bluuebunny/crossref_metadata_2025 huggingface dataset:
Bothrops moojeni snake venom-induced renal glomeruli changes in rat.
Authors: Boer-Lima PatrÃ­cia Aline , Gontijo JosÃ© Antonio Rocha , Cruz-HÃ¶fling Maria Alice
Published: May 2017

The venom of Bothrops moojeni has potent proteolytic and phospholipase A2 activities. In previous work, we showed that intravenous injection of this venom in rats decreased creatinine clearance and caused tubular dysfunction and histopathological changes with no alterations in blood pressure. The current study used scanning and transmission electron microscopy to assess the ultrastructural changes caused by B. moojeni venom (0.4 mg/kg i.v.) in rat renal glomeruli and correlated these alterations with the severity of proteinuria 5 hours, 16 hours, and 48 hours after venom injection. The changes included mesangiolysis, glomerular microaneurysms, and glomerular basement membrane (GBM) abnormalities. In addition, there was a reduction in the number and width of podocyte pedicels, which caused a reduction in the number of filtration slits. Electron-dense amorphous material, which may be proteinaceous in origin, was found in the pedicels. The severity of the ultrastructural abnormalities correlated with the level of proteinuria. These morphophysiological changes were attributed to biochemical and physiological disturbances in the components of the GBM and mesangial matrix as well as in cytoskeleton-associated proteins of podocytic processes, and could account for the breakdown of optimal glomerular filtration barrier functioning. These results, together with the absence of appreciable glomerular fibrin deposits, support the hypothesis of a direct activity of B. moojeni venom on rat kidneys. Proteolytic activity of the venom on renal glomeruli could then contribute to the onset of acute renal failure, and would explain the clinical manifestations of renal injury after bites by this and other Bothrops species.
Cerebral involvement in benign tertian malaria.
Authors: Beg M A , Khan R , Baig S M , Gulzar Z , Hussain R , Smego R A
Published: May 2017

Although Plasmodium vivax usually causes benign uncomplicated malaria, it can occasionally result in severe disease with life-threatening, end-organ involvement generally seen with falciparum malaria. We report a case of cerebral malaria caused by P. vivax and review the literature on this subject.
Roof gutters: a key container for Aedes aegypti and Ochlerotatus notoscriptus (Diptera: Culicidae) in Australia.
Authors: Montgomery Brian L , Ritchie Scott A
Published: May 2017

The contribution of roof gutters to Aedes aegypti (L.) and Ochlerotatus notoscriptus (Skuse) pupal populations was quantified for the first time in Cairns, Australia. Concurrent yard and roof surveys yielded an estimated 6,934 mosquito pupae, comprising four species. Roof gutters were an uncommon but productive source of Ae. aegypti in both wet season (n = 11) and dry season (n = 2) surveys, producing 52.6% and 39.5% of the respective populations. First story gutters accounted for 92.3% of the positive gutters. Therefore, treatment of roof gutters is a critical element in Ae. aegypti control campaigns during dengue outbreaks. In wet season yards, the largest standing crops of Ae. aegypti occurred in garden accoutrements, discarded household items, and rubbish (36.4%, 28.0%, and 20.6%, respectively). In dry season yards, rubbish produced 79.6% of the Ae. aegypti pupae. The number of Ae. aegypti pupae/person was 2.36 and 0.59 for the wet and dry season surveys, respectively.
Dengue and its vectors in Thailand: introduction to the study and seasonal distribution of Aedes larvae.
Authors: Strickman Daniel , Kittayapong Pattamaporn
Published: May 2017

A study was conducted from 1989 to 1994 that included surveillance for dengue and its mosquito vectors in 3 villages and 2 schools in Chachoengsao Province, 100 km east of Bangkok, Thailand. The study is introduced, and results of larval surveys for Aedes mosquitoes (predominantly Aedes aegypti (L.)), with 94, 86, and 90% of positive containers infested by this species in the hot, wet, and cool seasons, respectively), are described. These surveys were conducted in 1990-1991 during each of the 3 principal seasons: hot (February-April), rainy (May-October), and cool (November-January). Indoor maximum and minimum temperatures were consistently greater than outdoor temperatures. The differences between maximum and minimum temperatures both indoors and outdoors varied seasonally, with the greatest differences in the cool season and the least differences in the rainy season. The most rain fell in September and October and the least rain in December, January, and February. The number of Aedes larvae in each container was categorized (no larvae, 1-9 larvae, 10-50 larvae, > 50 larvae) by dipping with a fishnet or by visual examination (for drinking water). A larval index was calculated for each house and school by summing the estimations from each container. These indexes showed that one village had more larvae in every season (mean larval index per house = 117) than the other 2 villages (larval indexes of 86 and 70). The larval index of each house was mapped for each season, and the distribution was spatially analyzed by producing kriged estimates of interpolated data. These analyses showed that larvae were significantly concentrated in particular areas of the villages, especially during the wet season. Even when larvae were least abundant, every part of each village had at least some larvae. The results of the study imply that dengue vector control programs in Southeast Asian villages could increase their efficiency by applying their most energetic efforts on schools and areas with the greatest abundance of larvae, as measured by calculation of larval indexes.
Treatment of children with Plasmodium falciparum malaria with chloroquine in Guinea-Bissau.
Authors: Kofoed Poul-Erik , Lopez Francisco , Johansson Peter , SandstrÃ¶m Anita , Hedegaard Kathryn , Aaby Peter , Rombo Lars
Published: May 2017

Children with symptomatic malaria in Bissau, Guinea-Bissau were randomly assigned to treatment with a 25 mg/kg total dose of chloroquine as recommended by the National Malaria Program or with a higher total dose of 50 mg/kg. Sixty-seven and 62 children, respectively, completed the treatment and were then followed once a week for five weeks. Treatment with a dose of 50 mg/kg was significantly more effective than treatment with 25 mg/kg in preventing recrudescence. The cumulative relative risk (95% confidence interval) of having parasitemia in the low-dose group during follow-up was 0.20 (0.08-0.52) on day 21, 0.38 (0.17-0.86) on day 28, and 0.48 (0.23-0.98) on day 35. Few adverse events were reported, although more children complained of vomiting and diarrhea on day 2 in the high-dose group compared with those in the low-dose group. However, this difference was not statistically significant. We conclude that a dose of 50 mg/kg of chloroquine could be recommended for treatment of Plasmodium falciparum malaria in Bissau. To minimize the risk of side effects, this higher dose should be given divided into two daily doses over a three-day period.
Novel primer sequences for polymerase chain reaction-based detection of Trypanosoma brucei gambiense.
Authors: Radwanska Magdalena , Claes Filip , Magez Stefan , Magnus Eddy , Perez-Morga David , Pays Etienne , Büscher Philippe
Published: May 2017

Progress in diagnosis, treatment, and epidemiology of human African trypanosomiasis (sleeping sickness) depends on the existence of specific and sensitive diagnostic tools. Inherent shortcomings of serologic and parasitologic diagnostic methods can be overcome by molecular techniques. Therefore, we have developed a new polymerase chain reaction (PCR) test using primers derived from the recently identified sequence of the Trypanosoma brucei gambiense-specific glycoprotein (TgsGP). The specificity of the TgsGP-PCR was evaluated on DNA extracted from 73 different trypanosome populations belonging to diverse taxonomic groups that were isolated from various host species, and from different geographic origins. The TgsG-PCR was shown to be specific for T. b. gambiense and was suitable for detection of trypanosome DNA in blood samples of patients with confirmed sleeping sickness.
Enterocytozoon bieneusi among children with diarrhea attending Mulago Hospital in Uganda.
Authors: Tumwine James K , Kekitiinwa Addy , Nabukeera Nicolette , Akiyoshi Donna E , Buckholt Michael A , Tzipori Saul
Published: May 2017

The prevalence of Enterocytozoon bieneusi in the general population is unknown. Using genetic tools, we investigated its prevalence and contribution to diarrhea and malnutrition in hospitalized children in Uganda. A cross-sectional, case-control study involving diarrheic children who were matched for age and sex (3:1) with control children. Measurements included anthropometry and clinical assessment. A total of 17.4% of 1,779 children with diarrhea were infected with E. bieneusi compared with 16.8% of 667 control children (CHI2 = 0.137, P = 0.712). Prevalence was highest during the rainy seasons. There was no significant relationship between infection with E. bieneusi and stunting, being underweight, wasting, or acute diarrhea. However, children who were E. bieneusi-positive by a polymerase chain reaction (PCR) had diarrhea for a longer period (15.15 versus 9.67 days; F = 12.02; P = 0.001) compared with children who were either uninfected or were E. bieneusi-positive by a nested PCR. We conclude that E. bieneusi is widespread among children 3-36 months of age in Uganda, and that in a cross-sectional study, there was no clear association of E. bieneusi with poor nutrition or diarrhea. Since E. bieneusi is closely linked with persistent diarrhea and wasting in adults who are positive for human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), the outcome of follow-up studies involving children who are HIV/AIDS-positive and severely malnourished children may be entirely different and warrants further study.
Comparison of autofluorescence and iodine staining for detection of Isospora belli in feces.
Authors: Bialek Ralf , Binder Nicole , Dietz Klaus , Knobloch Jürgen , Zelck Ulrike E
Published: May 2017

To evaluate the sensitivity of autofluorescence for detection of Isospora oocysts, wet preparations of 192 stool samples from patients with chronic diarrhea were examined by fluorescence microscopy and by light microscopy after iodine staining used for routine screening for ova and parasites. Silicon-chambered glass coverslips were used for fluorescence microscopy. Isospora oocysts were detected in 46 iodine-stained concentrated stool samples; 91 samples were positive by autofluorescence. According to the maximum likelihood estimates, examination by fluorescence (95.7%; 95% confidence interval [CI], 85.2-99.5) was significantly more sensitive than iodine staining (48.4%; 95% CI, 37.7-59.1). Examination for autofluorescence is a simple, highly sensitive, inexpensive, and easily applicable method to detect Isospora spp. oocysts in feces.
Molecular characterization of California serogroup viruses isolated in Russia.
Authors: Vanlandingham D L , Davis B S , Lvov D K , Samokhvalov E i , Lvov S D , Black W C , Higgs S , Beaty B J
Published: May 2017

Nucleotide sequencing was used to characterize unidentified California (CAL) serogroup virus isolates from Russia. These viruses were isolated from mosquitoes and humans during epidemiologic investigations on the role of CAL serogroup viruses in the increased incidence of arboviral encephalitis in Russia. Most of the isolates were identified serologically as snowshoe hare (SSH), Inkoo (INK), and Tahyna (TAH) viruses, but some of the isolates were difficult to classify serologically, suggesting that they could be reassortant viruses. There is evidence that at least 2 of these viruses are not reassortant viruses. Sequence analysis revealed that the Russian viruses differ from other Eurasian and North American CAL serogroup viruses in all of the segments analyzed. They are most closely related to SSH virus. Whether they differ sufficiently to be considered a new group of SSH-like viruses remains to be determined.
Epizootic activity of Murray Valley encephalitis virus in an aboriginal community in the southeast Kimberley region of Western Australia: results of cross-sectional and longitudinal serologic studies.
Authors: Broom Annette K , Lindsay Michael D A , Plant Aileen J , Wright Anthony E , Condon Robert J , Mackenzie John S
Published: May 2017

Murray Valley encephalitis (MVE) virus is a mosquito-borne flavivirus causing severe encephalitis with a resultant high morbidity and mortality. In the period 1989-1993, we undertook a cross-sectional and longitudinal study by annually screening members of a small remote Aboriginal community in northwestern Australia for MVE virus antibodies. Of the estimated 250-300 people in the community, 249 were tested, and 52.6% had positive serology to MVE. The proportion testing positive increased with increasing age group, and males were slightly more likely to be positive than females. During the study period, a high proportion of the population seroconverted to MVE; the clinical/subclinical ratio seems to be lower than previously reported. Although MVE is mostly asymptomatic, the devastating consequences of clinical illness indicate that advice should be provided regarding the avoidance of mosquito bites. Our longitudinal study showed that the risk of seroconversion was similar for each age group, not just the young.
The sensitivity and specificity of Leishmania chagasi recombinant K39 antigen in the diagnosis of American visceral leishmaniasis and in differentiating active from subclinical infection.
Authors: Braz Regina F S , Nascimento Eliana T , Martins Daniella R A , Wilson Mary E , Pearson Richard D , Reed Steven G , Jeronimo Selma M B
Published: May 2017

The sensitivity and specificity of a Leishmania chagasi recombinant K39 (rK39)-based enzyme-linked immunosorbent assay (ELISA) for visceral leishmaniasis (VL) was assessed in Natal, Brazil. Anti-rK39 antibodies were detected in 93.3% of patients with parasitologically confirmed VL (n = 120) and in 33 others with clinically diagnosed disease. Anti-rK39 antibodies decreased significantly following treatment. The presence of antibodies was inversely correlated with development of a positive leishmanin skin test result. Anti-rK39 antibodies were detected in only 2.9% of asymptomatic subjects with a positive skin test result (n = 168). They were not detected in healthy controls (n = 30) or in persons with Chagas' disease (n = 13) or active tuberculosis (n = 31). Antibodies were found in only one of 13 patients with cutaneous leishmaniasis. In contrast, an ELISA using total L. chagasi promastigote antigen was sensitive, but not specific. The results indicate that the rK39-based ELISA is a sensitive and specific diagnostic test for symptomatic VL and can differentiate progressive from self-resolving infection.
Molecular epidemiology of malaria in Cameroon. XIII. Analysis of pfcrt mutations and in vitro chloroquine resistance.
Authors: Basco Leonardo K
Published: May 2017

The key Lys76Thr amino-acid substitution in Plasmodium falciparum chloroquine-resistance transporter (PfCRT) has been shown to be a reliable marker associated with chloroquine-resistant phenotype in reference clones, but few discordant results have been observed in field isolates. To further examine the relationship between in vitro chloroquine response and pfcrt alleles, the entire exon 2 of the pfcrt gene of 157 Cameroonian isolates was sequenced. All isolates were characterized as having either Cys-72, Met-74, Asn-75, and Lys-76 (wild-type alleles), Cys-72, Ile-74, Glu-75, and Thr-76 (mutant alleles), or mixed alleles. The hypothetical threshold 50% inhibitory concentration (IC50) set at 100 nM distinguished between isolates carrying the wild-type alleles and those with mutant alleles in a large majority of cases (135 of 139 isolates with unmixed pfcrt alleles). Isolates presenting discordant results generally had IC50s within an intermediate range. In vitro chloroquine response of isolates with mixed pfcrt alleles was highly variable. Although discordant results between chloroquine-resistant phenotype and pfcrt alleles were not explained by the immediate adjacent codons, the key Lys76Thr codon may prove to be a highly reliable genetic marker for the epidemiologic monitoring of chloroquine resistance by means of molecular techniques.
In vitro activity of tafenoquine alone and in combination with artemisinin against Plasmodium falciparum.
Authors: Ramharter Michael , Noedl Harald , Thimasarn Krongthong , Wiedermann Gerhard , Wernsdorfer Gunther , Wernsdorfer Walther H
Published: May 2017

Emergence and spread of drug-resistant falciparum malaria has created an urgent demand for alternative therapeutic agents. This study was conducted to assess the in vitro blood schizontocidal activity of tafenoquine, the most advanced candidate drug of the 8-aminoquinolines, and of its 1:1 combination with artemisinin in fresh isolates of Plasmodium falciparum in an area with multi-drug resistance, measuring the inhibition of schizont maturation. In 43 successfully tested parasite isolates, the mean effective concentrations (ECs) of tafenoquine were 209 nmol/L for the EC50, and 1,414 nmol/L for the EC90. Tafenoquine showed no significant activity relationships with mefloquine, artemisinin, and chloroquine. With quinine, a highly significant activity relationship was observed at the EC50, but not at the EC90. The EC50, and EC90 of the tafenoquine-artemisinin combination were 15.9 nmol/L and 84.3 nmol/L. The combination was synergistic. Tafenoquine appears to be a promising candidate for treating multidrug-resistant falciparum malaria, especially in combination with artemisinin derivatives.
Genetics of drug-resistant Plasmodium falciparum malaria in the Venezuelan state of Bolivar.
Authors: Contreras Carmen E , Cortese Joseph F , Caraballo Alejandro , Plowe Christopher V
Published: May 2017

The state of Bolivar in Venezuela experiences episodic outbreaks of multidrug-resistant Plasmodium falciparum malaria. We obtained P. falciparum-infected blood samples in Bolivar in 1998-2000, and performed molecular assays for mutations conferring resistance to the antifolate combination of sulfadoxine-pyrimethamine (SP) and to chloroquine. All infections carried the dihydrofolate reductase (dhfr) S108A and N51I mutations, and 45% of the infections had the dhfr C50R mutation, which has been implicated in mid-level resistance to SP. Two dihydropteroate synthase (dhps) mutations also involved in SP resistance, A581G and K540E, were detected in 90% and 67% of the samples, respectively. The dhfr 1164L mutation, which confers high-level resistance, was not identified. The P. falciparum chloroquine resistance transporter (pfcrt) K76T mutation, which is critical for chloroquine resistance, was found in 167 of 168 infections. Six dhfr/dhps allelotypes and four pfcrt-resistant alleles were observed. Their interrelationships suggest a semi-clonal propagation of P. falciparum malaria in Bolivar, and an invasion of multi-resistant pathogens from Brazil. Despite national restrictions on the use of SP and chloroquine, genotypic resistance to these therapies remains widespread in Bolivar.
Malaria and human immunodeficiency virus infection as risk factors for anemia in infants in Kisumu, western Kenya.
Authors: van Eijk Anna M , Ayisi John G , Ter Kuile Feiko O , Misore Ambrose O , Otieno Juliana A , Kolczak Margarette S , Kager Piet A , Steketee Richard W , Nahlen Bernard L
Published: May 2017

The role of maternal and pediatric infection with human immunodeficiency virus type 1 (HIV-1) and malaria as risk factors for anemia was determined in a birth cohort of infants born to mothers participating in a study of the interaction between placental malaria and HIV infection, in Kisumu, Kenya. Between June 1996 and April 2000, 661 infants born to 467 HIV-seropositive and 194 HIV-seronegative mothers were monitored monthly from birth. At each visit a questionnaire was completed and a blood sample was collected for the determination of hemoglobin levels and detection of malaria and HIV. Anemia was common and increased from 13.6% at one month to 75% at six months and remained high throughout the second half of infancy. Placental malaria, infant malaria, and HIV infection of the infant were all associated with infant anemia in a multivariate model, adjusting for other co-variates found to be associated with infant anemia. The HIV-infected infants with malaria parasitemia had lower mean hemoglobin levels compared with HIV-uninfected infants, or HIV-infected infants without malaria, suggesting that HIV-infected infants are particularly vulnerable to the adverse consequences of malaria at this age. Early detection and prompt treatment of infant malaria and treatment of anemia as part of the study protocol failed to prevent most of the infants from becoming anemic. Although not proven effective in this study, micronutrient supplementation should be prospectively assessed in HIV-infected infants as a means of preventing anemia.
Onchodermal skin disease in a hyperendemic onchocerciasis focus in western Uganda.
Authors: Kipp Walter , Bamhuhiiga Jotham
Published: May 2017

To assess the degree of skin disease in Simulium neavei s.s.-transmitted onchocerciasis, 72 patients infected with Onchocerca volvulus in the Kabarole district of Uganda were studied. They were clinically and parasitologically evaluated. Onchocercal skin lesions were determined using a modified Murdoch skin assessment, and skin scores were calculated. The chronic skin score (4.0) was associated with age, and the acute skin score (8.5) was significantly higher in males. The burden of onchocercal skin lesions was found to be high in most patients. The number of nodules (median number 1.9) and the microfilarial load (geometric mean of microfilaria 11.5) were not determinants for the burden of onchocercal skin disease in infected individuals. The study concludes that onchodermatitis is a serious medical condition in Kigoyera Parish and needs to be considered in all efforts to control onchocerciasis.
Ecologic niche modeling and differentiation of populations of Triatoma brasiliensis neiva, 1911, the most important Chagas' disease vector in northeastern Brazil (hemiptera, reduviidae, triatominae).
Authors: Costa Jane , Peterson A Townsend , Beard C Ben
Published: May 2017

Ecologic niche modeling has allowed numerous advances in understanding the geographic ecology of species, including distributional predictions, distributional change and invasion, and assessment of ecologic differences. We used this tool to characterize ecologic differentiation of Triatoma brasiliensis populations, the most important Chagas' disease vector in northeastern Brazil. The species' ecologic niche was modeled based on data from the FundaÃ§Ã£o Nacional de SaÃºde of Brazil (1997-1999) with the Genetic Algorithm for Rule-Set Prediction (GARP). This method involves a machine-learning approach to detecting associations between occurrence points and ecologic characteristics of regions. Four independent "ecologic niche models" were developed and used to test for ecologic differences among T. brasiliensis populations. These models confirmed four ecologically distinct and differentiated populations, and allowed characterization of dimensions of niche differentiation. Patterns of ecologic similarity matched patterns of molecular differentiation, suggesting that T. brasiliensis is a complex of distinct populations at various points in the process of speciation.
Hepatic hydatid cysts with superinfection in a non-endemic area in Taiwan.
Authors: Chen Yi-Cheng , Yeh Ta-Sen , Tseng Jeng-Hwei , Huang Shiu-Feng , Lin Deng-Yn
Published: May 2017

Hepatic hydatid cysts are extremely rare in Taiwan. We report a case of complicated, multivesicular, hydatid cysts in the liver and a secondary infection with Klebsiella pneumoniae. The cysts were detected in an early stage by ultrasonography and computed tomography and treated successfully with radical resection.
Short report: Failure of the OptiMAL rapid malaria test as a tool for the detection of asymptomatic malaria in an area of Thailand endemic for Plasmodium falciparum and P. vivax.
Authors: Coleman Russell E , Maneechai Nongnuj , Ponlawat Alongkot , Kumpitak Chalermpon , Rachapaew Nattawan , Miller Robert S , Sattabongkot Jetsumon
Published: May 2017

We evaluated the efficacy of the OptiMAL assay in a cross-sectional malaria survey in western Thailand from April to August 2001. Expert microscopy of Giemsa-stained thick and thin blood films was used as the gold standard. Positive control lines were evident in 99% (1,128 of 1,137) of the assays tested. However, 34% (384 of 1,128) of assays produced an aberrant result (a positive P. falciparum-specific line and a negative panmalarial line). False-positive panmalarial and Plasmodium falciparum-specific lines occurred in 25.9% (270 of 1,042) and 60.3% (628 of 1,042) of microscopy-negative samples, respectively. Due to the preponderance of false-positive test results, it was necessary to develop subjective criteria for test positivity based on line intensity. For determination of assay performance during this study, we therefore considered all test lines that were scored as intermediate or strong as positive and lines that were faint as negative. Using these criteria, we determined that the sensitivity of the OptiMAL assay for P. falciparum was 25% with > 500 parasites/microl and 10.5% with > 100 parasites/microl, while for P. vivax, the sensitivity at the same parasite rates was 100% and 41.7%, respectively. Further studies are required to determine whether the problems we identified are limited to this particular lot of OptiMAL assays.
The role of agricultural use of insecticides in resistance to pyrethroids in Anopheles gambiae s.l. in Burkina Faso.
Authors: Diabate Abdoulaye , Baldet Thierry , Chandre Fabrice , Akoobeto Martin , Guiguemde T Robert , Darriet FrÃ©dÃ©ric , Brengues CÃ©cile , Guillet Pierre , Hemingway Janet , Small Graham J , Hougard Jean Marc
Published: May 2017

Agricultural use of insecticides is involved in the selection of resistance to these compounds in field populations of mosquitoes in Burkina Faso. Anopheles gambiae s.l. was resistant to permethrin and DDT in cotton-growing and urban areas, but susceptible in areas with limited insecticide selection pressure (rice fields and control areas). Nevertheless, resistance to these insecticides was observed in a village on the outskirts of the rice fields at the end of the rainy season, suggesting that the latter population of mosquitoes had migrated from the surrounding cotton villages into the rice fields. A seasonal variation of resistance observed in the cotton-growing area is related to the distribution of the molecular M and S forms of An. gambiae, since resistance to pyrethroids has so far only been reported in the S form. Pyrethroid resistance in west African An. gambiae was conferred by target site insensitivity through a knockdown resistance (kdr)-like mutation, which was present at high frequencies in mosquitoes in the cotton-growing and urban areas.
Climatic and demographic determinants of American visceral leishmaniasis in northeastern Brazil using remote sensing technology for environmental categorization of rain and region influences on leishmaniasis.
Authors: Thompson R Alex , Wellington de Oliveira Lima JosÃ© , Maguire James H , Braud Dewitt H , Scholl Daniel T
Published: May 2017

Remote sensing (RS) permits evaluation of spatial and temporal variables that can be used for vector-borne disease models. A Landsat Thematic Mapper scene covering CanindÃ©, CearÃ¡ in northeastern Brazil (September 25, 1986) was spectrally enhanced and classified using ERDAS (Atlanta, GA) Imagine for 873 4-km2 areas. The population and number of cases of American visceral leishmaniasis (AVL) were determined for each 4-km2 area. Relative risk (RR) ratios were calculated for climate, demographic, and case data recorded for 17 years by the Municipality of ConidÃ©. The RR of AVL for a child less than 10 years old from the foothills relative to non-foothill residency was 4.0 (95% confidence limit = 3.5, 4.5). The RR of AVL in children was 9.1 during a time when the three-year rolling rain average (current year plus two previous year's precipitation) was between 40 and 60 cm relative to rain greater than 100 cm. The results suggest that features detected by RS techniques combined with climatic variables can be used to determine the risk of AVL in northeastern Brazil.
Intraobserver and interobserver variation of ultrasound diagnosis of Oesophagostomum bifurcum colon lesions.
Authors: Storey P A , Spannbrucker N , Agongo E A , van Lieshout L , Zeim J P , Magnussen P , Polderman A M , Doehring E
Published: May 2017

Infection by the nematode Oesophagostomum bifurcum is focally distributed in Africa and causes a syndrome of abdominal pain, obstruction, or abdominal mass because of its predilection for invasion of colonic mucosa. To determine the reliability of ultrasound for the detection of colon pathology induced by this parasite, three studies to assess the intraobserver and interobserver variation of the technique were performed. In an area of northern Ghana endemic for O. bifurcum, 181 people from a low-prevalence village and 62 people from a high-prevalence village were examined twice by the same observer, and 111 people were independently examined by two observers in a moderately endemic village. The kappa statistics for the prevalence observations in the three studies were 0.82, 0.87, and 0.81, respectively, and kappa values for the intensity observations were 0.66, 0.63, and 0.71, respectively. The upper 95% confidence intervals of the average absolute difference in nodule size measurements in Study 1 and Study 3 were 3.6 and 4.5 mm, respectively. Therefore, ultrasound is useful in the diagnosis and management of O. bifurcum colon infection.
TRANSMISSION OF EPIDEMIC DENGUE HEMORRHAGIC FEVER IN EASTERNMOST INDONESIA
Authors: SUKRI NONO C. , LARAS KANTI , WANDRA TONI , DIDI SUKMAN , LARASATI RIA P. , RACHDYATMAKA JOSEF R. , OSOK STEVIE , TJIA PETRUS , SARAGIH JOHN M. , HARTATI SRI , LISTYANINGSIH ERLIN , PORTER KEVIN R. , BECKETT CHARMAGNE G. , PRAWIRA INGERANI S. , PUNJABI NARAIN , SUPARMANTO SRI A. , BEECHAM H. JAMES , BANGS MICHAEL J. , CORWIN ANDREW L.
Published: May 2017

In April 2001, a second suspected outbreak of dengue hemorrhagic fever in the easternmost region of Indonesia was investigated in Merauke, a town located in the southeastern corner of Papua, by the Indonesian Ministry of Health and the U.S. Naval Medical Research Unit No. 2. Principal case criteria of hemorrhagic disease provided for a study enrollment of 15 clinically acute and 37 convalescing subjects. Additionally, 32 comparable age/sex controls were selected from neighboring households. Laboratory diagnosis involved three testing methodologies: virus isolation by cell culture, a reverse transcriptase–polymerase chain reaction (RT-PCR) assay, and serologic assays. Antibody (IgM) to dengue virus was detected in 27% of the acute clinical cases, 30% of the convalescing cases, and only 3% of the matched controls. Dengue 3 was the only viral serotype detected from acute serum samples by the RT-PCR. The mean ± SD age of the acute and convalescing cases was 7.8 ± 5.4 years. Overall hospital records accounted for 172 suspected outbreak cases, all urban residents of Merauke with no recent travel history outside the area. The estimated outbreak-associated case fatality rate among all suspected dengue cases was 1.2%. A seven-year retrospective review of hospital records in Merauke showed negligible disease reporting involving hemorrhagic disease prior to the outbreak.
PREVALENCE OF ANAPLASMA PHAGOCYTOPHILA AND BORRELIA BURGDORFERI IN IXODES PERSULCATUS TICKS FROM NORTHEASTERN CHINA
Authors: CAO WU-CHUN , ZHAO QIU-MIN , ZHANG PAN-HE , YANG HONG , WU XIAO-MING , WEN BO-HAI , ZHANG XI-TAN , HABBEMA J. DIK F.
Published: May 2017

A total of 1,345 Ixodes persulcatus ticks collected from northeastern China were investigated for the presence of Anaplasma phagocytophila and Borrelia burgdorferi by a nested polymerase chain reaction (PCR). Sixty-two (4.6%) ticks were positive for A. phagocytophila and 454 (33.8%) were positive for B. burgdorferi. Seven (0.5%) were coinfected with both agents. Sequence analysis of 919-basepair PCR amplicons revealed three types of A. phagocytophila. Type 1 was identical to the published sequences of A. phagocytophilas responsible for human granulocytic ehrlichiosis (HGE). The other two variants differed from the HGE agent sequence at one and four positions, respectively. These findings imply that infection with A. phagocytophila poses a potential health threat to both humans and animals in northeastern China, and that ehrlichiosis should be considered in the differential diagnosis of febrile patients with a history of tick bite, particularly when clinical manifestations are atypical for Lyme disease.
SPOTTED FEVER GROUP RICKETTSIAE IN TICKS FROM THE MASAI MARA REGION OF KENYA
Authors: MACALUSO KEVIN R. , DAVIS JON , ALAM UZMA , KORMAN AMY , RUTHERFORD JEREMIAH S. , ROSENBERG RONALD , AZAD ABDU F.
Published: May 2017

We have identified for the first time Rickettsia africae, and the ticks that harbored them, in Kenya. A total of 5,325 ticks were collected from vegetation, livestock, and wild animals during two field trips to southwestern Kenya. Most were immature forms (85.2%) belonging to the genera Amblyomma or Rhipicephalus. The adults also included representatives from the genus Boophilus. Ticks were assessed for rickettsial DNA by a polymerase chain reaction (PCR) using primers for the spotted fever group (SFG)–specific rickettsial outer membrane protein A (rompA) gene, and positive amplicons were sequenced. While none of the immature ticks tested positive by PCR, 15.8% of the adult Amblyomma variegatum and less than 1% of the Rhipicephalus spp. were SFG positive. Sequences of amplified products were identified as R. africae. These findings extend the known range of R. africae.
SHORT REPORT: A NEW CASE REPORT OF HUMAN MESOCESTOIDES INFECTION IN THE UNITED STATES
Authors: FUENTES MÀRIUS V. , GALÁN-PUCHADES M. TERESA , MALONE JOHN B.
Published: May 2017

The twenty-seventh documented case of human Mesocestoides infection, which corresponds to the seventh documented case in the United States, is reported. The case had its origin in Alexandria, Louisiana in the summer of 1998. The patient was a 19-month-old boy. The strobila consisted of 35 proglottids that included mature as well as gravid segments containing a ventral genital pore and a parauterine organ. After a detailed microscopic examination, the tapeworm was identified as belonging to the genus Mesocestoides. Mesocestoides variabilis is the probable species responsible for the infection, since the six cases previously reported in the United States were identified as this species. After the treatment with a single dose of praziquantel (10 mg/kg), the tapeworm segments were no longer detectable in the child’s feces. A food-borne origin of this infection derived from culinary customs of the Acadian and Creole communities in Louisiana is proposed.
DIHYDROFOLATE REDUCTASE AND DIHYDROPTEROATE SYNTHASE GENOTYPES ASSOCIATED WITH IN VITRO RESISTANCE OF PLASMODIUM FALCIPARUM TO PYRIMETHAMINE, TRIMETHOPRIM, SULFADOXINE, AND SULFAMETHOXAZOLE
Authors: KHALIL INSAF , RØNN ANITA M. , ALIFRANGIS MICHAEL , GABAR HAYTHAM A. , SATTI GWIRIA M. H. , BYGBJERG IB C.
Published: May 2017

A total of 70 Plasmodium falciparum isolates were tested in vitro against pyrimethamine (PYR), tri-methoprim (TRM), sulfadoxine (SDX), and sulfamethoxazole (SMX), and their dihydrofolate reductase (dhfr) and dihydropteroate synthase (dhps) genotypes were determined. dhfr genotypes correlated with PYR and TRM drug responses (r = 0.93 and 0.85). Isolates with wild-type alleles showed mean half inhibitory concentrations (IC50 ± SD) of 0.10 ± 0.10 and 0.15 ± 0.06 μg/100 μl for PYR and TRM. Parasites with mutations at codons 108 and 51 alone or combined with codon 59 have IC50 of 11.46 ± 0.86 (PYR) and 2.90 ± 0.59 μg/100 μl (TRM). For both drugs, the differences in the mean IC50 between wild and mutant parasites were statistically significant (P < 0.001). Isolates with mixed wild and mutant alleles showed an intermediate level of susceptibility. Our data show partial cross-resistance between PYR/TRM and SDX/SMX (r = 0.85 and 0.65). Correlation was not observed between different dhps genotypes and the in vitro outcome to SDX and SMX (r = 0.30 and 0.34). The lack of correlation could be due to folates and para-aminobenzoic acid in the RPMI medium and the serum used to supplement the cultures.
PHASE 1 STUDIES OF WALTER REED ARMY INSTITUTE OF RESEARCH CANDIDATE ATTENUATED DENGUE VACCINES: SELECTION OF SAFE AND IMMUNOGENIC MONOVALENT VACCINES
Authors: KANESA-THASAN N. , EDELMAN R. , TACKET C. O. , WASSERMAN S. S. , VAUGHN D.W. , COSTER T. S. , KIM-AHN G. J. , DUBOIS D. R. , PUTNAK J. R. , KING A. , SUMMERS P. L. , INNIS B. L. , ECKELS K. H. , HOKE C. H.
Published: May 2017

We describe the results of initial safety testing of 10 live-attenuated dengue virus (DENV) vaccine candidates modified by serial passage in primary dog kidney (PDK) cells at the Walter Reed Army Institute of Research. The Phase 1 studies, conducted in 65 volunteers, were designed to select an attenuated vaccine candidate for each DENV serotype. No recipient of the DENV candidate vaccines sustained serious injury or required treatment. Three vaccine candidates were associated with transient idiosyncratic reactions in one volunteer each, resulting in their withdrawal from further clinical development. Increasing PDK cell passage of DENV-1, DENV-2, and DENV-3 candidate vaccines increased attenuation for volunteers, yet also decreased infectivity and immunogenicity. This effect was less clear for DENV-4 candidate vaccines following 15 and 20 PDK cell passages. Only one passage level each of the tested DENV-2, -3, and -4 vaccine candidates was judged acceptably reactogenic and suitable for expanded clinical study. Subsequent studies with more recipients will further establish safety and immunogenicity of the four selected vaccine candidates: DENV-1 45AZ5 PDK 20, DENV-2 S16803 PDK 50, DENV-3 CH53489 PDK 20, and DENV-4 341750 PDK 20.
HEMOGLOBIN LEVELS RELATED TO DAYS OF ILLNESS, RACE, AND PLASMODIUM SPECIES IN COLOMBIAN PATIENTS WITH UNCOMPLICATED MALARIA
Authors: ZAMORA FELIPE , RAMÍREZ OSCAR , VERGARA JUANA , ARÉVALO-HERRERA MYRIAM , HERRERA SÓCRATES
Published: May 2017

Prevalence of malaria-related anemia in disease-endemic regions of the American continents has been poorly studied. We describe the relationships between hemoglobin level and race, Plasmodium species, and days of illness in 150 Colombian patients with uncomplicated malaria diagnosed by thick blood smear. Hemoglobin was measured at admission and a standardized questionnaire was used to determine days of illness and other variables. Associations between hemoglobin and the variables were estimated and adjusted according to the other covariates using regression analysis. Plasmodium falciparum and P. vivax were found in similar proportions and mild anemia was present in 50% of the patients. Volunteers were classified as Afro-Colombians (61%) and non-Afro-Colombians (39%). An inverse relationship between hemoglobin and days of illness was identified, and a statistical interaction was found between race and P. falciparum infection in determining the hemoglobin concentration. These observations could guide the design of research to better understand malarial anemia.
RESTRICTED GENETIC DIVERSITY OF PLASMODIUM FALCIPARUM MAJOR MEROZOITE SURFACE PROTEIN 1 IN ISOLATES FROM COLOMBIA
Authors: TERRIENTES ZILKA I. , VERGARA JUANA , KRAMER KENTON , HERRERA SÓCRATES , CHANG SANDRA P.
Published: May 2017

The merozoite surface protein 1 (MSP-1) gene of Plasmodium falciparum encodes a major immune target under development as a malaria vaccine. In this study, we typed MSP-1 variable regions of parasites obtained from Buenaventura, Colombia. Four MSP-1 gene types were detected corresponding to prototype and recombinant K1 and MAD20 block 4 sequences. In contrast to variability within block 4, blocks 2, 6, and 16–17 corresponded exclusively to the MAD20 allelic type. Most (80%) blood samples contained multiple MSP-1 gene types. The presence of four MSP-1 variants within block 4 against a MAD20 background indicates that current P. falciparum populations in Buenaventura are derived from parasites expressing K1 and MAD20 alleles, some of which underwent two recombination events within or flanking block 4. Restricted MSP-1 diversity appears to be relatively stable in Buenaventura and suggests that selection has resulted in the dominance of the MAD20 type in most of the polymorphic blocks with the exception of block 4.
AN EPIDEMIOLOGIC MODEL OF THE INCIDENCE OF ACUTE ILLNESS IN PLASMODIUM FALCIPARUM MALARIA
Authors: SMITH THOMAS , ROSS AMANDA , MAIRE NICOLAS , ROGIER CHRISTOPHE , TRAPE JEAN-FRANÇOIS , MOLINEAUX LOUIS
Published: May 2017

We propose a stochastic model for simulating malaria tolerance. The model relates the probability of a clinical attack of malaria to the peripheral parasite densities via a pyrogenic threshold that itself responds dynamically to the parasite load. The parameters of the model have been estimated by fitting it to the relationship between incidence of clinical episodes and the entomologic inoculation rate, using age-specific incidence data from two villages in Senegal and one village in Tanzania. The model reproduces the shifts in age distribution of clinical episodes associated with variation in transmission intensity, and in keeping with the data, predicts a slightly higher lifetime number of episodes in the mesoendemic village of Ndiop than in the holoendemic village of Dielmo. This model provides a parsimonious explanation of counter-intuitive relationships between the overall incidence of clinical malaria and transmission intensity. In contrast to the theory of endemic stability, recently proposed to apply to P. falciparum, it does not assume any intrinsic age dependence in the outcome of infection. This model can be used to explore the consequences for predictions of the effects of different anti-malarial interventions on the incidence of clinical malaria.
THE EFFECT OF MALARIA TRANSMISSION INTENSITY ON NEONATAL MORTALITY IN ENDEMIC AREAS
Authors: ROSS AMANDA , SMITH THOMAS
Published: May 2017

Estimates of the impact of Plasmodium falciparum infections during pregnancy on neonatal mortality have not taken into account how this varies with the level of malaria endemicity and thus do not indicate the possible effects of malaria control strategies that reduce transmission. We now review the relevant literature, and propose a mathematical model for the association between P. falciparum transmission and neonatal death. The excess risk of neonatal mortality in malaria-endemic areas appears to be insensitive to the intensity of P. falciparum transmission over a wide range of endemicity. Moderate reductions in the overall level of malaria transmission in endemic areas are therefore unlikely to significantly reduce neonatal mortality. The magnitude of the excess risk is very uncertain because existing estimates are heavily dependent on the questionable assumption that the effects are mediated by birth weight. Accurate prediction of the impact of malaria control measures targeted at pregnant women requires direct estimates of malaria-attributable neonatal mortality rates.
REGULAÇÃO AMBIENTAL DA ATIVIDADE MINERÁRIA: UMA ANÁLISE ECONÔMICA DE COMPLIANCE
Authors: Gomes Magno Federici , Bastianetto Lorena Machado Rogedo
Published: May 2017

Este trabalho foca-se no estudo da sistemática de regulação ambiental brasileira voltada para a atividade de mineração. Ao se valer da vertente metodológica jurídico-dogmática e do raciocínio lógico-dedutivo, procura-se delinear os aspectos de influência mais relevantes na concretização dos objetivos da atividade regulatória, quais sejam: participação dos atores sociais na formação da norma, compliance, fiscalização indireta, monitoramento contínuo e governança ambiental. A economia comportamental e as políticas públicas regulatórias são o cerne do trabalho para a compreensão das razões de sucesso ou colapso da performance regulatória. No desfecho, busca-se maior reflexividade acerca do processo normativo, sugerindo-se a construção de um critério legítimo para nomeação de conselheiros e a criação de mecanismos de abertura do conselho regulador à participatividade difusa.
Carbon and nutrient export regimes from headwater
catchments to downstream reaches
Authors: Dupas Rémi , Musolff Andreas , Jawitz James W. , Rao P. Suresh C. , Jäger Christoph G. , Fleckenstein Jan H. , Rode Michael , Borchardt Dietrich
Published: May 2017

Abstract. Excessive amounts of nutrients and dissolved organic matter in freshwater bodies affect aquatic ecosystems. In this study, the spatial and temporal variability in nitrate (NO3), dissolved organic carbon (DOC) and soluble reactive phosphorus (SRP) was analyzed in the Selke (Germany) river continuum from headwaters draining 1–3 km2 catchments to downstream reaches representing spatially integrated signals from 184–456 km2 catchments. Three headwater catchments were selected as archetypes of the main landscape units (land use x lithology) present in the Selke catchment. Export regimes in headwater catchments were interpreted in terms of NO3, DOC and SRP land-to-stream transfer processes. Headwater signals were subtracted from downstream signals, with the differences interpreted in terms of in-stream processes and contribution of point-source emissions. The seasonal dynamics for NO3 were opposite those of DOC and SRP in all three headwater catchments, and spatial differences also showed NO3 contrasting with DOC and SRP. These dynamics were interpreted as the result of the interplay of hydrological and biogeochemical processes, for which riparian zones were hypothesized to play a determining role. In the two downstream reaches, NO3 was transported almost conservatively, whereas DOC was consumed and produced in the upper and lower river sections, respectively. The natural export regime of SRP in the three headwater catchments mimicked a point-source signal (high SRP during summer low flow), which may lead to overestimation of domestic contributions in the downstream reaches. Monitoring the river continuum from headwaters to downstream reaches proved effective to investigate jointly land-to-stream and in-stream transport and transformation processes.