[Mammary implant selection or chest implants fabrication with computer help]. / Apport de l'informatique à la sélection des implants mammaires ou à la fabrication sur mesure des implants thoraciques.

Authors present their personal and original experience in the use of computer to enhance the precision in the good choice of volumes and shapes in the field of mammary reconstruction and aesthetic augmentation (800 cases). Concerning funnel chest (163 cases) and Poland syndrome (12 cases), they use computer-assisted conception and custom-made implants, much more precise than traditional plaster cast.

Influence of the multidrug transporter inhibitors on the activity of Kv1.3 voltage-gated potassium channels.

Using the whole-cell patch-clamp technique, the influence of selected multidrug resistance modulators, both plant-derived compounds and derivatives on the activity of voltage-gated potassium channels Kv1.3 was investigated. Twelve compounds with phenolic and terpenic structures were tested: the stilbenes piceatannol (1) and its tetramethoxy (2) and tetracetoxy (3) derivatives, the flavonoids naringenin (4) and its methylated derivatives: naringenin-4',7-dimethylether (5) and naringenin-7-methylether (6), and aromadendrin (7), the coumarins esculetin (8) and scopoletin (9) and ent-abietane diterpenes, helioscopinolide B (10) and its 3beta-acetoxy derivative (11) and helioscopinolide E (12). The studies were performed on a model system with Kv1.3 channels endogenously expressed in human T lymphocytes. Obtained data provide evidence that compounds 2, 5 and 6 applied at 30 microM inhibited the amplitude of recorded currents to 31%, 4% and 29% of its control value, respectively. On the other hand, compounds 3, 4, 7-12 (at 30 microM) and compound 1 (at 40 microM) did not affect significantly the channel activity. These results indicate that some methoxy-derivatives of the tested compounds are effective inhibitors of Kv1.3 channels. Since the inhibition of Kv1.3 channels may inhibit the proliferation of prostate, breast and colon cancer cells expressing these channels, the channel inhibitors may exert an antiproliferative action. This action combined with a simultaneous modulation of the multidrug resistance may be significant for a potential application of these compounds in cancer chemotherapy.

The modulatory effect of zinc ions on voltage-gated potassium currents in cultured rat hippocampal neurons is not related to Kv1.3 channels.

We applied the whole-cell patch-clamp technique to study the influence of zinc ions (Zn(2+)) and extracellular protons at acidic pH (pH(o)) on voltage-gated potassium currents in cultured rat hippocampal neurons. The first goal of the study was to estimate whether Kv1.3 currents significantly contributed to voltage-gated potassium currents in examined cells. Then, the influence of both ions on the activity of other voltage-gated potassium currents in the neurons was examined. We examined both the total current and the delayed - rectifier component. Results obtained in both cases were not significantly different from each other. Available data argued against any significant contribution of Kv1.3 currents to the recorded currents. Nevertheless, application of Zn(2+) in the concentration range from 100 microM to 5 mM reversibly modulated the recorded currents. The activation midpoint was shifted by about 40 mV (total current) and 30 mV (delayed-rectifier current) towards positive membrane potentials and the activation kinetics were slowed significantly (2 - 3 fold) upon application of Zn(2+). The inactivation midpoint was also shifted towards positive membrane potentials, but less significantly (about 14 mV). The current amplitudes were reduced in a concentration-dependent manner to about 0.5 of the control value. The effects of Zn(2+) were saturated at the concentration of 1 mM. Raising extracellular proton concentration by lowering the pH(o) from 7.35 to 6.4 did not affect significantly the currents. Possible mechanisms underlying the observed phenomena and their possible physiological significance are discussed.

The inhibitory effect of copper ions on lymphocyte Kv1.3 potassium channels.

We applied the whole-cell patch-clamp technique to study the inhibitory effect of copper ions (Cu) on the activity of Kv1.3 channels expressed in human lymphocytes. Application of Cu reversibly inhibited the currents to about 10% of the control value in a concentration-dependent manner with the half blocking concentration of 5.28+/-0.5 microM and the Hill's coefficient of 3.83+/-0.18. The inhibitory effect was saturated at 10 microM concentration. The inhibition was time-dependent and it was correlated in time with a significant slowing of the current activation rate. In contrast the voltage dependence of activation was not changed by Cu as well as the inactivation kinetics. The inhibitory effect of Cu was voltage-independent. It was also unaffected by changing the extracellular pH in the range from 6.4 to 8.4, raising the extracellular potassium concentration to 150 mM and by changing the holding potential from -90 to -60 mV. The inhibitory effect of Cu was not changed in the presence of an equivalent concentration of Zn. Altogether, obtained data suggest that Cu inhibits Kv1.3 channels by a different mechanism than Zn and that Cu and Zn act on different binding sites. The inhibitory effect of Cu was probably due to a specific binding of Cu on binding sites on the channels. Possible physiological significance of the Cu-induced inhibition of Kv1.3 channels is discussed.

Influence of extracellular pH on the modulatory effect of zinc ions on Kv1.3 potassium channels.

In the present study we applied the whole-cell patch-clamp technique to study the influence of extracellular pH (pH(o)) on the modulatory effect exerted by zinc ions (Zn(2+)) on voltage-gated potassium channels Kv1.3 expressed in human lymphocytes. Obtained data provide evidence that lowering of pH(o) from the 7.35 to 6.4 slowed significantly the current activation rate, shifted the activation midpoint by about 16 mV towards positive membrane potentials and reduced the current amplitude to about 0.55 of the control value. In contrast, raising the pH(o) from 7.35 to 8.4 did not affect significantly the activation midpoint and current amplitude. Application of Zn(2+) in the concentration range from 100 microM to 1 mM at pH(o)=6.4 slowed additionally the activation rate, shifted the activation midpoint by about 20 mV towards positive membrane potentials and reduced the current amplitude in a concentration-dependent manner. The total effect exerted by Zn(2+) and protons at pH(o) = 6.4 was more significant than the effect exerted by Zn alone. Both the magnitude of the shift and the degree of current inhibition by Zn(2+) were independent on pH(o) in the range from 6.4 to 8.4. The data might suggest that the effects exerted by protons and zinc ions occur independently on each other and probably involve different mechanisms. Changing the holding potential from -90 mV to -60 mV at pH(o)=7.35 abolished the Zn(2+)-induced inhibition of the current amplitudes at concentrations below 300 microM. At pH(o)=6.4 the total inhibition caused by Zn(2+) and protons was also diminished, however, a significant reduction was observed at 100 microM concentration. In contrast, changing the holding potential did not change the Zn(2+)- and proton-induced shift of the activation midpoint. Altogether, obtained data suggest that extracellular protons exert the modulatory effects that are additive to the effects exerted by Zn(2+) on the channels. Possible physiological significance of these additive effects is discussed.

Genistein inhibits the activity of kv1.3 potassium channels in human T lymphocytes.

In the present study, the whole-cell patch-clamp technique was applied to follow the inhibitory effect of genistein--a tyrosine kinase inhibitor and a natural anticancer agent--on the activity of voltage-gated potassium channels Kv1.3 expressed in human T lymphocytes (TL). Obtained data provide evidence that genistein application in the concentration range of 1-80 microM reversibly decreased the whole-cell potassium currents in TL in a concentration-dependent manner to about 0.23 of the control value. The half-blocking concentration range of genistein was from 10 to 40 microM. The current inhibition was correlated in time with a significant decrease of the current activation rate. The steady-state activation of the currents was unchanged upon application of genistein, as was the inactivation rate. The inhibitory effect of genistein on the current amplitude and activation kinetics was voltage-independent. The current inhibition was not changed significantly in the presence of 1 mM of sodium orthovanadate, a tyrosine phosphatase inhibitor. Application of daidzein, an inactive genistein analogue, did not affect significantly either the current amplitudes or the activation kinetics. Possible mechanisms of the observed phenomena and their significance for genistein-induced inhibition of cancer cell proliferation are discussed.

The "patch-clamp" technique and its application in investigations of the properties of human T lymphocyte potassium channels.

The first part of this review presents a historical outline on the development of experimental methods in electrophysiology starting from the first experiments performed in the 1920s and ending with the "patch-clamp" technique. Recording configurations of the "patch-clamp" technique are briefly reviewed in the second section. The areas of application of the configurations are shown. The last section contains a short review on the available data of "patch-clamp" studies on the expression and properties of potassium channels in human T lymphocytes (TL). Problems that require further investigation are briefly presented.

[Regulation of potassium channel function in T lymphocytes by intracellular second messengers for calcium, cyclic AMP and membrane lipid metabolites]. / Regulacja funkcji kanalów potasowych w limfocytach T przez wewnatrzkomórkowe wtórne przekazniki na przykladzie wapnia, cyklicznego AMP oraz zwiazków lipidowych.

This review focuses on the influence of well-known intracellular second messengers on the activity of potassium channels expressed in human T lymphocytes. Basic biophysical properties of the channels are briefly presented. Available data on the regulatory role of intracellular calcium and cyclic AMP is reviewed. Finally, a possible influence of lipid compounds, especially high-density lipoproteins, lysophospholipids and sphingolipids, on the expression and activity of potassium channels in human T lymphocytes is discussed.

[The function of voltage-gated potassium canals in T-lymphocytes under physiological and pathologic conditions]. / Funkcja kanalów potasowych napieciowozaleznych w limfocytach T w stanie fizjologii i patologii.

This review focuses on biophysical properties and physiological role of voltage-gated potassium channels (named as Kv1.3) in T lymphocytes. In the first section basic electrophysiological and pharmaceutical properties of the channels have been described. Then the data on the role of the channels in setting the cell resting membrane potential, cell mitogenesis and volume regulation has been reviewed. Finally, results on patch-clamp studies on the changes in the channel expression in TL in patients suffering from chronic renal failure have been presented.

[A rare mediastinal-hilar pseudotumor: esophageal and azygos vein varices]. / Une pseudotumeur médiastino-hilaire rare: varices oesophagiennes et azygos.

Mediastinal pseudotumors are present in less than 5% of patients with long-standing portal hypertension. These pseudotumors may be caused by para-esophageal collateral vessels or greatly dilated azygos or hemiazygos veins. Enhanced CT seems to be the best tool for the diagnosis and in evaluating the overall status of portosystemic collateral vessels. In this case report, MRI ruled out tissular mass by showing vascular signal.

[Postpartum cerebral angiopathy of iatrogenic origin]. / Angiopathie cérébrale du post-partum d'origine iatrogène.

A 30 year old women, beginning her 19th day postpartum, was admitted for lowering of alertness. The day before she complained of cephalalagia. Neurologic examination showed pyramidal tract signs on the right part of the body, a bilateral Babinski sign, and central oculomotor palsy. She started a treatment by nasal pulverization of phenylephrine, a sympathomimetic vasoconstrictor, one week before, and took bromocriptine (5 mg per day) from childbirth to second week postpartum. CT scan was normal. Lumbar puncture showed a high level of proteins, from transsudative origin. Cerebral angiography showed a beading aspect of arterial branches, especially in the left middle cerebral artery territory. Two days after drug withdrawal, the patient recovered. This angiographic pattern has already been described in cases of cerebral angiopathy due to sympathomimetic drug abuse, and in cases of postpartum cerebral angiopathy. The chronology, in our case, makes the responsibility of the phenylephrine very likely. Nonetheless, ergot derivatives (i.e. ergonovine, bromocriptine) have also been accused of giving cerebral postpartum angiopathy. In our case, we think that bromocriptine may have triggered the cerebral angiopathy due to phenylephrine.

Propofol blocks voltage-gated potassium channels in human T lymphocytes.

The effect of propofol (PR) on voltage-gated potassium channels (KV) in human T lymphocytes (TL) was studied using the patch-clamp technique in the whole-cell configuration. PR was found to reversibly block the KV channels in a dose-dependent manner with a half-blocking concentration of approximately 40 microM. The decrease in the peak current caused by PR was voltage-independent. The activation time constant of the whole-cell potassium currents remained unaffected upon PR treatment, whereas both the rate and extent of the inactivation process were increased, indicating the "open channel block" mechanism. The PR half-blocking concentration was of the same order of magnitude as PR blood concentrations employed in anesthesia. Taking into account the extensive use of PR and the important role of KV channels in human TL, these results suggest a need for investigations into the effect of PR on TL cell-function regulation.

Patch-clamp study on T-lymphocyte potassium conductance in patients with chronic renal failure.

Using the patch-clamp technique, we studied the differences in whole-cell potassium conductance (g(K)+) in T lymphocytes (TL) from three groups of patients suffering from renal failure: not dialyzed patients, dialyzed patients, and dialyzed patients treated with human recombinant erythropoietin (rHuEPO). The differences in g(K+) values in the group of not dialyzed patients in comparison with controls was not significant (p > 0.05). In the group of dialyzed patients, after roughly 6 years of the hemodialysis therapy, the g(K+) value was significantly higher than in controls. In dialyzed patients treated with rHuEPO, g(K+) value was significantly lower in comparison with control. Moreover, in dialyzed patients treated with rHuEPO, the time duration of dialysis therapy did not significantly affect the TL whole-cell conductance. We conclude that the g(K+) is changed in TL in renal failure patients and that the time duration of hemodialysis therapy as well as the use of rHuEPO affect the g(K+) value. Possible mechanisms underlying the observed changes in g(K+) values, as well as medical implications of obtained results are discussed.

[Magnetic resonance imaging of the knee. 3 cases of pigmented villonodular synovitis]. / Imagerie par résonance magnétique du genou. 3 cas de synovite villonodulaire pigmentée.

Pigmented villonodular synovitis is a benign monoarticular synovial proliferative disorder. Three cases involving the knee are reported. MR signs are highly suggestive: --joint effusion (blood); --hypointense synovial proliferation (irregular infrapatellar fat pad sign; hemosiderin deposits); --no loss of joint space. Diagnosis by MR Imaging is early, accurate and atraumatic.

[Malignant lymphomas in Burgundy, France (1976--1977): a new approach using computerized pathological diagnoses (author's transl)]. / Les lymphomes malins en Bourgogne (1976--1977). Etude de leur fréquence par la méthode informatique anatomopathologique.

Pathology laboratories in the Burgundy region have recently been equipped with mini-computers using the same software and working method. This report brings together their histological records, stored on magnetic discs, and describes the first results of this regional data base. Malignant lymphomas were chosen as a pilot study and evaluated between January 1976 and December 1977. After a brief presentation of the method, 246 cases of malignant lymphoma are analysed: 95 of Hodgkins disease, 103 of non-Hodgkins malignant lymphoma of the nodes and 48 cases of extranodal non-Hodgkins malignant lymphoma. The distribution of patients in terms of sex and ten year age groups is analysed, together with the various incidence rates for a year in Burgundy and in its four administrative units (Cote-d'Or, Nievre, Saone-et-Loire and Yonne).