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Concentrations of serum proteins and erythrocyte sedimentation rate in patients with different histological types of gastric carcinoma.

ESR and serum concentrations of IgG, IgA, IgM, C3, C4, C1-INH and CEA were quantified preoperatively in 195 patients with gastric carcinoma. The values were grouped according to the extent of disease (T1-3N0M0, T2-3N + M0, T4AnyNM0, AnyTAnyNM1) and according to the histological type of tumor (intestinal-type, diffuse and unclassifiable). The data were analysed using a two-way analysis of variance with unequal cell sizes. ESR, C4, C1-INH, IgG and CEA varied with the extent of disease. When the data were adjusted for this variation, we found that the values of ESR, C4 and CEA were different between the various histological types. The values were highest in patients with the intestinal-type tumor and lowest in those with diffuse tumor. The concentrations of IgG and C1-INH were not different between the histological types. Our results are relevant when ESR, C4 and CEA are used in the evaluation of patients with gastric carcinoma.

Blood Proteins↗

Recurrent abdominal pain as the sole manifestation of hereditary angioedema in multiple family members.

This paper describes a previously unreported finding of abdominal pain as the only lifelong manifestation of hereditary angioedema in multiple family members. This diagnosis was obscured by the absence of cutaneous, oropharyngeal, and respiratory involvement. Barium studies performed during painful attacks showed transient intestinal wall edema which, along with abnormalities in the C4 level and C1 esterase inhibitor activity, confirmed the diagnosis. It is important that hereditary angioedema be recognized in its various forms so that invasive procedures can be avoided and prophylactic therapy can be administered.

Abdomen↗

Acquired C1 inhibitor deficiency with lymphoma causing recurrent angioedema.

A 52 year old man who developed recurrent, massive and generalized angioedema for the first time during adult life was found to have an acquired deficiency of C1q esterase inhibitor (C1 INH) in association with a B cell lymphoma producing a paraprotein. He had low levels of C4 and C1 INH during the attacks which returned to normal after the successful treatment of lymphoma. An underlying lymphoproliferative disease should always be considered in adult patients with this immunological profile, recurrent angioedema and a negative family history.

Angioedema↗

Synthetic inhibitors of trypsin, plasmin, kallikrein, thrombin, C1r-, and C1 esterase.

p-Carbethoxyphenyl episol-guanidinocaproate and p-(p'-guanidinobenzoyloxy)-phenyl derivatives were prepared, and their inhibitory effects on trypsin, plasmin, plasma kallikrein, thrombin, C1r- and C1 esterase were examined. Among the various inhibitors tested, p-nitrophenyl p'-guanidinobenzoate, N,N-dimethylamino p-(p'-guanidinobenzoyloxy)-benzoyl glycolate and N,N-dimethylamino p-(p'-guanidinobenzoyloxy)-benzilcarbonyloxy glycolate were the most effective inhibitors of trypsin, plasmin, plasma kallikrien and thrombin, and they strongly inhibited the esterolytic activities of C1r- and C1 esterase.

Complement Activating Enzymes↗

Untreated intra-abdominal sepsis: lack of synergism between polymorphonuclear leukocyte (PMN) complement receptors CR1/CR3 and IgG receptor FcRIII.

We have examined the effects of untreated intra-abdominal sepsis on polymorphonuclear leukocyte (PMN) phagocytosis. Phagocytosis was studied in a receptor-specific fashion looking at the interrelationship between FcRIII-, complement receptor (CR1)-, and complement receptor 3 (CR3)-mediated phagocytosis. Twelve swine underwent either sham laparotomy (n = 5) or laparotomy with cecal ligation and incision (n = 7) to induce intra-abdominal sepsis. PMN phagocytosis was assayed on POD 1, 4, and 8. In animals undergoing sham laparotomy, FcRIII-mediated phagocytosis was less than 10% on all days and was augmented with the addition of C3b or C3bi to the target particles (FcR + CR1 or FcR + CR3 greater than FcR alone). In animals undergoing cecal ligation and incision, baseline FcRIII-mediated phagocytosis increased between POD 1 and 4 and fell between POD 4 and 8. No increase in phagocytosis was seen on POD 4 or 8 with the addition of C3b or C3bi to the target particles (FcR + CR1 or FcR + CR3 = FcR alone). Preligation of the FcRIII but not FcRII or FcRI receptor with a monoclonal antibody (3G8) markedly reduced phagocytosis in the animals with intraabdominal sepsis.(ABSTRACT TRUNCATED AT 250 WORDS)

Abscess↗

Replacement therapy in hereditary angioedema: successful treatment of acute episodes of angioedema with partly purified C1 inhibitor.

Although considerable progress has been made during the past two decades in the use of androgens to prevent attacks of hereditary angioedema, replacement of the deficient C1-inhibitor protein would provide a useful menas of treatment once an attack has begun. We studied the clinical use of C1 inhibitor that was partly purified on a large scale from pooled plasma. The in vivo efficacy and safety of this protein concentrate were evaluated during 11 intravenous infusions in eight patients with hereditary angioedema. Three patients received the C1-inhibitor preparation during an asymptomatic period. Increases in serum C4 activity provided evidence of the biologic activity of the infused inhibitor. Intravenous administration of the concentrate during acute abdominal or laryngeal attacks of hereditary angioedema in five patients resulted in abatement of symptoms in addition to increased serum C4 activity. No untoward effects of the intravenous administration of the C1 inhibitor were observed in these eight patients. Thus, this C1-inhibitor preparation seems to offer the potential for safe, effective replacement therapy and may provide a means of controlling an attack of hereditary angioedema that is in progress.

Angioedema↗

[Treatment of hereditary angioneurotic edema with androgens].

Hereditary angioedema (HANE) is a rare, life-threatening disease due to the deficiency of C1 inhibitor (C1 Inh). Androgen therapy has been recently shown to be effective for prophylaxis of Hane attacks. Since life-long androgen therapy may be hazardous, this study was designed to define the minimal doses required for effectiveness. Ten patients from six different families were treated during cumulative 73 months by danazol and/for methandrostenolone. One tablet/day of either drug was the minimal requirement to prevent any attack in all patients. When 3 tablets/day were given, complement abnormalities were simultaneously rapidly reversed. When 1 tablet/day was given the biological effect was barely detectable, except for C2. Serum C2 levels may, therefore, represent the best criteria of androgen therapy effectiveness. Thus, an excellent clinical result can be obtained with much lower doses of androgens than previously stated. This result seemed important with respect to the serious dose-dependent risk of androgens.

Adult↗

Antibody to C1-inhibitor in a patient receiving C1-inhibitor infusions for treatment of hereditary angioneurotic edema with systemic lupus erythematosus reacts with a normal allotype of residue 458 of C1-inhibitor.

Patients with hereditary C4 deficiency are likely to have severe lupus erythematosus. A patient with hereditary angioneurotic edema (HANE) and systemic lupus erythematosus (SLE) had a chronic deficiency in C4 because the hereditary deficiency in C1-inhibitor allowed the C1 in her serum to become activated and then inactivate C4. An attempt was made to repair the C4 deficiency as well as the deficiency in C1-inhibitor by giving infusions of human C1-inhibitor in the hope of inducing remissions of both HANE and SLE. During treatment, antibody to C1-inhibitor developed in the patient; this cleared when the infusions were stopped. During subsequent treatment with danazol alone, measurable C1-inhibitor developed in the patient's serum, but levels of C4 were never significantly increased. Antibody to normal C1-inhibitor was not expected to develop in the patient because she is heterozygous for this autosomal dominant trait. A normal allotype (VAL or MET 458), which would have been in the preparation used but which the patient does not synthesize because she can produce only one allotype (MET 458), appears to have been immunogenic. The antibody isolated from the patient's serum reacted with C1-inhibitor from a normal individual known to be homozygous for 458-VAL but not with one from a homozygote for MET-458.

Adult↗

Increased plasma concentrations of C9, C1-inhibitor and alpha 1-protease inhibitor associated with cigarette smoking.

The association between various parameters of acute and chronic smoking status and plasma levels of three proteins, C9, C1-inhibitor (C1-INH) and alpha 1-protease inhibitor (alpha 1-PI) were determined for 49 male cigarette smokers and 49 age-matched nonsmokers (mean age = 32.2 years). The mean number of cigarettes smoked was 28.7 per day while the cumulative consumption was only 18.1 pack-years. Plasma levels of all three proteins were significantly higher in the smokers than nonsmokers. Plasma C9 and alpha 1-PI concentrations correlated with cumulative cigarette consumption and plasma nicotine concentrations. While C1-INH concentration did not correlate with either cumulative cigarette consumption or plasma nicotine concentration, it correlated significantly with serum thiocyanate concentration. No consistent correlation was found between plasma concentration of these proteins and parameters of pulmonary function.

Adult↗

Mechanism of action of anti-C1-inhibitor autoantibodies: prevention of the formation of stable C1s-C1-inh complexes.

BACKGROUND: Acquired C1-inhibitor (C1-inh) deficiency is usually associated with the presence of circulating C1-inh autoantibodies. These autoantibodies have been shown previously to bind to two synthetic peptides corresponding to C1-inh amino acid residues 438-449 (peptide 2) and 448-459 (peptide 3) but not to peptide 1 (residues 428-440). MATERIALS AND METHODS: Affinity-purified C1-inh autoantibodies from two patients with acquired C1-inh deficiency were studied for their effects on the inhibition of C1s activity by C1-inh using SDS-PAGE and hydrolysis of a synthetic ester. RESULTS: Functional studies confirmed that the anti-C1-inh autoantibodies abrogated C1-inh activity, and their maximum effect was produced when the concentrations of C1-inh and autoantibody were approximately equimolar. The autoantibodies prevent the formation of the C1s-C1-inh complex, but they do not dissociate the preformed complex, suggesting that the autoantibodies act prior to the formation of the enzyme-inhibitor complex. In the presence of autoantibodies, C1s cleaves C1-inh, and a stable covalent bond between C1s and C1-inh does not form. Peptides 2 and 3, but not peptide 1 inhibited autoantibody activity, thus C1-inh inhibitory activity for C1s was expressed fully. CONCLUSIONS: Our data indicate that the anti-C1-inh autoantibodies convert C1-inh to a substrate by preventing the formation of the stable covalent protease-serpin complex. The data also suggest a possible therapeutic use for peptides 2 and 3 or their derivatives in the management of patients with type II acquired angioedema (AAE).

Autoantibodies↗

Expression of functional human C1 inhibitor in COS cells.

Full length human C1 inhibitor cDNA was cloned into a vector suitable for transient expression in COS-1 cells. Transfected COS cells secreted an immunoreactive protein of Mr approximately 110,000 that appeared to be functionally equivalent to the plasma-derived protein as established by the following criteria: 1) ability to form sodium dodecyl sulfate-stable complexes with C1s, factor XIIa, and kallikrein; 2) inhibition of C1s-mediated C4 consumption; and 3) susceptibility to inactivation by the nontarget proteinase elastase. Quantitation of secreted recombinant C1 inhibitor by radioimmunoassay indicated that 72 h after transfection the level was approximately 2.2 micrograms/ml. Treatment of transfected cells with tunicamycin resulted in secretion of a protein of Mr approximately 90,000 that was also capable of complex formation with C1s.

Animals↗

Hereditary angioneurotic edema: clinical and laboratory findings in 58 subjects.

An in-depth analysis of clinical and laboratory findings in 58 patients affected by hereditary angioneurotic edema (HANE) is reported with special focus on problems related to the diagnosis of the disorder. The functional C1 inhibitor (C1INH) assay is the method of choice in the diagnosis of HANE, as it is capable of revealing the disorder with 100% accuracy. The immunochemical assay of C1INH detected HANE in 84.5% of the cases, i.e., immunochemical deficiency of C1INH (type I HANE). C4 was markedly reduced in both type I and type II HANE; thus, C4 levels can be particularly useful when C1INH functional tests are not available. CH50 testing is of little diagnostic value since total hemolytic complement activity is reduced in a variety of other congenital or acquired pathologies involving the complement system. The CH50 assay after incubation in low ionic strength buffer may be utilized in mass screening programs for qualitative evaluation. However, the test has the drawback of not being applicable in cases of frank hypocomplmentemia. While a depletion of the complement classical pathway was detected in most cases, no alteration in the complement alternative pathway was recorded, nor there was any reduction in immunoglobulin levels. Family history was positive in 100% of the cases. Attacks were almost always brought on by stress and/or trauma, though the causes were sometimes unknown. Edema could be cutaneous (non-pitting and non-pruritic) in 94.2%, laryngeal (often life-threatening) in 48% and abdominal (almost always painful) in 88.4% of patients. Associated pathologies were found in 2 patients, i.e., lupus rash and C3NeF-positive chronic membranoproliferative glomerulonephritis, respectively.

Adolescent↗

Hereditary angioedema type II--a study of two families.

Hereditary angioedema (HA) is caused by a quantitative or qualitative deficiency of C1 esterase inhibitor (C1 INH). We present a study of nine patients with HA belonging to two different families. The symptoms started before 10 years of age in most cases (78%). Facial edema (lips, eyes) and of the extremities (feet, hands) were the most frequent complaints. Three patients presented edema of the glottis and one of them underwent a tracheostomy twice. Laboratory tests, outside the acute crisis, revealed low levels of C4 in all patients. The serum levels of C1 INH were normal in seven patients; however, functional activity was not observed in any of them. After the use of a modified androgen (danazol), control of symptoms was observed in all patients, although functional activity was re-established in only five patients.

Adolescent↗

Hereditary angioedema: a study of three families.

Familial angioedema is an autosomal dominant hereditary disease whose pathogenesis is attributed to a C1 inhibitor (C1 INH) deficit. Two genetic forms have been recognized related to the C1 inhibitor deficiency or its dysfunction. Antifibrinolytics as well as androgenic derivatives have proved to be effective in the prevention and treatment of this pathology. In this paper we present the studies carried out in three families affected by C1 inh. deficit and the treatment employed. Some of the members of these families showed symptoms related with this deficit. A satisfactory explanation has not been formulated to justify the reason why only some of the members in our study showed symptomatology, given that there were no differences between the C1 inh. levels in these patients and those who were not affected. The absence of family history connected with this disease does not necessarily suggest that a genetic mutation has been produced. This deficit could have been present in earlier generations but without clinical manifestations. Stanozolol proved effective in the control of symptoms in the two patients to whom this treatment was applied. However, the rise of C1 inh. levels was significative only in one of them. The lack of connection between the clinical improvement and the normalization of the C1 inh. levels led us to think that the main goal of the therapy should not be directed to the normalization of these levels but to keep the patient asymptomatic with the lowest possible doses of the selected medication.

Adult↗

Postburn edema and related changes in interleukin-2, leukocytes, platelet activation, endothelin-1, and C1 esterase inhibitor.

Interleukin-2 (IL-2) promotes multisystem organ edema, lung neutrophil sequestration, and platelet activation through alterations in the microvascular barriers and permeability. IL-2, complement, platelet, and vascular endothelial activation were evaluated in 60 patients. One-factor analysis of variance indicated a significantly increased absolute neutrophil count on day 1 (p < 0.0001) and decreased C1Inh, p = 0.0001, with elevated IL-2 levels in the 20% to 40% group (p = 0.008). Endothelin-1 levels were significantly increased in the 20% to 40% total body surface area group on day 5. The absolute neutrophil count was significantly reduced in both groups, and C1Inh rose to near normal levels by day 5. No significant elevations of 6-keto prostaglandin F1 alpha were observed on day 1 or day 5 in the < 40% total body surface area group; however, these levels were significantly elevated on day 1 in the > 40% total body surface area group. Thromboxane B2 and platelet factor 4 were significantly elevated in all groups (p = 0.001) on days 1 and 5. Regression analysis implicated infection as a significant contributor to the IL-2 variations (r2 = 0.61), with inhalation injury minimally affecting IL-2 plasma levels (r2 = 0.09). Generalized edema increased with increasing burn wound size in parallel with elevated IL-2 and endothelin-1 levels, reduced C1Inh levels, and leukocytosis in the first week after thermal injury. These data suggest that there are dynamic interactions among the endothelium, cytokine stimulation, leukocytosis, complement, and platelet activation in promoting the microvascular permeability.

Adolescent↗

Hereditary angioedema: a family study.

Hereditary angioedema (HAE) is a rare, life-threatening, autosomal dominant disease characterized by recurrent episodes of angioedema, and caused by a deficiency of the plasma protein C1-esterase inhibitor (C1-INH). Clinical manifestation of HAE may first develop during childhood but typically presents around puberty with nonpruritic and non-pitting edema of the subcutaneous and mucosal tissues. Up to now, there has been no published report of HAE case in Taiwan. We reported a 33 year-old female patient who had recurrent painful swelling of face and hands since 27 years of age. She first suffered from sudden onset of painful swelling of the eyelids and lips in August 1998 when she was pregnant for the first time. Subsequently, similar episodes recurred for a few times. Her blood test disclosed that her C3 and C4 were 125 mg/dl and 6 mg/dl, respectively. Her uncle died of laryngeal edema at the age of 30 years. Her father and elder brother also had the similar history of recurrent facial and hand swelling. The C4 levels of her elder brother were 6 mg/dl and 13.3 mg/dl on two separate occasions. The C1-INH antigen serum level and functional assay of the index patient and ten other family members were studied. A total of seven members of the family were confirmed to have type 1 HAE as evidenced by the low C4 and low C1-INH antigenic level and functional activity. Two of the seven cases were asymptomatic up to the date of our report.

Adult↗

Cleavage and inactivation of human C1 inhibitor by the human leukocyte proteinase, proteinase 3.

Incubation of highly purified human C1 inhibitor with equally pure human leukocyte proteinase 3, resulted in a dose- and time-dependent inactivation of C1 inhibitor hemolytic activity. Furthermore, this inactivation was accompanied by proteinase 3-dependent cleavage of the C1 inhibitor into an 83,000 molecular weight fragment. The formation of the 83,000 molecular weight fragment followed a time course which was similar to that observed for the inactivation of hemolytic activity. Within 120 minutes more than 90% of the hemolytic activity was lost. This inactivation of C1 inhibitor appeared to be selective as purified human C1q was not degraded in a similar time period. Moreover, when 100 micrograms IgG, isolated from each of 21 Wegener's granulomatosis patients with cytoplasmic anti-nuclear antibodies immunofluorescent titers to proteinase 3 greater then 1:64, was incubated with 3 milliunits of proteinase 3, little to no cleavage of C1 inhibitor was observed. In contrast, 100 micrograms of IgG isolated from 14 normal donors was ineffective in affording protection to C1 inhibitor upon incubation with proteinase 3. Our results suggest that neutrophil infiltration and activation could lead to local complement consumption at the tissue sites.

Antibodies, Antineutrophil Cytoplasmic↗