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Abstract Background Treatment of acute myocardial infarction with stem cell transplantation has achieved beneficial effects in many clinical trials. The bone marrow microenvironment of ST-elevation myocardial infarction (STEMI) patients has never been studied even though myocardial infarction is known to cause an imbalance in the acid-base status of these patients. The aim of this study was to assess if the blood gas levels in the bone marrow of STEMI patients affect the characteristics of the bone marrow cells (BMCs) and, furthermore, do they influence the change in cardiac function after autologous BMC transplantation. The arterial, venous and bone marrow blood gas concentrations were also compared. Methods Blood gas analysis of the bone marrow aspirate and peripheral blood was performed for 27 STEMI patients receiving autologous stem cell therapy after percutaneous coronary intervention. Cells from the bone marrow aspirate were further cultured and the bone marrow mesenchymal stem cell (MSC) proliferation rate was determined by MTT assay and the MSC osteogenic differentiation capacity by alkaline phosphatase (ALP) activity assay. All the patients underwent a 2D-echocardiography at baseline and 4 months after STEMI. Results As expected, the levels of pO2, pCO2, base excess and HCO3 were similar in venous blood and bone marrow. Surprisingly, bone marrow showed significantly lower pH and Na+ and elevated K+ levels compared to arterial and venous blood. There was a positive correlation between the bone marrow pCO2 and HCO3 levels and MSC osteogenic differentiation capacity. In contrast, bone marrow pCO2 and HCO3 levels displayed a negative correlation with the proliferation rate of MSCs. Patients with the HCO3 level below the median value exhibited a more marked change in LVEF after BMC treatment than patients with HCO3 level above the median (11.13 ± 8.07% vs. 2.67 ± 11.89%, P = 0.014). Conclusions Low bone marrow pCO2 and HCO3 levels may represent the optimal environment for BMCs in terms of their efficacy in autologous stem cell therapy in STEMI patients.

Abstract Background Candida krusei infections are associated with high mortality. In order to explore ways to prevent these infections, we investigated potential routes for nosocomial spread and possible clonality of C. krusei in a haematological unit which had experienced an unusually high incidence of cases. Methods We searched for C. krusei contamination of the hospital environment and determined the level of colonization in patients and health care workers. We also analyzed the possible association between exposure to prophylactic antifungals or chemotherapeutic agents and occurrence of C. krusei. The C. krusei isolates found were genotyped by pulsed-field electrophoresis method in order to determine possible relatedness of the cases. Results Twelve patients with invasive C. krusei infection and ten patients with potentially significant infection or mucosal colonization were documented within nine months. We were unable to identify any exogenic source of infection or colonization. Genetic analysis of the isolates showed little evidence of clonal transmission of C. krusei strains between the patients. Instead, each patient was colonized or infected by several different closely related genotypes. No association between medications and occurrence of C. krusei was found. Conclusion Little evidence of nosocomial spread of a single C. krusei clone was found. The outbreak may have been controlled by cessation of prophylactic antifungals and by intensifying infection control measures, e.g. hand hygiene and cohorting of the patients, although no clear association with these factors was demonstrated.

The epidermal growth factor (EGF) is a molecule of potent mitogenic activity that accelerates the healing of wounds and ulcers of different tissues in the human body. Over the last years, some institutions of the Havana Western Scientific Pole in Cuba have been developing novel therapeutic products and projects using the human EGF (hEGF) like Heberprot-P® (CIGB) and Cimavax EGF® (CIM). Currently, the growing demand for this molecule has led to strategies being focused on a significant increase in the production capacity of the hEGF. The aim of this work was to increase productivity in the hEGF fermentation process by a combined study of physiological variables, cultivation media and bioreactor operation mode. The influence of culture medium components and the operation during fermentation on the homogeneous production of hEGF and the producer strain growth characteristics were evaluated. A 3.5-fold increase in EGF productivity was obtained by using high cell density fed-batch fermentation process. This fermentation process allowed reaching a cell concentration of 241.6 ± 18.8 g/L (wet mass) and hEGF production of 259.2 ± 37.2 mg/L. This is the first report of hEGF fermentation process expressed in yeasts with productivity of 4.82 ± 0.57 mg/L·h. As part of the analysis, we also discuss the impact of maintaining the highest hEGF expression on productivity in the fermentation process.

Manganese superoxide dismutase (MnSOD) protects cells against oxidative stress by eliminating superoxides. Hypothetically, decreased MnSOD levels in cancer might lead to increased oxidative stress and, thus, to increased sensitivity of cells to chemotherapy agents. Eighty-nine patients with acute myeloid leukemia (AML) were analyzed for a functional C to T polymorphism of MnSOD, which could potentially lead to decreased enzyme concentrations inside mitochondria. A significant survival advantage (p=0.02) was observed for those AML patients carrying T-containing alleles of MnSOD compared to the patients with the CC genotype. These preliminary results may indicate an important role for genetic factors regulating the cellular redox state in determining the outcome of leukemia chemotherapy.