The Use of 2-Octylcyanoacrylate Dressing in Reducing the Risk of Superficial Surgical Site Infections in Colorectal Stoma Surgery: A Retrospective Cohort Study.

BACKGROUND: Superficial surgical site infection (SSI) is a common morbidity following bowel resection surgery involving stoma formation with clinical and financial implications. The study aimed to evaluate the role of topical skin adhesive, 2-octylcyanoacrylate (Dermabond®) (2-OCA) in reducing wound infections following colorectal stoma surgery. METHODS: We performed a retrospective, single-centre, cohort study using clinical notes. All patients, over the age of 18, undergoing bowel resection either elective or emergency, with stoma formation over five years from January 2015 to December 2019 were included. The primary endpoint was SSI, defined by the clinical manifestation of inflammation including pain, erythema, and discharge, regardless of the microbiological culture results. Patients received either 2-OCA glue as wound dressing or standard firm adhesive wound dressing e.g. Opsite. RESULTS:  Overall, 604 patients were included in the study. The median age was 67; 187 (31%) patients received Dermabond (Group 1) and 417 (69%) received standard care (Group 2). A total of 288 (47%) patients were female, 134 (22%) had body mass index (BMI) greater than 30, 87 (14%) were diabetic, and 90 (15%) were smokers. A total of 279 (46%) patients had an American Society of Anesthesiologists (ASA) score of 3 and 4; 282 (47%) patients went through emergency surgery, 279 (64%) patients underwent dirty surgery, and 220 (35%) patients developed SSI. BMI greater than 30 compared to < 30 (OR: 2.32, 95% CI: 1.54-3.49, p<0.0001), diabetes compared to no diabetes (OR: 0.54, 95% CI: 0.32-0.92, p<0.0241), dirty surgery compared to clean surgery (OR: 2.26, 95% CI: 1.51-3.37, p<0.0001) and standard care, no 2-OCA glue use compared to the use of 2-OCA glue (OR: 1.52, 95% CI: 1.03-2.24, p=0.0343) were associated with SSIs.  Conclusion: Our study demonstrates that there is an association between 2-OCA and reduced SSIs in bowel resection surgery involving stoma formation when compared to standard methods of wound dressing. Further randomised clinical trials are recommended to strengthen this evidence and demonstrate causation.

Gauging treatment impact: The development of exposure variables in a large-scale evaluation study.

While guidance on how to design rigorous evaluation studies abounds, prescriptive guidance on how to include critical process and context measures through the construction of exposure variables is lacking. Capturing nuanced intervention dosage information within a large-scale evaluation is particularly complex. The Building Infrastructure Leading to Diversity (BUILD) initiative is part of the Diversity Program Consortium, which is funded by the National Institutes of Health. It is designed to increase participation in biomedical research careers among individuals from underrepresented groups. This chapter articulates methods employed in defining BUILD student and faculty interventions, tracking nuanced participation in multiple programs and activities, and computing the intensity of exposure. Defining standardized exposure variables (beyond simple treatment group membership) is crucial for equity-focused impact evaluation. Both the process and resulting nuanced dosage variables can inform the design and implementation of large-scale, diversity training program, outcome-focused, evaluation studies.

Methodological Problems With Online Concussion Testing.

Reaction time testing is widely used in online computerized concussion assessments, and most concussion studies utilizing the metric have demonstrated varying degrees of difference between concussed and non-concussed individuals. The problem with most of these online concussion assessments is that they predominantly rely on consumer grade technology. Typical administration of these reaction time tests involves presenting a visual stimulus on a computer monitor and prompting the test subject to respond as quickly as possible via keypad or computer mouse. However, inherent delays and variabilities are introduced to the reaction time measure by both computer and associated operating systems that the concussion assessment tool is installed on. The authors hypothesized systems that are typically used to collect concussion reaction time data would demonstrate significant errors in reaction time measurements. To remove human bias, a series of experiments was conducted robotically to assess timing errors introduced by reaction time tests under four different conditions. In the first condition, a visual reaction time test was conducted by flashing a visual stimulus on a computer monitor. Detection was via photodiode and mechanical response was delivered via computer mouse. The second condition employed a mobile device for the visual stimulus, and the mechanical response was delivered to the mobile device's touchscreen. The third condition simulated a tactile reaction time test, and mechanical response was delivered via computer mouse. The fourth condition also simulated a tactile reaction time test, but response was delivered to a dedicated device designed to store the interval between stimulus delivery and response, thus bypassing any problems hypothesized to be introduced by computer and/or computer software. There were significant differences in the range of responses recorded from the four different conditions with the reaction time collected from visual stimulus on a mobile device being the worst and the device with dedicated hardware designed for the task being the best. The results suggest that some of the commonly used visual tasks on consumer grade computers could be (and have been) introducing significant errors for reaction time testing and that dedicated hardware designed for the reaction time task is needed to minimize testing errors.

Adhesive and Cohesive Peel Force Measurement of Human Airway Mucus.

In health, the high-speed airflow associated with cough represents a vital backup mechanism for clearing accumulated mucus from our airways. However, alterations in the mucus layer in cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) leads to the mucus layer adhered to the airway surfaces, representing the nidus of chronic lung infection. To understand what is different about diseased mucus and why cough clearance is defective, there is a need for techniques to quantify the strength of the interactions limiting the ability of airflow to strip mucus from the airway surface (i.e., adhesive strength) or tear mucus apart (i.e., cohesive strength). To overcome the issues with measuring these properties in a soft (i.e., low elastic modulus) mucus layer, we present here novel peel-testing technologies capable of quantifying the mucus adhesive strength on cultured airway cells and cohesive strength of excised mucus samples. While this protocol focuses on measurements of airway mucus, this approach can easily be adapted to measuring adhesive/cohesive properties of other soft biological materials.

Discusión en torno a la vacunación profiláctica contra el virus del papiloma humano / Discussion of human papillomavirus prophylactic vaccination / Discussió sobre la vacunció profilàctica contra el virus del papil-loma humà

En el presente artículo se aborda la problemática en torno al virus del papiloma humano -el cual causa diversos cánceres, destacando el cáncer cervicouterino-, y la vacunación para prevenir contra dicha infección. Primero, se describen la morbilidad y la mortalidad del virus y las características de las vacunas. Segundo, se discuten los problemas referentes a la eficacia y la seguridad de las vacunas. Tercero, se discuten dos problemas éticos en torno a la vacunación contra el VPH: ¿debe ser obligatoria u opcional?, ¿debe aplicarse solo a mujeres o también a varones? Se concluye con un llamado a extender la vacunación contra el VPH y la educación en torno a él en particular, y a la vacunación en general

In this article, the problem surrounding human papillomavirus- which causes some cancers, among which cervical cancer is the most prominent- and the prophylactic vaccination against it is addressed. First, the most relevant facts about both the virus and the vaccines are described. Second, the problems of the efficacy and safety of the vaccines are discussed. Third, two ethical problems of HPV vaccination are discussed: should it be obligatory or optional? Should it target only women or men too? I conclude with a call to extend HPV vaccination and HPV education in particular, and vaccination education in general

En el present article s'aborda la problemàtica sobre el virus del papil·loma humà -que causa diversos càncers, en especial el càncer de cèrvix i d’úter-, i la vacunació per prevenir aquesta infecció. Primer, es descriuen la morbiditat i la mortalitat del virus i les característiques de les vacunes. Segon, es discuteixen els problemes referents a l'eficàcia i la seguretat de les vacunes. Tercer, es discuteixen dos problemes ètics entorn de la vacunació contra el VPH: ha de ser obligatòria o opcional?, ha d'aplicar-se només a dones o també a homes? Es conclou amb una crida a estendre la vacunació contra el VPH i l'educació sobre la vacunació en general

Proficiency in pole handling during Nordic walking influences exercise effectiveness in middle-aged and older adults.

Nordic walking (NW) is a total body version of walking increasingly used as a health-promoting activity by middle-aged and older adults. The present study examined the relationship between force exerted through the pole and physiological response during NW. In this non-randomized exercise trial, 17 participants comprising 8 middle-aged and older recreationally trained Nordic walkers (NWrec: 63.7 ± 8.1 years) and 9 experienced NW instructors (NWinstr: 57.5 ± 7.8 years) underwent outdoor ordinary walking (OW) and NW bouts as fast as possible for 12 minutes. Walking distance, speed, heart rate (HR), energy expenditure (METs and J/kg/m) and upper and lower limb muscle activities using surface electromyogram (EMG) were assessed. A pole with a built-in load cell measured force applied to the pole with peak pole force, pole contact time, % of pole contact time with respect to the gait cycle, and pole impulse derived. We conducted two-way analysis of covariance adjusted for age and BMI. There was a significant group and walking type interaction for walking distance and speed (P = 0.04), METs (P < 0.01), and HR (P = 0.04) with higher values in the NWinstr group during NW than OW. As expected, upper limb EMG activities increased (P < 0.01) with NW in both groups. All pole force measures were significantly higher in NWinstr than NWrec (P ≤ 0.01). Change in walking distance and speed were correlated with pole peak force (r = 0.67, P < 0.01) and pole impulse (r = 0.63, P = 0.01). Similarly, change in METs was associated with peak pole force (r = 0.66, P < 0.01) and pole impulse (r = 0.56, P = 0.02). These results indicate that planting the pole on the ground more forcefully and for longer periods to derive a driving force in NW enhances the effectiveness of the exercise and potentially the health-derived benefits.

Roles of mucus adhesion and cohesion in cough clearance.

Clearance of intrapulmonary mucus by the high-velocity airflow generated by cough is the major rescue clearance mechanism in subjects with mucoobstructive diseases and failed cilial-dependent mucus clearance, e.g., subjects with cystic fibrosis (CF) or chronic obstructive pulmonary disease (COPD). Previous studies have investigated the mechanical forces generated at airway surfaces by cough but have not considered the effects of mucus biophysical properties on cough efficacy. Theoretically, mucus can be cleared by cough from the lung by an adhesive failure, i.e., breaking mucus-cell surface adhesive bonds and/or by cohesive failure, i.e., directly fracturing mucus. Utilizing peel-testing technologies, mucus-epithelial surface adhesive and mucus cohesive strengths were measured. Because both mucus concentration and pH have been reported to alter mucus biophysical properties in disease, the effects of mucus concentration and pH on adhesion and cohesion were compared. Both adhesive and cohesive strengths depended on mucus concentration, but neither on physiologically relevant changes in pH nor bicarbonate concentration. Mucus from bronchial epithelial cultures and patient sputum samples exhibited similar adhesive and cohesive properties. Notably, the magnitudes of both adhesive and cohesive strength exhibited similar velocity and concentration dependencies, suggesting that viscous dissipation of energy within mucus during cough determines the efficiency of cough clearance of diseased, hyperconcentrated, mucus. Calculations of airflow-induced shear forces on airway mucus related to mucus concentration predicted substantially reduced cough clearance in small versus large airways. Studies designed to improve cough clearance in subjects with mucoobstructive diseases identified reductions of mucus concentration and viscous dissipation as key therapeutic strategies.

Neurosensory Assessments of Concussion.

The purpose of this research was to determine if cortical metrics-a unique set of sensory-based assessment tools-could be used to characterize and differentiate concussed individuals from nonconcussed individuals. Cortical metrics take advantage of the somatotopic relationship between skin and cortex, and the protocols are designed to evoke interactions between adjacent cortical regions to investigate fundamental mechanisms that mediate cortical-cortical interactions. Student athletes, aged 18 to 22 years, were recruited into the study through an athletic training center that made determinations of postconcussion return-to-play status. Sensory-based performance tasks utilizing vibrotactile stimuli applied to tips of the index and middle fingers were administered to test an individual's amplitude discrimination, temporal order judgment, and duration discrimination capacity in the presence and absence of illusion-inducing conditioning stimuli. Comparison of the performances in the presence and absence of conditioning stimuli demonstrated differences between concussed and nonconcussed individuals. Additionally, mathematically combining results from the measures yields a unique central nervous system (CNS) profile that describes an individual's information processing capacity. A comparison was made of CNS profiles of concussed vs. nonconcussed individuals and demonstrated with 99% confidence that the two populations are statistically distinct. The study established solid proof-of-concept that cortical metrics have significant potential as a quantitative biomarker of CNS status.

Use of a venting PEG tube in the management of recurrent acute gastric dilatation associated with Prader-Willi syndrome.

A patient with Prader-Willi Syndrome was admitted to the ICU with features of recurrent acute gastric dilatation, aspiration pneumonia and a massive pulmonary embolus. He was initially managed with intubation, assisted ventilation, intravenous fluids and anticoagulation. Decompression of the stomach was achieved with a nasogastric tube. After ventilator weaning, he did not tolerate the nasogastric intubation that led to a further episode of aspiration pneumonia as a result of non-resolving gastric dilatation. He required readmission to intensive care for a further period of ventilatory support. While the patient was sedated and ventilated, a venting percutaneous endoscopic gastrostomy (PEG) with a jejunal feeding extension was placed, permitting both continued decompression of the stomach and enteral feeding. The patient tolerated the PEG-J well and his nutritional needs were successfully addressed. Oral intake was slowly re-established with ongoing decompression of the stomach with the PEG. He was discharged from hospital with the PEG in place.

Maternal immune activation induces GAD1 and GAD2 promoter remodeling in the offspring prefrontal cortex.

Maternal infection during pregnancy increases the risk of neurodevelopmental disorders in the offspring. In addition to its influence on other neuronal systems, this early-life environmental adversity has been shown to negatively affect cortical γ-aminobutyric acid (GABA) functions in adult life, including impaired prefrontal expression of enzymes required for GABA synthesis. The underlying molecular processes, however, remain largely unknown. In the present study, we explored whether epigenetic modifications represent a mechanism whereby maternal infection during pregnancy can induce such GABAergic impairments in the offspring. We used an established mouse model of prenatal immune challenge that is based on maternal treatment with the viral mimetic poly(I:C). We found that prenatal immune activation increased prefrontal levels of 5-methylated cytosines (5mC) and 5-hydroxymethylated cytosines (5hmC) in the promoter region of GAD1, which encodes the 67-kDa isoform of the GABA-synthesising enzyme glutamic acid decarboxylase (GAD67). The early-life challenge also increased 5mC levels at the promoter region of GAD2, which encodes the 65-kDa GAD isoform (GAD65). These effects were accompanied by elevated GAD1 and GAD2 promoter binding of methyl CpG-binding protein 2 (MeCP2) and by reduced GAD67 and GAD65 mRNA expression. Moreover, the epigenetic modifications at the GAD1 promoter correlated with prenatal infection-induced impairments in working memory and social interaction. Our study thus highlights that hypermethylation of GAD1 and GAD2 promoters may be an important molecular mechanism linking prenatal infection to presynaptic GABAergic impairments and associated behavioral and cognitive abnormalities in the offspring.

Development of a Cyclic Strain Bioreactor for Mechanical Enhancement and Assessment of Bioengineered Myocardial Constructs.

The purpose of this study was to develop enabling bioreactor technologies using a novel voice coil actuator system for investigating the effects of periodic strain on cardiac patches fabricated with rat cardiomyocytes. The bioengineered muscle constructs used in this study were formed by culturing rat neonatal primary cardiac cells on a fibrin gel. The physical design of the bioreactor was initially conceived using Solidworks to test clearances and perform structural strain analysis. Once the software design phase was completed the bioreactor was assembled using a combination of commercially available, custom machined, and 3-D printed parts. We utilized the bioreactor to evaluate the effect of a 4-h stretch protocol on the contractile properties of the tissue after which immunohistological assessment of the tissue was also performed. An increase in contractile force was observed after the strain protocol of 10% stretch at 1 Hz, with no significant increase observed in the control group. Additionally, an increase in cardiac myofibril alignment, connexin 43 expression, and collagen type I distribution were noted. In this study we demonstrated the effectiveness of a new bioreactor design to improve contractility of engineered cardiac muscle tissue.

Atomic Layer Deposition of Hafnium(IV) Oxide on Graphene Oxide: Probing Interfacial Chemistry and Nucleation by using X-ray Absorption and Photoelectron Spectroscopies.

Interfacing graphene with metal oxides is of considerable technological importance for modulating carrier density through electrostatic gating as well as for the design of earth-abundant electrocatalysts. Herein, we probe the early stages of the atomic layer deposition (ALD) of HfO2 on graphene oxide using a combination of C and O K-edge near-edge X-ray absorption fine structure spectroscopies and X-ray photoelectron spectroscopy. Dosing with water is observed to promote defunctionalization of graphene oxide as a result of the reaction between water and hydroxyl/epoxide species, which yields carbonyl groups that further react with migratory epoxide species to release CO2 . The carboxylates formed by the reaction of carbonyl and epoxide species facilitate binding of Hf precursors to graphene oxide surfaces. The ALD process is accompanied by recovery of the π-conjugated framework of graphene. The delineation of binding modes provides a means to rationally assemble 2D heterostructures.

Emptying and filling a tunnel bronze.

The classical orthorhombic layered phase of V2O5 has long been regarded as the thermodynamic sink for binary vanadium oxides and has found great practical utility as a result of its open framework and easily accessible redox states. Herein, we exploit a cation-exchange mechanism to synthesize a new stable tunnel-structured polymorph of V2O5 (ζ-V2O5) and demonstrate the subsequent ability of this framework to accommodate Li and Mg ions. The facile extraction and insertion of cations and stabilization of the novel tunnel framework is facilitated by the nanometer-sized dimensions of the materials, which leads to accommodation of strain without amorphization. The topotactic approach demonstrated here indicates not just novel intercalation chemistry accessible at nanoscale dimensions but also suggests a facile synthetic route to ternary vanadium oxide bronzes (M x V2O5) exhibiting intriguing physical properties that range from electronic phase transitions to charge ordering and superconductivity.

Programmable mechanobioreactor for exploration of the effects of periodic vibratory stimulus on mesenchymal stem cell differentiation.

A programmable bioreactor using a voice-coil actuator was developed to enable research on the effects of periodic vibratory stimulus on human and porcine mesenchymal stem cells (MSCs). We hypothesized that low frequency vibrations would result in a cartilage phenotype and higher frequency vibrations would result in a bone phenotype. The mechanical stimulation protocol is adjusted from a computer external to the incubator via a USB cable. Once programmed, the embedded microprocessor and sensor system on the bioreactor execute the protocol independent of the computer. In each test, a sinusoidal stimulus was applied to a culture plate in 1-min intervals with a 15-min rest following each, for a total of 15 h per day for 10 days. Frequencies of 1 and 100 Hz were applied to cultures of both human and porcine umbilical cord-derived MSCs. Chondrogenesis was determined by Alcian blue staining for glycosaminoglycans and an increased differentiation index (ratio of mRNA for collagen II and collagen I). Osteogenic differentiation was indicated with Alizarin red for calcium staining and increased bone morphogenetic protein 2 mRNA. One-hertz stimulation resulted in a cartilage phenotype for both human and porcine MSCs, while 100-Hz stimulation resulted in a bone phenotype.

An electronic structure perspective of graphene interfaces.

The unusual electronic structure of graphene characterized by linear energy dispersion of bands adjacent to the Fermi level underpins its remarkable transport properties. However, for practical device integration, graphene will need to be interfaced with other materials: 2D layered structures, metals (as ad-atoms, nanoparticles, extended surfaces, and patterned metamaterial geometries), dielectrics, organics, or hybrid structures that in turn are constituted from various inorganic or organic components. The structural complexity at these nanoscale interfaces holds much promise for manifestation of novel emergent phenomena and provides a means to modulate the electronic structure of graphene. In this feature article, we review the modifications to the electronic structure of graphene induced upon interfacing with disparate types of materials with an emphasis on iterative learnings from theoretical calculations and electronic spectroscopy (X-ray absorption fine structure (XAFS) spectroscopy, scanning transmission X-ray microscopy (STXM), angle-resolved photoemission spectroscopy (ARPES), and X-ray magnetic circular dichroism (XMCD)). We discuss approaches for engineering and modulating a bandgap in graphene through interfacial hybridization, outline experimental methods for examining electronic structure at interfaces, and overview device implications of engineered interfaces. A unified view of how geometric and electronic structure are correlated at interfaces will provide a rational means for designing heterostructures exhibiting emergent physical phenomena with implications for plasmonics, photonics, spintronics, and engineered polymer and metal matrix composites.

Biochemical properties of tissue-engineered cartilage.

OBJECTIVE: Microtia is treated with rib cartilage sculpting and staged procedures; though aesthetically pleasing, these constructs lack native ear flexibility. Tissue-engineered (TE) elastic cartilage may bridge this gap; however, TE cartilage implants lead to hypertrophic changes with calcification and loss of flexibility. Retaining flexibility in TE cartilage must focus on increased elastin, maintained collagen II, decreased collagen X, with prevention of calcification. This study compares biochemical properties of human cartilage to TE cartilage from umbilical cord mesenchymal stem cells (UCMSCs). Our goal is to establish a baseline for clinically useful TE cartilage. METHODS: Discarded cartilage from conchal bowl, microtic ears, preauricular tags, rib, and TE cartilage were evaluated for collagen I, II, X, calcium, glycosaminoglycans, elastin, and fibrillin I and III. Human UCMSCs were chondroinduced on 2D surfaces and 3D D,L-lactide-co-glycolic acid (PLGA) fibers. RESULTS: Cartilage samples demonstrated similar staining for collagens I, II, and X, elastin, and fibrillin I and III, but differed from rib. TE pellets and PLGA-supported cartilage were similar to auricular samples in elastin and fibrillin I staining. TE samples were exclusively stained for fibrillin III. Only microtic samples demonstrated calcium staining. CONCLUSIONS: TE cartilage expressed similar levels of elastin, fibrillin I, and collagens I and X when compared to native cartilage. Microtic cartilage demonstrated elevated calcium, suggesting this abnormal tissue may not be a viable cell source for TE cartilage. TE cartilage appears to recapitulate the embryonic development of fibrillin III, which is not expressed in adult tissue, possibly providing a strategy to control TE elastic cartilage phenotype.

Inside and Outside: X-ray Absorption Spectroscopy Mapping of Chemical Domains in Graphene Oxide.

The oxidative chemistry of graphite has been investigated for over 150 years and has attracted renewed interest given the importance of exfoliated graphene oxide as a precursor to chemically derived graphene. However, the bond connectivities, steric orientations, and spatial distribution of functional groups remain to be unequivocally determined for this highly inhomogeneous nonstoichiometric material. Here, we demonstrate the application of principal component analysis to scanning transmission X-ray microscopy data for the construction of detailed real space chemical maps of graphene oxide. These chemical maps indicate very distinct functionalization motifs at the edges and interiors and, in conjunction with angle-resolved near-edge X-ray absorption fine structure spectroscopy, enable determination of the spatial location and orientations of functional groups. Chemical imaging of graphene oxide provides experimental validation of the modified Lerf-Klinowski structural model. Specifically, we note increased contributions from carboxylic acid moieties at edge sites with epoxide and hydroxyl species dominant within the interior domains.

RMP-02/MTN-006: A phase 1 rectal safety, acceptability, pharmacokinetic, and pharmacodynamic study of tenofovir 1% gel compared with oral tenofovir disoproxil fumarate.

This study was designed to assess the safety, acceptability, pharmacokinetic (PK), and pharmacodynamic (PD) responses to rectal administration of tenofovir (TFV) 1% vaginally formulated gel and oral tenofovir disoproxil fumarate (TDF). This study was designed as a phase 1, randomized, two-site (United States), double-blind, placebo-controlled study of sexually abstinent men and women. Eighteen participants received a single 300-mg exposure of oral TDF and were then randomized 2:1 to receive a single and then seven daily exposures of rectal TFV or hydroxyethyl cellulose (HEC) placebo gel. Safety endpoints included clinical adverse events (AEs) and mucosal safety parameters. Blood and colonic biopsies were collected for PK analyses and ex vivo HIV-1 challenge. No serious AEs were reported. However, AEs were significantly increased with 7-day TFV gel use, most prominently with gastrointestinal AEs (p=0.002). Only 25% of participants liked the TFV gel. Likelihood of use "if somewhat protective" was ∼75% in both groups. Indices of mucosal damage showed minimal changes. Tissue TFV diphosphate (TFV-DP) C(max) 30 min after single rectal exposure was 6-10 times greater than single oral exposure; tissue TFV-DP was 5.7 times greater following 7-day versus single rectal exposure. In vivo exposure correlated with significant ex vivo tissue infectibility suppression [single-rectal: p=0.12, analysis of covariance (ANCOVA) p=0.006; 7-day rectal: p=0.02, ANCOVA p=0.005]. Tissue PK-PD was significantly correlated (p=0.002). We conclude that rectal dosing with TFV 1% gel resulted in greater TFV-DP tissue detection than oral dosing with reduced ex vivo biopsy infectibility, enabling PK-PD correlations. On the basis of increased gastrointestinal AEs, rectally applied, vaginally formulated TFV was not entirely safe or acceptable, suggesting the need for alternative rectal-specific formulations.

From Grignard's reagents to well-defined Mg nanostructures: distinctive electrochemical and solution reduction routes.

Anisotropic Mg nanowires have been successfully prepared by electrocrystallization of Grignard's reagents thought to proceed via a modified faces, steps, and kinks (FSK) mechanism. Mg nanoparticles with roughly hexagonal shapes have also been obtained via chemical reduction of the same Grignard's reagents.

A novel device for the study of somatosensory information processing.

Current methods for applying multi-site vibratory stimuli to the skin typically involve the use of multiple, individual vibrotactile stimulators. Limitations of such an arrangement include difficulty with both positioning the stimuli as well as ensuring that stimuli are delivered in a synchronized and deliberate manner. Previously, we reported a two-site tactile stimulator that was developed in order to solve these problems (Tannan et al., 2007a). Due to both the success of that novel stimulator and the limitations that were inherent in that device, we designed and fabricated a four-site stimulator that provides a number of advantages over the previous version. First, the device can stimulate four independent skin sites and is primarily designed for stimulating the digit tips. Second, the positioning of the probe tips has been re-designed to provide better ergonomic hand placement. Third, the device is much more portable than the previously reported stimulator. Fourth, the stimulator head has a much smaller footprint on the table or surface where it resides. To demonstrate the capacity of the device for delivering tactile stimulation at four independent sites, a finger agnosia protocol, in the presence and absence of conditioning stimuli, was conducted on seventeen healthy control subjects. The study demonstrated that with increasing amplitudes of vibrotactile conditioning stimuli concurrent with the agnosia test, inaccuracies of digit identification increased, particularly at digits D3 and D4. The results are consistent with prior studies that implicated synchronization of adjacent and near-adjacent cortical ensembles with conditioning stimuli in impacting TOJ performance (Tommerdahl et al., 2007a,b).