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We previously demonstrated that xanthobaccin A from the rhizoplane bacterium Lysobacter sp. strain SB-K88 suppresses damping-off disease caused by Pythium sp. in sugar beet. In this study we focused on modes of Lysobacter sp. strain SB-K88 root colonization and antibiosis of the bacterium against Aphanomyces cochlioides, a pathogen of damping-off disease. Scanning electron microscopic analysis of 2-week-old sugar beet seedlings from seeds previously inoculated with SB-K88 revealed dense colonization on the root surfaces and a characteristic perpendicular pattern of Lysobacter colonization possibly generated via development of polar, brush-like fimbriae. In colonized regions a semitransparent film apparently enveloping the root and micro-colonies were observed on the root surface. This Lysobacter strain also efficiently colonized the roots of several plants, including spinach, tomato, Arabidopsis thaliana, and Amaranthus gangeticus. Plants grown from both sugar beet and spinach seeds that were previously treated with Lysobacter sp. strain SB-K88 displayed significant resistance to the damping-off disease triggered by A. cochlioides. Interestingly, zoospores of A. cochlioides became immotile within 1 min after exposure to a SB-K88 cell suspension, a cell-free supernatant of SB-K88, or pure xanthobaccin A (MIC, 0.01 μg/ml). In all cases, lysis followed within 30 mm in the presence of the inhibiting factor(s). Our data indicate that Lysobacter sp. strain SB-K88 has a direct inhibitory effect on A. cochlioides, suppressing damping-off disease. Furthermore, this inhibitory effect of Lysobacter sp. strain SB-K88 is likely due to a combination of antibiosis and characteristic biofilm formation at the rhizoplane of the host plant. [ABSTRACT FROM AUTHOR]

Southern wilt of geraniums (Pelargonium hortorum), caused by the soilborne bacterium Ralstonia solanacearum race 3 biovar 2 (R3bv2), has inflicted significant economic losses when geranium cuttings latently infected with this quarantine pest were imported into the United States. Little is known about the interaction between R. solanacearum and this ornamental host. Using UW551, a virulent R3bv2 geranium isolate from a Kenyan geranium, we characterized development of Southern wilt disease and R3bv2 latent infection on geranium plants. Following soil inoculation, between 12 and 26% of plants became latently infected, carrying average bacterial populations of 4.8 × 108 CFU/g of crown tissue in the absence of visible symptoms. Such latently infected plants shed an average of 1.3 × 105 CFU/ml in soil run-off water, suggesting a nondestructive means of testing pools of asymptomatic plants. Similarly, symptomatic plants shed 2 × 106 CFU/ml of run off water. A few hundred R. solanacearum cells introduced directly into geranium stems resulted in death of almost all inoculated plants. However, no disease transmission was detected after contact between wounded leaves. Increasing temperatures to 28°C for 2 weeks did not convert all latently infected plants to active disease, although disease development was temperature dependent. Holding plants at 4°C for 48 h, a routine practice during geranium cutting shipment, did not increase frequency of latent infections. R. solanacearum cells were distributed unevenly in the stems and leaves of both symptomatic and latently infected plants, meaning that random leaf sampling is an unreliable testing method. UW551 also caused potato brown rot and bacterial wilt of tomato, surpassing race 1 strain K60 in virulence on tomato at the relatively cool temperature of 24°C. [ABSTRACT FROM AUTHOR]

Amino acid sequence analyses indicate that the Soilborne wheat mosaic virus (SBWMV) 19K protein is a cysteine-rich protein (CRP) and shares sequence homology with CRPs derived from furo-, hordei-, peclu- and tobraviruses. Since the hordei- and pecluvirus CRPs were shown to be pathogenesis factors and/or suppressors of RNA silencing, experiments were conducted to determine if the SBWMV 19K CRP has similar activities. The SBWMV 19K CRP was introduced into the Potato virus X (PVX) viral vector and inoculated to tobacco plants. The SBWMV 19K CRP aggravated PVX-induced symptoms and restored green fluorescent protein (GFP) expression to GFP silenced tissues. These observations indicate that the SBWMV 19K CRP is a pathogenicity determinant and a suppressor of RNA silencing. [ABSTRACT FROM AUTHOR]

Isolates of Tobacco mild green mosaic virus (TMGMV), a member of the genus Tobamovirus, from Nicotiana glauca in southern California fall into two major genotypes, large (TMGMV-L) and small (TMGMV-S), distinguishable by the size of the coat protein (CP) subgenomic RNA. Mixed infections in the field were rare (1.6%), even at sites where both genotypes were common in single infections (62% for TMGMV-S; 37% for TMGMV-L). When plants experimentally protected by TMGMV-L were challenged by TMGMV-S, almost complete cross protection (90% of total plants challenged) was observed regardless of the protective time period (minimum 12 h and maximum 14 days). When plants protected by TMGMV-S were challenged with TMGMV-L, complete cross protection was observed when the protective time was 5 to 14 days. However, when the protective time was 3 days or less, protection by TMGMV-S was greatly reduced (11%), with mixed infections of TMGMV-S and -L predominating (69%), and single infections of the challenge virus TMGMV-L were frequently observed (20%). When TMGMV-S and -L virions were co-inoculated, the virus progeny from individual plants most often contained only the TMGMV-L genome (61%) or, less frequently (39%), both genotypes. Therefore, TMGMV-L was more competitive than TMGMV-S and was able to displace TMGMV-S in experimental situations. The results obtained from cross-protection experiments in the greenhouse would explain the low frequency of natural mixed infections. It is possible that the experimental superior competitiveness of the novel L genotype has already or will play a role in its abundance in southern California. [ABSTRACT FROM AUTHOR]

Previous surveys in Myanmar indicate that soil-transmitted helminths (STH) are a significant public health problem. However the majority of these surveys are small scale or hospital based. To date there has been no countrywide assessment of the prevalence and intensity of STH infection. We conducted a survey (June 2002-June 2003) to assess the magnitude of STH infection in school age children in each of the different ecological areas of the country. In each area, five schools were selected and from each one, 50 children were randomly chosen. Parasitological and nutritional data were collected from each child. We found an overall prevalence of infection of 69%: 18% had a moderate-heavy intensity of infection, 22% were anaemic. A pilot exercise to treat 25 000 school age children in the 200 schools of Nyangdone Township tested the strategy before scaling up and to generate some rough costings. A crude calculation of the expenditure to buy and deliver the drugs, including the costs incurred in the teacher training, concluded that the cost per child was approximately 0.05 USD. [ABSTRACT FROM AUTHOR]

Survival and infectivity of oospores in soils naturally infested with P. infestans oospores were studied in central Mexico. Sporangia were selectively eliminated from soil samples to determine infectivity attributable to the presence of oospores. Selective elimination of sporangia was achieved by two cycles of wetting and drying the soil. Oospore concentration, viability, and infectivity varied among soils collected during the winter fallow in different locations of central Mexico. In some soils, oospores were infective regardless of the time at which they were collected during the winter fallow. However, oospore viability and infectivity decreased following 2 years of intercropping. The number of stem lesions and initial disease severity were significantly higher in soils with moderate (20 to 39 oospores g[sup -1] soil) oospore infestation compared with soils with low (0 to 19 oospores g[sup -1] soil) infestation. Our study confirms that oospores can survive winter fallow and serve as a source of primary inoculum in the central highlands of Mexico. Oospore survival appeared lower in the Toluca Valley soil, which may be an indication of soil suppressiveness. [ABSTRACT FROM AUTHOR]

The rates of transmission of infection from inoculum or infecteds to susceptible hosts are critical determinants of epidemics, yet no formal experimental methods have been described for their quantification and analysis in spatially explicit epidemics. Replicated microcosms of >400 radish seedlings and with tight control of environmental conditions were exposed to known amounts of inoculum of the fungal plant pathogen Rhizoctonia solani. Spatiotemporal maps of disease progress were used to distinguish between primary and secondary infections and to count changes with time in the number of infected plants and the number of contacts between susceptible and neighboring infected plants. Transmission rates were defined within a compartmental S-I (susceptible-infected) model for plant epidemics and estimated empirically using counts from spatial maps. The transmission rate for primary infection declined with time; the transmission rate for secondary infection rose initially and then declined. We discuss the mechanisms contributing to the changes in transmission rates with time and show that spatial mapping combined with an epidemiological analysis provides accurate empirical estimates of transmission rates. [ABSTRACT FROM AUTHOR]

Dry bean root rot, caused by Fusarium solani f. sp. phaseoli, in association with Rhizoctonia solani and Fusarium oxysporum is an increasing problem in Minnesota. A standard seed treatment (SST) (Captan 400+Streptomycin+Lorsban 50) has failed to effectively control the disease and resistant cultivars are unknown. The objectives of this study were to determine the effect of the biocontrol agents Bacillus subtilis strain GBO3 (Kodiak), MBI600 (Epic) and Trichoderma harzianum (T-22) on the incidence and severity of bean root rot; to compare conventional and granular formulations of B. subtilis, and to determine effectiveness of root rot control with co-inoculations of B. subtilis and Rhizobium. Greenhouse studies evaluated the effect of B. subtilis GBO3 and T. harzianum T-22 alone or in combination with Captan 400 and Vitavax 200 as biocontrol treatments in contrast to the SST. Seed application of both B. subtilis GBO3 and T. harzianum T-22 (P>0.05) increased plant biomass and decreased disease severity (DS) under greenhouse conditions. Field experiments were conducted in 1997, 1998 and 1999 in naturally root rot infested fields at Staples and Verndale, MN. In 1997, seed treated with B. subtilis GBO3 reduced bean root rot and increased yield 31%, when compared to untreated plants. Bean seed inoculated with Rhizobium tropici UMR 1899 also increased yield 13% over the untreated control, though neither treatment eliminated disease. In 1998 in a grower’s field with favorable conditions for disease, three of the four treatments that included B. subtilis GBO3 outyielded the untreated control, and SST by 300–800 kg/ha, but in only one treatment were these results statistically significant (P<0.05). In 1999, under severe disease pressure only co-inoculation with B. subtilis MBI600 (Epic) and R. tropici significantly reduced DS and enhanced yield relative to the control and SST treatments. Application of B. subtilis with Rhizobium is a promising approach for the improvement of bean root rot control. [Copyright &y& Elsevier]

Background Pre-school age children (preSAC) remain difficult to reach in mass drug administration (MDA) programmes to control soil-transmitted helminth (STH) infections. Kindergartens provide a unique platform to increase the coverage of MDA in preSAC in Ethiopia, but surveys assessing STHs among preSAC in kindergartens are scarce. Methods We report the prevalence and intensity of STH infections among 622 preSAC in 12 kindergartens in Jimma, Ethiopia. Results STHs were found in all kindergartens, with prevalence exceeding 50% in 8 kindergartens. The majority of the infections were of low intensity. Conclusions This study highlights the importance of kindergartens as an additional opportunity for MDA in Ethiopia. [ABSTRACT FROM PUBLISHER]

Anthrax is an acute disease caused by the bacterium Bacillus anthracis. This bacteria can form dormant endospores. When spores are inhaled, ingested, or come into contact with a skin lesion on a host, they may become reactivated multiply and rapidly. B. anthracis bacterial spores are soil-borne. Because of their long lifespan, spores are present globally and remain at the burial sites of animals killed by anthrax for many decades. Diseased animals can spread anthrax to humans, either by direct contact or by consumption of a diseased animal's flesh. The most frequent clinical type of anthrax is cutaneous anthrax. It presents as a boil-like skin lesion that eventually forms an ulcer with a black center (eschar). Cutaneous anthrax form often within the site of spore penetration between two and five days after exposure. Until the 20th century, anthrax infections killed thousands of animals and people worldwide each year. Animal vaccination programs and antibiotic therapy were decreased the number of deaths. But, anthrax is still a problem in less developed countries. It has been reported that the incidence of disease has decreased in Turkey. However, we present here in three cases of cutaneous anthrax admitted to the emergency department of our hospital within a week. [ABSTRACT FROM AUTHOR]

This article presents a study which shows that soil disturbance reduces the infectivity of external hyphae of vesicular arbuscular mycorrhizal fungi. In the study, two glasshouse experiments has been conducted to determine the effect of soil disturbance on the infectivity of external hyphae of vesicular-arbuscular (VA) mycorrhizal fungi. A nylon mesh was used to exclude plant roots while allowing fungal hyphae to grow into soil contained by the mesh. Hyphae of VA mycorrhizal fungi that had been separated from the original host plant root were still able to colonize bioassay plants rapidly and extensively. However, disturbance of the soil inside the mesh, by mixing for 1 minute, almost eliminated subsequent VA mycorrhiza formation in that soil. Damage to the soil hyphal network by soil disturbance may contribute to the losses in mycorrhizal infectivity that have been observed after mining and cultivation.

The lateral spread in a steamed lateritic podsol of Glomus fasciculatum (Thaxter sensu Gerd.) Gerd. and Trappe from localized inoculum was examined in two pasture species: Trifoliumsubterraneum L. (subterranean clover) and Lolium rigidum Gaud. (Wimmera ryegrass). Mycorrhizal infection was estimated 21, 28, 38 and 59 d after sowing at points 2,4,6,8,10, 14, 20 and 26 cm from the inoculum. The proportion of root length infected by G. fasciculatum at increasing distances from the inoculum could be best described by a Gompertz curve in both plant species at all harvests. Thus the curve had an upper plateau of the maximum percentage of infection. It is suggested that the pattern of spread of G. fasciculatum through roots of subterranean clover and ryegrass is related to changes in the amount of inoculum with distance from the point of inoculation, as well as over time. The rate of spread of the infection front was not constant. Thus it may not be appropriate to calculate mean rates of spread of mycorrhizal fungi over long time periods. [ABSTRACT FROM AUTHOR]

The effect of root density on the spread of vesicular-arbuscular mycorrhizal infection was measured using Trifolium repens (clover) and Festuca rubra (fescue). Seeds of both host species were sown in large troughs at three different distances apart, which resulted in different root densities that persisted for up to 15 weeks. For clover, colonization (i.e. total length of infected root) and linear spread were favoured by greater root densities, and at the greatest root density colonization seemed to proceed faster than root extension. In fescue, root density was positively related to linear spread up to about 23 cm root cm-3 soil, but greater root density was supraoptimal for linear spread but not for colonization. Although root density had important effects on the spread of infection, effects of plant species were much greater. Fescue had more total root (five times that of clover), but it supported less linear spread and less than half the total length of infected root. [ABSTRACT FROM AUTHOR]

The effects of vesicular-arbuscular (VA) mycorrhizal association on the growth of Festuca ovina L. were assessed in soils sterilized by irradiation, in unsterilized soil, and in sand-peat cultures with various nutrients additions. In irrdiated soils, effects of mycorrhizal infection were masked by nutrient release which proceeded through the first 4 months of growth. However, 9 months after inoculation, significant increases of yield and phosphorus content occurred in the mycorrhizal plants. When the irradiated soil was recovered and reused to grow a second crop, marked increases of yield and P content were observed in mycorrhizal plants. Growth in unsterilized field soil was very slow despite the fact that all the plants were heavily infected, In sand culture, mycorrhizal plants were not significantly larger than non-mycorrhizal controls when both were supplied with a full nutrient medium but differences between the two categories were evident when sand-peat mixtures were supplemented with dilute nutrient medium and water. The results are discussed in relation to the possible significance of mycorrhizal infection in the field, [ABSTRACT FROM AUTHOR]

Presents a study on the ex-situ process for treating PAH-contaminated soil with phanerochaete chrysosporium by the designing of a fungal reactor system. Information on the method used to extract soil; Examination on the reduction of total soil PAH by use of fungus; Information on the results weight polymers found in soil.

The effects of soil temperature on infection of sugar-beet roots by the soil-borne fungus Polymyxa betae were investigated in controlled environments. Pre-germinated seeds were sown in pots of naturally infested soil and seedlings sampled at frequent intervals over a period of several weeks. Within the range 10–30°C, the optimum soil temperature for infection was c. 25°C; the time between sowing and the first detectable infection was shortest and the subsequent rate of infection most rapid at this temperature. No infection was observed over 80 days at 1O°C. Both root and shoot dry weight were reduced on plants growing in infested soil at 15, 20 and 25°C compared with those growing in uninfested soil. In general, root growth was more severely affected than shoot growth and the effects were most pronounced at 20°C. These results were confirmed in a subsequent experiment in which P. betae-infected root material was used as the inoculum. In addition to its role as the vector of beet necrotic yellow vein virus (the cause of Rhizomania disease), the significance of P. betae as a plant pathogen in its own right is discussed. [ABSTRACT FROM AUTHOR]

A soil-borne virus with rod-shaped particles (700-750 × 12 nm) was isolated from oats. It was transmitted with difficulty by sap inoculation to oats, but not to nine other species of Gramineae nor to Chenopodium amaranticolor. Two distinct strains of the virus were found; one causing chlorotic or ash-grey eyespots with dark green centres to appear on the basal portion of the oldest leaves and the other a general mottling of the upper portion of the youngest leaves. It is concluded that the virus is similar to, and probably identical with, oat mosaic virus in the United States. [ABSTRACT FROM AUTHOR]

The article describes the mechanism by which the prison disease, chronic wasting disease (CWD), is laterally transmitted to deer, elk and moose populations. Prions, which comprised of a misfolded isoform of the normal prion protein, PrPC, into the infectious conformation, are released into the environment and interact with quartz sands and soils. Studies which examined the role of soil on prion infectivity through protein misfolding cyclic amplification (PMCA) are cited.

The virus in naturally infected, stunted triticale plants was identified as soil-borne wheat mosaic virus ( SBWMV). The infected plants were collected in the Southern Wielkopolska region ( Western Poland). Molecular analysis including RT- PCR, and sequencing of the complete coding sequence of coat protein gene, was performed. The sequence of the Polish isolate of SBWMV ( SBWMV-Pol1) shared 100, 99 and 98% identities with the corresponding regions of De1 ( AF519799), OKL-1 ( X81639) and US- Nebraska ( L07938) isolates of SBWMV, respectively. Phylogenetic analyses showed that the Polish isolate, SBWMV- Pol1, clustered together with other SBWMV isolates. This is the first report of the occurrence of SBWMV in Poland and the second of its presence in Europe. [ABSTRACT FROM AUTHOR]

Abstract: The Kato-Katz thick smear technique is widely used to assess prevalence and intensity in soil-transmitted helminth (STH) control programmes, but its usefulness in monitoring anthelminthic drug efficacy needs to be validated and compared with other methods. A promising alternative is the McMaster egg counting technique. In the present study, the efficacy of single-dose albendazole against STH infections in 430 schoolchildren on Pemba Island was assessed using both the Kato-Katz and McMaster techniques. The study revealed comparable drug efficacy results for both methods and confirmed the potency of the McMaster technique as an alternative method for monitoring large-scale deworming programmes. [Copyright &y& Elsevier]

Cryptococcus neoformans is an encapsulated yeast that can cause cryptococcosis, a life-threatening infection that mainly occurs in immunocompromised patients. The major environmental sources of C. neoformans have been shown to be soil contaminated with avian droppings. In the present study, we evaluated the isolation of C. neoformans from swallow (Hirundo rustica) excreta in two northern cities of Iran. Ninety-seven swallow droppings were evaluated and 498 yeast-like colonies were isolated and identified as Rhodotorula spp. (62.8%), Candida spp. (28.5%) and C. neoformans (8.7%). Cryptococcus neoformans was isolated from 5/97 (5.2%) of collected samples. Min-Max colony forming units (CFU) per one gram for the positive samples were 3-10 C. neoformans colonies. The total mean CFU per one gram for the positive samples was 4.8. The results of this study demonstrate that excreta of swallow may harbor different species of potentially pathogenic yeasts, mainly C. neoformans, and may be capable of disseminating these fungi in the environment. [ABSTRACT FROM AUTHOR]

The article provides information regarding the incidence of infection, clinical presentations, diagnosis, treatment and prevention of listeriosis. Listeria monocytogenes, the microbe which causes listeriosis, can grow in anaerobic or aerobic conditions and are usually found in soil, decaying vegetation and water, and may be part of the fecal flora of many mammals. It states that the incidence of listeriosis is difficult to establish because symptoms may be mistaken for a flu-like illness. Flu-like symptoms, nausea, vomiting, cramps, diarrhea and fever are the initial symptoms of infection. Furthermore, a list of information which are provided to health care professionals and to the general public by the Public Health Agency of Canada is presented.

Helminthic diseases can be found worldwide, and the prevalence of helminthiases was also found to be closely associated with climatic and geographical factors. Soil-transmitted helminth infections are among the most prevalent of chronic human infections worldwide. Based on the demonstrable impact on child development, there is a global commitment to finance and implement control strategies with a focus on school-based chemotherapy programs. Children in the developing countries become the most important vulnerable group to these infections. The main reason is that they usually play within the grounds. Here, the authors summarize experience on previous reports on the soil-transmitted parasite contamination in Thailand. Also, the authors discuss the problem of soil-transmitted parasites as still being an important problem. [ABSTRACT FROM AUTHOR]

Abstract: Toxocara species ova were found in 16 of 146 (11 per ¢) soil samples collected from backyards and gardens of private residences within Baltimore City. The recovery rate of parasite ova was similar for households regardless of their grouping by pet ownership characteristics or the presence of visible animal feces. The findings demonstrate the common occurrence of these eggs in locations likely to be important in the transmission of visceral larva migrans. (Am J Public Health 1985; 75:1092-1094.) [ABSTRACT FROM AUTHOR]

This article discusses the infection being brought by parasitic helminths, or worms, to humans. Most of these worms spend a portion of their life cycle in the soil and infect man from there. The classifications of helminths parasitic to man based on the manner of transmission are contagious or fecal-borne, soil-transmitted geohelminths, Arthropod-transmitted, snail-transmitted, and food-animal-transmitted. Clinical manifestations of helminthic infestations vary widely, depending upon the worm load, the lodgments of the worms, and other factors.

Phytophthora cinnamomi, responsible for "root rot" or "dieback" plant disease, causes a significant amount of economic and environmental impact. In this work, the fungicide action of nanocomposites based on silver nanoparticles and polyphenol inclusion compounds, which feature enhanced bioavailability and water solubility, was assayed for the control of this soil-borne water mold. Inclusion compounds were prepared by an aqueous two-phase system separation method through extraction, either in an hydroalcoholic solution with chitosan oligomers (COS) or in a choline chloride:urea:glycerol deep eutectic solvent (DES). The new inclusion compounds were synthesized from stevioside and various polyphenols (gallic acid, silymarin, ferulic acid and curcumin), in a [6:1] ratio in the COS medium and in a [3:1] ratio in the DES medium, respectively. Their in vitro response against Phytophthora cinnamomi isolate MYC43 (at concentrations of 125, 250 and 500 µg·mL−1) was tested, which found a significant mycelial growth inhibition, particularly high for the composites prepared using DES. Therefore, these nanocomposites hold promise as an alternative to fosetyl-Al and metalaxyl conventional systemic fungicides. [ABSTRACT FROM AUTHOR]

Reports on the effect of the deadly tropical infections called melioidosis, which has been ignored in Thailand. Tendency to be used as a biological weapon; Diagnosis of the infection; Risk factors of the disease.

Explores worldwide trends in medical helminthology. Types of soil-transmitted helminths and schistosomes. 54th World Health Assembly's approval of resolution WHA54.19 which calls to support a global assault againsts heminths and schistosomes; Worm eradication programs; Research programs for medical helminthology.

The successful colonization of plant growth promoting rhizobacteria (PGPR) in the rhizosphere is an initial and compulsory step in the protection of plants from soil-borne pathogens. Therefore, it is necessary to evaluate the role of root exudates in the colonization of PGPR. Banana root exudates were analyzed by high pressure liquid chromatography (HPLC) which revealed exudates contained several organic acids (OAs) including oxalic, malic and fumaric acid. The chemotactic response and biofilm formation of Bacillus amyloliquefaciens NJN-6 were investigated in response to OA's found in banana root exudates. Furthermore, the transcriptional levels of genes involved in biofilm formation, yqxM and epsD, were evaluated in response to OAs via quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Results suggested that root exudates containing the OAs both induced the chemotaxis and biofilm formation in NJN-6. In fact, the strongest chemotactic and biofilm response was found when 50 μM of OAs were applied. More specifically, malic acid showed the greatest chemotactic response whereas fumaric acid significantly induced biofilm formation by a 20.7-27.3% increase and therefore biofilm formation genes expression. The results showed banana root exudates, in particular the OAs released, play a crucial role in attracting and initiating PGPR colonization on the host roots. [ABSTRACT FROM AUTHOR]

Passiflora pohlii Mast. (Passifloraceae) is a wild species native to Brazil, with a potential agronomic interest due to its tolerance to soil-borne pathogens that cause damage to the passion fruit culture. Because this species occurs in impacted regions, the goal of this study was the development of an efficient cryopreservation strategy for nodal segments excised from axenic plants using vitrification-based methods. The genetic stability of the recovered plants was also evaluated by RAPD and ISSR. In the encapsulation–vitrification protocol, precultured explants on medium with high sucrose concentrations (0.3–0.7 M) were encapsulated in calcium alginate beads, followed by incubation in liquid 1/2MSM medium with 0.75 M sucrose for 24 h. After this, beads were exposed to PVS2 or PVS3 for different periods before immersion into LN. In the vitrification protocol, precultured explants were incubated in the cryoprotectant solutions and stored in LN using the same conditions adopted for encapsulation–vitrification. Frozen materials were rewarmed at 40 °C and transferred to the recovery medium (MSM supplemented with 30.8 μ M BA). Explants were kept in the dark for 30 or 60 days before transfer to the presence of light. Although plant recovery was achieved using both vitrification-based protocols, higher recovery rates were obtained with the vitrification technique, when explants were incubated in the dark. RAPD and ISSR analyses indicated that shoots derived from cryopreserved explants were genetically stable at the genomic regions tested. These results show that cryopreservation of nodal segments through the vitrification technique can be used for long-term storage of P. pohlii germplasm. [ABSTRACT FROM AUTHOR]

Nocardia species are ubiquitous soil-borne organisms that most commonly cause invasive disease in patients with defective cell-mediated immunity. We report a case of recurrent Nocardia sepsis in a patient with sickle cell disease and chronic iron overload, who was undergoing high-dose infusions of deferoxamine through a central venous catheter. [ABSTRACT FROM PUBLISHER]

Co-infection is ubiquitous in people in the developing world but little is known regarding the potential for one parasite to act as a risk factor for another. Using generalized linear mixed modelling approaches applied to data from school-aged children from Zanzibar, Tanzania, we determined the strength of association between four focal infections (i.e. Ascaris lumbricoides, Trichuris trichiura, hookworm and self-reported fever, the latter used as a proxy for viral, bacterial or protozoal infections) and the prevalence or intensity of each of the helminth infections. We compared these potential co-infections with additional risk factors, specifically, host sex and age, socioeconomic status and physical environment, and determined what the relative contribution of each risk factor was. We found that the risk of infection with all four focal infections was strongly associated with at least one other infection, and that this was frequently dependent on the intensity of that other infection. In comparison, no other incorporated risk factor was associated with all focal infections. Successful control of infectious diseases requires identification of infection risk factors. This study demonstrates that co-infection is likely to be one of these principal risk factors and should therefore be given greater consideration when designing disease-control strategies. Future work should also incorporate other potential risk factors, including host genetics which were not available in this study and, ideally, assess the risks via experimental manipulation. [ABSTRACT FROM AUTHOR]