Morphological characterization of in-vitro human hair keratinolysis,produced by identified wild strains of Chrysosporium species

Chrysosporium species were isolated from soil and keratinized material. Primary isolation was performed following the general method of hair baiting on modified Czapek-agar media with washed, defated and sterilized human hair fragments added. Strains were maintained in test tubes of potato dextrose agar at 29 °C and cultivated on phytone yeast extract agar at 28 °C for 14 days for identification. Isolates were characterized using Van Oorschot's key. Keratinolytic activity was expressed following a subjective scale representing degree/severity of attack upon hair surface and presence of fungal structures observed in substrate. Culture results and characterization methods were effective for soil Chrysosporium strain isolation. A new hair attack mode is described. Of 71 keratinolytic fungal isolates, eight (12%) Chrysosporium species were identified. One keratinolytic Chrysosporium sp. isolate is yet to be identified.This revised version was published online in October 2005 with corrections to the Cover Date.     

Vancomycin Tolerant,Methicillin-Resistant Staphylococcus aureus Reveals the Effects of Vancomycin on Cell Wall Thickening

Methicillin-resistant Staphylococcus aureus (MRSA) is an important opportunistic pathogen that causes both healthcare- and community-acquired infections. An increase in the incidence of these infections may lead to a substantial change in the rate of vancomycin usage. Incidence of reduced susceptibility to vancomycin has been increasing worldwide for the last few years, conferring different levels of resistance to vancomycin as well as producing changes in the cell wall structure. The aim of the present study was to determine the effect of vancomycin on cell wall thickening in clinical isolates of vancomycin-tolerant (VT) MRSA obtained from pediatric patients. From a collection of 100 MRSA clinical isolates from pediatric patients, 12% (12/100) were characterized as VT-MRSA, and from them, 41.66% (5/12) exhibited the heterogeneous vancomycin-intermediate S. aureus (hVISA) phenotype. Multiplex-PCR assays revealed 66.66% (8/12), 25% (3/12), and 8.33% (1/12) of the VT-MRSA isolates were associated with agr group II, I, and III polymorphisms, respectively; the II-mec gene was amplified from 83.3% (10/12) of the isolates, and the mecIVa gene was amplified from 16.66% (2/12) of the isolates. Pulsed field electrophoresis (PFGE) fingerprint analysis showed 62% similarity among the VT-MRSA isolates. Thin transverse sections analyzed by transmission electron microscopy (TEM) revealed an average increase of 24 nm (105.55%) in the cell wall thickness of VT-MRSA compared with untreated VT-MRSA isolates. In summary, these data revealed that the thickened cell walls of VT-MRSA clinical isolates with agr type II and SCCmec group II polymorphisms are associated with an adaptive resistance to vancomycin.     

Size–weight relationships of batoids captured by artisanal fishery in the southern Gulf of California,Mexico

This study reports the size–weight relationships (SWR) for nine batoid species that are frequently fished by the artisanal fisheries in the southern Gulf of California. Analysis included a total of 2,012 specimens, caught from October 2013 to July 2016. The slope values (b) oscillated from 2.80 to 3.56. Growth was isometric for five species and positively allometric for four. There were differences in SWR between sexes for three species being in all cases the female greater and heavier than males. This is the first analysis of SWR for the batoid species studied in the Gulf of California.     

Temporary immersion bioreactors (TIB) provide a versatile,cost-effective and reproducible in vitro analysis of the response of pineapple shoots to salinity and drought

Effects of salinity (NaCl) and the carbon source mannitol (0–200 mM) on micropropagation of pineapple cv. MD2 were analyzed in temporary immersion bioreactors (TIBs). Shoot multiplication rate, shoot cluster fresh weight and levels of aldehydes, chlorophylls, carotenoids and phenolics were determined in the plant material. The content of soluble phenolics in the culture medium was also evaluated. NaCl or mannitol above concentrations of 50 mM decreased pineapple shoot multiplication and fresh weight significantly. Two hundred mM NaCl decreased multiplication rate by 71.5% and cluster fresh weight by 40.0%. NaCl increased 2.4 times the levels of other aldehydes; 1.4 times the soluble phenolics in shoots; and 1.4 times the phenolics excreted to the culture medium. On the other hand, mannitol decreased the multiplication rate and cluster fresh weight by about 60%. Mannitol increased the contents of chlorophyll b 1.4 times and soluble phenolics 2.1 times. Results indicated that pineapple cv. MD2 is more sensitive to NaCl than to mannitol. Multiplication rates indicate that a 50% reduction was obtained with 37.4 mM NaCl and 66.5 mM mannitol. These concentrations can be used to stress shoots during micropropagation in TIBs and screen for/detect somaclonal variants with an increased salinity or drought tolerance.     

Carbon metabolism in leaves of micropropagated sugarcane during acclimatization phase

The activity of the main enzymes related to the sucrose metabolism, photosynthesis, and sucrose concentration were studied in sugarcane (Saccharum spp hybrid) plantlets. Acclimatization was developed in two steps. (1) Light intensity of 1,000 μmol m⁻² s⁻¹ and 90% relative humidity during the first 21 d; followed by 2,000 μmol m⁻² s⁻¹ and approximately 80% of relative humidity. All measurements were carried out at the end of rooting phase concomitant with day 0 of acclimatization and at 7-d intervals thereafter (0, 7, 14, 21, 28, 35, 42 d). As the in vitro plantlets were transferred to the acclimatization phase, photosynthesis increased significantly during the first 7 d. After this period, the increase was constant with only a small but nonsignificant decline after being transferred to the uncontrolled external conditions. The activity of the sucrose synthase began to show a decrease, starting from day 7, and was related to the changes that began to happen in these plants from its adaptation to new ex vitro conditions. Due to the increase of fresh weight favored by the high light intensity and lower relative humidity, an increase of the sucrose phosphate synthase activity was observed. The maximum activity of the acid and neutral invertases was reached at 14 and 21 d, respectively, after 21 d of acclimatization period. There was a marked tendency for the activity of both enzymes to decrease. The sucrose content was decreased only in the first 7 d. The metabolism of sugarcane plantlets seemed to be susceptible to the environmental changes during the acclimatization phase but did not contribute to inhibitory factors for normal development.     

Observations of killer whales (Orcinus orca) in the fjords of Chilean Patagonia

Killer whales occur in Chilean waters, but their seasonality, diets, and overall distribution are poorly known. Here, we present data on group composition, site fidelity, and prey species of individual killer whales recorded in 63 sightings between 2004 and 2012 in the Chilean Patagonian fjords. Group sizes were small (mean = 5, SD = 2.5 for calf groups; mean = 3, SD = 1.5 for non-calf groups), and occurrence was significantly lower in summer months. Photographs enabled identification of 55 individuals from natural markings, and all resembled Southern Ocean type A killer whales. The species was transient in the area; the average presence was 1.7 days with 60 % of individuals seen only once. Occupancy was 3–44 days, and low levels of site fidelity were recorded (64 % of individuals were seen in only 1 year). Group composition at short time scales (3 months) remained stable, but we detected changes at longer time scales. Prey included fish, otariids, and seabirds. Twelve individual killer whales showed a broad dietary spectrum: 3 ate otariids and fish, 2 ate birds and otariids, and 7 ate otariids, birds, and possibly fish. Further research is needed to increase basic biological knowledge of these killer whales and to determine the relationship with type A killer whales from the Southern Ocean.     

Prevalence of and risk factors for colic in horses that display crib-biting behaviour

Background

Crib-biting and windsucking (CBWS) behaviour in horses has been associated with increased risk of colic in general, recurrence of colic and specific forms of colic. The aims of the present study were to determine the prevalence of colic within a population of horses that display CBWS behaviour and to identify risk factors for colic.

Methods

Owners/carers of horses in the general UK equine population that display CBWS behaviour were invited to participate in a questionnaire-based survey about the management and health of these horses. Data were obtained for a number of variables considered to be possible risk factors for colic. The prevalence of colic was calculated and multivariable logistic regression was used to identify associations between horse- and management-level variables for two outcomes of interest: a history of colic ever and a history of colic in the previous 12 months.

Results

Data were obtained for 367 horses. One or more episodes of colic had been observed in 130 horses (35.4%). A total of 672 colic episodes were reported and 13 colic episodes required surgical intervention in 12 horses. Where the horse/pony had been in that persons care over the previous 12 months (n=331), colic had been observed in 67 horses (20.2%) during that time. A total of 126 colic episodes were reported in the preceding 12 months of which veterinary attendance was required in 69 (54.8%) episodes. Increased duration of ownership, increased duration of stabling in the Autumn months (September-November), crib-biting/windsucking behaviour associated with eating forage and horses that were fed haylage were associated with increased risk of colic (ever). Increasing severity (frequency) of CBWS behaviour and increased duration of stabling in the Autumn were associated with increased risk of colic in the previous 12 months.

Conclusions

The prevalence of colic in a population of horses that display CBWS appeared to be relatively high. The results of this study can be used to identify horses that display CBWS who are at increased risk of colic and identifies areas for further research to determine if there are ways in which this risk might be reduced.

     

Proteomic identification of activin receptor-like kinase-1 as a differentially expressed protein during hyaloid vascular system regression

The hyaloid vascular system (HVS) is a transient network of capillaries that nourishes the embryonic lens and the primary vitreous of the developing eye. We used proteomic analysis and immunohistochemical staining to identify activin receptor-like kinase-1 (ALK1), a type I receptor for transforming growth factor-beta1, during the HVS regression phase. In addition, we overexpressed ALK1 in corneas implanted with bFGF (basic fibroblast growth factor) pellets and observed that ALK1 overexpression resulted in inhibition of bFGF-induced corneal neovascularization in vivo. Our data suggest that ALK1 may play a role in HVS regression during ocular development.