Rationale and design of a randomized study comparing the Watchman FLX device to DOACs in patients with atrial fibrillation

BACKGROUND

Percutaneous left atrial appendage (LAA) closure (LAAC) was developed as a nonpharmacologic alternative to oral anticoagulants (OACs) in patients with atrial fibrillation (AF) who are at an increased risk for stroke or systemic embolism. The Watchman device permanently seals off the LAA to prevent thrombi from escaping into the circulation. Previous randomized trials have established the safety and efficacy of LAAC compared to warfarin. However, direct OACs (DOACs) have become the preferred pharmacologic strategy for stroke prevention in patients with AF, and there is limited data comparing Watchman FLX to DOACs in a broad AF patient population. CHAMPION-AF is designed to prospectively determine whether LAAC with Watchman FLX is a reasonable first-line alternative to DOACs in patients with AF who are indicated for OAC therapy.

STUDY DESIGN

A total of 3,000 patients with a CHA2DS2-VASc score ≥2 (men) or ≥3 (women) were randomized to Watchman FLX or DOAC in a 1:1 allocation at 142 global clinical sites. Patients in the device arm were to be treated with DOAC and aspirin, DOAC alone, or DAPT for at least 3 months postimplant followed by aspirin or P2Y12 inhibitor for 1-year. Control patients were required to take an approved DOAC for the duration of the trial. Clinical follow-up visits are scheduled at 3- and 12-months, and then annually through 5 years; LAA imaging is required at 4 months in the device group. Two primary end points will be evaluated at 3 years: (1) composite of stroke (ischemic/hemorrhagic), cardiovascular death, and systemic embolism compared for noninferiority, and (2) nonprocedural bleeding (International Society on Thrombosis and Haemostasis [ISTH] major and clinically relevant nonmajor bleeding) tested for superiority in the device arm against DOACs. The third primary noninferiority end point is the composite of ischemic stroke and systemic embolism at 5 years. Secondary end points include 3- and 5-year rates of (1) ISTH-defined major bleeding and (2) the composite of cardiovascular death, all stroke, systemic embolism, and nonprocedural ISTH bleeding.

CONCLUSIONS

This study will prospectively evaluate whether LAAC with the Watchman FLX device is a reasonable alternative to DOACs in patients with AF.

CLINICAL TRIAL REGISTRATION

NCT04394546.

An additional simultaneous magnetic ordering and magneto-capacitive behavior with dielectric relaxation besides multiferroicity in Fe1-xTexVO4

Here we report the evidence of an additional magnetic ordering and frequency dispersive magneto-dielectric (MD) permittivity besides multiferroic behavior in Te⁴⁺(S= 0) doped FeVO₄. Two antiferromagnetic transitions similar to FeVO₄at ∼21.86 K (TN1) and 16.03 K (TN2) were observed in all samples. An additional novel defect clusters based magnetic ordering at relatively higher temperature (TAMO) ∼ 203 K is also observed from the magnetization. Evaluated magnetic moments show systematic decrease and the magnetic frustration factors show an increase with the increasing of Te⁴⁺(S= 0) content. MD studies show stable ferroelectric ordering at spiral magnetic transition (TN2) and the multiferroic order persists to the largest doping of Te (x= 0.10). The MD studies also reveal a magneto-capacitive (MC) behavior at TAMO(∼203 K) with a high dielectric constant and loss, and the possible reason for the magnetic ordering and MC behavior is ascribed to short range magnetic clustering arising out of defect based mechanisms. Mössbauer spectroscopic studies confirm local structural correlation with magnetic and ferroelectric ordering.

Stabilizing effects of Ag doping on structure and thermal stability of FeN thin films

In this work, we investigated the effect of Ag doping (2-20 at.%) on the phase formation of iron mononitride (FeN) thin films. Together with deposition of FeN using reactive dc magnetron sputtering, Ag was also co-sputtered at various doping levels between 2-20 at.%. We found that doping of Ag around 5 at.% is optimum to not only improve the thermal stability of FeN but also to reduce intrinsic defects that are invariably present in (even in epitaxial) FeN. Conversion electron Mössbauer spectroscopy and N K-edge x-ray near edge absorption measurements clearly reveal a reduction of defects in Ag doped FeN samples. Moreover, Fe self-diffusion measurements carried out using secondary ion mass spectroscopy depth-profiling and polarized neutron reflectivity in57Fe enriched samples exhibit an appreciable reduction in Fe self-diffusion in Ag doped FeN samples. Ag being immiscible with Fe and non-reactive with N, occupies grain-boundary positions as nanoparticles and prohibits the fast Fe self-diffusion in FeN.

Domain state modulation by interfacial diffusion in FePt/FeCo thin films: experimental approach with micromagnetic modelling

We report the complex implications of inter-diffusion between polycrystalline FePt/FeCo layers as an impact of the FeCo underlayer on the structural and magnetic properties of the system. The crystalline growth of FePt strongly reduces in an entirely diffused system compared to the one with lesser diffusion, while the crystalline structure of FeCo is apparently less affected. Charge redistribution occurs between Fe, Co and Pt ensuring increased Co-Pt and Fe-Pt interactions with higher diffusion. Thereafter, we combine hysteresis and magnetic force microscopy measurements to show that the interfacial deformations result in the distinct out-plane magnetic behaviour of the system. FeCo@FePt nano-composite like structure, originating due to interfacial diffusion, shows interactions between two magnetic phases with in-plane low anisotropy exhibiting wasp-shaped out-plane hysteresis loop. Whereas the layered structure of FePt/FeCo films shows random anisotropy with a significant out-plane contribution even in the polycrystalline films. Micromagnetic modelling demonstrates coercivity deterioration and reduction of switching field due to the formation of a slightly diffused interface. Contrarily, the experimental observations for complete diffusion between the two layers are explained by simulating the inhomogeneous distribution of anisotropies along the film plane. These studies provide deep perceptions of the magnetic properties of FePt/FeCo system governed by diffusion kinetics which are valuable to achieve desired magnetic characteristics using this system.

Strain healing of spin-orbit coupling:a cause for enhanced magnetic moment in epitaxial SrRuO3 thin films

Enhanced magnetic moment and coercivity in SrRuO₃ thin films are significant issues for advanced technological usages and hence are researched extensively in recent times. Most of the previous reports on thin films with enhanced magnetic moment attributed it to the high spin state. Our magnetization results show high magnetic moment of 3.3 μ_B/Ru ion in the epitaxial thin films grown on LSAT substrate against 1.2 μ_B/Ru ion observed in bulk compound. Contrary to the previous reports the Ru ions are found to be in low spin state and the orbital moment is shown to be contributing significantly in the enhancement of magnetic moment. We employed x-ray absorption spectroscopy and resonant valance band spectroscopy to probe the spin state and orbital contributions in these films. The existence of strong spin-orbit coupling responsible for the de-quenching of the 4d orbitals is confirmed by the observation of the non-statistical large branching ratio at the Ru M_2,3 absorption edges. X-ray magnetic circular dichroism studies performed at the Ru M_2,3 edges provided direct evidence of significant contribution of orbital moment in the film grown on LSAT. The relaxation of orbital quenching by strain engineering provides a new tool for enhancing magnetic moment and strain disorder is shown to be an efficient mean to control the spin-orbit coupling.

Role of Ni substitution on structural, magnetic and electronic properties of epitaxial CoCr2O4 spinel thin films

Cubic spinel CoCr2O4 has recently attained attention due to its multiferroic properties. However, the Co site substitution effect on the structural and magnetic properties has rarely been studied in thin film form. In this work, the structural and magnetic properties of Co1-x Ni x Cr2O4 (x= 0, 0.5) epitaxial thin films deposited on MgAl2O4 (100) and MgO (100) substrates to manipulate the nature of strain in the films using pulsed laser deposition (PLD) technique are presented. The epitaxial nature of the films was manifested through x-ray diffraction (XRD), reciprocal space mapping (RSM) and Rutherford backscattering spectrometry (RBS) measurements. Raman measurements revealed a disappearance of characteristic A 1 g and F 2 g modes of the CoCr2O4 with increase in the Ni content. Atomic force microscopy (AFM) and field emission scanning electron microscopy (FE-SEM) studies show a modification of the surface morphology upon Ni substitution. Magnetic measurements disclose that the ferrimagnetic Curie temperature (T C) of the CoCr2O4 in thin film grown on MgAl2O4 (100) and MgO (100) substrates were found to be 100.6 ± 0.5 K and 93.8 ± 0.2 K, respectively. With Ni substitution the T C values were found to be enhanced to 104.5 ± 0.4 K for MgAl2O4 (100) and 108.5 ± 0.6 K for MgO (100) substrates. X-ray photoelectron spectroscopy (XPS) suggests Cr3+ oxidation states in the films, while Co ions are present in a mixed Co2+/Co3+ oxidation state. The substitution of Ni at Co site significantly modifies the line shape of the core level as well as the valence band. Ni ions are also found to be in a mixed 2+/3+ oxidation state. O 1s core level display asymmetry related to possible defects like oxygen vacancies in the films.

Vibrational spectra and optical properties of Fe1-xCrxVO4 solid solutions: With a group theory analysis

The present manuscript reports vibrational spectra and optical studies of polycrystalline Fe_1-xCr_xVO₄ solid solutions through FT-IR spectroscopy augmented with a group theory (G.T.) analysis and UV-Visible DRS spectroscopy. Full set of IR and Raman modes are determined by G. T. for various crystal symmetries in FeVO₄-CrVO₄ solid solutions where Triclinic, Monoclinic and Orthorhombic structures evolve with increasing Cr concentration. Experimentally obtained vibrational modes support the structural phase transitions and confirm formation of continuous solid solutions in Fe_1-xCr_xVO₄. The Diffuse Reflectance Spectra (DRS) of Fe_1-xCr_xVO₄ depicts the electronic structure and different optical transitions due to absorption of photon energy. The d-d transitions are manifested for all compounds in terms of crystal field stabilization energy (CFSE) caused by distorted lattice sites. The band gap energy of Fe_1-xCr_xVO₄ is calculated using Tauc formula. It shows a red shift initially within triclinic structure then blue shift with the increase of Cr concentration. Urbach energy (E_u) tails in the spectra show the electronic structural disorder in Fe_1-xCr_xVO₄ due to impurity energy levels of Cr ions within band gap region. It is observed that E_u decreases with the doping concentration due to the increase in crystal symmetry corresponding to the structural phase transitions in Fe_1-xCr_xVO₄.

Effect of thermal annealing on the phase evolution of silver tungstate in Ag/WO₃ films

Silver/tungsten oxide multi-layer films are deposited over quartz substrates by RF magnetron sputtering technique and the films are annealed at temperatures 200, 400 and 600°C. The effect of thermal annealing on the phase evolution of silver tungstate phase in Ag/WO3 films is studied extensively using techniques like X-ray diffraction, micro-Raman analysis, atomic force microscopy and photoluminescence studies. The XRD pattern of the as-deposited film shows only the peaks of cubic phase of silver. The film annealed at 200°C shows the presence of XRD peaks corresponding to orthorhombic phase of Ag2WO4 and peaks corresponding to cubic phase of silver with reduced intensity. It is found that, as annealing temperature increases, the volume fraction of Ag decreases and that of Ag2WO4 phase increases and becomes highest at a temperature of 400°C. When the temperature increases beyond 400°C, the volume fraction of Ag2WO4 decreases, due to its decomposition into silver and oxygen deficient phase Ag2W4O13. The micro-Raman spectra of the annealed films show the characteristic bands of tungstate phase which is in agreement with XRD analysis. The surface morphology of the films studied by atomic force microscopy reveals that the particle size and r.m.s roughness are highest for the sample annealed at 400°C. In the photoluminescence study, the films with silver tungstate phase show an emission peak in blue region centered around the wavelength 441 nm (excitation wavelength 256 nm).

Structural, magnetic and electronic structure studies of NdFe(1-x)Ni(x)O(3) (0 ≤ x ≤ 0.3)

We present here the structural, electronic structure, magnetic and Mössbauer studies of NdFe(1-x)Ni(x)O(3) (0≤x≤0.3) samples. All the samples exhibit a single-phase orthorhombic structure with space group Pbnm. The near-edge x-ray absorption fine structure (NEXAFS) studies reveal that, with the Ni substitution at Fe sites, a new spectral feature about 1.5 eV lower than the pre-edge structure of NdFeO(3) in the O K edge is observed due to the 3d contraction effect and is growing monotonically with the increase of Ni concentration. The Fe L(3,2), Ni L(3,2) and Nd M(5,4) edges confirm the trivalent state of Fe, Ni and Nd ions. The Mössbauer spectra fitted with two Zeeman sextets confirm the different surroundings of Ni around Fe ions. With the increase in Ni concentration, the sextets are broadened. The increase of quadrupole splitting and the decrease of the hyperfine field suggest the change in the ordered regime of the system. The magnetic behaviour at low temperatures is explained in the context of competition among moments of rare earth (Nd) and transition metal ions (Fe/Ni). The strong paramagnetic contribution of the Nd magnetic sublattice and spin flip phenomenon is observed from the temperature dependence of zero-field-cooled and field-cooled magnetization where spin crossover is observed. The isothermal hysteresis loops show a decrease of magnetization and increase of coercivity with the increase in temperature and complements magnetization versus temperature. The results are explained on the basis of the spin reorientation phenomenon.

Growth of textured nanocrystalline cobalt ferrite thin films by pulsed laser deposition

Cobalt ferrite thin films have been deposited on fused quartz substrates by pulsed laser deposition at various substrate temperatures, T(s) (25 degrees C, 300 degrees C, 550 degrees C and 750 degrees C). Single phase, nanocrystalline, spinel cobalt ferrite formation is confirmed by X-ray diffraction (XRD) for T(s) > or = 300 degrees C. Conventional XRD studies reveal strong (111) texturing in the as deposited films with T(s) > or = 550 degrees C. Bulk texture measurements using X-ray orientation distribution function confirmed (111) preferred orientation in the films with T(s) > or = 550 degrees C. Grain size (13-16 nm for T(s) > or = 300 degrees C) estimation using grazing incidence X-ray line broadening analysis shows insignificant grain growth with increasing T(s), which is in good agreement with grain size data obtained from transmission electron microscopy.

Role of interparticle interactions on the magnetic behavior of Mg(0.95)Mn(0.05)Fe(2)O(4) ferrite nanoparticles

We present here a detailed investigation of the static and dynamic magnetic behavior of a Mg(0.95)Mn(0.05)Fe(2)O(4) spinel ferrite nanoparticle system synthesized by high-energy ball milling of almost identical particle size distributions ([Formula: see text], 5.1 and 6.0 ± 0.6 nm). The samples were characterized by using x-ray diffraction, Mössbauer spectroscopy, dc magnetization and frequency dependent real χ(')(T) and imaginary χ('')(T) parts of ac susceptibility measurements. The zero-field-cooled (ZFC) and field-cooled (FC) magnetization have been recorded in a low field and show a behavior typical of superparamagnetic particles above a temperature of 185 ± 5 K, which is further supported from the temperature dependent Mössbauer measurements. The fact that the blocking temperature calculated from the ZFC magnetization and Mössbauer data are almost similar gives a clear indication of the interparticle interactions among these nanoparticle systems. This is further supported from the FC magnetization curves, which are almost flat below a certain temperature (less than the blocking temperature), as compared with the monotonically increasing behavior characteristics of non-interacting superparamagnetic particles. A shift of the blocking temperature with increasing frequency was observed in the real χ(')(T) and imaginary χ('')(T) parts of the ac susceptibility measurements. The analysis of the results shows that the data fit well with the Vogel-Fulcher law, whereas trials using the Neel-Brown and power law are unproductive. The role of magnetic interparticle interactions on the magnetic behavior, namely superparamagnetic relaxation time and magnetic anisotropy, are discussed.

Investigation of Ti layer thickness dependent structural, magnetic, and photoemission study of nanometer range Ti/Ni multilayer structures

Structural, magnetic, and electronic properties of Ti/Ni multilayer (ML) samples as a function of Ti layer thickness are studied and reported in this paper. For this purpose [Ti (t nm)/Ni (5 nm)] x 10 ML samples, where t = 3, 5, and 7 nm have been deposited by using electron beam evaporation technique under UHV conditions at room temperature. Structure of ML samples were determined by using XRD (X-ray diffraction) technique and observed that Titanium is deposited mainly in amorphous nature with FCC structure at lower Ti layer thickness of 3 nm, which transform to crystalline HCP structures above than this Ti layer thickness. Corresponding fitted GIXRR (grazing incidence X-ray reflectivity) patterns shows asymmetric nature of Ti-Ni and Ni-Ti interfaces because of heavy intermixing and interdiffusion of Ni and Ti atoms at Ti-Ni interfaces at lower Ti layer thickness. The depth profiling core level and valence band measurements carried out by using XPS (X-ray photoelectron spectroscopy) technique confirms the interdiffusion and intermixing leading to Ti-Ni alloy phase formation at interfaces during deposition, particularly at lower Ti layer thickness of 3 nm. The corresponding magnetization behavior of ML samples has been investigated using Magneto-Optical Kerr Effect (MOKE) technique and observed that, coercitivity decreases while saturation magnetization increases with Ti layer thickness variations. These results are interpreted and discussed in terms of observed micro-structural changes due to Ti layer thickness vitiations in Ti/Ni multilayer samples.

Furanoid sugar amino acids as dipeptide mimics in design of analogs of vasoactive intestinal peptide receptor binding inhibitor

In this study we describe the development of peptidomimetic analogs of the potent vasoactive intestinal peptide receptor binding inhibitor, Leu(1) -Met(2) -Tyr(3) -Pro(4) -Thr(5) -Tyr(6) -Leu(7) -Lys(8) -OH 1, by incorporating furanoid sugar amino acids (SAAs) 2-4 into the molecule. The furanoid SAAs 2-4 were used as dipeptide isosteres to replace Tyr(3) -Pro(4) or Pro(4) -Thr(5) in sequence 1. The resulting analogs 5-9 were tested for their anti-cancer activities in vitro, following the standard MTT assay on a panel of human cancer cell lines. One of the potent analogs, 6a was tested in vivo for tumor regression on primary colon tumor xenografted nude mice. Our experimental results suggest that many of these analogs show either retention or enhancement of biological activity.

Differences in in vitro pollen germination and pollen tube growth of cotton cultivars in response to high temperature

BACKGROUND AND AIMS

High-temperature environments with >30 degrees C during flowering reduce boll retention and yield in cotton. Therefore, identification of cotton cultivars with high-temperature tolerance would be beneficial in both current and future climates. *

METHODS

Response to temperature (10-45 degrees C at 5 degrees C intervals) of pollen germination and pollen tube growth was quantified, and their relationship to cell membrane thermostability was studied in 12 cultivars. A principal component analysis was carried out to classify the genotypes for temperature tolerance. *

KEY RESULTS

Pollen germination and pollen tube length of the cultivars ranged from 20 to 60 % and 411 to 903 microm, respectively. A modified bilinear model best described the response to temperature of pollen germination and pollen tube length. Cultivar variation existed for cardinal temperatures (T(min), T(opt) and T(max)) of pollen germination percentage and pollen tube growth. Mean cardinal temperatures calculated from the bilinear model for the 12 cultivars were 15.0, 31.8 and 43.3 degrees C for pollen germination and 11.9, 28.6 and 42.9 degrees C for pollen tube length. No significant correlations were found between pollen parameters and leaf membrane thermostability. Cultivars were classified into four groups based on principal component analysis. *

CONCLUSIONS

Based on principal component analysis, it is concluded that higher pollen germination percentages and longer pollen tubes under optimum conditions and with optimum temperatures above 32 degrees C for pollen germination would indicate tolerance to high temperature.

Interactive effects of carbon dioxide, temperature, and ultraviolet-B radiation on soybean (Glycine max L.) flower and pollen morphology, pollen production, germination, and tube lengths

Plant reproduction is highly vulnerable to global climate change components such as carbon dioxide concentration ([CO(2)]), temperature (T), and ultraviolet-B (UV-B) radiation. The objectives of this study were to determine the effects of season-long exposure to treatments of [CO(2)] at 360 (control) and 720 micromol mol(-1) (+CO(2)), temperature at 30/22 degrees C (control) and 38/30 degrees C (+T) and UV-B radiation 0 (control) and 10 kJ m(-2) d(-1) (+UV-B) on flower and pollen morphology, pollen production, germination, and tube lengths of six soybean genotypes (D 88-5320, D 90-9216, Stalwart III, PI 471938, DG 5630RR, and DP 4933RR) in sunlit, controlled environment chambers. The control treatment had 360 micromol mol(-1) [CO(2)] at 30/22 degrees C and 0 kJ UV-B. Plants grown either at +UV-B or +T, alone or in combination, produced smaller flowers with shorter standard petal and staminal column lengths. Flowers so produced had less pollen with poor pollen germination and shorter tube lengths. Pollen produced by the flowers of these plants appeared shrivelled without apertures and with disturbed exine ornamentation even at +CO(2) conditions. The damaging effects of +T and +UV-B were not ameliorated by +CO(2) conditions. Based on the total stress response index (TSRI), pooled individual component responses over all the treatments, the genotypes were classified as tolerant (DG 5630RR, D 88-5320: TSRI >-790), intermediate (D 90-9216, PI 471938: TSRI <-790 to >-1026), and sensitive (Stalwart III, DP 4933RR: TSRI <-1026). The differences in sensitivity identified among genotypes imply the options for selecting genotypes with tolerance to environmental stresses projected to occur in the future climates.

Evaluation of zinc against salinomycin toxicity in broilers

Salinomycin was studied for its toxicity and zinc (80 mg/kg) was assessed for prophylactic and therapeutic management in broiler chicks. Male broiler chicks were randomly divided into 7 groups consisting of 6 chicks in each. Group 1, 2 and 3 were maintained as control, therapeutic dose control (60 mg/kg feed) and toxic dose control (120 mg/kg feed), respectively. Group 4 was fed on feed containing salinomycin therapeutic dose and zinc. Group 5 received feed containing toxic dose of salinomycin. Group 6 and 7 were fed on feed containing toxic dose of salinomycin for the first 4 weeks for induction of ionophore toxicity and for the subsequent 2 weeks, group 6 received zinc and group 7 was fed on feed containing toxic dose of salinomycin along with zinc. Weekly body weights revealed a significant (P<0.01) decrease in toxic controls as compared to group 1, 2, 4 and 5. The activity of glutathione peroxidase, glutathione reductase and catalase, and the values of aspartate aminotransferase (AST), alanine aminotransferase (ALT), total proteins, total cholesterol, triglycerides, low density lipoproteins (LDL), urea, creatinine and blood urea nitrogen (BUN) were significantly (P<0.01) elevated in toxic controls, whereas glutathione (GSH) and high density lipoproteins (HDL) were significantly (P<0.01) lowered as compared to group 1, 2, 4 and 5. Following toxicity, zinc supplementation in group 6 and 7, all serobiochemical parameters were revived to normal. Thus, it is enunciated that salinomycin toxicity is due to oxidative damage and use of zinc in feed tends to cure and avoid any accidental toxicity.

The scientific basis for selecting surgical sutures

The purpose of this study was to examine the handling properties of synthetic absorbable and monofilament polypropylene sutures made by two different manufacturers and to compare a subjective evaluation by surgeons to the results of standardized biomechanical performance tests. The surgeons' clinical subjective evaluation of the monofilament polypropylene sutures correlated with the results of the biomechanical performance studies, whereas the biomechanical evaluation of the two synthetic absorbable sutures detected notable differences in their performance. These distinct differences in biomechanical performance of the absorbable sutures did not alter their performance in the subjective clinical evaluation.

Expression of integrin receptors on peripheral lymphocytes: correlation with endometrial receptivity

PROBLEM

To investigate the expression of integrin (ITG) cell adhesion molecules on peripheral blood lymphocytes (PBL) and their correlation with endometrial cell ITG expression in fertile and infertile women during peak uterine receptive period (day 19/20).

METHOD OF STUDY

Surface marker expression and quantification of alpha6, alpha4 and beta3 ITG subunits was done by immunohistochemistry, indirect immunofluroscence and cell-enzyme-linked immunosorbent assay methods using endometrial cells and PBL obtained from fertile and infertile (unexplained infertility) women.

RESULTS

The expression of ITGs was significantly (P<0.001) decreased in the endometrial cells of infertile women compared to normal fertile women. These results correlated well with the data obtained using PBL-ITG expression.

CONCLUSIONS

If these preliminary data are consistent in a larger group of patients, the expression of alpha4 and beta3-ITG subunits on PBL may be used as clinical markers to assess endometrial receptivity in infertile women. Moreover, frequent blood sampling is advantageous over repeated endometrial biopsies as the former approach is easier, non-traumatic and avoids intra-uterine infections.

Adolescent gingival squamous cell carcinoma: Report of a case and review of the literature

In this article we describe a case of adolescent squamous cell carcinoma of the gingiva. The tumor presented as an ulcerative lesion of the gingiva that was originally thought to be pseudoepitheliomatous hyperplasia. The pathologic differentiation between squamous cell carcinoma and pseudoepitheliomatous hyperplasia is discussed and a review of the literature with respect to pediatric and adolescent oral squamous cell carcinoma is presented. The reported case illustrates the difficulties that may be encountered in attempting to histopathologically distinguish between pseudoepitheliomatous hyperplasia and well-differentiated squamous cell carcinoma of the oral cavity.

5th Annual David R. Boyd, MD Lecture: Revolutionary advances in wound repair in emergency medicine during the last three decades. A view toward the new millennium

This lecture provides an overview of advances in wound repair devised by our multidisciplinary team of physicians, scientists, and students. Our collective efforts have devised products, drugs, and concepts that are facilitating wound repair without infection and with the least possible scar. Some of the beneficial products and drugs developed or identified by our laboratory include nitrile examination and surgical gloves, magnification loupes, high pressure syringe irrigation, Shur Clens, as well as a wide variety of different wound closure techniques. In addition, our studies of the mechanism of wound injury, soil infection-potentiating fractions, dynamic and static skin tensions, and microflora of the skin have become important predictors of the outcomes of wound repair. During the new millennium, the computerized clinical information system as well as studies of tissue regeneration should dramatically change our approaches to wound repair.

Use of CC traps with different trap base colors for silverleaf whiteflies (Homoptera: Aleyrodidae), thrips (Thysanoptera: Thripidae), and leafhoppers (Homoptera: Cicadellidae)

During 1996, 1997, and 1999, studies were conducted in cotton, sugar beets, alfalfa, yardlong bean, and peanut fields to compare insect catches in CC traps equipped with different trap base colors. The studies were conducted in southwestern United States, China, and India. The nine colors, white, rum, red, yellow, lime green, spring green, woodland green (dark green), true blue, and black, varied in spectral reflectance in the visible (400-700 nm) and near-infrared (700-1050 nm) portions of spectrum. Lime green, yellow, and spring green were the three most attractive trap base colors for silverleaf whitefly, Bemisia argentifolii Bellows & Perring, and leafhopper, Empoasca spp. adults. The three trap base colors were moderately high in the green, yellow, and orange spectral regions (490-600 nm), resembling the spectral reflectance curve of the abaxial (underleaf) surfaces of green cotton leaves. True blue and white were the most attractive trap base colors for western flower thrips, Frankliniella occidentalis (Pergande), adults. The true blue and white trap bases were moderately high in the blue spectral region (400-480 nm).

Biomechanical performance of latex and non-latex double-glove systems

The purpose of this study was to evaluate ten commercially available latex, powder-free surgical gloves and four commercially available non-latex, powder-free surgical gloves using standardized, reproducible biomechanical parameters that included glove thickness, puncture resistance, and glove donning force. For all gloves tested, with one exception (Neolontrade mark PF), puncture resistance increased for double-gloves as compared to single-gloves. In addition, single-glove thickness was not a reliable determinant of puncture resistance for either latex or non-latex gloves. For the latex gloves, the Ultrafree double and single-gloves exhibited the highest puncture resistance. The glove donning forces for the Biogeltrade mark M and Biogel Sensortrade mark single-gloves were the lowest. In contrast, the Biogel Revealtrade mark and Encoretrade mark Ultra-Thick exhibited the lowest double-glove donning forces. On the basis of these performance tests of latex gloves, the surgeon should consider the Biogel Reveal as well as the Ultrafree gloves for their latex double-glove system. For the non-latex gloves, the Pure Advantage Nitriletrade mark glove had the highest puncture resistance for one layer and two layers of glove material. The thin Pure Advantage Nitrile glove was the most resistant to glove puncture. The Pure Advantage Nitrile glove had low glove donning forces for both single-glove donning configurations and double-glove donning configurations. Consequently, we recommend the Pure Advantage Nitrile glove as the powder-free, non-latex, double-glove system.

Evaluation of the antifertility effect of magainin-A in rabbits: in vitro and in vivo studies

OBJECTIVE

To evaluate the safety and contraceptive potential of magainin-A in rabbits.

DESIGN

Controlled laboratory study.

SETTING

Department of Immunology, Institute for Research in Reproduction, Mumbai, Parel, India.

ANIMAL(S)

Forty-eight female New Zealand white rabbits.

INTERVENTION(S)

The effect of magainin-A on sperm motility (in vitro and in vivo studies) and on vaginal epithelium (histologic study) was assessed along with serum and liver biochemical profiles.

MAIN OUTCOME MEASURE(S)

Suitability of magainin-A for contraceptive use.

RESULT(S)

Magainin-A arrested sperm motility, and 1 mg of magainin-A administered intravaginally blocked conception. No histopathologic abnormalities in the vaginal tissue or any changes in serum biochemical profiles were observed.

CONCLUSION(S)

Magainin-A may be used as an effective and safe intravaginal contraceptive compound that also has antibacterial properties.

Biomechanical performance of powder-free examination gloves

Biomechanical performance studies were undertaken for powder-free, latex and nitrile examination gloves. Using standardized tests, examination glove performance was judged by measuring glove thickness, glove puncture force, glove tape adhesion force, glove donning force, glove stiffness, and immediate unrecovered stretch. Even though the nitrile examination gloves were thinner than the latex examination gloves, they exhibited a greater puncture resistance. In addition, tape adherence to the N-Dex nitrile glove was the lowest. Moreover, measurements of the handling characteristics of the nitrile examination gloves demonstrated that they are an acceptable alternative to latex examination gloves. While these biomechanical studies demonstrate the superiority of the nitrile examination gloves, clinical glove evaluation is still needed to determine their performance in the health care setting.

The scientific basis of surgical glove selection in an in vitro fertilization laboratory

Mouse embryos and human sperm are used as quality control bioassays in human in vitro fertilization (IVF) laboratories. These two models can reveal the cytotoxicty of items commonly used in IVF, such as surgical gloves. The literature published in this area points to the cytotoxicity of both glove powders and glove products.

Utilisation of squilla meal (a novel animal protein source) by broilers

1. The nutritive value of squilla meal, which contained 339 g crude protein, 18.6 g ether extract, 72.8 g calcium, 17.2 g phosphorus and 7.13 MJ of apparent metabolisable energy/kg, was examined in 5 experiments with broilers. 2. Squilla meal contained less lysine (3.45 vs 6.74 g/16g nitrogen) and methionine (1.02 vs 1.86/16 g nitrogen) than fish meal, had a lower protein digestibility coefficient (0.66 vs 0.72) and a lower gross protein value (68% vs 74%). 3. By gradually replacing the fish meal with squilla meal in isocaloric, isonitrogenous broiler diets it was shown that there was a linear decrease in broiler weight gain; efficiencies of food utilisation were also lower at all squilla meal substitution rates. Inclusion of squilla meal in the diets increased intestinal lengths. 4. Addition of a proteolytic enzyme to the diets containing squilla meal restored broiler weight gain and efficiency of food utilisation to that of birds fed on the control diet. 5. Diets containing autoclaved squilla meal resulted in reduced weight gain although efficiency of food utilisation was not affected.

Comparison of formalin preserved bone allograft in the form of a paste and as bone chips in fresh femoral shaft fractures with comminution

Femoral shaft fractures with comminution are indicators for primary bone grafting. Problems related to autograft use have led us to evolve methods using allografts preserved in formalin. This method is cheap, easy, reliable and is readily available in the poorer countries. Comparison of 20 cases using allograft paste with 20 cases using allograft chips slivers in similar femoral shaft fractures was done. In both cases, the fusion time was slightly delayed as compared to cases using autograft. The infection rates were comparable, but it was noticed that bone paste got resorbed in 2 cases, leading to plate bending and malunion. The theoretical advantage of the bone paste in filling up the defects and crevices in the comminuted fractures was offset by the practical disadvantage of having no osteoconductive scaffolding, which was provided by the bone chips. It is thus recommended that formalin preserved bone allograft paste may be better suited for use in bony cavities and joint replacements, while formalin preserved bone chips are a good alternative to bone autografts, especially in polytrauma cases. Formalin preserved allografts are a viable alternative method for use in third world countries.

Utilisation of pearl millet (Pennisetum typhoides) for egg production

1. The performance of White Leghorn laying hens on diets providing pearl millet (Pennisetum typhoides) at 300 and 600 g/kg to replace maize, part per part, or "maize mix" isoenergetically and isonitrogenously in the first experiment and at 600 g/kg diet to replace maize in toto, part per part, in the second experiment were examined. In the first experiment, 3 groups of 12 laying hens were placed on each of the 5 dietary treatments for 3 x 28 d, whereas in the second experiment, each of the two diets was offered to 10 groups of 15 laying hens for 6 x 28 d. 2. Inclusion of pearl millet in the diet at the expense of maize, part per part, did not significantly influence hen-day egg production, feed intake, feed efficiency and body weight in either experiment. Incorporation of pearl millet isoenergetically at the expense of "maize mix" at any level, i.e. 300 g or 600 g/kg (Experiment 1), also did not influence hen-day egg production but at the end of periods 2 and 3 did result in decreased feed intakes with consequent improvements in feed efficiency. 3. Egg weight in general showed a tendency to improve with diets providing pearl millet at 600 g/kg. 4. Profits from egg sales over feed cost were directly proportional to the inclusion of pearl millet in the diet either at the expense of maize, part per part, or "maize mix" isoenergetically.

Extraction and isolation by high performance liquid chromatography of uroporphyrin and coproporphyrin isomers from biological tissues

A simple, rapid procedure has been developed for extraction of uroporphyrin and coproporphyrin isomers from biological tissues. The recoveries of known standards of uroporphyrin I and III and coproporphyrin I and III were performed from liver, kidney, testis, and bone marrow of the rat. The extracted samples were analyzed by high performance liquid chromatography. This method is suitable for the study of drug- and toxicant-induced porphyrias characterized by alterations of the ratios of the I and III isomers of uroporphyrin and coproporphyrin.

Depression of rat testicular 17-hydroxylase and 17,20-lyase after administration of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)

Toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), such as chloracne, hirsutism, and skin hyperpigmentation, suggest endocrine involvement, however, little is known about the effects of TCDD on steroidogenic organs. It is known that TCDD can cause decreases in testicular heme, testicular microsomal cytochrome P-450, and serum testosterone in the rat. This study was designed to examine the activities of the testicular hemoprotein microsomal cytochrome P-450-dependent enzymes, 17-hydroxylase and 17,20-lyase, following a single, oral dose of either 12.5, 25, or 50 micrograms/kg TCDD. TCDD caused dose- and time-dependent decreases in the activity of the 17-hydroxylase enzyme. Significant decreases were observed at 3, 7 and 14 days at the lowest dose of 12.5 micrograms/kg TCDD. The 17,20-lyase enzyme seemed to be less sensitive to the toxic effects of TCDD with significant decreases in enzyme activity being observed at days 3, 7 and 14 only after treatment with 50 micrograms/kg TCDD. Both microsomal cytochrome P-450 and serum testosterone levels decreased in a dose- and time-dependent manner following 12.5, 25 and 50 micrograms/kg doses of TCDD. These results indicate that decreased testosterone production following treatment with TCDD is related to decreased activities of the testicular microsomal cytochrome P-450-dependent enzymes 17-hydroxylase and 17,20-lyase.

Increased rat testicular heme oxygenase activity associated with depressed microsomal heme and cytochrome P-450 levels after repeated administration of human chorionic gonadotropin

Repeated administration of human chorionic gonadotropin to rats results in a maximal depression of testicular microsomal heme and cytochrome P-450 levels at 24 h, followed by increases that plateau at pretreatment levels by day six. Associated with the depressed levels of microsomal heme and cytochrome P-450 is an increase of testicular microsomal heme oxygenase activity at 12-24 h. Testicular mitochondrial delta-aminolevulinic acid synthase activity was increased at 24 h, and remained elevated throughout the 9-day treatment period. Pretreatment with 1,4,6-androstatrien-3,17-dione, an aromatase inhibitor, failed to prevent the depression of testicular microsomal heme or cytochrome P-450 or increased heme oxygenase activity caused by repeated administration of human chorionic gonadotropin, and administration of estradiol benzoate failed to alter testicular microsomal heme oxygenase activity suggesting that these parameters were not related to altered testicular estrogen content caused by increased aromatase activity. These results suggest that increased testicular heme oxygenase activity is associated with decreased microsomal heme and cytochrome P-450 content during human chorionic gonadotropin-induced desensitization.

Reversal of sulfamerazine inhibition of rat hepatic uroporphyrinogen synthesis by folic acid

The ability of rat hepatic uroporphyrinogen cosynthase to direct formation of uroporphyrinogen III and the synthesis of uroporphyrinogen in vitro was impaired by sulfamerazine. Inhibition was reversed by the addition of folic acid. Administration of a single, oral dose (1 g/kg) of sulfamerazine to rats was associated with elevated levels of hepatic uroporphyrin I isomer. These results suggest that sulfonamides may interfere with the biosynthesis of uroporphyrinogen III.

Calcium and phosphorus requirements of growing Japanese quail

1. Calcium and phosphorus requirements of growing female Japanese quail during 4 and 5 weeks of age were estimated in a 4 x 3 factorial experiment comprising 5, 7, 9 and 11 g calcium and 5, 6 and 7 g phosphorus/kg diet. 2. Responses in weight gain, bone ash, food intake and food : gain ratio showed no significant differences due to varying dietary calcium and phosphorus concentrations. 3. It appears that growing Japanese quail require not more than 5 g calcium and not more than 5 g phosphorus (2 g available phosphorus)/kg diet (398 mg calcium and 398 mg phosphorus or 159 mg available phosphorus MJ ME).

Effects of parental consanguinity on fertility, mortality and morbidity among the Pattusalis of Tirupati, South Indian

The incidence of consanguineous marriages is very high in the Pattusali population. First cousin marriages are preferred mostly. The consanguinity effects obtained in this population are also mostly confined to these marriages only. The inbreeding coefficient for the population is 0.02997. The consanguinity on fertility, mortality and morbidity are discussed in the paper.