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1.  A preliminary report on the distribution of lizards in Qatar 
ZooKeys  2014;67-91.
We have updated the list of the lizard species present in Qatar and produced the first distribution maps based on two field surveys in 2012 and 2013. We used the QND95/Qatar National Grid with a grid of 10 × 10 km squares for mapping. Our results show the occurrence of 21 lizard species in Qatar, from the 15 species indicated in the last biodiversity report conducted in 2004. The most abundant family found in Qatar is Gekkonidae with nine species (Bunopus tuberculatus, Cyrtopodion scabrum, Hemidactylus robustus, H. flaviviridis, H. persicus, Stenodactylus arabicus, S. slevini, S. doriae, Pseudoceramodactylus khobarensis), followed by Lacertidae with four species (Acanthodactylus schmidti, A. opheodurus, Mesalina brevirostris, M. adramitana), Agamidae with three species (Trapelus flavimaculatus, Uromastyx aegyptia, Phrynocephalus arabicus), Scincidae with two species (Scincus mitranus, Trachylepis septemtaeniata), and Varanidae (Varanus griseus), Sphaerodactylidae (Pristurus rupestris) and Trogonophiidae (Diplometopon zarudnyi) with one species each. The species richness fluctuated largely across Qatar between one and eleven species per grid square. We believe that the lizard fauna records in Qatar are still incomplete and that additional studies are required. However, our study here fills a gap concerning lizard biodiversity knowledge in the Gulf Region.
PMCID: PMC3909808  PMID: 24493961
Reptilia; geographic distribution; species richness; inventory; maps; biodiversity; atlas
2.  "Reticular" and "Areticular" Nissl Bodies in Sympathetic Neurons of a Lizard 
Sympathetic ganglia of the horned lizard, Phrynosoma cornutum, were fixed in OsO4 and imbedded in methacrylate. Thin sections were cut for electron microscopy. Some adjacent thick sections were cut for light microscopy and were stained in acidified, dilute thionine both before and after digestion by RNase. In the light microscope two types of Nissl bodies are found, both removable by RNase: (1) a deep, diffuse, indistinctly bounded, metachromatic variety, and (2) a superficial, dense, sharply delimited, orthochromatic sort. Electron microscopically, the former ("reticular" Nissl bodies) corresponds to the granulated endoplasmic reticular structure of Nissl material previously described by others, whereas the latter ("areticular" Nissl bodies) comprises compact masses of particles of varying internal density and devoid of elements of endoplasmic reticulum. The constituent particles of the areticular Nissl material are 4 to 8 x the diameter of single ribonucleoprotein granules of the reticular Nissl substance and seem, near zones of junction with the reticular type, to arise by clustering of such granules with subsequent partial dispersion of the substance of the granules into an added, less dense material. It is suggested that the observed orthochromasia of the areticular Nissl substance is due to accumulation of a large amount of protein bound to RNA and, further, that these Nissl bodies may represent storage depots of RNA and protein.
PMCID: PMC2229759  PMID: 13673051
3.  Effects of Frugivore Preferences and Habitat Heterogeneity on Seed Rain: A Multi-Scale Analysis 
PLoS ONE  2012;7(3):e33246.
Seed rain mediated by frugivores is influenced by (1) the seed-deposition distances following fruit ingestion, (2) the disperser activity, as determined by its behaviour and habitat preferences, and (3) the structure of the habitat within the landscape. Here, we evaluated such components using the fleshy-fruited shrub Ephedra fragilis and the frugivorous Balearic lizard Podarcis lilfordi. We estimated seed-deposition patterns based on the displacements and habitat preferences of lizards, derived from visual surveys and telemetry data. The influence of variables potentially determining lizard habitat preference (i.e., height, slope, four measures of habitat abundance and four measures of habitat fragmentation) was evaluated at three spatial scales: ‘home-range’ (c. 2.5–10*103 m2; telemetry data), ‘within home-range’ (c. 100 m2; telemetry data) and ‘microhabitat’ (<100 m2; visual survey). Cumulative lizard displacement (from each telemetric location to the initial capture point) saturated before the peak of seed defecation (seed-retention time), indicating that lizard home-range size and habitat preferences were the main determinants of the spread and shape of seed shadows. Shrub cover was positively correlated with habitat preference at the three scales of analysis, whereas slope was negatively correlated at the home-range scale. Model scenarios indicated that spatially-aggregated seed rain emerged when we incorporated the joint effect of habitat preference at the two largest (home-range and within home-range) scales. We conclude that, in order to predict seed rain in animal dispersed plants, it is important to consider the multi-scale effects of habitat preference by frugivores.
PMCID: PMC3306386  PMID: 22438902
4.  Thermal porosity analysis of croscarmellose sodium and sodium starch glycolate by differential scanning calorimetry 
AAPS PharmSciTech  2003;4(4):531-538.
The aim of the study was to demonstrate the applicability of differential scanning calorimetry (DSC) on porosity analysis for cellulose and starch. Croscarmellose sodium (CCS) and sodium starch glycolate (SSG) were allowed to sorb moisture in 85%, 90%, 95%, and 100% relative humidity (RH) at 40°C for 24 hours. The pretreated samples were then subjected to DSC running temperature ranging from 25°C to −50°C at a cooling rate of 10°C/min. The cooling traces of water crystallization, if present, were transformed to porosity distribution via capillary condensation using Kelvin's equation. The porosity analysis of CCS and SSG was also done using nitrogen adsorption as a reference method. It was found that sorbed water could not be frozen (in cases of 85% and 90% RH) until the moisture content exceeded a cutoff value (in cases of 95% and 100% RH). The nonfreezable moisture content was referred to tightly bound, plasticizing water, whereas the frozen one may be attributed to loosely bound water condensation in pore structure of CCS and SSG surfaces. Not only capillary condensation but also the tightly bound, nonfreezable monolayer water lying along the inner pores of the surface contributed to porosity determination. Good agreement with less than 5% deviation of mean pore size was observed when the results were compared with nitrogen adsorption. The narrower pore size distributions, however, were obtained because of the limitations of the technique. It was concluded that pore analysis by DSC could be successful. Further research needs to be done to account for limitations and to extend the applicability of the technique.
PMCID: PMC2750660  PMID: 15198562
thermoporometry; differential scanning calorimetry (DSC); croscarmellose sodium (CCS); sodium starch glycolate (SSG)
5.  Foliar water uptake: a common water acquisition strategy for plants of the redwood forest 
Oecologia  2009;161(3):449-459.
Evaluations of plant water use in ecosystems around the world reveal a shared capacity by many different species to absorb rain, dew, or fog water directly into their leaves or plant crowns. This mode of water uptake provides an important water subsidy that relieves foliar water stress. Our study provides the first comparative evaluation of foliar uptake capacity among the dominant plant taxa from the coast redwood ecosystem of California where crown-wetting events by summertime fog frequently occur during an otherwise drought-prone season. Previous research demonstrated that the dominant overstory tree species, Sequoia sempervirens, takes up fog water by both its roots (via drip from the crown to the soil) and directly through its leaf surfaces. The present study adds to these early findings and shows that 80% of the dominant species from the redwood forest exhibit this foliar uptake water acquisition strategy. The plants studied include canopy trees, understory ferns, and shrubs. Our results also show that foliar uptake provides direct hydration to leaves, increasing leaf water content by 2–11%. In addition, 60% of redwood forest species investigated demonstrate nocturnal stomatal conductance to water vapor. Such findings indicate that even species unable to absorb water directly into their foliage may still receive indirect benefits from nocturnal leaf wetting through suppressed transpiration. For these species, leaf-wetting events enhance the efficacy of nighttime re-equilibration with available soil water and therefore also increase pre-dawn leaf water potentials.
PMCID: PMC2727584  PMID: 19585154
Leaf wetness; Water absorption; Nocturnal conductance; Stable isotopes; Deuterium
6.  Effect of Sorbed Water on Disintegrant Performance of Four Brands of Polacrilin Potassium NF 
AAPS PharmSciTech  2011;13(1):24-34.
Polacrilin Potassium NF is a commonly used weak cation exchange resin disintegrant in pharmaceutical tablets. The objective of this research was to evaluate the effects of sorbed moisture on physical characteristics and disintegrant performance of four brands of Polacrilin Potassium NF. The disintegrants were stored in five different relative humidity chambers and their dynamic vapor adsorption–desorption analysis, effect of moisture on their compressibility, compactability, particle size, morphology, water uptake rate, and disintegration ability were studied. Moisture seemed to plasticize the disintegrants, reducing their yield pressures. However, certain optimum amount of moisture was found to be useful in increasing the compactablity of the tablets containing disintegrants. The tablets, however, lost their tensile strengths beyond this optimum moisture content. Moisture caused two brands of the disintegrants to swell; however, two other brands aggregated upon exposure to moisture. Swelling without aggregation increased the water uptake, and in turn the disintegrant performance. However, aggregation probably reduced the porosities of the disintegrants, reducing their water uptake rate and disintegrant performance. Different brands of Polacrilin Potassium NF differed in the abilities to withstand the effects of moisture on their functionality. Effect of moisture on disintegrant performance of Polacrilin Potassium NF needs to be considered before its use in tablets made by wet granulation.
PMCID: PMC3299451  PMID: 22068291
disintegrant performance; effect of moisture; functionality; ion exchange resins; physical characterization; polacrilin potassium NF; sorbed water; tablet disintegrants
7.  Ultraviolet light-induced water-droplet formation from wet ambient air 
We report the formation of water droplets by irradiating wet ambient air with deep UV light. The light sources were either a continuous low-pressure mercury lamp or pulsed ArF laser, which both emit light shorter than 200 nm. Water droplets were produced in reaction vessels under different temperature, relative humidity, and moisture-supply conditions. The particles grew as large as about 0.2 mm. The suggested mechanism is discussed with the photo-dissociations of oxygen and successively formed ozone, and further dark reactions giving hydrogen peroxide as a seeding nucleus. Observed concentrations of intermediates were well explained by simulating the proposed chemical reactions. A possible application to artificial rain is briefly described.
PMCID: PMC3859366  PMID: 24367154
water droplet formation; wet air; photochemical seeding; ultraviolet light; nucleation of water; hydrogen peroxide
8.  An examination of the moisture sorption characteristics of commercial magnesium stearate 
AAPS PharmSciTech  2001;2(4):73-79.
The objective of this study was to characterize the moisture sorption of magnesium stearate and the morphological changes, if any, resulting from moisture sorption. Six samples of commercial magnesium stearate USP were examined. Moisture sorption isotherms were obtained at 25°C and 5% to 98% relative humidity (RH) using a moisture balance. Changes in crystal form resulting from moisture sorption were determined by x-ray diffraction. There were differences in the shape of the isotherm, reversibility of moisture uptake, and shape of the hysteresis loop in the isotherms of crystalline and amorphous magnesium stearates. The isotherm of crystalline magnesium stearate was almost parallel to the pressure axis until and RH of ∼80%. The isotherm of the amorphous sample was characterized by continuous uptake of water over the entire range of RH. Exposure of amorphous magnesium stearate to RH greater than 70% resulted in the formation of the trihydrate. The trihydrate was converted into the anhydrous form when heated to a temperature of 100°C to 105°C. The trihydrate could be generated by exposing the anhydrate to RH higher than 70%.
PMCID: PMC2784843
Moisture sorption; magnesium stearate hydrates; crystalline; amorphous magnesium stearate
9.  Evaluating Humidity Recovery Efficiency of Currently Available Heat and Moisture Exchangers: A Respiratory System Model Study 
Clinics (Sao Paulo, Brazil)  2009;64(6):585-590.
To evaluate and compare the efficiency of humidification in available heat and moisture exchanger models under conditions of varying tidal volume, respiratory rate, and flow rate.
Inspired gases are routinely preconditioned by heat and moisture exchangers to provide a heat and water content similar to that provided normally by the nose and upper airways. The absolute humidity of air retrieved from and returned to the ventilated patient is an important measurable outcome of the heat and moisture exchangers’ humidifying performance.
Eight different heat and moisture exchangers were studied using a respiratory system analog. The system included a heated chamber (acrylic glass, maintained at 37°C), a preserved swine lung, a hygrometer, circuitry and a ventilator. Humidity and temperature levels were measured using eight distinct interposed heat and moisture exchangers given different tidal volumes, respiratory frequencies and flow-rate conditions. Recovery of absolute humidity (%RAH) was calculated for each setting.
Increasing tidal volumes led to a reduction in %RAH for all heat and moisture exchangers while no significant effect was demonstrated in the context of varying respiratory rate or inspiratory flow.
Our data indicate that heat and moisture exchangers are more efficient when used with low tidal volume ventilation. The roles of flow and respiratory rate were of lesser importance, suggesting that their adjustment has a less significant effect on the performance of heat and moisture exchangers.
PMCID: PMC2705149  PMID: 19578664
Heat and moisture exchangers; Humidity; Temperature; Mechanical ventilation
10.  The effect of moisture absorption on the physical properties of polyurethane shape memory polymer foams 
Smart materials & structures  2011;20(8):085010.
The effect of moisture absorption on the glass transition temperature (Tg) and stress/strain behavior of network polyurethane shape memory polymer (SMP) foams has been investigated. With our ultimate goal of engineering polyurethane SMP foams for use in blood contacting environments, we have investigated the effects of moisture exposure on the physical properties of polyurethane foams. To our best knowledge, this study is the first to investigate the effects of moisture absorption at varying humidity levels (non-immersion and immersion) on the physical properties of polyurethane SMP foams. The SMP foams were exposed to differing humidity levels for varying lengths of time, and they exhibited a maximum water uptake of 8.0% (by mass) after exposure to 100% relative humidity for 96 h. Differential scanning calorimetry results demonstrated that water absorption significantly decreased the Tg of the foam, with a maximum water uptake shifting the Tg from 67 °C to 5 °C. Samples that were immersed in water for 96 h and immediately subjected to tensile testing exhibited 100% increases in failure strains and 500% decreases in failure stresses; however, in all cases of time and humidity exposure, the plasticization effect was reversible upon placing moisture-saturated samples in 40% humidity environments for 24 h.
PMCID: PMC3176498  PMID: 21949469
11.  Consequences of exclusion of precipitation on microorganisms and microbial consumers in montane tropical rainforests 
Oecologia  2012;170(4):1067-1076.
The structure and functioning of decomposer systems heavily relies on soil moisture. However, this has been primarily studied in temperate ecosystems; little is known about how soil moisture affects the microfaunal food web in tropical regions. This lack of knowledge is surprising, since the microfaunal food web controls major ecosystem processes. To evaluate the role of precipitation in the structure of soil food web components (i.e., microorganisms and testate amoebae), we excluded water input by rain in montane rainforests at different altitudes in Ecuador. Rain exclusion strongly reduced microbial biomass and respiration by about 50 %, and fungal biomass by 23 %. In testate amoebae, rain exclusion decreased the density of live cells by 91 % and caused a shift in species composition at each of the altitudes studied, with ergosterol concentrations, microbial biomass, and water content explaining 25 % of the variation in species data. The results document that reduced precipitation negatively affects soil microorganisms, but that the response of testate amoebae markedly exceeds that of bacteria and fungi. This suggests that, in addition to food, low precipitation directly affects the community structure of testate amoebae, with the effect being more pronounced at lower altitudes. Overall, the results show that microorganisms and testate amoebae rapidly respond to a reduction in precipitation, with testate amoebae—representatives of higher trophic levels—being more sensitive. The results imply that precipitation and soil moisture in tropical rainforests are the main factors regulating decomposition and nutrient turnover.
Electronic supplementary material
The online version of this article (doi:10.1007/s00442-012-2360-6) contains supplementary material, which is available to authorized users.
PMCID: PMC3496542  PMID: 22614263
Rain exclusion; Testate amoebae; Ergosterol; Microbial biomass; Food web
12.  The influence of humidity on the attachment ability of the spider Philodromus dispar (Araneae, Philodromidae) 
Hairy attachment devices that are not supplemented with fluid secretion have evolved independently in lizards and spiders. van der Waals forces have previously been shown to be responsible for excellent adhesive properties of these structures, but it has recently been reported that wetting phenomena also play an important role in such ‘dry adhesives’. To investigate the effect of ambient humidity on the attachment of the living spider Philodromus dispar, traction force was measured on a smooth epoxy resin surface at relative humidities (RHs) of 15, 50, 70, 80 and 99 per cent. The results show that attachment ability is significantly higher at an intermediate humidity compared with that in a dry atmosphere and at high humidity. Water condensation on the substrate surface almost completely abolishes adhesion. Experimental results obtained may be explained by an increase in capillarity or changes in mechanical properties of setae and spatulae owing to water absorption by the cuticle at an intermediate RH. The results obtained show dry adhesion limits under different environmental conditions and are important for understanding spider biology.
PMCID: PMC3223641  PMID: 21593034
attachment; adhesion; friction; cuticle; microstructure; Arthropoda
13.  Hydrophobic constituents and their potential anticancer activities from Devil’s Club Oplopanax horridus 
Journal of ethnopharmacology  2010;132(1):280-285.
Ethnopharmacological relevance
Devil’s Club Oplopanax horridus (Sm.) Miq. is a widely used folk medicine in the Pacific Northwest such as Alaska and British Columbia for treating a variety of ailments including arthritis, cold, fever, infections, diabetes and cancer.
Aim of the study
To investigate hydrophobic constituents and their potential anticancer activity from Devil’s Club O. horridus.
Materials and methods
The root bark of O. horridus (Sm.) Miq was isolated by chromatographic techniques. Structures of isolated compounds were identified by spectroscopic methods and comparison with published data. The anti-proliferation of isolated hydrophobic constituents in human breast cancer MCF-7 cells, human colon cancer SW-480 and HCT-116 cells were tested. The potential mechanism of anti-proliferation was also investigated using cell cycle and apoptosis assays.
Results and discussion
Six compounds were isolated and structurally identified as 9,17-octadecadiene-12,14-diyne-1,11,16-triol, 1-acetate (1), oplopandiol acetate (2), falcarindiol (3), oplopandiol (4), trans-nerolidol (5) and t-cadinol (6). These compounds showed potential anticancer activities on human breast cancer and colon cancer cells, of which compound 3 possesses the strongest activity. Further cell cycle and apoptosis test by flow cytometry showed the polyacetylenes 1–4 induced HCT-116 cell arresting in G2/M phase and inhibited proliferation by the induction of apoptosis at both earlier and later stage.
These results provide promising baseline information for the potential use of O. horridus as well as some of the isolated compounds in the treatment of cancer.
PMCID: PMC3050531  PMID: 20723598
Devil’s Club Oplopanax horridus; Hydrophobic constituents; Anticancer activities; Apoptosis; Colon HCT-116 cells; Falcarindiol
14.  A new device for 100 per cent humidification of inspired air 
Critical Care  2000;4(1):54-60.
A new humidifier for use during mechanical ventilation in endotracheally intubated patients is described and tested. The humidifier is based on a heat-moisture exchanger, which absorbs the expired heat and moisture and releases it into the inspired air. External heat and water are then added at the patient side of the heat-moisture exchanger, so that the inspired gas should reach 100% humidity (44 mg/l) at 37°C. In bench tests using constant and decelerating inspiratory flow and minute volumes of 3–25 l the device gave an absolute humidity of 41–44 mg/l, and it reduced the amount of water consumed in eight mechanically ventilated patients compared with a conventional active humidifier. During a 24-h test period there was no water condensation in the ventilator tubing with the new device.
Devices for active humidification of the inspired air in mechanically ventilated patients cause water condensation in the ventilator tubing, which may become contaminated or interfere with the function of the ventilator. The present study describes and tests the performance of a new humidifier, which is designed to eliminate water condensation.
To test the performance of the new humidifier at different ventilator settings in a lung model, and to compare this new humidifier with a conventional active humidifier in ventilator-treated critically ill patients.
Materials and methods:
The humidifier (Humid-Heat; Louis Gibeck AB, Upplands Väsby, Sweden) consists of a supply unit with a microprocessor and a water pump, and a humidification device, which is placed between the Y-piece and the endotracheal tube. The humidification device is based on a hygroscopic heat-moisture exchanger (HME), which absorbs the expired heat and moisture and releases it into the inspired gas. External heat and water are then added to the patient side of the HME, so the inspired gas should reach 100% humidity at 37°C (44 mg H2O/l air). The external water is delivered to the humidification device via a pump onto a wick and then evaporated into the inspired air by an electrical heater. The microprocessor controls the water pump and the heater by an algorithm using the minute ventilation (which is fed into the microprocessor) and the airway temperature measured by a sensor mounted in the flex-tube on the patient side of the humidification device.
The performance characteristics were tested in a lung model ventilated with a constant flow (inspiratory:expiratory ratio 1:2, rate 12–20 breaths/min and a minute ventilation of 3–25 l/min) or with a decelerating flow (inspiratory:expiratory ratio 1:2, rate 12–15 breaths/min and a minute ventilation of 4.7–16.4 l/min). The device was also tested prospectively and in a randomized order compared with a conventional active humidifier (Fisher & Paykel MR730, Auckland, New Zealand) in eight mechanically ventilated, endotracheally intubated patients in the intensive care unit. The test period with each device was 24 h. The amount of fluid consumed and the amount of water in the water traps were measured. The number of times that the water traps were emptied, changes of machine filters, the suctions and quality of secretions, nebulizations, and the amount of saline instillations and endotracheal tube obstruction were recorded. In order to evaluate increased expiratory resistance due to the device, the airway pressure was measured at the end of a prolonged end-expiratory pause at 1 h of use and at the end of the test, and was compared with the corresponding pressure before the experiment. The body temperature of the patient was measured before and after the test of each device.
Both with constant flow and decelerating flow, the Humid-Heat gave an absolute humidity of 41–44 mgH2O/l at 37°C, with the lower level at the highest ventilation. In the patients, both Humid-Heat and the conventional active humidifier (MR730) maintained temperatures, indicating that they provided the intended heat and moisture to the inspired air. With both devices, the body temperature was maintained during the test period. There was no difference in the amount of secretions, the quality of the secretions and the frequency of suctions, saline instillations or nebulizations between the test periods with the two devices. There was no endotracheal tube obstruction, and after 1 h of use and at the end of the test no increased airway resistance was found with either device. When the MR730 was used, however, the water traps needed to be emptied six to 14 (mean eight) times (total amount of fluid in the traps was 100–300 ml) and the machine filters were changed two to six (mean four) times due to an excessive amount of condensed water with flow obstruction. No condensation of water was found in the tubing with the Humid-Heat. The water consumption was 23–65 ml/h (mean 30 ml/h) with the MR730 and 4–8 ml/h (mean 6 ml/h) with the Humid-Heat (P < 0.0008). The same relations were found when the water consumption was corrected for differences in minute ventilation.
The new humidifier, the Humid-Heat, gave an absolute humidity of 41–44 mg/l at 37°C in the bench tests. The tests in ventilated patients showed that the device was well tolerated and that condensation in the tubing was eliminated. There was no need to empty water traps. The test period was too short to evaluate whether the new device had any other advantages or disadvantages compared with conventional humidifiers.
PMCID: PMC29037  PMID: 11056746
airway humidification; heated humidifier; intensive care; mechanical ventilation
15.  Borrelia lusitaniae and Green Lizards (Lacerta viridis), Karst Region, Slovakia 
Emerging Infectious Diseases  2006;12(12):1895-1901.
TOC summary line: The green lizard is implicated in the transmission cycle of B. lusitaniae.
In Europe, spirochetes within the Borrelia burgdorferi sensu lato complex are transmitted by Ixodes ricinus ticks. Specific associations are described between reservoir hosts and individual genospecies. We focused on green lizard (Lacerta viridis) as a host for ticks and potential host for borreliae. In 2004 and 2005, a total of 146 green lizards infested by ticks were captured, and 469 I. ricinus ticks were removed. Borrelial infection was detected in 16.6% of ticks from lizards. Of 102 skin biopsy specimens collected from lizards, 18.6% tested positive. The most frequently detected genospecies was B. lusitaniae (77.9%–94.7%). More than 19% of questing I. ricinus collected in areas where lizards were sampled tested positive for borreliae. B. garinii was the dominant species, and B. lusitaniae represented 11.1%. The presence of B. lusitaniae in skin biopsy specimens and in ticks that had fed on green lizards implicates this species in the transmission cycle of B. lusitaniae.
PMCID: PMC3291370  PMID: 17326941
Borrelia lusitaniae; Lacerta viridis; green lizard; Ixodes ricinus; Slovakia; lyme borreliosis; Karst; research
16.  Microbiological Aspects of Ethylene Oxide Sterilization 
Applied Microbiology  1970;19(1):157-162.
An investigation determined the effects of environmental moisture content or water activity (Aw), exposure humidity, and sterilant concentration on the resistance of microbial spores. Decimal reduction values [expressed as D values at 54.4 C-specified concentration (milligrams per liter) of ethylene oxide] were determined from spore destruction curves of Bacillus subtilis var. niger dried on hygroscopic and nonhygroscopic surfaces. Four groups of spore preparations were preconditioned in one of four Aw environments (<0.1, 0.1, 0.5, 0.95) for 2 weeks or longer and were exposed to 500 mg of ethylene oxide per liter at 54.4 ± 3 C and 10, 50, and 95% relative humidity in a specially designed thermochemical death rate apparatus. A fifth group did not receive any preconditioning treatment and was exposed immediately after preparation, in the same apparatus at the same temperature, to ethylene oxide concentrations of 200, 400, 600, 800, and 1,200 mg/liter and relative humidities of 15, 30, 50, 60, and 90%. The resistance of the spores on both types of surfaces to ethylene oxide increased proportionately with the Aw of the conditioning environment. The study also showed that moisture in the exposure system was not as critical a variable as the ethylene oxide concentration. The spore destruction rates, irrespective of the carrier types at all concentrations and at different humidities, varied little from one another. The decimal reduction values were reduced as the ethylene oxide concentration increased, and no optimal exposure humidity concentration was observed.
PMCID: PMC376629  PMID: 4984365
17.  Evaluation of Moisture-Related Attenuation Coefficient and Water Diffusion Velocity in Human Skin Using Optical Coherence Tomography 
Sensors (Basel, Switzerland)  2013;13(4):4041-4050.
In this study, time-resolved optical coherence tomography (OCT) scanning images of the process of water diffusion in the skin that illustrate the enhancement in the backscattered intensities due to the increased water concentration are presented. In our experiments, the water concentration in the skin was increased by soaking the hand in water, and the same region of the skin was scanned and measured with the OCT system and a commercial moisture monitor every three minutes. To quantitatively analyze the moisture-related optical properties and the velocity of water diffusion in human skin, the attenuation coefficients of the skin, including the epidermis and dermis layers, were evaluated. Furthermore, the evaluated attenuation coefficients were compared with the measurements made using the commercial moisture monitor. The results demonstrate that the attenuation coefficient increases as the water concentration increases. Furthermore, by evaluating the positions of center-of mass of the backscattered intensities from OCT images, the diffusion velocity can be estimated. In contrast to the commercial moisture monitor, OCT can provide three-dimensional structural images of the skin and characterize its optical property, which together can be used to observe morphological changes and quantitatively evaluate the moisture-related attenuation coefficients in different skin layers.
PMCID: PMC3673069  PMID: 23529149
optical coherence tomography; moisture; attenuation coefficient; water diffusion
18.  Cadmium induces changes in corticotropic and prolactin cells in the Podarcis sicula lizard pituitary gland 
We analyzed the effect of cadmium on corticotropic (ACTH) and prolactin (PRL) cells in the pituitary gland of the Podarcis sicula (P. sicula) lizard under chronic exposure to this metal. Adult lizards were given CdCl2 in drinking water at the dose of 10 µg/10 g body mass for 120 days. Light microscopy was performed after histological and immunohistochemical staining, and the effects were followed at regular time intervals up to 120 days post-treatment. We detected substantial variations in the general morphology of the pituitary: unlike the control lizards in which the gland appeared compact, the treated lizards showed a glandular tissue with dilated spaces that were more extensive at 90 and 120 days. PRL and ACTH cells showed an increase in occurrence and immunostaining intensity in treated lizards in comparison with the same cells of control animals. This cellular increase peaked for PRL at 30 days in the rostral, medial and also caudal pars distalis of the gland. ACTH cells appeared to increase markedly after 60 days of treatment in both the pars distalis and the pars intermedia. Again, at 60 days small, isolated ACTH cells were also found in the caudal pars distalis in which these cells were generally absent. However, at 120 days both these cellular types showed an occurrence, distribution and morphology similar to those observed in the control lizards. In lizards, protracted oral exposure to cadmium evidently involves an alteration of the normal morphology of the gland and an inhibitory effect of ACTH and PRL cells, since they increase in occurrence and immunostaining. Yet in time the inhibitory effect of cadmium on ACTH and PRL cells falls back and their occurrence appears similar to that of the control lizard.
PMCID: PMC3167330  PMID: 21263744
cadmium; corticotropic and prolactin cells; lizard.
19.  Brochosomal coats turn leafhopper (Insecta, Hemiptera, Cicadellidae) integument to superhydrophobic state 
Leafhoppers (Insecta, Hemiptera, Cicadellidae) actively coat their integuments with brochosomes, hollow proteinaceous spheres of usually 200–700 nm in diameter, with honeycombed walls. The coats have been previously suggested to act as a water-repellent and anti-adhesive protective barrier against the insect's own exudates. We estimated their wettability through contact angle (CA) measurements of water, diiodomethane, ethylene glycol and ethanol on detached wings of the leafhoppers Alnetoidia alneti, Athysanus argentarius and Cicadella viridis. Intact brochosome-coated integuments were repellent to all test liquids, except ethanol, and exhibited superhydrophobicity, with the average water CAs of 165–172°, and the apparent surface free energy (SFE) estimates not exceeding 0.74 mN m−1. By contrast, the integuments from which brochosomes were removed with a peeling technique using fluid polyvinylsiloxane displayed water CAs of only 103–129° and SFEs above 20 mN m−1. Observations of water-sprayed wings in a cryo-scanning electron microscope confirmed that brochosomal coats prevented water from contacting the integument. Their superhydrophobic properties appear to result from fractal roughness, which dramatically reduces the area of contact with high-surface-tension liquids, including, presumably, leafhopper exudates.
PMCID: PMC3574307  PMID: 23235705
brochosome; surface; insect; superhydrophobicity; wettability; contact mechanics
20.  Physical chemical stability of warfarin sodium 
AAPS PharmSci  2001;3(1):18-25.
Crystalline warfarin sodium is an isopropanol clathrate containing 8.3% isopropyl alcohol (IPA) and 0.57% water upon receipt. The hygroscopicity and impact of moisture on IPA status as well as on the stability of the clathrate was studied at different relative humidities. The IPA loss and water uptake were simultaneous but they did not exchange at 1:1 molar ratio. At 58% relative humidity (RH) or below, the exchange process was insignificant. At 68% RH or above, the clathrate tended to lose IPA while absorbing water and reverting to the amorphous state. The rate of IPA loss and moisture uptake was a function of RH. The thermal stability of the crystalline warfarin sodium was also examined. Physical change occurred after isothermal storage for 24 hours at 80°C and 11 hours at 120°C. The rate of IPA loss was temperature dependent.
PMCID: PMC2751235  PMID: 11741254
warfarin sodium; isopropyl alcohol; clathrate; amorphous; crystallinity; physical stability; thermal stability
21.  Effect of humidity on the disintegrant property of α-cellulose, Part II: A technical note 
AAPS PharmSciTech  2005;6(1):E31-E34.
The summary is that the high humidity impaired the disintegrant property of α-cellulose in all 3 tablets tested. Tablets of aspirin, which is the more hygroscopic drug, were also more sensitive to the humidity effect, while tablets of chloroquine phosphate, which is a water-soluble drug, were the least sensitive to the humidity effect. The results permit the conclusion that moisture uptake with subsequent gelling of the α-cellulose is the mechanism of impairment of its disintegrant property. The tablets would not normally be stored under an RH as high as 100%, nevertheless, the results of the accelerated stability study have underscored the need to protect tablets containing α-cellulose as disintegrant from moisture.
PMCID: PMC2750408  PMID: 16353960
disintegrant property of α-cellulose; humidity effect; tablet hydration
22.  Root dentin body moisture changes caused by ascorbic acid 
Journal of dentistry  2009;37(6):475-479.
To quantify in vitro the root dentin moisture (DM) when soaked in 10% ascorbic acid solution (Group A) and distilled water (Group B) for up to 14 days.
Forty-four extracted human mandibular single-rooted teeth were sectioned perpendicular to the long axis at the CEJ to access the root dentin. The samples were divided into groups A and B. Baseline (day 0) DM was measured using a digital grain moisture meter. One sample was placed in each tube, which was then filled with solution. All tubes were kept at 37°C and 100% humidity. DM was measured after 1, 3, 7, and 14 days. The baseline DM value was used as a covariate in the generalized estimating equation (GEE) analysis to account for the difference in the baseline DM between the two groups.
The mean DM(%)values±standard deviation on days 0, 1, 3, 7, and 14 were 11.4±1.08, 17.1±0.87, 18.2±0.76, 18.4±0.77, and 17.9±0.90 in Group A, and 10.2±0.95, 12.8±0.90, 13.3±0.95, 13.0±0.91, and 13.2±0.89 in Group B, respectively. Group A had significantly higher baseline DM than Group B (p=0.006). After adjusting for differences in the baseline, the GEE analysis indicated that, on average, Group A had a significantly higher increase in DM than Group B, with means±standard deviation of 4.35±0.26.
The moisture increase in the ascorbic acid group was greater than that in the distilled water group. Soaking root dentin in the unreplenished ascorbic acid solution or distilled water beyond 3 days did not further increase DM.
PMCID: PMC2684822  PMID: 19346052
Ascorbic acid; Bonding; Dentin moisture; Generalized estimating equation analysis; Rapid non-destructive method
23.  Moisture-induced solid state instabilities in α-chymotrypsin and their reduction through chemical glycosylation 
BMC Biotechnology  2010;10:57.
Protein instability remains the main factor limiting the development of protein therapeutics. The fragile nature (structurally and chemically) of proteins makes them susceptible to detrimental events during processing, storage, and delivery. To overcome this, proteins are often formulated in the solid-state which combines superior stability properties with reduced operational costs. Nevertheless, solid protein pharmaceuticals can also suffer from instability problems due to moisture sorption. Chemical protein glycosylation has evolved into an important tool to overcome several instability issues associated with proteins. Herein, we employed chemical glycosylation to stabilize a solid-state protein formulation against moisture-induced deterioration in the lyophilized state.
First, we investigated the consequences of moisture sorption on the stability and structural conformation of the model enzyme α-chymotrypsin (α-CT) under controlled humidity conditions. Results showed that α-CT aggregates and inactivates as a function of increased relative humidity (RH). Furthermore, α-CT loses its native secondary and tertiary structure rapidly at increasing RH. In addition, H/D exchange studies revealed that α-CT structural dynamics increased at increasing RH. The magnitude of the structural changes in tendency parallels the solid-state instability data (i.e., formation of buffer-insoluble aggregates, inactivation, and loss of native conformation upon reconstitution). To determine if these moisture-induced instability issues could be ameliorated by chemical glycosylation we proceeded to modify our model protein with chemically activated glycans of differing lengths (lactose and dextran (10 kDa)). The various glycoconjugates showed a marked decrease in aggregation and an increase in residual activity after incubation. These stabilization effects were found to be independent of the glycan size.
Water sorption leads to aggregation, inactivation, and structural changes of α-CT as has been similarly shown to occur for many other proteins. These instabilities correlate with an increase in protein structural dynamics as a result of moisture exposure. In this work, we present a novel methodology to stabilize proteins against structural perturbations in the solid-state since chemical glycosylation was effective in decreasing and/or preventing the traditionally observed moisture-induced aggregation and inactivation. It is suggested that the stabilization provided by these chemically attached glycans comes from the steric hindrance that the sugars conveys on the protein surface therefore preventing the interaction of the protein internal electrostatics with that of the water molecules and thus reducing the protein structural dynamics upon moisture exposure.
PMCID: PMC2924255  PMID: 20696067
24.  Analysis of electrical property changes of skin by oil-in-water emulsion components 
ObjectivesAs the ‘Dry Skin Cycle’ produces continuous deterioration, cosmetic xerosis (flaky, dry skin) is one of the major concerns to most consumers. The purpose of this study was to investigate the moisturizing effect of oil-in-water (O/W) emulsion components. There are numerous types of oils, waxes, polyols and surfactants used as ingredients in skincare products. However, the moisturizing effect of each ingredient and understanding each use to make an effective moisturizing products are still not well understood.
Methods To provide answers to these questions, we investigated the moisturizing effect of widely used 41 components (four different classes) in a simple O/W emulsion using capacitance methods. 106 different single oils, and combinations of oil with oil, wax, humectants, and surfactant were formulated and tested.
Results In this study, we found that most of the O/W emulsion components had hydration effects on the skin. (i) The average relative water content increase (RWCI) rate of a single oil-based emulsion was 11.8 ± 5.2% (SE) and 7.9 ± 6.0% (SE) at 3 and 6 h, respectively. (ii) An oil combination emulsion showed an average RWCI rate similar to that of a single oil-based emulsion, 12.6 ± 6.0% (SE) and 12.1 ± 6.4% (SE) at 3 and 6 h, respectively (iii) A combination of waxes with oil showed an average RWCI rate of 16 ± 5.6% (SE) and 12.4 ± 4.5% (SE) at 3 and 6 h, respectively. (iv) Humectant combinations showed the highest average RWCI rate 28 ± 7.3% (SE) and 22.2 ± 7.5% (SE) at 3 and 6 h, respectively (v) Surfactant combinations had an average RWCI of 10.8 ± 4.5% (SE) and 6.0 ± 4.0% (SE) at 3 and 6 h, respectively.
Conclusion Interestingly, it was difficult to find moisturizing power differences among samples in the same group. Only the humectants group showed significant differences among samples. Glycerine and urea showed significant skin hydration effects compared with other humectants. We also found a significant moisturizing effect by analysing the chemical functional groups; amide class had a higher hydration effect than betaines and disaccharides in humectants combination.
Objectif Puisque le «cycle de la peau sèche” produit une détérioration continue, la xérose cosmétique (squameuse, peau sèche) est l’une des préoccupations majeures pour la plupart des consommateurs. Le but de cette étude était d’étudier l’effet hydratant des composants d’émulsions H / E. Il existe de nombreux types d’huiles, des cires, de polyols, et des tensioactifs utilisés comme ingrédients dans les produits de soins de la peau. Cependant, l’effet hydratant de chaque ingrédient et de leur utilisation dans des produits hydratants efficaces ne sont pas encore bien compris.
MethodesPour apporter des réponses à ces questions, nous avons étudié l’effet hydratant des 41 éléments (4 classes différentes) largement utilisés dans une émulsion simple O/W en utilisant des méthodes de capacitance. 106 huiles individuelles différentes et des combinaisons d’huile avec de l’huile, de la cire, des humectants, et de tensioactifs ont été formulées et testées.
ResultatsDans cette étude, nous avons constaté que la plupart des composants des émulsions huile-dans-eau (H/E) possédaient des effets d’hydratation de la peau. (i) Le taux moyen d’augmentation d’eau (RWCI = relative water content increase) d’une émulsion à base d’une seule huile était de 11,8 ± 5,2% (SE) et de 7,9 ± 6,0% (SE) à 3 et 6 h, respectivement. (ii) Une émulsion de combinaison d’huile montrait une RWCI similaire à celle d’une émulsion à base d’huile unique, 12,6 ± 6,0% (SE) et 12,1 ± 6,4% (SE) à 3 et 6 h, respectivement. (iii) Une combinaison des cires avec de l’huile présentait une RWCI de 16 ± 5,6% (SE) et 12,4 ± 4,5% (SE) à 3 et 6 h, respectivement. (iv) Les combinaisons d’humectant ont montré la plus forte augmentation avec +28 ± 7,3% (SE) et 22,2 ± 7,5% (SE) à 3 et 6 h, respectivement. (v) Les combinaisons de tensioactifs ont une RWCI moyenne de 10,8 ± 4,5% (SE) et de 6,0 ± 4,0% (SE) à 3 et 6 h, respectivement.
ConclusionFait intéressant, il était difficile de trouver des différences de pouvoir d’hydratation entre les échantillons dans le même groupe. Seul le groupe des humectants a montré des différences significatives entre les échantillons. La glycérine et l’urée ont montré des effets significatifs sur l’hydratation de la peau par rapport aux autres humectants. Nous avons également constaté un effet hydratant important en analysant les groupes fonctionnels chimiques; la classe “amide” a eu un effet d’hydratation plus élevé que les bétaînes et disaccharides dans les combinaisons des humectants.
PMCID: PMC3807609  PMID: 23621673
corneometer; oil-in-water emulsion; poliol; relative water content increase rate; relative water contents
25.  Hyaluronic acid: A key molecule in skin aging 
Dermato-endocrinology  2012;4(3):253-258.
Skin aging is a multifactorial process consisting of two distinct and independent mechanisms: intrinsic and extrinsic aging. Youthful skin retains its turgor, resilience and pliability, among others, due to its high content of water. Daily external injury, in addition to the normal process of aging, causes loss of moisture. The key molecule involved in skin moisture is hyaluronic acid (HA) that has unique capacity in retaining water. There are multiple sites for the control of HA synthesis, deposition, cell and protein association and degradation, reflecting the complexity of HA metabolism. The enzymes that synthesize or catabolize HA and HA receptors responsible for many of the functions of HA are all multigene families with distinct patterns of tissue expression. Understanding the metabolism of HA in the different layers of the skin and the interactions of HA with other skin components will facilitate the ability to modulate skin moisture in a rational manner.
PMCID: PMC3583886  PMID: 23467280
hyaluronic acid; hyaluronic acid synthases; hyaluronidases; CD44; RHAMM; skin aging

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