SESSION TYPE: Infectious Disease Student/Resident Case Report Posters IPRESENTED ON: Tuesday, October 23, 2012 at 01:30 PM - 02:30 PM

INTRODUCTION:

Acute pericarditis is the admitting diagnosis in approximately 5% of patients visiting emergency department (ED) with non-cardiac chest pain. In most patients, the cause of acute pericarditis is thought to be idiopathic. Other common causes include viral infections, renal failure, myocardial infarction (MI), malignancy, radiation, and trauma.

CASE PRESENTATION:

A 34 year-old diabetic female is presents to ED with one episode of syncope. 4 weeks prior to this episode, she was treated for upper respiratory infection with cefuroxime as outpatient. Symptoms re-started 1 week back accompanied with fever, shortness of breath and some abdominal pain. CT abdomen with contrast reveals normal abdomen but 3 cm of pericardial effusion and bilateral moderate pleural effusion. She is diagnosed with viral pericarditis and discharged home on NSAIDs. At current admission, transthoracic echocardiogram reveals thickened pericardium, large pericardial effusion and early cardiac tamponade. She undergoes emergent pericardiocentesis with drainage of 800 ml amber colored fluid. It does not show any malignancy or infectious. She is discharged home. She returns to ED with left side chest pain and shortness of breath and found to have atrial flutter on Electrocardiograph. After failed medical treatment, she undergoes trans-esophageal echocardiogram and direct current-cardioversion and reverts to sinus. Chest x-ray obtained at this admission reveals multiple new bilateral pulmonary nodules, right hilar and mediastinal adenopathy, with resolved pleural and pericardial effusion. This is later confirmed with Chest CT with contrast. Oncology is consulted and she undergoes extensive blood work and imaging which turns out to be non-diagnostic. CT guided core biopsy of the right lung nodule is performed which reveals granulomatous inflammation with fungal organisms suggestive of histoplasma identified on Gomori's Methenamine Silver (GMS) stain. She is treated with itraconazole for 6 weeks with good response.

DISCUSSION:

Histoplasmosis should be considered in patients with pericardial disease from endemic areas, particularly when associated with intrathoracic adenopathy unlike our case. Tissue culture is the gold standard for the definite diagnosis of the histoplasmosis but most pathologists are able to identify the budding yeasts on methenamine silver or periodic acid-Schiff staining of tissues.

CONCLUSIONS:

Prompt response to anti-inflammatory medications and failure to identify H. capsulatum in the pericardial fluid or tissue support a noninfectious, inflammatory mechanism for this complication.1) Wheat et al. Pericarditis as a manifestation of histoplasmosis during two large urban outbreaks. Medicine (Baltimore). 1983 Mar;62(2):110-9.2) Kauffman et al. Histoplasmosis: a Clinical and Laboratory Update. CLINICAL MICROBIOLOGY REVIEWS, Jan. 2007, p. 115-132 Vol. 20, No. 10893-8512/073) Picardi et al. Pericarditis caused by Histoplasma capsulatum. Am. J.Cardiol. 37:82-88.DISCLOSURE: The following authors have nothing to disclose: Puneet Agarwal, Sujay BangarulingamNo Product/Research Disclosure InformationUniversity of Illinois, Urbana-Champaign, Urbana, IL.

SESSION TYPE: Infectious Disease Case Report Posters IIPRESENTED ON: Tuesday, October 23, 2012 at 01:30 PM - 02:30 PM

INTRODUCTION:

Disseminated histoplasmosis is uncommon in an immune competent adult. We report a case of disseminated histoplasmosis presenting as multiple ring enhancing intracranial cystic lesions in an immune competent adult.

CASE PRESENTATION:

A 20-year-old Caucasian male presented with 10 days of high grade fever, headache and altered mental status. Review of systems revealed nausea , vomiting ,chest discomfort and bouts of inappropriate laughter. He had fever (101.5 F),tachycardia (105),tachypanea (27) and oxygen saturation of 96 % on room air. Physical exam was normal other than nuchal rigidity, diffusely brisk deep tendon reflexes and ankle clonus. Initial laboratory work was normal except an elevated WBC count (16900).HIV test was negative. CT head showed multiple lesions with surrounding edema thought to be septic emboli. CSF was consistent with WBC 278, RBC 59, Protein 130, Glucose 43. Necrotic mediastinal and hilar nodes were seen on CT chest. MRI brain revealed innumerable ring enhancing lesions with surrounding edema.Mediastinal lymph node biopsy revealed necrotising granulomas.Serum Histoplasma complement fixation titer was positive( 1:8)with a corresponding positive Histoplasma antibody by immunodiffusion.All other infectious workup was negative. A full immunological workup was normal.Patient was treated with liposomal amphotericin B for 4 weeks.Patient showed signs of clinical and radiological improvement and was discharged home on Iatraconazole . A repeat MRI of the brain at 8 weeks later showed significant improvement of the brain lesions.

DISCUSSION:

Disseminated histoplasmosis can occur in immune compromised states and rarely at extremes of age. [1] Only few cases of intracranial histoplasmosis have been reported in immune competent individuals [2] The findings in these cases were consistent with meningitis, focal lesions, stroke and never innumerable cystic lesions.Diagnosis is a challenge,with cases reporting chronic infections diagnosed several years later.[3] This case deserves attention ,for the sake of an exceedingly unusual presentation in a host where such infection is extremely uncommon; perhaps alluding to an underlying process yet to be characterized.

CONCLUSIONS:

Diagnosing disseminated Histoplasmosis with unusual presentation can be challenging in an immune competent adult.1) Goodwin R, Shapiro J, Thurman G, et al. Disseminated histoplasmosis: clinical and pathologic correlations. Medicine (Baltimore) 1980; 50:1-33.2) Berger J, Greenberg R. Isolated central nervous system histoplasmosis in an immunocompetent patient: 53-month hiatus to diagnosis and treatment. J Neurovirol 2010; 16(6): 472-4.3) Wheat L, Musial C, Jenny-Avital E. Diagnosis and Management of Central Nervous System Histoplasmosis. Clin Infect Dis 2005; 40(6): 844-52.DISCLOSURE: The following authors have nothing to disclose: Christopher Radchenko, Gurpreet Johal, Shais Jallu, Jason Mohr, Kush Tripathi, Abid BhatNo Product/Research Disclosure InformationUniversity of Missouri Kansas City, Kansas City, MO.

Mycotoxins are commonly present in cereal grains and are not completely destroyed during their cooking and processing. When mycotoxins contaminate staple foods, the risk for exposure becomes serious. In East Asia, including Japan, rice is consumed as a staple food, and with the increasingly Westernized lifestyle, the consumption of wheat has increased. The mycotoxins commonly associated with rice and wheat are total aflatoxin (AFL) and ochratoxin A (OTA), respectively. This study examined the retention of AFL and OTA during the cooking of rice and pasta. AFL was retained at 83%-89% the initial level after the cooking of steamed rice. In pasta noodles, more than 60% of the OTA was retained. These results show that AFL and OTA are relatively stable during the cooking process, suggesting that a major reduction in the exposure to these mycotoxins cannot be expected to occur by cooking rice and pasta. The estimated exposure assessment at the high consumer level (95th percentile) and the mycotoxin contamination level determined by taking into account these reductions in the present study should be useful for the establishment of practical regulations for mycotoxins in staple foods.

Maize (Zea mays L.), wheat (Triticum aestivum L.) and rice (Oryza sativa L.) are three staple crops and accordingly it is very meaningful to optimize the condition of their protoplasts isolation. The concentration of the enzyme, the time of isolation and centrifugal force in protoplast isolation were investigated to find their effects on protoplast yield and viability using leaves of maize (Zong 3), wheat (Chinese Spring) and rice (Nipponbare). The results show that the concentration of the enzyme and the time of isolation affected the protoplast yield significantly. Although the yield of protoplast was increased with high concentration of enzyme and long incubated time, it led to too much cells breakdown. The orthogonal experimental design results show that the best condition of maize protoplast isolation was Cellulase R-10 1.5%, Macerozyme R-10 0.5%, 50 r/min 7 h, 100 x g 2 min and the protoplasts yield was 7x106 cells/g fresh weight (FW); the best condition of wheat protoplast isolation was Cellulase R-10 1.5%, Macerozyme R-10 0.5%, 50 r/min 5 h, 100 x g 2 min and the protoplasts yield was 6 x 10(6) cells/g FW; the best condition of rice protoplast isolation was Cellulase R-10 2.0%, Macerozyme R-10 0.7%, 50 r/min 7 h, 1 000 x g 2 min and the protoplasts yield was 6x10(6) cells/g FW. The vitalities were more than 90% using fluorescein diacetate staining method. 50%-80% transformation efficiency was obtained when protoplasts were transformed by green fluorescent protein using PEG-Ca2+ method.

Adopting atomic absorption spectrometry (novAA400), the present study investigated the distribution characteristics of soil cadmium (Cd) in different textured paddy soil profiles under rice-wheat rotation and its correlation with Cd uptake by rice and wheat in Chengdu Plain through repeatedly taking soil and plant samples at the fixed sites in the field. The results revealed that Cd in the paddy soil profiles was mainly concentrated at the plough layer (0-15 cm) that obviously featured 'Cd accumulates towards the rooting layer'. Soil total Cd and available Cd (1 mol x L(-1) MgCl2 extraction) in the profile declined with soil depths and its average values at 30-45 cm only accounted for 47.60% and 39.49% of those at 0-15 cm. The potential downward movement of Cd in the different textured soil profiles was observed as sandy loam > heavy loam > loam. There was no significant correlation between soil pH and available Cd(r = - 0.46) at 0-15 cm soil depth, while significantly negative correlations between soil pH and available Cd were observed at 15-30 cm (r = -0.78) and 30-45 cm (r = -0.86). The results further demonstrated that the Cd contents in either grain or straw of rice and wheat were not well correlated with soil total Cd at any soil depth (r = -0.092-0.383 for rice and r = 0.174-0.424 for wheat), but significantly correlated with soil available Cd at 0-15 cm and at 15-30 cm (r = 0.766*-0.953**) despite insignificant correlation at 30-45 cm (r = 0.526-0.584). It is strongly suggested that the soil available Cd can be used as a better criterion than the total soil Cd to rate Cd contaminated soils in relation to safety of agricultural products.

Ecological theory predicts that fitness costs of herbicide resistance should lead to the reduced relative abundance of resistant populations upon the cessation of herbicide use. This greenhouse research investigated the potential fitness costs of two multiple herbicide resistant (MHR) wild oat (Avena fatua) populations, an economically important weed that affects cereal and pulse crop production in the Northern Great Plains of North America. We compared the competitive ability of two MHR and two herbicide susceptible (HS) A. fatua populations along a gradient of biotic and abiotic stresses The biotic stress was imposed by three levels of wheat (Triticum aestivum) competition (0, 4, and 8 individuals pot(-1)) and an abiotic stress by three nitrogen (N) fertilization rates (0, 50 and 100 kg N ha(-1)). Data were analyzed with linear mixed-effects models and results showed that the biomass of all A. fatua populations decreased with increasing T. aestivum competition at all N rates. Similarly, A. fatua relative growth rate (RGR) decreased with increasing T. aestivum competition at the medium and high N rates but there was no response with 0 N. There were no differences between the levels of biomass or RGR of HS and MHR populations in response to T. aestivum competition. Overall, the results indicate that MHR does not confer growth-related fitness costs in these A. fatua populations, and that their relative abundance will not be diminished with respect to HS populations in the absence of herbicide treatment.

Common wheat is a hexaploid species with most of the genes present as triplicate homoeologs. Expression divergences of homoeologs are frequently observed in wheat as well as in other polyploid plants. However, little is known about functional variances among homologous genes arising from polyploidy. Expansins play diverse roles in plant developmental processes related to the action of cell wall loosening. Expression of the three TaEXPA1 homoeologs varied dynamically at different stages and organs, and epigenetic modifications contribute to the expression divergence of three TaEXPA1 homoeologs during wheat development. Nevertheless, their functions remain to be clarified. We found that over expression of TaEXPA1-A, -B and -D produced similar morphological changes in transgenic Arabidopsis plants, including increased germination and growth rate during seedling and adult stages, indicating that the proteins encoded by these three wheat TaEXPA1 homoeologs have similar (or conserved) functions in Arabidopsis. Collectively, our present study provided an example of a set of homoeologous genes expression divergence in different developmental stages and organs in hexaploid wheat but functional retention in transgenic Arabidopsis plants.

Soil organic carbon (SOC) dynamics in Australian wheat-growing areas were simulated from 1960 to 2010 using Agro-C, a calibrated and validated biogeophysical model. Previously published data from field measurements were used to parameterize the Agro-C model. Model simulations show a decreasing trend in SOC over the last 50 years, mainly attributable to relatively low organic carbon (C) inputs. The rate of decrease in SOC tended to slow in the last two decades due primarily to an increase in wheat yields, which resulted in an increase in C input. Overall, we estimate that Australian wheat-growing areas, covering an area of 15.09 million hectares (Mha), lost 156 (86-222, 95% confidence interval) Tg C in the topsoil (to 30 cm depth) from 1960 to 2010. Approximately 80% of the SOC loss occurred in the period between the 1960s and the 1980s. Spatially, the SOC loss in areas with relatively high temperature and low precipitation, such as Queensland, the northern part of New South Wales and Western Australia, was more significant than that in other areas. We suggest that the loss of SOC could be halted, or even reversed, with an additional input of organic C into the soil at a minimum rate of 0.4 Mg ha(-1) yr(-1).

An extracellular haloalkaliphilic thermostable α-amylase producing archaeon was isolated from the saltwater Lake Urmia and identified as Halorubrum xinjiangense on the basis of morphological, biochemical, and molecular properties. The enzyme was purified to an electrophoretically homogenous state by 80 % cold ethanol precipitation, followed by affinity chromatography. The concentrated pure amylase was eluted as a single peak on fast protein liquid chromatography. The molecular mass of the purified enzyme was about 60 kDa, with a pI value of 4.5. Maximum amylase activity was at 4 M NaCl or 4.5 M KCl, 70 °C, and pH 8.5. The K m and V max of the enzyme were determined as 3.8 mg ml(-1) and 12.4 U mg(-1), respectively. The pure amylase was stable in the presence of SDS, detergents, and organic solvents. In addition, the enzyme (20 U) hydrolyzed 69 % of the wheat starch after a 2-h incubation at 70 °C in an aqueous/hexadecane two-phase system.

Previously, we identified more than 1,500 genes that were induced by high salt stress in sheepgrass (Leymus chinensis, Gramineae: Triticeae) when comparing the changes in their transcription levels in response to high salt stress by next-generation sequencing. Among the identified genes, a gene of unknown function (designated as Leymus chinensis salt-induced 1, LcSAIN1) showed a high sequence identity to its homologs from wheat, Hordeum vulgare and Oryza sativa, but LcSAIN1 and its homologs produce hypothetical proteins with no conserved functional domains. The LcSAIN1 gene transcription was up-regulated by various stresses. The over-expression of LcSAIN1 in Arabidopsis and rice increased the greening rate of cotyledons, the fresh weight, root elongation, plant height, and the plant survival rate when compared with control plants and conferred a tolerance against salt stress. Subcellular localization analysis indicated that LcSAIN1 is localized predominantly in the nucleus. Our results show that the LcSAIN1 gene might play an important positive modulation role in increasing the expression of transcription factors (MYB2 and DREB2A) and functional genes (P5CS and RAB18) in transgenic plants under salt stress and that it augments stress tolerance through the accumulation of compatible solutes (proline and soluble sugar) and the alleviation of ROS changes. The LcSAIN1 gene could be a potential resource for engineering salinity tolerance in important crop species.