The effect of synthetic human calcitonin gene-related peptide (hCGRP) on the isolated and electrically driven left atria of rats were investigated. The peptide at concentrations of 3 X 10(-9)-3 X 10(-7) M produced positive inotropic effects on the left atria in a dose-dependent manner. Verapamil (10(-5) M) and adenosine (10(-4) M) reduced the positive inotropic effect of hCGRP at concentrations of 3 X 10(-9) and 3 X 10(-8) M, but not at that of 3 X 10(-7) M. Ouabain (5 X 10(-5) M) inhibited the effect of hCGRP in concentrations of 3 X 10(-7) and 3 X 10(-8) M, but not in that of 3 X 10(-9) M. Simultaneous pretreatment with verapamil (10(-5) M) and ouabain (5 X 10(-5) M) suppressed the positive inotropy by hCGRP at all concentrations tested. On the other hand, tetrodotoxin (10(-6) M) potentiated only the positive inotropic effect of 3 X 10(-7) M hCGRP. Metoprolol (10(-7) M) and theophilline (10(-3) M) did not affect the inotropic effect of hCGRP. These results suggest that the positive inotropic effect of hCGRP is not mediated by beta-adrenoceptors but by two distinct mechanisms of action, which was inhibited by verapamil but not by ouabain (facilitation of Ca++ influx in lower concentrations of hCGRP) and which was blocked by ouabain but not by verapamil and potentiated by tetrodotoxin (inhibition of Na+/Ca++ exchange mechanism at higher concentrations of hCGRP).

Adenosine↗

PubMedDate not supplied

Calcitonin gene-related peptide increases in the dorsal root ganglia of adjuvant arthritic rat.

We examined the effect of adjuvant arthritis on the content of immunoreactive calcitonin gene-related peptide (iCGRP) in the dorsal root ganglia at L4-L6 levels and the spinal cord at a lumbar level in rats. Arthritis was induced by inoculating adjuvant into both hind-paws twice at a 10 day interval. In the arthritic rats 15 days after the first inoculation (day 15), the content of iCGRP was significantly increased in the dorsal root ganglia, with no change in the dorsal and ventral horns. The content in the dorsal root ganglia was still high on day 26 and had decreased by day 40. An intrathecal injection of colchicine (0.2 mg, 18 hr before killing) enhanced the increase of iCGRP in the dorsal root ganglia and decreased it in the dorsal horn of arthritic rats, although in noninoculated rats such treatment produced no significant changes in the content of iCGRP in both regions. The arthritis-induced increase in the content of iCGRP in the dorsal root ganglia was significantly reduced after treatment with the antiinflammatory analgesic, diclofenac sodium, in a dose of 3 mg/kg/day, PO for 10 days. Swelling and hyperalgesia in the hind-paw were depressed after such treatment. These results suggest that adjuvant arthritis with long-lasting inflammation with pain facilitates the turnover, especially biosynthesis, of CGRP in primary afferent neurons.

Animals↗

PubMedDate not supplied

Changes of secondary structure detected by laser Raman spectroscopy in model peptides of human alphaA-crystallin due to substitution of D-aspartyl residues for L-aspartyl residues.

PURPOSE: We have found that two aspartyl (Asp-151 and Asp-58) residues of alphaA-crystallin are inverted and isomerized to the biologically uncommon D-beta-Asp residues during aging. In order to elucidate the correlation between the formation of the D-beta-Asp isomer and the environment surrounding the Asp in the protein, we performed a Raman spectroscopic study using two synthetic peptides: T6 peptide containing Asp-58, and T18 peptide, containing Asp-151, which correspond to the tryptic peptides of human alphaA-crystallin. METHODS: Both T6 (Thr-Val-Leu-Asp(58)-Ser-Gly-Ile-Ser-Glu-Val-Arg) and T18 (Ile-Gln-Thr-Gly-Leu-Asp(151)-ala-thr-his-ala-Glu-Arg) peptides were synthesized with four optical isomers which have L-alpha-, D-alpha, L-beta and D-beta-aspartyl residues. These peptides were subjected to Raman measurement. RESULTS: The Raman spectrum of the L-alpha-Asp T18 peptide measured as dry powder revealed that the secondary structure of this peptide is mainly anti-parallel beta-sheet. The main structure of the D-beta-Asp T18 peptide when in dry powder form was altered to an alpha-helix and/or random structure. The main structure of L-alpha-Asp T18 peptide when measured in aqueous solution also converted to an alpha-helix and/or random structure. The conversion of L-alpha-to D-beta-Asp in T6 peptides when in dry powder form revealed no alteration of secondary beta-sheeted structure. CONCLUSION: Raman spectroscopy clearly revealed a large conformational change in the secondary structure of T18 peptide caused by substitution of normal L-alpha-Asp to biologically uncommon Asp-isomers. This result indicates that the inversion of an amino acid in a protein greatly affects the secondary structure of the protein.

Aspartic Acid↗

PubMedDate not supplied

Reorganization of myosin in surface-activated spreading platelets.

To study the localization of myosin in platelets, we utilized polyclonal antibody to heavy chain of platelet myosin. Both immunofluorescence and indirect immunogold staining techniques were employed. (1) In the unactivated platelets, myosin was distributed homogeneously throughout the cytosol. The cytosolic myosin was removed after platelets were treated with Triton X-100. The association of myosin with actin microfilaments in unactivated platelets was minimal. (2) In the surface-activated platelets, myosin was unextractable by Triton X-100. The myosin antibody heavily decorated the actin cable-networks which characterized the activated platelets. (3) In the Triton-unextractable cytoskeleton of both unactivated and activated platelets, we found fine fibrils (about 1-nm wide) that were often associated with immunogolds. These fibrils were similar to purified myosin molecules observed in rotary-shadowed metal replicas and ultrathin sections. These results indicate that cytosolic myosin becomes associated with actin cable-networks after the activation of platelets.

Blood Platelets↗

PubMedDate not supplied

High-dose chemotherapy with hematopoietic stem cell transplantation is effective for nasal and nasal-type CD56+ natural killer cell lymphomas.

CD56+ natural killer (NK) cell lymphomas occur frequently in the nasal and nasopharyngeal regions and carry a poor prognosis. We have studied seven cases with NK-cell lymphomas. These lymphomas showed the following immunophenotype: CD56+, CD2+, sCD3- and Epstein-Barr virus-encoded small RNAs (EBERs)+. Six patients had localized (stage I or II) disease involving the nasopharyngeal region, while one had stage III disease. One patient with stage I disease achieved a complete remission (CR) after treatment with involved-field irradiation, but subsequently relapsed and died. The remaining six patients received combination chemotherapy as primary treatment: five patients with localized stage I or II disease and one patient with advanced stage III disease. Responses to initial chemotherapy were generally poor. These six patients received a variety of salvage chemotherapy regimens, but never achieved a CR. Subsequently, four of six patients showed a highly aggressive clinical course and died of disseminated disease within 1 year from the diagnosis. Three of six patients received high-dose chemotherapy supported by syngeneic, autologous or allogeneic peripheral blood stem cell transplantation. Two of the three transplant patients achieved a CR and are now surviving in continuous CR. Our clinical experience suggests that myeloablative high-dose chemotherapy and bone marrow rescue by hematopoietic stem cell transplantation may be an effective salvage treatment modality for refractory NK-cell lymphomas and could be considered as a part of the initial therapy for these patients.

Adolescent↗

PubMedDate not supplied

Popliteal artery entrapment syndrome: accurate morphological diagnosis utilizing MRI.

A case of bilateral popliteal artery entrapment syndrome was accurately diagnosed utilizing magnetic resonance imaging (MRI) in a 34-year-old male with intermittent claudication. The abnormal structure was clearly visualized in relation to the popliteal artery in T1-weighted sagittal and axial sections of MRI. The type of entrapment was determined by this method prior to surgery. Intermittent claudication disappeared after surgical repair. Our experience emphasizes that MRI facilitates the accurate morphological diagnosis of popliteal artery entrapment syndrome.

Adult↗

PubMedDate not supplied

Treatment of endotoxemia with low-dose intramuscular injections or oral administration of polymyxin B.

Thirty patients with sepsis received 50,000 U of polymyxin B intramuscularly per day (n = 22) or 3 million U orally per day (n = 8). Plasma endotoxin levels were measured by the Endospecy test after treating the plasma with a new perchloric acid method. Plasma endotoxin levels were reduced to normal values (less than 9.8 pg/ml) in all the injected patients within two days and in all the orally treated patients within three days. Clinical symptoms were also ameliorated. No treatment side effects were reported. It is concluded that polymyxin B is a safe and effective treatment against endotoxemia.

Administration, Oral↗

PubMedDate not supplied

Perchloric acid, toxicolor, endospecy, and miconazole in the early diagnosis and treatment of fungemia.

As a procedure for the diagnosis of fungemia, Toxicolor and Endospecy (limulus tests using a synthetic chromogenic substrate) were used to measure (1----3)-beta-D-glucan (beta-glucan), which is a membranous component of fungus. The plasma samples were pretreated with a new perchloric acid method. These methods permit measurement of the beta-glucan within about two hours. Patients in whom fungemia was diagnosed were effectively treated with miconazole.

Adult↗

PubMedDate not supplied

Evaluation of IPM/CS in gram-negative bacillus infections: use of an endotoxin-specific assay.

The subjects were 26 patients hospitalized with severe trauma or burns. Twice daily for seven to 14 days, 1 gm of IPM/CS (a 1:1 combination of imipenem and cilastatin sodium) was administered by intravenous drip infusion to each patient. Clinical outcome was rated excellent in nine patients, good in 12, and fair in five. Bacteria, isolated in 21 of the 26 patients, were eliminated in 18 and decreased in three. Mean endotoxin levels, assessed by the Endospecy method, were reduced from 167.8 pg/ml before treatment to 5.1 pg/ml after treatment. No treatment side effects were noted.

Adult↗

PubMedDate not supplied

Metabolism of cholecystokinin-33 in vivo: effect of L-364,718, a CCK receptor antagonist.

Metabolism of cholecystokinin (CCK) and the effect of L-364,718, a specific CCK-A receptor antagonist, on the metabolism of CCK were examined in dogs. In conscious dogs, 45 min intravenous infusion of synthetic human CCK-33 (100 pmol/Kg/hr) caused an integrated CCK response over 90 min of 675 +/- 51 pmol-90 min/L, and the plasma CCK levels declined promptly with a t1/2 of 2.2 +/- 0.3 min after cessation. Organ extraction of CCK-33 by the kidney, mesenteric organs, and liver was examined in anesthetized dogs. From the gradients of the plasma levels between afferent and efferent vessels for each organ after bolus injection of CCK-33 (50 pmol/Kg), renal extraction ratio was 0.30 +/- 0.04, and mesenteric extraction ratio was 0.19 +/- 0.04. Hepatic extraction was not detected. T1/2 and extraction ratios were not affected by the preinjection of L-364,718 (20 nmol/Kg). The results indicate in dogs that exogenously administered CCK-33 is degraded by the mesenteric organs as well as the kidney but not by the liver, and that receptor-mediated mechanisms are not involved in these degradation pathways of CCK.

Anesthesia↗

PubMedDate not supplied

Correlation between the appearance of gelatinases in the synovial fluid of patients with rheumatoid arthritis and polymorphonuclear elastase, stromelysin-1, and the tissue inhibitor of metalloproteinase-1.

OBJECTIVE: To clarify whether gelatinases in the synovial fluid are related to rheumatoid arthritis (RA). METHODS: Gelatinases in the synovial fluid of patients with RA were analyzed by gelatin zymography. RESULTS: We classified patients into 3 distinct groups based on the gelatinases present. Although inactive gelatinase A was found in the synovial fluid of all patients with RA, the presence of gelatinase B varied: group I contained none, group II contained inactive gelatinase B, and group III contained active gelatinase B. The presence of gelatinase B was positively correlated with the polymorphonuclear (PMN) elastase content of the synovial fluid. Furthermore, the presence of activated gelatinase B correlated well with the stromelysin-1 content. Conversely, large amounts of the tissue inhibitor of metalloproteinase-1 (TIMP-1) were found in the synovial fluid of patients in group II. CONCLUSION: The appearance and form of gelatinase B may reflect the inflammatory condition of patients with RA.

Arthritis, Rheumatoid↗