Vitamin D and axonal injury in multiple sclerosis

Background:

Previous studies in patients with multiple sclerosis (MS) have shown an association between high serum 25-hydroxyvitamin D (25[OH]D) levels and decreased inflammatory activity.

Objective:

The purpose of this study was to examine the association between 25(OH)D levels and axonal injury in MS. Cerebrospinal fluid neurofilament light (CSF-NFL) was used as a marker for axonal injury.

Methods:

Patients were identified through clinical practice at the Department of Neurology in Umeå University Hospital, Sweden. Blood draw, magnetic resonance imaging, scoring of disability and lumbar puncture were performed at inclusion in 153 patients, and also at median 12 months follow-up in 87 patients. For analyses of serum 25(OH)D levels and CSF-NFL, enzyme-linked immunosorbent assays were used.

Results:

There was an inverse association between serum 25(OH)D and CSF-NFL levels in categorical (dichotomized at 75 or 100 nmol/l) analyses. A dose-response effect for 25(OH)D levels on CSF-NFL levels ( p for trend=0.034) was also present. Serum 25(OH)D levels above 100 nmol/l were associated with lower CSF-NFL levels independently of ongoing MS treatment.

Conclusion:

High 25(OH)D levels are associated with decreased axonal injury in MS.

The roles of RgpB and Kgp in late onset gingipain activity in the vimA-defective mutant of Porphyromonas gingivalis W83

Previous studies have shown that VimA, an acetyltransferase, can modulate gingipain biogenesis in Porphyromonas gingivalis. Inactivation of the vimA gene resulted in isogenic mutants that showed a late onset of gingipain activity that only occurred during the stationary growth phase. To further elucidate the role and contribution of the gingipains in this VimA-dependent process, isogenic mutants defective in the gingipain genes in the vimA-deficient genetic background were evaluated. In contrast with the wild-type strain, RgpB and Kgp gingipain activities were absent in exponential phase in the ∆rgpA::tetQ-vimA::ermF mutant. However, these activities increased to 31 and 53%, respectively, of that of the wild-type during stationary phase. In the ∆rgpA::cat-∆kgp::tetQ-vimA::ermF mutant, the RgpB protein was observed in the extracellular fraction but no activity was present even at the stationary growth phase. There was no gingipain activity observed in the ∆rgpB::cat-∆kgp::tetQ-vimA::ermF mutant whereas Kgp activity in ∆rgpA::cat-∆rgpB::tetQ-vimA::ermF mutant was 24% of the wild-type at late stationary phase. In contrast to RgpA, the glycosylation profile of the RgpB catalytic domain from both W83 and P. gingivalis FLL92 (vimA::ermF) showed similarity. Taken together, the results suggest multiple gingipain activation pathways in P. gingivalis. Whereas the maturation pathways for RgpA and RgpB are different, the late-onset gingipain activity in the vimA-defective mutant was due to activation/maturation of RgpB and Kgp. Moreover, unlike RgpA, which is VimA-dependent, the maturation/activation pathways for RgpB and Kgp are interdependent in the absence VimA.

Renal retransplantation in patients with HLA-antibodies

The results of 92 consecutive renal retransplantations, performed during a 5-year period in recipients with HLA-antibodies, were retrospectively analysed. The actuarial 1-year graft survival (1-y GS) was 65% for all retransplantations, as compared with 63% for first grafts in sensitized recipients. For the second (n = 56), third (n = 24) and fourth-fifth (n = 12) grafts 1-y GS was 64%, 71% and 58%, respectively. Acute rejection was the major cause of graft loss (45%). Recipients with > 3 years GS of the preceding transplant had significantly better GS at retransplantation. Also, grafts with no HLA mismatches had significantly prolonged GS. One-y GS was 78% when PRA (panel reacting antibody) was less than 50%, and 60% when PRA was more than 50%. A benefit of repeated mismatches was demonstrated in the subgroup with PRA < 50%, in contrast to recipients with PRA > 50%, suggesting that, in some patients, an absence of antibody response against certain antigens might be used as a basis for future deliberate mismatching.

Improved systems for hydrophobic tagging of recombinant immunogens for efficient iscom incorporation

We have previously reported a strategy for production in Escherichia coli of recombinant immunogens fused to a hydrophobic tag to improve their capacity to associate with an adjuvant formulation [Andersson et al., J. Immunol. Methods 222 (1999) 171]. Here, we describe a further development of the previous strategy and present significant improvements. In the novel system, the target immunogen is produced with an N-terminal affinity tag suitable for affinity purification, and a C-terminal hydrophobic tag, which should enable association through hydrophobic interactions of the immunogen with an adjuvant system, here being immunostimulating complexes (iscoms). Two different hydrophobic tags were evaluated: (i) a tag denoted M, derived from the membrane-spanning region of Staphylococcus aureus protein A (SpA), and (ii) a tag denoted MI consisting of the transmembrane region of hemagglutinin from influenza A virus. Furthermore, two alternative affinity tags were evaluated; the serum albumin-binding protein ABP, derived from streptococcal protein G, and the divalent IgG-binding ZZ-domains derived from SpA. A malaria peptide M5, derived from the central repeat region of the Plasmodium falciparum blood-stage antigen Pf155/RESA, served as model immunogen in this study. Four different fusion proteins, ABP-M5-M, ABP-M5-MI, ZZ-M5-M and ZZ-M5-MI, were thus produced, affinity purified and evaluated in iscom-incorporation experiments. All of the fusion proteins were found in the iscom fractions in analytical ultracentrifugation, indicating iscom incorporation. This was further supported by electron microscopy analysis showing that iscoms were formed. In addition, these iscom preparations were demonstrated to induce M5-specific antibody responses upon immunisation of mice, confirming the successful incorporation into iscoms. The novel system for hydrophobic tagging of immunogens, with optional affinity and hydrophobic tags, gave expression levels that were increased ten to fifty-fold, as compared to the earlier reported system. We believe that the presented strategy would be a convenient way to achieve efficient adjuvant association for recombinant immunogens.

Characterisation of STREAMLINE phenyl

STREAMLINE Phenyl is a new hydrophobic interaction chromatography support designed for use in expanded bed adsorption. The phenyl groups are linked to STREAMLINE matrix via highly stable ether linkages. Within this development project the chemical and chromatographic stability as well as the breakthrough capacity for human IgG has been studied. The chemical stability was monitored as the carbon leakage from the matrix to the storage solution, pH 1-14 at 20 and 40 degrees C. The carbon content in the supernatant was determined with Total Organic Carbon (TOC) technique. In the chromatographic stability study STREAMLINE Phenyl was stored in eight different storage solutions under ambient conditions for 12 weeks and then tested in a chromatographic function test. The results show that the adsorbent is chemically stable and that the chromatographic properties are retained under the tested conditions. The breakthrough capacity study demonstrates the importance of the bed height for obtaining maximal dynamic capacity. Further, there is a good correlation between breakthrough data generated from packed bed and expanded bed runs.

A fast and simple method to calculate protonation states in proteins

A simple model for electrostatic interactions in proteins, based on a distance and position dependent screening of the electrostatic potential, is presented. It is applied in conjunction with a Monte Carlo algorithm to calculate pK(alpha) values of ionizable groups in proteins. The purpose is to furnish a simple, fast, and sufficiently accurate model to be incorporated into molecular dynamic simulations. This will allow for dynamic protonation calculations and for coupling between changes in structure and protonation state during the simulation. The best method of calculating protonation states available today is based on solving the linearized Poisson-Boltzmann equation on a finite difference grid. However, this model consumes far too much computer time to be a practical alternative. Tests are reported for fixed structures on bacteriorhodopsin, lysozyme, myoglobin, and calbindin. The studies include comparisons with Poisson-Boltzmann calculations with dielectric constants 4 and 20 inside the protein, a model with uniform dielectric constant 80 and distance-dependent dielectric models. The accuracy is comparable to that of Poisson-Boltzmann calculations with dielectric constant 20, and it is considerably better than that with epsilon = 4. The time to calculate the protonation at one pH value is at least 100 times less than that of a Poisson-Boltzmann calculation. Proteins 1999;36:474-483.

General expression vectors for production of hydrophobically tagged immunogens for direct iscom incorporation

A new general strategy for the production of recombinant protein immunogens has been investigated. The rationale involves the production of a recombinant immunogen as fused to a composite tag comprising one domain suitable for affinity purification and a hydrophobic tag designed for direct incorporation through hydrophobic interaction of the affinity-purified immunogen into an adjuvant system, in this case immunostimulating complexes (iscoms). Three different hydrophobic tags were evaluated: (i) a tag denoted IW containing stretches of hydrophobic isoleucine (I) and tryptophan (W) residues; (ii) a tag denoted MI consisting of the transmembrane region of hemagglutinin from influenza A virus; and (iii) a tag denoted PD designed to be pH-dependent in such a way that an amphiphatic alpha-helix would be formed at low pH. As an affinity tag, an IgG-binding domain Z derived from Staphylococcus aureus protein A (SpA) was used, and a malaria peptide M5, derived from the central repeat region of the Plasmodium falciparum blood-stage antigen Pf155/RESA, served as a model immunogen in this study. Three different fusion proteins, IW-Z-M5, MI-Z-M5 and PD-Z-M5, were produced in Escherichia coli, and after affinity purification these were evaluated in iscom-incorporation experiments. Two of the fusion proteins, IW-Z-M5 and MI-Z-M5 were found in the iscom fraction following preparative ultracentrifugation, indicating iscom incorporation. This was further supported by electron microscopy analysis showing that iscoms were formed. Furthermore, these iscom preparations were demonstrated to induce efficient M5-specific antibody responses upon immunization of mice, confirming successful incorporation into iscoms. The implications of these results for the design and production of subunit vaccines are discussed.

pKa calculations along a bacteriorhodopsin molecular dynamics trajectory

Electrostatic calculations of pK(a-values) are reported along a 400 ps molecular dynamics trajectory of bacteriorhodopsin. The sensitivity of calculated pK(a) values to a number of structural factors and factors related to the modelling of the electrostatics are also studied. The results are very sensitive to the choice of internal dielectric constant of the protein (in the interval 2-4). Moreover it is important to include internal water molecules and to average over a long enough portion ( approximately 100 ps) of an equilibrium molecular dynamics trajectory. The internal waters are necessary to get an ion-counter ion complex with the Schiff base and Arg 82 protonated and the aspartic groups (85 and 212) deprotonated. The fluctuations along the MD-trajectory do not change the protonation state of internal residues at neutral pH. However, at other pH values the averaging along a trajectory maybe crucial to get correct protonation states. A relationship is found between the arginine group 82, the aspartic group 85 and the glutamate group 204. Glu 204 is protonated in the ground state but the pK(a) value decreases towards deprotonation when the chromophore isomerizes into the cis state.

[Painless femoral neck fracture in a patient with multiple sclerosis]

We describe a patient with multiple sclerosis who suffered a painless hip fracture. She was admitted to the hospital three weeks after falling on her left hip. She had been unable to walk after the trauma, but had had no pain. The condition was initially misinterpreted as multiple sclerosis schub. X-ray examination showed fracture of the left femoral neck, and by the time she was admitted to hospital the patient was paretic. She has improved substantially after an operation involving cementless total hip arthroplasty. Painless fractures in patients with multiple sclerosis may be confused with exacerbations of their neurological disease.

Increased serum levels of anti-elastin antibodies in patients with Peyronie's disease

The cause of Peyronie's disease is unknown. Immunological mechanisms in the pathogenesis have been previously suggested. Antibodies to elastin are present in all individuals. However, abnormal serum levels of anti-tropoelastin (reflecting elastin synthesis) and anti-alpha-elastin (reflecting elastin destruction) are seen in a variety of autoimmune diseases. We show that patients with Peyronie's disease have higher levels of antibodies to tropoelastin (p < 0.047) and alpha-elastin (p < 0.012) than age-matched controls, suggesting an increase in elastin synthesis and breakdown, respectively. These findings suggest the presence of autoimmune mechanisms in the pathogenesis of Peyronie's disease, which may have future diagnostic and therapeutic implications.

Abnormal immune function in malignant hypertension

OBJECTIVE

To investigate the extent to which the immune system is influenced in patients with previous malignant hypertension.

DESIGN

Twenty-three patients with malignant hypertension (fundus hypertonicus grades III or IV) in the Gothenburg area were studied over a 3-year period. After treatment had been instituted they were investigated to establish the function of the cellular immune system (number of T lymphocytes and the proliferative response to T-cell mitogens), human leucocyte antigens A, B and C and frequency of autoantibodies.

METHODS

The numbers of T lymphocytes were quantified as erythrocyte rosettes. Lymphocyte-stimulation tests were carried out using the T-cell mitogens phytohaemagglutinin and concanavalin-A. Autoantibodies were determined with immunoassay techniques and leucocyte A, B and C antigens with a lymphocytotoxicity test.

RESULTS

The frequency of T lymphocytes and their baseline thymidine incorporation were significantly depressed in patients with previously malignant hypertension compared with control subjects. The group with malignant hypertension also had a decreased proliferative response to concanavalin-A but not to phytohaemagglutinin, and they had an increased frequency of antinuclear antibodies. Human leucocyte antigen B15 tended to occur more frequently in patients with malignant and non-malignant hypertension than in control subjects, especially if a family history of hypertension was taken into consideration.

CONCLUSION

The results from the present study indicate that immune mechanisms are involved in malignant hypertension, either secondary to the vascular damage or as a primary abnormality.

"Panic disorder" in schizophrenia

A patient is described with operationally diagnosed chronic schizophrenia who simultaneously experienced repeated "attacks" during which times he had intense apprehension and autonomic hyperactivity entirely similar to that usually described under the rubric of "panic attacks" in nonschizophrenic patients. Delusional and hallucinatory symptoms were also transiently exacerbated during these episodes. Alprazolam, as an adjunct to fluphenazine decanoate, was effective in ameliorating these symptoms. Diagnostic and treatment implications are discussed.

Use of a somatostatin analog (SMS 201-995) in the glucagonoma syndrome

A long-acting somatostatin analog, SMS 201-995, is now available to treat the hormonal manifestations of islet cell tumors. We report its use in a patient with a metastatic glucagonoma refractory to conventional therapy. This patient, who was severely disabled by the rash of necrolytic migratory erythema and brittle diabetes mellitus, allowed us to evaluate the therapeutic efficacy of SMS 201-995 and to gain insight into the origin of the rash. SMS 201-995 was administered subcutaneously (.05 mg twice a day). The rash improved markedly within 48 hours and was completely resolved within 1 week of treatment. Insulin requirements decreased from 90 U/day to zero during the first week of treatment. Corresponding to improvement in clinical symptoms circulating glucagon levels showed a marked decrease. There was no substantial change in plasma or urinary levels of zinc or in plasma amino acid levels. When SMS 201-995 was stopped, the rash recurred within 36 hours and it improved within 48 hours of readministration. The rash and diabetes have remained well controlled during 8 months of therapy but no change in tumor size has been seen on CT scan. The rapid changes in the rash related to the administration of SMS 201-995 indicate that the pathogenesis of necrolytic migratory erythema is probably due to circulating hyperglucagonemia or some other hormonal substance produced by the tumor.

Myocardial depression during acute pancreatitis: fact or fiction?

Clinical and experimental evidence suggests that myocardial depression occurs during severe pancreatitis, but this evidence is derived from techniques that are not optimal for assessing myocardial contractility (e.g., rate of rise in ventricular pressure [dP/dt]). The slope of the left ventricular (LV) and systolic pressure dimension relationship (Ees), a better indicator of myocardial function, has not been measured in pancreatitis. Ten mongrel dogs underwent surgical instrumentation to monitor systemic arterial and LV pressure, cardiac output, LV dP/dt, and anterior LV wall thickness. End of systole was defined by the peak negative dP/dt. The end-systolic points used to calculate Ees were obtained by aortic and vena caval occlusion. After surgical recovery, pancreatitis was induced via cannulation of the pancreatic duct and injection of autologous bile (1 ml/kg) at 200 mm Hg perfusion pressure. All measurements were taken during a control period and daily after pancreatitis was induced. Pancreatitis was confirmed by a significant increase in serum amylase throughout the study and by autopsy finding of hemorrhagic necrosis. Ees was increased throughout the experimental protocol (1 to 7 days) (p less than 0.05). Myocardial performance as assessed by Ees was significantly increased and myocardial depression did not occur in untreated, conscious dogs with severe pancreatitis. Peak positive LV dP/dt was a poor index of contractility during pancreatitis since it decreased while myocardial contractility was increased. Cardiac depression in pancreatitis noted in other reports was likely due to decreased preload and not to intrinsic cardiac dysfunction.

Effect of heparin and heparin fractions on experimental abscess formation

To evaluate the effectiveness of heparin and heparin fractions in decreasing abscess formation, rats were divided into six groups. A fibrin clot containing 10(9) live Escherichia coli was placed in the peritoneal cavity of each rat. Group 1 (controls) received daily subcutaneous (SQ) injections of 0.1 mL of saline solution. Group 2 received daily intramuscular injections of gentamicin, 12.5 mg/kg. Group 3 received a daily SQ dose of 30 U of porcine heparin. In addition to gentamicin, group 4 received heparin, group 5 received heparin fraction PK10169, and group 6 received heparin fraction CY216, all in daily SQ doses of 30 U. Survivors were killed at ten days and examined for intra-abdominal abscesses. All group 1 animals developed abscesses. Abscess formation was significantly decreased in all groups receiving gentamicin. When used with gentamicin, neither heparin nor heparin fractions decreased the number of abscesses formed when compared with gentamicin alone. Heparin or heparin fractions in combination with gentamicin did decrease abscess size significantly when compared with controls.

Serum calcium metabolism in acute experimental pancreatitis

Serum calcium changes in severe pancreatitis were studied in 23 dogs. Twelve dogs underwent duodenotomy and served as controls. Pancreatitis was induced in the other 11 by autologous bile injection (1 ml/kg) into the pancreatic duct. Serum amylase, total calcium, ionized calcium, albumin, magnesium, chloride, phosphorous, parathyroid hormone (PTH), and calcitonin were measured at 0, 1/2, 1, 3, 6, 24, 48, and 72 hours after duodenotomy or bile injection. Serum amylase levels became significantly elevated in all dogs with pancreatitis at 30 minutes (p less than 0.01) and remained so throughout the entire experiment. Total calcium levels dropped significantly 30 minutes after pancreatitis was induced from 10.0 +/- 0.3 mg/dl compared with 8.8 +/- 0.4 mg/dl in control dogs (p less than 0.05) and remained statistically lower for as long as 1 hour. Ionized calcium levels were significantly lower than were those of control dogs at 1/2, 1, 3, and 6 hours (p less than 0.05). Serum magnesium and chloride levels showed no significant changes between both groups. The only significant difference in phosphorus values was at 6 hours when they were higher in dogs with pancreatitis than in controls (6.2 +/- 0.3 mg/dl versus 4.8 +/- 0.4 mg/dl; p less than 0.05). Serum albumin levels remained unchanged throughout the study except for 48 hours when they were significantly lower in animals with pancreatitis (p less than 0.02). PTH levels were significantly greater in dogs with pancreatitis than in controls at 1, 3, 6, and 24 hours (p less than 0.05). There was no significant difference in calcitonin levels between both groups. Ionized calcium is a more reliable indicator of calcium fluxes in acute experimental pancreatitis since it remains depressed longer than total serum calcium. The time course of PTH elevation indicates a reaction to hypocalcemia, and failure of PTH secretion is not the cause of hypocalcemia in pancreatitis. This study does not support elevation of calcitonin as a cause of hypocalcemia in acute pancreatitis.

Androgen receptors in human thyroid tissue

To evaluate the potential effect of androgens on human thyroid tumors, the incidence and distribution of cytosolic receptors for androgens were analyzed in thyroidectomy specimens from 31 patients. Fourteen specimens were from male and 17 from female patients. The specimens included five papillary carcinomas, five follicular adenomas, 15 colloid goiters, and six relatively normal thyroid tissues. All assays were performed by a protamine sulfate precipitation technique and analyzed by the method of Scatchard. Selected specimens were analyzed by sucrose density gradient. A receptor content greater than 1 fmol/mg cytosol protein was taken as positive if the dissociation constant was less than 1 nm. Seventeen of 31 specimens were positive for androgen receptors, with a dissociation constant of 0.26 +/- 0.09 X 10(-10) M and a receptor content of 11.20 +/- 4.77 fmol/mg cytosol protein. Four of five carcinomas, four of five adenomas, and nine of 21 benign thyroid tissues were positive for androgens. These androgen receptors are a single class with high affinity that are saturable and precipitate at the 6S (Svedberg unit) region similar to receptors in other androgen-dependent tissue. The data suggest that physiologic androgenic milieu may influence the growth of thyroid tumors.

Comparative study of protease inhibitors on coagulation abnormalities in canine pancreatitis

Coagulation abnormalities induced by pancreatitis were studied in 36 dogs. The 12 dogs in group I underwent a duodenotomy alone. The six dogs in groups II, III, IV, and V had pancreatitis induced by bile injection (1 cc/kg) into the pancreatic duct. Twenty minutes after bile-induced pancreatitis, group III was given 1.0 mg/kg aprotinin (trasylol), group IV was given 10 mg/kg S-2441, a new synthetic protease inhibitor, and group V was given 0.5 mg/kg alpha 2-antitrypsin by intravenous infusion over 10 min. Blood was drawn for amylase, protime (PT), partial thromboplastin time (PTT), fibrinogen, and platelets, in addition to markers of hypercoagulation, fibrinopeptide A, and antithrombin III, and markers of fibrinolysis, B beta 15-42 immunoreactive peptide (IP), and alpha 2-antiplasmin at baseline, 1/2, 1, 3, 6, 24, 48, and 72 hr after duodenotomy or bile injection. There was no significant difference in PT, platelets, antithrombin III, and fibrinopeptide A among the five groups. With the induction of pancreatitis (group II), serum amylase was significantly elevated but fibrinogen only became elevated at 24 hr and PTT at 48 hr. The increase in B beta 15-42 IP seen 30 min after induction of pancreatitis and the decrease in alpha 2-antiplasmin were blunted by aprotinin, alpha 1-antitrypsin, and S-2441, but inhibition of the rise in amylase and B beta 15-42 IP only reached significance with S-2441 (P less than 0.05). Pancreatitis-induced fibrinolysis was inhibited by S-2441 suggesting that synthetic protease inhibitors may play a therapeutic role in pancreatitis.

Effects of protease inhibitors on coagulation abnormalities in acute canine pancreatitis

Coagulation abnormalities associated with severe pancreatitis were studied in 24 dogs. Group I consists of six control subjects who had duodenotomy alone. Group II consists of six dogs with pancreatitis induced by bile injection ( lcm3 /kg) into the pancreatic duct. The six dogs in Group III and the six in Group IV were given aprotinin (trasylol) 1.0 mg/kg and S-2441 (10mg/kg), a new synthetic protease inhibitor, respectively. These were given over 10 minutes by intravenous infusion, 20 minutes after bile induced pancreatitis. Blood was drawn for amylase, prothrombin time (PT), partial thromboplastin time (PTT), fibrinogen, and platelets, in addition to markers for hypercoagulation, fibrinopeptide A, antithrombin III, and markers for fibrinolysis, B beta 15-42 immunoreactive peptides and alpha 2 antiplasmin at baseline, 30 minutes, 1 hour, 3 hours, 6 hours, and daily for 3 days after injection of bile or duodenotomy. There was no significant difference in PT, platelets, antithrombin III, and fibrinopeptide A among the four groups. Fibrinogen levels and PTT were minimally elevated in animals with bile induced pancreatitis, but these changes reached significance only at 24 hours and 48 hours, respectively (P less than 0.05). Immunoreactive B beta 15-42 became elevated at 30 minutes indicating fibrinolysis in animals with pancreatitis, and these changes were significant compared with Group I control subjects (P less than 0.05) throughout the study. Levels of alpha 2 antiplasmin were decreased in Group II animals with pancreatitis, which also suggests fibrinolysis. Amylase was elevated in Group II animals with pancreatitis (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Blood transfusion in cadaveric renal transplantation-a prospective study

177 consecutive primary cadaveric renal transplantations were performed during April 1977-October 1980 in our centre. The graft survival in 58 recipients who were transfused with two units of blood for "immunological" reasons was the same as for 107 patients transfused with 1-96 units for medical reasons prior to transplantations. Twelve non-transfused patients had a significantly lower graft survival than the transfused ones (p less than 0.01). No additional beneficial effect of transfusions exceeding two in number was found. When three or more units of blood were given peroperatively to earlier transfused recipients, a lower early graft loss due to rejection was demonstrated than when two or less units were administered. The risk of sensitization of the recipient after two units of leucocyte poor blood was low.

Mediation of macrophage collagenase production by 3'-5' cyclic adenosine monophosphate

The production of collagenase by lipopolysaccharide-(LPS) activated guinea pig macrophages is mediated by prostaglandins (PG) of the E series. After stimulation of guinea pig macrophages with LPS, extracellular PGE levels and cellular cAMP levels are elevated. Indomethacin inhibits not only PG synthesis, but also cAMP and collagenase production in LPS-stimulated macrophage cultures. In these indomethacin-inhibited cultures containing LPS, dibutyryl (dB) cAMP, or cholera toxin can restore macrophage collagenase production but not PG synthesis. Moreover, dBcAMP and cholera toxin enhance collagenase production in LPS-activated cultures. Initial activation of the macrophages by an agent such as LPS is a prerequisite for synthesis of collagenase, since in the absence of LPS, dBcAMP or cholera toxin alone are ineffective stimuli. These findings clearly demonstrate a role for PG-induced elevations of cAMP in the production of collagenase by LPS-activated macrophages.

Mediation of macrophage collagenase production by 3'-5' cyclic adenosine monophosphate

The production of collagenase by lipopolysaccharide-(LPS) activated guinea pig macrophages is mediated by prostaglandins (PG) of the E series. After stimulation of guinea pig macrophages with LPS, extracellular PGE levels and cellular cAMP levels are elevated. Indomethacin inhibits not only PG synthesis, but also cAMP and collagenase production in LPS-stimulated macrophage cultures. In these indomethacin-inhibited cultures containing LPS, dibutyryl (dB) cAMP, or cholera toxin can restore macrophage collagenase production but not PG synthesis. Moreover, dBcAMP and cholera toxin enhance collagenase production in LPS-activated cultures. Initial activation of the macrophages by an agent such as LPS is a prerequisite for synthesis of collagenase, since in the absence of LPS, dBcAMP or cholera toxin alone are ineffective stimuli. These findings clearly demonstrate a role for PG-induced elevations of cAMP in the production of collagenase by LPS-activated macrophages.

Relationship of pityriasis amiantacea to psoriasis. A follow-up study

46 patients with pityriasis aminantacea have been reexamined with regard to the later development of psoriasis and atopic diseases, and their occurrence in first and second degree relatives. HLA antigens of the A, B and C series were also determined. Earlier suggestions of a close association with psoriasis were not confirmed. An association with atopic diseases could not be established. Occurrence of seborrheic dermatitis seems, however, common in patients with pityriasis amiantacea.

Renal graft rejection and blood transfusion before and during the transplant operation

The outcome of 390 consecutive primary cadaveric renal transplantations in a single centre was studied with regard to blood transfusions before and during the transplant operation. The graft loss due to rejection was 38% at 12 months in the transfused group compared to 67% in the non-transfused group (p less than 0.0005). When peroperative transfusions were added to patients in the previously transfused group, the graft loss was reduced to 34% compared to 50% if no peroperative blood was given (p less than 0.05).