Effect of exposure to 3,4,4′-Trichlorocarbanilide (TCC) during critical developmental life stages

Triclocarban (3,4,4\u27-trichlorocarbanilide; TCC) is a non-prescription antimicrobial compound found in bar soaps. Once applied to the skin, TCC is absorbed and can be detected systemically. Evidence of endocrine disruption has been documented both in vitro and in vivo in adult and immature rats. To date, little research attention has been paid to early life TCC exposure. Here, we demonstrated reduced survival among neonates born to rats provided 0.2 percent w/w or 0.5 percent w/w TCC supplemented chow during lactation. TCC was detected in the breastmilk and suckling neonates developed distended abdomens with liquid mustard colored diarrhea indicating a disturbance of the gut microbiota. When the concentration of TCC provided to dams through the chow was lowered to 0.1 percent w/w TCC, all neonates survived. However, sequencing of the V4 region of 16S rRNA on the MISeq platform revealed that TCC exposure modified the composition of the gut microbiota of suckling neonates. In addition, exposure to post-weaned rats at concentrations of 0.2 percent and 0.5 percent w/w TCC through the diet modified the gut microbial composition of older animals. Though, when exposure was removed from post-weaned rats, the compositional profile of microbial communities eventually rebounded and became more similar to samples collected from animals never exposed to TCC at subsequent collection dates. To better understand the exposure pathway of TCC to the gut microbiota, a method was developed to analyze the concentration of TCC in the rat fecal matrix. This dissertation collectively adds to the growing body of concern related to TCC exposure and provides information to both the general public and regulatory agencies on the safety of nonprescription antimicrobial use during early life

Equine oral microbiology

Until recently, equine oral microbiology was a relatively unexplored field. The role of bacteria in both oral health and in oral diseases such as periodontitis and dental caries has long been acknowledged in brachydont species such as humans, dogs and cats. The ecological community of bacteria, both commensal and pathogenic, inhabiting the oral cavity is known as the oral microbiome and has been well studied in humans. By 2010, the Human Oral Microbiome Database (HOMD) included approximately 700 prokaryote species that can be present in the human oral cavity. Recent work has also began to characterise the equine and donkey oral microbiome in order to gain a better understanding how these microbial communities are involved in maintaining oral health and also their potential role in the pathogenesis of a variety of equine oral diseases. Technical advances, especially the increased availability of molecular microbiology techniques have allowed insights into this previously neglected area. <br/

Equine “Idiopathic” and Infundibular Caries-Related Cheek Teeth Fractures: A Long-Term Study of 486 Fractured Teeth in 300 Horses

Background: Limited objective information is available on the prevalence of non-traumatic equine cheek teeth fractures, the signalment of affected horses, and the clinical features and treatment of these fractures. Objectives: This study aims to document patterns of idiopathic and infundibular caries-related cheek teeth fractures in a referral population and evaluate associations between fracture patterns and horse age, Triadan position of affected teeth, clinical signs, and deemed necessity for treatment. Study Design: A retrospective case review. Methods: The clinical records at Edinburgh University Veterinary School (2010–2018) were examined for the presence of non-traumatic equine cheek teeth fractures. Variations in the frequencies of different fracture patterns were compared between horse ages, Triadan tooth positions, clinical signs, and deemed necessity for treatment. Results: Records of 300 horses with 486 non-traumatic cheek teeth fractures including 77% maxillary and 23% mandibular teeth with a mean of 1.6 (range 1–10) fractured teeth/horse were available. Fracture patterns included maxillary first and second pulp horn (“slab”) cheek teeth fractures (n = 171), caries-related infundibular fractures (n = 88), other maxillary teeth fracture patterns (n = 92), mandibular first and second pulp horn (“slab”) fractures (n = 44), other mandibular fracture patterns (n = 62), and complete clinical crown loss (n = 29; including 23 maxillary and 6 mandibular teeth). The median age of affected horses ranged from 11 years with maxillary “slab” fractures to 15 years with infundibular caries-related fractures. Triadan 08–10s were the most commonly (86%) fractured maxillary teeth. The Triadan 08 and 09 positions were the most commonly (64%) fractured mandibular teeth. No clinical signs were noted in horses with 48% of the fractured teeth; oral pain/quidding was recorded with 26%, clinical apical infection with 23%, and bitting/headshaking problems with 6%. Treatments included extraction of 40% fractured teeth, extraction of small/loose fragments (10%), and odontoplasty. Stable remnants of 60% of fractured teeth were left in horses without clinical signs. Main Limitations: Long-term follow-up information was not available for all cases. Conclusions: There is increasing recognition of equine non-traumatic cheek teeth fractures, with about half not causing clinical signs. Teeth with apical infection, multiple fractures, or advanced caries require extraction. Other fractured teeth with subclinical endodontic disease may not need exodontia unless they later cause clinical signs

Microbiological and immunological aspects of equine periodontal disease

Periodontal disease is a common and painful condition in the horse. Although awareness of the condition is growing amongst the veterinary profession and horse owners, the presence of the disease is often overlooked and treatment can be difficult. Despite this, there have been few recent studies of the aetiopathogenesis of the condition. Certain species of bacteria may act as periodontal pathogens, stimulating a destructive inflammatory response in periodontal tissues and this has been well recognised as being important to the aetiopathogenesis of the disease in man. However few equine studies on this aspect of the disease have been carried out. The main aims of this study were: - 1) to identify the bacteria associated with a healthy oral cavity and periodontitis in horses using culture dependent and independent methods; 2) to assess the differences in bacterial populations between the healthy and periodontitis groups and identify putative pathogens; 3) to quantify the expression patterns of TLRs 2, 4 and 9, the pro-inflammatory cytokines IL-1β and TNFα, anti-inflammatory cytokine IL-10 and Th1/Th2/Th17 cytokines IL-4, IL-6/ IL-12, IFNɣ/ IL-17, within gingival tissue from each sample group; 4) to use matched data to establish if associations exist between the presence and quantity of bacterial species present and TLR expression and 5) to determine activation of TLRs 2, 4 and 9 by putative pathogens using specific in- vitro TLR assays. Swabs were taken from the gingival sulcus of 42 orally healthy horses and plaque samples were taken from the periodontal pockets of 61 horses with periodontal disease. The location and grade of the lesion was noted and an equine dental chart completed for each case. Bacteria were identified using high throughput 16S rRNA gene sequencing, QPCR, whole genome sequencing and conventional culture followed by 16S gene sequencing. Gingival biopsies were taken from 13 orally healthy horses and 20 horses with periodontitis and gene expression of TLR 2, TLR 4, TLR 9, IL-1β, IL-4, IL-6, IL-10, IL-12, IL-17, TNFα and IFNɣ was measured. THP-1X Blue, MyD88 THP-1X Blue, HEK hTLR 2 Blue and HEK hTLR 4 Blue human cell lines were co-cultured with putative periodontal pathogens and their response measured via level of secreted embryonic alkaline phosphatase. Clinical, microbiological and immunological data underwent cross-matching analysis. Microbial populations showed 89% dissimilarly between oral health and periodontitis with a less diverse population present in diseased equine periodontal pockets. The most discriminative bacteria between health and disease identified at genus level were Fusobacteria and Acinetobacter in health and Pseudomonas and Prevotella in periodontitis. The most abundant genera were Gemella (36.5%), Pseudomonas (14%) and Acinetobacter (8%) in orally healthy samples and Pseudomonas (25%), Prevotella (14%) and Acinetobacter (9.4%) in periodontitis samples. Whole genome sequencing revealed the presence of 75 species of Prevotella in the equine oral cavity and a significantly higher number of reads corresponding to Prevotella bivia, Prevotella dentalis, Prevotella denticola, Prevotella intermedia, Prevotella melaninogenica, Prevotella nigrescens were noted in diseased samples. Significant increases in expression of TLR 4 mRNA, TLR 9 mRNA and, in particular TLR 2, mRNA were noted in diseased equine gingival tissue in addition to increased pro-inflammatory and anti-inflammatory cytokine mRNA expression. Presence of P. intermedia was significantly positively correlated with expression of TLR 2 in equine periodontitis. In addition, the presence of Aggregatibacter actinomycetemcomitans was positively associated with disease severity and expression of TLR 4 mRNA in the horse. Co-culture of periodontal pathogens with human cell lines revealed that the innate immune response to the presence of these bacteria is mainly mediated through TLR 2 activation. The use of both culture dependent and culture independent methods to investigate the equine oral microbiome has provided significant breadth and depth of information on the microbiology of equine periodontal disease. Microbial populations are significantly different as expected and bacteria belonging to the Prevotella genus have been strongly implicated in the aetiopathogenesis of the condition. The innate immune response produced in periodontally diseased equine gingival tissue has been characterised for the first time in the horse

The microbiome associated with equine periodontitis and oral health

Equine periodontal disease is a common and painful condition and its severe form, periodontitis, can lead to tooth loss. Its aetiopathogenesis remains poorly understood despite recent increased awareness of this disorder amongst the veterinary profession. Bacteria have been found to be causative agents of the disease in other species, but current understanding of their role in equine periodontitis is extremely limited. The aim of this study was to use high-throughput sequencing to identify the microbiome associated with equine periodontitis and oral health. Subgingival plaque samples from 24 horses with periodontitis and gingival swabs from 24 orally healthy horses were collected. DNA was extracted from samples, the V3–V4 region of the bacterial 16S rRNA gene amplified by PCR and amplicons sequenced using Illumina MiSeq. Data processing was conducted using USEARCH and QIIME. Diversity analyses were performed with PAST v3.02. Linear discriminant analysis effect size (LEfSe) was used to determine differences between the groups. In total, 1308 OTUs were identified and classified into 356 genera or higher taxa. Microbial profiles at health differed significantly from periodontitis, both in their composition (p &lt; 0.0001, F = 12.24; PERMANOVA) and in microbial diversity (p &lt; 0.001; Mann–Whitney test). Samples from healthy horses were less diverse (1.78, SD 0.74; Shannon diversity index) and were dominated by the genera Gemella and Actinobacillus, while the periodontitis group samples showed higher diversity (3.16, SD 0.98) and were dominated by the genera Prevotella and Veillonella. It is concluded that the microbiomes associated with equine oral health and periodontitis are distinct, with the latter displaying greater microbial diversity

Rapid Stereomicroscopic Imaging of HER2 Overexpression in Ex Vivo Breast Tissue Using Topically Applied Silica-Based Gold Nanoshells

Tumor margin detection for patients undergoing breast conservation surgery primarily occurs postoperatively. Previously, we demonstrated that gold nanoshells rapidly enhance contrast of HER2 overexpression in ex vivo tissue sections. Our ultimate objective, however, is to discern HER2 overexpressing tissue from normal tissue in whole, nonsectioned, specimens to facilitate rapid diagnoses. Here, we use targeted nanoshells to quickly and effectively visualize HER2 receptor expression in intact ex vivo human breast tissue specimens. Punch biopsies of human breast tissue were analyzed after a brief 5-minute incubation with and without HER2-targeted silica-gold nanoshells using two-photon microscopy and stereomicroscopy. Labeling was subsequently verified using reflectance confocal microscopy, darkfield hyperspectral imaging, and immunohistochemistry to confirm levels of HER2 expression. Our results suggest that anti-HER2 nanoshells used in tandem with a near-infrared reflectance confocal microscope and a standard stereomicroscope may potentially be used to discern HER2-overexpressing cancerous tissue from normal tissue in near real time and offer a rapid supplement to current diagnostic techniques

T cells enhance gold nanoparticle delivery to tumors in vivo

Gold nanoparticle-mediated photothermal therapy (PTT) has shown great potential for the treatment of cancer in mouse studies and is now being evaluated in clinical trials. For this therapy, gold nanoparticles (AuNPs) are injected intravenously and are allowed to accumulate within the tumor via the enhanced permeability and retention (EPR) effect. The tumor is then irradiated with a near infrared laser, whose energy is absorbed by the AuNPs and translated into heat. While reliance on the EPR effect for tumor targeting has proven adequate for vascularized tumors in small animal models, the efficiency and specificity of tumor delivery in vivo, particularly in tumors with poor blood supply, has proven challenging. In this study, we examine whether human T cells can be used as cellular delivery vehicles for AuNP transport into tumors. We first demonstrate that T cells can be efficiently loaded with 45 nm gold colloid nanoparticles without affecting viability or function (e.g. migration and cytokine production). Using a human tumor xenograft mouse model, we next demonstrate that AuNP-loaded T cells retain their capacity to migrate to tumor sites in vivo. In addition, the efficiency of AuNP delivery to tumors in vivo is increased by more than four-fold compared to injection of free PEGylated AuNPs and the use of the T cell delivery system also dramatically alters the overall nanoparticle biodistribution. Thus, the use of T cell chaperones for AuNP delivery could enhance the efficacy of nanoparticle-based therapies and imaging applications by increasing AuNP tumor accumulation

Size-controlled synthesis of monodispersed gold nanoparticles via carbon monoxide gas reduction

An in depth analysis of gold nanoparticle (AuNP) synthesis and size tuning, utilizing carbon monoxide (CO) gas as a reducing agent, is presented for the first time. The sizes of the AuNPs are tunable from ~4 to 100 nm by altering the concentration of HAuCl4 and inlet CO gas-injection flow rate. It is also found that speciation of aqueous HAuCl4, prior to reduction, influences the size, morphology, and properties of AuNPs when reduced with CO gas. Ensemble extinction spectra and TEM images provide clear evidence that CO reduction offers a high level of monodispersity with standard deviations as low as 3%. Upon synthesis, no excess reducing agent remains in solution eliminating the need for purification. The time necessary to synthesize AuNPs, using CO, is less than 2 min

Emotions and Complaining Behavior Following Service Failure

One feature of a democratic society is voice, especially the freedom to dissent. One form of dissent of relevance to organizational scholars is complaining, whether it be complaints from employee stakeholder groups or customer stakeholder groups. Despite the increased ability that the knowledge economy provides for people of all walks of life and nationalities to voice complaint, little is known about the antecedents and consequences of complaining. This paper addresses this issue with respect to customers' response to service failures. Specifically, this paper develops a conceptual model for service settings building upon a model of emotional and cognitive response formation to an affective event (Hartel, McColl-Kennedy & Bennett, 2002), and its source theory, Weiss and Cropanzano's (1995) Affective Events Theory (AET). We argue that when a service failure occurs, a number of cognitive and affective responses take place in consumers. The proposed model aims to operationalize affective responses to service failures in the marketplace. 'Affective response' refers to cognitive, emotional, behavioral and neuropsychological responses to emotional events. As such, the model makes explicit the relationships between and factors within each of these domains of affect expression