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1.

Background

Asymptomatic Plasmodium spp. infections and anemia are highly prevalent conditions in tropical regions. We studied whether asymptomatic parasitemia induces hepcidin- and/or cytokine-mediated iron maldistribution and anemia.

Design and Methods

A group of 1197 Indonesian schoolchildren, aged 5–15 years, were screened by microscopy for the presence of parasitemia. Concentrations of hemoglobin, serum hepcidin and parameters of iron status and inflammation were determined at baseline and 4 weeks after antimalarial treatment.

Results

Asymptomatic P. falciparum and P. vivax parasitemia were detected in 73 (6.1%) and 18 (1.5%) children, respectively, of whom 84% and 83% had a C-reactive protein concentration below 5 mg/L. Children with P. falciparum or P. vivax parasitemia had significantly lower hemoglobin concentrations than 17 aparasitemic controls (12.6 and 12.2 g/dL versus 14.4 g/dL; P<0.01), together with significantly higher serum hepcidin concentrations (5.2 and 5.6 nM versus 3.1 nM; P<0.05). The latter was associated with signs of iron maldistribution with higher ferritin concentrations and lower values of serum iron concentration, transferrin saturation and erythrocyte mean cell volume. Concentrations of growth differentiation factor 15 were similar across groups. Antimalarial treatment partly reversed these abnormalities and led to a significant increase in hemoglobin concentration.

Conclusions

Asymptomatic malarial parasitemia is associated with increased hepcidin concentrations and anemia, in the absence of a manifest acute phase response. Prolonged iron maldistribution may be an underestimated cause of anemia. Screening for parasitemia should be performed before starting iron supplementation, as iron therapy may be less effective and even hazardous in these circumstances.  相似文献   

2.
BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) colonization is increasingly of concern in community settings. However, despite a recent outbreak in Calgary, Alberta, data on the prevalence of MRSA in Canadian communities are lacking. Globally, few studies have been performed in high-risk groups such as inner-city populations. METHODS: A cross-sectional study of the prevalence of MRSA among residents and staff at three Ottawa, Ontario, shelters was conducted. All participants completed a questionnaire, and provided nasal swabs as well as one of rectal, anal or groin swabs. RESULTS: Among 84 participants, the prevalence of MRSA colonization was 2.4%. Among the resident subgroup, the prevalence was 4.5%, while no MRSA isolates were found among 40 staff participants. All isolates were USA100 (CMRSA-2) subtypes. CONCLUSIONS: The prevalence of MRSA colonization among residents is higher than baseline population rates, but is consistent with other inner-city populations. Although community outbreaks of USA300 and USA400 strains are increasingly reported, movement of nosocomial strains (ie, USA100 [CMRSA-2]) into communities remains an important avenue in the spread of MRSA and underscores the importance of nosocomial MRSA control.  相似文献   

3.
Vitamin D deficiency is associated with susceptibility to tuberculosis (TB) in HIV-uninfected people in Europe, but it is not known whether such an association exists among HIV-infected people in subtropical Africa. We conducted a cross-sectional study to determine whether vitamin D deficiency was associated with susceptibility to active TB in HIV-uninfected (n = 196) and HIV-infected (n = 174) black Africans in Cape Town, South Africa. We also investigated whether there was evidence of seasonal variation in vitamin D status and TB notifications in this setting over an 8-y period. Vitamin D deficiency (serum 25-hydroxyvitamin D [25(OH)D] <50 nmol/L) was present in 232 (62.7%) of 370 participants and was associated with active TB in both HIV-uninfected (odds ratio = 5.2, 95% confidence interval: 2.8-9.7; P < 0.001) and HIV-infected (odds ratio = 5.6, 95% confidence interval: 2.7-11.6; P < 0.001) people. Vitamin D status varied according to season: The mean serum 25(OH)D concentration was highest in January through March and lowest in July through September (56.8 vs. 30.7 nmol/L, respectively; P < 0.001). Reciprocal seasonal variation in TB notifications was observed: The mean number of TB notifications per quarter for Cape Town in 2003 to 2010 was lowest in April through June and highest in October through December (4,222 vs. 5,080; P < 0.001). Vitamin D deficiency is highly prevalent among black Africans in Cape Town and is associated with susceptibility to active TB both in the presence and absence of HIV infection. Reciprocal seasonal variation in serum 25(OH)D concentration and TB notifications suggests that seasonal variations in vitamin D status and TB incidence in this setting are causally related.  相似文献   

4.
The ability to control fire was a crucial turning point in human evolution, but the question when hominins first developed this ability still remains. Here we show that micromorphological and Fourier transform infrared microspectroscopy (mFTIR) analyses of intact sediments at the site of Wonderwerk Cave, Northern Cape province, South Africa, provide unambiguous evidence--in the form of burned bone and ashed plant remains--that burning took place in the cave during the early Acheulean occupation, approximately 1.0 Ma. To the best of our knowledge, this is the earliest secure evidence for burning in an archaeological context.  相似文献   

5.
6.
This study confirmed the prevalence of the intestinal fluke Haplorchis taichui (Trematoda: Heterophyidae) among people and fish in Luang Prabang Province, Lao PDR. Fecal specimens were collected from 559 riparian people (229 males and 330 females), residing in 4 Districts (Luang Prabang, Xieng Ngeun, Pak Ou, and Nam Bak) and were examined by the Kato-Katz fecal smear technique. The overall helminth egg positive rate was 64.9%. The positive rate for small trematode eggs (STE), which may include H. taichui and other heterophyids, Opisthorchis viverrini, and lecithodendriids, was 15.2%. For recovery of adult helminths, 10 STE-positive people were treated with 40 mg/kg praziquantel and 15 mg/kg pyrantel pamoate, and then purged. Mixed infections with 3 Haplorchis species (H. taichui, H. pumilio, and H. yokogawai), a species of cestode (Taenia saginata), and several species of nematodes including Enterobius vermicularis and hookworms were found. The worm load for trematodes was exclusively high for H. taichui with an average of 7691 specimens per infected person, followed by H. yokogawai (8.3 specimens) and H. pumilio (4.1 specimens). Out of 207 freshwater fish (17 species) purchased in a market in Luang Prabang District, 138 (67%) harboured H. taichui metacercariae (metacercarial burden per fish; 520). Lower prevalence of fish and lower metacercarial density were observed for H. yokogawai (52% and 50 per fish, respectively) and H. pumilio (18% and 3 per fish, respectively). STE found in the surveyed population of Luang Prabang Province were verified to be those of intestinal fukes, particularly H. taichui.  相似文献   

7.
The detection of Trypanosoma evansi in blood is intricate, primarily in chronic stage of infection, as the parasitaemia is often low and fluctuating. The climatic conditions of the target area of Punjab (a province of India with a total of 34,000 horses and ponies used for sports and transport) are conducive for the parasite propagation. The objective of present investigation was to assess the prevalence of T. evansi in central and western Punjab by PCR and card agglutination test (CATT/T. evansi) in relation to clinico-haematobiochemical alterations and risk factors associated with latent trypanosomosis. A total of 169 equine blood and serum samples tested by CATT/T. evansi revealed 16 cases positive, with 6.8% from central plain and 13.63% from western zone. To assess the specificity of serological test, PCR1 was performed using established primer pair TR3 5′-GCG CGG ATT CTT TGC AGA CGA-3′ and TR4 5′-TGC AGA CAC TGG AAT GTT ACT-3′ for T. evansi. PCR2 applied with primer pair RoTat1.2F: 5′-ATG TCA ACG ATG CCT GTT ACA TTA CGC AC-3′ and RoTat1.2R: 5′-TAA ATA TCA CTG TCA AGA CCT GCT GCG G-3′ to rule out the consensus between the finding of the two PCR assays and agglutination test for T. evansi, which displayed results in concordance with PCR1. PCR assays showed 1.92 and 1.51% positive samples from central plain and western zone, respectively. With respect to PCR assay, CATT/T. evansi showed 100% sensitivity and 92.1% specificity. Microscopy showed a very low prevalence rate of 0.59% with only one sample positive with teaming parasitaemia. Comparison between sexes revealed higher positivity in mares by the three tests (BSE: 0.95%, PCR: 2.88%, CATT/T. evansi: 14.42%). The haemato-biochemical factors were found to be altered in PCR positive cases, while the mean value of vital parameters lied in normal range in seropositive cases. The female horse (RR = 0.0937, 95% CI = 1.388–190.223%) population was found to be at the highest risk of seropositivity for T. evansi, particularly in the unorganized farms (RR = 19.726, 95% CI = 2.918–400.221%).  相似文献   

8.
9.
This review summarizes the microbiology, and antimicrobial management of mycotic aneurysm of the aorta (MAA) due to anaerobic bacteria. Anaerobic bacteria are an uncommon but important cause of MAA. Most cases of anaerobic MAA are caused anaerobic gram-negative bacilli (mostly B. fragilis group), Clostridium spp. (mostly Clostridium septicum, and Propionobacterium spp. (mostly P. acnes). Clostridial infection is frequently associated with gastrointestinal or hematologic malignancy. A review of all the reported cases is presented. Treatment of MAA involving anaerobic bacteria includes the use of antimicrobial effective against these organisms.  相似文献   

10.
The Cree communities of James Bay are at risk for contracting infectious diseases transmitted by wildlife. Data from serological testing for a range of zoonotic infections performed in the general population (six communities), or trappers and their spouses (one community), were abstracted from four population-based studies conducted in Cree territory (Quebec) between 2005 and 2009. Evidence of exposure to Trichinella species, Toxoplasma gondii, Toxocara canis, Echinococcus granulosus, Leptospira species, Coxiella burnetii and Francisella tularensis was verified in all communities, whereas antibodies against Sin Nombre virus and California serogroup viruses (Jamestown Canyon and snowshoe hare viruses) were evaluated in three and six communities, respectively. Seroprevalence varied widely among communities: snowshoe hare virus (1% to 42%), F tularensis (14% to 37%), Leptospira species (10% to 27%), Jamestown Canyon virus (9% to 24%), C burnetii (0% to 18%), T gondii (4% to 12%), T canis (0% to 10%), E granulosus (0% to 4%) and Trichinella species (0% to 1%). No subject had serological evidence of Sin Nombre virus exposure. These data suggest that large proportions of the Cree population have been exposed to at least one of the targeted zoonotic agents. The Cree population, particularly those most heavily exposed to fauna, as well as the medical staff living in these regions, should be aware of these diseases. Greater awareness would not only help to decrease exposures but would also increase the chance of appropriate diagnostic testing.  相似文献   

11.
The dynamics of viruses are critical to our understanding of disease pathogenesis. Using honey bee Deformed wing virus (DWV) as a model, we conducted field and laboratory studies to investigate the roles of abiotic and biotic stress factors as well as host health conditions in dynamics of virus replication in honey bees. The results showed that temperature decline could lead to not only significant decrease in the rate for pupae to emerge as adult bees, but also an increased severity of the virus infection in emerged bees, partly explaining the high levels of winter losses of managed honey bees, Apis mellifera, around the world. By experimentally exposing adult bees with variable levels of parasitic mite Varroa destructor, we showed that the severity of DWV infection was positively correlated with the density and time period of Varroa mite infestation, confirming the role of Varroa mites in virus transmission and activation in honey bees. Further, we showed that host conditions have a significant impact on the outcome of DWV infection as bees that originate from strong colonies resist DWV infection and replication significantly better than bee originating from weak colonies. The information obtained from this study has important implications for enhancing our understanding of host‑pathogen interactions and can be used to develop effective disease control strategies for honey bees.  相似文献   

12.
A study of the prevalence, intensity and risk factors for soil-transmitted helminth infection was undertaken among school children aged 5-9 years attending a primary school in the fishing village in Peda Jalaripet, Visakhapatnam, South India. One hundred and eighty nine (92.6%) of 204 children were infected with one or more soil transmitted helminth parasites. The predominant parasite was Ascaris lumbricoides (prevalence of 91%), followed by Trichuris trichiura (72%) and hookworm (54%). Study of age-specific prevalence and intensity of infection revealed that the prevalence and intensity of A. lumbricoides infection was higher among younger children than older children. While aggregation of parasite infection was observed, hookworm infection was more highly aggregated than either A. lumbricoides or T. trichiura. Multivariate analysis identified parental occupation, child's age and mother's education as the potential risk factors contributing to the high intensity of A. lumbricoides infection. Children from fishing families with low levels of education of the mother had the highest intensity of A. lumbricoides infection. As the outcome of chemotherapy programs to control soil transmitted helminth infection is dependant on the dynamics of their transmission, there is a need for further studies to better define the role of specific factors that determine their prevalence, intensity and aggregation in different epidemiological settings.  相似文献   

13.

Background/Aim:

The published data on Helicobacter pylori (H. pylori) prevalence and its relationship with abdominal pain in Saudi Arabia is scarce. This study was carried out to determine the prevalence of H. pylori and its relationship with chronic recurrent abdominal pain (RAP) among school students in Makkah City, Saudi Arabia.

Materials and Methods:

Three hundred and fourteen school students, 103 at the intermediate level (grades 7-9) aged 12-15 years and 211 at the secondary level (grades 10-12) aged 15-18 years were tested for H. pylori. Urea breath test (UBT) was used for this purpose. Children with chronic RAP were identified as per the Apley criteria.

Results:

Overall, the UBT was positive in 86/314 (27.4%) students. It was positive in 45/103 (43.7%) intermediate school students and 41/211 (19.4%) secondary students. Out of the 55 students with chronic RAP, 40 (73%) were positive for H. pylori. Further, 62.9% and 82.1% were positive among the intermediate and secondary school students with RAP, respectively. The overall and specific odds ratios of RAP were 12.35 [95% confidence interval (C.I.) 6.30-24.22] and 10.40 (95% C.I. 1.75-11.73) for the intermediate school students and 22.69 (95% C.I. 7.99-64.44) for the secondary school students.

Conclusion:

The prevalence of H. pylori among the school children in Makkah, Saudi Arabia, is relatively low compared with developing countries. The prevalence was found to be higher among the younger age group. Further, there was a significant relation between H. pylori infection and RAP among the school students.  相似文献   

14.
Prothrombin (F2) 20210G>A [rs1799963 G>A] mutation is a genetic variant which predisposes to inherited thrombophilia. Highest prevalence of this rare mutation has been reported among Caucasian and Mediterranean populations with thrombophilic conditions compared to healthy controls. It is absent or occurs in a very low frequency in both thrombophilic patients and healthy controls of most South Asian populations. A previous study has demonstrated that the mutant allele is absent among Sri Lankan healthy controls. This study was conducted to determine the prevalence of the F2 20210G>A mutation among Sri Lankan patients with thrombo-embolic disorders. F2 20210G>A mutation analysis was carried out on 825 patients. These included 374 with arterial thromboembolic disorders, 303 with venous thromboembolic disorders (VTE) and 148 with pregnancy related complications. Genotyping was done using polymerase chain reaction followed by restriction fragment length polymorphism. The overall prevalence of the individuals detected with the mutation was 0.8 % (7/825) with a mutant allele frequency of 0.4 % (7/1,650), and all were heterozygotes. Further classification according to the types of thrombotic events showed a prevalence of 0.5 % (2/374), 1.3 % (4/303), and 0.7 % (1/148) respectively, in the three groups with arterial thrombosis, VTE and pregnancy complications. The respective mutant allele frequencies in the three different groups were 0.3 % (2/748), 0.7 % (4/606) and 0.3 % (1/296). Although these figures are lower than that of Caucasian and Mediterranean populations, they are relatively higher compared to other South Asian populations. Therefore, the F2 20210G>A mutant allele is not entirely absent among Sri Lankan patients with thrombo-embolic disorders.  相似文献   

15.
16.
17.
In this work we show that the lumen of Aedes aegypti midgut is highly colonized by bacteria that were identified by culture-dependent and culture-independent methods. rDNA sequences obtained were compared with those from GenBank and the main bacterial genera identified were: Serratia, Klebsiella, Asaia, Bacillus, Enterococcus, Enterobacter,Kluyvera and Pantoea. All genera were identified in midgut except Enterobacter that was observed only in eggs. Asaia and Pantoea were also identified in eggs and ovary, respectively. In addition two yeast genera were observed in A. aegypti: Pichia isolated from midgut and Candida identified in midgut and ovary. The genus Serratia was dominant in all isolation assays representing 54.5% of the total of microorganisms. Thirty-nine and 24 bacterial clones were successfully obtained from midguts 24 and 48 h after blood feeding (ABF), respectively. The majority of clones obtained were from Serratia sp. (48.7% and 50% for 24 and 48 h ABF, respectively). Light microscopy showed that bacteria were located preferentially in the posterior midgut, around the blood meal and associated with peritrophic matrix. Scanning electron microscopy images showed a high number of bacteria in midgut during blood digestion and the peak of bacterial enumeration was reached 48 h ABF, stage in which lumen was almost totally occupied by bacteria that were also interacting with epithelial microvilli. Our results show the dynamics of microbial colonization and their distribution in midgut during blood digestion.  相似文献   

18.
Objective:To determine the prevalence of gastrointestinal helminthes and associated risk factors among schoolchildren in Tilili town,northwest Ethiopia.Methods:A cross-sectional study involving 383 schoolchildren was conducted between November 2011 to February 2012.Each student was selected using systematic random sampling method.Questionnaire and observation were used to identify socio-demographic and associated risk factors.Fresh stool samples were observed using formal-ether concentration technique.Data were analyzed using SPSS 16.0statistical software.Results:Four species of intestinal helminthes were identified with an overall prevalence of 44.2%(170 of 385 schoolchildren).The predominant parasites were Ascaris lumbricoides(A.lumbricoides)153(39.7%)and Trichuris trichiura(T.trichiura)30(7.8%).One hundred thirty five(35.1%)had single infections and 35(9.2%)were infected with more than one helminthic parasites in which 32(8.4%)were double infections and 3(0.8%)were triple infections.Significant associations were observed between intestinal helminth infection and those of age,grade level,and school variables.Prevalence of hookworm infection was significant in children who did not wear shoes regularly(P0.05).Conclusions:intervention programs and education on personal and environmental hygiene should be implemented for the prevention and control of helminthic infections in the study area.  相似文献   

19.
INTRODUCTION Eradication of Helicobacter pylori, a bacterium residing in stomach and causing peptic ulcer disease,can be achieved by using combination therapies consisting of one or two antibiotics with a proton pump inhibitor (PPI). The major antibiotics widely used in the regimens to eradicate H. Pylori are metronidazole and clarithromycin[1-3].  相似文献   

20.
Wang Q  Qiu H  Jiang H  Wu L  Dong S  Pan J  Wang W  Ping N  Xia J  Sun A  Wu D  Xue Y  Drexler HG  Macleod RA  Chen S 《Haematologica》2011,96(12):1808-1814

Background

Mutations in the PHF6 gene were recently described in patients with T-cell acute lymphoblastic leukemia and in those with acute myeloid leukemia. The present study was designed to determine the prevalence of PHF6 gene alterations in T-cell acute lymphoblastic leukemia.

Design and Methods

We analyzed the incidence and prognostic value of PHF6 mutations in 96 Chinese patients with T-cell acute lymphoblastic leukemia. PHF6 deletions were screened by real-time quantitative polymerase chain reaction and array-based comparative genomic hybridization. Patients were also investigated for NOTCH1, FBXW7, WT1, and JAK1 mutations together with CALM-AF10, SET-NUP214, and SIL-TAL1 gene rearrangements.

Results

PHF6 mutations were identified in 11/59 (18.6%) adult and 2/37 (5.4%) pediatric cases of T-cell acute lymphoblastic leukemia, these incidences being significantly lower than those recently reported. Although PHF6 is X-linked and mutations have been reported to occur almost exclusively in male patients, we found no sex difference in the incidences of PHF6 mutations in Chinese patients with T-cell acute lymphoblastic leukemia. PHF6 deletions were detected in 2/79 (2.5%) patients analyzed. NOTCH1 mutations, FBXW7 mutations, WT1 mutations, JAK1 mutations, SIL-TAL1 fusions, SET-NUP214 fusions and CALM-AF10 fusions were present in 44/96 (45.8%), 9/96 (9.4%), 4/96 (4.1%), 3/49 (6.1%), 9/48 (18.8%), 3/48 (6.3%) and 0/48 (0%) of patients, respectively. The molecular genetic markers most frequently associated with PHF6 mutations were NOTCH1 mutations (P=0.003), SET-NUP214 rearrangements (P=0.002), and JAK1 mutations (P=0.005). No differences in disease-free survival and overall survival between T-cell acute lymphoblastic leukemia patients with and without PHF6 mutations were observed in a short-term follow-up.

Conclusions

Overall, these results indicate that, in T-cell acute lymphoblastic leukemia, PHF6 mutations are a recurrent genetic abnormality associated with mutations of NOTCH1, JAK1 and rearrangement of SET-NUP214.  相似文献   

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