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Query: UMLS:C0019829 (Hodgkin's disease)
 30,247 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Experience with the use of external beam conventional radiation over a period of several decades has shown that in every instance where there has been a major advance in the physical delivery of radiation to the tumor (beam energy and characteristics and precise tumor dose delivery) there has been a corresponding major improvement in the treatment results. The advent of megavoltage sources following the invention and use of Cobalt 60 and medical linear accelerator units during the late 1940's and early 1950's and their major impact on tumor control and patient survival in solid tumors such as carcinoma of the prostate, Hodgkin's Disease, head and neck tumors and cancer of the cervix are being discussed. Most recently, the use of computerized tomography and computer systems for treatment planning is likely to show a further improvement in the therapeutic results.
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PMID:Does improved depth dose characteristics and treatment planning correlate with a gain in therapeutic results? Evidence from past clinical experience using conventional radiation sources. 174 Mar 90

1. The patch-clamp method was applied to the study of ionic currents activated by depolarization of undifferentiated IMR-32 human neuroblastoma cells. Whole-cell sodium and potassium currents and single potassium ion channel currents from cell-attached patches were investigated. 2. Cells had a mean resting potential of -38 mV and mean input resistance of 1.6 G omega. Single action potentials were evoked under current clamp during the injection of depolarizing currents. 3. A voltage-dependent inward sodium current was observed which reversed at +44 mV. A Boltzmann fit to the activation curve gave a half-maximal activation voltage of -41.6 mV and a 'slope' of 3.9 mV. The steady-state inactivation curve had a half-maximal inactivation voltage of -81 mV and a 'slope' of 9.7 mV. 4. The time-dependent activation and inactivation of the current displayed classical Hodgkin-Huxley kinetics. Values for the time constants tau m and tau h of 0.16 and 0.63 ms were calculated for a voltage jump from -80 to -10 mV; tau m and tau h decreased as the step potential was changed from -30 to +20 mV. 5. Outward currents were activated in bathing solutions substantially free of anions and could thus be attributed to potassium ions. The tail current reversed in direction on repolarization to -60 mV when the potassium concentration in the bathing solution was increased from 6 to 30 mM. When the bathing solution contained 145 mM-potassium, and the patch pipette, 95 mM, a depolarization to -10 mV from a holding potential of -60 mV evoked an inward current. 6. Outward currents were examined by using voltage pulses which depolarized the cell to -20 mV, or more positive values, from a holding potential of -80 mV and by pulses which depolarized the cell to 0 mV, or to positive values, from a holding potential of -30 mV. A Boltzmann fit of typical activation data gave a half-maximal activation voltage of 17 mV and a 'slope' of 14 mV. 7. The time course of the rising phase of the current was described by a function of the form A(1-exp[-(t-delta t)/tau]), where delta t varied between 1 and 4 ms and tau varied between 4 and 27 ms, decreasing with increasing depolarization. There was no evidence for a fast transient component. 8. The amplitude of outward currents was reduced by extracellular calcium ions, cobalt ions, tetraethylammonium and 4-aminopyridine.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:On the sodium and potassium currents of a human neuroblastoma cell line. 202 15

Between 1983 and 1987, we treated 16 patients with Hodgkin's disease, according to a post-COPP and a post-ABVD protocol, respectively. All patients had received previous treatment, including megavoltage cobalt radiotherapy, and were in advanced stages of disease, mostly with immunosuppression/immune deficiency. The protocol of lomustine, etoposide, adriamycin, methotrexate and prednisolone was commenced after the above therapy had failed or was not tolerated. Compared to the previously used chemotherapy, the 3 new cytotoxic agents were well tolerated. A complete remission was obtained in 4 patients and a partial remission in 9. In 2 patients, there was a temporary partial remission only. In more than half the patients, a positive effect on the clinical course was recorded. Viewed as a whole, a favourable objective and subjective result ensued. This LEAMP second-line protocol was found to be effective and well tolerated.
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PMID:[Experiences with a new second-line protocol in the treatment of pretreated and advanced Hodgkin disease]. 219 77

In the period from 1961 to 1982, 82 patients (36 females and 46 males) with Hodgkin's disease were treated. The median age was 40 years. According to the way of treatment, the patients were divided into two groups, the first group with 30 patients treated by local x-rays and/or monochemotherapy (treated up to 1971) and the second group with 52 patients treated by aggressive tele-cobalt therapy and/or MOPP polychemotherapy (after 1972). In the first group of patients, complete remission was achieved in 9 cases, partial remission in 15, while there was no remission in 6 cases. In the second group, complete remission was achieved in 40 cases, partial remission in 9, while no remission could be achieved in 3 cases. The difference in the number of remissions achieved between the patients treated up to 1971 and patients treated later is statistically significant (chi 2 = 15.52 p less than 0.0001). The median age was significantly higher in the group of patients treated by aggressive therapy (65:12 months). Seven patients from the first group survived for more than 5 years, 5 being still alive. In the second groups 29 patients survived for more than 5 years, 24 of them being still alive. The difference in survival between these two groups is significant (chi 2 = 11.37; p less than 0.001). There is a significant difference in surviving between patients in different stages of the disease (chi 2 = 27.47; p less than 0.00001). Between the patients without general symptoms (A) and the patients with systemic manifestations (B) the difference in numbers of remissions is statistically significant (chi 2 = 8.44; p less than 0.005). The difference in survival between these two groups of patients is also significant (chi 2 = 16.52; p less than 0.0001).
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PMID:[Intensive radiotherapy and polychemotherapy, clinical stage and systemic manifestations of the disease as parameters important in the prognosis for Hodgkin's disease]. 233 65

Two different calcium currents were revealed in the somatic membrane of Helix pomatia neurons. In addition to the main current described in literature, depolarizing the membrane from the holding potential level (-120 divided by -100 mV) an additional calcium current was observed. It was activated at depolarizations to -80 divided by -40 mV. Contrary to the main calcium current it did not deteriorate during intracellular perfusion by solutions containing fluoride. Time-dependence of this current could be described in the framework of the Hodgkin-Huxley model with time constants for activation and inactivation equal to tau m = 6-8 ms and tau h = 300-600 ms, respectively. The amplitude of this current increased with increase of extracellular Ca2+ concentration and decreased after addition of Co2+, Ni2+, Cd2+, nifedipine and verapamil. Dissociation constants of these substances with corresponding channels determined for the maximum of current-voltage relationship were 2 (Ca2+), 3 (Co2+), 0.06 (nifedipine) and 0.2 mmol/l (verapamil). Properties of the fluoride-insensitive calcium current and data obtained for other calcium channels are compared. Its possible functional role is also discussed.
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PMID:[2 calcium currents in the somatic membrane of neurons of Helix pomatia]. 241 33

1. Ganglion cells were dissociated from the enzyme-treated rat retina, identified with specific fluorescent labels, and maintained in vitro. Electrophysiological properties of solitary retinal ganglion cells were investigated with both conventional intracellular and patch-clamp recordings. Although comparable results were obtained for most measurements some important differences were noted. 2. The input resistance of solitary retinal ganglion cells was considerably higher when measured with 'giga-seal' suction pipettes than with conventional intracellular electrodes. Under current-clamp conditions with both intracellular and patch pipettes, these central mammalian neurones maintained resting potentials of about -60 mV and displayed action potentials followed by an after-hyperpolarization in response to small depolarizations. The membrane currents during this activity, analysed under voltage clamp with patch pipettes, consisted of five components: Na+ current (INa), Ca2+ current (ICa), and currents with properties similar to the delayed outward, the transient (A-type), and the Ca2+-activated K+ currents (IK, IA and IK(Ca), respectively). 3. Ionic substitution, pharmacological agents, and voltage-clamp experiments revealed that the regenerative currents were carried by both Na+ and Ca2+. 100 nM-1 microM-tetradotoxin (TTX) reversibly blocked the fast spikes carried by the presumptive INa, which under voltage-clamp analysis had classical Hodgkin-Huxley-type activation and inactivation. 4. Single-channel recordings of the Na+ current (iNa) permitted comparison of these 'microscopic' events with the 'macroscopic' whole-cell current (INa). The inactivation time constant (tau h) fitted to the averaged single-channel recordings of iNa in outside-out patches was slower than the tau h obtained during whole-cell recordings of INa. 5. In the presence of 1-40 microM-TTX and 20 mM-TEA, slow action potentials appeared in intracellular recordings and were probably mediated by Ca2+. The potentials were abrogated by 3 mM-Co2+ or 200 microM-Cd2+; conversely, increasing the extracellular Ca2+ concentration from 2.5 to 10-25 mM or substitution of 1 mM-Ba2+ for 2.5 mM-Ca2+ enhanced their amplitude. ICa was measured directly in whole-cell recordings with patch pipettes after blocking INa with extracellular 1 microM-TTX and K+ currents with intracellular 120-mM Cs+ and 20 mM-TEA. 6. During whole-cell recordings with patch electrodes, extracellular 20 mM-TEA suppressed IK and, to a lesser extent, IA. Extracellular 5 mM-4-AP or a pre-pulse of the membrane potential to -40 mV prior to stronger depolarization completely blocked IA.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Voltage-dependent conductances of solitary ganglion cells dissociated from the rat retina. 244 69

1. Monovalent cation selectivity and divalent cation sensitivity of the tetrodotoxin (TTX)-resistant Na+ current in dissociated adult rat nodose ganglion neurones were investigated using the whole-cell patch-clamp technique. 2. The TTX-resistant Na+ current was isolated using ion substitution and pharmacological agents. Under these conditions, the current reversal potential shifted 52 mV per tenfold change in external [Na+]. 3. Inorganic and organic monovalent cation permeability ratios (Px/PNa) were determined from changes in reversal potential and the Goldman-Hodgkin-Katz equation. The Px/PNa values determined by the former method were HONH3+, 1.38; Li+, 1.00; H2NNH3+, 0.66; NH4+, 0.28; CH3NH3+, less than 0.13; K+, less than 0.13; Rb+, less than 0.12; Cs+, less than 0.10; (CH3)4N+, less than 0.10. The values determined by either method agreed within 10%. 4. The effects of Cd2+, Co2+, Mn2+ and Ni2+ on the TTX-resistant Na+ current were analysed from peak-conductance values. These ions shifted the activation of the current to more positive potentials and decreased the maximal conductance. At 3 mM concentrations, Cd2+, Ni2+, Co2+ and Mn2+ decreased the maximal conductance 64.6, 50.7, 25.0 and 20.3%, respectively. 5. The results indicate that: (a) the monovalent cation selectivity of the TTX-resistant Na+ current is similar to that of the TTX-sensitive Na+ current in other tissues; and (b) the TTX-resistant Na+ current is less sensitive to divalent cations than the Ca2+ current in these neurones. These observations suggest that the structure determining the monovalent cation permeability of the TTX-resistant Na+ current is similar to that of the TTX-sensitive Na+ current in other tissues, and that the channels carrying the TTX-resistant Na+ current are distinct from those responsible for the Ca2+ current.
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PMID:Tetrodotoxin-resistant sodium current of rat nodose neurones: monovalent cation selectivity and divalent cation block. 244 74

1. Neurones were isolated from the CA1 region of the guinea-pig hippocampus and subjected to the whole-cell mode of voltage clamping, to determine the kinetics of voltage-gated Ca2+ channel activation. 2. Isolated neurones had an abbreviated morphology, having lost most of the distal dendritic tree during the isolation procedure. The electrical compactness of the cells facilitates voltage clamp analysis. 3. Block of sodium and potassium currents revealed a persistent current activated on depolarization above -40 mV, which inactivated slowly when the intracellular medium contained EGTA. The current was blocked by Co2+ and Cd2+, augmented by increases in Ca2+ and could be carried by Ba2+, suggesting that the current is borne by Ca2+. 4. Steady-state activation of the Ca2+ current was found to be well described by the Boltzman equation raised to the second power. 5. The open channel's current-voltage (I-V) relationship rectified in the inward direction and was consistent with the constant-field equation. 6. The kinetics of Ca2+ current onset followed m2 kinetics throughout the range of its activation. Tail current kinetics were in accord with this model. A detailed Hodgkin-Huxley model was derived, defining the activation of this current. 7. The kinetics of the currents observed in this regionally and morphologically defined class of neurones were consistent with the existence of a single kinetic class of channels.
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PMID:Calcium current activation kinetics in isolated pyramidal neurones of the Ca1 region of the mature guinea-pig hippocampus. 245 32

Ca2+ inward currents evoked by membrane depolarization have been studied by the intracellular dialysis technique in the somatic membrane of isolated dorsal root ganglion neurones of new-born rats. In about 20% of the investigated cells a hump has been detected on the descending branch of the current-voltage curve, indicating the presence of two populations of Ca2+ channels differing in their potential-dependent characteristics. An initial less regular component of the Ca2+ current was activated at membrane potentials from -75 to -70 mV. Its amplitude reached 0.2-0.9 nA at 14.6 mM-extracellular Ca2+. The activation kinetics of this component could be approximated by the Hodgkin-Huxley equation using the square of the m variable. tau m varied in the range from 8 to 1 ms at potentials between -60 and -25 mV ('fast' Ca2+ current). The second component of the Ca2+ current was activated at membrane depolarizations to between -55 and -50 mV. It could be recorded in all cells investigated and reached a maximum value of 1-7 nA at the same extracellular Ca2+ concentration. This component decreased rapidly during cell dialysis with saline solutions. The decrease could be slowed down by cooling and accelerated by warming the extracellular solution. Intracellular introduction of 3',5'-cAMP together with ATP and Mg2+ not only prevented the decrease but often restored the maximal current amplitude to its initial level. The activation kinetics of this component could also be approximated by a square function, tau m being in the range 16-2.5 ms at membrane potentials between -20 and +3 mV ('slow' Ca2+ current). The fast Ca2+ current inactivated exponentially at sustained depolarizations in a potential-dependent manner, tau h varying from 76 to 35 ms at potentials between -50 and -30 mV. The inactivation of the slow Ca2+ current studied in double-pulse experiments was current-dependent and developed very slowly (time constant of several hundreds of milliseconds). It slowed down even more at low temperature or after substitution of Ba2+ for Ca2+ in the extracellular solution. Both currents could also be carried by Ba2+ and Sr2+, although the ion-selecting properties of the two types of channels showed quantitative differences. Specific blockers of Ca2+ channels (Co2+, Mn2+, Cd2+, Ni2+ or verapamil) exerted similar effects on them. The existence of metabolically dependent and metabolically independent Ca2+ channels in the neuronal membrane and their possible functional role are discussed.
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PMID:Two types of calcium channels in the somatic membrane of new-born rat dorsal root ganglion neurones. 258 15

Currents were generated by depolarizing pulses in voltage-clamped, dissociated neurons from the CA1 region of adult guinea pig hippocampus in solutions containing 1 microm tetrodotoxin. When the extracellular potassium concentration was 100 mM, the currents reversed at -8.1 +/- 1.6 mV (n = 5), close to the calculated potassium equilibrium potential of -7 mV. The currents were depressed by 30 mM tetraethylammonium in the extracellular solution but were unaffected by 4-aminopyridine at concentrations of 0.5 or 1 mM. It was concluded that the currents were depolarization-activated potassium currents. Instantaneous current-voltage curves were nonlinear but could be fitted by a Goldman-Hodgkin-Katz equation with PNa/PK = 0.04. Conductance-voltage curves could be described by a Boltzmann-type equation: the average maximum conductance was 65.2 +/- 15.7 nS (n = 9) and the potential at which gK was half-maximal was -4.8 +/- 3.9 mV (mean +/- 1 SEM, n = 10). The relationship between the null potential and the extracellular potassium concentration was nonlinear and could be fitted by a Goldman-Hodgkin-Katz equation with PNa/PK = 0.04. The rising phase of potassium currents and the decay of tail currents could be fitted with exponentials with single time constants that varied with membrane potential. Potassium currents inactivated to a steady level with a time constant of approximately 450 ms that did not vary with potential. The currents were depressed by substituting cobalt or cadmium for extracellular calcium but similar effects were not obtained by substituting magnesium for calcium.
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PMID:Potassium current activated by depolarization of dissociated neurons from adult guinea pig hippocampus. 284 59


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