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New treatment regimens in organophosphate (diazinon) and carbamate (methomyl) insecticide-induced toxicosis in fowl.

The objective of this work was to determine optimal treatment regimens for organophosphate (OP) or carbamate insecticide toxicoses in fowl using the antidotes atropine sulfate and pralidoxime chloride (2-PAM). Broiler chicks in treatment groups, each comprising 3 replicates of 6-7 birds/replicate, were gavaged on a body weight (BW) basis with the OP and carbamate insecticides, diazinon and methomyl, respectively, at lethal dosages. Treatment groups were injected with either or both of the antidotes at various dosages as soon as clinical signs appeared. Birds appearing healthy 24 h thereafter were regarded as having been treated successfully. At a dosage of 100 mg/kg BW, atropine was mildly toxic and at 200 mg/kg 2-PAM was severely toxic (but not lethal), whereas at dosages of 50 and 100 mg/kg BW, respectively, the antidotes were at their most effective. With diazinon, atropine alone was only partially effective (12/20 survivors), whereas 2-PAM was extremely efficacious. (20/20 survivors); the combination of the 2 antidotes at 2 dosages was slightly less effective (19/20 survivors) than 2-PAM alone. For methomyl toxicity, atropine was largely successful (18/20 survivors), whereas 2-PAM was mostly unsuccessful (10/20 survivors); the combination at high dosage was less effective (15/20 survivors) than atropine alone, but at a low dosage the combination was the most successful (20/20 survivors). The results indicate that anticholinesterase insecticide toxicoses in fowl should not be treated according to textbook recommendations, and antidotal dosage with atropine should be up to 100 times greater than is commonly recommended. The specific cause of the toxicoses should ideally be determined before treatment is given, but as this is often unknown, a combination of antidotes may be the optimal treatment protocol.

Animals↗

[Treatment of chronic Wilson's disease in 2 patients using plasmapheresis--clinico-biochemical observations].

INTRODUCTION: The introduction of penicillamine in the treatment of Wilson's disease (hepatolenticular degeneration) was a historical event [1]. D-pericillamine (d-PAM) showed some potential side effects such as myasthenia, kidney toxicity, etc. In previous decade the treatment of Wilson's disease (WD) with zinc sulphate started successfully [4]. Danks [7] described the use of exchanged transfusions, peritoneal dialysis and plasmapheresis in the treatment of young patients with WD in acute liver failure. These patients had acute copper poisoning. The results of this study were beneficial. MATERIAL AND METHODS: Therapeutic plasmapheresis (PF) has been used in many diseases in which immunological mechanisms are proved [8, 9]. We started with using PF in the treatment of two young chronic patients with Wilson's disease. The clinical picture of patients became worse, probably due to the decrease in cupriuretic effect of d-PAM. One patient (1) did not take d-PAM regularly. In this study PF was performed with the use of haemonetics V-50 and filter 704. During the treatment with PF, 2000 ml of plasma was always exchanged, i.e. removed. During the treatment with PF the patients were hospitalized at the Department of Neurology and Psychiatry of Children and Young People. CASE REPORT AND RESULTS: Patient No. 1. A 24-year-old man, born in 1965, came with a coarse tremor. He has been diagnosed as WD at the age of 18. Kayser-Fleischer rings were found in the cornea by slit-lamp examination. The disease began when he was 15 years old with polymorphous difficulties. In time tremor became more severe. It was apparent when the patient made any movement. The first treatment with PF (1) lasted from February 13 to March 16, 1989. The patient had 10 PF without any side effect. During the treatment with PF the patient felt better. After PF-tremor was reduced significantly, and subjective and objective condition ameliorated. The patient (1) was readmitted to the hospital on June 24, 1991 for continuation of the treatment with PF. Anamnestic data and neurological examination revealed progression of the disease. His condition became worse, especially tremor. He could not write a single letter (Figures 1-5) and walk without help of the others. His tremor became the severest when he made any kind of voluntary movement. The second treatment with PF started on June 25, 1991 and finished on July 16, 1991. He received 9 PF in this series. The treatment was without side effects. Tremor was reduced approximately by 15%. Plasma copper examined before and after 9 PF showed different values (Table 2). This difference (2.79 mumol/l; 23.70%) in plasma copper level was removed from circulation. Patient No. 2. A 23-year-old man, born in 1966, came to the hospital with acute exacerbation of WD. At the age of 16 latent psychosis was diagnosed. One year later diagnosis of WD was established in the hospital when he was 17 years old. Kayser-Fleischer rings were found in the cornea by slit-lamp examination. The treatment with d-PAM and other drugs (BAL, symptomatic therapies, sedatives, antidepressants, etc.) has been accompanied with good and long-term remissions and short exacerbation. A few years later exacerbation became longer and longer and worse and worse. He was admitted to the hospital on November 28, 1989 with acute relapse of WD. His condition was very difficult, completely bedridden. The treatment with PF started on December 26, 1989 and lasted to January 25, 1990. The treatment with PF was without d-PAM. He was only given symptomatic therapies. After a few PF he demonstrated side effects with nausea, sometimes vomiting, face sweating, pulse rate of about 120/min while blood pressure was normal. Therefore he was given human albumin in the next day, and no side effects were observed. The removal of little plasma copper from blood circulation correlated well with a small improvement in clinical symtpomatology. The rigidity was reduced and voluntary movements bec

Adult↗

Analysis of residual solvents in pharmaceuticals with purge-and-membrane mass spectrometry.

A method using purge-and-membrane mass spectrometry (PAM-MS) was developed for the analysis of residual solvents in pharmaceutical products. The method combines dynamic headspace and membrane inlet mass spectrometry. The limits of detection for the compounds studied, benzene, toluene, chloroform, 2-pentene and 2-methyl- and 3-methylpentane, were 0.05-0.1 mg/kg. In quantitative analysis the method showed good linearity (r(2) > 0.998) and acceptable within-day (RSD = 7.9-18%) and between-day (RSD = 6.8-10%) repeatability. The PAM-MS method combined with the custom-made Solver program was compared with a method using purge-and-trap gas chromatography/mass spectrometry (P&T-GC/MS) for identification of residual solvents from authentic samples. The results showed that PAM-MS/Solver provides reliable identification of the main volatile organic compounds (VOCs) in the pharmaceuticals, but VOCs with low concentrations (below 0.5 mg/kg) were better identified by P&T-GC/MS. Other advantages of the PAM-MS method were short analysis times and non-requirement for pre-treatment of samples.

Alkenes↗

Chemoimmunotherapy of disseminated malignant melanoma with DTIC-BCG, transfer factor + melphalan.

The experimental synergism of melphalan with DTIC and the ability of transfer factor to improve immunocompetence were the basis of an attempt to improve therapeutic results in disseminated malignant melanoma. Sixty-four evaluable patients with disseminated malignant melanoma were treated in a 21-day cycle as follows: DTIC 250 mg/M2 intravenously days 1 to 5, Connaught BCG 6 X 10(8) organisms on days 7, 12, and 17 by scarification, and transfer factor 1 unit (10(9) lymphocytes equivalent, from immunocompetent relatives of patients) subcutaneously on day 12, with or without L-PAM 30 mg/M2 on day 1. Twenty-nine patients received L-PAM and 35 did not. Remission rates of 17% and 23%, respectively, occurred in these groups. An additional 15 patients received DTIC-BCG and three doses of transfer factor on days 7, 12, and 17 and had a remission rate of 20%. Remission duration and survival were compared to historical controls of 111 patients treated with DTIC and 89 treated with DTIC-BCG. Median survival on DTIC-BCG-Transfer Factor was seven months compared to four months for DTIC (P = .003) but did not differ from DTIC-BCG. Addition of L-PAM did not improve remission duration or survival compared to DTIC-BCG but enhanced myelosuppression and immunosuppression. A 60% increase in delayed type hypersensitivity to recall antigens occurred in this study compared to 34% with DTIC-BCG (P = .005). Prognosis and immunocompetence were not directly related. In summary, in this study, (1) transfer factor therapy did not enhance the clinical effects of DTIC-BCG, although it augmented delayed type hypersensitivity to recall antigens; and (2) L-PAM was not additive to DTIC in the treatment of disseminated malignant melanoma and may have abrogated the effect of immunotherapy.

Adult↗

Structural characterization of lipopeptide agonists for the bradykinin B2 receptor.

The conformational features of Pam-Lys(0)-Arg(1)-Pro(2)-Pro(3)-Gly(4)-Phe(5)-Ser(6)-Pro(7)-Phe(8)-Arg(9)-OH (PKD) and Pam-Gly(-1)-Lys(0)-Arg(1)-Pro(2)-Pro(3)-Gly(4)-Phe(5)-Ser(6)-Pro(7)-Phe(8)-Arg(9)-OH (PGKD), the Pam-Lys and Pam-Gly-Lys analogues of bradykinin, have been determined by high-resolution NMR in a zwitterionic lipoid environment. Radical-induced relaxation of the (1)H NMR signals was used to probe the topological orientation of the peptides with respect to the zwitterionic lipid interface. The radical-induced relaxation and molecular dynamics (MD) data indicated that the palmitic acid and N-terminal amino acid residues embed into the micelles, while the rest of the polypeptide chain is closely associated with the water-micelle interface. Throughout the entire nuclear Overhauser effect restrained MD simulation, a nonideal type I beta-turn was observed in the C-terminus of PKD between residues 6 and 9, and a gamma-turn was observed in the C-terminus of PGKD between residues 6 and 7. Therefore, the additional glycine has a dramatic effect on the structural preferences of the biologically important C-terminus, an effect brought about by the interaction with the lipid environment. These structural features are correlated to the biological activity at the bradykinin B2 receptor.

Amino Acid Sequence↗

In situ alkylation with acrylamide for identification of cysteinyl residues in proteins during one- and two-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis.

Cysteinyl residues in proteins were alkylated with acrylamide during sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) to yield a thioether derivative, cys-S-beta-propionamide (PAM cys). The process was termed in situ alkylation with acrylamide. Using this method, the recovery of PAM-cys peptides from bovine serum albumin (BSA) was 88.6% at 10 picomol in one-dimensional (1-D) SDS-PAGE and 97.1% at 50 picomol in two-dimensional (2-D) SDS-PAGE. The coverage of tryptic peptide of BSA in 1-D and 2-D SDS-PAGE was 83.7% and 81.1%, respectively. The advantages of in situ alkylation with acrylamide were the following: (i) cysteinyl peptides were effectively derived in a single PAM cys and then proteins were precisely identified using databases; (ii) marked reduction of salts compared with post alkylation, e.g., using carboxymethylamide (CAM), resulting in higher signal intensity and wider coverage of cysteinyl peptides from PAM cys, compared with those of CAM derivatives, in mass spectrometry peptide mapping; and (iii) shorter duration by excluding the processes of post alkylation and desalting before peptide mapping.

Acrylamide↗

Preclinical warning of recrudescent mammary cancers by pregnancy-associated alpha-macroglobulin.

Nine of 30 mammary cancer patients developed metastases during 13-94 months after mastectomy. All 9 patients had elevated blood levels of pregnancy-associated alpha-macroglobulin (PAM) 1-21 months before conventional detection of metastases. Seven of the clinically well patients had PAM rises exceeding 90 per cent above the baseline and in 4 of these the PAM later fell to lower levels. PAM appears to have potential as an indicator of the growth of micrometastases.

Adult↗

Binding of lipopeptide to CD14 induces physical proximity of CD14, TLR2 and TLR1.

Lipoproteins or lipopeptides (LP) are bacterial cell wall components detected by the innate immune system. For LP, it has been shown that TLR2 is the essential receptor in cellular activation. However, molecular mechanisms of LP recognition are not yet clear. We used a FLAG-labeled derivative of the synthetic lipopeptide N-palmitoyl-S-[2,3-bis(palmitoyloxy)-(2R,S)-propyl]-(R)-cysteinyl-seryl-(lysyl)(3)-lysine (Pam(3)CSK(4)) to study the roles of CD14, TLR2 and TLR1 in binding and signaling of LP and their molecular interactions in human cells. The activity of Pam(3)CSK(4)-FLAG was TLR2 dependent, whereas the binding was enabled by CD14, as evaluated by flow cytometry and confocal microscopy. Using FRET and FRAP imaging techniques to study molecular associations, we could show that after Pam(3)CSK(4)-FLAG binding, CD14 and Pam(3)CSK(4)-FLAG associate with TLR2 and TLR1, and TLR2 is targeted to a low-mobility complex. Thus, LP binding to CD14 is the first step in the LP recognition, inducing physical proximity of CD14 and LP with TLR2/TLR1 and formation of the TLR2 signaling complex.

Animals↗

TLR2 engagement on CD8 T cells lowers the threshold for optimal antigen-induced T cell activation.

TLR have a crucial role in the detection of microbial infection in mammals. Until recently, most investigations on TLR have focused on cells of the innate immune system and on the role of TLR in the initiation of antigen-specific responses following recognition of microbial products by APC. Here, we report that murine T cells express TLR1, TLR2, TLR6, TLR7 and TLR9 mRNA. Using CD8 T cells from F5 TCR-transgenic mice, we demonstrate that the lipopeptide Pam(3)CysSK(4) (Pam), a synthetic analog of bacterial and mycoplasmal lipoproteins that recognizes TLR1/2 complex, costimulates antigen-activated T cells. Costimulation with Pam permits an increased cell proliferation and survival associated with a sustained CD25 expression and an enhanced expression of Bcl-xL anti-apoptotic protein. In addition, we show that costimulation with Pam up-regulates IFN-gamma production but also granzyme B secretion and cytotoxic activity of antigen-activated T cells, indicating that TLR2 engagement enhances the major effector functions of CD8 T cells. Finally, we demonstrate that TLR2 engagement on T cells lowers the activation threshold for costimulatory signals delivered by APC.

Animals↗

Peptidylglycine alpha-amidating monooxygenase- and proadrenomedullin-derived peptide-associated neuroendocrine differentiation are induced by androgen deprivation in the neoplastic prostate.

Most PCs show NE differentiation. Several studies have tried to correlate NE expression with disease status, but the reported findings have been contradictory. Prostatic NE cells synthesize peptides with a wide spectrum of potential functions. Some of these active peptides, such as PAMP, are amidated. PAM is the only carboxy-terminal peptide-amidating enzyme identified. We studied expression of PAMP and PAM in normal prostate and prostatic tumors (clinical specimens and human xenograft models) with or without prior androgen-deprivation therapy and found a wide distribution of both molecules in NE subpopulations of all kinds. Although the correlation of either marker to tumor grade, clinical progression or disease prognosis did not reach statistical significance, PAMP- or PAM-immunoreactive cells were induced after androgen-blockade therapy. In the PC-310 and PC-295 androgen-dependent models, PAMP or PAM NE differentiation was induced after castration in different ways, being higher in PC-310, which might explain its long-term survival after androgen deprivation. We show induction of expression of 2 new NE markers in clinical specimens and xenografted PC after endocrine therapy.

Adrenomedullin↗

Inhibition of DNA repair and the enhancement of cytotoxicity of alkylating agents.

DNA damage was evaluated by flow cytometric (FCM) analysis of cells treated with L-phenylalanine mustard (L-PAM) and stained with anti-DNA monoclonal antibody (MAb) F7-26. DNA damage was rapidly repaired, as indicated by the loss of DNA immunoreactivity after removal of L-PAM. Two types of drug combinations were found to inhibit DNA repair. Combinations containing inhibitors of DNA polymerase (ara-C, aphidicolin) or these inhibitors and hydroxyurea inhibited DNA repair in A2780/PAM and A549 cells. The inhibition of DNA repair by combinations of DNA-damaging agents thioTEPA or cisplatin and DNA polymerase inhibitors is a novel observation based on the specificity of DNA damage assay with MAb F7-26. Combinations containing thioTEPA or cisplatin inhibited DNA repair in A549 but not in A2780/PAM cells. Drug combinations which inhibited DNA repair also significantly enhanced cell killing by L-PAM. Cell survival in cultures treated with L-PAM and efficient inhibitors was 2 to 3 orders of magnitude lower than was expected for additive survival. ThioTEPA and cisplatin play a dual role in combination chemotherapy by inducing DNA damage and inhibiting repair of DNA damage. FCM analysis of DNA repair may be a useful component of drug evaluation and could be applied to determine cell-type specific sensitivity to inhibitors of DNA repair.

Alkylating Agents↗

Establishment of L1210 leukemia cells resistant to the distamycin-A derivative (FCE 24517): characterization and cross-resistance studies.

N-deformyl-N-[4-N,N-bis(2-chloroethylamino)benzoyl] distamycin-A (FCE 24517) is a new cytotoxic anti-tumor agent in phase-1 clinical trials. We have isolated stable FCE-24517-resistant cell sublines from murine leukemia L1210 cells by in vitro exposure to the drug. FCE 24517 selects a mixed population of resistant cells: the L1210/24517(1) cell line in vitro was in fact resistant to the selecting agent (RI 48.3), as well as to L-PAM (RI 5.4) and DX (RI 8.6) and over-expressed the mdr-I gene. When L1210/24517(1) cells were implanted in vivo and evaluated for sensitivity to the same agents, resistance was observed only to FCE 24517 and partially to L-PAM, whereas DX had the same anti-tumor efficacy as on the sensitive line. The clone derived from the above subline (L1210/24517(2)) was resistant to FCE 24517, distamycin-A and other cytotoxic compounds bearing the distamycin-A skeleton, and fully sensitive to DX and other anti-tumor compounds involved in the multi-drug resistance mechanisms, with a complete disappearance of the mdr phenotype. L1210/24517(2) cell line is partially cross-resistant to L-PAM, this resistance being accounted for by higher GSH intracellular levels, which however do not influence the resistance to FCE 24517. In fact, BSO treatment was capable of significantly modifying only the cytotoxicity of L-PAM. Our data suggest that L1210/24517(2) cells present a mechanism of resistance specific for FCE 24517 and related molecules.

Animals↗

Characteristics of bovine alveolar macrophage elastase.

Lavage of isolated bovine lung lobes was used to retrieve pulmonary alveolar macrophages (PAM). Nominal yields of 72 million viable PAM were routinely obtained using 500 ml of calcium- and magnesium-free phosphate-buffered saline. Bovine PAM readily attached to glass coverslips and within 24 hours, provided cell monolayers consisting exclusively of macrophages. Bovine PAM synthesized and secreted a calcium-dependent elastase in serum-free media. Optimal proteolytic activity using a radiolabeled elastin substrate was observed at pH 7.6. The elastase was insensitive to synthetic peptide chloromethyl ketone elastase inhibitors and to the serine protease inhibitor, phenylmethylsulfonyl fluoride. Enzyme activity, however, was effectively inhibited by the metal chelator, ethylenediaminetetraacetic acid, or suppressed by inhibition of protein synthesis with cycloheximide.

Animals↗

The ontogeny of pulmonary alveolar macrophages in parabiotic mice.

A bilateral distribution of labeled blood monocytes was achieved by unilaterally labeling donor members of surgically parabiosed B6D2F1/J mice with tritiated thymidine (3HTdR). Labeled pulmonary alveolar macrophages (PAM) were found in lung lavage fluid of donors. By contrast, no labeled PAM were found in lung lavage fluid from unstimulated recipients, even 12 days after labeling. Contralateral 3HTdR flash labeling showed that in recipients 3%, or about 10(4), PAM were in S phase of the cell cycle. Contralateral intratracheal challenge of recipient members with either Corynebacterium parvum vaccine or with Salmonella typhimurium lipopolysaccharide induced the emigration of labeled blood monocytes of donor origin into recipient alveoli. These data show that in parabiotic mice, blood monocytes do not regularly enter the alveolar compartment. It may be concluded that monocytes are not needed on a daily basis to sustain PAM populations.

Animals↗

Isolation and functional expression of human pancreatic peptidylglycine alpha-amidating monooxygenase.

Pancreastatin (PST) is processed from chromogranin A and the C-terminal amide of the peptide is an absolute requirement for biological activities. Human pancreatic carcinoma cells QGP-1 which produce both chromogranin A and PST were used to isolate cDNAs encoding two forms of peptidylglycine alpha-amidating monooxygenase (PAM). The two forms are a full length bifunctional enzyme and a variant lacking the transmembrane domain-coding region. When the cDNAs of these two forms were expressed in COS-7 cells, cells transfected with the predicted soluble form released into the culture medium a very much higher amidating activity which converts human chromogranin A-(273-302) to PST-29. The optimal pH for amidating activity was 5.4 and Cu2+, ascorbate and catalase were required as cofactors for the both forms of PAM. Km values for the membrane-bound and the soluble forms of PAM were 15.7 +/- 3.1 microM and 12.4 +/- 1.6 microM, respectively. These results demonstrate that both forms of PAM can function in the posttranslational processing of chromogranin A to PST in the environment of a secretory vesicle.

Amino Acid Sequence↗

Prevalence and turnover of peptidylglycine alpha-amidating monooxygenase mRNA in atrial cardiomyocytes.

Peptidylglycine alpha-amidating monooxygenase (PAM), the enzyme responsible for the alpha-amidation of neuroendocrine peptides, is more prevalent in the atrium of the heart than in pituitary or brain. RNase protection assays indicate that PAM transcripts account for approximately 0.5% of the mRNA in the neonatal atrium and 0.06% of the mRNA in the neonatal ventricle. In primary atrial cardiomyocyte cultures PAM mRNA turns over slowly, with a half-life of approximately 20 h. Levels of PAM mRNA in primary atrial cardiomyocytes are increased to 16.5% of control upon treatment with dexamethasone and decreased to 63% of control upon treatment with thyroid hormone.

Animals↗

In vitro selective effect of melphalan on human T-cell populations.

In vitro treatment with 2 micrograms/2 X 10(6) cells melphalan (L-PAM: L-phenylalanine mustard) significantly decreased the total number of T lymphocytes from peripheral blood (PBL) of healthy human donors and of the OKT4 population (precursor suppressor/helper/inducer) T cells as defined by monoclonal antibodies OKT3 and OKT4, respectively. No changes in the OKT+8 lymphocyte population (cytotoxic/mature suppressor cells) were observed following the same treatment. Preincubation of PBL with L-PAM at concentrations that do not affect the rate of DNA synthesis in PHA-stimulated lymphocytes inhibited the generation of T suppressor lymphocytes by ConA, as shown by their effect on PHA stimulation. Treatment of allogeneic PBL with L-PAM had no effect on mature suppressor T cells already induced by ConA, as shown by incubation of PBL with L-PAM after incubation with ConA.

Antibodies, Monoclonal↗

Lack of experimental vesicant activity for the anticancer agents cisplatin, melphalan, and mitoxantrone.

Cisplatin and L-PAM are DNA-crosslinking anticancer agents which have not been systematically studied for vesicant potential. Mitoxantrone is a new active anthracene-based, DNA intercalator which is undergoing widespread clinical testing for antitumor efficacy in man. These three agents were tested for vesicant activity in dehaired BALB/c mice given ID injections equivalent to human clinical doses. Neither cisplatin (up to 150 mg/m2) nor L-PAM (up to 71 mg/m2) produced any skin necrosis in the mice. The L-PAM solvent (acid/alcohol in propylene glycol) was ulcerogenic if injected undiluted. Mitoxantrone (up to 14 mg/m2) was not ulcerogenic in the mice, although the skin site retained a blue drug discoloration for several weeks. It is concluded that in clinically relevant doses, cisplatin, L-PAM, and mitoxantrone are not vesicants.

Animals↗