Pathways Linking Oral Bacteria, Nitric Oxide Metabolism, and Health.

Nitrate-reducing oral bacteria have gained a lot of interest due to their involvement in nitric oxide (NO) synthesis and its important cardiometabolic outcomes. Consortia of nitrate-metabolizing oral bacteria associated with cardiometabolic health and cognitive function have been recently identified. Longitudinal studies and clinical trials have shown that chronic mouthwash use is associated with increased blood pressure and increased risk for prediabetes/diabetes and hypertension. Concurrently, recent studies are beginning to shed some light on the complexity of nitrate reduction pathways of oral bacteria, such as dissimilatory nitrate reduction to ammonium (DNRA), which converts nitrite into ammonium, and denitrification, which converts nitrite to NO, nitrous oxide, and dinitrogen. These pathways can affect the composition and metabolism of the oral microbiome; consequently, salivary nitrate and nitrite metabolism have been proposed as targets for probiotics and oral health. These pathways could also affect systemic NO levels because NO generated through denitrification can be oxidized back to nitrite in the saliva, thus facilitating flux along the NO3--NO2--NO pathway, while DNRA converts nitrite to ammonium, leading to reduced NO. It is, therefore, important to understand which pathway predominates under different oral environmental conditions, since the clinical consequences could be different for oral and systemic health. Recent studies show that oral hygiene measures such as tongue cleaning and dietary nitrate are likely to favor denitrifying bacteria such as Neisseria, which are linked with better cardiometabolic health. A vast body of literature demonstrates that redox potential, carbon-to-nitrate ratio, and nitrate-to-nitrite ratio are key environmental drivers of the competing denitrification and DNRA pathways in various natural and artificial ecosystems. Based on this information, a novel behavioral and microbial model for nitric oxide metabolism and health is proposed, which links lifestyle factors with oral and systemic health through NO metabolism.

Biomass fuel production from cellulosic sludge through biodrying: Aeration strategies, quality of end-products, gaseous emissions and techno-economic assessment.

This study assesses the technological, environmental and economic feasibility of biodrying to valorise cellulosic sludge as a renewable energy source. Specifically, three different aeration strategies were compared in terms of biodrying performance, energetic consumption, gaseous emissions, quality of end-products and techno-economic analysis. These strategies were based on different combinations of convective drying with biogenic heat produced. Two innovative biodrying performance indicators (Energetic Biodrying Index and Biodrying Performance Index) were proposed to better assess the initial and operational conditions that favour the maximum energy process efficiency and the highest end-product quality. The end-products obtained consistently presented moisture contents below 40% and lower heating values above 9.4 MJ·kg-1. However, the best values achieved were 32.6% and 10.4 MJ·kg-1 for moisture content and lower heating value, respectively. Low N2O and CH4 emissions confirmed the effective aeration of all three strategies carried out, while NH4 and tVOCs were related either to temperature or biological phenomena. A techno-economic analysis proved the economic viability and attractiveness of the biodrying technology for cellulosic sludge in all the strategies applied.

Ammonium acetate as a novel buffer for highly selective robust urinary HPLC-ICP-MS arsenic speciation methodology.

Ammonium acetate is employed in order to develop a novel HPLC-ICP-MS arsenic speciation methodology applicable to six arsenic species, i.e, AC, AB, AsIII, AsV, DMA and MMA. The most predominant species in the toxicological field are covered in a 30-min chromatogram with reproducible and repeatability peak area ratio. Moreover, typical problems from traditional methods are sorted out by using a robust, high-selective and 75ArCl+ interference-free methodology. Chromatographic and detector optimization ensures low LOQs for each species with acceptable precision and accuracy values obtained using four urinary arsenic speciation PTS enabling to be useful for sub ng mL-1 arsenic exposure assessments.

CalcPEFDairy: A Product Environmental Footprint compliant tool for a tailored assessment of raw milk and dairy products.

A compliant tool (CalcPEFDairy) to determine the Product Environmental Footprint (PEF) of Dairy products has been developed following the Product Environmental Footprint Category Rules (PEFCR) v.6.3 guidance and the 2018 approved PEFCR for Dairy products. CalcPEFDairy is a new tool that simplifies and reduces the work for LCA practitioners when implementing the PEFCR for Dairy products. On contrary to traditional LCA software, CalcPEFDairy includes all the emission models needed to calculate farm and crop cultivation direct emissions and it also implements the specific calculation formulas stated in the PEFCR such as the Circular Footprint and Data Quality Requirement formulas. Moreover, the PEF compliant datasets provided by the Life Cycle Data Network are incorporated in the tool as source of secondary data. To demonstrate the accuracy of the tool a traditional dairy farm in Catalonia (Northwest of Spain) was assessed and the results compared with the European representative PEF compliant datasets for the production of raw milk, cheese and yoghurt. In addition to the environmental profile, CalcPEFDairy has determined the case study's environmental single score (ESS) for the production of raw milk (1.0 × 10-4) cheese (9.7 × 10-6) and yoghurt (1.4 × 10-5); these ESS results are within the range of the ESS obtained from the analysed EF-datasets. The data sets' average ESS for raw milk is 9.9 × 10-5 ± 1.1 × 10-5, while for cheese and yoghurt are 1.5 × 10-5 ± 3.1 × 10-6 and 1.9 × 10-5 ± 3.4 × 10-6 respectively. A 78% of the raw milk production ESS is attributed to the dairy farm activities while, the raw milk production stage affects in a 87.4% and 80.1% to the ESS for cheese and yoghurt respectively.

Health assessment of Conolophus subcristatus, Conolophus pallidus, and C. subcristatus X Amblyrhynchus cristatus hybrid (Galápagos land iguanas).

The land iguanas, Conolophus pallidus and Conolophus subcristatu are large and charismatic lizards endemic to the Galápagos archipelago, but little information exists on their normal health parameters. The former is restricted to Santa Fe island, while C. subcristatus inhabits the islands of the central and western region of the archipelago. Both species are classified as vulnerable by the IUCN Red List of Threatened Species. As part of a population health assessment authorized by the Galápagos National Park, wild adult iguanas from three islands (North Seymour, South Plazas, and Santa Fe) were captured in July 2018. Data from a single C. subcristatus X Amblyrhynchus cristatus hybrid captured on South Plazas is also included. We analyzed blood samples drawn from 52 healthy wild adult land iguanas captured on three islands. An iSTAT portable blood analyzer was used to obtain values for pH, lactate, pO2, pCO2, HCO3-, sO2%, hematocrit, packed cell volume (PCV), hemoglobin Na, K, iCa, and glucose. Standard laboratory hematology techniques were employed for PCV determination; resulting values were also compared to the hematocrit values generated by the iSTAT. Body temperature, heart rate, respiratory rate, and body measurements were also recorded and compared to previously published data for the marine iguana (Amblyrhynchus cristatus), which shares a common ancestor with the land iguana. The data reported here provide preliminary baseline values that may be useful in comparisons between captive and wild populations, between wild populations, and in detecting changes in health status among Galápagos land iguanas affected by anthropogenic threats, climate change, or natural disturbances.

Increased Diameters of the Internal Cerebral Veins and the Basal Veins of Rosenthal Are Associated with White Matter Hyperintensity Volume.

BACKGROUND AND PURPOSE: White matter hyperintensities on T2-weighted MR imaging are typical in older adults and have been linked to several poor health outcomes, including cognitive impairment and Alzheimer disease. The presence and severity of white matter hyperintensities have traditionally been attributed to occlusive arteriopathy, but recent evidence also implicates deep medullary venule collagenosis and associated vasogenic edema. Historically, postmortem analyses have been the sole way to analyze cerebral veins, but SWI can be now used to examine cortical veins in vivo. The aim of the current study was to determine whether there is an association between the diameters of the large draining cerebral veins/sinuses and white matter hyperintensity volume. MATERIALS AND METHODS: T2-weighted FLAIR and SWI were performed in 682 older adults without dementia (mean age, 73.9 ± 5.9 years; 59.1% women). Total and regional white matter hyperintensity volume was derived. We measured the diameters of 5 regions of the cerebral venous draining system: internal cerebral veins, basal veins of Rosenthal, superior sagittal sinus, vein of Galen, and straight sinus terminus. RESULTS: Increased diameter of the internal cerebral veins was associated with greater total white matter hyperintensity volume (ß = 0.09, P = .02) and regionally in the parietal (ß = 0.10, P = .006), frontal (ß = 0.09, P = .02), and temporal (ß = 0.09, P = .02) lobes. Increased diameter of the basal veins of Rosenthal was associated with greater total (ß = 0.10, P = .01), frontal (ß = 0.11, P = .003), and temporal (ß = 0.09, P = .02) white matter hyperintensity volume. CONCLUSIONS: Our results suggest that the caliber of the internal cerebral veins and of the basal veins of Rosenthal relates to regional white matter disease.

Methods of body temperature assessment in Conolophus subcristatus, Conolophus pallidus (Galápagos land iguanas), and Amblyrhynchus cristatus X C. subcristatus hybrid.

Since cardiovascular, respiratory, and metabolic systems of reptiles are affected by temperature, accurate measurements are of great importance in both captive husbandry and research. Ectothermic animals generally have core body temperatures close to ambient temperature but can differ from the immediate environment if they are using sunlight to thermoregulate. Many zoological facilities and exotic pet caregivers have begun using infrared temperature guns to assess ambient temperatures of reptile enclosures but there are currently few studies assessing the efficacy of these devices for measuring the body temperatures of reptiles. Conolophus subcristatus, Conolophus pallidus (Galápagos land iguanas), and Amblyrhynchus cristatus X C. subcristatus hybrid are robust land iguanas endemic to the Galápagos archipelago. By comparing the infrared body temperature measurements of land iguanas against virtual simultaneous collection of cloacal temperatures obtained using a thermocouple thermometer, we sought to assess the efficacy of this non-invasive method. We found that internal body temperature can be predicted with a high level of accuracy from three external body temperature sites, providing a good non-invasive method that avoids the capture of animals.

Hydrodynamics of high solids anaerobic reactor: Characterization of solid segregation and liquid mixing pattern in a pilot plant VALORGA facility under different reactor geometry.

One of the main problems of dry anaerobic digestion plants treating urban solid waste is the loss of useful volume by the sedimentation of solids (inerts) into the bottom of the digester, or by accumulation of floating materials in its upper part. This entails a periodic cost of emptying and cleaning the digesters, a decrease in biogas production and complications in maintenance. Usually the sedimentation is a consequence of the heterogeneity of waste that, in addition to organic matter, drags particles of high density that end up obstructing the digesters. To reduce this bottleneck, URBASER has designed a new configuration of VALORGA reactor. That is, the VALORGA central wall has been removed and an inclined bottom has been added. To test the sedimentability and the overall performance of both configurations (current and new design), hydrodynamic tests have been carried out in a pilot digester (digester of 95 m3 capacity). To simulate the liquid phase and the solid phase of the reactor, lithium tracers and tags of different densities with RFID (radio frequency identification reader) have been used respectively. The results of the study showed an improvement in the performance of the new reactor design at pilot level.

Analysis of MSW full-scale facilities based on anaerobic digestion and/or composting using respiration indices as performance indicators.

The Landfill Directive (1999/31/EC) forces European States to reduce the amount of biodegradable municipal waste landfilled to 35% of 1995 levels. Mechanical-Biological Treatment (MBT) plants are the main alternative to waste incineration and landfilling. In this work, the waste treatment efficiency of six full-scale MBT facilities has been analysed using respiration indices (Dynamic Respiration Index and Cumulative Oxygen Consumption) to monitor plant performance. MBTs relying on anaerobic digestion plus composting achieved a high grade of stability on final compost (0.24±0.09mgO2g-1DMh-1 and 20±9mgO2g-1DM for dynamic respiration and cumulative consumption, respectively). On the contrary, MBTs relying only on composting showed a poor performance (1.3±0.2mgO2g-1DMh-1 and 104±18mgO2g-1DM for dynamic respiration and cumulative consumption, respectively). These results highlight the usefulness of respirometric balances to assess the performance of MBT full-scale plants.

[Validation of an in-house method for the determination of zinc in serum: Meeting the requirements of ISO 17025]. / Propuesta de un procedimiento de validación de un método para la determinación de cinc sérico: cumplimiento de los requisitos de la ISO 17025.

OBJECTIVE: The aim of this report is to propose a scheme for validation of an analytical technique according to ISO 17025. MATERIAL AND METHODS: According to ISO 17025, the fundamental parameters tested were: selectivity, calibration model, precision, accuracy, uncertainty of measurement, and analytical interference. RESULTS: A protocol has been developed that has been applied successfully to quantify zinc in serum by atomic absorption spectrometry. CONCLUSION: It is demonstrated that our method is selective, linear, accurate, and precise, making it suitable for use in routine diagnostics.

Blockade of MUC1 expression by glycerol guaiacolate inhibits proliferation of human breast cancer cells.

We sought to determine whether administration of glycerol guaiacolate at an optimal biological dose inhibits human breast cancer cell growth. Human breast cancer MCF-7 and ZR-75-1 cells were treated with glycerol guaiacolate and the therapeutic efficacy and biological activity of this drug was investigated on breast cancer cell growth. MCF-7 cells were injected into the mammary fat pad of overectamized female athymic nude mice. Ten days later, animals were treated with daily intraperitoneal injections of glycerol guaiacolate for six weeks. Tumor size and volume was monitored and immunohistochemistry analysis on MUC1, p21 and ki-67 was performed. Glycerol guaiacolate decreased breast cancer cell growth in a dose-dependent manner, decreased cell migration, and caused G1 cell cycle arrest. Our results demonstrate that glycerol guaiacolate inhibits MUC1 protein and mRNA expression levels and significantly increased p21 expression in human breast cancer cells as well as induced PARP cleavage. Similarly, glycerol guaiacolate inhibited breast tumor growth in vivo as well as enhanced p21 expression and decreased breast tumor cell proliferation (ki-67 expression). Collectively, our results demonstrate that glycerol guaiacolate decreased MUC1 expression and enhanced cell growth inhibition by inducing p21 expression in breast cancer cells. These findings suggest that glycerol guaiacolate may provide a novel and effective approach for the treatment of human breast cancer.

Tissue factor-bearing microparticles derived from tumor cells: impact on coagulation activation.

BACKGROUND: Tissue factor (TF)-bearing microparticles (MP) from different origins are thought to be involved in the pathogenesis of cancer-associated thrombosis. However, the role of circulating tumor cell-derived TF is not well understood. METHODS: TF antigen and activity were measured in MP generated in vitro from human TF-expressing cancer cells by ELISA and clotting or thrombin generation assays, respectively. TF antigen and activity were also measured in vivo in cell-free plasmas from mice previously injected with in vitro-generated MP or in cell-free plasmas from nude mice bearing orthotopically injected human cancer cells. RESULTS: Tumor cell-derived MP (TMP) exhibited strong TF-dependent procoagulant activity (PCA) in vitro and in vivo. Injection of TMP into mice was associated with acute thrombocytopenia and signs of shock, which were prevented by prior heparinization. Human TF antigen and activity could be detected in mouse cell-free plasmas up to 30 min after TMP injections. Human TF was detected in the spleen of injected mice and its clearance from circulation was delayed in splenectomized mice, suggesting the involvement of the spleen in the rapid clearance of circulating MP in vivo. Detectable levels of TF-dependent PCA and thrombin-antithrombin complex were found in cell-free plasmas from mice growing pancreatic human tumors, suggesting that circulating tumor-derived TF causes coagulation activation in vivo. CONCLUSIONS: MP derived from certain cancer cells exhibit TF-dependent PCA both in vitro and in vivo. These results provide new information about the specific contribution of tumor-derived MP to the hypercoagulable state observed in cancer.

Impaired cytokine production and suppressed lymphocyte proliferation activity in HCV-infected cocaine and heroin ("speedball") users.

HCV-infected "speedball" users (n = 30) were selected from an original cohort of 400 intravenous drug users for cytokine analysis. Cytokine concentrations (TNF-alpha, IL-1beta, IL-6, IFN-gamma, IL-2, IL-4, IL-10 and IL-12) were determined in plasma and peripheral blood mononuclear cells (PBMC) cultures derived ex vivo from these patients. In addition, lymphocyte proliferation was measured in 49 HCV-positive "speedball" users. TNF-alpha, IL-6, IFN-gamma, IL-2, IL-4, IL-10, IL-12 cytokines and not IL-1beta were significantly increased in plasma from HCV-positive "speedball" users compared with healthy controls. Except for IL-10, all other cytokines measured were augmented in phytohemagglutinin-stimulated PBMC cultures from HCV-positive "speedball" users. Likewise, overproduction of cytokines TNF-alpha, IL-1beta, IL-6 and IFN-gamma, was consistently detected when PBMC cultures from HCV-positive "speedball" users were stimulated with a biological response modifier. However, HCV-infected "speedball" users showed significant reduction in lymphoproliferative activity. Compared with healthy subjects, there was a consistent overproduction of both TH1 and TH2 type cytokines in the plasma and PBMC's of HCV-infected "speedball" users. Furthermore, there was a persistent reduction of lymphoproliferative activity in this group. These immunologic abnormalities, coupled with the range of response between the two TH-types in HCV-infected "speedball" users, suggest impairment in the regulatory mechanism of the TH1-TH2 system.

[Study of immutable variables determining rHuEPO dose requirements on hemodialysis patients]. / Estudio de causas no modificables de pobre respuesta al tratamiento con eritropoyetina en pacientes en hemodiálisis.

Patients receiving recombinant human erythropoietin (rHuEPO) therapy show wide variability in their responsiveness to the drug. Variables that affect rHuEPO dose requirements can be broadly divided into modificable and immutable characteristics. Most of the scientific research on rHuEPO hyporesponsiveness has focused on modificable variables (iron status, dialysis adequacy), while immutable variables such as gender, etiology of chronic renal failure (CRF) and age have been insufficiently explored. A cross sectional study was performed in order to evaluate if immutable patient characteristics determine rHuEPO dose requirements among 215 patients (52% males; mean age 66 +/- 14 years) on hemodialysis (HD) for more than twelve months. Data were collected at 10 hemodialysis units in Aragon. Patients were divided into three groups according to their gender, their cause of CRF (diabetic nephropathy, vascular nephropathy, tubulointerstitial nephropathy and primary glomerulonephritis) and their age (younger than 60 years, from 60 to 75 years, older than 75 years). Despite a similar dose of rHuEPO, women had lower mean hemoglobin (11.1 +/- 1.5 versus 11.6 +/- 1.7 g/dl; p = 0.0258) than men. The greater hemoglobin in men than women may be attributed to greater serum albumin in men (3.5 +/- 0.3 versus 3.7 +/- 0.3 mg/dl; p = 0.0001). Requirements of rHuEPO were higher in the patients with etiology of primary glomerulonephritis compared with those with the other etiologies, even those with diabetic nephropathy (p = 0.0374). The rHuE-PO doses required to obtain similar hemoglobin levels were higher in patients younger than 60 years (p = 0.0249). We conclude that women, patients with primary glomerulonephritis as cause of CRF, and patients younger than 60 years showed the highest requirements of rHuEPO doses.

Autoantibodies to human alpha6 integrin in patients with oral pemphigoid.

Mucous membrane pemphigoid or cicatricial pemphigoid is a mucocutaneous blistering disease characterized by autoantibodies to different molecules in the basement membrane zone. Our objectives were to identify the target antigen recognized by sera from 20 untreated patients with pemphigoid disease limited to the oral cavity, and to determine the pathogenicity of autoantibodies in oral pemphigoid, with an organ culture model. We conducted indirect immunofluorescence, immunoblot, and immunoprecipitation assays, with accompanying absorption experiments, using normal human skin, conjunctiva and gingiva, bovine gingiva and a tumor cell line, which were reacted with sera from patients with oral pemphigoid, anti-alpha6 antibody, and control sera. Sera of oral pemphigoid patients selectively and specifically bound to human alpha6 integrin, a 120-kDa protein present in gingiva and the tumor cell line. Oral pemphigoid sera and anti-alpha6 antibody produced separation of epithelium from basement membrane (blister formation) of normal human buccal mucosa, after 48 hours, in organ culture.

Comparison between intravenous immunoglobulin and conventional immunosuppressive therapy regimens in patients with severe oral pemphigoid: effects on disease progression in patients nonresponsive to dapsone therapy.

CONTEXT: Mucous membrane pemphigoid has a wide clinical spectrum. The clinical context was to determine whether pemphigoid disease that initiates in the oral cavity progresses to involve other mucosae and to determine the influence of systemic therapy on such progression. OBJECTIVE: To determine the clinical outcomes and disease progression in patients with oral pemphigoid for whom dapsone therapy was impossible. DESIGN: Retrospective analysis of a cohort of 20 patients with immunopathologic-proven oral pemphigoid studied between September 1, 1994, and October 31, 2000. Twelve patients received conventional therapy that consisted of a combination of oral prednisone with an immunosuppressive agent. Eight patients in whom such therapy was contraindicated received intravenous immunoglobulin therapy. Patients were followed up for 33 to 62 months (mean follow-up, 47.5 months). SETTING: Patients were treated in an ambulatory tertiary medical care facility of a university-affiliated hospital. PATIENTS: The 20 patients had pemphigoid disease limited to the oral cavity only at the initial clinical presentation and when enrolled in the study. MAIN OUTCOME MEASURES: The following variables were compared between the 2 groups of patients: (1) duration of treatment, (2) frequency of relapses, (3) induction of remission, (4) adverse effects of therapy, (5) extra oral involvement, and (6) quality of life. RESULTS: Using the aforementioned factors, the group treated with intravenous immunoglobulin had statistically significant shorter treatment duration, fewer relapses, higher remission rate, fewer adverse effects, no extraoral involvement, and a better quality of life compared with the group who received conventional therapy. CONCLUSIONS: Intravenous immunoglobulin is a safe and effective modality to treat mucous membrane pemphigoid. It seems to be a good option for patients who cannot be treated with dapsone and in whom conventional therapy is contraindicated or results in the development of serious adverse effects. In patients with progressive mucous membrane pemphigoid, intravenous immunoglobulin therapy may arrest disease progression.

Pemphigus vulgaris: the role of IL-1 and IL-1 receptor antagonist in pathogenesis and effects of intravenous immunoglobulin on their production.

Intravenous immunoglobulin (IVIG) is increasingly being used for the treatment of autoimmune diseases. In the present report, the role of IVIG on in vivo and in vitro production of IL-1 and IL-1 receptor antagonist (Ra) was studied in patients with pemphigus vulgaris (PV). Serum samples from 20 untreated patients with active PV prior to initiation of systemic therapy, 20 patients receiving IVIG treatment, 20 patients in clinical remission after conventional therapy, and 20 normal human controls were studied to determine the serum levels of IL-1alpha, IL-1beta, and IL-1Ra. The in vitro production of these cytokines was measured in the culture supernatant of peripheral blood mononuclear cells (PBMC) from 10 PV patients immediately before and after IVIG therapy and from age and sex-matched 10 healthy donors simultaneously. Elevated levels of IL-1alpha and IL-1beta were detected (i) in the serum of untreated PV patients with active disease prior to systemic therapy and (ii) before IVIG infusions in patients receiving IVIG therapy. These increased levels are statistically significant when compared to the levels in healthy controls (P < 0.01). A marked reduction of IL-1alpha and IL-1beta was detected (i) in the serum of patients in prolonged clinical remission and (ii) immediately after IVIG infusion in those patients on IVIG therapy. Increased level of IL-1Ra was detected in PV patients in prolonged clinical remission and after IVIG infusion in those receiving IVIG therapy. These differences were statistically significant when compared to the levels in normal controls and to the levels in the sera of patients with active disease (P < 0.01) or just before the beginning of IVIG infusion (P < 0.01). Similar differences in the levels of IL-1alpha, IL-1beta, and IL-1Ra were found in the culture supernatant of PBMC isolated from the PV patients pre and post IVIG therapy. These observations suggests that, compared to normal controls, patients with active PV have reversed levels of IL-1alpha, IL-1beta, and IL-1Ra. IVIG therapy may down-regulate production of IL-1alpha and IL-1beta and enhance production of IL-1Ra, in vivo and in vitro. This might be one of the important mechanisms by which IVIG produces its early therapeutic effects in pemphigus vulgaris.

In vitro organ culture model for mucous membrane pemphigoid.

Mucous membrane pemphigoid (MMP), also known as cicatricial pemphigoid, is a rare vesiculobullous disease of mucosal tissues, which involves the oral, ocular, and other mucous membranes. We have studied a group of patients with histologically and immunopathologically proven pemphigoid disease involving predominantly the conjunctiva and oral mucosa in addition to other mucosae. The purpose of our study was to (i) demonstrate the specific binding of autoantibodies present in the sera of patients with MMP to normal human oral mucosa by indirect immunofluorescence (IIF) and (ii) to study the role of these autoantibodies in the pathogenesis of subepithelial blister formation using normal human buccal mucosa in organ culture. Serum and IgG fractions from MMP patients showed homogeneous smooth linear binding along the basement membrane zone (BMZ) of the normal buccal mucosa on IIF. Serum from pemphigus vulgaris patients showed intercellular or keratinocyte cell surface staining. BMZ separation developed at 48 h after incubation of normal human buccal mucosa in organ culture, with serum or IgG from patients with MMP but not after addition of normal human serum. Addition of pemphigus vulgaris serum to the in vitro culture of normal human buccal mucosa showed acantholysis. This preliminary report suggests that circulating autoantibodies may have an important role in the pathogenesis of MMP. This in vitro organ culture model will facilitate enhancing our understanding of various molecular events during the process of blister formation in MMP and in the study of other mucosal diseases.

Qualitative and quantitative documentation of the racing performance of 461 Thoroughbred racehorses after arthroscopic removal of dorsoproximal first phalanx osteochondral fractures (1986-1995).

The purpose of this study was to examine the longevity of postoperative careers and quality of performance of 461 Thoroughbred racehorses after arthroscopic removal of dorsoproximal first phalanx (P1) osteochondral fractures. Six hundred and 59 dorsoproximal P1 chip fractures were removed arthroscopically from 574 joints in 461 horses presented for lameness or decreased performance attributed to the chip fractures. Radiological and arthroscopic examination revealed an average of 1.43 fragment sites/horse, 1.15 fragment sites/joint and 1.25 affected joints/horse. Eighty-nine percent of the horses (411/461) raced after surgery and 82% (377/461) did so at the same or higher class. Fifty horses did not race after surgery. Sixty-eight percent of the horses raced in a Stake or Allowance race postoperatively. Data, previously undocumented, establishes that the quantity and quality of performance is not diminished after arthroscopic treatment of dorsoproximal P1 fragmentation. Surgical removal of chip fractures is a means of preserving the economic value of an injured Thoroughbred, allowing a rapid and successful return to racing at the previous level of racing performance.