To estimate the spatially varying noise map using a redundant series of magnitude MR images.

We exploit redundancy in non-Gaussian distributed multidirectional diffusion MRI data by identifying its noise-only principal components, based on the theory of noisy covariance matrices. The bulk of principal component analysis eigenvalues, arising due to noise, is described by the universal Marchenko-Pastur distribution, parameterized by the noise level. This allows us to estimate noise level in a local neighborhood based on the singular value decomposition of a matrix combining neighborhood voxels and diffusion directions.

We present a model-independent local noise mapping method capable of estimating the noise level down to about 1% error. In contrast to current state-of-the-art techniques, the resultant noise maps do not show artifactual anatomical features that often reflect physiological noise, the presence of sharp edges, or a lack of adequate a priori knowledge of the expected form of MR signal.

Simulations and experiments show that typical diffusion MRI data exhibit sufficient redundancy that enables accurate, precise, and robust estimation of the local noise level by interpreting the principal component analysis eigenspectrum in terms of the Marchenko-Pastur distribution. Magn Reson Med 76:1582-1593, 2016. © 2015 International Society for Magnetic Resonance in Medicine.

Evidence from previous coronavirus outbreaks has shown that infected patients are at risk for developing psychiatric and mental health disorders, such as depression, anxiety, and sleep disturbances. To construct a comprehensive picture of the mental health status in COVID-19 patients, we conducted a systematic review and random-effects meta-analysis to assess the prevalence of depression, anxiety, and sleep disturbances in this population. We searched MEDLINE, EMBASE, PubMed, Web of Science, CINAHL, Wanfang Data, Wangfang Med Online, CNKI, and CQVIP for relevant articles, and we included 31 studies (n = 5153) in our analyses. We found that the pooled prevalence of depression was 45% (95% CI: 37-54%, I² = 96%), the pooled prevalence of anxiety was 47% (95% CI: 37-57%, I² = 97%), and the pooled prevalence of sleeping disturbances was 34% (95% CI: 19-50%, I² = 98%). We did not find any significant differences in the prevalence estimates between different genders; however, the depression and anxiety prevalence estimates varied based on different screening tools. More observational studies assessing the mental wellness of COVID-19 outpatients and COVID-19 patients from countries other than China are needed to further examine the psychological implications of COVID-19 infections.

Keywords: anxiety; coronavirus; depression; meta-analysis; pandemic; sleep disturbance.

BACKGROUND

In patients with venous thromboembolism (VTE), identifying clinical risk factors for recurrence during the initial 3 months of anticoagulant therapy and knowledge of the time course of recurrence may help clinicians decide about the frequency of clinical surveillance and the appropriateness of outpatient treatment.

METHODS

Analysis of a randomized controlled trial database involving 1021 patients with VTE (750 with deep vein thrombosis [DVT] and 271 with pulmonary embolism [PE]) who were followed up for 3 months after the start of anticoagulant therapy. All patients received initial treatment with unfractionated heparin or a low-molecular-weight heparin (reviparin) and a coumarin derivative starting the first or second day of treatment, with a target international normalized ratio of 2.0 to 3.0.

RESULTS

Four independent clinical risk factors for recurrent VTE were identified: (1) cancer (odds ratio [OR], 2.72; 95% confidence interval [CI], 1. 39-5.32), (2) chronic cardiovascular disease (OR, 2.27; 95% CI, 1. 08-4.97), (3) chronic respiratory disease (OR, 1.91; 95% CI, 0.85-4. 26), and (4) other clinically significant medical disease (OR, 1.79; 95% CI, 1.00-3.21). Older age was associated with a decreased risk for recurrent VTE (OR, 0.76; 95% CI, 0.64-0.92). Previous VTE, sex, and idiopathic VTE were not risk factors for recurrence. In patients with DVT or PE, there was no significant difference in the rates of recurrent nonfatal VTE (4.8% vs 4.1%; P =.62), major bleeding (2.9% vs 2.2%; P =.53), and non-VTE death (6.4% vs 7.8%; P =.45), but recurrent fatal PE was more frequent in patients with PE than DVT (2. 2% vs 0%; P<.01). There was a clustering of recurrent VTE episodes during the initial 2 to 3 weeks after the start of treatment.

CONCLUSIONS

During the initial 3 months of anticoagulant therapy, recurrent VTE is more likely to occur in patients with cancer, chronic cardiovascular disease, chronic respiratory disease, or other clinically significant medical disease. Patients with PE are as likely to develop recurrent VTE as those with DVT; however, recurrence is more likely to be fatal in patients who initially present with PE. Arch Intern Med. 2000;160:3431-3436.

The temporary improvement of visuospatial neglect during galvanic vestibular stimulation (Scand. J. Rehabil. Med. 31 (1999)117) may result from correction of the spatial reference frame distorted by the responsible lesion. Prior to an investigation of the neural basis of this effect in neurological patients, exploration of the neural mechanisms underlying such procedures in normals is required to provide insight into the physiological basis thereof. Despite their clinical impact, the neural mechanisms underlying the interaction of galvanic (and other) vestibular manipulations with visuospatial processing (and indeed the neural bases of how spatial reference frames are computed in man) remain to be clarified. We accordingly used fMRI in normal volunteers to investigate the effect of galvanically induced interference with the egocentric spatial reference frame on the neural processes underlying allocentric visuospatial (line bisection) judgments. A significant specific interaction of galvanic vestibular stimulation with the neural mechanisms underlying allocentric visuospatial judgments was observed in right posterior parietal and ventral premotor cortex only. Activation of these areas previously found to be damaged in visuospatial neglect suggests that these effects reflect the increased processing demands when compensating for the distorted egocentric spatial reference frame while maintaining accurate performance during the allocentric spatial task. These results thus implicate right posterior parietal and right ventral premotor cortex in the computation of spatial reference frames. Furthermore, our data imply a specific physiological basis for the temporary improvement of visuospatial neglect in patients with right hemisphere lesions during galvanic vestibular stimulation and may thus impact upon the rehabilitation of neglect: understanding the interaction of galvanic vestibular stimulation with allocentric visuospatial judgments in healthy volunteers may lead to the more effective deployment of such techniques in neurological patients.

Analysis of a transgene-induced mutation at the mouse med locus led to the identification of the novel voltage-gated sodium channel gene Scn8a (Burgess, D. L., Kohrman, D. C., Galt, J., Plummer, N. W., Jones, J. M., Spear, B., and Meisler, M. H.(1995) Nat. Genet. 10, 461-465). We now report the identification of splicing defects in two spontaneous mutations of Scn8a. The original med mutation was caused by insertion of a truncated LINE element into exon 2 of Scn8a. The med transcript is spliced from exon 1 to a cryptic acceptor site in intron 2. A 4-base pair deletion within the 5' donor site of exon 3 in the medJ allele results in splicing from exon 1 to exon 4. Both mutant transcripts have altered reading frames with premature stop codons close to the N terminus of the protein. Loss of Scn8a expression results in progressive paralysis and early death. Intron 2 of Scn8a is flanked by minor class AT-AC splice sites. The observed splicing patterns of the med and medJ mutant transcripts provide the first evidence for preferential in vivo splicing between donor and acceptor sites of the same class. The apparent functional incompatibility may be a consequence of the different composition of spliceosomes bound to major and minor splice sites.

Techniques and approaches from population and community ecology, along with theoretical viewpoints from criminology and the 'social support hypothesis' of health maintenance, are used to examine recent patterns of rising homicide and suicide, intensified substance abuse, low birth weight and AIDS deaths in the Bronx section of New York City. Empirical and theoretical analyses strongly imply present sharply rising levels of violent death, intensification of deviant behaviors implicated in the spread of AIDS, and the pattern of the AIDS outbreak itself, have been gravely affected, and even strongly determined, by the outcomes of a program of 'planned shrinkage' directed against African-American and Hispanic communities, and implemented through systematic and continuing denial of municipal services--particularly fire extinguishment resources--essential for maintaining urban levels of population density and ensuring community stability. This work complements a recent study by McCord and Freeman [1. New Engl. J. Med. 332, 173, 1990] on Harlem, and suggests the present overburdening of New York's criminal justice system arises from almost exactly the same causes as its accelerating inability to meet demands for acute medical service, so-called 'medical gridlock', in that both are expressions of the increasing social disorganization of poor communities initiated and continued in considerable part by government policy. The critical role played by improper policy in triggering the syndrome suggests ecologically informed interventions, particularly essential service restoration, may hold the potential for great positive impact.

Since the toxicity of diesel exhaust particles (DEP) after intratracheal injection, was suppressed by pretreatment with superoxide dismutase (SOD) modified with polyethylene glycol (Sagai et al. Free Rad. Biol. Med. 14: 37-47; 1993), the possibility that superoxide could be enzymatically and continuously generated from diesel exhaust particles (DEP), was examined. Nicotinamide-adenine dinucleotide phosphate, reduced (NADPH) oxidation was stimulated during interaction of a methanol extract of DEP with the Triton N-101 treated microsomal preparation of mouse lung whereas the cytosolic fraction was less active, suggesting that DEP contains substrates for NADPH-cytochrome P450 reductase (EC 1.6.2.4, P450 reductase) rather than DT-diaphorase. When purified P450 reductase was used as the enzyme source, the turnover value was enhanced approximately 260-fold. Quinones appeared to be served as substrate for P450 reductase because reaction was inhibited by addition of glutathione (GSH) to form those GSH adduct or pretreatment with NaBH4 to reduce those to the hydroxy compounds although a possibility of nitroarenes as the alternative substrates cannot be excluded. A methanol extract of DEP (37.5 micrograms) caused a significant formation of superoxide (3240 nmol/min/mg protein) in the presence of P450 reductase. Electron spin resonance (ESR) experiments revealed that hydroxyl radical was formed as well. The reactive species generated by DEP in the presence of P450 reductase caused DNA scission which was reduced in the presence of superoxide dismutase (SOD), catalase, or hydroxyl radical scavenging agents. Taken together, these results indicate that DEP components, probably quinoid or nitroaromatic structures, that appear to promote DNA damage through the redox cycling based generation of superoxide.

The serotonin transporter (5-HTT) regulates serotonergic neurotransmission and is thought to influence emotion. A 5-HTT-linked polymorphic region (5-HTTLPR) has two common variants, short (s) and long (l). We previously found population and within-family associations between the lower-expressing s allele and neuroticism, a trait related to anxiety, hostility, and depression, on a standard measure (the NEO Personality Inventory, Revised [NEO-PI-R]) in a primarily male population (n=505), and that the s allele was dominant. We investigated this association in a new sample (n=397, 84% female, primarily sib-pairs). The results robustly replicated the 5-HTTLPR neuroticism association, and the dominance of the s allele. Combined data from the two studies (n=902) showed a highly significant association between the s allele and higher NEO Neuroticism both across individuals and within families. Association between genotype and a related measure, Anxiety on the 16PF inventory, was replicated in the new population and within families in the combined sample. Association to another trait, estimated TPQ Harm Avoidance, was not replicated in the new sample but found only within the combined sibship group. Another association found in our original study, between the s allele and lower scores on NEO-PI-R Agreeableness, was also replicated and was more robust in the current and the combined samples. Associations between the functional 5-HTTLPR polymorphism were similar in women and men. These results help to define specific personality features reproducibly associated with 5-HTTLPR genotype. Such associations were strongest for traits defined by the NEO, enhancing the attractiveness of the five-factor personality model in genetic research on complex behavioral dimensions. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:202-216, 2000. Published 2000 Wiley-Liss, Inc.

BACKGROUND

Several biomaterials are available for the purpose of soft tissue augmentation, but none of them has all the properties of the ideal filler material. The recent development of hyaluronic acid gels for dermal implantation give the physician new possibilities of effective treatment in this field.

OBJECTIVE

This study provides a clinical and histological evaluation of safety and efficacy of a cross-linked stabilized non-animal hyaluronic acid gel (Restylane, Q-Med, Uppsala, Sweden) to determine its characteristics, advantages, disadvantages, and side-effects.

METHODS

158 patients were treated with facial intradermal implant of hyaluronic acid gel for augmentation therapy of wrinkles and folds, and for lip augmentation and/or recontouring. The results were evaluated in all patients by subjective judgement by the physician and the patient, and by photographic method at time 0 and after 1, 2, 4 and 8 months from the procedure. In addition, a smaller histological study was carried out in five volunteer patients for a term of 52 weeks to determine the interaction and duration of the material in human healthy skin.

RESULTS

Clinically, both the physicians' and patients' evaluations revealed very satisfactory results, with a global 78.5% and 73.4% respectively of moderate or marked improvement after eight months, independent of the treated area. The photographic evaluation revealed even better results with a 80.4% of moderate or marked improvement after 8 months. The safety evaluation showed a 12.5% of postoperative immediate adverse events, that were localized and transient. There was no evidence of major systemic side effects. Histologically, the product was shown to be long-lasting and well tolerated as judged by histological techniques.

CONCLUSIONS

Stabilized, non-animal, hyaluronic acid gel is well tolerated and effective in augmentation therapy of soft tissues of the face. This material presents several advantages in comparison to previously used injectable biomaterials and expands the arsenal of therapeutic tools in the field of soft tissue augmentation.

Filoviruses are enveloped viruses that cause sporadic outbreaks of severe hemorrhagic fever [CDC, MMWR Morb. Mortal. Wkly. Rep. 50:73-77, 2001; Colebunders and Borchert, J. Infect. 40:16-20, 2000; Colebunders et al., J. Infect. Dis. 196(Suppl. 2):S148-S153, 2007; Geisbert and Jahrling, Nat. Med. 10:S110-S121, 2004]. Previous studies revealed that endosomal cysteine proteases are host factors for ebolavirus Zaire (Chandran et al., Science 308:1643-1645, 2005; Schornberg et al., J. Virol. 80:4174-4178, 2006). In this report, we show that infection mediated by glycoproteins from other phylogenetically diverse filoviruses are also dependent on these proteases and provide additional evidence indicating that they cleave GP1 and expose the binding domain for the critical host factor Niemann-Pick C1. Using selective inhibitors and knockout-derived cell lines, we show that the ebolaviruses Zaire and Cote d'Ivoire are strongly dependent on cathepsin B, while the ebolaviruses Sudan and Reston and Marburg virus are not. Taking advantage of previous studies of cathepsin B inhibitor-resistant viruses (Wong et al., J. Virol. 84:163-175, 2010), we found that virus-specific differences in the requirement for cathepsin B are correlated with sequence polymorphisms at residues 47 in GP1 and 584 in GP2. We applied these findings to the analysis of additional ebolavirus isolates and correctly predicted that the newly identified ebolavirus species Bundibugyo, containing D47 and I584, is cathepsin B dependent and that ebolavirus Zaire-1995, the single known isolate of ebolavirus Zaire that lacks D47, is not. We also obtained evidence for virus-specific differences in the role of cathepsin L, including cooperation with cathepsin B. These studies strongly suggest that the use of endosomal cysteine proteases as host factors for entry is a general property of members of the family Filoviridae.

BACKGROUND

Clinical criteria for aortic dissection are poorly defined. Thus, 35% of aortic dissections remain unsuspected in vivo, and 99% of suspected cases can be refuted.

OBJECTIVE

To identify independent predictors of acute aortic dissection and create a prediction model for facilitated estimation of the individual risk of dissection.

METHODS

Two hundred fifty patients with acute chest pain, back pain, or both; absence of an established differential diagnosis of the pain syndrome; and clinical suspicion of acute aortic dissection were evaluated for the presence of 26 clinical variables in a prospective, observational study. Multivariate analysis was performed to create a prediction model of aortic dissection.

RESULTS

Aortic pain with immediate onset, a tearing or ripping character, or both; mediastinal widening, aortic widening, or both on chest radiography; and pulse differentials, blood pressure differentials, or both (P<.001 for all) were identified as independent predictors of acute aortic dissection. Probability of dissection was low with absence of all 3 variables (7%), intermediate with isolated findings of aortic pain or mediastinal widening (31% and 39%, respectively), and high with isolated pulse or blood pressure differentials or any combination of the 3 variables >> or = 83%). Accordingly, 4% of all dissections were assigned to the low-probability group, 19% to the intermediate-probability group, and 77% to the high-probability group of aortic dissection.

CONCLUSIONS

Assessment of 3 clinical variables permitted identification of 96% of the acute aortic dissections and stratification into high-, intermediate-, and low-probability groupings of disease. With better selection for prompt diagnostic imaging, this prediction model can be used as an aid to improve patient care in aortic dissection. Arch Intern Med. 2000;160:2977-2982

The effect of ramp slope on determination of aerobic parameters from the ramp exercise test. Med. Sci. Sports Exercise, Vol. 14, No. 5, pp. 339-343, 1982. We have previously demonstrated that the four parameters of aerobic function (maximal oxygen uptake (muVO2), VO2 at the anaerobic threshold (theta an), the time constant for VO2 kinetics (tau VO2), and work efficiency (eta)) may all be determined reliably from a single test in which the work rate increases continuously at a constant rate, i.e., ramp. That study, however, utilized a single ramp slope of 50 W X min-1, which may not be appropriate for subjects with very low or very high work tolerances. We therefore studied the effect of different ramp slopes on the determination of these parameters. Ramp slopes of 20, 30, 50, and 100 W X min-1 were generated on a cycle ergometer, and each was assigned randomly to 14 healthy subjects. Ventilatory and gas exchange variables were measured breath-by-breath utilizing on-line digital computation. Ramp slopes of 20, 30, and 50 W X min-1 yielded the same values for each aerobic parameter. The 100 W X min-1 ramp yielded muVO2 and eta an values that were the same as those found for the other ramp slopes, but tau VO2 and eta could not be discerned validly from this ramp slope. We conclude that valid assessment of the four parameters of aerobic function is possible with ramp slopes between 20 and 50 W X min-1; no further information on the parameters is to be gained by prolonging the tests with ramps slower than 20 W X min-1.

BACKGROUND

Accurate measures of health professionals' clinical practice are critically important to guide health policy decisions, as well as for professional self-evaluation and for research-based investigation of clinical practice and process of care. It is often not feasible or ethical to measure behaviour through direct observation, and rigorous behavioural measures are difficult and costly to use. The aim of this review was to identify the current evidence relating to the relationships between proxy measures and direct measures of clinical behaviour. In particular, the accuracy of medical record review, clinician self-reported and patient-reported behaviour was assessed relative to directly observed behaviour.

METHODS

We searched: PsycINFO; MEDLINE; EMBASE; CINAHL; Cochrane Central Register of Controlled Trials; science/social science citation index; Current contents (social & behavioural med/clinical med); ISI conference proceedings; and Index to Theses.

METHODS

empirical, quantitative studies; and examining clinical behaviours. An independent, direct measure of behaviour (by standardised patient, other trained observer or by video/audio recording) was considered the 'gold standard' for comparison. Proxy measures of behaviour included: retrospective self-report; patient-report; or chart-review. All titles, abstracts, and full text articles retrieved by electronic searching were screened for inclusion and abstracted independently by two reviewers. Disagreements were resolved by discussion with a third reviewer where necessary.

RESULTS

Fifteen reports originating from 11 studies met the inclusion criteria. The method of direct measurement was by standardised patient in six reports, trained observer in three reports, and audio/video recording in six reports. Multiple proxy measures of behaviour were compared in five of 15 reports. Only four of 15 reports used appropriate statistical methods to compare measures. Some direct measures failed to meet our validity criteria. The accuracy of patient report and chart review as proxy measures varied considerably across a wide range of clinical actions. The evidence for clinician self-report was inconclusive.

CONCLUSIONS

Valid measures of clinical behaviour are of fundamental importance to accurately identify gaps in care delivery, improve quality of care, and ultimately to improve patient care. However, the evidence base for three commonly used proxy measures of clinicians' behaviour is very limited. Further research is needed to better establish the methods of development, application, and analysis for a range of both direct and proxy measures of behaviour.

OBJECTIVE

To estimate the importance of respiratory and cardiac effects on signal variability found in functional magnetic resonance imaging data recorded from the brainstem.

METHODS

A modified version of the retrospective image correction (RETROICOR) method (Glover et al, [2000] Magn Reson Med 44:162-167) was implemented on resting brainstem echo-planar imaging (EPI) data in 12 subjects. Fourier series were fitted to image data based on cardiac and respiratory recordings (pulseoximetry and respiratory turbine), including multiplicative terms that accounted for interactions between cardiac and respiratory signals. F-tests were performed on residuals produced by regression analysis. Additionally, we evaluated whether modified RETROICOR improved detection of brainstem activation (in 11 subjects) during a finger opposition task.

RESULTS

The optimal model, containing three cardiac (C) and four respiratory (R) harmonics, and one multiplicative (X) term, "3C4R1X," significantly reduced signal variability without overfitting to noise. The application of modified RETROICOR to activation data increased group Z-statistics and reduced putative false-positive activation.

CONCLUSIONS

In addition to cardiac and respiratory effects, their interaction was also a significant source of physiological noise. The modified RETROICOR model improved detection of brainstem activation and would be usefully applied to any study examining this brain region.

OBJECTIVE

Cisplatin is a widely used anti-cancer drug in the treatment of a wide range of tumors; however, its application is limited by nephrotoxicity, which is affected by oxidative stress. We have reported that molecular hydrogen (H(2)) acts as an efficient antioxidant (Ohsawa et al. in Nat Med 13:688-694, 2007). Here we show that hydrogen efficiently mitigates the side effects of cisplatin by reducing oxidative stress.

METHODS

Mice were administered cisplatin followed by inhaling hydrogen gas (1% H(2) in air). Furthermore, instead of inhaling hydrogen gas, we examined whether drinking water containing hydrogen (hydrogen water; 0.8 mM H(2) in water) is applicable by examining oxidative stress, mortality, and body-weight loss. Nephrotoxicity was assessed by morphological changes, serum creatinine and blood urea nitrogen (BUN) levels.

RESULTS

Inhalation of hydrogen gas improved mortality and body-weight loss caused by cisplatin, and alleviated nephrotoxicity. Hydrogen was detected in blood when hydrogen water was placed in the stomach of a rat. Consuming hydrogen water ad libitum also reduced oxidative stress, mortality, and body-weight loss induced by cisplatin in mice. Hydrogen water improved metamorphosis accompanying decreased apoptosis in the kidney, and nephrotoxicity as assessed by serum creatinine and BUN levels. Despite its protective effects against cisplatin-induced toxicity, hydrogen did not impair anti-tumor activity of cisplatin against cancer cell lines in vitro and tumor-bearing mice in vivo.

CONCLUSIONS

Hydrogen has potential for improving the quality of life of patients during chemotherapy by efficiently mitigating the side effects of cisplatin.

Influenza A virus is an important respiratory pathogen that poses a considerable threat to public health each year during seasonal epidemics and even more so when a pandemic strain emerges. Understanding the mechanisms involved in controlling an influenza infection within a host is important and could result in new and effective treatment strategies. Kinetic models of influenza viral growth and decay can summarize data and evaluate the biological parameters governing interactions between the virus and the host. Here we discuss recent viral kinetic models for influenza. We show how these models have been used to provide insight into influenza pathogenesis and treatment, and we highlight the challenges of viral kinetic analysis, including accurate model formulation, estimation of important parameters, and the collection of detailed data sets that measure multiple variables simultaneously. WIREs Syst Biol Med 2011 3 429-445 DOI: 10.1002/wsbm.129

The blood-stage development of malaria parasites is initiated by the invasion of merozoites into susceptible erythrocytes. Specific receptor-ligand interactions must occur for the merozoites to first attach to and then invade erythrocytes. Because the invasion process is essential for the parasite's survival and the merozoite adhesion molecules are exposed on the merozoite surface during invasion, these adhesion molecules are candidates for antibody-dependent malaria vaccines. The Duffy binding protein of Plasmodium vivax belongs to a family of erythrocyte-binding proteins that contain functionally conserved cysteine-rich regions. The amino cysteine-rich regions of these homologous erythrocyte-binding proteins were recently identified for P. vivax, Plasmodium knowlesi, and Plasmodium falciparum as the principal erythrocyte-binding domains (C. Chitnis and L. H. Miller, J. Exp. Med. 180:497-506, 1994, and B. K. L. Sim, C. E. Chitnis, K. Wasniowska, T. J. Hadley, and L. H. Miller, Science 264:1941-1944, 1994). We report that amino acids in this critical ligand domain of the P. vivax Duffy binding protein are hypervariable, but this variability is limited. Hypervariability of the erythrocyte-binding domain suggests that this domain is the target of an effective immune response, but conservation of amino acid substitutions indicates that functional constraints limit this variation. In addition, the amino cysteine-rich region and part of the hydrophilic region immediately following it were the site of repeated homologous recombinations as represented by tandem repeat sequence polymorphisms. Similar polymorphisms have been identified in the same region of the homologous genes of P. falciparum and P. knowlesi, suggesting that there is a common mechanism of recombination or gene conversion that occurs in these Plasmodium genes.

Vibrio cholerae represents both an environmental pathogen and a widely distributed microbial species comprised of closely related strains occurring in the tropical to temperate coastal ocean across the globe (Colwell RR, Science 274:2025-2031, 1996; Griffith DC, Kelly-Hope LA, Miller MA, Am. J. Trop. Med. Hyg. 75:973-977, 2006; Reidl J, Klose KE, FEMS Microbiol. Rev. 26:125-139, 2002). However, although this implies dispersal and growth across diverse environmental conditions, how locally successful populations assemble from a possibly global gene pool, relatively unhindered by geographic boundaries, remains poorly understood. Here, we show that environmental Vibrio cholerae possesses two, largely distinct gene pools: one is vertically inherited and globally well mixed, and the other is local and rapidly transferred across species boundaries to generate an endemic population structure. While phylogeographic analysis of isolates collected from Bangladesh and the U.S. east coast suggested strong panmixis for protein-coding genes, there was geographic structure in integrons, which are the only genomic islands present in all strains of V. cholerae (Chun J, et al., Proc. Natl. Acad. Sci. U. S. A. 106:15442-15447, 2009) and are capable of acquiring and expressing mobile gene cassettes. Geographic differentiation in integrons arises from high gene turnover, with acquisition from a locally co-occurring sister species being up to twice as likely as exchange with conspecific but geographically distant V. cholerae populations. IMPORTANCE Functional predictions of integron genes show the predominance of secondary metabolism and cell surface modification, which is consistent with a role in competition and predation defense. We suggest that the integron gene pool's distinctness and tempo of sharing are adaptive in allowing rapid conversion of genomes to reflect local ecological constraints. Because the integron is frequently the main element differentiating clinical strains (Chun J, et al., Proc. Natl. Acad. Sci. U. S. A. 106:15442-15447, 2009) and its recombinogenic activity is directly stimulated by environmental stresses (Guerin E, et al., Science 324:1034, 2009), these observations are relevant for local emergence and subsequent dispersal.

A 40-amino-acid sequence located in the nonstructural 5A (NS5A) protein of hepatitis C virus genotype 1b (HCV-1b) was recently suggested to be the interferon sensitivity-determining region (ISDR), because HCV-1b strains with an ISDR amino acid sequence identical to that of the prototype strain HCV-J were found to be resistant to alpha interferon (IFN-alpha) whereas strains with amino acid substitutions were found to be sensitive (N. Enomoto, I. Sakuma, Y. Asahina, M. Kurosaki, T. Murakami, C. Yamamoto, N. Izumi, F. Marumo, and C. Sato, J. Clin. Invest. 96:224-230, 1995; N. Enomoto, I. Sakuma, Y. Asahina, M. Kurosaki, T. Murakami, C. Yamamoto, Y. Ogura, N. Izumi, F. Marumo, and C. Sato, N. Engl. J. Med. 334:77-81, 1996). We used single-strand conformation polymorphism (SSCP) analysis, combined with cloning and sequencing strategies, to characterize NS5A quasispecies in HCV-1b-infected patients and determine the relationships between pre- and posttreatment NS5A quasispecies mutations and the IFN-alpha sensitivity of HCV-1b. The serine residues involved in phosphorylation of NS5A protein were highly conserved both in the various patients and in quasispecies in a given patient, suggesting that phosphorylation is important in NS5A protein function. A hot spot for amino acid substitutions was found at positions 2217 to 2218; it could be the result of either strong selection pressure or tolerance to these amino acid replacements. The proportion of synonymous mutations was significantly higher than the proportion of nonsynonymous mutations, suggesting that genetic variability in the region studied was the result of high mutation rates and viral replication kinetics rather than of positive selection. Sustained HCV RNA clearance was associated with low viral load and low nucleotide sequence entropy, suggesting (i) that the replication kinetics when treatment is started plays a critical role in HCV-1b sensitivity to IFN-alpha and (ii) that HCV-1b resistance to IFN-alpha could be conferred by numerous and/or related mutations that could be patient specific and located at different positions throughout the viral genome and could allow escape variants to be selected by IFN-alpha-stimulated immune responses. No NS5A sequence appeared to be intrinsically resistant or sensitive to IFN-alpha, but the HCV-J sequence was significantly more frequent in nonresponder quasispecies than in sustained virological responder quasispecies, suggesting that the balance between NS5A quasispecies sequences in infected patients could have a subtle regulatory influence on HCV replication.

OBJECTIVE

To test the hypothesis that use of antihypertensive medication is associated with lower Alzheimer disease (AD) neuropathology.

METHODS

This was a postmortem study of 291 brains limited to those with normal neuropathology or with uncomplicated AD neuropathology (i.e., without other dementia-associated neuropathology) in persons with or without hypertension (HTN) who were and were not treated with antihypertensive medications. Neuritic plaque (NP) and neurofibrillary tangle (NFT) densities, quantified in selected brain regions according to the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuropathologic criteria, with additional cortical NP counts, yielded 24 neuropathologic regional measures or summaries. Medicated hypertension (HTN-med; n = 77), nonmedicated HTN (HTN-nomed; n = 42), and non-HTN (no-HTN; n = 172) groups were compared by analyses of variance.

RESULTS

The HTN-med group had significantly less neuropathology than the no-HTN group. The no-HTN group averaged over 50% higher mean NP and NFT ratings, and double the mean NP count, of the HTN-med group. The HTN-nomed group had significantly more neuropathology than the HTN-med group, but not significantly less than the no-HTN group.

CONCLUSIONS

There was substantially less Alzheimer disease (AD) neuropathology in the medicated hypertension group than the nonhypertensive group, which may reflect a salutary effect of antihypertensive medication against AD-associated neuropathology.

Previous studies correlated the presence of a 200-kDa protein on the surface of Moraxella catarrhalis with the ability of this organism to agglutinate human erythrocytes (M. Fitzgerald, R. Mulcahy, S. Murphy, C. Keane, D. Coakley, and T. Scott, FEMS Immunol. Med. Microbiol. 18:209-216, 1997). In the present study, the gene encoding the 200-kDa protein (designated Hag) of M. catarrhalis strain O35E was subjected to nucleotide sequence analysis and then was inactivated by insertional mutagenesis. The isogenic hag mutant was unable to agglutinate human erythrocytes and lost its ability to autoagglutinate but was still attached at wild-type levels to several human epithelial cell lines. The hag mutation also eliminated the ability of this mutant strain to bind human immunoglobulin D. The presence of the Hag protein on the M. catarrhalis cell surface, as well as that of the UspA1 and UspA2 proteins (C. Aebi, I. Maciver, J. L. Latimer, L. D. Cope, M. K. Stevens, S. E. Thomas, G. H. McCracken, Jr., and E. J. Hansen, Infect. Immun. 65:4367-4377, 1997), was investigated by transmission electron and cryoimmunoelectron microscopy. Wild-type M. catarrhalis strain O35E possessed a dense layer of surface projections, whereas an isogenic uspA1 uspA2 hag triple mutant version of this strain did not possess any detectable surface projections. Examination of a uspA1 uspA2 double mutant that expressed the Hag protein revealed the presence of a relatively sparse layer of surface projections, similar to those seen on a uspA2 hag mutant that expressed UspA1. In contrast, a uspA1 hag mutant that expressed UspA2 formed a very dense layer of relatively short surface projections. These results indicate that the surface-exposed Hag protein and UspA1 and UspA2 have the potential to interact both with each other and directly with host defense systems.

Elevated coexpression of colony-stimulating factor receptor (CSF-1R) and its ligand, CSF-1, correlates with invasiveness and poor prognosis of a variety of epithelial tumors (Kacinski, B.M. 1995. Ann. Med. 27:79-85). Apart from recruitment of macrophages to the tumor site, the mechanisms by which CSF-1 may potentiate invasion are poorly understood. We show that autocrine CSF-1R activation induces hyperproliferation and a profound, progressive disruption of junctional integrity in acinar structures formed by human mammary epithelial cells in three-dimensional culture. Acini coexpressing receptor and ligand exhibit a dramatic relocalization of E-cadherin from the plasma membrane to punctate intracellular vesicles, accompanied by its loss from the Triton-insoluble fraction. Interfering with Src kinase activity, either by pharmacological inhibition or mutation of the Y561 docking site on CSF-1R, prevents E-cadherin translocation, suggesting that CSF-1R disrupts cell adhesion by uncoupling adherens junction complexes from the cytoskeleton and promoting cadherin internalization through a Src-dependent mechanism. These findings provide a mechanistic basis whereby CSF-1R could contribute to invasive progression in epithelial cancers.

RSV is the primary cause of hospitalisation in the first year of life for children in most parts of the world, and nearly 100% of children in the USA are infected with the virus by 2 to 3 years of age. The agent is an enveloped RNA virus with a non-segmented single-stranded negative-sense genome. The viral genome encodes 8 structural and 2 non-structural proteins. Important structural proteins include the fusion (F) protein and the attachment (G) protein which are essential for viral penetration and attachment to the host cells. Both proteins are important in development of immune responses. The virus is estimated to cause 3000 to 4000 deaths annually. Primary infections are as a rule symptomatic. The spectrum of clinical manifestations ranges from mild upper tract illness, infection in middle ear which progresses to acute otitis media, croup, to apnoea in premature infants, pneumonia and bronchiolitis. Premature babies born at 30-35 weeks of gestation, infants with cyanotic congenital heart disease, HIV-infected subjects, and patients on intensive immunosuppressive therapy especially after bone marrow transplant are considered to be at risk for increased mortality and morbidity during RSV infection. The virus does not normally replicate outside of the bronchopulmonary tree and the infection is exquisitely restricted to the respiratory mucosa. However, development of extrapulmonary disease has been observed in certain T and B cell immunodeficiency states. The association of RSV with asthma and reversible reactive airway disease in early childhood has attracted significant attention. Recurrent wheezing for up to 5 to 7 years of age and established airway disease has been observed in a significant number of children with a strong family history of allergy, after primary infection or reinfection with RSV. Immune response to primary infection is relatively small but on reinfection, a significant booster effect with sustained immunologic reactivity is observed in serum and respiratory mucosa. Both CD(4)- and CD(8)-specific as well as Th(1)- and Th(2)-cell specific immune responses have been observed during human infection. In addition, proinflammatory as well as immunoregulatory cytokines and chemokines are induced in the respiratory tract after natural and induced (in vitro) infection. Significant progress has been made in understanding the role of Th(1) vs. Th(2), IgE, viral induced cytokines and chemokines in the mechanisms of pathogenesis of the disease, development of wheezing and in the prevention and treatment of the infection and its sequelae. Respiratory syncytial virus (RSV) is one of the commonest human viral infections, and virtually every child is infected by the third birthday. Because of its restricted mucosal immunopathology, and frequent association with bronchial hyperreactivity and development of wheezing, RSV has served as an important model to investigate mechanisms of mucosal immune responses and development of mucosal disease following infection. The importance of RSV in bronchopulmonary disease and development of bronchial hyperreactivity has been the focus of several recent symposia [Kimpen JL, Simoes EAF. Am J Respir Crit Care Med 2001; 163:S1-S6]. This brief report will only summarise, based on selected references, the historical landmarks of its discovery and current understanding of the mechanisms of immunity, and their possible role in the pathogenesis of bronchopulmonary disease.

Reporting and sharing pharmacogenetic test results across clinical laboratories and electronic health records is a crucial step toward the implementation of clinical pharmacogenetics, but allele function and phenotype terms are not standardized. Our goal was to develop terms that can be broadly applied to characterize pharmacogenetic allele function and inferred phenotypes.

Terms currently used by genetic testing laboratories and in the literature were identified. The Clinical Pharmacogenetics Implementation Consortium (CPIC) used the Delphi method to obtain a consensus and agree on uniform terms among pharmacogenetic experts.

Experts with diverse involvement in at least one area of pharmacogenetics (clinicians, researchers, genetic testing laboratorians, pharmacogenetics implementers, and clinical informaticians; n = 58) participated. After completion of five surveys, a consensus (>70%) was reached with 90% of experts agreeing to the final sets of pharmacogenetic terms.

The proposed standardized pharmacogenetic terms will improve the understanding and interpretation of pharmacogenetic tests and reduce confusion by maintaining consistent nomenclature. These standard terms can also facilitate pharmacogenetic data sharing across diverse electronic health care record systems with clinical decision support.Genet Med 19 2, 215-223.