The diagnostic use of the second oscillatory potential in clinical electroretinography

Of all the electroretinogram (ERG) components (a-wave, b-wave, and oscillatory potentials) only one oscillatory potential, OP₂, was found to be significantly correlated with the absolute intensity of the flash stimulus (i.e., the intensity of the stimulus irrespective of the state of retinal adaptation). Our finding was further confirmed in single cell recordings of lateral geniculate unit activity in rabbits in which peak time of OP₂ was found to correlate better with the geniculate activity. For these reasons we have identified OP₂ as the intensity coding oscillatory potential of the ERG. In order to investigate if this new feature could have some clinical significance, we examined photopic ERGs recorded from patients affected with various retinopathies. In most instances the peak time of OP₂ paralleled that of the b-wave, that is, in the ERG with delayed b-wave the peak time of OP₂ was also delayed, while in ERGs with normal b-wave peak time the peak time of OP₂ was also normal. However, in some conditions (especially in cone-rod diseases) a delayed OP₂ was found in ERGs with normal b-wave peak times.     

Isolation of a fastidious Bergeyella species associated with cellulitis after a cat bite and a phylogenetic comparison with Bergeyella zoohelcum strains

Bergeyella zoohelcum is an uncommon zoonotic pathogen typically associated with cat or dog bites. Previously, only five cases of B. zoohelcum infection have been reported. We report the isolation and characterization of a fastidious Bergeyella species from acute cellulitis in the upper extremity of a 60-year-old woman. The organism was too fastidious for identification and susceptibility testing with traditional culture methods. The isolate was characterized further by PCR amplification and sequencing of the 16S rRNA gene with broad-range eubacterial primers. Phylogenetic analysis of the 16S ribosomal DNA sequence indicated that this isolate was a member of the species B. zoohelcum (previously Weeksella zoohelcum), a gram-negative bacillus that is rarely associated with infections in humans. Despite sharing a close genetic relationship with other B. zoohelcum strains, this isolate was extremely fastidious in nature, raising the possibility that similar strains from cat or dog bite wound infections have been underreported.     

Prospective evaluation of the new chromogenic medium Candida ID, in comparison with Candiselect, for isolation of molds and isolation and presumptive identification of yeast species

We conducted a prospective evaluation of Candida ID chromogenic medium (bioMérieux, Marcy l'Etoile, France) with 786 clinical specimens in comparison with Candiselect medium (Bio-Rad, Marnes la Coquette, France). Candida ID chromogenic medium identified 97.7% of Candida albicans strains; enabled presumptive identification of C. tropicalis, C. lusitaniae, C. guillermondii, and C. kefyr and better detection of yeast combinations (11.4% more often); and was more sensitive for the isolation of filamentous fungi (17.7% more often). However, Candida ID chromogenic medium appeared to be less selective vis-à-vis bacteria, with bacterial colonies sometimes pigmented blue.     

Hernia repair and time off work in Oxford

The variation in time off work was investigated in 261 men aged between 18 and 65 years whose inguinal herniae were repaired in Oxford hospitals in 1971/72 and 1974/75. The average time off was 51 calendar days compared with 70 days nationally. Complications, a heavy job, low sick pay, and family worries were found to be the main factors associated with increased time off, although they accounted for only 42 per cent of the variance. Men stopping smoking at the surgeon's request had less time off, and so had men who had been given an estimate before their operation of their likely duration of absence, especially when the estimate was given by the surgeon.     

Effect of aging on neuroglobin expression in rodent brain

Neuroglobin (Ngb), a recently discovered O2-binding heme protein related to hemoglobin and myoglobin, protects neurons from hypoxic-ischemic injury in vitro and in vivo. In immunostained mouse brain sections, we found widespread expression of Ngb protein in neurons, but not astrocytes, of several brain regions that are prominently involved in age-related neurodegenerative disorders. Western blots from young adult (3 month), middle-aged (12 month), and aged (24 month) rats showed an age-related decline in Ngb expression in cerebral neocortex, hippocampus, caudate-putamen, and cerebellum. Loss of this neuroprotective protein may have a role in increasing susceptibility to age-related neurological disorders.     

Triglycidylamine crosslinking of porcine aortic valve cusps or bovine pericardium results in improved biocompatibility, biomechanics, and calcification resistance: chemical and biological mechanisms

We investigated a novel polyepoxide crosslinker that was hypothesized to confer both material stabilization and calcification resistance when used to prepare bioprosthetic heart valves. Triglycidylamine (TGA) was synthesized via reacting epichlorhydrin and NH(3). TGA was used to crosslink porcine aortic cusps, bovine pericardium, and type I collagen. Control materials were crosslinked with glutaraldehyde (Glut). TGA-pretreated materials had shrink temperatures comparable to Glut fixation. However, TGA crosslinking conferred significantly greater collagenase resistance than Glut pretreatment, and significantly improved biomechanical compliance. Sheep aortic valve interstitial cells grown on TGA-pretreated collagen did not calcify, whereas sheep aortic valve interstitial cells grown on control substrates calcified extensively. Rat subdermal implants (porcine aortic cusps/bovine pericardium) pretreated with TGA demonstrated significantly less calcification than Glut pretreated implants. Investigations of extracellular matrix proteins associated with calcification, matrix metalloproteinases (MMPs) 2 and 9, tenascin-C, and osteopontin, revealed that MMP-9 and tenascin-C demonstrated reduced expression both in vitro and in vivo with TGA crosslinking compared to controls, whereas osteopontin and MMP-2 expression were not affected. TGA pretreatment of heterograft biomaterials results in improved stability compared to Glut, confers biomechanical properties superior to Glut crosslinking, and demonstrates significant calcification resistance.     

Quantifying the Ripple Effects of Civil War: How Armed Conflict Is Associated with More Severe Violence in the Home

Both the fields of public health and that of human rights seek to improve human well-being, including through reducing and preventing all forms of violence, to help individuals attain the highest quality of life. In both fields, mathematical methods can help “visibilize” the hidden architecture of violence, bringing new methods to bear to understand the scope and nuance of how violence affects populations. An increasing number of studies have examined how residing in a conflict-affected place may impact one of the most pervasive forms of violence—intimate partner violence (IPV)—during and after conflict. This paper contributes to this effort by examining whether severe forms of IPV are associated with previous experience of political violence in one conflict-affected country: Liberia. Our findings indicate that living in a district with conflict fatalities increased the risk of IPV among women by roughly 60%. Additionally, living in a district with conflict fatalities increased the risk of a past-year injury from IPV by 50%. This analysis brings to light links between two of the most pervasive forms of violence—political violence and violence against women. The findings suggest that women residing in a district that is more highly affected by conflict, not only people experiencing direct trauma during conflict, may be at risk of increased violence long after peace is declared. These findings point to the need for targeted programs that address IPV postconflict.