Does losing reduce the tendency to engage with rivals to reach mates? An experimental test.

Male-male contests for access to females or breeding resources are critical in determining male reproductive success. Larger males and those with more effective weaponry are more likely to win fights. However, even after controlling for such predictors of fighting ability, studies have reported a winner-loser effect: previous winners are more likely to win subsequent contests, while losers often suffer repeated defeats. While the effect of winning-losing is well-documented for the outcome of future fights, its effect on other behaviors (e.g. mating) remains poorly investigated. Here, we test whether a winning versus losing experience influenced subsequent behaviors of male mosquitofish (Gambusia holbrooki) toward rivals and potential mates. We housed focal males with either a smaller or larger opponent for 24 h to manipulate their fighting experience to become winners or losers, respectively. The focal males then underwent tests that required them to enter and swim through a narrow corridor to reach females, bypassing a cylinder that contained either a larger rival male (competitive scenario), a juvenile or was empty (non-competitive scenarios). The tests were repeated after 1 wk. Winners were more likely to leave the start area and to reach the females, but only when a larger rival was presented, indicating higher levels of risk-taking behavior in aggressive interactions. This winner-loser effect persisted for at least 1 wk. We suggest that male mosquitofish adjust their assessment of their own and/or their rival's fighting ability following contests in ways whose detection by researchers depends on the social context.

Psychological symptoms and health-related quality of life in intubated and non-intubated intensive care survivors: A multicentre, prospective observational cohort study.

Objective: To compare long-term psychological symptoms and health-related quality of life (HRQOL) in intubated versus non-intubated ICU survivors. Design: Prospective, multicentre observational cohort study. Setting: Four tertiary medical-surgical ICUs in Australia. Participants: Intubated and non-intubated adult ICU survivors. Main outcome measures: Primary outcomes: clinically significant psychological symptoms at 3- and 12-month follow-up using Post-Traumatic Stress Syndrome-14 for post-traumatic stress disorder; Depression, Anxiety Stress Scales-21 for depression, anxiety, and stress. Secondary outcomes: HRQOL, using EuroQol-5D-5L questionnaire. Results: Of the 133 ICU survivors, 54/116 (47 %) had at least one clinically significant psychological symptom (i.e., post-traumatic stress disorder, anxiety, depression, stress) at follow-up. Clinically significant scores for psychological symptoms were observed in 26 (39 %) versus 16 (32 %) at 3-months [odds ratio 1.4, 95 % confidence interval (0.66-3.13), p = 0.38]; 23 (37 %) versus 10 (31 %) at 12-months [odds ratio 1.3, 95 % confidence interval (0.53-3.31), p = 0.57] of intubated versus non-intubated survivors, respectively. Usual activities and mobility were the most commonly affected HRQOL dimension, with >30 % at 3 versus months and >20 % at 12-months of overall survivors reporting ≥ moderate problems. There was no difference between the groups in any of the EQ5D dimensions. Conclusions: Nearly one-in-two (47 %) of the intubated and non-intubated ICU survivors reported clinically significant psychological symptoms at 3 and 12-month follow-ups. Overall, more than 30 % at 3-months and over 20 % at 12-months of the survivors in both groups had moderate or worse problems with their usual activities and mobility. The presence of psychological symptoms and HRQOL impairments was similar between the groups.

Response to COVID-19 vaccination in patients on cancer therapy: Analysis in a SARS-CoV-2-naïve population.

BACKGROUND: Cancer patients have increased morbidity and mortality from COVID-19, but may respond poorly to vaccination. The Evaluation of COVID-19 Vaccination Efficacy and Rare Events in Solid Tumors (EVEREST) study, comparing seropositivity between cancer patients and healthy controls in a low SARS-CoV-2 community-transmission setting, allows determination of vaccine response with minimal interference from infection. METHODS: Solid tumor patients from The Canberra Hospital, Canberra, Australia, and healthy controls who received COVID-19 vaccination between March 2021 and January 2022 were included. Blood samples were collected at baseline, pre-second vaccine dose and at 1, 3 (primary endpoint), and 6 months post-second dose. SARS-CoV-2 anti-spike-RBD (S-RBD) and anti-nucleocapsid IgG antibodies were measured. RESULTS: Ninety-six solid tumor patients and 20 healthy controls were enrolled, with median age 62 years, and 60% were female. Participants received either AZD1222 (65%) or BNT162b2 (35%) COVID-19 vaccines. Seropositivity 3 months post vaccination was 87% (76/87) in patients and 100% (20/20) in controls (p = .12). Seropositivity was observed in 84% of patients on chemotherapy, 80% on immunotherapy, and 96% on targeted therapy (differences not satistically significant). Seropositivity in cancer patients increased from 40% (6/15) after first dose, to 95% (35/37) 1 month after second dose, then dropped to 87% (76/87) 3 months after second dose. CONCLUSION: Most patients and all controls became seropositive after two vaccine doses. Antibody concentrations and seropositivity showed a decrease between 1 and 3 months post vaccination, highlighting need for booster vaccinations. SARS-CoV-2 infection amplifies S-RBD antibody responses; however, cannot be adequately identified using nucleocapsid serology. This underlines the value of our COVID-naïve population in studying vaccine immunogenicity.

Lack of affinity signature for germinal center cells that have initiated plasma cell differentiation.

Long-lived plasma cells (PCs) secrete antibodies that can provide sustained immunity against infection. High-affinity cells are proposed to preferentially select into this compartment, potentiating the immune response. We used single-cell RNA-seq to track the germinal center (GC) development of Ighg2A10 B cells, specific for the Plasmodium falciparum circumsporozoite protein (PfCSP). Following immunization with Plasmodium sporozoites, we identified 3 populations of cells in the GC light zone (LZ). One LZ population expressed a gene signature associated with the initiation of PC differentiation and readily formed PCs in vitro. The estimated affinity of these pre-PC B cells was indistinguishable from that of LZ cells that remained in the GC. This remained true when high- or low-avidity recombinant PfCSP proteins were used as immunogens. These findings suggest that the initiation of PC development occurs via an affinity-independent process.

Plasticity in branch water relations and stem hydraulic vulnerability enhances hydraulic safety in mangroves growing along a salinity gradient.

Coping with water stress depends on maintaining cellular function and hydraulic conductance. Yet measurements of vulnerability to drought and salinity do not often focus on capacitance in branch organs that buffer hydraulic function during water stress. The relationships between branch water relations, stem hydraulic vulnerability and stem anatomy were investigated in two co-occurring mangroves Aegiceras corniculatum and Rhizophora stylosa growing at low and high salinity. The dynamics of branch water release acted to conserve water content in the stem at the expense of the foliage during extended drying. Hydraulic redistribution from the foliage to the stem increased stem relative water content by up to 21%. The water potentials at which 12% and 50% loss of stem hydraulic conductivity occurred decreased by ~1.7 MPa in both species between low and high salinity sites. These coordinated tissue adjustments increased hydraulic safety despite declining turgor safety margins at higher salinity sites. Our results highlight the complex interplay of plasticity in organ-level water relations with hydraulic vulnerability in the maintenance of stem hydraulic function in mangroves distributed along salinity gradients. These results emphasise the importance of combining water relations and hydraulic vulnerability parameters to understand vulnerability to water stress across the whole plant.

Early T Cell Infiltration Correlates with Anti-CTLA4 Treatment Response in Murine Cancer Models.

Immune checkpoint inhibitor (ICI) Abs are a revolutionary class of cancer treatment, but only ∼30% of patients receive a lasting benefit from therapy. Preclinical studies using animals from the same genetic backgrounds, challenged with the same cancer models, also show nonuniform responses. Most mouse studies that have evaluated tumor-infiltrating leukocytes after ICI therapy cannot directly correlate their findings with treatment outcomes, because terminal methods were used to acquire immune infiltrate data. In the present study, we used fine-needle aspiration (a nonterminal sampling method) to collect multiple aspirates over several days from s.c. implanted P815, CT26, and 4T1 mouse cancer models treated with ICI Abs. These aspirates were then analyzed with flow cytometry to directly correlate tumor-infiltrating leukocyte populations with treatment success. We found that the P815 and CT26 models respond well to anti-CTLA4 therapies. Among P815-challenged animals, mice that regressed following anti-CTLA4 treatment showed significant increases in CD8+ T cells on days 3, 5, and 7 and in CD4+ T cells on days 5 and 7 and a decrease in macrophages and monocytes on days 3, 5, and 7 after treatment. Similar results were obtained in the CT26 model on day 11 posttreatment. Our study is the first, to our knowledge, to directly correlate early tumor infiltration of T cells with anti-CTLA4 treatment success, thus providing a mechanistic clue toward understanding why alloidentical mice challenged with identical tumors do not respond uniformly to ICI therapies.

Ghosts of dry seasons past: Legacy of severe drought enhances mangrove salinity tolerance through coordinated cellular osmotic and elastic adjustments.

The incidence and severity of global mangrove mortality due to drought is increasing. Yet, little is understood of the capacity of mangroves to show long-term acclimation of leaf water relations to severe drought. We tested for differences between mid-dry season leaf water relations in two cooccurring mangroves, Aegiceras corniculatum and Rhizophora stylosa before a severe drought (a heatwave combined with low rainfall) and after its relief by the wet season. Consistent with ecological stress memory, the legacy of severe drought enhanced salinity tolerance in the subsequent dry season through coordinated adjustments that reduced the leaf water potential at the turgor loss point and increased cell wall rigidity. These adjustments enabled maintenance of turgor and relative water content with increasing salinity. As most canopy growth occurs during the wet season, acclimation to the 'memory' of higher salinity in the previous dry season enables greater leaf function with minimal adjustments, as long-lived leaves progress from wet through dry seasons. However, declining turgor safety margins - the difference between soil water potential and leaf water potential at turgor loss - implied increasing limitation to water use with increasing salinity. Thus, plasticity in leaf water relations contributes fundamentally to mangrove function under varying salinity regimes.

New insights from modelling studies and molecular dynamics simulations of the DIS5-S6 extracellular linker of the skeletal muscle sodium channel NaV1.4.

In the CryoEM-structure of the hSkMNaV1.4 ion channel (PDB:6AGF), the 59-residue DIS5-S6 linker peptide was omitted due to absence of electron density. This peptide is intriguing - comprised of unique sequence and found only in mammalian skeletal muscle sodium ion channels. To probe potential physiological and evolutionary significance, we constructed an homology model of the complete hSkMNaV1.4 channel. Rather than a flexible random coil potentiating drift across the channel, the linker folds into a compact configuration through self-assembling secondary structural elements. Analogous sequences from 48 mammalian organisms show hypervariability with between 40% and 100% sequence similarity. To investigate structural implications, sequences from 14 representative organisms were additionally modelled. All showed highly conserved N-and C-terminal residues closely superimposed, suggesting a critical functional role. An optimally located asparagine residue within the conserved region was investigated for N-linked glycosylation and MD simulations carried out. Results suggest a complex glycan added at this site in the linker may form electrostatic interactions with the DIV voltage sensing domain and be mechanistically involved in channel gating. The relationship of unique sequence, compact configuration, potential glycosylation and MD simulations are discussed relative to SkMNaV1.4 structure and function.

The Effect of Scale Insects on Growth Parameters of cv. Chardonnay and cv. Sauvignon Blanc Grapevines Grown in a Greenhouse.

Plants can respond to insects that feed with stylet mouthparts using various processes that are initiated via the salicylic acid metabolic pathway. In Australia, scale insects of the genus Parthenolecanium can cause economic damage to grapevines as they feed on the vines and produce honeydew as a waste by-product, which supports the growth of black sooty mould on fruit and leaves, potentially affecting the plant growth and yield. Using rootlings of Sauvignon Blanc (SB, resistant) and Chardonnay (Char, susceptible), the growth and production of volatile organic compounds (VOCs) following exposure to scale insect infestations were measured under controlled greenhouse conditions. At harvest, the numbers of scale insects per five leaves were higher on plants infested at the start of the study compared with the control plants. Infested SB had increased dry root and shoot mass compared with the SB control, which was also the case with Char (control and infested). Leaf volatiles differed between cultivars in response to scale infestation. Benzyl alcohol decreased among infested SB plants compared with the other treatments. A change in the salicylic acid pathway as indicated by the change in benzyl alcohol may cause the increased growth in SB associated with the increased scale insect infestation.

Compression Therapy Is Cost-Saving in the Prevention of Lower Limb Recurrent Cellulitis in Patients with Chronic Edema.

Background: Cellulitis is a common and often recurrent infection that causes substantial financial burden and morbidity. Compression therapy reduces the risk of recurrent cellulitis episodes for adults with chronic edema; however, little is known about the cost-effectiveness of the intervention. Methods and Results: A cost analysis was undertaken during a randomized controlled trial (RCT) involving 84 participants with lower limb chronic edema and a history of recurrent cellulitis. The intervention group received compression therapy and education, while the control group received education only. A clinical audit and survey were used to measure health service and patient resource use for (1) the most recent episode of cellulitis, and (2) compression therapy over 18 months. Australian reference costs were used to calculate cellulitis and compression therapy costs, and the mean expenditure in both the RCT groups. Of the 84 RCT participants, 43 were surveyed and audited on the cost of cellulitis, and 40 on the cost of compression therapy. The mean cost of a hospitalized and nonhospitalized episode of cellulitis was $9071 and $506 from a health service perspective, and $4496 and $1320 from a patient perspective. The mean cost of compression therapy per participant over 18 months was $1905 and $421 from health service and patient perspectives, respectively. During the RCT, the mean annual cost per participant was $4972 in the experimental group and $26,382 in the control group, giving a cost-saving of $21,483 (95% confidence interval, 3136-48,176) per participant. Conclusion: For patients with lower limb chronic edema and recurrent cellulitis, compression therapy is both efficacious and cost-saving. Trial Registration: ACTRN12617000412336.

Does mechanical threshold inspiratory muscle training promote recovery and improve outcomes in patients who are ventilator-dependent in the intensive care unit? The IMPROVE randomised trial.

BACKGROUND: In patients who are ventilator-dependent in the intensive care unit, inspiratory muscle training may improve inspiratory muscle strength and accelerate liberation from the ventilator, but optimal training parameters are yet to be established, and little is known about the impact of inspiratory muscle training on quality of life or dyspnoea. Thus, we sought to ascertain whether inspiratory muscle training, commenced while ventilator-dependent, would improve outcomes for patients invasively ventilated for 7 days or longer. METHODS: In this randomised trial with assessor blinding and intention-to-treat analysis, 70 participants (mechanically ventilated ≥7 days) were randomised to receive once-daily supervised high-intensity inspiratory muscle training with a mechanical threshold device in addition to usual care or to receive usual care (control). Primary outcomes were inspiratory muscle strength (maximum inspiratory pressure % predicted) and endurance (fatigue resistance index) at ventilator liberation and 1 week later. Secondary outcomes included quality of life (SF-36v2, EQ-5D), dyspnoea, physical function, duration of ventilation, and in-hospital mortality. RESULTS: Thirty-three participants were randomly allocated to the training group, and 37 to the control group. There were no statistically significant differences in strength (maximum inspiratory pressure) (95% confidence interval [CI]: -7.4 to 14.0) or endurance (fatigue resistance index) (95% CI: -0.003 to 0.436). Quality of life improved significantly more in the training group than in the control group (EQ-5D: 17.2; 95% CI: 1.3-33.0) (SF-36-PCS: 6.97; 95% CI: 1.96-12.00). Only the training group demonstrated significant reductions in dyspnoea (-1.5 at rest, -1.9 during exercise). There were no between-group differences in duration of ventilation or other measures. In-hospital mortality was higher in the control group than in the training group (9 vs 4, 24% vs 12%, p = 0.23). CONCLUSIONS: In patients who are ventilator-dependent, mechanical threshold loading inspiratory muscle training improves quality of life and dyspnoea, even in the absence of strength improvements or acceleration of ventilator liberation.

Comprehensive systematic review and pooled analysis of real-world studies evaluating immunomodulator and biologic therapies for chronic pouchitis treatment.

Background and Aim: Pouchitis is a common complication after restorative ileal pouch-anal anastomosis following proctocolectomy for ulcerative colitis. Antibiotic-dependent or antibiotic-refractory chronic pouchitis (CP), which is a common cause of pouch failure affecting 15-20% of patients, is challenging to treat. The efficacy of second-line immunomodulator and biologic therapy remains poorly defined. We present a pooled analysis of real-world efficacy data from peer-reviewed full-text manuscripts, focusing on immunomodulator and biologic therapies in CP. Methods: Embase and PubMed databases were searched for full-text articles describing the treatment of CP. We performed a systematic review and pooled analysis of published studies to assess the efficacy of immunomodulators, including thiopurines and methotrexate, and biologics including antitumor necrosis factor, anti-integrin, and interleukin-12/23 antagonists. Clinical and endoscopic response and remission rates were combined for pooled analyses. Rates of treatment discontinuation and safety were also assessed. Results: Pooled analysis comprised 20 full-text articles (485 patients). Overall clinical response rate was 46% (95% CI: 35-59%) and clinical remission rate was 35% (95% CI: 21-52%). Overall endoscopic response and remission rates were 41% (95% CI: 18-68%) and 15% (95% CI: 5-39%), respectively. Individual agents' safety profile was reassuring, with vedolizumab being the most favorable. Conclusion: The real-world efficacy data of immunomodulators in the treatment of CP is insufficient. Vedolizumab and ustekinumab appeared effective and safe for CP, whereas anti-TNFs showed higher rates of adverse events. The high heterogeneity within the studies is attributed to the real-world study design, obfuscating drug efficacy comparisons across the studies. Further studies are required to define the comparative effectiveness of available treatments of CP.

Arthroscopic Femoral and Acetabular Osteoplasties Alter the In Vivo Hip Kinematics of Patients With Femoroacetabular Impingement.

Purpose: Three-dimensional (3D)-two-dimensional (2D) fluoroscopic image registration was used to measure 3D hip kinematics before and after hip arthroscopy in patients with femoroacetabular impingement (FAI). Methods: In total, 24 subjects diagnosed with FAI (21 unilateral, 3 bilateral) were prospectively recruited. A clinical impingement test was performed on both hips while the patient was awake and then while anaesthetized, and in the operative hip after arthroscopic osteoplasties and labral repair. Fluoroscopy was used to image the hip during the impingement tests. Images were analyzed using 3D-2D image registration to calculate joint kinematics. The examiner's hand was instrumented with a glove to measure internal rotation torque applied to the hip during each test. Results: Internal rotation increased by 3.7° (standard error [SE] 0.95°) after surgery (P = .001). Maximum displacement of the femoral head out of the acetabulum was 4.0 mm (SE 0.5 mm) in the operative group before surgery and 1.8 mm (SE 0.3 mm) after surgery (P < .001). This was due to a decrease in lateral displacement by 1.3 mm (SE 0.4 mm, P = .002) and proximal displacement by 0.8 mm (SE 0.3 mm, P = .013). Internal rotation torque was greater in the operative hips when anaesthetized compared with when awake, by 5 Nm (SE 1.2 Nm, P < .001), and greater in the contralateral hips than the operative hips when awake by 8.4 Nm (SE 1.4 mm, P < .001). Conclusions: Arthroscopic osteoplasty and labral repair increased hip range of motion and reduced femoral head displacement from the acetabulum during the IR90 provocation test (i.e., hip flexion to 90°, maximum internal rotation) in patients with FAI. This suggests that the impinging acetabular rim acted as a fulcrum before surgery and may have caused edge loading that was reduced after surgery. Level of Evidence: Level IV case series, therapeutic study.

Gut microbiome-depleting antibiotic regimens are not tolerated by all mouse strains: learn from (our) bitter experience.

Why the gut microbiome is critical for the success of checkpoint inhibitor cancer therapy is a question that remains unanswered, but progress has slowed. We argue that this lack of advancement is due to an unappreciated biological detail. Here, we show that the antibiotic cocktail used in seminal publications-all of which have used the C57BL/6 mouse strain-are bitter and not tolerated by other common mouse strains (ie, BALB/c and DBA/2). We write to alert readers of this important biological limitation that must be considered when planning cancer experiments investigating the gut microbiota, to prevent the unnecessary dehydration of experimental animals, and to save our colleagues valuable experimental time and resources.

Serious cycling-related fractures in on and off-road accidents: A retrospective analysis in the Australian Capital Territory region.

Cycling is an increasingly popular activity which is widely supported by health advocates. In the last year, more than a third of Australians used a bike [1]. While road cycling remains popular, participation in off-road recreational cycling, including mountain biking, bicycle moto cross (BMX) riding, and outdoor leisure cycling, is increasing and this is associated with an increase in the number and cost of cycling injuries [2-5]. The aim of this study was to describe and compare contemporary patterns of cycling fracture requiring hospitalisation as a function of cycling mode in the Australian Capital Territory region. This retrospective analysis of cycling-related-fracture hospitalisations in the ACT region described data recorded between July 2012 and December 2019. Logistic regression models were used to calculate probabilities of sustaining a fracture at different sites for each of the cycling modes (on-road, mountain, BMX, leisure, unspecified). These likelihoods were then compared against the on-road fracture profile. Cycling-related-fracture hospitalisations increased by 32% in the seven years analysed. Of all fracture admissions, 442 (33%) were on-road, 658 (49%) off-road, and 242 (18%) unknown. The majority were male (79%), median age 37 (IQR 16, 52). Median length of stay was two days. The number of fractures per admission ranged from one to thirteen with a median of one. Wrist, clavicle, ribs, and skull were the four most frequent fracture sites for all cycling modes. Fracture profiles of on- and off-road accidents were similar, with the exception of wrist fractures which were more likely in off-road (OR 1.96, p < 0.01) and unspecified cycling accidents (OR 5.07, p < 0.01). Skull fractures comprised 19% of all BMX-related fractures. More than half of all fracture-related admissions required surgery. With increasing support for sustainable and healthy transport and recreation activities, the fracture profiles of different cycling modes must first be assessed in order to inform strategies to reduce and manage this injury burden.

Communicating Endometriosis Pain in France and Australia: An Interview Study.

Endometriosis is characterized by persistent, fluctuating pain associated with menstruation, a biological function which is socially invisible. The degree and quality of pain cannot easily be measured, observed, or documented. Difficulties in communicating pain pose particular challenges when seeking diagnosis and support from health professionals. In this paper we explore the experiences and characterization of pain by thirteen Australian and thirteen French women with endometriosis. Data were collected through semi-structured interviews using a life-history approach to illness symptoms, diagnosis and treatment. We explore the experiences of women with endometriosis in two phases: from onset of symptoms to seeking advice from a clinician, and from first consulting a clinician to receiving a diagnosis. On average, initial pain symptoms were identified 2.1 years before consulting a health practitioner, after which women reported pain symptoms 8.5 years prior to diagnosis; that is, the time between consulting a clinician and receiving a diagnosis was almost four times the period between experiencing symptoms and consulting a doctor. Pain was often "made real" to doctors by findings consistent with endometriosis on ultrasound and MRI, mostly used in France, or laparoscopy, the predominant diagnostic tool in Australia. No woman described her practitioner using standardized pain assessment tools. Thus, the validation of pain relies largely on disease visibility and the clinician-classified degree of severity rather than self-reported grades of pain or impact on activities of daily living. The invisible and enigmatic pain of this chronic women's disease remains difficult to communicate to doctors, and the recognition of severe pain is often key to timely diagnostic procedures. Clinicians need to be more proactive about severe pain related to menstruation, taking into consideration women's individual circumstances, and maintain a high index of suspicion of underlying endometriosis as a condition characterized primarily by pain.

Profiling Urinary Sulfate Metabolites With Mass Spectrometry.

The study of urinary phase II sulfate metabolites is central to understanding the role and fate of endogenous and exogenous compounds in biological systems. This study describes a new workflow for the untargeted metabolic profiling of sulfated metabolites in a urine matrix. Analysis was performed using ultra-high-performance liquid chromatography-high resolution tandem mass spectrometry (UHPLC-HRMS/MS) with data dependent acquisition (DDA) coupled to an automated script-based data processing pipeline and differential metabolite level analysis. Sulfates were identified through k-means clustering analysis of sulfate ester derived MS/MS fragmentation intensities. The utility of the method was highlighted in two applications. Firstly, the urinary metabolome of a thoroughbred horse was examined before and after administration of the anabolic androgenic steroid (AAS) testosterone propionate. The analysis detected elevated levels of ten sulfated steroid metabolites, three of which were identified and confirmed by comparison with synthesised reference materials. This included 5α-androstane-3ß,17α-diol 3-sulfate, a previously unreported equine metabolite of testosterone propionate. Secondly, the hydrolytic activity of four sulfatase enzymes on pooled human urine was examined. This revealed that Pseudomonas aeruginosa arylsulfatases (PaS) enzymes possessed higher selectivity for the hydrolysis of sulfated metabolites than the commercially available Helix pomatia arylsulfatase (HpS). This novel method provides a rapid tool for the systematic, untargeted metabolic profiling of sulfated metabolites in a urinary matrix.

Real-Time Analysis of Mitochondrial Electron Transport Chain Function in Toxoplasma gondii Parasites Using a Seahorse XFe96 Extracellular Flux Analyzer.

The mitochondrial electron transport chain (ETC) performs several critical biological functions, including maintaining mitochondrial membrane potential, serving as an electron sink for important metabolic pathways, and contributing to the generation of ATP via oxidative phosphorylation. The ETC is important for the survival of many eukaryotic organisms, including intracellular parasites such as the apicomplexan Toxoplasma gondii. The ETC of T. gondii and related parasites differs in several ways from the ETC of the mammalian host cells they infect, and can be targeted by anti-parasitic drugs, including the clinically used compound atovaquone. To characterize the function of novel ETC proteins found in the parasite and to identify new ETC inhibitors, a scalable assay that assesses both ETC function and non-mitochondrial parasite metabolism (e.g., glycolysis) is desirable. Here, we describe methods to measure the oxygen consumption rate (OCR) of intact T. gondii parasites and thereby assess ETC function, while simultaneously measuring the extracellular acidification rate (ECAR) as a measure of general parasite metabolism, using a Seahorse XFe96 extracellular flux analyzer. We also describe a method to pinpoint the location of ETC defects and/or the targets of inhibitors, using permeabilized T. gondii parasites. We have successfully used these methods to investigate the function of T. gondii proteins, including the apicomplexan parasite-specific protein subunit TgQCR11 of the coenzyme Q:cytochrome c oxidoreductase complex (ETC Complex III). We note that these methods are also amenable to screening compound libraries to identify candidate ETC inhibitors.

The Role of DNA Methylation in Genome Defense in Cnidaria and Other Invertebrates.

Considerable attention has recently been focused on the potential involvement of DNA methylation in regulating gene expression in cnidarians. Much of this work has been centered on corals, in the context of changes in methylation perhaps facilitating adaptation to higher seawater temperatures and other stressful conditions. Although first proposed more than 30 years ago, the possibility that DNA methylation systems function in protecting animal genomes against the harmful effects of transposon activity has largely been ignored since that time. Here, we show that transposons are specifically targeted by the DNA methylation system in cnidarians, and that the youngest transposons (i.e., those most likely to be active) are most highly methylated. Transposons in longer and highly active genes were preferentially methylated and, as transposons aged, methylation levels declined, reducing the potentially harmful side effects of CpG methylation. In Cnidaria and a range of other invertebrates, correlation between the overall extent of methylation and transposon content was strongly supported. Present transposon burden is the dominant factor in determining overall level of genomic methylation in a range of animals that diverged in or before the early Cambrian, suggesting that genome defense represents the ancestral role of CpG methylation.

Simple and effective bacterial-based intratumoral cancer immunotherapy.

BACKGROUND: We describe intratumoral injection of a slow-release emulsion of killed mycobacteria (complete Freund's adjuvant (CFA)) in three preclinical species and in human cancer patients. METHODS: Efficacy and safety were tested in mammary tumors in mice, in mastocytomas in mice and dogs, and in equine melanomas. In mice, survival, tumor growth, and tumor infiltration by six immune cell subsets (by flow cytometry) were investigated and analyzed using Cox proportional hazards, a random slopes model, and a full factorial model, respectively. Tumor growth and histology were investigated in dogs and horses, as well as survival and tumor immunohistochemistry in dogs. Tumor biopsies were taken from human cancer patients on day 5 (all patients) and day 28 (some patients) of treatment and analyzed by histology. CT scans are provided from one patient. RESULTS: Significantly extended survival was observed in mouse P815 and 4T1 tumor models. Complete tumor regressions were observed in all three non-human species (6/186 (3%) of mouse mastocytomas; 3/14 (21%) of canine mastocytomas and 2/11 (18%) of equine melanomas). Evidence of systemic immune responses (regression of non-injected metastases) was also observed. Analysis of immune cells infiltrating mastocytoma tumors in mice showed that early neutrophil infiltration was predictive of treatment benefit. Analysis of the site of mastocytoma regression in dogs weeks or months after treatment demonstrated increased B and T cell infiltrates. Thus, activation of the innate immune system alone may be sufficient for regression of some injected tumors, followed by activation of the acquired immune system which can mediate regression of non-injected metastases. Finally, we report on the use of CFA in 12 human cancer patients. Treatment was well tolerated. CT scans showing tumor regression in a patient with late-stage renal cancer are provided. CONCLUSION: Our data demonstrate that intratumoral injection of CFA has major antitumor effects in a proportion of treated animals and is safe for use in human cancer patients. Further trials in human cancer patients are therefore warranted. Our novel treatment provides a simple and inexpensive cancer immunotherapy, immediately applicable to a wide range of solid tumors, and is suitable to patients in developing countries and advanced care settings.