Serum biomarkers for sepsis in children with febrile neutropenia and cancer.

The National Institute for Health and Care Excellence (NICE) defines febrile neutropenia or "neutropenic sepsis" as a patient with an absolute neutrophil count (ANC) less than 0.5 x 109/L and temperature >38°C or signs and symptoms of sepsis.

Molecular Typing of Bois Noir Phytoplasma Strains in the Chianti Classico Area (Tuscany, Central Italy) and Their Association with Symptom Severity in Vitis vinifera 'Sangiovese'.

Bois noir (BN) is the most widespread disease of the grapevine yellows complex in the Euro-Mediterranean area. BN is caused by 'Candidatus Phytoplasma solani' (BNp), transmitted from herbaceous plants to grapevine by polyphagous insect vectors. In this study, genetic diversity among BNp strains and their prevalence and possible association with grapevine symptom severity were investigated in a Sangiovese clone organic vineyard in the Chianti Classico area (Tuscany). Field surveys over 2 years revealed a range of symptom severity on grapevine and an increase of BN incidence. A TaqMan allelic discrimination assay detected only tufB type b among BNp strains, suggesting the prevalence of the bindweed-related ecology. Nucleotide sequence analyses of vmp1 and stamp genes identified 12 vmp1 and 16 stamp sequence variants, showing an overall positive selection for such genes. The prevalent genotype was Vm43/St10, reported for the first time in this study and closely related to strains identified only in the French Eastern Pyrenees. BNp strains identified in the examined vineyard and mostly grouped in separate bindweed-related phylogenetic clusters showed statistically significant differences in their distribution in grapevines exhibiting distinct symptom severity. These results suggest the possible occurrence of a range of virulence within BNp strain populations in the Chianti Classico area.

Influence of TNF-α inhibition on oxidative stress of rheumatoid arthritis patients.

The aim of this study was to assess circulating levels of reactive oxygen metabolites (ROMs) as a marker of oxidative stress in rheumatoid arthritis (RA) patients during an anti-tumor necrosis factor alpha (TNF-α) treatment. We enrolled 40 patients with RA (36 females; age 53 ± 13 yrs) treated with different subcutaneously administered TNF-α inhibitors. The oxidative status was determined on the basis of plasma samples taken before, at 24 and 52 weeks of the anti-TNF-α treatment. Hydroperoxide levels were measured using the d-ROMs test, a useful clinically proven oxidative stress marker. During the anti-TNF-α therapy, we observed a significant reduction in serum ROMs levels in RA patients from 33.2 ± 10 mg H2O2/L at baseline to 29.5 ± 7 and 29.3 ± 9 mg H2O2/L, at 24 and 52 weeks, respectively (p<0.05). We also identified a significant correlation between the oxidative stress status and the disease activity score on 28 joints/C-reactive protein and health assessment questionnaire disability index. The results of our study demonstrate that a good control of the disease with anti-TNF-α agents can reduce oxidative stress in RA patients. However, further studies of larger patient cohorts are needed to confirm these preliminary data.

First Report of the NA2 Lineage of Phytophthora ramorum from an Ornamental Rhododendron in the Interior of California.

In July 2012, we collected a rhododendron var. Trilby with twig dieback symptoms in the lower canopy, consistent with the disease "ramorum blight" caused by Phytophthora ramorum. The symptomatic plant had been planted a year earlier to replace a dead rhododendron in a landscape setting in Placer County, California (Lat: 39.036216°; Long: -120.999274°), Sierra Nevada foothills at ~600 m elevation. Isolations yielded a culture with a fast growth rate and overall morphology resembling the P. ramorum NA2 lineage described by Ivors et al. (4). DNA was extracted from the culture as described previously (4) and six SSR loci: MS18, MS39, MS43, MS45, MS64, MS145, were amplified (2,4). Allelic patterns were compared with those of three testers from each of the three lineages NA1, NA2, and EU1 known to be present in ornamental plants in North America, and they unambiguously confirmed the isolate belongs to the NA2 lineage of the pathogen. Although the symptomatic plant was confined to a landscape setting, it had been planted in that location for a year, providing a possible source of inoculum for the surrounding area. This is the first report of P. ramorum from the Sierra Nevada eco-region in the interior of California. It is also the first report of a NA2 isolate from a plant outside of commercial nurseries in California. The mating type of the isolate was not determined, but NA2 isolates are normally A2, the same mating type of NA1 isolates. The only other report of a NA2 isolate found outside of a nursery is from Washington State (1). Although there is no evidence the pathogen may have infected other plants, the infected rhododendron was found at a location situated over 100 km east of the closest known infestation (www.sodmap.org). Additionally, this is the first report of the pathogen outside the coast mountain range of California. Because the three lineages are genetically and phenotypically distinct (3), the escape of NA2 or EU1 isolates, both still absent from plants in natural settings, could have significant implications for California ecosystems. This finding highlights that introductions of P. ramorum via ornamental plants are still possible, in spite of current regulations. References: (1) G. Chastagner et al. Phytopathology 101:S32, 2011. (2) P. P. Croucher et al. Biol. Invasions 15:2281, 2013. (3) N. J. Grünwald et al. Trends Microbiol. 20:131, 2012. (4) K. Ivors et al. Mol. Ecol. 15:1493, 2006.

Household model of Chagas disease vectors (Hemiptera: Reduviidae) considering domestic, peridomestic, and sylvatic vector populations.

ABSTRACT Disease transmission is difficult to model because most vectors and hosts have different generation times. Chagas disease is such a situation, where insect vectors have 1-2 generations annually and mammalian hosts, including humans, can live for decades. The hemataphagous triatominae vectors (Hemiptera: Reduviidae) of the causative parasite Trypanosoma cruzi (Kinetoplastida: Trypanosomatidae) usually feed on sleeping hosts, making vector infestation of houses, peridomestic areas, and wild animal burrows a central factor in transmission. Because of difficulties with different generation times, we developed a model considering the dwelling as the unit of infection, changing the dynamics from an indirect to a direct transmission model. In some regions, vectors only infest houses; in others, they infest corrals; and in some regions, they also infest wild animal burrows. We examined the effect of sylvatic and peridomestic vector populations on household infestation rates. Both sylvatic and peridomestic vectors increase house infestation rates, sylvatic much more than peridomestic, as measured by the reproductive number R0. The efficacy of manipulating parameters in the model to control vector populations was examined. When R0 > 1, the number of infested houses increases. The presence of sylvatic vectors increases R0 by at least an order of magnitude. When there are no sylvatic vectors, spraying rate is the most influential parameter. Spraying rate is relatively unimportant when there are sylvatic vectors; in this case, community size, especially the ratio of houses to sylvatic burrows, is most important. The application of this modeling approach to other parasites and enhancements of the model are discussed.

First Report of Knot Disease Caused by Pseudomonas savastanoi on Sweet Olive in Central Italy.

In April 2012 the presence of hyperplastic outgrowths on trunks, branches, and twigs of sweet olive plants, Osmanthus fragrans Lour (Fam. Oleaceae), was recorded in two ornamental hedges made up of five and four plants, respectively, in the city center of Montecatini (Pistoia-Italy). All sweet olive plants were seriously affected by the disease with outgrowths appearing either singly or close together, often forming a single mass that could extend up to 20 cm along the stems, occasionally surrounding the entire circumference. The symptoms observed on O. fragrans closely resembled those induced by the bacterium Pseudomonas savastanoi on Olea europea (common olive) and other plant species. Suspecting a bacterial origin of the disorder, young knots were collected from four diseased plants and used for bacterial isolation with standard techniques on nutrient sucrose agar medium (1). After 3 days of incubation at 26°C, non-levan forming colonies about 3 mm in diameter that were circular, convex, smooth, and cream colored with entire margins appeared on the surface of the agar medium. Purified isolates were gram negative, levan negative, oxidase negative, potato rot negative, arginine dihydrolase negative, showed a tobacco hypersensitive reaction, and tested positive to PCR screening for the presence of the iaaM (tryptophan-2-monooxygenase), iaaH (indoleacetamide hydrolase), ptz (isopentenyl transferase) (1) and iaaL (IAA-lysine synthethase) (3) genes. Three isolates were selected arbitrarily and further characterized by sequencing a fragment of the housekeeping genes rpoD (sigma factor 70) and pgi (phosphoglucose isomerase) (2). All sequenced gene fragments, of 620 bp and 552 bp for the rpoD and pgi genes, respectively, were identical to those of P. savastanoi pv. savastanoi strain NCPPB3335. The pathogenicity of the three isolates was verified on three O. fragrans plants and three Olea europea (cv. Frantoio) plants. Per each isolate, three 1-cm wounds were made on the branches of each plant using a sterile scalpel dipped in a bacterial suspension (1 × 108 CFU/ml). P. savastanoi pv. savastanoi PVFi-t2b isolated from olive was also inoculated as reference strain. After 30 days, all isolates including the reference strain induced typical knots on both plant species while no symptoms were observed on wounds inoculated with sterile water. Bacteria were reisolated from induced knots and Koch's postulates were confirmed. On the basis of biochemical tests, PCR screening, pathogenicity testing, and sequence analyses, the causal agent of knot disease on O. fragrans was identified as P. savastanoi. The potential susceptibility of O. aquifolium Sieb. to the causal agent of olive knot disease has been demonstrated in the past by means of artificial inoculations but interestingly, in the same trials, O. fragrans had tested negative (4). To the best of our knowledge, this is the world's first report of O. fragrans as natural host of P. savastanoi, which extends the growing list of cultivated and ornamental plant species affected by this phytopathogenic bacterium. References: (1) G. Marchi et al. Eur J. Plant Pathol. 112:101, 2005. (2) N. Parkinson et al. Plant Pathol. 60:338, 2011. (3) R. Penyalver et al. Appl. Environ. Microbiol. 66:2673, 2000. (4) C. O. Smith. Phytopathology 12:271, 1922.

Occurrence of Lily mottle virus on Lilium in Italy.

Lily mottle virus (LMoV), a member of the genus Potyvirus, is one of the main viruses infecting lily. Symptoms on lily differ according to the susceptibility and sensitivity of different cultivars and hybrids. They range from leaf mottle or mosaic, vein clearing, chlorotic and yellow streaking, leaf curling, and necrotic spots, to milder forms of leaf symptoms. Plants may even be symptomless at some stages of growth. A varietal collection of Lilium from the early 1990s is held in Pistoia Province (Tuscany, Italy) and is composed of Asian hybrids obtained from intraspecific breeding of commercial cultivars. During a survey conducted from May to June 2010, several plants showing vein clearing, leaf mottle, leaf mosaic, and reddish brownish necrotic spots were observed. Leaf samples from 60 symptomatic or symptomless lily plants, belonging to 20 cultivars, were collected and tested for the presence of LMoV. Samples were assayed by double-antibody sandwich (DAS)-ELISA and eight of them, belonging to four different cultivars, tested positive. Total RNA was extracted from 2 g of leaf tissue of every collected sample according to the protocol described earlier (3) and cDNA synthesis was performed with an iScript cDNA Synthesis Kit (Bio-Rad, Hercules, CA). Samples were tested by reverse transcription (RT)-PCR and real-time PCR assays using primers LMoV1 (5'-GCAAATGAGACACTCAATGCTG-3') and LMoV2 (5'-CGTGCGTGAAGTAACTTCATAG-3') designed to amplify 651 bp of the coat protein (CP) gene of LMoV (1). Results obtained with RT-PCR and real-time PCR exactly matched those achieved with ELISA assay, and the eight positive samples showed amplicons of the expected size. PCR products from five infected samples were directly sequenced from both directions and submitted in GenBank (Accessions Nos. JQ655106 to JQ655110). Our isolates share more than 99% nucleotide identity among each other. Comparison with other LMoV-CP gene sequences present in GenBank showed nucleotide identities ranging from 93 to 94% with LMoV isolates from South Korea (GenBank Accession Nos. GQ150683 to GQ150686), China (GenBank Accession Nos. EU348826, AJ748256, AJ564636, and AJ564637), Australia (GenBank Accession No. JN127341), and Japan (GenBank Accession No. AB570195). To our knowledge, this is the first report of LMoV on Lilium in Italy where this virus was already reported to infect escarole (2). Considering the economic importance of Lilium production as a flowering plant in Pistoia Province, and in several other areas of Italy, the report of LMoV present on lilies suggests the use of healthy propagation material and the adoption of preventive measures to avoid its diffusion. References: (1) J.-H. Lim et al. Korean J. Microbiol. 45:251, 2009. (2) V. Lisa et al. Plant Dis. 86:329, 2002. (3) D. J. MacKenzie et al. Plant Dis. 81:222, 1997.

Anatomical and biochemical studies of Spartium junceum infected by Xylella fastidiosa subsp. multiplex ST 87.

Spartium junceum L. is a typical species of Mediterranean shrubland areas, also grown in gardens and parks as an ornamental. In recent years in Europe, S. junceum has been recurrently found to be infected by different subspecies and genotypes of the quarantine regulated bacterium Xylella fastidiosa (Xf). This work presents for the first time the anatomy of S. junceum plants that we found, by means of genetic and immunochemistry analysis, to be naturally infected by Xf subsp. multiplex ST87 (XfmST87) in Monte Argentario (Grosseto, Tuscany, Italy), a new outbreak area within the EU. Our anatomical observations showed that bacteria colonized exclusively the xylem conductive elements and moved horizontally to adjacent vessels through pits. Interestingly, a pink/violet matrix was observed with Toluidine blue staining in infected conduits indicating a high content of acidic polysaccharides. In particular, when this pink-staining matrix was observed, bacterial cells were either absent or degenerated, suggesting that the matrix was produced by the host plant as a defense response against bacterial spread. In addition, a blue-staining phenolic material was found in the vessels and, at high concentration, in the pits and inter-vessels. SEM micrographs confirmed that polysaccharide and phenolic components showed different structures, which appear to be related to two different morphologies: fibrillary and granular, respectively. Moreover, our LM observations revealed bacterial infection in xylem conductive elements of green shoots and leaves only, and not in those of other plant organs such as roots and flowers.

A large population of galaxies 9 to 12 billion years back in the history of the Universe.

To understand the evolution of galaxies, we need to know as accurately as possible how many galaxies were present in the Universe at different epochs. Galaxies in the young Universe have hitherto mainly been identified using their expected optical colours, but this leaves open the possibility that a significant population remains undetected because their colours are the result of a complex mix of stars, gas, dust or active galactic nuclei. Here we report the results of a flux-limited I-band survey of galaxies at look-back times of 9 to 12 billion years. We find 970 galaxies with spectroscopic redshifts between 1.4 and 5. This population is 1.6 to 6.2 times larger than previous estimates, with the difference increasing towards brighter magnitudes. Strong ultraviolet continua (in the rest frame of the galaxies) indicate vigorous star formation rates of more than 10-100 solar masses per year. As a consequence, the cosmic star formation rate representing the volume-averaged production of stars is higher than previously measured at redshifts of 3 to 4.

Massive venous thrombosis of inferior vena cava as primary manifestation of renal Ewing's sarcoma.

We report an extraordinarily rare case of a 17-year-old male with an extraskeletal Ewing's sarcoma (ESS) of the kidney and a massive thrombosis involving the inferior vena cava (IVC), from the iliac axis to the right atrium. This onset resembled renal cell carcinoma (RCC), although histological examination revealed it was an extraskeletal Ewing's sarcoma/peripheral neuro-ectodermal tumor (EES/PNET). EES/PNET should benefit from neoadjuvant chemotherapy to reduce the risk of metastasis and of recurrent disease due to delay in suitable treatment. Therefore, in the presence of a renal mass with tumor extension of IVC, it is reasonable to bear in mind that other tumors, apart from RCC, could occur. In such cases, a US or CT-scan guided biopsy could be useful.

Root Infections May Challenge Management of Invasive Phytophthora spp. in U.K. Woodlands.

Because sporulation of Phytophthora ramorum and P. kernoviae on Rhododendron ponticum, an invasive plant, serves as primary inoculum for trunk infections on trees, R. ponticum clearance from pathogen-infested woodlands is pivotal to inoculum management. The efficacy of clearance for long-term disease management is unknown, in part due to lack of knowledge of pathogen persistence in roots and emerging seedlings. The main objectives of this work were to (i) investigate whether both pathogens infect R. ponticum roots, (ii) determine the potential for residual inoculum of P. kernoviae to infect R. ponticum seedlings in cleared woodlands, and (iii) assess potential for R. ponticum roots to support survival and transmission of P. kernoviae. Roots of R. ponticum were collected from both unmanaged and cleared woodlands and assessed for pathogen recovery. Both P. ramorum and P. kernoviae were recovered from asymptomatic roots of R. ponticum in unmanaged woodlands, and P. kernoviae was recovered from asymptomatic roots from seedlings in cleared woodland. Oospore production of P. kernoviae was observed in naturally infected R. ponticum foliage and in inoculated roots. Roots also supported P. kernoviae sporangia production. The results of this study suggest that post-clearance management of R. ponticum regrowth is necessary for long-term inoculum management in invaded woodlands.

Development of Three Molecular Diagnostic Tools for the Identification of the False Codling Moth (Lepidoptera: Tortricidae).

Three molecular protocols using qPCR TaqMan probe, SYBR Green, and loop-mediated isothermal amplification (LAMP) methods were set up for the identification of larvae and adults of an African invasive moth, Thaumatotibia leucotreta (Meyrick, 1913) (Lepidoptera: Tortricidae). The DNA extracts from larval and adult samples of T. leucotreta were perfectly amplified with an average Ct value of 19.47 ± 2.63. All assays were demonstrated to be inclusive for T. leucotreta and exclusive for the nontarget species tested; the absence of false positives for nontarget species showed a 100% of diagnostic specificity and diagnostic sensitivity for all assays. With the SYBR Green protocol, the Cq values were only considered for values less than 22 (cutoff value) to prevent false-positive results caused by the late amplification of nonspecific amplicons. The limit of detection (LoD) for the qPCR probe protocol was equal to 0.02 pg/µl while a value equal to 0.128 pg/µl for the qPCR SYBR Green assay and LAMP method were established, respectively. The intrarun variabilities of reproducibility and repeatability in all the assays evaluated as CV%, ranged between 0.21 and 6.14, and between 0.33 and 9.52, respectively; the LAMP values were slightly higher than other assays, indicating a very low interrun variability. In order for an operator to choose the most desirable method, several parameters were considered and discussed. For future development of these assays, it is possible to hypothesize the setup of a diagnostic kit including all the three methods combined, to empower the test reliability and robustness.

Acute respiratory distress following fine needle aspiration of thyroid nodule: case report and review of the literature.

BACKGROUND: Fine needle aspiration (FNA) is a widely used practice to assess thyroid lesions, with a low morbidity rate. Although neck hematomas following this procedure are quite common, only three cases of massive hemorrhage causing acute airways obstruction have been previously described. CASE REPORT: We report the case of a 74 years old female with acute respiratory distress following ultrasound-guided FNA for a right paraisthmic thyroid nodule. The patient was admitted to the Emergency Room (ER) 6 hours after the procedure with a large neck hematoma compressing the cervical trachea and requiring surgical decompression. Patient underwent endotracheal intubation followed by isthmectomy and evacuation of the hematoma. Extubation was made 24 hours later in the Intensive Care Unit and the patient was discharged after 48 hours uneventfully. CONCLUSIONS: Acute thyroid hemorrhage following FNA is very rare but still possible. Prompt intervention is mandatory for patients with rapidly evolving symptoms.

Worldwide Network for Blood and Marrow Transplantation (WBMT) recommendations for establishing a hematopoietic stem cell transplantation program in countries with limited resources (Part II): Clinical, technical and socio-economic considerations.

The development of hematopoietic stem cell transplantation (HSCT) programs can face significant challenges in most developing countries because such endeavors must compete with other government health care priorities, including the delivery of basic services. While this is may be a limiting factor, these countries should prioritize development of the needed expertise to offer state of the art treatments including transplantation, by providing financial, technological, legal, ethical and other needed support. This would prove beneficial in providing successful programs customized to the needs of their population, and potentially provide long-term cost-savings by circumventing the need for their citizens to seek care abroad. Costs of establishing HSCT program and the costs of the HSCT procedure itself can be substantial barriers in developing countries. Additionally, socioeconomic factors intrinsic to specific countries can influence access to HSCT, patient eligibility for HSCT and timely utilization of HSCT center capabilities. This report describes recommendations from the Worldwide Network for Blood and Marrow Transplantation (WBMT) for establishing HSCT programs with a specific focus on developing countries, and identifies challenges and opportunities for providing this specialized procedure in the resource constrained setting.

Survival, dispersal, and potential soil-mediated suppression of Phytophthora ramorum in a California redwood-tanoak forest.

Because the role of soil inoculum of Phytophthora ramorum in the sudden oak death disease cycle is not well understood, this work addresses survival, chlamydospore production, pathogen suppression, and splash dispersal of the pathogen in infested forest soils. Colonized rhododendron and bay laurel leaf disks were placed in mesh sachets before transfer to the field in January 2005 and 2006. Sachets were placed under tanoak, bay laurel, and redwood at three vertical locations: leaf litter surface, litter-soil interface, and below the soil surface. Sachets were retrieved after 4, 8, 20, and 49 weeks. Pathogen survival was higher in rhododendron leaf tissue than in bay tissue, with >80% survival observed in rhododendron tissue after 49 weeks in the field. Chlamydospore production was determined by clearing infected tissue in KOH. Moist redwood-associated soils suppressed chlamydospore production. Rain events splashed inoculum as high as 30 cm from the soil surface, inciting aerial infection of bay laurel and tanoak. Leaf litter may provide an incomplete barrier to splash dispersal. This 2-year study illustrates annual P. ramorum survival in soil and the suppressive nature of redwood-associated soils to chlamydospore production. Infested soil may serve as primary inoculum for foliar infections by splash dispersal during rain events.

Phytophthora ramorum does not cause physiologically significant systemic injury to California bay laurel, its primary reservoir host.

California bay laurel trees (Umbellularia californica) play a crucial role in the reproduction and survival of Phytophthora ramorum in coastal California forests by supporting sporulation during the rainy season and by providing a means for the pathogen to survive the dry, Mediterranean summer. While bay laurel is thus critical to the epidemiology of sudden oak death and other P. ramorum diseases in California, the relatively minor symptoms observed on this reservoir host suggest that it may not sustain ecologically significant injury itself. The long-term role that P. ramorum will play in California forests will depend in part on the extent to which this pathogen decreases the ecological fitness of bay laurel. Despite the importance of this question, no study has yet investigated in detail the physiological impact that ramorum blight imposes on bay laurel. This experimental study quantifies the impact that P. ramorum has on artificially inoculated bay laurel seedlings with measurements that integrate the full injury that infection with an oomycete may cause: photosynthetic efficiency, total photosynthetic area, and growth. Leaf area and leaf mass were not impacted significantly by infection of P. ramorum. Photosynthetic efficiency was mildly depressed in symptomatic, but not asymptomatic leaves, despite unnaturally high levels of necrosis that were imposed on the seedlings. These results demonstrate that bay laurel trees suffer only minor injury from ramorum blight beyond visible necrotic symptoms. Consequently, it is highly likely that bay laurel will continue to be widely available as a host for P. ramorum in California forests, which has long-term implications for the composition of these forests.

Sources of inoculum for Phytophthora ramorum in a redwood forest.

ABSTRACT Sources of inoculum were investigated for dominant hosts of Phytophthora ramorum in a redwood forest. Infected trunks, twigs, and/or leaves of bay laurel (Umbellularia californica), tanoak (Lithocarpus densiflorus), and redwood (Sequoia sempervirens) were tested in the laboratory for sporangia production. Sporangia occurred on all plant tissues with the highest percentage on bay laurel leaves and tanoak twigs. To further compare these two species, field measurements of inoculum production and infection were conducted during the rainy seasons of 2003-04 and 2004-05. Inoculum levels in throughfall rainwater and from individual infections were significantly higher for bay laurel as opposed to tanoak for both seasons. Both measurements of inoculum production from bay laurel were significantly greater during 2004-05 when rainfall extended longer into the spring, while inoculum quantities for tanoak were not significantly different between the 2 years. Tanoak twigs were more likely to be infected than bay laurel leaves in 2003-04, and equally likely to be infected in 2004-05. These results indicate that the majority of P. ramorum inoculum in redwood forest is produced from infections on bay laurel leaves. Years with extended rains pose an elevated risk for tanoak because inoculum levels are higher and infectious periods continue into late spring.

Steam Sterilization of Equine Bone Block: Morphological and Collagen Analysis.

INTRODUCTION: The use of equine bone blocks is widely reported for bone augmentation techniques. The block must be shaped according to the form of the defect that should be regenerated. The shaping could be performed by hand before or during the surgery, in a sterile ambient, or using a CNC milling machine that could not be sterile. The aim of our study was to evaluate if a steam sterilization could provide a medical grade sterilization of the blocks and to evaluate if bone microstructure and collagen structures change after different steam sterilization protocols provided by mainstream autoclave. MATERIALS AND METHOD: Two blocks of equine bone were divided into 16 samples. 1 sample was used as control and not submitted to any treatment. 15 samples were infected with a Streptococcus faecalis bacterial culture. The samples were singularly packed, randomly divided into 3 groups, and submitted to autoclave sterilization on the same device. The groups were submitted to a sterilization cycle (Gr. A: 121°C, 1,16 bar for 20'; Gr. B:134°C, 2,16 bar for 4'; Gr. C: 134°C, 2,16 bar for 3.30 min.). 2 samples for each group were evaluated for the sterility. 3 samples for each group were observed at SEM to notice the macro- and microstructure modification and to confocal microscope to observe the collagen. RESULTS: All samples were sterile. The SEM evaluation showed, in all groups, a preserved morphological structure. Confocal microscope evaluation shows that the collagen structure appears to be more uniform and preserved in group C. CONCLUSION: Data show that autoclave steam sterilization could be reliable to obtain sterilization of equine bone blocks.