Effect of Hypotension and Dobutamine on Gastrointestinal Microcirculations of Healthy, Anesthetized Horses

Horses undergoing abdominal exploratory surgery are at risk of hypotension and hypoperfusion. Normal mean arterial pressure is used as a surrogate for adequate tissue perfusion. However, measures of systemic circulation may not be reflective of microcirculation. This study measured the mean arterial pressure, cardiac index, lactate, and four microcirculatory indices in six healthy, anesthetized adult horses undergoing elective laparotomies. The microcirculatory parameters were measured at three different sites along the gastrointestinal tract (oral mucosa, colonic serosa, and rectal mucosa) with dark-field microscopy. All macro- and microcirculatory parameters were obtained when the horses were normotensive, hypotensive, and when normotension returned following treatment with dobutamine. Hypotension was induced with increases in inhaled isoflurane. The horses successfully induced into hypotension did not demonstrate consistent, expected changes in systemic perfusion or microvascular perfusion parameters at any of the three measured gastrointestinal sites. Normotension was successfully restored with the use of dobutamine, while the systemic perfusion and microvascular perfusion parameters remained relatively unchanged. These findings suggest that the use of mean arterial pressure to make clinical decisions regarding perfusion may or may not be accurate.

Establishing consensus on the best ways to educate children about animal welfare and prevent harm: An online Delphi study

Many animal welfare organisations deliver education programmes for children and young people, or design materials for schoolteachers to use. However, few of these are scientifically evaluated, making it difficult for those working in this field to establish with any certainty the degree of success of their own programmes, or learn from others. There has been no guidance specifically tailored to the development and evaluation of animal welfare education interventions. Accordingly, a three-stage online Delphi study was designed to unearth the expertise of professionals working in this field and identify degree of consensus on various aspects of the intervention process: design, implementation and evaluation. Thirty-one experts participated in Round 1, representing eleven of 13 organisations in the Scottish Animal Welfare Education Forum (SAWEF), and eleven of 23 members of the wider UK-based Animal Welfare Education Alliance (AWEA). Seven further professionals participated, including four based in Canada or the US. Eighty-four percent of the original sample participated in Round 2, where a high level of consensus was apparent. However, the study also revealed areas of ambiguity (determining priorities, the need for intervention structure and degree of success). Tensions were also evident with respect to terminology (especially around cruelty and cruelty prevention), and the common goal for animal welfare to be part of school curricula. Findings were used to develop a web-based framework and toolkit to enable practitioners to follow evidence-based guidance. This should enable organisations to maximise the quality and effectiveness of their interventions for children and young people.

The challenges and future development of animal welfare education in the UK

At present, UK schools are not required to teach children about animal welfare. This undoubtedly contributes to widespread deficien- cies in knowledge, and misconceptions about animals needs, likes, and dislikes. Aware of the issues at hand, animal welfare organi- sations create their own materials for teachers to use, and/or deliver educational programmes directly to children and young people. As the design, content, processes and outcomes associated with these interventions are rarely documented publicly or systematically evaluated, there is little evidence to guide the development of animal welfare education. A three-stage online Delphi study was used to identify who current interventions target, what delivery methods are being used, and how expert practitioners describe priorities and challenges in the field. Thirty-one experts participated in Round 1, with 84% of the sample (n = 26) also taking part in Round2. Qualitative analysis revealed passionate accounts about the far-reaching potential of educating children about animals. However, we also identified ambiguities and tensions that could thwart the future development of effective animal welfare education. Alongside the production of a web-based framework and evidence-based toolkit to support practitioners, findings will be used to encourage animal welfare professionals to work towards producing shared terminology, definitions, and outcomes frameworks; focusing on positive education and the idea of harm as opposed to cruelty. This should facilitate collaboration with schoolteachers and education policy-makers to assess the ways in which animal welfare might be successfully incorporated within formal education in the future. These data suggest many potential avenues for inclusion, although a holistic approach emphasising the links between humans, animals and the environment, within the context of young peoples recent activism and contemporary health, societal and environmental issues, may be most successful.

Socioeconomic inequalities and the equity impact of population-level interventions for adolescent health: an overview of systematic reviews

OBJECTIVES

Despite robust evidence on health inequalities in adulthood, less attention has been paid to inequalities in adolescence. The aim of this overview was to examine systematic review (SR) evidence on the equity impact of population-level interventions intended to improve health, happiness and wellbeing for adolescents.

STUDY DESIGN

An overview (review of systematic reviews).

METHODS

Eleven electronic databases were systematically searched to identify SRs of population-level interventions for adolescent health. A secondary data analysis of socioeconomic inequality was conducted to identify whether SRs reported on primary studies in terms of disadvantage, by measures of socioeconomic status (SES) and by differential effects.

RESULTS

35,310 review titles were screened; 566 full texts were retrieved and 140 SRs met the predefined selection criteria. Differential intervention effects were considered in 42/140 (30%) SRs, 18/140 (13%) reported primary studies using an SES measure and 16/140 (11%) explicitly reported differential effects. 15/140 SRs (11%) explicitly focused on socioeconomic inequalities; of these 4/15 reported differential intervention effects in more detail, 7/15 concluded there was insufficient primary evidence to identify the impact of interventions on socioeconomic inequalities and 4/15 planned to examine differential effects by SES, but this was not reported further.

CONCLUSIONS

Our overview identifies that there is limited SR evidence on the equity impact of population-level interventions for adolescent health. Strengthening the evidence on whether interventions narrow or widen inequalities for adolescents must be a priority for public health research.

Ruminal impaction in a miniature zebu steer

An approximately one-year-old miniature zebu steer was examined for lethargy, anorexia and decreased faecal output of one day’s duration. Based on the steer’s history of malnourishment, physical examination and abdominal radiographic images, ruminal impaction was discussed as the top differential diagnosis. Exploratory flank laparotomy and rumenotomy demonstrated severe ruminal impaction of primarily hickory nuts with additional fibrous feed material, sand and two small, blunt, metallic objects. These materials were manually removed, and the rumen and reticulum were thoroughly lavaged. The steer recovered well from general anaesthesia and was treated with repeated orogastric transfaunation postoperatively. The steer did well for the remainder of his hospitalisation, was returned to a normal diet, resumed passage of normal faeces and was discharged three days postoperatively.

Comparison of the oral and rectal mucosal and colonic serosal microcirculations of healthy, anesthetized horses

The objectives of the study were to: i) determine baseline microvascular perfusion indices (MPI) and assess their repeatability in healthy horses under general anesthesia, and ii) compare the MPIs of 3 microvascular beds (oral mucosa, colonic serosa, and rectal mucosa). Healthy adult horses were anesthetized and sidestream dark field microscopy was used to collect video loops of the oral mucosa, rectal mucosa, and colonic serosa under normotensive conditions without cardiovascular support drugs; videos were later analyzed to produce MPIs. Baseline MPI values were determined for each site, which included the total vessel density (TVD), perfused vessel density (PVD), portion perfused vessels (PPV), and microcirculatory flow index (MFI). Differences in MPIs between microvascular beds were not statistically significant. Repeatability of the measurements varied for each MPI. In particular, the site of sampling had a profound effect on the repeatability of the PPV measurements and should be considered in future studies.

Internal fixation of fractured ribs in neonatal foals with nylon cable tie using a modified technique

Nylon cable tie has been shown to be an effective and economical method for fixing fractured ribs in the neonatal foal. This article describes a modification of the previously described technique. Under general anesthesia, the fractured ribs were exposed and a hole was drilled in the dorsal and ventral fragments. The fracture was not reduced, leaving the fragments overriding each other. The nylon cable tie was passed through the hole in the dorsal fragment from the external surface of the rib. The free end of the cable tie was then passed through the hole in the ventral fragment from the external surface of the rib and the tie was tightened. This technique was used in 4 neonatal foals with no complications. The modification of the original technique represents a method to minimize soft tissue trauma, implant failure, and complications.

Children and young people's conceptualizations of depression: a systematic review and narrative meta-synthesis

BACKGROUND

There is an increasing research interest in conceptualizations of mental illness, examined in association with help-seeking, stigma and treatment preferences. A recent focus on young people's concepts has been identified, with depression being one of the most examined conditions.

METHODS

The purpose of this systematic review is to synthesize evidence on children and adolescents' conceptualizations of depression, adopting the model of illness representations. The review further aims to examine developmental trends, gender differences and the role of experience. A systematic review and narrative meta-synthesis were conducted, reviewing 36 studies identified through a systematic search of six databases in March 2016.

RESULTS

Thirty-six quantitative and qualitative studies were included. Half of the young people are able to recognize depression, and recognition increases when symptoms are more severe (e.g. suicidality). Young people are able to name a variety of causes for depression. Mental health professionals are considered the appropriate source of help by half of the young people, followed by family and peers. However, stigma constitutes a major barrier to help-seeking. There are developmental trends and gender differences in young people's conceptualization of depression, while experience with depression is associated with a broader conceptualization.

CONCLUSIONS

Young people's concepts of depression resemble aspects of adult conceptualizations, however are sometimes incomplete. Further research on younger children and clinical populations is needed. Research on young people's conceptualizations informs both clinical practice and mental health literacy interventions.

Epithelial cell shedding and barrier function: a matter of life and death at the small intestinal villus tip

The intestinal epithelium is a critical component of the gut barrier. Composed of a single layer of intestinal epithelial cells (IECs) held together by tight junctions, this delicate structure prevents the transfer of harmful microorganisms, antigens, and toxins from the gut lumen into the circulation. The equilibrium between the rate of apoptosis and shedding of senescent epithelial cells at the villus tip, and the generation of new cells in the crypt, is key to maintaining tissue homeostasis. However, in both localized and systemic inflammation, this balance may be disturbed as a result of pathological IEC shedding. Shedding of IECs from the epithelial monolayer may cause transient gaps or microerosions in the epithelial barrier, resulting in increased intestinal permeability. Although pathological IEC shedding has been observed in mouse models of inflammation and human intestinal conditions such as inflammatory bowel disease, understanding of the underlying mechanisms remains limited. This process may also be an important contributor to systemic and intestinal inflammatory diseases and gut barrier dysfunction in domestic animal species. This review aims to summarize current knowledge about intestinal epithelial cell shedding, its significance in gut barrier dysfunction and host-microbial interactions, and where research in this field is directed.

Infant cervical range of motion in the sagittal plane

Background:

Data pertaining to infant sagittal cervical range of motion (CROM) is lacking. Previous studies have either quantified motions other than sagittal or quantified sagittal range of motion in children >3 years old. Data capture in infants is complex and novel methods are required to overcome previous limitations. Such data is invaluable to inform paediatric injury models, such as those for shaken baby syndrome and automotive safety.

Methods:

Nine infants were recruited from a local group of parents (mean age=406 days, SD=19). Sagittal range-of-motion was measured using two miniature accelerometers (THETAmetrix), which provide orientation angle with respect to gravity. One sensor was placed on the forehead and one over the T2–3 spinous process. Sagittal range of motion was determined by subtracting the tilt angle of thorax sensor from that of the forehead and then summing the total sagittal movement cycle to yield resultant cervical range of motion. Infants were placed in their usual highchair and encouraged to move their head into flexion and extension by a parent focussing their attention on a favourite toy. At the point of maximal motion, the lead researcher applied gentle overpressure to ensure full range was achieved with parental consent. Once one full cycle of sagittal motion was achieved, data collection was terminated.

Results:

Overpressure was not possible in two infants, therefore, their data was omitted. The mean peak sagittal range of motion was 115° (SD=12) with a 95% CI=106–124°.

Conclusions:

The described methods were successful in measuring sagittal CROM in infants and could be used to determine range of motion in even younger infants. The data produced is in agreement with previous reports on older children; however, this method overcomes limitations of other data capture methods.

Implications:

The results provide the first estimate of infant CROM. These data can serve as reference for models of musculoskeletal and neurological injury, including those for shaken baby syndrome and automotive safety.

The reliability of novel multiregional spinal motion measurement device

Background:

Current spinal range of motion (ROM) measurement methods have limitations ranging from the amount of detail obtained to environmental costs and complexity. In particular, limited regional spinal motion is obtained using the current methods. However, a new portable ‘string’ of accelerometers is proposed to overcome these limitations.

Objectives:

This study seeks to determine the reliability of this sensor string in measuring three-dimensional spinal ROM and to investigate the relative motions across six different regions.

Methods:

Two procedures were undertaken on 18 healthy participants. Protocol one: two sensors were placed on the forehead and T1 to measure cervical ROM; and protocol two: six sensors were placed on the spinous processes of T1, T4, T8, T12, L3 and S1 to measure thoraco-lumbar regional ROM.

Results:

The ICC values for all regions were found to be high, ranging from ICC=0.88–0.99 for all movements and regions of the spine, demonstrating that the proposed methods were highly reliable for repeated measures. The standard error of the means (SEMs) were small, ranging from 0.7–5.2°. The flexion/extension motion demonstrated a mean SEM of 1.9° and 1.1° for lateral bending motions. Slightly larger SEMs were observed for rotation, especially for the upper thoracic (UT) and mid thoracic (MT) region with an overall mean SEM of 3.1°. Minimum detectable change (MDC) values ranged from 1.9–14.4°. The flexion/extension motion demonstrated a mean MDC of 5.2° with 3.1° for lateral bending motions. Slightly larger MDCs were observed for rotation (mean MDC=8.4°), especially for the UT and MT region.

Implications:

This method was able to quantify the relative contribution of differing regions to the overall motion. The method described represents a reliable method of assessing spinal ROM across multiple spinal regions.

Signaling mediated by the NF-κB sub-units NF-κB1, NF-κB2 and c-Rel differentially regulate Helicobacter felis-induced gastric carcinogenesis in C57BL/6 mice

The classical nuclear factor-kappaB (NF-κB) signaling pathway has been shown to be important in a number of models of inflammation-associated cancer. In a mouse model of Helicobacter-induced gastric cancer, impairment of classical NF-κB signaling in the gastric epithelium led to the development of increased preneoplastic pathology, however the role of specific NF-κB proteins in Helicobacter-associated gastric cancer development remains poorly understood. To investigate this C57BL/6, Nfkb1^−/−, Nfkb2^−/− and c-Rel^−/− mice were infected with Helicobacter felis for 6 weeks or 12 months. Bacterial colonization, gastric atrophy and preneoplastic changes were assessed histologically and cytokine expression was assessed by qPCR. Nfkb1^−/− mice developed spontaneous gastric atrophy when maintained for 12 months in conventional animal house conditions. They also developed more pronounced gastric atrophy after short-term H. felis colonization with a similar extent of preneoplasia to wild-type (WT) mice after 12 months. c-Rel^−/− mice developed a similar degree of gastric atrophy to WT mice; 3 of 6 of these animals also developed lymphoproliferative lesions after 12 months of infection. Nfkb2^−/− mice developed minimal gastric epithelial pathology even 12 months after H. felis infection. These findings demonstrate that NF-κB1- and NF-κB2-mediated signaling pathways differentially regulate the epithelial consequences of H. felis infection in the stomach, while c-Rel-mediated signaling also appears to modulate the risk of lymphomagenesis in gastric mucosa-associated lymphoid tissue.

Rapid visual stimulation increases extrasynaptic glutamate receptor expression but not visual-evoked potentials in the adult rat primary visual cortex

The model most used to study synaptic plasticity, long-term potentiation (LTP), typically employs electrical stimulation of afferent fibers to induce changes in synaptic strength. It would be beneficial for understanding the behavioral relevance of LTP if a model could be developed that used more naturalistic stimuli. Recent evidence suggests that the adult visual cortex, previously thought to have lost most of its plasticity once past the critical period, is in fact capable of LTP-like changes in synaptic strength in response to sensory manipulations alone. In a preliminary study, we used a photic tetanus (PT; flashing checkerboard stimulus) to induce an enhancement of the visual-evoked potential (VEP) in the primary visual cortex of anesthetised adult rats. In the present study, we sought to compare the mechanisms of this novel sensory LTP with those of traditional electrical LTP. Unexpectedly, we found that sensory LTP was not induced as reliably as we had observed previously, as manipulations of several parameters failed to lead to significant potentiation of the VEP. However, we did observe a significant increase in visual cortex glutamate receptor expression on the surface of isolated synapses following the PT. Both AMPA receptor expression and N-methyl-d-aspartate (NMDA) receptor subunit expression were increased, specifically in extrasynaptic regions of the membrane, in PT animals. These results provide biochemical confirmation of the lack of change in the VEP in response to PT, but suggest that PT may prime synapses for strengthening upon appropriate subsequent activation, through the trafficking of glutamate receptors to the cell surface.

Ultrasonographic findings of the pancreas in cats with elevated serum pancreatic lipase immunoreactivity

BACKGROUND

Pancreatitis is a common disease in cats that is difficult to diagnose.

HYPOTHESIS/OBJECTIVES

To determine the sensitivity and specificity of ultrasonographic changes of the pancreas with serum feline pancreatic lipase immunoreactivity (fPLI) as the standard for diagnosis of pancreatitis.

ANIMALS

35 cats with clinical signs consistent with pancreatitis with an abdominal ultrasound examination and serum fPLI concentration measured within 3 days of the ultrasound.

METHODS

Retrospective study: Pancreatic thickness, pancreatic margination, pancreatic echogenicity, and peripancreatic fat echogenicity were evaluated. Sensitivity and specificity were calculated with an elevated serum fPLI concentration indicative of pancreatitis as the standard for diagnosis.

RESULTS

Serum fPLI was elevated and diagnostic for pancreatitis in 19 of 35 cats. The single ultrasound characteristic with the highest sensitivity was hyperechoic peripancreatic fat at 68% (95% confidence interval = 44-87%), indicating a moderate probability that cats with pancreatitis will have this abnormality on ultrasonographic examination. Specificity was >90% for each of increased pancreatic thickness, abnormal pancreatic margin, and hyperechoic peripancreatic fat. The sensitivity and specificity of ultrasound were 84% (95% confidence interval = 60-97%) and 75% (95% confidence interval = 48-93%), respectively, in cats with elevated serum fPLI indicative of pancreatitis.

CONCLUSIONS AND CLINICAL IMPORTANCE

The presence of a thick left limb of the pancreas, severely irregular pancreatic margins, and hyperechoic peripancreatic fat in cats with appropriate clinical signs and elevated serum fPLI are highly supportive of pancreatitis.

A low noise preamplifier with optoelectronic overload protection for radioactivity measurement

Pulses from detectors used for radioactivity measurement can vary in size by several orders of magnitude. Large pulses will lead to saturation at the preamplifier output and extension of the pulse length. As a consequence, the dead time of the system increases and pulses may be lost. Electronic design techniques employed to protect against overloading tend to increase the amplifier noise level. However, an optoelectronic method of overload protection has been devised which has only a negligible effect on noise. An infrared light emitting diode interfaced to the output of the preamplifier is linked by fibre optic cable to an ultra-low leakage photodiode at the input. The conduction of the photodiode increases with the amplitude of the preamplifier output signal. Excess current is thereby prevented from entering the preamplifier and causing saturation. The preamplifier has been tested on 4π beta-gamma and gas counting systems and found to give good protection against overloading.

Life-extending dietary restriction and ovariectomy result in similar feeding rates but different physiologic responses in grasshoppers

Dietary restriction (DR) and reduced reproduction each extend life span in many species. Females undergoing DR typically experience a reduction in their fecundity, which raises the question of whether the two treatments are actually extending life span in overlapping ways. Life span in lubber grasshoppers has been shown to be increased by DR, and separately by ovariectomy (OVX). Here, we test the combination of these on life span. If life extension by the two treatments are additive, it would suggest that they likely act through separate pathways. The experimental groups were: fully reproductive and fully fed (ShamFD); ovariectomized and fully fed (OVXFD); fully reproductive and restricted diet (ShamDR); and ovariectomized and restricted diet (OVXDR). The median life spans of these groups were: ShamFD=245 d, OVXFD=285 d, ShamDR=286 d, and OVXDR=322 d. Feeding rate for the OVXFD group was 64% of ad libitum, similar to the 70% of ad libitum that was used for ShamDR. We also measured hemolymph parameters of physiology in these same individuals. Hemolymph levels of vitellogenin (the egg yolk-precursor protein) were increased 5-fold by OVX, but were not affected by DR. In addition, hemolymph total anti-oxidant activity (per μg protein) was significantly reduced by OVX, but was not affected by DR. We show that OVX and DR produce different physiological responses in grasshoppers, despite life extensions and feeding levels that were not significantly different. These data suggest that OVX and DR might extend life span via distinct pathways.

The OARSI histopathology initiative - recommendations for histological assessments of osteoarthritis in the rabbit

AIM

The primary goal of this body of work is to suggest a standardized system for histopathological assessment of experimental surgical instability models of osteoarthritis (OA) in rabbits, building on past experience, to achieve comparability of studies from different centres. An additional objective is to review methodologies that have been employed in the past for assessing OA in rabbits with particular reference to the surgical anterior cruciate ligament transection (ACLT) model.

METHODS

A panel of scientists and clinician-scientists with recognized expertise in assessing rabbit models of OA reviewed the literature to provide a critical appraisal of the methods that have been employed to assess both macroscopic and microscopic changes occurring in rabbit joint tissues in experimental OA. In addition, a validation of the proposed histologic histochemical grading system was performed.

RESULTS

The ACLT variant of the surgical instability model in skeletally mature rabbits is the variation most capable of reproducing the entire range of cartilage, synovial and bone lesions recognized to be associated with OA. These lesions can be semiquantitatively graded using macroscopic and microscopic techniques. Further, as well as cartilage lesions, this ACLT model can produce synovial and bone lesions similar to that of human OA.

CONCLUSIONS

The ACLT variant of the surgical instability model in rabbits is a reproducible and effective model of OA. The cartilage lesions in this model and their response to therapy can be graded according to an adapted histological and histochemical grading system, though also this system is to some extent subjective and, thus, neither objective nor entirely reproducible.

Metal cluster chemistry: Structure and stereochemistry in the polynuclear rhodium hydrides H(n)Rh(n)[P(OR)(3)](2n)

Crystallographic analyses of x-ray and neutron diffraction data have provided a definitive structural representation of {HRh[P(O-i-C(3)H(7))(3)](2)}(2) and {HRh[P(OCH(3))(3)](2)}(3). These polynuclear hydrides are generated from square planar H(2)Rh[P(OR)(3)](2) units by edge (hydrogen atom) sharing and by vertex (hydrogen atom) sharing to form the dimeric and trimeric structures, respectively. The square-planar units are held together through four-center and three-center two-electron Rh-H-Rh bonds in the dimer and trimer, respectively. The dimer and trimer molecules each add one molecule of hydrogen to form H[(i-C(3)H(7)O)(3)P](2)RhH(3)Rh [P(O-i-C(3)H(7))(3)](2) and H(5)Rh(3)[P(OCH(3))(3)](6), respectively. NMR spectral information has served to define the stereochemical features of these polyhydrides. The significance of this chemistry in the metal cluster-metal surface analogy is described.

Selective potentiation of the metabotropic glutamate receptor subtype 2 blocks phencyclidine-induced hyperlocomotion and brain activation

Previous preclinical and clinical studies have demonstrated the efficacy of group II metabotropic glutamate receptor (mGluR) agonists as potential antipsychotics. Recent studies utilizing mGluR2-, mGluR3-, and double knockout mice support that the antipsychotic effects of those compounds are mediated by mGluR2. Indeed, biphenyl indanone-A (BINA), an allosteric potentiator of mGluR2, is effective in experimental models of psychosis, blocking phencyclidine (PCP)-induced hyperlocomotion and prepulse inhibition deficits in mice. In this study, we administered the NMDA receptor antagonist PCP (5.6 mg/kg i.p.) to rats, an established animal model predictive of schizophrenia. Here, we show that BINA (32 mg/kg i.p.) attenuated PCP-induced locomotor activity in rats. Using behaviorally relevant doses of BINA and PCP, we performed pharmacological magnetic resonance imaging (phMRI) to assess the specific brain regions that underlie the psychotomimetic effects of PCP, and examined how BINA modulated the PCP-induced functional changes in vivo. In anesthetized rats, acute administration of PCP produced robust, sustained blood oxygenation level-dependent (BOLD) activation in specific cortical, limbic, thalamic, and striatal regions. Pretreatment with BINA suppressed the amplitude of the BOLD response to PCP in the prefrontal cortex, caudaute-putamen, nucleus accumbens, and mediodorsal thalamus. Our results show key brain structures underlying PCP-induced behaviors in a preclinical model of schizophrenia, and, importantly, its reversal by potentiation of mGluR2 by BINA, revealing specific brain regions functionally involved in its pharmacological action. Finally, our findings bolster the growing body of evidence that mGluR2 is a viable target for the treatment of schizophrenia.

Lower quit rates among African American and Latino menthol cigarette smokers at a tobacco treatment clinic

BACKGROUND

Lower rates of smoking cessation and higher rates of lung cancer in African American (AA) smokers may be linked to their preference for mentholated cigarettes.

AIM

This study assessed the relationship between menthol smoking, race/ethnicity and smoking cessation among a diverse cohort of 1688 patients attending a specialist smoking cessation service.

RESULTS

46% of the patients smoked mentholated cigarettes, but significantly more AA (81%) and Latino (66%) patients than Whites (32%) smoked menthols. AA and Latino menthol smokers smoked significantly fewer cigarettes per day (CPD) than non-menthol smokers (15.7 vs. 20.3, for AA, and 17.0 vs. 22.1, for Latinos), with no differences among White menthol and non-menthol smokers. At 4-week follow up, AA, Latino and White non-menthol smokers had similar quit rates (54%, 50% and 50% respectively). In contrast, among menthol smokers, AAs and Latinos had lower quit rates (30% and 23% respectively) compared with Whites (43%, p < 0.001). AA and Latino menthol smokers had significantly lower odds of quitting [odds ratio (OR) = 0.34; 95% CI = 0.17, 0.69 for AA, and OR = 0.32; 95% CI = 0.16, 0.62 for Latinos] than their non-menthol counterparts. At 6-month follow up, a similar trend was observed for the race/ethnicity subgroups, with AA menthol smokers having half the odds of being abstinent compared with AA non-menthol smokers (OR = 0.48; 95% CI = 0.25, 0.9).

CONCLUSIONS

Despite smoking fewer CPD, AA and Latino menthol smokers experience reduced success in quitting as compared with non-menthol smokers within the same ethnic/racial groups.

Causes of death in the Kasekela chimpanzees of Gombe National Park, Tanzania

Understanding the rates and causes of mortality in wild chimpanzee populations has important implications for a variety of fields, including wildlife conservation and human evolution. Because chimpanzees are long-lived, accurate mortality data requires very long-term studies. Here, we analyze 47 years of data on the Kasekela community in Gombe National Park. Community size fluctuated between 38 and 60, containing 60 individuals in 2006. From records on 220 chimpanzees and 130 deaths, we found that the most important cause of mortality in the Kasekela community was illness (58% of deaths with known cause), followed by intraspecific aggression (20% of deaths with known cause). Previous studies at other sites also found that illness was the primary cause of mortality and that some epidemic disease could be traced to humans. As at other study sites, most deaths due to illness occurred during epidemics, and the most common category of disease was respiratory. Intraspecific lethal aggression occurred within the community, including the killing of infants by both males and females, and among adult males during the course of dominance-related aggression. Aggression between communities resulted in the deaths of at least five adult males and two adult females in the Kasekela and Kahama communities. The frequency of intercommunity violence appears to vary considerably among sites and over time. Intercommunity lethal aggression involving the Kasekela community was observed most frequently during two periods. Other less common causes of death included injury, loss of mother, maternal disability, and poaching.

The acute management of head injury

The management of traumatic brain injury has undergone extensive revision as the results of large collaborative outcome studies have cast doubt on many traditional 'common sense' practices. The primary goal of identifying and treating intracranial hypertension has given way to a focus on secondary brain ischemia, in which cerebral perfusion pressure and oxygen delivery have gained new importance. With the exception of impending herniation, the routine use of hyperventilation and high-dose barbiturates is no longer recommended. Hypertonic saline, given as intermittent boluses, has joined mannitol as an effective means of reducing cerebral edema. Preliminary results from a large multi-center study have cast doubt on the benefit of the broad application of hypothermia in improving outcome in traumatic brain injury.

Mannose-binding lectin gene polymorphisms in a cohort study of ANCA-associated small vessel vasculitis

OBJECTIVE

To investigate whether single nucleotide polymorphisms (SNPs) within the mannose-binding lectin (MBL) gene are associated with small vessel vasculitis (SVV) and are a risk factor for intercurrent infection, as described previously in other autoimmune diseases.

METHODS

Six SNPs in the MBL promoter and coding region were genotyped by sequence-specific polymerase chain reaction or restriction fragment length polymorphism assay in 170 white Caucasians with SVV and 372 ethnically matched controls in a case-control association study. Serum MBL levels were measured by ELISA. The genotype and protein concentrations were correlated to clinical details retrieved from hospital records.

RESULTS

No differences in allelic and genotypic frequencies were detected between patients with SVV and control subjects. MBL deficiency did not increase the susceptibility to infection (P = 0.6, Fisher's exact test) or the duration of hospital stay.

CONCLUSION

Our data suggest that MBL polymorphisms are not associated with SVV and do not influence the incidence of concomitant infections. These results raise doubts about the usefulness of MBL polymorphisms as a predictive marker for infection in SVV.

Dopamine transporter activity mediates amphetamine-induced inhibition of Akt through a Ca2+/calmodulin-dependent kinase II-dependent mechanism

The primary mechanism for clearance of extracellular dopamine (DA) is uptake mediated by the dopamine transporter (DAT), which is governed, in part, by the number of functional DATs on the cell surface. Previous studies have shown that amphetamine (AMPH) decreases DAT cell surface expression, whereas insulin reverses this effect through the action of phosphatidylinositol 3-kinase (PI3K). Therefore, it is possible that AMPH causes DAT cell surface redistribution by inhibiting basal insulin signaling. Here, we show in a heterologous expression system and in murine striatal synaptosomes that AMPH causes a time-dependent decrease in the activity of Akt, a protein kinase immediately downstream of PI3K. This effect was blocked by the DAT inhibitor cocaine, suggesting that AMPH must interact with DAT to inhibit Akt. We also showed that AMPH is able to stimulate Ca2+/calmodulin-dependent kinase II (CaMKII) activity, both in the heterologous expression system as well as in murine striatal synaptosomes. The ability of AMPH to decrease Akt activity was blocked by the CaMKII inhibitor 2-[N-(2-hydroxyethyl)]-N-(4-methoxybenzenesulfonyl)]amino-N-(4-chlorocinnamyl)-N-methylbenzylamine (KN93), but not by its inactive analog 2-[N-(4-methoxybenzenesulfonyl)]amino-N-(4-chlorocinnamyl)-N-methylbenzylamine (KN92). Furthermore, preincubation with KN93 prevented the AMPH-induced decrease in DAT cell surface expression. Thus, AMPH, but not cocaine, decreases Akt activity through a CaMKII-dependent pathway, thereby providing a novel mechanism by which AMPH regulates insulin signaling and DAT trafficking.

IL-18 is upregulated in the kidney and primes neutrophil responsiveness in ANCA-associated vasculitis

In antineutrophil cytoplasm autoantibody (ANCA)-associated systemic vasculitis (ASV), autoantibody-induced neutrophil activation is believed to cause organ damage. In vitro, tumor necrosis factor alpha (TNFalpha) primes neutrophils for ANCA stimulation and TNFalpha blockade has been successfully used to treat ASV. Nonetheless, irreversible organ damage can still occur, suggesting that other cytokines may circumvent TNFalpha blockade. We report that interleukin (IL)-18 deposition, as assessed by immunoperoxidase staining, is increased in renal biopsies from ASV patients. Immunofluorescence microscopy demonstrated that podocytes are the predominant glomerular IL-18-positive cell type, whereas in the interstitium, myofibroblasts, distal tubular epithelium, and infiltrating macrophages stained for IL-18. In vitro, IL-18 primed superoxide production by ANCA-activated neutrophils comparably to TNFalpha. IL-18-primed, ANCA-induced superoxide production was unaffected by anti-TNFalpha antibody, which abrogated TNFalpha priming. Furthermore, TNFalpha and IL-18 phosphorylated neutrophil p38 mitogen-activated protein kinase (MAPK), but IL-18-mediated p38 MAPK phosphorylation was unaffected by anti-TNFalpha antibody. The p38 MAPK inhibitor, SB20358, reduced IL-18-primed, ANCA-induced superoxide production in a concentration-dependent manner. ANCA-induced superoxide release was also sensitive to the Leukotriene B4 (LTB4) inhibitor MK-886. IL-18 priming was not associated with increased ANCA antigen expression on isolated neutrophils. We conclude that IL-18 is likely to be important for neutrophil recruitment and priming in ASV. Therapies targeting single priming agents may have limited efficacy in controlling disease.

The dopamine transporter: a vigilant border control for psychostimulant action

Neurotransmission within the mesocorticolimbic dopamine system has remained the central focus of investigation into the molecular, cellular and behavioral properties of psychostimulants for nearly three decades. The primary means by which dopamine transmission in the synapse is terminated is via the dopamine transporter (DAT), the presynaptic plasmalemmal protein that is responsible for the reuptake of released dopamine. Numerous abused as well as clinically important drugs have important pharmacological interactions with DAT. In general, these compounds fall into two categories: those that block dopamine transport (e.g., cocaine, methylphenidate) and those that serve as substrates for transport [e.g., dopamine, amphetamine and 3,4-methylenedioxymethamphetamine (MDMA or "ecstasy")]. Recent data from in vitro and in vivo studies have suggested that DAT, like other biogenic amine transporters, share several characteristics with classical ligand-gated ion channels. In addition, substrates for transport promote redistribution of DAT away from the plasma membrane, while transport inhibitors such as cocaine disrupt this process. In addition, presynaptic autoreceptors for dopamine have been implicated in the modulation of DAT surface expression and function. The present chapter summarizes some of the recent discoveries pertaining to the electrogenic properties of DAT and their potential relevance to the effects of amphetamine-like stimulants on DAT function. Although there are a number of intracellular and extracellular modulatory influences on dopamine clearance that may play particular roles in psychostimulant action, we specifically focus on the differential direct modulation of DAT function by transport substrates and inhibitors, and we also discusses the role of presynaptic D2 receptors in transport regulation.

Engineering craniofacial scaffolds

OBJECTIVE

To develop an integrated approach for engineering craniofacial scaffolds and to demonstrate that these engineered scaffolds would have mechanical properties in the range of craniofacial tissue and support bone regeneration for craniofacial reconstruction.

EXPERIMENTAL VARIABLE

Scaffold architecture designed to achieve desired elasticity and permeability. Scaffold external shape designed to match craniofacial anatomy.

OUTCOME MEASURE

Final fabricated biomaterial scaffolds. Compressive mechanical modulus and strength. Bone regeneration as measured by micro-CT scanning, mechanical testing and histology.

SETTING

Departments of Biomedical Engineering, Oral/Maxillofacial Surgery, and Oral Medicine, Pathology and Oncology at the University of Michigan.

RESULTS

Results showed that the design/fabrication approach could create scaffolds with designed porous architecture to match craniofacial anatomy. These scaffolds could be fabricated from a wide range of biomaterials, including titanium, degradable polymers, and degradable calcium phosphate ceramics. Mechanical tests showed that fabricated scaffolds had compressive modulus ranging 50 to 2900 MPa and compressive strength ranging from 2 to over 56 MPa, within the range of human craniofacial trabecular bone. In vivo testing of designed scaffolds showed that they could support bone regeneration via delivery of BMP-7 transduced human gingival fibroblasts in a mouse model. Designed hydroxyapatite scaffolds with pore diameters ranging from 400 to 1200 microns were implanted in minipig mandibular defects for 6 and 18 weeks. Results showed substantial bone ingrowth (between 40 and 50% at 6 weeks, between 70 and 80% at 18 weeks) for all scaffolds, with no significant difference based on pore diameter.

CONCLUSION

Integrated image-based design and solid free-form fabrication can create scaffolds that attain desired elasticity and permeability while fitting any 3D craniofacial defect. The scaffolds could be manufactured from degradable polymers, calcium phosphate ceramics and titanium. The designed scaffolds supported significant bone regeneration for all pore sizes ranging from 300 to 1200 microns. These results suggest that designed scaffolds are clinically applicable for complex craniofacial reconstruction.

Developmental differences in understanding the causes, controllability and chronicity of disabilities

OBJECTIVE

The present study explored typically developing children's (n = 77) understanding of the causes, controllability and chronicity of disabilities.

DESIGN

Children in each of four age groups (4-5 years, 6-7 years, 9-10 years and 11-12 years) were interviewed to explore their ideas about children with physical disabilities (minor: missing thumb; major: wheel-chair bound), sensory disabilities (blindness and hearing loss), learning disabilities (non-specific and Down syndrome) and emotional/behavioural difficulties (attention deficit hyperactivity disorder and lack of social skills).

RESULTS

Significant age differences were found in children's understandings of the causes, controllability and chronicity of disabilities. Furthermore, children showed a greater understanding of salient disabilities.

CONCLUSIONS

Findings are discussed in terms of developmental changes and the role of experience in shaping children's understanding of disabilities.

Anti-endothelial cell antibodies from lupus patients bind to apoptotic endothelial cells promoting macrophage phagocytosis but do not induce apoptosis

OBJECTIVE

Anti-endothelial cell antibodies (AECA) have been reported to induce apoptosis. We investigated the induction of apoptosis by these autoantibodies and their involvement in the removal of apoptotic cells.

METHODS

AECA isolated from patients with active systemic lupus erythematosus (SLE) were incubated with human umbilical vein endothelial cells (HUVECs). AECA-positive sera were identified using a cell-based ELISA. Apoptosis was measured by morphology and phosphatidylserine externalization using flow cytometry with fluorescein isothiocyanate (FITC)-conjugated annexin V. Flow cytometry was used to investigate AECA binding to apoptotic cells using FITC-conjugated anti-human immunoglobulin G (IgG). Apoptotic endothelial cells were stained with a red dye (PKH26) and co-cultured with macrophages, and phagocytosis was visualized under phase contrast microscopy.

RESULTS

AECA from patients with SLE did not induce apoptosis compared with normal IgG (nIgG) at any time point, as assessed by morphology (at 24 h, P = 0.167) or phosphatidylserine externalization (at 24 h, P = 0.098). However, there was increased binding of AECA to apoptotic endothelial cells (48.8 +/- 11.9 compared with 25.8 +/- 6.7% AECA binding to freshly isolated cells, P< 0.001). These opsonized endothelial cells showed greater phagocytosis by macrophages (mean phagocytic index 24.9 +/- 4.5%) when cells opsonized with nIgG were compared with AECA (34.8 +/- 3.4% n = 5, P = 0.01).

CONCLUSION

In conclusion, AECA bind to apoptotic endothelial cells but do not induce endothelial cell apoptosis. Macrophage phagocytosis is increased by opsonization of apoptotic endothelial cells by AECA, a proinflammatory mechanism of cell removal.

The importance of resolution of inflammation in the pathogenesis of ANCA-associated vasculitis

The primary small-vessel systemic vasculitides are disorders that target small blood vessels, inducing vessel wall inflammation, and are associated with the development of anti-neutrophil cytoplasmic antibodies. Multiple organs are attacked, including the lungs and kidneys. Increasing knowledge of pathogenesis suggests that the antibodies activate neutrophils inappropriately, leading to endothelial and vascular damage. Cytokines, such as tumour necrosis factor, can facilitate damage by priming the neutrophils and activating endothelial cells. Apoptosis of infiltrating neutrophils is also disrupted by anti-neutrophil cytoplasmic antibody activation, and removal of these effete cells occurs in a pro-inflammatory manner, promoting persistent inflammation. The autoimmune response may be promoted by aberrant phagocytosis of apoptotic neutrophils by dendritic cells. Understanding the pathogenesis can help to rationalize existing therapies and indicate new approaches to therapy.

Prevention of heterotopic ossification after spinal cord injury with COX-2 selective inhibitor (rofecoxib)

STUDY DESIGN

A randomized, prospective, double-blind, placebo-controlled clinical trial.

OBJECTIVES

To determine the effect of COX-2-selective inhibitor on the prevention of heterotopic ossification (HO) after spinal cord injury (SCI).

SETTING

County and University Teaching Hospital, Miami, FL, USA.

METHODS

A total of 76 patients were enrolled in the study. Among them, 39 patients received placebo, and 37 received COX-2-selective inhibitor rofecoxib 25 mg daily for a period of 4 weeks. Prevention was started 3 weeks after spinal cord injury (SCI). In both groups of patients there was similar age as well as the level of SCI and ASIA impairment scale. Two methods were used to diagnose early HO, clinical symptoms and bone scintigraphy. Radiography was used for diagnosis of late stages of HO development.

RESULTS

A significantly lower incidence of HO was found in the rofecoxib group (13.4%) than in the placebo group (33.3%: P<0.05). In patients receiving rofecoxib, there was a 2.5 times lower relative risk of developing HO than in the placebo group (95% CI, 2.3-6). There were no patients who discontinued the study due to adverse effects of medication.

CONCLUSION

Our data suggest that COX-2-selective inhibitor rofecoxib is an effective medication in prevention of HO after SCI.