Two types of chloride channels in hen colon epithelial cells identified by patch-clamp experiments

Freshly isolated epithelial cells from hen colon were investigated using the patch-clamp technique. The aim of this investigation was to characterise the cellular conducting site for Cl- secretion. In cell-attached mode two types of Cl(-)-channels were found. Both showed distinct outward rectification. The channel types differed in single channel conductances and the marked voltage dependence of the open probabilities. A low conductance Cl(-)-channel was observed with a mean conductance at negative holding potentials of g- = 9 pS, and of g+ = 34 pS at positive potentials. This channel was predominantly open at negative potentials, corresponding to cell hyperpolarization. The second channel type observed had conductances of g- = 35 pS and g+ = 77 pS, and showed increasing open probabilities with increasing holding potentials (cell depolarisation). Both channel types were blockable by the Cl(-)-channel blocker NPPB. These data in combination with previously published transepithelial transport data on hen colon indicate that these channels are the Cl- secretory sites in colon epithelium.

Instabilities in retrieval of atmospheric trace gas profiles caused by the use of atmospheric level models

When inverse radiative transfer algorithms are applied to atmospheric level models rather than to layer models, the stability of retrieval may significantly deteriorate.

Experience with AO reconstruction plates after partial mandibular resection involving its continuity

A report is presented on experience with the use of 54 plates, without primary bone grafts, after resections for malignant tumours involving the continuity of the mandible, in 52 patients. There were complications in 27 cases: postoperative infection or soft tissue dehiscence occurred 20 times, chronic soft tissue perforation once, screw loosening twice, and plate fracture four times. Adjuvant radiotherapy and/or chemotherapy had no effect on the incidence of the complications. Seventeen of the plates (a good 30%) had to be removed prematurely due to the complications. Major deformity did not always occur if relative stabilization had developed through cicatrix formation. Thirty-seven plates (barely 70%) remained: in 19 cases until the death of the patient, in 3 cases until recurrence, in 12 cases until bone grafting, and in 3 cases they were still in situ up to 65 months. In principle, reconstruction plates have proven themselves. However, application and soft tissue coverage need great care and a great deal of experience.

[Therapy-refractory fulminant meningococcal sepsis]

Two cases of the severe form of meningococcal infection are described. A 17-year-old girl and a (unrelated) 2-year-old boy suddenly developed fever and rigor. Several hours later petechiae of the skin were noted: they rapidly spread. On admission the girl was found to have a severe consumptive coagulopathy (prothrombin 24%, partial thromboplastin time 104 sec, fibrinogen 73 mg/dl, platelets 35,000/microliters). She died two-and-a-half hours after admission of treatment-resistant shock. The boy had at first only a low prothrombin value (39%), but later the other coagulation values also became abnormal. He died 16 hours after admission from the consumptive coagulopathy and profound anaemia (haemoglobin 7.4 g/dl, haematocrit 0.23). Neither patient had any clinical signs of meningitis. Isolation of Neisseria meningitidis from blood cultures confirmed the diagnosis.

The structure of bergenin

X-ray analysis of the 3,4,8,10,11-penta-acetate (3) of bergenin has confirmed the earlier structural assignments.

Cavitation potential of mechanical heart valve prostheses

Just like technical check valves, the function of mechanical heart valve prostheses may presumably also lead to cavitation effects during valve closure. Due to the waterhammer effect, cavitation may primarily occur in the mitral position leading to high mechanical loading of the valve itself and of corpuscular blood elements. Ten different types of commercial mechanical heart valves were investigated in the mitral position of a pulsatile mock loop, to detect cavitation thresholds under physiologically similar conditions by cinematographic techniques. Almost all these valve prostheses show cavitation up to a ventricular pressure gradient of 5000 mmHg/s. The threshold depends on valve type and size and is sometimes within the physiological range below 2000 mmHg/s. Visible cavitation bubbles with a diameter of up to 1.8 mm and a collapse time of less than 0.1 ms suggest that vapour cavitation may play an important role for material and blood damage in mechanical heart valve prostheses.

[Chilaiditi's colon interposition in a patient with Rett syndrome]

We report on a patient with Rett syndrome associated with Chilaiditis interposition of the colon. Episodes of severe hyperventilation with aerophagia, immobility and obstipation facilitated the occurrence of an interposition of the colon. Conservative therapeutic measures were not successful, surgical intervention was necessary to cure the symptoms.

Gallstone dissolution with methyl tert-butyl ether in 120 patients--efficacy and safety

Of 612 patients with cholesterol gallbladder stones, 120 were eligible for percutaneous transhepatic litholysis with methyl tert-butyl ether (MTBE). Puncture of the gallbladder was successful in 117/120 (97.5%). In 113/117 (96.6%) the stones dissolved. With solitary stones, treatment lasted for an average of 4 hr, with multiple stones 10 hr. Mean hospitalization was 3.6 days. In 3/117 (2.6%) patients a bile leakage developed; 33% reported mild complaints. After the end of treatment 34% had some residue in the gallbladder; two of these patients developed recurrent stones. MTBE is exhaled, is distributed in fatty tissue, and is excreted renally together with its metabolite tert-butanol. Methanol was found only in traces. Gallbladder histology of six patients showed chronic cholecystitis. Since these findings were independent of treatment time and the interval between treatment end and operation, they are most consistent with stone-related changes rather than caused by MTBE.

Role of the adhesion molecule ICAM-1 (CD54) in staphylococcal enterotoxin-mediated cytotoxicity

Staphylococcal enterotoxin A (SEA) binds to major histocompatibility complex (MHC) class II molecules on target cells and directs human cytotoxic T lymphocytes (CTL) of irrelevant nominal specificity to mediate strong cytotoxicity against target cells. In this report we describe the importance of ICAM-1 (CD54) expression on the target cell in SEA-dependent cell-mediated cytotoxicity (SDCC), utilizing murine L cells co-transfected with HLA-DR and ICAM-1. Human CTL mediated a low but significant cytotoxicity against HLA-DR2- and HLA-DR7-transfected cells after preincubation with SEA, but no reactivity towards uncoated HLA-DR2 and HLA-DR7 cells or SEA-coated ICAM-1-transfected and untransfected L cells. In contrast, a strong cytotoxic response was mediated by CTL against L cells co-transfected with HLA-DR2/ICAM-1 and HLA-DR7/ICAM-1. Similar cytotoxic activity of the CTL was seen at a 30-fold lower effector-to-target cell ratio when comparing the HLA-DR2/ICAM-1-expressing cells with the HLA-DR2-expressing cells. SEA dose-response analysis demonstrated that the HLA-DR2/ICAM-1-expressing target cells enabled the CTL to respond to a 1000-fold lower concentration of SEA in comparison to the HLA-DR2-expressing cells. CD3+CD4+ and CD3+CD8+ cytotoxic T cell lines were equally dependent on the expression of ICAM-1 on the target cell. The strong CTL activity against HLA-DR2/ICAM-1-transfected cells could be blocked by anti-CD11a or anti-CD18 monoclonal antibodies (mAb), but not by anti-CD11b, anti-CD11c, anti-CD2 or unrelated control mAb. The great sensitivity of HLA-DR2/ICAM-1 expressing target cells to SDCC was strongly reduced by preincubation with various anti-ICAM-1 mAb but not by mAb against monomorphic HLA-DR or murine MHC class I determinants. The result in this study clearly demonstrates that efficient re-targeting of human CTL by SE is dependent on a proper interaction with the heterodimer CD11a/CD18 (Leu-CAMa, LFA-1) on the CTL and its target cell ligand ICAM-1.

Independent regulation of IFN-gamma and tumor necrosis factor by IL-1 in human T helper cells

The lymphokines IL-2 and IL-4 promoted the growth of human PHA-triggered T cells, but only IL-2 induced the production of IFN-gamma and TNF. The addition of purified monocytes strongly enhanced the production of IFN-gamma in IL-2-stimulated T cell cultures but did not influence the production of TNF or the level of T cell proliferation. The addition of IL-1 to T cells activated by PHA and optimal concentrations of IL-2 resulted in a strong induction of IFN-gamma production but had no influence on TNF production or T cell proliferation. IL-6 did not influence IFN-gamma or TNF production or T cell proliferation induced by PHA-IL-2 and did not modulate IL-1-induced IFN-gamma production. The production of IFN-gamma by CD4+ 45R+ Th cells was strongly enhanced by IL-1, whereas CD8+ T cells were less responsive to IL-1 and CD4+ 45R+ T cells were unresponsive to IL-1. We demonstrate, at the clonal level, that the optimal production of IFN-gamma by human Th cells requires both IL-1 and IL-2, whereas the production of TNF and T cell proliferation are induced by IL-2 alone. We suggest that IL-1 acts as a second signal for IFN-gamma production and that it may have an important function in regulating the pattern of lymphokines produced by T cell subsets during activation.

Independent regulation of IFN-gamma and tumor necrosis factor by IL-1 in human T helper cells

The lymphokines IL-2 and IL-4 promoted the growth of human PHA-triggered T cells, but only IL-2 induced the production of IFN-gamma and TNF. The addition of purified monocytes strongly enhanced the production of IFN-gamma in IL-2-stimulated T cell cultures but did not influence the production of TNF or the level of T cell proliferation. The addition of IL-1 to T cells activated by PHA and optimal concentrations of IL-2 resulted in a strong induction of IFN-gamma production but had no influence on TNF production or T cell proliferation. IL-6 did not influence IFN-gamma or TNF production or T cell proliferation induced by PHA-IL-2 and did not modulate IL-1-induced IFN-gamma production. The production of IFN-gamma by CD4+ 45R+ Th cells was strongly enhanced by IL-1, whereas CD8+ T cells were less responsive to IL-1 and CD4+ 45R+ T cells were unresponsive to IL-1. We demonstrate, at the clonal level, that the optimal production of IFN-gamma by human Th cells requires both IL-1 and IL-2, whereas the production of TNF and T cell proliferation are induced by IL-2 alone. We suggest that IL-1 acts as a second signal for IFN-gamma production and that it may have an important function in regulating the pattern of lymphokines produced by T cell subsets during activation.

[Idiopathic hypereosinophilia syndrome]

The author describes a case of rare idiopathic hypereosinophilia demonstrated by a 26 years old man. General symptoms were founded 4 years before and now disease takes a progressive course including a rapid decrease of visual functions. Several alterations of organic findings were also found in heart, liver, lung, spleen and brain. A marked musculatur dystrophia in regions of upper arms and calf muscles was demonstrated by the young man. Using ophthalmoscope infarctions, edema and hemorrhage in the retina were found, also new growth of vessels, hemorrhage into the vitreous body and detachment of retina.

Dysregulation of lipid metabolism in Tangier monocyte-derived macrophages

The cellular defect in Tangier mononuclear phagocytes (MNP) was shown to be associated with significant abnormalities in cellular phospholipid, triglyceride, and cholesteryl ester metabolism by using various radiolabeled precursors (32Pi, 3H-serine, 3H-choline, 14C-acetate, and 14C-oleic acid). Tangier MNP expressed increased rates of synthesis for phospholipids (twofold), triglycerides (fivefold), and cholesteryl esters (threefold) as compared to normal MNP when incubated in McCoy's medium containing 0.2% human serum albumin. The turnover rate of cellular phospholipids was also enhanced, while the turnover rates for triglycerides and cholesteryl esters were normal, thus leading to the accumulation of a larger pool of labeled triglycerides and cholesteryl esters in Tangier MNP. The individual phospholipid classes, phosphatidylcholine, sphingomyelin, phosphatidylethanolamine, and phosphatidylserine were similarly affected. Cholesterol loading led to approximately 30% down-regulation of phospholipid synthesis in normal cells, but Tangier MNP showed a smaller response. When nonloaded normal MNP were exposed to high density lipoprotein3 (HDL3), they diminished cellular cholesterol esterification mediated by acyl-CoA:cholesterol acyltransferase (ACAT); in Tangier MNP, ACAT activity increased in the presence of HDL3. When cholesterol-loaded normal and Tangier MNP were treated with HDL3, an up-regulation of phospholipid synthesis was observed in both cell types, but Tangier MNP showed a smaller response. We conclude that the defect in Tangier disease, which we recently described as a "disorder of intracellular traffic" (Schmitz et al. Proc Natl Acad Sci USA 1985;82:6305-6309), is associated with a dysregulation of cellular lipid metabolism, leading to an overproduction of triglycerides and esterified cholesterol and to enhanced synthesis and catabolism of phospholipids.

Aldosterone regulation of basolateral potassium channels in alveolar epithelium

To reveal the regulatory mechanism of the mineralocorticoid aldosterone on basolateral K+ channels, the aldosterone-sensitive lung epithelium of Xenopus laevis was investigated in Ussing chambers under voltage-clamp conditions. Transepithelial measurements were supplemented by current fluctuation analysis of short-circuit current noise in nonstimulated and aldosterone-stimulated lung tissues. The addition of 10(-6) M aldosterone stimulated short-circuit current from 11.3 +/- 2.0 to 27.8 +/- 4.8 microA/cm2 (n = 11) within 4-5 h. In the presence of an alveolar-to-pleural K+ gradient, transepithelial K+ currents were induced by permeabilizing the apical membrane with the pore-forming antibiotic amphotericin B. When the local anesthetic lidocaine (25-1,000 microM) was added to the pleural solution, macroscopic K+ current was dose dependently depressed. Lidocaine induced a Lorentzian component in the power density spectra, and the corner frequency increased linearly with blocker concentration. Aldosterone treatment did not affect mean single K+ channel current, which was 1.5 +/- 0.12 pA corresponding to a 15-pS channel conductance, whereas the number of basolateral K+ channels doubled. We conclude that the basolateral K+ channels in alveolar epithelia are a target site of aldosterone action.

Regulation of phospholipid biosynthesis during cholesterol influx and high density lipoprotein-mediated cholesterol efflux in macrophages

We have studied the rate of phospholipid synthesis and turnover in mouse peritoneal macrophages in reaction to cholesterol influx and high density lipoprotein (HDL)-mediated cholesterol efflux, using three different radioactive precursors, 32PO4(3-), [3H]choline, and [14C]oleic acid. The cells were loaded with cholesterol for up to 18 h with acetyl-low density lipoprotein (LDL), and phospholipid synthesis was measured at various time intervals and compared with nonloaded macrophages. In the first 2 h of cholesterol loading, a twofold increase in the rate of synthesis for sphingomyelin, phosphatidylcholine, phosphatidylserine-inositol, and phosphatidylethanolamine was observed. After this initial up-regulation, the rate of phospholipid synthesis continuously declined upon further cholesterol loading, while the turnover rate of cellular phospholipids was not affected under the same conditions. The lysosomal inhibitor chloroquine abolished the down-regulation, revealing a strong correlation between phospholipid synthesis and lysosomal enzyme activity which was presumably dependent on the release of cholesterol from the lysosome. The reduction in phospholipid synthesis induced by cholesterol loading is reversible by the addition of HDL3 to the cells. When HDL3 was added to the culture medium, a two- to threefold increase in phosphatidylcholine synthesis and a twofold increase in sphingomyelin formation was observed after 3 h. Ca2+ antagonists of the dihydropyridine type, which down-regulate HDL-receptor activity and promote the formation and cellular release of lamellar bodies derived from the lysosomal compartment (Schmitz, G., et al. 1988. Arteriosclerosis. 8: 46-56, and Robenek, H., and G. Schmitz. 1988. Arteriosclerosis. 8: 57-67), specifically enhance the synthesis of sphingomyelin in cholesterol-loaded macrophages. Inhibitors of acyl-CoA:cholesterol acyltransferase (Octimibate, progesterone) increase both the synthesis of sphingomyelin and phosphatidylcholine, and enhance HDL-receptor activity. The results indicate that cholesterol and phospholipid metabolism are coordinately regulated in macrophages. Moreover, the formation of phosphatidylcholine and sphingomyelin seems to be an important factor for the promotion of HDL-receptor-mediated cellular cholesterol efflux.

Radiotherapy with and without cisplatin in bladder cancer

From October 1985 to December 1988, 67 patients with invasive bladder carcinoma T1-4 N0-2 M0 were treated with irradiation (50.4 Gy in 28 fractions in 6 weeks) and simultaneous cisplatin (25 mg/m2 per day on 5 consecutive days in the first and fifth irradiation week). After transurethral resection and irradiation plus cisplatin, complete remissions were achieved in 8/11 T1-, 14/16 T2-, 27/36 T3- and 1/4 T4-tumors. The complete remission rate 6 weeks after treatment according to the extent of preceeding transurethral surgery (TUR) was: R0: 67% (8/12); R1: 83% (20/24); R2: 70% (21/30); Rx: 1/1. In patients with incomplete TUR (R1-2), the complete remission rate was 76% (41/54). This was superior to the results of a historical control (76% vs. 45%, p less than 0.01). The estimated 3-year survival according to T-stage was: T1: 73%, T2-3: 68%, T4: 25%. The overall 3-year survival was unchanged as compared to our historical control (66% each). Severe complications have not been observed. We conclude that cisplatin will likely increase the local control rate after incomplete transurethral surgery. An improvement of survival seems unlikely.

Phenotypical and functional differentiation of CD4+ CD45RA+ human T cells following polyclonal activation

Human CD4+ T cells differ in their expression of the leucocyte common antigen. Antibodies detecting certain forms (CD45RA and CD45RO) of this antigen have been used to identify and isolate subpopulations of the CD4+ T cells. These isolated subsets have been shown to have different abilities concerning lymphokine production and provision of help to B cells for Ig production. When these T-cell subsets were activated in vitro with polyclonal activators, the production. When these T-cell subsets were activated in vitro with polyclonal activators, the CD45RA+ cells lost this marker and gained the expression of CD45RO. This was true for all mitogens used in this report, i.e. accessory cell-dependent stimulation with SEA and accessory cell-independent activation with PMA or PHA. A correlation between proliferation and differentiation was observed, but this was probably not causative as stimulation with PMA in the absence of DNA synthesis resulted in the acquisition of CD45RO and loss of the CD45RA antigen. Moreover, cells proliferating vigorously for long periods of time expressed both markers at significant levels, which suggests that proliferation did not automatically result in complete loss of the CD45RA marker. The phenotypical differentiation was associated with a functional differentiation which induced the stimulated cells' ability to act as helper cells for Ig production and to produce gamma interferon (IFN-gamma). The results obtained in this study support the contention that the CD45RA+ cells are precursors of the CD45RO+ cells and that the two subsets represent different maturational stages of the same lineage.

Characterization of human glioblastoma cell lines in vitro and their xenografts in nude mice by DNA fingerprinting

Human gliomas were grown as permanent tissue cultures and xenografts in nude mice. DNA fingerprint patterns from two human gliomas were established using two different hypervariable multilocus probes [( GTG]5 and 33.15). In general the cell lines investigated showed an overall stability in the DNA fingerprint pattern. However, differences in the DNA fingerprint patterns were shown to occur depending upon the above mentioned parameters.