Synthetic PET from CT improves diagnosis and prognosis for lung cancer: Proof of concept

[18F]Fluorodeoxyglucose positron emission tomography (FDG-PET) and computed tomography (CT) are indispensable components in modern medicine. Although PET can provide additional diagnostic value, it is costly and not universally accessible, particularly in low-income countries. To bridge this gap, we have developed a conditional generative adversarial network pipeline that can produce FDG-PET from diagnostic CT scans based on multi-center multi-modal lung cancer datasets (n = 1,478). Synthetic PET images are validated across imaging, biological, and clinical aspects. Radiologists confirm comparable imaging quality and tumor contrast between synthetic and actual PET scans. Radiogenomics analysis further proves that the dysregulated cancer hallmark pathways of synthetic PET are consistent with actual PET. We also demonstrate the clinical values of synthetic PET in improving lung cancer diagnosis, staging, risk prediction, and prognosis. Taken together, this proof-of-concept study testifies to the feasibility of applying deep learning to obtain high-fidelity PET translated from CT.

Probing the p-type Chemiresistive Response of NiFe2 O4 Nanoparticles for Potential Utilization as Ethanol Sensor

Detection of gas molecules and volatile organic compounds (VOCs) using efficient, low cost sensors has fetched significant attention in environmental monitoring, safety measures and medical diagnosis. In the present work, nickel ferrite (NFO) nanoparticles are explored as p-type semiconducting metal oxide (SMO) sensor for detection of five different organic vapors namely methanol, ethanol, n-propanol, iso-propanol and acetone which often cause severe damage to human body under prolonged exposure. The sensing studies in presence of the aforementioned five vapors are carried out by varying the sensor operating temperature (225-300 °C) and vapor concentrations (10-1000 ppm). Developed NFO sensor demonstrated best performance in terms of sensing (~10 ppm), response time (<10 s), excellent repeatability and selectivity towards ethanol among all other considered gas species. The repeatability of the sensor response is verified and the underlying reasons for the variation in the response of NFO sensor due to the change of operating temperature, analyte type and concentrations has been discussed. The synthesis of NFO through auto combustion method and study on their formation behaviour, oxygen vacancy evolution, band gap calculation, crystalline nature as well as microstructural features provides here the comprehensive information about the potential application of NFO nanoparticles as gas sensor.

Automated Cellular-Level Dual Global Fusion of Whole-Slide Imaging for Lung Adenocarcinoma Prognosis

Histopathologic whole-slide images (WSI) are generally considered the gold standard for cancer diagnosis and prognosis. Survival prediction based on WSI has recently attracted substantial attention. Nevertheless, it remains a central challenge owing to the inherent difficulties of predicting patient prognosis and effectively extracting informative survival-specific representations from WSI with highly compounded gigapixels. In this study, we present a fully automated cellular-level dual global fusion pipeline for survival prediction. Specifically, the proposed method first describes the composition of different cell populations on WSI. Then, it generates dimension-reduced WSI-embedded maps, allowing for efficient investigation of the tumor microenvironment. In addition, we introduce a novel dual global fusion network to incorporate global and inter-patch features of cell distribution, which enables the sufficient fusion of different types and locations of cells. We further validate the proposed pipeline using The Cancer Genome Atlas lung adenocarcinoma dataset. Our model achieves a C-index of 0.675 (±0.05) in the five-fold cross-validation setting and surpasses comparable methods. Further, we extensively analyze embedded map features and survival probabilities. These experimental results manifest the potential of our proposed pipeline for applications using WSI in lung adenocarcinoma and other malignancies.

Performance of testers with contrasting provitamin A content to evaluate provitamin A maize for resistance to Aspergillus flavus infection and aflatoxin production

In sub-Saharan Africa (SSA), millions of people depend on maize as a primary staple. However, maize consumers in SSA may be exposed to malnutrition due to vitamin A deficiency (VAD) and unsafe aflatoxin levels, which can lead to serious economic and public health problems. Provitamin A (PVA) biofortified maize has been developed to alleviate VAD and may have additional benefits such as reduced aflatoxin contamination. In this study, maize inbred testers with contrasting PVA content in grain were used to identify inbred lines with desirable combining ability for breeding to enhance their level of resistance to aflatoxin. Kernels of 120 PVA hybrids generated by crossing 60 PVA inbreds with varying levels of PVA (5.4 to 51.7 µg/g) and two testers (low and high PVA, 14.4 and 25.0 µg/g, respectively) were inoculated with a highly toxigenic strain of Aspergillus flavus. Aflatoxin had a negative genetic correlation with β-carotene (r = -0.29, p < 0.0001) and PVA (r = -0.23, p < 0.0001), indicating that hybrids with high PVA content accumulated less aflatoxin than those with low to medium PVA. Both general combining ability (GCA) and specific combining ability (SCA) effects of lines and testers were significant for aflatoxin accumulation, number of spores, PVA, and other carotenoids, with additive gene actions playing a prominent role in regulating the mode of inheritance (GCA/SCA ratio >0.5). Eight inbreds had combined significant negative GCA effects for aflatoxin accumulation and spore count with significant positive GCA effects for PVA. Five testcrosses had combined significant negative SCA effects for aflatoxin with significant positive SCA effects for PVA. The high PVA tester had significant negative GCA effects for aflatoxin, lutein, β-carotene, and PVA. The study identified lines that can be used as parents to develop superior hybrids with high PVA and reduced aflatoxin accumulation. Overall, the results point out the importance of testers in maize breeding programs to develop materials that can contribute to controlling aflatoxin contamination and reducing VAD.

Aflatoxin biocontrol effectiveness in the real world—Private sector-led efforts to manage aflatoxins in Nigeria through biocontrol-centered strategies

Aflatoxins are toxic compounds produced by several Aspergillus species that contaminate various crops. The impact of aflatoxin on the health of humans and livestock is a concern across the globe. Income, trade, and development sectors are affected as well. There are several technologies to prevent aflatoxin contamination but there are difficulties in having farmers use them. In Nigeria, an aflatoxin biocontrol product containing atoxigenic isolates of A. flavus has been registered with regulatory authorities and is now being produced at scale by the private company Harvestfield Industries Limited (HIL). The current study reports results of biocontrol effectiveness trials in maize conducted by HIL during 2020 in several locations across Nigeria and compared to untreated maize from nearby locations. Also, maize was collected from open markets to assess levels of contamination. All treated maize met tolerance thresholds (i.e., &lt;4 ppb total aflatoxin). In contrast, most maize from untreated fields had a higher risk of aflatoxin contamination, with some areas averaging 38.5 ppb total aflatoxin. Maize from open markets had aflatoxin above tolerance thresholds with even an average of up to 90.3 ppb. Results from the trials were presented in a National Workshop attended by key officers of Government agencies, farmer organizations, the private sector, NGOs, and donors. Overall, we report (i) efforts spearheaded by the private sector to have aflatoxin management strategies used at scale in Nigeria, and (ii) deliberations of key stakeholders to ensure the safety of crops produced in Nigeria for the benefit of farmers, consumers, and industries.

Atoxigenic-based technology for biocontrol of aflatoxin in maize and groundnuts for Tanzania

Application of biocontrol products containing atoxigenic isolates of Aspergillus flavus to reduce aflatoxin content in crops is an effective strategy for managing aflatoxin in several regions throughout the world. We report the development and validation of two aflatoxin biocontrol products, Aflasafe TZ01 and Aflasafe TZ02, for use in maize and groundnut in Tanzania, a country frequently affected by aflatoxin contamination. Each product contains four atoxigenic A. flavus genotypes native and widely distributed in Tanzania. Efficacy tests on maize and groundnut were conducted over two years and in four regions of Tanzania where aflatoxin contamination is prevalent. Application of both products significantly (P<0.05) reduced aflatoxin levels in maize and groundnut in both years and in all districts. No differences were observed in total Aspergillus section Flavi population in treated and untreated fields, revealing that application of the biocontrol products do not alter overall Aspergillus populations in the environment. The results indicate that both products are effective tools for aflatoxin mitigation in groundnut and maize. The products were officially registered in 2018. Currently, there are scale-out and-up efforts of aflatoxin biocontrol products in Tanzania through a private sector company that is making the products available to farmers. Protecting maize and groundnut from aflatoxin contamination in Tanzania can result in health, income, and trade benefits.

A Study to Measure Sexual Dysfunction among Women of Reproductive Age Group with Diabetes Mellitus Attending the Outpatient Department of a Tertiary Care Hospital in Kolkata

Sexual dysfunction in Diabetes is an under-investigated problem, especially in women. The research barriers surrounding the issue of female sexual dysfunction are manifold and difficult to surpass, especially in the context of the Asian Subcontinent, where a multitude of sociocultural factors suppress the expression of distress. Early screening, diagnosis, and counselling can help in managing female sexual dysfunction in Diabetes Mellitus and positively impact the lives of many women. This study was undertaken to find the prevalence of sexual dysfunction among diabetic women of reproductive age group, its relation to BMI, duration of Diabetes and microvascular complications, and to find its sociodemographic associations.

MATERIAL

A descriptive, observational study was carried out over a period of 1 year. 250 purposively sampled women attending the diabetic outpatient department of a tertiary care hospital were enrolled. All were known diabetic, between the ages of 30 and 44 years. A detailed history was obtained with the aid of a case record form which included the FSFI (Female Sexual Function Index), and a demographic questionnaire, after proper explanation in their own local vernacular as per their literacy level. Available medical records were used for finding the duration of diabetes, and associated diabetes related microvascular complications.

OBSERVATION

Prevalence of FSD among the study population was 73.6%. A significant association was found between age and sexual dysfunction (p&lt;0.05). It was found to be more among the Hindus, compared to the Muslims (p&lt;0.05). There was a significant association with BMI (&gt;25kg/m2), increasing duration of Diabetes, and the presence of microvascular complications (p&lt;0.05). In fact, all patients with microvascular complications were experiencing some degree of sexual dysfunction. No association was found with socioeconomic status, literacy, addiction, occupation or type of family.

CONCLUSION

Female sexual health issues in Diabetes are a neglected area, both in the clinic as well as in research, yet sexual health problems in this group may be more common than previously recognised. Low FSFI scores are associated with increasing age, higher BMI and increasing duration of Diabetes. Future studies may identify appropriate ways to probe and explore the related issues for early screening, and help establish the role of newer treatments.

Aflatoxin contamination in Tanzania: quantifying the problem in maize and groundnuts from rural households

Aflatoxins are toxic and carcinogenic secondary metabolites, produced by Aspergillus flavus and Aspergillus parasiticus, which contaminate food and feed and threaten human and animal health. To assess the prevalence of aflatoxins in Tanzania, 180 groundnut and 200 maize samples were collected from 9 and 10 districts, respectively. Aflatoxin contamination was quantified using high performance liquid chromatography. Aflatoxins were detected in samples collected from all districts and prevalence ranged from 92 to 100% for groundnuts and 10 to 80% for maize. The mean aflatoxin level for groundnuts was 6.37 μg/kg and the highly contaminated sample had 40.31 μg/kg. For maize, the mean aflatoxin level was 12.47 μg/kg and the highly contaminated sample had 162.40 μg/kg. The estimated average probable daily intake (APDI) of aflatoxin B1 (AFB1) from groundnuts consumption was 1.88 ng/kg body weight/day, while for maize, it ranged between 151.98-272.89 ng/kg body weight/day. The APDI for both groundnut and maize exceeded the provisional maximum tolerable daily intake (PMTDI) of AFB1 for adults (1 ng/kg body weight/day), bringing about health concerns for populations in Tanzania. Another alarming finding was that 75% of the farmers who provided samples for analysis were not aware of aflatoxins or the negative health impacts from consuming contaminated products. Results reported in this paper show that aflatoxin contaminated staple crops are widely distributed in Tanzania and that the risk of human exposure is high due to diet preferences. Awareness campaigns are required to inform and protect farmers and consumers.

Aflasafe SN01 is the First Biocontrol Product Approved for Aflatoxin Mitigation in Two Nations, Senegal and The Gambia

Aflatoxin contamination is caused by Aspergillus flavus and closely related fungi. In The Gambia, aflatoxin contamination of groundnut and maize, two staple and economically important crops, is common. Groundnut and maize consumers are chronically exposed to aflatoxins, sometimes at alarming levels, and this has severe consequences on their health and productivity. Aflatoxin contamination also impedes commercialization in local and international premium markets. In neighboring Senegal, an aflatoxin biocontrol product containing four atoxigenic isolates of A. flavus, Aflasafe SN01, has been registered and is approved for commercial use in groundnut and maize. We detected that the four genotypes composing Aflasafe SN01 are also native to The Gambia. The biocontrol product was tested during two years in 129 maize and groundnut fields and compared with corresponding untreated fields cropped by smallholder farmers in The Gambia. Treated crops contained up to 100% less aflatoxins than untreated crops. A large portion of the crops could have been commercialized in premium markets due to the low aflatoxin content (in many cases no detectable aflatoxins), both at harvest and after storage. Substantial aflatoxin reductions were also achieved when commercially produced groundnut received treatment. Here we report for the first time the use and effectiveness of an aflatoxin biocontrol product registered for use in two nations. With the current scale-out and -up efforts of Aflasafe SN01, a large number of farmers, consumers, and traders in The Gambia and Senegal will obtain health, income, and trade benefits.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.

The Atoxigenic Biocontrol Product Aflasafe SN01 Is a Valuable Tool to Mitigate Aflatoxin Contamination of Both Maize and Groundnut Cultivated in Senegal

Aflatoxin contamination of groundnut and maize infected by Aspergillus section Flavi fungi is common throughout Senegal. The use of biocontrol products containing atoxigenic Aspergillus flavus strains to reduce crop aflatoxin content has been successful in several regions, but no such products are available in Senegal. The biocontrol product Aflasafe SN01 was developed for use in Senegal. The four active ingredients of Aflasafe SN01 are atoxigenic A. flavus genotypes native to Senegal and distinct from active ingredients used in other biocontrol products. Efficacy tests on groundnut and maize in farmers' fields were carried out in Senegal during the course of 5 years. Active ingredients were monitored with vegetative compatibility analyses. Significant (P < 0.05) displacement of aflatoxin producers occurred in all years, districts, and crops. In addition, crops from Aflasafe SN01-treated fields contained significantly (P < 0.05) fewer aflatoxins both at harvest and after storage. Most crops from treated fields contained aflatoxin concentrations permissible in both local and international markets. Results suggest that Aflasafe SN01 is an effective tool for aflatoxin mitigation in groundnut and maize. Large-scale use of Aflasafe SN01 should provide health, trade, and economic benefits for Senegal.[Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.

Prevalence and mitigation of aflatoxins in Kenya (1960-to date)

Aflatoxins are highly toxic metabolites of several Aspergillus species widely distributed throughout the environment. These toxins have adverse effects on humans and livestock at a few micrograms per kilogram (μg/kg) concentrations. Strict regulations on the concentrations of aflatoxins allowed in food and feed exist in many nations in the developing world. Loopholes in implementing regulations result in the consumption of dangerous concentrations of aflatoxins. In Kenya, where 'farm-to-mouth' crops become severely contaminated, solutions to the aflatoxins problem are needed. Across the decades, aflatoxins have repeatedly caused loss of human and animal life. A prerequisite to developing viable solutions for managing aflatoxins is understanding the geographical distribution and severity of food and feed contamination, and the impact on lives. This review discusses the scope of the aflatoxins problem and management efforts by various players in Kenya. Economic drivers likely to influence the choice of aflatoxins management options include historical adverse health effects on humans and animals, cost of intervention for mitigation of aflatoxins, knowledge about aflatoxins and their impact, incentives for aflatoxins safe food and intended scope of use of interventions. It also highlights knowledge gaps that can direct future management efforts. These include: sparse documented information on human exposure; few robust tools to accurately measure economic impact in widely unstructured value chains; lack of long-term impact studies on benefits of aflatoxins mitigation; inadequate sampling mechanisms in smallholder farms and grain holding stores/containers; overlooking social learning networks in technology uptake and lack of in-depth studies on an array of aflatoxins control measures followed in households. The review proposes improved linkages between agriculture, nutrition and health sectors to address aflatoxins contamination better. Sustained public awareness at all levels, capacity building and aflatoxins related policies are necessary to support management initiatives.

Prevalence of Aflatoxin Contamination in Maize and Groundnut in Ghana: Population Structure, Distribution, and Toxigenicity of the Causal Agents

Aflatoxin contamination in maize and groundnut is perennial in Ghana with substantial health and economic burden on the population. The present study examined for the first time the prevalence of aflatoxin contamination in maize and groundnut in major producing regions across three agroecological zones (AEZs) in Ghana. Furthermore, the distribution and aflatoxin-producing potential of Aspergillus species associated with both crops were studied. Out of 509 samples (326 of maize and 183 of groundnut), 35% had detectable levels of aflatoxins. Over 15% of maize and 11% of groundnut samples exceeded the aflatoxin threshold limits set by the Ghana Standards Authority of 15 and 20 ppb, respectively. Mycoflora analyses revealed various species and morphotypes within the Aspergillus section Flavi. A total of 5,083 isolates were recovered from both crops. The L morphotype of Aspergillus flavus dominated communities with 93.3% of the population, followed by Aspergillus spp. with S morphotype (6%), A. tamarii (0.4%), and A. parasiticus (0.3%). Within the L morphotype, the proportion of toxigenic members was significantly (P < 0.05) higher than that of atoxigenic members across AEZs. Observed and potential aflatoxin concentrations indicate that on-field aflatoxin management strategies need to be implemented throughout Ghana. The recovered atoxigenic L morphotype fungi are genetic resources that can be employed as biocontrol agents to limit aflatoxin contamination of maize and groundnut in Ghana. Copyright © 2018 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .

Aflatoxin awareness and Aflasafe adoption potential of Nigerian smallholder maize farmers: OPEN ACCESS

Aflatoxin is a potent mycotoxin that can cause cancer and death and is associated with stunted growth. Prevalence of aflatoxin is widespread in Africa negatively impacting health and trade. Aflasafe is a biological control product that can be applied to maize or groundnut fields to reduce aflatoxin contamination. This study examines the levels of aflatoxin and Aflasafe awareness and understanding among smallholder maize farmers in Nigeria. In addition, the factors affecting Aflasafe purchase patterns and sustained usage over multiple growing seasons by farmers were evaluated. In-person surveys of 902 Nigerian smallholder farmers were conducted during October and November of 2016. This work contributes to the existing literature by documenting awareness levels of aflatoxin and use of Aflasafe as a control in Nigeria. Results suggest that the level of awareness of aflatoxin was very high in states where Aflasafe was promoted as an intervention for aflatoxin management. In Kaduna state, the region with the longest intervention, there was a consistent increase in the usage of Aflasafe since its introduction in 2010. Furthermore, farmers who purchase Aflasafe bundled (combined) with other inputs were more likely to persist in using the product. Education was found to significantly and positively impact continued usage of Aflasafe. Continued interventions, promotion and general education of the public are recommended for increased awareness, trial, and adoption of Aflasafe in Nigeria.

Aflatoxin contamination of groundnut and maize in Zambia: observed and potential concentrations

AIMS

The aims of the study were to quantify aflatoxins, the potent carcinogens associated with stunting and immune suppression, in maize and groundnut across Zambia's three agroecologies and to determine the vulnerability to aflatoxin increases after purchase.

METHODS AND RESULTS

Aflatoxin concentrations were determined for 334 maize and groundnut samples from 27 districts using lateral-flow immunochromatography. Seventeen per cent of crops from markets contained aflatoxin concentrations above allowable levels in Zambia (10 μg kg-1 ). Proportions of crops unsafe for human consumption differed significantly (P < 0·001) among agroecologies with more contamination (38%) in the warmest (Agroecology I) and the least (8%) in cool, wet Agroecology III. Aflatoxin in groundnut (39 μg kg-1 ) and maize (16 μg kg-1 ) differed (P = 0·032). Poor storage (31°C, 100% RH, 1 week) increased aflatoxin in safe crops by over 1000-fold in both maize and groundnut. The L morphotype of Aspergillus flavus was negatively correlated with postharvest increases in groundnut.

CONCLUSIONS

Aflatoxins are common in Zambia's food staples with proportions of unsafe crops dependent on agroecology. Fungal community structure influences contamination suggesting Zambia would benefit from biocontrol with atoxigenic A. flavus.

SIGNIFICANCE AND IMPACT OF THE STUDY

Aflatoxin contamination across the three agroecologies of Zambia is detailed and the case for aflatoxin management with atoxigenic biocontrol agents provided. The first method for evaluating the potential for aflatoxin increase after purchase is presented.

Biological control of aflatoxins in Africa: current status and potential challenges in the face of climate change

Aflatoxin contamination of crops is frequent in warm regions across the globe, including large areas in sub-Saharan Africa. Crop contamination with these dangerous toxins transcends health, food security, and trade sectors. It cuts across the value chain, affecting farmers, traders, markets, and finally consumers. Diverse fungi within Aspergillus section Flavi contaminate crops with aflatoxins. Within these Aspergillus communities, several genotypes are not capable of producing aflatoxins (atoxigenic). Carefully selected atoxigenic genotypes in biological control (biocontrol) formulations efficiently reduce aflatoxin contamination of crops when applied prior to flowering in the field. This safe and environmentally friendly, effective technology was pioneered in the US, where well over a million acres of susceptible crops are treated annually. The technology has been improved for use in sub-Saharan Africa, where efforts are under way to develop biocontrol products, under the trade name Aflasafe, for 11 African nations. The number of participating nations is expected to increase. In parallel, state of the art technology has been developed for large-scale inexpensive manufacture of Aflasafe products under the conditions present in many African nations. Results to date indicate that all Aflasafe products, registered and under experimental use, reduce aflatoxin concentrations in treated crops by >80% in comparison to untreated crops in both field and storage conditions. Benefits of aflatoxin biocontrol technologies are discussed along with potential challenges, including climate change, likely to be faced during the scaling-up of Aflasafe products. Lastly, we respond to several apprehensions expressed in the literature about the use of atoxigenic genotypes in biocontrol formulations. These responses relate to the following apprehensions: sorghum as carrier, distribution costs, aflatoxin-conscious markets, efficacy during drought, post-harvest benefits, risk of allergies and/or aspergillosis, influence of Aflasafe on other mycotoxins and on soil microenvironment, dynamics of Aspergillus genotypes, and recombination between atoxigenic and toxigenic genotypes in natural conditions.

Seasonal and geographical differences in aflatoxin exposures in Senegal

The aim of the study was to determine the geographical and seasonal variations in aflatoxin dietary exposure levels in adults from Senegal. A total of 168 adults (50% male) were recruited from three districts: Nioro du Rip (n=90), located in the Sudan Savannah agro-ecological zone where rainfall is sufficient for groundnut growth; Saint-Louis (n=40) and Mboro (n=38), located in the Sahel zone where groundnuts are produced under irrigated conditions. Diet information and samples were collected at groundnut harvest and post-harvest seasons. Plasma aflatoxin-albumin adducts (AF-alb) and total aflatoxin in household groundnut samples were measured by ELISA and a quantitative thin layer chromatography method, respectively. The blood AF-alb geometric mean was 45.7 pg/mg albumin (range 5.5-588.2 pg/mg). Nioro du Rip had a higher AF-alb level at harvest than Saint-Louis and Mboro (80.0 vs 15.6 and 33.3 pg/mg, P<0.001). Similar trends were observed at post-harvest (P<0.05). Seasonal trends were not consistent across the districts as Nioro du Rip had a higher AF-alb level at harvest than post-harvest (80.0 vs 58.6 pg/mg, P=0.026), whereas Saint-Louis had a higher level at post-harvest than harvest (25.6 vs 15.6 pg/mg, P=0.032). It is clear that aflatoxin exposure is prevalent in adults from Senegal and that season and geographical location are strong determinants of aflatoxin exposure.

Use of Quantitative Traits to Assess Aggressiveness of Phakopsora pachyrhizi Isolates from Nigeria and the United States

Soybean rust, caused by Phakopsora pachyrhizi, is one of the most important foliar diseases of soybean worldwide. The soybean-P. pachyrhizi interaction is often complex due to genetic variability in host and pathogen genotypes. In a compatible reaction, soybean genotypes produce tan-colored lesions, whereas in an incompatible reaction soybean genotypes produce an immune response (complete resistance) or reddish-brown lesions (incomplete resistance). In this study, in total, 116 and 72 isolates of P. pachyrhizi from Nigeria and the United States, respectively, were compared based on six quantitative traits to assess their aggressiveness on two soybean genotypes. All isolates produced reddish-brown lesions on plant introduction (PI) 462312 and tan lesions on TGx 1485-1D. The number of days after inoculation to first appearance of lesions, uredinia, and sporulation, along with the number of lesions and sporulating uredinia per square centimeter of leaf tissue, and the number of uredinia per lesion, were significantly (P < 0.001) different between the two soybean genotypes for all isolates from each country. The number of days to first appearance of lesions, uredinia, and sporulation were greater on PI 462312 than on TGx 1485-1D for all the test isolates. Similarly, the number of lesions and sporulating uredinia per square centimeter, and the number of uredinia per lesion were lower on PI 462312 than on TGx 1485-1D. For both soybean genotypes, the number of sporulating uredinia per square centimeter significantly (P = 0.0001) increased with an increase in the number of lesions per square centimeter. Although the slope of the regression of sporulating uredinia on number of lesions was greater (P < 0.0001) when TGx 1485-1D was inoculated with Nigerian isolates compared with U.S. isolates, slopes of the regression lines did not differ significantly (P > 0.0675) when PI 46312 was inoculated with Nigerian or U.S. isolates. This is the first study that used a large number of isolates from two continents to assess aggressiveness of P. pachyrhizi using multiple traits in soybean genotypes with contrasting types of disease reaction.

First Report of Mango Malformation Disease Caused by Fusarium tupiense in Senegal

Mango (Mangifera indica L.) is an economically important export crop for Senegal, producing about 100,000 tons of fruit annually. In April 2009, severe outbreaks of a new disorder occurred in mango orchards in the southeastern part of Casamance. Diseased plants showed abnormal growth of vegetative shoots with short thickened internodes and malformed inflorescence with short leaves interspersed among thickened sterile flowers that aborted early. These symptoms resembled those caused by mango malformation disease (4). To identify the causal agent, floral and vegetative samples from symptomatic mango plants were collected from Kolda district (12°53' N, 14°56' W). Malformed tissues were cut into 4-mm² pieces, surface sterilized with 75% ethanol for 2 min, dried, and plated on the Fusarium isolation medium Peptone PCNB Agar (PPA) (2). Fungal growth with Fusarium morphology were transferred on PPA and further purified on water agar as single spore isolates. Cultures were identified on the basis of spore characters on carnation leaf agar and colony morphology on PDA (2). Two isolates (I₄ and I₁₇) were similar to F. mangiferae/F. sterilihyphosum/F. tupiense complex (3). Macroconidia were slender, slightly falcate, three- to five-septate, 18.5 to 27.7 × 1.1 to 2.3 μm with slightly curved apical cell produced on cream to orange sporodochia. Microconidia were single-celled, oval, 3.7 to 13.6 × 0.75 to 1.1 μm produced on mono- and polyphialides in false heads. Chlamydospores were absent. To confirm the identity, genomic DNA was isolated from pure cultures of I₄ and I₁₇, used for amplification of portion of translation elongation factor (TEF-1α). Amplified products (241 bp) were purified and sequenced in both directions (GenBank Accession Nos. JX272929 and JX272930). A BLASTn search revealed 100% sequence identity with F. tupiense (DQ452860), 99% identity with F. mangiferae (HM135531) and F. sterilihyphosum (DQ452858) from Brazil. Phylogenetic analysis inferred from the Clustalw alignment of TEF-1α sequences clustered I₄ and I₁₇ isolates with F. tupiense (3). To confirm Koch's postulates, 2-year-old healthy mango seedlings var. Keitt and Kent (12 plants each) were inoculated by placing 20 μl conidial suspension (5 × 10⁷ conidia ml^-1) on micro-wounds created in apical and lateral buds. Inoculated buds were covered with filter paper soaked in the same spore suspension (1). Seedlings inoculated similarly with sterile distilled water served as control. Seven months after the inoculation, typical malformation symptoms were observed on vegetative parts on all inoculated plants, but not on control plants. F. tupiense was reisolated from symptomatic shoots of inoculated plants. Based on the morphological characteristics, sequence analysis, and pathogenicity test, the pathogen of mango malformation in Senegal was identified as F. tupiense (3). To our knowledge, this is the first confirmed record in Senegal of mango malformation caused by F. tupiense. This disease is a serious threat to mango production and trade of Senegal. Urgent actions are necessary to stop this emerging epidemic that can spread to other countries in West Africa. References: (1) S. Freeman et al. Phytopathol. 6:456, 1999. (3) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual, Blackwell Publishing, Ames, IA, 2006. (4) C. S. Lima et al. Mycologia. 104: in press (doi: 10.3852/12-052). (2) W. F. O. Marasas et al. Phytopathol. 96:667, 2006.

Fungal and bacterial metabolites in commercial poultry feed from Nigeria

Metabolites of toxigenic fungi and bacteria occur as natural contaminants (e.g. mycotoxins) in feedstuffs making them unsafe to animals. The multi-toxin profiles in 58 commercial poultry feed samples collected from 19 districts in 17 states of Nigeria were determined by LC/ESI-MS/MS with a single extraction step and no clean-up. Sixty-three (56 fungal and seven bacterial) metabolites were detected with concentrations ranging up to 10,200 µg kg⁻¹ in the case of aurofusarin. Fusarium toxins were the most prevalent group of fungal metabolites, whereas valinomycin occurred in more than 50% of the samples. Twelve non-regulatory fungal and seven bacterial metabolites detected and quantified in this study have never been reported previously in naturally contaminated stored grains or finished feed. Among the regulatory toxins in poultry feed, aflatoxin concentrations in 62% of samples were above 20 µg kg⁻¹, demonstrating high prevalence of unsafe levels of aflatoxins in Nigeria. Deoxynivalenol concentrations exceeded 1000 µg kg⁻¹ in 10.3% of samples. Actions are required to reduce the consequences from regulatory mycotoxins and understand the risks of the single or co-occurrence of non-regulatory metabolites for the benefit of the poultry industry.

First Report of Leaf Blight of Taro (Colocasia esculenta) Caused by Phytophthora colocasiae in Ghana

Taro (Colocasia esculenta (L.) Schott) is an important food crop cultivated for its edible tubers in Ghana. In May 2009, outbreaks of a destructive leaf disease were observed on several taro farms in the Atiwa, East-Akim, Fanteakwa, West-Akim, and New Juaben districts of the Eastern Region of Ghana. Symptoms began on leaves as small, brown, water-soaked lesions that enlarged and coalesced into large lesions with yellow exudate, ultimately leading to the defoliation and death of plants. Symptoms were suggestive of taro leaf blight (TLB) caused by Phytophthora colocasiae Raciborski (3). By August 2010, the disease had spread to other taro-growing regions in Ghana. To identify the pathogen, leaf tissue from lesion margins were excised and plated on carrot agar and V8 selective media for Phytophthora and incubated at 27°C for 5 days (2). Growth from diseased tissue was used for morphological characterization. Sporangia were ovoid, hyaline, papillate, caducous, 30 to 60 × 17 to 28 μm, and pedicels were 3.5 to 10 μm long. Genomic DNA was isolated from pure cultures of two isolates, PCg11-2 from Oseim (6°15'N, 0°27'E) and PCg11-5 from Oyoko (6°8'N, 0°17'W). Ribosomal DNA ITS1, 5.8S and ITS2 were amplified by PCR using the ITS1 and ITS4 primers (4). The resultant 784-bp amplicons were sequenced (GenBank Accession Nos. JN662439 and JN662440). Sequences of both isolates were identical. A BLASTn search of these sequences revealed maximum homology of 99% with the sequence of P. colocasiae strains from blighted taro leaves in Nigeria (GenBank Accession No. HQ602756), Hawaii (GenBank Accession No. GU258997), and several strains in Asia and the South Pacific. On the basis of morphological characteristics and nucleotide homology, the isolates were identified as P. colocasiae. To fulfill Koch's postulates, 30 leaf discs from 3-month-old plants were inoculated with 10 μl of a suspension of 3 × 10⁵ zoospores per ml (2). Leaf discs were incubated in the dark at 27°C on wet foam in plastic trays for 5 days. All inoculated discs developed blight symptoms similar in appearance to those observed on diseased taro in the fields. Control discs remained asymptomatic. P. colocasiae was reisolated from leaf discs and its identity confirmed by morphological characteristics. To our knowledge, this is the first report of TLB and P. colocasiae in Ghana. Occurrence of TLB was recently reported in Nigeria (1). The recent occurrence of TLB in both Nigeria and Ghana threaten the taro-growing regions of West and Central Africa. Disease surveys and a management strategy that includes resistant varieties are urgently needed. References: (1) R. Bandyopadhyay et al. Plant Dis. 95:618, 2011. (2) A. Drenth and B. Sendall. Practical Guide to Detection and Identification of Phytophthora. Version 1.0. CRC for Tropical Plant Protection. Brisbane, Australia, 2001. (3) M. Raciborski. Java Batavia Bull. 19:189, 1900. (4) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, CA, 1990.

Primary cutaneous precursor B-cell lymphoblastic lymphoma with late dissemination

A 20-year-old woman presented with multiple painless nodular swellings on the skin of the extremities and face, without any systemic symptoms. Biopsy with immunohistochemistry revealed a diagnosis of precursor B-cell lymphoblastic lymphoma. There was no extracutaneous site of involvement. The patient denied chemotherapy and was subsequently lost to follow-up. She presented with symptomatic disseminated disease 18 months later and rapidly succumbed to her illness.