A monoclonal antibody (LYP18) directed against the blood platelet glycoprotein IIb/IIIa complex inhibits human melanoma growth in vivo

A monoclonal antibody (MoAb) (LYP18), generated against human platelet glycoprotein IIb/IIIa (GPIIb/IIIa), immuno-precipitated a IIb/IIIa-like GP complex from a highly tumorigenic human melanoma cell line (M3Dau). The M3Dau melanoma cells specifically bound 125I-labeled LYP18. To study the biologic role of these IIb/IIIa-like glycoproteins, M3Dau melanoma cells were incubated with LYP18 or a control MoAb directed against another melanoma cell-surface antigen and implanted subcutaneously (SC) in nude mice. LYP18 dramatically inhibited the growth of tumor in vivo. LYP18 was not directly cytotoxic to the melanoma cells. These results demonstrate that the IIb/IIIa-like GPs are present on melanoma cells and play a crucial role in tumor cell growth. MoAbs directed against tumor cytoadhesive receptors may represent a novel approach in tumor treatment.

[Surgery of the aortic arch in coronary patients. 400 surgically treated patients]

Out of 400 consecutive patients who underwent aorto-iliac surgery 45 (11.25 per cent) were known to have coronary disease at the time of the operation. Pre-operative coronary arteriography was carried out in the 11 patients (2.75 per cent) who had unstable or recently worsened angina. Aorto-coronary bypass was performed preventively in 7 patients (1.75 per cent of surgical patients). Mortality from preventive aorto-coronary bypass and secondary aorto-iliac surgery was nil. A study of post-operative mortality (2.75 per cent overall) showed that only one patient (0.25 per cent of surgical patients) died of myocardial infarction. The low rate of post-operative morbidity and mortality of coronary origin therefore does not incline to extend the indications for preventive aorto-coronary bypass. However, it seems desirable to improve the indications for pre-operative coronary arteriography by performing thallium 201 myocardial scintigraphy with dipyridamole infusion in all coronary patients about to undergo aorto-iliac surgery when no exercise electrocardiogram can be obtained because of intermittent claudication. This type of examination will probably broaden the indications for pre-operative coronary arteriography and preventive aorto-coronary bypass, though presumably to a very small extent. Among these 400 patients who underwent aorto-iliac surgery and were all followed up for 2 to 12 years, only a few (0.25 per cent) benefited secondarily from coronary surgery, no doubt because the physiological age of that population was often too high. In fact, these patients were mainly at risk of cancer aggravated by both alcohol and smoking, for in this study, and rather in contrast with most publications, cancer was responsible for 44 per cent of secondary deaths, i.e. more than twice the percentage (20 per cent) of secondary deaths of cardiac origin.

A multicentre evaluation of the Boehringer Mannheim/Hitachi 704 analysis system

The selective multitest Boehringer Mannheim/Hitachi 704 analysis system was examined according to the ECCLS guidelines in a multicentre evaluation involving four laboratories. Ten routine parameters, covering most of the application settings of the instrument, were measured in the respective laboratory at temperatures 25, 30 or 37 degrees C. The trial lasted four months and gave more than 40,000 data. It yielded the following results: 1. Within the four laboratories the mean coefficients of variation for three control sera at different concentrations were found to be equal to or better than 1.6% for the within-run imprecision and 2.8% or better for the between-day imprecision. 2. No drift was observed during eight hours. 3. Because of the high linear measuring range a re-run analysis was seldom necessary. 4. Sample-related carry-over was not seen. Reagent-dependent carry-over was measured from cholesterol to uric acid and from triacylglycerols to lipase. Through modification of the cholesterol and triacylglycerol reagents, the carry-over effect was practically eliminated. 5. The recovery of the assigned values of control sera showed average values between 99 and 104%. For bilirubin, creatinine, creatine kinase and alanine aminotransferase some control sera showed deviations greater than 10%. 6. In all cases, regression analysis of the results obtained in comparisons of the present instrument with the Hitachi 705 or 737 yielded slopes close to unity with extreme values of 0.95 and 1.06. 7. During the entire evaluation period there was no malfunction or breakdown of the instruments. The evaluators came to the conclusion that the analytical performance as well as the reliability and practicability of the Hitachi 704 can be rated as excellent.

Metastases of human tumors in experimental animals

A large variety of models of both artificial and spontaneous metastases have been developed in experimental animals. These models have enabled the characterization of metastatic cancer cells and have helped in understanding the metastatic process. Studies of experimental metastases of human tumors have so far been rather limited; these have been developed by xenografting human tumors in immuno-compromised animals, especially athymic nude mice. Although nude mice only seldom develop metastases when grafted with human tumor cells, the selection of human cancer cells with increased metastatic abilities could be obtained in a number of cases. Human melanoma variants and clones with increased metastatic abilities were obtained from melanoma cell lines in nude mice and in immunosuppressed newborn rats. Subcutaneous transplantation in a nude mouse of a human melanoma metastatic nodule resulted in a subcutaneous tumor (NTT) and in spontaneous lung (NTP) and lymph node (NTG) metastases which were first maintained in vivo by subcutaneous passages in nude mice and then cultured in vitro as cell lines. Cytogenetic studies showed that all three tumor lines have a common origin and that metastases resulted from a population selection. After 15 in vitro passages, NTP cells were reinjected s.c. in nude mice: serial transplantation was accompanied by an increase in metastatic abilities of tumor cells. Melanoma cell lines, tumorigenic but non metastatic in nude mice were xenografted to ATS-treated newborn rats. 3 weeks after s.c. injection of 10(6) cells, nearly all rats developed tumors and a proportion of them lung and lymph node metastases. Agar cloning of M4Beu line showed that it is heterogeneous and contains poorly tumorigenic but highly metastatic cells. In addition, serial in vivo passages resulted in the selection of highly tumorigenic but poorly metastatic cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Preliminary field observations on the flight speed of a phlebotomine sandfly

From observations with a portable wind tunnel used in the field in southern France, it is estimated that the maximum flight speed of Phlebotomus ariasi is in the range 0.65-0.70 m/sec (2.3 to 2.5 km/h).

Tumourigenic phenotypes of human melanoma cell lines in nude mice determined by an active antitumour mechanism

Ten human melanoma cell lines (HMCL) were tested for their ability to grow subcutaneously in nude mice. Using a standard inoculum, the HMCL could be characterized by their highly, fairly or poorly xenografting phenotype. These phenotypes were stable and the phenotype of one HMCL was recovered within cell clones derived from it. The role of nude mice natural defences in the expression of HMCL xenografting phenotypes was studied. Sublethal whole body irradiation and silica pretreatment of recipients enabled poorly tumourigenic HMCL to grow in most animals without affecting their splenic NK activity. Admixture of BCG or MDP encapsulated in liposomes with highly tumourigenic HMCL resulted in the abrogation of tumour growth in naive nude mice. The long lasting abrogating of NK activity in vivo by treatment with anti-asialo-GM1 anti-serum did not enhance the growth of a poorly tumourigenic HMCL. The HMCL were found to be resistant to in vitro murine NK activity. These results showed that the expression of the HMCL xenografting phenotypes could be controlled by the nude mice natural defences. NK cells did not seem to be largely involved whereas macrophages might be good candidates as anti-xenograft effectors.

Pyridoxal 5'-phosphate deficiency in uremic undialyzed, hemodialyzed, and non-uremic kidney transplant patients

In this study, we have investigated plasma pyridoxal 5'-phosphate (PLP) concentrations in undialyzed and dialyzed uremic patients and in kidney transplant subjects, using an enzymatic technique with thermal deproteinization to liberate PLP from plasma proteins. The specificity of the reaction indicates no interference with pyridoxal and only 3% interference with pyridoxamine phosphate. In 17 hemodialyzed patients, a deficiency of about 50% of plasma PLP concentration is found as compared to 25 healthy subjects (22.2 +/- 2.47 vs. 48.8 +/- 3.00 nmol . l-1), as mean +/- SEM). In seven undialyzed uremic patients with end-stage renal failure, the plasma PLP concentration is also decreased (29.3 +/- 1.74 nmol . l-1). The absence of PLP in plasma ultrafiltrates demonstrates that no loss of PLP occurs due to hemodialysis. The daily oral supplementation with 250-750 mg pyridoxal induces a supraphysiological increase in plasma PLP concentration in hemodialyzed as well as in undialyzed patients. In 116 non-uremic kidney transplant subjects, the mean plasma PLP concentration was 33.8 +/- 3.50 nmol . l-1). In 65% of these patients, a marked deficit (below 20 nmol . l-1) was observed. In conclusion, uremic patients have a deficient vitamin B6 state. Its correction with pyridoxal to restore physiological plasma PLP concentration necessitates oral supplementation with lower doses that those widely used at present. In kidney transplant patients a similar plasma PLP deficiency is observed in the absence of chronic renal failure.

A multicentre european evaluation of the Kodak EKTACHEM GLU/BUN analyzer using NCCLS guidelines and other approaches

This paper describes the field performance of the Kodak EKTACHEM GLU/BUN Analyzer for glucose and urea. NCCLS protocols PSEP-2, 3 an 4 were used which enable manufacturers to establish performance claims concerning the precision and accuracy of an analytical system. This multicentre trial used four analysers in four European countries, United Kingdom, France, West Germany and Italy to assess within and between laboratory performances. Freeze dried control materials were used for the performance check experiment PSEP-2 and for the replication experiment PSEP-3. The replication study, although very time consuming, was straight forward to undertake and the results were comparable between centres. Compliance with the protocol for comparison of methods experiment PSEP-4 in which laboratories used their own hospital patient samples was more difficult. The problems with obtaining suitable samples and the performance of comparative methods are discussed in detail.

[In vitro supplementation of pyridoxal phosphate for the optimisation of the determination of the catalytic activity of alanine aminotransferase and aspartate aminotransferase in kidney transplant patients (author's transl)]

Pyridoxal phosphate (PLP) is the coenzyme of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Thus, in vitro supplementation with PLP is important for the optimisation of the determination of catalytic activity of both enzymes. It patients with kidney transplants, stimulation by PLP is very important for ALT activity, which could be affected by plasma PLP deficiency. Furthermore, in this population catalytic activities are more frequently found increased using methods with PLP supplementation than without PLP supplementation (56% and 71% of patients for AST and ALT, respectively). These differences are not related to HBs antigen.

Enzymic measurement of urinary pyrophosphate with a centrifugal analyzer

We describe a simple, rapid, and fully automated technique for measuring urinary pyrophosphates with a centrifugal analyzer (the ENI GEMSAEC). This technique depends on the enzymic magnesium-dependent reaction with UDPG pyrophosphorylase (UTP: alpha-D-glucose-1-phosphate uridylyl transferase, EC 2.7.7.9) and spectrophotometry of the NADPH formed in a combined system of phosphorylation and reduction. Many samples of urine can be analyzed quickly without pretreatment, with high sensitivity (1.3 mA/mumol of substrate) and good reproducibility. The mean within-run coefficient of variation for a 50 mumol/L pyrophosphate solution was 1.4%. We determined the optimum enzyme and magnesium concentrations necessary for use in a 4-min reaction. Because there is no inhibitory effect of chloride and phosphate ions, pyrophosphate can be measured directly in urine, without prior extraction. With this technique, the mean value (and SD) for urinary pyrophosphate excretion by 30 healthy subjects was 39.3 (SD 17.2) mumol/24 h.

Suitability of control materials for determination of alpha-amylase activity

The suitability of control materials for determination of alpha-amylase activity was assessed in comparison with reference groups of authentic human serum specimens containing alpha-amylase of either pancreatic or salivary origin, specimens from patients with no pancreatic pathology, and normal specimens to which porcine pancreatic alpha-amylase was added. After determination of alpha-amylase activity by 11 commonly used techniques (five different principles), the results were processed by both classical (linear representation, regression) and multivariate (correspondence analysis, principal-components analysis) statistical techniques. Specimens containing porcine pancreatic alpha-amylase did not behave like any of the other groups. We conclude that porcine enzyme should not be used for interlaboratory quality-control surveys or intermethod comparison studies. Determination of human salivary and pancreatic alpha-amylase showed intermethod biases similar to those for authentic patients' specimens. Human salivary alpha-amylase, both because of its behavior and its commercial availability, is a satisfactory source for alpha-amylase activity of quality-control specimens. The nature of the matrix (polyvinylpyrrolidone, albumin, delipidated serum, bovine serum, or human serum) little influenced the behavior of the specimens for any of the methods studied.

Suitability of control materials. General principles and methods of investigation

We propose methods for characterizing the behavior of quality-control specimens. Candidate quality-control specimens and authentic patients' specimens were analyzed by various methods. Patients' specimens were chosen to be fully representative of those encountered, including subsets from persons who were healthy, had defined disease states, were in therapy, or whose specimens were lipemic, icteric, etc. The analytical methods chosen include those most commonly used as well as reference analytical methods. Procedures for characterizing the behavior of patients' specimens and candidate quality-control specimens are proposed and their applicability is demonstrated. The linear ratio method is a univariate graphical approach in which differences in accuracy among methods for any specimen or group of specimens are each displayed on a linear scale. Correspondence analysis is a descriptive multivariate statistical technique that allows both the specimens and the analytical methods to be characterized. The statistical techniques, in our application, allow the behavior of quality-control specimens to be assessed with respect to authentic patients' specimens without influencing the assessment process. Correspondence analysis provides a graphic representation by projecting both the specimens and the analytical methods on factorial planes. The appropriateness of te behavior of a quality-control specimen may be inferred from its position relative to those of authentic patients' specimens. These statistical techniques also provide some information regarding the specificity of analytical methods.

Suitability of control materials. General principles and methods of investigation

We propose methods for characterizing the behavior of quality-control specimens. Candidate quality-control specimens and authentic patients' specimens were analyzed by various methods. Patients' specimens were chosen to be fully representative of those encountered, including subsets from persons who were healthy, had defined disease states, were in therapy, or whose specimens were lipemic, icteric, etc. The analytical methods chosen include those most commonly used as well as reference analytical methods. Procedures for characterizing the behavior of patients' specimens and candidate quality-control specimens are proposed and their applicability is demonstrated. The linear ratio method is a univariate graphical approach in which differences in accuracy among methods for any specimen or group of specimens are each displayed on a linear scale. Correspondence analysis is a descriptive multivariate statistical technique that allows both the specimens and the analytical methods to be characterized. The statistical techniques, in our application, allow the behavior of quality-control specimens to be assessed with respect to authentic patients' specimens without influencing the assessment process. Correspondence analysis provides a graphic representation by projecting both the specimens and the analytical methods on factorial planes. The appropriateness of te behavior of a quality-control specimen may be inferred from its position relative to those of authentic patients' specimens. These statistical techniques also provide some information regarding the specificity of analytical methods.

Suitability of control materials for determination of alpha-amylase activity

The suitability of control materials for determination of alpha-amylase activity was assessed in comparison with reference groups of authentic human serum specimens containing alpha-amylase of either pancreatic or salivary origin, specimens from patients with no pancreatic pathology, and normal specimens to which porcine pancreatic alpha-amylase was added. After determination of alpha-amylase activity by 11 commonly used techniques (five different principles), the results were processed by both classical (linear representation, regression) and multivariate (correspondence analysis, principal-components analysis) statistical techniques. Specimens containing porcine pancreatic alpha-amylase did not behave like any of the other groups. We conclude that porcine enzyme should not be used for interlaboratory quality-control surveys or intermethod comparison studies. Determination of human salivary and pancreatic alpha-amylase showed intermethod biases similar to those for authentic patients' specimens. Human salivary alpha-amylase, both because of its behavior and its commercial availability, is a satisfactory source for alpha-amylase activity of quality-control specimens. The nature of the matrix (polyvinylpyrrolidone, albumin, delipidated serum, bovine serum, or human serum) little influenced the behavior of the specimens for any of the methods studied.

[Ecology of leishmaniasis in the south of France. -- 12. Horizontal dispersion of Phlebotomus ariasi Tonnoir, 1921. Preliminary experiments (author's transl)]

By use of mark-release-recapture methods, evidence was obtained of the distance of the dispersion of Phlebotomus ariasi Tonnoir, 1021. Female flies, collected in a valley in the Cévennes mountains (at Roquedur, Gard), were marked with fluorescnt powders, released an then recaptured by searching with ultra-violet lamps. The majority of the flies recapture were among ones given a blood meal shortly before release. Recaptures were made from the second day after release. A number of females migrated with blood in the midgut; their ovaries were up to and including stage V. The distance between the extreme points of recapture was about 1 km, and the maximum recorded distance between points of release and recapture was 750 m. The epidemiological interest of these observations is that, at least in the Cévennes foci, the sandfly as well as the dog must now be considered as capable spreading the pathogenic agent of visceral leishmaniasis.

[Ecology of leishmaniasis in the south of France. 11. Canine leishmaniasis: successful experimental transmission from dog to dog by the bite of Phlebotomus ariasi Tonnoir, 1921 (author's transl)]

As part of a study of visceral leishmaniasis in the Cévennes in southern France, an infection was transmitted from dog to dog by the bite of a single sandfly, Phlebotomus ariasi Tonnoir, 1921. The role of this species as a vector, suspected from earlier studies, is, therefore, confirmed. Twenty female sandflies, which had engorged on a naturally infected dog 23 +/- 2 days previously were put with a healthy dog which, after an incubation period of 15 months, developed viscero-cutaneous leishmaniasis. In dissections of the sandflies immediately after contact with the experimental dog, it was found that only one had engorged. All of 17 sandflies dissected had midgut infections: 10 of these also had infections in the pharynx. The engorged specimen additionally had parasites in the proboscis, a condition thought by many workers to be necessary for the parasite to be transmitted by bite.

Criteria for establishing a standardized method for determining alkaline phosphatase activity in human serum

We investigated factors influencing alkaline phosphatase activity in the course of developing criteria for the establishment of a standardized method for its determination in human serum at 30 degrees C. The effects of pH, phosphorylatable acceptor (2-amino-2-methyl-1-propanol and diethanolamine), 4-nitrophenyl phosphate, magnesium ion, zinc ion, temperature, volume fraction of specimen, and details of initiation of the reaction have been studied, with use of partly purified enzymes from bone, intestine, liver, and placenta, and sera from patients with a predominant characterized isoenzyme. The purity of the diethanolamine was examined and contaminant monoethanolamine was characterized as a competitive inhibitor. Two sets of recommended conditions are: 2-amino-2-methyl-1-propanol, 0.9 mol/liter; 4-nitrophenyl phosphate, 16 mmol/liter; magnesium ion, 1 mmol/liter; volume fraction of specimen 1/30, and pH30 degrees C 10.5; diethanolamine, 1.8 mol/liter; 4-nitrophenyl phosphate, 18 mmol/liter; magnesium ion, 1 mmol/liter; volume fraction of specimen 1/60, and pH30 degrees C 10.1. Serum is preincubated with all reagents but 4-nitrophenyl phosphate, which is used as the reaction-initiating substrate.

Criteria for establishing a standardized method for determining alkaline phosphatase activity in human serum

We investigated factors influencing alkaline phosphatase activity in the course of developing criteria for the establishment of a standardized method for its determination in human serum at 30 degrees C. The effects of pH, phosphorylatable acceptor (2-amino-2-methyl-1-propanol and diethanolamine), 4-nitrophenyl phosphate, magnesium ion, zinc ion, temperature, volume fraction of specimen, and details of initiation of the reaction have been studied, with use of partly purified enzymes from bone, intestine, liver, and placenta, and sera from patients with a predominant characterized isoenzyme. The purity of the diethanolamine was examined and contaminant monoethanolamine was characterized as a competitive inhibitor. Two sets of recommended conditions are: 2-amino-2-methyl-1-propanol, 0.9 mol/liter; 4-nitrophenyl phosphate, 16 mmol/liter; magnesium ion, 1 mmol/liter; volume fraction of specimen 1/30, and pH30 degrees C 10.5; diethanolamine, 1.8 mol/liter; 4-nitrophenyl phosphate, 18 mmol/liter; magnesium ion, 1 mmol/liter; volume fraction of specimen 1/60, and pH30 degrees C 10.1. Serum is preincubated with all reagents but 4-nitrophenyl phosphate, which is used as the reaction-initiating substrate.

Direct enzymatic determination of urea in plasma and urine with a centrifugal analyzer

A direct enzymatic micromethod (sample volume, 3mul) has been adapted to the centrifugal analyzer (ENI-GEMSAEC) for measurement of urea in plasma and urine. The method is based on urease (urea amidohydrolase, EC3.5.1.5)/glutamate dehydrogenase [l-glutamate:NAD(P)+oxidoreductase (deaminating), EC1.41.3] coupled reactions, and uses a two-point fixed-time (t(1)=20s,t(2)=50s)kinetic scheme for monitoring the rate of comsumption of NADH at 340 nm. Sensitivity and precision of the method are excellent,and results compare well with those from a commonly used continuous-flow method.

Direct enzymatic determination of urea in plasma and urine with a centrifugal analyzer

A direct enzymatic micromethod (sample volume, 3mul) has been adapted to the centrifugal analyzer (ENI-GEMSAEC) for measurement of urea in plasma and urine. The method is based on urease (urea amidohydrolase, EC3.5.1.5)/glutamate dehydrogenase [l-glutamate:NAD(P)+oxidoreductase (deaminating), EC1.41.3] coupled reactions, and uses a two-point fixed-time (t(1)=20s,t(2)=50s)kinetic scheme for monitoring the rate of comsumption of NADH at 340 nm. Sensitivity and precision of the method are excellent,and results compare well with those from a commonly used continuous-flow method.

[Mixed dacron-vein bypass. Apropos of 33 cases]

The use of a mixed dacron-vein by-pass is a technical device permitting one to palliate the impossibility of using exclusively venous material. 33 by-passes were thus carried out:--30 distal by-passes;--3 proximal by-passes. The interest of this technique is the possibility of implanting on a small caliber artery, e.g. profunda femoris, popliteal or femoral artery. The main technical point is the immediate anastomosis. Since this article was drawn-up, the indications for this procedure have been multiplied and, over a period of six months, we carried out 32 new mixed by-passes.--27 proximal by-passes;--5 distal by-passes.