensitive to earlier signs of mobility impairments in dogs, ultimately, promoting increased canine health and welfare by enabling pain reduction, improvement of muscle strength and preservation of joint function. Current canine mobility scoring systems available to veterinarians will be discussed in turn throughout this review for implementation into clinical practice.

Management of vagus nerve stimulation therapy in the peri-operative period: Guidelines from the Association of Anaesthetists: Guidelines from the Association of Anaesthetists.

Vagus nerve stimulation is a well-established treatment option for patients with drug-resistant epilepsy and has an expanding range of other clinical indications. Side effects of vagus nerve stimulation therapy include: cough; voice changes; vocal cord adduction; rarely, obstructive sleep apnoea; and arrhythmia. Patients with implanted vagus nerve stimulation devices may present for unrelated surgery and critical care to clinicians who are unfamiliar with their function and safe management. These guidelines have been formulated by multidisciplinary consensus based on case reports, case series and expert opinion to support clinicians in the management of patients with these devices. The aim is to provide specific guidance on the management of vagus nerve stimulation devices in the following scenarios: the peri-operative period; peripartum period; during critical illness; and in the MRI suite. Patients should be aware of the importance of carrying their personal vagus nerve stimulation device magnet with them at all times to facilitate urgent device deactivation if necessary. We advise that it is generally safer to formally deactivate vagus nerve stimulation devices before general and spinal anaesthesia. During periods of critical illness associated with haemodynamic instability, we also advise cessation of vagus nerve stimulation and early consultation with neurology services.

Discovery of a functionally selective ghrelin receptor (GHSR1a) ligand for modulating brain dopamine.

SignificanceThe modulation of growth hormone secretagogue receptor-1a (GHSR1a) signaling is a promising strategy for treating brain conditions of metabolism, aging, and addiction. GHSR1a activation results in pleiotropic physiological outcomes through distinct and pharmacologically separable G protein- and ß-arrestin (ßarr)-dependent signaling pathways. Thus, pathway-selective modulation can enable improved pharmacotherapeutics that can promote therapeutic efficacy while mitigating side effects. Here, we describe the discovery of a brain-penetrant small molecule, N8279 (NCATS-SM8864), that biases GHSR1a conformations toward Gαq activation and reduces aberrant dopaminergic behavior in mice. N8279 represents a promising chemical scaffold to advance the development of better treatments for GHSR1a-related brain disorders involving the pathological dysregulation of dopamine.

Haemoprotozoa in wild short-beaked echidnas (Tachyglossus aculeatus).

The occurrence and clinical significance of the protozoal parasite reported as Hepatozoon tachyglossi in wild short-beaked echidnas (Tachyglossis aculeatus) have long been uncertain, as has its potential as a prognostic indicator. This retrospective survey of free-ranging short-beaked echidnas admitted to a wildlife hospital used morphological evidence to identify a H. tachyglossi prevalence of 56%, with parasitaemias affecting 0%-36% of monocytes. There was no statistical association between H. tachyglossi intensity and clinical status (P-value = 0.12; 95% confidence interval = 0.1 to 1.3), nor between the presence of H. tachyglossi and age, reason for admission, outcome, season or location. Piroplasms, presumed to be Theileria tachyglossi, were concurrently identified in the erythrocytes of 88% of short-beaked echidnas with no association between age, outcome, season or location, but a statistical association with the location where the animal was found (either on a road, airport runway, exposed urban area, or entangled). Given the current results, intracellular parasitism due to H. tachyglossi may be considered as an incidental finding on haematologic examination of short-beaked echidnas and is likely not an effective prognostic indicator. Further research using molecular tools is required to resolve the uncertain identity of H. tachyglossi which has been based on morphologic characteristics alone.

Tick paralysis in Australian birds caused by Ixodes holocyclus.

Tick paralysis is an uncommon cause of neuromuscular paralysis affecting 0.12% of wild birds presented to Currumbin Wildlife Sanctuary, Queensland, with a strong seasonal predilection towards spring and summer. Clinical signs and progression of paralysis showed similarities to companion animals and were consistent across 20 species. Tick location, number of engorged ticks and number of clinical signs did not affect the outcome; however, all mortalities occurred within 4 days of admission. Treatment with canine-derived tick antiserum resulted in clinical improvement within 24 h and a recovery rate of 73%. Average time to resolution of clinical signs was 4.3 days, with juvenile birds recovering more quickly than adults. The treatment and release of wild birds affected by tick paralysis are both achievable and rewarding, further research is required to establish treatment guidelines in birds.

Chemical structure, anti-inflammatory and antinociceptive activities of a sulfated polysaccharide from Gracilaria intermedia algae.

The present work aimed at carrying out the isolation and biochemical characterization of a sulfated polysaccharide fraction (PLS) from the marine algae Gracilaria intermedia and investigating its anti-inflammatory and antinociceptive potential. PLS was obtained through enzymatic digestion with papain and analyzed by means of gel permeation chromatography and Nuclear Magnetic Resonance to 1H and 13C. In order to evaluate the potential of anti-inflammatory action of PLS, we performed paw edema induced by carrageenan, dextran, compound 48/80, histamine and serotonin. In addition, we also measured the concentration of myeloperoxidase, cytokines, the count of inflammatory cells and performed tests of the nociception. The PLS isolated was of high purity and free of contaminants such as proteins, and had molecular weight of 410 kDa. The same macromolecule was able to decrease the paw edema induced by all inflammatory agents (P < 0.05), myeloperoxidase (MPO) activity, neutrophil migration and IL-1ß levels. It also decreased acetic acid-induced writhing (P < 0.05) and formalin-induced paw licking time (P < 0.05), but no in hot plate test. In summary, the PLS decreased the inflammatory response by reducing neutrophil migration and modulating IL-1ß production and antinociceptive effects by a peripheral mechanism dependent on the down-modulation of the inflammatory mediators.

Genetic analysis of porcine circovirus type 2 (PCV2) in Queensland, Australia.

OBJECTIVE: To determine the current porcine circovirus type 2 (PCV2) genotypes circulating in pigs in Queensland (QLD). METHODS: The PCV2 infection status of pigs was determined by real-time PCR testing of 210 lymph nodes and 30 serum samples derived from 45 QLD farms. PCV2-positive samples from 22 pigs from 15 farms were subjected to conventional polymerase chain reaction (PCR) and sequencing of the full PCV2 genome. Phylogenetic analysis of 17 of these sequences in relation to published PCV2 sequences was then performed, and the genotypes were compared. RESULTS: PCV2 DNA was detected in 95 lymph nodes and 15 serum samples. Phylogenetic analysis of 17 PCV2 sequences demonstrated that seven belonged to genotype PCV2b, two to PCV2d, one to PCV2f and seven to an "intermediate group" that clustered with PCV2d on the full genome analysis. CONCLUSION: This work confirms earlier studies reporting the presence of PCV2b in Australia. It is the first study to report that PCV2d and PCV2f are also present in this country. PCV2d is currently a fast-spreading genotype globally, with reported high virulence. The potential implications of these findings with respect to pathogenicity and vaccine efficacy require further investigation.

Molecular p-doping in organic liquid crystalline semiconductors: influence of the charge transfer complex on the properties of mesophase and bulk charge transport.

We explore the molecular nature of doping in organic semiconductors (OSCs) by employing a liquid crystalline organic semiconductor based on phenyl naphthalene as a model. The mesophase nature of composites that include a charge transfer complex (CTC) between the OSC (8-PNP-O12) and an electron acceptor (F4TCNQ) has been investigated by means of differential scanning calorimetry, polarized optical microscopy and X-ray scattering. Optical and vibrational spectroscopies allow us to explore the characteristics and the amount of charge transfer in the CTC and expose some properties that appear only in the complexed state. We have found this system to exhibit partial charge transfer, which manifests itself in all the phase states of the host 8-PNP-O12, as well as in solution. Due to the lowering of molecular symmetry as a result of the charge transfer, one of the previously IR-only vibrational bands of the nitrile group is found to be now active in the Raman spectrum. We have also made an attempt to further investigate the influence of dopant introduction on the bulk hole mobility of 8-PNP-O12. It is found that the presence of the CTC promotes the hole transport in the Smectic B mesophase, however it seems to have a somewhat negative influence in the less ordered smectic A mesophase. This work aims to establish the link between the inevitable change of molecular geometry that occurs on charge transfer with the results obtained by spectroscopic techniques and electronic charge carrier mobility measurements.

A new look at the origins of gibbon ape leukemia virus.

Is the origin of gibbon ape leukemia virus (GALV) human after all? When GALV was discovered and found to cause neoplastic disease in gibbons, it stimulated a great deal of research including investigations into the origins of this virus. A number of publications have suggested that the GALV progenitor was a retrovirus present in one of several species of South East Asian rodents that had close contact with captive gibbons. However, there are no published retroviral sequences from any South East Asian species to support this view. Here we present an alternative hypothesis that the origin of GALV is a virus closely related to Melomys burtoni retrovirus, and that this virus infected human patients in Papua New Guinea from whom biological material was obtained or in some way contaminated these samples. This material we propose contained infectious MbRV-related virus that was then unwittingly introduced into gibbons which subsequently developed GALV infections.

Novel Regulators of Hemodynamics in the Pregnant Uterus.

The uterus is a highly dynamic organ, undergoing dramatic physiological changes during normal cyclicity and pregnancy. Many of these changes involve remodeling of the uterine vasculature in order to provide oxygen and nutrients to the developing embryo/fetus. Vasculogenesis, angiogenesis, vasodilation/vasoconstriction, and vascular permeability are coordinated by a vast network of autocrine, paracrine, and endocrine-signaling factors that derive from a number of cellular sources at the maternal:fetal interface, as well as from tissue outside the uterus. In this chapter, the dynamic changes that occur in uterine vasculature during pregnancy are described, and some of the hemodynamic regulatory factors are reviewed. These include uterine natural killer cells, sex steroid hormones, the calcitonin gene-related peptide family, angiopoietins, sphingolipids, and the renin-angiotensin system. Aberrancies in these factors are associated with disorders of uterine vascular remodeling, leading to conditions such as early pregnancy loss, preeclampsia, uterine hemorrhage, and intrauterine growth restriction. In addition, we introduce the role of the mas-related gene family in angiotensin signaling and endothelial function during pregnancy. Finally, this chapter introduces the novel concept that in addition to remodeling the vasculature to bring oxygenated maternal blood to the embryo, the gravid uterus synthesizes its own hemoglobin. Overall, this chapter provides an overview of the regulators of uterine vascular remodeling and hemodynamics during pregnancy and pregnancy-associated pathologies.

Anti-diarrhoeal therapeutic potential and safety assessment of sulphated polysaccharide fraction from Gracilaria intermedia seaweed in mice.

Sulphated polysaccharides extracted from algae have been extensively studied for their diverse biological activities. Thus, the purpose of this study was to evaluate the chemical composition, the anti-diarrhoeal effect and acute toxicity of a sulphated polysaccharide fraction obtained from Gracilaria intermedia (SP-Gi). Initially, the FT-IR of SP-Gi revealed to be an agaran with sulphation at C-6 of the l-galactosyl residues. The anti-diarrhoeal activity of SP-Gi was evaluated in a castor oil-induced diarrhoea model. The effects of SP-Gi on enteropooling, Na +-K +-ATPase activity, gastrointestinal transit, and gastric emptying were then examined. Subsequently, the effect of SP-Gi on diarrhoea induced by cholera toxin (CT) and Escherichia coli was examined. In addition, an acute toxicity test was conducted in accordance with OECD guideline 423. Pre-treatment with SP-Gi reduces the total faeces, total diarrhoeal faeces, and enteropooling. SP-Gi (30mg/kg p.o.) increased Na+/K+-ATPase activity and reduced gastrointestinal transit through anticholinergic mechanisms. ELISA demonstrated that SP-Gi can interact with GM1 receptors and CT. SP-Gi reduced diarrhoea induced by E. coli and prevented weight loss in the animals. Moreover, SP-Gi did not induce any toxicity signs. These results suggest that SP-Gi is a possible candidate for the treatment of diarrhoeal illnesses.

Expression of CD33 is a predictive factor for effect of gemtuzumab ozogamicin at different doses in adult acute myeloid leukaemia.

It remains unclear in adult acute myeloid leukaemia (AML) whether leukaemic expression of CD33, the target antigen for gemtuzumab ozogamicin (GO), adds prognostic information on GO effectiveness at different doses. CD33 expression quantified in 1583 patients recruited to UK-NCRI-AML17 (younger adults) and UK-NCRI-AML16 (older adults) trials was correlated with clinical outcomes and benefit from GO including a dose randomisation. CD33 expression associated with genetic subgroups, including lower levels in both adverse karyotype and core-binding factor (CBF)-AML, but was not independently prognostic. When comparing GO versus no GO (n=393, CBF-AMLs excluded) by stratified subgroup-adjusted analysis, patients with lowest quartile (Q1) %CD33-positivity had no benefit from GO (relapse risk, HR 2.41 (1.27-4.56), P=0.009 for trend; overall survival, HR 1.52 (0.92-2.52)). However, from the dose randomisation (NCRI-AML17, n=464, CBF-AMLs included), 6 mg/m2 GO only had a relapse benefit without increased early mortality in CD33-low (Q1) patients (relapse risk HR 0.64 (0.36-1.12) versus 1.70 (0.99-2.92) for CD33-high, P=0.007 for trend). Thus CD33 expression is a predictive factor for GO effect in adult AML; although GO does not appear to benefit the non-CBF AML patients with lowest CD33 expression a higher GO dose may be more effective for CD33-low but not CD33-high younger adults.

Sulfated polysaccharide fraction from marine algae Solieria filiformis: Structural characterization, gastroprotective and antioxidant effects.

A sulfated polysaccharide (SFP) fraction from the marine alga Solieria filiformis was extracted and submitted to microanalysis, molar mass estimation and spectroscopic analysis. We evaluated its gastroprotective potential in vivo in an ethanol-induced gastric damage model and its in vitro antioxidant properties (DPPH, chelating ferrous ability and total antioxidant capacity). Its chemical composition revealed to be essentially an iota-carrageenan with a molar mass of 210.9kDa and high degree of substitution for sulfate groups (1.08). In vivo, SFP significantly (P<0.05) reduced, in a dose dependent manner, the ethanol-induced gastric damage. SFP prevents glutathione consume and increase of malondialdehyde and hemoglobin levels. SFP presented an IC50 of 1.77mg/mL in scavenging DPPH. The chelating ferrous ability was 38.98%, and the total antioxidant capacity was 2.01mg/mL. Thus, SFP prevents the development of ethanol-induced gastric damage by reducing oxidative stress in vivo and possesses relevant antioxidant activity in vitro.

Molecular and morphological description of Haemoproteus (Parahaemoproteus) bukaka (species nova), a haemosporidian associated with the strictly Australo-Papuan host subfamily Cracticinae.

Linking morphological studies with molecular phylogeny is important to understanding cryptic speciation and the evolution of host-parasite relationships. Haemosporidian parasites of the Australo-Papuan bird family Artamidae are relatively unstudied. Only one parasite species from the subfamily Cracticinae has been described, and this was based solely on morphological description. This is despite many Cracticinae species being easily observed and abundant over large ranges and in close proximity to human populations. We used morphological and molecular methods to describe a new Haemoproteus species (H. bukaka sp. nov.) from an endemic Butcherbird host (Cracticus louisiadensis) in a relatively unstudied insular area of high avian endemism (Papua New Guinea's Louisiade Archipelago). Phylogenetic reconstructions using parasite cyt-b gene sequences placed the proposed Haemoproteus bukaka sp. nov. close to other host-specialist Haemoproteus species that infect meliphagid honeyeater hosts in the region, e.g. H. ptilotis. Distinct morphological characters of this haemosporidian include macrogametocytes with characteristic large vacuoles opposing a subterminal nucleus on the host cell envelope. Among 27 sampled individuals, prevalence of H. bukaka sp.nov. was high (74 % infection rate) but strongly variable across four islands in the archipelago (ranging from 0 to 100 % prevalence). Parasitaemia levels were low across all infected individuals (0.1-0.6 %). We suspect host density may play a role in maintaining high prevalence given the close proximity and similar physical environments across islands. The findings are discussed in the context of the host genus Cracticus and theory relating to parasite-host evolution and its conservation implications in Papua New Guinea.

Current practices for treatment of respiratory syncytial virus and other non-influenza respiratory viruses in high-risk patient populations: a survey of institutions in the Midwestern Respiratory Virus Collaborative.

BACKGROUND: The optimal treatment for respiratory syncytial virus (RSV) infection in adult immunocompromised patients is unknown. We assessed the management of RSV and other non-influenza respiratory viruses in Midwestern transplant centers. METHODS: A survey assessing strategies for RSV and other non-influenza respiratory viral infections was sent to 13 centers. RESULTS: Multiplex polymerase chain reaction assay was used for diagnosis in 11/12 centers. Eight of 12 centers used inhaled ribavirin (RBV) in some patient populations. Barriers included cost, safety, lack of evidence, and inconvenience. Six of 12 used intravenous immunoglobulin (IVIG), mostly in combination with RBV. Inhaled RBV was used more than oral, and in the post-stem cell transplant population, patients with lower respiratory tract infection (LRTI), graft-versus-host disease, and more recent transplantation were treated at higher rates. Ten centers had experience with lung transplant patients; all used either oral or inhaled RBV for LRTI, 6/10 treated upper respiratory tract infection (URTI). No center treated non-lung solid organ transplant (SOT) recipients with URTI; 7/11 would use oral or inhaled RBV in the same group with LRTI. Patients with hematologic malignancy without hematopoietic stem cell transplantation were treated with RBV at a similar frequency to non-lung SOT recipients. Three of 12 centers, in severe cases, treated parainfluenza and metapneumovirus, and 1/12 treated coronavirus. CONCLUSIONS: Treatment of RSV in immunocompromised patients varied greatly. While most centers treat LRTI, treatment of URTI was variable. No consensus was found regarding the use of oral versus inhaled RBV, or the use of IVIG. The presence of such heterogeneity demonstrates the need for further studies defining optimal treatment of RSV in immunocompromised hosts.

The efficacy of a sulphated polysaccharide fraction from Hypnea musciformis against diarrhea in rodents.

Seaweeds are sources of diverse bioactive compounds, such as sulphated polysaccharides. This study was designed to evaluate the chemical composition and anti-diarrheal activity of a fraction of sulphated polysaccharide (PLS) obtained from the red seaweed Hypnea musciformis in different animal models, and to elucidate the underlying mechanisms. PLS was obtained by aqueous extraction, with a yield of 31.8% of the seaweed dry weight. The total carbohydrate content accounted for 99% of the sample. The sulfate content of the polysaccharide was 5.08% and the percentage of carbon was 25.98%. Pretreatment with all doses of PLS inhibited castor oil-induced diarrhea, with reduction of the total amount of stool, diarrheal stools, and the severity of diarrhea. PLS (90 mg/Kg) decreased castor oil- and PGE2-induced enteropooling. In addition, PLS (90 mg/Kg) increased the Na(+)/K(+)-ATPase activity in the small intestine and reduced gastrointestinal transit, possibly via activation of cholinergic receptors. Interestingly, the cholera toxin-induced fluid secretion and Cl(-) ion levels decreased in the intestinal contents of the animals pretreated with PLS (90 mg/kg), probably via reduction of toxin-GM1 receptor binding. In conclusion, PLS exerts anti-diarrheal activity by increasing Na(+)/K(+)-ATPase activity, inhibiting gastrointestinal motility, and blocking the toxin-GM1 receptor binding.

Spontaneous liquid crystal and ferromagnetic ordering of colloidal magnetic nanoplates.

Ferrofluids are familiar as colloidal suspensions of ferromagnetic nanoparticles in aqueous or organic solvents. The dispersed particles are randomly oriented but their moments become aligned if a magnetic field is applied, producing a variety of exotic and useful magnetomechanical effects. A longstanding interest and challenge has been to make such suspensions macroscopically ferromagnetic, that is having uniform magnetic alignment in the absence of a field. Here we report a fluid suspension of magnetic nanoplates that spontaneously aligns into an equilibrium nematic liquid crystal phase that is also macroscopically ferromagnetic. Its zero-field magnetization produces distinctive magnetic self-interaction effects, including liquid crystal textures of fluid block domains arranged in closed flux loops, and makes this phase highly sensitive, with it dramatically changing shape even in the Earth's magnetic field.