First Report of Leaf Rust of Blueberry Caused by Pucciniastrum vaccinii in Hawaii

Blueberries (Vaccinium corymbosum L.) are a potential high-value, niche market crop for Hawaii. In May of 2007, rust-like symptoms were observed on multiple blueberry plants in a private nursery in Waimea, HI. In September of 2007, a similar leaf rust was observed on one bush of V. corymbosum cv. Sharpblue in the corner of a 36.6 × 9.1-m experimental plot at Mealani Research Station in Waimea. Within a month, rust was observed throughout the plot on 'Biloxi', 'Emerald', 'Jewel', 'Misty', 'Sapphire', and 'Sharpblue'. Preliminary field observations suggest that 'Sharpblue' and 'Sapphire' are highly susceptible to the rust and 'Biloxi' shows some tolerance. Leaf lesions began as approximately 1-mm² chlorotic flecks that expanded and developed into reddish brown, necrotic spots with a chlorotic halo. New lesions and uredinia kept appearing over the course of 4 months. Defoliation occurred on plants where infection was severe. Yellowish orange pustules containing urediniospores first appeared on the abaxial side of older leaves and later appeared on new leaves. Urediniospores were elliptical to obovate (19.4 to 24.8 × 15.2 to 19.8 μm) with a thick, slightly roughened wall and a well-developed pore. Urediniospore morphology and dimensions were consistent with the description of Pucciniastrum vaccinii (G. Wint.) (1). A pathogenicity test was conducted with two 18-month-old 'Sharpblue' plants. Fully expanded leaves were sprayed with freshly collected urediniospores (3.8 × 10⁵ spores per ml) suspended in a 0.05% solution of Tween 20 in water. The control plant was sprayed with sterile distilled water (SDW). Plants were covered with plastic bags for 48 h and held in a growth chamber at 20 to 22°C under continuous fluorescent lighting. The plastic bags were then removed and the plants were maintained in the growth chamber. Yellowish orange pustules that were identical to the original symptoms developed on 100% of inoculated leaves after 10 days. The plant inoculated with SDW remained symptomless. While leaf rust caused by P. vaccinii has been reported on Ohelo berry (V. reticulatum) (2), it has not been reported on V. corymbosum in Hawaii. To our knowledge, this is the first report of P. vaccinii on blueberry plants in Hawaii. This rust disease may pose a threat to the potential blueberry industry in Hawaii. References: (1) P. R. Bristow and A. W. Stretch. Page 20 in: Compendium of Blueberry and Cranberry Diseases. F. L. Caruso and D. C. Ramsdell, eds. The American Phytopathological Society, St. Paul, MN, 1995. (2) D. F. Farr et al. Fungal Databases. Systematic Botany and Mycology Laboratory. Online publication. ARS, USDA, 2008.

[Apical ballooning by transient left ventricular dysfunction (so-called "ampulla" cardiomyopathy) associated with therapy for acute pulmonary thromboembolism: a case report]

An 86-year-old-woman presented with apical ballooning left ventricular dysfunction associated with therapy for acute pulmonary thromboembolism. She was referred to our hospital for advanced treatment for her shock state due to acute pulmonary embolism with normal left ventricular(LV) function. Her condition was stabilized using a percutaneous cardiopulmonary support system. Suction embolectomy was successfully carried out after pulmonary arteriography. After the therapy, echocardiography revealed apical ballooning and hyperkinesis of the base(LV ejection fraction = 28%), although coronary arteriography showed no fixed stenosis. LV wall motion significantly improved on day 3(LV ejection fraction = 45%). Pulmonary embolism relapsed on day 5 in spite of anticoagulation treatment. She died of multiple organ failure on day 9. Autopsy findings indicated no sign of myocardial infarction or myocarditis, patchy appearance of myocardial contraction band necrosis and few migrated lymphocytes. The mechanism for the flow mis-matched LV dysfunction remains unknown. The probable explanations include non-ischemic stress such as catecholamine or neurogenic stress, and possibly ischemic stress or ischemia/reperfusion injury.

Transient left ventricular apical ballooning without coronary artery stenosis: a novel heart syndrome mimicking acute myocardial infarction. Angina Pectoris-Myocardial Infarction Investigations in Japan

OBJECTIVES

To determine the clinical features of a novel heart syndrome with transient left ventricular (LV) apical ballooning, but without coronary artery stenosis, that mimics acute myocardial infarction, we performed a multicenter retrospective enrollment study.

BACKGROUND

Only several case presentations have been reported with regard to this syndrome.

METHODS

We analyzed 88 patients (12 men and 76 women), aged 67 +/- 13 years, who fulfilled the following criteria: 1) transient LV apical ballooning, 2) no significant angiographic stenosis, and 3) no known cardiomyopathies.

RESULTS

Thirt-eight (43%) patients had preceding aggravation of underlying disorders (cerebrovascular accident [n = 3], epilepsy [n = 3], exacerbated bronchial asthma [n = 3], acute abdomen [n = 7]) and noncardiac surgery or medical procedure (n = 11) at the onset. Twenty-four (27%) patients had emotional and physical problems (sudden accident [n = 2], death/funeral of a family member [n = 7], inexperience with exercise [n = 6], quarreling or excessive alcohol consumption [n = 5] and vigorous excitation [n = 4]). Chest symptoms (67%), electrocardiographic changes (ST elevation [90%], Q-wave formation [27%] and T-wave inversion [97%]) and elevated creatine kinase (56%) were found. After treatment of pulmonary edema (22%), cardiogenic shock (15%) and ventricular tachycardia/fibrillation (9%), 85 patients had class I New York Heart Association function on discharge. The LV ejection fraction improved from 41 +/- 11% to 64 +/- 10%. Transient intraventricular pressure gradient and provocative vasospasm were documented in 13/72 (18%) and 10/48 (21%) of the patients, respectively. During follow-up for 13 +/- 14 months, two patients showed recurrence, and one died suddenly.

CONCLUSIONS

A novel cardiomyopathy with transient apical ballooning was reported. Emotional or physical stress might play a key role in this cardiomyopathy, but the precise etiologic basis still remains unclear.

The intrinsic rhythmicity of spike-burst generation in pancreatic beta-cells and intercellular interaction within an islet

The pancreatic beta-cell has four types of Ca2+ channel (L-type, T-type, low-threshold slowly inactivating, and low-threshold non-inactivating Ca2+), although the low-threshold non-inactivating Ca2+ channel has not yet been confirmed experimentally. Beside these, there are at least three types of K+ channels (K(ATP), K(Ca,V), and K(V)), and transporters (GLUT-2, Na+/Ca(2+)-countertransporter, and Na+/K(+)-pump) as schematically shown in Fig.4. Opinions on the mechanism of spike-burst are converging to the following view: At intermediate glucose concentrations, the intracellular ATP/ADP ratio oscillates in the following way. A gradual rise in the ATP/ADP ratio causes gradual progression of depolarization to the threshold for the low-threshold Ca2+ channels, of which the opening causes regenerative depolarization to the plateau potential on which spikes (the L-type Ca2+ channel contributes to spike firing) are superimposed. During the active phase, a fall in the ATP/ADP ratio follows a gradual rise in ATP consumption. Slight repolarization due to the opening of a small fraction of K(ATP) channels triggers regenerative repolarization. With the progress of repolarization, a residual fraction of voltage-gated Ca2+ channels (low-threshold non-inactivating) are deactivated. During the silent phase, a gradual rise in the ATP/ ADP ratio leads to gradual depolarization back to the threshold for the next spike-burst. There are still a diversity of views regarding the mechanism of the initial spike-train. On the basis of observations made in various laboratories including ours, we propose the following working model: At low concentrations of glucose, alpha-cells secret glucagon which induces a rise in cAMP in beta-cells lodged in the same islet. A rise in cAMP itself does not activate the enzymes relevant to glycogenolysis, but merely prepares to activate the enzymes. When extracellular glucose increases, Ca2+ spikes are elicited. Influxed Ca2+ ions, together with cAMP, work to activate the enzymes, resulting in an additional supply of fuel for ATP synthesis. After sometime, the cAMP level falls back to a low level and the additional glucose supply from stored glycogen stops. This reaction sequence may be the mechanism behind the initial spike-train. To substantiate this working model, it may be important to elucidate the dependence of the phosphorylasekinase and glycogenphosphorylase activities on the Ca2+ in beta-cells.

[123I-MIBG myocardial SPECT in two patients with familial amyloid polyneuropathy]

201T1C1 SPECT and 123I-MIBG SPECT were performed in two patients with familial amyloid polyneuropathy (FAP). Both patients showed normal accumulation of 201T1C1 and no accumulation of 123I-MIBG in the myocardium at the early and delayed images. These results indicate that the patient with FAP-related myocardial change accompanies sympathetic nerve dysfunction. The dysfunction is supposed to be caused by disturbance of re-uptake of MIBG by the terminal ending of the sympathetic nerve (uptake-1) through the amyloid-deposited connective tissue.

Adhesion molecules on eosinophils in acute eosinophilic pneumonia

We describe the clinical features, eosinophil surface analysis, and concentration of interleukin-5 (IL-5) in bronchoalveolar lavage (BAL) and in peripheral blood (PB) of a young male patient with acute eosinophilic pneumonia. Eosinophilic pneumonia was diagnosed by BAL and by its clinical course. There was no evidence of an infectious etiology, and the patient showed rapid improvement with methylprednisolone pulse therapy (1 gm/d for 3 d). Significant differences in the expression of surface molecules such as CD54, HLA-DR, and CD69 were observed between BAL and PB eosinophils; IL-5 concentrations in BAL and in PB before treatment were 450 pg/ml and 700 pg/ml, respectively. After treatment, IL-5 concentration in PB was reduced to below 100 pg/ml. The patient has shown no recurrence after treatment.

Effects of lowering external Na+ concentration on cytoplasmic pH and Ca2+ concentration in mouse pancreatic beta-cells: mechanism of periodicity of spike-bursts

The periodic spike-burst response of pancreatic beta-cells varies in duration with an increase of external glucose within the range 5-20 mM. To elucidate the mechanism determining the length of spike-burst, we studied the low-Na+ induced change in electrical response to glucose which is similar to the change induced by high glucose. Cytoplasmic pH (pHi) and Ca2+ concentration ([Ca2+]i) were measured by the microfluorometric method under normal and low-Na+ conditions in mouse pancreatic islets. Lowering external Na+ concentration from 135 to 25 mM by replacing Na+ with Tris+ induced progressive alkalinization in islet cells in the presence of 11.1 mM glucose. In contrast, reduction of external Na+ by replacement with Li+ caused intracellular acidification. Both manipulations described above caused a marked increase in [Ca2+]i, suggesting the presence of Na+/Ca(2+)-antiport activity. Although the change in pHi induced by decreasing external Na+ varied in direction depending on the species of cations used for replacing Na+, the pattern of electrical activity consistently changed from the spike-burst type to the continuous spike-generation type without regard for the difference in species of cations replacing Na+. These findings lead to the following hypothesis: A decrease in Na+ influx could cause a decrease in ATP-consumption by Na+/K(+)-pumps that prevents the fall of intracellular ATP concentration. The resultant continuation of high concentrations of intracellular ATP may be responsible for the abolishment of the silent phase.

Isolation and characterization of the active cDNA of the human cell cycle gene (RCC1) involved in the regulation of onset of chromosome condensation

The human RCC1 gene was cloned after DNA-mediated gene transfer into the tsBN2 cell line, which shows premature chromosome condensation at nonpermissive temperatures (39.5-40 degrees C). This gene codes for a 2.5-kb poly(A)+ RNA that is well conserved in hamsters and humans. We isolated 15 cDNA clones from the Okayama-Berg human cDNA library, and found two that can complement the tsBN2 mutation with an efficiency comparable to that of the genomic DNA clone. The base sequences of these two active cDNA clones differ at the 5' proximal end, yet both have a common open reading frame, encoding a protein of 421 amino acids with a calculated molecular weight of 44,847 and with seven homologous repeated domains of about 60 amino acids. This human RCC1 gene was located to human chromosome 1 using sorted chromosomal fractions.

Molecular cloning of a human gene that regulates chromosome condensation and is essential for cell proliferation

The tsBN2 cell line, a temperature-sensitive (ts) mutant of baby hamster kidney cell line BHK21/13, seems to possess a mutation in the gene that controls initiation of chromosome condensation. At the nonpermissive temperature (39.5 degrees C), the chromatin of tsBN2 cells is prematurely condensed, and the cells die. Using tsBN2 cells as a recipient of DNA-mediated gene transfer, we investigated a human gene that is responsible for regulation of chromosome condensation and cell proliferation. We found that the human gene complementing the tsBN2 mutation resides in the area of the 40- to 50-kilobase HindIII fragment, derived from HeLa cells. Based on this finding, we initiated cloning of a human gene complementing the tsBN2 mutation. From lambda and cosmid libraries carrying partial digests of DNA from the secondary transformants, the 41.8-kilobase HindIII fragment containing the human DNA was isolated. The cloned human DNA was conserved in ts+ transformants through primary and secondary transfections. Two cosmid clones convert the ts- phenotype of tsBN2 cells to ts+ with more than 100 times a higher efficiency, compared with cases of transfection with total human DNA. Thus, the cloned DNA fragments contain an active human gene that complements the tsBN2 mutation.

Transformation of temperature-sensitive growth mutant of BHK21 cell line to wild-type phenotype with hamster and mouse DNA

A temperature-sensitive (ts) mutant, tsBN2, which was derived from BHK21 and is defective in the regulatory mechanism for chromosome condensation, was transformed to the temperature-resistant (ts+) phenotype by means of DNA-mediated gene transfer with hamster and mouse DNA. Treatment of mouse DNA with the restriction enzymes EcoRI, HindIII, PstI and SalI, but not with XhoI, almost completely abolished the transforming activity. A fluctuation test, originally devised by Luria and Delbrück, was used to estimate the reversion and transformation frequencies of tsBN2 cultures.

Recovery of a hybrid vector, derived from bovine papilloma virus DNA, pBR322 and the HSV tk gene, by bacterial transformation with extrachromosomal DNA from transfected rodent cells

A bovine papilloma virus (BPV)-pBR322-derived recombinant plasmid carrying a 2-kb fragment of Herpes simplex virus DNA containing the thymidine kinase (tk) gene is capable of transforming tk- cells of mouse L and Syrian hamster BHK21 lines to tk+. In transformed cells a small proportion of the plasmid DNA is present as extrachromosomal elements while the remainder appears to be integrated into the genome. It was possible to recover plasmids indistinguishable from the input DNA by transformation of Escherichia coli bacteria with low-molecular-weight DNA isolated from the transformed mouse and hamster cells and consisting of BPV-pBR322-HSV tk+ plasmids.

Large-scale selection and analysis of temperature-sensitive mutants for cell reproduction from BHK cells

Temperature-sensitive (ts) mutant cells for cell reproduction were isolated from the Syrian hamster cell line BHK21/13 by multiple culturing in the presence of 5-fluoro-2'-deoxyuridine (FdU) at 37.5 degrees after N-methyl-N'-nitro-N-nitrosoguanidine mutagenesis. A simple method for cell fusion was devised, which enabled us to perform complementation studies with a large number of ts mutants. By using the method we have analyzed 219 ts mutants and classified them into 18 complementation groups. Mutants that belonged to the same complementation groups tended to exhibit similar patterns of inhibition of DNA synthesis at 39.5 degrees; however, some mutants belonging to the same group showed somewhat different patterns, probably due to occurrence of different mutations in the same gene. Distribution of the ts mutants among the 18 complementation groups was uneven; more than 50% of the mutants examined were assigned to complementation group B and G. The mutations belonging to complementation group B and G were found to be linked to the X chromosome.