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Larvae belonging to five species of Hypoderma spp. (Diptera, Oestridae) cause myiasis in wild and domestic ruminants that is characterized by migrations within deep tissues. In China hypodermosis is one of the most important arthropod diseases affecting ruminants and, moreover, represents a significant zoonosis, with numerous reports of Hypoderma spp. affecting farmers. Recently, a sixth species, Hypoderma sinense Pleske, has been rediscovered but the endogenous migration pathway within the host body is completely unknown and it represents a major constraint for the control of larval infection. In December 2003 a total of 165 larval stages of Hypoderma spp. were collected from different anatomical sites of 40 yaks slaughtered at an abattoir in the province of Gansu, China. The morphological characters and size of the recovered larvae were used to infer migratory routes and 45 specimens were also subjected to a polymerase chain reaction (PCR) assay of cox1 mtDNA and amplicons sequenced. All the larvae molecularly processed were identified as H. sinense and sequence identity was confirmed by a PCR-restriction fragment length polymorphism (PCR-RFLP) tool carried out using BfaI and HinfI endonucleases. The finding of H. sinense larvae only in the oesophagus or both in oesophagus and subcutaneous tissue of 12 and 15 animals, respectively, indicates that H. sinense larvae migrate through the oesophagus similarly to Hypoderma lineatum (De Villers). The description of the endogenous life cycle of H. sinense will help to determine the timing of specific treatment programmes to guarantee the improvement of animal welfare and health, thus resulting in an increase in livestock production in China. [ABSTRACT FROM AUTHOR]

Extracranial metastasis from high-grade glial tumors is an extremely rare condition with its reported incidence being <1%. The most common sites reported in the literature are leptomeninges and spinal cord, followed by the liver, lung, and skeletal system. Its low incidence is thought to be related to the intrinsic aggressive biology of the tumor, thus reducing median overall survival in patients. As there is lack of knowledge about the mechanism of extracranial spread of glioma cells, its diagnosis and management remain a major challenge. We report two cases of extracranial metastases from glial tumors to cervical nodes and postoperative site involving preauricular region detected on F18 Fluoro ethyl tyrosine (FET) positron emission tomography-computed tomography and later on confirmed with histopathology Fluoro ethyl tyrosine. [ABSTRACT FROM AUTHOR]

Forensic entomology could provide valuable data for the minimum postmortem interval (PMImin) estimation and other relevant information, such as causes and circumstances of death. Some representatives of flesh flies are one of the dominant necrophagous insects during early stages of decomposition, demonstrating unique biological characteristics compared with other necrophagous flies. Moreover, they lead to global health concerns as carriers of various pathogenic micro-organisms, and dominantly result in the traumatic myiasis. Thus, sarcophagid flies are considered important in decomposition processes for PMImin estimation. However, the utility of sarcophagid flies has been seriously hampered by limited ecological, biological and taxonomic knowledge of them. The aim of this paper is to provide a brief review on the species, distribution and biological habit of forensically important sarcophagid flies. In addition, the relation between traumatic myiasis and flesh flies, molecular identification methods and developmental pattern of flesh flies are summarized. [ABSTRACT FROM AUTHOR]

The skin secretion of many amphibians contains peptides that are able to kill a broad range of microorganisms (antimicrobial peptides: AMPs) and potentially play a role in innate immune defense. Similar to the toxin arsenals of various animals, amphibian AMP repertoires typically show major structural variation, and previous studies have suggested that this may be the result of diversifying selection in adaptation to a diverse spectrum of pathogens. Here we report on transcriptome analyses that indicate a very different pattern in the dwarf clawed frog H. boettgeri. Our analyses reveal a diverse set of transcripts containing two to six tandem repeats, together encoding 14 distinct peptides. Five of these have recently been identified as AMPs, while three more are shown here to potently inhibit the growth of gram-negative bacteria, including multi-drug resistant strains of the medically important Pseudomonas aeruginosa. Although the number of predicted peptides is similar to the numbers of related AMPs in Xenopus and Silurana frog species, they show significantly lower structural variation. Selection analyses confirm that, in contrast to the AMPs of other amphibians, the H. boettgeri peptides did not evolve under diversifying selection. Instead, the low sequence variation among tandem repeats resulted from purifying selection, recent duplication and/or concerted gene evolution. Our study demonstrates that defense peptide repertoires of closely related taxa, after diverging from each other, may evolve under differential selective regimes, leading to contrasting patterns of structural diversity. [ABSTRACT FROM AUTHOR]

This study aimed to elucidate the bacteriological events occurring within the gut of Calliphora vicina, selected as the European representative of blow flies held responsible for the spread of anthrax during epidemics in certain parts of the world. Green-fluorescent-protein-carrying derivatives of Bacillus anthracis were used. These lacked either one of the virulence plasmids pXO1 and pXO2 and were infected, or not infected, with a worm intestine phage (Wip4) known to influence the phenotype and survival of the pathogen. Blood meals were prepared for the flies by inoculation of sheep blood with germinated and, in case of pXO2+ strains, encapsulated cells of the four B. anthracis strains. After being fed for 4 h an initial 10 flies were externally disinfected with peracetic acid to ensure subsequent quantitation representing ingested B. anthracis only. Following neutralization, they were crushed in sterile saline. Over each of the ensuing 7 to 10 days, 10 flies were removed and processed the same way. In the absence of Wip4, strains showed steady declines to undetectable in the total B. anthracis counts, within 7–9 days. With the phage infected strains, the falls in viable counts were significantly more rapid than in their uninfected counterparts. Spores were detectable in flies for longer periods than vegetative bacteria. In line with the findings in both biting and non-biting flies of early workers our results indicate that B. anthracis does not multiply in the guts of blow flies and survival is limited to a matter of days. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the usefulness of dynamic susceptibility contrast (DSC) enhanced perfusion MR imaging in predicting major genetic alterations in glioblastomas. Materials and Methods: Twenty-five patients (M:F = 13∶12, mean age: 52.1±15.2 years) with pathologically proven glioblastoma who underwent DSC MR imaging before surgery were included. On DSC MR imaging, the normalized relative tumor blood volume (nTBV) of the enhancing solid portion of each tumor was calculated by using dedicated software (Nordic TumorEX, NordicNeuroLab, Bergen, Norway) that enabled semi-automatic segmentation for each tumor. Five major glioblastoma genetic alterations (epidermal growth factor receptor (EGFR), phosphatase and tensin homologue (PTEN), Ki-67, O6-methylguanine-DNA methyltransferase (MGMT) and p53) were confirmed by immunohistochemistry and analyzed for correlation with the nTBV of each tumor. Statistical analysis was performed using the unpaired Student t test, ROC (receiver operating characteristic) curve analysis and Pearson correlation analysis. Results: The nTBVs of the MGMT methylation-negative group (mean 9.5±7.5) were significantly higher than those of the MGMT methylation-positive group (mean 5.4±1.8) (p = .046). In the analysis of EGFR expression-positive group, the nTBVs of the subgroup with loss of PTEN gene expression (mean: 10.3±8.1) were also significantly higher than those of the subgroup without loss of PTEN gene expression (mean: 5.6±2.3) (p = .046). Ki-67 labeling index indicated significant positive correlation with the nTBV of the tumor (p = .01). Conclusion: We found that glioblastomas with aggressive genetic alterations tended to have a high nTBV in the present study. Thus, we believe that DSC-enhanced perfusion MR imaging could be helpful in predicting genetic alterations that are crucial in predicting the prognosis of and selecting tailored treatment for glioblastoma patients. [ABSTRACT FROM AUTHOR]

The skin secretion of many amphibians contains an arsenal of bioactive molecules, including hormone-like peptides (HLPs) acting as defense toxins against predators, and antimicrobial peptides (AMPs) providing protection against infectious microorganisms. Several amphibian taxa seem to have independently acquired the genes to produce skin-secreted peptide arsenals, but it remains unknown how these originated from a non-defensive ancestral gene and evolved diverse defense functions against predators and pathogens. We conducted transcriptome, genome, peptidome and phylogenetic analyses to chart the full gene repertoire underlying the defense peptide arsenal of the frog Silurana tropicalis and reconstruct its evolutionary history. Our study uncovers a cluster of 13 transcriptionally active genes, together encoding up to 19 peptides, including diverse HLP homologues and AMPs. This gene cluster arose from a duplicated gastrointestinal hormone gene that attained a HLP-like defense function after major remodeling of its promoter region. Instead, new defense functions, including antimicrobial activity, arose by mutation of the precursor proteins, resulting in the proteolytic processing of secondary peptides alongside the original ones. Although gene duplication did not trigger functional innovation, it may have subsequently facilitated the convergent loss of the original function in multiple gene lineages (subfunctionalization), completing their transformation from HLP gene to AMP gene. The processing of multiple peptides from a single precursor entails a mechanism through which peptide-encoding genes may establish new functions without the need for gene duplication to avoid adaptive conflicts with older ones. [ABSTRACT FROM AUTHOR]

Host defence peptides (HDPs) are expressed throughout the animal and plant kingdoms. They have multifunctional roles in the defence against infectious agents of mammals, possessing both bactericidal and immune-modulatory activities. We have identified a novel family of molecules secreted by helminth parasites (helminth defence molecules; HDMs) that exhibit similar structural and biochemical characteristics to the HDPs. Here, we have analyzed the functional activities of four HDMs derived from Schistosoma mansoni and Fasciola hepatica and compared them to human, mouse, bovine and sheep HDPs. Unlike the mammalian HDPs the helminth-derived HDMs show no antimicrobial activity and are non-cytotoxic to mammalian cells (macrophages and red blood cells). However, both the mammalian- and helminth-derived peptides suppress the activation of macrophages by microbial stimuli and alter the response of B cells to cytokine stimulation. Therefore, we hypothesise that HDMs represent a novel family of HDPs that evolved to regulate the immune responses of their mammalian hosts by retaining potent immune modulatory properties without causing deleterious cytotoxic effects. [ABSTRACT FROM AUTHOR]

Antimicrobial peptides (AMPs) belong to a class of natural microbicidal molecules that have been receiving great attention for their lower propensity for inducing drug resistance, hence, their potential as alternative drugs to conventional antibiotics. By generating AMP libraries, one can study a large number of candidates for their activities simultaneously in a timely manner. Here, we describe a novel methodology where in silico designed AMP-encoding oligonucleotide libraries are cloned and expressed in a cellular host for rapid screening of active molecules. The combination of parallel oligonucleotide synthesis with microbial expression systems not only offers complete flexibility for sequence design but also allows for economical construction of very large peptide libraries. An application of this approach to discovery of novel AMPs has been demonstrated by constructing and screening a custom library of twelve thousand plantaricin-423 mutants in Escherichia coli. Analysis of selected clones by both Sanger-sequencing and 454 high-throughput sequencing produced a significant amount of data for positionally important residues of plantaricin-423 responsible for antimicrobial activity and, moreover, resulted in identification of many novel variants with enhanced specific activities against Listeria innocua. This approach allows for generation of fully tailored peptide collections in a very cost effective way and will have countless applications from discovery of novel AMPs to gaining fundamental understanding of their biological function and characteristics. [ABSTRACT FROM AUTHOR]

Anthrax is a zoonose caused by the organism Bacillus anthracis. Anthrax affects mainly animals, particularly cattle, but also humans. The economic loss caused by Anthrax in the Republic of Chad are very important. In this study, the potential role of tabanids in anthrax transmission has been evaluated. Tabanids were collected in infested areas of the Chari-Baguirmi Province in Chad and examined using standard bacteriological and biochemical methods. Hundreds of anthrax bacilli were isolated: in this, about 89% of the 1499 tabanids examined were contaminated by anthrax organisms. B anthracis spores were recovered from wings (31.9%) and legs (22.1%). Vegetative cells were recovered from mouthparts (18.8%) and midguts (16.3%). Anthrax Bacilli were also isolated from cattle and humans, including nine cutaneous cases associated with tabanids bites. All B. anthracis isolates displayed similar biological properties whatever their origin. They were non motile, sensitive to penicillin, non hemolytic and fully virulent as they can elicit the disease in experimental animals. All but one biochemical character were identical out of the 49 tested. Isolates were sensitive to meticillin, tetracycline, nitrofurantoin, piperacillin, oxytetracycline, sulphathiazol, benzathien-penicillin and chloramphenicol. Resistance was found against polymixin, fusidic acid, clindomycin and sisomycin. Given together, the results suggested that tabanids could be an important vector of Anthrax in Chad. [ABSTRACT FROM AUTHOR]

Examination of 3,960 goats brought from six districts of Jammu province and slaughtered at Jammu abattoir from July 2005 to June 2006 revealed 47.22% prevalence of larval stages of warble fly ( Przhevalskiana silenus Brauer, 1858) in goats. Highest prevalence was recorded in Udhampur (56.44%) and lowest in Doda district (13.49%). Classification of the study area into four zones based on height (meters above sea level), viz., zone I (300-325 m asl), zone II (325-800 m asl), zone III (800-1,500 m asl), and zone IV (>1,500 m asl), revealed significant ( p < 0.01) difference in infestation among animals of zone II (71.68%), zone III (40.12%), and zone IV (22.41%). However, animals of zone I did not reveal any infestation. Statistical analysis in relation to age showed significant ( p < 0.01) difference among different age groups, i.e., <1 year (2.81%), 1-3 years (51.17%), and >3 years (43.16%). Breed-wise analysis also showed significantly ( p < 0.01) higher infestation rate among Bakerwali (51.51%) goats as compared to Beetal (42.59%). But no significant difference was recorded among male (47.81%) and female (46.82%) animals. The overall mean larva count (L1, L2, and L3) was observed to be 14.72 ± 0.34, ranging from 4 to 72. It was significantly ( p < 0.05) higher in animals of zone II (22.20 ± 0.21) as compared to goats of zones III (14.21 ± 0.41) and IV (7.73 ± 0.90). Age-wise analysis of mean larva count also showed significant ( P < 0.05) difference between animals of 1-3 years (16.25 ± 0.37) and >3 years of age (13.18 ± 0.40). Mean larvae count in relation to sex and breed did not reveal any significant difference. First-instar larvae (L) were recorded from May to mid-September, second larval stage (L) from mid-September to mid-December, and third-stage larvae (L) from mid-December to February. However, No larvae were recorded from March to April, which is suggestive of pupation period in this region. Thus, it is concluded that adult fly is active in April to June. The results further confirmed that internal life cycle of P. silenus is subcutaneous and no migration of larvae occurs. This is the first report from India, based on slaughter house study on the prevalence and biology of goat warble fly infestation. It will help in devising suitable prophylactic and eradication program to check the economic losses rendered by adult fly. [ABSTRACT FROM AUTHOR]

Background: Radiation-induced tumors (RIT) are increasingly recognized as delayed complications of brain irradiation during childhood. However, the true incidence is not established, their biology is poorly understood, and few guidelines exist regarding the long-term follow-up of irradiated children. Methods: We studied retrospectively patients irradiated for brain tumor under 18 years and followed in our institution since 1970. RIT were defined as new masses, different from the original tumor, occurring after delay in irradiated areas, and not related to phacomatosis. Results: Among 552 irradiated patients, 42 (7.6%) developed one or more RIT, 26 months to 29 years after irradiation (mean 12.8 years). The cumulated incidence was 2.0% at 5 years and 8.9% at 10 years. Of the patients, 73.8% were adult at the time of diagnosis of RIT, and 75% were diagnosed within 18.1 years after irradiation. We identified 60 cavernomas, 26 meningiomas, 2 malignant gliomas, 1 meningosarcoma, and 6 thyroid tumors. Compared with meningiomas, cavernomas appeared earlier, in children irradiated at an older age, and with a male predominance. Although RIT were correlated with higher irradiation doses, 80.9% of these occurred at some distance from the maximum irradiation field. Twenty-five lesions were operated in 20 patients; three patients died because of progression of the RIT. Conclusion: A significant number of patients undergoing irradiation for brain tumor during childhood develop a RIT, often during adulthood. Our data suggest that radiation-induced cavernomas result from angiogenetic processes rather than true tumorigenesis. Protracted follow-up with MRI is warranted in children irradiated for brain tumor. [ABSTRACT FROM AUTHOR]

Cattle hypodermosis (warble fly infestation) is a notorious veterinary problem throughout the world. Larvae of Hypoderma species cause a subcutaneous myiasis of domesticated and wild ruminants. This disease is caused by, Hypoderma bovis, Hypoderma lineatum in cattle whereas, Hypoderma diana, Hypoderma actaeon, and Hypoderma tarandi, affect roe deer, red deer, and reindeer, respectively. Adults of the cattle grub are commonly known as heel flies, warble flies, bomb flies or gad flies. The biology of hypodermosis is complex because it passes through ecto- as well as endoparasitic stages in the life cycle. The parasitic stage of hypodermosis lasts about 1 year in domesticated as well as in the wild animals, while in the adult stage, a free-living fly lasts only for few days. The diagnosis of hypodermosis is of prime importance for planning treatment and the eradication program. Generally, there are two methods that are routinely used for diagnosis of hypodermosis, i.e., the direct clinical examination and immuno diagnosis by the use of pooled serum and/or milk sample. For the control of hypodermosis, different preparations are available and their use in most of the countries is limited to an individual level but never cover the whole cattle population of a country. Re-infestation in the herd occurs due to the untreated animals that remain the reservoir of the disease. The disease causes huge economic losses in animal production due to the effect of this disease on meat, milk, and the leather industry. It can also affect the general health status as well as the immune system of the body of the diseased animals. As regards the control measures of the disease, different methods have been efficiently practiced and consequently this disease is controlled at national level in many European countries. [ABSTRACT FROM AUTHOR]

Although infections with Cyclospora cayetanensis are prevalent worldwide, many aspects of this parasite's life cycle and transmission remain unknown. Humans are the only known hosts of this parasite. Existing information on its endogenous development has been derived from histological examination of only a few biopsy specimens. Its asexual and sexual stages occur in biliary-intestinal epithelium. In histological sections, its stages are less than 10 μm, making definitive identification difficult. Asexual (schizonts) and sexual (gamonts) are located in epithelial cells. Male microgamonts have two flagella; female macrogametes contain wall-forming bodies. Oocysts are excreted in feces unsporulated. Sporulation occurs in the environment, but there are many unanswered questions concerning dissemination and survival of C. cayetanensis oocysts. Biologically and phylogenetically, C. cayetanensis closely resembles Eimeria spp. that parastize chickens; among them, E. acervulina most closely resembles C. cayetanensis in size. Here, we review known and unknown aspects of its life cycle and transmission and discuss the appropriateness of surrogates best capable of hastening progress in understanding its biology and developing mitigating strategies. [ABSTRACT FROM AUTHOR]

The article discusses the biology and treatment of medulloblastoma, the most common malignant brain tumour in childhood. The standard therapeutic approach to medulloblastoma consists of complete surgical resection followed by post-operative radiotherapy. Advances in understanding medulloblastoma have necessitated a re-evaluation of prognostic factors. The European International Society of Paediatric Oncology (SIOP) group aims to develop new studies according to biological and clinical factors.

In this review, we discuss the molecular characteristics, development, evolution, and therapeutic perspectives for pediatric high-grade glioma (pHGG) arising in cerebral hemispheres. Recently, the understanding of biology of pHGG experienced a revolution with discoveries arising from genomic and epigenomic high-throughput profiling techniques. These findings led to identification of prevalent molecular alterations in pHGG and revealed a strong connection between epigenetic dysregulation and pHGG development. Although we are only beginning to unravel the molecular biology underlying pHGG, there is a desperate need to develop therapies that would improve the outcome of pHGG patients, as current therapies do not elicit significant improvement in median survival for this patient population. We explore the molecular and cell biology and clinical state-of-the-art of pediatric high-grade gliomas (pHGGs) arising in cerebral hemispheres. We discuss the role of driving mutations, with a special consideration of the role of epigenetic-disrupting mutations. We will also discuss the possibilities of targeting unique molecular vulnerabilities of hemispherical pHGG to design innovative tailored therapies. [ABSTRACT FROM AUTHOR]