Immediate and long-term impact of the COVID-19 pandemic on delivery of surgical services.

BACKGROUND: The ongoing pandemic is having a collateral health effect on delivery of surgical care to millions of patients. Very little is known about pandemic management and effects on other services, including delivery of surgery. METHODS: This was a scoping review of all available literature pertaining to COVID-19 and surgery, using electronic databases, society websites, webinars and preprint repositories. RESULTS: Several perioperative guidelines have been issued within a short time. Many suggestions are contradictory and based on anecdotal data at best. As regions with the highest volume of operations per capita are being hit, an unprecedented number of operations are being cancelled or deferred. No major stakeholder seems to have considered how a pandemic deprives patients with a surgical condition of resources, with patients disproportionally affected owing to the nature of treatment (use of anaesthesia, operating rooms, protective equipment, physical invasion and need for perioperative care). No recommendations exist regarding how to reopen surgical delivery. The postpandemic evaluation and future planning should involve surgical services as an essential part to maintain appropriate surgical care for the population during an outbreak. Surgical delivery, owing to its cross-cutting nature and synergistic effects on health systems at large, needs to be built into the WHO agenda for national health planning. CONCLUSION: Patients are being deprived of surgical access, with uncertain loss of function and risk of adverse prognosis as a collateral effect of the pandemic. Surgical services need a contingency plan for maintaining surgical care in an ongoing or postpandemic phase.

ANTECEDENTES: La pandemia en curso tiene un efecto colateral sobre la salud en la prestación de atención quirúrgica a millones de pacientes. Se sabe muy poco sobre el manejo de la pandemia y sus efectos colaterales en otros servicios, incluida la prestación de servicios quirúrgicos. MÉTODOS: Se ha realizado una revisión de alcance de toda la literatura disponible relacionada con COVID-19 y cirugía utilizando bases de datos electrónicas, páginas web de sociedades, seminarios online y repositorios de pre-publicaciones. RESULTADOS: Se han publicado varias guías perioperatorias en un corto período de tiempo. Muchas recomendaciones son contradictorias y, en el mejor de los casos, se basan en datos anecdóticos. A medida que las regiones con el mayor volumen de operaciones per cápita se ven afectadas, se cancela o difiere un número sin precedentes de operaciones. Ninguna de las principales partes interesadas parece haber considerado cómo una pandemia priva de recursos a los pacientes que necesitan una intervención quirúrgica, con pacientes afectados de manera desproporcionada debido a la naturaleza del tratamiento (uso de anestesia, quirófanos, equipo de protección, contacto físico y necesidad de atención perioperatoria). No existen recomendaciones sobre cómo reanudar la actividad quirúrgica. La evaluación tras la pandemia y la planificación futura deben incluir a los servicios quirúrgicos como una parte esencial para mantener la atención quirúrgica adecuada para la población también durante un brote epidémico. La prestación de servicios quirúrgicos, debido a su naturaleza transversal y a sus efectos sinérgicos en los sistemas de salud en general, debe incorporarse a la agenda de la OMS para la planificación nacional de la salud. CONCLUSIÓN: Los pacientes se ven privados de acceso a la cirugía con una pérdida de función incierta y riesgo de un pronóstico adverso como efecto colateral de la pandemia. Los servicios quirúrgicos necesitan un plan de contingencia para mantener la atención quirúrgica durante la pandemia y en la fase post-pandemia.

Cigarette smoke modifies neutrophil chemotaxis, neutrophil extracellular trap formation and inflammatory response-related gene expression.

BACKGROUND AND OBJECTIVE: Cigarette smoking is a major risk factor for periodontitis, and smoking perturbs neutrophil reactive oxygen species production. This study tested the hypothesis that cigarette smoke extract (CSE) and its components/metabolites nicotine, cotinine and thiocyanate (SCN-), may influence neutrophil functions. MATERIAL AND METHODS: Chemotaxis was assessed in neutrophils pre-treated with CSE using real-time video microscopy. Neutrophil extracellular trap (NET) release in response to CSE, nicotine, cotinine, SCN- as well as to phorbol 12-myristate-13-acetate and hypochlorous acid following pre-treatment with CSE, nicotine, cotinine or SCN- was assessed using fluorescence-based assays. The impact of CSE and SCN- treatment on neutrophil respiratory burst- and inflammation-related gene expression (NFKBIE, DNAJB1, CXCL8, NCF1, NCF2, CYBB) was determined by real-time polymerase chain reaction. RESULTS: Both CSE and SCN- pre-treatment inhibited phorbol 12-myristate-13-acetate-stimulated NET release. Additionally, SCN- inhibited hypochlorous acid-stimulated NET formation, while SCN- alone stimulated NET release. Overall, neutrophils pre-treated with CSE exhibited reduced speed, velocity and directionality relative to untreated neutrophils. Although CSE and SCN- promoted DNAJB1 expression, increased redox-related gene expression was only detected in response to SCN-. CONCLUSION: These results suggest that CSE can alter ex vivo neutrophil activation by mechanisms independent of SCN- and nicotine, and SCN- may contribute to the perturbed innate immune responses observed in smokers.

Use of a saliva-based diagnostic test to identify tapeworm infection in horses in the UK.

BACKGROUND: Anthelmintic resistance combined with limited chemotherapeutic options has prompted a change in approaches to control of equine helminth infections. Targeted selective treatment strategies use diagnostics to reduce anthelmintic use by treating individuals with worm burdens or egg shedding levels above a set threshold. While faecal egg count analysis has limitations for informing tapeworm treatment, a commercially available saliva-based diagnostic test accurately diagnoses horses with tapeworm infection. OBJECTIVES: Evaluation of a saliva-based diagnostic test to identify horses naturally infected with tapeworm and assess the impact of using the test to inform anthelmintic administration. STUDY DESIGN: Retrospective longitudinal study. METHODS: Saliva was collected from horses (n = 237) at a UK welfare charity from autumn 2015 to autumn 2016. Horses diagnosed as positive for tapeworm infection using the EquiSal® Tapeworm test were anthelmintic treated according to weight. The number of horses that received anthelmintic treatment based on the test result was compared with an all-group treatment approach and the reduction in anthelmintic usage calculated. Incoming horses were also tested (n = 143) and the information was used to inform quarantine treatments. RESULTS: In autumn 2015, 85% of 237 horses tested received no anthelmintic and the majority (71%) of these remained below the treatment threshold throughout the study. Of the 69 horses that received treatment, seven required treatment following three subsequent tests, while >50% of horses administered with anthelmintic fell below the treatment threshold at the following test. No increase in tapeworm prevalence within the 237 horses was observed during the study despite a substantial reduction in the application of antitapeworm treatments. A total of 41% of incoming horses required anticestode treatment. MAIN LIMITATIONS: Other management practices were not included in the analysis. CONCLUSIONS: Compared with an all-group treatment strategy, the diagnostic-led approach used here considerably reduced application of anticestode anthelmintics. This could reduce selection pressure for anthelmintic resistance.

Pain Control, Glucose Control, and Quality of Life in Patients With Chronic Pancreatitis After Total Pancreatectomy With Islet Autotransplantation: A Preliminary Report.

BACKGROUND: Total pancreatectomy (TP) is offered as a last treatment option for pain relief in patients with chronic pancreatitis. Concurrent islets autotransplantation (TP-IAT) may improve glucose control. METHODS: We analyzed results in 20 recent patients who underwent TP-IAT at The University of Chicago. The median observation period was 28 months (2-38). Data were collected prospectively then analyzed retrospectively. RESULTS: The number of patients requiring opioids daily for pain control decreased from 16 (80%) prior to surgery to 2 (13%) 1 year after, with only 1 (6.5%) patient experiencing persistent phantom pancreatic pain. Opioid requirements decreased from a median 56.3 (0-240) morphine equivalent dose to 5 (0-130) on day 75 and to 0 (0-30) at 1-year follow up. Five patients (25%) completely stopped insulin support prior to day 75 while maintaining hemoglobin A1c of 5.9% (5-6.3). Eight (53%) patients were insulin free at 1 year with A1c of 6% (5.5-6.8) and a similar rate persisted in next 2 years. For the remaining patients, the more islet function that was preserved, the less insulin they required and A1c was closer to optimal. Quality of Life (QoL) measured by SF36 Physical (PCS) and Mental (MCS) Component Score improved on day 75 (P < .001) and maintained improvement later on. Both PCS and MCS improved regardless of whether patient requires insulin support or not. CONCLUSIONS: Improvements of QoL with pain resolution and good glucose control can be achieved after TP-IAT in properly selected patients with CP and intractable pain, regardless of patient insulin support status.

Papaya latex supernatant has a potent effect on the free-living stages of equid cyathostomins in vitro.

The control of equid gastrointestinal nematodes in developed countries, in particular the cyathostomins, is threatened by high levels of anthelmintic resistance. In recent years, there has been increasing interest in the evaluation of traditional 'ethnoveterinary' medicines as alternatives to chemical anthelmintics. The cysteine proteinases (CPs), a group of enzymes derived from fruits such as papaya (Carica papaya), pineapple (Ananas comosus) and figs (Ficus spp.), have shown good efficacy against adult stages of a range of parasitic nematodes, in vitro and in vivo. The efficacy of CPs against cyathostomins remains to be explored. In this study, the efficacy of a crude preparation of CPs, papaya latex supernatant (PLS), against the free-living stages of cyathostomins was evaluated using two in vitro tests, the egg hatch test (EHT) and the larval migration inhibition test (LMIT). It was demonstrated that PLS had a potent effect in the EHT, with EC-50 values in the range of 0.12-0.22µM. At concentrations above 6.25µM the eggs did not develop, below this concentration the L1 developed but they lost integrity of the cuticle upon hatching. These effects were inhibited by pre-incubation of PLS with the CP inhibitor L-trans-epoxysuccinyl-l-leucylamido-(4-guanidino butane) (E64), indicating that CPs were responsible for the anti-parasitic activity. A dose-dependent inhibition of migration of third stage larvae (L3) in the LMIT was demonstrated at higher concentrations of PLS, with EC-50 values in the range of 67.35-106.31µM. Incubation of PLS with E64 prior to use in the LMIT did not reverse the anti-migratory effect, suggesting that CPs were not responsible for the reduced migration of cyathostomin L3 and that PLS also contains an additional active compound. This is the first report of PLS and/or CPs showing activity against the free-living stages of a parasitic helminth. In addition, it suggests that cyathostomins are highly sensitive to the effects of CPs and further evaluation of their efficacy against parasitic stages and in vivo are strongly indicated.

Differential expression of TLR3 and TLR4 in keratocystic odontogenic tumor (KCOT): A comparative immunohistochemical study in primary, recurrent, and nevoid basal cell carcinoma syndrome (NBCCS)--associated lesions.

BACKGROUND: Toll-like receptors (TLRs) play an essential role in the activation of innate immunity and they can promote cancer cell survival and tumor progression. It has been claimed that TLRs can somehow predict the clinical behavior in oral squamous cell carcinoma (OSCCs). AIM: To elucidate the molecular basis underlying keratocystic odontogenic tumor (KOCTs) aggressive behavior and recurrence we carried out this immunohistochemical study on TLR3 and TLR4 expression in sporadic primary KCOTs (sp-KCOTs), sporadic recurrent KCOTs (sp-KCOTs), and NBCCS-associated KCOTs (NBCCS-KCOTs). METHOD: 40 cases of KOCTs removed from 23 men and 17 women were the sample. Paraffin-embedded blocks were processed for immunohistochemistry. Sections were incubated with TLR3 and TLR4 antibodies and immunoreactivity evaluated on a semi-quantitative score. RESULTS: Both TLR3 and TLR4 were expressed in KCOTs epithelium, although with a different extent. TLR3 was not expressed in sp-KCOTs and sr-KCOTs, but it showed a faint staining in NBCCS-KCOTs. On the other hand, both cytoplasmic and nuclear staining for TLR4 was detected in all the 3 types of lesions; however being significantly more expressed in sr-KCOT and NBCCS-KCOTs (p < 0.0001). Our results, demonstrated an association between TLR4, but not TLR3 expression to recurrence behavior of KCOTs. In fact, TLR4 was up-regulated in sr-KCOTs and NBCCS-KCOTs but not in sp-KCOTs. CONCLUSIONS: According these findings it seems conceivable to assume that the up-regulation of TLR4 in some KCOTs can be correlated somehow to their tendency recurrence.

Beta-catenin and survivin expression in keratocystic odontogenic tumor (KCOT). A comparative immunohistochemical study in primary, recurrent and nevoid basal cell carcinoma syndrome (NBCCS)-associated lesions.

AIM: To determine the epithelial expression of ß-catenin and survivin in sporadic (primary, and recurrent) and nevoid basal cell carcinoma syndrome (NBCCS) keratocystic odontogenic tumour (KCOT) in order to assess activation of the ß-catenin pathway and evidence of apoptotic inhibition, processes that may contribute to the known differences in their biological behaviour. MATERIALS AND METHODS: Sections from 40 cases of KCOT (19 sporadic/primary; 9 sporadic/recurrent and 12 NBCCS-associated) were immunohistochemically stained for ß-catenin and survivin. The extent and intensity of immunoreactivity within the lining epithelium was assessed, using semi-quantitative scales, independently by two pathologists who were blinded to the clinical-pathological data. Data were analysed using Kruskal-Wallis test and, for pair-wise comparisons, Mann-Whitney test with Bonferroni correction. RESULTS: All cystic epithelial linings stained for ß-catenin and survivin but there were differences in the pattern and intensity of staining among KCOT types. Sporadic primary KCOT showed weaker staining for ß-catenin (P=0.0003) and survivin (P<0.0048) that was restricted to the basal and para-basal layers only, compared to sporadic recurrent and NBCCS-associated KCOT, which showed expression throughout all epithelial layers. There were no differences in ß-catenin expression among recurrent and NBCCS-associated KCOT, whereas the intensity of survivin staining was higher in NBCCS-KCOT (P=0.0003). Nuclear staining for ß-catenin was found exclusively in recurrent (5/9 cases) and NBCCS-associated (4/12 cases) KCOT. CONCLUSION: The data demonstrate ß-catenin delocalization and survivin over-expression in recurrent sporadic and NBCCS-associated KCOT suggesting that these pathways related to apoptotic inhibition have a role in KCOT growth and recurrence.

Phage-display library biopanning as a novel approach to identifying nematode vaccine antigens.

Infections with parasitic nematodes are of significant welfare and economic importance worldwide, and because of the emergence of anthelmintic resistance, this has lead to alternative methods of parasite control being required. Vaccination offers a feasible alternative control, and the majority of research has focused on the production of recombinant versions of native antigens previously identified as protective in vaccinated animals. Attempts at the production of protective recombinant subunit vaccines have been hindered, however, as these antigens have invariably failed to replicate the same level of protective immune response as seen with the native versions. It has been proposed that these failures are owing to the fact that the recombinant proteins do not contain the appropriate post-translational modifications to retain the protective capacity of the native molecules. In this review, we discuss a novel approach to vaccine antigen identification through the application of random peptide phage-display libraries and their use to identify peptide sequences that potentially mimic the structure(s) of antigenic epitopes. This area of research is still relatively novel with respect to parasites, and the current state of the art will be discussed here.

A calcium-activated apyrase from Teladorsagia circumcincta: an excretory/secretory antigen capable of modulating host immune responses?

A cDNA representing the gene Teladorsagia circumcincta apyrase-1 (Tci-apy-1) was isolated, by PCR, from a T. circumcincta fourth-stage larval (L4) cDNA library. The closest orthologue of this gene is a Ca(2+)-dependent apyrase from Ostertagia ostertagi, with 92% amino acid identity across all 339 residues. Tci-apy-1 is transcribed in a stage-specific manner, the transcript being predominant in L4, detectable in the adult cDNA, but absent from eggs and infective third-stage larvae (L3). The protein, Tci-APY-1, was detected by immunoblotting in extracts of L4 nematodes and was present in excretory/secretory products from the same developmental stage. A recombinant version of Tci-APY-1 was expressed in bacteria as an active enzyme that hydrolysed nucleoside triphosphate substrates with a preference of ATP over other nucleoside triphosphates. Recombinant Tci-APY-1 hydrolysed ATP and ADP but not AMP. Apyrase activity was divalent cation-dependent, with no hydrolysis in the presence of Mg(2+), but activation in the presence of Ca(2+). Recombinant Tci-APY-1 was bound by IgG present in serum and both IgG and IgA present in abomasal mucus from trickle-infected, immune sheep but not in material derived from lambs exposed to a single infection. The potential immunomodulatory roles of this Tci-APY-1 are discussed in relation to purinergic signalling.

A macrophage migration inhibitory factor-like tautomerase from Teladorsagia circumcincta (Nematoda: Strongylida).

A macrophage migration inhibitory factor (MIF)-like molecule, Tci-MIF-1, was isolated from Teladorsagia circumcincta and subjected to detailed characterization. A cDNA representing Tci-mif-1 was isolated following its identification in third-stage larvae (L3)-enriched cDNA population. Sequencing of the cDNA indicated a 348-bp open reading frame (ORF) with the closest orthologue being a MIF derived from the human hookworm Ancylostoma ceylanicum. Messenger RNA (mRNA) representing the Tci-MIF-1 transcript was detected in eggs, L3 and adult stages of T. circumcincta. The transcript was also present, but to a lesser extent in fourth-stage larvae (L4). Detection of Tci-MIF-1 protein in T. circumcincta developmental stages reflected the transcript levels identified by reverse transcriptase-PCR. Using immunohistochemistry, the Tci-MIF-1 protein was shown to have a diffuse distribution in L3 tissue, and in L4 and adult stages, the protein was localized to the nematode gut. A recombinant version of Tci-MIF-1 was produced, and enzymic assays indicated that this recombinant protein and a somatic extract of L3 possessed dopachrome tautomerase activity as has been observed previously in other MIF-like molecules. Neither native, purified Tci-MIF nor recombinant Tci-MIF-1 dramatically influenced the in vitro migration of sheep monocytes.

MMP-13 expression in keratocyst odontogenic tumour associated with NBCCS and sporadic keratocysts.

OBJECTIVE: To investigate the matrix metalloproteinase (MMP)-13 expression in associated and non-nevoid basal cell carcinoma syndrome (NBCCS) Odontogenic Keratocysts (OCKs) in order to contribute to a better understanding of the differences in the growth pattern between them. MATERIALS AND METHODS: Thirty-nine paraffin-embedded blocks of OCKs, 26 sporadic OCKs and 11 NBCCS-associated KCOTs were studied by immunohistochemistry to evaluate MMP-13 expression both in epithelial and stromal layers. A semi-quantitative scale was used to evaluate immunostaining. Obtained data were compared between the two groups, using Fischer's exact test and the chi-square test. RESULTS: Only 13 of 26 sporadic OCKs showed a positive immunostaining, whilst 11 KCOTs resulted in positive labelling for MMP-13 expression. Moreover, syndromic cysts displayed a more intense and diffuse MMP-13 labelling of the stromal tissue. Instead, in non-syndromic forms, the staining pattern of MMP-13 in stromal tissue was completely absent. Fisher's exact test showed a statistically significant greater prevalence of KCOTs-immunolabelled cysts with respect to sporadic OCKs. CONCLUSIONS: Results from this study point out that the biological behaviour of these cysts could be related not only to the epithelial layer but also to stromal tissue in that... MMP-13 overexpression in stromal tissue of NBCCS-associated KCOTs could clarify the higher aggressiveness of these cysts.

Differential activation of NF-kappaB and gene expression in oral epithelial cells by periodontal pathogens.

To investigate the molecular effects of the periodontopathogens Fusobacterium nucleatum (FN) and Porphyromonas gingivalis (PG) on the oral epithelium, the H400 oral epithelial cell line was cultured in the presence of non-viable bacteria. Following confirmation of the presence of transcripts for the bacterial pattern recognition receptors in H400 cells, Toll-like receptors -2, -4 and -9, and components of the NF-kappaB signalling pathway, immunocytochemical analyses were performed showing that NF-kappaB was activated within 1 h of exposure to both periodontopathogens. A significantly greater number of NF-kappaB nuclear translocations were apparent following H400 cell exposure to FN as compared with PG. Gene expression analyses indicated that transcripts known to be regulated by the NF-kappaB pathway, including cytokines/chemokines TNF-alpha, IL-1beta, IL-8, MCP-1/CCL2 and GM-CSF, were up-regulated following 4 and 24 h of exposure to both periodontopathogens. In addition, H400 periodontopathogen exposure resulted in differential regulation of transcripts for several cytokeratin gene family members. Consistent with the immunocytochemical data, microarray results indicated that FN induced a greater number of gene expression changes than PG following 24 h of exposure, 609 and 409 genes, respectively. Ninety-one genes were commonly differentially expressed by both periodontopathogens and represented biological processes commonly associated with periodontitis. Gene expression analyses by reserve transcriptase-polymerase chain reaction (RT-PCR) of molecules identified from the microarray data sets, including Heme oxygenase-1, lysyl oxidase, SOD2, CCL20 and calprotectin components, confirmed their differential expression profiles induced by the two periodontopathogens. FN and PG have clearly different molecular effects on oral epithelial cells, potentially highlighting the importance of the composition of the plaque biofilm in periodontitis pathogenesis.

Hyperactivity and reactivity of peripheral blood neutrophils in chronic periodontitis.

Some evidence exists that peripheral neutrophils from patients with chronic periodontitis generate higher levels of reactive oxygen species (ROS) after Fcgamma-receptor stimulation than those from healthy controls. We hypothesized that peripheral neutrophils in periodontitis also show both hyper-reactivity to plaque organisms and hyperactivity in terms of baseline, unstimulated generation and release of ROS. Peripheral neutrophils from chronic periodontitis patients and age/sex/smoking-matched healthy controls (18 pairs) were assayed for total ROS generation and extracellular ROS release, with and without stimulation (Fcgamma-receptor and Fusobacterium nucleatum), using luminol and isoluminol chemiluminescence. Assays were performed with and without priming with Escherichia coli lipopolysaccharide (LPS) and granulocyte-macrophage colony-stimulating factor (GM-CSF). Phox gene expression (p22, p47, p67, gp91) was investigated using reverse transcription-polymerase chain reaction (RT-PCR). Neutrophils from patients produced higher mean levels of ROS in all assays. Total generation and extracellular release of ROS by patients' cells were significantly greater than those from controls after FcgammaR-stimulation, with (P = 0.023) and without (P < or = 0.023) priming with GM-CSF. Differences in unstimulated total ROS generation were not significant. By contrast, patients' cells demonstrated greater baseline, extracellular ROS release than those from controls (P = 0.004). This difference was maintained after priming with LPS (P = 0.028) but not GM-CSF (P = 0.217). Phox gene expression was similar in patient and control cells at baseline and stimulation with F. nucleatum (3 h) consistently reduced gp91(PHOX) transcripts. Our data demonstrate that peripheral neutrophils from periodontitis patients exhibit hyper-reactivity following stimulation (Fcgamma-receptor and F. nucleatum) and hyperactivity in terms of excess ROS release in the absence of exogenous stimulation. This hyperactive/-reactive neutrophil phenotype is not associated with elevated phox gene expression.

TNF-alpha SNP haplotype frequencies in equidae.

Tumour necrosis factor alpha (TNF-alpha) is a pro-inflammatory cytokine that plays a crucial role in the regulation of inflammatory and immune responses. In all vertebrate species the genes encoding TNF-alpha are located within the major histocompatability complex. In the horse TNF-alpha has been ascribed a role in a variety of important disease processes. Previously two single nucleotide polymorphisms (SNPs) have been reported within the 5' un-translated region of the equine TNF-alpha gene. We have examined the equine TNF-alpha promoter region further for additional SNPs by analysing DNA from 131 horses (Equus caballus), 19 donkeys (E. asinus), 2 Grant's zebras (E. burchellii boehmi) and one onager (E. hemionus). Two further SNPs were identified at nucleotide positions 24 (T/G) and 452 (T/C) relative to the first nucleotide of the 522 bp polymerase chain reaction product. A sequence variant at position 51 was observed between equidae. SNaPSHOT genotyping assays for these and the two previously reported SNPs were performed on 457 horses comprising seven different breeds and 23 donkeys to determine the gene frequencies. SNP frequencies varied considerably between different horse breeds and also between the equine species. In total, nine different TNF-alpha promoter SNP haplotypes and their frequencies were established amongst the various equidae examined, with some haplotypes being found only in horses and others only in donkeys or zebras. The haplotype frequencies observed varied greatly between different horse breeds. Such haplotypes may relate to levels of TNF-alpha production and disease susceptibility and further investigation is required to identify associations between particular haplotypes and altered risk of disease.

Platelet-derived growth factor (PDGF) isoform and PDGF receptor expression in drug-induced gingival overgrowth and hereditary gingival fibrosis.

OBJECTIVE: To investigate possible associations between platelet-derived growth factor (PDGF), PDGF receptor expression and macrophages in drug-induced and hereditary gingival overgrowth. MATERIALS AND METHODS: Tissues from patients with drug-induced gingival overgrowth (DIGO) (n = 10) and hereditary gingival fibrosis (n = 10) were studied and compared with 'control' gingiva (n = 10). Expression of PDGF and its alpha and beta receptors was investigated immunohistochemically and by RT-PCR. Macrophages were identified by immunostaining for CD68. RESULTS: PDGF isoforms and receptors were detected in most cells within all specimens. There were no differences in the numbers of macrophages, or fibroblasts expressing PDGF or receptors, between groups. The level of PDGF expression by fibroblasts, determined by absorbance measurements, was similar between groups for PDGF A. Significantly lower levels of total PDGF and the receptors were detected in drug-induced overgrowth compared to those in hereditary fibrosis (P < 0.004) and control specimens (P < 0.034). All specimens expressed mRNA for PDGF A, PDGF B and alpha and beta receptors. CONCLUSIONS: These data do not support a pivotal role for macrophage-derived PDGF B in the pathogenesis of DIGO. They suggest that fibroblasts in drug-induced lesions have a lowered capacity to produce, and respond to, PDGF, a property not shared by fibroblasts associated with hereditary fibrosis.

Cytokine responses to Cyathostominae larvae in the equine large intestinal wall.

To investigate cytokine responses in cyathostomin infection, we quantified mucosal interleukin-4 (IL-4), interleukin-10 (IL-10), tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma by reverse transcriptase-competitive polymerase chain reaction. The analysis was performed on large intestinal wall samples obtained from six anatomical sites spanning the caecum and colon of 17 naturally exposed horses. The numbers of developing larvae (DL) and early third stage larvae (EL3) were ascertained using transmural illumination and pepsin digestion techniques, respectively. Levels of each cytokine transcript were correlated with local intestinal wall burdens of Cyathostominae larvae. IL-4 and IL-10 levels showed significant correlations with EL3 and DL burdens at several sites. No significant correlations were observed with IFNgamma. A pro-inflammatory response, typified by detection of TNFalpha transcript, was observed at a few sites in some horses with inflammatory enteropathy associated with emerging or emerged larvae. However, this cytokine was measured at an insufficient number of sites to enable statistical analysis. Levels of IL-4, IL-10 and IFNgamma transcript were compared between two groups: one group consisting of horses with low to high mucosal burdens (Group A) and the other, of horses with negative/negligible mucosal burdens (Group B). Significant differences in IL-4 (P<0.001) and IL-10 (P<0.001) transcript levels were observed between the groups, with higher levels observed in Group A. No significant differences in IFNgamma were observed. Taken together, these results indicate that Th2 responses predominate in mucosal Cyathostominae infection prior to larval reactivation.

Local and systemic total antioxidant capacity in periodontitis and health.

BACKGROUND: The involvement of reactive oxygen species (ROS) in periodontal pathology is unclear but will be modulated by in vivo antioxidant defence systems. The aim of this cross-sectional study was to determine both local (saliva and gingival crevicular fluid (GCF) and peripheral (plasma and serum) antioxidant capacity in periodontal health and disease. MATERIALS AND METHODS: Twenty non-smoking volunteers with chronic periodontitis were sampled together with twenty age- and sex-matched, non-smoking controls. After overnight fasting, saliva (whole unstimulated and stimulated) and blood were collected. Total antioxidant capacity (TAOC) was determined using a previously reported enhanced chemiluminescence method. RESULTS: GCF antioxidant concentration was significantly lower (p<0.001) in periodontitis subjects compared to healthy controls. Although mean levels of peripheral and salivary TAOC were also lower in periodontitis the difference was only significant for plasma (p<0.05). Healthy subjects' GCF antioxidant concentration was significantly greater than paired serum or plasma (p<0.001). Data stratified for gender did not alter the findings and a male bias was revealed in all clinical samples except GCF. CONCLUSIONS: These findings suggest that the antioxidant capacity of GCF is both qualitatively and quantitatively distinct from that of saliva, plasma and serum. Whether changes in the GCF compartment in periodontitis reflect predisposition to or the results of ROS-mediated damage remains unclear. Reduced plasma total antioxidant defence could result from low-grade systemic inflammation induced by the host response to periodontal bacteria, or may be an innate feature of periodontitis patients.

Salivary gland expression of transforming growth factor beta isoforms in Sjogren's syndrome and benign lymphoepithelial lesions.

AIM: Transforming growth factor beta (TGF-beta) is involved in the control of autoimmune reactions, cell proliferation, and the accumulation of lymphocytes within organs. The aim of this study was to determine the expression of TGF-beta in salivary glands from patients with primary Sjogren's syndrome (SS) and benign lymphoepithelial lesions (BLEL) with emphasis on ductal epithelium. METHODS: Immunoperoxidase staining for TGF-beta isoforms and Ki67 antigen was performed on formalin fixed sections of labial glands from patients with primary SS (n = 15) and controls (n = 5) and parotid glands reported as BLEL (n = 5) or normal (n = 5). Ductal expression of TGF-beta was quantified by absorbance measurements using image analysis. The specificity of staining was confirmed by peptide blocking studies. RESULTS: All TGF-beta isoforms were detected within the cytoplasm of most lymphocytes, endothelial cells, and ducts in all specimens. Acinar expression was variable and weaker than that seen in ducts. Absorbance measurements revealed that the expression of all isoforms was greater in ducts within primary SS glands than in control glands. Ductal expression in control parotid glands was greater than that seen in BLEL glands, irrespective of the presence of adjacent lymphoid infiltrates. Comparisons between control specimens showed that ductal expression of all isoforms was highest in parotid glands, whereas no differences were detected between primary SS and BLEL glands. Ki67 positive lymphocytes and duct cells were mainly restricted to pathological specimens, with BLEL glands containing larger populations of positive cells than primary SS glands. CONCLUSION: These results demonstrate complex and variable changes in ductal expression of TGF-beta in primary SS and BLEL, which may be important in the control of lymphoid infiltration and the proliferation of lymphocytes and ductal epithelium.

Effects of clinically relevant alumina ceramic wear particles on TNF-alpha production by human peripheral blood mononuclear phagocytes.

The recent introduction of microseparation of the components of ceramic-on-ceramic hip prostheses during hip simulations has produced clinically relevant wear rates, wear patterns and wear particles. This provided an opportunity to determine the response of primary human peripheral blood mononuclear cells to clinically relevant alumina ceramic wear particles in vitro. Alumina ceramic wear particles were generated in a hip joint simulator under microseparation conditions. The particles showed a bi-modal size distribution with nanometer sized (5-20nm) and larger particles (0.2->10 micrometer). The particles were cultured with human peripheral blood mononuclear cells obtained from six different donors at particle volume to cell number ratios of 1, 10, 100 and 500 micrometer(3). After 24h incubation the viability of the cells and the levels of TNF-alpha were determined. The response to the microseparation wear particles was compared to that of commercially available alumina powder with a uniform morphology and mean size of 0.5 micrometer. All six Donors PBMNC produced significantly elevated levels of TNF-alpha when stimulated with 100 micrometer(3) of the alumina powder per cell. Volumetric concentrations of 10 and 1.0 micrometer(3) per cell failed to stimulate a significant response by the cells from any of the six donors. Three of the six Donors PBMNC secreted significantly elevated levels of TNF-alpha when stimulated with 100 micrometer(3) of the microseparation wear particles, whereas the other three failed to respond to the wear debris at this concentration. All of the Donors PBMNC produced significantly elevated levels of TNF-alpha when stimulated with 500 micrometer(3) of the microseparation wear particles per cell. Thus, a greater volume of the microseparation wear particles was required to activate the PBMNC than the alumina powder. This was probably due to the microseparation wear particles having fewer particles in the critical size range (0.1-1 micrometer) for macrophage activation compared to the alumina powder. It can be concluded that alumina ceramic wear particles generated under microseparation conditions are capable of inducing osteolytic cytokine production by human mononuclear phagocytes. However, the volumetric concentration of the particles needed to generate this response is extremely high and given the low wear rates (<4mm(3) per million cycles) of ceramic-on-ceramic bearings, even under severe microseparation conditions, it is unlikely that this concentration threshold will be achieved in vivo.

Ability of structurally diverse natural products and synthetic chemicals to induce gene expression mediated by estrogen receptors from various species.

The ability of 14 structurally diverse estrogenic compounds to induce reporter gene expression mediated by estrogen receptors (ERs) from different species was examined. MCF-7 cells were transiently transfected with a Gal4-regulated luciferase reporter gene (17m5-G-Luc) and Gal4-ER chimeric receptors containing the D, E and F domains of the human alpha (Gal4-hERalphadef), mouse alpha (Gal4-mERalphadef), mouse beta (Gal4-mERbetadef), chicken (Gal4-cERalphadef), green anole (Gal4-aERalphadef), Xenopus (Gal4-xERdef) or rainbow trout alpha ERs (Gal4-rtERalphadef). The efficacy of 17beta-estradiol (E2) in inducing reporter gene expression was similar among the different constructs overall, with EC(50) values ranging from 0.05 to 0.7nM. However, Gal4-rtERalphadef had an EC(50) value at 37 degrees C of 28nM, though at 20 degrees C an EC(50) value of 1nM was observed. Despite a similar response to E2 treatment among the ERs, many differences were observed in the magnitude of the response to other structurally diverse chemicals. For example, coumestrol induced Gal4-mERbetadef- and Gal4-aERdef-mediated reporter gene expression 164- and 8-fold greater, respectively, than mediated with the other Gal4-ERs. As well, in contrast to results with other Gal4-ERs, alpha-zearalenol consistently induced Gal4-rtERalphadef-mediated reporter gene activity at lower concentrations than did E2. Overall, the results demonstrate that selected estrogenic compounds exhibit a differential ability to induce reporter gene activity mediated by ERs from different vertebrate species. These data also highlight the importance of incubation temperature when examining rtERalpha-mediated activity.