Memory deficits and hippocampal cytokine expression in a rat model of ADHD

Attention-deficit/hyperactivity disorder (ADHD) is a complex behavioral disorder characterized by hyperactivity, impulsivity, inattention, and deficits in working memory and time perception. While animal models have advanced our neurobiological understanding of this condition, there are limited and inconsistent data on working and elapsed time memory function. Inflammatory signaling has been identified as a key factor in memory and cognitive impairments, but its role in ADHD remains unclear. Additionally, the disproportionate investigation of male subjects in ADHD research has contributed to a poor understanding of the disorder in females. This study sought to investigate the potential connections between memory, neuroimmunology, and ADHD in both male and female animals. Specifically, we utilized the spontaneously hypertensive rat (SHR), one of the most extensively studied animal models of ADHD. Compared to their control, the Wistar-Kyoto (WKY) rat, male SHR are reported to exhibit several behavioral phenotypes associated with ADHD, including hyperactivity, impulsivity, and poor sustained attention, along with impairments in learning and memory. As the hippocampus is a key brain region for learning and memory, we examined the behavior of male and female SHR and WKY rats in two hippocampal-dependent memory tasks. Our findings revealed that SHR have delay-dependent working memory deficits that were similar to, albeit less severe than, those seen in hippocampal-lesioned rats. We also observed impairments in elapsed time processing in female SHR, particularly in the discrimination of longer time durations. To investigate the impact of inflammatory signaling on memory in these rats, we analyzed the levels of several cytokines in the dorsal and ventral hippocampus of SHR and WKY. Although we found some sex and genotype differences, concentrations were generally similar between groups. Taken together, our results indicate that SHR exhibit deficits in spatial working memory and memory for elapsed time, as well as some differences in hippocampal cytokine concentrations. These findings contribute to a better understanding of the neurobiological basis of ADHD in both sexes and may inform future research aimed at developing effective treatments for the disorder. Nonetheless, the potential mediating role of neuroinflammation in the memory symptomatology of SHR requires further investigation.

Medial entorhinal cortex lesions produce delay-dependent disruptions in memory for elapsed time

Our memory for time is a fundamental ability that we use to judge the duration of events, put our experiences into a temporal context, and decide when to initiate actions. The medial entorhinal cortex (MEC), with its direct projections to the hippocampus, has been proposed to be the key source of temporal information for hippocampal time cells. However, the behavioral relevance of such temporal firing patterns remains unclear, as most of the paradigms used for the study of temporal processing and time cells are either spatial tasks or tasks for which MEC function is not required. In this study, we asked whether the MEC is necessary for rats to perform a time duration discrimination task (TDD), in which rats were trained to discriminate between 10-s and 20-s delay intervals. After reaching a 90% performance criterion, the rats were assigned to receive an excitotoxic MEC-lesion or sham-lesion surgery. We found that after recovering from surgery, rats with MEC lesions were impaired on the TDD task in comparison to rats with sham lesions, failing to return to criterion performance. Their impairment, however, was specific to the longer, 20-s delay trials. These results indicate that time processing is dependent on MEC neural computations only for delays that exceed 10 s, perhaps because long-term memory resources are needed to keep track of longer time intervals.

Macroplastic pollution in freshwater environments: Focusing public and policy action

Understanding and managing plastic pollution is an increasingly important environmental priority for policy makers, businesses and scientists. Awareness of the potential damage to the world's oceans has grown but there is less attention given to freshwater ecosystems. Yet, rivers are the dominant source of plastic pollution to the marine environment, as well as a potential sink, accumulating plastic from multiple sources. Actions to reduce the presence of macroplastics in rivers is fundamental to conserving both freshwater and marine environments, but there is limited understanding of potential pollution sources, vectors and storage. Importantly, there are only a handful of studies examining the typologies of freshwater macroplastic pollution, often using different categories and collection methods. This impedes setting priorities for scientific investigation and mitigation measures. The present study identifies the most prevalent macroplastic items in freshwater environments in Europe, with a focus on consumer plastic items, i.e. those that could potentially be reduced by targeted actions by the public, as well as industrial and government intervention. Our analysis addresses the differences between reported macroplastics in freshwater and marine environments as well as those estimated from litter rates. Our results identify a macroplastic "top ten", i.e. those dominant plastic typologies that require a more focused effort to reformulate their use and management, as well as setting a common baseline for a more consistent data gathering and reporting approach.

The Role of Tourism and Recreation in the Spread of Non-Native Species: A Systematic Review and Meta-Analysis

Managing the pathways by which non-native species are introduced and spread is considered the most effective way of preventing species invasions. Tourism and outdoor recreation involve the frequent congregation of people, vehicles and vessels from geographically diverse areas. They are therefore perceived to be major pathways for the movement of non-native species, and ones that will become increasingly important with the continued growth of these sectors. However, a global assessment of the relationship between tourism activities and the introduction of non-native species–particularly in freshwater and marine environments–is lacking. We conducted a systematic review and meta-analysis to determine the impact of tourism and outdoor recreation on non-native species in terrestrial, marine and freshwater environments. Our results provide quantitative evidence that the abundance and richness of non-native species are significantly higher in sites where tourist activities take place than in control sites. The pattern was consistent across terrestrial, freshwater and marine environments; across a variety of vectors (e.g. horses, hikers, yachts); and across a range of taxonomic groups. These results highlight the need for widespread biosecurity interventions to prevent the inadvertent introduction of invasive non-native species (INNS) as the tourism and outdoor recreation sectors grow.

Invaders in hot water: a simple decontamination method to prevent the accidental spread of aquatic invasive non-native species

Watersports equipment can act as a vector for the introduction and spread of invasive non native species (INNS) in freshwater environments. To support advice given to recreational water users under the UK Government’s Check Clean Dry biosecurity campaign and ensure its effectiveness at killing a range of aquatic INNS, we conducted a survival experiment on seven INNS which pose a high risk to UK freshwaters. The efficacy of exposure to hot water (45 °C, 15 min) was tested as a method by which waters users could ‘clean’ their equipment and was compared to drying and a control group (no treatment). Hot water had caused 99 % mortality across all species 1 h after treatment and was more effective than drying at all time points (1 h: χ² = 117.24, p < 0.001; 1 day χ² = 95.68, p < 0.001; 8 days χ² = 12.16, p < 0.001 and 16 days χ² = 7.58, p < 0.001). Drying caused significantly higher mortality than the control (no action) from day 4 (χ² = 8.49, p < 0.01) onwards. In the absence of hot water or drying, 6/7 of these species survived for 16 days, highlighting the importance of good biosecurity practice to reduce the risk of accidental spread. In an additional experiment the minimum lethal temperature and exposure time in hot water to cause 100 % mortality in American signal crayfish (Pacifastacus leniusculus), was determined to be 5 min at 40 °C. Hot water provides a simple, rapid and effective method to clean equipment. We recommend that it is advocated in future biosecurity awareness campaigns.

Biosecurity and vector behaviour: evaluating the potential threat posed by anglers and canoeists as pathways for the spread of invasive non-native species and pathogens

Invasive non-native species (INNS) endanger native biodiversity and are a major economic problem. The management of pathways to prevent their introduction and establishment is a key target in the Convention on Biological Diversity's Aichi biodiversity targets for 2020. Freshwater environments are particularly susceptible to invasions as they are exposed to multiple introduction pathways, including non-native fish stocking and the release of boat ballast water. Since many freshwater INNS and aquatic pathogens can survive for several days in damp environments, there is potential for transport between water catchments on the equipment used by recreational anglers and canoeists. To quantify this biosecurity risk, we conducted an online questionnaire with 960 anglers and 599 canoeists to investigate their locations of activity, equipment used, and how frequently equipment was cleaned and/or dried after use. Anglers were also asked about their use and disposal of live bait. Our results indicate that 64% of anglers and 78.5% of canoeists use their equipment/boat in more than one catchment within a fortnight, the survival time of many of the INNS and pathogens considered in this study and that 12% of anglers and 50% of canoeists do so without either cleaning or drying their kit between uses. Furthermore, 8% of anglers and 28% of canoeists had used their equipment overseas without cleaning or drying it after each use which could facilitate both the introduction and secondary spread of INNS in the UK. Our results provide a baseline against which to evaluate the effectiveness of future biosecurity awareness campaigns, and identify groups to target with biosecurity awareness information. Our results also indicate that the biosecurity practices of these groups must improve to reduce the likelihood of inadvertently spreading INNS and pathogens through these activities.

Modelling the effectiveness of vaccination in controlling bovine tuberculosis in wild boar

Context Bovine tuberculosis is a persistent disease of livestock in many parts of the world, especially where wildlife hosts co-exist with livestock. In south-western Spain, despite the widespread implementation of test-and-cull strategies for cattle, the herd prevalence in areas with high wild boar densities remains stable. The control of M. bovis infection in wild boar is likely to be essential for effective disease control in livestock. Methods We developed an individual-based model to evaluate whether vaccinating wild boar piglets with oral bait would be an effective strategy to reduce the prevalence of M. bovis infection in wild boar populations. Specifically, we quantified the proportion of piglets requiring vaccination and the number of years the vaccination programme would need to continue to eradicate bTB from wild boar within 25 years, comparing ‘managed’ populations on hunting estates where supplementary food is provided, with ‘unmanaged’, free-living populations. Successful vaccination was defined as the proportion of piglets that were delivered the vaccine and were effectively protected from infection. Key results Longer-term (25-year) vaccination strategies were more successful than short-term (5-year) strategies at either eradicating M. bovis or reducing it to below 90% of its original prevalence. M. bovis infection could be eradicated under a 25-year vaccination strategy if 80% of piglets were vaccinated in a managed population or 70% of piglets were vaccinated in an unmanaged population. In contrast, 5-year strategies in which 80% of piglets were vaccinated reduced the prevalence of M. bovis only by 27% or 8% in the managed and unmanaged populations, respectively. Conclusions The results of our simulation model, coupled with the promising results of initial vaccine and oral bait-uptake trials in wild boar indicated that vaccination could be an effective strategy to reduce the prevalence of M. bovis infection in wild boar if used in conjunction with other disease-control measures. Implications The vaccination of piglets over a long-term period has the potential to make an important contribution to the eradication of M. bovis infection from wild boar reservoirs in southern Spain.

Equine laryngeal hemiplegia. Part III. Treatment by laryngoplasty

During the years 1971-1979, 127 horses with left laryngeal hemiplegia were studied. The physical characteristics and clinical signs observed in this study were recorded in Part I and Part II of ths series of papers. Of these 127 horses, 81 were treated by the laryngoplasty procedure. Complications of surgery are described and the effects of the operation on respiratory noise and performance are evaluated. In 54.8% of horses the chronic respiratory noise observed during exercise was apparently diminished or eliminated post-operatively. The performance of 44% of horses was apparently improved after surgery. Post-operative racing success occurred in 38% of horses treated. Satisfactory arytenoid adduction as assessed endoscopically within 9 days of surgery was achieved in 77% of cases. Surgical failure appeared to be related to cutting of the laryngeal cartilages by the prosthesis and techniques to minimise this are discussed.

Health care quality and rheumatology: the role of the American College of Rheumatology (ACR)

In the context of undeniable evidence that health care can and must be improved, the ACR has committed to lead the effort to develop and implement quality measures designed to identify opportunities to improve sub-optimal care. In the process of creating and offering tools to measure and assess adherence to evidence-based care, the ACR seeks to be proactive in preparing its member physicians and their practice teams for the likely upcoming healthcare environment shift to more quality-based reimbursement and public reporting.

The MOA: an integral part of quality assurance activities

Ready or not, the medical office audit (MOA) is an integral part of health maintenance organizations' (HMOs') quality assurance activities. Criteria for the MOA, including external and internal considerations, staffing issues, medical records, and patient safety concerns, are reviewed in this article.

Heparin-releasable lipoprotein lipase activity is increased in cardiomyocytes after culture

The activity of lipoprotein lipase (LPL) in adult rat heart cardiomyocytes after overnight culture on laminin-coated plates for 18-22 h was compared with enzyme activity in freshly isolated cardiomyocytes. LPL activity in cellular homogenates from cultured cardiomyocytes and freshly isolated cells was 240 and 233 nmol oleate released h-1.mg-1 protein, respectively. LPL specific activity (mU/ng LPL protein) was 0.07 in cultured cells compared with 0.42 in freshly isolated cells, indicating an increased content of inactive LPL mass after overnight culture. The heparin-induced release of LPL activity into the medium of cultured cardiomyocytes (198 nmol.h-1.mg-1) was much greater than heparin-releasable LPL (HR-LPL) activity (59 nmol.h-1.mg-1) from freshly isolated cells. HR-LPL activity from cultured cardiomyocytes was dependent on serum (16.3-fold activation) and was inhibited by high ionic strength (1 M NaCl) and by a polyclonal antibody to LPL. Cultured cardiomyocytes also had more immunodetectable LPL on the cell surface compared with freshly isolated cardiomyocytes, consistent with increased HR-LPL activity. Therefore, overnight culture may permit cardiomyocytes time to recover from the stress of isolation by increasing the content of LPL on the cell surface.

Fatty acids reduce heparin-releasable LPL activity in cultured cardiomyocytes from rat heart

Varying glucose and fatty acid (FA) concentrations in the medium of cultured cardiomyocytes from adult rat hearts were tested for effects on lipoprotein lipase (LPL) activity. Glucose (5.5, 11, and 25 mM in the culture medium for 18-22 h) had no effect on either heparin-releasable LPL (HR-LPL) or on cellular LPL (C-LPL) activities. When cardiomyocytes were cultured overnight with 60 microM oleate, HR-LPL activity was reduced to 20% of control, with no change in C-LPL activity or total C-LPL mass. Similar results (HR-LPL and C-LPL activities) were obtained with 60 microM concentrations of palmitate and myristate; linoleate and eicosapentaenoate did reduce C-LPL activity, but the decrease in HR-LPL activity was much greater. Oxfenicine, an FA oxidation inhibitor, did not alter the inhibitory effect of 60 microM oleate on HR-LPL. Short-term incubations (1 and 3 h) of cultured cardiomyocytes with 60 microM oleate did not displace LPL into the medium. Immunodetectable LPL on the cell surface of oleate-treated cultured cardiomyocytes was increased compared with control cells, but heparin treatment released the same amount of LPL mass that had reduced catalytic activity.

A 42-year-old woman with low back pain

The following case is presented to illustrate the roentgenographic and clinical findings of a condition of interest to orthopedic surgeons. The initial history, physical findings, and roentgenographic examinations are noted on this page. The clinical and roentgenographic diagnoses are presented on the following pages.

Hypoglycaemic brain damage: effect of a dihydropyridine calcium channel antagonist in rats

Hypoglycaemic brain damage consists of selective necrosis of cerebral neurons related to the extracellular release of excitatory amino acids. Neuronal excitatory amino acid receptors are activated and calcium channels are opened. The present investigation was designed to test the effectiveness of dihydropyridine blockade of voltage-sensitive calcium channels in hypoglycaemic brain damage. Sixty-four rats were given either high-dose nimodipine, consisting of an initial bolus of 300 micrograms/kg nimodipine administered at the stage of EEG slowing (blood glucose levels of 1.0-1.5 mmol/l), followed by continuous intravenous nimodipine infusion at 1.5 micrograms.kg-1.min-1, low-dose nimodipine, consisting of an initial bolus of 30 micrograms/kg at the time of EEG slowing, followed by 0.15 microgram.kg-1.min-1, an equal volume of vehicle solution, or 154 mmol/l NaCl. Animals receiving either low- or high-dose nimodipine had higher mortality, and increased brain damage compared with controls. Examination of the perfusion-fixed brains 1 week after recovery with glucose revealed that quantitated neuronal necrosis was worsened by nimodipine in the hippocampus, caudate nucleus and cerebral cortex. The present results in profound hypoglycaemia (accompanied by a flat EEG) contrast with the beneficial effect of nimodipine in brain ischaemia.

The Nordstrom's of medical practices

While managed care has been touted as potentially putting an end to the private practice of medicine, the area of elective surgery is in a position to thrive. Plastic surgery practices and surgicenters are ideally positioned to provide superior patient care, providing a smart blend of old-fashioned service and state-of-the-art surgical care. Coupled with a current interest in facility accreditation, private practices and surgicenters are poised to enjoy a bright future.

The plastic surgical nurse. Nurse specialist for the 1990s

In the preface to the Core Curriculum, editor Terri Goodman, RN, MA, CPSN, CNOR, eloquently describes plastic surgical nursing as "a dynamic specialty that is expanding rapidly in response to technology, creativity, and the increasing autonomy of both nurse and patient." She goes on to say that today's "plastic surgical nurse [is] a sensitive, skilled communicator [possessing] a broad knowledge base and the ability to apply principle." These are exciting times in which to be a nurse. Yes, the winds of change are blowing. Some see them as threatening the core of medical practice, that is, caring for patients. Others see them bringing opportunity, empowerment for nurse specialists, and freedom to reach new levels of professionalism. The specialty of plastic surgical nursing is proud to be a part of this exciting future.

Outpatient surgery center accreditation

The increase in outpatient surgery has spurred an interest in accreditation for ambulatory surgery centers. Several agencies accredit health care facilities, including the Joint Commission on the Accreditation of Healthcare Organizations (JCAHO). This article details one ambulatory surgery center's step-by-step actions toward obtaining JCAHO accreditation.

Munchausen syndrome: hospital hobo of the 1990s

Munchausen Syndrome is an unusual subset of symptoms experienced by patients who self-inflict artificial illness. Caring for Munchausen patients, who are frequently finding their way into plastic surgery practices, is very time consuming because they often fail to respond to standard modalities of treatment. They abuse the medical system by seeking care from one or more caregivers at the same time and appear to relish repeating expensive diagnostic procedures. Four case studies are presented in this article along with suggestions for treating these patients.

Brain protein kinase C assay using MARCKS substrate reveals no translocation due to profound insulin-induced hypoglycemia

Hypoglycemia sufficient to produce EEG isoelectricity or coma leads to neuronal death by an excitotoxic mechanism due to elevated extracellular levels of glutamate, aspartate and increased intracellular calcium. Since an elevated intracellular calcium concentration is known to translocate protein kinase C (PKC) from the cytosol to the membrane (a process thought to represent the in vivo activation of the enzyme), the objective of this investigation was to determine if calcium-dependent isoforms of PKC were translocated in specific brain regions of rats subjected to 40 min of insulin-induced hypoglycemic coma. The caudate nucleus and hippocampus (regions damaged by hypoglycemia showing extensive neuronal necrosis), and cerebellum (an undamaged, control region) of hypoglycemic rats were microdissected. Soluble and detergent (Triton X-100)-solubilized particulate fractions were partially purified by DEAE-Sephacel chromatography. PKC activity in both fractions was then measured using a novel assay based on the calcium- and lipid (phosphatidylserine and diolein)-dependent phosphorylation of the specific substrate myristoylated alanine rich C kinase substrate (MARCKS). The percentage distribution of PKC in the soluble and particulate (membrane-bound) fractions of all the brain regions from hypoglycemic rats was not significantly different from that in the control brains, indicating that 40 min of hypoglycemia does not result in PKC translocation as measured in subcellular fractions from brain tissue.

Medical waste management: implications for plastic surgery offices and surgicenters

This article focuses on how current rules and regulations impact on waste management in plastic surgery offices, and outpatient surgicenters. The suggestions provided are based on federal and state laws, OSHA requirements, JCAHO and AORN standards, and experience provided by members of ASPRSN.

Gas in the hepatic portal venous system. A diagnostic clue to an occult intra-abdominal abscess

Gas within the hepatic venous system on abdominal roentgenogram prompted exploratory laparotomy in a patient with repeated rigors and high fever following total hip replacement. Although the patient had no localizing abdominal symptoms or signs, an intra-abdominal abscess was found and cured by surgical drainage and antibiotics. Occult, life-threatening, but treatable abdominal disease may be detected by the unusual roentgenographic finding of portal venous gas.

Immunologic characterization of the mononuclear cell infiltrates in rheumatoid synovia, in rheumatoid nodules, and in lip biopsies from patients with Sjögren's syndrome

Two subcutaneous rheumatoid nodules and 8 rheumatoid synovia from patients with rheumatoid arthritis (RA); and 2 parotid glands, 1 "pseudolymphoma," and 6 lip biopsies from patients with Sjogren's syndrome (SS) were studied to identify mononuclear cells. The palisading mononuclear cells in subcutaneous nodules had a surface membrane receptor for complement. B lymphocytes surrounded by larger numbers of non-B lymphocytes were found in RA synovium and between salivary ducts of SS lip biopsies. A "pseudolymphoma" obtained from a patient with SS consisted primarily of B lymphocytes. The predominant mononuclear cell in rheumatoid synovia and salivary glands in patients with RA and SS do not have surface membrane receptors from complement and are thus probably T lymphocytes or null cells.

Association of polyarthritis, subcutaneous nodules, and pancreatic disease

A patient with nodular liquefying panniculitis, polyarthritis and an occult pancreatic neoplasm is described. The skin lesion was initially mistaken for erythema nodosum. Subcutaneous and synovial fluids demonstrated similar negatively birefringent, rectangular particles, lying in between fat globules. Serum lipase,although continuously elevated, did not fluctuate with disease activity. Biochemical evidence of lipolysis in either the synovial fluid or serum was not demonstrable. Immunologic mechanisms appeared not to be involved in the pathogensis of the panniculitis or the arthritis.

Diagnosis of sarcoidosis by lip biopsy of minor salivary glands

In two patients with bilateral parotid gland swelling of unknown etiology the diagnosis of sarcoidosis was established by lip biopsy of the minor salivary glands. This simple, innocuous biopsy procedure may prove useful in tissue documentation of sarcoidosis.