17 results on '"Konate, Siaka"'
Search Results
2. Monitoring and controlling humidity and pH use of LoRa in IoT-Based hydroponic planting.
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Usman, Achmad, Andani, Yuyun, Satra, Ramdan, Tribuana, Dhimas, and Konate, Siaka
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HUMIDITY control ,SUPPLY chain management ,SECURITY systems ,FOOD production ,TECHNOLOGICAL progress - Abstract
Indonesia, a tropical country with a growing population, has significant potential for food production but faces challenges in meeting this demand. Factors such as generation change, industrialization, food production monopolies, climate change, food security measures, and a lack of technological progress affect productivity. Governments must address these problems by implementing cost efficiency, supply chain management, minimum labor consumption, and adequate food distribution. Food security is vital to the health and well-being of the population, and food is a vital food source to consume. Vegetables, a popular food source, are vital for health and growth. Salad, a plant used for food production, is beneficial to food production and is the leading food in the modern market. Technologically speaking, food security is vital to the health and well-being of the population. Governments should focus on improving food security and ensuring that food is accessible to all. The proposed system consists of five sensors: the DHT11 sensor, the TDS meter, the humidity sensor (DS18B20), the water height sensor, and the pH meter. Data from the sensor will be stored in a cloud database via the LoRa communication network, allowing users to access data through Android applications. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Mapping dengue vulnerability: spatial cluster analysis reveals patterns in Central Java, Indonesia.
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Fithriyyah, Anisahtul, Purwaningsih, Tuti, Konate, Siaka, and Ali Abdalla, Modawy Adam
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CLUSTER analysis (Statistics) ,ARBOVIRUS diseases ,DENGUE ,STANDARD deviations ,COMMUNICABLE diseases ,BASIC needs ,FENITROTHION - Abstract
In Indonesia, where the interplay between climate variability and infectious diseases is pronounced, Dengue Fever poses a significant threat, particularly in Central Java, ranking as the province with the third-highest incidence of Dengue cases nationwide. This study adopts a proactive approach, employing cluster analysis techniques--single linkage, average linkage, and Ward's method--to categorize cities and regencies in Central Java based on their susceptibility to Dengue outbreaks. The comparative analysis, facilitated by standard deviation values, reveals nuanced vulnerability patterns, with the single linkage method presenting the most refined categorization, yielding four distinct vulnerability clusters: very low (0.097), low (0.150), medium (0.205), and high (0.303). Furthermore, spatial analysis utilizing Moran's Index indicates a positive spatial autocorrelation among Dengue cases (Moran's I = 0.62, p < 0.05), underscoring the spatial homogeneity in case distribution across regions. These findings emphasize the critical need for targeted interventions and evidence-based policymaking to effectively combat Dengue transmission in Central Java and mitigate its public health impact. [ABSTRACT FROM AUTHOR]
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- 2023
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4. Deep learning approaches for MIMO time-series analysis.
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Kurniawan, Fachrul, Sulaiman, Sarina, Konate, Siaka, and Abdalla, Modawy Adam Ali
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DEEP learning ,STOCK price forecasting ,CONVOLUTIONAL neural networks ,LONG-term memory ,STANDARD deviations ,RECURRENT neural networks ,TIME series analysis - Abstract
This study presents a comparative analysis of various deep learning (DL) methods for multi-input and multi-output (MIMO) time-series forecasting of stock prices. The analysis is conducted on a dataset comprising the stock price of Bitcoin. The dataset consists of 2950 rows from December 2017 to December 2021. This study aims to evaluate the performance of multiple DL methods, including Multilayer Perceptron (MLP), Convolutional Neural Network (CNN), Recurrent Neural Network (RNN), Long Short Term Memory (LSTM), Bidirectional LSTM (Bi- LSTM), and Gated Recurrent Unit (GRU). The evaluation criteria for selecting the best-performing methods in this research are based on two performance metrics: Mean Absolute Percentage Error (MAPE) and Root Mean Square Error (RMSE). These metrics were chosen for specific reasons related to assessing the accuracy and reliability of the forecasting models. MAPE is used to assess accuracy, while RMSE helps detect outliers in the system. Results show that the LSTM method achieves the best performance, outperforming other methods with an average MAPE value of 8.73% and Bi-LSTM has the best average RMSE value of 0.02216. The findings of this study have practical implications for time-series forecasting in the field of stock trading. The superior performance of LSTM highlights its potential as a reliable method for accurately predicting stock prices. The Bi-LSTM model's ability to detect outliers can aid in identifying abnormal stock market behavior. In summary, this research provides insights into the performance of various DL models of MIMO for stock price forecasting. The results contribute to the field of time-series forecasting and offer valuable guidance for decision-making in stock trading by identifying the most effective methods for predicting stock prices accurately and detecting unusual market behavior. [ABSTRACT FROM AUTHOR]
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- 2023
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5. Use of High-Dose, Twice-Yearly Albendazole and Ivermectin to Suppress Wuchereria bancrofti Microfilarial Levels
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Dembele, Benoit, Coulibaly, Yaya I., Dolo, Housseini, Konate, Siaka, Coulibaly, Siaka Y., Sanogo, Dramane, Soumaoro, Lamine, Coulibaly, Michel E., Doumbia, Salif Seriba, Diallo, Abdallah A., Traore, Sekou F., Keita, Adama Diaman, Fay, Michael P., Nutman, Thomas B., and Klion, Amy D.
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- 2010
6. A randomized trial of doxycycline for mansonella perstans infection
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Coulibaly, Yaya I., Dembele, Benoit, Diallo, Abdallah A., Lipner, Ettie M., Doumbia, Salif S., Coulibaly, Siaka Y., Konate, Siaka, Diallo, Dapa A., Yalcouye, Daniel, Kubofcik, Joseph, Doumbo, Ogobara K., Traore, Sekou F., Keita, Adama D., Fay, Michael P., Nutman, Thomas B., and Kilion, Amy D.
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Doxycycline -- Usage ,Roundworm infections -- Care and treatment - Abstract
A study was conducted to evaluate the efficacy of doxycycline in the treatment of mansonella perstans infection. Results indicated that doxycycline was found to be an effective treatment option for the ailment, and also that mansonella perstans infection does contain bacterial endosymbionts.
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- 2009
7. Factors Associated with Wuchereria bancrofti Microfilaremia in an Endemic Area of Mali.
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Dolo, Housseini, Coulibaly, Yaya Ibrahim, Kelly-Hope, Louise, Konate, Siaka, Dembele, Benoit, Coulibaly, Siaka Yamoussa, Sanogo, Dramane, Soumaoro, Lamine, Coulibaly, Michel Emmanuel, Doumbia, Salif Seriba, Diallo, Abdallah Amadou, Traore, Sekou Fantamady, Colebunders, Robert, Nutman, Thomas B., and Klion, Amy D.
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- 2018
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8. Patent Filarial Infection Modulates Malaria-Specific Type 1 Cytokine Responses in an IL-10-Dependent Manner in a Filaria/Malaria Coinfected Population 1
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Metenou, Simon, Dembele, Benoit, Konate, Siaka, Dolo, Housseini, Coulibaly, Siaka Y., Coulibaly, Yaya I., Diallo, Abdallah A., Soumaoro, Lamine, Coulibaly, Michel E., Sanogo, Dramane, Doumbia, Salif S., Wagner, Marissa, Traoré, Sekou F., Klion, Amy, Mahanty, Siddhartha, and Nutman, Thomas B.
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Interferon-gamma ,Endemic Diseases ,Plasmodium falciparum ,Immunity ,Animals ,Cytokines ,Humans ,Cross Reactions ,Malaria, Falciparum ,Interleukin-12 ,Article ,Filariasis ,Interleukin-10 - Abstract
The effect of filarial infections on malaria-specific immune responses was investigated in Malian villages coendemic for filariasis (Fil) and malaria. Cytokines were measured from plasma and Ag-stimulated whole blood from individuals with Wuchereria bancrofti and/or Mansonella perstans infections (Fil(+); n = 19) and those without evidence of filarial infection (Fil(-); n = 19). Plasma levels of IL-10 (geometric mean [GM], 22.8 vs 10.4) were higher in Fil(+) compared with Fil(-), whereas levels of IFN-inducible protein (IP)-10 were lower in Fil(+) (GM, 66.3 vs 110.0). Fil(+) had higher levels of spontaneously secreted IL-10 (GM, 59.3 vs 6.8 pg/ml) and lower levels of IL-2 (1.0 vs 1.2 pg/ml) than did Fil(-). Although there were no differences in levels of Staphylococcus aureus enterotoxin B-induced cytokines between the two groups, Fil(+) mounted lower IL-12p70 (GM, 1.11 vs 3.83 pg/ml; p = 0.007), IFN-gamma (GM, 5.44 vs 23.41 pg/ml; p = 0.009), and IP-10 (GM, 29.43 vs 281.7 pg/ml; p = 0.007) responses following malaria Ag (MalAg) stimulation compared with Fil(-). In contrast, Fil(+) individuals had a higher MalAg-specific IL-10 response (GM, 7318 pg/ml vs 3029 pg/ml; p = 0.006) compared with those without filarial infection. Neutralizing Ab to IL-10 (but not to TGFbeta) reversed the down-regulated MalAg-specific IFN-gamma and IP-10 (p0.001) responses in Fil(+). Together, these data demonstrate that filarial infections modulate the Plasmodium falciparum-specific IL-12p70/IFN-gamma secretion pathways known to play a key role in resistance to malaria and that they do so in an IL-10-dependent manner.
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- 2009
9. Dynamics of antigenemia and transmission intensity of Wuchereria bancrofti following cessation of mass drug administration in a formerly highly endemic region of Mali.
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Coulibaly, Yaya I., Coulibaly, Siaka Y., Dolo, Housseini, Konate, Siaka, Diallo, Abdallah A., Doumbia, Salif S., Soumaoro, Lamine, Coulibaly, Michel E., Dicko, Ilo, Sangare, Moussa B., Dembele, Benoit, Sangare, Modibo, Dembele, Massitan, Touré, Yeya T., Kelly-Hope, Louise, Polman, Katja, Kyelem, Dominique, Traore, Sekou F., Bockarie, Moses, and Klion, Amy D.
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NEMATODE control ,NEMATODE transmission ,PUBLIC health ,ENDEMIC diseases ,DRUG efficacy ,DRUG administration - Abstract
Background: After seven annual rounds of mass drug administration (MDA) in six Malian villages highly endemic for Wuchereria bancrofti (overall prevalence rate of 42.7%), treatment was discontinued in 2008. Surveillance was performed over the ensuing 5 years to detect recrudescence. Methods: Circulating filarial antigen (CFA) was measured using immunochromatographic card tests (ICT) and Og4C3 ELISA in 6-7 year-olds. Antibody to the W. bancrofti infective larval stage (L3) antigen, Wb123, was tested in the same population in 2012. Microfilaraemia was assessed in ICT-positive subjects. Anopheles gambiae complex specimens were collected monthly using human landing catch (HLC) and pyrethrum spray catch (PSC). Anopheles gambiae complex infection with W. bancrofti was determined by dissection and reverse transcriptase polymerase chain reaction (RT-PCR) of mosquito pools. Results: Annual CFA prevalence rates using ICT in children increased over time from 0% (0/289) in 2009 to 2.7% (8/301) in 2011, 3.9% (11/285) in 2012 and 4.5% (14/309) in 2013 (trend X
2 = 11.85, df =3, P = 0.0006). Wb123 antibody positivity rates in 2013 were similar to the CFA prevalence by ELISA (5/285). Although two W. bancrofti-infected Anopheles were observed by dissection among 12,951 mosquitoes collected by HLC, none had L3 larvae when tested by L3-specific RT-PCR. No positive pools were detected among the mosquitoes collected by pyrethrum spray catch. Whereas ICT in 6-7 year-olds was the major surveillance tool, ICT positivity was also assessed in older children and adults (8-65 years old). CFA prevalence decreased in this group from 4.9% (39/800) to 3.5% (28/795) and 2.8% (50/1,812) in 2009, 2011 and 2012, respectively (trend X2 = 7.361, df =2, P = 0.0067). Some ICT-positive individuals were microfilaraemic in 2009 [2.6% (1/39)] and 2011 [8.3% (3/36)], but none were positive in 2012 or 2013. Conclusion: Although ICT rates in children increased over the 5-year surveillance period, the decrease in ICT prevalence in the older group suggests a reduction in transmission intensity. This was consistent with the failure to detect infective mosquitoes or microfilaraemia. The threshold of ICT positivity in children may need to be re-assessed and other adjunct surveillance tools considered. [ABSTRACT FROM AUTHOR]- Published
- 2016
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10. The Impact of Six Annual Rounds of Mass Drug Administration on Wuchereria bancrofti Infections in Humans and in Mosquitoes in Mali.
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Coulibaly, Yaya I., Dembele, Benoit, Diallo, Abdallah Amadou, Konate, Siaka, Dolo, Houseini, Coulibaly, Siaka Yamoussa, Doumbia, Salif Seriba, Soumaoro, Lamine, Coulibaly, Michel Emmanuel, Bockarie, Moses J., Molyneux, David, Nutman, Thomas B., Klion, Amy D., Toure, Yeya T., and Traore, Sekou F.
- Published
- 2015
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11. Wuchereria bancrofti transmission pattern in southern Mali prior to and following the institution of mass drug administration.
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Ibrahim Coulibaly, Yaya, Dembele, Benoit, Amadou Diallo, Abdallah, Kristensen, Sibylle, Konate, Siaka, Dolo, Housseini, Dicko, Ilo, Brema Sangare, Moussa, Keita, Falaye, Boatin, Boakye A., Kader Traore, Abdel, Nutman, Thomas B., Klion, Amy D., Tiemoko Touré, Yeya, and Fantamady Traore, Sekou
- Subjects
DRUG administration ,FILARIASIS ,ANOPHELES ,MOSQUITO vectors ,INFECTIOUS disease transmission - Abstract
Background: The Global Programme to Eliminate Lymphatic Filariasis (GPELF) was launched in 2000 with the goal of stopping transmission of lymphatic filariasis (LF) through yearly mass drug administration (MDA). Although preliminary surveys of the human population in Mali suggested that Wuchereria bancrofti infection was highly endemic in the Sikasso district, baseline entomological data were required to confirm high levels of transmission prior to the selection of villages in this region for a study of the impact of MDA on transmission of LF by anopheline vectors. Methods: W. bancrofti transmission was assessed in 2001 (pre-MDA) and 2002 (post-MDA) in the Central District of Sikasso in southern Mali by dissection of Anopheles mosquitoes caught using the human landing catch (HLC) method. The relative frequencies and molecular forms of An. gambiae complex were determined. Results: The majority (86%) of the anopheline vectors captured were identified as An. gambiae complex, and these accounted for >90% of the entomological inoculation rate (EIR) during both years of the study. There was a dramatic decrease in the number of An. gambiae complex mosquitoes captured and in the An. gambiae complex infectivity rates following MDA, accounting for the observed decrease in EIR in 2002 (from 12.55 to 3.79 infective bites per person during the transmission season). An. funestus complex mosquitoes were responsible for a low level of transmission, which was similar during both years of the study (1.2 infective bites per person during the transmission season in 2001 and 1.03 in 2002). Conclusions: Based on the entomological data from this study, the district of Sikasso was confirmed as an area of high W. bancrofti transmission. This led to the selection of this area for a multi-national study on the effects of MDA on LF transmission by anopheline vectors. Comparison of vector transmission parameters prior to and immediately following the first round of MDA demonstrated a significant decrease in overall transmission. Importantly, the dramatic variability in EIR over the transmission season suggests that the efficacy of MDA can be maximized by delivering drug at the beginning of the rainy season (just prior to the peak of transmission). [ABSTRACT FROM AUTHOR]
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- 2013
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12. Filariasis Attenuates Anemia and Proinflammatory Responses Associated with Clinical Malaria: A Matched Prospective Study in Children and Young Adults
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Dolo, Housseini, Coulibaly, Yaya I., Dembele, Benoit, Konate, Siaka, Coulibaly, Siaka Y., Doumbia, Salif S., Diallo, Abdallah A., Soumaoro, Lamine, Coulibaly, Michel E., Diakite, Seidina A. S., Guindo, Aldiouma, Fay, Michael P., Metenou, Simon, Nutman, Thomas B., and Klion, Amy D.
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MALARIA immunology ,BLOODBORNE infections ,FILARIASIS ,PARASITE antigens ,PARASITEMIA ,ANEMIA - Abstract
Background: Wuchereria bancrofti (Wb) and Mansonella perstans (Mp) are blood-borne filarial parasites that are endemic in many countries of Africa, including Mali. The geographic distribution of Wb and Mp overlaps considerably with that of malaria, and coinfection is common. Although chronic filarial infection has been shown to alter immune responses to malaria parasites, its effect on clinical and immunologic responses in acute malaria is unknown. Methodology/Principal Findings: To address this question, 31 filaria-positive (FIL+) and 31 filaria-negative (FIL−) children and young adults, matched for age, gender and hemoglobin type, were followed prospectively through a malaria transmission season. Filarial infection was defined by the presence of Wb or Mp microfilariae on calibrated thick smears performed between 10 pm and 2 am and/or by the presence of circulating filarial antigen in serum. Clinical malaria was defined as axillary temperature ≥37.5°C or another symptom or sign compatible with malaria infection plus the presence of asexual malaria parasites on a thick blood smear. Although the incidence of clinical malaria, time to first episode, clinical signs and symptoms, and malaria parasitemia were comparable between the two groups, geometric mean hemoglobin levels were significantly decreased in FIL− subjects at the height of the transmission season compared to FIL+ subjects (11.4 g/dL vs. 12.5 g/dL, p<0.01). Plasma levels of IL-1ra, IP-10 and IL-8 were significantly decreased in FIL+ subjects at the time of presentation with clinical malaria (99, 2145 and 49 pg/ml, respectively as compared to 474, 5522 and 247 pg/ml in FIL− subjects). Conclusions/Significance: These data suggest that pre-existent filarial infection attenuates immune responses associated with severe malaria and protects against anemia, but has little effect on susceptibility to or severity of acute malaria infection. The apparent protective effect of filarial infection against anemia is intriguing and warrants further study in a larger cohort. [ABSTRACT FROM AUTHOR]
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- 2012
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13. Use of High-Dose, Twice-Yearly Albendazole and Ivermectin to Suppress Wuchereria bancrofti Microfilarial Levels.
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Benoit Dembele, Coulibaly, Yaya I., Dolo, Housseini, Konate, Siaka, Coulibaly, Siaka Y., Sanogo, Dramane, Soumaoro, Lamine, Coulibaly, Michel E., Doumbia, Salif Seriba, Diallo, Abdallah A., Traore, Sekou F., Keita, Adama Diaman, Michael P. Fay, Nutman, Thomas B., and Klion, Amy D.
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ALBENDAZOLE ,IVERMECTIN ,DRUG dosage ,WORMS ,ULTRASONIC imaging ,ENZYMES - Abstract
Background. Annual mass treatment with albendazole and ivermectin is the mainstay of current strategies to interrupt transmission of Wuchereria bancrofti in Africa. More-effective microfilarial suppression could potentially reduce the time necessary to interrupt transmission, easing the economic burden of mass treatment programs in countries with limited resources. Methods. To determine the effect of increased dose and frequency of albendazole-ivermectin treatment on microfilarial clearance, 51 W. bancrofti microfilaremic residents of an area of W. bancrofti endemicity in Mali were randomized to receive 2 doses of annual, standard-dose albendazole-ivermectin therapy (400 mg and 150 mg/kg; ) np26 or 4 doses of twice-yearly, increased-dose albendazole-ivermectin therapy (800 mg and 400 mg/kg; np 25). Results. Although microfilarial levels decreased significantly after therapy in both groups, levels were significantly lower in the high-dose, twice-yearly group at 12, 18, and 24 months. Furthermore, there was complete clearance of detectable microfilariae at 12 months in the 19 patients in the twice-yearly therapy group with data available at 12 months, compared with 9 of 21 patients in the annual therapy group (P ! .001, by Fisher's exact test). This difference between the 2 groups was sustained at 18 and 24 months, with no detectable microfilariae in the patients receiving twice-yearly treatment. Worm nests detectable by ultrasonography and W. bancrofti circulating antigen levels, as measured by enzyme-linked immunosorbent assay, were decreased to the same degree in both groups at 24 months, compared with baseline. Conclusions. These findings suggest that increasing the dosage and frequency of albendazole-ivermectin treatment enhances suppression of microfilariae but that this effect may not be attributable to improved adulticidal activity. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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14. Filarial Infection Suppresses Malaria-Specific Multifunctional Th1 and Th17 Responses in Malaria and Filarial Coinfections.
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Metenou, Simon, Dembele, Benoit, Konate, Siaka, Housseini Dolo, Coulibaly, Yaya I., Diallo, Abdallah A., Soumaoro, Lamine, Coulibaly, Michel E., Coulibaly, Siaka Y., Sanogo, Dramane, Doumbia, Salif S., Traoré, Sekou F., Mahanty, Siddhartha, Klion, Amy, and Nutman, Thomas B.
- Subjects
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FILARIASIS , *MALARIA , *PLASMODIUM falciparum , *HELMINTHIASIS , *IMMUNE response , *FLOW cytometry - Abstract
The mechanisms underlying the modulation of both the malaria-specific immune response and the course of clinical malaria in the context of concomitant helminth infection are poorly understood. We used multiparameter flow cytometry to characterize the quality and the magnitude of malaria-specific T cell responses in filaria-infected and -uninfected individuals with concomitant asymptomatic Plasmodium falciparum malaria in Mali. In comparison with filarial-uninfected subjects, filarial infection was associated with higher ex vivo frequencies of CD4+ cells producing IL-4, IL-10, and IL-17A (p = 0.01, p = 0.001, and p = 0.03, respectively). In response to malaria Ag stimulation, however, filarial infection was associated with lower frequencies of CD4+ T cells producing IFN-γ, TNF-α, and IL-17A (p < 0.001, p = 0.04, and p = 0.04, respectively) and with higher frequencies of CD4+IL10+T cells (p = 0.0005). Importantly, filarial infection was associated with markedly lower frequencies of malaria Ag-specific Th1 (p < 0.0001), Th17 (p = 0.012), and "TNF-α" (p = 0.0008) cells, and a complete absence of malaria-specific multifunctional Th1 cells. Filarial infection was also associated with a marked increase in the frequency of malaria-specific adaptive regulatory T/Tr1 cells (p = 0.024), and the addition of neutralizing anti-IL-10 Ab augmented the amount of Th1-associated cytokine produced per cell. Thus, among malaria-infected individuals, concomitant filarial infection diminishes dramatically the frequencies of malaria-specific Th1 and Th17 T cells, and alters the quality and magnitude of malaria-specific T cell responses. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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15. Expanded numbers of circulating myeloid dendritic cells in patent human filarial infection reflect lower CCR1 expression.
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Semnani RT, Mahapatra L, Dembele B, Konate S, Metenou S, Dolo H, Coulibaly ME, Soumaoro L, Coulibaly SY, Sanogo D, Seriba Doumbia S, Diallo AA, Traoré SF, Klion A, Nutman TB, and Mahanty S
- Subjects
- Adult, Animals, Brugia malayi immunology, Cell Separation, Chemotaxis, Leukocyte immunology, Clinical Trials as Topic, Dendritic Cells metabolism, Dipetalonema Infections immunology, Female, Filariasis blood, Flow Cytometry, Humans, Male, Mansonella, Mansonelliasis blood, Mansonelliasis immunology, Middle Aged, Myeloid Cells immunology, Myeloid Cells metabolism, Receptors, CCR1 immunology, Reverse Transcriptase Polymerase Chain Reaction, Wuchereria bancrofti immunology, Dendritic Cells immunology, Filariasis immunology, Receptors, CCR1 biosynthesis
- Abstract
APC dysfunction has been postulated to mediate some of the parasite-specific T cell unresponsiveness seen in patent filarial infection. We have shown that live microfilariae of Brugia malayi induce caspase-dependent apoptosis in human monocyte-derived dendritic cells (DCs) in vitro. This study addresses whether apoptosis observed in vitro extends to patent filarial infections in humans and is reflected in the number of circulating myeloid DCs (mDCs; CD11c(-)CD123(lo)) in peripheral blood of infected microfilaremic individuals. Utilizing flow cytometry to identify DC subpopulations (mDCs and plasmacytoid DCs [pDCs]) based on expression of CD11c and CD123, we found a significant increase in numbers of circulating mDCs (CD11c(+)CD123(lo)) in filaria-infected individuals compared with uninfected controls from the same filaria-endemic region of Mali. Total numbers of pDCs, monocytes, and lymphocytes did not differ between the two groups. To investigate potential causes of differences in mDC numbers between the two groups, we assessed chemokine receptor expression on mDCs. Our data indicate that filaria-infected individuals had a lower percentage of circulating CCR1(+) mDCs and a higher percentage of circulating CCR5(+) mDCs and pDCs. Finally, live microfilariae of B. malayi were able to downregulate cell-surface expression of CCR1 on monocyte-derived DCs and diminish their calcium flux in response to stimulation by a CCR1 ligand. These findings suggest that microfilaria are capable of altering mDC migration through downregulation of expression of some chemokine receptors and their signaling functions. These observations have major implications for regulation of immune responses to these long-lived parasites.
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- 2010
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16. At homeostasis filarial infections have expanded adaptive T regulatory but not classical Th2 cells.
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Metenou S, Dembele B, Konate S, Dolo H, Coulibaly SY, Coulibaly YI, Diallo AA, Soumaoro L, Coulibaly ME, Sanogo D, Doumbia SS, Traoré SF, Mahanty S, Klion A, and Nutman TB
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- Animals, Cytokines biosynthesis, Enterobiasis immunology, Enterobius immunology, Humans, Hymenolepiasis immunology, Hymenolepis nana immunology, Mansonella immunology, Microfilariae immunology, T-Lymphocytes, Regulatory metabolism, T-Lymphocytes, Regulatory parasitology, Th2 Cells metabolism, Th2 Cells parasitology, Wuchereria bancrofti immunology, Adaptive Immunity, Elephantiasis, Filarial immunology, Homeostasis immunology, Mansonelliasis immunology, T-Lymphocytes, Regulatory immunology, Th2 Cells immunology
- Abstract
Despite the well-documented immune suppression associated with human helminth infections, studies characterizing the immune response at the single-cell level are scanty. We used multiparameter flow cytometry to characterize the type of effector (Th1, Th2, and Th17) and regulatory (natural T regulatory cells [nTregs] and adaptive Treg cells [aTreg/type 1 regulatory cells (Tr1s)]) CD4(+) and CD8(+) T cells in filaria-infected (Fil(+)) and -uninfected (Fil(-)) individuals at homeostasis (in the absence of stimulation). Frequencies of CD4(+) lymphocytes spontaneously producing IL-4, IL-10, and IL-17A were significantly higher in Fil(+), as were those of IL-10(+)/IL-4(+) double-producing CD4(+) cells. Interestingly, frequencies of Th17 and aTreg/Tr1s but not classical Th1 or Th2 cells were significantly increased in Fil(+) compared to Fil(-) individuals. Although the frequency of nTreg was increased in Fil(+), IL-10 was overwhelmingly produced by CD4(+)CD25(-) cells. Moreover, the concentration of IL-10 produced spontaneously in vitro strongly correlated with the integrated geometric mean fluorescence intensity of IL-10-producing aTreg/Tr1s in Fil(+). Together, these data show that at steady state, IL-10-producing aTreg/Tr1 as well as nTreg and effector Th17 CD4(+) cells are expanded in vivo in human filarial infections. Moreover, we have established baseline ex vivo frequencies of effector and Tregs at homeostasis at a population level.
- Published
- 2010
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17. Patent filarial infection modulates malaria-specific type 1 cytokine responses in an IL-10-dependent manner in a filaria/malaria-coinfected population.
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Metenou S, Dembélé B, Konate S, Dolo H, Coulibaly SY, Coulibaly YI, Diallo AA, Soumaoro L, Coulibaly ME, Sanogo D, Doumbia SS, Wagner M, Traoré SF, Klion A, Mahanty S, and Nutman TB
- Subjects
- Animals, Cross Reactions immunology, Cytokines metabolism, Endemic Diseases, Filariasis immunology, Humans, Immunity, Interferon-gamma metabolism, Interleukin-12 metabolism, Malaria, Falciparum immunology, Plasmodium falciparum immunology, Cytokines immunology, Filariasis complications, Interleukin-10 blood, Malaria, Falciparum complications
- Abstract
The effect of filarial infections on malaria-specific immune responses was investigated in Malian villages coendemic for filariasis (Fil) and malaria. Cytokines were measured from plasma and Ag-stimulated whole blood from individuals with Wuchereria bancrofti and/or Mansonella perstans infections (Fil(+); n = 19) and those without evidence of filarial infection (Fil(-); n = 19). Plasma levels of IL-10 (geometric mean [GM], 22.8 vs 10.4) were higher in Fil(+) compared with Fil(-), whereas levels of IFN-inducible protein (IP)-10 were lower in Fil(+) (GM, 66.3 vs 110.0). Fil(+) had higher levels of spontaneously secreted IL-10 (GM, 59.3 vs 6.8 pg/ml) and lower levels of IL-2 (1.0 vs 1.2 pg/ml) than did Fil(-). Although there were no differences in levels of Staphylococcus aureus enterotoxin B-induced cytokines between the two groups, Fil(+) mounted lower IL-12p70 (GM, 1.11 vs 3.83 pg/ml; p = 0.007), IFN-gamma (GM, 5.44 vs 23.41 pg/ml; p = 0.009), and IP-10 (GM, 29.43 vs 281.7 pg/ml; p = 0.007) responses following malaria Ag (MalAg) stimulation compared with Fil(-). In contrast, Fil(+) individuals had a higher MalAg-specific IL-10 response (GM, 7318 pg/ml vs 3029 pg/ml; p = 0.006) compared with those without filarial infection. Neutralizing Ab to IL-10 (but not to TGFbeta) reversed the down-regulated MalAg-specific IFN-gamma and IP-10 (p < 0.001) responses in Fil(+). Together, these data demonstrate that filarial infections modulate the Plasmodium falciparum-specific IL-12p70/IFN-gamma secretion pathways known to play a key role in resistance to malaria and that they do so in an IL-10-dependent manner.
- Published
- 2009
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