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Hereditary spastic paraplegias are characterized by lower limb spasticity resulting from degeneration of long corticospinal axons. SPG11 is one of the most common autosomal recessive hereditary spastic paraplegias, and the SPG11 protein spatacsin forms a complex with the SPG15 protein spastizin and heterotetrameric AP5 adaptor protein complex, which includes the SPG48 protein AP5Z1. Using the integration-free episomal method, we established SPG11 patient-specific induced pluripotent stem cells (iPSCs) from patient fibroblasts. We differentiated SPG11 iPSCs, as well as SPG48 iPSCs previously established, into cortical projection neurons and examined protective effects by targeting mitochondrial dynamics using P110, a peptide that selectively inhibits mitochondrial fission GTPase Drp1. P110 treatment mitigates mitochondrial fragmentation, improves mitochondrial motility, and restores mitochondrial health and ATP levels in SPG11 and SPG48 neurons. Neurofilament aggregations are increased in SPG11 and SPG48 axons, and these are also suppressed by P110. Similarly, P110 mitigates neurofilament disruption in both SPG11 and SPG48 knockdown cortical projection neurons, confirming the contribution of hereditary spastic paraplegia gene deficiency to subsequent neurofilament and mitochondrial defects. Strikingly, neurofilament aggregations in SPG11 and SPG48 deficient neurons double stain with ubiquitin and autophagy related proteins, resembling the pathological hallmark observed in SPG11 autopsy brain sections. To confirm the cause-effect relationship between the SPG11 mutations and disease phenotypes, we knocked-in SPG11 disease mutations to human embryonic stem cells (hESCs) and differentiated these stem cells into cortical projection neurons. Reduced ATP levels and accumulated neurofilament aggregations along axons are observed, and both are mitigated by P110. Furthermore, rescue experiment with expression of wild-type SPG11 in cortical projection neurons derived from both SPG11 patient iPSCs and SPG11 disease mutation knock-in hESCs leads to rescue of mitochondrial dysfunction and neurofilament aggregations in these SPG11 neurons. Finally, in SPG11 and SPG48 long-term cultures, increased release of phosphoNF-H, a biomarker for nerve degeneration, is significantly reduced by inhibiting mitochondrial fission pharmacologically using P110 and genetically using Drp1 shRNA. Taken together, our results demonstrate that impaired mitochondrial dynamics underlie both cytoskeletal disorganization and axonal degeneration in SPG11 and SPG48 neurons, highlighting the importance of targeting these pathologies therapeutically.

Neurons have intense demands for high energy in order to support their functions. Impaired mitochondrial transport along axons has been observed in human neurons, which may contribute to neurodegeneration in various disease states. Although it is challenging to examine mitochondrial dynamics in live human nerves, such paradigms are critical for studying the role of mitochondria in neurodegeneration. Described here is a protocol for analyzing mitochondrial transport and mitochondrial morphology in forebrain neuron axons derived from human induced pluripotent stem cells (iPSCs). The iPSCs are differentiated into telencephalic glutamatergic neurons using well-established methods. Mitochondria of the neurons are stained with MitoTracker CMXRos, and mitochondrial movement within the axons are captured using a live-cell imaging microscope equipped with an incubator for cell culture. Time-lapse images are analyzed using software with "MultiKymograph", "Bioformat importer", and "Macros" plugins. Kymographs of mitochondrial transport are generated, and average mitochondrial velocity in the anterograde and retrograde directions is read from the kymograph. Regarding mitochondrial morphology analysis, mitochondrial length, area, and aspect ratio are obtained using the ImageJ. In summary, this protocol allows characterization of mitochondrial trafficking along axons and analysis of their morphology to facilitate studies of neurodegenerative diseases.

Fungal infections, particularly Candida species, have increased worldwide and caused high morbidity and mortality rates. The toxicity and development of resistance in present antifungal drugs justify the need of new drugs with different mechanism of action. BMVC-12C-P, a carbazole-type compound, has been found to dysfunction mitochondria. BMVC-12C-P displayed the strongest antifungal activities among all of the BMVC derivatives. The minimal inhibitory concentration (MIC) of BMVC-12C-P against Candida species ranged from 1 to 2 μg/ml. Fluconazole-resistant clinical isolates of Candida species were highly susceptible to BMVC-12C-P. The potent fungicidal activity of BMVC-12C-P relates to its impairing mitochondrial function. Furthermore, we found that the hyphae growth and biofilm formation were suppressed in C. albicans survived from BMVC-12C-P treatment. This study demonstrates the potential of BMVC-12C-P as an antifungal agent for treating Candida infections.

Although histopathological dermal elastosis is the current gold standard for the diagnosis of photoageing, noninvasive methods for quantifying the amount of photodamage to skin are clearly preferable. This study is the first to survey five noninvasive methods of assessing photoageing (clinical examination, spectrophotometry, skin surface topography, reflectance confocal microscopy and fluorescence lifetime imaging microscopy) in the same individual. Measurements for each noninvasive method were compared across nine individuals from three participant groups ('younger', 'older' and 'photodamaged') in UV-protected volar and UV-exposed dorsal forearm skin. Overall, participants in the younger group had the lowest measures of photodamage, while those in the photodamaged group had the highest, as indicated by each modality. The five noninvasive strategies surveyed in this study may demonstrate potential as a suitable methodology for the quantification of photoageing. The advantage of such noninvasive methods is that they allow for skin visualisation in vivo and repeated assessments of the same site. The main limitation of this study was its small sample size, which may have precluded many findings of statistical significance.

BACKGROUND:: The aim of this paper is to assess the effect that the isolated coronal plane obliquity/angle of cut made for an opening wedge osteotomy has on the opening wedge gap, and determine whether this effect is likely to have clinical relevance with respect to bony union. The proximal tibial osteotomy has been used as an example. METHODS:: Mathematical/schematic assessment. RESULTS:: The single plane obliquity of the osteotomy cut cannot be used in isolation to predict opening gap distance, unless an osteotomy is performed on a perfectly cylindrical bone whereby the smallest gap is produce by the most horizontal cut. CONCLUSIONS:: Reducing the opening gap distance can be achieved by utilizing the shortest osteotomy through the bone at the desired point of correction. CLINICAL RELEVANCE:: The degree of change in opening wedge gap between various angles of high tibial opening wedge osteotomy is small-and focus should probably be placed on other mechanical and surgical considerations.

Binding of melanocortin peptide agonists to the melanocortin-1 receptor of melanocytes results in eumelanin production, whereas binding of the agouti signalling protein inverse agonist results in pheomelanin synthesis. Recently, a novel melanocortin-1 receptor ligand was reported. A β-defensin gene mutation was found to be responsible for black coat colour in domestic dogs. Notably, the human equivalent, β-defensin 3, was found to bind with high affinity to the melanocortin-1 receptor; however, the action of β-defensin as an agonist or antagonist was unknown. Here, we use in vitro assays to show that β-defensin 3 is able to act as a weak partial agonist for cAMP signalling in human embryonic kidney (HEK) cells expressing human melanocortin-1 receptor. β-defensin 3 is also able to activate MAPK signalling in HEK cells stably expressing either wild type or variant melanocortin-1 receptors. We suggest that β-defensin 3 may be a novel melanocortin-1 receptor agonist involved in regulating melanocyte responses in humans.

An economic motion and texture aware denosing framework is proposed to facilitate parallel hardware design. The denoising framework performs on a block basis and features a spatial and temporal predictor and then a linear denoising filter optimal in the Minimum Mean Square Error (MMSE) sense. We first analyze the texture and motion strength around the neighborhood of a noisy pixel and then produce an effective predictor to correlate with the pixel of interest. Both the predictor and the noisy pixel are input into the linear denoiser to finally remove the noise. This framework only refers the information of the neighborhood of a noisy pixel and explores the best spatial and temporal denoising ratio adaptive to its local characteristics. Experiments show that the proposed framework outperforms the traditional block based denoising method by 1–3 dB of PSNR in denoising quality and also achieves a 1–3 dB gain when using it in HEVC encoder.

AVS2 is an ongoing standardization effort by Audio Video coding Standard Workgroup of China toward high efficiency coding of multimedia compared to the previous standard (AVS1). AVS2-P2 is the video part for high-definition, ultra-high-definition and three dimensional video contents. Raw video content of 10-bit bit depth has superior visual quality compared to traditional 8-bit counterpart. Thanks to the advance of computing power of hardware, support for video content of 10-bit bit depth is becoming very important in current high resolution video processing applications. We present here a new 10-bit design to AVS2-P2 standard based on our 10-bit encoding proposal [1] on the 48 th AVS2 working group meeting.

Refereed/Peer-reviewed

Ocular vasospasm in response to local and/or systemic stimuli may contribute to ischemia of the optic nerve. The Hettinger hand vibration test was applied to patients with and without glaucoma to identify subgroups with a high systemic vasospastic tendency. A total of 580 subjects were tested (113 controls, 86 glaucoma suspects, 270 with primary open-angle glaucoma, 71 with secondary open-angle glaucoma, 30 with normal-tension glaucoma, and 10 with angle-closure glaucoma). The frequency distribution curve of Hettinger scores (HS) was bimodal, suggesting two distinct groups. Within each diagnostic group, a subpopulation with a high HS could be identified. Multivariate analysis demonstrated a significant association between the nonselective topical beta-blocker timolol and higher mean HS (P = 0.04) and a significantly higher proportion of subjects with HS of 1.5 or more (P = 0.01). Although subjects taking systemic beta1-selective blockers had significantly lower mean HS (P = 0.04), the proportion of patients with HS of 1.5 or more was not affected significantly by topical and systemic beta1-selective blocker use. Whereas topical nonselective beta-blockers may have an adverse effect on vasospastic tendency, systemic beta1-selective blockers may be partially protective against this effect.

Although histopathological dermal elastosis is the current gold standard for the diagnosis of photoageing, noninvasive methods for quantifying the amount of photodamage to skin are clearly preferable. This study is the first to survey five noninvasive methods of assessing photoageing (clinical examination, spectrophotometry, skin surface topography, reflectance confocal microscopy and fluorescence lifetime imaging microscopy) in the same individual. Measurements for each noninvasive method were compared across nine individuals from three participant groups ('younger', 'older' and 'photodamaged') in UV-protected volar and UV-exposed dorsal forearm skin. Overall, participants in the younger group had the lowest measures of photodamage, while those in the photodamaged group had the highest, as indicated by each modality. The five noninvasive strategies surveyed in this study may demonstrate potential as a suitable methodology for the quantification of photoageing. The advantage of such noninvasive methods is that they allow for skin visualisation in vivo and repeated assessments of the same site. The main limitation of this study was its small sample size, which may have precluded many findings of statistical significance.

Binding of melanocortin peptide agonists to the melanocortin-1 receptor of melanocytes results in eumelanin production, whereas binding of the agouti signalling protein inverse agonist results in pheomelanin synthesis. Recently, a novel melanocortin-1 receptor ligand was reported. A β-defensin gene mutation was found to be responsible for black coat colour in domestic dogs. Notably, the human equivalent, β-defensin 3, was found to bind with high affinity to the melanocortin-1 receptor; however, the action of β-defensin as an agonist or antagonist was unknown. Here, we use in vitro assays to show that β-defensin 3 is able to act as a weak partial agonist for cAMP signalling in human embryonic kidney (HEK) cells expressing human melanocortin-1 receptor. β-defensin 3 is also able to activate MAPK signalling in HEK cells stably expressing either wild type or variant melanocortin-1 receptors. We suggest that β-defensin 3 may be a novel melanocortin-1 receptor agonist involved in regulating melanocyte responses in humans.

Two short visual field tests were performed on 106 subjects approximately 5 minutes apart with or without a hand vibration stimulus between the field tests. There were 31 eyes in the control group (10 without glaucoma, eight glaucoma suspects, 10 with primary open-angle glaucoma, and three with secondary open-angle glaucoma). There were 75 eyes in the hand vibration group (16 without glaucoma, 20 glaucoma suspects, 25 with primary open-angle glaucoma, eight with secondary open-angle glaucoma, three with normal-tension glaucoma, and three with other forms of glaucoma). Average visual field sensitivities were significantly reduced in the arcuate zones after a hand vibration stimulus (−0.42 dB; SD, 1.26 dB) when compared with sensitivities in the arcuate zones in subjects without the hand vibration stimulus (+0.38 dB; SD, 1.53 dB; P = 0.01). Multivariate analysis demonstrated a significant reduction in this response in the arcuate zone associated with use of betaxolol (P = 0.021) and timolol (P = 0.047). Betaxolol was associated with significantly smaller reductions in visual field sensitivities in the paracentral zone (P = 0.01). Reductions in visual field sensitivities that may be related to ocular vasospasm occurred after a hand vibration stimulus. This response may be able to be modified pharmacologically with topical β-blockers, particularly betaxolol.

There are many simple techniques available for source reduction of wastes from metal plating operations. They may be grouped into eight categories: reactive rinsing, counterflow rinsing, dragout minimization, dragout recovery, process modifications/operational changes, material substitutions, waste exchange opportunities and housekeeping improvements. A technical assistance project and financial incentive programs offered by Environment Canada are also described.