Clinical features and risk factors for mortality in Aeromonas bacteremic adults with hematologic malignancies.

BACKGROUND AND PURPOSE: Aeromonas spp. often cause infections in immunocompromised patients. To specifically understand the clinical features of Aeromonas bacteremic adults with hematologic malignancies, we investigated the demographic, clinical and microbiologic characteristics of Aeromonas bacteremia in this patient population. METHODS: Retrospective study performed in a tertiary medical center in southern Taiwan, in which adults with hematologic malignancies suffered from Aeromonas bacteremia admitted between 1995 and 2003 were included for study. RESULTS: There were 45 episodes of Aeromonas bacteremia in 41 adults with hematologic malignancies. Episodes of Aeromonas bacteremia which occurred at least 2 months apart were counted as separate cases in the analysis. A total of 30 men and 15 women (mean age: 53.2 years), with 4 patients experiencing 2 episodes, was included. The 3 leading underlying hematologic malignancies were acute myelogenous leukemia (37.8%), myelodysplastic syndrome (26.7%) and non-Hodgkin's lymphoma (17.8%). No cluster of Aeromonas bacteremia was found during the study period. Twenty nine (64.4%) of the 31 patients with nosocomial Aeromonas bacteremia had received recent antineoplastic chemotherapy. The 3 leading clinical manifestations were fever (88.9%), septic shock (40%), and altered consciousness (26.7%). Eleven (24.4%) episodes of bacteremia were polymicrobial. Sixteen (35.6%) patients died within 14 days of onset of bacteremia. The mean duration from sampling blood for culture to death was 3.81 days. Altered consciousness (odds ratio, 8.999; 95% confidence interval, 1.787-45.33; p=0.008) was the only independent prognostic factor for mortality. High resistance rates (11.1% to piperacillin and 35.6% to imipenem) among Aeromonas isolates were also noted. CONCLUSION: In febrile patients with hematologic malignancies and suspected Aeromonas infections, particular attention to the development of alteration of consciousness is needed as it is an independent risk factor for mortality.     

Screening for cognitive impairment in older adults attending an eye clinic

PURPOSE: We conducted a cross-sectional study examining potentially modifiable factors associated with cognitive impairments (mild or severe) in older whites, African Americans and Hispanics attending an outpatient eye clinic. METHODS: In-clinic interviews and physical examinations assessed social, demographic and health information from 100 consecutive Hispanic, African-American and white adults aged > or = 55. Our primary outcome was presence of any cognitive impairment (mild or severe) using the St. Louis University Mental Status Examination (SLUMS) scale. RESULTS: Of the 100 subjects, 65 screened positive for cognitive impairments on the SLUMS cognitive instrument: 46 with mild cognitive impairment and 19 with severe impairment (possible dementia). African-American and Hispanic adults (nonwhites) were significantly more likely to have cognitive impairment compared to white adults (OR 2.80: 95% CI = 1.05-7.44), independent of age, years of education and systolic blood pressure. Subjects with diabetes also had increased odds of cognitive impairments (OR 3.28, 95% CI = 1.21-8.90) even after adjusting for relevant confounders. There was a nonsignificant trend between visual acuity impairment and cognitive impairment (p = 0.059). CONCLUSIONS: Sixty-five percent of adults aged > or = 55 attending the eye clinic screened positive for cognitive impairments, with higher rates among nonwhites and adults living with diabetes.     

Effect of Group A Streptococcal Cysteine Protease on Invasion of Epithelial Cells

Cysteine protease of group A streptococci (GAS) is considered an important virulence factor. However, its role in invasiveness of GAS has not been investigated. We demonstrated in this study that two strains of protease-producing GAS had the ability to invade A-549 human respiratory epithelial cells. Isogenic protease mutants were constructed by using integrational plasmids to disrupt the speB gene and confirmed by Southern hybridization and Western immunoblot analyses. No extracellular protease activity was produced by the mutants. The mutants had growth rates similar to those of the wild-type strains and produced normal levels of other extracellular proteins. When invading A-549 cells, the mutants had a two- to threefold decrease in activity compared to that of the wild-type strains. The invasion activity increased when the A-549 cells were incubated with purified cysteine protease and the mutant. However, blockage of the cysteine protease with a specific cysteine protease inhibitor, E-64, decreased the invasion activity of GAS. Intracellular growth of GAS was not found in A-549 cells. The presence or absence of protease activity did not affect the adhesive ability of GAS. These results suggested that streptococcal cysteine protease can enhance the invasion ability of GAS in human respiratory epithelial cells.     

Ionically crosslinked alginate hydrogels as scaffolds for tissue engineering: part 1. Structure, gelation rate and mechanical properties

Alginate gels have been used in both drug delivery and cell encapsulation applications in the bead form usually produced by dripping alginate solution into a CaCl2 bath. The major disadvantages to these systems are that the gelation rate is hard to control; the resulting structure is not uniform; and mechanically strong and complex-shaped 3-D structures are difficult to achieve. In this work controlled gelation rate was achieved with CaCO3-GDL and CaSO4-CaCO3-GDL systems, and homogeneous alginate gels were formulated as scaffolds with defined dimensions for tissue engineering applications. Gelation rate increased with increasing total calcium content, increasing proportion of CaSO4, increasing temperature and decreasing alginate concentration. Mechanical properties of the alginate gels were controlled by the compositional variables. Slower gelation systems generate more uniform and mechanically stronger gels than faster gelation systems. The compressive modulus and strength increased with alginate concentration, total calcium content, molecular weight and guluronic acid (G) content of the alginate. MC3T3-E1 osteoblastic cells were uniformly incorporated in the alginate gels and cultured in vitro. These results demonstrated how alginate gel and gel/cell systems could be formulated with controlled structure, gelation rate, and mechanical properties for tissue engineering and other biomedical applications.     

Histiocytoid hemangioma of the heart with peripheral eosinophilia

A histiocytoid hemangioma of the heart is reported, which was found incidentally in a man with unusually high eosinophilia. The eosinophilia subsided dramatically following removal of the tumor. The "histiocytoid" or the "epithelioid" appearance of the tumor cells and the presence of vacuolated cells were the characteristic microscopic features. The endothelial origin of this tumor was verified by positive immunostaining for factor VIII-related antigen and ultrastructural demonstration of intracytoplasmic lumen formation, abundant cytoplasmic filaments, pinocytotic vesicles, and prominent basal lamina. The presence of mitotic activity, cellular pleomorphism, and tumor necrosis raised the possibility of its malignant potential. The occurrence of this tumor in the heart may be mistaken for a myxoma clinically and a metastatic carcinoma pathologically.