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Burns and other traumatic injuries represent a substantial biomedical burden. The current standard of care for deep injuries is autologous split-thickness skin grafting (STSG), which frequently results in contractures, abnormal pigmentation, and loss of biomechanical function. Currently, there are no effective therapies that can prevent fibrosis and contracture after STSG. Here, we have developed a clinically relevant porcine model of STSG and comprehensively characterized porcine cell populations involved in healing with single-cell resolution. We identified an up-regulation of proinflammatory and mechanotransduction signaling pathways in standard STSGs. Blocking mechanotransduction with a small-molecule focal adhesion kinase (FAK) inhibitor promoted healing, reduced contracture, mitigated scar formation, restored collagen architecture, and ultimately improved graft biomechanical properties. Acute mechanotransduction blockade up-regulated myeloid CXCL10-mediated anti-inflammation with decreased CXCL14-mediated myeloid and fibroblast recruitment. At later time points, mechanical signaling shifted fibroblasts toward profibrotic differentiation fates, and disruption of mechanotransduction modulated mesenchymal fibroblast differentiation states to block those responses, instead driving fibroblasts toward proregenerative, adipogenic states similar to unwounded skin. We then confirmed these two diverging fibroblast transcriptional trajectories in human skin, human scar, and a three-dimensional organotypic model of human skin. Together, pharmacological blockade of mechanotransduction markedly improved large animal healing after STSG by promoting both early, anti-inflammatory and late, regenerative transcriptional programs, resulting in healed tissue similar to unwounded skin. FAK inhibition could therefore supplement the current standard of care for traumatic and burn injuries.

Objective: Mandibular distraction osteogenesis (MDO) is frequently performed to address airway obstruction in patients with Pierre Robin sequence (PRS), though more recently the technique of orthodontic airway plating (OAP) has gained traction. We aimed to evaluate OAP compared to MDO for airway obstruction in PRS., Design: A systematic literature search across PubMed, Embase, and Google Scholar identified all studies published in English, which involved MDO or any form of OAP as treatments for PRS. All relevant articles were reviewed in detail and reported on, adhering to PRISMA guidelines., Main Outcome Measures: Airway (tracheostomy avoidance, decannulation rate), feeding (full oral feeding tolerance)., Results: Literature search identified 970 articles, of which 42 MDO studies and 9 OAP studies met criteria for review. A total of 1159 individuals were treated with MDO, and 322 individuals were treated with OAP. Primary outcomes appear similar for MDO and OAP at face value; however, this must be interpreted with different pretreatment contexts in mind., Conclusions: Orthodontic airway plating may be considered for airway obstruction in PRS, as some airway-related and feeding-related outcomes appear similar with MDO, per existing evidence in the literature. However, since PRS severity differed between studies, OAP cannot be uniformly considered a replacement for MDO. Further research is required to more comprehensively assess these treatment modalities inclusive of metrics that allow for direct comparison.

This study was designed to promote enhanced self-efficacy and decreased stress levels for family caregivers at a hospice care hospital, thus increasing their quality of life. This is achieved through group flower arranging sessions. The objectives are to (a) enhance self-efficacy scores for family caregivers of Calvary patients, (b) decrease stress levels for family caregivers of Calvary patients, and (c) disseminate results to other hospices. The results show that the flower arranging sessions resulted in significantly increased self-efficacy and decreased stress and associated problems for the caregiver participants. Implications and suggestions for future research are discussed.

Abstract: The primary organ systems and tissues concerning plastic and reconstructive surgery include the integument, vasculature, subcutis, and peripheral nerves, because these may individually or collectively be injured requiring reconstruction, or indeed be used in reconstruction themselves through grafts, flaps, or anastomoses. Adrenergic receptors are present throughout these anatomic components on the vasculature, adipose, platelets, immune cells, keratinocytes, melanocytes, fibroblasts, peripheral nerves, and tendons. Herein, the influence of adrenergic signaling on the physiology of anatomic components related to plastic surgery is discussed, along with clinical considerations of this systems involvement in procedures, such as free flap reconstruction, skin grafting, fat grafting, and other areas relevant to plastic and reconstructive surgery. Current evidence as well as potential for further investigation is discussed., Competing Interests: Conflicts of interest statement and sources of funding: none declared., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Since 1950, the portion size of many snack foods has more than doubled and obesity rates have tripled. Portion size determines energy intake, often unwittingly., Purpose: This paper tests whether salient visual cues to portion size on the packaging of high fat, sugar, or salty (HFSS) snacks can reduce consumption., Methods: Two preregistered randomized controlled trials (N = 253 and N = 674) measured consumption in a lab and the home environment. Cues were salient, labeled stripes that demarcated single portions. Participants were randomized to cue condition or control. Consumption was measured without awareness., Results: The main preregistered effect of the visual cue was not statistically significant. There was some variation by subgroup. In Study 1, men were more likely to eat the whole can of potato chips than women but significantly reduced consumption when visual cues were on the pack. The effect size was large: the number of men eating more than the recommended portion fell by 33%. Study 2 monitored household consumption of chocolate biscuits (cookies) sent to family homes in gift packs. Again, the main effect was nonsignificant but there was significant subgroup variation. When the person receiving the biscuits was female, households were more likely to eat more than the recommended portion per person per day, but less likely when the visual cues were displayed. The gender of the eaters was not known. The effect size was again large: the number of households eating more than the recommended portion fell by 26%. Households with children were also less likely to open packs with visual cues compared to control packs. Both studies recorded significant increases in the likelihood of observing serving size information, together with confusion about what it means., Conclusions: The studies offer some evidence that salient visual cues could play a role in tackling the high consumption of unhealthy snacks, but the effects are confined to specific subgroups and warrant further investigation., (© Society of Behavioral Medicine 2020. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: Self-isolation is a vital element of efforts to contain COVID-19. We set out to test whether decision aids can support self-isolation., Design: We conducted a pre-registered online experiment with a nationally representative sample (n = 500). Three stages tested: (i) whether decision trees help people to decide whether they need to self-isolate; (ii) whether an online planning tool increases people's confidence in their ability to self-isolate; and (iii) whether infographics help people to absorb advice on managing a household in which someone must self-isolate., Main Outcome Measures: (i) Accuracy of matching symptom patterns to a response scale for the need to self-isolate; (ii) self-reported confidence in coping with self-isolation; (iii) objective tests of recall and comprehension., Results: Decision trees improved decisions about when self-isolation was necessary, although participants systematically underestimated the need to self-isolate with less common COVID-19 symptoms (e.g. sore throat, fatigue). The online planning tool increased confidence about coping with self-isolation only among the adults aged under 40. Infographics improved recall and comprehension of how to manage self-isolation., Conclusion: Decision aids can be used to support self-isolation during COVID-19. The study also demonstrates how even an emergency public health response can benefit from rapid experimental pre-testing of interventions.

Despite the lack of guidelines regarding the use of intra-arterial lines in postmastectomy breast reconstruction (PMBR), they continue to be used in this setting. In this study of patients undergoing PMBR, we aimed to (1) identify factors associated with intra-arterial line placement, (2) analyze the correlation between intra-arterial monitoring and noninvasive blood pressure (NIBP) monitoring, and (3) investigate whether hemodynamic management differs significantly between patients undergoing intra-arterial blood pressure monitoring versus NIBP., Methods: All patients undergoing flap-based PMBR between 2017 and 2019 were retrospectively reviewed. Patients were pair-matched based on flap donor site, BMI, and age to identify factors associated with intra-arterial line placement. Methods described by Bland and Altman 1 were utilized to determine agreement between intra-arterial line measurements and NIBP., Results: Thirty-two patients were included with 16 patients in the intra-arterial line group and 16 in the NIBP group. None of the factors studied were significantly related to the likelihood of intra-arterial line placement. Agreement analysis demonstrated that mean arterial pressures calculated from intra-arterial line readings were as much as 23 points lower or 12 points higher than those from NIBP. Bias calculations with this extent of difference suggest poor correlation between intra-arterial line readings and NIBP. There was no difference between groups in rate of administration of blood-pressure altering medications (hypertensive: n = 3, 18.8%, P = 1.000; hypotensive: n = 7, 3.8%, P = 1.000)., Conclusion: Our findings highlight the need for more definitive guidance regarding the use of intra-arterial monitoring in patients undergoing PMBR., (Copyright © 2021 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of The American Society of Plastic Surgeons.)

Rationale: Maintaining social distance during the COVID-19 pandemic can save lives. We therefore set out to test communication strategies to promote social distancing., Objective: We aimed to test two novel public health messages against a control message. The first was designed to exploit the "identifiable victim" effect by highlighting the risk of transmission to identifiable vulnerable persons. The second sought to counteract intuitive underestimation of exponential transmission., Method: In total, 500 Irish adults undertook a pre-registered, online experiment. They were randomly assigned to a control group or one of two treatment groups. The control group viewed a current poster that encouraged a 2-m separation between people. The two treatment groups saw posters of similar design, but with narrative messages describing how an individual had infected a specific vulnerable person or multiple other people. Later questions measured intentions to undertake three specific types of social interaction over the coming days and the stated acceptability of three other types of social interaction. Pilot work had identified these six behaviors as "marginal" - people were unsure whether they were advisable., Results: Participants in the treatment conditions were more cautious about undertaking the behaviors and less accepting of them. This positive effect occurred despite participants rating the treatment posters as likely to be less effective and memorable than the control poster., Conclusions: Messages that invoke thoughts of infecting vulnerable people or large numbers of people can motivate social distancing and, hence, help to limit the spread of COVID-19. Stated public evaluations (obtained via focus groups or surveys) may underestimate the actual effectiveness of such emotional messages., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Attention Deficit Hyperactivity Disorder (ADHD) is a common neuropsychiatric disorder in which children present prefrontal cortex (PFC) related functions deficit. Proactive cognitive control is a process that anticipates the requirement of cognitive control and crucially depends on the maturity of the PFC. Since this process is important to ADHD symptomatology, we here test the hypothesis that children with ADHD have proactive cognitive control impairments and that these impairments are reflected in the PFC oscillatory activity. We recorded EEG signals from 29 male children with ADHD and 25 typically developing (TD) male children while they performed a Go-Nogo task, where the likelihood of a Nogo stimulus increased while a sequence of consecutive Go stimuli elapsed. TD children showed proactive cognitive control by increasing their reaction time (RT) concerning the number of preceding Go stimuli, whereas children with ADHD did not. This adaptation was related to modulations in both P3a potential and lateral prefrontal theta oscillation for TD children. Children with ADHD as a group did not demonstrate either P3a or theta modulation. But, individual variation in theta activity was correlated with the ADHD symptomatology. The results depict a neurobiological mechanism of proactive cognitive control impairments in children with ADHD., (Copyright © 2020 Zamorano, Kausel, Albornoz, Lavin, Figueroa-Vargas, Stecher, Aragón-Caqueo, Carrasco, Aboitiz and Billeke.)

Introduction: Cosmetic breast surgery is commonly performed in the United States; 520,000 procedures of the total 1.8 million cosmetic surgical procedures performed in 2018 were breast related. Postoperative chronic pain, defined as lasting 3 or more months, has been reported in a wide variety of breast surgical procedures including breast augmentation, reduction mammaplasty, mastectomy, and mastectomy with reconstruction. Patient characteristics associated with the development of postoperative chronic pain following cosmetic breast surgery include a younger age, larger BMI, smaller height, postoperative hyperesthesia, and elevated baseline depression, anxiety, and catastrophizing scores. The anatomical distribution of chronic pain following breast augmentation procedures is dependent upon incision site placement; pectoral and intercostal nerves have been implicated. The purpose of this review is to provide an update on the current literature addressing the pathophysiology, clinical presentation, and treatment of patients presenting with chronic postoperative pain following cosmetic breast surgery., Methods: A comprehensive literature review was performed in MEDLINE, PubMed, and Cochrane databases from 1996 to 2019 using the terms "cosmetic surgery", "breast surgery", "postoperative pain", and "chronic pain"., Results: Cosmetic breast surgery can have a similar presentation as post-mastectomy pain syndrome and thus have overlapping diagnostic criteria. Seven domains are identified for a diagnosis of PBSPS: Pain after breast surgery, neuropathic in nature, at least a moderate intensity of pain, as defined as within the middle one-third of the selected pain scale, pain for at least 6 months, symptoms occurring for 12 or more hours a day for a minimum of 4 days each week, pain in at least one of the following sites: breast, chest wall, axilla, or arm on the affected side, pain exacerbated by movement. Patient risk factors and surgical risk factors may influence the development of chronic post-cosmetic surgery breast pain. Improved perioperative analgesia including preoperative regional nerve anesthesia and postoperative catheter infusion have been shown to improve chronic postoperative pain outcomes., Conclusions: The present review provides a discussion of clinical presentation, pathophysiology, and treatment and preventative strategies for chronic breast pain following cosmetic surgery. This review provides evidence from multiple randomized controlled trials (RCTs) and systematic reviews of efficacy and effectiveness. While chronic postoperative breast pain remains challenging to treat, various preventative strategies have been described to improve postoperative pain outcomes.

Current measures for assessing the viability of donor kidneys are lacking. Optical coherence tomography (OCT) can image subsurface tissue morphology to supplement current measures and potentially improve prediction of post-transplant function. OCT imaging was performed on donor kidneys before and immediately after implantation during 169 human kidney transplant surgeries. A system for automated image analysis was developed to measure structural parameters of the kidney's proximal convoluted tubules (PCTs) visualized in the OCT images. The association of these structural parameters with post-transplant function was investigated. This study included kidneys from live and deceased donors. 88 deceased donor kidneys in this study were stored by static cold storage (SCS) and an additional 15 were preserved by hypothermic machine perfusion (HMP). A subset of both SCS and HMP deceased donor kidneys were classified as expanded criteria donor (ECD) kidneys, with elevated risk of poor post-transplant function. Post-transplant function was characterized as either immediate graft function (IGF) or delayed graft function (DGF). In ECD kidneys stored by SCS, increased PCT lumen diameter was found to predict DGF both prior to implantation and following reperfusion. In SCD kidneys preserved by HMP, reduced distance between adjacent lumen following reperfusion was found to predict DGF. Results suggest that OCT measurements may be useful for predicting post-transplant function in ECD kidneys and kidneys stored by HMP. OCT analysis of donor kidneys may aid in allocation of kidneys to expand the donor pool as well as help predict post-transplant function in transplanted kidneys to inform post-operative care., Competing Interests: Drs. Chen and Tang have financial interests in Vitae Organi, Inc., which, however, did not provide support for this work. Drs. Chen and Andrews hold a U.S. patent “Apparatus and Methods for Non-invasive Assessment of Transplant Kidney Viability” (US 9,737,256 B2). Other authors declare that there are no conflicts of interest related to this article.

Recent theories of decision making propose a shared value-related brain mechanism for encoding monetary and social rewards. We tested this model in children with Attention-Deficit/Hyperactivity Disorder (ADHD), children with Autism Spectrum Disorder (ASD) and control children. We monitored participants' brain dynamics using high density-electroencephalography while they played a monetary and social reward tasks. Control children exhibited a feedback Error-Related Negativity (fERN) modulation and Anterior Cingulate Cortex (ACC) source activation during both tasks. Remarkably, although cooperation resulted in greater losses for the participants, the betrayal options generated greater fERN responses. ADHD subjects exhibited an absence of fERN modulation and reduced ACC activation during both tasks. ASD subjects exhibited normal fERN modulation during monetary choices and inverted fERN/ACC responses in social options than did controls. These results suggest that in neurotypicals, monetary losses and observed disloyal social decisions induced similar activity in the brain value system. In ADHD children, difficulties in reward processing affected early brain signatures of monetary and social decisions. Conversely, ASD children showed intact neural markers of value-related monetary mechanisms, but no brain modulation by prosociality in the social task. These results offer insight into the typical and atypical developments of neural correlates of monetary and social reward processing.

Purpose of Review: Teen pregnancy has been subject of public concern for many years. In the United States, despite nearly 2 decades of declining teen pregnancy and birth rates, the problem persists, with significant disparities present across racial groups and in state-specific rates. This review examines recent trends, pregnancy prevention initiatives and family planning policies that address the special needs of vulnerable youth., Recent Findings: Unintended teen pregnancies impose potentially serious social and health burdens on teen parents and their children, as well as costs to society. Trends in teen pregnancy and birth rates show continued decline, but state and racial disparities have widened. Demographic factors and policy changes have contributed to these disparities. Research supports comprehensive pregnancy prevention initiatives that are multifaceted and promote consistent and correct use of effective methods of contraception for youth at risk of becoming pregnant., Summary: There is strong consensus that effective teen pregnancy prevention strategies should be multifaceted, focusing on delay of sexual activity especially in younger teens while promoting consistent and correct use of effective methods of contraception for those youth who are or plan to be sexually active. There is a need for further research to identify effective interventions for vulnerable populations.

Objective: To look at (1) the association between antipsychotics and cell stress, (2) whether first-generation antipsychotics may show different effects than second-generation antipsychotics, and (3) whether recommendations can be made regarding medication., Data Sources: We conducted a systematic review of 5 databases for all articles published until December 31, 2007: PubMed, Ovid MEDLINE, EMBASE, PsycINFO, and EBM Reviews. Under specific headings (eg, "heat shock proteins" and "oxidative stress"), a systematic search of these databases included such terms as HSP70 and homocysteine, and specific search strings were constructed. No limits were placed on the year or language of publication. References from pertinent articles or books were retrieved., Study Selection: We included 42 articles of human studies from 2,387 references originally retrieved. We included only articles that (1) were quantitative; (2) referred only to human tissue, in vivo, or in vitro; (3) stated what tissue was examined; (4) identified what metabolites were measured; and (5) had references., Data Extraction: All articles were assessed by 2 authors, which ensured that the inclusion criteria were met. The selected studies were too heterogeneous to be combined for any useful meta-analysis. Three authors, therefore, independently interpreted the data, using specified criteria to judge whether each study showed a beneficial, detrimental, or no effect on the markers measured., Data Synthesis: The analysis revealed no conclusive association with direct or indirect markers of oxidative cell stress and antipsychotics. For every reviewed antipsychotic, we revealed differing research results showing a beneficial, detrimental, or no effect. This was true for in vivo as well as in vitro studies., Conclusions: It remains unclear whether antipsychotics increase or reduce cell stress. Claims of neuroprotective properties of antipsychotics seem premature., (© Copyright 2011 Physicians Postgraduate Press, Inc.)

Heat shock proteins have been shown to be secreted from a number of cell types. Necrotic cells release heat shock proteins in a passive manner, whereas we, and others, have shown that viable cells secrete Hsp70 and Hsp60 through an active mechanism involving lysosomal vesicles and lipid rafts. This release of Hsp70 and Hsp60 is regulated, for example by being increased by elevated temperature. This article outlines procedures, using Hsp70 as the example, to: ensure the status of cells (viable, apoptotic or necrotic); identify the heat shock protein secreted; and quantify the secreted protein. Hsp70 has previously been quantified by ELISA, but newer methods are now being adopted, such as BIAcore and bead-based assays for use by FACS. These methods have the advantages of being more sensitive and requiring less sample than ELISA. The BIAcore has the potential to analyse Hsp70 ligands and provide affinity constants. The FACS bead assay system can be used to run multiplex assays.

Abstract It has been suggested that induction of the heat shock response in the mammalian embryo during the critical period of organogenesis can result in anatomical malformation. We measured serum heat shock protein 70 (Hsp70), anti-Hsp70, and anti-Hsp60 in samples taken from expectant mothers at 16 weeks gestation. Samples from women whose babies were born with a birth defect (n = 30) were compared with controls who gave birth to healthy babies (n = 46). Anti-Hsp70 levels were significantly elevated in patients who later gave birth to babies with cleft lip or palate or neurological abnormalities (n = 10): 260 (223-406) microg/mL compared to 150 (88-207) microg/mL in controls (P < 0.001). No significant differences were found in serum Hsp70 and anti-Hsp60 levels between cases and controls. This finding of increased maternal anti-Hsp70 in patients who later gave birth to babies with these abnormalities suggests a previous stressful event may have contributed to the pathogenesis. Further work is required to determine whether Hsp70 has a direct or indirect role in this pathogenesis or whether anti-Hsp70 is simply a marker of a prior increase in Hsp70 due to a physiological stress that itself resulted in the damage. This work is consistent with previous studies showing a buffering role for Hsps in evolution.

Purpose of Review: This review analyzes the most relevant studies on current surgical strategies to treat glaucoma patients with cataracts., Recent Findings: No clear evidence has confirmed better results with trabeculectomy alone compared with phacotrabeculectomy. Recent studies have reported successful outcomes combining deep sclerectomy and two-site phacoemulsification. The phacoemulsification cataract extraction will not vary the intraocular pressure of patients with previous deep sclerectomy. Mitomycin C proved to be effective in maintaining lower pressure levels with the combined surgery technique; however, 5-fluorouracil did not show any improvement. Minimally invasive cataract surgery reduces surgical trauma, making it possible to obtain better results with combined surgery and previous glaucoma surgery., Summary: The surgical strategy decision must be customized to every patient. Only filtering surgeries are recommended in glaucoma patients with incipient cataract. Combined surgical procedures are recommended for progressive or advanced glaucoma. Two-site phacotrabeculectomy with mitomycin C achieves better stabilized results; however, combined phacoemulsification with deep sclerectomy or viscocanalostomy achieves similar results with a lower rate of complications. These promising findings need more study to be confirmed.

Type 2 diabetes patients are subject to oxidative stress as a result of hyperglycemia. The aim of this study was to determine whether administration of the antioxidant folic acid, previously shown to reduce homocysteine levels, would reduce circulating levels of Hsp70 while improving the condition of type 2 diabetes patients with microalbuminuria. Plasma homocysteine fell from pretreatment values of 12.9 to 10.3 microM (P < 0.0001). The urine albumin-creatinine ratio fell from 12.4 to 10.4 mg/mM (P = 0.38). Pretreatment Hsp70 levels were higher in patients not taking insulin (5.32 ng/mL) compared with those on insulin (2.44 ng/mL) (P = 0.012). Folic acid supplementation resulted in a significant fall in Hsp70 (5.32 to 2.05 ng/mL) (P = 0.004). There was no change in Hsp70 in those receiving insulin. Folic acid supplementation in non-insulin-treated type 2 diabetes patients, therefore, resulted in a fall in Hsp70, reflecting an improvement in oxidative stress. The data shows that improvement in homocysteine status can lead to a reduction in Hsp70, indicating the possibility of its use as a marker for severity of disease.

There are an increasing number of studies reporting the presence of Hsps in human serum. We have investigated the release of Hsp70 into blood and culture medium from peripheral blood mononuclear cells (PBMCs), and whether this release is due to cell damage or active secretion from the cells. Intact Hsp70 was released from cells within whole blood and from purified PBMCs under normal culture conditions. Hsp70 release was rapid (0.1 ng/10(6) cells/h) over the first 2 h of culture and continued at a reduced rate up to 24 h (<0.025 ng/10(6) cells/h). Using viable cell counts and lactate dehydrogenase release we were able to confirm that the release of Hsp70 was not due to cellular damage. Hsp70 release was inhibited by monensin, methyl-beta-cyclodextrin, and methylamine, but not by brefeldin A. These data suggest that Hsp70 is released from cells via a non-classical pathway, possibly involving lysosomal lipid rafts.

Vertical excitation energies of the Rydberg radical NH4 are inferred from ab initio electron propagator calculations on the electron affinities of NH4+. The adiabatic ionization energy of NH4 is evaluated with coupled-cluster calculations. These predictions provide optimal parameters for the molecular-adapted quantum defect orbital method, which is used to determine Einstein emission coefficients and radiative lifetimes. Comparisons with spectroscopic data and previous calculations are discussed., (Copyright 2004 American Institute of Physics)

Chaperonins are protein complexes that are believed to function as part of a protein folding system in the cytoplasm of the cell. We observed, however, that the group II chaperonins known as rosettasomes in the hyperthermophilic archaeon Sulfolobus shibatae, are not cytoplasmic but membrane associated. This association was observed in cultures grown at 60 degrees C and 76 degrees C or heat-shocked at 85 degrees C by using immunofluorescence microscopy and in thick sections of rapidly frozen cells grown at 76 degrees C by using immunogold electron microscopy. We observed that increased abundance of rosettasomes after heat shock correlated with decreased membrane permeability at lethal temperature (92 degrees C). This change in permeability was not seen in cells heat-shocked in the presence of the amino acid analogue azetidine 2-carboxylic acid, indicating functional protein synthesis influences permeability. Azetidine experiments also indicated that observed heat-induced changes in lipid composition in S. shibatae could not account for changes in membrane permeability. Rosettasomes purified from cultures grown at 60 degrees C and 76 degrees C or heat-shocked at 85 degrees C bind to liposomes made from either the bipolar tetraether lipids of Sulfolobus or a variety of artificial lipid mixtures. The presence of rosettasomes did not significantly change the transition temperature of liposomes, as indicated by differential scanning calorimetry, or the proton permeability of liposomes, as indicated by pyranine fluorescence. We propose that these group II chaperonins function as a structural element in the natural membrane based on their intracellular location, the correlation between their functional abundance and membrane permeability, and their potential distribution on the membrane surface.

Violet-blue light is toxic to mammalian cells, and this toxicity has been linked with cellular production of H2O2. In this report, we show that violet-blue light, as well as UVA, stimulated H2O2 production in cultured mouse, monkey, and human cells. We found that H2O2 originated in peroxisomes and mitochondria, and it was enhanced in cells overexpressing flavin-containing oxidases. These results support the hypothesis that photoreduction of flavoproteins underlies light-induced production of H2O2 in cells. Because H2O2 and its metabolite, hydroxyl radicals, can cause cellular damage, these reactive oxygen species may contribute to pathologies associated with exposure to UVA, violet, and blue light. They may also contribute to phototoxicity often encountered during light microscopy. Because multiphoton excitation imaging with 1,047-nm wavelength prevented light-induced H2O2 production in cells, possibly by minimizing photoreduction of flavoproteins, this technique may be useful for decreasing phototoxicity during fluorescence microscopy.

In this report, the authors trace the development of an effective statewide tobacco control program following victory at the Massachusetts polls in 1992. They examine the pitfalls standing in the way of coalition building and present important lessons for states in similar positions.

The tobacco control leaders of four states that have successfully passed tobacco tax ballot initiatives (California, Massachusetts, Arizona, and Oregon) were brought together to this conference to discuss what happens after the passage of such an initiative, how to defend tobacco control funds against diversion for other purposes by a state's legislature, and how to use the revenues maximally to reduce the health and economic toll taken by tobacco use. At the conference, the attendees from each state presented reports that will undoubtedly be useful to other states seeking to pass their own tobacco tax legislation or initiatives.

The mechanism by which epithelial cells rearrange is a process that is central to epithelial morphogenesis, yet remains poorly understood. We have investigated epithelial cell rearrangement in the dorsal hypodermis of the Caenorhabditis elegans embryo, in which two rows of epithelial cells rearrange in a morphogenetic process known as dorsal intercalation. The intercalating cells extend basal protrusions which squeeze between their opposing neighbors beneath their adherens junctions. As the intercalating cells move forward, these protruding tips become broader in the anterior-posterior and dorsoventral dimensions, effectively "plowing through" the adherens junctions and forcing an opening for the remainder of the intercalating cell to insert between the contralateral cells. These cell movements are dependent upon intact cytoarchitecture, since the pharmacological disruption of microtubules or actin filaments blocks cell rearrangement. The cells appear to intercalate independently of immediately adjacent neighboring hypodermal cells because dorsal intercalation is not blocked by the ablation of the progenitors for either half of the lateral hypodermal cells or the posterior half of the dorsal hypodermis. This is the first case in which the protrusive mechanism underlying epithelial cell rearrangement has been characterized, and we propose a model describing how epithelial cells rearrange within the confines of an epithelial monolayer, and discuss the mechanisms that may be guiding these directed cell movements., (Copyright 1998 Academic Press.)

We have used transmission electron microscopy to examine plasmodesmata of the charophycean green alga Chara zeylanica, and of the putatively early divergent bryophytes Monoclea gottschei (liverwort), Notothylas orbicularis (hornwort), and Sphagnum fimbriatum (moss), in an attempt to learn when seed plant plasmodesmata may have originated. The three bryophytes examined have desmotubules. In addition, Monoclea was found to have branched plasmodesmata, and plasmodesmata of Sphagnum displayed densely staining regions around the neck region, as well as ring-like wall specializations. In Chara, longitudinal sections revealed endoplasmic reticulum (ER) that sometimes appeared to be associated with plasmodesmata, but this was rare, despite abundant ER at the cell periphery. Across all three fixation methods, cross-sectional views showed an internal central structure, which in some cases appeared to be connected to the plasma membrane via spoke-like structures. Plasmodesmata were present even in the incompletely formed reticulum of forming cell plates, from which we conclude that primary plasmodesmata are formed at cytokinesis in Chara zeylanica. Based on these results it appears that plasmodesmata of Chara may be less specialized than those of seed plants, and that complex plasmodesmata probably evolved in the ancestor of land plants before extant lineages of bryophytes diverged.

Because there is little available research, this study examined the associations between scores on the Wechsler Intelligence Scale for Children-Third Edition and the Woodcock-Johnson Tests of Achievement-Revised for 85 children with diagnosed emotional handicaps. Analysis indicated associations were significant.