Retinal Hemorrhage Associated with Human Granulocytic Anaplasmosis

This case report describes a 51-year-old female with presented to the emergency department with high-grade fever, headache, nausea, vomiting, dizziness, diffuse arthralgias, and new-onset worsened vision that had developed over 3 days.

Intravascular Lymphoma-Associated Stroke: A Systematic Review of Case Studies

Intravascular lymphoma (IVL) is an aggressive systemic large B-cell lymphoma that is a rare cause of stroke. The clinical characteristics of stroke associated with IVL remain underexplored, contributing to diagnostic complexities and a high mortality rate. This study endeavors to elucidate the salient clinical and investigative features of stroke linked to this condition. A systematic review was performed using the PubMed database from the incident to August 2023 including search categories for IVL and stroke. All studies, excluding review articles, were included in this study. There were 58 cases with a confirmed diagnosis of IVL associated with stroke, with a mean age of 62.9 ± 9.6 years (female 50%). Classical lateralizing stroke symptoms were noted in only 69% of cases. Other clinical syndromes included altered sensorium (31%), rapidly progressive cognitive impairment (23%), seizures (22%), and gait disturbances (19%). Common hematological abnormalities included elevated lactate dehydrogenase (LDH, 97%), erythrocyte sedimentation rate (ESR, 79%), C-reactive protein (CRP, 61%), interleukin-2, microglobulins, and cerebrospinal fluid (CSF) protein. CSF flow cytometry was not diagnostic, and cytology was mostly negative. The dynamic pattern for DWI/T2 lesions was predominant and primarily located in the subcortical regions. Diffuse background slowing (64%) was a major finding in the electroencephalogram. Seventy-one percent of cases died (n=45) mostly due to delayed diagnosis. Only 31% were treated with first-line R-CHOP (rituximab, cyclophosphamide, doxorubicin hydrochloride, vincristine, prednisone) chemotherapy, among whom 25% died. This study suggests that IVL-associated strokes carry a high mortality rate, largely due to challenges in timely diagnosis and therapy. Unlike classical stroke syndrome, key indicators to aid in early diagnosis include a clinical syndrome of multiple non-lateralizing neurological symptoms, dynamic MRI DWI/T2-lesions primarily located in subcortical regions, elevated serum LDH, ESR, CRP, interleukins, microglobulin, CSF protein, and CSF polymerase chain reaction analysis, apart from tissue examination. Larger studies should be performed to establish diagnostic and predictive scores.

Genetic considerations in cerebral small vessel diseases

Cerebral small vessel disease (CSVD) encompasses a broad clinical spectrum united by pathology of the small vessels of the brain. CSVD is commonly identified using brain magnetic resonance imaging with well characterized markers including covert infarcts, white matter hyperintensities, enlarged perivascular spaces, and cerebral microbleeds. The pathophysiology of CSVD is complex involving genetic determinants, environmental factors, and their interactions. While the role of vascular risk factors in CSVD is well known and its management is pivotal in mitigating the clinical effects, recent research has identified novel genetic factors involved in CSVD. Delineating genetic determinants can promote the understanding of the disease and suggest effective treatments and preventive measures of CSVD at the individual level. Here we review CSVD focusing on recent advances in the genetics of CSVD. The knowledge gained has advanced understanding of the pathophysiology of CSVD, offered promising early results that may improve subtype identification of small vessel strokes, has led to additional identification of mendelian forms of small vessel strokes, and is getting closer to influencing clinical care through pharmacogenetic studies.

Safety and efficacy of endovascular thrombectomy in patients with severe cerebral venous thrombosis: A meta-analysis

Background

Cerebral venous thrombosis (CVT) is a rare thrombotic condition which is traditionally treated with anti-coagulation therapy. Subsets of patients with severe CVT have been treated with endovascular thrombectomy (EVT). Despite the high estimated mortality associated with severe CVT, there has been only one randomized control trial done regarding safety and efficacy of EVT in severe CVT compared to standard medical management. Evidence in this area is lacking.

Objective

The aim of this systematic review is to analyze all existing literature and generate robust information regarding the role of EVT in the management of patients with severe CVT.

Methods

This systematic review and meta-analysis followed PRISMA guideline. PubMed, Embase, Google Scholar, and CNKI were searched for eligible studies from 2007 to 2021. Safety and efficacy of EVT were evaluated by meta-analyzing recanalization status, the good functional outcome at follow-up, recurrent CVT, new hematoma. A pooled proportion with a 95% confidence interval was derived from a meta-analysis of various outcomes (CI).

Results

A total of 33 studies comprising 610 patients treated with EVT were included for analysis which comprised one randomized control trial, one prospective study and 31 retrospective studies. Based on pooled data, 85% of patients had good functional outcome, 62% had complete recanalization, 5% had all-cause mortality, and 3% had catheter related complications. The efficacy outcomes in this analysis had a significant heterogeneity and a subgroup analysis was also done to explain these findings. The minimum time of follow up was 3 months and varied EVT techniques were used across the studies.

Conclusion

This meta-analysis suggests EVT may be safe and efficacious in treating patients with severe CVT.

Registration

Our protocol was registered with PROSPERO: International prospective register of systematic reviews with the registration number CRD42021254760.

Low-dose alteplase for the management of acute ischemic stroke in South Asians: A systematic review on cost, efficacy and safety

INTRODUCTION

South Asia is responsible for more than 40% of the stroke burden and stroke mortality in the developing world. South Asia, which is home to one-fourth of the world's population, is the most densely populated and one of the poorest regions. The majority of patients in this region are unable to afford intravenous thrombolysis (IVT) for acute ischemic stroke (AIS). If low-dose alteplase proves effective and safe in South Asians, it may be a more cost-effective treatment option.

METHODS

The study was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and meta-Analyses) guideline. Researchers searched PubMed, EMBASE, and Google Scholar for English literature from 2005 to 2021. END, ENI, good functional outcome, SICH, and all-cause mortality were used to assess efficacy and safety.

RESULTS

In the low-dose alteplase treated patients, different studies reported 32 to 57% ENI 24 h after IVT, and 7% to 9.7% END. At 3 months follow-up, good functional outcome was achieved by 48%-76.92% of low-dose alteplase treated patients. SICH rates ranged from 0% to 16.6% across studies. Asymptomatic ICH occurred in 5-14% of patients. The mortality rate in all included studies varied from none to 25%.

CONCLUSION

Our systematic review demonstrates that the use of low-dose alteplase for AIS in the South Asians offer comparable efficacy and reduced risk of SICH at a significantly lower cost than standard alteplase dose. Future well-randomized clinical trials are necessary to validate the findings of our study.

C-reactive protein levels in patients with amyotrophic lateral sclerosis: A systematic review

INTRODUCTION

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease affecting cortical and spinal motor neurons. There is a lack of optimal biomarkers to diagnose and prognosticate the ALS patients. C-reactive protein (CRP), an inflammatory marker, has shown promising results in ALS patients.

MATERIALS AND METHODS

PubMed, Embase, and Google Scholar databases were searched from 2000 to June 1, 2021 for suitable studies showing the relationship between CRP and ALS. The concentration of CRP levels was assessed between ALS patients and controls. Further, end outcomes like ALS functional rating scale (ALSFRS-R), survival status, and mortality risks were assessed in relation to CRP levels.

RESULTS

Eleven studies including five case-control, five cohorts, and one randomized control study were assessed. There were 2785 ALS patients and 3446 healthy controls. A significant increment in CRP levels among ALS patients in comparison with healthy controls were seen in most of the studies. ALSFRS-R and disease progression were found to be significantly correlated with CRP levels. Overall accuracy of CRP in CSF was 62% described in a single study.

CONCLUSION

Although CRP has shown promise as a prognostic biomarker, extensive cohort studies are required to assess its prognostic value and accuracy in diagnosing ALS taking into account the confounding factors.

Assessment of computed tomography perfusion RAPID estimated core volume accuracy in patients following thrombectomy

Background: Computed Tomography Perfusion (CTP) maps ischemic core volume (CV) and penumbra following a stroke; however, its accuracy in early symptom onset is not well studied. We compared the accuracy of CTP RAPID estimated CV with diffusion weighted imaging (DWI) infarct volume (IV) in patients following thrombectomy. Methods: Charts of anterior circulation large vessel occlusion post-thrombectomy cases with thrombolysis in cerebral infarction (TICI) 2b/3 reperfusion from 2017 to 2019 were reviewed. CTP time was dichotomized as 0-3 hours and ≥ 3 hours from the last known normal (LKN) cognition. The volumetric difference (VD), defined as DWI IV minus CTP CV, core volume overestimation (CVO), defined as CTP CV minus DWI IV and Alberta stroke programme early CT score (ASPECTS) were calculated. Large CV was defined as ≥ 50 ml CV. Modified Rankin Score (mRS) at 90 days were reviewed. We performed independent sample t-test and Spearman correlation coefficient test. Results: Total cases (n) were 61. In < 3 hours window from LKN (n = 27), the mean VD was 58.3 ± 0.1 ml (P = 0.990) and CVO (n = 11; 40.7%) was 39.6 ± 35.7 ml (P = 0.008). Mean large CV (n = 8) was 78.3 ± 25.4 ml with median ASPECTS of 8 [interquartile range (IQR) = 6.5-9.0] and median mRS at 90 days of 2 (IQR = 0.8-3.3). In ≥ 3 hours window from LKN (n = 34), CVO (n = 5) was uncommon and large CV had median mRS at 90 days of 5 (IQR = 4.0-6.0). Conclusion: CTP more frequently overestimates CV in patients who are < 3 hours from LKN. The treated patients with large CV in < 3 hours and > 3 hours had good and poor functional outcomes, respectively.

Safety and efficacy of Direct Oral Anticoagulants in cerebral venous thrombosis: A meta-analysis

Cerebral venous thrombosis (CVT) is caused by partial or complete occlusion of the major cerebral venous sinuses or the smaller feeding cortical veins which predispose to the risk of venous infarction and hemorrhage. Current guidelines recommend treating CVT with either low-molecular-weight heparin (LMWH) or unfractionated heparin (UFH) followed by an oral vitamin K antagonist (VKA) for 3-12 months. Direct oral anticoagulants (DOACs) have already established benefit over warfarin as a long-term treatment of symptomatic venous thromboembolic disorder like deep vein thrombosis (DVT), and pulmonary embolism (PE) given its equal efficacy and better safety profile. The benefit of DOACs over warfarin as a long-term anticoagulation for CVT has likewise been extensively studied, yet it has not been approved as first-line therapy in the current practice. We therefore performed a systematic review and meta-analysis of relevant studies to generate robust evidence regarding the safety and efficacy of DOACs in CVT. This meta-analysis demonstrates that the use of DOACs in CVT has similar efficacy and safety compared to VKAs with better recanalization rate.

Systolic blood pressure variability following endovascular thrombectomy and clinical outcome in acute ischemic stroke: A meta-analysis

Blood pressure variability (BPV) has been linked with the outcome of acute ischemic stroke (AIS) after endovascular thrombectomy (EVT). However, the association of the stroke outcome with specific short-term BPV parameters is unclear. We did a systematic literature search for studies published from January 2010 to September 2020. Eligibility criteria included studies with (1) AIS patients treated with EVT with or without thrombolysis; and (2) analysis of the association between short-term systolic BPV parameter and clinical outcomes. Systolic BPV parameters included standard deviation (SD), coefficient of Variation (CoV), successive Variation (SV), and Variation independent of mean. A total of 11 studies were meta-analyzed, comprising 3520 patients who underwent EVT. Lower odds of achieving good functional outcome at 3 months; that is, modified Rankin Scale (mRS) score ≤2 was associated with SD (OR, 0.854; p = .02), CoV (OR, 0.572; p = .04), SV (OR 0.41; p = .00) of systolic blood pressure (SBP). Likewise, higher odds of one-point increase in mRS score was associated with SD (OR 1.42; p = .03), CoV (OR 1.464; p = .00) and SV (OR 2.605; p = .00) of SBP. However, high BPV was not associated with symptomatic intracranial hemorrhage and all-cause mortality at 90 days. The association of BPV and early neurological deterioration was inconclusive. Based on the available studies, short-term systolic BPV is indicative of the clinical outcome of patients following EVT in AIS. Further research should focus on personalized blood pressure management strategies, rather than a one-size-fits-all approach.

Isolated Agenesis of Septum Pellucidum and Adult-Onset Seizure Tendency With Eye Closure Sensitivity

Septum pellucidum is a thin midline membrane that separates the anterior horns of the lateral ventricle. Agenesis of septum pellucidum (ASP) is considered a continuum of forebrain maldevelopment. Isolated ASP is a rare radiographic finding of unclear significance. We report a case of a 42-year-old male with ASP who presented with a new-onset seizure and eye closure sensitivity seen in the electroencephalogram. Magnetic resonance imaging of the brain confirmed the ASP. In the absence of data about the association between seizure and ASP, further studies are needed to determine its significance.

Facial Diplegia with Preserved Reflexes: An Unusual Case of Anti-GD1b Antibody Associated Guillain-Barré Syndrome

Anti-ganglioside D1b (GD1b) Immunoglobulin G (IgG) positive Guillain-Barré Syndrome (GBS) is rare and usually presents with acute sensory or cerebellar ataxia, ascending paralysis, and loss of deep tendon reflexes (DTRs). A 19-year-old female individual with recent Influenza A infection had an acute onset of facial diplegia and minimal leg weakness with preserved DTRs. Cerebrospinal fluid analysis showed albuminocytologic dissociation with positive serum anti-GD1b IgG antibody (52 IV; reference range 0-50). Magnetic resonance imaging of the cervical spine showed nerve root enhancement. Following intravenous immunoglobulin therapy and subsequent physiotherapy, the patient reached the nadir of leg weakness by one month and had complete motor recovery after one year. Sensory ataxia was observed in the fourth month of the illness, which subsided by eight months. DTRs were normal throughout the course of the disease. This case showed an unusual evolution of GBS with a positive anti-GD1b antibody presenting with acute facial diplegia, normal DTR and delayed sensory ataxia.

New-Onset Seizure With Possible Limbic Encephalitis in a Patient With COVID-19 Infection: A Case Report and Review

With the outbreak of COVID-19 (coronavirus disease 2019) as a global pandemic, various of its neurological manifestations have been reported. We report a case of a 54-year-old male with new-onset seizure who tested positive for severe acute respiratory syndrome coronavirus 2 from a nasopharyngeal swab sample. Investigative findings, which included contrast-enhancing right posterior temporal lobe T2-hyperintensity on brain magnetic resonance imaging, right-sided lateralized periodic discharges on the electroencephalogram, and elevated protein level on cerebrospinal fluid analysis, supported the diagnosis of possible encephalitis from COVID-19 infection. The findings in this case are placed in the context of the existing literature.

Abstract P362: A Volumetric Comparison of Computed Tomography Perfusion Rapid Core Volume in Different Time Frames With Diffusion-Weighted Imaging Infarct Volume in the Post-Thrombectomy Patients After Large Vessel Occlusion

Introduction: The Computed Tomography Perfusion (CTP) RAPID software is widely used for the patient selection for mechanical thrombectomy (MT) after anterior circulation large vessel occlusion (LVO). There is a notion that it overestimates the core volume (CV) in an earlier time frame from symptom onset. We compared the accuracy of CTP RAPID estimated CV in different time frames with diffusion weighted imaging (DWI) infarct volume (IV).

Method: A retrospective data review of patients who underwent MT for anterior circulation LVO with TICI 2b/3 reperfusion from 2017 to 2019 was done. Patients with baseline CTP and follow up 36-hour MRI was included. Patients with parenchymal hematoma, graded as per ECASS II classification were excluded. CTP time was dichotomized as 0-3 hours (hrs) and >3 hrs from symptom onset. DWI IV was calculated by ABC/2 formula. The volumetric difference (VD), defined as DWI IV minus CTP CV, core volume overestimation (CVO), defined as CTP CV minus DWI IV and CT ASPECTS was calculated. Large CV was defined as >50 ml CV. Standard descriptive statistics and independent sample T-test were used as statistical tools.

Result: Total MT cases (n) were 61. Mean age (y.o) was 66 (SD 13.9) (male 57.4%). In < 3 hrs from symptom onset (n 27), mean CTP CV was 38.8 ml (SD 39.8), DWI IV was 39.6 ml (SD 51.4), VD was 0.9 ml (SD 55.2) (p 0.945) and CVO (n 11) was 39.6 ml (SD 35.7) (p 0.008). Mean large CV (n 8) was 78.3 ml (SD 25.4) with median CT ASPECTS of 8 (IQR 6.5-9) and median mRS at discharge 2 (IQR 0.8- 3.3). In >3 hrs from symptom onset (n 34), mean CTP CV was 28.81 ml (SD 47.4), DWI IV was 75.3 ml (SD 69.5), VD was 46.5 ml (SD 61.8) (p 0.002) and CVO (n 5) was 25.2 ml (SD 41.27) (p 0.60). Mean large CV (n 5) was 116.8 ml (SD 75.3) with median CT ASPECTS of 6 (IQR 5-7) and median mRS at discharge 5 (IQR 4- 6).

Conclusion: Overestimated core volume on CTP was seen in more than one third cases within 3 hours from symptom onset. Large CV estimated within this time frame had higher CT ASPECTS and good functional outcome at discharge.

Gasperini Syndrome: A Case Report and Systematic Review and Proposing a New Definition

Gasperini syndrome (GS), a rare brainstem syndrome, is featured by ipsilateral cranial nerves (CN) V–VIII dysfunction with contralateral hemibody hypoesthesia. While there have been 18 reported cases, the GS definition remains ambiguous. We report a new case and reviewed the clinical features of this syndrome from all published reports to propose a new definition. A 57-year-old man with acute brainstem stroke had right CN V–VIII and XII palsies, left body hypoesthesia and ataxia. Brain MRI showed an acute stroke in the right caudal pons and bilateral cerebellum. After a systematic review, we classified the clinical manifestations into core and associate features based on the frequencies of occurring neurological deficits. We propose that a definitive GS requires the presence of ipsilateral CN VI and VII palsies, plus one or more of the other three core features (ipsilateral CN V, VIII palsies and contralateral hemibody hemihypalgesia). Additionally, GS, similar to Wallenberg's syndrome, represents a spectrum that can have other associated neurological features. The revised definition presented in this study may enlighten physicians with the immediate recognition of the syndrome and help improve clinical localization of the lesions and its management.

A Case of Isolated Dysarthria in a COVID-19 Infected Stroke Patient: A Nondisabling Neurological Symptom With Grave Prognosis

Isolated dysarthria is a speech abnormality characterized by slurring without any language dysfunction, or other neurological deficits. In an acute setting, it is commonly associated with stroke. In the context of social distancing during the current corona virus disease 2019 (COVID-19) pandemic, nondisabling symptoms such as isolated dysarthria can delay a patient's perception to seek immediate medical care. We present a rare case of isolated dysarthria in a COVID-19 infected stroke patient with a grave prognosis. A 79-year-old African American male presented with isolated dysarthria that manifested two days prior to his hospital visit. The dysarthria assessment showed impaired articulation, phonation, and prosody. Other neurological examinations were normal. He tested positive for the COVID-19 infection. His pulmonary CT scan showed bilateral ground glass opacities. An electrocardiogram showed atrial fibrillation (AF). Brain MRI revealed a punctate acute infarction in the left frontal lobe. Initially, he was treated with IV anticoagulation, oral beta-blocker, azithromycin and hydroxychloroquine, but he dramatically deteriorated within a week exhibiting a highly elevated cytokine level eventually resulting in multi-system organ failure. Despite aggressive treatment with steroids, tocilizumab and other supportive measures, the patient died of cardiac arrest. Our case highlights that acute stroke could manifest as an isolated dysarthria, which is an indicator of increased severity and high mortality with COVID-19 infection. Public awareness about the stroke symptom awareness should be emphasized. 

Neurological Manifestations Associated with Synthetic Cannabinoid Use- A Case Series

Background:

Synthetic Cannabinoid (SC) use has emerged as a growing public health threat in the United States. Several unexpected cases, presenting with a constellation of unrelated symptoms, but all having toxicity linked to SC use, have been reported in the last decade (2010-2019).

Methods:

We report a cluster of several independent cases where patients were admitted having different neurological manifestations. Extensive and expensive work-ups were performed. Upon further inspection, extended toxicology screens were found to be positive for SC metabolites.

Results:

It is alarming to observe that several reports highlight an increase in the varied and significant morbidity associated after SC use. Various SC compositions have been synthesized and distributed, with new molecules being generated at a staggering rate leading to unexpected manifestations.

Conclusion:

Young people are the most frequent users owing to its recreational effects, its easy accessibility, lower cost and difficulty in being detected in the urine by routine drug screens. From a hospital quality improvement perspective, efforts to characterize the presence of newly generated SC molecules and establish more accessible in-house screening methods will be a starting step in reducing the associated cost-burden. This will also minimize the unnecessary invasive procedures performed on a specific patient. From a socioeconomic viewpoint, solid and systematic crosstalk with increased recognition and reporting mechanism between the healthcare staff and public health personnel is strongly warranted to support state and federal regulatory efforts in combating this ongoing SC epidemic.

Reoccurrence of Stroke in a Patient With Peri-Device Leak of WATCHMAN Device

Atrial fibrillation is the leading cause of cardioembolic stroke, with emboli most commonly originating from the left atrial appendage. We report the case of a 71-year-old male with left atrial appendage closure via implantation of the WATCHMAN device, due to possible anticoagulation therapy failure and increased bleeding risk, following a stroke. Following a new stroke over a year later, a 1.8-mm peri-device leak was observed. Surgical records noted a minimal (<5 mm jet flow) peri-device leak after the installation, which was considered successful WATCHMAN implantation per protocol. This case highlights the persistent risk of cardioembolic stroke in patients with nonvalvular atrial fibrillation despite device implantation and questions the significance of peri-device leak and further management with anticoagulation for recurrent stroke.

Binder-free Sn–Si heterostructure films for high capacity Li-ion batteries

This study fabricated and demonstrated a functional, stable electrode structure for a high capacity Li-ion battery (LIB) anode. Effective performance is assessed in terms of reversible lithiation for a significant number of charge–discharge cycles to 80% of initial capacity. The materials selected for this study are silicon and tin and are co-deposited using an advanced manufacturing technique (plasma-enhanced chemical vapour deposition), shown to be a scalable process that can facilitate film growth on 3D substrates. Uniform and hybrid crystalline–amorphous Si nanowire (SiNW) growth is achieved via a vapour–liquid–solid mechanism using a Sn metal catalyst. SiNWs of less than 300 nm diameter are known to be less susceptible to fracture and when grown this way have direct electrical conductivity to the current collector, with sufficient room for expansion. Electrochemical characterisation shows stable cycling at capacities of 1400 mA h g⁻¹ (>4 × the capacity limit of graphite). This hybrid system demonstrates promising electrochemical performance, can be grown at large scale and has also been successfully grown on flexible carbon paper current collectors. These findings will have impact on the development of flexible batteries and wearable energy storage.

This study fabricated and demonstrated a functional, stable electrode structure for a high capacity Li-ion battery (LIB) anode.

Towards High Capacity Li-ion Batteries Based on Silicon-Graphene Composite Anodes and Sub-micron V-doped LiFePO4 Cathodes

Lithium iron phosphate, LiFePO₄ (LFP) has demonstrated promising performance as a cathode material in lithium ion batteries (LIBs), by overcoming the rate performance issues from limited electronic conductivity. Nano-sized vanadium-doped LFP (V-LFP) was synthesized using a continuous hydrothermal process using supercritical water as a reagent. The atomic % of dopant determined the particle shape. 5 at. % gave mixed plate and rod-like morphology, showing optimal electrochemical performance and good rate properties vs. Li. Specific capacities of >160 mAh g⁻¹ were achieved. In order to increase the capacity of a full cell, V-LFP was cycled against an inexpensive micron-sized metallurgical grade Si-containing anode. This electrode was capable of reversible capacities of approximately 2000 mAh g⁻¹ for over ¹50 cycles vs. Li, with improved performance resulting from the incorporation of few layer graphene (FLG) to enhance conductivity, tensile behaviour and thus, the composite stability. The cathode material synthesis and electrode formulation are scalable, inexpensive and are suitable for the fabrication of larger format cells suited to grid and transport applications.

Studies on crossover-specific mutants and the distribution of crossing over in Drosophila females

In Drosophila females, the majority of recombination events do not become crossovers and those that do occur are nonrandomly distributed. Furthermore, a group of Drosophila mutants specifically reduce crossing over, suggesting that crossovers depend on different gene products than noncrossovers. In mei-218 mutants, crossing over is reduced by approximately 90% while noncrossovers and the initiation of recombination remain unchanged. Importantly, the residual crossovers have a more random distribution than wild-type. It has been proposed that mei-218 has a role in establishing the crossover distribution by determining which recombination sites become crossovers. Surprisingly, a diverse group of genes, including those required for double strand break (DSB) formation or repair, have an effect on crossover distribution. Not all of these mutants, however, have a crossover-specific defect like mei-218 and it is not understood why some crossover-defective mutants alter the distribution of crossovers. Intragenic recombination experiments suggest that mei-218 is required for a molecular transition of the recombination intermediate late in the DSB repair pathway. We propose that the changes in crossover distribution in some crossover-defective mutants are a secondary consequence of the crossover reductions. This may be the activation of a regulatory system that ensures at least one crossover per chromosome, and which compensates for an absence of crossovers by attempting to generate them at random locations.

An evaluation of resin-ionomers to prevent coronal microleakage in endodontically treated teeth

While a gutta-percha system is most commonly used by practitioners for canal obturation, there is no agreement on how best to close the chamber of an endodontically treated tooth. Some materials used in restorative dentistry may have endodontic applications. Restorative materials of particular interest to endodontists are those used as subgingival restorations. Their properties include insolubility in oral fluids, adhesiveness, dual-cure capabilities, radiopacity, hardness and fluoride release, low cure shrinkage and a low coefficient of thermal expansion. The purpose of this in vitro study was to test three products that could be used to seal pulp chambers of endodontically treated teeth to prevent bacterial infiltration. A bacteriological assay system was used to determine the efficacy of three commercially available restorative materials to prevent penetration of Streptococcus salivarius from the pulp chambers into the prepared canals. The materials evaluated were: Geristore two-paste system with Tenure Quik with fluoride, Dispersalloy with Tenure Quik with fluoride, and Marathon posterior composite with Tenure Quik with fluoride. During the sixty days of the study, the analysis indicated that the Geristore two-paste system with Tenure Quik with fluoride provided a statistically significant improved seal when compared to the Marathon posterior composite and Dispersalloy amalgam with Tenure Quik with fluoride.

Amiodarone and cyclophosphamide: potential for enhanced lung toxicity

Antineoplastic therapy can be associated with drug-induced lung toxicity. With the increasing use of amiodarone for cardiac dysrhythmias there is an increasing possibility of its combined use with chemotherapies for various malignancies. We report a patient on long-term amiodarone who developed biopsy-proven drug-induced lung toxicity after receiving high-dose cyclophosphamide, at a time-frame much shorter than would have been predicted with cyclophosphamide alone. The potential for enhanced lung toxicity secondary to combination of amiodarone and cyclophosphamide is discussed.

Breast health practices and South Asian women

Breast cancer is an important women's health issue in all communities. To detect breast cancer early, all women should practise monthly breast self-examination, have regular clinical breast examinations and attend mammography screening at suggested intervals. Participation in these breast health practices is influenced by a wide variety of factors, including how women define health and health practices, priorities in women's lives and their explanations of the causes of diseases such as cancer.

South Asian womens' views on the causes of breast cancer: images and explanations

Using ethnoscience methods, interviews with 50 South Asian women living in Western Canada were conducted and analyzed to explore explanations and images of breast cancer. Embedded in the women's stories of breast cancer were distinctive, often vivid and fear-provoking images of abnormal growth. Explanations about the causes of breast cancer involved five domains of belief. The first domain was of a physical nature and centred on damage to the breast. A second domain of explanations, 'can catch it,' focused on the way this disease could be spread to others. Other women attributed breast cancer to the ways women could 'bring it upon yourself,' often linking a negative lifestyle with the development of cancer. Many women attributed cancer to being 'in the hands of others,' explaining the cancer was caused by careless words, curses or divine power. Finally, breast cancer was seen as something that could be passed down in the family. The taxonomy developed in this study provides a useful framework for understanding the explanations that might underlie women's health-seeking behaviours and for developing culturally suitable counseling strategies.

Beliefs related to breast health practices: the perceptions of South Asian women living in Canada

Breast cancer is becoming a major concern for many South Asian women. Clinical observations of women from a South Asian community living in Canada revealed an under use of early detection strategies. The purpose of this qualitative ethnoscience study was to examine breast health practices from the perspective of South Asian women to provide a foundation for the development of culturally suitable breast health services for this group. Open-ended interviews were conducted with a convenience sample of 50 South Asian women over the age of 30 who had not been diagnosed with breast cancer. Adequate representation of the main religious groups (i.e. Sikh, Hindu, Muslim and Christian) was ensured through sampling techniques. Analysis of translated interviews involved identification of themes and the development of a taxonomy to represent relationships among emerging cultural themes and domains. Four central domains of beliefs related to breast health practices were identified: beliefs about a woman's calling, beliefs about cancer, beliefs about taking care of your breasts and beliefs about accessing services. These beliefs hold important implications for how health promotion strategies should be structured and offered, In particular, attention must be paid to the language that is used to talk about breast cancer, the importance of the role of the family in women's health decisions and traditions related to using narratives to share information and advice.

Comparison of 3 different doses of budesonide and placebo on the early asthmatic response to inhaled allergen

BACKGROUND

A simple laboratory method to evaluate relative potency of inhaled corticosteroids in asthma would be valuable. Single-dose studies with the allergen-induced late asthmatic response have failed to show a useful dose-response relationship. Treatment for several days with inhaled corticosteroids will also inhibit the allergen-induced early asthmatic response.

METHODS

Twelve atopic asthmatic subjects were studied during a season when no medications were required except ipratropium bromide as needed. These subjects had positive allergen and methacholine inhalation tests and FEV1 greater than 70% of predicted value. A double-blind, randomized, cross-over study compared placebo and budesonide 100, 200, and 400 microg administered by means of Turbuhaler twice daily for 7 days with 6-day washout periods. Methacholine PC20 was measured before and after 6 days of treatment, and allergen PC15 was measured after 7 days of treatment.

RESULTS

The allergen PC15 (n = 11) was significantly larger (P = .0001) for all doses of budesonide compared with placebo, but there was no significant difference between the 3 doses of budesonide, and no dose response was demonstrated. The methacholine PC20 was significantly larger after all budesonide treatments compared with placebo (P = .024), but there was no difference between the 3 doses. There was a progressive increase in the allergen PC15 chronologically (sequence effect) that was not explained by improvement in FEV1 or airway responsiveness; sequence effects were not seen for FEV1 or for pretreatment or posttreatment methacholine PC20. Statistical adjustment for sequence effect did not alter allergen PC15 statistics.

CONCLUSION

A 7-day course of budesonide administered by means of Turbuhaler at 200, 400, or 800 microg per day provided marked and significant inhibition of the allergen-induced early asthmatic response compared with placebo. There was, however, no difference between the 3 doses. Therefore this method with these doses is not useful for providing assessment of relative potency.

Chronic anaerobic pneumonitis in a seven-year-old girl

A 7-year-old girl was referred for evaluation of chronic pulmonary disease associated with nasal symptoms of 4 years duration for which she had received frequent courses of antibiotics. Serial chest roentgenograms over a period of 2 years revealed a nonhomogeneous opacity in the right lower lung zone for which she had received 18 months of antituberculous therapy without relief. Evaluation of the patient led to the diagnosis of chronic anaerobic pneumonitis, a rare clinical entity in children. In addition, the patient also had bronchial asthma and chronic rhinitis. Therapy with oral phenoxymethylpenicillin and metronidazole for 6 weeks along with appropriate antiasthma medications abolished her symptoms and resulted in roentgenologic clearance.

Sleep disturbances in clinically stable young asthmatic adults

BACKGROUND

Although nocturnal asthma is a well documented clinical problem, the effect of asthma on sleep itself and morbidity caused thereby have not received adequate attention. It is now recognized that partial sleep deprivation has a considerable effect on human functions.

OBJECTIVES

With this in view, we conducted a study to determine the occurrence and nature of sleep disturbances in a homogeneous group of patients with clinically stable bronchial asthma in their home environment.

METHODS

Thirty young adult unmarried university students with clinically stable bronchial asthma attending the Institute's outpatient department were asked to respond to an asthma/sleep questionnaire and were requested to maintain a sleep diary for 1 week. A similar group of 30 unmarried healthy young university students also underwent an identical workup and functioned as controls. Ten subjects from each group maintained a peak expiratory flow rate (PEFR) diary.

RESULTS

The questionnaire revealed that 28 (93%) of the 30 patients experienced sleep disturbances (average 2.7/subject) as compared to 10 (33%) subjects in the control group (average 0.4/subject). The sleep diary confirmed that 27 (90%) of the 30 patients had sleep disturbances (2.4/subject/wk) as compared with 8 (27%) subjects (0.3/subject/wk) in the control group. These differences were statistically significant. Daytime sleepiness and tiredness (63%) and difficulty in maintaining sleep (60%) along with early morning awakening (46%) were more frequently seen. The asthmatic patients also had a shorter duration of sleep (427 min) as compared with the controls (474 min). These findings were significantly different from the control group.

CONCLUSIONS

Increased daytime sleepiness and tiredness was perhaps a reflection of the poor quality of sleep experienced by patients with clinically stable asthma. This consequently may lead to impaired daytime performance which can have a potentially serious effect for the patient and society.

Inhibitory effects of an anti-IgE antibody E25 on allergen-induced early asthmatic response

Inhaled allergens, acting through IgE-dependent mechanisms, are important triggers of asthma symptoms and inducers of airway hyperresponsiveness and airway inflammation. The effect of anti-IgE recombinant humanized monoclonal antibody-E25 (rhuMAb-E25) on the provocation concentration of allergen causing a 15% fall in FEV1 (allergen PC15) during the allergen-induced early asthmatic response (EAR) was assessed in a multicenter, randomized, double-blind, parallel group study. Ten of 11 allergic asthmatic subjects randomized to receive intravenous rhuMAb-E25, 2 mg/kg on study day 0 and 1 mg/kg on Days 7, 14, 28, 42, 56, and 70 completed the study; nine received intravenous placebo. The allergen PC15 was measured on Days -1, 27, 55, and 77 and methacholine PC20 on Days -2, 42, and 76. rhuMAb-25 was well tolerated and only one patient (active group) was withdrawn because of a generalized urticarial rash after the first dose. Compared with baseline values (Day -1), the median allergen PC15 on Days 27, 55, and 77 were increased by 2.3, 2.2, and 2.7 doubling doses (delta log PC15/0.3) respectively with rhuMAb-E25 and -0.3, +0.1, and -0.8 doubling doses with placebo (p < or = 0.002). Methacholine PC20 improved slightly after rhuMAb-E25, this change becoming statistically significant on Day 76 (p < 0.05); no change was observed in the placebo group. Mean serum-free IgE fell by 89% after rhuMAb-E25 while there was no significant change after placebo. The inhibitory effects of rhuMAb-E25 on allergen-induced EAR suggest that it may be an effective, novel antiallergic treatment for asthma.

Allergic bronchopulmonary aspergillosis: the spectrum of computed tomography appearances

Although computed tomography (CT) of the thorax has been compared to plain chest radiography and bronchography for demonstration of central bronchiectasis (CB) in allergic bronchopulmonary aspergillosis (ABPA), the CT presentation of the disease is yet to be highlighted. With this in view, the CT appearances in 23 patients with ABPA were evaluated. The scans were assessed for bronchial, parenchymal and pleural abnormalities. Central bronchiectasis was identified in all patients, involving 114 (85%) of the 134 lobes and 210 (52%) of the 406 segments studied. Other bronchial abnormalities such as dilated and totally occluded bronchi (11 patients), air-fluid levels within dilated bronchi (five patients), bronchial wall thickening (10 patients) and parallel-line shadows (seven patients) were also observed. Parenchymal abnormalities, which had a predilection for upper lobes, included consolidation in 10 (43%) patients, collapse in four (17%) patients and parenchymal scarring in 19 (83%) patients. A total of six cavities were seen in three (13%) patients, and an emphysematous bullae was detected in one (4%) patient. The pleura was involved in 10 (43%) patients. Ipsilateral pleural effusion with collapse was observed in one patient, while in nine other patients, parenchymal, lesions extended up to the pleura. Concomitant allergic Aspergillus sinusitis (AAS) was also detected in three (13%) of the 23 patients. Computed tomography of the thorax in patients with ABPA provides a sensitive method for the assessment of bronchial, parenchymal and pleural abnormalities, and should constitute a part of the diagnostic work of the disease.

Allergic bronchopulmonary aspergillosis with aspergilloma mimicking fibrocavitary pulmonary tuberculosis

A 47-year-old male, who presented with chronic fibrocavitary pulmonary disease, had received three courses of antituberculous therapy over a period of 17 years without relief. Four years prior to referred he had developed hemoptysis and rhinitis. Evaluation of the patient led to the diagnosis of allergic bronchopulmonary aspergillosis with coexistent aspergilloma, a rather uncommon association. Both his pulmonary and nasal symptoms showed a remarkable response to treatment with oral prednisolone. However, the possibility of concomitant allergic Aspergillus sinusitis remained open as the patient refused to undergo any invasive procedure.

Inhaled corticosteroids do not prevent the development of tolerance to the bronchoprotective effect of salmeterol

INTRODUCTION

Twice-daily inhaled salmeterol produces rapid reduction in its acute bronchoprotective effect against methacholine in patients with mild asthma. This investigation examined this effect in patients with moderate asthma who were using inhaled corticosteroids.

SUBJECTS AND METHODS

Eight asthmatic volunteers who required inhaled corticosteroids for control of their symptoms and who were able to withhold treatment with beta 2-agonists for 4 weeks before and during the study participated in a double-blind, crossover, placebo-controlled study with two random-order treatment periods: inhaled salmeterol, 50 microg twice a day for seven doses, and placebo in similar fashion, with a 7-day or greater washout between these periods. Methacholine inhalation tests were done 1 h after doses 1, 3, 5, and 7, and then 24 h after the last dose of the study inhaler, 10 min post-200 microg salbutamol.

RESULTS

Baseline FEV1 measurements before doses 3, 5, and 7 of salmeterol, ie, 12 h after salmeterol, were significantly higher than all other baseline values. Twenty-four hours after the last dose of salmeterol, the FEV1 was no different from that during the placebo period. The geometric mean methacholine concentration causing a 20% fall in FEV1 (PC20) following the third dose of salmeterol (6.8 mg/mL) was significantly lower than after the first dose of salmeterol (12.0 mg/mL; p=0.031), and this reduction of bronchoprotection persisted following doses 5 and 7. The methacholine PC20 10 min postsalbutamol measured after the salmeterol period was significantly lower than after placebo (5.6 vs 13.3 mg/mL; p<0.001).

CONCLUSIONS

Tolerance to the acute bronchoprotective effect of salmeterol was significant after the first two doses and persisted after the seventh dose. Tolerance to the acute bronchoprotective effect of salbutamol was also significant after regular use of salmeterol for seven doses. These effects, in subjects using inhaled corticosteroids regularly, were similar to the those previously seen in patients with mild asthma using as-required beta 2-agonists only, indicating that tolerance is not prevented by use of inhaled corticosteroids.

Salbutamol-induced increased airway responsiveness to allergen and reduced protection versus methacholine: dose response

BACKGROUND

Two adverse effects of inhaled beta 2-agonists are increased airway responsiveness to allergen and tolerance to the bronchoprotective effect of beta 2-agonists versus bronchoconstrictors (e.g., methacholine).

OBJECTIVE

We studied three doses of inhaled salbutamol, 200, 400, and 800 micrograms/day, to determine dose-response curves for these two adverse effects.

METHODS

Ten atopic patients with mild, stable asthma free of all asthma medications, allergen exposure, and respiratory tract infection for at least 4 weeks participated in a double-blind, random-order, crossover study. There were four 1-week treatment periods with a 1-week washout period: placebo, salbutamol 200 micrograms, 400 micrograms and 800 micrograms per day. After each treatment, we assessed FEV1, bronchodilation 10 minutes after administration of 200 micrograms of salbutamol, methacholine PC20, methacholine dose-shift after administration of 200 micrograms of salbutamol, and allergen PC20.

RESULTS

There was no significant difference in baseline FEV1, bronchodilation, or methacholine PC20. The methacholine dose shift was maximum after the placebo (3.4 +/- 0.22 doubling doses) and was significantly greater (p < 0.01) than all salbutamol regimens (2.2 to 2.6), which were not significantly different from each other (p > 0.05). Allergen PC20 was significantly lower (p < 0.02) after salbutamol 800 micrograms/day (geometric mean = 288 protein nitrogen units [PNU]/ml) than each of the other treatments (447 to 550 PNU/ml), which were not significantly different from each other (p > 0.05).

CONCLUSION

Significant increase in airway responsiveness to allergen occurred only with the largest dose of inhaled salbutamol (800 micrograms/d); however, tolerance to the acute bronchoprotective effect of salbutamol was observed with all the three salbutamol regimens, even 200 micrograms/day. This suggests different mechanisms may be operative in producing these two effects.

Rapid onset of tolerance to the bronchoprotective effect of salmeterol

INTRODUCTION

Twice-daily inhaled salmeterol for 4 weeks produces marked reduction in its acute bronchoprotective effect against methacholine. This investigation examined the onset of this effect over 5 days, and also assessed cross-tolerance with salbutamol.

SUBJECTS AND METHODS

Ten asthmatic volunteers who were able to withhold beta 2-agonist therapy for 4 weeks before and during the study participated in a double-blind, crossover, placebo-controlled study with two random-order treatment periods: inhaled salmeterol, 50 micrograms twice a day for seven doses, and placebo in similar fashion. Methacholine inhalation tests were done 1 h after doses 1, 3, 5, and 7, and then 24 h after the last dose of the study inhaler 10 minutes after 200 micrograms of salbutamol.

RESULTS

Baseline FEV1 value before doses 3, 5, and 7 of salmeterol (ie, 12 h after salmeterol) was significantly higher than all other (n = 7) values. Twenty-four hours after the last dose of salmeterol, the FEV1 was no different from that during the placebo period. The geometric mean methacholine concentration causing a 20% fall in FEV1 (PC20) after the first dose of salmeterol (6.1 mg/mL) was statistically similar to the value achieved 10 min after salbutamol after the placebo period (8.3 mg/mL), and these were significantly (analysis of variance, p < 0.00005) larger than the second, third, and fourth salmeterol days (3.4 mg/mL, 2.6 mg/mL, 1.9 mg/mL, respectively). The methacholine PC20 10 min after salbutamol measured after the salmeterol period was significantly lower than after placebo (2.3 mg/mL vs 8.3 mg/mL; p < 0.001).

CONCLUSIONS

Tolerance to the acute bronchoprotective effect of salmeterol was significant after the first two doses and progressively increased to the seventh dose. Tolerance to the acute bronchoprotective effect of salbutamol was significant after regular use of salmeterol for seven doses.

Interaction of inhaled beta 2 agonist and inhaled corticosteroid on airway responsiveness to allergen and methacholine

Regular treatment with salbutamol increases airway responsiveness to allergen but not to methacholine and produces tolerance to the bronchoprotective effect of salbutamol. The current study addresses the effect of inhaled corticosteroid on these aspects of regular beta 2 agonist use. A group of 13 atopic asthmatic subjects free from all asthma medications and remote from allergen exposure were studied. We used a double-blind, random-order, crossover study to compare four 1-wk treatment periods with > or = 1 wk washout: placebo, salbutamol, 200 micrograms four times per day, budesonide, 400 micrograms four times per day, and the combination of salbutamol and budesonide. We measured the methacholine PC20 and the methacholine dose shift produced acutely by 200 micrograms salbutamol after 7 d and the allergen PC15 after 8 d treatment. Blinded medications were withheld for 8 to 10 h before measurements. The methacholine PC20 was not affected by regular salbutamol but increased significantly (p < 0.014) after both budesonide-containing regimens. Neither the dose shift nor its significant reduction by regularly used beta 2 agonist were influenced by the inhaled corticosteroid. The four allergen PC15 values were significantly different from each other. Compared with placebo, the allergen PC15 was 0.6 doubling doses lower after salbutamol (p = 0.021) and 1.3 doubling doses higher after budesonide (p < 0.001); the allergen PC15 was reduced by 0.53 doubling doses from this new baseline (p = 0.039) when salbutamol and budesonide were used together.(ABSTRACT TRUNCATED AT 250 WORDS)

Preschool health fairs

In Vancouver, as in most metropolitan areas, families with preschoolers (infants to five-year-olds) are diverse in language, culture, ethnicity, class and socio-economic status. Immigration, transiency, very young families, single-parent families, poverty and rapid land development are characteristic in some areas. Despite this diversity, the community health nurses of the Vancouver health department have a mandate to provide early intervention and health promotion services for the preschoolers of this population. This has proved to be quite a challenge.

Regular use of inhaled albuterol and the allergen-induced late asthmatic response

BACKGROUND

We have recently demonstrated that a 2-week course of inhaled albuterol 200 micrograms four times daily caused a near doubling of the allergen-induced early asthmatic response. We hypothesized that this might extend to the more clinically relevant late asthmatic response.

METHODS

We studied 11 patients with atopic asthma who were free from all medications including inhaled beta 2-agonists for more than 4 weeks. We performed a double-blind, random-order, crossover study, comparing the effect of 1-week treatment periods of albuterol 200 micrograms four times daily and placebo 2 puffs four times daily on the early and late asthmatic responses to the same dose of allergen.

RESULTS

Regular use of albuterol did not influence the baseline forced expiratory volume in 1 second (FEV1) (3.40 vs 3.42 L, p = 0.84) or the baseline methacholine provocative concentration causing a 20% fall in FEV1 (PC20) (geometric mean, 2.4 mg/ml vs 1.9 mg/ml, p = 0.38). However, all aspects of the allergen-induced asthmatic response were increased. After the 1-week albuterol treatment, the early asthmatic response was slightly greater (21.1% vs 17.9% FEV1 fall, p = 0.26), the late response was greater (23.1% vs 13.2% FEV1 fall, p = 0.0027), and the allergen-induced increase in airway responsiveness (change in log methacholine PC20) was greater (0.37 vs 0.20, p = 0.045).

CONCLUSIONS

One week of albuterol treatment (200 micrograms four times daily) increased the late asthmatic response and allergen-induced increase in airway responsiveness. This suggests that the combination of regular use of inhaled beta 2-agonist and allergen exposure may cause more airway inflammation than allergen exposure alone.