Reducing transfusion requirements following total knee arthroplasty: effectiveness of a double infusion of tranexamic acid

OBJECTIVE

Blood loss following joint replacement surgery represents a relevant issue for orthopedic surgeons. The use of tranexamic acid (TXA) to reduce transfusion requirements has become mainstream. However, consensus about the starting time, methods, or volume of usage of TXA in joint replacement surgery has yet to be found. A retrospective study was conducted comparing pre- and post-operative infusion of TXA 15 mg/kg to a single pre-operative infusion.

PATIENTS AND METHODS

291 patients undergoing TKA were retrospectively reviewed. 109 received a single pre-operative dose of 15 mg/ kg TXA (single dose, SD group), 182 received a single pre- operative dose of 15 mg/ kg TXA followed by a second post-operative dose of 15 mg/kg TXA (double dose, DD group). The primary outcome was blood loss calculated from haematological values and perioperative transfusions. Secondary outcomes included the occurrence of major complications within the first postoperative year.

RESULTS

None of the patients reported adverse events. Blood transfusions were administered to 63 patients (13.5%) in the SD and 36 in the DD group (5.7%). Significant difference between the groups was observed (p < 0.005). No significant difference between the two groups was found concerning mean blood loss in drainage after the 24th hour and postoperative hemoglobin values (p = n.s.).

CONCLUSIONS

The study demonstrated that TXA possesses a good safety profile. In addition, pre- and post-operative infusion of TXA 15 mg/kg is more effective compared to single pre-operative infusion in reducing need for transfusion requirements.

From Low Hematocrit Physiology to Isovolemic Hemodilution

The aim of this study, starting from some concepts of physiology, was to deal with the ever growing question of intentional anemia. Physiology suitably expresses the linear relationship between hematocrit and blood fluidity, and at the same time explains how viscosity and aggregability are important co-factors in the circulation, in disease and in thromboembolic complications. The need to understand how a low hematocrit level, compared to the volemia, is a fundamental requirement in surgery, and even more so in surgery with a high risk of embolism, like orthopedic traumatology surgery. Normovolemic hemodilution was analyzed both for the risks it involves and for how much it sticks to the changes induced by a similar situation on the various organs and apparatus. The authors, based on their experience in the field of anesthesiology, propose an operating schedule to safely perform intentional normovolemic hemodilution, describing the preoperative, intraoperative and finally the postoperative period. In conclusion, the authors advocate a wider use of this technique, confirming its safety in relation to volemia.

Blood Saving Program: A Multicenter Italian Experience

To assess the causes of failure in a blood saving program and the consequent need for homologous transfusions during major orthopedic surgery, data were collected from six orthopedic centers where an autotransfusion program was carried out from 1992–1994. The 1,576 (1,016 female and 560 male) patients studied (average age 63.6 ± 10 years) were treated either for total hip prosthesis (1,144 pts) total knee prosthesis (212 pts), plate and screw removal plus hip prosthesis (8 pts), hip revision (cup 48 pts, stem 10 pts, cup plus stem 146 pts) and total knee revision (8 pts). Ninety percent of patients did not undergo homologous transfusions, which was significantly connected to: male sex (8% versus 11.7% p=0.02), younger age (63.2 vs 66.9 years, p=0.0001), higher weight (male 76 vs 70.7 Kg. p = 0.003, female 65.6 vs 61.9 Kg. p = 0.0003); higher baseline Hb (13.9 vs 12.8 gl dl, p = 0.0041), shorter operation time (110 vs 128 minutes, p = 0.0001); use of indobufen for antithromboembolic prophylaxis (indobufen 4.6% vs heparin calcium 15.2% vs low molecular weight heparin 9% p = 0.0001). On the contrary, the factors favoring homologous transfusions were: peripheral anesthesia (spinal and epidural 15.3% vs general 9.3% vs integrated 9.8% p = 0.016), total hip or knee revision, fixation device removal before hip prosthesis, systemic hypertension and coronary heart disease.

Tissue-specific downregulation of the adiponectin "system": possible implications for fat accumulation tendency in the pig

Adiponectin's beneficial effects are mediated by the AdipoR1 and AdipoR2 receptors (AdipoRs). The pig is a good model to study complex disorders such as obesity. We analyzed the expression of adiponectin, AdipoRs and some key molecules of energy metabolism (AMP-activated protein kinase α [AMPKα], p38 mitogen-activated protein kinase [p38 MAPK], and PPARα) in 2 pig breeds that displayed an opposite genetic behavior for energy metabolism: Casertana (CE), a fat-type animal, and Large White (LW), a lean-type animal. Muscle, liver, visceral and subcutaneous adipose tissues, and brain tissues were examined. The AdipoRs cDNA sequences were identical in the 2 breeds. AdipoRs mRNA expression, measured in all tissues, was significantly lower only in the 2 adipose tissues of CE pigs (P < 0.05). The muscle expression of AdipoRs, AMPKα, p38 MAPK, and PPARα was lower in CE than in LW animals (P < 0.01, P < 0.05, P < 0.01, P < 0.01, respectively). In liver, no molecule differed between breeds. The expression of both AdipoRs in visceral and subcutaneous adipose tissues was lower in CE pigs (P < 0.01). In brain, AdipoR1 and AMPKα expression was lower in CE pigs (P < 0.01), whereas AdipoR2 tended to be lower in CE than LW pigs (P = 0.05). In conclusion, our results suggest that tissue-specific downregulation of Adiponectin, AdipoRs, and of the key molecules of energy metabolism may be associated with the tendency of CE pigs to accumulate fat.

The absence of polymorphisms in ADRB3, UCP1, PPARγ, and ADIPOQ genes protects morbid obese patients toward insulin resistance

BACKGROUND AND AIMS

The insulin resistance (IR) is a major metabolic impairment in severe obesity, a multifactorial disease in which the importance of the effect of single nucleotide polymorphisms (SNP) associations in different rather than individual genes was established. The aim of this study was to test the predictive value of presence/absence of polymorphisms/ variants in β3-adrenergic receptor (ADRB3), uncoupling protein 1 (UCP1), peroxisome proliferator-activated receptor γ (PPARγ), and adiponectin (ADIPOQ) genes in diagnosing the IR in obesity.

SUBJECTS AND METHODS

We studied 112 (40 males, 72 females) severely obese (body mass index: 48.5±7.5 kg/m2) subjects recruited from the outpatient obesity clinic of Federico II University Hospital in Naples. Genomic DNA was extracted from peripheral leukocytes with a commercial kit. The gene polymorphisms Trp64Arg in ADRB3, -3826 A>G in UCP1, Pro12Ala in PPARγ, and c.268G>A, c.331T>C, and c.334C>T in ADIPOQ were characterized by TaqMan assay or by direct sequencing (ADIPOQ).

RESULTS AND CONCLUSION

Our results demonstrate that -3826A>G UCP1 polymorphism is associated with IR in morbid obesity. Further, the lack of any polymorphisms, Trp64Arg in ADRB3 and/or -3826 A>G in UCP1 and/or Pro12Ala in PPARγ and/or c.268G>A, c.331T>C and c.334C>T in ADIPOQ, appears a useful prognostic factor (NPV=100%) toward the IR onset in these obese patients representing a further parameter for an earlier and appropriate therapy.

Molecular analysis of the adiponectin gene in severely obese patients from southern Italy

BACKGROUND

Severe obesity is a major worldwide public health concern affecting 0.5-5% of the adult population. Adiponectin (Acpr30), an adipokine secreted from adipocytes, shows pleiotropic beneficial effects on obesity and related disorders. In this study, sequence analysis of Acpr30 gene (ACDC) was performed in a highly selected population of severely obese young adult patients from Southern Italy to investigate the associations between polymorphisms in the ACDC gene and the development of severe obesity concomitantly with other features of the metabolic syndrome.

METHODS

The ACDC gene was analyzed by direct sequencing in the severely obese patients (n=220) and compared to healthy controls (n=116). The associations between the ACDC gene single-nucleotide polymorphisms (SNPs) and the levels of serum Acpr30 as well as the correlation with the presence of severe obesity jointly associated with other features of the metabolic syndrome were also investigated. Total serum Acpr30 concentrations were measured by the ELISA method.

RESULTS

ACDC gene molecular screening revealed the presence of previously described SNPs and a new nucleotide alteration, c.355T>G, leading to a protein variant, p.L119V. Measurement of serum concentration of Acpr30 demonstrated lower levels of Acpr30 in the obese population compared to controls (30.5+/-28.3 vs. 43.9+/-35.7 microg/ml, p<0.01); in particular, significantly lower Acpr30 concentrations were observed in obese patients bearing c.-11377C>G SNP CG+GG genotypes than in those with CC genotype (22.9+/-20.5 vs. 33.1+/-29.4 microg/ml, p<0.05).

CONCLUSIONS

Our results confirmed that low serum levels of Acpr30 are related to severe obesity and a difference in protein expression is associated with variants in ACDC gene promoter region.

Metabolic syndrome and ADRB3 gene polymorphism in severely obese patients from South Italy

OBJECTIVE

To evaluate the prevalence of beta(3)-adrenergic receptor (ADRB3) Trp64Arg polymorphism and its relationship with the metabolic syndrome in severe obesity.

DESIGN

Cross-sectional outpatients study.

PATIENTS AND METHODS

In 265 (100 men) severely obese non-diabetic subjects and 78 (25 men) healthy volunteers, genomic DNA was isolated from peripheral leukocytes. In obese patients, plasma concentrations of leptin, lipids, glucose and insulin, the homeostasis model assessment index and blood pressure have been measured. The Trp64Arg mutation was identified with the real-time TaqMan method.

RESULTS

Neither genotype distribution nor allele frequency differed between the two groups. The metabolic syndrome prevalence was 59% in obese subjects, and was higher in men than in women (65 vs 55%: P=0.03). The body mass index (BMI) was related to age tertiles (beta=0.08; P<0.001; multiple linear regression) in Trp64Arg-positive obese subjects.

CONCLUSION

We confirm the high prevalence of the metabolic syndrome among severely obese subjects. ADRB3 polymorphism was significantly related to insulin resistance only in obese male subjects. Moreover, increased BMI was related to age in obese subjects with the ADRB3 polymorphism.

Contribution of weight cycling to serum leptin in human obesity

OBJECTIVE

To investigate to what extent serum leptin concentrations in obese humans are influenced by a history of weight cycling.

DESIGN

Cross-sectional study on serum leptin concentrations and body composition in a cohort of obese subjects in whom a retrospective recall of weight and diet history was made.

SUBJECTS

One hundred and twenty-eight obese patients (89 females and 39 males), aged 18-61 y, body mass index (BMI) 31.2-63.4 kg/m(2).

MEASUREMENTS

Serum leptin; various fatness and fat distribution parameters (by anthropometry and bioelectrical impedance analysis); history of overweight at puberty; number, magnitude and timing of previous diet episodes and of consequent weight regain by interview.

RESULTS

By univariate analysis, serum leptin concentrations were significantly correlated with weight, waist-hip ratio, percentage body fat, maximal percentage weight loss in a single diet episode, cumulative percentage weight loss in all diet episodes, cumulative weight regained in all diet episodes, but not with the number of diet episodes. All correlations related to anthropometric and body composition parameters were stronger for men, compared to women, although the male subgroup was smaller. On the contrary, there was a strong positive correlation between weight cycling parameters and serum leptin in women but not in men. Leptin concentrations were significantly higher in patients who were overweight at puberty than in those who were not overweight at puberty. After correction for percentage body fat, presence of overweight at puberty did not correlate any longer with leptin concentrations in either gender. In women, cumulative percentage weight loss in all diet episodes contributed an additional 5% to the variance of serum leptin in the overall model.

CONCLUSION

The positive correlation between weight cycling and leptin concentration in obesity is mainly accounted for the higher percentage body fat in obese weight cyclers, although in women weight cycling per se independently contributes to the variance of serum leptin.

Multivariate discriminant function based on six biochemical markers in blood can predict the cirrhotic evolution of chronic hepatitis

BACKGROUND

Serologic markers have been proposed for monitoring hepatic fibrosis in chronic active liver disease. Because none of these markers, when used singly, is totally satisfactory, we developed and evaluated a multivariate approach.

METHODS

We studied two cohorts of chronic hepatitis (54 patients) and cirrhosis patients (49 patients) to identify a panel of biochemical markers that discriminates between the two diseases. Using multivariate discriminant analysis, we selected a function, based on the concentrations of six biochemical markers (fibronectin, prothrombin, pseudocholinesterase, alanine aminotransferase, manganese superoxide dismutase, and N-acetyl-beta-glucosaminidase). We then prospectively validated this function on a second temporal cohort of patients.

RESULTS

Multivariate discriminant analysis correctly classified 93.7% of patients (94.3% of chronic hepatitis and 92.9% of cirrhosis patients) in the first cohort and 85% of patients (89.5% of chronic hepatitis patients and 81% of cirrhosis patients) in the second cohort.

CONCLUSIONS

Discriminant analysis of results of six inexpensive biochemical markers provides a high predictive value for differentiation between liver cirrhosis and chronic hepatitis. Consequently, these biochemical markers condensed into a multivariate discriminant analysis value for each patient provide information that can be contributory for subsequent options during the evolution of the natural history of chronic hepatitis.

Interactions between metabolic disorders (diabetes, gallstones, and dyslipidaemia) and the progression of chronic hepatitis C virus infection to cirrhosis and hepatocellular carcinoma. A cross-sectional multicentre survey

BACKGROUND

Diabetes, gallstones and dyslipidaemia are widespread, metabolically related, disorders that can affect the liver, often in a clinically silent fashion.

AIM

To investigate whether the presence of these disorders may worsen chronic viral disease by inducing additional liver damage, revealed by variations in serum increases of aminotransferase, alkaline phosphatase and gamma-glutamyl-transpeptidase activities.

PATIENTS AND METHODS

This retrospective, cross-sectional study involved 1,195 patients with chronic hepatitis C virus infection: 47.2% chronic hepatitis, 45.2% cirrhosis, and 7.6% hepatocellular carcinoma. 14.9% of patients had enzymatic cholestasis, defined as combined increase of alkaline phosphatase and gamma-glutamyl-transpeptidase. A Log-linear statistical model was applied to the following variables: stages of liver disease, diabetes, cholelithiasis, hypertriglyceridaemia, hypercholesterolaemia, and enzymatic cholestasis.

RESULTS

Log-linear analysis, applied to categorical variables, revealed, for the first time, a three-way interaction between the stages of chronic liver disease, diabetes, and enzymatic cholestasis. Two-way interactions demonstrated that liver disease stages correlated directly to the prevalence of cholelithiasis and inversely to hypercholesterolaemia. Irrespective of the liver disease stage, hypertriglyceridaemia correlated to hypercholesterolaemia.

CONCLUSIONS

This study discloses a synergistic liver damaging effect of diabetes and hepatitis C virus. The three-way interaction obtained by our analysis suggests that diabetes is a risk factor for the progression of viral liver disease and that it contributes to disease evolution, at least in part, by induction of cholestasis.

Oxidative status of plasma and muscle in rabbits supplemented with dietary vitamin E

Thirty New Zealand white rabbits, mean weight 2 kg, were divided into three equal groups balanced for body weight and randomly assigned to a diet containing 60 (C), 150 (T1) or 375 (T2) mg/kg of all-rac-alpha-tocopheryl acetate. After 29 days, the animals were slaughtered. alpha-Tocopherol was assayed in muscle (longissimus dorsi) and plasma; triglycerides and cholesterol (total, high density lipoprotein, low density lipoprotein) were analysed in plasma; reactive oxygen metabolites (ROMs) were analysed in serum; and thiobarbituric acid-reactive substances (TBARS) were analysed in muscle. There were no body weight and food intake differences between the groups. The plasma vitamin E and vitamin E:lipid ratio were significantly higher in groups T1 and T2 than in C, but increases were not linearly related to dietary levels. Muscle alpha-tocopherol concentrations in the treated groups were significantly higher than in C, and linearly related (R =.67) to the vitamin E:lipid ratio. ROM and vitamin E levels in blood were inversely related (R =.74), with ROMs significantly lower in the treated groups than in C. The 60-mg/kg dose of C recommended by the National Research Council was unable to control ROM production. Lipid oxidation in muscle was significantly lower in T2 than in the other groups, and TBARS correlated significantly with muscle vitamin E (R =.61) and serum ROM (R =.73). These data suggest that vitamin E supplemented at 375 mg/kg diet can effectively control ROM production and improve muscle lipostability. ROM assay provides a useful indirect estimate of the oxidative status of muscle in vivo.

Growth, slaughter and intra-muscular collagen characteristics in Garganica kids

Growth performance, ossification of metacarpal growth plate, and intra-muscular collagen characteristics in three muscles of 10 intact male Garganica kids were studied. Each week, starting from the 47th day of age to slaughter (75th day of age), kids were weighed and blood samples taken for plasma non-protein hydroxyproline analysis. At slaughter, metacarpal, metatarsal bones and metacarpal growth plate thickness were measured. The semitendinosus (ST), semimembranosus (SM), and rectus medialis (RM) muscle samples were analysed for collagen concentration and hydroxylysyl pyridinoline (HP) cross-links. ST muscle had a collagen amount higher than SM and RM (P<0.01), and RM muscle had the highest (P<0.01) HP concentration. Tenderness index was the highest (P<0.01) in RM muscle. Animal growth rates slowed, starting from 61st day of age (P<0.01); this trend coincided with a marked reduction in concentration of plasma non-protein hydroxyproline (P<0.01). In addition, plasma non-protein hydroxyproline concentration was positively correlated (r=0.61, P=0.001) with growth rate of animals, suggesting that collagen turnover decreases during a slow growth phase. Based on the metacarpal growth plate width, the rate of bone ossification appears to be slower in goats than sheep.

Prediction of lean body mass from multifrequency segmental impedance: influence of adiposity

The aim of the study was to determine the influence of adiposity on the relationship between bioelectrical impedance (BIA) measurements of body segments and estimation of body composition by dual-energy X-ray absorptiometry (DXA). Multiple frequencies of whole body and segmental impedances were measured in 68 normal-weight and obese subjects (46 women and 22 men), mean age 37.2+/-14.8 years (range, 18-69). Total and appendicular lean body mass (LBM) assessed by DXA correlated significantly with total and segmental impedance values adjusted for stature in both obese and normal-weight subjects. Best fitting equations for the prediction of appendicular LBM from segmental impedance measurements were derived for the arm and leg with and without the inclusion of adiposity (the percentage of body fat measured by DXA) in the regression models. Best prediction was obtained at low frequency for the arm and high frequency for the leg. Adiposity appears to significantly influence the prediction of leg LBM by BIA. These preliminary observations need further validation to provide an accurate assessment of appendicular LBM assessment by BIA.

Epoetin alfa in low hematocrit patients to facilitate autologous blood donation in total hip replacement: a randomized, double-blind, placebo-controlled, dose-ranging study

We investigated the safety and efficacy of preoperative epoetin alfa used in conjunction with preoperative autologous blood donation (PAD) in 40 anemic orthopedic surgical patients undergoing hip replacement surgery [hematocrit (Hct) </=39%]. Patients were randomized 25-35 days before surgery to twice weekly intravenous (i. v.) epoetin alfa (300, 150, or 75 IU/kg) or placebo treatments supplemented with 200 mg i.v. iron. Epoetin alfa facilitated dose-dependent increases in PAD (4.3 units, 300 IU/kg; 3.4 units, 150 IU/kg; 3.0 units, 75 IU/kg; 2.1 units, placebo), and minimized reductions in Hct associated with repeated phlebotomy. All epoetin alfa doses were well tolerated and safe. Our results indicate that preoperative epoetin alfa dose-dependently stimulates erythropoiesis and facilitates PAD in anemic orthopedic patients, which may benefit patients by reducing their exposure to the risks of allogeneic transfusion, hastening recovery and discharge from hospital.

Body composition in italian and Danish women

The objective of this cross-sectional study was to compare the body composition and fat distribution measured by dual energy X-ray absorptiometry (DPX, Lunar) in different age decades of age-matched Danish and Italian women. The subjects comprised 133 healthy Italian women (age 20-60 years) age-matched to a representative sub-sample of healthy Danish women (n=375). Total and abdominal body fat tissue mass were measured by dual-energy X-ray absorptiometry. Italian women were shorter and fatter compared with age-matched Danish women, but in middle-age, had a less abdominal fat distribution. There was no difference in total body bone mineral density.

Resting metabolic rate in Italians: relation with body composition and anthropometric parameters

The objectives of this study were to obtain values for resting metabolic rate in Italians in relation to parameters of body composition, and to compare them to predicted values using the FAO/WHO/UNU equation. We performed a cross-sectional observational study of 131 healthy subjects (46 males and 85 females) at the Human Nutrition Unit, University Tor Vergata, Rome. Body composition was determined by dual energy X-ray absorptiometry (DXA) and resting metabolic rate was calculated using the Weir formula. Resting metabolic rate was 1,865 +/- 234 kcal/day in males and 1,354 +/- 154 kcal/day in females. These values decreased slightly with age. The relationships with weight and age were stronger than that with lean mass from DXA as independent variables in multiple regression analysis. Mean resting metabolic rates predicted with FAO/WHO/UNU and Harris-Benedict formula were not significantly different from measured values except for the Harris-Benedict value for females (p < 0.01). Individual differences between measured and predicted values were notably high. The measured values were higher than those reported in the literature. The prediction of resting metabolic rate is more accurate with simple anthropometric parameters than with fat-free mass obtained by DXA. The individual error in the predicted values can be so high that for individual use a measured value is preferred over an estimated value.

Effects of intramuscular injection of alpha-tocopheryl acetate on fatty acid profile in lamb liver

The effects of intramuscularly administrated vitamin E on total lipids, fatty acid profile, and lipid stability to oxidation was investigated in lamb liver. Twenty-four 5-day-old lambs were allotted to 4 groups of 6 each and given respectively 0 (control), 125, 200, 300 mg dl-alpha-tocopheryl acetate weekly from day 5 to 33. alpha-Tocopherol stored in lamb liver at the end of experiment showed linear correlation with the level of injected vitamin E. No effect on total lipids was found. A decrease in the level of liver thiobarbituric-acid reactive substances (TBARS), significantly correlated with liver alpha-tocopherol content, was found in vitamin E groups. The amount of linoleic and linolenic acids significantly increased in the vitamin E groups as compared to control group, and were correlated with the liver alpha-tocopherol content. TBARS were negatively correlated with the concentration of unsaturated fatty acids. Finally, in the liver of the treated groups, vitamin E concentrations in the range 30-50 micrograms/g showed adequate for an efficient protection from peroxidation of membrane lipids, and determined an increase in the unsaturated to saturated fatty acid ratio.

Influence of multiple injections of vitamin E on intramuscular collagen and bone characteristics in suckling lambs

We studied the influence of vitamin E on intramuscular collagen characteristics and on metacarpal growth plate evolution in suckling lambs. Twenty-four 5-d-old Ile de France suckling male lambs were divided into four equal weight groups, and weekly i.m. injections of DL-alpha-tocopheryl acetate (Control group, 0 IU; Group 1, 625 IU; Group 2, 1,000 IU; and Group 3, 1,500 IU) were given until the lambs were 33 d old. Blood samples were withdrawn for plasma alpha-tocopherol, cholesterol, and triglyceride analyses when the lambs were slaughtered at 40 d of age. Hot carcass weight, metacarpal and metatarsal bone characteristics, and metacarpal growth plate width were measured. After 24 h at 2 to 4 degrees C, semitendinosus muscles were removed for intramuscular collagen analyses. Weight was not influenced by treatment, but lambs in Group 1 had a higher (P < .01) intramuscular collagen content than the other groups. A positive quadratic correlation was found between total collagen and vitamin E doses (r = .511; P < .05). Amount and percentage of soluble collagen increased in muscles of all three vitamin E-treated groups compared with the control group. However, hydroxylysyl pyridinoline concentration decreased with vitamin E injection, but the difference compared to control lambs was only significant for the group injected with 1,000 IU. Amount of soluble collagen was strongly correlated to total collagen concentration (r = .879; P < .0001). It was also related to the alpha-tocopherol/(cholesterol + triglycerides) ratio in plasma (r = .431; P < .04). However, the correlation between soluble collagen percentage and alpha-tocopherol concentration in plasma was not significant (r = .369; P < .08). Bone length, weight, and diameter did not change, but the thickness of metacarpal growth plate increased as the DL-alpha-tocopheryl acetate dose increased; in Groups 2 and 3, the growth plate was significantly wider than in Group 1 and the controls. Growth plate width correlated with alpha-tocopherol/(cholesterol + triglycerides) ratio in plasma (r = .481; P < .02).

Influence of dietary vitamin E supplementation on "heavy" pig carcass characteristics, meat quality, and vitamin E status

Crossbred "heavy" pigs (average weight 120 kg, slaughter weight above 160 kg) were supplemented with all-rac-alpha-tocopheryl acetate during the last 60 d of late finishing at doses of 25 (control), 50, 100, 200, or 300 mg/kg of diet. At the end of this period, the pigs were slaughtered. Carcass characteristics and the meat quality of pork chops from longissimus muscle (LM) at the last lumbar vertebra were evaluated on eight barrows from each dosage group. Alpha-tocopherol levels were determined in plasma during supplementation and in LM muscle after slaughter. Thiobarbituric acid reactive substances (TBARS) and drip loss were also evaluated in meat. Plasma alpha-tocopherol levels increased (P < .005) during supplementation in treated animals compared to controls, with a peak at 40 d. Alpha-tocopherol levels were higher (P < .05) in LM from pigs treated with 300 mg/kg than in controls (8.4 vs 5.6 microg/g). Dressing percentages correlated (P < .05) with the ratio of plasma alpha-tocopherol levels to the sum of cholesterol and triglycerides. Inhibition of TBARS during storage was related (P < .005) to vitamin E supplementation level, but drip losses in chops were not related to supplementation levels. We concluded that dietary vitamin E supplementation to heavy pigs during the last 60 d of finishing improves dressing percentage, reduces lipid oxidation, and increases the alpha-tocopherol concentration of tissues.

Hyperbaric oxygen increases plasma exudation in rat trachea: involvement of nitric oxide

This study investigates the microvascular permeability changes in tracheal tissue of rats exposed to hyperbaric oxygen (HBO). Rats, following exposure to HBO or ambient air (control animals) for 1.5, 3 and 6 h, were prepared for recording of nitric oxide exhaled (FENO) in air using a chemiluminescence analyser. The level of FENO was not statistically different in the two groups. Plasma exudation, evaluated by measuring the leakage of Evans blue (EB) dye into the tracheal tissue, was significantly elevated (48, 86 and 105% at 1.5, 3 and 6 h, respectively) in HBO-treated rats. Plasma exudation in the trachea of control rats was significantly increased (42%, P<0.05) by NG-nitro-L-arginine methyl ester (L-NAME), whereas it was significantly reduced (31%, P<0.05) in rats exposed to HBO for 3 h. N-acetylcysteine (NAC) and flunisolide significantly prevented the increase in plasma leakage in HBO-treated rats. In contrast, indomethacin was devoid of anti-exudative activity in these experiments. Western immunoblot showed a significant increase in the level of inducible nitric oxide synthase (iNOS) protein in the tracheal homogenates of HBO-treated rats, as compared to basal levels. These results indicate that nitric oxide (NO) is involved in the maintenance of microvascular permeability in tracheal tissue of rats. The protective effect observed with the steroid seems to support this hypothesis. Furthermore, the beneficial action of NAC underlines that reactive oxygen species participate in the microvascular permeability changes observed in tracheal tissue of rats exposed to HBO.

Change in major amputation rate in a center dedicated to diabetic foot care during the 1980s: prognostic determinants for major amputation

From 1990 to 1993, 115 diabetic patients were consecutively hospitalized in our diabetologic unit for foot ulcer and 27 (23.5%) major amputations were carried out. The major amputation rate of this series of cases was compared with that occurring in diabetic subjects taken into our hospital for foot ulcer in two previous periods: 1979-1981 (17 major amputations in 42 inpatients or 40.5%) and 1986-1989 (26 major amputations in 78 inpatients or 33.3%). The comparison shows a progressive reduction in major amputation rate [Odds ratio 0.66, 95% confidence interval (CI) 0.46-0.96]. Univariate and multivariate analysis, carried out in the population of the 1990-1993 period, in order to detect the independent factors associated with major amputation show the following prognostic determinants of major amputation: Wagner grade (odds ratio 7.69, CI 1.58-37.53), prior stroke (odds ratio 35.05, CI 3.14-390.53), prior major amputation (odds ratio 3.49, CI 1.26-9.38), transcutaneous oxygen level (odds ratio 1.06, CI 1.01-1.12), and ankle-brachial blood pressure index (odds ratio 4.35, CI 1.58-12.05), while an independent protective role was attributed to hyperbaric oxygen treatment (odds ratio 0.15, CI 0.03-0.64). In accordance with other studies, we, therefore, conclude that a comprehensive protocol as well as a multidisciplinary approach in a dedicated center can assure a decrease in major amputation rate. The parameters of limb perfusion were the modifiable prognostic determinants most strongly predictive for amputation.

Influence of acetylcysteine on aggravation of ischemic damage in ex vivo hearts of rats exposed to hyperbaric oxygen

Rats were exposed to hyperbaric oxygen (HBO = 100% oxygen; 2.5 atmospheres absolute pressure) for 6 h. Isovolumic left heart preparations from these animals were subjected to global low flow-ischemia (perfusion rate from 12 ml/min to 2 ml/min for 40 min) and reperfusion. Hearts from rats not exposed to HBO underwent the same ischemic-reperfusion procedure (controls). As compared to control, HBO treatment caused in ex vivo hearts a significant aggravation of cardiac ischemic picture as indicated by a marked increase in left ventricular end diastolic pressure (LVEDP) and reduced post ischemic left ventricular developed pressure (LVDP). At the end of the ischemic and reperfusion periods LVEDP values were 6.8 (p < 0.001) and 8 (p < 0.001) times higher than the corresponding control values. Moreover, LVDP and coronary perfusion pressure (CPP) values were decreased (2.8 times; p < 0.001) and increased (56%; p < 0.001), respectively, as compared to control preparations. These events were also associated with a considerable impairment of the cardiac tissue to generate 6-keto-PGF1 alpha. Treatments of rats with different doses of acetylcysteine (N-acetylcysteine, CAS 616-91-1, NAC; 0.25-0.5-1 g/kg p.o.) before HBO displayed a clear-cut and dose-related protective activity in hearts subjected to ischemia-reperfusion. Also the generating capacity of 6-keto-PGF1 alpha from these hearts were restored according to the dose of NAC employed. When aortic rings from rats exposed to HBO were considered, they showed a reduced capacity to release 6-keto-PGF1 alpha and an increased sensitivity to endothelin-1. At the same time, the relaxant activity of acetylcholine in these tissues was almost lost. Again, NAC treatment of the animals before HBO restored in a dose-dependent way the capacity of the aortic rings to generate 6-keto-PGF1 alpha. This event was paralleled by normalized responses of the preparations to endothelin-1 and acetylcholine. Taken together these results clearly indicate that acute HBO treatment of the rats markedly aggravates the ischemic-reperfusion damage in ex vivo hearts. This event is coupled with a compromised integrity of cardiac and extracardiac endothelial cell functions. The protective activity of NAC observed in this study once more emphasises its therapeutic role in increasing antioxidant defence mechanisms.

Hyperbaric oxygen worsens myocardial low flow ischemia-reperfusion injury in isolated rat heart

In these experiments rats were exposed to hyperbaric oxygen (100% oxygen; 2.5 atmospheres absolute pressure) for 1, 3 or 6 h. At the end of these periods the hearts were removed and subjected to low flow ischemia (perfusion rate from 12 ml/min to 2 ml/min for 40 min) and reperfusion. Hearts excised from control rats were subjected to the same procedure of ischemia and reperfusion. The data obtained from these experiments clearly indicate that the ischemic picture observed in control hearts is worsened in hearts obtained from hyperbaric oxygen-exposed animals. In fact, after ventricular standstill of the ischemic phase, the left ventricular end-diastolic pressure increased significantly and proportionally according to the time of hyperbaric oxygen exposure. The vasopressor activity of angiotensin II on coronary perfusion pressure was significantly changed, as compared to that in the control preparation: these alterations, well correlated to the time of hyperbaric oxygen exposure, seem to suggest impairment of the vascular endothelium-dependent relaxant function. Furthermore N-acetylcysteine and defibrotide, given orally to the rats before hyperbaric oxygen exposure, prevented the aggravation of the ischemic damage induced in ex vivo hearts.

Vitamin E nutritional status and serum lipid pattern in normal weanling rabbits

In a 6-wk postweaning trial (Trial 1), 30 male New Zealand White rabbits were fed a starter diet with three different levels of all-rac-alpha-tocopheryl acetate (60, 160, or 260 mg/kg diet). Plasma concentrations of alpha-tocopherol and serum concentrations of total cholesterol, high density lipoprotein (HDL) cholesterol, and triglycerides were measured at 2, 4, and 6 wk. In a 20-wk postweaning trial (Trial 2), 48 male New Zealand White rabbits were divided into two groups; one group was fed a vitamin E-free diet, and the other was fed the same diet supplemented with 60 mg/kg of all-rac-alpha-tocopheryl acetate. Plasma concentrations of alpha-tocopherol and serum total cholesterol, HDL cholesterol, and triglycerides were measured at 2, 4, 6, and 20 wk. In Trial 1, split-plot ANOVA showed that dietary all-rac-alpha-tocopheryl acetate increased plasma alpha-tocopherol (P < .01); in addition, serum total cholesterol and triglycerides declined more rapidly (P < .01) and HDL cholesterol increased more rapidly (P < .005) in rabbits fed supplemental all-rac-alpha-tocopheryl acetate than in controls. The all-rac-alpha-tocopheryl acetate intake was significantly correlated with serum total cholesterol reduction and HDL cholesterol increase only when plasma alpha-tocopherol was relatively low (< 23.5 mumol/ L). In trial 2, the vitamin E-free diet caused an increase (P < .05) in total serum cholesterol and a reduction in HDL cholesterol (P < .05 at 6 wk and P < .01 at 20 wk). The overall results of this study suggest that vitamin E plays an important role in the regulation of serum concentrations of cholesterol and lipoproteins in weanling rabbits. Consequently, the maintenance of an adequate nutritional status of vitamin E in the postweaning period is important to avoid alterations of serum lipid pattern.

Elective conservative surgery for renal carcinoma versus radical nephrectomy: a prospective study

OBJECTIVE

To identify criteria with which to select candidates for conservative nephrectomy, and to compare the results of radical and conservative nephrectomy in two homogeneous groups of patients with renal carcinoma, in a prospective study.

PATIENTS AND METHODS

Forty patients (27 men and 13 women, mean age 49.9 years, range 23-76) with renal carcinoma (T1-T2 NOMO, < 4 cm in diameter) were enrolled in the study between 1988 and 1993 and followed for a maximum of 98 months (mean 70.1). The patients were divided into two groups: Group A comprised 19 patients (mean age 51.4, SD 13.7 years, mean tumor size 3.34, SD 0.64 cm) who underwent partial nephrectomy: Group B comprised 21 patients (mean age 48.7, SD 14.7 years, mean tumour size 3.21, SD 0.56 cm) who were selected for radical nephrectomy. The survival and progression of disease were assessed.

RESULTS

Survival did not differ between the groups; one patient from each group died from distant metastases. There were no cases of local recurrence and multifocal neoplastic lesions were found in one patient during surgery.

CONCLUSION

This prospective study confirms the results of retrospective studies that conservative surgery is as effective as radical surgery for renal carcinoma; however, its clinical application is limited by the risk that the renal carcinoma is multifocal.

Adjunctive systemic hyperbaric oxygen therapy in treatment of severe prevalently ischemic diabetic foot ulcer. A randomized study

OBJECTIVE

To evaluate the effectiveness of systemic hyperbaric oxygen therapy (s HBOT) in addition to a comprehensive protocol in decreasing major amputation rate in diabetic patients hospitalized for severe foot ulcer.

RESEARCH DESIGN AND METHODS

From August 1993 to August 1995, 70 diabetic subjects were consecutively admitted into our diabetologic unit for foot ulcers. All the subjects underwent our diagnostic-therapeutic protocol and were randomized to undergo s-HBOT. Two subjects, one in the arm of the treated group and one in the arm of nontreated group, did not complete the protocol and were therefore excluded from the analysis of the results. Finally, 35 subjects received s-HBOT and another 33 did not.

RESULTS

Of the treated group (mean session = 38.8 +/- 8), three subjects (8.6%) underwent major amputation: two below the knee and one above the knee. In the nontreated group, 11 subjects (33.3%) underwent major amputation: 7 below the knee and 4 above the knee. The difference is statistically significant (P = 0.016). The relative risk for the treated group was 0.26 (95% CI 0.08-0.84). The transcutaneous oxygen tension measured on the dorsum of the foot significantly increased in subjects treated with hyperbaric oxygen therapy: 14.0 +/- 11.8 mmHg in treated group, 5.0 +/- 5.4 mmHg in nontreated group (P = 0.0002). Multivariate analysis of major amputation on all the considered variables confirmed the protective role of s-HBOT (odds ratio 0.084, P = 0.033, 95% CI 0.008-0.821) and indicated as negative prognostic determinants low ankle-brachial index values (odds ratio 1.715, P = 0.013, 95% CI 1.121-2.626) and high Wagner grade (odds ratio 11.199, P = 0.022, 95% CI 1.406-89.146).

CONCLUSIONS

s-HBOT, in conjunction with an aggressive multidisciplinary therapeutic protocol, is effective in decreasing major amputations in diabetic patients with severe prevalently ischemic foot ulcers.

Diagnostic value of various serum antibodies detected by diverse methods in childhood celiac disease

The diagnostic performances of antiendomysium IgA detected on monkey esophagus and human umbilical cord smooth muscle, of antireticulin IgA, and of antigliadin IgA and IgG were calculated in 74 children with celiac disease (CD) or other gastrointestinal disorders. We also compared four methods for gliadin antibody detection. With a diagnostic specificity of 100%, diagnostic sensitivity was 94% for antireticulin IgA, 93% for antiendomysium IgA when detected on human umbilical cord smooth muscle, and 97% when detected on monkey esophagus. The diagnostic sensitivity for gliadin antibody was highest with an ELISA procedure, followed by fluorogenic detection (94% for IgG, 91% for IgA, 97% with IgA and IgG combined). Because of its high diagnostic sensitivity and ease and speed of use, the combined antigliadin IgG and IgA antibody assay is suitable for screening large groups of patients. In IgG- or IgA-positive cases, the more demanding and more specific antiendomysium IgA evaluation is required to confirm suspected CD.

Diagnostic value of various serum antibodies detected by diverse methods in childhood celiac disease

The diagnostic performances of antiendomysium IgA detected on monkey esophagus and human umbilical cord smooth muscle, of antireticulin IgA, and of antigliadin IgA and IgG were calculated in 74 children with celiac disease (CD) or other gastrointestinal disorders. We also compared four methods for gliadin antibody detection. With a diagnostic specificity of 100%, diagnostic sensitivity was 94% for antireticulin IgA, 93% for antiendomysium IgA when detected on human umbilical cord smooth muscle, and 97% when detected on monkey esophagus. The diagnostic sensitivity for gliadin antibody was highest with an ELISA procedure, followed by fluorogenic detection (94% for IgG, 91% for IgA, 97% with IgA and IgG combined). Because of its high diagnostic sensitivity and ease and speed of use, the combined antigliadin IgG and IgA antibody assay is suitable for screening large groups of patients. In IgG- or IgA-positive cases, the more demanding and more specific antiendomysium IgA evaluation is required to confirm suspected CD.

Differential diagnosis between hepatocellular carcinoma and cirrhosis through a discriminant function based on results for serum analytes

We applied a multivariate analysis to a large series of serum biochemical tests in an attempt to identify a function that could efficiently discriminate cirrhosis from hepatocellular carcinoma (HC). We analyzed two successive temporal cohorts (1987-90; 1991-94) of HC and cirrhotic patients, all histologically classified (first cohort: 69 cirrhosis and 39 HC; second cohort: 66 cirrhosis and 38 HC). Using data from the first temporal cohort of patients, we obtained a discriminant function based on seven serum analytes: alpha-fetoprotein, the hepatic isoenzyme of alkaline phosphatase, lactate dehydrogenase isoenzyme 5, total gamma-glutamyltransferase (GGT), GGT isoforms complexed with low-density lipoprotein, aspartate aminotransferase, and copper. The same panel of analytes emerged when the second cohort was tested and also when both cohorts were tested together. In the two successive cohorts (total, 212 patients) with a prevalence of cirrhosis vs HC of approximately 2:1, the discriminant function correctly classified 93% of cases, the highest percentage of correct classification of the two diseases obtained so far by laboratory approaches. Validation with the jackknife reallocation statistical algorithm confirmed these results. In addition, of six patients with liver cirrhosis for whom we had the opportunity of following up and observing the evolution to HC, five were classified as HC at diagnosis by the multivariate discriminant analysis; i.e., discriminant analysis provided a diagnostic lead time of 6-12 months over histology. This discriminant function, based on easy-to-perform serum biochemical tests, may help solve a fundamental problem of differential diagnosis in the evolution of chronic liver diseases from cirrhosis to HC.

Pseudouridine and 1-ribosylpyridin-4-one-3-carboxamide (PCNR) serum concentrations in human immunodeficiency virus type 1-infected patients are independent predictors for AIDS progression

A prospective study was conducted with 161 human immunodeficiency virus (HIV)-positive patients to investigate the prognostic role of 10 serum-modified nucleosides with regard to some of the most widely used parameters of AIDS progression. Serum concentrations of pseudouridine (> 3.77 nmol/mL) predicted progression to AIDS in CDC stage A2 HIV-infected patients much better than did other widely used parameters (hazard ratio, 2.7; 95% confidence interval, 1.29-6.35; P = .01; median permanence time in stage A2, 17 vs. 30.5 months; P = .03). Serum concentrations of 1-ribosylpyridin-4-one-3-carboxamide (PCNR) and beta 2-microglobulin and the CD4:CD8 cell ratio, in decreasing order and used in combination, differentiated the overall survival time probability of AIDS patients; PCNR was the best and a new independent predictor (overall survival time, > 31 months, no positive parameters; 19.3 months, one positive parameter; and 5.5 months, two positive parameters.

From low hematocrit physiology to isovolemic hemodilution

The aim of this study, starting from some concepts of physiology, was to deal with the ever growing question of intentional anemia. Physiology suitably expresses the linear relationship between hematocrit and blood fluidity, and at the same time explains how viscosity and aggregability are important co-factors in the circulation, in disease and in thromboembolic complications. The need to understand how a low hematocrit level, compared to the volemia, is a fundamental requirement in surgery, and even more so in surgery with a high risk of embolism, like orthopedic traumatology surgery. Normovolemic hemodilution was analyzed both for the risks it involves and for how much it sticks to the changes induced by a similar situation on the various organs and apparatus. The authors, based on their experience in the field of anesthesiology, propose an operating schedule to safely perform intentional normovolemic hemodilution, describing the preoperative, intraoperative and finally the postoperative period. In conclusion, the authors advocate a wider use of this technique, confirming its safety in relation to volemia.

Discriminant function based on serum analytes differentiates hepatocarcinoma from secondary liver neoplasia

Hepatocellular carcinoma (HC) is often difficult to distinguish from secondary liver neoplasia (SLN) by physical and imaging diagnostic procedures alone. To this aim we have extended and improved a laboratory approach based on a serum lactate dehydrogenase isoenzyme ratio (LD4:LD5) by adding the carcinoembryonic antigen: alpha-fetoprotein ratio, alkaline phosphatase, and serum iron concentrations to obtain a highly efficient discriminant function. In two successive cohorts, for a total of 102 patients, all histologically diagnosed, with a prevalence of HC vs SLN of 3:1, we correctly classified 96% of cases (100% of SLN cases). Subsequent verification with the jackknife reallocation statistical algorithm confirmed these results. In conclusion, this discriminant function based on simple laboratory assays of a few analytes is an important tool in solving a diagnostic dilemma in cases of liver neoplasia.

Discriminant function based on serum analytes differentiates hepatocarcinoma from secondary liver neoplasia

Hepatocellular carcinoma (HC) is often difficult to distinguish from secondary liver neoplasia (SLN) by physical and imaging diagnostic procedures alone. To this aim we have extended and improved a laboratory approach based on a serum lactate dehydrogenase isoenzyme ratio (LD4:LD5) by adding the carcinoembryonic antigen: alpha-fetoprotein ratio, alkaline phosphatase, and serum iron concentrations to obtain a highly efficient discriminant function. In two successive cohorts, for a total of 102 patients, all histologically diagnosed, with a prevalence of HC vs SLN of 3:1, we correctly classified 96% of cases (100% of SLN cases). Subsequent verification with the jackknife reallocation statistical algorithm confirmed these results. In conclusion, this discriminant function based on simple laboratory assays of a few analytes is an important tool in solving a diagnostic dilemma in cases of liver neoplasia.

Blood saving program: a multicenter Italian experience

To assess the causes of failure in a blood saving program and the consequent need for homologous transfusions during major orthopedic surgery, data were collected from six orthopedic centers where an autotransfusion program was carried out from 1992-1994. The 1,576 (1,016 female and 560 male) patients studied (average age 63.6 +/- 10 years) were treated either for total hip prosthesis (1,144 pts) total knee prosthesis (212 pts), plate and screw removal plus hip prosthesis (8 pts), hip revision (cup 48 pts, stem 10 pts, cup plus stem 146 pts) and total knee revision (8 pts). Ninety percent of patients did not undergo homologous transfusions, which was significantly connected to: male sex (8% versus 11.7% p = 0.02), younger age (63.2 vs 66.9 years, p = 0.0001), higher weight (male 76 vs 70.7 Kg. p = 0.003, female 65.6 vs 61.9 Kg. p = 0.0003); higher baseline Hb (13.9 vs 12.8 g/dl, p = 0.0041), shorter operation time (110 vs 128 minutes, p = 0.0001); use of indobufen for antithromboembolic prophylaxis (indobufen 4.6% vs heparin calcium 15.2% vs low molecular weight heparin 9% p = 0.0001). On the contrary, the factors favoring homologous transfusions were: peripheral anesthesia (spinal and epidural 15.3% vs general 9.3% vs integrated 9.8% p = 0.016), total hip or knee revision, fixation device removal before hip prosthesis, systemic hypertension and coronary heart disease.

Assessment of visual contrast sensitivity in hyperbaric oxygen

Hyperbaric oxygen therapy is used in ophthalmology in ischemic pathologies of the anterior and posterior segments. Our experiment was done on a healthy group of volunteers aged between 10 and 50 yr. We examined the subject's vision before and after acute HBO exposure (60 min at 2.5 atm abs with pure oxygen) to verify whether vasoconstriction induced by hyperoxemia can influence eyesight. We measured the psychophysical determination of the threshold contrast according to Maione-Maffei's zebra test. The results demonstrated that contrast sensitivity is significantly improved for almost all the studied frequencies in normal subjects after acute HBO exposure. We hypothesize that the visual system has a reserve which is activated by an improvement of retinal oxygenation.

[Consensus conference. Saving blood: which are still the doubts and the problems?]

The consensus conference on blood saving has allowed us to formulate some interesting guidelines. The autologous and homologous transfusion require the patient's consent. For volemic replacement crystalloid solutions are used for phlebotomies below 10-15%, and colloid solutions for those greater than 10-15% of the blood mass. Severe isovolemic hemodilution (Ht < 20%) necessitates the reduction of the dosage of some drugs. A limit of Hb around 9 g/dl after phlebotomy may be acceptable in the absence of cerebral and coronary vascular disease. Phlebotomies are therefore possible also when the Hb values are 10 g/dl (Ht 30%). Hb values around 7 g/dl in the late postoperative period (from day 3 to 6) may be accepted only if well tolerated. The blood salvaged during surgery and at the beginning of the postoperative phase must always be centrifugated, washed and microfiltered. Subsequently, in the first 8 hours it is possible to reinfuse red cells after sedimentation and microfiltration. The techniques of predeposit, hemodilution and recovery are valid especially if associated with careful control of postoperative bleeding by means of aspiration under controlled pressure (at minimum negative values and sometimes positive ones), monitoring of blood loss from drainage and application of elastic compression bandages.

Total discrimination of peritoneal malignant ascites from cirrhosis- and hepatocarcinoma-associated ascites by assays of ascitic cholesterol and lactate dehydrogenase

No laboratory test completely distinguishes malignant ascites (MA) from ascites associated with cirrhosis and (or) hepatocellular carcinoma (A/C-HC). Ascitic cytology is highly specific but has a diagnostic sensitivity of only 40-60%. We determined 11 ascitic analytes and cytology in 58 patients with cirrhosis, 15 with hepatocellular carcinoma, and 21 with MA (10 ovarian cancers, 4 mesotheliomas, 6 gastrointestinal neoplasias, 1 leukemia). Ascitic total protein, cholesterol, pseudouridine, and lactate dehydrogenase (LD), and the ascitic:serum ratios of total protein and of LD showed the most significant differences between the two groups of patients. Stepwise multiple linear discriminant analysis (applying the Wilks' lambda criterion) of several variables, corroborated by the "jack-knife" reallocation procedure, showed that the ascitic cholesterol and ascitic LD association correctly identified 100% of MA and A/C-HC; cytology had a diagnostic specificity of 100%, but identified only 48% of MA. This association may represent a primary tool for the discrimination of ascites of unknown origin, particularly in the presence of negative cytology findings.

Total discrimination of peritoneal malignant ascites from cirrhosis- and hepatocarcinoma-associated ascites by assays of ascitic cholesterol and lactate dehydrogenase

No laboratory test completely distinguishes malignant ascites (MA) from ascites associated with cirrhosis and (or) hepatocellular carcinoma (A/C-HC). Ascitic cytology is highly specific but has a diagnostic sensitivity of only 40-60%. We determined 11 ascitic analytes and cytology in 58 patients with cirrhosis, 15 with hepatocellular carcinoma, and 21 with MA (10 ovarian cancers, 4 mesotheliomas, 6 gastrointestinal neoplasias, 1 leukemia). Ascitic total protein, cholesterol, pseudouridine, and lactate dehydrogenase (LD), and the ascitic:serum ratios of total protein and of LD showed the most significant differences between the two groups of patients. Stepwise multiple linear discriminant analysis (applying the Wilks' lambda criterion) of several variables, corroborated by the "jack-knife" reallocation procedure, showed that the ascitic cholesterol and ascitic LD association correctly identified 100% of MA and A/C-HC; cytology had a diagnostic specificity of 100%, but identified only 48% of MA. This association may represent a primary tool for the discrimination of ascites of unknown origin, particularly in the presence of negative cytology findings.

Simultaneous evaluation of vitamins A and E in human plasma by normal phase HPLC

The production of toxic oxidants such as H2O2; OH. and O2.- which follows aerobic metabolism is highly enhanced in aging, alcohol consumption and in a variety of degenerative diseases including neoplasias. Among the different antioxidant agents that in human organisms counterbalance the oxidative stress, which damages lipid, protein and DNA, are included beta-carotene, alpha-tocopherol, glutathione, ascorbate, ubiquinol and specific enzymes such as superoxide dismutase, catalase and glutathione peroxidase. In particular, vitamins A and E are the most important lipid-soluble antioxidants in human tissues protecting polyunsaturated fatty acid from peroxidation. In this paper we report an improved method, obtained after modification of a normal phase HPLC method, which allows the simple and rapid simultaneous evaluation of vitamins A and E in plasma. The separation of vitamins is achieved by eluting the HPLC column with a linear gradient from 1 to 5% isopropanol in n-hexane. The eluate is simultaneously monitored by U.V. and fluorescence detection to identify and quantify vitamins A and E, respectively.

Reference Intervals for Eight Modified Nucleosides in Serum in a Healthy Population from Italy and the United States

We used a recently devised HPLC method to quantify eight modified nucleosides, an emerging group of tumor markers, in human serum and then calculated their reference intervals in a healthy population from Italy and the United States. We used the statistical procedure of element analysis, which reveals the effects of chosen variables (in this case, nationality, sex, and age) on an analyte (here, modified nucleosides). Using element analysis, we calculated the exact weight of each variable on the reference values. We found that nationality has the greatest effect on the serum concentrations of all the modified nucleosides apart from pseudouridine, whereas sex significantly influences only the concentrations of 4-pyridone-3-carboxamide-N1-ribofuranoside, 1-methylinosine and N2,N2-dimethylguanosine; age affects only N2,N2-dimethylguanosine. Thus, the reference intervals of all the nucleosides except pseudouridine were calculated separately for Italians and Americans, and the reference values for 4-pyridone-3-carboxamide-N1-ribofuranoside, 1-methylinosine, and N2,N2-dimethylguanosine were calculated separately for men and women. Our data form the baseline for study of variations in serum concentrations of modified nucleosides in various pathophysiological conditions.

Reference intervals for eight modified nucleosides in serum in a healthy population from Italy and the United States

We used a recently devised HPLC method to quantify eight modified nucleosides, an emerging group of tumor markers, in human serum and then calculated their reference intervals in a healthy population from Italy and the United States. We used the statistical procedure of element analysis, which reveals the effects of chosen variables (in this case, nationality, sex, and age) on an analyte (here, modified nucleosides). Using element analysis, we calculated the exact weight of each variable on the reference values. We found that nationality has the greatest effect on the serum concentrations of all the modified nucleosides apart from pseudouridine, whereas sex significantly influences only the concentrations of 4-pyridone-3-carboxamide-N1-ribofuranoside, 1-methylinosine and N2,N2-dimethylguanosine; age affects only N2,N2-dimethylguanosine. Thus, the reference intervals of all the nucleosides except pseudouridine were calculated separately for Italians and Americans, and the reference values for 4-pyridone-3-carboxamide-N1-ribofuranoside, 1-methylinosine, and N2,N2-dimethylguanosine were calculated separately for men and women. Our data form the baseline for study of variations in serum concentrations of modified nucleosides in various pathophysiological conditions.