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Neurochemicals corelease has received much attention in understanding brain activity and cognition. Despite many attempts, the multiplexed monitoring of coreleased neurochemicals with spatiotemporal precision and minimal crosstalk using existing methods remains challenging. Here, we report a soft neural probe for multiplexed neurochemical monitoring via electrografting-assisted site-selective functionalization of aptamers on graphene field-effect transistors (G-FETs). The neural probes possess excellent flexibility, ultralight mass (28 mg), and a nearly cellular-scale dimension of 50 μm × 50 μm for each G-FET. As a demonstration, we show that G-FETs with electrochemically grafted molecular linkers (-COOH or -NH(2)) and specific aptamers can be used to monitor serotonin and dopamine with high sensitivity (limit of detection: 10 pM) and selectivity (dopamine sensor > 22-fold over norepinephrine; serotonin sensor > 17-fold over dopamine). In addition, we demonstrate the feasibility of the simultaneous monitoring of dopamine and serotonin in a single neural probe with minimal crosstalk and interferences in phosphate-buffered saline, artificial cerebrospinal fluid, and harvested mouse brain tissues. The stability studies show that multiplexed neural probes maintain the capability for simultaneously monitoring dopamine and serotonin with minimal crosstalk after incubating in rat cerebrospinal fluid for 96 hours, though a reduced sensor response at high concentrations is observed. Ex vivo studies in harvested mice brains suggest the potential applications in monitoring the evoked release of dopamine and serotonin. The developed multiplexed detection methodology can also be adapted for monitoring other neurochemicals, such as amino acids and neuropeptides, by simply replacing the aptamers functionalized on the G-FETs.

We aimed to identify and describe the current interventions used in preoperative programs ("prehabilitation") for spine surgery. Knowledge gaps in approaches, feasibility, timing, patient experience, clinical outcomes, and health care costs were explored while describing their potential benefits on physical and psychological outcomes. An electronic search was conducted from January 2004 to February 2022 in Ovid Medline, Embase, EBSCO CINAHL, the Cochrane Database of Systematic Reviews, and PEDro to identify studies in English evaluating adults enrolled in prehabilitation before undergoing elective spine surgeries. Studies were uploaded into DistillerSR for systematic screening after removing duplicates. Four reviewers screened nested references for inclusion based on titles and abstracts, followed by their full-text review. Two reviewers subsequently extracted data and summarized the results. The results were reported using Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews guidelines. Studies were rated for quality using National Health and Medical Research Council criteria. Out of 18,879 potential studies, a total of 23 studies (0.12%) met the eligibility criteria and were included in this scoping review. The prehabilitation programs included general education (n = 6, 26%), exercise (n = 6, 26%), cognitive behavioral therapy (n = 3, 13%), pain neuroscience education (n = 3, 13%), health behavior counseling (n = 3, 13%), and mindfulness (n = 2, 9%). Additional studies are needed to identify optimal patient characteristics, intervention dosage, and whether multimodal approaches using a combination of physical and psychological strategies lead to more favorable outcomes. Although studies on prehabilitation for spine surgery are limited, they seem to demonstrate that prehabilitation programs are feasible, reduce medical expenditures, and improve patients' postoperative pain, disability, self-efficacy, psychological behaviors, and satisfaction with surgical outcomes. The available literature suggests there is an opportunity to improve patient experience, clinical outcomes and reduce medical costs with the use of prehabilitation in spine surgery.

As a member of the Back Pain Consortium (BACPAC), the University of Pittsburgh Mechanistic Research Center's research goal is to phenotype chronic low back pain using biological, biomechanical, and behavioral domains using a prospective, observational cohort study. Data will be collected from 1,000 participants with chronic low back pain according to BACPAC-wide harmonized and study-specific protocols. Participation lasts 12 months with one required in person baseline visit, an optional second in person visit for advanced biomechanical assessment, and electronic follow ups at months 1, 2, 3, 4, 5, 6, 9, and 12 to assess low back pain status and response to prescribed treatments. Behavioral data analysis includes a battery of patient-reported outcomes, social determinants of health, quantitative sensory testing, and physical activity. Biological data analysis includes omics generated from blood, saliva, and spine tissue. Biomechanical data analysis includes a physical examination, lumbopelvic kinematics, and intervertebral kinematics. The statistical analysis includes traditional unsupervised machine learning approaches to categorize participants into groups and determine the variables that differentiate patients. Additional analysis includes the creation of a series of decision rules based on baseline measures and treatment pathways as inputs to predict clinical outcomes. The characteristics identified will contribute to future studies to assist clinicians in designing a personalized, optimal treatment approach for each patient.

The Biobehavioral Working Group of BACPAC was charged to evaluate a range of psychosocial, psychophysical, and behavioral domains relevant to chronic low back pain, and recommend specific assessment tools and procedures to harmonize biobehavioral data collection across the consortium. Primary references and sources for measure selection were the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials, the Minimum Data Set from the NIH Research Task Force on Standards for Chronic Low Back Pain, the Patient-Reported Outcomes Measurement Information System, and NeuroQOL. The questionnaire recommendations supplemented the NIH HEAL Common Data Elements and BACPAC Minimum Data Set. Five domains were identified for inclusion: Pain Characteristics and Qualities; Pain-Related Psychosocial/Behavioral Factors; General Psychosocial Factors; Lifestyle Choices; and Social Determinants of Health/Social Factors. The Working Group identified best practices for required and optional Quantitative Sensory Testing of psychophysical pain processing for use in BACPAC projects.

The real-time monitoring of neurochemical release in vivo plays a critical role in understanding the biochemical process of the complex nervous system. Current technologies for such applications, including microdialysis and fast-scan cyclic voltammetry, suffer from limited spatiotemporal resolution or poor selectivity. Here, we report a soft implantable aptamer-graphene microtransistor probe for real-time monitoring of neurochemical release. As a demonstration, we show the monitoring of dopamine with nearly cellular-scale spatial resolution, high selectivity (dopamine sensor > 19-fold over norepinephrine), and picomolar sensitivity, simultaneously. Systematic benchtop evaluations, ex vivo experiments, and in vivo studies in mice models highlight the key features and demonstrate the capability of capturing the dopamine release dynamics evoked by pharmacological stimulation, suggesting the potential applications in basic neuroscience studies and studying neurological disease-related processes. The developed system can be easily adapted for monitoring other neurochemicals and drugs by simply replacing the aptamers functionalized on the graphene microtransistors.

Chronic low back pain (cLBP) is highly prevalent in the United States and globally, resulting in functional impairment and lowered quality of life. While many treatments are available for cLBP, clinicians have little information about which specific treatment(s) will work best for individual patients or subgroups of patients. The Back Pain Research Consortium, part of the National Institutes of Health Helping to End Addiction Long-termThe primary objective of this article is to provide an update on evidence-based cLBP interventions and describe the process of reviewing and selecting interventions for inclusion in the clinical trial.A working group of cLBP experts reviewed and selected interventions for inclusion in the clinical trial. The primary evaluation measures were strength of evidence and magnitude of treatment effect. When available in the literature, duration of effect, onset time, carryover effect, multimodal efficacy, responder subgroups, and evidence for the mechanism of treatment effect or biomarkers were considered.The working group selected 4 leading, evidence-based treatments for cLBP to be tested in the clinical trial and for use in routine clinical treatment. These treatments include (1) duloxetine, (2) acceptance and commitment therapy, (3) a classification-based exercise and manual therapy intervention, and (4) a self-management approach. These interventions each had a moderate to high level of evidence to support a therapeutic effect and were from different therapeutic classes.

Background In an article published in 2011, we discussed the need for a new role in health care systems, referred to as the Primary Spine Practitioner (PSP). The PSP model was proposed to help bring order to the chaotic nature of spine care. Over the past decade, several efforts have applied the concepts presented in that article. The purpose of the present article is to discuss the ongoing need for the PSP role in health care systems, present persistent barriers, report several examples of the model in action, and propose future strategies. Main body The management of spine related disorders, defined here as various disorders related to the spine that produce axial pain, radiculopathy and other related symptoms, has received significant international attention due to the high costs and relatively poor outcomes in spine care. The PSP model seeks to bring increased efficiency, effectiveness and value. The barriers to the implementation of this model have been significant, and responses to these barriers are discussed. Several examples of PSP integration are presented, including clinic systems in primary care and hospital environments, underserved areas around the world and a program designed to reduce surgical waiting lists. Future strategies are proposed for overcoming the continuing barriers to PSP implementation in health care systems more broadly. Conclusion Significant progress has been made toward integrating the PSP role into health care systems over the past 10 years. However, much work remains. This requires substantial effort on the part of those involved in the development and implementation of the PSP model, in addition to support from various stakeholders who will benefit from the proposed improvements in spine care.

The purpose of the study was to compare utilization and charges generated by medical doctors (MD), doctors of chiropractic (DC) and physical therapists (PT) by provider patterns of care for the treatment of neck pain in North Carolina.This was an analysis of neck-pain-related closed claim data from the North Carolina State Health Plan for Teachers and State Employees (NCSHP) from 2000 to 2009. Data were extracted from Blue Cross Blue Shield of North Carolina for the NCSHP using ICD-9 diagnostic codes for uncomplicated neck pain (UNP) and complicated neck pain (CNP).Care patterns with single-provider types and no referrals incurred the least average charges for both UNP and CNP. When care did not include referral providers or services, for either UNP or CNP, MD care with PT was generally less expensive than MD care with DC care. However, when care involved referral providers or services, MD and PT care was on average more expensive than MD and DC care for either UNP or CNP. Risk-adjusted charges for patients in the middle quintile of risk (available 2006-2009) were lower for chiropractic patients with or without medical care or referral care to other providers.Chiropractic care alone or DC with MD care incurred appreciably fewer charges for UNP or CNP compared to MD care with or without PT care, when care included referral providers or services. This finding was reversed when care did not include referral providers or services. Risk-adjusted charges for UNP and CNP patients were lower for DC care patterns.

The purpose of the study was to compare patterns of utilization and charges generated by medical doctors (MDs), doctors of chiropractic (DCs), and physical therapists (PTs) for the treatment of headache in North Carolina.Retrospective analysis of claims data from the North Carolina State Health Plan for Teachers and State Employees from 2000 to 2009. Data were extracted from Blue Cross Blue Shield of North Carolina for the North Carolina State Health Plan using International Classification of Diseases, Ninth Revision, diagnostic codes for headache. The claims were separated by individual provider type, combination of provider types, and referral patterns.The majority of patients and claims were in the MD-only or MD plus referral patterns. Chiropractic patterns represented less than 10% of patients. Care patterns with single-provider types and no referrals incurred the least charges on average for headache. When care did not include referral providers or services, MD with DC care was generally less expensive than MD care with PT. However, when combined with referral care, MD care with PT was generally less expensive. Compared with MD-only care, risk-adjusted charges (available 2006-2009) for patients in the middle risk quintile were significantly less for DC-only care.Utilization and expenditures for headache treatment increased from 2000 to 2009 across all provider groups. MD care represented the majority of total allowed charges in this study. MD care and DC care, alone or in combination, were overall the least expensive patterns of headache care. Risk-adjusted charges were significantly less for DC-only care.

Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disorder characterized by debilitating heterotopic ossification (HO). The retinoic acid receptor gamma agonist, palovarotene, and antibody-mediated activin A blockade have entered human clinical trials, but how these therapeutic modalities affect the behavior of pathogenic fibro/adipogenic progenitors (FAPs) is unclear. Using live-animal luminescence imaging, we show that transplanted pathogenic FAPs undergo rapid initial expansion, with peak number strongly correlating with HO severity. Palovarotene significantly reduced expansion of pathogenic FAPs, but was less effective than activin A inhibition, which restored wild-type population growth dynamics to FAPs. Palovarotene pretreatment did not reduce FAPs’ skeletogenic potential, indicating that efficacy requires chronic administration. Although palovarotene inhibited chondrogenic differentiation in vitro and reduced HO in juvenile FOP mice, daily dosing resulted in aggressive synovial joint overgrowth and long bone growth plate ablation. These results highlight the challenge of inhibiting pathological bone formation prior to skeletal maturation.

Contains fulltext : 50113.pdf (Publisher’s version ) (Closed access) A multiplexed fluorescence immunoassay using a novel planar waveguide technology-based microarray system, ZeptoMARK (Zeptosens), was developed to detect simultaneously urokinase-type plasminogen activator (uPA), plasminogen activator inhibitor-1 (PAI-1), and vascular endothelial growth factor (VEGF) in extracts of breast cancer tissues. The three analytes assay was cross-validated with single-analyte ELISA/chemiluminescence immunosorbent assay tests, revealing good correlations and enhanced assay sensitivities (LODs) of 1 pg/mL for uPA, 33 pg/mL for PAI-1, and 1 pg/mL for VEGF. Values were well within the 80-120% limits for assay recovery and within the +/-20% limits for assay precision. The uPA, PAI-1, and VEGF results obtained from 50 breast cancer cytosols using the protein array system demonstrated that the microarray-based multiplexed assay is a sensitive and robust tool to be used for the simultaneous quantification of cancer markers in small breast cancer tissue samples (core biopsies). The miniaturized, multiplexed assay format has a potential to be used for the quantitative analysis of a larger set of validated markers with significance in disease management.

CcmE is a heme chaperone that binds heme transiently in the periplasm of Escherichia coli and delivers it to newly synthesized and exported c -type cytochromes. The chemical nature of the covalent bond between heme and H130 is not known. We have purified soluble histidine-tagged CcmE and present its spectroscopic characteristics in the visible range. Alanine scanning mutagenesis of conserved amino acids revealed that H130 is the only residue found to be strictly required for heme binding and delivery. Mutation of the hydrophobic amino acids F37, F103, L127, and Y134 to alanine affected CcmE more than mutation of charged and polar residues. Our data are in agreement with the recently solved nuclear magnetic resonance structure of apo-CcmE (PDB code 1LIZ) and suggest that heme is bound to a hydrophobic platform at the surface of the protein and then attached to H130 by a covalent bond. Replacement of H130 with cysteine led to the formation of a covalent bond between heme and C130 at a low level. However, the H130C mutant CcmE was not active in cytochrome c maturation. Isolation and characterization of the heme-binding peptides obtained after a tryptic digest of wild-type and H130C CcmE support the hypothesis that heme is bound covalently at a vinyl group.

A series of four molecular dynamics computer simulations totaling more than 40 ns in length have been carried out on hydrated bilayer systems to study the interaction between a diacylphospholipid, 1-palmitoyl2-oleoyl-sn-glycero-3-phosphocholine (POPC), and an oligo(ethylene oxide) alkyl ether detergent, C12E4. Simulations of pure lipid bilayers, pure detergent bilayers, and a mixed system in a 5:1 lipid-to-detergent ratio, show good agreement with experimental measurements. The simulations confirm experimental observations of the membrane’s ability to significantly alter the conformations of the solute detergent molecules and offer an explanation of some seemingly contradictory experimental results. In addition to providing a molecular level explanation of the changes in solute structure, the present simulations demonstrate the importance of environment on solutes incorporated into membranes and show that molecular dynamics simulations is a tool with great potential for the study of membrane-polymer interactions.

Surface hardening improves the wear resistance of steel parts. This article focuses exclusively on the methods that involve surface and subsurface modification without any intentional buildup or increase in part dimensions. These include diffusion methods, such as carburizing, nitriding, carbonitriding, and austenitic and ferritic nitrocarburizing, as well as selective-hardening methods, such as laser transformation hardening, electron beam hardening, ion implantation, selective carburizing, and surface hardening with arc lamps. The article also discusses the factors affecting the choice of these surface-hardening methods.

Given the influence of photoperiod on reproductive development and whole-plant senescence in monocarpic plants, one would suspect that leaf senescence in these plants might be under photoperiodic control. In Arabidopsis thaliana, which is monocarpic and also a nonobligate long-day (LD) plant, LDs (16 h, 300 μmol m−2 s−1) caused leaves to die earlier than did short days (SDs, 10 h). Since leaf longevity was not paralleled by the reproductive development in the present study, the reproductive structures did not seem to be the primary controls of leaf senescence. The LD effect appeared to depend on the amount of light rather than on day length, for leaves given LDs at reduced light intensity (180 μmol m−2 s−1) lived longer than those in LDs with full light. In addition, the higher light intensity promoted chlorophyll loss and anthocyanin accumulation in LDs. Thus, senescence of these leaves seems to be governed by light dosage rather than photoperiod. Light may play a natural role in promoting the senescence of A. thaliana leaves.

Publisher Summary This chapter focuses on the light control of leaf senescence. Light control of leaf senescence reflects important environmental controls of plant development and has many practical applications as well. Light is required for the photosynthesis that sustains plant growth and long-term survival and also has many practical applications. The postharvest longevity of green vegetables and leaf-bearing cut flowers are influenced by the light signals. Lack of light for photosynthesis causes starvation and thereby senescence, and death. Although the induction of senescence by darkness is an extreme and unnatural case, photosynthesis and light excitation pressure are involved in the senescence-delaying effects of light. Light dosage effects on leaf senescence are best viewed relative to the CO 2 compensation point that light intensity where photosynthetic CO 2 fixation equals or compensates for the release of CO 2 by respiration.

Nachdem die Weiterentwicklung der Anwendungen von Informationstechnik in den letzten Jahren stark auf den unternehmensinternen und individuellen Bereich konzentriert war, ist gegenwartig ein starker Trend zu offener, institutionsuber-greifender Telekooperation zu erkennen. Durch den Medienwechsel von Papier auf Elektronik konnen neue technische Moglichkeiten genutzt werden. Gleichzeitig ist Telekooperation aber auch spezifischen Manipulationsmoglichkeiten ausgesetzt. Herkommliche technische Sicherungsmasnahmen sind fur offene Telekooperation allerdings unzureichend. Neuere technische Sicherungsfunktionen sind jedoch an umfangreiche technische, organisatorische und soziale Voraussetzungen geknupft, wenn sie Erfolg haben sollen. Erforderlich wird eine Sicherungsinfrastruktur1, deren Beschaffenheit, Voraussetzungen und Folgen allerdings noch weitgehend unbekannt sind.2 Um durch vorlaufende Technikfolgenforschung die Chancen, Risiken und Gestaltungsoptionen bestimmen zu konnen, wird ein Szenario kunftiger Sicherungsinfrastrukturen benotigt.

Asymmetric functionalisation of the benzylic methylene group in tricarbonylchromium(0) complexes of alkyl benzyl ethers[(PhCH2OR)(CO)3Cr0] is achived in high yield (86–96%) and high enantiomeric excess (ee)(97 to 99%) using chiral base methodology.

Stable crystalline tricarbonyl(indan-2-one)chromium(0)1 has been synthesised from relatively unstable indan-2-one by ketone protection, chromium complexation and ketone deprotection; addition of non-basic nucleophiles to the ketone of 1 and deprotonation/alkylation procedures proceed efficiently and stereoselectively to give good yields of diastereoisomerically pure products.

Protein microarrays are considered an enabling technology, which will significantly expand the scope of current protein expression and protein interaction analysis. Current technologies, such as two-dimensional gel electrophoresis (2-DE) in combination with mass spectrometry, allowing the identification of biologically relevant proteins, have a high resolving power, but also considerable limitations. As was demonstrated by Gygi et al. (Proc. Nat. Acad. Sci. USA 2000, 97, 9390-9395) [1], most spots in 2-DE, observed from whole cell extracts, are from high abundance proteins, whereas low abundance proteins, such as signaling molecules or kinases, are only poorly represented. Protein microarrays are expected to significantly expedite the discovery of new markers and targets of pharmaceutical interest, and to have the potential for high-throughput applications. Key factors to reach this goal are: high read-out sensitivity for quantification also of low abundance proteins, functional analysis of proteins, short assay analysis times, ease of handling and the ability to integrate a variety of different targets and new assays. Zeptosens has developed a revolutionary new bio-analytical system based on the proprietary planar waveguide technology which allows us to perform multiplexed, quantitative biomolecular interaction analysis with highest sensitivity in a microarray format upon utilizing the specific advantages of the evanescent field fluorescence detection. The analytical system, comprising an ultrasensitive fluorescence reader and microarray chips with integrated microfluidics, enables the user to generate a multitude of high fidelity data in applications such as protein expression profiling or investigating protein-protein interactions. In this paper, the important factors for developing high performance protein microarray systems, especially for targeting low abundant messengers of relevant biological information, will be discussed and the performance of the system will be demonstrated in experimental examples.

This paper develops a theoretical framework for examining the acculturation process of immigrants. Focusing on communication variables, it suggests five levels of analysis for assessing acculturation as a continuous rather than dichotomous variable: the speech act level, ritualistic communication, strategic communication, the organization of conversational discourse, and verbal information processing. Examples from research on Chinese communication are utilized to illustrate important differences between Chinese and Americans at each level of analysis. The use of this perspective offers the twofold promise of improving our understanding of “acculturation processes” in general as well as our understanding of the particular everyday communicative actions of immigrant groups. Research on Chinese communication patterns using this perspective will increase our knowledge of Chinese and American interrelations, in addition to providing insight aimed at developing better indices of acculturation of Chinese in the United States.

(1986). Situation Perception and Message Strategy Selection. Annals of the International Communication Association: Vol. 9, Communication Yearbook 9, pp. 390-420.

Amoebae of Dictyostelium discoideum, strain HL50 were mutagenized with N-methyl-N′-nitro-N-nitrosoguanidine, cloned, allowed to form pseudoplasmodia and screened for aberrant positive and negative thermotaxis. Three types of mutants were found. Mutant HO428 exhibits only positive thermotaxis over the entire temperature range (no negative thermotaxis). HO596 and HO813 exhibit weakened positive thermotaxis and normal negative thermotaxis. The weakened positive thermotactic response results in a shift toward warmer temperatures in the transition temperature from negative to positive thermotaxis. Mutant HO209 exhibits weakened positive and negative thermotactic responses and has a transition temperature similar to the ‘wild type’ (HL50). The two types of mutants represented by HO428, HO596 and HO813 support the model that positive and negative thermotaxis have separate pathways for temperature sensing. The type of mutants which contains HO209 suggests that those two pathways converge at some point before the response.

Seeds of Nigella damascena L. germinated in darkness. Incandescent light inhibited germination, with greater inhibition occurring during the latter half of the 24-h imbibitional period. The inhibitory effects of incandescent radiation depended upon irradiance; inhibition of germination by a 12-h irradiation also exhibited a broad spectrum FR irradiance dependence. An action spectrum in the region of 650-740 nm revealed that 720-nm radiation was most inhibitory, suggesting that a HIR was operative. An action of P, evidenced by photoreversible control of germination following brief R and FR irradiations, was documented when temperature was shifted upward but not when temperature was held constant.

This study explores basic processes of intercultural perception by testing the stereotyping hypothesis in intercultural relations against the individual judgment hypothesis. Videotapes of nine inter cultural (American/Chinese) hetero-sexual initial interactions were produced and interactants were rated by American subjects on six dimensions of communicative performance: linguistic skill. apprehension, dominance, helpfulness, attractiveness, and expertness. Results of the study support the individual judgment hypothesis. Implacations of the research for cross-cultural training are discussed.

One important recent trend in mass communication research and development studies is the focus on children's abilities to comprehend emotions and actions portrayed through televised drama. This study explored the social correlates of the interpretive abilities of young children in the assessment of televised narratives. In this study forty‐four pre‐school children viewed preconstructed videotapes and responded to interpretive tests. Their parents responded to a questionnaire concerning the child's background and experience with media. A number of hypotheses were tested concerning the correlates of children's comprehension skills. Though most were not confirmed, the study did demonstrate important correlations concerning the amount of TV viewing by parents and children's TV comprehension‐‐the correlations were negative, indicating that the more parents viewed TV, the worse their children performed on comprehension tests.

This study investigated the effects of situational variables on the likelihood of use of four types of compliance‐gaining strategies: justification, exchange, manipulation and personal rejection. Subjects rated the strategies on the probability that they would actually use them to gain compliance in each of four situations that varied systematically in intimacy and relational consequences. Both situational variables were found to he significant predictors of strategy preference. Message strategy selection was concluded to be based upon an assessment of the relative risk associated with the implementation of a given strategy and on the basis of the relative importance of three communicative goals: (1) whether strategy implementation would lead to successful compliance; (2) whether strategy implementation would result in relational harm; and, (3) whether strategy implementation would result in poor management of the agent's image. Recommendations for future research were noted.

(1977). Thought, Sex, and Language: The Sapir-Whorf Hypothesis in the American Women's Movement. Women's Studies in Communication: Vol. 1, No. 1, pp. 1-7.

Standardized culture methods for bryophyte plants, tissues, and propagules were developed. The methods overcome many past inconveniences and offer certain advantages that justify a broader use of bryophyte material for fundamental physiological and biochemical research. Five substrates prove to be especially advantageous for the culture of the liverwort, Marchantia polymorpha. They include vermiculite, perlite, glass cloth, nutrient agar, and nutrient solution. Selected culture conditions and vessels especially adapted to each substrate are described. The methods are contrasted for ease of culture maintenance, yields, and amenability to specific experimentation.

A naturally occurring growth regulator in extracts of Marchantia polymorpha tissues has been characterized by paper chromatography and bioassay. The endogenous compound is presumed to be indoleacetic acid (IAA) on the basis of its chromatographic behavior in five solvents, its biological activity in the Avena straight-growth test, and the utilization of synthetic IAA by thallus tissues. The endogenous level of IAA in M. polymorpha thalli was estimated. The results from the sufficiently rigorous methods employed establish for the first time the presence of IAA in a bryophyte species.

Edstrom's microphoresis technique has been employed to determine the quantitative alterations in nucleic acid content and base composition of individual cells associated with the initiation of bud primordia in Funaria hygrometrica. The filamentous protonema of this moss initiates bud cells which through repeated divisions form the leafy gametophores. The cytokinin, 6-furfurylaminopurine (kinetin), was used to induce the differentiation of bud cells from protonematal cells. The total RNA content of kinetin-induced bud cells (22.0 mumug/cell) was nearly 15 times that of protonematal cells (1.6 mumug/cell). The same dramatic increase in total RNA was apparent in bud cells which developed spontaneously in older cultures. As would be predicted, the adenine (A) to guanine (G) ratio for DNA from bud and protonematal cells was identical (0.7). The A:G ratio for RNA from bud cells (1.0) was much lower than that from protonematal cells (1.7). Thus, kinetin-induced differentiation in this system involves a dramatic increase in total RNA, the base composition of which approaches that of DNA. The base composition (A:G ratio) of DNA remains constant.

IN mammalian cells, hyperthermia causes temperature-dependent changes in cell growth parameters1, reduces DNA and protein synthesis rates2 and cell metabolism3, and leads to a loss of proliferative capacity4,5. Harris6 has shown that temperature-resistant pig kidney cells can be obtained after multiple exposures to very high thermal doses (colony-forming ability reduced to 10−5–10−6 of controls). The purpose of our experiments was to determine whether a single hyperthermic treatment (44 °C for 1 h) could induce a state of thermotolerance in cells, and if so, what was the mode of origin of the thermal resistant cells.

—Applying criteria used for higher plants, phytochrome mediation of uredospore germination in the stem-rust fungus, Puccinia graminis f. sp. tritici (Eriks & Henn) Guyot is established. A 1 min red irradiation at 660 nm promotes uredospore germination and this potentiation of promotion is photoreversible by a 1 min far-red irradiation at 730 nm.

We studied 60 nonophthalmologic patients, allocated to six treatment groups, to assess the effects of atracurium and vecuronium on intraocular pressure (IOP). All patients had IOP measured while awake, using pneumotonometry. In group 1, anesthesia was induced with thiopental, 5 mg/kg, and maintained with N2O, 70% in O2, using controlled mask ventilation, for 5 min. These patients then received atracurium, 0.5 mg/kg. After 5 additional minutes of ventilation, the trachea was intubated. From 1 min after thiopental administration until 1 min after intubation, IOP was recorded every minute. Patients in groups 2, 3, and 4 were treated identically to those in group 1, except the muscle relaxant given was atracurium, 1.0 mg/kg, vecuronium, 0.1 mg/kg, or vecuronium, 0.2 mg/kg, respectively. Patients in groups 5 and 6 underwent rapid sequence induction with thiopental, 5 mg/kg, and atracurium, 1.0 mg/kg, or vecuronium, 0.2 mg/kg, respectively. IOP was measured 1 min later, followed by intubation and IOP measurements for the next 3 min. Intraocular pressure decreased significantly in groups 1, 2, 4, and 6 after thiopental and remained stable in all groups during ventilation with N2O. Neither atracurium nor vecuronium affected IOP, nor was there any correlation between IOP and degree of neuromuscular blockade. However, IOP increased significantly after intubation in all six groups. We conclude that atracurium or vecuronium alone has no adverse effects on IOP.