High-resolution MRI vs multislice spiral CT: which technique depicts the trabecular bone structure best?

The purpose of this study was to compare trabecular bone structure parameters obtained from high-resolution magnetic resonance (HRMR) and multislice computed tomography (MSCT) images with those determined in contact radiographs from corresponding specimen sections. High-resolution MR and MSCT images were obtained in 39 distal radius specimens. For HRMR the in-plane spatial resolution was 0.152×0.153 mm² with a slice thickness of 0.9 and 0.3 mm using a 3D T1-weighted spin-echo sequence. For MSCT the resolution was 0.247×0.247 mm² with a collimation of 1 mm. Using a diamond saw, 117 0.9- to 1-mm-thick sections were obtained from these specimens and contact radiographs were acquired. In the corresponding sections structure parameters analogous to bone histomorphometry were determined. Significant correlations between MR- and CT-derived structure parameters and those derived from the contact radiographs were found (p<0.01); r values of up to 0.75 were obtained for HRMR imaging and up to 0.70 for MSCT. On the average, structure parameters showed higher correlations for the MR- than for the CT-derived data. For the MR data the threshold algorithm used for binarizing the images substantially affected these correlations. In conclusion, trabecular bone structure parameters assessed in distal radius HRMR and MSCT images are significantly correlated with those determined in corresponding specimen sections (p<0.01). High-resolution MR-derived structure parameters, however, performed better in the prediction of trabecular bone structure. Electronic Publication     

A New Antifungal Antibiotic from Bacillus sp. KM5 Isolated from Rice Rhizospheric Soil

Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Bacterial strain, Bacillus sp. KM5 was recently isolated and characterized by strong antifungal activities...     

Stimulation of oxidative burst in human monocytes by lipoteichoic acids.

Lipoteichoic acid isolated from Streptococcus faecalis or Streptococcus pyogenes caused direct activation of the respiratory burst in human peripheral blood monocytes. This activity appears to be related to the ability of lipoteichoic acid to bind to the monocyte membrane and trigger the polarization of receptors (capping).     

An unusual intranuclear structure (? viral nucleocapsid) in the brain in subacute sclerosing panencephalitis

A brain biopsy was examined from a 7 year old boy with subacute sclerosing panencephalitis. Intranuclear deposits of measles antigens were demonstrated in parenchymal cells by immunofluorescence. Electron microscopy showed viral nucleocapsids in nucleoliform inclusions and unusual rod-like intranuclear structures which resemble structures previously described only in tissue cultures infected with measles virus.     

Efficacies of liposome-encapsulated streptomycin and ciprofloxacin against Mycobacterium avium-M. intracellulare complex infections in human peripheral blood monocyte/macrophages.

Current treatments of disseminated infection caused by the Mycobacterium avium-M. intracellulare complex (MAC) are generally ineffective. Liposome-mediated delivery of antibiotics to MAC-infected tissues in vivo can enhance the efficacy of the drugs (N. Düzgüne?, V. K. Perumal, L. Kesavalu, J. A. Goldstein, R. J. Debs, and P. R. J. Gangadharam, Antimicrob. Agents Chemother. 32:1404-1411, 1988; N. Düzgüne?, D. A. Ashtekar, D. L. Flasher, N. Ghori, R. J. Debs, D. S. Friend, and P. R. J. Gangadharam, J. Infect. Dis. 164:143-151, 1991). We investigated the therapeutic efficacies of liposome-encapsulated streptomycin and ciprofloxacin against growth of the MAC inside human peripheral blood monocyte/macrophages. Treatment was initiated 24 h after infection of macrophages with the MAC and stopped after 20 h, and the cells were incubated for another 7 days. The antimycobacterial activity of streptomycin was enhanced when the drug was delivered to macrophages in liposome-encapsulated form, reducing the CFU about threefold more than the free drug did throughout the concentration range studied (10 to 50 micrograms/ml). With 50 micrograms of encapsulated streptomycin per ml, the CFU were reduced to 11% of the initial level of infection. Liposome-encapsulated ciprofloxacin was at least 50 times more effective against the intracellular bacteria than was the free drug: at a concentration of 0.1 microgram/ml, liposome-encapsulated ciprofloxacin had greater antimycobacterial activity than the free drug at 5 microgram/ml. With liposome-encapsulated ciprofloxacin at 5 micrograms/ml, the CFU were reduced by more than 1,000-fold at the end of the 7-day incubation period, compared with untreated controls. These results suggest that liposome-encapsulated ciprofloxacin or other fluoroquinolones may be effective against MAC infections in vivo.     

Microalbuminuria: A novel biomarker of sepsis

Context:

Diffused endothelial dysfunction in sepsis leads to an increase in systemic capillary permeability, the renal component manifesting as microalbuminuria. The degree of microalbuminuria correlates with the severity of the acute insult, the quantification of which may serve to predict sepsis and mortality in critically ill patients.

Aims:

To evaluate whether the degree of microalbuminuria could differentiate patients with sepsis from those without and predict mortality in critically ill patients.

Settings and Design:

Prospective, non-interventional study in a 20-bed Intensive Care Unit (ICU) of a tertiary care hospital.

Methods and Materials:

After exclusions, between Jan-May 2007, 94 consecutive adult patients were found eligible. Albumin-creatinine ratio (ACR, mg/g) was measured in urine samples collected on ICU admission (ACR1) and at 24 hours (ACR2).

Results:

Patients were classified into two groups: those with sepsis, severe sepsis and septic shock (n = 30) and those without sepsis [patients without systemic inflammatory response syndrome (SIRS) and with SIRS due to noninfectious causes] (n = 64). In the sepsis group, median ACR1 [206.5 (IQR129.7-506.1)] was significantly higher compared to the non sepsis group [76.4 (IQR29-167.1)] (P = 0.0016, Mann Whitney). The receiver operating characteristics (ROC) curve analysis showed that at a cut off value 124 mg/g, ACR1 may be able to discriminate between patients with and without sepsis with a sensitivity of 80%, specificity of 64.1%, positive predictive value (PPV) of 51.1% and negative predictive value (NPV) of 87.3%. The median ACR2 [154 (IQR114.4-395.3)] was significantly higher (P = 0.004) in nonsurvivors (n = 13) as compared to survivors [50.8 (IQR 21.6-144.7)]. The ROC curve analysis revealed that ACR2 at a cut-off of 99.6 mg/g could predict ICU mortality with sensitivity of 85%, specificity of 68% with a NPV of 97% and PPV of 30%.

Conclusion:

Absence of significant microalbuminuria on ICU admission is unlikely to be associated with sepsis. At 24 hours, absence of elevated levels of microalbuminuria is strongly predictive of ICU survival, equivalent to the time-tested APACHE II scores.