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1.
Sci Rep ; 14(1): 14355, 2024 06 21.
Article in English | MEDLINE | ID: mdl-38906908

ABSTRACT

Intensification of staple crops through conventional agricultural practices with chemical synthetic inputs has yielded positive outcomes in food security but with negative environmental impacts. Ecological intensification using cropping systems such as maize edible-legume intercropping (MLI) systems has the potential to enhance soil health, agrobiodiversity and significantly influence crop productivity. However, mechanisms underlying enhancement of biological soil health have not been well studied. This study investigated the shifts in rhizospheric soil and maize-root microbiomes and associated soil physico-chemical parameters in MLI systems of smallholder farms in comparison to maize-monoculture cropping systems (MMC). Maize-root and rhizospheric soil samples were collected from twenty-five farms each conditioned by MLI and MMC systems in eastern Kenya. Soil characteristics were assessed using Black oxidation and Walkley methods. High-throughput amplicon sequencing was employed to analyze fungal and bacterial communities, predicting their functional roles and diversity. The different MLI systems significantly impacted soil and maize-root microbial communities, resulting in distinct microbe sets. Specific fungal and bacterial genera and species were mainly influenced and enriched in the MLI systems (e.g., Bionectria solani, Sarocladium zeae, Fusarium algeriense, and Acremonium persicinum for fungi, and Bradyrhizobium elkanii, Enterobacter roggenkampii, Pantoea dispersa and Mitsuaria chitosanitabida for bacteria), which contribute to nutrient solubilization, decomposition, carbon utilization, plant protection, bio-insecticides/fertilizer production, and nitrogen fixation. Conversely, the MMC systems enriched phytopathogenic microbial species like Sphingomonas leidyi and Alternaria argroxiphii. Each MLI system exhibited a unique composition of fungal and bacterial communities that shape belowground biodiversity, notably affecting soil attributes, plant well-being, disease control, and agroecological services. Indeed, soil physico-chemical properties, including pH, nitrogen, organic carbon, phosphorus, and potassium were enriched in MLI compared to MMC cropping systems. Thus, diversification of agroecosystems with MLI systems enhances soil properties and shifts rhizosphere and maize-root microbiome in favor of ecologically important microbial communities.


Subject(s)
Soil Microbiology , Soil , Zea mays , Zea mays/growth & development , Zea mays/microbiology , Soil/chemistry , Agriculture/methods , Rhizosphere , Microbiota , Crops, Agricultural/growth & development , Crops, Agricultural/microbiology , Ecosystem , Plant Roots/microbiology , Plant Roots/growth & development , Biodiversity , Bacteria/classification , Bacteria/genetics , Bacteria/growth & development , Fungi/genetics , Fungi/classification , Kenya , Crop Production/methods
2.
J Chem Ecol ; 2024 May 09.
Article in English | MEDLINE | ID: mdl-38722476

ABSTRACT

The zoophytophagous mirid predator Nesidiocoris tenuis and the ectoparasitoid Stenomesius japonicus are important biological control agents for several agricultural pests including the invasive leafminer, Phthorimaea absoluta, a destructive pest of Solanaceous crops especially tomato in sub-Saharan Africa. However, little is known about how feeding by N. tenuis can influence the tritrophic interactions in the tomato plant. Here, we tested the hypothesis that N. tenuis phytophagy would influence the tritrophic olfactory interactions between the host plant tomato and pest, predator, and parasitoid. In olfactometer assays, P. absoluta females and N. tenuis adults were both attracted to constitutive volatiles released by the tomato plant. Whereas females of P. absoluta avoided volatiles released by N. tenuis-infested plants, S. japonicus females and N. tenuis adults were attracted to the induced volatiles. In coupled gas chromatography-electroantennographic detection (GC-EAD) recordings of intact and N. tenuis-infested plant volatiles, antennae of P. absoluta and S. japonicus females both detected eight components, whereas N. tenuis adults detected seven components which were identified by GC-mass spectrometry (GC-MS) as terpenes and green leaf volatiles (GLVs). Dose-response olfactometer bioassays revealed that the responses of P. absoluta, N. tenuis, and S. japonicus varied with the composition and concentration of blends and individual compounds tested from N tenuis-induced volatiles. Females of P. absoluta showed no preference for an eight-component blend formulated from the individual repellents including hexanal, (Z)-3-hexenyl butanoate, and δ-elemene identified in the volatiles. On the other hand, S. japonicus females were attracted to an eight-component blend including the attractants (E)-2-hexenal, (Z)-3-hexenol, methyl salicylate, ß-phellandrene, and (E)-caryophyllene. Likewise, N. tenuis adults were attracted to a seven-component blend including the attractants ß-phellandrene, δ-elemene, and (E)-caryophyllene identified in the volatiles. Our findings suggest that there is potential for the use of terpenes and GLVs to manage the insects in the tritrophic interaction.

3.
Heliyon ; 10(9): e30068, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38707327

ABSTRACT

Before the introduction of Bactrocera dorsalis (Hendel) to sub-Saharan Africa, Ceratitis cosyra (Walker) was economically the most important pest in mango farming. Its native natural enemy, the solitary parasitoid Psyttalia cosyrae (Wilkinson), played a crucial role in C. cosyra bio-control, later complemented by the exotic parasitoids Diachasmimorpha longicaudata (Ashmead) and Fopius arisanus (Sonan) among Integrated Pest Management (IPM) systems. To understand the in situ mango-C. cosyra-parasitoid tritrophic interaction, we assessed the responses of the fruit fly and the three parasitoids to headspace volatiles from various mango conditions. These conditions included non-infested mature unripe mangoes, C. cosyra-infested mangoes, 7th- and 9th-day post-infestation mangoes, non-infested ripe mangoes of three varieties (Kent, Apple, and Haden), and clean air (blank). We also compared the fruit fly's performance in the mango varieties and identified the chemical profiles of mango headspace volatiles. Ceratitis cosyra was attracted to both infested and non-infested mangoes (66-84 % of responsive C. cosyra) and showed superior performance in Kent mango (72.1 % of the 287 puparia recovered) compared to Apple and Haden varieties. Fopius arisanus displayed a stronger attraction to the volatiles of C. cosyra-infested mangoes (68-70 %), while P. cosyrae and D. longicaudata were significantly attracted to the 9th-day post-infestation mangoes (68-78 %) compared to non-infested mango volatiles. Gas chromatography-mass spectroscopy showed substantial quantitative and qualitative differences in volatile profiles among mango treatments. Esters predominated in non-infested ripe, 7th- and 9th-day post-infestation mangoes, while monoterpenes and sesquiterpenes were most dominant in the other treatments. The in situ experiments underscored varying preferences of the species for mango headspace volatiles and their subsequent treatments. These results provide valuable insights for further exploration, specifically in identifying the key volatiles responsible for species responses, to facilitate the development of applicable selective semiochemicals for managing species of African fruit fly.

4.
BMC Microbiol ; 24(1): 92, 2024 Mar 18.
Article in English | MEDLINE | ID: mdl-38500045

ABSTRACT

BACKGROUND: The soil biota consists of a complex assembly of microbial communities and other organisms that vary significantly across farming systems, impacting soil health and plant productivity. Despite its importance, there has been limited exploration of how different cropping systems influence soil and plant root microbiomes. In this study, we investigated soil physicochemical properties, along with soil and maize-root microbiomes, in an agroecological cereal-legume companion cropping system known as push-pull technology (PPT). This system has been used in agriculture for over two decades for insect-pest management, soil health improvement, and weed control in sub-Saharan Africa. We compared the results with those obtained from maize-monoculture (Mono) cropping system. RESULTS: The PPT cropping system changed the composition and diversity of soil and maize-root microbial communities, and led to notable improvements in soil physicochemical characteristics compared to that of the Mono cropping system. Distinct bacterial and fungal genera played a crucial role in influencing the variation in microbial diversity within these cropping systems. The relative abundance of fungal genera Trichoderma, Mortierella, and Bionectria and bacterial genera Streptomyces, RB41, and Nitrospira were more enriched in PPT. These microbial communities are associated with essential ecosystem services such as plant protection, decomposition, carbon utilization, bioinsecticides production, nitrogen fixation, nematode suppression, phytohormone production, and bioremediation. Conversely, pathogenic associated bacterial genus including Bryobacter were more enriched in Mono-root. Additionally, the Mono system exhibited a high relative abundance of fungal genera such as Gibberella, Neocosmospora, and Aspergillus, which are linked to plant diseases and food contamination. Significant differences were observed in the relative abundance of the inferred metabiome functional protein pathways including syringate degradation, L-methionine biosynthesis I, and inosine 5'-phosphate degradation. CONCLUSION: Push-pull cropping system positively influences soil and maize-root microbiomes and enhances soil physicochemical properties. This highlights its potential for agricultural and environmental sustainability. These findings contribute to our understanding of the diverse ecosystem services offered by this cropping system where it is practiced regarding the system's resilience and functional redundancy. Future research should focus on whether PPT affects the soil and maize-root microbial communities through the release of plant metabolites from the intercrop root exudates or through the alteration of the soil's nutritional status, which affects microbial enzymatic activities.


Subject(s)
Microbiota , Resilience, Psychological , Soil/chemistry , Zea mays , Fungi/genetics , Agriculture/methods , Bacteria/genetics , Soil Microbiology
5.
Sci Rep ; 14(1): 5045, 2024 02 29.
Article in English | MEDLINE | ID: mdl-38424443

ABSTRACT

The future of the food system on the planet is increasingly facing uncertainties that are attributable to population growth and a surge in demand for nutritious food. Traditional agricultural practices are poised to place strain on production, as well as natural resources and ecosystem services provided, particularly under a changing climate. Given their remarkable attributes, including a low environmental footprint, high food conversion ratio, rapid growth and nutritional values, edible insects can play a vital role in the global food system. Nonetheless, substantial knowledge gaps persist regarding their diversity, global distribution, and shared characteristics across regions, potentially impeding effective scaling and access to edible insects. Therefore, we compiled and analysed the fragmented database on edible insects and identified potential drivers that elucidate insect consumption, globally, focusing on promoting a sustainable food system. We collated data from various sources, including the literature for a list of edible insect species, the Global Biodiversity Information Facility and iNaturalist for the geographical presence of edible insects, the Copernicus Land Service library for Global Land Cover, and FAOSTAT for population, income, and nutritional security parameters. Subsequently, we performed a series of analytics at the country, regional and continental levels. Our study identifies 2205 insect species, consumed across 128 countries globally. Among continents, Asia has the highest number of edible insects (932 species), followed by North America (mainly Mexico) and Africa. The countries with the highest consumption of insects are Mexico (450 species), Thailand (272 species), India (262 species), DRC (255 species), China (235 species), Brazil (140 species), Japan (123 species), and Cameroon (100 species). Our study also revealed some common and specific practices related to edible insect access and utilisation among countries and regions. Although insect consumption is often rooted in cultural practices, it exhibits correlations with land cover, the geographical presence of potentially edible insects, the size of a country's population, and income levels. The practice of eating insects is linked to the culture of people in Africa, Asia, and Latin America, while increased consciousness and the need for food sustainability are driving most of the European countries to evaluate eating insects. Therefore, edible insects are becoming an increasingly significant part of the future of planetary food systems. Therefore, more proactive efforts are required to promote them for their effective contribution to achieving sustainable food production.


Subject(s)
Edible Insects , Animals , Humans , Ecosystem , Insecta , Allergens , Cameroon , Thailand
6.
Front Plant Sci ; 14: 1014865, 2023.
Article in English | MEDLINE | ID: mdl-37035056

ABSTRACT

The tomato leafminer, Tuta absoluta is a destructive invasive pest of cultivated tomato and other Solanaceae plants, with yield losses of 80-100%. Mirid predators are key natural enemies of T. absoluta, but they also feed on host plants in the absence of their prey. Management of T. absoluta is a challenge due to its high biotic potential, resistance to many insecticides and the absence of sufficiently adapted auxiliary fauna in its new dispersion zones. Olfaction plays an important role in the tritrophic interaction between tomato, its herbivore pest T. absoluta and its mirid predators, which can be influenced by non-host plant odors. However, how non-host odours shape this interaction is poorly understood. Previously, we had demonstrated belowground crop protection properties of certain Asteraceae plants against the root-knot nematode Meloidogyne incognita, pest of tomato and other Solanaceae plants. Additionally, Asteraceae plants impact negatively on feeding behavior of above-ground pests of Solanaceae plants, including the greenhouse whitefly (Trialeurodes vaporariorum) and green peach aphid (Myzus persicae). Here, we tested the hypothesis that foliar volatiles from some of these non-host Asteraceae plants can influence the tomato-T. absoluta-mirid predator tritrophic interaction. In olfactometer assays, T. absoluta females were attracted to volatiles of the Solanaceae host plants tomato and giant nightshade but avoided volatiles of the Asteraceae plants, blackjack and marigold, and the positive control, wild tomato, when tested alone or in combination with the host plants. Coupled gas chromatography-mass spectrometry analysis showed that host and non-host plants varied in their emission of volatiles, mainly monoterpenes and sesquiterpenes. Random forest analysis combined with behavioral assays identified monoterpenes as the host plant attractive blend to T. absoluta and its mirid predator, with sesquiterpenes identified as the non-host plant repellent blend against T. absoluta. Contrastingly, the mirid predator was indifferent to the non-host plant repellent sesquiterpenes. Our findings indicate that terpenes influence the tomato-T. absoluta-mirid predator tritrophic interaction. Further, our results emphasize the importance of studying crop protection from a holistic approach to identify companion crops that serve multi-functional roles.

7.
Ugeskr Laeger ; 184(44)2022 10 31.
Article in Danish | MEDLINE | ID: mdl-36331319

ABSTRACT

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is characterized by clinical evidence of myocardial infarction with normal or near-normal coronary arteries on angiography (less-than 50% stenosis). MINOCA is a group of heterogeneous diseases with different pathophysiologic mechanism which all can cause ischaemia. MINOCA is considered a "working diagnosis" after angiography until further evaluation regarding its underlying cause is made. The aim of this review is to assess the literature on clinical features, aetiology, diagnosis, treatment and prognosis of patients with MINOCA.


Subject(s)
Coronary Artery Disease , Myocardial Infarction , Humans , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/therapy , Coronary Angiography/adverse effects , Risk Factors , Myocardial Infarction/diagnosis , Myocardial Infarction/therapy , Coronary Vessels
8.
Front Public Health ; 10: 901414, 2022.
Article in English | MEDLINE | ID: mdl-36276393

ABSTRACT

Background: Snakebite is a major cause of mortality and morbidity in many areas, particularly in the rural tropics, and is a major public health problem around the world. It also imposes significant economic burdens on snakebite victims due to treatment-related expenses and lost productivity. Objective: The purpose of this study was to assess seasonal variation, treatment outcomes, and its associated factors among snakebite in Denan health center in the Somali region, Ethiopia. Method: A facility-based cross-sectional study was conducted from 10 to 30 September 2020 in Denan health center, Somali region, Ethiopia. All snakebite cases in Denan health center from 1 September 2015 to 31 August 2020 were included. Data were collected using a pre-tested structured checklist from the patient cards. Data were entered into EpiData version 3.1 and analyzed using SPSS version 22 (IBM SPSS Statistics, 2013). The prevalence was reported by proportion with 95% confidence interval (CI) and summary measures. Predictors were assessed using a multivariable logistic regression analysis model and reported using an adjusted odds ratio with 95% CI. Statistical significance was declared at p-value < 0. 05. Result: The overall prevalence of poor outcome of venomous snakebites was 31.4% (95% CI 26.3% 35.4%). Study participants with an age of less than 10 years old (AOR = 2.01; 95% CI 1.39, 4.05), age between 10 and 30 years old (AOR = 2.06; 95% CI 1.39, 9.30), arrival times greater than or equal to 6 hours (AOR = 2.37; 95% CI 1.39, 4.05), and timing of snakebite (AOR = 0.49; 95% CI 0.31-0.87) were factors found to be significantly associated with poor treatment outcome. Conclusion: According to this study, about one in every three snakebite patients have a poor outcome. Patients with poor outcomes were those who did not improve as a result of treatment or died as a result of it. Designing appropriate engagement of public health education about snakebite prevention techniques, particularly during entry and exit of rainy seasons and establishment of appropriate case management protocol is strongly recommended, as well as increasing the accessibility or availability of antivenoms will undoubtedly have a significant impact on the reduction of mortality and disability related to that of the snakebites.


Subject(s)
Snake Bites , Humans , Snake Bites/epidemiology , Snake Bites/therapy , Cross-Sectional Studies , Seasons , Antivenins/therapeutic use , Ethiopia/epidemiology , Somalia , Treatment Outcome
9.
Endocrine ; 78(3): 418-428, 2022 12.
Article in English | MEDLINE | ID: mdl-36018537

ABSTRACT

PURPOSE: This study aims to review all published cases on the association between thyrotoxicosis and Takutsubo Syndrome by describing clinical characteristics, diagnostic work-up, treatment, and outcome. METHODS: We searched PubMed and Embase databases from inception to the 17th of February 2022 for case reports or series reporting the above-mentioned association. We extracted data on demographic characteristics, clinical features, diagnostic work-up, treatment, and clinical outcomes. Cases were stratified into groups based on the presumed cause of the thyrotoxicosis (iatrogenic vs non-iatrogenic and Graves' diseases vs non-Graves' disease, respectively). RESULTS: We identified 25 cases from 24 articles. The mean age was 61.7 years (+/- SD 14.5). Most patients were women (88%). Graves' disease (52%) was the leading cause of thyrotoxicosis. Previous cancer was significantly more common in patients with iatrogenic thyrotoxicosis (P = 0.03). The most common symptoms were respiratory symptoms (68%), chest pain (56%), and palpitations (40%). The most common ECG characteristics were T-wave abnormalities (48%) and ST-elevations (36%). Elevated troponin levels were found in 92% of the cases. Patients with Graves's disease and Takutsubo Syndrome had higher plasma levels of serum thyroxine (P = 0.03) and were more often treated with beta-blockers (P = 0.01) compared to patients with thyrotoxicosis of other origins. Notably, 40% of cases experienced in-hospital complications. No deaths were reported. All patients had improved cardiac function within a median follow-up of 42 days. CONCLUSION: Evidence-based on current case reports suggests an increased risk of Takutsubo Syndrome and subsequently increased risk of in-hospital complications in patients with thyrotoxicosis.


Subject(s)
Graves Disease , Takotsubo Cardiomyopathy , Thyrotoxicosis , Humans , Female , Middle Aged , Male , Takotsubo Cardiomyopathy/etiology , Thyrotoxicosis/complications , Thyrotoxicosis/epidemiology , Graves Disease/diagnosis
10.
Ugeskr Laeger ; 183(49)2021 12 06.
Article in Danish | MEDLINE | ID: mdl-34895438

ABSTRACT

For decades, diuretics have been the cornerstone in the treatment of patients with chronic heart failure with reduced ejection fraction (HFrEF) presenting with congestion. However, evidence guiding the use of diuretics is generally lacking. Adequate dosing and evaluation of diuretic effect are important for treatment success. Measuring the concentration of sodium in urine in addition to urinary output has been suggested as a good marker to guide the use of diuretics. This review summaries the current knowledge on the use of diuretics in patients with HFrEF presenting with congestion.


Subject(s)
Heart Failure , Ventricular Dysfunction, Left , Diuretics/therapeutic use , Heart Failure/drug therapy , Humans , Sodium , Stroke Volume
11.
Ugeskr Laeger ; 183(49)2021 12 06.
Article in Danish | MEDLINE | ID: mdl-34895440

ABSTRACT

Rapid identification of acute myocardial infarction (MI) is important for the early initiation of evidence-based therapy. In the European Society of Cardiology (ESC) 0/1h-algorithm (also called early-rule-out algorithm) high-sentivity cardiac troponin is measured at admission and one hour later. By using assay-specific cut-off levels patients are triaged to three different groups; "rule-out", "observation" or "rule-in" of acute MI. The ESC 0/1h-algorithm has high diagnostic accuracy and safety to rule out MI. This review summaries the current knowledge and practical use of the new early-rule-out algorithm.


Subject(s)
Cardiovascular System , Myocardial Infarction , Algorithms , Biomarkers , Humans , Myocardial Infarction/diagnosis , Prospective Studies , Triage , Troponin T
12.
JMIR Public Health Surveill ; 6(4): e18950, 2020 12 02.
Article in English | MEDLINE | ID: mdl-33263550

ABSTRACT

BACKGROUND: As we move toward a polio-free world, the challenge for the polio program is to create an unrelenting focus on smaller areas where the virus is still present, where children are being repeatedly missed, where immunity levels are low, and where surveillance is weak. OBJECTIVE: This article aimed to describe a possible solution to address weak surveillance systems and document the outcomes of the deployment of the Auto-Visual Acute Flaccid Paralysis Detection and Reporting (AVADAR) project. METHODS: This intervention was implemented in 99 targeted high-risk districts with concerns for silent polio circulation from eight countries in Africa between August 1, 2017, and July 31, 2018. A total of 6954 persons (5390 community informants and 1564 health workers) were trained and equipped with a smartphone on which the AVADAR app was configured to allow community informants to send alerts on suspected acute flaccid paralysis (AFP) and allow health worker to use electronic checklists for investigation of such alerts. The AVADAR and Open Data Kit ONA servers were at the center of the entire process. A dashboard system and coordination teams for monitoring and supervision were put in place at all levels. RESULTS: Overall, 96.44% (24,142/25,032) of potential AFP case alerts were investigated by surveillance personnel, yielding 1414 true AFP cases. This number (n=1414) reported through AVADAR was higher than the 238 AFP cases expected during the study period in the AVADAR districts and the 491 true AFP cases reported by the traditional surveillance system. A total of 203 out of the 1414 true AFP cases reported were from special population settings, such as refugee camps and insecure areas. There was an improvement in reporting in silent health areas in all the countries using the AVADAR system. Finally, there were 23,473 reports for other diseases, such as measles, diarrhea, and cerebrospinal meningitis, using the AVADAR platform. CONCLUSIONS: This article demonstrates the added value of AVADAR to rapidly improve surveillance sensitivity. AVADAR is capable of supporting countries to improve surveillance sensitivity within a short interval before and beyond polio-free certification.


Subject(s)
Muscle Hypotonia/diagnosis , Poliomyelitis/prevention & control , Population Surveillance/methods , Africa/epidemiology , Evaluation Studies as Topic , Humans , Mass Screening/methods , Mass Screening/statistics & numerical data , Muscle Hypotonia/epidemiology , Poliomyelitis/epidemiology , Program Evaluation/methods
13.
RSC Adv ; 9(58): 34039-34049, 2019 Oct 18.
Article in English | MEDLINE | ID: mdl-35528904

ABSTRACT

Eucalyptol is the natural cyclic ether which constitutes the bulk of terpenoids found in essential oils of Eucalyptus spp. and is used in aromatherapy for treatment of migraine, sinusitis, asthma and stress. It acts by inhibiting arachidonic acid metabolism and cytokine production. Chemical instability and volatility of eucalyptol restrict its therapeutic application and necessitate the need to develop an appropriate delivery system to achieve extended release and enhance its bioactivity. However, the synthesis method of the delivery system must be suitable to prevent loss or inactivation of the drug during processing. In this study, supercritical carbon dioxide (scCO2) was explored as an alternative solvent for encapsulation and co-precipitation of eucalyptol with polyethylene glycol (PEG) and/or polycaprolactone (PCL) using the particles from gas-saturated solution (PGSS) process. Polymers and eucalyptol were pre-mixed and then processed in a PGSS autoclave at 45 °C and 80 bar for 1 h. The mixture in scCO2 was micronized and characterized. The presence of eucalyptol in the precipitated particles was confirmed by infrared spectroscopy, gas chromatography and mass spectrometry. The weight ratios of PEG-PCL blends significantly influenced loading capacity and encapsulation efficiency with 77% of eucalyptol encapsulated in a 4 : 1 composite blend of PEG-PCL. The particle size distribution of the PGSS-micronized particles ranged from 30 to 260 µm. ScCO2 assisted microencapsulation in PEG and PCL reduced loss of the volatile drug during a two-hour vaporization study and addition of PCL extended the mean release time in simulated physiological fluids. Free radical scavenging and lipoxygenase inhibitory activities of eucalyptol formulated in the PGSS-micronized particles was sustained. Findings from this study showed that the scCO2-assisted micronization can be used for encapsulation of volatile drugs in polymeric microparticles without affecting bioactivity of the drug.

14.
J Insect Sci ; 14: 53, 2014 Apr 19.
Article in English | MEDLINE | ID: mdl-25373200

ABSTRACT

The African termiteraiding ant Pachycondyla analis Latreille (Hymenoptera: Formicidae) organizes group raids on termites of the subfamily Macrotermitinae. Termites and ants occupy and share similar habitats, resulting in a co-evolutionary arms race between termites as prey and ants as predators. The present study explored whether P. analis uses semio- chemical signaling cues to detect potential termite prey prior to and during raids. Ants' responses to odors emitted from termites alone, termite gallery soil, and termites inside their galleries were tested using Y-tube olfactometer assays. The results showed that P. analis detected odors of termites and those of their galleries, and odors from termites inside their galleries were more attractive to both minor and major ant workers than odors from termites alone. The composition of these odor sources was identified using gas chromatography-mass spectrometry analysis. While the odors from termite gallery soils were compositionally richer (containing 13 compounds rather than nine from termites alone), those from the termites alone were quantitatively richer, releasing about six times more odors than gallery soil. Most of the compounds in the odor profiles were identified as hydrocarbons. Naphthalene, previously identified as an insect repellent, was also identified as a component of the odors from the gallery soil. These results demonstrate that odors play an important role in prey detection by P. analis.


Subject(s)
Ants/physiology , Isoptera/physiology , Odorants , Predatory Behavior , Animals , Biological Assay , Female , Gas Chromatography-Mass Spectrometry , Male
15.
AIDS Res Hum Retroviruses ; 26(10): 1051-61, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20849299

ABSTRACT

Serological assays for estimating HIV-1 incidence are prone to misclassification, limiting the accuracy of the incidence estimate. Adjustment factors have been developed and recommended for estimating assay-based HIV-1 incidence in cross-sectional settings. We evaluated the performance of the recommended adjustment factors for estimating incidence in national HIV surveys in three countries in sub-Saharan Africa. The BED-capture enzyme immunoassay was applied to stored blood specimens from (1) pregnant women aged 15-49 years attending antenatal clinics in Côte d'Ivoire (1998-2004), (2) adults aged 15-49 years participating in a demographic health survey in Kenya (2003), and (3) adults aged 15-49 years participating in a national household serosurvey in South Africa (2005). Assay-derived incidence estimates were corrected for misclassification using recommended adjustment factors and, where possible, were compared to mathematically modeled incidence in the same populations. Trends in HIV prevalence were compared to trends in assay-derived incidence to assess plausibility in the assay-derived trends. Unadjusted incidence was 3.8% [95% confidence interval (CI) 3.3-4.5] in Côte d'Ivoire, 3.5% (2.7-4.3) in Kenya, and 4.4% (CI 2.3-6.5]) in South Africa. Adjusted incidence was 2.9% (CI 2.1-3.7) in Côte d'Ivoire, 2.6% (CI 2.0-3.2) in Kenya, and 2.4% (CI 1.7-3.1) in South Africa. After adjustment, peak incidence shifted from older to younger age groups in Côte d'Ivoire and South Africa. Modeled HIV incidence was 1.0% (CI 1.02-1.08) in Kenya and 2.0% (CI 1.7-2.4) in South Africa. After applying the recommended adjustments factors, adjusted assay-derived estimates remained implausibly high in two of three populations evaluated. For more accurate measures of assay-derived population incidence, adjustment factors must be locally derived and validated. Until improved assays are available, caution should be applied in the use and interpretation of data from incidence assays.


Subject(s)
AIDS Serodiagnosis , HIV Infections/epidemiology , HIV Seroprevalence/trends , Population Surveillance , Pregnancy Complications, Infectious/epidemiology , Adolescent , Adult , Cote d'Ivoire/epidemiology , Cross-Sectional Studies , Female , Humans , Immunoenzyme Techniques , Kenya/epidemiology , Male , Middle Aged , Models, Theoretical , Pregnancy , Pregnancy Complications, Infectious/virology , Prevalence , South Africa/epidemiology , Young Adult
16.
Trop Med Int Health ; 14(10): 1215-9, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19708898

ABSTRACT

OBJECTIVE: To determine the role of participant factors on the acceptance of a Prevention-of-Mother-to-Child (PMTCT) HIV test programme in a situation with an opt-out testing strategy. METHODS: We analysed antenatal clinic (ANC) HIV sentinel surveillance data. All 43 sites in the 2005 round of Kenya's ANC surveillance offered opt-out PMTCT services and recorded if women were offered PMTCT HIV testing and whether they accepted or refused. Logistic regression was used to determine the role of participant-level factors on PMTCT acceptance. RESULTS: During the period of sentinel surveillance, 13,026 women attended ANC and testing was offered to 12,030 women. Of those offered testing, 9690 (80.5%) accepted, with a large variation in the percent of acceptors by site. Age, residence and educational status were significant determinants of PMTCT acceptance. However, after adjusting for site none of the participant-level factors were significant determinants of PMTCT acceptance. CONCLUSIONS: Participant level factors were not significant determinants of PMTCT HIV test acceptance after adjusting for sites. PMTCT programmes should collect and evaluate the role of site-level (provider and testing service) factors on PMTCT acceptance. Improvement of site-level factors could improve PMTCT uptake.


Subject(s)
AIDS Serodiagnosis/statistics & numerical data , HIV Infections/transmission , HIV-1 , Health Services Accessibility/standards , Infectious Disease Transmission, Vertical/prevention & control , Patient Acceptance of Health Care/statistics & numerical data , Prenatal Care/standards , Adolescent , Adult , Female , Humans , Kenya , Logistic Models , Middle Aged , Population Surveillance , Pregnancy , Young Adult
17.
Am J Obstet Gynecol ; 197(3 Suppl): S17-25, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17825646

ABSTRACT

Prevention of mother-to-child human immunodeficiency virus (HIV) transmission (PMTCT) programs are expanding in resource-limited countries and are increasingly implemented in antenatal clinics (ANC) in which HIV sentinel surveillance is conducted. ANC sentinel surveillance data can be used to evaluate the first visit of a pregnant woman to PMTCT programs. We analyzed data from Kenya and Ethiopia, where information on PMTCT test acceptance was collected on the 2005 ANC sentinel surveillance forms. For Zimbabwe, we compared the 2005 ANC sentinel surveillance data to the PMTCT program data. ANC surveillance data allowed us to calculate the number of HIV-positive women not participating in the PMTCT program. The percentage of HIV-positive women missed by the PMTCT program was 17% in Kenya, 57% Ethiopia, and 59% Zimbabwe. The HIV prevalence among women participating in PMTCT differed from women who did not. ANC sentinel surveillance can be used to evaluate and improve the first encounter in PMTCT programs. Countries should collect PMTCT-related program data through ANC surveillance to strengthen the PMTCT program.


Subject(s)
Acquired Immunodeficiency Syndrome/transmission , Developing Countries , Health Resources/supply & distribution , Infectious Disease Transmission, Vertical/prevention & control , Pregnancy Complications, Infectious , Sentinel Surveillance , Acquired Immunodeficiency Syndrome/epidemiology , Acquired Immunodeficiency Syndrome/prevention & control , Ethiopia/epidemiology , Female , Humans , Kenya/epidemiology , Pregnancy , Pregnancy Complications, Infectious/epidemiology , Prevalence , Zimbabwe/epidemiology
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