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At least 595 records · Page 33Linked to original sources
PubMed1990

Preliminary report: effects of interleukin-1 on platelet counts.

Recombinant human interleukin-1 beta was given in 5 daily intravenous infusions to ten patients with metastatic malignant disorders as part of an antineoplastic trial. All ten patients experienced transient increases in heart rate, low-grade fevers, and rigors. A neutrophil-dominated 100% rise in leucocyte counts occurred 4-8 h after treatment. Leucocyte counts returned to baseline levels within 24 h of interleukin-1 beta infusion. A 50% rise in platelets occurred in response to interleukin-1 beta; the increase in platelet counts was first noted 6 days after treatment began and was sustained for 24 days after treatment. Interleukin-1 beta may therefore be beneficial in the treatment of conditions of thrombocytopenia associated with haematological disorders and chemotherapy for malignant disorders.

Adult↗
PubMed1980

Smear platelet counts.

The average number of platelets per oil immersion field, in a count of ten oil fields, multiplied by 20,000 has proved to be a reliable estimation of platelets in normal and thrombocytopenic states. In the presence of thrombocytosis, ie, 25 or more platelets per oil immersion field, the smear count is less reliable. The multiplication factor of 20,000 was determined after statistical analysis of 288 consecutive unselected patients. Certain precautions should be observed, such as use of a fresh EDTA sample or freely flowing finger blood, a well made and well stained smear without platelet aggregates or precipitated stain particles, and an acceptable counting area on the film.

Blood Specimen Collection↗
PubMed1997

[Responses to surgical stress in blood coagulation and fibrinolysis, platelet counts and thromboxane B2 after esophageal cancer operation].

Studies on responses to surgical stress in blood coagulation and fibrinolysis, platelet counts and thromboxane B2 (TXB2) were carried out with 18 esophageal cancer patients who had undergone radical esophagectomy through right thoracotomy and reconstruction with gastric tube. Plasma levels were measured for the following for coagulation assessment: thrombin.antithrombin III complex (TAT), soluble fibrin monomer complex(SFMC), fibrinogen, antithrombin III, protein C and thrombomodulin. Selected fibrinolytic markers are: tissue plasminogen activator.plasminogen activator inhibitor 1 complex (tPA.PAI1C), plasminogen, alpha 2 plasmin inhibitor, plasmin. alpha 2 plasmin inhibitor complex(PIC), FDP and D-dimer. Peripheral venous blood samples were taken from the patients before the operation, immediately after the operation and on each of the first, second, third, seventh and fourteenth day after the operation. It was observed that TAT, SFMC, tPA.PAI-1C and TXB2 were remarkably altered immediately after the operation. This indicates that the major surgical stress significantly activated coagulation, fibrinolysis and platelets. Higher plasma levels of TAT compared to the pre-operation level was recorded for two weeks after the operation. Furthermore, in four cases, SFMC became positive during three to seven days after operation. These facts indicate that the activation of coagulation persisted during the days after operation. PIC began to increase from the 2nd to 3rd days after operation, reaching the maximum on the 7th day. Biphasic changes which peaked twice on the 1st and 7th days after operation were shown in plasma levels of FDP and D-dimer. These results indicate that the activation of fibrinolysis also persisted during the days after operation. The activation of coagulation and fibrinolysis may persist at least for two weeks after major surgical operation. Careful observation for the states of these systems was thought to be needed during the post-operative days, and the molecular markers could be useful to assess subclinical changes of these systems.

Adult↗
PubMed1980

Whole-blood platelet counts with an impedance-type particle counter.

The Clay-Adams Ultra-Flo 100 whole-blood platelet counter provides results that are accurate and precise for platelet counts greater than 20 x 10(9) per liter with virtually zero carryover from one specimen to the next. Comparison of results with those obtained by manual reference and Technicon Autocounter methods shows excellent correlation. The advantage of the Ultra-Flo 100 over the Technicon Autocounter lies in a smaller space requirement in the laboratory, a short start-up time, and minimal maintenance. This makes the Ultra-Flo 100 especially ideal for the stat laboratory. Operating costs of the Ultra-Flo 100 are comparable to those of other methods investigated, but rapid speed of operation has a significant effect on turnaround time.

Humans↗
PubMed2002

[A report of fourteen cases with hemolysis, elevated liver enzymes and low platelet count syndrome].

OBJECTIVE: To summarize the incidence, diagnosis, treatment and prognosis of patients with hemolysis, elevated liver enzymes and low platelet count (HELLP) syndrome. METHODS: The clinical data of fourteen cases with HELLP syndrome complicated by severe pregnancy-induced hypertension were analyzed retrospectively during the past seven years. RESULTS: The incidence of HELLP syndrome was 8% in the patients with severe pregnancy-induced hypertension. According to the diagnosis criteria used by Tennessee University, there were eight cases with complete HELLP syndrome and six cases with partial HELLP syndrome. The major therapeutic way were intensive maternal and fetal monitoring, active management of preeclampsia and eclampsia, administration of corticosteroids and termination the pregnancy as fast as possible. The major complications were DIC, placental abruption, pneumonedema and acute renal failure. The maternal and perinatal mortality were 7% and 29%, respectively. CONCLUSIONS: HELLP syndrome was a serious life-threatening complication of severe pregnancy-induced hypertension. In order to decrease the maternal and perinatal mortality rate, HELLP syndrome should be diagnosed and treated as fast as possible.

Adult↗
PubMed1985

Simultaneous reticulocyte and platelet counting on a clinical flow cytometer.

Laser flow cytometric analysis is well suited to many clinical immunofluorescent and hematologic applications. One of these is automated reticulocyte and platelet enumerations. We have performed a clinical evaluation of a fluorescence laser flow cytometer reticulocyte and platelet enumeration method using the fluorochrome acridine orange. One hundred and thirty-two clinical specimens from inpatients in our comprehensive cancer center were analyzed for platelet counts and 101 samples from the same population were analyzed for reticulocyte counts by the flow cytometer and simultaneously by conventional techniques. Both the reticulocyte and platelet enumerations achieved a high degree of correlation with standard methods for the nonbone marrow-transplant patients studied (R = .989 for reticulocytes and R = .995 for platelets). Marrow transplant patients had a slightly poorer correlation coefficient for the reticulocyte enumeration (R = .923), but analysis of serial determinations of these patients' samples for reticulocyte counts revealed that results were more consistent over time with the automated method than with the traditional manual method. The laser flow cytometer fluorescence reticulocyte and platelet enumeration methods described are efficient, rapid, and reliable for platelet and reticulocyte counting.

Acridine Orange↗
PubMed1977

Metoprolol and the peripheral platelet count.

An acute oral administration of 50 mg metoprolol (a selective beta-1-receptor antagonist) to 18 healthy volunteers induced a significant increase in the peripheral platelet concentration lasting more than 4 h. It is suggested that this increment in the platelet count originates from the exchangeable splenic platelet pool. The mechanism by which metoprolol exerts its effect remains to be established.

Administration, Oral↗
PubMed1989

An efficient procedure for manual platelet counting.

Blood samples were collected by jugular venipuncture from 15 dairy heifers and the blood platelets were counted by manual methods. The platelets were found to be uniformly distributed across the rows, columns and sides of a Neubauer haemocytometer, and it was shown that counting any 10 squares on either side of the haemocytometer and multiplying by a constant factor would accurately predict the total platelet count. This procedure would greatly reduce the time required to count large numbers of platelets per sample, and reduce errors due to the fatigue associated with counting large numbers of samples.

Animals↗
PubMed1981

Effects of exchange transfusion on platelet counts.

With the purpose of knowing to what extent thrombocytopenia that occurs in exchange transfusion (ET) can be secondary to the procedure itself or to a generalized infection, blood counts were made in 42 neonates with hyperbilirubinemia due to maternal fetal isoimmunization of the ABO system. Platelets were quantified halfway and immediately after the exchange transfusion procedure as well as 8, 16, 24, 48 and 72 hours after. It was found that prior to ET platelet levels in donor and patient blood was similar and platelet counts were never under 100,000 mm3 (thrombocytopenia). Halfway and at the conclusion of ET, as well as 8 and 16 hours after, a decrease in platelet levels was observed. After 24 hours an increase was observed that reached basal levels prior to ET after 72 hours. In five children thrombocytopenia was observed; in two, halfway of the ET procedure, in one at the end and two more at 8 and 16 hours after ET. From results obtained we can conclude that thrombocytopenia occurring 24 hours after ET can be due to septicemia.

ABO Blood-Group System↗
PubMed1983

The effects of continuous infusions of prostacyclin-Na (epoprostenol-sodium) on platelet counts, ADP-induced aggregation, and cyclic AMP levels in normal volunteers.

Six male volunteers received either 0 (buffer), 2.5 or 5.0 ng/kg/min PGI2 X Na for 72 hrs. Various platelet parameters were monitored for an additional 72 hrs. Each morning, for seven consecutive days, and +1 and +6 hrs after the termination of the infusion, blood was drawn and platelet rich plasma (PRP) was prepared. The PRP was immediately exposed to 100 ng/ml PGI2 X Na, and the subsequent increase in platelet cyclic AMP was measured by radioimmunoassay. Aggregation in response to 2 or 4 microM ADP was measured simultaneously. Three volunteers returned for a second 72 hr infusion of 5.0 ng/kg/min PGI2 X Na. After 72 hrs, the infusion rate was gradually "tapered off" over a 12 hr period at which time the infusion was terminated. The sensitivity of the PRP to ADP-induced aggregation was recorded before, during, and after the "tapering off" regimen. Platelet counts were not altered by any of the infusions. The responsiveness of the platelet adenylate cyclase to exogenous PGI2 X Na was inversely related to the concentration of PGI2 X Na infused. Desensitization occurred and was more severe after 72 hrs of infusion than after either 24 or 48 hrs. For example, after 72 hrs at 5.0 ng/kg, platelets lost approximately 50% of their responsiveness to PGI2. ADP-induced aggregation was not significantly inhibited ex vivo by the infusion of 2.5 ng/kg/min PGI2. During the infusion of 5.0 ng/kg/min PGI2, ADP-induced aggregation was inhibited at 24 and 48 hrs, but by 72 hrs, the platelets began to respond to ADP more like control cells even though the PGI2 X Na infusion was continuing. When the infusion was abruptly terminated a hyperaggregable response (rebound) to exogenous ADP was observed. In subjects where the 5.0 ng/kg/min infusion was gradually "tapered off" over a 12 hr period, there was no evidence of platelet hyperaggregability at the time points studied.

Adenosine Diphosphate↗
PubMed1989

Reduction in platelet-binding immunoglobulins and improvement in platelet counts in patients with HIV-associated idiopathic thrombocytopenia purpura (ITP) following extracorporeal immunoadsorption of plasma over staphylococcal protein A-silica.

Platelet-directed antibodies and circulating immune complexes (CIC) were removed from plasma of patients with human immunodeficiency virus (HIV) infection and idiopathic thrombocytopenic purpura (ITP) by extracorporeal immunoadsorption using columns of Staphylococcal protein A-silica (Prosorba columns). In addition, stimulation of a broadly cross-reactive anti-F(ab')2 antibody response was observed. These antibodies also appeared to play a role in the additional removal of platelet-directed immunoglobulins (Igs) and CIC from plasma. Removal of these components from plasma was associated with diminishing levels of antibodies and CIC on patient platelets and significant increases in platelet counts. Extracorporeal immunoadsorption of IgG and CIC from plasma is a beneficial new treatment modality for HIV-associated ITP.

Acquired Immunodeficiency Syndrome↗
PubMed2003

Low platelet counts alone do not cause bleeding in an experimental immune thrombocytopenic purpura in mice.

BACKGROUND AND OBJECTIVES: The physiopathogenesis of hemorrhagic phenomena in patients with autoimmune thrombocytopenic purpura is associated with low platelet levels. In the present work the relation between thrombocytopenia and bleeding was examined. The possible participation of endothelial cells in bleeding was also investigated. DESIGN AND METHODS: Immune thrombocytopenia and bleeding were studied in mice injected with anti-mouse and anti-human platelet polyclonal rabbit IgG. Platelet levels were measured at different times and bleeding signs were systematically recorded. ANOVA tests were used to compare platelet levels. Binding of anti-platelet antibodies to vascular endothelial cells was analyzed by immunohistochemistry. RESULTS: Three different doses of anti-platelet IgG caused the same low platelet levels, but bleeding occurred only with high doses of anti-platelet IgG irrespective of the platelet levels. No inflammation around blood vessels was observed in paraffin-embedded tissue sections of organs. Immunohistochemistry demonstrated anti-platelet antibodies bound to vascular endothelium. INTERPRETATION AND CONCLUSIONS: We showed lack of correlation between platelet counts and bleeding in a murine model. The binding of anti-platelet IgG to endothelial cells of small vessels is an indication that antibody-mediated endothelial activation, in addition to thrombocytopenia, could be participating in bleeding.

Animals↗
PubMed2006

Factors that influence morbidity and mortality in severe preeclampsia, eclampsia and hemolysis, elevated liver enzymes, and low platelet count syndrome.

OBJECTIVE: To evaluate the prognostic factors affecting morbidity and mortality in severe preeclampsia, eclampsia and hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome cases. METHODS: We retrospectively evaluated, 2245 cases who delivered in the Department of Obstetrics and Gynecology, Faculty of Medicine, Cukurova University, Turkey between January and December 2002. Ninety-three cases had severe preeclampsia, 26 cases eclampsia, 19 cases HELLP syndrome, and 6 cases with eclampsia and HELLP syndrome were included in this study. The pregnancy induced hypertension cases were evaluated retrospectively for socioeconomic status, obstetrical history, biochemical parameters, and maternal complications. RESULTS: The incidence of preeclampsia was 20.1% (453/2245), the incidence of severe preeclampsia, eclampsia, and HELLP syndrome was 6.4% (144/2245). These ratios are higher than that reported in the English literature. The complication rate was 38% in severe preeclampsia cases. Among the severe preeclampsia cases, 32 had eclampsia (22.1%), and 25 had HELLP syndrome (17.3%). CONCLUSION: The most important biochemical marker for maternal mortality is bilirubin levels. Maternal mortality was statistically higher in cases with jaundice. Also, there was a statistically significant relation between maternal complications and liver function tests, lactate dehydrogenase levels, and low platelet levels.

Adolescent↗
PubMedDate not supplied

Effects of cephalothin, cefazolin, and cefmetazole on the hemostatic mechanism in normal dogs: implications for the surgical patient.

Twenty-six female beagles were used to evaluate the effects of intravenous and long-term subcutaneous administration of cephalothin, cefazolin, and cefmetazole on platelet function and the coagulation cascade. Platelet aggregation in response to an adenosine diphosphate (ADP) agonist, bleeding time, platelet count, platelet size, prothrombin time (PT), and activated partial thromboplastin times (aPTT) were evaluated before and 90 minutes after two intravenous doses (22 mg/kg) of cephalothin, cefazolin, and cefmetazole given at 90-minute intervals. Dogs given saline injections were used as controls. Platelet count, platelet size, PT, and aPTT were evaluated after 7 days of subcutaneous administration of saline, cefazolin, and cefmetazole (22 mg/kg every 8 hours). A significant decrease in platelet aggregation in response to ADP was detected 90 minutes after intravenous administration of cephalothin. Bleeding time was increased significantly 90 minutes after intravenous administration of cefmetazole. Platelet size was decreased significantly 24 hours after onset of the study in all animals, including controls. No significant changes in platelet count, platelet size, PT, or aPTT were detected after 7 days of subcutaneous administration. Cefazolin had no adverse effects on platelet aggregation in response to ADP, bleeding time, platelet count, platelet size, PT, or aPTT. Therefore, cefazolin should be considered as a perioperative antibiotic in dogs with conditions predisposing to hemostatic complications.

Animals↗
PubMed1998

Platelet count and survival in patients with colorectal cancer--a preliminary study.

In a previous report we found an inverse correlation between pre-operative platelet count (PlC) levels and the risk of post-operative pulmonary embolism in patients undergoing hip surgery. In the present study, we prospectively evaluated the prognostic significance of pre-operative PlC levels on survival in 180 consecutive patients undergoing surgery for colorectal cancer. Other major clinicopathological parameters studied were age, gender, Dukes' stage, duration of surgery, pre-operative haemoglobin levels and transfusion requirements. There were no significant differences in mean pre-operative PlC levels according to tumor stage. Thirty-three patients (18%) died during follow-up (3-23 months, median: 13 months). Univariate analysis (Kaplan-Meier estimates) showed that advanced tumor stage (p < 0.001), duration of surgery (p < 0.05) and a high pre-operative PlC level (p < 0.001) were significantly associated to a poor survival. The multivariate Cox analysis revealed that tumor stage (RR:5.734; 95%C.I.: 2.644-12.44), a high pre-operative PlC level (RR: 2.467; 95%C.I.: 1.117-5.452), and to a lesser extent the patients' age remained independent prognostic variables for mortality. The findings of this preliminary study may be of interest from the point of view of pathogenesis, but also clinically, since they might be used in the decision as to which patients or groups of patients should receive more aggressive therapeutic intervention.

Aged↗