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Impacted third molar extraction is associated with acute moderate-to-severe pain for up to 48 hours post-surgery. This trial was designed to compare the analgesic effectiveness, swelling, and adverse events after impacted third molar surgery following multimodal therapy with 75 mg tramadol hydrochloride plus 25 mg dexketoprofen or monotherapy with 400 mg ibuprofen. Seventy-two patients were randomly assigned to receiving ibuprofen (n = 36) or tramadol-dexketoprofen (n = 36). Postoperative pain intensity and swelling were measured using a visual analog scale (VAS); pain relief experienced was reported using a 4-point verbal rating scale; the rescue medication requirement, adverse effects, and global impression of the medication were recorded. No statistically significant between-group difference in pain intensity was observed at any time point; however, pain relief was significantly higher in the tramadol-dexketoprofen treated-group at 6 and 36 hours. Self-reported verbal rating scale assessments showed significantly lower swelling in the tramadol-dexketoprofen group at 24 hours post-surgery but not at 48 or 72 hours, and VAS-swelling scores showed no significant between-group difference. The frequency of postoperative nausea and dizziness was significantly higher in the tramadol-dexketoprofen group. Multimodal therapy proved more effective to manage moderate-severe pain after impacted third molar surgery in comparison to monotherapy. However, the improvement in relief must be balanced against the increased risk of adverse effects when considering this multimodal approach. [ABSTRACT FROM AUTHOR]

Abstract: The majority of Shiga toxigenic Escherichia coli (STEC) strains isolated from severe STEC disease are those harboring the locus of enterocyte effacement (LEE), which encodes factors involved in adherence to epithelial cells. However, LEE-negative STEC are increasingly isolated from clinical cases. STEC autoagglutinating adhesin (Saa) is widely used as a marker of adhesin in the absence of LEE. In the present study, we compared the adherence of 32 saa-harboring STEC strains to cultured epithelial cells in the absence or presence of d-mannose. In the absence of d-mannose, 19 strains were adherent to HEp-2 and Caco-2 cells, while 12 were non-adherent. One strain showed detachment of epithelial cells. The adherence of 13 strains was sensitive to the presence of d-mannose. The saa mutant of strain T141, in which adherence was mannose resistant, did not show a significant decrease in adherence compared to the wild type, suggesting a Saa-independent mechanism of adherence. saa-harboring STEC exhibited differential binding properties to epithelial cells, which could not be attributed to the number of C-terminal repeats of Saa, or to the expression of Saa as detected by Western blotting. Our results suggest that multiple adherence mechanisms are present in saa-harboring STEC, implying a high degree of diversity in this group of STEC. [Copyright &y& Elsevier]

The objective was to state zinc contribution in the effectiveness of novel zinc-doped dentin cements to achieve dentin remineralization, throughout a literature or narrative exploratory review. Literature search was conducted using electronic databases, such as PubMed, MEDLINE, DIMDI, Embase, Scopus and Web of Science. Both zinc-doping silicate and hydroxyapatite-based cements provoked an increase of both bioactivity and intrafibrillar mineralization of dentin. Zinc-doped hydroxyapatite-based cements (oxipatite) also induced an increase in values of dentin nano-hardness, Young's modulus and dentin resistance to deformation. From Raman analyses, it was stated higher intensity of phosphate peaks and crystallinity as markers of dentin calcification, in the presence of zinc. Zinc-based salt formations produced low microleakage and permeability values with hermetically sealed tubules at radicular dentin. Dentin treated with oxipatite attained preferred crystal grain orientation with polycrystalline lattices. Thereby, oxipatite mechanically reinforced dentin structure, by remineralization. Dentin treated with oxipatite produced immature crystallites formations, accounting for high hydroxyapatite solubility, instability and enhanced remineralizing activity. Image 1 • Zn-doped silicate cements facilitate functional remineralization of dentin. • Zn-loaded hydroxyapatite cements remineralize and seal root dentin. • Zn promotes amorphous and stoichiometric apatites formation at dentin. [ABSTRACT FROM AUTHOR]

[Display omitted] • ML-doped polymeric nanoparticles avoided degradation of root dentin interface. • Undoped NPs provoked peak broadening and poor crystallinity with decreased hardness. • ML-NPs inducted preferred and randomly oriented crystallites influencing hardness. To investigate the effect of novel polymeric nanoparticles (NPs) doped with melatonin (ML) on nano-hardness, crystallinity and ultrastructure of the formed hydroxyapatite after endodontic treatment. Undoped-NPs and ML-doped NPs (ML-NPs) were tested at radicular dentin, after 24 h and 6 m. A control group without NPs was included. Radicular cervical and apical dentin surfaces were studied by nano-hardness measurements, X-ray diffraction and transmission electron microscopy. Mean and standard deviation were analyzed by ANOVA and Student-Newman-Keuls multiple comparisons (p < 0.05). Cervical dentin treated with undoped NPs maintained its nano-hardness values after 6 m of storage being [24 h: 0.29 (0.01); 6 m: 0.30 (0.02) GPa], but it decreased at apical dentin [24 h: 0.36 (0.01); 6 m: 0.28 (0.02) GPa]. When ML-NPs were used, nano-hardness was similar over time [24h: 0.31 (0.02); 6 m: 0.28 (0.03) GPa], at apical dentin. Root dentin treated with ML-NPs produced, in general, high crystallinity of new minerals and thicker crystals than those produced in the rest of the groups. After 6 m, crystals became organized in randomly oriented polyhedral, square polygonal block-like apatite or drop-like apatite polycrystalline lattices when ML-NPs were used. Undoped NPs generated poor crystallinity, with preferred orientation of small crystallite and increased microstrain. New polycrystalline formations encountered in dentin treated with ML-NPs may produce structural dentin stability and high mechanical performance at the root. The decrease of mechanical properties over time in dentin treated without NPs indicates scarce remineralization potential, dentin demineralization and further potential degradation. The amorphous stage may provide high hydroxyapatite solubility and remineralizing activity. [ABSTRACT FROM AUTHOR]

Shiga toxin-producing Escherichia coli (STEC) is th etiological agent of gastrointestinal diseases as haemorrhagic colitis and haemolytic-uraemic syndrome (HUS). Shiga toxin (Stx) is the main virulence factor. There are two types, Stx1 and Stx2, and several subtypes. Other virulence factors are involved in pathogenesis. While O157:H7 is the predominant serotype, at present non-O157 STEC strains are increasingly recognized as foodborne pathogens worldwide. In Argentina, STEC O174 stands out as an emerging pathogen and is one of the four most prevalent non-O157 STEC serogroups. The aim of this study was to characterize 41 O174:[H21, H28] STEC strains isolated from animals, food, and humans. Isolates were characterized by stx genotyping, adhesion factors ( afa C, eae , iha , lpf O113 , saa , and tox B), additional toxins ( cdt V, ehx A, sub A) and clonal relationship by pulsed-field gel electrophoresis (PFGE). Among 30 O174:H21 strains, the most prevalent stx subtype was stx 2c (56.7%), and among 11 O174:H28 strains, the most prevalent was stx 2a (90.9%). Regarding virulence factors, all strains were positive for afa C gene and negative for eae and tox B genes. In O174:H21, the frequency of additional factors was lpf O113 (96.6%), iha (83.3%), ehx A and saa (10%), and sub A (3.3%), meanwhile in O174:H28 strains the frequency was iha and sub A (100%), lpf O113 (90.9%), ehx A and saa (90.9%), and cdt V (9.09%). By Xba l-PFGE, 29 patterns were established with 64.01% similarity and three clusters were detected. Given the fact that the O174 serogroup is a local emergent, it is important to study the virulence profiles to understand its potential pathogenicity. [ABSTRACT FROM AUTHOR]

Abstract: We describe the isolation and characterization of Shiga toxin (Stx)-producing Escherichia coli (STEC) O157:H7 from cooked and uncooked beef and chicken burgers and from chicken carcasses collected during sampling procedures in 2001 and 2002 in Buenos Aires City, Argentina. Of the 24 STEC O157:H7 strains isolated, 20 were recovered from 19 (6.8%) out of 279 samples of beef and chicken burgers, and 4 strains from 4 (10.3%) out of 39 chicken carcasses. The samples were analyzed following the USDA/FSIS 2002 method. The prevalent stx genotype was stx 2 and stx 2c (12 strains, 50%). All strains were characterized as eae and ehxA-positive. By XbaI-PFGE, the strains yielded 10 different patterns. Eighteen out of 24 strains were grouped in four clusters: #1 (4 strains, AREXHX01.0043), #2 (4 strains, AREXHX01.0022), #3 (8 strains, AREXHX01.0139), and #4 (2 strains, AREXHX01.0200). Identical strains by phage typing, stx genotyping and PFGE were detected in uncooked and cooked beef and chicken burgers in different restaurants, which had been collected on the same or different sampling dates. These findings help to underline the importance of STEC O157 detection in meat products, to improve active surveillance, and to define control strategies in order to prevent new cases of STEC infection. [Copyright &y& Elsevier]

Abstract: Long polar fimbriae (LPF) are related to type I fimbriae in genetic organization and were first identified in Salmonella enterica serovar Typhimurium. Four lpfA genetic variants designated lpfA O157/OI-141, lpfA O157/OI-154, lpfA O26 and lpfA O113 have been identified in Shiga toxin-producing Escherichia coli (STEC). In this study, PCR was employed to determine the distribution of STEC-lpfAs in enteropathogenic, enteroaggregative, enterotoxigenic and enteroinvasive E. coli (EPEC, EAEC, ETEC and EIEC) and in the standard E. coli collection of reference (ECOR). Among the 97 diarrheagenic strains from our collection, only 2 EPEC strains of serotypes O55:H7 and O119:NM were positive for both lpfA O157/OI-141 and lpfA O157/OI-154. lpfA O157/OI-141 was also positive in 1 of 25 ETEC strains. lpfA O113 was present in 51 of 97 strains and lpfA O26 in 13 of 97 strains of diverse diarrheagenic categories. STEC-lpfAs were also present in non-pathogenic ECOR strains of all phylogenetic groups. This study showed that the lpfA genes identified in the genome of STEC strains are not specific to this category. Our results suggest that there is a relationship between the lpfA variant and the phylogenetic group. [Copyright &y& Elsevier]

Between July 1999 and December 2000, the prevalence of Shiga toxin-producing Escherichia coli (STEC) was established in 200 Argentine healthy young beef steers (14–16 months old) grown under local production systems with a feed grain period of 3–4 months, and the STEC strains isolated were examined in regard to their phenotypic and genotypic characteristics.Stool samples (n=70) and rectal swabs (n=130) were taken at the slaughterhouse level.By polymerase chain reaction (PCR), Shiga toxin (stx) gene sequences were detected in 69% of the samples. Eighty-six STEC strains were isolated from 39% of the animals. Serogroups identified, in order of frequency, were: O8 (16 strains), O113 (14), O103 (5), O91 (4), O171 (3), O174 (3), O25 (2), O112 (2), O145 (2), O2, O11, O104, O121, O128, O143, O146, O157. The most frequent serotype isolated was O8:H19 (12.9%). A total of 17 serotypes, including E. coli O157:H7 found in one animal (0.5%), have been previously associated with hemolytic uremic syndrome (HUS), bloody and non-bloody diarrhea in different countries, including Argentina.The prevalent genotype isolated was stx2 (51 of 86, 59.3%). Subtyping of stx2 variants showed the prevalence of stx2vh-b (25.6%) and stx2vh-a types (24.4%), and revealed the presence of an atypical stx2-v. Only 7.0% of STEC strains carried eae, and 33.7% harbored EHEC-hlyA gene. The full virulent genotype (stx/eae/EHEC-hlyA) was found to be present in 4 of the 86 (4.7%) STEC strains isolated.This research indicates that young steers from the main beef-producing area of Argentina are an important reservoir of STEC strains; however, its importance as agents of human diseases in our country has still to be established. [Copyright &y& Elsevier]