Mean platelet volumes: facts or artifacts?

Blood samples collected after venipuncture and skin-puncture from a series of ten healthy volunteers were used to determine platelet counts, mean platelet volumes (MPVs), and platelet distribution width (PDW). Measurements were performed on untreated venous whole blood and on whole or diluted samples, with or without anticoagulants. In this study, platelet indices were significantly different in untreated venous whole blood in comparison with blood from skin puncture and whole blood with anticoagulant.

Unpredictable effects of K3 EDTA on mean platelet volume.

The changes of mean platelet volumes (MPVs) begin immediately upon exposure of the blood to K3EDTA, and differences from sample to sample are unpredictable, predominantly in the first two hours from the venipuncture. MPVs variations can range from -25 to 23.1% in respect to MPVs in untreated whole blood immediately processed. These results were obtained by a new electrooptical device (Technicon H X 1) that provides complete blood cell counting and sizing. If whole blood is collected and diluted with a reagent used by the instrument to sphere and fix red blood cells and platelets, MPVs values do not change significantly within 180 minutes from venipuncture. This approach allows one to study the true values of MPVs on Technicon H X 1.

Advantages of a new anticoagulant in routine hematology on the Coulter Counter S-Plus STKR analyzer.

The authors report the advantages of a new anticoagulant-antiaggregant mixture that avoids the deleterious effects of ethylenediaminotetraacetic acid (EDTA) on mean platelet volume and also prevents EDTA-induced platelet clumping. It is suitable for routine cell counting and sizing with the Coulter Counter S-Plus STKR. The values of the common hematologic parameters agree well with those from EDTA-treated samples and are stable for at least eight hours after sampling.

Procedure for effective separation of high-density lipoproteins in normal serum and hypertriglyceridemic samples.

A chemical procedure for high-density lipoprotein (HDL) separation in normo- and hyperlipidemic sera has been developed. The procedure is effective up to 25 mmol/L of serum triglycerides and the constituents of the precipitation mixture (dextran sulfate, PEG-6000 and MgCl2) do not interfere with enzymatic assay of the HDL cholesterol.

Clinical chemical indexes and severity of coronary atherosclerosis.

The present study measured triglycerides (TG), total cholesterol (TC), HDL-cholesterol (HDL-C), LDL and LDL/HDL-C, TC/HDL-C and HDL-C/TC. 100 ratios in 261 men and women undergoing coronary arteriography. The results show that TG, TC, HDL-C and LDL levels are not related to the severity of coronary artery disease (CAD). The LDL/HDL-C, TC/HDL-C and HDL/TC.100 ratios are statistically related to the severity of CAD. The LDL/HDL-C ratio appeared to be the most sensitive index for reflecting CAD of mild severity with a predictive value of 83.3% at 76.6% specificity and at 77.7% sensitivity (cut-off: 3.20). Average values of LDL and HDL-C alone are not reliable indices of mild severity CAD.

Origin of glycosylated hemoglobin A1 in chronic renal failure.

In chronic renal failure both HbA1 and HbA1c levels have been reported to be elevated. In order to investigate the causes of such increase we measured HbA1 (cation-exchange chromatography), blood urea nitrogen, arterial blood pH, plasma bicarbonate, phosphatemia, serum iron and serum ferritin before dialysis in 60 uremic patients receiving long term hemodialysis. The increased levels of HbA1 do not correlate with glucose intolerance, phosphatemia, blood urea nitrogen, time averaged concentration of urea, serum iron and serum ferritin. On the contrary the presence of a highly significant correlation between HbA1 and arterial blood pH (p less than 0.001) and between HbA1 and plasma bicarbonate (p less than 0.001) seems to emphasize a major role for acidosis in increasing the HbA1 levels in uremic patients on long term hemodialysis.

Identification of the sentinel lymph node stained with blue dye in breast cancer patients.

PURPOSE: This study aimed to evaluate the reproducibility of sentinel lymphadenectomy in breast cancer patients (T1N0M0 and T2N0M0) and its possibility of predicting the total axillary behavior. METHODS: A total of 25 patients were evaluated, all presenting palpable mammary nodes between 1.5 and 5 cm (T1 and T2), with clinically negative axillary lymph nodes (N0). After an incisional biopsy of the tumor and histopathological confirmation of invasive breast carcinoma, a study of the sentinel lymph node took place with a peritumoral injection of 4 ml of blue dye at 2.5%. After waiting for 15 to 20 minutes, a search for the blue stained lymphatic vase in the axillary fat was carried out, which would lead to the sentinel lymph node, stained or not. At that point, a mastectomy (20 patients) or a quadrantectomy (5 patients) was performed, both with axillary lymphadenectomy at grades 1, 2 and 3. The sentinel lymph nodes and the material from the axillary dissection were sent separately for an anatomicopathological test in paraffin. RESULTS: The lymph nodes were identified in 19 patients, which represented a 76% detection rate. There was a concordance between the sentinel lymphadenectomy and the standard axillary dissection in 68.4% of the patients. The false-positive and the false-negative rates observed were 10% and 55.5%, respectively. A higher detection rate was found in tumors larger than 2 cm and situated in external quadrants. CONCLUSIONS: Sentinel lymphadenectomy identified the sentinel lymph node in the majority of the patients in this study, although the high rate of false-negatives observed prevented an accurate staging.

[Obstetric factors associated with low birth weight]. / Fatores obstétricos associados ao baixo peso ao nascer.

An analysis was made of 18,804 of 19,446 consecutive births of the number analysed 15.93% presented low birth-rate. Significant statistical association was found in relation to maternal age, pre-natal care, previous pregnancies, smoking and gestational age at birth. Measures with a view to the attenuation of the problem are proposed, among them being: educational programs for teenagers on human reproduction, programs designed to create awareness of the harm done by smoking, amplification of antenatal assistance, medical programs for the limitation of premature labor, all of these and others, in association with programs of socio-economic support.

Sentinel lymph node in endometrial cancer.

The aim of this study was to evaluate the possibility of identifying the sentinel lymph node and involvement of neoplastic cells in patients with endometrial carcinoma limited to the uterus, and also its correlation with the conditions of other pelvic and para-aortic lymph nodes. Forty patients with endometrial carcinoma, clinical staging I and II, were submitted to complete surgical staging through laparotomy, as recommended by FIGO in 1988. The sentinel node was investigated using patent blue dye in the myometrial subserosa. The sentinel node was excised and submitted to frozen section examination of specimen, stained with hematoxylin and eosin (H&E). Afterward, selective bilateral para-aortic and pelvic lymphadenectomy, total hysterectomy with bilateral salpingo-oophorectomy were performed. The lymph nodes excised were examined by means of paraffin-embedded slices stained with H&E and of imunohistochemistry with antikeratin antibody AE1/AE3. The sentinel lymph node was identified in 77.5% of patients (31/40), and 16.1% (5/31) presented neoplastic involvement in the node. In 25 cases of negative sentinel node, 96% (24/25) had no neoplastic involvement, and 4% (1/25) had other lymph node affected (false negative). In nine cases with no sentinel node identified, 55.5% (5/9) had lymph node involvement. The results of this study allow us to conclude that it is possible to identify the sentinel node using the methods described, and the pathologic examination significantly represents the same conditions of other pelvic and para-aortic lymph nodes.