Protein kinase C, an enzyme that is activated by the receptor-mediated hydrolysis of inositol phospholipids, relays information in the form of a variety of extracellular signals across the membrane to regulate many Ca2+-dependent processes. At an early phase of cellular responses, the enzyme appears to have a dual effect, providing positive forward as well as negative feedback controls over various steps of its own and other signaling pathways, such as the receptors that are coupled to inositol phospholipid hydrolysis and those of some growth factors. In biological systems, a positive signal is frequently followed by immediate negative feedback regulation. Such a novel role of this protein kinase system seems to give a logical basis for clarifying the biochemical mechanism of signal transduction, and to add a new dimension essential to our understanding of cell-to-cell communication.

https://science.sciencemag.org/content/sci/233/4761/305.full.pdf

Studies and perspectives of protein kinase C

Evidence from pathology and epidemiology studies has been provided for a human model of gastric carcinogenesis with the following sequential stages: chronic gastritis; atrophy; intestinal metaplasia; and dysplasia. The initial stages of gastritis and atrophy have been linked to excessive salt intake and infection with Helicobacter pylori. The intermediate stages have been associated with the ingestion of ascorbic acid and nitrate, determinants of intragastric nitrosation. The final stages have been linked with the supply of beta-carotene and with excessive salt intake. Nitrosating agents are candidate carcinogens and could originate in the gastric cavity or in the inflammatory infiltrate.

https://cancerres.aacrjournals.org/content/canres/52/24/6735.full.pdf

Human Gastric Carcinogenesis: A Multistep and Multifactorial Process—First American Cancer Society Award Lecture on Cancer Epidemiology and Prevention

International Autoimmune Hepatitis Group Report: review of criteria for diagnosis of autoimmune hepatitis

Mise a jour: anatomopathologie, anomalies immunologiques et pathogenese, tests de laboratoire, manifestations cliniques et troubles associes, evolution, traitement

Primary biliary cirrhosis.

Spreading depression (SD) and the related hypoxic SD-like depolarization (HSD) are characterized by rapid and nearly complete depolarization of a sizable population of brain cells with massive redi...

https://www.physiology.org/doi/pdf/10.1152/physrev.2001.81.3.1065

Mechanisms of Spreading Depression and Hypoxic Spreading Depression-Like Depolarization

The serum level of pepsinogen I (PG I) and pepsinogen II (PG II), and the PG I/PG II ratio were compared with the surface area of the fundic mucosa, as determined endoscopically by the Congo red staining method. Reduction in the area of the fundic mucosa due to gastritis was associated with stepwise reduction in the PG I levels and the PG I/PG II ratios. Reduction in the area of the fundic mucosa was also associated with decreases in the basal acid output, maximal acid output (MAO), the basal pepsin output and the stimulated pepsin output. The best sensitivity and specificity levels for the diagnosis of normal mucosa and severe gastritis were obtained with the PG I/PG II ratio and the MAO. A retrospective study of 58 patients with gastric cancer and 162 cancer-free patients showed that a PG I/PG II ratio identified 86.2% of all carcinomas and 87.5% of early carcinomas. Although this test gave a positive rate of 36% among the cancer-susceptible age group controls, its use would lower the cost of mass screening by targeting a smaller test population.

Serum pepsinogens as a screening test of extensive chronic gastritis.

Radioimmunoassay of serum group I and group II pepsinogens in normal controls and patients with various disorders

Radioimmunoassay of human C-peptide was established using antiserum to synthetic human connecting peptide and synthetic tyrosylated human connecting peptide. Synthetic human connecting peptide and natural human C-peptide showed the same degree of cross-reactivity with the synthetic human connecting peptide antiserum. Natural human proinsulin reacted approximately one fourth as well as the human connecting peptide or natural human C-peptide when expressed on an equimolar basis.Synthetic porcine and bovine connecting peptide, human insulin and natural porcine proinsulin did not react with the human connecting peptide antiserum. Synthetic human connecting peptide did not cross with insulin antiserum. The senstitivity of the radioimmunoassay was 0.05ng/tube.The assay system was available to determine C-peptide immunoreactivity in plasma, because proinsulin and proinsulin-like components had been reported to be very low in plasma. The fasting level of C-peptide immunoreactivity in plasma of normal subjects assayed by this system was 0.88±0.21ng/ml.

Radioimmunoassay of human proinsulin C-peptide using synthetic human connecting peptide

Serum pepsinogen levels were measured in 137 stomach cancer patients and compared with those of 288 normal cancer-free subjects The serum pepsinogen levels of stomach cancer patients, especially pepsinogen I and the pepsinogen I/pepsinogen II ratio were significantly lower than those of normal controls and correlated well with the extent of chronic gastritis associated with the cancerous stomach These results were in good accordance with the results of previous studies indicating that the cancer derived from the stomach where chronic gastritis/intestinal metaplasia is extensive The high sensitivity and specificity of this non-invasive serum test to detect chronic gastritis suggested the possibility of its application to the mass screening of stomach cancer

Hiroshi Oka

Papers

Serum pepsinogens as a screening test of extensive chronic gastritis.

Radioimmunoassay of serum group I and group II pepsinogens in normal controls and patients with various disorders

Radioimmunoassay of human proinsulin C-peptide using synthetic human connecting peptide

The significance of low serum pepsinogen levels to detect stomach cancer associated with extensive chronic gastritis in Japanese subjects.

Streptococcal-related antigens stimulate production of IL6 and interferon-γ by T cells from patients with Behcet's disease