A single fragment of a malaria merozoite surface protein remains on the parasite during red cell invasion and is the target of invasion-inhibiting antibodies.

A complex of polypeptides derived from a precursor is present on the surface of the malaria merozoite. During erythrocyte invasion only a small fragment from this complex is retained on the parasite surface and carried into the newly infected red cell. Antibodies to this fragment will interrupt invasion.

Functional vascular diseases: Raynaud's syndrome, acrocyanosis and erythromelalgia.

Raynauds syndrome, acrocyanosis and erythromelalgia are functional vascular diseases that differ with respect to prevalence, clinical picture, therapy, prognosis, and impairment of quality of life. Raynauds syndrome occurs in 5 to 20 % of the population in Europe, is observed four times more often in women than in men and appears first at the age of 40 (3 to 80), on the average. Raynauds attacks are characterized by a paroxysmal white-blue-red or just white and blue discoloration of the fingers and toes; the attacks are induced by cold or stress, usually, cease after no more than some minutes (average 23 min.), but can also persist for hours. A distinction must be made between primary (aetiology unknown), secondary (aetiology known) and suspected secondary Raynauds syndromes (causal underlying disease suspected). There are several different therapy options, but not all of them have been substantiated by evidence. Acrocyanosis is rarer than Raynauds syndrome, and contrary to the latter, is characterized by nonparoxysmal, in most cases persistent, painless bluish-red symmetrical discolorations of the hands, feet and knees. It is more frequent in women than in men and becomes manifest before the 25th year of age, on the average (15th to 70th year of age). A distinction is made between primary acrocyanosis without detectable underlying disease and secondary acrocyanosis with a specific underlying disease. No effective therapy for primary acrocyanosis is known, but secondary forms can sometimes be treated. Patients with primary and secondary erythromelalgia, a very rare condition, sustain paroxysmal burning pain with marked reddening of the legs, feet and less often the hands. The attacks are triggered by warmth. Women are affected more often than men. The age of first manifestation is 40 to 55 years, but the first attacks may just as well occur during childhood. There are different therapeutic approaches with occasional success, but no general recommendations.

Deoxyribonucleic acid-envelope complexes from Escherichia coli. A complex-specific protein and its possible function for the stability of the complex.

The different Escherichia coli envelope fractions (cell wall, cytoplasmic membrane, and DNA-envelope complex fragments) were isolated by free-flow electrophoresis and analyzed by sodium dodecylsulfate-acrylamide gel electrophoresis. The DNA-envelope complex fragments possess a specific protein (mol wt 80,000-90,000). Upon treatment with trypsin, this protein disappears and the complex breaks down, thus releasing DNA, cell wall, and cytoplasmic membrane. Disaggregation of the complex can also be achieved by high salt concentrations. Lysozyme treatment dissolves the murein layer within the complex but does not disaggregate the complex. From these and other results on the stability of the DNA-envelope complex, conclusions can be drawn about the possible linkage within the described envelope particles.

The surface charge of rat liver mitochondria and their membranes. Clarification of some controversies concerning mitochondrial structure.

The surface charge of intact mitochondria and submitochondrial particles was examined by the technique of preparative free flow electrophoresis. When submitochondrial preparations obtained by a swelling-contraction procedure were examined with this technique, two fractions were observed. One of these fractions exhibited the same electrophoretic properties as intact mitochondria, which indicated that it was derived from the outer limiting membrane of the mitochondrion. This fraction was found to contain the enzymes monoamine oxidase and rotenone-insensitive NADH-cytochrome c reductase which have been reported to be localized in the outer mitochondrial membrane. The other fraction exhibited an electrophoretic mobility which was different from that of intact mitochondria, and this fraction contained enzymes characteristic of the inner membrane-matrix fraction such as soluble and particulate enzymes of the Krebs cycle. Microsomes exhibited an electrophoretic mobility which was almost identical with that of the outer mitochondrial membrane. In addition to resolving the localization of enzymes in mitochondrial membranes, these data indicate that the outer limiting membrane of the mitochondrion is the sole determinant of the surface charge of mitochondria.

Homogeneous cell populations from rabbit kidney cortex. Proximal, distal tubule, and renin-active cell isolated by free-flow electrophoresis.

A single-cell suspension has been prepared from rabbit kidney cortex by using a Ca-binding medium and gentle mechanical forces. The suspension was subjected to carrier-free electrophoresis, and several cell fractions were obtained. Proximal and distal tubule cell populations could be identified by their morphology. Renin-containing cells were located by means of radioimmunoassay. The morphology of the cells and their vitality (uridine incorporation) are discussed.

Cortical cell populations from rabbit kidney isolated by free-flow electrophoresis: characterization by measurement of hormone-sensitive adenylate cyclase.

Free-flow electrophoresis allows the separation of different cell populations from a cell suspension isolated from rabbit kidney cortex after perfusion of the kidneys with a calcium-binder, followed by gentle mechanical treatment. After electrophoretic separation, analysis of the adenylate cyclase activities after stimulation by various hormones allows the precise determination of the origin of the cell populations with different electrophoretic mobilities. Adenylate cyclase from the slow-moving main cell population was only sensitive to parathyroid hormone. These cells had also high alkaline phosphatase content, further demonstrating their proximal origin. The various fast-moving cell populations had adenylate cyclase sensitive to isoproterenol and arginine vasopressin but were less sensitive to parathyroid hormone than the slow-moving cells. Their alkaline phosphatase content was also much lower. This indicates that these fast-moving cell populations originate from both the granulous segment of the distal tubule and from the collecting ducts. The adenylate cyclase activity and the cyclic AMP contents of isolated proximal cells maintained in culture medium were also investigated.

The polarity of the proximal tubule cell in rat kidney. Different surface charges for the brush-border microvilli and plasma membranes from the basal infoldings.

Two different membrane fractions were obtained from a brush-border fraction of rat kidney cortex by using their different electrical surface charges in preparative free-flow electrophoresis. One membrane fraction contained only morphologically intact microvilli and was characterized by a high specific activity of alkaline phosphatase. The other fraction morphologically resembled classical plasma membranes by possessing junctional complexes and a high Na-K-ATPase activity The contamination of the isolated membrane fractions by other cell organelles was extremely low These two fractions represent the apical (luminal) and the basal (interstitial) area of the renal proximal tubule cell membrane and clearly demonstrate the polarity of this cell.

[15 years Amputierten-Initiative e.V]. / 15 Jahre Amputierten-Initiative e.V.

The Amputierten-Initiative e.V. [Amputees' initiative] was founded in Berlin as a self-help group of amputee patients in 1991. Since then, its aim has been to prevent amputations by education, to give patients sociomedical advice before and after inevitable amputations and to refer them to problem-oriented angiologists, vascular surgeons, pain therapists, orthopaedists, orthopaedic technologists, and rehabilitation centres. Because of this activity, the Amputierten-Initiative has become a member of many scientific societies, taken part in research projects and received personal and institutional honours. The acceptance and necessity of the Amputierten-Initiative and the need for its work become manifest in the rising number of its members.

Asymptomatic venous thrombosis in cancer patients--a problem often overlooked. Results of a retrospective and prospective study.

BACKGROUND: Venous thrombosis with and without pulmonary embolism is a frequent complication of malignancies and second among the causes of death in tumour patients. Its incidence is reported to be 10 to 15%. Since for methodological reasons, this rate can be assumed to be too low and to disregard asymptomatic venous thrombosis, a combined retrospective and prospective study was performed to examine the actual frequency of venous thrombosis in tumour patients. PATIENTS AND METHODS: The histories of 409 patients (175 women, 234 men, mean age 69 years [19 to 96 years]) with different tumours, consecutively enrolled in the order of their altogether 426 inpatient treatments, were checked in retrospect for the frequency of venous thrombosis and pulmonary embolism. Subsequently, 97 tumour inpatients (36 women, 61 men, mean age 70 years [42 to 90 years]) were systematically screened, by means of duplex sonography and/or venography, for venous thromboses in the veins of the pelvis and both legs. RESULTS: In the retrospective analysis, where no systematic screening for thromboses was performed and only symptomatic thrombosis was recorded, venous thrombosis was found in 6.6% of all tumour patients, whereas in the prospective examination with systematic duplex sonography and / or venography of all patients, the percentage was 33%. In the prospective study, 31.3% of venous thromboses were symptomatic and 68.7% asymptomatic. In 39.3% of the cases in the retrospective analysis and 25% in the prospective analysis, venous thrombosis occurred during chemotherapy, surgery or radiation therapy. Venous thrombosis was most often seen in metastasizing tumours and in colorectal carcinoma (40%), haematological system diseases (28.6%), gastric cancer (30%), bronchial, pancreas and ovarian carcinoma (28.6%), and carcinoma of the prostate (16.7%). CONCLUSION: Regular screening for thrombosis is indicated even in asymptomatic tumour patients because asymptomatic venous thrombosis is frequent, can lead to pulmonary embolism and has to be treated like symptomatic venous thrombosis. This is particularly true for metastasization during chemotherapy, surgical interventions, or radiation.

Circulating nerve growth factor in primary and secondary Raynaud's syndrome - results of a pilot study.

BACKGROUND: In this pilot study we examined circulating concentrations of nerve growth factor (NGF) in controls and patients suffering from primary or secondary Raynaud's syndrome and determined their relation to digital vasospasm. PATIENTS AND METHODS: Eighteen controls, 16 patients with primary RP and 19 patients with systemic sclerosis (SScl) were included. Degree of vasospasm was graduated according to the degree of plethysmographically measured vasospastic reaction after cold test. A diary was handed out for documentation of the daily number and duration of RP during a period of 16 days. Circulating NGF levels were analysed by a commercial ELISA (Promega Inc., USA). RESULTS: SScl-patients were significantly older (p < 0.0001) and more severely affected by spontaneously occurring RP (p = 0.03), whereas the severity of the vasospastic reactions after a standard cold test were not significantly different between the groups (p = 0.09). Within each study group and between the study groups elevated NGF levels were observed only in SScl-patients after thermal provocations (p = < 0.05). In a correlation analysis restricted to patients with PRP or SRP, the degree of vasospasm after cold testing as well as the intensity of Raynaud's symptoms were not correlated with NGF-levels (p = n.s.). CONCLUSIONS: Our results do not support the hypothesis that NGF plays a major role in the generation of vasospasm in Raynaud's phenomenon.

Concomitant neurological and orthopaedic diseases in the presence of peripheral arterial disease: a prospective study.

BACKGROUND: The symptoms of peripheral arterial disease (PAD) can be masked by neurological or orthopaedic diseases with identical symptoms, which may result in faulty therapy decisions, if the diagnosis is solely based on the reported complaints and angiographic or duplex ultrasonographic findings. A prospective study was therefore performed to find out how often established PAD is accompanied by neurological or orthopaedic pictures that can blend into the PAD symptoms. PATIENTS AND METHODS: The examination was performed in 235 patients with PAD of Fontaine's stages II to IV, 125 were women and 110 men; the mean age was 71 years (41 to 95 years). They were systematically examined for angiologic, neurological and orthopaedic diseases. RESULTS: 44% of the patients enrolled in the study suffered from a neurological disease, 45% from an orthopaedic disease and 24.7% from both a neurological and an orthopaedic disease. The frequency of concomitant diseases depended on the stage of PAD. In Fontaine's stage II, alterations due to arthrosis or arthritis were found in 12% of the patients, peripheral neuropathies in 14%, radiculoneuropathies in 16% and malpositions of the foot in 16%. In Fontaine's stage III, arthrosis and arthritis were predominant at a percentage of 38.5%; peripheral neuropathies were diagnosed in 15.4% of the patients. Patients with Fontaine's stage IV most often showed peripheral polyneuropathies at 42.1% and malpositions of the foot at 28.4%. CONCLUSIONS: Because of the frequency of neurological and orthopaedic pictures with identical symptoms, a differential diagnosis before the initiation of a PAD therapy is imperative.

[Vasoactive agents and prostanoids in the therapy of PAD: facts, questions, disproven assumptions]. / Vasoaktive Substanzen und Prostanoide in der Therapie der pAVK. Was ist gesichert, was offen, was überholt?

In the view of the AkdA (Drug Committee of the German Medical Profession), the efficacy in intermittent claudication is currently proven only for Naftidrofuryl, whereas in the opinion of the DGA (German Society of Angiology) also that of prostaglandin E(1) is proven. Both drugs are indicated if neither walking exercise nor vascular or endovascular reconstruction are feasible. In critical limb ischaemia (Fontaine stage III/IV), the efficacy of prostaglandin E(1) and iloprost is proven according to both the treatment recommendations of the DGA and the ACC/AHA Guidelines. The AkdA also agrees with the administration of prostanoids, even though it considers their efficacy not sufficiently proven in accordance with CPMP criteria. Here, prostaglandin E(1) is approved for the treatment of Fontaine's stage III/IV regardless of its etiology, whereas iloprost is approved only for the treatment of thrombo-angiitis obliterans.

Beef-heart submitochondrial particles: a mixture of mitochondrial inner and outer membranes.

1. EPR spectra at 9 GHz and 83 degrees K of NADH-reduced anaerobic beef-heart submitochondrial particles, prepared from mitochondria by sonication and centrifugation, contain a signal (gz equals to 2.01, gy equals to 1.94, gx equals to 1.89) due to an iron-sulphur center of the mitochondrial outer membrane. 2. The ratio of inner and outer membranes in submitochondrial particles is not greatly different from that in beef-heart mitochondria. 3. Beef-heart submitochondrial particles free from outer-membrane contamination have been prepared by free-flow electrophoresis. EPR spectra at 83 degrees K of such particles are presented.

Fractionation of membrane vesicles. II. A method for separation of membrane vesicles bearing different enzymes by free-flow electrophoresis.

Free-flow electrophoresis was used to subfractionate membrane vesicles from calf thymocyte plasma membranes. The fractionation resulted in a separation of vesicle populations bearing four different enzymes: alkaline nitrophenyl-phosphatase (orthophosphoric-monoester phosphohydrolase (alkalin optimum) EC 3.1.3.1), gamma-glutamyltransferase (EC 2.3.2.2), (Mg2+ + Na+ + K+)-ATPase (ATP phosphohydrolase, EC 3.6.1.3) and acyl-CoA:lysophosphatidylcholine acyltransferase (acyl-CoA:1-acylglycero-3-phosphocholine-O-acyltransferase, EC 2.3.1.23). The specific content of cholesterol and total phospholipid coincided with the distribution of membrane-bound protein. However, vesicles migrating towards the cathode had a higher molar ratio of cholesterol to phospholipid (0.75) compared to those migrating to the anode (0.55). Sodium dodecyl sulphate-gel electrophoresis of pooled vesicle fractions also demonstrates distinct differences in their protein pattern. Electron-micrographic thin sections show that the vesicle populations have a similar morphology and size distribution. These results are discussed in terms of heterogeneity of the original thymocytes, contamination with intracellular membranes and a heterogeneous structure of the plasma membrane.

Prostaglandin E1 infusion therapy in dry age-related macular degeneration.

OBJECTIVE: The pilot study is intended to show whether prostaglandin E1 (PGE1) infusions are able to stop the gradual vision loss in dry age-related macular degeneration (AMD) and, further, to stabilize or improve visual acuity. METHODS: With PGE1 infusions 11 patients with different forms of dry AMD were treated and compared with a control group of 10 untreated patients with dry AMD. The target parameter was the visual acuity, as determined with the ETDRS logMAR charts. Other examinations performed during the study were tests of contrast vision, colour vision and central visual fields, as well as autofluorescence and fluorescein angiography and multifocal electroretinography. RESULTS: On termination of the infusions, six patients showed an increase in visual acuity by at least one line, an improvement that was seen in eight patients 2 months after the end of the infusion therapy. After 6 months, one patient exhibited an improvement of visual acuity by three lines and three patients an improvement by one line. Five patients were found to show no change of their baseline acuity values after 6 months, while two patients exhibited an impairment by one line. The visual acuity in the dry AMD control group without PGE1 treatment had decreased by 0.8 lines on the average after 6 months. Contrast vision, central visual fields and the multifocal electroretinogram showed improvements on the termination of infusions and up to 2 months later; no substantial change of these parameters, as compared with the baseline findings, was seen 6 months after the termination of infusions. SUMMARY: This pilot study suggests that PGE1 infusions have a stabilizing or improving effect on the visual acuity of patients with dry AMD. Owing to the limitations of a pilot study, these results should, however, be validated in a larger, randomized and blinded study.

Are there predictors for the outcome of a PGE1 treatment in peripheral arterial disease with critical limb ischaemia?

BACKGROUND: In a multivariate retrospective analysis was conducted to examine whether and to what extent PGE1 is therapeutically effective and whether there are predictors of response. PATIENTS AND METHODS: The examination included 767 patients (448 women, 319 men) of a mean age of 71.2 years and with peripheral arterial disease (PAD) having existed for 44.7 months on the average. They suffered from critical limb ischaemia (Fontaine's stages III/IV) and showed average tcpO2 values at the instep of 2 mmHg (0 to 15) and average systolic malleolar artery pressures of 18 mmHg (0 to 35 mmHg). Between 1989 and 2001, the patients had received treatments in hospital with i.v. PGE1 doses (2x20 microg or 1x60 microg/day) for an average of 34.2 days (mean of responder- and non-responder group). Patients were called responders when pain had markedly decreased or disappeared, necroses had been reduced or healed completely, and vascular reconstruction, PTA or amputations were not necessary. RESULTS: The clinical analysis showed 82.4% of the patients to be responders and 17.6% to be non-responders. It was demonstrated that the outcome of the therapy was not dependent on the supine or sitting tcpO2, the malleolar artery pressure, the patient's age or sex, the duration of PAD, the number or kind of concomitant diseases, the patient's general condition, the localization and number of vascular occlusions, the kind of prior therapy, or the number of previous amputations, although differences in some of the parameters, while clinically irrelevant, were found to be statistically significant. They are not predictors of the outcome of a PGE, therapy. CONCLUSIONS: Even in extremely bad haemodynamic situations at the beginning of a therapy (malleolar artery pressures from 0 to 35 mmHg, tcpO2 0 to 15 mmHg, multilevel occlusive disease, multiple previous operations and concomitant diseases), PGE, therapies of more than 20 days - on the average 35.6 days (mean of responder group) - duration allow clinically relevant positive results to be achieved.

Subfractionation of rat liver Golgi apparatus by free-flow electrophoresis.

Using the technique of preparative free-flow electrophoresis, cisternae of unstacked rat liver Golgi apparatus were separated into a series of fractions of increasing content of sialic acid, thiamine pyrophosphatase and 5'-nucleotidase, markers regarded as being concentrated toward the mature Golgi apparatus face. These same fractions showed a decreasing content of nucleoside diphosphatase, an endoplasmic reticulum marker. Fractions enriched in sialic acid also were enriched in cisternae from the mature or trans face of the Golgi apparatus as deduced from cytochemical criteria. Those fractions least enriched in sialic acid contained cisternae that accumulated deposits of reduced osmium under standard conditions, a test used to mark the opposite, forming or cis-face. Thus subfractionation along the functional polarity axis of the Golgi apparatus with separation of cis and trans face cisternae has been achieved.

Fragments of the polymorphic Mr 185,000 glycoprotein from the surface of isolated Plasmodium falciparum merozoites form an antigenic complex.

Merozoites of the human malaria parasite Plasmodium falciparum express on their surface several antigens derived from a polymorphic glycoprotein precursor of Mr 185,000 synthesised earlier on by trophozoites and schizonts. A panel of 18 monoclonal antibodies against a range of different specificities of the precursor was used to characterise its mature products in spontaneously released merozoites. Merozoites released by [35S]methionine or [14C]glucosamine-labelled schizonts, or surface 125I-labelled purified merozoites, were extracted in detergents, and the antigens were detected by immunoprecipitation or Western blotting. We show that a nonglycosylated peptide of Mr 80,000 and two glycosylated fragments of Mr 40,000 and Mr 16,000, all derived from the precursor, are exposed on the surface of the mature merozoite. Precipitations from extracts in different detergents indicate that the 80 and 40 kDa fragments can form a non-covalent complex with each other and two additional major surface antigens of 36 and 22 kDa. Several antibodies react strongly with the complex but not with its dissociated subunits, thus indicating presence of conformational epitopes. Other epitopes are positively mapped on different dissociated subunits by immunoprecipitation and Western blotting. The 80 and 40 kDa antigens each carry a different polymorphic marker epitope, and both of these markers are absent on the 16 kDa fragment. The 40 and 16 kDa glycoproteins share common epitopes, and the latter may be derived from the former fragments. Only epitopes present on the 16 kDa antigen, but not those specific for the larger fragments, are detectable by immunofluorescence in the ring-stage. This indicates that the whole or a part of the 16 kDa antigen remains on the parasite through the invasion process.

Time-course of synthesis, transport and incorporation of a protein identified in purified membranes of host erythrocytes infected with a knob-forming strain of Plasmodium falciparum.

Membranes from host erythrocytes infected with a knob-positive strain of Plasmodium falciparum were purified by free-flow electrophoresis or gradient centrifugation. In these membranes the main parasite-derived protein was a 92000 Da protein which was not present after infection of erythrocytes with the corresponding knob-negative strain. The protein is synthesized between 9-21 h after merozoite invasion and then synthesis ceases. At least 6 h elapses between the start of synthesis and the appearance of the protein in the erythrocyte membrane. No precursor proteins for the 92000 Da protein were found. Since the purified erythrocyte membranes were free from contamination with whole parasites or parasite membranes, the 92000 Da protein is clearly present in the host erythrocyte membrane.

The N-terminal amino acid sequences of the Plasmodium falciparum (FCB1) merozoite surface antigens of 42 and 36 kilodalton, both derived from the 185-195-kilodalton precursor.

The N-terminal amino acid sequences of the 42- and 36-kDa Plasmodium falciparum (strain FCB1) merozoite surface polypeptides, both processing fragments from the 185-195-kDa polymorphic glycoprotein, have been obtained. The N-terminus of the 42-kDa fragment is located in the amino acid sequence of the precursor molecule at amino acid residue 1255 (numbering according to Mackay, M., Goman, M., Bone, N., Hyde, J.E., Scaife, J., Certa, U., Stunnenberg, H. and Bujard, H. (1985) EMBO J. 4, 3823-3829). The peptide bond cleaved during processing is Glu-Ala. This fragment is derived from the C-terminal end of the precursor molecule. The N-terminus of the 36-kDa fragment is located in the precursor molecule at amino acid residue 902 (numbering as above), and the bond cleaved is Asn-Asp.