Hemodialysis with cellulosic membranes results in both complement and granulocyte activation. We investigated the effects of soluble complement receptor 1 (sCR1), a potent complement inhibitor, on both complement and granulocyte activation in an ex vivo model of dialysis. Measurements were made of complement activation (radioimmunoassay for C3a desArg) as well as granulocyte activation (flow cytometric measurements of reactive oxygen species production, granulocyte CD11b/CD18 (MAC-1) expression and CD62L (L-selectin) expression). sCR1 completely abolished the generation of plasma C3a desArg during ex vivo hemodialysis. Without sCR1, C3a desArg levels rose from 968 +/- 373 ng/ml to 4961 +/- 40 ng/ml by the end of the ex vivo procedure (p < 0.001). sCR1 also completely inhibited MAC-1 upregulation and L-selectin shedding from granulocytes during ex vivo hemodialysis. With sCR1 there was still a statistically significant increase in granulocyte reactive oxygen species production (from 2.42 +/- 0.1 fluorescence channels to 6.47 +/- 0.7 fluorescence channels, p < 0.01) but a 50% inhibition when compared with experiments without sCR1 (3.15 +/- 0.5 to 11.2 +/- 1.9, p < 0.01). We conclude that sCR1 completely abolishes complement activation and changes in granulocyte cell adhesion molecules during ex vivo hemodialysis with cellulosic membranes. sCR1 partially inhibits granulocyte reactive oxygen species formation.
{"title":"Soluble complement receptor 1 inhibits both complement and granulocyte activation during ex vivo hemodialysis.","authors":"J Himmelfarb, E McMonagle, D Holbrook, C Toth","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Hemodialysis with cellulosic membranes results in both complement and granulocyte activation. We investigated the effects of soluble complement receptor 1 (sCR1), a potent complement inhibitor, on both complement and granulocyte activation in an ex vivo model of dialysis. Measurements were made of complement activation (radioimmunoassay for C3a desArg) as well as granulocyte activation (flow cytometric measurements of reactive oxygen species production, granulocyte CD11b/CD18 (MAC-1) expression and CD62L (L-selectin) expression). sCR1 completely abolished the generation of plasma C3a desArg during ex vivo hemodialysis. Without sCR1, C3a desArg levels rose from 968 +/- 373 ng/ml to 4961 +/- 40 ng/ml by the end of the ex vivo procedure (p < 0.001). sCR1 also completely inhibited MAC-1 upregulation and L-selectin shedding from granulocytes during ex vivo hemodialysis. With sCR1 there was still a statistically significant increase in granulocyte reactive oxygen species production (from 2.42 +/- 0.1 fluorescence channels to 6.47 +/- 0.7 fluorescence channels, p < 0.01) but a 50% inhibition when compared with experiments without sCR1 (3.15 +/- 0.5 to 11.2 +/- 1.9, p < 0.01). We conclude that sCR1 completely abolishes complement activation and changes in granulocyte cell adhesion molecules during ex vivo hemodialysis with cellulosic membranes. sCR1 partially inhibits granulocyte reactive oxygen species formation.</p>","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"126 4","pages":"392-400"},"PeriodicalIF":0.0,"publicationDate":"1995-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18568085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Genetic factors in the development of diabetic nephropathy.","authors":"R Trevisan, G Viberti","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"126 4","pages":"342-9"},"PeriodicalIF":0.0,"publicationDate":"1995-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18568077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T J Morgan, Z H Endre, D M Kanowski, L I Worthley, R D Jones
The p50 and derived indexes, calculated by using the Siggaard-Andersen algorithm from a single measurement of arterial blood gas tensions and hemoglobin-oxygen saturation, are used to assess tissue oxygen availability in critical illness. We tested the accuracy of the Siggaard-Andersen p50 algorithm over a wide range of pathophysiologic conditions. Blood gases, cooximetry, and calculation of standard and in vivo p50 were performed at multiple saturations, CO2 tensions, and H+ concentrations on blood with normal (standard p50 of 26.1 and 26.7 mm Hg), increased (19.0 and 25.4), and reduced (33.9 and 38.2) hemoglobin-oxygen affinity, as well as on high-affinity blood from two patients with diabetic ketoacidosis (16.7 and 20.8). Log p50 in vivo/pH plots were constructed to determine the Bohr effect. Except in the normal affinity specimens (coefficient of variation < 1.7%), standard p50 values showed high variability (coefficient of variation > 5.9%), with saturation-linked bias and distortion of the Bohr effect. Standard p50 was overestimated by up to 11 mm Hg as saturation approached 97%. Although base deficit correction of the stored specimens (6.9 < pH < 7.1) restored the Bohr effect and improved the accuracy of standard p50 calculations (coefficient of variation = 4.4% and 2.9%), saturation-linked bias persisted. We conclude that Siggaard-Andersen p50 calculations may be misleading when there are disturbances of hemoglobin-oxygen affinity and acid-base balance, owing to changes in shape of the hemoglobin-dissociation curve. When metabolic acidosis occurs with high hemoglobin-oxygen affinity, as can occur in critical illness, indexes derived by the Siggaard-Andersen algorithm on arterial blood may greatly overestimate oxygen availability.
{"title":"Siggaard-Andersen algorithm-derived p50 parameters: perturbation by abnormal hemoglobin-oxygen affinity and acid-base disturbances.","authors":"T J Morgan, Z H Endre, D M Kanowski, L I Worthley, R D Jones","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The p50 and derived indexes, calculated by using the Siggaard-Andersen algorithm from a single measurement of arterial blood gas tensions and hemoglobin-oxygen saturation, are used to assess tissue oxygen availability in critical illness. We tested the accuracy of the Siggaard-Andersen p50 algorithm over a wide range of pathophysiologic conditions. Blood gases, cooximetry, and calculation of standard and in vivo p50 were performed at multiple saturations, CO2 tensions, and H+ concentrations on blood with normal (standard p50 of 26.1 and 26.7 mm Hg), increased (19.0 and 25.4), and reduced (33.9 and 38.2) hemoglobin-oxygen affinity, as well as on high-affinity blood from two patients with diabetic ketoacidosis (16.7 and 20.8). Log p50 in vivo/pH plots were constructed to determine the Bohr effect. Except in the normal affinity specimens (coefficient of variation < 1.7%), standard p50 values showed high variability (coefficient of variation > 5.9%), with saturation-linked bias and distortion of the Bohr effect. Standard p50 was overestimated by up to 11 mm Hg as saturation approached 97%. Although base deficit correction of the stored specimens (6.9 < pH < 7.1) restored the Bohr effect and improved the accuracy of standard p50 calculations (coefficient of variation = 4.4% and 2.9%), saturation-linked bias persisted. We conclude that Siggaard-Andersen p50 calculations may be misleading when there are disturbances of hemoglobin-oxygen affinity and acid-base balance, owing to changes in shape of the hemoglobin-dissociation curve. When metabolic acidosis occurs with high hemoglobin-oxygen affinity, as can occur in critical illness, indexes derived by the Siggaard-Andersen algorithm on arterial blood may greatly overestimate oxygen availability.</p>","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"126 4","pages":"365-72"},"PeriodicalIF":0.0,"publicationDate":"1995-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18568081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
It has been suggested that herbs of the Phyllanthus family may have antiviral activity. We therefore tested the effects of three different Phyllanthus extracts on the serologic status of 123 patients with chronic hepatitis B. Eleven patients received an extract of Phyllanthus amarus (L) provided by S.P. Thyagarajan, Madras, India. Forty-two patients received Phyllanthus niruri (L), gathered from Hainan Province in China, and 35 patients received an extract of Phyllanthus urinaria (L), which had been gathered in Henan Province. Thirty-five control patients received no herbal therapy. The patients receiving Phyllanthus urinaria (L) were both more likely to lose detectable hepatitis B e-antigen from their serum and more likely to seroconvert hepatitis B e-antibody status from negative to positive than were patients given either of the other two preparations. No patient changed status with respect to hepatitis B s-antigen.
{"title":"Herbs of the genus Phyllanthus in the treatment of chronic hepatitis B: observations with three preparations from different geographic sites.","authors":"M Wang, H Cheng, Y Li, L Meng, G Zhao, K Mai","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>It has been suggested that herbs of the Phyllanthus family may have antiviral activity. We therefore tested the effects of three different Phyllanthus extracts on the serologic status of 123 patients with chronic hepatitis B. Eleven patients received an extract of Phyllanthus amarus (L) provided by S.P. Thyagarajan, Madras, India. Forty-two patients received Phyllanthus niruri (L), gathered from Hainan Province in China, and 35 patients received an extract of Phyllanthus urinaria (L), which had been gathered in Henan Province. Thirty-five control patients received no herbal therapy. The patients receiving Phyllanthus urinaria (L) were both more likely to lose detectable hepatitis B e-antigen from their serum and more likely to seroconvert hepatitis B e-antibody status from negative to positive than were patients given either of the other two preparations. No patient changed status with respect to hepatitis B s-antigen.</p>","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"126 4","pages":"350-2"},"PeriodicalIF":0.0,"publicationDate":"1995-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18568078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mucosal epithelial cell preparations from 18 disease-free segments of human colon resections and 7 cell lines were examined for chemoattractant properties. Mucosal cells were dissociated from lamina propria by sequential incubations in ethylenediaminetetraacetic acid, harvested at 1.5 x 10(6) cells/ml, and lysed. Lysates were tested for chemoattractant activity for monocytes and neutrophils. Chemoattractant preparations were further purified by gel filtration chromatography, and amino acid analysis was performed on selected chemoattractant fractions. Mucosa from normal bowel exhibited significant chemoattractant properties for monocytes, up to 15 times greater than for neutrophils. Checkerboard analysis indicated chemotaxis rather than chemokinesis. Neither cell culture nor lamina propria cell lysates exhibited statistically significant chemoattraction, although activity was evident in certain preparations of isolated cell cultures. Chromatography of human mucosal chemoattractant preparations consistently gave peaks of activity in the 2000 dalton range. These yielded consistent amino acid profiles, with aspartic acid, glutamic acid, glycine, alanine, and lysine being dominant in all preparations. This peptide is apparently different from other known chemotactic agents and could play a role in recruitment of mononuclear phagocytes to the mucosa of the human colon.
从人结肠切除的18个无病段和7个细胞系制备的粘膜上皮细胞进行了化学引诱特性的检测。粘膜细胞在乙二胺四乙酸中连续孵育,从固有层分离,以1.5 x 10(6)个细胞/ml的速度收获,并裂解。测定裂解物对单核细胞和中性粒细胞的化学引诱活性。通过凝胶过滤层析进一步纯化化学引诱剂制剂,并对选定的化学引诱剂组分进行氨基酸分析。正常肠粘膜对单核细胞表现出显著的化学引诱特性,比中性粒细胞强15倍。棋盘分析显示趋化性而非趋化运动。细胞培养物和固有层细胞裂解物都没有表现出统计学上显著的化学吸引力,尽管活性在某些分离细胞培养物的制备中是明显的。人粘膜化学引诱剂制剂的色谱一致给出活性峰在2000道尔顿范围内。这些结果产生了一致的氨基酸谱,天冬氨酸、谷氨酸、甘氨酸、丙氨酸和赖氨酸在所有制剂中占主导地位。这种肽明显不同于其他已知的趋化剂,可能在单核吞噬细胞募集到人结肠粘膜中发挥作用。
{"title":"Monocyte chemoattractant activity associated with human colon mucosal cells.","authors":"W Beeken, J Bigelow, J Fabian","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Mucosal epithelial cell preparations from 18 disease-free segments of human colon resections and 7 cell lines were examined for chemoattractant properties. Mucosal cells were dissociated from lamina propria by sequential incubations in ethylenediaminetetraacetic acid, harvested at 1.5 x 10(6) cells/ml, and lysed. Lysates were tested for chemoattractant activity for monocytes and neutrophils. Chemoattractant preparations were further purified by gel filtration chromatography, and amino acid analysis was performed on selected chemoattractant fractions. Mucosa from normal bowel exhibited significant chemoattractant properties for monocytes, up to 15 times greater than for neutrophils. Checkerboard analysis indicated chemotaxis rather than chemokinesis. Neither cell culture nor lamina propria cell lysates exhibited statistically significant chemoattraction, although activity was evident in certain preparations of isolated cell cultures. Chromatography of human mucosal chemoattractant preparations consistently gave peaks of activity in the 2000 dalton range. These yielded consistent amino acid profiles, with aspartic acid, glutamic acid, glycine, alanine, and lysine being dominant in all preparations. This peptide is apparently different from other known chemotactic agents and could play a role in recruitment of mononuclear phagocytes to the mucosa of the human colon.</p>","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"126 4","pages":"358-64"},"PeriodicalIF":0.0,"publicationDate":"1995-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18568080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D Mohanty, H al Hassan, P Neglen, B Eklof, K C Das
{"title":"Protein C deficiency in Kuwait.","authors":"D Mohanty, H al Hassan, P Neglen, B Eklof, K C Das","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"126 4","pages":"373-6"},"PeriodicalIF":0.0,"publicationDate":"1995-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18568082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Desmopressin (1-desamino-8-D-arginine vasopressin (DDAVP)) is a synthetic analog of arginine vasopressin (AVP) and is useful in the treatment of some bleeding disorders. The mechanism of improved hemostasis in patients with platelet dysfunction is uncertain. Platelet-rich plasma samples from 35 normal subjects were incubated with serial dilutions of DDAVP, AVP, and adenosine diphosphate. The expression of the platelet activation-dependent antigen CD62 (P-selectin) was measured by fluorescent-labeled monoclonal antibody and flow cytometry. DDAVP at concentrations of 1.0 to 1000 nmol/L stimulated significant expression of CD62 on normal platelets in vitro. At a pharmacologic concentration of DDAVP (1 nmol/L), 14.1% (0.6% to 45.4%) (median and range) of platelets expressed CD62. There was a strong correlation between DDAVP-induced and AVP-induced CD62 expression (rs = 0.62, p = 0.0008) but not between DDAVP-induced and ADP-induced expression, suggesting a V1 receptor-mediated mechanism. Preincubation of platelets with a vasopressin V1 receptor antagonist completely inhibited CD62 expression in response to DDAVP. We conclude that DDAVP directly activates platelets by interaction with the platelet V1 receptor in vitro. This finding may partially explain in vivo effects of DDAVP on hemostasis.
去氨加压素(1-去氨氨基-8- d -精氨酸加压素(DDAVP))是精氨酸加压素(AVP)的合成类似物,可用于治疗一些出血性疾病。血小板功能障碍患者改善止血的机制尚不清楚。35名正常受试者的富血小板血浆样本在连续稀释DDAVP、AVP和二磷酸腺苷的条件下孵育。采用荧光标记单克隆抗体和流式细胞术检测血小板活化依赖性抗原CD62 (p -选择素)的表达。1.0 ~ 1000 nmol/L浓度的DDAVP可刺激正常血小板上CD62的显著表达。在DDAVP药理学浓度(1 nmol/L)下,14.1%(0.6% ~ 45.4%)的血小板表达CD62(中位数和范围)。ddavp诱导的CD62表达与avp诱导的CD62表达之间有很强的相关性(rs = 0.62, p = 0.0008),但ddavp诱导的CD62表达与adp诱导的CD62表达之间没有相关性,提示其可能存在V1受体介导的机制。血小板与抗利尿激素V1受体拮抗剂的预孵育完全抑制CD62的表达,以响应DDAVP。我们得出结论,在体外,DDAVP通过与血小板V1受体相互作用直接激活血小板。这一发现可以部分解释davp在体内对止血的作用。
{"title":"Desmopressin stimulates the expression of P-selectin on human platelets in vitro.","authors":"T Wun, T G Paglieroni, N A Lachant","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Desmopressin (1-desamino-8-D-arginine vasopressin (DDAVP)) is a synthetic analog of arginine vasopressin (AVP) and is useful in the treatment of some bleeding disorders. The mechanism of improved hemostasis in patients with platelet dysfunction is uncertain. Platelet-rich plasma samples from 35 normal subjects were incubated with serial dilutions of DDAVP, AVP, and adenosine diphosphate. The expression of the platelet activation-dependent antigen CD62 (P-selectin) was measured by fluorescent-labeled monoclonal antibody and flow cytometry. DDAVP at concentrations of 1.0 to 1000 nmol/L stimulated significant expression of CD62 on normal platelets in vitro. At a pharmacologic concentration of DDAVP (1 nmol/L), 14.1% (0.6% to 45.4%) (median and range) of platelets expressed CD62. There was a strong correlation between DDAVP-induced and AVP-induced CD62 expression (rs = 0.62, p = 0.0008) but not between DDAVP-induced and ADP-induced expression, suggesting a V1 receptor-mediated mechanism. Preincubation of platelets with a vasopressin V1 receptor antagonist completely inhibited CD62 expression in response to DDAVP. We conclude that DDAVP directly activates platelets by interaction with the platelet V1 receptor in vitro. This finding may partially explain in vivo effects of DDAVP on hemostasis.</p>","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"126 4","pages":"401-9"},"PeriodicalIF":0.0,"publicationDate":"1995-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18568654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M de Haas, P J Vossebeld, A E von dem Borne, D Roos
{"title":"Fc gamma receptors of phagocytes.","authors":"M de Haas, P J Vossebeld, A E von dem Borne, D Roos","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"126 4","pages":"330-41"},"PeriodicalIF":0.0,"publicationDate":"1995-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18567632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
To determine the effects of therapeutic interventions on plasma protein concentrations, it is often desirable to rule out nonspecific effects of hemodilution. Because red cells are restricted to the vascular space, the hematocrit (Hct) is a convenient marker. At the bedside--and even in scientific reports--a simple ratio of Hcts (obtained before and after the change in plasma volume) is often used to "correct" the value of interest. This is incorrect, and it may introduce a sizeable error. A new method, the plasma dilution factor (PDF), has been mathematically deduced. It accounts for the influence of any blood loss, plasma osmolality changes, and blood volume variations on plasma and serum concentrations. In an in vitro experiment, blood loss and osmolality and blood volume changes were simulated through the withdrawal of various volumes of blood, which were replaced with smaller, identical, or larger volumes of hypotonic, isotonic, or hypertonic solutions. The PDF accurately predicted changes in concentrations of albumin, fibrinogen, and antithrombin III. In contrast, the Hct ratio significantly underestimated the effects of dilution. Von Willebrand factor concentrations after hemodilution through dextran infusion in volunteers were the same as predicted by the PDF. In patients undergoing orthopedic surgery who were also given dextran, the postdilution von Willebrand factor concentrations were higher than predicted by the PDF. The Hct gave a false impression of a decrease in the volunteers that was not explained by hemodilution, and it failed to detect the von Willebrand factor response to trauma in the surgical patients.(ABSTRACT TRUNCATED AT 250 WORDS)
{"title":"The plasma dilution factor: predicting how concentrations in plasma and serum are affected by blood volume variations and blood loss.","authors":"A Flordal","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>To determine the effects of therapeutic interventions on plasma protein concentrations, it is often desirable to rule out nonspecific effects of hemodilution. Because red cells are restricted to the vascular space, the hematocrit (Hct) is a convenient marker. At the bedside--and even in scientific reports--a simple ratio of Hcts (obtained before and after the change in plasma volume) is often used to \"correct\" the value of interest. This is incorrect, and it may introduce a sizeable error. A new method, the plasma dilution factor (PDF), has been mathematically deduced. It accounts for the influence of any blood loss, plasma osmolality changes, and blood volume variations on plasma and serum concentrations. In an in vitro experiment, blood loss and osmolality and blood volume changes were simulated through the withdrawal of various volumes of blood, which were replaced with smaller, identical, or larger volumes of hypotonic, isotonic, or hypertonic solutions. The PDF accurately predicted changes in concentrations of albumin, fibrinogen, and antithrombin III. In contrast, the Hct ratio significantly underestimated the effects of dilution. Von Willebrand factor concentrations after hemodilution through dextran infusion in volunteers were the same as predicted by the PDF. In patients undergoing orthopedic surgery who were also given dextran, the postdilution von Willebrand factor concentrations were higher than predicted by the PDF. The Hct gave a false impression of a decrease in the volunteers that was not explained by hemodilution, and it failed to detect the von Willebrand factor response to trauma in the surgical patients.(ABSTRACT TRUNCATED AT 250 WORDS)</p>","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"126 4","pages":"353-7"},"PeriodicalIF":0.0,"publicationDate":"1995-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18568079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The role of gastric mucus was evaluated in a rat model of gastric epithelial damage induced by local ischemia/reperfusion (I/R) stress. In this model, blood-to-lumen chromium 51-labeled ethylenediaminetetraacetic acid (51Cr-EDTA) clearance served as an index of injury. Tetraprenyl acetone (TPA; 100 mg, 200 mg/kg IP) was used to stimulate mucus production. Administration of TPA increased both the hexosamine content in gastric tissue and the amount of alcian blue-periodic acid Schiff (AB-PAS) stained mucus in the mucosa in a dose-dependent manner. Increases in 51Cr-EDTA clearance induced by I/R were significantly attenuated by TPA in a dose-dependent manner. N-acetyl-L-cysteine (NAC; 0.6%, 0.8%) was perfused into the gastric lumen to assess the effect of reduction in mucus on the injury induced by I/R. Although mean values of hexosamine content were increased by perfusion with NAC, AB-PAS-stained mucus in the mucosa was significantly decreased in a dose-dependent manner. Perfusion of NAC did not change basal 51Cr-EDTA clearance but significantly exacerbated the increase in clearance induced by I/R in a dose-dependent manner. These results indicate that gastric mucus protects the gastric mucosa against I/R stress in vivo.
{"title":"Role of mucus in gastric mucosal injury induced by local ischemia/reperfusion.","authors":"K Seno, T Joh, Y Yokoyama, M Itoh","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The role of gastric mucus was evaluated in a rat model of gastric epithelial damage induced by local ischemia/reperfusion (I/R) stress. In this model, blood-to-lumen chromium 51-labeled ethylenediaminetetraacetic acid (51Cr-EDTA) clearance served as an index of injury. Tetraprenyl acetone (TPA; 100 mg, 200 mg/kg IP) was used to stimulate mucus production. Administration of TPA increased both the hexosamine content in gastric tissue and the amount of alcian blue-periodic acid Schiff (AB-PAS) stained mucus in the mucosa in a dose-dependent manner. Increases in 51Cr-EDTA clearance induced by I/R were significantly attenuated by TPA in a dose-dependent manner. N-acetyl-L-cysteine (NAC; 0.6%, 0.8%) was perfused into the gastric lumen to assess the effect of reduction in mucus on the injury induced by I/R. Although mean values of hexosamine content were increased by perfusion with NAC, AB-PAS-stained mucus in the mucosa was significantly decreased in a dose-dependent manner. Perfusion of NAC did not change basal 51Cr-EDTA clearance but significantly exacerbated the increase in clearance induced by I/R in a dose-dependent manner. These results indicate that gastric mucus protects the gastric mucosa against I/R stress in vivo.</p>","PeriodicalId":23085,"journal":{"name":"The Journal of laboratory and clinical medicine","volume":"126 3","pages":"287-93"},"PeriodicalIF":0.0,"publicationDate":"1995-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18669899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}