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Background: In aneurysms overall, a lower rate of recanalization in stent assisted coiling vs coiling alone has been observed without an increase in morbidity. This study aims to stratify and compare degree of occlusion outcome by treatment modalities. Secondarily, this study aims to stratify and compare postoperative adverse events. Methods: MEDLINE and EMBASE databases were searched. Study center were reviewed for inclusion. We performed meta-regressions, bias analysis and fail-safe N. We controlled for the quality of the studies. Results: 396 nonduplicated patients were separated into 4 groups: microsurgical, stent-assisted coiling, coiling, stent only. Stent-assisted coiling has lower rate of retreatment (17 vs 24%) and higher rehemorrhage (5% vs 3%) compared to coiling. Stent-assisted has higher rates of complete occlusion (55% vs 45%) and lower rate of residual aneurysm (15% vs 23%) compared to coiling. Comparative analyses were performed. Microsurgical remained the most morbid modality with the best rate of complete occlusion (93%) and lowest rehemorrhage (2%) and retreatment rate (5%). Conclusions: This is the first and largest meta-analysis focusing on patients treated for basilar apex aneurysm. To our knowledge, this is the first study to stratify and compare degree of occlusion per treatment modality. This study provides benchmark numbers to guide clinicians.
Objective: Relative to the vast literature that employs measures of decision-making (DM), rigorous examination of their psychometric properties is sparse. This study aimed to determine whether three measures of DM assess the same construct, and to measure invariance of this construct across relevant covariates. Method: Participants were 372 adolescents at risk of escalation in cannabis use. DM was assessed via four indices from the Cups Task, Game of Dice Task (GDT), and Iowa Gambling Task (IGT). We used confirmatory factor analysis to assess unidimensionality of the DM construct, and moderated nonlinear factor analysis (MNLFA) to examine its measurement invariance. Results: The unidimensional model of DM demonstrated good fit. MNLFA results revealed that sex influenced mean DM scores, such that boys had lower risk-taking behaviors. There was evidence of differential item functioning (DIF), such that IQ and age moderated the IGT intercept and GDT factor loading, respectively. Significant effects were retained in the final model, which produced participant-specific DM factor scores. These scores showed moderate stability over time. Conclusions: Indices from three DM tasks loaded significantly onto a single factor, suggesting that these DM tasks assess a single underlying construct. We suggest that this construct represents the ability to make optimal choices that maximize rewards in the presence of risk. Our final DM factor accounts for DIF caused by covariates, making it comparable across adolescents with different characteristics. (JINS, 2019, 25, 661–667)
Cannabis use has been linked to impairments in neuropsychological functioning across a large and continually expanding body of research. Yet insight into underlying causal relations remains limited due to the historically cross-sectional nature of studies in this area. Recently, however, studies have begun to use more informative design strategies to delineate these associations. The aim of this article is to provide a critical evaluation and review of research that uses longitudinal designs to examine the link between cannabis use and neuropsychological functioning. In summarizing the primary findings across these studies, this review suggests that cannabis use leads to neuropsychological decline. However, across most studies, these associations were modest, were present only for the group with the heaviest cannabis use, and were often attenuated (or no longer significant) after controlling for potential confounding variables. Future studies with neuropsychological data before and after initiation of cannabis use, along with careful measurement and control of “shared risk factors” between cannabis use and poorer neuropsychological outcomes, are needed to better understand who, and under what conditions, is most vulnerable to cannabis-associated neuropsychological decline. (JINS, 2017, 23, 893–902)
Boiling is the most common method of household water treatment in developing countries; however, it is not always effectively practised. We conducted a randomized controlled trial among 210 households to assess the effectiveness of water pasteurization and safe-storage interventions in reducing Escherichia coli contamination of household drinking water in a water-boiling population in rural Peru. Households were randomized to receive either a safe-storage container or a safe-storage container plus water pasteurization indicator or to a control group. During a 13-week follow-up period, households that received a safe-storage container and water pasteurization indicator did not have a significantly different prevalence of stored drinking-water contamination relative to the control group [prevalence ratio (PR) 1·18, 95% confidence interval (CI) 0·92–1·52]. Similarly, receipt of a safe-storage container alone had no effect on prevalence of contamination (PR 1·02, 95% CI 0·79–1·31). Although use of water pasteurization indicators and locally available storage containers did not increase the safety of household drinking water in this study, future research could illuminate factors that facilitate the effective use of these interventions to improve water quality and reduce the risk of waterborne disease in populations that boil drinking water.
Local models are given for the singularities that can appear on the trajectories ofgeneral motions of the plane with more than two degrees of freedom. Versal unfoldings of these model singularities give rise to computer-generated pictures describing the family of trajectories arising from small deformations of the tracing point, and determine the local structure of the bifurcation curves.
To investigate predictive factors of complete obliteration following treatment with linac-based stereotactic radiosurgery for intracerebral arteriovenous malformations.
Archived plans for 48 patients treated at the British Columbia Cancer Agency and who underwent post-treatment digital subtraction angiography to assess obliteration were studied. Actuarial estimates of obliteration were calculated using the Kaplan-Meier method. Univariate and multivariate Cox proportional hazards models were used for analysis of incidence of obliteration. Log-rank test was used to search for parameters associated with obliteration.
Complete nidus obliteration was achieved in 38/48 patients (79.2%). Actuarial rate of obliteration was 75.9% at 4 years (95% confidence interval 63.1%-88.6%). On univariate analysis, prescribed dose to the margin (p=0.002) and dose to isocentre (p=0.022) showed statistical significance. No parameters were significant in a multivariate model. According to the log-rank test, prescribed dose to the margin of >20 Gy (p=0.004) and dose to the isocentre of >25 Gy (p=0.004) were associated with obliteration.
Reported series in the literature suggest a number of different factors are predictive of complete obliteration of arteriovenous malformations following radiosurgery. However, differing definitions of volume and complete obliteration makes direct comparison between series difficult. This study demonstrates that complete obliteration of the nidus following linear accelerator-based stereotactic radiosurgery for arteriovenous malformations appears to be most closely related to the prescribed marginal dose. In particular, a marginal dose of >20Gy is strongly associated with obtaining complete obliteration of the nidus.
The mouse mutation hairy ears (Eh) originated in a neutron irradiation experiment at Oak Ridge National Laboratory. Subsequent linkage studies with Eh and other loci on Chr 15 suggested that it is associated with a chromosomal rearrangement that inhibits recombination since it shows tight linkage with several loci occupying the region extending from congenital goiter (cog) distal to caracul (ca). We report here (1) linkage experiments confirming this effect on recombination and (2) meiotic and mitotic cytological studies that confirm the presence of a chromosomal rearrangement. The data are consistent with the hypothesis of a paracentric inversion in the distal half of Chr 15. The effect of the inversion extends over a minimum of 30 cM, taking into account the genetic data and the cytologically determined chromosomal involvement extending to the region of the telomere.
Over the past 40 years there have been marked shifts in arable farmland management that are widely believed to have had a considerable impact on flowering plants and invertebrates and the small mammals and birds that rely upon them. It is not yet possible to predict the dynamics of plants and invertebrates either with past or future changes in farmland management. This study investigates whether a basic invertebrate classification, formed of broad trophic groups, can be used to describe interactions between invertebrates and their resource plants and evaluate management impacts for genetically modified, herbicide-tolerant (GMHT) and conventional herbicide management in both spring- and winter-sown oilseed rape. It is argued that the analyses validate trophic-based approaches for describing the dynamics of invertebrates in farmland and that linear models might be used to describe the changes in invertebrate trophic group abundance in farmland when driven by primary producer abundance or biomass and interactions between invertebrates themselves. The analyses indicate that invertebrate dynamics under GMHT management are not unique, but similar to conventional management occurring over different resource ranges, and that dynamics differed considerably between spring- and winter-sown oilseed rape. Thus, herbicide management was of much lower impact on trophic relationships than sowing date. Results indicate that invertebrate dynamics in oilseed rape are regulated by a combination of top-down and bottom-up trophic processes.
Objective: To define the anatomic characteristics of the congenitally malformed and severely stenotic aortic valve using trans-thoracic real time three-dimensional echocardiography, and to compare and contrast this with the valvar morphology as seen at surgery. Design: Prospective cross-sectional observational study Setting: Tertiary centre for paediatric cardiology Methods: All patients requiring aortic valvotomy between December 2003 and July 2004 were evaluated prior to surgery with three-dimensional echocardiography. Full volume loop images were acquired using the Phillips Sonos 7500 system. A single observer analysed the images using “Q lab 4.1” software. The details were then compared with operative findings. Results: We identified 8 consecutive patients, with a median age of 16 weeks, ranging from 1 day to 11 years, with median weight of 7.22 kilograms, ranging from 2.78 to 22 kilograms. The measured diameter of the valvar orifice, and the number of leaflets identified, corresponded closely with surgical assessment. The sites of fusion of the leaflets were correctly identified by the echocardiographic imaging in all cases. Fusion between the right and non-coronary leaflets was identified in half the patients. Dysplasia was observed in 3 patients, with 1 patient having nodules and 2 shown to have excrescences. At surgery, nodules were excised, and excrescences were trimmed. The dysplastic changes correlated well with operative findings, though statistically not significant. Conclusion: We recommend trans-thoracic real time three-dimensional echocardiography for the assessment of the congenitally malformed aortic valve, particularly to identify sites of fusion between leaflets and to measure the orificial diameter. The definition of nodularity, and the prognosis of nodules based on the mode of intervention, will need a comparative study of patients submitted to balloon dilation as well as those undergoing surgical valvotomy
The ability to recognise fear is impaired in people with damage to the
amygdala and, interestingly, in adult psychopathy. Here we confirm that
deficits in recognising fear exist in children with psychopathic traits. We
show for the first time that, as with patients with amygdala damage, this
deficit can be temporarily corrected by simply asking them to focus on the
eyes of other people. These data support models of psychopathy that
emphasise specific dysfunction of the amygdala and suggest an innovative
approach for intervening early in the development of psychopathy.
Medulloblastoma is the most common malignant central nervous system tumour in children but, in contrast, quite rare in adults. Hemispheric, rather than midline, cerebellar medulloblastomas are more common in older children and adults. We present the unusual case of a 71-year-old man who presented with a fourth ventricular mass that proved to be a medulloblastoma.
A 71-year-old man presented with progressive balance problems, slurred speech and double vision. A CT scan of the brain revealed a hyperattenuating, partially calcified, avidly enhancing mass within the fourth ventricle. Diffusion weighted MRI showed restricted diffusion within the mass. The patient underwent a midline suboccipital craniotomy and a subtotal resection was achieved.
Histological examination showed a densely cellular neoplasm composed of small cells with a tendency towards neuroblastic rosette formation. Most cells were strongly positive for neuron-specific enolase and synaptophysin. Ultrastructurally, tumour cells showed evidence of neuronal differentiation. These findings were consistent with a classical medulloblastoma.
Adult medulloblastoma should be considered in the differential diagnosis of a partially calcified hyperattenuating mass within the fourth ventricle.
Glutamate release from photoreceptor terminals is controlled by
voltage-dependent calcium channels (VDCCs). In humans, mutations in the
Cacna1f gene, encoding the α1F subunit of VDCCs,
underlie the incomplete form of X-linked congenital stationary night
blindness (CSNB2). These mutations impair synaptic transmission from rod
and cone photoreceptors to bipolar cells. Here, we report anatomical and
functional characterizations of the retina in the nob2 (no
b-wave 2) mouse, a naturally occurring mutant caused by a null
mutation in Cacna1f. Not surprisingly, the b-waves of
both the light- and dark-adapted electroretinogram are abnormal in
nob2 mice. The outer plexiform layer (OPL) is disorganized, with
extension of ectopic neurites through the outer nuclear layer that
originate from rod bipolar and horizontal cells, but not from
hyperpolarizing bipolar cells. These ectopic neurites continue to express
mGluR6, which is frequently associated with profiles that label with the
presynaptic marker Ribeye, indicating potential points of ectopic synapse
formation. However, the morphology of the presynaptic Ribeye-positive
profiles is abnormal. While cone pedicles are present their morphology
also appears compromised. Characterizations of visual responses in retinal
ganglion cells in vivo, under photopic conditions, demonstrate
that ON-center cells have a reduced dynamic range, although their basic
center-surround organization is retained; no alteration in the responses
of OFF-center cells was evident. These results indicate that nob2
mice are a valuable model in which to explore the pathophysiological
mechanisms associated with Cacna1f mutations causing CSNB2, and
the subsequent effects on visual information processing. Further, the
nob2 mouse represents a model system in which to define the
signals that guide synapse formation and/or maintenance in the
Biological invasions are a major environmental concern due to their negative impacts on biodiversity and economics. We determined the population sizes and habitat-abundance relationships of the three most successful invasive bird species in Singapore: the house crow Corvus splendens, white-vented myna Acridotheres javanicus and common myna A. tristis. Estimated population sizes of the three species between February 2000 and February 2001 were between 106 000-176 000, 122 000-155 000 and 20 000-29 000, respectively. Population size of the house crow grew dramatically (>30-fold) in the last 15-16 y while that of the white-vented and common myna declined. Habitat-abundance relationships suggest that house crows are highly dependent on anthropogenic food. Their abundance was also positively related to proximity to coast. The common myna associated closely with agricultural areas while the white-vented myna probably preferred urban greenery among residential buildings. Our study shows that the three invasive bird species associated with different aspects of human-modified environment.
Background. Female nurses appear to have an increased risk of suicide but the reasons are unknown.
Method. We have concluded a study of nurse suicides (N = 106) in England and Wales, including a psychological autopsy study (N = 42) and case–control comparison with living nurses (N = 84).
Results. Nearly three-quarters of the nurse suicides had previous contact with psychiatric services and almost half had been psychiatric in-patients in the past. There were particularly marked differences between the cases and controls for current psychiatric disorder (90·5% v. 7·1%, OR = 68·5), personality disorder (38·1% v. 1·2%, OR = 32), and history of deliberate self-harm (71·4% v. 2· 4%, OR = 58·5). Family background and social factors (especially concerning interpersonal relationships) also distinguished the two groups. Smoking and serious alcohol abuse were much more frequent in the suicides. There was some indication that while many of the suicides were in contact with psychiatric services, care may not have been optimal in some cases.
Conclusions. The most important strategies for suicide prevention in nurses are in prevention, detection and management of psychiatric disorders. In assessing suicide risk a history of DSH and the presence of comorbid psychiatric and personality disorders are particularly important.
Environmental conditions, both external to and within three shallow ponds of the McMurdo Ice Shelf, were measured over an annual cycle between January 1997 and January 1998. We combined this with a study of the response of the benthic microbial mat communities to the transition from summer conditions to winter freezing. Over the study period air temperature was above 0°C for a few days during summer. At this time pond temperatures were higher than air temperatures, with evidence of thermo-haline stratification. The shallow areas of ponds froze between late February and early March, with bottom waters in the deepest pond remaining unfrozen until early June. Minimum winter air temperatures were below −40°C. There was little evidence of freezing point depression due to freeze-concentration of solutes, except at the very bottom of ponds. In the most conductive pond investigated, the temperature of basal freezing was −4°C and conductivity did not exceed approximately 60 mS cm−1 immediately prior to freezing. Microbial mats remained photosynthetically active up to conductivities between 40 and 80 mS cm−1, and were able to acclimate to lowered irradiance associated with ice formation. Although photosynthesis and respiration were reduced by 11% and 40% respectively at temperatures of −2°C compared to 1°C, there was no difference in light harvesting efficiency. Results from this study suggest that light limitation of photosynthesis, or freezing, determine the growth season for the microbial communities, depending on depth.
Immunoelectron microscopy using the anti-pectin monoclonal
antibody JIM 7 confirmed earlier observations that
pectin degradation is a primary event in the process of host
cell wall breakdown during the development of
chocolate spot disease (causal agent: Botrytis fabae (Sard.))
broad bean. Close examination of infected and non-infected Vicia faba
leaves indicated a loss of JIM 7-labelling, and therefore, methyl-esterified
swollen walls of infected and contiguous epidermal cells. Modified
mesophyll walls also possessed less methyl-esterified pectin
than healthy walls. Enzymes which attack methyl-esterified
pectin appeared to be most active in
regions of host tissue close to sites of fungal infection.
Ultrastructural studies using the enzyme, cellobiohydrolase conjugated
to gold (CBH1-Au) revealed that the
cellulose microfibrils of outer epidermal walls of non-infected
V. faba leaf tissue were heavily masked by other
components of the plant cell wall. Such material was most probably
pectin because the cellulose microfibrils of
swollen epidermal and modified mesophyll walls of infected host
tissue were heavily labelled with CBH1-Au.
These results were confirmed by double-labelling studies using JIM 7
and CBH1-Au. At early stages of the
infection process, limited cellulose degradation was observed in infected
Double-labelling experiments using the monoclonal antibody BC-KH4
directed against Botrytis matrices and
a marker for the plant cell wall (JIM 7 or CBH1-Au) confirmed previous
observations that the fungal matrices
extended through modified host walls and degenerate cytoplasm. It is
suggested that the wall-modifying action of
the pectin-degrading enzymes produced during the infection process
might facilitate pervasion of matrix material
associated with the infection hyphae through host cell walls.
Possible role(s) of such matrix material during the
post-penetration processes of the V. faba–B. fabae
relationship are discussed.
Extracellular matrices associated with conidia and germ tubes of
Botrytis fabae (Sard.) sporelings grown on Vicia
faba L. leaves were clearly visualized by epi-fluorescence microscopy
following immunolabelling with the
monoclonal antibodies, BC-KH4 and BC-FD7-G9. These antibodies were
raised against surface washings of B. cinerea, are
directed against B. cinerea and B. fabae, and are
known to recognize carbohydrate epitopes on a
glycoprotein. Both BC-KH4 and BC-FD7-G9 also labelled matrix material
located at the surface of penetration
and infection hyphae inside the leaf tissue by epi-fluorescence microscopy.
Such matrix material was not visible by DIC microscopy.
Immunoelectron microscopy of B. fabae-infected leaf
tissue, prepared by progressive low-temperature
dehydration and embedding in acrylic resin, allowed further
investigation of the spatial distribution of the
antibody-binding sites. An abundance of BC-KH4 and BC-FD7-G9
antigenic sites were observed throughout the
fibrillar-like matrix material surrounding the germ tubes on the
leaf surface and the infection hyphae inside the
host cells. However, close examination of the V. faba–B.
interface inside the host tissue showed that this
fibrillar material extended some distance from the surface of
the infection hyphae and through the swollen
epidermal and mesophyll cell walls. Such fibrillar matrix material
is thought to be of fungal origin. The possible
role(s) of this matrix material in the infection process are discussed.
Double-immunolabelling studies using the BC-KH4 MAb and a
polyclonal antiserum directed against
oligosaccharides containing β-(1→3)-glucose were carried out
in order to localize and distinguish between the
fungal extracellular matrix material and translucent cell wall respectively.
This technique allowed a closer
examination of the interactions of the fungal matrix components with the
host walls and degenerate host
cytoplasm. Finally, inward curling of the leaf cuticle suggested that
mechanical pressure is involved in the penetration process.