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Mesenchymal stem cells (MSCs) are progenitors that are capable of differentiating into mesenchymal tissues. They are known to support allogeneic hematopoietic stem cell transplantation by facilitating engraftment without increasing the risk of graft-versus-host disease. We optimized culture conditions for human fetal liver-derived MSCs (hFL-MSCs) to investigate the role of hFL-MSCs on repopulation of hematopoietic stem cells in NOD/Shi-scid/IL-2Rγ(null) (NOG) mice using CD34(+) hematopoietic stem cells (HSCs) derived from umbilical cord blood (UCB). FL-MSCs and CD34(+) HSCs were prepared from fetal liver and UCB, respectively. Twenty-four hours after irradiation, CD34(+) HSCs and hFL-MSCs were injected intravenously and intratibially into NOG mice. During 24 weeks posttransplantation, engraftment levels of human cells were analyzed in bone marrow, peripheral blood, and spleen of transplanted mice by flow cytometry. hFL-MSCs showed a fibroblast-like morphology and immunophenotypic characteristics appropriate for MSCs. hFL-MSCs prolonged the survival of NOG mice that had been cotransplanted with UCB CD34(+) cells. Fluorescence-activated cell-sorting analysis showed that engraftment of human cells was increased by cotransplantation of hFL-MSCs. However, significant enhancement of human cell engraftment was not detected in NOG mice regardless of the number of cotransplanted MSCs. Although survival of repopulating NOG mice and engraftment of human cells were prolonged by cotransplantation of hFL-MSCs, 8.0 × 10(6) MSCs were not sufficient to increase HSC engraftment in irradiated NOG mice in vivo.

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INTRODUCTION: Nucleated red blood cell (NRBC) count is closely associated with the prognosis of neonates. The analysis of NRBC has traditionally been measured manually. Recently, a newly developed automated hematology analyzer, the UniCel DxH 800 (DxH 800), was released. The goal of our study was to evaluate the performance of the DxH 800 NRBC method in neonates with the reference manual method and against previous generation hematology analyzers. METHODS: NRBCs were counted in 162 neonatal blood samples using the DxH 800, LH 750, and ADVIA 2120 vs. the reference manual technique. The concordance rate, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were obtained. RESULTS: The DxH 800 showed an R(2) value of 0.945 and the concordance rate of 93.8%. Further assessment revealed 85.3% sensitivity, 96.1% specificity, 85.3% PPV, and 96.1% NPV, resulting in the highest area under the curve (0.961). The LH 750 and ADIVA 2120 demonstrated R(2) values of 0.851 and 0.529, respectively. CONCLUSION: The results obtained indicate the UniCel DxH 800 to be an excellent test on neonatal blood and superior to the other analyzers. Therefore, the DxH 800 is an effective and highly sensitive system for the analysis of NRBCs on newborns.

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A nested polymerase chain reaction (PCR) assay was developed for detection of Colletotrichum acutatum on symptomless strawberry leaves. In pure culture, the assay detected as little as 1.0 fg of DNA extracted from mycelium and as few as 1.5 conidia ml-1 when conidial suspensions were sonicated. On detached inoculated leaves, three alternative protocols to dislodge the pathogen were assessed: (i) immersion of whole leaves in 0.05% Tween 20 and manual agitation in plastic bags for 1 min (A); (ii) immersion in Tween 20, sonication for 30 min, then agitation for 1 min (SA); and (iii) freezing for 3 h, incubation for 2 days at 27°C, immersion in Tween 20, then sonication for 30 min and agitation for 1 min (FISA). Each method removed significantly (P ≤ 0.05) more conidia from leaves than the nontreated control; however, removal of appressoria did not vary among assays. In composite samples of noninoculated and inoculated (1.5 ×103 conidia ml-1) strawberry leaves, the nested PCR assay using the FISA protocol detected C. acutatum in as few as 1 infested leaf in 50 noninfested leaves. In a strawberry field, the assay detected the presence of C. acutatum in samples of asymptomatic strawberry leaves, showing potential as a powerful tool for reliable diagnosis of the pathogen in the field.

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Symptoms typical of anthracnose fruit rot; sunken, dark brown lesions on maturing fruits, were found in a commercial field of strawberry (Fragaria × ananassa) cv. Cal Giant in Yangyang County, Korea in May 2007. Masses of conidia were produced in acervuli in the center of lesions. The fungus was isolated on potato dextrose agar (PDA). Colonies grown on PDA were pale to mouse gray and became dark green to black in reverse. Conidia were formed in orange-to-salmon pink masses in the center of the culture. The average size of conidia on PDA was 15.2 × 4.6 µm, and they were hyaline, straight, cylindrical, with pointed ends, and aseptate (1). The fungus did not form an ascigerous stage in culture. Mycelial growth rate was 7.5 mm per day at 25°C on PDA. The identity of two isolates was confirmed as Colletotrichum acutatum J.H. Simmonds by PCR amplification using species-specific primers TBCA and TB5 (2), resulting in a characteristic 330-bp band on agarose gel. Morphological characters were in accordance with previous reports on C. acutatum. A pathogenicity test was conducted with five healthy plants of cvs. Cal Giant, Maehyang, Seolhyang, Kumhyang, Akihime, and Redpearl. After fruits and flowers were sprayed with a conidia suspension (105 conidia per ml), the plants were maintained at 10 to 25°C and 100% relative humidity in a greenhouse. As a control, five healthy plants were sprayed with sterile distilled water and incubated under the same conditions. Dark brown, water-soaked spots appeared on mature fruits of all cultivars after 5 days, and lesions on green fruits appeared on individual achenes. Flowers developed dark lesions, dried out, and died. No symptoms were found on the control plants. After the pathogen was reisolated from fruits and flowers lesions, the morphological characters developed in culture as described above. To our knowledge, this is the first report of C. acutatum causing strawberry anthracnose in Korea. References: (1) B. J. Smith and L. L. Black. Plant Dis. 74:69, 1990. (2) P. Talhinhas et al. Appl. Environ. Microbiol. 71:2987, 2005.

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Identification of the PCR markers tightly linked to genes that encode important agronomic traits is useful for marker-assisted selection (MAS). The rice Pi5(t) locus confers broad-spectrum resistance to Magnaporthe grisea, the causal agent of rice blast disease. It has been hypothesized that the Pi5(t) locus carries the same gene as that encoded by the Pi3(t) and Pii(t) loci. We developed three PCR-based dominant markers (JJ80-T3, JJ81-T3, and JJ113-T3) from three previously identified BIBAC clones-JJ80, JJ81, and JJ113-that are linked to the Pi5(t) locus. PCR analysis of 24 monogenic lines revealed that these markers are present only in lines that carry Pi5(t), Pi3(t), and Pii(t). PCR and DNA gel-blot analysis of candidate resistance lines using JJ80-T3, JJ81-T3, and JJ113-T3 indicated that Tetep is the likely donor of Pi5(t). Of the 184 rice varieties tested, 34 carried the JJ80-T3-, JJ81-T3-, and JJ113-T3-specific bands. Disease evaluation of those 34 varieties revealed that all conferred resistance to PO6-6. The genomic structure of three of these resistant varieties (i.e., IR72, Taebaeg, Jahyangdo) is most similar to that of Pi5(t). Our results demonstrate the usefulness of the JJ80-T3, JJ81-T3, and JJ113-T3 markers for MAS for M. grisea resistance.

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A rare case of pericardial tamponade developed in a 69-year-old man after a right upper lobectomy for lung cancer. This unusual complication presented in the early postoperative period and was associated with what we believed to be an aberrant right bronchial artery coming off the intrapericardial portion of the aorta. This vessel retracted into the pericardial sac where it bled causing a pericardial tamponade.

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Giant cell arteritis is often considered less common in African Americans. In 1985, we reviewed 34 African American patients with biopsy-proven temporal arteritis. We report on 9 additional biopsy positive patients seen at the Washington Hospital Center (WHO between 1988 and 1996.Clinical presentations were similar to those reported in previous series, with the exception that only one patient had polymyalgia rheumatica. Two patients had visual symptoms, but only one patient had permanent monocular visual loss. In combining our 9 new patients with 41 biopsy-proven, well characterized, published patients and comparing them with a representative Caucasian group, we found statistically significant differences. Male gender, anemia, and visual loss were overall more common in African Americans, whereas constitutional symptoms and polymyalgia rheumatica were less common. The detection rate of temporal artery biopsies at WHC was lower than rates reported in other studies, but they did not differ by race.We conclude that giant cell arteritis should be pursued as a diagnosis in all patients presenting with appropriate clinical features, regardless of race, and that earlier recognition may account for the lower incidence of permanent visual loss.

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Pericarditis is one of the most frequent manifestations of systemic lupus erythematosus; however, purulent pericarditis and tamponade are rare. We describe a patient with systemic lupus erythematosus and culture-proven gonococcal arthritis who developed purulent pericarditis with intracellular gram-negative diplococci. Evidence of tamponade was seen on echocardiography. There has not been a reported case of Neisseria gonorrhoeae in pericardial fluid or tissue since the introduction of antibiotics.

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In small cell lung carcinoma, one of the short arms of chromosome 3 is typically lost. To investigate chromosome 3 in extrapulmonary small cell carcinoma, we used DNA probes that detect restriction-fragment-length polymorphisms at loci on 3p. These probes were used to study DNA extracted from tumors and normal tissues and/or tumor cell lines from five patients with extrapulmonary small cell cancer. Tumor DNA from four of the five patients with extrapulmonary small cell cancer retained heterozygosity at loci on 3p. Cytogenetic studies of the tumor cell lines established from these four patients showed retention of both short arms of chromosome 3. We conclude that the loss of genetic material from 3p observed in small cell lung cancer is not typical in extrapulmonary small cell cancer.

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Accumulation of phagocytic histiocytes with a foam cell morphology has been described in a number of diseases. Familial hypercholesterolemia, one such disease, is characterized by foamy histiocytic accumulation in cutaneous or tendinous xanthomas and within atheromatous lesions. This report describes a patient with familial hypercholesterolemia who had two unusual manifestations of foamy histiocytic accumulation: a maxillary sinus xanthoma, which presented as an expansile mass, and diffuse bone marrow replacement with foamy histiocytes, which was associated with myelophthisic anemia. The accumulation of foamy cells in both locations resembled that seen in many of the storage diseases. The possibility of foamy histiocytic accumulation should be considered in the differential diagnosis of patients with these disease entities who present with space-occupying lesions.

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