Alterations in Protein Synthesis in the Cyanobacterium Synechococcus sp. Strain PCC-6301 in Response to Calendula micrantha Extract with Molluscicidal Activity

The response to the extract of the Egyptian wild herb Calendula micrantha, with molluscicidal activity,was examined in the unicellular cyanobacterium Synechococcus sp. strain PCC 6301. Growth and chlorophyll a of the cells were only slightly affected by low concentrations but drastically reduced by high concentrations. The rate of protein synthesis progressively decreased by increasing extract concentration. The cells preferentially induced the synthesis of a limited number of polypeptides in response to the treatment. Among the induced polypeptides were those with apparent molecular weights of 161K (161,000), 96.7K, 93.4K, 85K, 69.9K, 59K, 49K, 45K, 35K, 32.4K, 28K, 24K, 21.7K, 18K, and 16K based on their mobilities in gel electrophoresis. These initial studies suggest that the plant extract exerted certain stress which stimulated alteration in the pattern of protein synthesis in Synechococcus sp. Some of the induced polypeptides are similar to that known to occur in other stresses, especially heat-shock stress.     

Negative socio-emotional resonance in schizophrenia: a functional magnetic resonance imaging hypothesis

The aim of the present study is to use neuroscience theories about brain function (mirror-neurons MN) to draw inferences about the mechanisms supporting emotional resonance in two different groups of schizophrenia patients (with flat affect FA+ n = 13 and without flat affect FA- n = 11). We hypothesize that FA+ will not activate key brain areas involved in emotional processing. Conversely, FA- will have a functional mirror system for emotional resonance confirmed by activation of the prefrontal cortex and behavioral results. To test this hypothesis, we compared the two groups using blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) displaying a passive visual task (44 negative IAPS pictures and 44 neutral pictures). A random-effects analysis, for schizophrenia patients FA-, revealed significant loci of activation in the left mesial prefrontal (MPFC), right orbitofrontal (OFC) and left anterior cingulate cortices (ACC). Correlational analyses carried out between self-report ratings of negative feelings and BOLD signal changes revealed the existence of positive correlation in the LACC, LMPFC and ROFC. Conversely, FA+ did not show significant activation in the prefrontal cortex. We propose that negative emotional resonance induced by passively viewing negative pictures may be a form of "mirroring" that grounds negative feelings via an experiential mechanism. Hence, it could be argued that FA- were able to 'feel' emotions through this resonance behavior. Conversely, we suggest that the dysfunction seen in the FA+ group is a failure or distortion in the development of the MN system. This could be due to genetic or other endogenous causes, which affected prefrontal cortex MN involved in emotional resonance.     

Dysferlin mutations in LGMD2B, Miyoshi myopathy, and atypical dysferlinopathies

DYSF encoding dysferlin is mutated in Miyoshi myopathy and Limb-Girdle Muscular Dystrophy type 2B, the two main phenotypes recognized in dysferlinopathies. Dysferlin deficiency in muscle is the most relevant feature for the diagnosis of dysferlinopathy and prompts the search for mutations in DYSF. DYSF, located on chromosome 2p13, contains 55 coding exons and spans 150 kb of genomic DNA. We performed a genomic analysis of the DYSF coding sequence in 34 unrelated patients from various ethnic origins. All patients showed an absence or drastic decrease of dysferlin expression in muscle. A primary screening of DYSF using SSCP or dHPLC of PCR products of each of 55 exons of the gene was followed by sequencing whenever a sequence variation was detected. All together, 54 sequence variations were identified in DYSF, 50 of which predicting either a truncated protein or one amino-acid substitution and most of them (34 out of 54) being novel. In 23 patients, we identified two pathogenic mutations, while only one was identified in 11 patients. These mutations were widely spread in the coding sequence of the gene without any mutational "hotspot."     

How to improve donor skin availability: Pragmatic procedures to minimize the discard rate of cryopreserved allografts in skin banking

BackgroundMicrobial contamination of human skin allografts is a frequent cause of allograft discard. Our purpose was to evaluate the discard rate of skin bank contaminated allografts and specific procedures used to reduce allograft contamination without affecting safety.MethodsWe conducted at the Lille Tissue Bank a retrospective study of all deceased donors (n = 104) harvested from January 2018 to December 2018. Skin procurement was split into 3 zones: the back of the body and the two legs that were processed separately. It represented 433 cryopreserved skin allograft pouches of approximatively 500 cm² each. Donors were almost equally split between brain-dead (53%, 55/104) and cadaveric (47%, 49/104) donors.ResultsOut of all donors, 42 (40.5%) had at least one sampling zone with a positive microbiological test resulting in 106 (24%) contaminated skin pouches. The contamination rate did not vary according to the harvested zone or type of donor. Traumatic deaths showed significantly less contamination rates than other death types (p < 0.05). Contamination rate decreased with time spent in the antibiotic solution. The risk of having contaminated allografts was five-fold higher when the skin spent less than 96 h in the antibiotic cocktail (p < 0.05). According to our validation protocol, most donors (32/42, 76%) had skin allografts contaminated with bacteria (mainly Staphylococcus spp) compatible with clinical use. No recipient infection was recorded as a result of skin graft contaminated with saprophytic or non-pathogenic germs. By harvesting 3 separate zones per donor, the total surface area for clinical use increased by 53% for contaminated donors. Overall, the proportion of contamination-related discarded allografts was 3.2% (14/433 of pouches).ConclusionFew simple pragmatic measures (including skin incubation in the antibiotic bath for at least 96 h at 4 °C, splitting the skin harvesting areas to minimize the risk of cross-infection and clinical use of allografts contaminated with saprophytic and non-pathogenic germs) can reduce the discard rate of contaminated allografts without affecting clinical safety.     

The value of serologic markers in indeterminate colitis: a prospective follow-up study

BACKGROUND & AIMS: In the absence of pathognomonic markers for Crohn's disease (CD) and ulcerative colitis (UC), the diagnosis of inflammatory bowel disease depends on a compendium of clinical, radiographic, endoscopic, and histologic criteria that bears imperfect specificity to the individual disorders. In 10% of cases of colitis, no differentiation can be made between CD and UC; these patients are diagnosed with indeterminate colitis (IC). We evaluated the value of anti-Saccharomyces cerevisiae antibodies (ASCA) and perinuclear antineutrophil cytoplasmic antibodies (pANCA) to increase diagnostic accuracy in categorizing IC. METHODS: Since 1996, 97 patients with IC from 3 centers (Leuven, Lille, and Vienna) were enrolled, analyzed for pANCA and ASCA, and followed up prospectively. RESULTS: A definitive diagnosis has been reached for 31 of 97 patients (32%). In these patients, ASCA+/pANCA- correlated with CD in 8 of 10 patients, whereas ASCA-/pANCA+ correlated with UC in 7 of 11 patients. The remaining 4 cases became CD, clinically behaving as UC-like CD. Almost half of the patients (47 of 97 [48.5%]) were negative for ASCA and pANCA, and 40 remain diagnosed with IC to date. Only 7 seronegative cases (14.9%) became CD or UC compared with 48% (24 of 50) of seropositive patients (P < 0.001). CONCLUSIONS: Results so far show that ASCA+/pANCA- predicts CD in 80% of patients with IC and ASCA-/pANCA+ predicts UC in 63.6%. Interestingly, 48.5% of patients do not show antibodies against ASCA or pANCA. Most of these patients remain diagnosed with IC during their further clinical course, perhaps reflecting a distinct clinicoserological entity.