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Background: Arsenical keratosis is a precancerous dermatosis which could be induced by long‐term exposure to arsenic poisoning. Arsenic is often added to traditional Chinese medicine in a non‐compliant manner to increase the effectiveness of psoriasis treatment, which is often the main cause of arsenic poisoning in Chinese patients with psoriasis. Objectives: We performed a systemic review of arsenic keratosis during the past 32 years to better understand the sources, treatment, and prognosis of arsenic keratosis in China. Methods: We searched Medline/PubMed, Embase, CNKI, and Wanfang databases for research studies published between 1992 and 2024. A total of 64 papers with 78 individual Chinese of arsenical keratosis were included in this analysis. Results: Of the patients included in the analysis, 92.21% of arsenic poisoning was due to iatrogenic factors: Chinese traditional medicine. Seventy‐six patients (98.70%) had skin manifestation of hyperkeratotic papules and plaques, 68 patients (88.31%) had hyperpigmentation, 43 cases (55.84%) had hypopigmentation, and only 4 had a clear indication of Mees' lines in nails. A total of 52.63% of patients presented with tumors, including squamous cell carcinoma, Bowen's disease, and basal cell carcinoma. For patients with tumors, 20 opted for surgery, 6 for radiotherapy, and 3 for PDT. All patients with only cutaneous tumors are currently well‐controlled. Death occurred in one patient with metastatic squamous cell carcinoma. Keratinizing papules improved significantly in 70.59% of patients treated with Acitretin Capsules. Conclusions: In this study, arsenic sources in Chinese patients were mainly from traditional Chinese medicine, and there were no reports of exposure to water sources or occupational sources in the past 32 years. Most of the patients showed keratinizing papules and pigmentation, and more than 1/2 of the patients showed skin tumors, mainly squamous cell carcinoma. The treatments of tumors are mainly surgical treatment, PDT and radiotherapy can also be selected. The improvement in keratinizing rash was greater than 70% with acitretin capsules. Patients with this disease should be regularly followed up for early detection and timely treatment of potential malignant tumors. [ABSTRACT FROM AUTHOR]

Longitudinal corrugated tubes (LCTs) exhibit stable platform force under axial compression but have low specific energy absorption. Conversely, circumferential corrugated tubes (CCTs) offer higher specific energy absorption but with unstable platform force. To overcome these limitations, this paper introduces a novel bi-directional corrugated tube (BCT) that amalgamates the strengths of both the CCT and LCT while mitigating their weaknesses. The BCT is formed by rolling a bi-directional corrugated structure into a circular tubular form. Numerical simulations of the BCT closely align with experimental results. The study further examines the influence of discrete parameters on the BCT's performance through simulations and identifies the tube's optimal design using the integral entropy TOPSIS method. A full factorial experimental approach is then employed to investigate the impact of radial amplitude, axial amplitude, and neutral surface diameter on the crushing behavior of the BCT, comparing it with the CCT and LCT. The results reveal that increasing A i enhances the axial resistance of the structure, while increasing A j reduces the buckling effect, resulting in a higher specific energy absorption and lower ultimate load capacity for the BCT compared to the CCT and LCT. A simultaneous multi-objective optimization of the CCT, LCT, and BCT confirms that the BCT offers superior specific energy absorption and ultimate load capacity. The optimal configuration parameters for the BCT have been determined, providing significant insights for practical applications in crashworthiness engineering. [ABSTRACT FROM AUTHOR]

Soil microorganisms play a crucial role in maintaining soil ecosystem health. Their metabolic processes are directly impacted by various environmental stresses caused by the increasing release of chemical pollutants and changes in the physical environment due to rapid societal development. This paper aimed to investigate the mechanisms underlying the changes in soil microbial stress responses under various external environmental stresses. The impact of pollutants on soil ecological structure was analyzed by summarizing the stress response patterns of soil microorganisms to inorganic pollutants, organic pollutants, and extreme physical environmental factors. Additionally, the migration and transformation behaviors of various complex pollutants, facilitated by the involvement of soil microorganisms, were investigated. Moreover, a novel approach was proposed for pollutant control, suggesting that manipulating the external physical field of a certain intensity could guide microbial communities and their functions towards controllable evolution within the soil environment. Therefore, this paper was essential for exploring the diversity of soil microbial stress responses, strategically regulating contaminant transport, mitigating risks associated with soil complexity, and ultimately reshaping soil ecological functions. [ABSTRACT FROM AUTHOR]

Generalized pustular psoriasis (GPP) in pregnancy can lead to severe complications for both mother and fetus. The treatment of this disease is challenging, especially in recalcitrant and severe cases. Until present, there are no evidence-based guidelines for the treatment of GPP in pregnancy. Spesolimab, a human monoclonal antibody against the IL-36 receptor, has recently attracted attention as a new therapy for GPP flare. This biologic provides rapid and sustained control of symptoms of GPP flare, although its use in pregnant women has not been reported to date. Here, we report a pregnant woman with refractory GPP who did not respond well to systemic steroids. Administration of spesolimab resulted in complete control of the disease and the birth of a healthy baby. Our case demonstrates that IL-36RN inhibitors are a potentially effective and safe treatment option for GPP in pregnancy. [ABSTRACT FROM AUTHOR]

In this paper, we consider a perturbed version of a very simple and exactly solvable model that supports Fermi arcs and pseudogap in its ground state and excitation spectrum, which includes Hubbard-like interactions in both momentum and real spaces. We find that the combined effects give rise to non-Fermi liquid behavior in the electron self-energy. This points to a novel mechanism that leads to non-Fermi liquid behavior, which is of strong current interest in the context of strongly correlated metals, that often become superconductors. Comparison will be made with phenomenology of high- temperature cuprate superconductors. [ABSTRACT FROM AUTHOR]

Background: Tinea capitis is an infection of the scalp and hair shaft caused by dermatophytes that predominantly occurs in children. Skin fungal infections have been found to be associated with alterations in the overall bacterial and fungal communities. However, the scalp microbiome in tinea capitis have not been fully investigated. Objectives: To investigate and compare the scalp bacterial and fungal microbiomes between children with tinea capitis and healthy children and between children and adults. Methods: Skin samples were collected from the scalp. Bacterial and fungal community compositions were analysed by amplification sequencing of the V3‐V4 of 16S rDNA and ITS1‐5F, respectively. Results: The predominant fungi detected using amplicon sequencing were consistent with the culture‐ or real‐time PCR‐positive pathogens in most samples. Children with tinea capitis had lower fungal and higher bacterial Shannon diversity than healthy children. A higher relative abundance of pathogenic fungi and significant alterations in the bacterial community in the lesional sites of tinea capitis than healthy scalps. Compared with adults, healthy children were characterised by higher Shannon diversities with significantly lower relative abundances of Malassezia and Cutibacterium and higher relative abundances of Candida and Streptococcus. Conclusions: We demonstrated that tinea capitis was characterised by significant alterations in both fungal and bacterial communities and amplicon sequencing could be a complementary method for pathogen identification. [ABSTRACT FROM AUTHOR]

Summary: Background: Seborrhoeic dermatitis (SD) is a common chronic inflammatory dermatosis. Current theories on the pathogenesis of SD highlight the role of microbes on the skin surface. Ketoconazole is commonly used for the treatment of SD; however, there are limited data focusing on the effects of ketoconazole in shaping the skin microbiome in patients with SD. Aim: In this prospective cohort study, we used a high‐throughput DNA sequencing method to characterize the cutaneous microbial communities of patients with SD before and after topical ketoconazole treatment. Methods: In total, 30 patients with facial SD and 15 age‐ and sex‐matched healthy controls (HCs) were enrolled in this study. Skin swabs were collected from SD lesional sites of the cheek at baseline, after ketoconazole treatment and 2 weeks post‐treatment. DNA was extracted from skin samples. The bacterial 16S V3V4 rRNA and fungal internal transcribed spacer 1–5F regions were sequenced, and the microbial community compositions were analysed. Results: Significantly lower bacterial and fungal diversities were detected at the lesional sites of facial SD compared with HCs. A decreased relative abundance of Cutibacterium and increased abundances of Malassezia and Staphylococcus were found in facial SD. Disease diversity was positively correlated with the relative abundances of Malassezia, Staphylococcus and Corynebacterium, while transepidermal water loss was negatively associated with the relative abundance of Cutibacterium. After ketoconazole treatment, fungal Shannon diversity and the relative abundances of Candida and Aspergillus were significantly increased at the lesional sites, and the relative abundance of Malassezia showed a decreasing trend. These changing trends were maintained until 2 weeks post‐treatment. Conclusion: Facial SD showed lower fungal diversity accompanied by increased relative abundances of Malassezia and Staphylococcus and decreased relative abundance of Cutibacterium. Ketoconazole treatment reduced Malassezia and increased fungal diversity to restore skin microbial communities. [ABSTRACT FROM AUTHOR]

Shifts in skin microbiome are considered to be involved in the pathogenesis of psoriasis. However, data on the microbial dysbiosis of nail psoriasis are scarce. In this study, we aim to investigate and characterize the nail bacterial and fungal microbiome in patients with psoriasis. Nail samples were collected prospectively from 36 subjects with nail psoriasis, 24 psoriatic subjects without nail involvement and 32 healthy controls. Amplicon sequencing was performed to evaluate the bacterial and fungal community compositions. Significant alterations in the bacterial microbiome were found in the nail samples of psoriatic patients. The unaffected nails in psoriatic patients were associated with higher bacterial diversity, and a higher relative abundance of Enhydrobacter, whereas nail psoriasis was correlated with a decreased relative abundance of Anaerococcus. Shifts in fungal community composition were reflected by a higher proportion of Malassezia in the unaffected nails of psoriatic patients and an increased proportion of Candida in psoriatic nails. Shifts in the nail microbiome in psoriasis suggest a potential role of microbes in the development of nail psoriasis. Future researches focusing on these microorganisms may help to explain the pathogenesis of psoriasis. [ABSTRACT FROM AUTHOR]

The failure of complex engineering systems is easy to lead to disastrous consequences. To prevent the failure, it is necessary to model complex engineering systems using probabilistic techniques with limited data which is a major feature of complex engineering systems. It is a good choice to perform such modeling using Bayesian network because of its advantages in probabilistic modeling. However, few Bayesian network structural learning algorithms are designed for complex engineering systems with limited data. Therefore, an algorithm for learning the Bayesian network structure of them should be developed. Based on the process of self-purification of water, a complex engineering system is segmented into three components according to the degree of difficulty in solving them. And then a Bayesian network learning algorithm with three components (TC), including PC algorithm, MIK algorithm which is originated by the paper through combining Mutual Information and K2 algorithm, and the Hill-Climbing method, is developed, i.e. TC algorithm. To verify its effectiveness, TC algorithm, K2 algorithm, and Max-Min Hill-Climbing are respectively used to learn Alarm network with different sizes of samples. The results imply that TC algorithm has the best performance. Finally, TC algorithm is applied to study tank spill accidents with 220 samples. [ABSTRACT FROM AUTHOR]

Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease with an increasing prevalence worldwide. The aetiology and pathogenesis of AD have not been fully elucidated. Previous studies have suggested the role of fungi as a triggering factor in the development AD. Here we conducted a systematic review to investigate the skin mycobiome profiles in AD and to address whether there is an association between fungal dysbiosis and AD. We searched Medline/PubMed, Embase and Web of Science for research studies published in English between January 1st, 2010 and April 21st, 2021. A total of 11 human studies and 3 animal studies were included in this analysis. Fungal dysbiosis was observed in AD lesions with a depleted amount of Malassezia and a higher abundance of filamentous fungi. A positive correlation between Candida and Staphylococcus was also demonstrated in AD. We supposed that specific species of Malassezia spp. and Candida spp. may play a role in the pathogenesis of AD by interacting with the pathogenic bacteria. Topical application of emollients could improve the skin barrier function and restore the skin fungal flora by increasing the amount of Malassezia. Further studies focusing on the complex interplay between specific skin fungi and the host can provide better insight into the role of microorganisms in the pathogenesis of AD. [ABSTRACT FROM AUTHOR]

Objective: Thyroid dysfunction is associated with an elevated risk of cognitive decline, but the mechanism underlying this relationship is elusive. In this study, we investigate the relationships between free thyroxine (FT4), brain frailty and clock drawing test (CDT) performance in patients with acute minor stroke or transient ischaemic attack (TIA). Design, Patients and Measurements: A total of 204 consecutive patients admitted to our hospital within 72 h after the onset of acute minor stroke or TIA were prospectively enroled and categorized in terms of quartiles of FT4 between March 2018 and August 2019. Brain frailty on magnetic resonance imaging was rated according to previously published criteria. Cognitive performance was assessed with the CDT. Results: Generalized linear analysis revealed that FT4 was independently associated with higher brain frailty score after adjusting potential confounders (β, 0.03; 95% confidence interval [CI], 0.00–0.06; p = 0.0205), which is consistent with the result of FT4 (quartile) as a categorical variable (β, 0.34; 95% CI, 0.01–0.68; p = 0.0059; ptrend = 0.0807). A nonlinear relationship was detected between FT4 and brain frailty score, which had an inflection point of 1.19. FT4 was also associated with poor CDT performance (odds ratio, 1.15; 95% CI, 1.04–1.26; p = 0.0051). And mediation analysis found that brain frailty partially mediated the positive relationship between FT4 and poor CDT performance (indirect effect = 0.0024; 95% CI, 0.0003–0.01, p = 0.04). Conclusions: Our findings suggested that a higher FT4 level was associated with a higher brain frailty score and poorer CDT performance, and brain frailty might play an important effect on the association between FT4 and cognitive decline. [ABSTRACT FROM AUTHOR]

Microbes use signal transduction systems in the processes of swarming motility, antibiotic resistance, virulence, conjugal plasmid transfer, and biofilm formation. However, the signal transduction systems in natural marine biofilms have hardly been profiled. Here we analyzed signal transduction genes in 101 marine biofilm and 91 seawater microbial metagenomes. The abundance of almost all signal transduction-related genes in biofilm microbial communities was significantly higher than that in seawater microbial communities, regardless of substrate types, locations, and durations for biofilm development. In addition, the dominant source microbes of signal transduction genes in marine biofilms were different from those in seawater samples. Co-occurrence network analysis on signal communication between microbes in marine biofilms and seawater microbial communities revealed potential inter-phyla interactions between microorganisms from marine biofilms and seawater. Moreover, phylogenetic tree construction and protein identity comparison displayed that proteins related to signal transductions from Red Sea biofilms were highly similar to those from Red Sea seawater microbial communities, revealing a possible biological basis of interspecies interactions between surface-associated and free-living microbial communities in a local marine environment. Our study revealed the special profile and enrichment of signal transduction systems in marine biofilms and suggested that marine biofilms participate in intercellular interactions of the local ecosystem where they were seeded. [ABSTRACT FROM AUTHOR]

Background: Onychomycosis (OM) is the most common infectious nail disease, and it occurs frequently in patients with psoriasis. Microbial community shifts have been suggested to play a role in psoriasis and fungal infection occurrence. Objectives: To investigate and compare nail microbial community compositions in psoriatic and nonpsoriatic patients with OM. Methods: Toenail samples were collected from nonpsoriatic patients with OM, psoriatic patients with nail psoriasis (NP) and OM, patients with only NP and healthy controls. Bacterial and fungal community compositions were analysed by amplicon sequencing of the V3‐V4 regions of the 16S rDNA gene and the ITS1 region, respectively. Results: Psoriatic OM patients had higher bacterial and fungal alpha diversities. Taxonomic analysis revealed a significantly lower relative abundance of Trichophyton rubrum (32.88% vs 82.18%, p <.001) and an increased trend of the abundance of Candida in psoriatic patients with OM than in nonpsoriatic patients. Nonpsoriatic patients with OM had a higher abundance of Staphylococcus than healthy controls (59.66% vs 45.76%, p <.05). Trichophyton, Alternaria and Malassezia could accurately differentiate psoriatic and nonpsoriatic patients with OM, with an area under the curve (AUC) of 0.86. The severity of OM was positively correlated with the relative abundance of Trichophyton rubrum. Further, Trichophyton was positively correlated with Staphylococcus and negatively correlated with Corynebacterium, Anaerococcus, Malassezia and Alternaria. Conclusions: The nail microbiome in psoriatic patients with OM has distinct bacterial and fungal signatures, suggesting that different dysbiosis is associated with the pathogenesis of OM in psoriatic and nonpsoriatic patients. [ABSTRACT FROM AUTHOR]

Seborrheic dermatitis (SD) and dandruff (DF) are common chronic inflammatory skin diseases characterized by recurrent greasy scales, sometimes with erythema and itchiness. Although the exact pathophysiology of the disease is still unclear, current theories highlight the role of microbes on the skin surface in the pathogenesis of SD. Here, we conducted a systematic review to investigate the skin microbiome alterations in patients with SD/DF. We searched Medline/PubMed, Embase and Web of Science for research studies published in English between 1 January 2000 and 31 December 2020. A total of 12 studies with 706 SD/DF samples and 379 healthy samples were included in this study. The scalp and face were predominated by the fungi of Ascomycota and Basidiomycota and the bacteria of Actinobacteria and Firmicutes. In general, the included studies demonstrated an increased Malassezia restricta/Malassezia globosa ratio and a reduction in the Cutibaterium/Staphylococcus ratio in the setting of SD/DF. Staphylococcus was associated with epidermal barrier damage, including elevated levels of trans‐epidermal water loss and pH, while Cutibacterium had a positive correlation with water content. Malassezia was also found to be related to an increased itching score and disease severity. Further studies focusing on the interactions between various microbes and the host and microbes can help us to better understand the pathogenesis of SD/DF. [ABSTRACT FROM AUTHOR]

Human errors are considered to be the main causation factors of high-temperature molten metal accidents in metallurgical enterprises. The complex working environment of high- temperature molten metal in metallurgical enterprises has an important influence on the reliability of human behavior. A review of current human reliability techniques confirms that there is a lack of quantitative analysis of human errors in high-temperature molten metal operating environments. In this paper, a model was proposed to support the human reliability analysis of high-temperature molten metal operation in the metallurgy industry based on cognitive reliability and error analysis method (CREAM), fuzzy logic theory, and Bayesian network (BN). The comprehensive rules of common performance conditions in conventional CREAM approach were provided to evaluate various conditions for high-temperature molten metal operation in the metallurgy industry. This study adopted fuzzy CREAM to consider the uncertainties and used the BN to determine the control mode and calculate human error probability (HEP). The HEP for workers involved in high-temperature melting in steelmaking production process was calculated in a case with 13 operators being engaged in different high-temperature molten metal operations. The human error probability of two operators with different control modes was compared with the calculation result of basic CREAM, and the result showed that the method proposed in this paper is validated. This paper quantified point values of human error probability in high-temperature molten metal operation for the first time, which can be used as input in the risk evaluation of metallurgical industry. [ABSTRACT FROM AUTHOR]

Comparison of the skin microbiome between psoriasis and SD reveal distinct pattern of microbial community alterations, especially in the level of I Streptococcus i , I Corynebacterium i , I Psychrobacter i and I Candida i . Keywords: psoriasis; seborrheic dermatitis; skin microbiome EN psoriasis seborrheic dermatitis skin microbiome 1116 1118 3 07/18/22 20220701 NES 220701 Dear Editor, Psoriasis and seborrheic dermatitis (SD) are common skin inflammatory diseases, which were difficult to discriminate due to similar clinical features, especially when the scalp is the only area involved. [Extracted from the article]

Dermatophyte infections usually present as various types of superficial cutaneous mycoses; on very rare occasions, dermatophytes enter deep into the dermis and cause invasive infections. In this study, we aimed to perform a systematic review of all reported invasive dermatophytosis cases over the past 20 years. We performed systematic searches in PubMed/Medline, EMBASE and Web of Science and identified 123 papers reporting 160 individual cases of invasive dermatophytosis between 2000 and 2020. Our study included 103 (64.4%) males, and the mean age at diagnosis was 43.0 years (range: 3–87 years). The most common predisposing factor was superficial dermatophytosis (56.9%), followed by solid organ transplantation (26.9%), the use of topical immunosuppressants (15.6%), gene mutations (14.4%), diabetes (14.4%) and trauma (6.9%). Trichophyton (T.) rubrum was the most prevalent pathogen (53.1%) responsible for invasive dermatophytosis, followed by T. mentagrophytes (7.5%), Microsporum canis (6.9%), T. tonsurans (5.6%), T. interdigitale (5.0%) and T. violaceum (3.8%). Patients with CARD9 or STAT3 mutations were prone to have mixed infection of two or more dermatophytes, present with eosinophilia and high IgE, and develop disseminated infections. Overall mortality was 7.9%, and the mortality in patients with and without gene mutations was 17.4% and 5.5%, respectively. Most of the normal host patients responded well to oral antifungal agents, while gene‐deficient patients usually required lifelong treatment to stabilise their infection status. Our review indicated the importance of preventive treatment of superficial tinea in patients with immunosuppression and gene deficiencies to avoid the development of invasive dermatophytosis. [ABSTRACT FROM AUTHOR]

Microbes respond to environmental stimuli through complicated signal transduction systems. In microbial biofilms, because of complex multiple species interactions, signals transduction systems are of an even higher complexity. Here, we performed a signal-molecule-treatment experiment to study the role of different signal molecules, including N-hexanoyl-L-homoserine lactone (C6-HSL), N-dodecanoyl-L-homoserine lactone (C12-HSL), Pseudomonas quinolone signal (PQS), and cyclic di-GMP (c-di-GMP), in the development of marine biofilms. Comparative metagenomics suggested a distinctive influence of these molecules on the microbial structure and function of multi-species biofilm communities in its developing stage. The PQS-treated biofilms shared the least similarity with the control and initial biofilms. The role of PQS in biofilm development was further explored experimentally with the strain Erythrobacter sp. HKB8 isolated from marine biofilms. Comparative transcriptomic analysis showed that 314 genes, such as those related to signal transduction and biofilm formation, were differentially expressed in the untreated and PQS-treated Erythrobacter sp. HKB8 biofilms. Our study demonstrated the different roles of signal molecules in marine biofilm development. In particular, the PQS-based signal transduction system, which is frequently detected in marine biofilms, may play an important role in regulating microbe-microbe interactions and the assemblage of biofilm communities. [ABSTRACT FROM AUTHOR]

Of the ~80 putative toxin‐antitoxin (TA) modules encoded by the bacterial pathogen Mycobacterium tuberculosis (Mtb), three contain antitoxins essential for bacterial viability. One of these, Rv0060 (DNA ADP‐ribosyl glycohydrolase, DarGMtb), functions along with its cognate toxin Rv0059 (DNA ADP‐ribosyl transferase, DarTMtb), to mediate reversible DNA ADP‐ribosylation (Jankevicius et al., 2016). We demonstrate that DarTMtb‐DarGMtb form a functional TA pair and essentiality of darGMtb is dependent on the presence of darTMtb, but simultaneous deletion of both darTMtb‐darGMtb does not alter viability of Mtb in vitro or in mice. The antitoxin, DarGMtb, forms a cytosolic complex with DNA‐repair proteins that assembles independently of either DarTMtb or interaction with DNA. Depletion of DarGMtb alone is bactericidal, a phenotype that is rescued by expression of an orthologous antitoxin, DarGTaq, from Thermus aquaticus. Partial depletion of DarGMtb triggers a DNA‐damage response and sensitizes Mtb to drugs targeting DNA metabolism and respiration. Induction of the DNA‐damage response is essential for Mtb to survive partial DarGMtb‐depletion and leads to a hypermutable phenotype. [ABSTRACT FROM AUTHOR]

In the ultimatum game (UG), mid-value offers are unfair but not so unreasonable as to be rejected immediately. As a consequence, they are difficult for responders to evaluate because of the conflict that arises between two key processes, namely inequity aversion and self-interests. Since there is no clear consensus in the literature on event-related potential (ERP) as to how mid-value offers are processed, we designed an experiment to explore how the ability to reject offers influences key ERP signatures. By manipulating the right to reject offers based on game type (ultimatum game, UG or dictator game, DG), our study explored how ERPs were influenced by three types of offers available to participants (fair, unfair and mid-value). We recorded the electroencephalogram results of 28 participants while they responded to the three kinds of offers in the UG and the DG. We observed that mid-value offers in the UG elicited more negative feedback-related negativity and N400 than did the unfair offers. However, these ERP patterns were specific to the UG. Furthermore, we interpreted these results as further electrophysiological evidence of the interaction between the two processing systems during the UG. [ABSTRACT FROM AUTHOR]

Bacteria produce metamorphosis-associated contractile (MAC) structures to induce larval metamorphosis in Hydroides elegans. The distribution and diversity of mac gene homologs in marine environments are largely unexplored. In the present study mac genes were examined in marine environments by analyzing 101 biofilm and 91 seawater metagenomes. There were more mac genes in biofilms than in seawater, and substratum type, location, or sampling time did not affect the mac genes in biofilms. The mac gene clusters were highly diverse and often incomplete while the three MAC components co-occurred with other genes of different functions. Genomic analysis of four Pseudoalteromonas and two Streptomyces strains revealed the mac genes transfers among different microbial taxa. It is proposed that mac genes are more specific to biofilms; gene transfer among different microbial taxa has led to highly diverse mac gene clusters; and in most cases, the three MAC components function individually rather than forming a complex. [ABSTRACT FROM AUTHOR]

Mycobacterium tuberculosis (Mtb) must cope with exogenous oxidative stress imposed by the host. Unlike other antioxidant enzymes, Mtb’s thioredoxin reductase TrxB2 has been predicted to be essential not only to fight host defenses but also for in vitro growth. However, the specific physiological role of TrxB2 and its importance for Mtb pathogenesis remain undefined. Here we show that genetic inactivation of thioredoxin reductase perturbed several growth-essential processes, including sulfur and DNA metabolism and rapidly killed and lysed Mtb. Death was due to cidal thiol-specific oxidizing stress and prevented by a disulfide reductant. In contrast, thioredoxin reductase deficiency did not significantly increase susceptibility to oxidative and nitrosative stress. In vivo targeting TrxB2 eradicated Mtb during both acute and chronic phases of mouse infection. Deliberately leaky knockdown mutants identified the specificity of TrxB2 inhibitors and showed that partial inactivation of TrxB2 increased Mtb’s susceptibility to rifampicin. These studies reveal TrxB2 as essential thiol-reducing enzyme in Mtb in vitro and during infection, establish the value of targeting TrxB2, and provide tools to accelerate the development of TrxB2 inhibitors. [ABSTRACT FROM AUTHOR]

The identification of Mycobacterium tuberculosis genes necessary for persistence in vivo provides insight into bacterial biology as well as host defense strategies. We show that disruption of M. tuberculosis membrane protein PerM (Rv0955) resulted in an IFN-γ-dependent persistence defect in chronic mouse infection despite the mutant’s near normal growth during acute infection. The perM mutant required increased magnesium for replication and survival; incubation in low magnesium media resulted in cell elongation and lysis. Transcriptome analysis of the perM mutant grown in reduced magnesium revealed upregulation of cell division and cell wall biosynthesis genes, and live cell imaging showed PerM accumulation at the division septa in M. smegmatis. The mutant was acutely sensitive to β-lactam antibiotics, including specific inhibitors of cell division-associated peptidoglycan transpeptidase FtsI. Together, these data implicate PerM as a novel player in mycobacterial cell division and pathogenesis, and are consistent with the hypothesis that immune activation deprives M. tuberculosis of magnesium. [ABSTRACT FROM AUTHOR]

BACKGROUND Rhizoma dioscorea, Lycium barbarum, Prunella vulgaris and hawthorn are well known in both traditional food and folk medicine. Each of these plants reportedly possesses beneficial effects in the treatment of diabetes. In this study an anti-diabetic health-promoting diet was formulated by mixing the herbs in a ratio of 6:4:2:3, and the anti-diabetic effect and underlying mechanism were elucidated in vivo. RESULTS Compared with the model control group, the formula, especially its ethanol extract ( EF), could improve glucose intolerance and normalize the lipid profile. The mechanisms responsible for the amelioration of glucose and lipid metabolism in mice were an increase in peripheral and hepatic insulin sensitivity, a decrease in serum free fatty acid level, enhanced hepatic glucokinase activity and glycogen content and improved serum antioxidant activity. Hepatic histopathological examination also showed that EF administration markedly decreased fatty deposits in the liver of mice. CONCLUSION The results of the present study demonstrated that the prepared functional formula diet is a potent alternative as an anti-diabetic health-promoting diet. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

CCAAT/enhancer binding protein homologous protein (CHOP) expression increases when Na+-H+ exchanger 1 (NHE1) is inhibited. Endoplasmic reticulum (ER) stress has been shown to trigger tumor cell death through CHOP. We therefore hypothesized that NHE1 activity correlates with ER stress and confers pharmaceutical potential to NHE1 inhibitor as an anti-tumor agent. The present study showed that treatment with the NHE1 inhibitor cariporide led to ER stress-induced up-regulation of the death receptor 5 (DR5) which is mediated by CHOP at the transcriptional level. We also determined that ER stress-induced Janus kinase (JNK) activation was responsible for the modulation of CHOP. Combining cariporide with tumor necrosis factor related apoptosis-inducing ligand (TRAIL) led to a significantly enhanced level of apoptosis that was abrogated by siRNA silencing of CHOP. This study provides a potential mechanistic rationale for the use of NHE1 inhibitor in combination with DR5 agonists to induce apoptosis in leukemia. [ABSTRACT FROM AUTHOR]

BACKGROUND Kombucha tea ( KT), a traditional health beverage containing potential hepatoprotective agents, is fermented from sugared tea by a symbiotic culture of yeast and bacteria for 8 days. However, the functional strains that produce components for the hepatoprotective property of KT remain unclear. Multiple strains are involved in traditional KT production. Therefore, KT has not been standardized or produced commercially. This study aimed to identify the functional strains and quantify the functional components with hepatoprotective effects in kombucha tea. RESULTS Gluconacetobacter sp. A4 was one of the microorganisms in KT in which the d-saccharic acid-1,4-lactone ( DSL) produced by G. sp. A4 was significantly higher than that produced by original tea fungus at 8 days of fermentation. Traditional KT ( TKT, tea broth fermented by mixed tea fungus), modified KT ( MKT, fermented by single G. sp. A4), and DSL significantly inhibited the acetaminophen-induced increase of alanine aminotransferase, alkaline phosphatase, triglyceride and malondialdehyde, as well as facilitating the reduction of total antioxidant capacity in mice. Furthermore, MKT and TKT are both similar to DSL in terms of protection against acetaminophen-induced liver injury in mice. These results suggested a positive relationship between DSL content and the hepatoprotective effect of TKT, MKT and DSL groups. CONCLUSION G. sp. A4 was concluded to be a potential functional strain and DSL might be the key functional component for the hepatoprotective property in KT. The stronger capability of G. sp. A4 in producing DSL makes it a better choice for the commercial production of KT. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Biofilms are surface-attached multicellular communities that play critical roles in inducing biofouling and biocorrosion in the marine environment. Given the serious economic losses and problems caused by biofouling and biocorrosion, effective biofilm control strategies are highly sought after. In a screening program of antibiofilm compounds against marine biofilms, we discovered the potent biofilm inhibitory activity of elasnin. Elasnin effectively inhibited the biofilm formation of seven strains of bacteria isolated from marine biofilms. With high productivity, elasnin-based coatings were prepared in an easy and cost-effective way, which exhibited great performance in inhibiting the formation of multi-species biofilms and the attachment of large biofouling organisms in the marine environment. The 16S amplicon analysis and anti-larvae assay revealed that elasnin could prevent biofouling by the indirect impact of changed microbial composition of biofilms and direct inhibitory effect on larval settlement with low toxic effects. These findings indicated the potential application of elasnin in biofilm and biofouling control in the marine environment. [ABSTRACT FROM AUTHOR]