Esterase inhibitors prevent lysosomal enzyme redistribution in two noninvasive models of experimental pancreatitis

Earlier studies have indicated that lysosomal enzymes such as cathepsin B become redistributed within pancreatic acinar cells during the early stages of both diet- and secretagogue-induced acute pancreatitis. As a result, cathepsin B and digestive zymogens became colocalized within large cytoplasmic vacuoles. As cathepsin B can activate trypsinogen, this colocalization could result in intracellular digestive enzyme activation. The present study investigates the protective effects of gabexate mesilate (FOY) and camostate (FOY 305) on both of these noninvasive models of experimental pancreatitis. These esterase inhibitors prevented the hyperamylasemia, pancreatic edema, and acinar cell vacuolization that characterize secretagogue-induced pancreatitis and the hyperamylasemia and mortality that characterize diet-induced pancreatitis. In addition, FOY and FOY 305 were found to significantly decrease the subcellular redistribution of cathepsin B that occurs in both models. These findings indicate that enzyme activity sensitive to inhibition by FOY and FOY 305 may be critical to the redistribution phenomenon that characterizes both of these models of pancreatitis.

Identification and subcellular localization of proteins that are rapidly phosphorylated in tyrosine in response to colony-stimulating factor 1

To investigate growth factor-mediated signal transduction, we have studied phosphorylation events that take place within seconds of the binding of colony-stimulating factor 1 (CSF-1) to its cell-surface receptor. CSF-1 stimulated rapid tyrosine phosphorylation of cellular proteins in murine BAC1.2F5 macrophages at 37 degrees C and 4 degrees C. The pattern of CSF-1-stimulated tyrosine phosphorylation of at least 15 different proteins at both temperatures was similar and unchanged by treatment of the lysate with reducing agent. With the exception of the 185-kDa CSF-1 receptor, a 260-kDa protein and a 133-kDa protein, the proteins were predominantly cytoplasmic. At 37 degrees C, all the proteins were phosphorylated within 30 sec of addition of growth factor. At 4 degrees C, CSF-1 receptor sites were saturated after 2 min of incubation in the presence of high concentrations of CSF-1 and differences in the order of appearance of phosphorylated proteins were observed: 185 kDa (CSF-1 receptor) (by 2 min); 99 kDa (by 4 min); 125 kDa (by 10 min); 61 kDa (by 30 min); and 260 kDa, 84 kDa, and 41 kDa (by 180 min). In addition to stimulating the phosphorylation of these proteins in tyrosine, CSF-1 caused dephosphorylation of phosphorylated serine residues on the receptor. As neither CSF-1 nor its receptor is internalized at 4 degrees C, analysis of these early reactions and the phosphotyrosine-containing proteins in intact cells under these conditions should lead to an understanding of the early events in growth factor receptor-mediated signal transduction.

Localization of galanin immunoreactivity in the opossum esophagus

Galanin-like immunoreactivity was studied at 7 levels of the opossum esophagus, lower esophageal sphincter (LES) and adjacent portion of the stomach by indirect immunofluorescence; it was restricted to nervous structures. The majority of myenteric and submucous neurons were galanin-positive and received positive axo-somatic terminations. They also sent out axons staining positively. Galanin-positive fibers and a few atypically located neurons formed a mucous plexus at the bases of mucous glands. Varicose galanin fibers innervated the muscularis mucosae, circular and longitudinal muscle layers, while thick fascicles traversed the muscularis mucosae and circular muscle, possibly interconnecting the myenteric, submucous and mucous plexuses. Galanin-positive fibers did not supply blood vessels. There was no obvious gradient of innervation density along the esophagus, but the sphincter appeared to be more densely innervated than the esophageal body. There was no galanin-positive input to striated muscle. In view of its widespread distribution, this neuropeptide may serve multiple functions in the esophagus.

Atypical localization of myenteric neurons in the opossum lower esophageal sphincter

This study investigated sphincter-body differences in neuronal density and morphometry between the esophageal sphincter and body with a view to determining whether previously reported differences are authentic. The anatomical limits of the opossum lower esophageal sphincter were correlated with its physiological behavior by manometric demarcation. Following this, peeled whole mounts and paraffin and cryosections were used to study the morphology and morphometry of the esophageal myenteric plexus. Thirty animals were used and seven quantitated. The plexus of the esophageal body was located as usual in a plane between the longitudinal and circular muscle, which coincided with the plane of cleavage when these muscle layers were peeled apart for studying the plexus in whole mounts. In contrast, the plexus was located in several planes in the lower esophageal sphincter, which had no cleavage plane. Therefore, peeling the sphincter removes neurons and yields falsely low counts, making peel preparations of this region unsuitable for neuronal quantitation. In paraffin sections, the neuron density in the esophageal body 7 cm above the sphincter was 6,353 +/- 850/cm2, but decreased significantly to 2,254 +/- 353/cm2 at the 1-cm segment. In the lower esophageal sphincter, the neuronal count increased again to 8,530 +/- 1,606/cm2. Flash-frozen cryosections, which produced neuronal morphology similar to the in vivo condition, showed that there was no difference in neuronal size between esophageal body and sphincter. These studies show that atypical myenteric plexus localization causes spuriously low neuronal counts reported in the lower esophageal sphincter and that reported neuronal size differences are technique-dependent.

The management of congenital talipes equinovarus in developing countries

Congenital Talipes Equinovarus often remains untreated in developing countries. At our Institute in Calcutta, where we have modern facilities, a programme was undertaken using simple techniques in selected cases. Since 1964, 5,312 cases of congenital talipes equinovarus were treated by percutaneous elongation of the Achilles tendon, plantar fasciotomy and corrective plasters. In 4,502 cases the results are good enough to recommend this technique, even in developed countries.

Purification of the colony-stimulating factor 1 receptor and demonstration of its tyrosine kinase activity

Colony-stimulating factor 1 (CSF-1) regulates the survival, proliferation, and differentiation of mononuclear phagocytes. The CSF-1 receptor was purified from cell membranes of the J774.2 mouse macrophage cell line by solubilization with Triton X-100, CSF-1 affinity chromatography, and gel filtration. The purified receptor is a protein or glycoprotein of 165 kDa comprising a single polypeptide chain that is not covalently associated, either as a homopolymer, or with any other protein. CSF-1 stimulated autophosphorylation of the purified receptor in tyrosine residues. Casein but not histone was shown to act as a substrate for the tyrosine protein kinase activity of purified receptor.

A rapid silver-free method for staining the myenteric plexus

A method is presented for the relatively rapid demonstration of the myenteric plexus. Saturated Sudan black B in 70% ethanol followed by 0.01% aqueous buffered thionein were used on intestinal peels (whole-mounts) to stain myelinated and unmyelinated fibers and neuron cell bodies, respectively. In contrast to accepted silver methods, these two kinds of fibers were distinguished clearly; Schwann cell nuclei and nodes of Ranvier were visible. Preparations had the following attributes: relatively low optical density coupled with high visual contrast, freedom from metallic "mirroring," low background staining of subjacent muscle fibers, and presentation of a polychromatic picture. The entire procedure was under the complete and repeatable control of the operator. Perikaryon and nuclear morphology were clearly demonstrated. The limitations of this method are that it does not provide good visualization of individual unmyelinated neuronal processes and does not permit preparation of permanent slides.

Phosphate repression of phage protein synthesis during infection by choleraphage phi 149

A synthetic medium for choleraphage phi 149 growth, in which the concentration of phosphate ions plays a significant role, has been defined. Upon infection, choleraphage phi 149 DNA binds to the cell membrane at three to four sites. The host macromolecular syntheses are shut off by 10 min after infection and the synthesis of phage-specific DNA is detectable after 20 min of infection. The phage utilizes primarily the host DNA degradation products for its own DNA synthesis. When added during the first 20 min of infection both nalidixic acid and novobiocin inhibit phage growth. The effects of these antibiotics are not pronounced when added late during infection. Pulse labeling of ultraviolet-irradiated infected cells at different times during infection has allowed identification of about 50 phage-specific proteins of which 19 are structural proteins. These proteins appear during the infection cycle in two distinct phases, early and late. When infection is carried out in high-phosphate medium, none of the late proteins is synthesized. Eleven of the 26 early proteins detected are DNA-binding proteins.

Comparative studies on calotropins DI and DII from the latex of Calotropis gigantea

Autodigestion of two cysteine proteinases, calotropins DI and DII isolated from the latex of Calotropis gigantea, has been studied at pH 7.5 and 37 degrees C in the presence of an activating agent. Calotropin DI is more susceptible to autodigestion than calotropin DII. During autodigestion no interconversion of one calotropin to another has occurred, as verified by polyacrylamide gel electrophoresis in the presence and absence of sodium dodecyl sulfate. Immunologically, both calotropins are closely related, but they differ from papain and ficin. Both calotropins have blocked N-terminal amino acid residues. Their C-terminal amino acid sequences, determined by treatment with carboxypeptidase Y, are -(Pro, Ala)-Ala-Val-Tyr for calotropin DI and -(Ala, Val)-Ala-Pro-Tyr for calotropin DII. The tryptic peptide maps of their reduced and S-carboxymethylated derivatives suggest that both calotropins share a high proportion of common regions in their amino acid sequences. Calotropins DI and DII are two distinct proteinases, and they do not appear to be produced by autodigestion of a single precursor. Although they are inert to the common synthetic substrates of papain and ficin, their specificities toward oxidized insulin B chain are comparable to those of papain and ficin.

Duration of meiosis and spermiogenesis in the dog

The duration of meiosis and spermiogenesis was studied in the dog by following the kinetics of [3H]thymidine-labeled canine spermatocytes autoradiographically. Leptotene appears to last for at least 4.20 days, zygotene for less than a day, and pachytene for about 15.50 days. The transition from diplotene to metaphase II is extremely rapid and requires approximately a day. The duration of spermiogenesis is at least 19.60 days. Both meiosis and spermiogenesis are completed by 42.15 days.

Management of fusiform ascending aortic aneurysms

Thirteen patients had elective surgical treatment of fusiform ascending aortic aneurysms at Strong Memorial and Rochester General Hospitals from 1970 to 1978. There were 8 men and 5 women ranging in age from 51 to 78 years (mean, 61 years). Nine patients underwent composite tube graft and aortic valve replacement, 3 had aortic valve replacement plus supracoronary tube grafts, and 1 had aortic valve replacement plus aneurysmorrhaphy. Coronary reimplantation alone or combined with saphenous vein bypasses was fashioned in 10 patients. Potassium cardioplegia was considered a useful adjunct in 6 patients. Two early deaths accounted for an operative mortality of 15.4%. There were 3 late deaths. Eight patients are alive and well 2 to 109 months after operation.

Investigation of glycopyrrolate as a premedicant drug

The clinical efficacy of glycopyrrolate, a synthetic anticholinergic drug, for premedication was compared in a double-blind study with that of atropine or hyoscine in patients anaesthetized with diethyl ether. The antisialogogue actions of the three drugs were similar. Glycopyrrolate produced less tachycardia, pyrexia and blurred vision than atropine, and its sedative effect was less than that of hyoscine.