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For marine cetaceans, Hg biomagnification can negatively affect neurological, hepatic, renal, and immune functions. To evaluate the use of biomarkers for Hg in dolphins, multiple tissues were analyzed from 127 stranded common bottlenose dolphins (Tursiops truncatus) from the estuarine and oceanic waters of Virginia, USA. Twenty-two percent of liver Hg concentrations exceeded the published observed effect level for liver abnormalities, and 26 % of cerebrum samples exceeded the published threshold for neurochemical changes, suggesting that Hg may have impacted dolphin health. Mercury tissue levels were similar to or lower than those reported from other locations (liver range: 1.4-943 μg/g-dw). Significant correlations were found between tissue types, indicating that skin or liver can be used as a biomarker to estimate the total Hg concentrations in the other tissue types (kidney, liver, cerebrum, cerebellum, pons). This is the first study to measure Hg concentrations in multiple brain regions of T. truncatus., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Background: Rumination is a cognitive process that has been implicated in the onset and maintenance of a variety of psychological difficulties. The purpose of this review and meta-analysis was to examine the nature and strength of the relationship between rumination and non-suicidal self-injury (NSSI)., Methods: The protocol for this review was pre-registered (CRD42019148186). A literature search of electronic databases PsycINFO, CINAHL, MEDLINE, and Web of Science was performed from the earliest date available to March 2020. Thirty-nine eligible papers were identified. An additional seven papers were identified from a search conducted in September 2021, resulting in a total of 46 papers. Separate meta-analyses were undertaken for NSSI frequency and NSSI history, with studies grouped by rumination type (depressive, transdiagnostic, anger, brooding, reflection, catastrophising, overall). Moderator analyses were also conducted along with a narrative synthesis of adjusted associations and longitudinal studies., Results: Rumination had a positive small association with NSSI frequency and a positive moderate association with NSSI history. The adjusted associations yielded mixed findings and most longitudinal research found rumination to be associated with prospective NSSI., Limitations: Most included studies had a moderate risk of bias and used a student sample. A limitation of this review was that only English language papers were included., Conclusions: Findings indicate that rumination is associated with NSSI, but more so the likelihood of engaging in NSSI overall than the frequency. Rumination-focused techniques for NSSI may therefore be of benefit. Further research is needed to understand this association, particularly with longitudinal studies that focus on state rumination rather than stable trait rumination., Practitioner Points: Rumination was found to have a small to moderate association with NSSI. Some individuals who engage in NSSI may benefit from psychological techniques that target rumination. Most of the studies included had a moderate risk of bias., (© 2021 The British Psychological Society.)

Background: Bisexual people are at an elevated risk for non-suicidal self-injury (NSSI). Psychological factors including self-esteem and thwarted belongingness may help explain this risk. The aim of the current study was to investigate associations between self-esteem, thwarted belongingness and NSSI urges and behavior in young bisexual people., Methods: Participants aged 16-25 from 25 countries took part in this microlongitudinal online survey study (N = 207). Mixed-effects linear and logistic regression were used for analysis, given the nested structure of data. Analysis examined the relationship between self-esteem and thwarted belongingness on NSSI urges and behavior at the same point in time, and lagged by one week., Results: At the same timepoint, self-esteem and thwarted belongingness both had significant between- and within-person associations with NSSI urges and behavior. For lagged models, self-esteem had significant between-person effects on urges, and thwarted belongingness had significant within-person effects. For NSSI behavior, both variables were only associated with between-person effects., Conclusion: Findings support previous research suggesting the importance of self-esteem in explaining NSSI among sexual minorities. Preventative and intervention strategies to improve self-esteem may help reduce NSSI risk. Future studies should focus upon the experiences of bisexual people with intersecting identities and ensure that studies are statistically powered from inception to detect effects., (© 2021 The Authors. Suicide and Life-Threatening Behavior published by Wiley Periodicals LLC on behalf of American Association of Suicidology.)

Background: Postoperative pain is a common clinical problem that, in preclinical studies, has almost exclusively been studied in males. Altered C-fibre activity-dependent slowing (ADS) is a potential underlying mechanism, given it is altered after tissue inflammation and nerve injury, but this has not been explored post-incision. We therefore investigated the effect of hind-paw incision on C-fibre ADS in both sexes and the involvement of voltage-gated sodium channels (Na V ) as they contribute to ADS. We also assessed mechanical and thermal sensitivity post-incision in both sexes., Methods: Dorsal roots were isolated from hind-paw incision (2-4 days post-surgery) or naive (control) juvenile rats of both sexes. Compound action potential recordings were made to assess C-fibre ADS in response to ×40 stimuli at 2 and 10 Hz and repeated in the presence of 20 nM tetrodotoxin/vehicle. Data were quantified by the normalised change in latency (negative peak) and width (positive-to-positive peak) of the triphasic C-fibre response. Hind-paw mechanical withdrawal thresholds and thermal withdrawal latencies were measured pre- and post-incision., Results: Incision facilitates C-fibre ADS in both sexes, with more pronounced facilitation in females. Tetrodotoxin induces sex- and injury-dependent changes in C-fibre ADS that were distinct between latency and width measures. Hind-paw incision induced comparable mechanical hypersensitivity in both sexes but less peak heat hypersensitivity in females., Conclusions: Hind-paw incision induces sex-dependent changes in C-fibre activity-dependent slowing, which likely contribute to the observed sex difference in peak thermal hypersensitivity. This may reflect sex- and incision-induced differences in functional expression of Na V channels that differs by C-fibre subtype., (Copyright © 2021 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.)

Background: 'Diabulimia' is the term given to the deliberate administration of insufficient insulin for the purpose of weight loss. Although Diabulimia can be life-threatening and prevalence rates in diabetes are high, there is a lack of research for how to effectively support people with the condition. This exploratory study aimed to provide much-needed information to healthcare professionals and guide the focus for future research., Methods: Forty-five individuals with Type 1 diabetes mellitus (T1DM) and a history of insulin misuse completed an online questionnaire. This included an assessment of their eating disorder psychopathology with the Eating Disorder Examination Questionnaire (EDE-Q) and 16 open-ended questions exploring their experience of Diabulimia. The responses to the open-ended questions were analysed using thematic analysis., Results: The average global EDE-Q score was 3.96 (1.21), which is consistent with eating disorder populations. Common themes identified were concerns about weight, difficulty coping with diabetes, past trauma, and the importance of relationships. Experiences with health professionals were overwhelmingly negative. Most participants had experienced serious medical intervention due to Diabulimia and were fully aware of the consequences of insulin restriction., Conclusions: Overall, individuals believed that a greater awareness of Diabulimia and more training for healthcare professionals is needed. While education on insulin misuse may be a necessary first step in treatment, psychological support is crucial. To deliver effective treatment, clinicians should be aware of the specific issues facing those with Diabulimia. The current study identified themes that clinicians may find useful to consider.

Within intertidal communities, aerial exposure (emergence during the tidal cycle) generates strong vertical zonation patterns with distinct growth boundaries regulated by physiological and external stressors. Forecasted accelerations in sea-level rise (SLR) will shift the position of these critical boundaries in ways we cannot yet fully predict, but landward migration will be impaired by coastal development, amplifying the importance of foundation species' ability to maintain their position relative to rising sea levels via vertical growth. Here we show the effects of emergence on vertical oyster-reef growth by determining the conditions at which intertidal reefs thrive and the sharp boundaries where reefs fail, which shift with changes in sea level. We found that oyster reef growth is unimodal relative to emergence, with greatest growth rates occurring between 20-40% exposure, and zero-growth boundaries at 10% and 55% exposures. Notably, along the lower growth boundary (10%), increased rates of SLR would outpace reef accretion, thereby reducing the depth range of substrate suitable for reef maintenance and formation, and exacerbating habitat loss along developed shorelines. Our results identify where, within intertidal areas, constructed or natural oyster reefs will persist and function best as green infrastructure to enhance coastal resiliency under conditions of accelerating SLR.

Two series of self-assembled monolayers (SAMs) of omega-substituted alkanethiolates on gold were used to systematically examine the effects of varying substratum surface chemistry and energy on the attachment of two model organisms of interest to the study of marine biofouling, the bacterium Cobetia marina (formerly Halomonas marina) and zoospores of the alga Ulva linza (formerly Enteromorpha linza). SAMs were formed on gold-coated glass slides from solutions containing mixtures of methyl- and carboxylic acid-terminated alkanethiols and mixtures of methyl- and hydroxyl-terminated alkanethiols. C. marina attached in increasing numbers to SAMs with decreasing advancing water contact angles (theta(AW)), in accordance with equation-of-state models of colloidal attachment. Previous studies of Ulva zoospore attachment to a series of mixed methyl- and hydroxyl-terminated SAMs showed a similar correlation between substratum theta(AW) and zoospore attachment. When the hydrophilic component of the SAMs was changed to carboxylate, however, the profile of attachment of Ulva was significantly different, suggesting that a more complex model of interfacial energetics is required.

We investigated surface selection and adhesion of motile zoospores of a green, macrofouling alga (Enteromorpha) to self-assembled monolayers (SAMs) having a range of wettabilities. The SAMs were formed from alkyl thiols terminated with methyl (CH(3)) or hydroxyl (OH) groups or mixtures of CH(3)- and OH-terminated alkyl thiols and were characterized by measuring the advancing contact angles and by X-ray photoelectron spectroscopy. There was a positive correlation between the number of spores that attached to the SAMs and increasing contact angle (hydrophobicity). Moreover, the sizes of the spore groups (adjacent spores touching) were larger on the hydrophobic SAMs. Video microscopy of a patterned arrangement of SAMs showed that more zoospores were engaged in swimming and "searching" above the hydrophobic sectors than above the hydrophilic sectors, suggesting that the cells were able to "sense" that the hydrophobic surfaces were more favorable for settlement. The results are discussed in relation to the attachment of microorganisms to substrata having different wettabilities.

We have characterized the immunoglobulin A (IgA)-Fc-binding properties and beta-antigen expression of several strains of group B streptococci by using ultrastructural immunocytochemistry. Colloidal gold-labeled tracers were used with intact and sectioned bacteria in order to gain information regarding the location and distribution of cell surface and cytoplasmic IgA-Fc-binding molecules and beta antigen. Colloidal gold (5- or 15-nm particles) was conjugated to IgA to characterize IgA-binding properties and to IgG to test for IgG binding. Rabbit anti-beta antiserum was reacted with the bacteria and then with protein G labeled with 15-nm colloidal gold particles. A double-labeling technique was used for simultaneous localization of IgA-Fc- and anti-beta-antibody-binding properties on sectioned bacteria. The data corroborated previous results which indicated that (i) IgA-Fc-binding and IgA-Fc-nonbinding forms of beta antigen can be secreted by strains which do not express beta antigen on the cell surfaces (HG806, VC75); (ii) differences in levels of expression of beta antigen and/or IgA-Fc-binding proteins can be detected among various group B isolates; (iii) group B streptococci do not express human IgG-Fc-binding proteins; and (iv) not all forms of beta antigen are capable of binding human IgA.

We undertook a morphological and immunochemical comparison of purified outer membrane antigens from oral and nonoral isolates of Bacteroides asaccharolyticus. Electron micrographs of thin sections of whole bacteria revealed a compact, electron-dense capsule external to the outer membrane of oral strains. A loose, web-like material was noted on the surface of several nonoral strains that was distinct from the dense capsule seen on oral strains. Polyacrylamide gel electrophoresis showed distinct differences in the protein band pattern between oral and nonoral isolates; sugar composition was similar with a few exceptions. An indirect fluorescent-antibody test utilizing antiserum to a purified capsular antigen from a single oral strain cross-reacted with all of numerous oral and nonoral strains of B. asaccharolyticus, thereby demonstrating a shared antigen that is species specific for B. asaccharolyticus. However, antibodies to an oral strain-derived capsular antigen were detectable by enzyme immunoassay only in serum from rabbits immunized with oral strains. Thus, definite morphological and immunochemical differences were found between oral and nonoral isolates of B.asaccharolyticus.

Cores are large, rod-shaped structures that have been found almost exclusively in group D streptococci, measure 0.1 to 0.16 mum in diameter, and extend the width or length of cells. This study has shown that cores are produced in the cells at a reproducible point in early stationary growth after extensive mesosomal formation and after the pH has dropped below 6.5. When cells containing cores were introduced into a fresh medium with a pH above 6.5, the structures disappeared within 5 min. The structures were not found in young, logarithmically growing cells but formed in these cells upon autolysis or treatment with penicillin. Cores that were forming or disintegrating appeared to have a lamellar substructure. When chloramphenicol was added to the medium before the culture reached stationary phase, no cores were found in the cells. Cytochemical studies indicated that cores contain protein and are not composed of cell wall material or other polysaccharides that contain 1,2-glycol groups.

We have developed and quantitated a reproducible standardized granulomatous inflammatory reaction using divinyl copolymer beads. Approximately 10000 gas sterilized beads (43-53 micron in diameter) are injected into the tail veins of mice and embolize to the lungs where they evoke granuloma formation which is maximal at 48 h. The anti-inflammatory effects of both steroidal and nonsteroidal agents, namely, bacterial levan, hydrocortisone acetate, polyanetholsulfonate, indomethacin, acetylsalicylic acid, ellagic acid, and aminophylline were determined by comparing granuloma size in treated animals with those in untreated controls. Granulomas in paraffin sections were traced on the ground glass screen of a light microscope and the area of each granuloma measured with a digitizer-computer programmed to prepare histograms and merge data from replicate experiments. Of the agents tested, the greatest reductions in granuloma size occurred after treatment with bacterial levan (71%), hydrocortisone (70%), polyanetholsulfonate (58%), and indomethacin (55%).

Ischemia was produced in the inner cortex of the rat kidney by clamping the pedicle (artery, vein, and ureter) and severing collateral connections. After 30 minutes of ischemia, a slight aggregation of membrane-associated particles was observed in the freeze-fractured plasma membranes. The aggregation was progressive after 60 and 120 minutes of ischemia. These changes were reversible after 15 and 240 minutes of reflow of blood following 30 or 60 minutes of ischemia. The changes were irreversible after 120 minutes of ischemia. The cells were vacuolated after ischemic periods of 30 minutes or longer and after 120 minutes of ischemia the tissue was severely damaged and aggregation of membrane-associated particles was evident in the vacuolar membranes. No changes in the tissue or plasma membrane were observed after 5 or 20 minutes of ischemia.

Mutans streptococci (MS) representing eight different serotypes were tested for their ability to coaggregate in vitro with oral actinomyces and other streptococcal species. Of the mutans streptococci tested, only strains of S. cricetus (formerly S. mutans serotype a) displayed pronounced coaggregations and only with certain strains of actinomyces. S. cricetus coaggregated, by lactose nonreversible mechanisms, with serotype 4 Actinomyces naeslundii WVU963 and WVU924 and with serotype 2 Actinomyces odontolyticus WVU758. The first pair was disaggregated by protein denaturants (e.g., sodium dodecyl sulfate and urea) and EDTA. This coaggregation was inhibited when the streptococcal, but not the actinomyces, partner was pretreated with either heat or protease, suggesting the presence of a protein mediator on only the streptococcal cell surface. The S. cricetus-A. odontolyticus coaggregation appeared to involve protein components on each cell, as shown by the lack of coaggregation after pretreatment of either cell type with heat or proteases. This coaggregation was also reversed by sodium dodecyl sulfate and urea, as well as by sodium deoxycholate, but not by EDTA. The data indicate that different mechanisms may be involved in each of these coaggregations.

A method is described for the preparation of protoplasts of Streptococcus mutans BHT. The muralytic enzyme mutanolysin was prepared free of contaminating proteinases and shown to completely dissolve cell walls of this strain. Whole cells were converted to stabilizable protoplasts by using the enzyme in an isotonic medium containing 40% raffinose. Experiments using [3H]thymidine and [14C]leucine as cytoplasmic pool markers revealed only minimal (10%) leakage during a 1-h incubation. Examination by electron microscopy revealed the apparent absence of structural cell wall on the enlarged spherical bodies. Quantitative chemical analyses of membranes prepared by lysing protoplasts demonstrated only very small amounts of rhamnose and trace amounts of galactose. These sugars are the principal components of the BHT cell wall polysaccharide. Also, there were only small amounts of peptidoglycan components (e.g., N-acetylglucosamine) in the purified membranes obtained by this method.

The tridimensional ultrastructure of the inner cortex of rat kidney has been studied by observing freeze-fractured tissue in stereo. The complex structure of the tubules, fenestrated capillaries and glomeruli is more readily observed through the irregular fracturing of the tissue that occurs in this technique. The ultrastructure of the brush border and interdigitating membranes of the proximal tubules, the structure of the fenestrated endothelial membranes of the capillaries and the ribbon-like appearance of the filtration space between the foot processes of the glomeruli were especially well depicted in stereo images of freeze-fractured renal tissue.

Changes in the number and sizes of membrane-associated particles have been quantitated in the protoplasmic (P) and exoplasmic (E) fracture faces of the outer membrane of nuclei isolated from the inner cortex following renal ischemia and reflow in the rat. No changes were observed in the inner nuclear membrane. After 20-min ischemia, the number of particles in both fracture faces decreased. With reflow, the total number of particles decreased after both 20- and 60-min ischemia. The partition coefficient (Kp = CPF/CEF) increased from 10 to 11 and 17 at 20- and 60-min ischemia then fell below control values to a Kp of 7 after 120 min. After reflow, Kp steadily decreased except after 20-min ischemia followed by 240-min reflow when Kp began to rise. The sizes of particles were predominantly 60 A in the P face of control outer membranes but became larger after ischemia. After 20- and 60-min ischemia with reflow, the size distribution became more normal. The shifts in particle numbers and sizes seem to indicate modifications within the membrane resulting from ischemia.

Thirty strains of streptococci were tested for lysis with lysozyme, and 29 of these could be lysed by the following method: (i) suspension of the cells to a Klett reading of 200 units (no. 42 filter) in 0.01 m tris(hydroxymethyl)aminomethane buffer, pH 8.2, after washing twice with the buffer; (ii) addition of lysozyme to a final concentration of 250 mug/ml with incubation for 60 min at 37 C; (iii) addition of sodium lauryl sulfate (SLS) to a final concentration of 0.2% and incubation up to an additional 15 min at 37 C. Significant lysis was obtained only after the addition of SLS. (Strains of groups A, E, and G were treated with trypsin at a concentration of 200 mug/ml for 2 hr at 37 C before exposure to lysozyme.) These parameters for optimal lysis of streptococci by lysozyme were established by testing the group D Streptococcus faecalis strain 31 which lyses readily with lysozyme and the group H strain Challis which is less susceptible to the action of the enzyme. Viability of S. faecalis decreased 96% after 3 min of exposure to 250 mug of lysozyme per ml, whereas the more resistant strain Challis retained 27% of the initial viability after the same period. After 60 min, there was almost total loss of viability in each case. Variations of three methods of lysing streptococci with lysozyme were compared with respect to the decrease in turbidity and the release of protein and deoxyribonucleic acid (DNA) effected by each variation. The method presented in this paper allowed the greatest release of these cytoplasmic constituents from S. faecalis and strain Challis. Transformation experiments using DNA obtained from strain Challis (streptomycinresistant) by this method showed that the DNA released is biologically active.