The effects of platelet apheresis in total hip replacement surgery on platelet activation

BACKGROUND: Autologous platelet rich plasma (PRP) harvest with autotransfusion devices has been used for 10 years in cardiac surgery and recently in orthopedics as a blood saving method. The quality of the harvested platelets has not been adequately examined, in part because of methodological difficulties in studying platelet function during surgery. METHODS: Twenty patients undergoing primary total hip replacement (THR) were studied. Ten patients underwent an immediate preoperative platelet apheresis to obtain concentrated platelet rich plasma (c-PRP). The other 10 patients not undergoing apheresis were allocated to a control group. Platelet activation was evaluated as the population expressing P-selectin on the surface of platelets in the c-PRP and in blood samples collected pre-, per- and postoperatively. The method used was flow cytometry. RESULTS AND CONCLUSIONS: A minor population of activated platelets was found to be circulating in the patients' blood, with a highly significant difference between patients (P = 0.005), and with a range of 1-23% in peroperative activation. PRP harvest did not significantly alter platelet activity. The platelet apheresis procedure did not inhibit platelet function in the c-PRP, as judged by a high proportion of platelets that could be activated in ADP stimulation experiments (mean value +/- SD 86% +/- 7.5%).     

Technical difficulties and perioperative complications of retrogasserian glycerol rhizotomy for trigeminal neuralgia

In 139 patients, 260 consecutive retrogasserian glycerol rhizotomies for trigeminal neuralgia were retrospectively analyzed regarding technical surgical difficulties and immediate and early complications. Technical obstacles occurred in 47.3%. In 21 cases (8.1%), the surgical procedure had to be interrupted due to circumstances such as vasovagal reactions, cardiac arrest, or difficulties to find the trigeminal cistern. Complications or side effects, being either transient or persistent, occurred in 67.3%. In the vast majority, those unwanted effects were related to mild sensory deficits. However, in 28.1% the complications were other than mild affection of facial sensibility. These slightly graver complications included labial herpes (3.8%), anesthesia dolorosa (0.8%), moderate or severe affection of sensibility (18.8%), dysesthesia (22.7%), chemical meningitis (1.5%) and infectious meningitis (1.5%). In 5 patients (1.9%) hearing was affected. In one of them, this condition was also brought about by tinnitus, and in another patient a preexisting tinnitus deteriorated. Although the frequency of surgical difficulties was high, the success of the glycerol injection was hampered only in a minor number of procedures. The frequency of complications and side effects was high, but they were mostly mild due to their nature and non-disabling for the patient. However, long-lasting disabling side effects occurred, and this should not be neglected when informing patients preoperatively. The surgical training needed to perform the procedure is stressed, and the use of prophylactic antibiotics when accidentally penetrating the oral bucca is recommended. We consider retrogasserian glycerol rhizotomy to be a good surgical option for patients with trigeminal neuralgia not suitable for microvascular decompression and when pharmacological therapy is not sufficient or is not tolerated.     

The apparent plasticizing effect of polyethylene glycol (PEG) on the crystallinity of spray dried lactose/PEG composites.

Aqueous solutions of lactose and polyethylene glycol (PEG) were spray dried in a Büchi Model 191 spray dryer with the aim to investigate the effect of PEG on the crystallinity of the composite. A PEG concentration of 10.7% by weight of solids was studied for PEG 200, 600, 1500, 4000 and 8000. For PEG 200 and 4000 additional concentrations from 1.5-19.3% to 1.5-32.4%, respectively, were investigated. The spray dried composites were analysed with X-ray powder diffraction and modulating differential scanning calorimetry. The crystallinity of lactose in the composites varied from 0% to 60%, dependent on the molecular weight and concentration of PEG. Apparently, lactose crystallinity is promoted by low molecular weight and high concentration of the PEG. PEG did not affect the lactose glass transition temperature. It is suggested that lactose and PEG are solidified separately during spray drying and that partial crystallization of lactose is associated with effects of PEG on the rate of drying.     

Fatty acid content of plasma lipid fractions, blood lipids, and apolipoproteins in children fed milk products containing different quantity and quality of fat

BACKGROUND: Differences in fatty acid content of plasma lipid fractions and serum lipid concentrations were investigated among young children fed different milk diets composed to achieve a recommended saturated fat intake. METHODS: Thirty-eight healthy children were randomly assigned to one of four feeding groups at 12 months: 1) low-fat milk (1.0 g/dL cow's milk fat); 2) standard-fat milk (3.5 g/dL cow's milk fat); 3) partially vegetable fat milk (3.5 gtat/dL fat; 50% vegetable fat: rapeseed oil); and 4) full vegetable-fat milk (3.5 gtat/dL fat; 100% vegetable fat: palm, coconut, and soy oil). Plasma fatty acids, blood lipids, and apolipoproteins were analyzed at 15 months, and dietary intakes at 12, 15, and 18 months. RESULTS: There were significantly lower percentage contributions of saturated fatty acids in plasma triglycerides in children fed low-fat milk or milk with 50% or 100% vegetable fat than in children fed standard-fat milk. Plasma polyunsaturated fatty acid levels were significantly higher in children fed milks with vegetable fat than in children fed standard-fat milk. Plasma saturated and polyunsaturated fatty acids in triglycerides most closely reflected dietary intake. Blood lipid concentrations were lower in children fed milk with 50% vegetable fat. CONCLUSIONS: Children fed milk with 50% or 100% vegetable fat, together with high vegetable-fat and low milk-fat dairy products have lower percentages of plasma saturated fatty acids and higher percentages of polyunsaturated fatty acids than children fed standard- or low-fat milk and dairy products.     

Fat intake and metabolism in Swedish and Italian infants

The purpose of the study was to compare fat intake and metabolism between two infant populations from Sweden and Italy given breast milk or similar infant formulas, but different weaning foods. Nutrient intake and fat metabolism were studied prospectively from 3-12 mo in 68 Swedish and 46 Italian healthy infants, breastfed or given similar infant formulas in combination with Swedish or Mediterranean weaning foods. Although nutrient intake and fat metabolism were similar at 6 mo, fat intake was lower at 12 mo in the Italian than in the Swedish formula group (p < 0.001). At 6 and 12 mo, higher dietary ratios of monounsaturated to saturated fatty acids (p < 0.01 and p < 0.001, respectively), and monounsaturated to polyunsaturated fatty acids (p < 0.05, p < 0.001) were found in the Italian than in the Swedish formula group. Total cholesterol and apolipoprotein B were lower at 6 mo (p < 0.01) in Italian breastfed infants than in Swedish ones. Lower concentrations at 6 and 12 mo of total cholesterol (p < 0.05, p < 0.05, respectively), apolipoprotein B (p < 0.05, p < 0.01) and triglycerides (p < 0.001, p < 0.01), and of apolipoprotein A1 (p < 0.01) at 12 mo, were found in the Italian formula group than in the Swedish one. In conclusion, plasma total cholesterol, apolipoprotein B and triglycerides were found to be lower in Italian infants than in Swedish infants during the second half of infancy. These findings may partly result from differences in fat compositions between Swedish and Mediterranean weaning diets and in total fat intake in late infancy. Differences in duration of breastfeeding and possibly in breast milk composition may also have influenced our results.     

Sentinel node localization in breast cancer patients using intradermal dye injection

In a series of 161 consecutive breast cancer operations, intradermal injection of Patent Blue was used to localize the sentinel node (SN). The surgical localization rate was 60%. Including the blue lymph nodes found by the pathologist, localization rate was 70%. After the first 103 operations, the surgical procedure was changed, resulting in a localization rate of 83%. Ten surgeons participated, but only one had previous experience with SN dissection. The others experienced a steep learning curve. Metastasis was found in 42 of 97 SNs (43%). In 15 cases (36%) metastasis was recognized only after step-sectioning and immunohistochemical staining for cytokeratin. In one case a benign epithelial inclusion was found. The sentinel node was false negative in 9.1% of cases. The consensus from the literature is that the best results are achieved using a combination of dye and isotopic techniques.     

Serological studies in acute maxillary sinusitis.

A comparison was performed between bacteriological and serological findings in 97 patients suffering from acute maxillary sinusitis. A significant titre change (larger than or equal to 2 titre steps) of complement-fixing antibodies to H. influenzae was demonstrated in 15 patients. H. influenzae was demonstrated in aspirated sinus secretions from 7 of these 15 patients. Further, titre changes to Neisseria catarrhalis were demonstrated in 25 patients. No significant titre changes in anti-streptolysin and anti-staphylolysin titres were demonstrated. The results are discussed briefly.     

Cancer vaccine potency: is there a dose/response relationship for patient-specific vaccines and clinical outcomes?

PURPOSE: Determination of potency is a challenging problem for patient-specific products derived from autologous cells. For several years, we have been investigating the safety and therapeutic potential of patient- specific vaccines derived from short-term autologous cell lines. We investigated whether clinical potency of these vaccines could be determined by retrospective correlation between the numbers of cells injected (quantity of tumor antigens) and clinical outcome. METHODS: The averages and standard deviations of irradiated tumor cells were determined for those patients who received the first 3 weekly injections, and for the subset that had a recording of results from tumor delayed-type hypersensitivity testing (DTH). Correlations were made between the numbers of cells injected and DTH conversion and survival. RESULTS: One hundred fifty-six patients received the vaccine product, 136 of whom received the first 3 weekly vaccinations. The most common reason for not receiving 3 injections or having a repeat tumor DTH test was rapidly progressive disease. Ninety-nine patients had cell count data for all 3 injections; 73 had a tumor DTH test at baseline and at week 4. The average number of cells injected over 3 weeks, in millions per patient, by quartile were: 6.0 +/- 1.8, 10.2 +/- 1.4, 15.1 +/- 1.4, and 31.2 +/- 9.8, with respective median survivals of 24.7, 25.5, 24.0, and 21.0 months, with the respective number of DTH conversions being 4, 8, 4, and 6. There were no statistical differences in survival or in the number of patients who had a positive tumor DTH test at week 4. CONCLUSIONS: We were unable to define potency--based on a relationship between the number of tumor cells injected as part of vaccination and survival or the reactivity to pure autologous tumor--in a tumor DTH test, over the range of 2-30 million injected cells over 3 weeks.