Neurosensory Recovery Following Mental Nerve Skeletonization in Intraoral Open Reduction and Internal Fixation of Mandible Fractures.

PURPOSE: The purpose of this study was to evaluate neurosensory recovery after mental nerve skeletonization in open reduction and internal fixation (ORIF) of mandible fractures. METHODS: This was a prospective nonrandomized observation study of adult subjects treated at a Level I trauma center between April 1, 2016 and December 31, 2019, with mental nerve skeletonization for ORIF of mandible fractures. Age, sex, and mandibular injury severity score (MISS), and functional sensory recovery (FSR) and subjective neurosensory recovery of skeletonized mental nerve were recorded at preoperative and regularly scheduled follow-up appointments. Uninomial and multinomial logistic regressions were conducted with a significance level of < 0.05. RESULTS: Twenty-six subjects (all male) completed all the postoperative protocol requirements and were included in this study. All subjects had a loss of FSR (S0) and subjective neurosensation immediately after surgery. Half of the subjects achieved FSR (S3) and subjective neurosensory recovery (VAS < 4) an average of 42 days after surgery. All subjects improved FSR (S4) by 57 days and subjective neurosensory recovery by 90 days after surgery. These were independent of MISS but had decreased recovery time with increased age. No incidences of mental nerve neuropathic pain during the trial period were found. CONCLUSIONS: FSR and subjective neurosensory recovery from mental nerve skeletonization in intraoral ORIF of mandible fractures was achieved in all subjects by the end of this study. Neurosensory recovery was independent of MISS but decreased with increased age. Initial inverse correlations between objective and subjective neurosensory assessments were insignificant at study completion. No incidences of neuropathic pain were identified during the time of this study. Mental nerve skeletonization in ORIF of mandible fracture may be performed with an anticipated return of functional and subjective neurosensory recovery within 3 months of surgery.

Seawater transmission and infection dynamics of pilchard orthomyxovirus (POMV) in Atlantic salmon (Salmo salar).

The Tasmanian salmon industry had remained relatively free of major viral diseases until the emergence of pilchard orthomyxovirus (POMV). Originally isolated from wild pilchards, POMV is of concern to the industry as it can cause high mortality in farmed salmon (Salmo salar). Field observations suggest the virus can spread from pen to pen and between farms, but evidence of passive transmission in sea water was unclear. Our aim was to establish whether direct contact between infected and naïve fish was required for transmission, and to examine viral infection dynamics. Atlantic salmon post-smolts were challenged with POMV by either direct exposure via cohabitation or indirect exposure via virus-contaminated sea water. POMV was transmissible in sea water and direct contact between fish was not required for infection. Head kidney and heart presented the highest viral loads in early stages of infection. POMV survivors presented low viral loads in most tissues, but these remained relatively high in gills. A consistent feature was the infiltration of viral-infected melanomacrophages in different tissues, suggesting an important role of these in the immune response to POMV. Understanding POMV transmission and host-pathogen interactions is key for the development of improved surveillance tools, transmission models and ultimately for disease prevention.

Pilchard orthomyxovirus (POMV). II. Causative agent of salmon orthomyxoviral necrosis, a new disease of farmed Atlantic salmon Salmo salar.

Since 2012, an orthomyxo-like virus has been consistently linked to epizootics in marine farmed Atlantic salmon in Tasmania, Australia. Here we describe the properties of the virus, designated the pilchard orthomyxovirus (POMV), in cell culture and present data verifying its direct role in a disease of Atlantic salmon. In infected cells, viral RNA was detectable in both the nucleus and cytoplasm, consistent with the replication cycle of an orthomyxovirus. Viral replication in vitro was temperature-dependent (within a range of 10-20°C), and yields of virus were typically in excess of 107 TCID50 ml-1. In controlled infection trials, cell culture-derived POMV produced significant morbidity in Atlantic salmon fry, pre-smolt and post-smolt. In all cases, the development of disease was rapid, with moribund fish detected within 5 d of direct exposure to POMV, and maximum cumulative morbidity occurring within 4 wk. The experimentally infected fish developed a characteristic suite of gross and microscopic pathological changes, which were consistent with those observed in Atlantic salmon overtly affected by POMV-associated disease on sea farms. These included necrotic lesions across multiple organs that were directly associated with the presence of the virus. Together, our observations indicate that POMV is an endemic virus likely transmitted from wild fish to farmed Atlantic salmon in Tasmania. The virus is pathogenic to Atlantic salmon in freshwater and marine environments and causes a disease that we have named salmon orthomyxoviral necrosis.

Investigation of the microbial metabolism of carbon dioxide and hydrogen in the kangaroo foregut by stable isotope probing.

Kangaroos ferment forage material in an enlarged forestomach analogous to the rumen, but in contrast to ruminants, they produce little or no methane. The objective of this study was to identify the dominant organisms and pathways involved in hydrogenotrophy in the kangaroo forestomach, with the broader aim of understanding how these processes are able to predominate over methanogenesis. Stable isotope analysis of fermentation end products and RNA stable isotope probing (RNA-SIP) were used to investigate the organisms and biochemical pathways involved in the metabolism of hydrogen and carbon dioxide in the kangaroo forestomach. Our results clearly demonstrate that the activity of bacterial reductive acetogens is a key factor in the reduced methane output of kangaroos. In in vitro fermentations, the microbial community of the kangaroo foregut produced very little methane, but produced a significantly greater proportion of acetate derived from carbon dioxide than the microbial community of the bovine rumen. A bacterial operational taxonomic unit closely related to the known reductive acetogen Blautia coccoides was found to be associated with carbon dioxide and hydrogen metabolism in the kangaroo foregut. Other bacterial taxa including members of the genera Prevotella, Oscillibacter and Streptococcus that have not previously been reported as containing hydrogenotrophic organisms were also significantly associated with metabolism of hydrogen and carbon dioxide in the kangaroo forestomach.

The role of coral-associated bacterial communities in Australian Subtropical White Syndrome of Turbinaria mesenterina.

Australian Subtropical White Syndrome (ASWS) is an infectious, temperature dependent disease of the subtropical coral Turbinaria mesenterina involving a hitherto unknown transmissible causative agent. This report describes significant changes in the coral associated bacterial community as the disease progresses from the apparently healthy tissue of ASWS affected coral colonies, to areas of the colony affected by ASWS lesions, to the dead coral skeleton exposed by ASWS. In an effort to better understand the potential roles of bacteria in the formation of disease lesions, the effect of antibacterials on the rate of lesion progression was tested, and both culture based and culture independent techniques were used to investigate the bacterial communities associated with colonies of T. mesenterina. Culture-independent analysis was performed using the Oligonucleotide Fingerprinting of Ribosomal Genes (OFRG) technique, which allowed a library of 8094 cloned bacterial 16S ribosomal genes to be analysed. Interestingly, the bacterial communities associated with both healthy and disease affected corals were very diverse and ASWS associated communities were not characterized by a single dominant organism. Treatment with antibacterials had a significant effect on the rate of progress of disease lesions (p = 0.006), suggesting that bacteria may play direct roles as the causative agents of ASWS. A number of potential aetiological agents of ASWS were identified in both the culture-based and culture-independent studies. In the culture-independent study an Alphaproteobacterium closely related to Roseovarius crassostreae, the apparent aetiological agent of juvenile oyster disease, was found to be significantly associated with disease lesions. In the culture-based study Vibrio harveyi was consistently associated with ASWS affected coral colonies and was not isolated from any healthy colonies. The differing results of the culture based and culture-independent studies highlight the importance of using both approaches in the investigation of microbial communities.