Identification of Atoxigenic Aspergillus flavus Isolates to Reduce Aflatoxin Contamination of Maize in Kenya

Aspergillus flavus has two morphotypes, the S strain and the L strain, that differ in aflatoxin-producing ability and other characteristics. Fungal communities on maize dominated by the S strain of A. flavus have repeatedly been associated with acute aflatoxin poisonings in Kenya, where management tools to reduce aflatoxin levels in maize are needed urgently. A. flavus isolates (n = 290) originating from maize produced in Kenya and belonging to the L strain morphotype were tested for aflatoxin-producing potential. A total of 96 atoxigenic isolates was identified from four provinces sampled. The 96 atoxigenic isolates were placed into 53 vegetative compatibility groups (VCGs) through complementation of nitrate non-utilizing mutants. Isolates from each of 11 VCGs were obtained from more than one maize sample, isolates from 10 of the VCGs were detected in multiple districts, and isolates of four VCGs were found in multiple provinces. Atoxigenic isolates were tested for potential to reduce aflatoxin concentrations in viable maize kernels that were co-inoculated with highly toxigenic S strain isolates. The 12 most effective isolates reduced aflatoxin levels by >80%. Reductions in aflatoxin levels caused by the most effective Kenyan isolates were comparable with those achieved with a United States isolate (NRRL-21882) used commercially for aflatoxin management. This study identified atoxigenic isolates of A. flavus with potential value for biological control within highly toxic Aspergillus communities associated with maize production in Kenya. These atoxigenic isolates have potential value in mitigating aflatoxin outbreaks in Kenya, and should be evaluated under field conditions.

Dynamics of Soybean Rust Epidemics in Sequential Plantings of Soybean Cultivars in Nigeria

Soybean rust, caused by Phakopsora pachyrhizi, is an important foliar disease of soybean. Disease severity is dependent on several environmental factors, although the precise nature of most of these factors under field conditions is not known. To help understand the environmental factors that affect disease development, soybean rust epidemics were studied in Nigeria by sequentially planting an early-maturing, highly susceptible cultivar, TGx 1485-1D, and a late-maturing, moderately susceptible cultivar, TGx 1448-2E, at 30- to 45-day intervals from August 2004 to September 2006. Within each planting date, disease onset occurred earlier on TGx 1485-1D than on TGx 1448-2E, and rust onset was at least 20 days earlier on soybean planted between August and October than on soybean planted between November and April. The logistic model provided a better description of the temporal increase in rust severity than the Gompertz model. Based on the logistic model, the highest absolute rates of disease increase were observed on soybean planted in September 2006 and October 2004 for TGx 1485-1D and TGx 1448-2E, respectively. Disease severity as measured by the relative area under disease progress curve (RAUDPC) was significantly (P < 0.05) negatively correlated with evaporation (r = -0.73), solar radiation (r = -0.59), and temperature (r = -0.64) but positively correlated with urediniospore concentration (r = 0.58). Planting date and soybean cultivar significantly (P < 0.05) affected disease severity, with severity being higher on soybean crops planted during the wet season than those planted in the dry season. Within the wet season, planting in May and July resulted in a significantly (P < 0.05) lower RAUDPC than planting between August and October. Yields were significantly (P < 0.001) related to RAUDPC during the wet season, whereby an increase in RAUDPC resulted in a linear decrease in yield. This study suggests that selection of planting date could be a useful cultural practice for reducing soybean rust.

Mediastinal teratoma mimicking massive pleural effusion

Immature mediastinal teratoma is very rare, found in only 1% of all mediastinal teratomas. Raised serum alpha feto-protein acts as important surrogate marker for both diagnosis and follow up in such cases. Surgery and adjuvant chemotherapy are keys in the management, especially in patients older than 15 years of age. We present a 14-year-boy presenting clinico-radiologically as left sided massive pleural effusion. Raised serum marker as well as excision biopsy of the mediastinal mass following thoracotomy were indicative of a diagnosis of immature teratoma.

An enhancer-like element present in the promoter of a T-DNA gene from the Ti plasmid of Agrobacterium tumefaciens

The promoter of the 780 gene of T-right [Thomashow, M., Nutter, R., Montoya, A., Gordon, M. & Nester, E. (1980) Cell 19, 729-739] from Agrobacterium tumefaciens Ti plasmid (pTi15955) was shown to contain an upstream cis-acting element (activator) having enhancer-like properties. To characterize the properties of this promoter element, it was placed in both polarities, upstream and downstream of a Delta-37 deletion mutant of the 780 gene. The Delta-37 deletion contains the entire 780 gene with the 5' flanking sequences deleted upstream of TATA to -37. The effect of the activator on in vivo transcriptional activity was assessed by S1 nuclease mapping utilizing a homologous reference gene as an internal standard. Transcript levels from sunflower crown gall tumors were between 127% and 90% of the wild-type 780 gene depending on the polarity of the activator element when placed directly upstream to the 780 gene Delta-37 promoter. Repositioning the activator element 613 base pairs further upstream increased transcription by 2-fold regardless of polarity. However, the activator element did not promote transcription when placed in either polarity approximately 200 base pairs downstream of the poly(A) addition site. Upstream promoter fragments (TATA-distal) from the octopine synthase (ocs) and agropine synthase (ags) genes were also tested for activation of the Delta-37 construction. The ocs sequences activated transcription of the Delta-37 deletion to 14% of wild-type levels when placed upstream in the B (reverse) orientation. All other constructions with the ocs and ags sequences showed no enhancement of promoter activity.

Profile of tuberculous meningitis with or without HIV infection and the predicators of adverse outcome

OBJECTIVES

To compare the clinical, radiological and cerebrospinal fluid (CSF) findings, at hospital admission, among adult patients with tuberculous meningitis (TBM) with or without HIV infection and to identify the factors that predict adverse outcome at six months.

METHODS

A total of 82 adult patients with TBM were included (40 HIV-positive and 42 HIV-negative). Several clinical (duration of illness, Glasgow Coma Scale score, presence of high temperature, headache, cranial nerve or sphincter abnormality, seizures and endocrine dysfunction), radiological (presence of hydrocephalus, cerebral infarction and oedema, meningeal enhancement, granuloma) and cerebrospinal fluid parameters (glucose, protein, lactate, lymphocytes, neutrophils and adenosine deaminase values) were recorded along with CD4 count in the peripheral blood. Statistical analysis was performed using the chi-square test. Individual variables were evaluated as prognostic factors for adverse outcome in both groups by calculating the relative risk of association for each.

RESULTS

Temperature more than 38.33 degrees C was more common in the HIV-negative group while seizures, hydrocephalus, cerebral infarction and low CD4 count occurred significantly more commonly in the HIV-positive group. Hydrocephalus had strong association with severe neurological deficit and seizure with death in both the groups.

CONCLUSION

Several clinical and laboratory features of TBM in patients who are HIV-positive are distinctly different from those without HIV infection; some of these have an association with the probability of adverse outcome.

Pathogenic variation of Phakopsora pachyrhizi infecting soybean in Nigeria

Soybean rust, caused by Phakopsora pachyrhizi, is an important disease in Nigeria and many other soybean-producing countries worldwide. To determine the geographical distribution of soybean rust in Nigeria, soybean fields were surveyed in the Derived Savanna (DS), Northern Guinea Savanna (NGS), and Southern Guinea Savanna (SGS) agroecological zones in Nigeria between 2004 and 2006. Disease severity in each zone was determined and analyzed using geostatistics. Prevalence of infected fields and disease severity in surveyed fields were significantly (P < 0.05) different between geographical zones with both variables being higher in the DS zone than in either NGS or SGS zones. Geostatistical analysis indicated that the spatial influence of disease severity at one location on severity at other locations was between 75 and 120 km. An exponential model best described the relationship between semivariance and lag distance when rust severity was high. Spatial interpolation of rust severity showed that locations in the DS zone were more conducive for the rust epidemic compared to areas in the NGS zone. In the 2005 survey, 116 purified isolates were established in culture on detached soybean leaves. To establish the nature of pathogenic variation in P. pachyrhizi, a set of four soybean accessions with Rpp(1), Rpp(2), Rpp(3), and Rpp(4) resistance genes, two highly resistant and two highly susceptible genotypes were inoculated with single uredinial isolates. Principal component analysis on the number of uredinia per square centimeter of leaf tissue for 116 isolates indicated that an adequate summary of pathogenic variation was obtained using only four genotypes. Of these four, PI 459025B (with Rpp(4) gene) and TGx 1485-1D had the lowest and highest number of uredinia per square centimeter, respectively. Based on cluster analysis of the number of uredinia per square centimeter, seven pathotype clusters were determined. Isolates in cluster III were the most virulent, while those in cluster IV were the least virulent. Shannon's index (H) revealed a more diverse pathogen population in the DS zone (H = 1.21) compared to the rust population in SGS and NGS with H values of 1.08 and 0.91, respectively. This work will be useful in breeding and management of soybean rust by facilitating identification of resistant genotypes and targeting cultivars with specific resistance to match prevailing P. pachyrhizi pathotypes in a given geographical zone.

Alteration of timing of secretion of vascular endothelial growth factors is responsible for progression of diabetic retinopathy

Diabetic retinopathy is one of the most common complications in diabetes mellitus due to persistent hyperglycaemia. Various biochemical mechanisms have been suggested to cause this complication. The authors' present study which included 100 patients of type-2 diabetes mellitus with different stages of diabetic retinopathy and without retinopathy shows that initiation of diabetic retinopathy is associated with increased anaerobic glycolysis and accelerated oxidative stress. Progression of this complication is guided by increased secretion of vascular endothelial growth factors. It is our assumption that increased secretion of vascular endothelial growth factors in early part of this disease e.g. before occurrence of morphological abnormality may modify this complication.

Evaluation of Soybean Germplasm for Resistance to Soybean Rust (Phakopsora pachyrhizi) in Nigeria

Soybean rust, caused by Phakopsora pachyrhizi, is one of the most important constraints to soybean production worldwide. The absence of high levels of host resistance to the pathogen has necessitated the continued search and identification of sources of resistance. In one set of experiments, 178 soybean breeding lines from the International Institute of Tropical Agriculture were rated for rust severity in the field in 2002 and 2003 at Ile-Ife, Yandev, and Ibadan, Nigeria. Thirty-six lines with disease severity ≤3 (based on a 0-to-5 scale) were selected for a second round of evaluation in 2004 at Ibadan. In the third round of evaluation under inoculated field conditions, 11 breeding lines with disease severity ≤2 were further evaluated for rust resistance at Ibadan in 2005 and 2006. The breeding lines TGx 1835-10E, TGx 1895-50F, and TGx 1903-3F consistently had the lowest level of disease severity across years and locations. In another set of experiments, 101 accessions from the United States Department of Agriculture-Agricultural Research Service and National Agriculture Research Organization (Uganda) were evaluated in the first round in 2005 under inoculated conditions in the screenhouse; 12 accessions with disease severity ≤20% leaf area infected were selected for evaluation in the second round in 2005 and 2006 under inoculated field conditions at Ibadan. Highly significant differences (P < 0.0001) in disease severity were observed among the 101 accessions during this first round of rust evaluation. Significant (P < 0.0001) differences in rust severity and sporulation also were observed among the 12 selected accessions. Accessions PI 594538A, PI 417089A, and UG-5 had significantly (P < 0.05) lower disease severity than all other selected accessions in both years of evaluation, with rust severities ranging from 0.1 to 2.4%. These results indicate that some of the breeding lines (TGx 1835-10E, TGx 1895-50F, and TGx 1903-3F) and accessions (PI 594538A, PI 417089A, and UG-5) would be useful sources of soybean rust resistance genes for incorporation into high-yielding and adapted cultivars.

Novel Sources of Resistance to Fusarium Stalk Rot of Maize in Tropical Africa

Fusarium stalk rot is one of the most widespread and destructive diseases of maize, and deployment of resistant genotypes is one of the most effective strategies for controlling the disease. Fifty inbred lines and four checks from the breeding program of the International Institute of Tropical Agriculture were evaluated in field trials at Ikenne and Ibadan, Nigeria in 2003 and 2004 to identify new sources of resistance to stalk rot caused by Fusarium verticillioides. Evaluations were conducted under artificial inoculation and natural infection at Ibadan and Ikenne, respectively. Disease severity was recorded using a severity scale (SS) and direct estimation of stalk discoloration (SD). The two methods of disease assessment were compared and combined to classify genotypes into resistance groups using results from rank-sum analysis. In 2003, disease severity ranged from SS = 1 to 5 and SD = 1.3 to 33.8% at both locations. Both SS and SD were significantly (P < 0.01) higher in 2003 than in 2004 at the two locations. In both years, inbred lines significantly differed in SS (P < 0.02) and SD (P < 0.04) at Ibadan. Similarly, inbred lines significantly differed in SS (P < 0.04) and SD (P < 0.04) when genotypes were evaluated at Ikenne. Disease assessments based on SS and SD were significantly correlated (0.68 < r < 0.95, P < 0.01) in both years. Based on the results from rank-sum analysis, inbred lines were separated into highly resistant, resistant, moderately resistant, moderately susceptible, susceptible, and highly susceptible groups. At Ibadan, 6 (11.1%) and 8 (14.8%) were identified as highly resistant and resistant, respectively, whereas 11 (20.4%) were identified as resistant at Ikenne. Inbred lines 02C14609, 02C14643, 02C14654, and 02C14678 were consistently classified as either highly resistant or resistant to stalk rot across locations and years while the check genotypes were classified either as susceptible or moderately susceptible to stalk rot. These four inbred lines identified to have high levels of disease resistance may be used for breeding maize with resistance to Fusarium stalk rot.

Scleredema of Buschke: a rare post-streptococcal complication

A 19-year male presented with acute onset, gradually progressive symmetric indurations involving the skin over the face, neck, shoulders and upper part of chest following an upper respiratory tract infection. Detailed history and examination did not reveal evidence of Raynauds' phenomenon, nail changes, digital ulcers, pigmentation or any systemic involvement. Autoantibodies for systemic sclerosis were absent. Histopathology of skin biopsy documented scleredema. Antistreptolysin O (ASO) titer was elevated. We diagnosed a case of Scleredema adultorum of Buschke following a streptococcal throat infection. We report this case to highlight the importance of clinically differentiating this relatively benign, self-limiting disorder from systemic sclerosis.

First Report of Rust Caused by Phakopsora pachyrhizi on Soybean in Democratic Republic of Congo

Nigeria (1) and Uganda (3) are the closest countries to the Democratic Republic of Congo (DRC) where soybean rust caused by Phakopsora pachyrhizi has been reported. In February 2007, during a disease survey in DRC, soybean (Glycine max) leaves with rust symptoms (tan, angular lesions with erumpent sori exuding urediniospores) were observed in 10 fields in the following areas in Bas Congo Province: Bangu, Kimpese, Kolo-Fuma, Lukala, Mbanza-Ngungu, Mpalukide, Mvuazi, and Ntemo. Rust incidence in these fields ranged from 85 to 100%, while severity ranged between 3 and 35% of the leaf area on infected plants. Urediniospores were hyaline, minutely echinulate, and 23 to 31 × 16 to 20 μm. Within a week of collection, infected leaf samples were sent to the USDA-ARS Foreign Disease-Weed Science Research Unit (FDWSRU) for pathogen identification. DNA was extracted from sections of leaves containing sori with the Qiagen DNeasy Plant Mini kit (Valencia, CA), and all 10 field samples amplified in a real-time fluorescent PCR with the P. pachyrhizi-specific primers Ppm1 and Ppa2 (2). Infected leaves of cultivar Vuangi collected from one field each in the INERA Research Station, Kimpese-Crawford, and Kimpese-Ceco were separately washed in sterile water to collect urediniospores that were used to separately inoculate three detached leaves of susceptible cultivar TGx 1485-1D (4). Lesions on inoculated leaves developed 5 days after inoculation (DAI), and pustules (110 to 130 μm) formed 7 DAI and erupted 2 days later exuding columns of urediniospores similar in size to the initially collected isolates. Inoculation of another set of detached leaves with a spore suspension (1 × 10⁶ spores per ml) from the first set of detached leaves resulted in typical rust symptoms. Seedlings of cultivar Williams also showed typical rust symptoms when inoculated separately with urediniospores collected from nine fields (i.e., all except Kimpese-Ceco, which was infective in the detached leaf assay). Inoculation and incubation were carried out at the FDWSRU Plant Pathogen Containment Facility at Fort Detrick as described earlier (2). The PCR assay, morphological characters of the isolates, and pathogenicity tests demonstrate that P. pachyrhizi occurs in DRC. To our knowledge, this is the first report of P. pachyrhizi infecting soybean in DRC. References: (1) O. A. Akinsanmi et al. Plant Dis. 85:97, 2001. (2) R. D. Frederick et al. Phytopathology 92:217, 2002. (3) E. Kawuki et al. J. Phytopathol. 151:7, 2003. (4) M. Twizeyimana et al. Online publication. http://www.plantmanagementnetwork.org/ infocenter/topic/soybeanrust/2006/posters/41.asp. Plant Management Network, 2006.

Comparison of Field, Greenhouse, and Detached-Leaf Evaluations of Soybean Germplasm for Resistance to Phakopsora pachyrhizi

Fourteen soybean accessions and breeding lines were evaluated for resistance to soybean rust caused by the fungus Phakopsora pachyrhizi. Evaluations were conducted in replicated experiments in growth chambers using detached leaves and under greenhouse and field conditions. In growth-chamber experiments, inoculation of detached leaves with 1 × 10⁶ spores/ml resulted in a significantly (P < 0.0001) higher total number of pustules and spores per unit leaf area than inoculations with lower spore concentrations. Amending agar medium with plant hormones significantly (P < 0.0001) aided retention of green leaf color in detached leaves. Leaf pieces on a medium containing kinetin at 10 mg/liter had 5% chlorosis at 18 days after plating compared with leaf pieces on media amended with all other plant hormones, which had higher levels of chlorosis. Leaf age significantly affected number of pustules (P = 0.0146) and number of spores per pustule (P = 0.0088), and 3- to 4-week-old leaves had a higher number of pustules and number of spores per pustule compared with leaves that were either 1 to 2 or 5 to 6 weeks old. In detached-leaf and greenhouse screening, plants were evaluated for days to lesion appearance, days to pustule formation, days to pustule eruption, lesion number, lesion diameter, lesion type, number of pustules, and spores per pustule in 1-cm² leaf area. Plants also were evaluated for diseased leaf area (in greenhouse and field screening) and sporulation (in field screening) at growth stage R6. There were significant (P < 0.0001) differences among genotypes in their response to P. pachyrhizi infection in the detached-leaf, greenhouse, and field evaluations. Accessions PI 594538A, PI 417089A, and UG-5 had very low levels of disease compared with the susceptible checks and all other genotypes. Detached-leaf, greenhouse, and field results were comparable, and there were significant correlations between detached-leaf and greenhouse (absolute r = 0.79; P < 0.0001) and between detached-leaf and field resistance (absolute r = 0.83; P < 0.0001) across genotypes. The overall results show the utility of detached-leaf assay for screening soybean for rust resistance.

First Report of Soybean Rust Caused by Phakopsora pachyrhizi in Ghana

Nigeria is the only country in West Africa where soybean rust, caused by Phakopsora pachyrhizi, has been officially reported (1). During a disease survey in Ghana during October 2006, soybean (Glycine max) leaves with rust symptoms (tan, angular lesions with erumpent sori exuding urediniospores) were observed in 11 fields in the following districts: Kassena Nankana in the Upper East Region; East Gonja, Central Gonja, and Tolon-Kumbungu in the Northern Region; and Ejisu-Juabeng in the Ashanti Region. Disease incidence in these fields ranged from 50 to 100% and disease severity ranged between 3 and 40% of the leaf area on infected plants. Urediniospores were hyaline, minutely echinulate, and 23 to 31 × 14 to 18 μm. Within a week of collection, leaf samples were sent to the USDA-ARS Foreign Disease-Weed Science Research Unit for verification of pathogen identity. DNA was extracted from leaf pieces containing sori with the Qiagen DNeasy Plant Mini kit (Valencia, CA), and all 11 field samples amplified in a real-time fluorescent PCR with the P. pachyrhizi-specific primers Ppm1 and Ppa2 (2). Sequence alignment of the internal transcribed spacer (ITS) region 2 further confirmed the identification as P. pachyrhizi (2). Infected leaves from three fields were separately washed in sterile water to collect urediniospores that were used to separately inoculate three detached leaves (for each isolate) of susceptible cultivar TGx 1485-1D (3). The abaxial surface of detached leaves was sprayed with 400 μl of spore suspension (1 × 10⁶ spores per ml). A single leaf piece was placed in a 9-cm-diameter petri dish with adaxial side appressed on 1% technical agar amended with 10 μg/ml of kinetin. Lactic acid (1.5 ml/liter) and benomyl (12.5 mg/liter) were added to the agar medium to inhibit growth of saprophytic fungi and bacteria. Petri dishes were incubated at 20°C with a 12-h light/12-h dark cycle. Lesions on inoculated leaves developed 5 to 6 days after inoculation (DAI), and pustules (105 to 120 μm) formed 7 to 8 DAI and erupted 3 days later exuding columns of urediniospores similar in size to the initially collected isolates. Inoculating another set of detached leaves with a spore suspension (1 × 10⁶ spores per ml) from the first set of detached leaves resulted in typical rust symptoms. The PCR assay, alignment of ITS region 2, morphological characters of the isolates, and pathogenicity tests demonstrate that P. pachyrhizi occurs in Ghana. To our knowledge, this is the first report of P. pachyrhizi in Ghana. References: (1) O. A. Akinsanmi et al. Plant Dis. 85:97, 2001. (2) R. D. Frederick et al. Phytopathology 92:217, 2002. (3) M. Twizeyimana et al. Online publication. http://www.plantmanagementnetwork.org/ infocenter/topic/soybeanrust/2006/posters/41.asp. Plant Management Network, 2006.

Rapid Screening of Musa Species for Resistance to Black Leaf Streak Using In Vitro Plantlets in Tubes and Detached Leaves

This study investigated the utility of inoculation of in vitro plantlets in tubes and detached leaves as reliable and rapid assays for screening Musa genotypes against Mycosphaerella fijiensis, the causal agent of black leaf streak. In the first part of the study, three types of inocula were evaluated to determine suitability for in vitro inoculation. Inoculation of in vitro plantlets with mycelial fragments resulted in significantly (P < 0.05) higher levels of disease severity and faster rates of disease progress compared with inoculations using conidial suspensions. In the detached leaf assay, amending agar medium with plant hormones significantly (P < 0.0001) aided retention of green leaf color. Leaf pieces on medium containing gibberellic acid at 5 mg/liter had about 5% chlorosis at 52 days after plating. When in vitro plantlets in tubes and detached leaves of 10 Musa genotypes with different levels of disease resistance were inoculated with M. fijiensis, there were significant (P < 0.05) differences among genotypes in leaf area infected, incubation time, and symptom evolution time. For incubation time and leaf area infected, cultivars responded depending on their level of disease resistance, with resistant genotypes Calcutta-4 and PITA-17 having significantly (P = 0.001) longer incubation times and lower infected leaf areas compared with the susceptible cultivar Agbagba and moderately resistant cultivar FHIA-23. A similar pattern in cultivar response was observed for symptom evolution time. Leaf area infected was not significantly (P = 0.2817 for two-tailed t test) different when assessed using the two assays, and infected leaf areas in both assays were strongly correlated (r = 0.88, n = 48, P < 0.0001). Although incubation times were significantly (P = 0.0062 for two-tailed t test) different between the two assays, values from the two assays were strongly correlated (r = 0.69, n = 48, P < 0.0001). These results show that these two assays are rapid and space-effective, and can reliably be used for screening Musa genotypes for resistance to black leaf streak.

Evaluation of Maize Inbred Lines for Resistance to Fusarium Ear Rot and Fumonisin Accumulation in Grain in Tropical Africa

Fusarium ear rot and fumonisin contamination is a major problem facing maize growers worldwide, and host resistance is the most effective strategy to control the disease, but resistant genotypes have not been identified. In 2003, a total of 103 maize inbred lines were evaluated for Fusarium ear rot caused by Fusarium verticillioides in field trials in Ikenne and Ibadan, Nigeria. Disease was initiated from natural infection in the Ikenne trial and from artificial inoculation in the Ibadan trial. Ear rot severity ranged from 1.0 to 6.0 in both locations in 2003. Fifty-two inbred lines with disease severity ≤3 (i.e., ≤ 10% visible symptoms on ears) were selected and reevaluated in 2004 for ear rot resistance, incidence of discolored kernels, and fumonisin contamination in grain. At both locations, ear rot severity on the selected lines was significantly (P < 0.0020) higher in 2004 than in 2003. The effects of selected inbred lines on disease severity were highly significant at Ikenne (P = 0.0072) and Ibadan (P < 0.0001) in 2004. Inbred lines did not affect incidence of discolored kernels at both locations and across years except at Ikenne (P = 0.0002) in 2004. Similarly, significant effects of inbred lines on fumonisin concentration were observed only at Ikenne (P = 0.0201) in 2004. However, inbred lines 02C14585, 02C14593, 02C14603, 02C14606, 02C14624, and 02C14683 had consistently low disease severity across years and locations. Fumonisin concentration was significantly correlated with ear rot only at Ikenne (R = 0.42, P < 0.0001). Correlation between fumonisin concentration and incidence of discolored kernels was also significant at Ikenne (R = 0.39, P < 0.0001) and Ibadan (R = 0.35, P = 0.0007). At both locations, no significant inbred × year interaction was observed for fumonisin concentration. Five inbred lines, namely 02C14585, 02C14603, 02C14606, 02C14624, and 02C14683, consistently had the lowest fumonisin concentration in both trials. Two of these inbred lines, 02C14624 and 02C14585, had fumonisin levels <5.0 μg/g across years in trials where disease was initiated from both natural infection and artificial inoculation. These lines that had consistently low disease severity are useful for breeding programs to develop fumonisin resistant lines.

Observations of hepatic encephalopathy profile in a tertiary care centre

A study was conducted among 67 patients presenting with hepatic encephalopathy to establish the aetiological diagnosis and record the incidence of acute and chronic liver diseases. They all had undergone thorough clinical and laboratory evaluation. The factor precipitating encephalopathy was also identified. Among 67 patients 19 (28.4%) had acute liver disease and 48 (71.6%) had chronic liver disease. Majority of patients had grade 2 encephalopathy at presentation. Among the acute cases most common aetiology was acute viral hepatitis due to hepatitis B and E viruses whereas alcoholic liver disease was the most frequent cause of chronic liver disease. The most common precipitating factor was gastro-intestinal haemorrhage.

Microscopic dynamics of recovery in sheared depletion gels

We report x-ray photon correlation spectroscopy and diffusing wave spectroscopy studies of depletion gels formed from nanoscale silica colloids in solutions of nonabsorbing polymer following the cessation of shear. The two techniques provide a quantitatively coherent picture of the dynamics as ballistic or convective motion of colloidal clusters whose internal motion is arrested. While the dynamics possesses features characteristic of nonergodic soft solids, including a relaxation time that grows linearly with the time since shear, comparison with behavior of quenched supercooled liquids indicates that this evolution is not directly related to traditional aging phenomena in glasses.

Correlation of lipid profile and carotid artery plaque as detected by Doppler ultrasound in ischaemic stroke patients--A hospital-based study

Stroke is one of the leading causes of morbidity and mortality all over the world. Carotid plaque formation and intima media thickness can be a predictor of ischaemic stroke. In this regard studies from our country, are few and far between. This is a small hospital-based study to look in to this matter. We have assessed the intima media thickness of the common carotid as well as the internal and external carotid arteries by the ultrasound method. The lipid profiles were estimated and correlated with the intima media thickness. Results indicate that in the common as well as in the internal and external carotid arteries, the intima media thickness is a good predictor of ischaemic stroke. This thickness is also well correlated with the lipid levels in blood. Hence this non-invasive method can be used successfully to identify the high risk patients, prone to develop stroke.

Isolated massive thyroid metastasis in lung cancer

Metastasis to the thyroid gland is rare despite its rich vascular supply. Among the pulmonary malignancies metastasising to the thyroid, adenocarcinomas are the commonest. The appearance of metastatic disease in lung carcinoma indicates a poor prognosis and the average survival is two months. We report a 62-year-old woman with squamous cell carcinoma of lung metastatic to the thyroid that produced massive enlargement of the gland. The appearance of the secondary preceded the diagnosis of the primary malignancy by a few months. Ultimately, the patient succumbed to her disease.