First Report of Endophytic Candida ipomoeae Isolated from Ovules of Upland Cotton in Mississippi

Cotton is grown on approximately 34.5 million ha worldwide to provide fiber, food oil, and animal feed. To our knowledge, this report is the first of Candida ipomoeae on cotton, and this yeast was found on ovules of the most commercially important cotton species in a major cotton-growing region. The yeast was isolated from ovules of upland cotton grown in vitro. A culture (NRRL Y-48065) was sent to Microbial ID Inc. (Newark, DE) where a partial 176-bp sequence for the D2 domain of the large subunit rDNA was obtained. A BLAST search on the GenBank database ( www.ncbi.nih.gov/Genbank/index.html ) found a 100% match between our sequence and accessions from two strains of C. ipomoeae (Accession Nos. AF050148 and AF050149). In addition, the distinctive colony morphology (white pseudomycelium with a raised stellate to lobate edge) was consistent with previous descriptions of C. ipomoeae (1). No growth was observed at 37°C for the current and previously described isolates. C. ipomoeae is a recently described asexual species (1) that has been isolated from morning glory (Ipomoea spp.) flowers and their insect visitors in Hawaii and the Americas (2). C. ipomoeae has also been found on insects that have visited flowers of the indigenous wild Hawaiian cotton species, Gossypium tomentosum (2) but it has not been isolated previously from cotton per se. Endogenous microbes are common in field-grown upland cotton and can be an impediment to obtaining aseptic plant tissue cultures. During August and September 2005, as part of an effort to rescue interspecific cotton hybrids, ovules were cultured in vitro for 4 days after pollination from plants grown in a field at Stoneville, MS. Fruit were washed in soap and water, surface sterilized in a laminar flow hood by immersion in an aqueous solution of 2.6% sodium hypochlorite and 0.1% Tween 20 for 10 min with intermittent shaking, followed by immersion in ethanol for 10 min, and then allowed to air dry. This surface sterilization protocol is >99% effective on greenhouse-grown fruit. For each fruit, ovules were placed on a single 100 × 25-mm petri dish containing 25 ml of modified Murashige and Skoog media with Gambourg's B5 vitamins (M0404; Sigma-Aldrich, St. Louis, MO) plus 1.9 g l^-1 KNO₃, 0.5 g l^-1 asparagine, 1.0 g l^-1 glutamine, 20.0 g l^-1 glucose, 0.25 g l^-1 cefotaxime, and 2.2 g l^-1 gelrite, with a pH of 5.8. Plated ovules were incubated at 30°C with 12 h of fluorescent light each day. C. ipomoeae was first observed on ovules of the cv. Deltapine 90 crossed with G. arboreum; other fungal contaminants were also observed but all of these contaminants originated from ovules within 2 weeks of culture, indicating that the contaminants were endogenous. Subsequently, ovules from the self-pollination of cv. FiberMax 832 were grown on media containing 50 mg l^-1 benomyl. On the benomyl-containing plates, the only fungal contaminant observed was C. ipomoeae and it was found on 22 of 120 plates. On plates with or without benomyl, C. ipomoeae grew slowly but caused the infected ovules to become necrotic and die, in contrast to uninfected ovules. Over time, the cultured ovules were completely overrun by the C. ipomoeae colonies. By identifying the contaminant as C. ipomoeae, pursuit of a targeted strategy for controlling it in cotton tissue cultures will now be possible. References: (1) M. A. Lachance et al. Can J. Microbiol. 44:718, 1998. (2) M. A. Lachance et al. FEMS (Fed. Eur. Microbiol. Soc.) Yeast Res. 1:1, 2001.

Evaluation of an aviator with chronic disequilibrium, oscillopsia, and central sleep apnea

A case is presented of an aviator with chronic disequilibrium, oscillopsia, and central sleep apnea. History, physical examination, and special studies are presented establishing a diagnosis of epidermoid tumor at the foramen magnum. Differential diagnosis and relation of findings to the lesion are presented. The aeromedical significance of this case is to reinforce the importance of persistence and the team concept in establishing diagnoses when aviators present with confusing or unexplained symptoms.

Esmolol (Brevibloc) to assess dynamic subpulmonary stenosis in a child after repair of complete transposition: a case report

Esmolol (Brevibloc), a new, ultra-short acting, cardioselective beta-adrenergic blocking agent with half-life of 9.2 min following i.v. administration was given to a 4-year-old child with known dynamic and fixed sub-pulmonary stenosis post Senning repair for complete transposition of the great vessels. The left ventricular systolic pressure increased from 48 to 100 mmHg, heart rate showed an increase from 65 to 140 bpm, the right femoral arterial pressures decreased from 115/58 to 77/35 mmHg following an infusion of Isoprel. Infusion of esmolol partially relieved the dynamic sub-pulmonary stenosis. There were no adverse effects and esmolol was tolerated well by the child. Esmolol might thus play a role in the pediatric catheterization laboratory during investigational procedures, electrophysiological studies and in the control of rapid supraventricular tachycardia, especially in adolescents with WPW pre-excitation. Esmolol would also be beneficial in emergency treatment of epinephrine or isoproterenol overdosage.

Ectopic automatic atrial tachycardia in children: clinical characteristics, management and follow-up

Ectopic automatic atrial tachycardia, an uncommon type of supraventricular tachycardia in children and adults, has been reported to be resistant to medical therapy, and surgical or cryoblation has been recommended. This report describes 10 infants and children (median age 6 months; range birth to 7.5 years) with automatic atrial tachycardia and their management and follow-up. Digoxin alone was unsuccessful in controlling tachycardia in all 10 patients but decreased the tachycardia rate by 5 to 20% in 8. Intravenous (0.1 mg/kg body weight per dose) and oral propranolol successfully suppressed tachycardia in three of five patients and oral propranolol successfully controlled tachycardia in two of five other patients. Class I antiarrhythmic agents--quinidine (three patients), procainamide (four patients) and phenytoin (three patients)--did not control tachycardia in any patients but made the tachycardia rate worse in three patients. Intravenous (5 mg/kg per dose) and oral amiodarone suppressed tachycardia in three of four patients and oral amiodarone suppressed it in another patient. Thus, intravenous propranolol and amiodarone were effective in acutely suppressing automatic ectopic atrial tachycardia and predicted the response to long-term oral therapy. One patient had persistent tachycardia after surgical ablation of the high right atrial ectopic focus, and another patient had unsuccessful catheter ablation of the high right atrial ectopic focus (25 J). During follow-up (10 to 28 months), ectopic atrial tachycardia resolved completely in four patients and was well controlled in four patients.

Pulmonary venoocclusive disease: case report and review of the literature

A fatal case of pulmonary venoocclusive disease in a 4-year-old boy is reported, with emphasis on the radiologic features of this condition. The disease is characterized by fibrous intimal obliteration of the lumina of small pulmonary veins and venules leading to severe secondary pulmonary arterial hypertension. The clinical picture is usually indistinguishable from that of other forms of pulmonary arterial hypertnesion, but radiologic features of postcapillary pulmonary hypertension, in conjunction with a normal venoocclusive disease. The diagnosis is definitively established by lung biopsy.