SynGenes: a Python class for standardizing nomenclatures of mitochondrial and chloroplast genes and a web form for enhancing searches for evolutionary analyses

BACKGROUND

The reconstruction of the evolutionary history of organisms has been greatly influenced by the advent of molecular techniques, leading to a significant increase in studies utilizing genomic data from different species. However, the lack of standardization in gene nomenclature poses a challenge in database searches and evolutionary analyses, impacting the accuracy of results obtained.

RESULTS

To address this issue, a Python class for standardizing gene nomenclatures, SynGenes, has been developed. It automatically recognizes and converts different nomenclature variations into a standardized form, facilitating comprehensive and accurate searches. Additionally, SynGenes offers a web form for individual searches using different names associated with the same gene. The SynGenes database contains a total of 545 gene name variations for mitochondrial and 2485 for chloroplasts genes, providing a valuable resource for researchers.

CONCLUSIONS

The SynGenes platform offers a solution for standardizing gene nomenclatures of mitochondrial and chloroplast genes and providing a standardized search solution for specific markers in GenBank. Evaluation of SynGenes effectiveness through research conducted on GenBank and PubMedCentral demonstrated its ability to yield a greater number of outcomes compared to conventional searches, ensuring more comprehensive and accurate results. This tool is crucial for accurate database searches, and consequently, evolutionary analyses, addressing the challenges posed by non-standardized gene nomenclature.

Evaluation of the Impact of Exposure To Heat and to By-Products of Combustion on the Health of Firefighters

Firefighters are often exposed to high temperatures and by-products of combustion, which can affect their health. In this study, we assessed the impact of acute exposure of firefighters in fire simulators. Twenty male firefighters were exposed to fire simulators, and observed in four phases: pre-exposure (group 0, control) and after the end of the first (group 1), second (group 2), and fourth (group 3) weeks of training. Blood samples were collected and dosed to evaluate the response of the immune, inflammatory (C-reactive protein, IL6, and IL10), and endocrine systems (cortisone, total testosterone, free testosterone, SHBG, bioavailable testosterone, TSH, and free T4). In groups 0, 1, and 3, a thermographic evaluation was also carried out to study the temperature and body heat flow of the participants. Regarding the inflammatory process, an increase in C-reactive protein and a reduction in IL-10 were observed. With respect to hormonal markers, an increase in cortisol and reduced levels of free T4 and bioavailable testosterone were found after exposure, with recovery of testosterone levels in the final week of training. Thermoregulatory adaptation of the organism has been associated with changes in heat flow in the organism in people subjected to extreme temperatures, with emphasis on the performance of the lower limbs. Our findings demonstrate an inflammatory response with hormonal changes after exposure to fire and an adaptive response of thermal balance, which could aid understanding of the physiology of the human body in extreme situations.

New insights about species delimitation in red snappers (Lutjanus purpureus and L. campechanus) using multilocus data

Lutjanus campechanus and Lutjanus purpureus are two commercially important lutjanid fishes (snappers) with non-sympatric distribution throughout Western Atlantic. Even though both taxa have traditionally been regarded as valid species, their taxonomic status remains under debate. In the present study, we used phylogeographic approaches and molecular methods of species delimitation to elucidate the taxonomic issues between both species, based on 1478 base pairs from four genomic regions. We found haplotypes shared between the two species, particularly in relation to nuclear DNA (nuDNA) sequences. The molecular delimitation of species supported the discrimination of L. purpureus and L. campechanus as distinct evolutionary units. Nonetheless, a unidirectional gene flow was found from L. campechanus towards L. purpureus. Therefore, it seems plausible to infer that L. campechanus and L. purpureus are two evolutionary units in which the apparent sharing of haplotypes should be driven by introgression.

Forensic analysis reveals fraud in fillets from the "Gurijuba" Sciades parkeri (Ariidae - Siluriformes): a vulnerable fish in Brazilian Coastal Amazon

The utilization of molecular tools for the certification of fishery products has been increasing over the last years. In general, economically important species are replaced by less valuable species, characterizing a commercial fraud. We evaluated the authenticity of 107 frozen fillets tagged as Gurijuba (Sciades parkeri) and Uritinga (Sciades proops) from local markets in northern amazon coast by sequencing two mitochondrial genes: Cytochrome oxidase subunit I and cytochrome b (Cyt b). About 16% of fillets putatively related to S. parkeri were replaced by S. proops. The Gurijuba faces high fishing pressure, being currently listed by the International Union for Conservation of Nature as vulnerable. Forensic analysis with DNA markers, proved to be highly efficient in the discrimination of the processed seafood products, providing unequivocal identification of species, revealing commercial fraud in the fillets of the Gurijuba, and revealing the utility of Cytb sequences as barcode in fishes.

Genomics overrules mitochondrial DNA, siding with morphology on a controversial case of species delimitation

Species delimitation is a major quest in biology and is essential for adequate management of the organismal diversity. A challenging example comprises the fish species of red snappers in the Western Atlantic. Red snappers have been traditionally recognized as two separate species based on morphology: Lutjanus campechanus (northern red snapper) and L. purpureus (southern red snapper). Recent genetic studies using mitochondrial markers, however, failed to delineate these nominal species, leading to the current lumping of the northern and southern populations into a single species ( L. campechanus). This decision carries broad implications for conservation and management as red snappers have been commercially over-exploited across the Western Atlantic and are currently listed as vulnerable. To address this conflict, we examine genome-wide data collected throughout the range of the two species. Population genomics, phylogenetic and coalescent analyses favour the existence of two independent evolutionary lineages, a result that confirms the morphology-based delimitation scenario in agreement with conventional taxonomy. Despite finding evidence of introgression in geographically neighbouring populations in northern South America, our genomic analyses strongly support isolation and differentiation of these species, suggesting that the northern and southern red snappers should be treated as distinct taxonomic entities.

Multiloci analyses suggest synonymy among Rhomboplites, Ocyurus and Lutjanus and reveal the phylogenetic position of Lutjanus alexandrei (Lutjanidae: Perciformes)

ABSTRACT Lutjanidae comprises 21 genera and 135 species widespread throughout Atlantic, Indian and Pacific oceans. Nonetheless, the phylogenetic relationships of Lutjaninae remain uncertain. Furthermore, phylogenetic hypotheses for Lutjanus alexandrei, an endemic species from northeastern Brazilian coast, in Lutjanidae are absent so far. Therefore, we carried out multiloci analyses, combining both mitochondrial and nuclear DNA sequences in Lutjaninae species from Western Atlantic focusing on the controversial relationships among Lutjanus, Rhomboplites, and Ocyurus. Besides, we determined the phylogenetic position and dated the origin of L. alexandrei. The phylogenetics trees based on the 4.4 kb for 11 species corroborated the synonym among Lutjanus and the putative monotypic genera. For the dating of L. alexandrei, another nucleotide dataset (3.0 kb; 40 species) validated the genetic identity of this species that diverged from the sister taxon L. apodus between 2.5 - 6.5 Mya, probably as a result of the barrier caused by the muddy outflow from Orinoco and Amazon rivers along the coastal zone. This report is the most robust multiloci analysis to confirm the synonymy of the three genera of Lutjaninae from Western Atlantic and the first reliable inference about the phylogenetic relationships and origin of L. alexandrei.

Molecular authentication of Pargo fillets Lutjanus purpureus (Perciformes: Lutjanidae) by DNA barcoding reveals commercial fraud

ABSTRACT The Caribbean Red Snapper (Pargo) Lutjanus purpureus is the most economically important snapper in Brazil, which is sold, among other forms, as frozen fillets. During the process of transformation into fillets there is the removal of the distinctive morphological traits, being able to favor the substitution by less valued species. In addition, there is no national legislation requiring the insertion of the specific name on the product label. However, according to a Normative Instruction (IN N ° 29/2015 MAPA) that correlates the common and specific names of the products destined to the national trade, in Brazil only L. purpureus and L. campechanus can be denominated “Pargo”. Thus, the DNA barcode tool was used to identify the fillets sold in north of Brazil, labeled “Pargo”, with the aid of sequences from the public and control databases. The results showed that among 142 fillets examined, 78% was identified as L. purpureus and 22% as Rhomboplites aurorubens, a snapper with low commercial value in the country, revealing commercial fraud. The molecular identification method successfully used in this study to authenticate fillets snappers may also be used by surveillance authorities in the quality control of processed fish products, towards ensuring consumer rights.

Comparative analyses of species delimitation methods with molecular data in snappers (Perciformes: Lutjaninae)

The integration of approaches that allow the incorporation of stochasticity of gene histories with phylogenetic methods resulted in new approaches for the old issue of species delimitation. Nevertheless, coalescent methods seem problematic for taxa with large effective population size and shallow temporal diversification (like marine fishes). Here, we investigate the performance of single-locus (cytochrome oxidase 1, commonly used in DNA barcoding initiatives) methods for molecular species delimitation in snappers of Lutjaninae from the Western Atlantic and Pacific Eastern. Our results show incongruences among methods. ABGD, PTP and mPTP trend towards a lower number of estimated species. Phylogenetic-coalescent methods with single threshold were majority congruent for a same number of lineages. On the other hand, algorithms with multiple thresholds tend to estimate a higher number of potential species. We do not endorse the use of single-locus for species delimitation, but we do reinforce that single-locus data is sufficient to flag many problems.

Development of EPIC-PCR Markers for Lutjanus purpureus (Lutjanidae-Perciformes) and their Potential Applicability in Population Analyses

In the present study, a novel set of eight EPIC primers were developed for Lutjanus purpureus and assayed in five other marine teleosts including three lutjanids, one scianid and one anablepid. Most of the genomic regions used in this study presented genetic diversity indexes equal or greater than the intragenic regions commonly used in population genetics studies. Moreover, six out of eight markers showed cross-amplification with other taxa. Thus, the primers described here may be used to elucidate questions at the intraspecific level for a large number of taxa.

High levels of genetic connectivity among populations of yellowtail snapper, Ocyurus chrysurus (Lutjanidae-Perciformes), in the western South Atlantic revealed through multilocus analysis

In the present study, five loci (mitochondrial and nuclear) were sequenced to determine the genetic diversity, population structure, and demographic history of populations of the yellowtail snapper, Ocyurus chrysurus, found along the coast of the western South Atlantic. O. chrysurus is a lutjanid species that is commonly associated with coral reefs and exhibits an ample geographic distribution, and it can therefore be considered a good model for the investigation of phylogeographic patterns and genetic connectivity in marine environments. The results reflected a marked congruence between the mitochondrial and nuclear markers as well as intense gene flow among the analyzed populations, which represent a single genetic stock along the entire coast of Brazil between the states of Pará and Espírito Santo. Our data also showed high levels of genetic diversity in the species (mainly mtDNA), as well a major historic population expansion, which most likely coincided with the sea level oscillations at the end of the Pleistocene. In addition, this species is intensively exploited by commercial fisheries, and data on the genetic structure of its populations will be essential for the development of effective conservation and management plans.

Small bowell perforation and mesentery injury after an unusual blunt abdominal trauma-Case report

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Blunt abdominal trauma after injury with a straw of bale in a rural hospital.

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Prompt evaluation with FAST and computed tomography did not show small bowell perforation.

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Despite this the patient went to surgery wich revealed jejunal perforation.

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Missed or another perforation needing re-surgery.

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Highly clinical suspicion depending on the mechanism of abdominal trauma.

Introduction

In blunt abdominal trauma, lesions of the small bowell and mesentery are often underdiagnosed; although unusual, they represent the third most injured organ, with increasing morbidity and mortality.

Presentation of case

The authors present the case of a 68 years old male, admitted to the emergency department after being hit by a bale of straw, weighing around 300 kg, in the abdomen. After successful ressuscitation, a CT scan was performed, suggesting hemoperitoneum because of vascular lesion of the right colon bleeding. An exploratory laparotomy was performed, confirming the presence of blood in the abdominal cavity and identifying jejunal perforation, an apparently innocent hematoma of the small bowel mesentery (beside the bowel wall) distally to the first lesion and a laceration of the sigmoid serosa; a segmental jejunal resection and suture of the colon serosa were performed. In the early post-operative period, an enteric discharge was noticed, mandating surgical reexploration; a previously unnoticed bowel perforation, in the mesenteric border where the hematoma was identified, justified an additional enterectomy, after what the patients recovery progressed uneventfully.

Discussion

In this case, a sudden increase in abdominal pressure could explain that missed rupture of the mesenteric border of the jejunum, also causing the mesenteric hematoma, or, in spite of that, a state of low perfusion could have lead to total wall ischemia of an already irrigation compromised segment.

Only noted after surgical exploration, despite prior evaluation with a computed tomography. Small bowell and mesenteric injuries are potentially missed due to decreased exploratory laparotomies for blunt abdominal trauma.

Conclusion

Although uncommon, small bowel and mesenteric injuries are associated with high morbidity and mortality. High clinical suspicion is essential for an early diagnosis

Web-based participatory surveillance of infectious diseases: the Influenzanet participatory surveillance experience

To overcome the limitations of the state‐of‐the‐art influenza surveillance systems in Europe, we established in 2008 a European‐wide consortium aimed at introducing an innovative information and communication technology approach for a web‐based surveillance system across different European countries, called Influenzanet. The system, based on earlier efforts in The Netherlands and Portugal, works with the participation of the population in each country to collect real‐time information on the distribution of influenza‐like illness cases through web surveys administered to volunteers reporting their symptoms (or lack of symptoms) every week during the influenza season. Such a large European‐wide web‐based monitoring infrastructure is intended to rapidly identify public health emergencies, contribute to understanding global trends, inform data‐driven forecast models to assess the impact on the population, optimize the allocation of resources, and help in devising mitigation and containment measures. In this article, we describe the scientific and technological issues faced during the development and deployment of a flexible and readily deployable web tool capable of coping with the requirements of different countries for data collection, during either a public health emergency or an ordinary influenza season. Even though the system is based on previous successful experience, the implementation in each new country represented a separate scientific challenge. Only after more than 5 years of development are the existing platforms based on a plug‐and‐play tool that can be promptly deployed in any country wishing to be part of the Influenzanet network, now composed of The Netherlands, Belgium, Portugal, Italy, the UK, France, Sweden, Spain, Ireland, and Denmark.

Molecular data indicate the presence of a novel species of Centropomus (Centropomidae - Perciformes) in the Western Atlantic

Centropomus undecimalis is distributed in the coastal waters of the western Atlantic between North Carolina and São Paulo, although very little is known of the genetic structure of its populations. Here, 148 C. undecimalis samples were obtained from six sites in the southwestern Atlantic, representing the Brazilian distribution of this species. Segments of three mitochondrial (Cytb, COI and 16S) and one nuclear (IGF1) gene were sequenced. The results of all analyses indicated the presence of a previously undetected lineage of Centropomus in the northern extreme of Brazil (Amapá) in the region of the Oiapoque estuary. This taxon is genetically distinct from all 12 recognized species of Centropomus. The populations from the Brazilian states of Pará, Maranhão, Ceará, Rio Grande do Norte, Rio de Janeiro and São Paulo were genetically similar to C. undecimalis from coastal areas of the Caribbean and USA. Nucleotide divergence between C. undecimalis and the new Oiapoque taxon are greater than or similar to those found between a number of valid Centropomus species. The estimated time of divergence between C. undecimalis and the new taxon is approximately 2 millionyears. The findings of the present study emphasize the need for a thorough taxonomic revision of this genus.

Population Structure of Lutjanus purpureus (Lutjanidae - Perciformes) on the Brazilian coast: further existence evidence of a single species of red snapper in the western Atlantic

The present study focus on the mitochondrial control region to investigate phylogeographic patterns and population structure in Lutjanus purpureus, and to evaluate the genetic similarity between L. purpureus and L. campechanus. For the initial analysis, 810 base pairs sequence from control region were obtained from 239 specimens of L. purpureus collected from four localities off the Brazilian coast. The results revealed the presence of a single panmictic population characterized by high values of genetic diversity. The 299 base pairs hypervariable portion were used for the combined analysis of L. purpureus and L. campechanus, being 275 haplotypes identified in the 414 specimens. Phylogenetic tree and haplotype network did not indicate phylogeographic substructuring between the two species, but rather an intense intermingling of individuals. Considering their marked morphological similarity, the molecular data presented here indicate that only one species of red snapper exists in the western Atlantic.

Comparative study of bipolar eletrocoagulation versus argon plasma coagulation for rectal bleeding due to chronic radiation coloproctopathy

BACKGROUND AND STUDY AIM

Chronic radiation coloproctopathy (CRCP) is a well-recognized complication of radiotherapy, with rectal bleeding the most common presentation. It is frequently refractory to conservative management, but the optimal endoscopic treatment of bleeding secondary to CRCP is still controversial. The efficacy and safety of bipolar eletrocoagulation (BEC) and argon plasma coagulation (APC) in the management of bleeding from CRCP were evaluated and compared.

PATIENTS AND METHODS

30 patients (mean age 67.4 years) with active and chronic bleeding from telangiectasias, were randomly allocated to BEC or APC and stratified by severity of CRCP according to clinical severity and endoscopic findings (Saunders score). Success was defined as eradication of all telangiectasias, and therapeutic failure as need for more than seven sessions or for other treatment. Complications were categorized as minor (e.g. fever, anal or abdominal pain) or major (hemorrhagic).

RESULTS

Both treatments were equally effective for the treatment of CRCP rectal bleeding. Only one failure was observed in each group (P = 1.000). There was no significant difference between the two groups regarding number of sessions, minor or major complications, or relapse. However, overall complication rate was significantly higher in the BEC group (P = 0.003).

CONCLUSIONS

BEC and APC are both effective for the therapy of bleeding telangiectasias from CRCP. There are probably no major differences between them. Although APC seemed safer than BEC in this investigation, further studies, involving a much larger population, are needed to assess the complication rates and determine the best management option.

The incidence of bacteraemia after argon plasma coagulation in patients with chronic radiation proctocolitis

AIM

Argon plasma coagulation (APC) is considered a safe treatment for haemorrhagic chronic radiation proctocolitis (CRPC), but bacteraemia is a rare complication. The study aimed to evaluate the frequency of bacteraemia after APC.

METHOD

A prospective study of 21 patients who underwent APC (30 procedures) for CRPC was carried out. Blood cultures (Bactec(®) ) were obtained before and 30 min after the procedure (60 samples total). Patients were monitored for 48 h after the procedure to detect signs of infection.

RESULTS

None of the 21 patients had fever or any sign suggestive of infection after any of the 30 sessions. All baseline blood cultures were negative and two (7%) of the 30-min blood cultures were positive (Staphylococcus hominis n = 1; Streptococcus bovis and Rhodotorula sp n = 1). The first was likely to be a contaminant and the second patient had no evidence of any other colonic disease (neoplasia or polyps) beside CRPC.

CONCLUSION

APC is a low-risk procedure regarding bacteraemia and does not warrant prophylactic antibiotic administration.

Severe malaria--clinical case

We report a clinical case of severe malaria, where the rate of initial parasitaemia by Plasmodium falciparum was 43 %. Multiple organ dysfunction, including ARDS, forced admission in a close surveillance unit, with survival of the same. A brief review of the subject is made, focusing on severity and general conduct, alerting and awareness for this entity, whose expression, among us, could take on increasing importance.

Bond strength and nanoroughness assessment on human pretreated cementum surfaces

OBJECTIVES

To determine the bond strength of seven adhesive systems to human cementum, and to assess the promoted surface roughness.

METHODS

Extracted human canines were used for the present study. The mesial surface from the cervical third of the roots were ground flat with wet 600-grit silicon carbide paper and bonded. Seven adhesive systems were employed: an etch-and-rinse adhesive (Single Bond), two two-step self-etching (Clearfil SE Bond and Resulcin Aquaprime) and four one-step self-etching (One-up Bond F, Prompt-L-Pop, Etch and Prime 3.0 and NRC+Prime&Bond NT). Composite build-ups were constructed and stored in a humid environment for 24h at 37 degrees C. Specimens were sectioned into 1mm(2) beams and tested for microtensile bond strength (MTBS). Additional surfaces were conditioned for atomic force microscopy (AFM) analysis. Results were analyzed with ANOVA and Student-Newman-Keuls tests (P<0.05).

RESULTS

Single Bond showed the highest MTBS values. No differences were found between Resulcin Aquaprime, One-up Bond and Prompt-L-Pop. Clearfil SE Bond, Etch and Prime and NRC+Prime&Bond NT obtained the lowest bond strength values. H(3)PO(4) acid treatment of cementum and Resulcin Aquaprime showed the highest nanoroughness parameters and One-up Bond the lowest.

CONCLUSION

The etch-and-rinse adhesive and the two-step self-etching adhesive with the lowest pH value promoted the highest bond strength to human cementum surfaces.

A preliminary study of insect fauna on pig carcasses located in sugarcane in winter in southeastern Brazil

Minimum post-mortem intervals can be estimated based on analyses of the pattern of insect succession on a carcass. In order to successfully apply this approach, insect development rates must be considered with regard to local regional climatic conditions. This study is the first to analyse insect succession on carcasses decomposing in a sugarcane crop in Brazil. In all seasons, Chrysomya albiceps (Wiedemann) (Diptera: Calliphoridae) and Cochliomyia macellaria (Fabricius) were frequent visitors during the fresh and bloated stages of decomposition, whereas Dermestes maculatus (De Geer) (Coleoptera: Dermistdae), Necrobia rufipes (De Geer) (Coleoptera: Cleridae) and Oxelytrum sp. (Coleoptera: Silphidae) were characteristic at the most advanced decomposition stages. The fact that climatic variations influence the occurrence of insect species and vegetation in the tropics may help to solve crimes through sampling of the local insect fauna, as may the fact that only certain groups of insects occur in specific regions of large countries like Brazil.

Comparison of the antibody in lymphocyte supernatant (ALS) and ELISPOT assays for detection of mucosal immune responses to antigens of enterotoxigenic Escherichia coli in challenged and vaccinated volunteers

In the present study we compared the ELISPOT and antibody in lymphocyte supernatants (ALS) assays as surrogate measures of mucosal immunity. In separate studies, 20 inpatient volunteers received oral doses of 6 x 10(8) or 4 x 10(9)cfu of ETEC strain E24377A (LT+, ST+, CS1+, CS3+) and 20 subjects received 1 (n = 9) or 2 (n = 11) oral doses of the attenuated ETEC vaccine, PTL-003 expressing CFA/II (CS1+ and CS3+) (2 x 10(9)cfu/dose). Peripheral blood mononuclear cells (PBMCs) from all subjects were assayed for anti-colonization factor or toxin-specific IgA antibody responses using the ALS and ELISPOT procedures. ALS responses were measured using a standard ELISA, as well as by time-resolved fluorescence (TRF). Following challenge with E24377A, significant anti-CS3, CS1 and LT ALS responses were detected in the lymphocyte supernatants of 75-95% of the subjects. A similar proportion (75%) of subjects mounted an ALS response to CFA/II antigen after vaccination with the PTL-003 vaccine. Inter-assay comparisons between ALS and ELISPOT methods also revealed a high degree of correlation in both immunization groups. ALS sensitivity versus the ELISPOT assay for LT, CS3 and CS1-specific responses following challenge were 95%, 94% and 78%, respectively and 83% for the ALS response to CFA/II antigen after vaccination with PTL-003. Correlation coefficients for the LT and CS3 antigens were 0.94 (p<0.001) and 0.82 (p<0.001), respectively after challenge and 0.78 (p<0.001) after vaccination. The association between ALS and ELISPOT for the CS1 antigen was however, significant only when ALS supernatants were tested by TRF (r = 0.91, p<0.001). These results demonstrate the value and flexibility of the ALS assay as an alternative to ELISPOT for the measurement of mucosal immune responses to ETEC antigens, particularly when the complexities of ELISPOT may make it impractical to perform.

Safety and immunogenicity of an oral, inactivated, whole-cell vaccine for Shigella sonnei: preclinical studies and a Phase I trial

Orally delivered, inactivated whole-cell vaccines are safe methods of inducing local and systemic immunity. To increase surface proteins associated with adherence and invasion, Shigella sonnei were grown in BHI broth containing deoxycholate. A whole-cell vaccine (SsWC) was then produced by formalin inactivation. In pre-clinical studies, the SsWC vaccine was immunogenic and protected against S. sonnei-induced keratoconjunctivitis in the guinea pig model. In a randomized, double-blind, placebo-controlled, Phase I study, 10 evaluable subjects received either three doses of SsWC on Days 0, 14, and 28 (N = 3); five doses of SsWC on Days 0, 2, 4, 6, and 28 (N = 4); or placebo (N = 3). Each dose contained 2.0 x 10(10) inactivated cells. Serum and fecal antibodies against SsWC, LPS, and IpaC were measured by ELISA. A > or = 4-fold increase in titer was considered significant. Both SsWC dosing regimens were well tolerated. No fever or severe gastrointestinal symptoms were noted by any of the vaccinated subjects. Antibody responses were similar in the two dosing groups. Serum IgG or IgA responses to SsWC were seen in six of seven vaccinees (86%), to LPS in four of seven (57%), and to IpaC in five of seven (61%). Fecal IgA responses to these three antigens developed in five of five, three of five, and three of five subjects, respectively. Among the seven vaccinees, geometric mean rises in serum IgA levels to all three immunogens were significant; IgG increases trended toward significance (paired one-tailed t-test). We conclude that SsWC was immunogenic and protective in animal studies and well tolerated and immunogenic in a Phase I trial.

Effect of calcium removal on dentin bond strengths

OBJECTIVE

The purpose of this in vitro study was to determine the microtensile bond strengths (mu TBS) of 3 dental adhesives when applied to dentin decalcified with ethylenediaminetetraacetic acid (EDTA). The null hypothesis tested was that the removal of calcium from dentin would not influence the bond strengths.

METHOD AND MATERIALS

Eighteen extracted human molars were cut in 2 equal halves. One half served as the control, having no EDTA treatment, while the other half was assigned to 1 of 3 periods (1 hour, 24 hours, or 100 hours) of decalcification with buffered 0.5 mol/L EDTA. Middle dentin was bonded with 1 of 3 dentin adhesive groups: a self-etching primer, Clearfil SE Bond (SE); an acetone-based total-etch adhesive, Prime&Bond NT (NT); and an ethanol- and water-based total-etch adhesive, Single Bond (SB). The specimens were restored with Z-250 resin composite and sectioned in 0.9 +/- 0.2 mm2 sticks that were tested in tensile mode.

RESULTS

For each adhesive, the control group (not decalcified) resulted in statistically higher bond strengths than the treatment groups. For specimens that were not decalcified, SE and SB had statistically similar bond strengths, but both resulted in statistically higher bond strengths than NT. For specimens decalcified for 1 hour, SE resulted in statistically higher bond strengths than either SB or NT, which were ranked in the same statistical group. SE was the only dentin adhesive to result in measurable mu TBS after decalcification with EDTA for 24 hours, while SB/24 hour and NT/24 hour specimens debonded spontaneously prior to testing. All the specimens treated with EDTA for 100 hours debonded prior to testing.

CONCLUSION

Three conclusions were drawn: (1) All 3 adhesive systems included in this project bonded significantly better to calcified than to decalcified dentin, regardless of their composition; (2) The self-etching primer-based adhesive ranked consistently equal to or better than the 2 total-etch-based adhesives, regardless of the EDTA decalcification time; and (3) Removal of calcium may be more detrimental for adhesives that rely on dentin acid etching than for adhesives based on self-etching primers.

Bond strengths of new simplified dentin-enamel adhesives

PURPOSE

To compare the in vitro shear bond strengths (SBS) of five simplified dentin adhesives. The tested hypothesis was that the recently introduced simplified adhesive systems would have similar or higher SBS than an existing simplified acetone-based adhesive used as a control.

MATERIALS AND METHODS

100 flat bonding sites were polished to 600-grit on the labial surface of bovine incisors mounted in acrylic resin. 50 teeth were ground to expose enamel, while the remaining 50 specimens were prepared to expose middle dentin. The specimens were randomly divided into five equal groups to be treated with simplified dentin adhesives: Dentastic Uno, EasyBond, Gluma One Bond, One Coat Bond, and One-Step (control). A composite post was bonded to each treatment area. After thermo-cycling, enamel and dentin shear bond strengths were determined using an Instron testing machine and the data were submitted to statistical analyses.

RESULTS

Mean enamel bond strengths ranged from 14.6-28.4 MPa. One Coat Bond had the highest mean enamel SBS, but it was not significantly higher than those of Gluma One Bond and Dentastic Uno. EasyBond and One-Step had statistically similar mean enamel SBS and these were significantly lower than the mean enamel SBS of the other three adhesives. For dentin, mean SBS ranged from 14.8-21.7 MPa. Dentastic Uno had the highest mean dentin SBS, but it was not significantly greater than those of One Coat Bond and Gluma One Bond. Although One Step had the lowest mean dentin SBS, it was not significantly different from those of either EasyBond or Gluma One Bond.