bluuebunny/crossref_metadata_2025 huggingface dataset:
Geographic Information Systems and Applied Spatial Statistics Are Efficient Tools to Study Hansen's Disease (Leprosy) and to Determine Areas of Greater Risk of Disease
Authors: Queiroz José Wilton , Dias Gutemberg H. , Nobre Maurício Lisboa , De Sousa Dias Márcia C. , Araújo Sérgio F. , Barbosa James D. , da Trindade-Neto Pedro Bezerra , Blackwell Jenefer M. , Jeronimo Selma M. B.
Published: February 2010

Applied Spatial Statistics used in conjunction with geographic information systems (GIS) provide an efficient tool for the surveillance of diseases. Here, using these tools we analyzed the spatial distribution of Hansen's disease in an endemic area in Brazil. A sample of 808 selected from a universe of 1,293 cases was geocoded in Mossoró, Rio Grande do Norte, Brazil. Hansen's disease cases were not distributed randomly within the neighborhoods, with higher detection rates found in more populated districts. Cluster analysis identified two areas of high risk, one with a relative risk of 5.9 (P = 0.001) and the other 6.5 (P = 0.001). A significant relationship between the geographic distribution of disease and the social economic variables indicative of poverty was observed. Our study shows that the combination of GIS and spatial analysis can identify clustering of transmissible disease, such as Hansen's disease, pointing to areas where intervention efforts can be targeted to control disease.
Experimental Infections of Oryzomys couesi with Sympatric Arboviruses from Mexico
Authors: Deardorff Eleanor R. , Forrester Naomi L. , Travassos da Rosa Amelia P. , Estrada-Franco Jose G. , Navarro-Lopez Roberto , Tesh Robert B. , Weaver Scott C.
Published: February 2010

Coues rice rat (Oryzomys couesi), a species abundant throughout Central America, was evaluated experimentally for the ability to serve as an amplifying host for three arboviruses: Patois (Bunyaviridae, Orthobunyavirus), Nepuyo (Orthobunyavirus), and Venezuelan equine encephalitis virus subtype ID (Togaviridae, Alphavirus). These three viruses have similar ecologies and are known to co-circulate in nature. Animals from all three cohorts survived infection and developed viremia with no apparent signs of illness and long-lasting antibodies. Thus, O. couesi may play a role in the general maintenance of these viruses in nature.
Disentangling the Effect of Local and Global Spatial Variation on a Mosquito-Borne Infection in a Neotropical Heterogeneous Environment
Authors: Grillet María-Eugenia , Barrera Roberto , Martínez Juan-Eudes , Berti Jesús , Fortin Marie-Josée
Published: February 2010

Mosquito-borne pathogen transmission exhibits spatial-temporal variability caused by ecological interactions acting at different scales. We used local spatial statistics and geographically weighted regression (GWR) to determine the spatial pattern of malaria incidence and persistence in northeastern Venezuela. Seven to 11 hot spots of malaria transmission were detected by using local spatial statistics, although disease persistence was explained only for four of those hot spots. The GWR models greatly improved predictions of malaria risk compared with ordinary least squares (OLS) regression models. Malaria incidence was largely explained by the proximity to and number of Anopheles aquasalis habitats nearby (1–3 km), and low-elevation terrains. Disease persistence was associated with greater human population density, lower elevations, and proximity to aquatic habitats. However, there was significant local spatial variation in the relationship between malaria and environmental variables. Spatial modeling improves the understanding of the causal factors operating at several scales in the transmission of malaria.
Transmission Potential of Two Chimeric Western Equine Encephalitis Vaccine Candidates in Culex tarsalis
Authors: Kenney Joan L. , Adams A. Paige , Weaver Scott C.
Published: February 2010

Western equine encephalitis virus (WEEV) is a zoonotic alphavirus that circulates in western North America between passerine birds and mosquitoes, primarily Culex tarsalis. Since it was isolated in 1930, WEEV has caused tens of thousands of equine deaths in addition to thousands of human cases. In addition because WEEV is a virus of agricultural importance in addition to a public health threat, we developed two live-attenuated chimeric vaccine candidates that have been shown to be immunogenic and efficacious in mouse models. Vaccine candidate strains were developed by inserting the structural protein genes of WEEV strain McMillan (McM) or CO92-1356 into a Sindbis virus (SINV) strain AR339 backbone. The SIN/McM chimera also derived the N-terminal half of its capsid gene from a North American eastern equine encephalitis virus (EEEV) strain FL39-939 (henceforth referred to as SIN/EEE/McM). Although these vaccines do not generate viremia in mice, we further assessed their safety by exposing Cx. tarsalis to artificial blood meals containing high viral titers of each vaccine candidate. Both viruses exhibited a decreased rate of infection, dissemination, and transmission potential compared with the parental alphaviruses. Specifically, SIN/CO92 infected 37% of mosquitoes and disseminated in 8%, but failed to reach the saliva of the mosquitoes. In contrast, the SIN/EEE/McM virus was unable to infect, disseminate, or be transmitted in the saliva of any mosquitoes. These findings suggest that both vaccine candidates are less competent than the parental strains to be transmitted by the primary mosquito vector, Cx. tarsalis, and are unlikely to be reintroduced into a natural WEEV transmission cycle.
Hospital-Based Surveillance for Japanese Encephalitis at Four Sites in Bangladesh, 2003–2005
Authors: Hossain M. Jahangir , Gurley Emily S. , Montgomery Susan , Petersen Lyle , Sejvar James , Fischer Marc , Panella Amanda , Powers Ann M. , Nahar Nazmun , Rafique Uddin A. K. M. , Rahman M. Ekhlasur , Saifuddin Ekram A. R. M. , Luby Stephen P. , Breiman Robert F.
Published: February 2010

We investigated the epidemiology and etiology of encephalitis at four tertiary hospitals in Bangladesh during 2003–2005. Patients who met a clinical case definition for acute encephalitis and had cerebrospinal fluid (CSF) pleocytosis were eligible for enrollment; a standardized sampling pattern was used to enroll eligible patients. Recent Japanese encephalitis virus (JEV) infection was defined by presence of IgM antibodies against JEV in CSF or serum. Twenty (4%) of 492 cases had laboratory evidence of recent JEV infection; two died. All JE cases occurred during May–December, and cases were identified among all age groups. All cases resided in rural areas. Fifteen patients were re-assessed 4–6 weeks after hospitalization; 5 (33%) patients had physical disabilities and 7 (47%) reported cognitive difficulties. Infection with JEV is clearly an etiology of encephalitis in Bangladesh. Population-based studies to quantify burden of disease could assess options for targeted immunization programs.
Environmental Risk Factors for the Incidence of American Cutaneous Leishmaniasis in a Sub-Andean Zone of Colombia (Chaparral, Tolima)
Authors: Valderrama-Ardila Carlos , Alexander Neal , Ferro Cristina , Cadena Horacio , Marín Dairo , Holford Theodore R. , Munstermann Leonard E. , Ocampo Clara B.
Published: February 2010

Environmental risk factors for cutaneous leishmaniasis were investigated for the largest outbreak recorded in Colombia. The outbreak began in 2003 in Chaparral, and in the following five years produced 2,313 cases in a population of 56,228. Candidate predictor variables were land use, elevation, and climatic variables such as mean temperature and precipitation. Spatial analysis showed that incidence of cutaneous leishmaniasis was higher in townships with mean temperatures in the middle of the county's range. Incidence was independently associated with higher coverage with forest or shrubs (2.6% greater for each additional percent coverage, 95% credible interval [CI] = 0.5–4.9%), and lower population density (22% lower for each additional 100 persons/km2, 95% CI = 7–41%). The extent of forest or shrub coverage did not show major changes over time. These findings confirmed the roles of climate and land use in leishmaniasis transmission. However, environmental variables were not sufficient to explain the spatial variation in incidence.
Efficacy of Waterless Hand Hygiene Compared with Handwashing with Soap: A Field Study in Dar es Salaam, Tanzania
Authors: Pickering Amy J. , Boehm Alexandria B. , Mwanjali Mathew , Davis Jennifer
Published: February 2010

Effective handwashing with soap requires reliable access to water supplies. However, more than three billion persons do not have household-level access to piped water. This research addresses the challenge of improving hand hygiene within water-constrained environments. The antimicrobial efficacy of alcohol-based hand sanitizer, a waterless hand hygiene product, was evaluated and compared with handwashing with soap and water in field conditions in Dar es Salaam, Tanzania. Hand sanitizer use by mothers resulted in 0.66 and 0.64 log reductions per hand of Escherichia coli and fecal streptococci, respectively. In comparison, handwashing with soap resulted in 0.50 and 0.25 log reductions per hand of E. coli and fecal streptococci, respectively. Hand sanitizer was significantly better than handwashing with respect to reduction in levels of fecal streptococci (P = 0.01). The feasibility and health impacts of promoting hand sanitizer as an alternative hand hygiene option for water-constrained environments should be assessed.
The Contribution of Bats to Leptospirosis Transmission in São Paulo City, Brazil
Authors: Franco Bessa Thirsa Álvares , Spichler Anne , Berardis Chapola Érica G. , Husch Alfred Christian , Fernandes de Almeida Marilene , Sodré Miriam Martos , Mouriz Savani Elisa S. M. , Veiga Sacramento Débora R. , Vinetz Joseph M.
Published: February 2010

The biodiversity of potential leptospiral reservoir hosts is lower in urban than in rural environments. Previous data indicate the potential for bats to act as carriers of Leptospira in regions such as the Amazon of South America and in Australia. Yet, little is known about the contribution of bats to leptospirosis in urban environments in South America. This study aimed to test the hypothesis that bats infected with Leptospira are sources of leptospirosis transmission to humans in São Paulo City, Brazil. Six of 343 bats caught in different districts within the city of Sao Paulo (182 insectivorous, 161 frugivorous or nectarivorous) were polymerase chain reaction (PCR) positive for pathogenic Leptospira; no seropositive bats were found. That few renal carriers of Leptospira were found in the city of Sao Paulo suggests that bats are not important in the transmission of leptospirosis to humans in this, and possibly other urban settings.
Burden of Malaria during Pregnancy at the Time of IPTp/SP Implementation in Gabon
Authors: Bouyou-Akotet Marielle K. , Nzenze-Afene Solange , Ngoungou Edgard B. , Kendjo Eric , Owono-Medang Mathieu , Lekana-Douki Jean-Bernard , Obono-Obiang Ghislaine , Mounanga Mathieu , Kombila Maryvonne
Published: February 2010

The new recommendations to prevent malaria in pregnant women have recently been implemented in Gabon. There is little information on the pregnancy indicators that are useful for their evaluation. A cross-sectional study for the assessment of the prevalence of peripheral, placental, and cord malaria and anemia among delivering women was performed at the largest public hospital of Gabon. Malaria prevalence was 34.4%, 53.6%, and 18.2% for maternal peripheral, placental, and cord blood respectively, with no difference between primigravidae and multigravidae. Submicroscopic infections were frequent and concerned all the positive cord samples. Maternal peripheral, late placental, and cord infections were all associated with a reduced mean birth weight in primigravidae (P = 0.02). Anemia prevalence was 53%, low birth rate was 13%, and prematurity was 25%. The use of intermittent preventive treatment with sulfadoxine-pyrimethamine (greater than or equal to one dose) combined with bed net was associated with a reduction in infection only in multigravidae and with a reduced risk of maternal anemia.
Evaluation of a New Disinfection Approach: Efficacy of Chlorine and Bromine Halogenated Contact Disinfection for Reduction of Viruses and Microcystin Toxin
Authors: Coulliette Angela D. , Peterson Lauren A. , Mosberg Joshua A. W. , Rose Joan B.
Published: February 2010

Contaminated drinking water is responsible for causing diarrheal diseases that kill millions of people a year. Additionally, toxin-producing blue-green algae associated with diarrhea and neurologic effects continues to be an issue for many drinking water supplies. Disinfection has been used to reduce these risks. A novel gravity-fed household drinking water system with canisters containing N-halamine bromine or chlorine media was challenged with MS2 bacteriophage and microcystin. Chlorine and bromine systems were effective against this virus, with an mean ± SE reduction of 2.98 ± 0.26 log10 and 5.02 ± 0.19 log10, respectively. Microcystin toxin was reduced by 27.5% and 88.5% to overall mean ± SE concentrations of 1,600 ± 98 ng/L and 259 ± 50 ng/L for the chlorine and bromine canisters, respectively. Only the bromine units consistently produced microcystin effluent < 1,000 ng/L (the World Health Organization recommended level) when challenged with 2,500 ng/L and consistently surpassed the U.S. Environmental Protection Agency virus reduction goal of 99.99%.
Development of Cryptosporidium parvum-Induced Gastrointestinal Neoplasia in Severe Combined Immunodeficiency (SCID) Mice: Severity of Lesions Is Correlated with Infection Intensity
Authors: Certad Gabriela , Creusy Colette , Ngouanesavanh Tramy , Guyot Karine , Gantois Nausicaa , Mouray Anthony , Chassat Thierry , Flament Nicolas , Fleurisse Laurence , Pinon Anthony , Delhaes Laurence , Dei-Cas Eduardo
Published: February 2010

We reported previously that Cryptosporidium parvum was able to induce intestinal tumors in severe combined immunodeficiency (SCID) mice treated with corticoids. To further characterize this Cryptosporidium-induced cell transformation, SCID mice treated with dexamethasone were challenged with C. parvum oocysts, and euthanatized sequentially after infection for histologic examination. Ki-67 was used as a marker of cellular proliferation. Our previous results were confirmed, and it was also found that mice receiving higher inocula (106–107) experienced more severe neoplastic development. Additionally, neoplastic changes were observed not only in the caecum but also in the stomach and duodenum of some animals. Interestingly, SCID mice (6/6) inoculated with 105–107 oocysts showed high grade intraepithelial neoplasia or adenomas with high grade dysplasia in the caecum after Day 46 post-infection (PI). Immunohistochemistry for Ki-67 staining indicated the neoplastic process associated to cryptosporidiosis, and evidenced the first immunohistochemical alterations at early stages of the process, even at 3 weeks PI.
Leishmania Infection: Laboratory Diagnosing in the Absence of a “Gold Standard”
Authors: Rodríguez-Cortés Alhelí , Ojeda Ana , Francino Olga , López-Fuertes Laura , Timón Marcos , Alberola Jordi
Published: February 2010

There is no gold standard for diagnosing leishmaniases. Our aim was to assess the operative validity of tests used in detecting Leishmania infection using samples from experimental infections, a reliable equivalent to the classic definition of gold standard. Without statistical differences, the highest sensitivity was achieved by protein A (ProtA), immunoglobulin (Ig)G2, indirect fluorescenece antibody test (IFAT), lymphocyte proliferation assay, quantitative real-time polymerase chain reaction of bone marrow (qPCR-BM), qPCR-Blood, and IgG; and the highest specificity by IgG1, IgM, IgA, qPCR-Blood, IgG, IgG2, and qPCR-BM. Maximum positive predictive value was obtained simultaneously by IgG2, qPCR-Blood, and IgG; and maximum negative predictive value by qPCR-BM. Best positive and negative likelihood ratios were obtained by IgG2. The test having the greatest, statistically significant, area under the receiver operating characteristics curve was IgG2 enzyme-linked immunosorbent assay (ELISA). Thus, according to the gold standard used, IFAT and qPCR are far from fulfilling the requirements to be considered gold standards, and the test showing the highest potential to detect Leishmania infection is Leishmania-specific ELISA IgG2.
Is Mosquito Larval Source Management Appropriate for Reducing Malaria in Areas of Extensive Flooding in The Gambia? A Cross-over Intervention Trial
Authors: Majambere Silas , Pinder Margaret , Fillinger Ulrike , Ameh David , Conway David J. , Green Clare , Jeffries David , Jawara Musa , Milligan Paul J. , Hutchinson Robert , Lindsay Steven W.
Published: February 2010

Larviciding to control malaria was assessed in rural areas with extensive seasonal flooding. Larval and adult mosquitoes and malaria incidence were surveyed routinely in four 100-km2 areas either side of the Gambia River. Baseline data were collected in 2005. Microbial larvicide was applied to all water bodies by hand application with water-dispersible granular formulations and corn granules weekly from May to November in two areas in 2006 and in the other two areas in 2007 in a cross-over design. The intervention was associated with a reduction in habitats with late stage anopheline larvae and an 88% reduction in larval densities (P < 0.001). The effect of the intervention on mosquito densities was not pronounced and was confounded by the distance of villages to the major breeding sites and year (P = 0.002). There was no reduction in clinical malaria or anemia. Ground applications of non-residual larvicides with simple equipment are not effective in riverine areas with extensive flooding, where many habitats are poorly demarcated, highly mobile, and inaccessible on foot.
Evaluation of a Rapid Qualitative Enzyme Chromatographic Test for Glucose-6-Phosphate Dehydrogenase Deficiency
Authors: Tinley Kathleen E. , Loughlin Anita M. , Jepson Anne , Barnett Elizabeth D.
Published: February 2010

Rapid determination of glucose-6-phosphate dehydrogenase (G6PD) status is desirable when it is necessary to use a drug contraindicated in G6PD-deficient persons, such as use of primaquine for malaria prevention or treatment. The purpose of this study was to compare a new, rapid, qualitative enzyme chromatographic test for deficiency of G6PD to a standard reference method. Samples from 196 G6PD-normal persons and 50 G6PD-deficient persons were evaluated. The sensitivity of the experimental rapid test was 0.98 and the specificity was 0.98 using specimens preserved in heparin, and 0.98 and 0.97, respectively, for specimens preserved in EDTA. Positive and negative predictive values were 0.72 and 1.00, respectively, for the test for heparinized specimens and 0.65 and 1.00, respectively, for the EDTA-preserved samples. This rapid test for G6PD deficiency is a sensitive method for screening of G6PD deficiency that requires minimal training and equipment and enables rapid identification of G6PD-deficient persons.
Retinal Hemorrhage in Plasmodium vivax Malaria
Authors: Lee Ji Hwan , Chin Hee Seung , Chung Moon-Hyun , Moon Yeon Sook
Published: February 2010

Retinal hemorrhage is a frequently observed sign in Plasmodium falciparum infection. In Plasmodium vivax infection, however, retinal hemorrhage is very rare; only five cases have been reported in the literature. In this case report, we review the literature and the case of 52-year-old man who had retinal hemorrhages in P. vivax infection. We analyzed the structural characteristics of the lesions using fluorescein angiography and spectral-domain optical coherence tomography. Physicians should be aware of the possibility of retinal hemorrhage in malaria patients, even those with P. vivax infection, and should consider a diagnosis of malaria in a patient with unexplained retinal hemorrhage and fever.
A Non-Radioactive DAPI-based High-Throughput In Vitro Assay to Assess Plasmodium falciparum Responsiveness to Antimalarials—Increased Sensitivity of P. falciparum to Chloroquine in Senegal
Authors: Ndiaye Daouda , Patel Vishal , Demas Allison , LeRoux Michele , Ndir Omar , Mboup Souleymane , Clardy Jon , Lakshmanan Viswanathan , Daily Johanna P. , Wirth Dyann F.
Published: February 2010

The spread of Plasmodium falciparum drug resistance is outpacing new antimalarial development and compromising effective malaria treatment. Combination therapy is widely implemented to prolong the effectiveness of currently approved antimalarials. To maximize utility of available drugs, periodic monitoring of drug efficacy and gathering of accurate information regarding parasite-sensitivity changes are essential. We describe a high-throughput, non-radioactive, field-based assay to evaluate in vitro antimalarial drug sensitivity of P. falciparum isolates from 40 Senegalese patients. Compared with earlier years, we found a significant decrease in chloroquine in vitro and in genotypic resistances (> 50% and > 65%, respectively, in previous studies) with only 23% of isolates showing resistance. This is possibly caused by a withdrawal of chloroquine from Senegal in 2002. We also found a range of artemisinin responses. Prevalence of drug resistance is dynamic and varies by region. Therefore, the implementation of non-radioactive, robust, high-throughput antimalarial sensitivity assays is critical for defining region-specific prophylaxis and treatment guidelines.
Travel and Travelers' Diarrhea in Patients with Irritable Bowel Syndrome
Authors: DuPont Herbert L. , Galler Greg , Garcia-Torres Francisco , DuPont Andrew W. , Greisinger Anthony , Jiang Zhi-Dong
Published: February 2010

This study evaluated occurrence of travel and travelers' diarrhea in patients with irritable bowel syndrome (IBS). A survey was mailed to 591 patients of a clinical practice who had IBS. Based on survey responses, patients were categorized as having IBS, post-infectious IBS (PI-IBS), unclassified functional bowel disorder (UFBD), or post-infectious UFBD (PI-UFBD). Of 201 persons who returned questionnaires meeting inclusion criteria, 57.7%, 11.4%, 24.9%, and 6.0% had IBS, UFBD, PI-IBS, and PI-UFBD, respectively. Travel during six months before illness onset was more common in patients with PI-IBS or PI-UFBD than in persons with idiopathic IBS or UFBD (P = 0.006). Survey results demonstrated that 16.1% of post-infectious bowel disorder cases and 7.5% of overall IBS cases in a general medical population developed chronic disease within six months of an international trip. Symptoms of established functional bowel disorder in each clinical category were shown to worsen after travel-related acute diarrhea.
Geographic Structure of Plasmodium vivax: Microsatellite Analysis of Parasite Populations from Sri Lanka, Myanmar, and Ethiopia
Authors: Gunawardena Sharmini , Karunaweera Nadira D. , Ferreira Marcelo U. , Phone-Kyaw Myatt , Pollack Richard J. , Alifrangis Michael , Rajakaruna Rupika S. , Konradsen Flemming , Amerasinghe Priyanie H. , Schousboe Mette L. , Galappaththy Gawrie N. L. , Abeyasinghe Rabindra R. , Hartl Daniel L. , Wirth Dyann F.
Published: February 2010

Genetic diversity and population structure of Plasmodium vivax parasites can predict the origin and spread of novel variants within a population enabling population specific malaria control measures. We analyzed the genetic diversity and population structure of 425 P. vivax isolates from Sri Lanka, Myanmar, and Ethiopia using 12 trinucleotide and tetranucleotide microsatellite markers. All three parasite populations were highly polymorphic with 3–44 alleles per locus. Approximately 65% were multiple-clone infections. Mean genetic diversity (HE) was 0.7517 in Ethiopia, 0.8450 in Myanmar, and 0.8610 in Sri Lanka. Significant linkage disequilibrium was maintained. Population structure showed two clusters (Asian and African) according to geography and ancestry. Strong clustering of outbreak isolates from Sri Lanka and Ethiopia was observed. Predictive power of ancestry using two-thirds of the isolates as a model identified 78.2% of isolates accurately as being African or Asian. Microsatellite analysis is a useful tool for mapping short-term outbreaks of malaria and for predicting ancestry.
Phase‐Transfer‐Catalyzed Intramolecular Cyclization of ortho‐Alkynyl Phenyl Ether Derivatives for Synthesis of 2,3‐Disubstituted Benzo[b]furans
Authors: Hu Jie , Wu Lu‐Yong , Wang Xiang‐Chuan , Hu Yuan‐Yuan , Niu Yan‐Ning , Liu Xue‐Yuan , Yang Shangdong , Liang Yong‐Min
Published: February 2010

A variety of substituted benzo[b]furans are readily prepared in good to excellent yields under the mild reaction conditions from o‐(1‐alkynylphenoxy)‐1‐phenylethanone under phase‐transfer catalysis (PTC). This methodology accommodates simple experimental operations, inexpensive and environmentally benign catalysts, metal catalyst‐free conditions, facile reagents and the possibility to conduct large‐scale preparations. The development of carbon‐carbon bond formation processes via an overall structural isomerization represents the most atom‐economical approach.
Aerobic Oxidation of Primary Aliphatic Alcohols to Aldehydes Catalyzed by a Palladium(II) Polyoxometalate Catalyst
Authors: Barats Delina , Neumann Ronny
Published: February 2010

A hexadecyltrimethylammonium salt of a “sandwich” type polyoxometalate has been used as a ligand to attach a palladium(II) center. This Pd‐POM compound was an active catalyst for the fast aerobic oxidation of alcohols. The unique property of this catalyst is its significant preference for the oxidation of primary versus secondary aliphatic alcohols. Since no kinetic isotope effect was observed for the dehydrogenation step, this may be the result of the intrinsically higher probability for oxidation of primary alcohols attenuated by steric factors as borne out by the higher reactivity of 1‐octanol versus 2‐ethyl‐1‐hexanol. The reaction is highly selective to aldehyde with little formation of carboxylic acid; autooxidation is inhibited. No base is required to activate the alcohol. The fast reactions appear to be related to the electron‐acceptor nature of the polyoxometalate ligand that may also facilitate alcohol dehydrogenation in the absence of base.
Copper‐Catalyzed One‐Pot Synthesis of Substituted Benzimidazoles
Authors: Jin Hongwei , Xu Xiaoliang , Gao Jianrong , Zhong Jianhua , Wang Yanguang
Published: February 2010

A copper‐catalyzed one‐pot synthesis of functionalized benzimidazoles has been developed. The procedure combines the copper‐catalyzed three‐component cascade reaction of sulfonyl azides, alkynes and 2‐bromoaniline and the copper‐catalyzed intramolecular N‐arylation of sulfonamides in one sequence, which afforded the products in moderate to good yields.
Synthesis of Sulfoximines and Sulfilimines with Aryl and Pyrazolylmethyl Substituents
Authors: Mancheño Olga García , Dallimore Jonathan , Plant Andrew , Bolm Carsten
Published: February 2010

Sulfoximines bearing pyrazolylmethyl and aryl substituents, which are relevant to the crop protection industry, and their corresponding sulfilimine intermediates, have been prepared from sulfide precursors by either iron‐catalyzed nitrogen transfer reactions or metal‐free imination procedures. Whereas the former approach leads to N‐nosyl‐substituted products, the latter affords N‐cyano derivatives.
Natural history and manifestations of the hypermobility type Ehlers–Danlos syndrome: A pilot study on 21 patients
Authors: Castori Marco , Camerota Filippo , Celletti Claudia , Danese Chiara , Santilli Valter , Saraceni Vincenzo Maria , Grammatico Paola
Published: February 2010

Hypermobility type Ehlers–Danlos syndrome (HT‐EDS) is a relatively frequent, although commonly misdiagnosed variant of Ehlers–Danlos syndrome, mainly characterized by marked joint instability and mild cutaneous involvement. Chronic pain, asthenia, and gastrointestinal and pelvic dysfunction are characteristic additional manifestations. We report on 21 HT‐EDS patients selected from a group of 40 subjects with suspected mild hereditary connective tissue disorder. General, mucocutaneous, musculoskeletal, cardiovascular, neurologic, gastrointestinal, urogynecological, and ear–nose–throat abnormalities are investigated systematically and tabulated. Six distinct clinical presentations of HT‐EDS are outlined, whose tabulation is a mnemonic for the practicing clinical geneticist in an attempt to diagnose this condition accurately. With detailed clinical records and phenotype comparison among patients of different ages, the natural history of the disorder is defined. Three phases (namely, hypermobility, pain, and stiffness) are delineated based on distinguishing manifestations. A constellation of additional, apparently uncommon abnormalities is also identified, including dolichocolon, dysphonia, and Arnold–Chiari type I malformation. Their further investigation may contribute to an understanding of the pathogenesis of the protean manifestations of HT‐EDS, and a more effective approach to the evaluation and management of affected individuals. © 2010 Wiley‐Liss, Inc.
Potocki–Shaffer syndrome: Comprehensive clinical assessment, review of the literature, and proposals for medical management
Authors: Swarr Daniel T. , Bloom Douglas , Lewis Richard Alan , Elenberg Ewa , Friedman Ellen M. , Glotzbach Caron , Wissman Scott D. , Shaffer Lisa G. , Potocki Lorraine
Published: February 2010

Potocki–Shaffer syndrome is a rare contiguous gene deletion syndrome due to haploinsufficiency of the 11p11.2p12 region and is characterized by craniofacial abnormalities, developmental delay, intellectual disability, multiple exostoses, and biparietal foramina. In this study, six patients with the Potocki–Shaffer syndrome were identified and evaluated using a multidisciplinary protocol that included assessments by a geneticist, ophthalmologist, otolaryngologist, orthopedist, nephrologist, audiologist, and neuropsychologist. Diagnostic studies included skeletal survey, magnetic resonance imaging of the brain, renal ultrasound, complete blood count, comprehensive metabolic panel, thyroid studies, and urinalysis. Using array comparative genomic hybridization, we further characterized the deletion in five of these patients. The results of these evaluations were combined with a comprehensive review of reported cases. Our data highlight the characteristic facial features, biparietal foramina, moderate‐to‐severe developmental delay and intellectual disability, myopia and strabismus, and multiple exostoses seen with this disorder. We also identify for the first time an association of Potocki–Shaffer syndrome with sensorineural hearing loss and autistic behaviors. Finally, we provide recommendations for the health maintenance of patients with Potocki–Shaffer syndrome. © 2010 Wiley‐Liss, Inc.
FOXE3 plays a significant role in autosomal recessive microphthalmia
Authors: Reis Linda M. , Tyler Rebecca C. , Schneider Adele , Bardakjian Tanya , Stoler Joan M. , Melancon Serge B. , Semina Elena V.
Published: February 2010

FOXE3 forkhead transcription factor is essential to lens development in vertebrates. The eyes of Foxe3/foxe3‐deficient mice and zebrafish fail to develop normally. In humans, autosomal dominant and recessive mutations in FOXE3 have been associated with variable phenotypes including anterior segment anomalies, cataract, and microphthalmia. We undertook sequencing of FOXE3 in 116 probands with a spectrum of ocular defects ranging from anterior segment dysgenesis and cataract to anophthalmia/microphthalmia. Recessive mutations in FOXE3 were found in four of 26 probands affected with bilateral microphthalmia (15% of all bilateral microphthalmia and 100% of consanguineous families with this phenotype). FOXE3‐positive microphthalmia was accompanied by aphakia and/or corneal defects; no other associated systemic anomalies were observed in FOXE3‐positive families. The previously reported c.720C > A (p.C240X) nonsense mutation was identified in two additional families in our sample and therefore appears to be recurrent, now reported in three independent microphthalmia families of varied ethnic backgrounds. Several missense variants were identified at varying frequencies in patient and control groups with some apparently being race‐specific, which underscores the importance of utilizing race/ethnicity‐matched control populations in evaluating the relevance of genetic screening results. In conclusion, FOXE3 mutations represent an important cause of nonsyndromic autosomal recessive bilateral microphthalmia. © 2010 Wiley‐Liss, Inc.
Enantioselective alkynylation of aldehydes catalyzed by a camphor sulfonylated amino alcohols titanium(IV) catalyst system
Authors: Gou Shaohua , Ye Zhongbin , Huang Zhiyu , Ma Xiping
Published: February 2010

A new titanium(IV) complex has been developed for the effective enantioselective alkynylation of phenylacetylene addition to aldehydes. The titanium(IV) complex was readily prepared in situ from (R)‐C‐(7,7‐dimethyl‐2‐oxo‐bicyclo[2.2.1]hept‐1‐yl)‐(1R,2S)‐N‐(2‐hydroxy‐1,2‐diphenyl‐ethyl)‐methanesulfonamide (1h) and tetraisopropyl titanate [Ti(i‐OPr)4]. A variety of aromatic aldehydes and α,β‐unsaturated aldehydes were found to be suitable substrates in the presence of the camphor sulfonylated amino alcohol titanium(IV) complex [10 mol% 1h, 40 mol% Ti(i‐OPr)4]. The desired propargylic alcohols were afforded with high isolated yields (up to 90%) and moderate enantioselectivities (up to 65% ee) under mild conditions. Copyright © 2010 John Wiley & Sons, Ltd.
Hans van Houwelingen and the Art of Summing up
Authors: Senn Stephen
Published: February 2010

Some personal remarks about Hans van Houwelingen's approach to biostatistics in general are followed by a discussion of his article with Koos Zwinderman and Theo Stijnen outlining a bivariate approach to meta‐analysis. It is concluded that this is more radical than many may realise in that it permits inter‐trial information to be recovered. This has some advantages but in theory opens the door to bias. It is concluded that in practice the size of this bias is likely to be small. I end with some further personal remarks to Hans.
Optimizing the outcome of surgery in patients with rectal cancer and synchronous liver metastases (Br J Surg 2010; 97: 383–390)
Authors: Beets G L
Published: February 2010

Liver first may be better
Sentinel lymph node biopsy in breast cancer guided by indocyanine green fluorescence (Br J Surg 2009; 96: 1289–1294)
Authors: Chiu C-C
Published: February 2010

The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses should be sent electronically via the BJS website (www.bjs.co.uk). All letters will be reviewed and, if approved, appear on the website. A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length.
A 93Nb Solid‐State NMR and Density Functional Theory Study of Four‐ and Six‐Coordinate Niobate Systems
Authors: Hanna John V. , Pike Kevin J. , Charpentier Thibault , Kemp Thomas F. , Smith Mark E. , Lucier Bryan E. G. , Schurko Robert W. , Cahill Lindsay S.
Published: February 2010

A variable B0 field static (broadline) NMR study of a large suite of niobate materials has enabled the elucidation of high‐precision measurement of 93Nb NMR interaction parameters such as the isotropic chemical shift (δiso), quadrupole coupling constant and asymmetry parameter (CQ and ηQ), chemical shift span/anisotropy and skew/asymmetry (Ω/Δδ and κ/ηδ) and Euler angles (α, β, γ) describing the relative orientation of the quadrupolar and chemical shift tensorial frames. These measurements have been augmented with ab initio DFT calculations by using WIEN2k and NMR‐CASTEP codes, which corroborate these reported values. Unlike previous assertions made about the inability to detect CSA (chemical shift anisotropy) contributions from NbV in most oxo environments, this study emphasises that a thorough variable B0 approach coupled with the VOCS (variable offset cumulative spectroscopy) technique for the acquisition of undistorted broad (−1/2↔+1/2) central transition resonances facilitates the unambiguous observation of both quadrupolar and CSA contributions within these 93Nb broadline data. These measurements reveal that the 93Nb electric field gradient tensor is a particularly sensitive measure of the immediate and extended environments of the NbV positions, with CQ values in the 0 to >80 MHz range being measured; similarly, the δiso (covering an approximately 250 ppm range) and Ω values (covering a 0 to approximately 800 ppm range) characteristic of these niobate systems are also sensitive to structural disposition. However, their systematic rationalisation in terms of the NbO bond angles and distances defining the immediate NbV oxo environment is complicated by longer‐range influences that usually involve other heavy elements comprising the structure. It has also been established in this study that the best computational method(s) of analysis for the 93Nb NMR interaction parameters generated here are the all‐electron WIEN2k and the gauge included projector augmented wave (GIPAW) NMR‐CASTEP DFT approaches, which account for the short‐ and long‐range symmetries, periodicities and interaction‐potential characteristics for all elements (and particularly the heavy elements) in comparison with Gaussian 03 methods, which focus on terminated portions of the total structure.
Biaryl Phosphite–Oxazoline Ligands from the Chiral Pool: Highly Efficient Modular Ligands for the Asymmetric Pd‐Catalyzed Heck Reaction
Authors: Mazuela Javier , Pàmies Oscar , Diéguez Montserrat
Published: February 2010

A highly modular library of readily available phosphite–oxazoline ligands L1–L21 a–g was successfully applied in the asymmetric Pd‐catalyzed Heck reactions of several substrates and triflates under thermal and microwave conditions. This ligand library contains three main ligand structures that have been designed by systematic modification of one of the most successful ligand families developed for this process. As well as studying the effect of these three ligand structures on the catalytic performance, we also evaluated the effect of modifying several ligand parameters in these ligand structures. The effectiveness of these ligands at transferring the chiral information into the product can be tuned by correctly choosing the ligand components. Both enantiomers of the Heck coupling products were obtained in excellent activities (conversion: >100 % in 10 min), regioselectivities (>99 %) and enantioselectivities (>99 % ee). Under microwave‐irradiation conditions, the reaction times were considerably shorter (full conversion was achieved in a few minutes) and the regio‐ and enantioselectivities were still excellent.
Studying the Origin of the Antiferromagnetic to Spin‐Canting Transition in the β‐p‐NCC6F4CNSSN.Molecular Magnet
Authors: Deumal Mercè , Rawson Jeremy M. , Goeta Andrés E. , Howard Judith A. K. , Copley Royston C. B. , Robb Michael A. , Novoa Juan J.
Published: February 2010

The crystal structure of the spin‐canted antiferromagnet β‐p‐NCC6F4CNSSN.at 12 K (reported in this work) was found to adopt the same orthorhombic space group as that previously determined at 160 K. The change in the magnetic properties of these two crystal structures has been rigorously studied by applying a first‐principlesbottom‐upprocedure above and below the magnetic transition temperature (36 K). Calculations of the magnetic exchange pathways on the 160 K structure reveal only one significant exchange coupling (J(d1)=−33.8 cm−1), which generates a three‐dimensional diamond‐like magnetic topology within the crystal. The computed magnetic susceptibility,χ(T), which was determined by using this magnetic topology, quantitatively reproduces the experimental features observed above 36 K. Owing to the anisotropic contraction of the crystal lattice, both the geometry of the intermolecular contacts at 12 K and the microscopicJABradical–radical magnetic interactions change: theJ(d1) radical–radical interaction becomes even more antiferromagnetic (−43.2 cm−1) and two additional ferromagnetic interactions appear (+7.6 and +7.3 cm−1). Consequently, the magnetic topologies of the 12 and 160 K structures differ: the 12 K magnetic topology exhibits two ferromagnetic sublattices that are antiferromagnetically coupled. Theχ(T) curve, computed below 36 K at the limit of zero magnetic field by using the 12 K magnetic topology, reproduces the shape of the residual magnetic susceptibility (having subtracted the contribution to the magnetization arising from spin canting). The evolution of these two ferromagneticJABcontributions explains the change in the slope of the residual magnetic susceptibility in the low‐temperature region.
Die Konfiguration bei Substitutionsreaktionen. Chirale Synthesen
Authors: Cuny Eckehard , Jaeger Rolf
Published: February 2010

An heutzutage anzuwendende pharmazeutische Produkte werden hohe Anforderungen gestellt, wenn sie physiologisch adaptabel sein sollen. Anhand der hier vorgestellten Synthesemethoden wird aufgezeigt, wie die notwendigen Enantiomerenreinheiten chemisch erreicht werden können. Die meisten dieser Reaktionen verlaufen nach einem SN2‐Mechanismus. Die Mechanismen des Isoharnstoff‐Verfahrens, der Mitsunobu‐Inversion und des Cäsium‐Effektes werden dargestellt bzw. erläutert. Die Verfahren werden vergleichend bewertet.
Schwermetalle in der Umwelt. Auf Ultra‐Spurensuche
Authors: Krachler Michael
Published: February 2010

Die vertrauensvolle Bestimmung von (Ultra‐)Spurenelementen in Umweltproben ist alles andere als trivial. Spurenelementanalysen extrem sauberer Umweltproben (Grundwasser, Schnee, Eis) erfordern ein Höchstmaß an Sauberkeit bei der Probennahme und ‐vorbereitung, die nachweis stärksten Analysenverfahren, sowie hochmotiviertes und erfahrenes Laborpersonal. Nur durch das perfekte Zusammenspiel aller dieser Komponenten können mithilfe moderner Analysenstrategien Fragen von gesellschaftspolitischer Relevanz erfolgreich beantwortet werden. Somit erlaubt z.B. der Blick zurück in die Vergangenheit – durch die Analyse alter Eisbohrkerne – die gegenwärtige Schwermetallbelastung der Umwelt in Perspektive zu setzen und zukünftige Entwicklungen besser einschätzen zu können. Leitungs‐ oder Mineralwasser? Was ist besser? Auch hier eröffnet die moderne Ultraspurenanalytik neue Perspektiven.
Medaillengewinne für Deutschland
Authors: Gehring Timo
Published: February 2010

250 Schüler aus 64 Ländern trafen sich im vergangenen Juli in Cambridge zur 41. Internationalen Chemie‐Olympiade (IChO). Die vierköpfige deutsche Schülermannschaft erzielte mit 1x Gold, 2x Silber und 1x Bronze ein hervorragendes Ergebnis.
Gangschaltung für die Speicherung solarer Energie
Authors: Walla Peter Jomo
Published: February 2010

Die meisten von uns Mitteleuropäern wissen: Bei höheren Sonneneinstrahlungen müssen wir uns vor Sonnenbrand schützen, sonst kann dies vor allem für die hellhäutigeren unter uns sehr unan genehme Folgen haben. Aber wussten Sie, dass auch Pflanzen sich unbedingt vor zu starker Sonnenstrahlung schützen müssen?
Scheduling time‐critical requests for multiple data objects in on‐demand broadcast
Authors: Lee Victor C. S. , Liu Kai
Published: February 2010

On‐demand broadcast is an effective data dissemination approach in mobile computing environments. Most of the recent studies on on‐demand data broadcast assume that clients request only a single‐data‐object at a time. This assumption may not be practical for the increasingly sophisticated mobile applications. In this paper, we investigate the scheduling problem of time‐critical requests for multiple data objects in on‐demand broadcast environments and observe that existing scheduling algorithms designed for single‐data‐object requests perform unsatisfactorily in this new setting. Based on our analysis, we propose new algorithms to improve the system performance. Copyright © 2010 John Wiley & Sons, Ltd.
Current Rectification in Temperature‐Responsive Single Nanopores
Authors: Guo Wei , Xia Hongwei , Xia Fan , Hou Xu , Cao Liuxuan , Wang Lin , Xue Jianming , Zhang Guangzhao , Song Yanlin , Zhu Daoben , Wang Yugang , Jiang Lei
Published: February 2010

Herein we demonstrate a fully abiotic smart single‐nanopore device that rectifies ionic current in response to the temperature. The temperature‐responsive nanopore ionic rectifier can be switched between a rectifying state below 34 °C and a non‐rectifying state above 38 °C actuated by the phase transition of the poly(N‐isopropylacrylamide) [PNIPAM] brushes. On the rectifying state, the rectifying efficiency can be enhanced by the dehydration of the attached PNIPAM brushes below the LCST. When the PNIPAM brushes have sufficiently collapsed, the nanopore switches to the non‐rectifying state. The concept of the temperature‐responsive current rectification in chemically‐modified nanopores paves a new way for controlling the preferential direction of the ion transport in nanofluidics by modulating the temperature, which has the potential to build novel nanomachines with smart fluidic communication functions for future lab‐on‐chip devices.
Organic Polyaromatic Hydrocarbons as Sensitizing Model Dyes for Semiconductor Nanoparticles
Authors: Zhang Yongyi , Galoppini Elena
Published: February 2010

The study of interfacial charge‐transfer processes (sensitization) of a dye bound to large‐bandgap nanostructured metal oxide semiconductors, including TiO2, ZnO, and SnO2, is continuing to attract interest in various areas of renewable energy, especially for the development of dye‐sensitized solar cells (DSSCs). The scope of this Review is to describe how selected model sensitizers prepared from organic polyaromatic hydrocarbons have been used over the past 15 years to elucidate, through a variety of techniques, fundamental aspects of heterogeneous charge transfer at the surface of a semiconductor. This Review does not focus on the most recent or efficient dyes, but rather on how model dyes prepared from aromatic hydrocarbons have been used, over time, in key fundamental studies of heterogeneous charge transfer. In particular, we describe model chromophores prepared from anthracene, pyrene, perylene, and azulene. As the level of complexity of the model dye‐bridge‐anchor group compounds has increased, the understanding of some aspects of very complex charge transfer events has improved. The knowledge acquired from the study of the described model dyes is of importance not only for DSSC development but also to other fields of science for which electronic processes at the molecule/semiconductor interface are relevant.
Understanding the role of asymmetric cell division in cancer using C. elegans
Authors: Hyenne Vincent , Chartier Nicolas T. , Labbé Jean‐Claude
Published: February 2010

Asymmetric cell division is an important process to generate cell diversity and maintain tissue homeostasis. Recent evidence suggests that this process may also be crucial to prevent tumor formation. In the past 30 years, the embryo of the nematode Caenorhabditis elegans has proven to be a very powerful model to study the molecular and cellular basis of asymmetric cell division. Understanding this process in Caenorhabditis elegans may thus lead to a better understanding of stem cell function and tumorigenesis in humans. Developmental Dynamics 239:1378–1387, 2010. © 2010 Wiley‐Liss, Inc.
Integration of diverse inputs in the regulation of Caenorhabditis elegans DAF‐16/FOXO
Authors: Landis Jessica N. , Murphy Coleen T.
Published: February 2010

In a remarkably conserved insulin signaling pathway that is well‐known for its regulation of longevity in worms, flies, and mammals, the major C. elegans effector of this pathway, DAF‐16/FOXO, also modulates many other physiological processes. This raises the question of how DAF‐16/FOXO chooses the correct targets to achieve the appropriate response in a particular context. Here, we review current knowledge of tissue‐specificity and interacting partners that modulate DAF‐16/FOXO functional output. Developmental Dynamics 239:1405–1412, 2010. © 2010 Wiley‐Liss, Inc.