Fatal hemorrhagic bronchopneumonia caused by Bordetella bronchiseptica in an immunocompetent patient.

Introduction: Bordetella bronchiseptica is a rare cause of hemorrhagic bronchopneumonia. Important to the clinician is a clear understanding that the treatment of this rare organism differs greatly from the successful antibiotic treatment of the more common Bordetella species, pertussis and parapertussis. Case report: A 64-year-old female presented to the emergency department after experiencing one week of worsening hemoptysis. Upon admission, she was afebrile and all initial laboratory test results were normal. Bronchoalveolar hemorrhage suggested by radiographic imaging was confirmed by bronchoscopy. Bronchoalveolar lavage (BAL) cultures contained unspeciated Bordetella. Rapid worsening of the hemoptysis led to intubation and the decision to perform bronchial artery embolization. However, the intensity of the hemoptysis persisted. Septic shock ensued despite treatment with broad spectrum antibiotics including azithromycin, vancomycin, and cefepime. The microbiological speciation results finalized shortly after the patient's death. The identified organism was B. bronchiseptica. Conclusions: Although macrolide antibiotics are first line treatment for B. pertussis and parapertussis, macrolide antibiotics are generally not effective against B. bronchiseptica. Clinical suspicion of B. bronchiseptica infection should prompt consideration of alternative antibiotics known to be effective against this rare species, including carbapenems and fluoroquinolones. The use of these latter antibiotics may advisably be considered as an empirical treatment during the delay of microbiological speciation.

Promoting High-Oxidation-State Metal Active Sites in a Hollow Ternary Metal Fluoride Nanoflake Array for Urea Electrolysis.

The adsorption ability of hydrogen, hydroxide, and oxygenic intermediates plays a crucial role in electrochemical water splitting. Electron-deficient metal-active sites can prompt electrocatalytic activity by improving the adsorption ability of intermediates. However, it remains a significant challenge to synthesize highly abundant and stable electron-deficient metal-active site electrocatalysts. Herein, we present a general approach to synthesizing a hollow ternary metal fluoride (FeCoNiF2) nanoflake array as an efficient and robust bifunctional electrocatalyst for the hydrogen evolution reaction (HER) and urea oxidation reaction (UOR). We find that the F anion withdraws electrons from the metal centers, inducing an electron-deficient metal center catalyst. The rationally designed hollow nanoflake array exhibits the overpotential of 30 mV for HER and 130 mV for UOR at a current density of 10 mA cm-2 and superior stability without decay events over 150 h at a large current density of up to 100 mA cm-2. Remarkably, the assembled urea electrolyzer using a bifunctional hollow FeCoNiF2 nanoflake array catalyst requires cell voltages of only 1.352 and 1.703 V to afford current densities of 10 and 100 mA cm-2, respectively, which are 116 mV less compared with that required for overall water splitting.

Insight into the direct conversion of methane to methanol on modified ZIF-204 from the perspective of DFT-based calculations.

Direct oxidation of methane over oxo-doped ZIF-204, a bio-mimetic metal-organic framework, is investigated under first-principles calculations based on density functional theory. In the pristine ZIF-204, the tetrahedral methane molecule anchors to an open monocopper site via the so-called η2 configuration with a physisorption energy of 0.24 eV. This weak binding arises from an electrostatic interaction between the negative charge of carbon in the methane molecule and the positive Cu2+ cation in the framework. In the modified ZIF-204, the doped oxo species is stabilized at the axial position of a CuN4-base square pyramid at a distance of 2.06 Å. The dative covalent bond between Cu and oxo is responsible for the formation energy of 1.06 eV. With the presence of the oxo group, the presenting of electrons in the O_pz orbital accounts for the adsorption of methane via hydrogen bonding with an adsorption energy of 0.30 eV. The methane oxidation can occur via either a concerted direct oxo insertion mechanism or a hydrogen-atom abstraction radical rebound mechanism. Calculations on transition-state barriers show that reactions via the concerted direct oxo insertion mechanism can happen without energy barriers. Concerning the hydrogen-atom abstraction radical rebound mechanism, the C-H bond dissociation of the CH4 molecule is barrierless, but the C-O bond recombination to form the CH3OH molecule occurs through a low barrier of 0.16 eV. These predictions suggest the modified ZIF-204 is a promising catalyst for methane oxidization.

Impacts of COVID-19 crisis and some related factors on the mental health of 37150 Vietnamese students: a cross-sectional online study.

BACKGROUND: University students are vulnerable to changes due to COVID-19 pandemic. Although warning has been made about the impact of this crisis on students' mental health, there are barely any sufficient study. This work investigated how the pandemic affected the mental health of students at the Vietnam National University of Ho Chi Minh City (VNU-HCMC) and efficiency of available mental health supportive methods. METHODS: An online survey was conducted among students at Vietnam National University of Ho Chi Minh City (VNU-HCMC) from October 18, 2021, to October 25, 2021. Microsoft Excel 16.51 (Microsoft, USA) and R language, Epi packages 2.44 and 4.1.1 (rdrr.io) were used for data analysis. RESULTS: Thirty-seven thousand one hundred fifty students participated in the survey, including 48.4% female and 51.6% male. Online learning pressure was mainly recorded (65.1%). Many students suffered from sleeping disorders (56.2%). Some reported being victims of abuse (5.9%). Female students expressed a significantly higher level of distress than males, particularly the feeling of ambiguity about the purpose of life (p-value < 0.0001, OR: 0.94, 95% CI: [0.95-0.98]). Third-year students suffered higher stress levels than others, especially in online learning (68.8%, p-value < 0.05). Mental health statuses among students of different lockdown status regions were not significantly different. Therefore, lockdown status did not affect the stress levels of students which suggested that poor mental health outcomes seemed to root in the suspension of everyday university life rather than the prohibition of going out. CONCLUSIONS: During COVID-19, students experienced lots of stress and mental problems. These findings underscore the importance of academic and innovative activities, bringing attention to the needs of interactive study and extra-curricular activities.

Human social conditions predict the risk of exposure to zoonotic parasites in companion animals in East and Southeast Asia.

BACKGROUND: A recent dramatic surge in pet ownership has been observed across metropolitan areas in Asia. To date, there is a dearth of information on the risk associated with pet ownership for the transmission of parasites on a large scale in Asia, despite this continent giving rise to the largest burden of zoonotic infections worldwide. METHODS: We explored the nature and extent of zoonotic internal (endo-) and external (ecto-) parasites and arthropod-borne pathogens in 2381 client-owned dogs and cats living in metropolitan areas of eight countries in East and Southeast Asia using reliable diagnostic tests and then undertook extensive statistical analyses to define predictors of exposure to zoonotic pathogens. RESULTS: The estimated ORs for overall parasite infections are 1.35 [95% CIs 1.07;1.71] in young animals and 4.10 [1.50;11.2] in the animal group older than 15 years as compared with adult animals, 0.61 [0.48;0.77] in neutered animals as compared to unneutered animals, 0.36 [0.26;0.50] in animals living in urban areas as compared with rural areas, 1.14 [1.08;1.21] for each 1 °C increase of annual mean temperature which varies from 12.0 to 28.0 °C, and 0.86 [0.78;0.95] for each year of life expectancy which varies from 70.9 to 83.3 years. CONCLUSIONS: Here we highlight the influence of human life expectancy and the neutering status of the animals, which reflect increased living standards through access to education and human and veterinary health care, to be both strongly associated with exposure to zoonotic parasites. An integrated approach of local and international authorities to implement and manage educational programs will be crucial for the control of zoonotic infections of companion animals in Asia.

Parasites live on or inside animals or humans and can cause disease. Companion animals (pets) with parasites present a potential risk to the health of their owners, as certain kinds of parasites (known as zoonotic parasites) can affect both animal and human health. Here, we investigated whether human social conditions are associated with zoonotic parasite infections in companion animals in East and Southeast Asia. We found that higher human life expectancy and neutering of the companion animals were associated with fewer zoonotic parasite infections in the animals. These findings highlight the need for an enhanced commitment of local authorities to establish prevention campaigns, including education programs, against zoonotic pathogens. These measures will play a crucial role in alleviating the impact of these diseases in companion animals and humans in Asia.

Coupling Amorphous Ni Hydroxide Nanoparticles with Single-Atom Rh on Cu Nanowire Arrays for Highly Efficient Alkaline Seawater Electrolysis.

Exploring efficient catalysts for alkaline seawater electrolysis is highly desired yet challenging. Herein, coupling single-atom rhodium with amorphous nickel hydroxide nanoparticles on copper nanowire arrays is designed as a new active catalyst for the highly efficient alkaline seawater electrolysis. We found that an amorphous Ni(OH)2 nanoparticle is an effective catalyst to accelerate the water dissociation step. In contrast, the single-atom rhodium is an active site for adsorbed hydrogen recombination to generate H2. The NiRh-Cu NA/CF catalyst shows superior electrocatalytic activity toward HER, surpassing a benchmark Pt@C. In detail, the NiRh-Cu NA/CF catalyst exhibits HER overpotentials as low as 12 and 21 mV with a current density of 10 mA cm-2 in fresh water and seawater, respectively. At high current density, the NiRh-Cu NA/CF catalyst also exhibits an outstanding performance, where 300 mA cm-2 can be obtained at an overpotential of 155 mV and shows a slight fluctuation in the current density over 30 h.

A decomposition mechanism for Mn2(DSBDC) metal-organic frameworks in the presence of water molecules.

In this work, we investigate the effects of water on the structural stability of Mn2(DSBDC) metal-organic framework (MOF) using DFT-based calculations. It has been found that the adsorption of multiple water molecules forming a hydrogen bond network around the Mn centers plays an important role in the decomposition process. Different effects contribute to the destabilization of the MOF: water molecules that directly coordinate to the open sites displayed by a part of the Mn centers can induce a significant shift in the charge distribution as indicated by the analysis of charge density differences and the Bader charges. This adsorption process leads to a slight elongation of the metal-linker bonds. The direct interaction with the Mn center is the most stable adsorption mode for water in Mn2(DSBDC). Once these adsorption sites at the Mn centers are fully occupied, additional water molecules start to bind via hydrogen bonds to the already present water molecules or, more importantly, to the linker molecules. This, in return, leads to a significant weakening of the Mn-linker bonds, thus allowing water insertion into the Mn-linker bonds with a barrier of only 0.16 eV, which is believed to initiate the decomposition of the Mn2(DSBDC) framework. Based on a kinetic Monte Carlo model, it can be shown that high temperatures can prevent the adsorption of water molecules around the Mn sites and thus slow down the MOF decomposition.

Molecular detection of pathogens in ticks and fleas collected from companion dogs and cats in East and Southeast Asia.

BACKGROUND: Ticks and fleas are considered amongst the most important arthropod vectors of medical and veterinary concern due to their ability to transmit pathogens to a range of animal species including dogs, cats and humans. By sharing a common environment with humans, companion animal-associated parasitic arthropods may potentially transmit zoonotic vector-borne pathogens (VBPs). This study aimed to molecularly detect pathogens from ticks and fleas from companion dogs and cats in East and Southeast Asia. METHODS: A total of 392 ticks and 248 fleas were collected from 401 infested animals (i.e. 271 dogs and 130 cats) from China, Taiwan, Indonesia, Malaysia, Singapore, Thailand, the Philippines and Vietnam, and molecularly screened for the presence of pathogens. Ticks were tested for Rickettsia spp., Anaplasma spp., Ehrlichia spp., Babesia spp. and Hepatozoon spp. while fleas were screened for the presence of Rickettsia spp. and Bartonella spp. RESULT: Of the 392 ticks tested, 37 (9.4%) scored positive for at least one pathogen with Hepatozoon canis being the most prevalent (5.4%), followed by Ehrlichia canis (1.8%), Babesia vogeli (1%), Anaplasma platys (0.8%) and Rickettsia spp. (1%) [including Rickettsia sp. (0.5%), Rickettsia asembonensis (0.3%) and Rickettsia felis (0.3%)]. Out of 248 fleas tested, 106 (42.7%) were harboring at least one pathogen with R. felis being the most common (19.4%), followed by Bartonella spp. (16.5%), Rickettsia asembonensis (10.9%) and "Candidatus Rickettsia senegalensis" (0.4%). Furthermore, 35 Rhipicephalus sanguineus ticks were subjected to phylogenetic analysis, of which 34 ticks belonged to the tropical and only one belonged to the temperate lineage (Rh. sanguineus (sensu stricto)). CONCLUSION: Our data reveals the circulation of different VBPs in ticks and fleas of dogs and cats from Asia, including zoonotic agents, which may represent a potential risk to animal and human health.

Zoonotic Vectorborne Pathogens and Ectoparasites of Dogs and Cats in Eastern and Southeast Asia.

To provide data that can be used to inform treatment and prevention strategies for zoonotic pathogens in animal and human populations, we assessed the occurrence of zoonotic pathogens and their vectors on 2,381 client-owned dogs and cats living in metropolitan areas of 8 countries in eastern and Southeast Asia during 2017-2018. Overall exposure to ectoparasites was 42.4% in dogs and 31.3% in cats. Our data cover a wide geographic distribution of several pathogens, including Leishmania infantum and zoonotic species of filariae, and of animals infested with arthropods known to be vectors of zoonotic pathogens. Because dogs and cats share a common environment with humans, they are likely to be key reservoirs of pathogens that infect persons in the same environment. These results will help epidemiologists and policy makers provide tailored recommendations for future surveillance and prevention strategies.

From the perspectives of DFT calculations, thermodynamic modeling, and kinetic Monte Carlo simulations: the interaction between hydrogen and Sc2C monolayers.

In this study, we have examined the adsorption properties of hydrogen on pristine Sc2C monolayers by DFT calculations. Based on these calculations, we have proposed a thermodynamic model to estimate the hydrogen storage capability within the typical ranges for the operating temperature and pressure. Our thermodynamic modeling has shown that the maximum uptake of usable hydrogen could reach up to 7.2 wt% under cryogenic conditions. When calculating the usable hydrogen uptake, we have taken into consideration that, under realistic operating conditions, not all hydrogen adsorbed on pristine Sc2C can be desorbed from the surface, as some surface-adsorbate interactions are too strong. On the other hand, the interaction between the usable hydrogen and Sc2C appears to be too weak to reach the targets for the year 2025 set by the US Department of Energy (5.5 wt% at operating temperatures between 233 K and 358 K and delivery pressures of up to 12 bar). According to the modeling results, one needs to decrease the temperature to 120 K to reach 5.5 wt% hydrogen uptake at 12 bar. The results obtained with the thermodynamic model have been confirmed with a kinetic Monte Carlo simulation, which has also been used to estimate the time scale of the hydrogen adsorption and desorption processes. In addition, we have also evaluated the changes in the electronic structure of the Sc2C monolayer upon adsorbing hydrogen. As the band gap of Sc2C changes significantly upon adsorbing H2, Sc2C may have more potential as a hydrogen detector instead of as a hydrogen storage material.

Hydrogen adsorption mechanism of MOF-74 metal-organic frameworks: an insight from first principles calculations.

The microscopic mechanism of the H2 adsorption of two Mg-MOF-74 isoreticular frameworks, one with a benzenedicarboxylate (BDC) linker and the other with a dihydroxyfumarate (DHF) linker, were studied on the basis of density functional theory (DFT) method. Possible adsorption sites on the internal surface of the two MOFs were detected using ab initio molecular dynamics (AIMD) annealing simulations. The simulations were able to reproduce all adsorption sites which have been experimentally observed for the BDC-based M-MOF-74 frameworks with M = Ni and Zn. In descending order of binding strengths, they are the adsorption sites primarily induced by the open metal sites P1, the oxygen atoms of the oxido groups P2 and the aromatic rings P3. The H2-framework binding strengths were properly evaluated by taking into account the vibrational zero-point energy (ZPE) contribution. An additional type of adsorption sites induced by the oxygen atoms of the carboxyl groups P4 is predicted for the Mg-MOF-74 framework. Two types of adsorption sites primarily induced by the open metal sites P1 and oxygen atoms of the carboxyl groups P2 were predicted for the DHF-based Mg-MOF-74 framework. Detailed analysis of the electron density showed that the electrostatic interaction of the H2 molecule with the charge distribution of the local framework environment within a radius of ∼3.5 Šis a key factor to define adsorption positions and binding strength. The absence of the P4 sites in the BDC-based Zn-MOF-74 framework is caused by the lower charge density at the oxygen atoms induced by less electro-positive metal. The substitution of the nonaromatic DHF linker for the aromatic BDC linker reduces the binding strength at the metal induced adsorption sites by 1.45 kJ mol-1 due to the absence of the aromatic ring.

Discovery of tandem and interspersed segmental duplications using high-throughput sequencing.

MOTIVATION: Several algorithms have been developed that use high-throughput sequencing technology to characterize structural variations (SVs). Most of the existing approaches focus on detecting relatively simple types of SVs such as insertions, deletions and short inversions. In fact, complex SVs are of crucial importance and several have been associated with genomic disorders. To better understand the contribution of complex SVs to human disease, we need new algorithms to accurately discover and genotype such variants. Additionally, due to similar sequencing signatures, inverted duplications or gene conversion events that include inverted segmental duplications are often characterized as simple inversions, likewise, duplications and gene conversions in direct orientation may be called as simple deletions. Therefore, there is still a need for accurate algorithms to fully characterize complex SVs and thus improve calling accuracy of more simple variants. RESULTS: We developed novel algorithms to accurately characterize tandem, direct and inverted interspersed segmental duplications using short read whole genome sequencing datasets. We integrated these methods to our TARDIS tool, which is now capable of detecting various types of SVs using multiple sequence signatures such as read pair, read depth and split read. We evaluated the prediction performance of our algorithms through several experiments using both simulated and real datasets. In the simulation experiments, using a 30× coverage TARDIS achieved 96% sensitivity with only 4% false discovery rate. For experiments that involve real data, we used two haploid genomes (CHM1 and CHM13) and one human genome (NA12878) from the Illumina Platinum Genomes set. Comparison of our results with orthogonal PacBio call sets from the same genomes revealed higher accuracy for TARDIS than state-of-the-art methods. Furthermore, we showed a surprisingly low false discovery rate of our approach for discovery of tandem, direct and inverted interspersed segmental duplications prediction on CHM1 (<5% for the top 50 predictions). AVAILABILITY AND IMPLEMENTATION: TARDIS source code is available at https://github.com/BilkentCompGen/tardis, and a corresponding Docker image is available at https://hub.docker.com/r/alkanlab/tardis/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Analysis of peptide-SLA binding by establishing immortalized porcine alveolar macrophage cells with different SLA class II haplotypes.

Primary porcine alveolar macrophages (PAM) are useful for studying viral infections and immune response in pigs; however, long-term use of these cells is limited by the cells' short lifespan. We immortalized primary PAMs by transfecting them with both hTERT and SV40LT and established two immortalized cell lines (iPAMs) actively proliferating even after 35 passages. These cells possessed the characteristics of primary PAMs, including strong expression of swine leukocyte antigen (SLA) class II genes and the inability to grow anchorage-independently. We characterized their SLA genes and subsequently performed peptide-SLA binding assays using a peptide from porcine circovirus type 2 open reading frame 2 to experimentally measure the binding affinity of the peptide to SLA class II. The number of peptides bound to cells measured by fluorescence was very low for PK15 cells (7.0% ± 1.5), which are not antigen-presenting cells, unlike iPAM61 (33.7% ± 3.4; SLA-DQA*0201/0303, DQB1*0201/0901, DRB1*0201/1301) and iPAM303 (73.3% ± 5.4; SLA DQA*0106/0201, DQB1*0202/0701, DRB1*0402/0602). The difference in peptide binding between the two iPAMs was likely due to the allelic differences between the SLA class II molecules that were expressed. The development of an immortal PAM cell panel harboring diverse SLA haplotypes and the use of an established method in this study can become a valuable tool for evaluating the interaction between antigenic peptides and SLA molecules and is important for many applications in veterinary medicine including vaccine development.

ß2-microglobulin gene duplication in cetartiodactyla remains intact only in pigs and possibly confers selective advantage to the species.

Several ß2-microglobulin (B2M) -bound protein complexes undertake key roles in various immune system pathways, including the neonatal Fc receptor (FcRn), cluster of differentiation 1 (CD1) protein, non-classical major histocompatibility complex (MHC), and well-known MHC class I molecules. Therefore, the duplication of B2M may lead to an increase in the biological competence of organisms to the environment. Based on the pig genome assembly SSC10.2, a segmental duplication of ~45.5 kb, encoding the entire B2M protein, was identified in pig chromosome 1. Through experimental validation, we confirmed the functional duplication of the B2M gene with a completely identical coding sequence between two copies in pigs. Considering the importance of B2M in the immune system, we performed the phylogenetic analysis of B2M duplication in ten mammalian species, confirming the presence of B2M duplication in cetartioldactyls, like cattle, sheep, goats, pigs and whales, but non-cetartiodactyl species, like mice, cats, dogs, horses, and humans. The density of long interspersed nuclear element (LINE) at the edges of duplicated blocks (39 to 66%) was found to be 2 to 3-fold higher than the average (20.12%) of the pig genome, suggesting its role in the duplication event. The B2M mRNA expression level in pigs was 12.71 and 7.57 times (2-ΔΔCt values) higher than humans and mice, respectively. However, we were unable to experimentally demonstrate the difference in the level of B2M protein because species specific anti-B2M antibodies are not available. We reported, for the first time, the functional duplication of the B2M gene in animals. The identification of partially remaining duplicated B2M sequences in the genomes of only cetartiodactyls indicates that the event was lineage specific. B2M duplication could be beneficial to the immune system of pigs by increasing the availability of MHC class I light chain protein, B2M, to complex with the proteins encoded by the relatively large number of MHC class I heavy chain genes in pigs. Further studies are necessary to address the biological meaning of increased expression of B2M.

Pulmonary embolism with endovascular thrombolysis for thrombosed hemodialysis arteriovenous access
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AIMS: Acute thrombosis of hemodialysis (HD) arteriovenous access is an urgent problem for HD patients and is commonly managed by endovascular thrombolysis. Pulmonary embolism (PE) is a recognized complication of HD access thrombosis and thrombolysis but the risk and outcomes are unclear. This study aims to determine the incidence, predictors, and outcomes of PE after endovascular thrombolysis of HD arteriovenous access in patients presenting with acute thrombosis. MATERIALS AND METHODS: A single-center retrospective study was performed for all adult chronic kidney disease patients undergoing arteriovenous access thrombolysis between January 1, 2012, and December 31, 2014. Investigation for PE with CT pulmonary angiography or ventilation/perfusion scintigraphy (V/Q scan) was performed as clinically directed by the managing clinicians. In cases diagnosed with PE, the pulmonary embolism severity index (PESI) was calculated. RESULTS: A total of 48 (median age 68) patients underwent 74 thrombolysis procedures. Thrombolysis techniques were divided into pharmacological (44.6%), mechanical (17.6%), or pharmacomechanical (37.8%). Clinical success was achieved in 56/74 (75.7%) of procedures. Five episodes of thrombolysis for access thrombosis (6.8%) were associated with clinically symptomatic PE. The PESI score ranged from 51 to 127. All patients with PE were managed with 3 - 6 months of anticoagulation and recovered clinically. There were no statistically significant differences in baseline characteristics, methods of thrombolysis, or clot burden in patients that developed a PE. CONCLUSION: There is a clinically significant risk of symptomatic PE after arteriovenous access thrombolysis for access thrombosis in HD patients.
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SurfKin: an ab initio kinetic code for modeling surface reactions.

In this article, we describe a C/C++ program called SurfKin (Surface Kinetics) to construct microkinetic mechanisms for modeling gas-surface reactions. Thermodynamic properties of reaction species are estimated based on density functional theory calculations and statistical mechanics. Rate constants for elementary steps (including adsorption, desorption, and chemical reactions on surfaces) are calculated using the classical collision theory and transition state theory. Methane decomposition and water-gas shift reaction on Ni(111) surface were chosen as test cases to validate the code implementations. The good agreement with literature data suggests this is a powerful tool to facilitate the analysis of complex reactions on surfaces, and thus it helps to effectively construct detailed microkinetic mechanisms for such surface reactions. SurfKin also opens a possibility for designing nanoscale model catalysts.

The base-to-base induced-tropia prism test for detection of amblyopia: a pilot study.

PURPOSE: To investigate the accuracy of the base-to-base prism test (BBPT), which entails inducing an esotropia with the use of base-in prisms before each eye, in the diagnosis of amblyopia. METHODS: Participants were consecutive patients recruited from a pediatric ophthalmology practice who were able to perform logMAR acuity testing. All participants underwent an orthoptic examination, including logMAR visual acuity testing, and a sensorimotor evaluation. Patients with an interocular difference of 2 or more lines were considered to have amblyopia. Fixation preference was assessed by use of both the vertical fixation test and the BBPT. The agreement between the BBPT and visual acuity was analyzed and compared with the agreement between the vertical fixation test and visual acuity. RESULTS: Fifty-one consecutive patients aged 4 to 17 (mean, 9.8 years; SD ± 3.4) were included, of whom 11 were diagnosed with amblyopia. Kappa analysis showed moderate but significant agreement between the BBPT and logMAR (κ = 0.453, p = 0.001), whereas the vertical fixation test demonstrated only a fair agreement (κ = 0.254, p = 0.061). The overall sensitivity for the BBPT was 72.7% (95% confidence interval [95% CI], 43.4%-90.3%) but only 40% for the vertical fixation test (95% CI, 16.8%-69.7%). For the BBPT, specificity was 80% (95% CI, 65.2%-89.5%); for the vertical fixation test, 78% (95% CI, 63.3%-88.0%). CONCLUSIONS: The BBPT appears to be more sensitive than the vertical fixation test for detecting amblyopia in our patient population. The 2 tests had similar specificity.

The fixation target influences the near deviation and AC/A ratio in intermittent exotropia.

PURPOSE: Divergence excess intermittent exotropia is thought to comprise 2 types of deviation, simulated and true. It is believed that simulated divergence excess is akin to a basic deviation but is controlled at near through accommodative and adaptive fusional vergences. While fixation target detail is known to influence accommodation and subsequently deviation size, no previous study has investigated the effect of the fixation target on the AC/A ratio in intermittent exotropia and its influence on the deviation's classification. METHOD: Twenty-five participants with intermittent exotropia underwent near and distance measurement before and after 45 minutes of occlusion. The near angle was also measured through +3.00 D lenses, and using 2 different sized targets, an N60-equivalent "butterfly" picture and N5 print. The gradient AC/A ratio was calculated for each target. RESULTS: There was a significant difference between the measurements using the 2 targets, t(24) = 8.3, p < or = <0.001. On average, the near angle was 8.8(Delta) greater using the N5 print. This also resulted in a significant difference for the AC/A ratio, t(24) = -8.4, p < 0.001, the mean with the target being 3.6(Delta):1D, as compared to 6.6(Delta):1D with the N5 print. CONCLUSIONS: Through careful control of accommodation by ensuring relaxation with plus lenses to clear N5 print, we revealed increases in the AC/A ratio and unmasked deviations that would otherwise have been considered to be characteristic of true divergence excess. Simulated and true deviations are possibly part of a continuum and clinical delineation may be influenced by testing artefact.

Intracranial blood flow velocities and CO2 reactivity in diagnosing migraine-related dizziness.

OBJECTIVE: Migraine-related dizziness can present with or without headache, often making diagnosis difficult. Flow velocity and CO 2 reactivity testing using transcranial Doppler (TCD) measurement of intracranial blood flow has been described as abnormal in patients with classic or common migraine. This study sought to determine the utility, if any, of this noninvasive technique in the diagnosis of migraine-related dizziness. STUDY DESIGN AND SETTING: A prospective, controlled study in academic neurotology and neurology practices was conducted. Nine patients with migraine-related dizziness and 10 patients with no history of migraine or dizziness were tested with transcranial Doppler ultrasound in a blinded fashion. RESULTS: No statistically significant differences in intracranial blood flow velocities or in cerebrovascular reactivity to hypocapnia were found between patients and controls. CONCLUSIONS: Assessment of intracranial blood flow velocity and CO 2 reactivity using TCD does not help in the diagnosis of migraine-related dizziness. SIGNIFICANCE: A reliable objective test for the diagnosis of migraine-related dizziness remains elusive, and the diagnosis of this patient group continues to be suboptimal.

Lack of SARS transmission and U.S. SARS case-patient.

In early April 2003, severe acute respiratory syndrome (SARS) was diagnosed in a Pennsylvania resident after his exposure to persons with SARS in Toronto, Canada. To identify contacts of the case-patient and evaluate the risk for SARS transmission, a detailed epidemiologic investigation was performed. On the basis of this investigation, 26 persons (17 healthcare workers, 4 household contacts, and 5 others) were identified as having had close contact with this case-patient before infection-control practices were implemented. Laboratory evaluation of clinical specimens showed no evidence of transmission of SARS-associated coronavirus (SARS-CoV) infection to any close contact of this patient. This investigation documents that, under certain circumstances, SARS-CoV is not readily transmitted to close contacts, despite ample unprotected exposures. Improving the understanding of risk factors for transmission will help focus public health control measures.