Inflammation and endothelial function relevant genetic polymorphisms, carotid atherosclerosis, and vascular events in high-risk stroke population.

Aim: To identify the associations of 19 single nucleotide polymorphisms (SNPs) in genes involved in inflammation and endothelial function and carotid atherosclerosis with subsequent ischemic stroke and other vascular events in the high-risk stroke population. Methods: This was a multicenter community-based sectional survey and prospective cohort study in Sichuan, southwestern China. Eight communities were randomly selected, and the residents in each community were surveyed using a structured face-to-face questionnaire. Carotid ultrasonography and DNA information were obtained from 2,377 out of 2,893 individuals belonging to a high-risk stroke population. Genotypes of the 19 SNPs in genes involved in inflammation and endothelial function were measured. All the 2,377 subjects were followed up for 4.7 years after the face-to-face survey. The primary outcome was ischemic stroke, and the secondary outcome was a composite of vascular events. Results: Among the 2,377 subjects, 2,205 (92.8%) completed a 4.7-year follow-up, 947 (42.9%) had carotid atherosclerosis [372 (16.9%) carotid vulnerable plaque, 405 (18.4%) mean IMT > 0.9 mm, 285 (12.0%) carotid stenosis ≥15%]. Outcomes occurred in 158 (7.2%) subjects [92 (4.2%) ischemic stroke, 17 (0.8%) hemorrhagic stroke, 48 (2.2%) myocardial infarction, and 26 (1.2%) death] during follow-up. There was a significant gene-gene interaction among ITGA2 rs1991013, IL1A rs1609682, and HABP2 rs7923349 in the 19 SNPs. The multivariate logistic regression model revealed that carotid atherosclerosis and the high-risk interactive genotypes among the three SNPs were independent with a higher risk for ischemic stroke (OR = 2.67, 95% CI: 1.52-6.78, p = 0.004; and OR = 3.11, 95% CI: 2.12-9.27, p < 0.001, respectively) and composite vascular events (OR = 3.04, 95% CI: 1.46-6.35, p < 0.001; and OR = 3.23, 95% CI: 1.97-8.52, p < 0.001, respectively). Conclusion: The prevalence of carotid atherosclerosis was shown to be very high in the high-risk stroke population. Specific SNPs, interactions among them, and carotid atherosclerosis were independently associated with a higher risk of ischemic stroke and other vascular events.

Serum neurofilament light chain: a predictive marker for outcomes following mild-to-moderate ischemic stroke.

Background: Biomarkers that reflect brain damage or predict functional outcomes may aid in guiding personalized stroke treatments. Serum neurofilament light chain (sNfL) emerges as a promising candidate for fulfilling this role. Methods: This prospective, observational cohort investigation included 319 acute ischemic stroke (IS) patients. The endpoints were the incidence of early neurological deterioration (END, an elevation of two or more points in the National Institute of Health stroke scale score within a week of hospitalization compared with the baseline) and functional outcome at 3 months (an mRS score of >2 at 3 months was categorized as an unfavorable/poor functional outcome). The association of sNfL, which was assessed within 24 h of admission, with END and unfavorable functional outcomes at follow-up was assessed via multivariate logistic regression, whereas the predictive value of sNfL for unfavorable functional outcomes and END was elucidated by the receiver operating characteristic curve (ROC). Results: Of 319 IS individuals, 89 (27.90%) suffered from END. sNfL not only reflects the severity of stroke measured by NIHSS score (p < 0.05) but also closely related to the severity of age-related white matter changes. Higher initial NIHSS score, severe white matter lesions, diabetes mellitus, and upregulated sNfL were significant predictors of END. Similarly, the multivariate logistic regression analysis results showed that elevated sNfL, a higher baseline NIHSS score, and severe white matter lesions were substantially linked with unfavorable outcomes for 3 months. Similarly, sNfL was valuable for the prediction of the 3 months of poor outcome (95%CI, 0.504-0.642, p = 0.044). Kaplan-Meier analysis shows that patients with elevated sNfL levels are more likely to reach combined cerebrovascular endpoints (log-rank test p < 0.05). Conclusion: This investigation suggests that sNfL can serve as a valuable biomarker for predicting END and 3-month poor functional outcomes after an IS and has the potential to forecast long-term cardiovascular outcomes.

Time to surgery after completion of neoadjuvant chemotherapy does not negatively impact recurrence and survival outcomes in breast cancer patients.

BACKGROUND: The effect of time to surgery after completion of neoadjuvant chemotherapy and outcomes in breast cancer patients remains poorly defined. Acceptable time to surgery has frequently been arbitrarily defined as between four to eight weeks. This study aims to ascertain if time to surgery after completion of neoadjuvant chemotherapy impacts disease-free survival (DFS) and overall survival (OS). MATERIALS AND METHODS: This single-institution retrospective study included patients who underwent neoadjuvant therapy and subsequent surgery from 2006 to 2017. Demographic, clinicopathological factors, and surgical data from 259 patients were analyzed. 105 patients received surgery within 28 days (group 1). 128 patients received surgery within 29-56 days (group 2), and 26 patients received surgery after 57 days or more (group 3). DFS and OS among the three groups were compared. RESULTS: Age, race, pre-chemotherapy stage, tumor type, grade, hormone receptor status, Her2 status, focality, lymphovascular invasion, radiological response to chemotherapy, type of surgery, pathological response to chemotherapy, and receipt of adjuvant radiotherapy were not significantly different between the three groups. Only receipt of adjuvant chemotherapy was statistically significant (p = 0.0230). DFS and OS between the three groups were not found to be significantly different (p = 0.520 and p = 0.369, respectively). CONCLUSION: Time to surgery after completion of neoadjuvant chemotherapy did not appear to affect recurrence or survival outcomes. Findings from this study may allow more flexibility and reduce the burden of scheduling patients for surgery within the usual four-to-eight-week window in centers with resource and scheduling constraints.

A meta-analysis of idiopathic granulomatous mastitis treatments for remission and recurrence prevention.

Purpose: The major aim of our meta-analysis was to review the effectiveness of various treatment modalities for achieving successful remission and preventing recurrence for women with idiopathic granulomatous mastitis (IGM). This knowledge is instrumental in developing evidence-based guidelines for clinicians to improve management strategies and outcomes for patients with IGM. Methods: A systematic literature search was performed on MEDLINE (Ovid), Embase (Elsevier), PubMed, Cochrane Library, Web of Science, and Google Scholar; studies published to 19 January 2022 were included. A meta-analysis of 57 observational studies was performed. The results of two randomized controlled trials were also examined. Results: There were 3,035 IGM patients across the observational and randomised studies. Overall recurrence and remission rates across all treatment strategies in 59 studies are 87.9% (2,667/3035) and 13.5% (359/2667), respectively. The studies reported 19 different treatment strategies, comprising observation, medical monotherapies, surgery, and combinations involving medical therapies, with and without surgery. Among monotherapy treatment, surgical management had the highest pooled remission rate (0.99 [95% confidence interval (CI) = 0.97-1.00]); among combination therapy, this was steroids and surgery (0.99 [0.94-1.00]). Antibiotic monotherapy had the lowest remission rate (0.72 [0.37-0.96]). The highest recurrence rates belonged to treatments that combined antibiotics and surgery (0.54 [0.02-1.00]), and antibiotics, steroids, and surgery (0.57 [0.00-1.00]). Most successful for preventing recurrence were observation (0.03 [0.00-0.10]), methotrexate (0.08 [0.00-0.24]), and steroids and surgery (0.05 [0.01-0.12]). There is a significant association between longer follow-up duration and recurrence rate reported, p = 0.002. Conclusion: Combination therapies, especially those incorporating antibiotics, steroids, and surgery, have demonstrated higher remission rates, challenging the use of antibiotic monotherapy. There is an increased emphasis on the need for personalised, multi-pronged approach for preventing IGM recurrence, with longer follow-up care. More prospective future work in IGM research, with standardised diagnostic criteria, treatment protocols, and reporting guidelines will be important for developing treatment protocols and guidelines clinicians can adhere to in the clinical management of IGM patients.Systematic review registration: PROSPERO (CRD42022301386).

Resilience of finite clusters of carbon flux network under localized attack.

The investigation into the resilience of the carbon flux network regarding its capability to sustain the normal flow and transformation of carbon under extreme climatic events, pollutant emissions, biological invasions, and other factors, and the stability of connections between its nodes, has not yet been deeply studied. In this study, we developed carbon flux network models for various regional lands using complex networks, percolation theory, and introducing time delay effects using carbon flux daily data from 2000 to 2019 for three regions: China, the mainland United States, and Europe, to measure the resilience of finite clusters with sizes greater than or equal to s of the carbon flux network under localized attack. The analysis revealed that the carbon flux networks in different regions are characterized by a degree distribution consistent with the Poisson distribution. The carbon flux network demonstrated continuous phase transition behavior under localized attack. Interestingly, numerical simulation revealed a consistent relationship between the carbon flux network and the theoretical Erdos-Rényi network model. Moreover, the carbon flux network becomes more vulnerable as s increases. In addition, we discovered that there is a general scaling relationship of critical exponent δ≈-2 between the fraction of finite clusters and s. Therefore, investigating the resilience of carbon flux networks can enable us to predict and respond to the various risks and challenges, which will help policy designers formulate appropriate response strategies and enhance carbon flux systems' stability and resilience.

Feasibility of Omitting Sentinel Lymph Node Biopsy in an Under-screened Cohort of Breast Cancer Patients With a Premastectomy Diagnosis of Ductal Carcinoma In Situ.

BACKGROUND: Nodal involvement in ductal carcinoma in situ (DCIS) is rare. In patients with DCIS diagnosis prior to mastectomy, a sentinel lymph node biopsy (SLNB) is usually performed during mastectomy, to avoid the risk of reoperation and the non-identification of SLN subsequently, should there be an upgrade to invasive cancer. We aimed to study the feasibility of omitting SLNB in an under-screened cohort, with mostly symptomatic patients and DCIS diagnosis before mastectomy, by determining the upgrade rate to invasive cancer/ DCIS microinvasion (DCISM) and its associated risk factors. METHODS: Patients with pure DCIS diagnosis premastectomy were reviewed retrospectively. Patients with known DCISM or invasive cancer before mastectomy and bilateral cancers were excluded. Patients' demographics, radiological and pathological data premastectomy were analyzed. RESULTS: A total of 189 patients were included. The mean age was 53.8 (range: 29-85) years old. About 64.4% presented with symptoms. 36.0% and 15.3% upgraded to invasive cancer and DCISM on mastectomy respectively. Palpable tumor (P = .0036), large size on ultrasound (P = .0283), tumor seen on mammogram and ultrasound (P = .0082), ultrasound-guided biopsy (P < .0001), high-grade DCIS on biopsy (P = .0350) and no open biopsy/lumpectomy before mastectomy (P < .0001) were associated with the upgrade, with the latter factor remaining significant after multivariable analysis. Nodal involvement was 8.47% and was associated with invasive cancer (P < .0001). CONCLUSION: In a cohort who had DCIS diagnosis before mastectomy and were mostly symptomatic, the upgrade rate was 51.3%. Despite the high upgrade rate, nodal involvement remained comparable. Risk factors could select patients for omission of upfront SLNB, with a delayed SLNB planned if needed.

Trade-off in the partitioning of recent photosynthate carbon under global change.

There may be trade-offs in the allocation patterns of recent photosynthetic carbon (RPC) allocation in response to environmental changes, with a greater proportion of RPC being directed towards compartments experiencing limited resource availability. Alternatively, the allocation of RPC could shift from sources to sinks as plants processing excess photosynthates. It prompts the question: Does the pattern of RPC allocation vary under global changes? If so, is this variation driven by optimal or by residual C allocation strategies? We conducted a meta-analysis by complicating 273 pairwise observations from 55 articles with 13 C or 14 C pulse or continuous labeling to assess the partitioning of RPC in biomass (leaf, stem, shoot, and root), soil pools (soil organic C, rhizosphere, and microbial biomass C) and CO2 fluxes under elevated CO2 (eCO2 ), warming, drought and nitrogen (N) addition. We propose that the increased allocation of RPC to belowground under sufficient CO2 results from the excretion of excess photosynthates. Warming led to a significant reduction in the percentage of RPC allocated to shoots, alongside an increase in roots allocation, although this was not statistically significant. This pattern is due to the reduced water availability resulting from warming. In conditions of drought, there was a notable increase in the partitioning of RPC to stems (+7.25%) and roots (+36.38%), indicative of a greater investment of RPC in roots for accessing water from deeper soil. Additionally, N addition led to a heightened allocation of RPC in leaves (+10.18%) and shoots (+5.78%), while reducing its partitioning in soil organic C (-8.92%). Contrary to the residual C partitioning observed under eCO2 , the alterations in RPC partitioning in response to warming, drought, and N supplementation are more comprehensively explained through the lens of optimal partitioning theory, showing a trade-off in the partitioning of RPC under global change.

Transcriptional regulation of the fidaxomicin gene cluster and cellular development in Actinoplanes deccanensis YP-1 by the pleiotropic regulator MtrA.

IMPORTANCE: Cascade regulation networks are almost present in various kinds of microorganisms, but locating and systematically elucidating specific pleiotropic regulators related to a certain gene cluster can be a tricky problem. Here, based on the promoter of the fidaxomicin pathway-specific regulator FadR1, we utilized a "DNA to Proteins" affinity purification method and captured a global regulator MtrA, which positively regulates fidaxomicin biosynthesis. In the mtrA overexpressed strain, the production of fidaxomicin was improved by 37% compared to the native strain. Then, we combined the "Protein to DNAs" affinity purification method (DAP-seq) with the results of RNA-seq and systematically elucidated the primary and secondary metabolic processes in which MtrA directly or indirectly participates. Thus, our work brought up a new way to improve fidaxomicin production from the perspective of global regulation and analyzed the regulatory mechanism of MtrA. Meanwhile, we provided a novel methodology for the research of cascade regulation networks and vital secondary metabolites.

Yiqi Yangjing recipe stimulates apoptosis while suppressing the energy metabolism via under-expression of PFKFB3 in A549 cells.

Background: Lung cancer is a malignant tumor associated with high morbidity and mortality. Yiqi Yangjing recipe (YYR) is a formula of traditional Chinese medicine (TCM) that is commonly used for the treatment of lung cancer with good clinical efficacy. The specific anti-cancer mechanism of YYR is still unknown. We need to embark on a more in-depth pharmacological study of YYR to determine the complex compound ingredients, which could be promoted in clinical practice to achieve efficacy in prolonging recurrent metastasis of lung cancer. Methods: The cytotoxic effects of YYR on A549 cells were evaluated by Cell Counting Kit-8 (CCK-8) assay. The PFKFB3-under-expressed and overexpressed A549 cell lines were constructed via PFK15 treatment and transfection, respectively. The effects of YYR on PFKFB3 messenger RNA (mRNA) and protein expression were detected by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot. The pro-apoptotic and anti-glycolytic abilities of YYR were measured using flow cytometry assay and hippocampal XF96 extracellular flux analyzer. An in vivo tumorigenicity assay was performed on nude mice to confirm the anti-cancer effects of YYR. Results: YYR has a noticeable cytotoxic activity on A549 cells, with the treatment with both YYR and PFK15 significantly inducing apoptosis. YYR and PFK15 treatment reduced the extracellular acidification rate (ECAR) and oxygen consumption rate (OCR) in A549 cells. Similar to PFK15, YYR can down-regulate PFKFB3 expression, and PFKFB3 overexpression suppressed the apoptosis, which was reversed by YYR. Animal experiments confirmed that YYR was able to inhibit tumor growth, induce tumor cell apoptosis, and down-regulate PFKFB3 in tumor tissues. Conclusions: This study demonstrated that YYR promoted lung cancer cell apoptosis and inhibited energy metabolism by targeting PFKFB3. Furthermore, we believe that YYR may be a suitable supplement or alternative drug for lung cancer treatment.

Vulnerable Carotid Plaque is Associated with an Increased Risk of Intracerebral Hemorrhage in Individuals at High Risk of Stroke: A Chinese Population-based Cohort Study.

OBJECTIVES: To assess the association between carotid artery plaques and the risk of incident intracerebral hemorrhage (ICH) event in high-risk individuals for stroke. METHODS: We conducted a population-based cohort study using the longitudinal participant-level data of a multicenter, cross-sectional survey in southwestern China. 2644 high-risk participants for stroke were enrolled in the year 2015. The primary outcome was new-onset ICH events during a five-year follow-up period. Multivariate logistic regression was performed to identify the association between carotid plaque and new-onset ICH. Stratified analyses and interaction tests were conducted to identify variables that might modify the association between vulnerable carotid plaque and ICH. RESULTS: Among 2644 high-risk individuals enrolled, carotid plaques were found in 904 (34.2%) subjects, including 479 (18.1%) with stable plaques and 425 (16.1%) with vulnerable plaques. During a five-year follow-up period, 22 (0.83%) participants developed ICH. Vulnerable carotid plaque was associated with an increased risk of new-onset ICH in multivariable analyses (adjusted RR 3.72, 95 % CI 1.32 to 10.46, p=0.013). Stratified analyses and interaction analyses demonstrated the association between vulnerable carotid plaque and ICH was not changed by age, family history of stroke, hemorrhagic stroke and chronic disease, smoking, drinking, physical activity, BMI, antihypertensives, and antithrombotic drugs (all p for interaction>0.05). However, among the female cohort, participants with vulnerable plaques had a significantly higher risk of ICH compared with participants without vulnerable plaques (crude RR=9.8; 95%CI: 3.1-31.3, p<0.001; adjusted RR=26.3, 95%CI: 5.5-124.5, p<0.001), but not in man (p>0.05). CONCLUSION: In Chinese individuals at high risk of stroke, vulnerable carotid artery plaques are associated with an increased risk of intracerebral hemorrhage independent of classical vascular risk factors, especially in female individuals.

Can the size of chest wall recurrence after mastectomy in breast cancer patients predict the presence of systemic metastasis?

Background: One of the manifestations of recurrence after mastectomy is the presentation of chest wall lesion. However, it is unclear if the size of the chest wall recurrence (CWR) is related to the presence of simultaneous systemic metastasis in these patients. We aimed to determine if the size of the CWR could affect the outcome in these patients. Methods: Stage I-III breast cancer patients who underwent mastectomy and developed invasive ipsilateral CWR were included. Patients with bilateral mastectomy were excluded. Demographic, radiologic and pathological data were analysed between patients with CWR and simultaneous systemic metastasis versus those with isolated CWR. Results: Of the 1,619 patients treated with mastectomy, 214 (13.2%) patients developed recurrences. 57/214 (26.6%) patients had invasive ipsilateral CWR. 48 patients were analysed after exclusion of patients with missing data. Mean age at diagnosis of first cancer and at recurrence were 55.2 years (32-84 years) and 58.5 years (34-85 years) respectively. 26/48 (54.2%) had CWR with simultaneous systemic metastasis. Mean CWR size was 30.7 mm (6-121 mm) and 21.4 mm (5.3-90 mm) for the patients with simultaneous systemic metastasis and those without respectively (P=0.441). Grade (P=0.0008) and nodal status (P=0.0009) at primary diagnosis, grade (P=0.0011) and progesterone receptor (PR) status (P=0.0487) at recurrence were statistically significant for systemic metastasis in patients with CWR. Conclusions: Biologic factors such as grade of primary and recurrent cancer, PR status of recurrent cancer and nodal status at primary diagnosis, instead of CWR size, were associated with simultaneous systemic metastasis in patients with CWR.

Variants in genes related to inflammation and endothelial function can increase the risk for carotid atherosclerosis in southwestern China.

Aim: To investigate the potential association between polymorphisms in genes involved in endothelial function, inflammation and carotid atherosclerosis. Methods: This was a three-center, population-based sectional survey conducted in Sichuan province of southwestern China. We randomly selected 8 different communities in Sichuan, and the residents in each community volunteered to participate in the survey by face-to-face questionnaire. A total of 2,377 residents with high stroke risk population in the 8 communities were included. Carotid atherosclerosis was evaluated by carotid ultrasound, and the 19 single nucleotide polymorphisms (SNPs) in 10 endothelial function as well as inflammation relevant genes were measured in the high stroke risk population. Carotid atherosclerosis was defined by the presence of carotid plaque or any carotid stenosis ≥15% or mean intima-media thickness (IMT) > 0.9 mm. Generalized multifactor dimensionality reduction (GMDR) approach was used to analyze gene-gene interactions among the 19 SNPs. Results: Among the 2,377 subjects with high stroke risk, 1,028 subjects had carotid atherosclerosis (43.2%), of which 852 (35.8%) cases had carotid plaque, 295 (12.4%) cases had ≥15% carotid stenosis, whereas 445 (18.7%) had mean IMT > 0.9 mm. Multivariate logistic regression revealed that IL1A rs1609682 TT and HABP2 rs7923349 TT served as independent risk factors for carotid atherosclerosis (OR, 1.45, 95% CI: 1.034-2.032, p = 0.031, and OR, 1.829, 95% CI: 1.228-2.723, p = 0.003). GMDR analysis indicated that there was a significant gene-gene interaction found among IL1A rs1609682, ITGA2 rs1991013, and HABP2 rs7923349. After adjusting the covariates, the high-risk interactive genotypes in the 3 variants were significantly associated with a significantly higher risk for carotid atherosclerosis (OR, 2.08, 95% CI: 1.257-5.98, p < 0.001). Conclusion: The prevalence of carotid atherosclerosis was observed to be extremely high in the high-risk stroke population in southwestern China. There were associations observed between the specific variants in inflammation and endothelial function relevant genes and carotid atherosclerosis. The high-risk interactive genotypes among IL1A rs1609682, ITGA2 rs1991013, and HABP2 rs7923349 significantly increased the risk of carotid atherosclerosis. These results are expected to provide novel strategies for the prevention of carotid atherosclerosis. The gene-gene interactive analysis used in this study may be very helpful to elucidate complex genetic risk factors for carotid atherosclerosis.

Axillary management of breast cancer patients with isolated chest wall recurrence after mastectomy.

Background: National Comprehensive Cancer Network (NCCN) guidelines on the axillary management of breast cancer patients with isolated chest wall recurrence after mastectomy are unclear. Though sentinel lymph node biopsy (SLNB) is possible and may be considered, there is limited data on its usefulness. We aimed to determine if axillary restaging surgery was required in this cohort of patients who developed operable isolated chest wall recurrences after mastectomy. Methods: Breast cancer patients treated at a tertiary institution from 1st September 2005 to 31st October 2017 and developed isolated chest wall invasive recurrences after mastectomy were retrospectively reviewed. We excluded patients with bilateral cancers, concurrent regional or distant metastases, patients without surgery for their chest wall recurrences and patients who were lost to follow-up. The demographics, pathological data and second recurrences were collected from a prospectively maintained database and compared between patients with axillary lymph node dissection (ALND), SLNB and no axillary operation. Results: Of the 1,841 patients who underwent mastectomy, 26 (1.4%) patients developed isolated chest wall recurrences. Twenty two eligible patients were analysed. The mean age at diagnosis of the recurrence was 54.7 years (range, 37-84 years). 1, 2 and 19 patients had ALND, SLNB and no axillary operation respectively. On mean follow-up of 38.3 months, no axillary recurrences were noted. Conclusions: In breast cancer patients with isolated chest wall recurrences after mastectomy, axillary restaging surgery can be safely omitted with no increased axillary recurrences on medium term follow-up. This finding could refine existing guidelines in the management of the axilla for patients with chest wall recurrences after mastectomy.

Identification and degradation of structural extracellular polymeric substances in waste activated sludge via a polygalacturonate-degrading consortium.

By maintaining the cell integrity of waste activated sludge (WAS), structural extracellular polymeric substances (St-EPS) resist WAS anaerobic fermentation. This study investigates the occurrence of polygalacturonate in WAS St-EPS by combining chemical and metagenomic analyses that identify ∼22% of the bacteria, including Ferruginibacter and Zoogloea, that are associated with polygalacturonate production using the key enzyme EC 5.1.3.6. A highly active polygalacturonate-degrading consortium (GDC) was enriched and the potential of this GDC for degrading St-EPS and promoting methane production from WAS was investigated. The percentage of St-EPS degradation increased from 47.6% to 85.2% after inoculation with the GDC. Methane production was also increased by up to 2.3 times over a control group, with WAS destruction increasing from 11.5% to 28.4%. Zeta potential and rheological behavior confirmed the positive effect which GDC has on WAS fermentation. The major genus in the GDC was identified as Clostridium (17.1%). Extracellular pectate lyases (EC 4.2.2.2 and 4.2.2.9), excluding polygalacturonase (EC 3.2.1.15), were observed in the metagenome of the GDC and most likely play a core role in St-EPS hydrolysis. Dosing with GDC provides a good biological method for St-EPS degradation and thereby enhances the conversion of WAS to methane.

Degradation mechanism of AtrA mediated by ClpXP and its application in daptomycin production in Streptomyces roseosporus.

The efficiency of drug biosynthesis depends on different transcriptional regulatory pathways in Streptomyces, and the protein degradation system adds another layer of complexity to the regulatory processes. AtrA, a transcriptional regulator in the A-factor regulatory cascade, stimulates the production of daptomycin by binding to the dptE promoter in Streptomyces roseosporus. Using pull-down assays, bacterial two-hybrid system and knockout verification, we demonstrated that AtrA is a substrate for ClpP protease. Furthermore, we showed that ClpX is necessary for AtrA recognition and subsequent degradation. Bioinformatics analysis, truncating mutation, and overexpression proved that the AAA motifs of AtrA were essential for initial recognition in the degradation process. Finally, overexpression of mutated atrA (AAA-QQQ) in S. roseosporus increased the yield of daptomycin by 225% in shake flask and by 164% in the 15 L bioreactor. Thus, improving the stability of key regulators is an effective method to promote the ability of antibiotic synthesis.

Pregnancy-associated breast cancer: a multicenter study comparing clinicopathological factors, diagnosis and treatment outcomes with non-pregnant patients.

PURPOSE: Pregnancy-associated breast cancer (PABC), defined as breast carcinoma diagnosed during pregnancy or in the first post-partum year, is one of the most common gestation-related malignancies with reported differences in tumor characteristics and outcomes. This multicenter study aims to review cases of PABC in Singapore, including their clinicopathological features, treatment, and clinical outcomes compared to non-PABC patients. METHODS: Demographic, histopathologic and clinical outcomes of 93 PABC patients obtained from our database were compared to 1424 non-PABC patients. RESULTS: PABC patients presented at a younger age. They had higher tumor and nodal stages, higher tumor grade, were more likely to be hormone receptor negative and had a higher incidence of multicentric and multifocal tumors. Histological examination after definitive surgery showed no significant difference in tumor size and number of positive lymph nodes suggesting similar neoadjuvant treatment effects. Despite this, PABC patients had worse outcomes with poorer overall survival and disease-free survival, OS (P < 0.0001) and DFS (P < 0.0001). Termination of pregnancy did not improve survival. CONCLUSION: Patients with PABC present at a higher stage with more aggressive disease and have poorer outcomes compared to non-PABC patients. Reducing delay in diagnosis and treatment may help improve survival.

Profiling Microbial Communities in Idiopathic Granulomatous Mastitis.

Idiopathic granulomatous mastitis (IGM) is a rare and benign inflammatory breast disease with ambiguous aetiology. Contrastingly, lactational mastitis (LM) is commonly diagnosed in breastfeeding women. To investigate IGM aetiology, we profiled the microbial flora of pus and skin in patients with IGM and LM. A total of 26 patients with IGM and 6 patients with LM were included in the study. The 16S rRNA sequencing libraries were constructed from 16S rRNA gene amplified from total DNA extracted from pus and skin swabs in patients with IGM and LM controls. Constructed libraries were multiplexed and paired-end sequenced on HiSeq4000. Metagenomic analysis was conducted using modified microbiome abundance analysis suite customised R-resource for paired pus and skin samples. Microbiome multivariable association analyses were performed using linear models. A total of 21 IGM and 3 LM paired pus and skin samples underwent metagenomic analysis. Bray−Curtis ecological dissimilarity distance showed dissimilarity across four sample types (IGM pus, IGM skin, LM pus, and LM skin; PERMANOVA, p < 0.001). No characteristic dominant genus was observed across the IGM samples. The IGM pus samples were more diverse than corresponding IGM skin samples (Shannon and Simpson index; Wilcoxon paired signed-rank tests, p = 0.022 and p = 0.07). Corynebacterium kroppenstedtii, reportedly associated with IGM in the literature, was higher in IGM pus samples than paired skin samples (Wilcoxon, p = 0.022). Three other species and nineteen genera were statistically significant in paired IGM pus−skin comparison after antibiotic treatment adjustment and multiple comparisons correction. Microbial profiles are unique between patients with IGM and LM. Inter-patient variability and polymicrobial IGM pus samples cannot implicate specific genus or species as an infectious cause for IGM.

Patterns of breast cancer second recurrences in patients after mastectomy.

INTRODUCTION: Little is known about second recurrences in breast cancer patients, especially in patients with mastectomy. We aimed to determine the risk factors, prevalence and patterns of second recurrence in mastectomy patients after first recurrence. METHODS: Stage I-III breast cancer patients treated at a tertiary institution from 1st September 2005 to 31st October 2017 and developed first and second recurrences after mastectomy were retrospectively reviewed. We excluded patients with bilateral cancers and patients who were lost to follow-up. The demographics, pathological and recurrence data were collected from a prospectively maintained database and analysed. RESULTS: Of the 1619 mastectomy patients, 214 (13.2%) patients developed recurrences at a mean 39.9 months from primary cancer diagnosis. 23, 8 and 183 had isolated chest wall recurrences (CWR), regional and systemic metastases, respectively. Excluding 2 CWR patients without surgery, second recurrences occurred in 3/21 (14.3%) and 3/8 (37.5%) in patients with CWR and regional metastasis at 27.7 months (range: 5-42) and 32 months (range: 18-40), respectively. In both groups, systemic metastasis as second recurrence occurred within 2 years after first recurrence, whilst locoregional second recurrences occurred later. No risk factors for second recurrence were identified. CONCLUSION: In patients with mastectomy, second recurrences occurred in 20.7% of patients with treated locoregional first recurrence, with no risk factors identified. Systemic metastases manifesting as second recurrence occurred in the first 2 years after first recurrence. Continued clinical surveillance and restaging patients in the first 2 years after first locoregional recurrence may enable early prognostication and treatment with the newer metastatic drugs.

Network resilience of non-hub nodes failure under memory and non-memory based attacks with limited information.

Previous studies on network robustness mainly concentrated on hub node failures with fully known network structure information. However, hub nodes are often well protected and not accessible to damage or malfunction in a real-world networked system. In addition, one can only gain insight into limited network connectivity knowledge due to large-scale properties and dynamic changes of the network itself. In particular, two different aggression patterns are present in a network attack: memory based attack, in which failed nodes are not attacked again, or non-memory based attack; that is, nodes can be repeatedly attacked. Inspired by these motivations, we propose an attack pattern with and without memory based on randomly choosing n non-hub nodes with known connectivity information. We use a network system with the Poisson and power-law degree distribution to study the network robustness after applying two failure strategies of non-hub nodes. Additionally, the critical threshold 1 - p and the size of the giant component S are determined for a network configuration model with an arbitrary degree distribution. The results indicate that the system undergoes a continuous second-order phase transition subject to the above attack strategies. We find that 1 - p gradually tends to be stable after increasing rapidly with n. Moreover, the failure of non-hub nodes with a higher degree is more destructive to the network system and makes it more vulnerable. Furthermore, from comparing the attack strategies with and without memory, the results highlight that the system shows better robustness under a non-memory based attack relative to memory based attacks for n > 1. Attacks with memory can block the system's connectivity more efficiently, which has potential applications in real-world systems. Our model sheds light on network resilience under memory and non-memory based attacks with limited information attacks and provides valuable insights into designing robust real-world systems.