Test method development to evaluate hot,humid air decontamination of materials contaminated with Bacillus anthracis ∆Sterne and B. thuringiensis Al Hakam spores

Aims

To develop test methods and evaluate the survival of Bacillus anthracis ?Sterne and Bacillus thuringiensis Al Hakam spores after exposure to hot, humid air.

Methods and Results

Spores (>7 logs) of both strains were dried on six different test materials. Response surface methodology was employed to identify the limits of spore survival at optimal test combinations of temperature (60, 68, 77°C), relative humidity (60, 75, 90%) and time (1, 4, 7 days). No spores survived the harshest test run (77°C, 90% r.h., 7 days), while > 6·5 logs of spores survived the mildest test run (60°C, 60% r.h., 1 day). Spores of both strains inoculated on nylon webbing and polypropylene had greater survival rates at 68°C, 75% r.h., 4 days than spores on other materials. Electron microscopy showed no obvious physical damage to spores using hot, humid air, which contrasted with pH‐adjusted bleach decontamination.

Conclusions

Test methods were developed to show that hot, humid air effectively inactivates B. anthracis ?Sterne and B. thuringiensis Al Hakam spores with similar kinetics.

Significance and Impact of the Study

Hot, humid air is a potential alternative to conventional chemical decontamination.     

The association between leukocytes and sperm quality is concentration dependent

Background  

To evaluate the association between leukocytes (polymorphonuclear granulocytes -PMNL) and semen parameters at different leukocyte concentrations.     

Telomere length determined by the fluorescence in situ hybridisation distinguishes malignant and benign cells in cytological specimens

Background

Telomeres are tandem repeats of TTAGGG at the end of eukaryotic chromosomes that play a key role in preventing chromosomal instability. The aim of the present study is to determine telomere length using fluorescence in situ hybridisation (FISH) on cytological specimens.

Methods

Aspiration samples (n = 41) were smeared on glass slides and used for FISH.

Results

Telomere signal intensity was significantly lower in positive cases (cases with malignancy, n = 25) as compared to negative cases (cases without malignancy, n = 16), and the same was observed for centromere intensity. The difference in DAPI intensity was not statistically significant. The ratio of telomere to centromere intensity did not show a significant difference between positive and negative cases. There was no statistical difference in the signal intensities of aspiration samples from ascites or pleural effusion (n = 23) and endoscopic ultrasound‐guided FNA samples from the pancreas (n = 18).

Conclusions

The present study revealed that telomere length can be used as an indicator to distinguish malignant and benign cells in cytological specimens. This novel approach may help improve diagnosis for cancer patients.     

Enhanced inhibition of Aspergillus niger on sedge (Lepironia articulata) treated with heat‐cured lime oil

Aims

This study aimed to examine heat curing effect (30–100°C) on antifungal activities of lime oil and its components (limonene, p‐cymene, β‐pinene and α‐pinene) at concentrations ranging from 100 to 300 μl ml^?1 against Aspergillus niger in microbiological medium and to optimize heat curing of lime oil for efficient mould control on sedge (Lepironia articulata).

Methods and Results

Broth dilution method was employed to determine lime oil minimum inhibitory concentration, which was at 90 μl ml^?1 with heat curing at 70°C. Limonene, a main component of lime oil, was an agent responsible for temperature dependencies of lime oil activities observed. Response surface methodology was used to construct the mathematical model describing a time period of zero mould growth on sedge as functions of heat curing temperature and lime oil concentration. Heat curing of 90 μl ml^?1 lime oil at 70°C extended a period of zero mould growth on sedge to 18 weeks under moist conditions.

Conclusions

Heat curing at 70°C best enhanced antifungal activity of lime oil against A. niger both in medium and on sedge.

Significance and Impact of the Study

Heat curing of lime oil has potential to be used to enhance the antifungal safety of sedge products.     

Past vegetation dynamics in the Yellowstone region highlight the vulnerability of mountain systems to climate change

Aim

Reconstruct the long‐term ecosystem dynamics of the region across an elevational gradient as they relate to climate and local controls. In particular, we (1) describe the dominant conifers' history; (2) assess changes in vegetation composition and distribution; and (3) note periods of abrupt change versus stability as means of better understanding vegetation responses to environmental variability.

Location

Greater Yellowstone Ecosystem (GYE; USA).

Time period

16.5 ka bp ‐present.

Major taxa studied

Juniperus, Picea, Abies, Pinus, Pseudotsuga.

Methods

The vegetation reconstruction was developed from 15 pollen records. Results were interpreted based on modern pollen–vegetation relationships estimated from a suite of regression‐based approaches.

Results

Calibrated pollen data suggest that late‐glacial vegetation, dominated by shrubs and Juniperus, lacks a modern counterpart in the area. Picea, Abies and Pinus expanded at 16 ka bp in association with postglacial warming and co‐occurred in mixed‐conifer parkland/forest after 12 ka bp . This association along with Pinus contorta forest, which was present after 9 ka bp , has persisted with little change at middle and high elevations to the present day. This stability contrasts with the dynamic history of plant communities at low elevations, where shifts between parkland, steppe and forest over the last 8,000 years were likely driven by variations in effective moisture and fire.

Main conclusions

The postglacial vegetation history of the GYE highlights the dynamic nature of mountain ecosystems and informs on their vulnerability to future climate change: (1) most of the conifers have been present in the area for >12,000 years and survived climate change by adjusting their elevational ranges; (2) some plant associations have exhibited stability over millennia as a result of nonclimatic controls; and (3) present‐day forest cover is elevationally more compressed than at any time in history, probably due to the legacy of the Medieval Climate Anomaly and the Little Ice Age.     

Computational genes: a tool for molecular diagnosis and therapy of aberrant mutational phenotype

Background  

A finite state machine manipulating information-carrying DNA strands can be used to perform autonomous molecular-scale computations at the cellular level.     

Applying the polio model to New Zealand: The contingent role of socioeconomic status in infectious disease mortality

Objectives

The traditional polio model depicts a positive relationship between the disease and socioeconomic status (SES), with higher SES associated with exposure to the poliovirus beyond infancy/early childhood and a higher mortality rate. This study uses occupation data from non-Māori New Zealand death registrations and the Census to assess evidence for differential mortality by SES during the polio epidemics of 1916, 1924–25, and 1936–37.

Materials and Methods

Polio deaths were classified by father's occupation using the Caversham Project scheme, which includes nine collapsible urban occupational strata and codes rural occupations separately. Evidence for differential mortality and differences in age at death between rural and urban areas and among urban occupational strata was assessed using nonparametric Mann–Whitney U, Kruskal–Wallis, Jonckheere-Terpstra, and chi-square tests.

Results

There was limited evidence of either differential mortality or differences in age at death among collapsed urban strata, mainly in 1924/25, only partially meeting the expectations of the traditional polio model. For 1916 only, the rural group had a higher proportion of deaths (χ² (1, n = 95) = 8.341, p = 0.0039, φ = 0.30)) and higher age at death (U = 828.00, p = 0.026, r = −0.23).

Discussion

These results suggest that rural New Zealand was more isolated from poliovirus infection prior to 1916, but thereafter rural and urban groups faced more similar exposure patterns and mortality—at least among non-Māori. The degree to which occupational categories reflect conditions of exposure requires further research.

     

Comparative Study of 250 mg/day Terbinafine and 100 mg/day Itraconazole for the Treatment of Cutaneous Sporotrichosis

Abstract  

Itraconazole is currently used for the treatment of cutaneous sporotrichosis. Terbinafine at a daily dose of 250 mg has been successfully applied to the treatment of cutaneous sporotrichosis.     

Fate of Escherichia coli O145 present naturally in bovine slurry applied to vegetables before harvest,after washing and simulated wholesale and retail distribution

Aims

To determine the fate of Escherichia coli on vegetables that were processed through commercial wash treatments and stored under simulated retail conditions at 4°C or wholesale at fluctuating ambient temperatures (0–25°C, dependent on season).

Methods and Results

Bovine slurry that was naturally contaminated with E. coli O145 was applied without dilution or diluted 1:10 using borehole water to growing potatoes, leeks or carrots. Manure was applied 1 week prior to harvest to simulate a near‐harvest contamination event by manure deposition or an application of contaminated water to simulate a flooding event or irrigation from a contaminated water source. At harvest, crops were contaminated at up to 2 log cfu g^?1. Washing transferred E. coli into the water of a flotation tank used for potato washing and did not completely remove all traces of contamination from the crop. Manure‐contaminated potatoes were observed to contain 0·72 cfu E. coli O145 g^?1 after processing and retail storage. Manure‐contaminated leeks harboured 0·73–1·55 cfu E. coli O145 g^?1 after washing and storage. There was no cross‐contamination when leeks were spray washed. Washing in an abrasive drum resulted in less than perfect decontamination for manure‐contaminated carrots. There were five post‐distribution isolations from carrots irrigated with contaminated water 24 h prior to harvest.

Conclusions

Standard commercial washing and distribution conditions may be insufficient to reliably control human pathogenic E. coli on fresh produce.

Significance and Impact

Previous speculation that the cause of a UK foodborne disease outbreak was soil from imperfectly cleaned vegetables is plausible.     

Continental estimates of forest cover and forest cover changes in the dry ecosystems of Africa between 1990 and 2000

Aim

This study provides regional estimates of forest cover in dry African ecoregions and the changes in forest cover that occurred there between 1990 and 2000, using a systematic sample of medium‐resolution satellite imagery which was processed consistently across the continent.

Location

The study area corresponds to the dry forests and woodlands of Africa between the humid forests and the semi‐arid regions. This area covers the Sudanian and Zambezian ecoregions.

Methods

A systematic sample of 1600 Landsat satellite imagery subsets, each 20 km × 20 km in size, were analysed for two reference years: 1990 and 2000. At each sample site and for both years, dense tree cover, open tree cover, other wooded land and other vegetation cover were identified from the analysis of satellite imagery, which comprised multidate segmentation and automatic classification steps followed by visual control by national forestry experts.

Results

Land cover and land‐cover changes were estimated at continental and ecoregion scales and compared with existing pan‐continental, regional and local studies. The overall accuracy of our land‐cover maps was estimated at 87%. Between 1990 and 2000, 3.3 million hectares (Mha) of dense tree cover, 5.8 Mha of open tree cover and 8.9 Mha of other wooded land were lost, with a further 3.9 Mha degraded from dense to open tree cover. These results are substantially lower than the 34 Mha of forest loss reported in the FAO's 2010 Global Forest Resources Assessment for the same period and area.

Main conclusions

Our method generates the first consistent and robust estimates of forest cover and change in dry Africa with known statistical precision at continental and ecoregion scales. These results reduce the uncertainty regarding vegetation cover and its dynamics in these previously poorly studied ecosystems and provide crucial information for both science and environmental policies.     

Polylepis woodland dynamics during the last 20,000 years

Aim

To determine the palaeoecological influences of climate change and human land use on the spatial distribution patterns of Polylepis woodlands in the Andes.

Location

Tropical Andes above 2,900 m between 2°S and 18°S of latitude.

Methods

Pollen and charcoal data were gathered from 13 Andean lake sediment records and were rescaled by the maximum value in each site. The rescaled pollen data were used to estimate a mean abundance and coefficient of variation to show woodland expansions/contractions and woodland fragmentation over the last 20,000 years. The rescaled charcoal was displayed as a 200‐year moving median using 500‐year bins to infer the influence of fire on woodland dynamics at landscape scale. Pollen and charcoal were compared with speleothem, clastic flux and archaeological data to assess the influence of moisture balance, glacial activity and human impact on the spatial distribution of Polylepis woodlands.

Results

Woodland expansion and fire were correlated with precipitation changes and glacier dynamics from c. 20 to 6 kcal bp (thousands of calibrated years before present). Charcoal abundances between 20 and 12 kcal bp were less common than from 12 kcal bp to modern. However, human‐induced fires were unlikely to be the main cause of a woodland decline centred at 11 kcal bp , as woodlands recovered from 10.5 to 9.5 kcal bp (about twofold increase). Charcoal peaks analogous to those that induced the woodland decline at 11 kcal bp were commonplace post‐9.5 kcal bp but did not trigger an equivalent woodland contraction. An increase in the coefficient of variation after c. 5.5 kcal bp suggests enhanced fragmentation and coincided with the shift from logistic to exponential growth of human populations. Over the last 1,000 years, Polylepis became hyper‐fragmented with over half of sites losing Polylepis from the record and with coefficients of variation paralleling those of glacial times.

Main conclusions

Polylepis woodlands formed naturally patchy woodlands, rather than a continuous vegetation belt, prior to human occupation in the Andes. The main factors controlling pre‐human woodland dynamics were precipitation and landscape heterogeneity. Human activity led to hyper‐fragmentation during the last c. 1,000 years.     

Increased risk of peripheral arterial disease in polymyalgia rheumatica: a population-based cohort study

Introduction  

The present study was conducted to determine whether patients with polymyalgia rheumatica (PMR) are at an increased risk of peripheral arterial disease (PAD).     

The histologic detection of Helicobacter pylori in seropositive subjects is affected by pathology and secretory ability of the stomach

Background

Helicobacter pylori is unevenly distributed in hypochlorhydric environments. The study aim was to elucidate the risk factors for a negative Giemsa staining finding in seropositive subjects by measuring the secretory ability of the stomach.

Methods

Subjects aged over 18 years were included consecutively after endoscopic biopsy at gastric lesions with color or structural changes. Blood was sampled for the serum pepsinogen (PG) assay and H. pylori serology test. After excluding the subjects with past H. pylori eradication, the risk factors for a negative Giemsa staining finding in seropositive subjects were analyzed.

Results

Among 872 included subjects, a discrepancy between the serum anti‐H. pylori IgG and Giemsa staining findings was found in 158 (18.1%) subjects, including 145 Giemsa‐negative, seropositive subjects. Gastric adenocarcinoma/adenoma (OR = 11.090, 95% CI = 3.490‐35.236) and low serum PG II level (OR = 0.931, 95% CI = 0.899‐0.963) were the independent risk factors for a negative Giemsa staining finding in seropositive subjects. The cutoff value of serum PG II level was 7.45 ng/mL (area under curve [AUC] = 0.904, 95% CI = 0.881‐0.927). Follow‐up studies of Giemsa staining at different sites of the stomach revealed that 75% of the Giemsa‐negative seropositive subjects with adenocarcinoma are positive, whereas none of those with low serum PG II level of <7.45 ng/mL revealed positive findings.

Conclusions

The risk of a negative Giemsa staining finding in seropositive subjects is increased in gastric adenocarcinoma/adenoma specimens and in subjects with a diminished gastric secretory ability with low serum PG II level of <7.45 ng/mL. A false‐negative Giemsa staining finding is common in subjects with adenocarcinoma, and therefore, additional biopsies at different sites should be performed in these subjects.     

Non-imprinted allele-specific DNA methylation on human autosomes

Background  

Differential DNA methylation between alleles is well established in imprinted genes and the X chromosomes in females but has rarely been reported at non-imprinted loci on autosomes.     

Selected acute phase CSF factors in ischemic stroke: findings and prognostic value

Background  

Study aimed at investigation of pathogenic role and prognostic value of several selected cerebrospinal fluid acute phase factors that can reflect the severity of ischemic brain damage.     

In situ evaluation of surface roughness and micromorphology of temporary soft denture liner materials at different time intervals

Objective

To perform an in situ evaluation of surface roughness and micromorphology of two soft liner materials for dentures at different time intervals.

Background

The surface roughness of materials may influence the adhesion of micro‐organisms and inflammation of the mucosal tissues. The in situ evaluation of surface roughness and the micromorphology of soft liner materials over the course of time may present results different from those of in vitro studies, considering the constant presence of saliva and food, the changes in temperature and the pH level in the oral cavity.

Materials and methods

Forty‐eight rectangular specimens of each of the two soft liner materials were fabricated: a silicone‐based material (Mucopren Soft) and an acrylic resin‐based material (Trusoft). The specimens were placed in the dentures of 12 participants (n = 12), and the materials were evaluated for surface roughness and micromorphology at different time intervals: 0, 7, 30 and 60 days. Roughness (Ra) was evaluated by means of a roughness tester. Surface micromorphology was evaluated by scanning electron microscopy.

Results

Analysis of variance for randomised block design and Tukey's test showed that surface roughness values were lower in the groups using the silicone‐based material at all the time intervals (P < .0001). The average surface roughness was higher at time interval 0 than at the other intervals, for both materials (P < .0001). The surface micromorphology showed that the silicone material presented a more regular and smoother surface than the acrylic resin‐based material.

Conclusion

The surface roughness of acrylic resin‐based and silicone‐based denture soft liner materials decreased after 7 days of evaluation, leading to a smoother surface over time. The silicone‐based material showed lower roughness values and a smoother surface than the acrylic resin‐based material, thereby making it preferred when selecting more appropriate material, due its tendency to promote less biofilm build‐up.     

Evaluating integrated headache care: a one-year follow-up observational study in patients treated at the Essen headache centre

Background  

Outpatient integrated headache care was established in 2005 at the Essen Headache Centre in Germany. This paper reports outcome data for this approach.     

Handwriting performance in the absence of visual control in writer's cramp patients: Initial observations

Background  

The present study was aimed at investigating the writing parameters of writer's cramp patients and control subjects during handwriting of a test sentence in the absence of visual control.     

Presence of virulence markers in environmental Vibrio vulnificus strains

Aims

This work aims to demonstrate the presence of several genes and factors associated with virulence in strains isolated from the environment at Pueblo Viejo Lagoon, State of Veracruz, Mexico.

Methods and Results

In this study, we investigated the production of V. vulnificus virulence factors, as cytolysin (haemolysin), RTX toxin, metalloprotease, siderophores, capsular polysaccharide, adhesion structures (like type IV pili), and polar and lateral flagella, involved in swimming and swarming (or, at least, the presence of genes encoding some of them) in 40 strains of V. vulnificus isolated from water and food. The results indicate that strains of environmental origin possess potential virulence characteristics.

Conclusions

Caution should be exercised when consuming raw shellfish (especially by those more susceptible risk groups).

Significance and Impact of the Study

This is the first work focused on the evaluation of V. vulnificus virulence factors in Mexico.