Genome stability can be threatened by both endogenous and exogenous agents. Organisms have evolved numerous mechanisms to repair DNA damage, including homologous recombination (HR) and non-homologous ...end joining (NHEJ). Among the factors associated with DNA repair, the MRE11-RAD50-NBS1 (MRN) complex (MRE11-RAD50-XRS2 in
Saccharomyces cerevisiae
) plays important roles not only in DNA damage recognition and signaling but also in subsequent HR or NHEJ repair. Upon detecting DNA damage, the MRN complex activates signaling molecules, such as the protein kinase ataxia-telangiectasia mutated (ATM), to trigger a broad DNA damage response, including cell cycle arrest. The nuclease activity of the MRN complex is responsible for DNA end resection, which guides DNA repair to HR in the presence of sister chromatids. The MRN complex is also involved in NHEJ, and has a species-specific role in hairpin repair. This review focuses on the structure of the MRN complex and its function in DNA damage repair.
Hypertrophic scars are one of the most important complications in surgery due to their cosmetic and functional impairments. Previous studies in tissue fibrotic disorders have shown promising results ...by inhibiting the biological activity effect of Transforming Growth Factor-beta 1 (TGF-β1). The aim of the current study was to determine the clinical effect of the inhibition of TGF-β1 signaling in human hypertrophic scars implanted in nude mice by topical application of an inhibitor of TGF-β1 (P144®).
A total of 30 human hypertrophic scars were implanted in 60 nude mice. The animals were divided in two groups, group A (placebo) and group B (treatment). Group C (basal) was considered as the preimplanted scar samples and they were not implanted in the nude mice. After the shedding period, topical application of a lipogel containing placebo (group A) or P144 (group B) was daily administered during two weeks. The animals were sacrificed upon completion of the study. Total area, thickness and collagen fibers area were measure and compared across all groups. Immunohistochemistry was also performed in order to quantify collagen type I and type III and elastic fiber expressions present in the dermis.
Successful shedding was achieved in 83,3% of the xenografts. The mean time for shedding was 35±5.4 days. Statistically significant differences were found in the total area, collagen fibers area and thickness between the groups. Increased elastic fibers and decreased collagen I were found in the P144-treated group compared to the basal group.
Topical application of an inhibitor of TGF-β1 may promote scar maturation and clinical improvement of hypertrophic scar morphology features in an "in vivo" model in nude mice after two weeks of treatment.
CaWRKY40 was previously found to be transcriptionally up‐regulated by Ralstonia solanacearum inoculation (RSI) or heat stress (HS), but the underlying mechanism remains unknown. Herein, we report ...that a double‐W box‐element (DWE) in the promoter of CaWRKY40 is critical for these responses. The upstream W box unit WI of this composite element is crucial for preferential binding by CaWRKY40 and responsiveness to RSI or HS. DWE‐driven CaWRKY40 can be transcriptionally and nonspecifically regulated by itself and by CaWRKY58 and CaWRKY27. The DWE was also found in the promoters of CaWRKY40 orthologs, including AtWRKY40, VvWRKY40, GmWRKY40, CplWRKY40, SaWRKY40, SpWRKY40, NtWRKY40, and NaWRKY40. DWEAtWRKY40 was analogous to DWECaWRKY40 by responding to RSI or HS and AtWRKY40 expression. These data suggest that a conserved response of plants to pathogen infection or HS is probably mediated by binding of the DWE by WRKY40.
Our study reports that a conserved response of plants to pathogen infection or heat shock is probably mediated by the binding of the double‐W box to WRKY40.
Anaerobic ammonia oxidation (ANAMMOX), a sustainable biological process, is promising to remove NH4+-N from municipal sewage. In this study, results showed that the anammox granular sludge morphology ...changes with the alternation of dissolved oxygen (DO), mainly attributing to the adhesion of calcium ions (Ca2+) to the surface of sludge particles. Diverse characterization methods revealed that gray adhesions in the form of hydroxyapatite covered the original holes on the anammox granular sludge surface, including scanning Electron Microscopy (SEM), digital camera images, Energy Dispersive Spectrometer (EDS), and X-ray diffraction (XRD). Ex-situ degradation of NH4+-N and NO2−-N yielded diverse outcomes. The protein to polysaccharide ratio (PN/PS) in the total extracellular polymeric substances (EPS) across 4 size groups demonstrated a decrease under O2 exposure. Microbial community analysis indicated norank_f_A4b and Nitrolancea being the most abundant genus under O2 exposure at day 1 and day 100, respectively. These findings offer an effective strategy to prevent size-larger granular sludge from deteriorating through changing DO and Ca2+ in municipal wastewater in ANAMMOX.
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•DO could promote the adhesion of Ca2+ to form Hydroxyapatite, affecting the TNRE.•The larger the sludge size, the more aggregation of Hydroxyapatite on the surface.•Study hypothesized O2− generated from O2 acted as Ca2+ aggregation promoter.•Study revealed norank_f_A4b and Nitrolancea as top genera on day 1 and 100.
Background
Breast cancer will affect one in eight women during their lifetime. The opportunity to restore the removed tissue and cosmetic appearance is provided by reconstructive breast surgery ...following skin‐sparing mastectomy (SSM). Mastectomy skin flap necrosis (MSFN) is a common complication following SSM breast reconstruction. This postoperative complication can be prevented by intraoperative assessment of mastectomy skin flap viability and intervention when tissue perfusion is compromised. Indocyanine green fluorescence angiography is presumed to be a better predictor of MSFN compared to clinical evaluation alone.
Objectives
To assess the effects of indocyanine green fluorescence angiography (ICGA) for preventing mastectomy skin flap necrosis in women undergoing immediate breast reconstruction following skin‐sparing mastectomy.
To summarise the different ICGA protocols available for assessment of mastectomy skin flap perfusion in women undergoing immediate breast reconstructions following skin‐sparing mastectomy.
Search methods
We searched the Cochrane Breast Cancer Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL; Issue 3, 2019), MEDLINE, Embase, the World Health Organization's International Clinical Trials Registry Platform (ICTRP) and Clinicaltrials.gov in April 2019. In addition, we searched reference lists of published studies.
Selection criteria
We included studies that compared the use of ICGA to clinical evaluation to assess mastectomy skin vascularisation and recruited women undergoing immediate autologous or prosthetic reconstructive surgery following SSM for confirmed breast malignancy or high risk of developing breast cancer.
Data collection and analysis
Two review authors independently assessed the risk of bias of the included nonrandomised studies and extracted data on postoperative outcomes, including postoperative MSFN, reoperation, autologous flap necrosis, dehiscence, infection, haematoma and seroma, and patient‐related outcomes. The quality of the evidence was assessed using the GRADE approach and we constructed two 'Summary of finding's tables: one for the comparison of ICGA to clinical evaluation on a per patient basis and one on a per breast basis.
Main results
Nine nonrandomised cohort studies met the inclusion criteria and involved a total of 1589 women with 2199 breast reconstructions. We included seven retrospective and two prospective cohort studies. Six studies reported the number of MSFN on a per breast basis for a total of 1435 breasts and three studies reported the number of MSFN on a per patient basis for a total of 573 women. Five studies reported the number of other complications on a per breast basis for a total of 1370 breasts and four studies reported the number on a per patient basis for a total of 613 patients. Therefore, we decided to pool data separately.
Risk of bias for each included nonrandomised study was assessed using the Newcastle‐Ottawa Scale for cohort studies. There was serious concern with risk of bias due to the nonrandomised study design of all included studies and the low comparability of cohorts in most studies. The quality of the evidence was found to be very low, after downgrading the quality of evidence twice for imprecision based on the small sample sizes and low number of events in the included studies.
Postoperative complications on a per patient basis
We are uncertain about the effect of ICGA on MSFN (RR 0.79, 95% CI 0.40 to 1.56; three studies, 573 participants: very low quality of evidence), infection rates (RR 0.91, 95% CI 0.60 to 1.40; four studies, 613 participants: very low quality of evidence), haematoma rates (RR 0.87, 95% CI 0.30 to 2.53; two studies, 459 participants: very low quality of evidence) and seroma rates (RR 1.68, 95% CI 0.41 to 6.80; two studies, 408 participants: very low quality of evidence) compared to the clinical group. We found evidence that ICGA may reduce reoperation rates (RR 0.50, 95% CI 0.35 to 0.72; four studies, 613 participants: very low quality of evidence). One study considered dehiscence as an outcome. In this single study, dehiscence was observed in 2.2% of participants (4/184) in the ICGA group compared to 0.5% of participants (1/184) in the clinical group (P = 0.372). The RR was 4.00 (95% CI 0.45 to 35.45; one study; 368 participants; very low quality of evidence).
Postoperative complications on a per breast basis
We found evidence that ICGA may reduce MSFN (RR 0.62, 95% CI 0.48 to 0.82; six studies, 1435 breasts: very low quality of evidence), may reduce reoperation rates (RR 0.65, 95% CI 0.47 to 0.92; five studies, 1370 breasts: very low quality of evidence) and may reduce infection rates (RR 0.65, 95% CI 0.44 to 0.97; five studies, 1370 breasts: very low quality of evidence) compared to the clinical group. We are uncertain about the effect of ICGA on haematoma rates (RR 1.53, CI 95% 0.47 to 4.95; four studies, 1042 breasts: very low quality of evidence) and seroma rates (RR 0.71, 95% CI 0.37 to 1.35; two studies, 528 breasts: very low quality of evidence).
None of the studies reported patient‐related outcomes.
ICGA protocols: eight studies used the SPY System and one study used the Photodynamic Eye imaging system (PDE) to assess MSFN. ICGA protocols in the included studies were not extensively described in most studies.
Authors' conclusions
Although mastectomy skin flap perfusion is performed more frequently using ICGA as a helpful tool, there is a lack of high‐quality evidence in the context of randomised controlled trials. The quality of evidence in this review is very low, since only nonrandomised cohort studies have been included. With the results from this review, no conclusions can be drawn about what method of assessment is best to use during breast reconstructive surgery. High‐quality randomised controlled studies that compare the use of ICGA to assess MSFN compared to clinical evaluation are needed.
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In this study, Electro-Fenton (E-Fenton) reactions at pH 3.0 were initiated by cathodic generation of H2O2, with subsequent production of OH following the addition of Fe(II) or ...Fe(III) ions into the system. The variation in concentrations of H2O2, Fe(II), total Fe and OH following addition of Fe ions into the E-Fenton system was investigated over a range of conditions. A kinetic model incorporating the key processes operating in the E-Fenton system was developed with particular attention given to (i) cathodic generation of H2O2 and anodic formation of OH, (ii) production of OH via homogeneous Fenton reactions, and (ii) surface reactions including electro-sorption of Fe ions and cathodic reduction of Fe(III) to Fe(II) species resulting in the enhancement of production of OH via surface-located Fenton reactions.
This study presents an overview of the current status of hydrogen production in relation to the global requirement for energy and resources. Subsequently, it symmetrically outlines the advantages and ...disadvantages of various production routes including fossil fuel/biomass conversion, water electrolysis, microbial fermentation, and photocatalysis (PC), in terms of their technologies, economy, energy consumption, and costs. Considering the characteristics of hydrogen energy and the current infrastructure issues, it highlights that onsite production is indispensable and convenient for some special occasions. Finally, it briefly summarizes the current industrialization situation and presents future development and research directions, such as theoretical research strengthening, renewable raw material development, process coupling, and sustainable energy use.
An electrochemical aptasensor was developed by utilizing a DNA walker driven by catalytic hairpin assembly (CHA) with kanamycin as the model analyte. Kanamycin bound to the aptamer, causes the ...release of DNA walker, triggers the CHA reaction, leads to the cyclic movement of the walker’s long arm, and results in cascade amplification of the signal. The guanine-rich sequences of the double-stranded products produced by CHA were folded to form G-quadruplex structures, with electrochemical active molecules Hemin embedded, forms G-quadruplex/Hemin complexes in situ on the electrode surface, thereby achieving sensitive, efficient, and label-free detection of kanamycin with a limit of detection (LOD) of 0.27 pM (S/N = 3). Meaningfully, the aptasensor demonstrated high sensitivity and reliability in the detection of kanamycin in milk and livestock wastewater samples, suggesting that it has great potential for application in detecting antibiotics in food products and water samples from the environment.
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