Isolation of salmonella bacteriophages from swine effluent lagoons

Bacteriophages (phages) associated with Salmonella were collected from nine swine manure lagoons in Mississippi. Phages were isolated by an enrichment protocol or directly from effluent. For enrichment, chloroform-treated samples were filtered (0.22 mum) and selectively enriched by adding a cocktail of Salmonella strains in trypticase soy broth. After overnight incubation at 35 degrees C, chloroform was added and samples stored at 5 degrees C. Enriched samples were tested by double agar layer (DAL) plaque assay against individual Salmonella isolates. Phage titers of 2.9 x 10(8) to 2.1 x 10(9) plaque forming units (pfu) per mL were produced, but estimation of phage titers in lagoons was not possible. For direct isolation, effluent was clarified by centrifugation, filtered (0.22 microm), and used in DAL plaque assays to select single-plaque isolates for 15 Salmonella strains. Plaque counts varied among Salmonella strains and lagoons. The most sensitive strain for direct phage recovery was ATCC 13311. Phage titers estimated by direct isolation with ATCC 13311 ranged among lagoons from 12 to 148 pfu per mL. In limited host range tests, 66 isolates recovered by the enrichment protocol produced plaques only on Enteritidis and Typhimurium strains of Salmonella and none produced plaques on lagoon isolates of Citrobacter, Escherichia, Proteus, Providencia, or Serratia. Electron microscopy (EM) showed purified enrichment isolates had Podoviridae morphology (tailless 50-nm icosahedral heads with tail spikes). Electron microscopy of clarified concentrated effluent showed 5.5:1 tailless to tailed phages. The isolated phages have potential as typing reagents, specific indicators, and biocontrol agents of Salmonella.

Polarity and temporality of high-resolution y-chromosome distributions in India identify both indigenous and exogenous expansions and reveal minor genetic influence of Central Asian pastoralists

Although considerable cultural impact on social hierarchy and language in South Asia is attributable to the arrival of nomadic Central Asian pastoralists, genetic data (mitochondrial and Y chromosomal) have yielded dramatically conflicting inferences on the genetic origins of tribes and castes of South Asia. We sought to resolve this conflict, using high-resolution data on 69 informative Y-chromosome binary markers and 10 microsatellite markers from a large set of geographically, socially, and linguistically representative ethnic groups of South Asia. We found that the influence of Central Asia on the pre-existing gene pool was minor. The ages of accumulated microsatellite variation in the majority of Indian haplogroups exceed 10,000-15,000 years, which attests to the antiquity of regional differentiation. Therefore, our data do not support models that invoke a pronounced recent genetic input from Central Asia to explain the observed genetic variation in South Asia. R1a1 and R2 haplogroups indicate demographic complexity that is inconsistent with a recent single history. Associated microsatellite analyses of the high-frequency R1a1 haplogroup chromosomes indicate independent recent histories of the Indus Valley and the peninsular Indian region. Our data are also more consistent with a peninsular origin of Dravidian speakers than a source with proximity to the Indus and with significant genetic input resulting from demic diffusion associated with agriculture. Our results underscore the importance of marker ascertainment for distinguishing phylogenetic terminal branches from basal nodes when attributing ancestral composition and temporality to either indigenous or exogenous sources. Our reappraisal indicates that pre-Holocene and Holocene-era--not Indo-European--expansions have shaped the distinctive South Asian Y-chromosome landscape.

Low seroprevalence of antibodies to Neospora caninum in wild canids in Israel

The role of domestic dogs in the epidemiology of Neospora caninum as well as the relationship between N. caninum infection of farm dogs and cattle were demonstrated, however, evidence is scarce regarding the role of wild canids in domestic animal neosporosis. The present study was undertaken to evaluate the role of wild canids in the epidemiology of bovine neosporosis in Israel by analyzing the prevalence of antibodies to N. caninum in wild canids. Sera samples were collected from 114 free ranging wild golden jackals (Canis aureus), 24 red foxes (Vulpes vulpes) and nine wolves (Canis lupus), which were collected in Israel during the years 1999-2004. Of a total of 147 wild canids tested antibodies to N. caninum were only found in two golden jackals with IFAT titers of 1:50, and in one red fox and one wolf with IFAT titer of 1:400. The low seroprevalence found in this study (2.7%) indicated that wild canids probably do not have an important role in the epidemiology of N. caninum in Israel. However, since the diet of different species of wild canids and even diverse populations of the same canid species vary, it is possible that other results might be obtained from specific wild canids populations, which scavenge in the vicinity of infected bovines.

Rabies vaccination programme for red foxes (Vulpes vulpes) and golden jackals (Canis aureus) in Israel (1999-2004)

Since 1956, red foxes (Vulpes vulpes) and, to a lesser extent, golden jackals (Canis aureus), have been the primary vectors maintaining endemic wildlife rabies in Israel. Starting in the autumn of 1998, oral rabies vaccination campaigns have been conducted in Israel targeting these two wildlife species, with increasing yearly geographical extension. Significant data have been accumulated from an area of approximately 5,200 km2 in Northern Israel. In the spring of 2003 the project was extended to 14,000 km2 and in the autumn to 21,000 km2, covering almost all inhabited areas in Israel and the West Bank. A total of two million RABORAL V-RG (Merial) vaccine-filled baits were distributed bi-annually by plane or helicopter at 14-19 baits km2. Since the onset of oral vaccination activities in 1998, annual bait acceptance in the vaccination zones has been demonstrated by biomarker detection (with tetracycline) in 55 % (429/783) of bone samples of target animals submitted for diagnosis. In 1999 to 2004, vaccine contact and induction of immunity in animals collected from the vaccination zones were reflected by seroconversion in 66 of 284 animals (23 %). By the year 2004, rabies cases declined sharply in all progressively vaccinated areas.

Xenon measurement in breathing systems: a comparison of ultrasonic and thermal conductivity methods

Xenon is an anaesthetic and possibly neuroprotective gas that is impossible to measure using conventional anaesthetic gas analysers. We compared the performance of two commissioned xenon analysers using ultrasonic and thermal conductivity principles against a reference method of laser refractometry. An experimental gas circuit was constructed and xenon concentrations compared over a range of 0-100% in oxygen. Eighty-two paired measurements were made comparing the experimental methods with laser refractometry. The ultrasonic method displayed good agreement with laser refractometry, with a mean difference of - 0.74% and two standard deviation limits of agreement of + 1.08% to - 2.56%. The agreement between laser refractometry and thermal conductivity was poor, the mean difference being - 5.37%, with two standard deviation limits of agreement of + 0.6% to - 11.3%. The ultrasonic method for measuring xenon concentrations can be used in breathing circuits. The thermal conductivity instrument may need further development.

Lysosomal responses as a diagnostic tool for the detection of chronic petroleum pollution at Todos os Santos Bay, Brazil

Coastal marine environments, especially semienclosed systems such as bays, are under unrelenting stress caused by urban and industrial development. Biomonitoring plays a vital role in strategies to identify, assess, and control stressors. However, due to the magnitude of the challenge there is a demand for new and innovative approaches to provide timely and accessible information to environmental managers and policy makers. The present work aimed to assess hydrocarbon levels in sediments from petroleum-related industrial areas at Todos os Santos Bay (Brazil) and associate them to toxicity-induced responses (neutral red retention (NRR) assay) by the burrowing clam Anomalocardia brasiliana. Surface sediments collected during the dry and rainy seasons were analyzed for aliphatic and aromatic hydrocarbons. At the control site, hydrocarbon levels were low and mainly biogenic. The aliphatic hydrocarbon ("total unresolved complex mixture," alkanes, and isoprenoids) concentrations indicated a chronic situation with very little "fresh" oil contamination at the oil-related sites. The polycyclic aromatic hydrocarbons indicated sites moderately contaminated by chronic oil and some pyrolytic input. The effects of those contaminants were assessed by the lysosomal NRR assay applied to A. brasiliana hemocytes. Sediment toxicity at the oil-related sites was evidenced by the lowered capacity of the lysosomes to retain the neutral red dye compared to results from the control site. This research indicates that the NRR assay is a useful and efficient screening technique able to discriminate polluted from clean sites.

Lentiginous melanoma: a histologic pattern of melanoma to be distinguished from lentiginous nevus

Atypical lentiginous melanocytic proliferations in elderly patients continue to pose a diagnostic dilemma with lesions variably categorized as dysplastic nevus, atypical junctional nevus, melanoma in situ (early or evolving) and premalignant melanosis. We present pigmented lesions from 16 patients (seven male and nine female) and with the exception of one case, all were older than 50 years of age. The anatomical sites included trunk (7), head and neck (6) and upper extremity (3). The clinical diagnosis was variable and included lentigo maligna, atypical nevus, pigmented basal cell carcinoma, seborrheic keratosis and lentigo. The initial biopsies mimicked lentiginous nevus or dysplastic nevus and were characterized by a lentiginous proliferation of melanocytes at the dermoepidermal junction both as single cells and as small nests with areas of confluent growth, extending to the edges of the biopsy. The retiform epidermis was maintained and pagetoid spread of melanocytes was not prominent in hematoxylin- and eosin- stained sections. Dermal fibrosis was variably present and the melanocytic proliferation demonstrated cytological atypia. The subsequent re-excisions demonstrated similar atypical melanocytic proliferation occurring over a broad area flanking the prior biopsy sites. The diagnosis of melanoma was more easily recognized in the complete excision specimens. Immunohistochemical stains for Mitf and Mart-1 highlighted the extent of the basalar melanocytic proliferation as well as foci of pagetoid spread by melanocytes. Familiarity with this pattern of early melanoma should facilitate proper classification of lentiginous melanocytic proliferations in biopsies from older adults.

Haematological and biochemical measurements in healthy, adult, free-ranging golden jackals (Canis aureus syriacus) held in captivity

Blood from 31 healthy, free-ranging golden jackals held in captivity for seven days was collected while they were anaesthetised. Haematological and serum biochemical measurements were analysed and the 95 per cent confidence interval for each variable was compared with the reference value for domestic dogs. The measurements of their red blood cells were within the reference interval for dogs, but the jackals had higher white blood cell counts and eosinophil counts than dogs. The male jackals had a higher haematocrit, red blood cell count, mean corpuscular volume and mean corpuscular haemoglobin concentration, and a lower red blood cell distribution width than the female jackals. High activities of muscle enzymes were detected in many of the jackals, in several of which the activity of creatine kinase exceeded 5000 U/l; these were considered abnormal.

Melanocytic lesions associated with dermatofibromas: a spectrum of lesions ranging from junctional nevus to malignant melanoma in situ

Dermatofibromas are common lesions that are often associated with epidermal hyperplasia and basal layer hyperpigmentation. A single case of lentiginous melanocytic hyperplasia overlying a dermatofibroma has been reported, however, nevi and melanoma have to the best of our knowledge, not been previously reported. We present 14 cases of melanocytic lesions associated with dermatofibromas. The clinical data and hematoxylin- and eosin- stained sections were obtained and formalin-fixed, paraffin-embedded tissue was immunostained with antibodies against S-100, Mart-1, Factor XIIIa, and CD117. There were nine females and five males ranging in age from 30 to 64 years and anatomic sites included back (five), arm (six), flank (two), and leg (one). The clinical diagnosis ranged from dermatofibroma to desmoplastic melanoma. Histologically, the melanocytic lesions included junctional, compound, and dermal nevi, and malignant melanoma in situ. In four cases the dermal component appeared to merge with the dermatofibroma. In the case of the melanoma in situ, the dermatofibroma abutted the epidermis. Immunohistochemically, the melanocytic lesions were S-100/ Mart-1+, FXIIIa-, and the dermatofibromas were S-100/Mart-1-, FXIIIa+. Melanocytic neoplasia may appear in association with dermatofibromas. The fibrohistiocytic proliferation may be misinterpreted as a spindle or pleomorphic melanocytic process. Awareness of this association will aid in the correct diagnosis, and immunohistochemical studies will help in the differentiation of these two cell populations.

Malignant mesothelioma with a pronounced myxoid stroma: a clinical and pathological evaluation of 19 cases

Mesothelioma with a pronounced myxoid stroma has been identified as a morphological pattern that might portend a better prognosis. Reports on this type of cases are few. Its clinical and pathological features are not defined. In this study, we identified 19 such cases from a series of 234 pleural mesotheliomas and performed a comprehensive clinical and pathological analysis. The inclusion criteria were mesotheliomas with at least 50% of the tumor exhibiting a pronounced myxoid stroma that occupied more than 50% of the tumor volume (designated as myxoid mesothelioma). There were ten males and nine females, with a median age of 58 years. Forty seven percent of the patients had probable or definite asbestos exposure. Patients presented at various stages [International Mesothelioma Interest Group (IMIG) stage II, 4; stage III, 9; and stage IV, 6]. Most (16/19) patients were treated by extrapleural pneumonectomy with adjuvant radiation or chemotherapy or both. Overall, the median survival rate was 36 months (median follow-up time, 17 months), and the 2-year survival rate was 79%. Histologically, the tumor cell component was entirely epithelioid without significant cytologic atypia. The myxoid material stained positive for Alcian blue, and the staining diminished after treatment with hyaluronidase in 12 of 12 cases. The tumor cells showed a typical mesothelial immunophenotype. Ultrastructurally, all six tumors examined had typical mesothelial-type surface microvilli and a moderately electron-dense extracellular amorphous material that often formed a haze enmeshing the surface microvilli. Hyaluronic acid-type, fern-like crystals were noted in all cases. These findings show that myxoid mesotheliomas represent a group of epithelioid mesotheliomas that have retained the secretory activity of normal mesothelium. Patients may present at different stages, but survival appears to be superior to that of epithelioid mesotheliomas in general. Our study emphasizes the need for better attention to histologic subtypes, particularly in the context of prognostically or therapeutically oriented investigations of this lethal disease.

Blurring the boundaries: scenario-based simulation in a clinical setting

CONTEXT

The ability to perform clinical procedures safely is a key skill for health care professionals. Performing such procedures on conscious patients is challenging and requires a combination of technical and communication skills. We have developed quasi-clinical scenarios, where inanimate models attached to simulated patients provide a convincing learning environment. Procedures are rated by expert observers and by the 'patient' and recorded for subsequent review. This study explores the potential of locating such scenarios within a real clinical setting, allowing participants to experience the challenges of the workplace while ensuring patient safety. An innovative portable digital recording device (the 'Virtual Chaperone') is evaluated for use in clinical settings.

METHODS

A qualitative design (observation and interview studies) investigated volunteer medical students undertaking 2 procedure scenarios (insertion of urinary catheter and wound closure with sutures) within the accident unit of a large London hospital. All procedures were observed in real time and recorded digitally (using the Virtual Chaperone). A protocol was used for structured feedback. Observational and interview data was analysed using standard qualitative techniques.

RESULTS

Seven sessions with 22 undergraduate medical students took place over 9 months within 1 centre. Data confirmed the feasibility of using a moveable, self-contained training scenario within an authentic clinical setting. Overall, the response from participants was positive.

CONCLUSION

Scenario-based teaching within an authentic clinical environment is feasible and perceived by participants to be educationally useful. This approach blurs traditional boundaries between skills laboratory teaching and clinical practice and may offer considerable advantages in training for clinical procedures.

Outcome of unrelated transplants in patients with multiple myeloma

The outcome of patients with multiple myeloma treated with standard therapy is disappointing, with a historical median survival of 3 years. Although high-dose therapy with autologous stem cell transplant has improved treatment outcomes, cure is unlikely. Allogeneic transplant provides a tumor-free graft and a graft-versus-myeloma effect. However, only a minority of patients has a compatible sibling donor. Unrelated hematopoietic stem cell transplant is another option. We analyzed the outcome of patients who received an unrelated bone marrow transplant facilitated by the National Marrow Donor Program (NMDP). Between 1989 and 2000, 71 patients received a myeloablative unrelated transplant for multiple myeloma; 70 patients consented for this analysis. The median recipient age was 44 years. A total of 31% of patients had received a prior autologous transplant. In all, 91% of patients engrafted. The 3-year cumulative incidence estimate of relapse was 34+/-10%. The incidence of Grade II-IV GVHD was 47%. The Kaplan-Meier estimate for overall survival at 5 years was 9+/-7%. The 100-day treatment-related mortality was 42%. In multivariate analysis, only a male donor was a significant predictor for survival. Better strategies are needed to treat patients with multiple myeloma, perhaps by using less-toxic, nonmyeloablative conditioning regimens.

Is Open Access to medical research literature relevant to low- and middle-income countries?

At the end of 2003, the United Nations held the first phase of the World Summit on the Information Society, the aim of which is to develop a better understanding of the international impact of the information and communication technology revolution. Part of the first meeting's declaration referred to the Open Access movement. This article describes what Open Access is, its implications for medical research in low- and middle-income (LAMI) countries, and considers whether Open Access will make a difference.

Effects of cyclic steroid hormone replacement on prolactin and luteinizing hormone surges in female rats

The ability of steroid hormones to produce an LH or prolactin (PRL) surge was determined in rats ovariectomized at 6, 9 or 13 weeks of age and subjected to one, three or six cycles of estrogen and progesterone replacement. Sensitivity to steroid replacement was dependent on the age of the animal at the time of ovariectomy. Repeated cyclic steroid hormone replacement significantly increased the magnitude of the PRL response, but not the LH response, in animals ovariectomized at 6 weeks. The LH response was significantly altered by cyclic steroid replacement only in animals ovariectomized at 13 weeks. These results indicate that the mechanisms involved in the regulation of PRL secretion are influenced by steroid hormone replacement and that cyclic steroid hormone exposure increases the magnitude of the PRL secretory response.

Phylogeography of Y-chromosome haplogroup I reveals distinct domains of prehistoric gene flow in europe

To investigate which aspects of contemporary human Y-chromosome variation in Europe are characteristic of primary colonization, late-glacial expansions from refuge areas, Neolithic dispersals, or more recent events of gene flow, we have analyzed, in detail, haplogroup I (Hg I), the only major clade of the Y phylogeny that is widespread over Europe but virtually absent elsewhere. The analysis of 1,104 Hg I Y chromosomes, which were identified in the survey of 7,574 males from 60 population samples, revealed several subclades with distinct geographic distributions. Subclade I1a accounts for most of Hg I in Scandinavia, with a rapidly decreasing frequency toward both the East European Plain and the Atlantic fringe, but microsatellite diversity reveals that France could be the source region of the early spread of both I1a and the less common I1c. Also, I1b*, which extends from the eastern Adriatic to eastern Europe and declines noticeably toward the southern Balkans and abruptly toward the periphery of northern Italy, probably diffused after the Last Glacial Maximum from a homeland in eastern Europe or the Balkans. In contrast, I1b2 most likely arose in southern France/Iberia. Similarly to the other subclades, it underwent a postglacial expansion and marked the human colonization of Sardinia approximately 9,000 years ago.

Transient claw hand owing to a bee sting. A report of two cases

We describe two patients with claw hand as a result of a bee sting. It is likely that this was caused by the apamin in the sting which has an effect on the upper limb, at the spinal cord and on the peripheral nerves. It is important to recognise that the claw hand is not owing to compartment syndrome. Both patients were treated conservatively with full resolution within 48 hours, without any lasting effects.

Origin, diffusion, and differentiation of Y-chromosome haplogroups E and J: inferences on the neolithization of Europe and later migratory events in the Mediterranean area

The phylogeography of Y-chromosome haplogroups E (Hg E) and J (Hg J) was investigated in >2400 subjects from 29 populations, mainly from Europe and the Mediterranean area but also from Africa and Asia. The observed 501 Hg E and 445 Hg J samples were subtyped using 36 binary markers and eight microsatellite loci. Spatial patterns reveal that (1). the two sister clades, J-M267 and J-M172, are distributed differentially within the Near East, North Africa, and Europe; (2). J-M267 was spread by two temporally distinct migratory episodes, the most recent one probably associated with the diffusion of Arab people; (3). E-M81 is typical of Berbers, and its presence in Iberia and Sicily is due to recent gene flow from North Africa; (4). J-M172(xM12) distribution is consistent with a Levantine/Anatolian dispersal route to southeastern Europe and may reflect the spread of Anatolian farmers; and (5). E-M78 (for which microsatellite data suggest an eastern African origin) and, to a lesser extent, J-M12(M102) lineages would trace the subsequent diffusion of people from the southern Balkans to the west. A 7%-22% contribution of Y chromosomes from Greece to southern Italy was estimated by admixture analysis.