Outbreak of vampire bat biting in a Venezuelan village

An outbreak of 154 cases of vampire bat biting in a four-month period in the gold mine of Payapal, a Venezuelan village, is reported. All patients were bitten during the night and the most bites were on their toes. No complication attributed to the bite was reported. Diagnoses of rabies virus made by means of immunofluorescence were negative. A possible reason for this outbreak may been the development of mining areas, with the inhabitants providing an alternative food source for the bats.     

Postsurgical wound progression monitored by temporal changes in the expression of matrix metalloproteinase-9

It is important to monitor the early stages of postoperative wound repair in order to identify those problems associated with impaired healing. Many of the crucial cellular responses of early wound healing, such as inflammatory infiltration, angiogenesis and re-epithelialization, are made possible through the action of matrix metalloproteinases (MMPs). Expression of MMP-2 and MMP-9 is elevated in acute wounds, and still greater levels are found in chronic wounds, indicating that uncontrolled proteolysis is a characteristic of retarded healing. Therefore, comparative measurements of MMPs may be used to monitor the progression of early wound healing. To investigate this, wound fluids and sera were collected from mastectomy and colectomy patients throughout early stages of repair, and the temporal expression profile established. Wounds which were healing were expressed maximal levels of MMP-9 at 24 h, followed by a significant decline by 48 h. Persistent elevation of MMP-9 expression was associated with infected and chronic wounds, and was identified in postoperative wounds by the absence of the significant decline between 24 and 48 h. Measurement of MMP-9 in postoperative wound fluids, therefore, provides an early indicator of impaired healing, which may be evaluated non-invasively within 48 h of closure.     

Calibrating screens for continuous colour displays

This paper focuses on two issues that are important to those who use colour monitors for research in vision. One is concerned with the measurement and calibration of colour screens. To this end the luminance and chromaticity readings of a tri-filter colorimeter and a spectroradiometer are compared (both commonly used to calibrate screens). The second is concerned with screen interactions, whereby colours can be distorted from their expected or calculated values by the colours displayed in neighbouring areas. This issue is crucial for those who use measurements of the light emitted from the red, green and blue phosphors of a monitor in isolation to specify other colours on screen, particularly in the research areas of colour contrast and colour constancy, since the specified colours may not actually be displayed. Finally, an alternative calibration method is described that uses an iterative measurement procedure to obtain screen specifications that are accurate regardless of the display complexity, so that researchers can be confident that the required colours are actually displayed on the screen.     

Porphyromonas (Bacteroides) endodontalis: its role in endodontal infections

Porphyromonas endodontalis (formerly Bacteroides endodontalis) is a black-pigmented anaerobic Gram-negative rod which is associated with endodontal infections. It has been isolated from infected dental root canals and submucous abscesses of endodontal origin. The presence of P. endodontalis in infected dental root canals has been correlated with symptoms of an acute infection. It is occasionally found on oral mucous membranes and periodontal pockets. P. endodontalis has shown relatively low virulence in experimental monoinfections. In anaerobic mixed infections it can play an essential role. Differences in virulence between strains have been related to capsular material. On the basis of different types of capsules, three serotypes have been described. P. endodontalis is sensitive to a wide range of antibiotics, including the penicillins, the tetracyclines, and metronidazole.     

FOS is induced by singing in distinct neuronal populations in a motor network

The acute and subacute effects of intracerebroventricularly (ICV) administered nerve growth factor (NGF) or brain-derived neurotrophic factor (BDNF) on locomotor activity were evaluated in awake adult rats. Immediately after ICV injection through an implanted cannula, locomotor activity was measured by a computerized system using infrared photocells, which allowed us to record locomotion, motility, and rearing simultaneously. A single dose of 5 microg mouse beta-NGF produced significant increases in horizontal ambulatory components of locomotor activity (locomotion and motility), but not vertical movement (rearing) 30-45 min after ICV administration. These increases lasted for at least 3-4 h. Systemic injection of 2.0 mg/kg mecamylamine, a central nicotinic receptor antagonist, inhibited the hyperactivity induced by NGF. Systemic injection of 0.5 mg/kg scopolamine, a muscarinic receptor antagonist, did not interfere with the NGF effects. Thus, while scopolamine induced marked increases in all three measures of behavior in both NGF and cytochrome-c-treated animals, locomotion and motility remained significantly higher in the NGF group. Immunohistochemistry demonstrated that NGF diffused readily from the ventricular space into brain parenchyma on the injected side and could be visualized 1 h after ICV injection. These results suggest that ICV administration of NGF increases locomotor activity by inducing acetylcholine release, and that nicotinic receptors are involved in the hyperactivity induced by NGF. ICV administration of 5 microg recombinant human BDNF had no significant effect on locomotor activity during the 0- to 4-h period after ICV injection. However, it produced significant decreases in locomotion, motility, and rearing 24-26 h later. Hence ICV administration of BDNF has entirely different effects on animal behavior from those evoked by NGF. While NGF elicits increases in ambulatory behavior within hours, BDNF causes delayed decreases in ambulatory behavior.     

CBF beta-SMMHC, expressed in M4Eo AML, reduced CBF DNA-binding and inhibited the G1 to S cell cycle transition at the restriction point in myeloid and lymphoid cells

CBF beta-SMMHC is expressed from the inv(16) chromosome in M4Eo AML. Mice lacking CBF subunits or expressing the CBF beta-SMMHC or AML1-ETO oncoproteins failed to develop definitive hematopoiesis. To investigate these effects on hematopoiesis, we expressed CBF beta-SMMHC from the metallothionein promoter, in both 32D cl3 myeloid cells and Ba/F3 B-lymphoid cells. Addition of zinc increased CBF beta-SMMHC levels more than tenfold, with higher levels evident in Ba/F3 lines. Levels obtained in 32D cl3 cells were similar to those of endogenous CBF beta. Indirect immunofluorescence revealed zinc-inducible speckled, nuclear staining in Ba/F3 cells and diffuse nuclear staining in 32D cl3 cells. CBF beta-SMMHC reduced endogenous CBF DNA-binding fivefold in both cell types, increased cell generation time 1.9-fold, on average, in 32D cl3 cells and 1.5-fold in Ba/ F3 cells and decreased tritiated thymidine incorporation into DNA correspondingly. CBF beta-SMMHC increased the proportion of cells in G1 1.7-fold, on average, in 32D cl3 and Ba/F3 cells, and decreased the proportion of cells in S phase by a similar degree. CBF beta-SMMHC induced a marked increase in hypophosphorylated Rb, but did not alter IL-3 Receptor alpha or beta subunit levels. Neither apoptosis nor 32D differentiation was induced by zinc in IL-3 in these lines. Induction of CBF beta-SMMHC in 32D cl3 cells did not inhibit their differentiation to neutrophils or their expression of myeloperoxidase mRNA in G-CSF, and did not produce an eosinophilic phenotype. Additional, proliferative genetic changes in M4eo AMLs might potentiate inhibition of differentiation by CBF beta-SMMHC by allowing its increased expression.