Determinants of neurological disease: Synthesis of systematic reviews

Systematic reviews were conducted to identify risk factors associated with the onset and progression of 14 neurological conditions, prioritized as a component of the National Population Health Study of Neurological Conditions. These systematic reviews provided a basis for evaluating the weight of evidence of evidence for risk factors for the onset and progression of the 14 individual neurological conditions considered. A number of risk factors associated with an increased risk of onset for more than one condition, including exposure to pesticides (associated with an increased risk of AD, amyotrophic lateral sclerosis, brain tumours, and PD; smoking (AD, MS); and infection (MS, Tourette syndrome). Coffee and tea intake was associated with a decreased risk of onset of both dystonia and PD. Further understanding of the etiology of priority neurological conditions will be helpful in focusing future research initiatives and in the development of interventions to reduce the burden associated with neurological conditions in Canada and internationally.

Do Biologics Protect Patients With Psoriasis From Myocardial Infarction? A Retrospective Cohort

BACKGROUND

Psoriasis is a chronic immune-mediated inflammatory disorder that affects approximately 2% to 3% of the population, which translates to 17 million in North America and Europe and approximately 170 million people worldwide. Although psoriasis can occur at any age, most cases develop before age 40 years. Some larger studies have noted bimodal age at onset with the first peak occurring at approximately age 30 years and the second peak at around 55 to 60 years, but most patients have a younger age of onset (15-30 years). Psoriasis is associated with multiple comorbidities, decreased quality of life, and decreased longevity of life. Two recent systematic reviews and a meta-analysis concluded that psoriasis patients are at increased risk of major adverse cardiovascular events. Multiple studies confirm that many of the comorbidities found in patients with psoriasis are also important risk factors for cardiovascular disease, stroke, diabetes mellitus, hypertension, hyperlipidemia, obesity, and metabolic syndrome.

METHODS

We conducted a retrospective cohort study using charts from a dermatology clinic combined with an administrative database of patients with moderate to severe psoriasis in Newfoundland and Labrador, Canada. We examined the role of clinical predictors (age of onset of psoriasis, age, sex, biologic use) in predicting incident myocardial infarction (MI).

RESULTS

Logistic regression revealed that age of onset (odds ratio [OR], 8.85; P = .005), advancing age (OR, 1.07; P < .0001), and being male (OR, 3.64; P = .018) were significant risk factors for the development of MI. Neither biologic therapy nor duration of biologic therapy were statistically significant risk factors for the development of MI. Our study found that in patients with psoriasis treated with biologics, there was a nonsignificant trend in reduced MI by 78% (relative risk, 0.18; 95% confidence interval, 0.24-1.34; P = .056).

CONCLUSION

Our study demonstrated a trend toward decreased MI in patients with moderate to severe psoriasis on biologics. Patients with an early age of onset of psoriasis (<25 years) were nearly 9 times more likely to have an MI. Clinicians should consider appropriate cardiovascular risk reduction strategies in patients with psoriasis.

Factors associated with the onset and progression of neurotrauma: A systematic review of systematic reviews and meta-analyses

Neurotrauma, including traumatic brain injury (TBI) and spinal cord injury (SCI), is a preventable condition that imposes an important burden on the Canadian society. In this study, the current evidence on risk factors for the onset and progression of neurotrauma is systematically reviewed and synthesized. Searches of the Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects (DARE), Medline and Medline in Process (via OVID), EMBASE and PsycINFO from inception to February 2013 were conducted to identify relevant systematic reviews and meta-analyses published in English or French. Two referees screened and assessed the quality of the studies using the AMSTAR tool. Thirty-two studies examined at least one risk factor for the onset of neurotrauma. Thirteen studies passed the quality assessment and the majority evaluated the impact of protective equipment in sports. Helmets effectively reduce TBI from bicycling, skiing, snowboarding, ice hockey and motorcycling. There was no evidence of a protective effect of helmets for SCI. No studies contributed evidence on risk factors for the onset of SCI. Of two studies examining risk factors for the progression of neurotrauma, only injury severity was found to be associated with poorer post-injury outcomes. Substantial evidence supports the use of helmets for the prevention of TBI in sports and motorcycling and face shields in ice hockey. Addressing bicycle helmet legislation across Canada may be an effective option for reducing TBI caused by bicycle accidents. Limited evidence on relevant risk factors for spinal cord injuries and neurotrauma progression was available.

Development of a decision-support tool for identifying the most suitable approach to achieve nitrate source determination

Numerous approaches have been suggested for differentiating point and diffuse sources of nitrate contamination, including nitrate stable isotopes, microbiological analyses, genetic markers and chemical markers. Each approach has its own strengths and limitations. As a result, the most appropriate approach to use largely depends upon the scenario and the context of the study. However, available data on nitrate source determination is highly fragmented and approach dependent, with very little if any interface between the different techniques. This makes it difficult for stakeholders to identify the most suitable approach to adopt in a specific scenario. Therefore, this paper examines the development and application of a decision-support tool to support environmental forensics studies for nitrate contamination. In particular, this tool can support policy makers, regulators and operators within the field in understanding the environmental hazards and processes resulting from nitrate contamination, and to implement appropriate actions for limiting the impacts that may arise from such contamination. The tool was developed using the IDEF0 modeling system, and evaluated by interviewing key stakeholders who suggested a number of important implications for practice.

Anomalous low-temperature proton conductivity enhancement in a novel protonic nanocomposite

A novel protonic ceramic composite is synthesized that comprises nanoscale nickel metal films at the grain boundaries of the proton-conducting ceramic, BaCe_0.7Zr_0.1Y_0.1Yb_0.1O_3−δ. Low-temperature proton conductivity improvements of up to 46× are observed.

The potential for a suite of isotope and chemical markers to differentiate sources of nitrate contamination: a review

Nitrate is naturally found within the environment as part of the nitrogen cycle. However, anthropogenic inputs have greatly increased nitrate loads within ground and surface waters. This has had a severe impact on aquatic ecosystems and has given rise to health considerations in humans and livestock. Therefore, the identification of nitrate sources is important in preserving water quality and achieving sustainability of our water resources. Nitrate sources can be determined based on the nitrate nitrogen (N) and oxygen (O) isotopic compositions (δ(15)N, δ(18)O). However, sewage and manure have overlapping δ(15)N and δ(18)O values making their differentiation on this basis problematic. The specific differentiation between sources of faecal contamination is of particular importance, because the risk to humans is usually considered higher from human faecal contamination (sewage) than from animal faecal contamination. This review summarises the current state of knowledge in using isotope tracers to differentiate various nitrate sources and identifies potential chemical tracers for differentiating sewage and manure. In particular, an in depth review of the current state of knowledge regarding the necessary considerations in using chemical markers, such as pharmaceuticals and food additives, to differentiate sewage and manure sources of nitrate contamination will be given, through an understanding of their use, occurrence and fate, in order to identify the most suitable potential chemical markers.

Kisspeptin synchronizes preovulatory surges in cyclical ewes and causes ovulation in seasonally acyclic ewes

We determined whether kisspeptin could be used to manipulate the gonadotropin axis and ovulation in sheep. First, a series of experiments was performed to determine the gonadotropic responses to different modes and doses of kisspeptin administration during the anestrous season using estradiol-treated ovariectomized ewes. We found that: 1) injections (iv) of doses as low as 6 nmol human C-terminal Kiss1 decapeptide elevate plasma LH and FSH levels, 2) murine C-terminal Kiss1 decapeptide was equipotent to human C-terminal Kiss1 decapeptide in terms of the release of LH or FSH, and 3) constant iv infusion of kisspeptin induced a sustained release of LH and FSH over a number of hours. During the breeding season and in progesterone-synchronized cyclical ewes, constant iv infusion of murine C-terminal Kiss1 decapeptide-10 (0.48 mumol/h over 8 h) was administered 30 h after withdrawal of a progesterone priming period, and surge responses in LH occurred within 2 h. Thus, the treatment synchronized preovulatory LH surges, whereas the surges in vehicle-infused controls were later and more widely dispersed. During the anestrous season, we conducted experiments to determine whether kisspeptin treatment could cause ovulation. Infusion (iv) of 12.4 nmol/h kisspeptin for either 30 or 48 h caused ovulation in more than 80% of kisspeptin-treated animals, whereas less than 20% of control animals ovulated. Our results indicate that systemic delivery of kisspeptin provides new strategies for the manipulation of the gonadotropin secretion and can cause ovulation in noncyclical females.

The development of novel flexible electrode arrays for the electrochemotherapy of solid tumour tissue. (Potential for endoscopic treatment of inaccessible cancers)

Therapeutic "electroporation" involves application of electric fields to target cells/tissues, thereby rendering their cell membranes transiently porous, thus making feasible the cellular uptake and efficacy of previously impermeant and ineffective therapeutic agents. The objectives of this research are a) the development of flexible electrode arrays for incorporation into microsystem endoscopic devices, and b) the assessment of their efficacy in delivering selected genetic and pharmaceutical anticancer therapies. Gold electrodes were fabricated on flexible polyimide substrates following predictive modeling and simulation of electric fields using FEMLAB software. Subsequent assessment of electroporation efficiency in-vitro involved 1) enumeration of viable tumour cells after delivery of electric pulses and exposure to low concentrations of bleomycin, otherwise known as electrochemotherapy 2) Efficacy of gene delivery by detection of emitted green fluorescence by cells after electroporation with the pEGFP plasmid and 3) In-vivo efficacy of electrochemotherapy in a variety of human solid tumour masses in nude mouse models (xenografts). The flexible electrode system was found to be successful for electrical delivery of plasmids and drugs in-vitro and in-vivo. We found in-vivo complete regression of prostate, colon, oesophageal, and renal cancers with reduced growth rates for fibrosarcoma and breast cell lines. These flexible electrodes are suitable for electrochemotherapy or gene therapy to solid tumours masses and may be fabricated for application to the treatment of some cancers in humans by transcutaneous or endoscopic delivery systems.

Quantitative bacillary response to treatment in Mycobacterium tuberculosis infected and M. africanum infected adults with pulmonary tuberculosis

Data regarding possible differences in microbiological response to therapy of disease caused by Mycobacterium tuberculosis and M. africanum are limited. Presenting clinical characteristics and sputum bacillary load during standard short-course chemotherapy in patients with newly-diagnosed pulmonary tuberculosis due to M. tuberculosis (n = 7) and M. africanum (n = 6) were compared. Changes in sputum bacillary load were measured using quantitative acid-fast bacilli smears, colony forming unit assay, and time until positive culture in the BACTEC radiometric system. Presentation and response to short course chemotherapy were comparable between patients infected with M. tuberculosis and those infected with M. africanum.

Quantitative sputum bacillary load during rifampin-containing short course chemotherapy in human immunodeficiency virus-infected and non-infected adults with pulmonary tuberculosis

SETTING

National Tuberculosis (TB) Treatment Centre, Mulago Hospital and Joint Clinical Research Centre, Kampala, Uganda.

OBJECTIVE

To compare the quantitative sputum bacillary load between TB patients infected with the human immunodeficiency virus (HIV) and those non-infected, during treatment with standard short course chemotherapy (SCC).

DESIGN

To compare clinical characteristics and quantitative sputum bacillary load as measured by quantitative acid-fast bacilli (AFB) smears, colony forming unit (cfu) assay and time until positive culture in the BACTEC radiometric liquid system between 14 HIV-infected and 22 non-HIV-infected adults with initial episodes of smear-positive pulmonary TB at baseline and during treatment with standard four-drug SCC.

RESULTS

Other than cavitation (P = 0.042) and adenopathy (P = 0.03), which were more common among non-HIV-infected and HIV-infected patients, respectively, there were no significant differences in baseline demographic, clinical, radiological and laboratory characteristics between the groups. Mean pretreatment sputum bacillary burden (6.5+/-0.51 log10 AFB/ml, 5.91+/-0.91 log10 cfu/ml and 1.8+/-1.7 days until positive BACTEC culture for HIV-infected patients and 6.32+/-0.85 log10 AFB/ml, 5.58+/-0.68 log10 cfu/ml and 1+/-1.2 days until positive BACTC culture for non-HIV-infected patients) were comparable between HIV-infected and non-HIV-infected patients. Clinical and bacteriological responses to standard SCC and treatment outcome did not differ between the groups.

CONCLUSION

Quantitative sputum bacillary load at baseline and during SCC did not differ significantly between HIV-infected and non-HIV-infected adults with initial episodes of smear-positive TB.

Determination of drug susceptibility and DNA fingerprint patterns of clinical isolates of Mycobacterium tuberculosis from Kampala, Uganda

OBJECTIVE

To ascertain the rate of initial drug resistance and transmission patterns of Mycobacterium tuberculosis in Kampala, Uganda.

SETTING

National Tuberculosis (TB) Treatment Centre, Mulago Hospital, Kampala, Uganda and Case Western Reserve University, Cleveland, Ohio, USA and McClellan Memorial Veterans Hospital, Little Rock, Arkansas, USA.

METHODS

Using a radiometric BACTEC 460 TB system, susceptibility of 215 M. tuberculosis isolates from previously untreated patients from Kampala, Uganda (age range, 17-48 years, mean, 28 years; 56% males and 69% human immunodeficiency virus (HIV)-seropositive) was determined for isoniazid, rifampin, streptomycin and ethambutol. Isolates from 73 patients, selected on the basis of geographical location, were tested for strain diversity or relatedness using the IS6110 DNA fingerprinting technique.

RESULTS

Resistance rates were as follows: isoniazid, 7.9% streptomycin, 6.1% rifampin, 1.4% and ethambutol 0.9%. Twelve per cent of the strains were resistant to at least one of the first line drugs tested and 4.7% were multiply resistant. There were no significant differences in resistance rates between patients with and without HIV infection. Using the number and size of DNA fragments containing IS6110, only three clusters of isolates with identical RFLP patterns were found out of the 73 isolates tested (8.2%). Each cluster contained two isolates. Three (4.1%) isolates had less than seven copies of IS6110.

CONCLUSION

This study shows that in Uganda initial drug resistance rates to anti-tuberculosis agents are low and similar to other sub-Saharan African countries and that multiple strains of M. tuberculosis have been transmitted within the community.

Antibiotic restriction does not alter endemic colonization with resistant gram-negative rods in a pediatric intensive care unit

OBJECTIVE

To test whether a ceftazidime restriction policy in a pediatric intensive care unit (ICU) could decrease the endemic rate of colonization with ceftazidime-resistant gram-negative bacilli.

DESIGN

Prospective, pre- vs. postintervention study.

SETTING

University hospital pediatric ICU.

PATIENTS

Consecutive children admitted to the pediatric ICU over a 19-mo period.

INTERVENTIONS

After an observation period in which antibiotic use was not controlled, ceftazidime was prohibited unless the patient's microbiological results indicated that the drug was necessary for cure. Aminoglycoside use was not regulated. The size of the endemic reservoir of ceftazidime- and tobramycin-resistant organisms was determined by daily nasopharyngeal and rectal swab specimens obtained on all admissions to the ICU.

MEASUREMENTS AND MAIN RESULTS

Despite a 96% reduction in ceftazidime use, the incidence density (number of isolates/100 patient-days) of ceftazidime-resistant organisms increased through the course of the study, from 1.57 to 2.16. The incidence density of tobramycin-resistant organisms was unchanged. Ceftazidime restriction resulted in a small but nonsignificant decrease in the proportion of ceftazidime-resistant organisms acquired late (beyond 72 hrs) in the patients' ICU course (56.5% vs. 45.9%). However, there was a more substantial decrease in the proportion of ceftazidime-resistant organisms derived from species known to harbor derepressible amp C beta-lactamases (68.2% vs. 45.9%, p < .05).

CONCLUSIONS

These data indicate that antibiotic restriction policies in an ICU fail to diminish the size of the endemic reservoir of antibiotic-resistant gram-negative rods, and suggest that such policies in the absence of broader efforts to limit antibiotic use will have little impact.

Lack of utility of the lysis-centrifugation blood culture method for detection of fungemia in immunocompromised cancer patients

We retrospectively compared the utility of a fungal isolation device (Isolator) versus conventional techniques for recovering fungal organisms from blood cultures obtained from neutropenic cancer patients. Positive cultures were deemed true pathogens, possible pathogens, or contaminants according to laboratory and clinical criteria. Fifty-three patients had 66 positive blood cultures for fungi, nine on multiple occasions. In 20 episodes true pathogens were recovered, 6 from broth medium alone, 4 from the Isolator system alone, and 10 from both systems. False-negative cultures were noted in 4 of 20 (20%) cases in which broth medium was used and in 6 of 20 (30%) cases in which the Isolator system was used. Possible pathogens were detected in 4 of 66 blood culture-positive cases. Forty-two positive cultures were considered contaminants, 1 collected from standard medium and 41 of 42 (98%) which grew only in Isolators. Eleven of 18 patients with true fungal infections expired as a result of infection, while 4 of 33 patients with a contaminant expired, none from a fungal cause. We do not advocate the routine use of Isolator tubes in the evaluation of the febrile, neutropenic patient due to the high rates of false positives and of contamination.

Coronary atherectomy: overview and implications for nursing

Coronary atherectomy, a new invasive procedure for the treatment of atherosclerotic heart disease, consists of the excision and removal of atherosclerotic tissue from coronary artery walls. This article provides current information on atherectomy, including its potential advantages over percutaneous transluminal coronary angioplasty (PTCA). Indications, limitations, medical research, and implications for nursing research are described. A case study is presented.

Chronic maxillary sinusitis associated with the mushroom Schizophyllum commune in a patient with AIDS

Invasive infection with fungi of the Basidiomycota (rusts, smuts, toadstools, mushrooms, and puffballs) is extremely rare. We report such an infection in a patient with human immunodeficiency virus disease who presented with chronic maxillary sinusitis associated with the mushroom Schizophyllum commune. The organism was isolated from the surgical drainage material, and septate hyphae were seen invading the maxillary submucosa. The limited literature on this subject is reviewed.

Absence of bacteremia with Mycobacterium avium-intracellulare in Ugandan patients with AIDS

Disseminated infection with Mycobacterium avium-intracellulare is the most common systemic bacterial infection in American patients with the acquired immunodeficiency syndrome. Blood cultures for mycobacteria were obtained from 50 severely ill Ugandan patients fulfilling the World Health Organization criteria for AIDS and considered late in the course of their illness; 98% had antibody to HIV by ELISA. All blood cultures were negative. These data suggest that disseminated infection with M. avium-intracellulare is infrequent in Ugandan patients with AIDS, if it occurs at all.

Invasive infection with Saccharomyces cerevisiae: report of three cases and review

Saccharomyces cerevisiae (brewer's or baker's yeast) is a common colonizer of human mucosal surfaces, but its role as a clinically important pathogen has been unclear. We report three cases of life-threatening invasive infection with S. cerevisiae resulting in pneumonia, liver abscess and sepsis, and disseminated infection with cardiac tamponade, respectively. A review of the English-language literature reveals 14 other cases of saccharomyces infection in humans. Severe immunosuppression, prolonged hospitalization, prior antibiotic therapy, and/or prosthetic cardiac valves are the settings where saccharomyces infection has been observed. Because Saccharomyces can be a common saprophytic contaminant, biopsy and pathologic confirmation of infection are often necessary for a definitive diagnosis. Amphotericin B is the treatment of choice for serious infections with this organism.