Return to Activities of Daily Living after Breast Cancer Surgery: An Observational Prospective Questionnaire-Based Study of Patients Undergoing Mastectomy with or without Immediate Reconstruction.

Background: Patients often ask about the time taken to return to activities of daily living (ADLs) after breast surgery, but there is a lack of data to give accurate guidance. We aimed to assess the feasibility of a study to determine the time taken to return to ADLs after mastectomy with or without breast reconstruction. Materials and Methods: A prospective multicentre, self-reported questionnaire-based feasibility study of women who had undergone mastectomy ± reconstruction was performed, between Jan 2017 and Dec 2019. Women were asked to self-report when they returned to 15 ADLs with a 5-option time scale for "return to activity." Results: The questionnaire was returned by 42 patients (median [range] age: 64 [31-84]). Of these, 22 had simple mastectomy, seven mastectomy and implant reconstruction, seven mastectomy and autologous reconstruction (DIEP), and six did not specify. Overall, over 90% could manage stairs and brush hair by two weeks and 84% could get in and out of the bath by four weeks. By 1-2 months, 92% could do their own shopping and 86% could drive. 68% of women employed returned to work within four months. Compared to simple mastectomy, patients undergoing reconstruction took a longer time to return to getting in/out of bath (<2 vs. 2-4 weeks), vacuuming (2-4 weeks vs. 1-2 months), and fitness (1-2 vs. 3-4 months). There was a slower return to shopping (1-2 months vs. 2-4 weeks), driving and work (both 3-4 vs. 1-2 months), and sports (3-4 vs. 1-2 months) in autologous reconstruction compared to implant reconstruction. Conclusion: This study is feasible. It highlights slower return to specific activities (particularly strength-based) in reconstruction patients, slower in autologous compared with implant reconstruction. The impact on return to ADLs should be discussed as part of the preoperative counselling as it will inform patients and help guide their decision making. A larger study is required to confirm these results.

Vaccine microarray patch self-administration: An innovative approach to improve pandemic and routine vaccination rates.

The high-density microprojection array patch (HD-MAP) is a novel vaccine delivery system with potential for self-administered vaccination. HD-MAPs provide an alternative to needle and syringe (N&S) vaccination. Additional advantages could include reduced cold-chain requirements, reduced vaccine dose, reduced vaccine wastage, an alternative for needle phobic patients and elimination of needlestick injuries. The drivers and potential benefits of vaccination by self-administering HD-MAPs are high patient acceptance and preference, higher vaccination rates, speed of roll-out, cost-savings, and reduced sharps and environmental waste. The HD-MAP presents a unique approach in pandemic preparedness and routine vaccination of adults. It could alleviate strain on the healthcare workforce and allows vaccine administration by minimally-trained workers, guardian or subjects themselves. Self-vaccination using HD-MAPs could occur in vaccination hubs with supervision, at home after purchasing at the pharmacy, or direct distribution to in-home settings. As a result, it has the potential to increase vaccine coverage and expand the reach of vaccines, while also reducing labor costs associated with vaccination. Key challenges remain around shifting the paradigm from medical professionals administrating vaccines using N&S to a future of self-administration using HD-MAPs. Greater awareness of HD-MAP technology and improving our understanding of the implementation processes required for adopting this technology, are critical factors underpinning HD-MAP uptake by the public.

Powder plasma spheroidization treatment and the characterization of microstructure and mechanical properties of SS 316L powder and L-PBF builds.

A plasma spheroidization treatment was applied to stock stainless steel 316L powder for additive manufacturing. The normal and treated powders were compared both in the powder state as well as in the resulting laser powder bed fusion (L-PBF) builds. The plasma spheroidization process slightly increased treated powder aspect ratio and sphericity and shifted the size distribution to larger diameters relative to the normal powder. The normal powder was austenitic in nature whereas the plasma spheroidization process introduced a small fraction (∼3.5 vol %) of ferrite in the treated powder. Ferrite in the powder was not retained in the printed samples and was not shown to negatively affect the build quality. Porosity areal fraction was generally smaller in the treated powder builds. The normal powder builds had a 6% higher yield strength than treated, however the scatter was significantly larger in the 45° and horizontal orientations compared to the treated powder builds.

Evaluation of the self-administration potential of high-density microarray patches to human skin: A preliminary study.

The high-density microneedle array patch (HD-MAP) is a novel vaccine delivery system with potential for self-administered vaccination. In this study, Vaxxas HD-MAPs were applied by both a trained user and self-administered with application sites compared to determine the response of skin and the level of engagement of the HD-MAP with human skin. Twenty healthy participants were enrolled, and the response of skin including erythema was observed at all application sites and no difference was found between trained user or self-administered applications. The majority of participants (70%) preferred the deltoid upper arm application site for applying HD-MAPs. Fluorescent dermatoscope images confirmed HD-MAPs engaged the skin surface and scanning electron microscopy (SEM) image analysis exhibited similar delivery characteristics for the upper arm and forearm sites when applied by either a trained user or self-administered. This study showed that noninvasive methods including dermatoscopy and SEM image analysis were able to estimate the engagement of HD-MAPs with human skin. HD-MAP self-vaccination technology has a unique proposition in pandemic preparedness by alleviating the need for health-care workers to administer vaccines, however greater awareness and understanding of the potential of this technology is required.

Soil bacterial community dynamics in plots managed with cover crops and no-till farming in the Lower Mississippi Alluvial Valley, USA.

AIMS: Assess bacterial community changes over time in soybean (Glycine max) crop fields following cover crop (CC) and no-till (NT) implementation under natural abiotic stressors. METHOD AND RESULTS: Soil bacterial community composition was obtained by amplifying, sequencing, and analysing the V4 region of the 16S rRNA gene. Generalized linear mixed models were used to assess the effects of tillage, CC, and time on bacterial community response. The most abundant phyla present were Acidobacteria, Actinobacteria, Bacteroidetes, and Verrucomicrobia. Bacterial diversity increased in periods with abundant water. Reduced tillage (RT) increased overall bacterial diversity, but NT with a CC was not significantly different than RT treatments under drought conditions. CCs shifted abundances of Firmicutes and Bacteroidetes depending on abiotic conditions. CONCLUSIONS: In the Lower Mississippi Alluvial Valley (LMAV), USA, NT practices lower diversity and influence long-term community changes while cover crops enact a seasonal response to environmental conditions. NT and RT management affect soil bacterial communities differently than found in other regions of the country.

Improving Pain Management After Cesarean Birth Using Transversus Abdominis Plane Block With Liposomal Bupivacaine as Part of a Multimodal Regimen.

As educators, advocates, and champions for women's health, nurses play pivotal roles throughout a woman's pregnancy and childbirth journey. Most women experience postsurgical pain after cesarean birth and are prescribed opioids. Caution around opioid use warrants opioid-reducing strategies, particularly because exposure to opioids exacerbates risk for developing persistent postsurgical opioid use. Multimodal approaches can help address this concern. Regional anesthesia using transversus abdominis plane blocks with aqueous formulations of local anesthetics can reduce opioid consumption and pain but has a short duration of action. Liposomal formulation of bupivacaine prolongs its release, overcoming this obstacle. Transversus abdominis plane blocks with liposomal bupivacaine can reduce opioid use and pain after cesarean birth, improving recovery. These findings represent numerous implications for nursing practice to improve postcesarean pain management.

Circulating MiR-21 expression is upregulated after 30 days of head-down tilt bed rest.

Relative expression of miR-21-5p in serum was upregulated in response to 30 days of bed rest, and miRNA fold changes were positively associated with serum calcium changes. INTRODUCTION: Circulating miRNAs (c-miRNAs) have potential as biomarkers of cellular activity, and they may play a role in cell-to-cell communication. The purpose of this study was to examine c-miRNA and bone marker responses to a 30-day six-degree head-down bed rest protocol at an ambient 0.5% CO2. METHODS: Eleven participants (6 males/5 females, 25-50 years) had fasting blood draws taken 3 days before and immediately after completing the 30-day bed rest protocol at the Institute for Aerospace Medicine in Germany. Serum relative expression of miRNAs associated with bone function (miR-21-5p, -100-5p, -125b-5p, -126-3p) were analyzed using qPCR, and serum bone markers were quantitated using ELISA. RESULTS: Serum bone markers, sclerostin, and calcium significantly increased (p ≤ 0.036), and total hip aBMD significantly decreased (p = 0.003) post bed rest. Serum miR-21-5p relative expression was significantly upregulated (p = 0.018) post bed rest. Fold changes in miR-126-3p (r = 0.82, p = 0.002) and miR-21-5p (r = 0.62, p = 0.042) were positively correlated with absolute change in serum calcium. There were no sex differences in miRNA responses; women had greater percent increases in TRAP5b (37.3% vs. 16.9% p = 0.021) and greater percent decreases in total hip aBMD (- 2.15% vs. - 0.69%, p = 0.034) than men. CONCLUSION: c-miR-21-5p has potential as a biomarker of bone resorption and bone loss in an unloading condition. The upregulation of miR-21-5p may reflect an increase in osteoclast activity after bed rest, which is corroborated by the increase in TRAP5b.

Defining characteristics of immersion carbon dioxide gas for successful euthanasia of neonatal and young broilers.

This study investigated how the carbon dioxide (CO2) concentration within a chamber affects the efficacy of CO2 euthanasia and how the efficacy of CO2 induction methods changes as birds age. In experiment 1, pairs of broiler chicks (n = 192; 0, 3, and 6 D of age) were immersed into a chamber prefilled with 70, 80, 90, or 100% CO2. For experiment 2, 3- and 6-day-old broiler chicks (n = 88) were immersed in pairs into 100% CO2 or exposed to CO2 gradual fill in a chamber with a displacement rate of 28% chamber volume per minute. Latency to performance of headshaking (HS) and gasping (GS) as potential indicators of distress, loss of posture indicative of insensibility, and the cessation of rhythmic breathing (CRB) and cessation of movement (COM) as the indicators of death were monitored (live focal sampling/video recordings). The duration and frequency of HS and GS were assessed. For both experiments, behavior data were analyzed for CO2 method and age (4 × 3 factorial). Age and CO2 concentration interacted for latency to CRB and COM, with longer latencies for 0-day-old chicks immersed into 70% CO2 than other concentrations and ages. CO2 concentration did not affect latency to HS, GS, or loss of posture but affected CRB and COM, with latencies longest for 70% and shortest for 90 and 100% CO2. Newly hatched chicks had a longer latency to CRB and COM and longer duration and frequency of distress behaviors than older chicks. At all ages, initiation of all behaviors occurred later with gradual fill compared to immersion. There was an increased duration and frequency of distress behaviors with gradual induction compared with immersion. Overall, immersion into 90 to 100% CO2 resulted in the shortest time to insensibility and death, with a decreased duration and frequency of distress behaviors. Chicks immersed into 70% CO2 had the longest duration of GS and time to death. Age affects the efficacy of CO2 euthanasia, with increasing age decreasing time to death and the duration and frequency of distress behaviors.

2'-5'-Oligoadenylate synthetase-like protein inhibits intracellular M. tuberculosis replication and promotes proinflammatory cytokine secretion.

Host cytoplasmic surveillance pathways are known to elicit type I interferon (IFN) responses which are crucial to antimicrobial defense mechanisms. Oligoadenylate synthetase-like (OASL) protein has been extensively characterized as a part of the anti-viral mechanism, however a number of transcriptomic studies reveal its upregulation in response to infection with a wide variety of intracellular bacterial pathogens. To date, there is no evidence documenting the role (if any) of OASL during mycobacterium tuberculosis infection. Using two pathogenic strains differing in virulence only, as well as the non-pathogenic M. bovis BCG strain, we observed that pathogenicity and virulence strongly induced OASL expression after 24 h of infection. Further, we observed that OASL knock down led to a significant increase in M. tb CFU counts 96 h post-infection in comparison to the respective controls. Luminex revealed that OASL silencing significantly decreased IL-1ß, TNF-α and MCP-1 secretion in THP-1 cells and had no effect on IL-10 secretion. We therefore postulate that OASL regulates pro-inflammatory mediators such as cytokines and chemokines which suppress intracellular mycobacterial growth and survival.

Comparison of human monocyte derived macrophages and THP1-like macrophages as in vitro models for M. tuberculosis infection.

Macrophages are the preferential cell types to study various aspects of mycobacterial infection. Commonly used infection models for in-vitro studies are primary macrophages such as human monocyte derived macrophages (hMDMs) and macrophage like cell lines (THP-1). It is not clear if commercially available THP-1 cells can be used as hMDMs alternative for in-vitro M.tb infection experiments. We conducted a detailed investigation of the hMDM and THP-1 response to mycobacterial infection on a comparative basis and assess the most crucial aspects of infection which are most commonly studied. We assessed mycobacterial uptake and intracellular growth over time of a pathogenic drug-resistant and drug-susceptible M.tb strains (R179 and H37Rv) through colony forming units (CFUs). Both strains depicted similar uptake and intracellular growth in hMDMs and THP-1 macrophages over time (R179, p = 0.954) (H37Rv, p = 0.922). Cytotoxicity assays revealed a consistent viability up to day 16 post-infection across the strains in both THP-1 and hMDMs (R179, p = 0.271) (H37Rv, p = 0.068). Interestingly, both cell lines showed similar mycobacterial uptake and cellular viability in both susceptible as well as resistant M.tb strains. Cytokine/chemokine mRNA analysis through qPCR found no difference between cell types. Further, cytokine secretion measured through Luminex revealed no difference across the strains. Also, cytokine secretion analysis showed no difference in both cell lines across strains. In conclusion, our study shows that THP-1 and hMDMs bacterial uptake, viability and host response to drug-susceptible and drug-resistant mycobacterial infections are similar. Therefore, present study demonstrate that THP-1 cells are suitable substitutes for hMDMs for in-vitro M.tb infection experiments.

Bone mineral density and lean mass asymmetries are greater in cyclists than non-cyclists.

Cyclists may be at greater risk of developing asymmetrical force and motion patterns than other ground-based athletes. However, functional asymmetries during cycling tend to be highly variable, making them difficult to assess. Dual-energy x-ray absorptiometry (DXA) measurements of areal bone mineral density (aBMD) and lean mass (LM) in the lower limbs may be a more sensitive and consistent method to identify asymmetries in cyclists. The goal of this study was to determine if competitive cyclists have greater levels of asymmetries in the lower body compared to non-cyclists using DXA. A secondary aim was to determine if aBMD and LM asymmetries change over the road cycling season. 17 competitive cyclists and 21 non-cyclist, healthy controls underwent DXA scans. Lower-body asymmetries were greater in cyclists compared to non-cyclists in aBMD and LM for all lower limb segments. However, these asymmetries did not tend to consistently favour a particular side, except for the pelvis having more LM on the dominant side. The were no longitudinal changes in aBMD or LM in the cyclists. Asymmetry analysis via DXA provides evidence that although functional asymmetries during cycling are variable, cyclists have increased lower body LM and aBMD asymmetries compared to non-cyclists.

The role of low molecular weight thiols in Mycobacterium tuberculosis.

Low molecular weight (LMW) thiols are molecules with a functional sulfhydryl group that enable them to detoxify reactive oxygen species, reactive nitrogen species and other free radicals. Their roles range from their ability to modulate the immune system to their ability to prevent damage of biological molecules such as DNA and proteins by protecting against oxidative, nitrosative and acidic stress. LMW thiols are synthesized and found in both eukaryotes and prokaryotes. Due to their beneficial role to both eukaryotes and prokaryotes, their specific functions need to be elucidated, most especially in pathogenic prokaryotes such as Mycobacterium tuberculosis (M.tb), in order to provide a rationale for targeting their biosynthesis for drug development. Ergothioneine (ERG), mycothiol (MSH) and gamma-glutamylcysteine (GGC) are LMW thiols that have been shown to interplay to protect M.tb against cellular stress. Though ERG, MSH and GGC seem to have overlapping functions, studies are gradually revealing their unique physiological roles. Understanding their unique physiological role during the course of tuberculosis (TB) infection, would pave the way for the development of drugs that target their biosynthetic pathway. This review identifies the knowledge gap in the unique physiological roles of LMW thiols and proposes their mechanistic roles based on previous studies. In addition, it gives an update on identified inhibitors of their biosynthetic enzymes.

High dietary intake of whole milk and full-fat dairy products does not exert hypotensive effects in adults with elevated blood pressure.

Regular consumption of low- and nonfat dairy products reduces blood pressure (BP) in adults with elevated BP. Currently, it is unknown if conventional full-fat dairy products exert similar hypotensive effects. We hypothesized that adding full-fat dairy products to the normal routine diet would reduce seated office and ambulatory BP (primary outcome) in adults with elevated BP when compared with a no dairy control. Using a randomized controlled crossover design, 60 adults with elevated systolic BP (systolic/diastolic BP: 120-159/<99 mm Hg) participated in a 4-week high-dairy (4 servings a day of full-fat dairy products + regular diet) and a 4-week no-dairy condition (plant-based food items + regular diet) separated by a 2-week washout period. Data were analyzed based on time, condition, and sex. Seated office systolic BP did not change significantly in either condition. There were no changes in systolic BP in male or female participants across either dietary period. Ambulatory (24-hour) systolic BP did not change significantly in the high-dairy (133 ±â€¯2 vs 131 ±â€¯1 mm Hg) or no-dairy conditions (132 ±â€¯2 vs 131 ±â€¯1 mm Hg). No significant changes were observed for diastolic BP or pulse pressure during condition for office or ambulatory measures. The solitary addition of full-fat dairy products to the normal routine diet does not exert hypotensive effects in adults with elevated BP when compared to the no-dairy control.

Evaluation of carbon dioxide induction methods for the euthanasia of day-old cull broiler chicks.

This study was conducted to evaluate the efficacy of 5 different CO2 euthanasia induction techniques for day-old cull chicks in minimizing distress and inducing a rapid loss of sensibility and death. Each induction treatment was characterized for concentration change over time, maximum concentration, and time to reach maximum. Sixteen chicks were euthanized with the gradual treatments to establish validity of treatment. Then, all 5 treatments were evaluated for effect on distress, insensibility, and death. Day-of-hatch cull chicks (n = 110) were euthanized in pairs by either immersion into 100% CO2 or gradual induction to 100% CO2 at displacement rates of 7, 14, 21, or 28% of chamber volume added per min (% vol/min). CO2 concentration was measured at chick level. Live focal observations and video recordings were used to assess latency to behavioral responses: head shaking (HS) and gasping (GS) as indicators of distress; loss of posture (LOP) as an indicator of insensibility; and cessation of rhythmic breathing (CRB) and movement (COM), indicating death. All behaviors occurred at the earliest with immersion compared to gradual treatments, and time between first signs of distress and LOP was shorter for immersion than gradual treatments. Gradual treatments showed a linear decrease in latency to HS, GS, and LOP as displacement rate increased. Latency to CRB decreased quadratically with increasing displacement rate, while COM decreased linearly. Within gradual treatments, HS and GS occurred at CO2 concentrations between 0.43 and 1.14%, LOP between 11.1 and 17.5%, while CRB and COM occurred between 61.8 and 78.4%. Overall, immersion induced distress, insensibility, and death significantly faster and with the shortest interval between distress and insensibility. For gradual treatment, insensibility and death occurred faster with increasing displacement rates. Behavioral signs of distress were observed with all treatments, and occurred at concentrations lower than those causing insensibility. In conclusion, immersion into 100% CO2 environment resulted in the shortest time of distress and fastest time to death compared to gradual displacement rates of any speed measured.

Transversus abdominis plane block with liposomal bupivacaine for pain control after cesarean delivery: a retrospective chart review.

BACKGROUND: Adverse effects of opioid analgesics and potential for chronic use are limitations in the cesarean setting. Regional anesthesia using transversus abdominis plane (TAP) block post-cesarean delivery may improve analgesia and reduce opioid consumption. Effectiveness of TAP block using liposomal bupivacaine (LB) to reduce post-cesarean pain is unknown. METHODS: We performed a single-center retrospective chart review of patients aged ≥18 years who underwent cesarean delivery with a multimodal pain management protocol with or without TAP block with LB 266 mg. Assessments included postsurgical opioid consumption; area under the curve (AUC) of numeric rating scale pain scores from 0 to 3 days; proportion of opioid-free patients; discharge- and post-anesthesia care unit (PACU)-ready time; times to ambulation, solid food, and bowel movement; hospital length of stay (LOS); and adverse events (AEs). Data were analyzed in the total population and in first- and repeat-cesarean subgroups using Wilcoxon, chi-squared, and Student's t-tests. RESULTS: Of 201 patients, 101 were treated with LB TAP block (LB-TAPB) and 100 without LB-TAPB. Treatment with LB-TAPB vs without LB-TAPB significantly reduced mean post-surgical opioid consumption (total, 47%; first-cesarean, 54%; repeat-cesarean, 42%; P<0.001 each) and mean AUC of pain scores (total, 46%; first-cesarean, 57%; repeat-cesarean, 40%; P<0.001 each). Patients treated with LB-TAPB had significantly shorter mean discharge-ready times (2.9 vs 3.6 days; P=0.006), PACU-ready times (138 vs 163 minutes; P=0.028), and LOS (2.9 vs 3.9 days; P<0.001). LB-TAPB significantly decreased mean times to ambulation and solid food by 39% and 31% (P<0.01 each), respectively, and numerically reduced mean time to bowel movement (26%; P=0.05). Fewer patients treated with LB-TAPB vs without LB-TAPB reported an AE (34% vs 50%; P=0.026). CONCLUSION: These results suggest multimodal pain management incorporating TAP block with LB 266 mg is an effective approach to reducing opioid requirements and improving analgesia post-cesarean delivery.

Generation and characterization of thiol-deficient Mycobacterium tuberculosis mutants.

Mycothiol (MSH) and ergothioneine (ERG) are thiols able to compensate for each other to protect mycobacteria against oxidative stress. Gamma-glutamylcysteine (GGC), another thiol and an intermediate in ERG biosynthesis has detoxification abilities. Five enzymes are involved in ERG biosynthesis, namely EgtA, EgtB, EgtC, EgtD and EgtE. The role of these enzymes in the production of ERG had been unclear. On the other hand, the enzyme MshA is known to be essential for MSH biosynthesis. In this manuscript, we describe the raw data of the generation and characterization of Mycobacterium tuberculosis (M.tb) mutants harbouring a deletion of the gene coding for each of these enzymes, and the raw data of the phenotypic characterization of the obtained thiol-deficient M.tb mutants. High throughput screening (HTS) of off-patent drugs and natural compounds revealed few compounds that displayed a higher activity against the thiol-deficient mutants relative to the wild-type strain. The mode of action of these drugs was further investigated. Raw data displaying these results are described here.

Frey's syndrome following a facial burn treated with botulinum toxin.

Frey's syndrome occurs as a result of damage to the auriculotemporal nerve, which causes inappropriate regeneration of damaged parasympathetic fibres to salivary glands to innervate the sympathetic receptors of sweat glands in the face. The symptoms are pathological flushing and sweating with gustatory stimuli. It most commonly occurs following parotid surgery and has not previously been reported following burn injury. We present a 50-year-old man who sustained 1% TBSA full thickness burn to the right side of his face as a child. This was excised and reconstructed with skin grafts as well as further revision procedures in his adult life. He incidentally reported copious amounts of gustatory sweating over his right temple region that had been present since his initial injury, occurring prior to any reconstruction, consistent with Frey's syndrome. This was confirmed with a starch iodine test, and successfully treated with Botulinum toxin injections post reconstruction. This case is the first report of Frey's syndrome following burn injury. We highlight the potential development of Frey's syndrome following facial burns, even in the reconstructed area. Botulinum toxin treatment remains effective.

Le syndrome de Frey est le résultat d'une lésion du nerf auriculo- temporal. C'est la régénération aberrante, au cours de leur trajet vers les glandes salivaires, des fibres parasympathiques endommagées innervant les récepteurs sympathiques des glandes sudoripares de la face, qui en est responsable. Les symptômes sont une rougeur pathologique et une hypersudation lors de stimulations gustatives. Il apparaît plus généralement lors de la chirurgie parotidienne et n'a jamais été rapporté après une brûlure. Nous rapportons l'observation d'un homme de 50 ans qui avait présenté dans l'enfance une brûlure profonde du côté droit du visage (surface 1 %). Cette brûlure avait été excisée et réparée par des greffes cutanées, et suivie de plusieurs retouches chirurgicales à l'âge adulte. Il décrivait, la survenue, lors de stimulations gustatives, d'importants phénomènes de sudation, au niveau de sa région temporale droite, et ce depuis le traumatisme initial et avant toute réparation réalisant un syndrome de Frey. Ceci fut confirmé par un test à l'iode-amidon et fut traité par des injections de toxine botulique après la reconstruction. Ce cas est le premier report d'un syndrome de Frey après une brûlure. Nous soulignons le développement possible d'un syndrome de Frey à la suite d'une brulure de la face, évoluant même après sa réparation. La toxine botulique reste une thérapeutique efficace.

The functional interplay of low molecular weight thiols in Mycobacterium tuberculosis.

BACKGROUND: Three low molecular weight thiols are synthesized by Mycobacterium tuberculosis (M.tb), namely ergothioneine (ERG), mycothiol (MSH) and gamma-glutamylcysteine (GGC). They are able to counteract reactive oxygen species (ROS) and/or reactive nitrogen species (RNS). In addition, the production of ERG is elevated in the MSH-deficient M.tb mutant, while the production of MSH is elevated in the ERG-deficient mutants. Furthermore, the production of GGC is elevated in the MSH-deficient mutant and the ERG-deficient mutants. The propensity of one thiol to be elevated in the absence of the other prompted further investigations into their interplay in M.tb. METHODS: To achieve that, we generated two M.tb mutants that are unable to produce ERG nor MSH but are able to produce a moderate (ΔegtD-mshA) or significantly high (ΔegtB-mshA) amount of GGC relative to the wild-type strain. In addition, we generated an M.tb mutant that is unable to produce GGC nor MSH but is able to produce a significantly low level of ERG (ΔegtA-mshA) relative to the wild-type strain. The susceptibilities of these mutants to various in vitro and ex vivo stress conditions were investigated and compared. RESULTS: The ΔegtA-mshA mutant was the most susceptible to cellular stress relative to its parent single mutant strains (ΔegtA and ∆mshA) and the other double mutants. In addition, it displayed a growth-defect in vitro, in mouse and human macrophages suggesting; that the complete inhibition of ERG, MSH and GGC biosynthesis is deleterious for the growth of M.tb. CONCLUSIONS: This study indicates that ERG, MSH and GGC are able to compensate for each other to maximize the protection and ensure the fitness of M.tb. This study therefore suggests that the most effective strategy to target thiol biosynthesis for anti-tuberculosis drug development would be the simultaneous inhibition of the biosynthesis of ERG, MSH and GGC.

Proteomic analysis reveals that sulfamethoxazole induces oxidative stress in M. tuberculosis.

The emerging resistance of tuberculosis (TB) to current first line drugs (isoniazid, rifampicin, pyrazinamide, ethambutol) warrants alternative treatment approaches with broad-spectrum efficacy. Previously, we have shown that sulfamethoxazole (SMX) has synergestic activity with rifampicin against Mycobacterium tuberculosis. The primary target of SMX is folP1 in mycobacteria; however, SMX may affect other secondary targets in M. tuberculosis. This study investigated the potential additional targets of SMX in a clinical isolate of M. tuberculosis using Orbitrap mass spectrometry to identify differentially expressed proteins following treatment with a sub-lethal concentration of SMX. Raw data have been deposited as ProteomeXchange accession PXD009315. Our proteomic analysis identified approximately 1500 proteins in total of which 45 proteins were differentially regulated as a result of SMX treatment. These included 25 upregulated and 20 downregulated proteins. The oxidative stress proteins (Rv2428, AhpC and Rv2394, GgtB) and an enzyme from the electron transport chain (Ndh-II, Rv1854c) were found to be upregulated. Gene expression analysis correlated with the observed proteomic changes. In conclusion our results show that SMX treatment of a drug sensitive M. tuberculosis clinical isolate resulted in the regulation of proteins involved in the oxidative stress response, indicating the induction of oxidative stress by SMX in mycobacteria.

Realization of a Λ System with Metastable States of a Capacitively Shunted Fluxonium.

We realize a Λ system in a superconducting circuit, with metastable states exhibiting lifetimes up to 8 ms. We exponentially suppress the tunneling matrix elements involved in spontaneous energy relaxation by creating a "heavy" fluxonium, realized by adding a capacitive shunt to the original circuit design. The device allows for both cavity-assisted and direct fluorescent readouts, as well as state preparation schemes akin to optical pumping. Since direct transitions between the metastable states are strongly suppressed, we utilize Raman transitions for coherent manipulation of the states.