An 8-cm fiber is attached to a micromanipulator and ∼ 5 mm of the

An 8-cm fiber is attached to a micromanipulator and ∼ 5 mm of the end is inserted into the acid for 15- to 30-min periods, until the desired 5–20 μm diameter is achieved (Fig. 1A). After rinsing in distilled water, the tip of the tapered end is cut with a diamond knife to provide a sharp clean edge while the non-etched end of the fiber is glued into a connector (LC type, Thorlabs no. 86024-5500) and polished following standard

procedures (as described in ‘Fiber polishing notes’, Thorlabs no. FN96A). The next step is to place the optical fiber on the shank of the silicon probe. This procedure is carried out with the help of micromanipulators and under microscopic vision. The silicon probe is placed horizontally and the fiber is positioned with a slight angle (15–20°) with the etched tip touching the shank at the desired distance Epacadostat from the recording sites. Then the remaining part of the fiber is pushed high throughput screening down with a piece of metal microtube so that it lies parallel to the surface of the shank (Fig. 1B). Once the fiber is in place, ultraviolet (UV) light-curable glue (Thorlabs no. NOA61) is applied by hand to the fiber and shank using a single bristle of a cotton swab. After successful application, UV light (Thorlabs no. CS410) is applied for 5 min. This procedure can be done in multiple steps by repeating

the process of pushing and gluing the fiber gradually upwards along the shank. Finally, the non-etched portion of the fiber is glued to the bonding area of the probe to provide secure connection. To avoid breakage of the fiber during handling and implantation, the connector end of the fiber and the probe base are interconnected with a metallic bar or/and dental cement (Fig. 2A). We made different designs of integrated fiber-based optoelectronic silicon devices to address different sets of questions (Fig. 2). Either one or four shanks were equipped with optical fibers, and the distance between the fiber tip and the recording

sites varied from 100 to 300 μm, depending on the desired volume of stimulated tissue. For experiments requiring the stimulation of neurons located below the recording sites only, an extra optical fiber was glued at the back of the shanks and protruded 100 μm below the shank tip (Fig. 2C). To maintain minimal shank thickness (15 μm) and guide the placement of the optical fibers, long 12-μm-deep grooves were etched at the back of the shanks Glycogen branching enzyme using a solid-state YAG laser-based laser micromachining system (LaserMill; New Wave Research, Inc., Freemont, CA, USA). Following the laser cut, the silicon grooves were fine polished at the very end of the shanks by chemically assisted focused gallium ion beam milling using a dual beam Focus ion beam/scanning electron microscope workstation (FEI no. DB-820). Liquid metal ion source-based gallium beam (30 kV acceleration) current of 150 pA at the sample surface was assisted by xenon difluoride (XeF2) gas for chemically enhanced silicon etching of the shank substrate.

An 8-cm fiber is attached to a micromanipulator and ∼ 5 mm of the

An 8-cm fiber is attached to a micromanipulator and ∼ 5 mm of the end is inserted into the acid for 15- to 30-min periods, until the desired 5–20 μm diameter is achieved (Fig. 1A). After rinsing in distilled water, the tip of the tapered end is cut with a diamond knife to provide a sharp clean edge while the non-etched end of the fiber is glued into a connector (LC type, Thorlabs no. 86024-5500) and polished following standard

procedures (as described in ‘Fiber polishing notes’, Thorlabs no. FN96A). The next step is to place the optical fiber on the shank of the silicon probe. This procedure is carried out with the help of micromanipulators and under microscopic vision. The silicon probe is placed horizontally and the fiber is positioned with a slight angle (15–20°) with the etched tip touching the shank at the desired distance Selleck Pictilisib from the recording sites. Then the remaining part of the fiber is pushed TGF-beta inhibitor down with a piece of metal microtube so that it lies parallel to the surface of the shank (Fig. 1B). Once the fiber is in place, ultraviolet (UV) light-curable glue (Thorlabs no. NOA61) is applied by hand to the fiber and shank using a single bristle of a cotton swab. After successful application, UV light (Thorlabs no. CS410) is applied for 5 min. This procedure can be done in multiple steps by repeating

the process of pushing and gluing the fiber gradually upwards along the shank. Finally, the non-etched portion of the fiber is glued to the bonding area of the probe to provide secure connection. To avoid breakage of the fiber during handling and implantation, the connector end of the fiber and the probe base are interconnected with a metallic bar or/and dental cement (Fig. 2A). We made different designs of integrated fiber-based optoelectronic silicon devices to address different sets of questions (Fig. 2). Either one or four shanks were equipped with optical fibers, and the distance between the fiber tip and the recording

sites varied from 100 to 300 μm, depending on the desired volume of stimulated tissue. For experiments requiring the stimulation of neurons located below the recording sites only, an extra optical fiber was glued at the back of the shanks and protruded 100 μm below the shank tip (Fig. 2C). To maintain minimal shank thickness (15 μm) and guide the placement of the optical fibers, long 12-μm-deep grooves were etched at the back of the shanks Cetuximab in vitro using a solid-state YAG laser-based laser micromachining system (LaserMill; New Wave Research, Inc., Freemont, CA, USA). Following the laser cut, the silicon grooves were fine polished at the very end of the shanks by chemically assisted focused gallium ion beam milling using a dual beam Focus ion beam/scanning electron microscope workstation (FEI no. DB-820). Liquid metal ion source-based gallium beam (30 kV acceleration) current of 150 pA at the sample surface was assisted by xenon difluoride (XeF2) gas for chemically enhanced silicon etching of the shank substrate.

S-bound conveyance (aircraft, ship, or vehicle), or (2) within 7

S.-bound conveyance (aircraft, ship, or vehicle), or (2) within 72 hours after arriving in the United States, or (3) at any time after arriving in the United States from an illness possibly acquired during

international travel. We extracted the following data from QARS reports: demographics (age and sex), mode of transportation (aircraft, ship, land vehicle, or pedestrian), location of death, travel dates, traveler type (ie, passenger or crew member), citizenship, presence of chronic medical conditions, and cause of death. When data were missing from QARS death reports, we www.selleckchem.com/products/E7080.html contacted CDC quarantine stations, medical examiners’ offices, and hospitals to complete case reports. Data were entered into a Microsoft Excel® database. Causes of death were categorized as cancer, cardiovascular, infectious disease, unintentional injury, intentional injury, and other (Table 1). Death rates for passengers on international

commercial conveyances were calculated for each year, by conveyance type. To present full, continuous yearly data (ie, four quarters) and to adjust for seasonality, we defined year 1 as July 1, 2005 to June 30, 2006; year 2 as July 1, 2006 to June 30, 2007; and year 3 as July 1, 2007 Selleckchem MI-503 to June 30, 2008. We defined quarter 1 as January to March, quarter 2 as April to June, quarter 3 as July to September, and quarter 4 as October to December. To calculate mortality rates for cruise ship passengers, we divided the total number of reported cruise ship passenger deaths that met the case definition by the number of cruise passenger-nights traveled. We calculated the denominator by using data from the from U.S. Maritime Administration (MARAD) for cruises with an international itinerary and a port of arrival in the United States during years 1, 2, and 3.30 To determine

mortality rates for commercial aircraft passengers, we divided the total number of reported commercial aircraft passenger deaths that met the case definition by the number of airline passengers arriving in the United States from foreign ports. Denominator data were obtained from the U.S. Bureau of Transportation Statistics (BTS).31 Since MARAD and BTS do not collect data for crew members from cruise lines or airlines, respectively, we were unable to calculate crew mortality rates. We conducted bivariate analysis by using likelihood ratio chi-square tests, both asymptotic and exact, to evaluate associations between sex and cause of death. We analyzed monthly, quarterly, and yearly death rates among commercial aircraft and cruise ship passengers from July 2005 through June 2008 by using a general linear regression model in SAS (SAS 9.2, SAS Institute, Inc., Cary, NC, USA) to assess seasonality and trends in death rates over time.

We refer to this latter form of impulse as an ‘urge’ It relates

We refer to this latter form of impulse as an ‘urge’. It relates to how much someone wants something, driven by its perceived value. Urges constitute an important part of human behavior, both in healthy everyday life and in psychiatric disorders. Yet there is a paucity of methods to objectively index urges in terms of strength, timing (dynamics) and control. While it is possible

to measure the strength of the urge in terms of response time, or number of items chosen/consumed, or subjective self-report (Raylu & Oei, 2004; Seibt et al., 2007; Wulfert et al., 2009), these behavioral measures do not provide information about the dynamic unfolding of the urge in real-time, nor are they suitable for measuring urge control. If an urge is stopped then there is nothing to observe behaviorally. We

aimed to develop a technique to measure urges by assuming they would ‘spill over’ into learn more the motor system. This assumption has a precedent. For example, it has been shown that action is more vigorous for stimuli with higher motivational value, and that this has its counterpart in increased blood oxygen level-dependent (BOLD) activation in the nucleus accumbens area (Talmi et al., 2008). A different study used functional magnetic resonance imaging (fMRI) and skin conductance to show that Venetoclax ic50 value modulates behavioral activation and BOLD signal in the pallidum even with subliminal stimuli (Pessiglione et al., 2007). Yet a limitation of these studies is

that the subject knows exactly which response to make, so the increased activation may also reflect motor execution rather than a purer measure of motivation to respond. Nor do these measures provide the sub-second resolution needed to separate the effects of motivation from those of execution. A different approach used transcranial magnetic stimulation (TMS) of the primary motor cortex to show that motor excitability (recorded from the hand) was modulated by an upcoming potential reward (Kapogiannis et al., 2008). However, that study required passive viewing without any action and, moreover, varied both reward value and Etomidate the probability of getting reward, thus making it unclear whether the increased motor excitability relates to urge per se rather than any of arousal, expectancy or uncertainty. We developed a novel approach to index urges in the motor system using TMS and concurrent electromyography. In Experiment 1 we used a realistic and previously validated food paradigm with hungry human participants (Hare et al., 2009). In Experiment 2 we used a similar paradigm with monetary rewards. We hypothesized that stimuli associated with stronger urges (for food or money) would lead to higher motor excitability. We aimed to show that this would be manifest even before the subject knew which motor response to make. We also aimed to clarify the within-trial timing of the effect and also to address whether the effect depends on making an action.

We refer to this latter form of impulse as an ‘urge’ It relates

We refer to this latter form of impulse as an ‘urge’. It relates to how much someone wants something, driven by its perceived value. Urges constitute an important part of human behavior, both in healthy everyday life and in psychiatric disorders. Yet there is a paucity of methods to objectively index urges in terms of strength, timing (dynamics) and control. While it is possible

to measure the strength of the urge in terms of response time, or number of items chosen/consumed, or subjective self-report (Raylu & Oei, 2004; Seibt et al., 2007; Wulfert et al., 2009), these behavioral measures do not provide information about the dynamic unfolding of the urge in real-time, nor are they suitable for measuring urge control. If an urge is stopped then there is nothing to observe behaviorally. We

aimed to develop a technique to measure urges by assuming they would ‘spill over’ into find more the motor system. This assumption has a precedent. For example, it has been shown that action is more vigorous for stimuli with higher motivational value, and that this has its counterpart in increased blood oxygen level-dependent (BOLD) activation in the nucleus accumbens area (Talmi et al., 2008). A different study used functional magnetic resonance imaging (fMRI) and skin conductance to show that Y27632 value modulates behavioral activation and BOLD signal in the pallidum even with subliminal stimuli (Pessiglione et al., 2007). Yet a limitation of these studies is

that the subject knows exactly which response to make, so the increased activation may also reflect motor execution rather than a purer measure of motivation to respond. Nor do these measures provide the sub-second resolution needed to separate the effects of motivation from those of execution. A different approach used transcranial magnetic stimulation (TMS) of the primary motor cortex to show that motor excitability (recorded from the hand) was modulated by an upcoming potential reward (Kapogiannis et al., 2008). However, that study required passive viewing without any action and, moreover, varied both reward value and Selleck Pazopanib the probability of getting reward, thus making it unclear whether the increased motor excitability relates to urge per se rather than any of arousal, expectancy or uncertainty. We developed a novel approach to index urges in the motor system using TMS and concurrent electromyography. In Experiment 1 we used a realistic and previously validated food paradigm with hungry human participants (Hare et al., 2009). In Experiment 2 we used a similar paradigm with monetary rewards. We hypothesized that stimuli associated with stronger urges (for food or money) would lead to higher motor excitability. We aimed to show that this would be manifest even before the subject knew which motor response to make. We also aimed to clarify the within-trial timing of the effect and also to address whether the effect depends on making an action.

This study aimed to investigate the influence of patients’ percep

This study aimed to investigate the influence of patients’ perceptions and illness severity at the start on antidepressant-medication-taking behaviour. Methods  Eighteen community pharmacies in the Netherlands participated in this 6-month follow-up study. One hundred and ten patients presenting a first antidepressant prescription, prescribed by a general practitioner (GP), were included. A questionnaire was completed at inclusion, after 6 and 26 weeks. Key findings  Of all 110 patients, eight (7.3%) did not initiate drug taking, 32 (29.1%) discontinued use, six (5.5%) switched to different antidepressant medication, and 64 (58.2%) continued on the same antidepressant during follow-up. Compared to continuers,

non-initiators had lower belief scores for impact DAPT mw of illness (P = 0.044), perceived norm GP (P < 0.001), intention to take find protocol medication (P < 0.001), and attitude towards medication (P = 0.004). Furthermore, non-initiators were less severely depressed (P = 0.024). Discontinuers and continuers did not differ in illness severity at inclusion. However, discontinuers more often reported a non-specific reason for use, such as fatigue and sleeping problems (P = 0.014). Compared to continuers, switchers had higher illness severity scores at inclusion (depression, P = 0.041; anxiety, P = 0.050). During follow-up depression and anxiety severity improved for all treatment groups and

reached the same level of severity at 6 months. Conclusions  Patients’ illness and treatment perceptions and illness severity influence their decisions about antidepressant drug taking. Patients’ care could be improved by eliciting Methamphetamine patients’ beliefs about illness and treatment and assessing illness severity before prescribing. “
“Objective The aim was to evaluate the potential causes of dispensing-label errors at a hospital. Methods The study took place at a 1200-bed NHS Foundation Trust with two main pharmacy dispensaries (one manual and one automated). Face-to-face interviews were conducted with staff involved

in label-generation errors to obtain in-depth understanding of dispensing-label errors. Interviews were tape-recorded, transcribed and analysed with the aid of Nvivo into themes. Key findings Factors suggested as causing label-generation errors were illegible handwriting, lack of knowledge, hurrying through tasks, distractions, interruptions and the use of past medical records in generating labels. Self-checking every stage of the labelling process was suggested as the key to detecting and preventing errors. Conclusions The study highlights the vulnerability of the label-generation process to errors, with potential causes linked to organisational, environmental, task, team and individual factors. “
“Objective  Antihypertensive medications are important in the prevention of serious consequences of hypertension, such as stroke and heart failure.

Cultures were then diluted 1 : 100 with LB broth containing 10%

Cultures were then diluted 1 : 100 with LB broth containing 1.0% NaCl with or without 5 mM CaCl2 and grown with shaking at 37 °C for 3 h. After incubation, bacterial cultures were centrifuged and the bacterial pellets were solubilized with SDS sample buffer [50 mM Tris (pH 6.8), 2% SDS, 0.6% 2-mercaptoethanol, 10% glycerol,

1% bromophenol blue]. Secreted proteins were harvested by precipitation with cold trichloroacetic acid to a final concentration of 10% v/v on ice for 1 h, ABT-263 clinical trial followed by centrifugation at 48 000 g for 1 h. The pellets were rinsed in cold acetone and then solubilized in the SDS sample buffer. Samples for Western blot analysis were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The transferred membrane was blocked with 5% skimmed milk in Tris-buffered saline [20 mM Tris, 137 mM NaCl (pH 7.6)] containing 0.05% Tween 20 and probed with anti-VscC1, anti-VopD1 (Park et al., 2004), anti-VepA (VP1680) (Akeda et al., 2009), anti-ExsE and anti-TDH polyclonal antibodies diluted 1 : 10 000 in Can Get Signal Solution 1 (Toyobo) (Hiyoshi et al., 2010) and were then probed with horseradish peroxidase-conjugated goat anti-rabbit antibody (Zymed) diluted 1 : 10 000 in Can Get Signal Solution 2 (Toyobo). The blots were developed using an ECL Western blotting kit (Amersham). Vibrio parahaemolyticus strains harboring

a reporter plasmid containing the V. parahaemolyticus exsA promoter region (from −620 to +150 bp) were grown for 1 h at 37 °C in LB broth containing 1.0% NaCl. β-Galactosidase activity was assayed in Omipalisib cost cell lysates by the method of Miller (1972) using o-nitrophenyl-β-d-galactopyranoside as a substrate. As mentioned above,

there were no predicted CDS in the V. parahaemolyticus genome that corresponded to P. aeruginosa exsE. However, Farnesyltransferase we observed that a hypothetical CDS (VP1702) was encoded at the terminus region of the T3SS1 gene cluster, which contains several CDSs homologous to P. aeruginosa ExsA, ExsD and ExsC proteins (Fig. 1a). Therefore, we first constructed gene deletion mutant strains Δvp1701 (ΔexsC) and Δvp1702 in addition to ΔexsA (Δvp1699) and ΔexsD (Δvp1698) and determined the effect of gene deletion on the production of the T3SS1-related proteins (VscC1; an outer-membrane component of the type III protein secretion machinery and VepA; a T3SS1-specific effector protein involved in T3SS1-dependent cytotoxicity) (Akeda et al., 2009; Kodama et al., 2010). As reported previously, deletion of exsA (vp1699) reduced the level of VscC1 in bacterial pellets and the level of VepA in both bacterial pellets and the supernatant, whereas production of these proteins was clearly induced in the exsD (vp1698) mutant (Fig. 1b). As expected, the Δvp1701 mutant did not produce VscC1 or VepA.

The peak amplitude of RON was larger to voice as compared to musi

The peak amplitude of RON was larger to voice as compared to music deviants over BVD-523 supplier midline (F1,34 = 8.78, P < 0.01, ηp2 = 0.205) and mid-lateral (F1,34 = 7.508,

P = 0.01, ηp2 = 0.181) sites, with a trend in the same direction over lateral sites (F1,34 = 3.102, P = 0.087, ηp2 = 0.084), pointing to a greater ease at overcoming distraction when deviants were vocal as compared with musical in nature. Lastly, the mean amplitude of RON was significantly larger over the right as compared with the left hemisphere in lateral sites (F1,34 = 21.238, P < 0.01, ηp2 = 0.384), with a trend in the same direction in mid-lateral sites (F1,34 = 3.683, P = 0.063, ηp2 = 0.098). To determine whether an enhanced N1 is correlated with behavioral measures Sorafenib chemical structure of musical expertise, we examined a connection between the N1 peak amplitude and the following measures: onset of musical training, years of musical training, MAP scores, self-rated musical proficiency and the number of hours listening to music per week. The N1 peak amplitude averages were calculated for midline, mid-lateral and lateral sites for

each participant. Separate regression analyses were performed between each of the above behavioral measures and the N1 average for each scalp area. Because the amplitude of N1 was significantly smaller in response to standards compared with deviants [probably due to the refractoriness of the neurons responding to repeating standard sounds (Näätänen & Picton, 1987)], we conducted separate regression analyses on N1 to standards and on N1 to deviants. All reported P values are two-tailed. In the NAT condition, individuals with higher self-rated musical proficiency had a significantly larger N1 peak amplitude to both music and voice deviants over the mid-lateral (music deviants, r = 0.371, Lonafarnib in vivo P = 0.026; voice deviants, r = 0.338, P = 0.044) and midline (music deviants, r = 0.351, P = 0.036; voice deviants, r = 0.342, P = 0.041) sites, with a trend in the same direction over the lateral sites (music deviants, r = 0.315, P = 0.061; voice deviants, r = 0.281, P = 0.097).

Additionally, the N1 elicited by music deviants was larger over the lateral sites (r = 0.357, P = 0.032) in individuals with higher MAP scores. A relationship between the N1 peak amplitude to voice deviants and MAP scores showed a similar trend (r = 0.291, P = 0.085). None of the results in the ROT condition reached significance. In the NAT condition, individuals with higher self-rated musical proficiency had a significantly larger N1 peak amplitude to both music and voice standards over the midline (music standards, r = 0.335, P = 0.046; voice standards, r = 0.402, P = 0.015) and mid-lateral (music standards, r = 0.331, P = 0.049; voice standards r = 0.385, P = 0.02) sites. Individuals with higher MAP scores had a larger N1 to voice standards (r = 0.342, P = 0.041) and a marginally larger N1 to music standards (r = 0.295, P = 0.081) over the lateral sites.

On arrival, they still complained of itching, episodes of cough,

On arrival, they still complained of itching, episodes of cough, and weakness. P.F. also showed transient urticaria. Eosinophilia was still present (absolute count 8,270 mm−3, 55% for S.F. and 8,700 mm−3, 60% for P.F.). Rhabditoid larvae of S stercoralis were found in one of five stool samples provided find protocol by S.F. but in none of the five samples provided by P.F. (using

Ritchie’s fecal enrichment technique). Serology (an in-house IFAT for S stercoralis, with 97.4% sensitivity and 97.9% specificity),6 was positive, at minimum titer (ie, 1/20), only for S.F., whereas P.F. had a negative result. Fecal culture for S stercoralis resulted positive for both. Patients were treated with ivermectin, 200 µg/kg/d for 2 days, repeated after 1 month. All clinical signs disappeared. After 6 months, both patients were asymptomatic, with normal eosinophil count. Serology was found positive at minimum titer (1/20 ) in both patients 1 month after discharge and resulted

negative 3 and 6 months after treatment. We describe here the clinical and biological characteristics of acute strongyloidiasis, in a couple of travelers. This early invasive phase of human strongyloidiasis has never been reported in clinical settings, to our knowledge. Our two patients give the opportunity to more precisely describe this phase of the disease. Strongyloidiasis was probably acquired in Thailand Selleck ICG-001 where the disease prevalence, depending on the diagnostic technique and population under study, ranges from 2.3 to 19.2% (respectively in schoolchildren from West-Central Thailand and Thai workers who pursue overseas employment).7,8 Patients did not visit any other disease-endemic country before. We identified Koh Samui Island as the most likely site of infection. Indeed no bare skin exposure to humid soil was reported by the patients in Apulia where they came Gemcitabine concentration from or during travel in Malaysia, Singapore, and Bangkok where the patients always wore shoes. In contrast, during the last 4 days spent in the tourist resort in Koh Samui Island, they reported walking barefoot on the

grass around the bungalow. As Koh Samui is a very important touristic place, we may assume that other exposed travelers could have similarly acquired strongyloidiasis, an infection which goes largely under-reported. Little is known about the clinical manifestations of acute strongyloidiasis. Freedman gives a description of experimental infections in humans.9 Interestingly, he noticed a transient skin reaction at the site of larval entry that appears almost immediately after exposure to the larvae and lasted 1 to 21 days depending on the study. Within 10 days after exposure, a larval migration syndrome or Loeffler’s-like syndrome with pulmonary symptoms (cough, tracheal irritation, and asthma) and skin signs (acute urticaria and itching) may occur.

4% similarity of the clam isolates, which was higher than that ob

4% similarity of the clam isolates, which was higher than that observed between the fish isolate and either clam strain (98.2%). The topology of the maximum parsimony tree, obtained from 2D-PAGE analysis, and the phylogenetic tree, constructed with the maximum likelihood algorithm from concatenated sequences of 16S rRNA gene and five housekeeping genes (atpA, pyrH, recA, rpoA and rpoD), was very similar, confirming the closer relationship check details between the two clam isolates. Vibrio species are extensively

distributed in marine environments, associated with a wide range of marine organisms; some of the species are pathogenic to humans (Thompson et al., 2006; Beaz-Hidalgo et al., 2010). Genotyping strategies such as restriction fragment length polymorphism and pulse field gel electrophoresis have been used traditionally for epidemiological analysis of Vibrio isolates (Castro et al., 1997; Romalde et al., 2002). PCR typing methods have also been widely used, including randomly amplified polymorphic DNA analysis and repetitive-sequence-based polymerase chain reaction based on polymorphic, repetitive extragenic palindromic sequences and enterobacterial repetitive

intergenic consensus (Rodríguez et al., 2006). More recently, amplified fragment length polymorphism and multilocus sequence analysis (MLSA) (Maiden, 2006) have allowed a more precise identification of Vibrio species (Beaz-Hidalgo et al., 2008, 2010; and references therein). Proteomics could complement and extend PR-171 ic50 the nucleic acid analytical AG-014699 supplier technologies,

being an experimental link between the expressed product and the genome (Lester & Hubbard, 2002; Phillips & Bogyo, 2005; Norbeck et al., 2006; Cash, 2009; Zhang et al., 2010). 2D-PAGE has been successfully applied for the discrimination of closely related isolates (Cash et al., 1995; Dumas et al., 2008), revealing even more variability than with DNA–DNA hybridization, as protein content reflects dynamic changes produced in the cells as a response to changes in the environment (Andersen et al., 1984; Cash, 2009; Zhang et al., 2010). Vibrio tapetis is the causative agent of an epizootic infection in adult clams called brown ring disease (Borrego et al., 1996). The first studies indicated that strains of this pathogen constituted a homogeneous group. However, as new strains were isolated from different hosts, including different mollusk and fish species, some variability on the basis of their antigenic, phenotypic and genotypic characteristics has been demonstrated, leading to the description of three main groups within this species that correlate with the type of host (Castro et al., 1996, 1997; Romalde et al., 2002; Rodríguez et al., 2006). In this work, a proteomic method, 2D-PAGE, was used to study the intraspecific variability of representative strains of the three groups described for V. tapetis, as well as an additional indication of their phylogenetic relationship.