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Background: Attacks of neuropathic pain, usually abdominal, are characteristic of the acute porphyrias and accompanied by overproduction of heme-precursor molecules, specifically delta-aminolevulinic acid and porphobilinogen. The basis for the acute symptoms in these diseases has been speculative., Methods: We review genetic acute porphyria, hereditary tyrosinemia, and an acquired condition, lead poisoning. All perturb heme synthesis and present with a similar pain syndrome., Results: Although each of these conditions has characteristic urine biochemistry, all exhibit excess delta-aminolevulinic acid. Moreover, in all, treatment with hemin reduces delta-aminolevulinic acid and relieves symptoms. In contrast, use of recombinant porphobilinogen deaminase to knock down porphobilinogen in acute porphyria was ineffective., Conclusions: There is now convincing evidence that delta-aminolevulinic acid is the cause of pain in the acute porphyrias. The efficacy of hemin infusion is due mainly, if not entirely, to its inhibition of hepatic delta-aminolevulinic acid synthase-1, the enzyme that catalyzes delta-aminolevulinic acid formation. Delta-aminolevulinic acid synthase-1 is a rational target for additional therapies to control symptoms in acute porphyria., (Copyright © 2015 Elsevier Inc. All rights reserved.)

The practice of veterinary medicine and research into both animal diseases and animal models of human disease are restricted by the scarcity of monoclonal antibodies (mAb) that react with animal proteins. One way to enlarge the repertoire of mAb to animal leukocyte differentiation antigens (LDA) is to test mAb specific to other species for cross-reactivity to the species of interest. We have tested a panel of 380 commercially available anti-human mAb for cross-reactivity to feline LDA. Twenty-six of these mAb cross-react with cat LDA and 19 others are of questionable cross-reactivity. Definition of mAb specificity in the cat is being investigated by multi-color flow cytometry (FCM) to compare test mAb specificity with that of mAb to known feline LDA. The addition of these cross-reactive mAb to the anti-feline mAb currently available will enhance studies in comparative medicine.

Environmental and/or occupational exposure to minerals, metals, and fibers can cause lung diseases that may develop years after exposure to the agents. The presence of toxic fibers such as asbestos in the environment plus the continuing development of new mineral or vitreous fibers requires a better understanding of the specific physical and chemical features of fibers/particles responsible for bioactivity. Toward that goal, we have tested aluminosilicate zeolites to establish biological and chemical structure-function correlations. Zeolites have known crystal structure, are subject to experimental manipulation, and can be synthesized and controlled to produce particles of selected size and shape. Naturally occurring zeolites include forms whose biological activity is reported to range from highly pathogenic (erionite) to essentially benign (mordenite). Thus, we used naturally occurring erionite and mordenite as well as an extensively studied synthetic zeolite based on faujasite (zeolite Y). Bioactivity was evaluated using lung macrophages of rat origin (cell line NR8383). Our objective was to quantitatively determine the biological response upon interaction of the test particulates/fibers with lung macrophages and to evaluate the efficacy of surface iron on the zeolites to promote the Fenton reaction. The biological assessment included measurement of the reactive oxygen species by flow cytometry and chemiluminescence techniques upon phagocytosis of the minerals. The chemical assessment included measuring the hydroxyl radicals generated from hydrogen peroxide by iron bound to the zeolite particles and fibers (Fenton reaction). Chromatography as well as absorption spectroscopy were used to quantitate the hydroxyl radicals. We found that upon exposure to the same mass of a specific type of particulate, the oxidative burst increased with decreasing particle size, but remained relatively independent of zeolite composition. On the other hand, the Fenton reaction depended on the type of zeolite, suggesting that the surface structure of the zeolite plays an important role.

The intraperitoneal inoculation of pigs with baculovirus-expressed transmissible gastroenteritis virus (TGEV) structural proteins (S, N, M) in conjunction with thermolabile Escherichia coli mutant toxin (LT-R192G) in incomplete Freund's adjuvant (IFA) was tested in an attempt to elicit active immunity to TGEV in gut-associated lymphoid tissues (GALT). Four groups of 63 (1-5-week-old) suckling, TGEV-seronegative pigs were used to assess the efficacy of the recombinant protein vaccine (group 3) in comparison with sham (group 1), commercial vaccine (group 2), and virulent TGEV Miller-strain-inoculated pigs (group 4). The TGEV-specific mucosal and systemic immune responses were measured after in vivo and in vitro stimulation with TGEV-antigens. The major T-cell subset distribution was analyzed in vivo and in vitro after stimulation of mononuclear cells with TGEV (from mesenteric lymph nodes of group 3 inoculated with TGEV-recombinant proteins). Induction of active immunity was assessed by challenge of pigs with virulent TGEV at 27 days of age. Baculovirus-expressed TGEV proteins coadministered with LT-R192G in IFA induced mesenteric lymph node immune responses associated with IgA-antibodies to TGEV and partial protection against TGEV-challenge. The high titers of serum IgG- and virus-neutralizing-antibodies to TGEV in group 3 pigs most likely reflected the dose of TGEV S-protein administered. At the day of TGEV-challenge, the in vitro stimulation of mononuclear cells from the mesenteric lymph nodes of group 3 pigs with inactivated TGEV resulted in an increase in double positive (CD4+CD8+), natural killer (CD2+CD4-CD8+dim) and cytotoxic (CD2+CD4-CD8+bright) T-cell phenotypes, accompanied by increased expression of interleukin-2 receptor and a decrease of the null (CD2-CD4-CD8-/SW6+) cell phenotype.

Two distinct strain-related patterns of organism-host interaction on dorsal tongue of immunocompetent rats have been identified for Candida albicans: some isolates induce mucosal lesions, while other isolates penetrate the keratin layer but do not produce a lesion. This study examined the behavior of each of the two types of isolates in a cyclosporin-immunosuppressed rat model. Groups B (normal) and D (cyclosporin) were orally inoculated with a lesion-inducing isolate of C. albicans, while a non-lesional isolate was given to Groups A (normal) and C (cyclosporin). A typical dorsal tongue lesion developed in 4/18 rats in Group B and in 13/16 in Group D (P = 0.00267). No significant difference in infection rate between the normal and cyclosporin-treated animals was seen for the non-lesional isolate. The lack of a host inflammatory response associated with the non-lesional isolate may represent an ecologic advantage for the organism.

A portoenterostomy (PE) procedure for extrahepatic biliary atresia (EHBA) is sometimes performed with a stoma in an attempt to reduce the incidence of acute cholangitis. The purpose of this study was to determine if the presence of a stoma increased the complication rate of patients undergoing orthotopic liver transplantation (OLT) for EHBA. The medical records of 42 consecutive patients with EHBA who underwent primary OLT between October 1988 and October 1991 were retrospectively reviewed. Three patients were excluded, since their grafts were lost within 3 days of OLT. The remaining 39 patients were divided into three groups: no PE (n = 7), PE without stoma (n = 23), and PE with stoma (n = 9). The mean age of the whole group was 19.62 +/- 24.37 months, with a range of 5 to 132 months. Mean weight was 9.62 kg, with a range of 4.2 to 41 kg. Survival at 3 and 12 months as well as number of retransplantations were similar among the three groups. However, at the time of OLT increased morbidity was observed, consisting of increased operative time and number of reoperations, whether or not the stoma had been closed prior to OLT.

Salvage of intraperitoneal blood with autotransfusion is a well-accepted practice. Laparoscopic examination is gaining popularity and holds diagnostic promise for the evaluation of trauma patients. We describe herein the successful combination of these techniques in a patient who sustained blunt abdominal trauma, facilitating splenic salvage, autotransfusion, and avoidance of laparotomy.

Ultrastructural, autoradiographic, immunofluorescent and biochemical techniques were used to characterize primary cultures of term placental cytotrophoblast in order to gain insight into the differentiation and secretory capacities of the cellular component of human trophoblast. Trypsin treatment of placental villi allowed isolation of a predominantly cytotrophoblast cell population that maintained viability up to 13 weeks in monolayer culture. Autoradiographic studies of tritiated thymidine incorporation identified a smaller diameter mononucleated cell population that was mitotically active and developed into larger diameter mononucleated cells and into multinucleated cells during culture. Ultrastructurally, cultured cells formed desmosomes, had an extensive network of cytoplasmic microfilaments and contained the organelles for hormone synthesis and secretion. These cells secreted steroid hormones, secreted Schwangerschafts protein I, actively incorporated tritiated glycoprotein precursors and expressed surface immunoreactivity for the beta-subunit of human chorionic gonadotrophin (hCG). However, medium concentrations of hCG and human placental lactogen dropped rapidly to undetectable levels after 14 days in primary culture. Cells grown beyond confluence differentiated into 1 to 2 mm structures with a villus-like histology. Our studies indicate that cytotrophoblast can secrete steroids, cytotrophoblast differentiation occurs in vitro in the absence of maternal tissues, hCG synthesis occurs in cultured cytotrophoblast and medium concentrations of placental protein hormones are not the best indicators of cell viability for cultures of cytotrophoblast.

A preliminary study demonstrated intracytoplasmic polyvalent immunoglobulin in human pleural fluid cells using a direct immunofluorescence technique. Of 33 pleural-fluid cell samples tested, 31 contained cells that initially stained positive for polyvalent immunoglobulin. The two negative specimens were from malignant effusions. Eleven of the specimens were cultured for seven days; nine of the eleven cultured specimens tested negative for polyvalent immunoglobulin after four days in culture. The remaining two specimens showed a marked decrease in positivity. After adding cell-free pleural fluid to the cultures on day four, the nine negative samples became positive again by day seven; the two slightly positive cases became strongly positive. The significance of these findings is discussed.