Sinus floor augmentation with simultaneous placement of dental implants using a combination of deproteinized bone xenografts and recombinant human osteogenic protein-1. A histometric study in miniature pigs

Maxillary sinus floor augmentation with autogenous bone has become a widely accepted procedure in implant dentistry. The use of osteoconductive bone substitutes in this indication is controversial, since their use can lead to a prolonged healing time, inhomogenous ossification, foreign body reaction, migration of particles and low bone-implant contact (BIC). The purpose of this study was to examine whether the combination of an osteoinductive protein (recombinant human osteogenic protein-1 (rhOP-1 = bone morphogenetic protein-7) with natural bovine bone mineral (BioOss) would improve ossification and the bone-implant contact (BIC) in a sinus floor augmentation with simultaneous placement of implants. In this study, the maxillary sinus floors in 5 miniature pigs were augmented with 3 ml BioOss containing 420 micrograms rhOP-1 on the test side and 3 ml BioOss alone on the control side. At the time of augmentation a titanium implant (ITI) was inserted from a laterocaudal direction. After 6 months of healing the sites of augmentation were removed and examined in non-decalcified sections by microradiography, fluorescence microscopy of sequentially labelled specimens and by histometry. On both sides, significant amounts of newly-formed bone were observed. However, on the test sites, the percentage of BIC in the augmented area was 80.0% versus 38.6% on control sites. It can be concluded that the application of bone morphogenetic proteins caused a more rapid and enhanced osseointegration of simultaneously placed implants when compared to the bone substitute alone. Therefore recombinant human osteogenic protein-1 delivered by natural bone mineral has the potential to become a clinical alternative for autogenous bone grafts in sinus floor augmentation.

Association of (Q)R/KRAA positive HLA-DRB1 alleles with disease progression in early active and severe rheumatoid arthritis

OBJECTIVE

We have shown that HLA-DRB1 alleles influence inflammatory activity in patients with early active and severe rheumatoid arthritis (RA). Therefore, we analyzed the effect of HLA-DRB1 alleles on disease progression in patients with early RA during a clinical followup period of 18 months.

METHODS

Disease progression was defined by the Larsen Score, the Ritchie Index (RI), and the Health Assessment Questionnaire (HAQ) score.

RESULTS

Patients carrying arthritogenic HLA-DRB1 alleles on one or both haplotypes are characterized by increased radiological joint destruction (Larsen Score). Further, (Q)R/KRAA homozygous patients were characterized by worse overall disease course (higher RI and HAQ). However, analysis of changes in joint effects (delta-RI) and personal disability (delta-HAQ) did not reveal significant differences between patients with or without disease associated HLA-DRB1 alleles.

CONCLUSION

The predisposing genetic pattern with disease associated HLA-DRB1 alleles did not profoundly influence the therapeutic outcome. Our data support the role of the HLA-DRB1 gene locus in disease modulation of RA. The genetic predisposition due to HLA-DRB1, however, may have only a limited influence on the therapeutic outcome in clinically severe cases of RA.

Ultrasensitive bienzyme sensor for adrenaline

A biosensor consisting of an analyte-recycling two-enzyme system using laccase (Coriolus hirsutus) and PQQ-dependent glucose dehydrogenase in combination with the electrochemical detection of oxygen depletion at a platinum electrode was used for adrenaline determination in the nano- and subnanomolar concentration range. Measurements were performed in a flow cell providing excellent baseline stability and fast recovery of the sensor. Improved design of the polymer matrix resulted in a lower detection limit of 200 pmol/l for adrenaline. The sensor has successfully been applied to the analysis of adrenaline in effluate of isolated rabbit hearts.

Extraamniotic saline infusion is promising in preparing the cervix for induction of labor

BACKGROUND

The application of local prostaglandins before induction of labor in women with an unripe cervix is standard procedure in Sweden. Side effects include uterine hypertonus and occasionally fetal heart rate abnormalities. Failed ripening is reported in up to 25% of cases. A previous report of ripening of the cervix by use of extraamniotic physiologic saline infusion through a Foley catheter applied in the cervix claimed results superior to topical prostaglandins.

OBJECTIVE

To conduct a prospective randomized trial of extraamniotic saline infusion and intracervical application of dinoprost 0.5 mg on cervical ripening and outcome of labor.

METHODS

Eighty-five term singleton pregnant women with unripe cervices where induction of labor was indicated were randomized to prostaglandin or saline infusion after obtaining informed consent. Outcome variables were improvement of cervical score, induction delivery time and mode of delivery.

RESULTS

The 42 women in the saline infusion group obtained significantly (p < or = 0.001) higher cervical scores and shorter induction delivery intervals (p < or = 0.005) than the 43 women in the prostaglandin group. Cases of unripe cervix after 24 hours were significantly (p < or = 0.01) fewer in the saline group. There were more Cesarean sections in the saline group, but this difference was not significant. Saline infusion did not induce uterine activity and oxytocin was given in every case after the expulsion of the catheter.

CONCLUSIONS

In this study extraamniotic saline infusion was a more efficacious method for ripening of the cervix than intracervical prostaglandin. The absence of early painful contractions is an advantage, but effective stimulation of labor is required to effect delivery after maturation of the cervix.

HLA-DR/DQ/DP interactions in rheumatoid arthritis

Rheumatoid arthritis (RA) is associated with the presence of particular HLA-DRB1 alleles. In order to characterize HLA-DQB1 and/or-DPB1 alleles that contribute to disease susceptibility besides HLA-DRB1 alleles, we have analysed the HLA-DRB1, -DQB1 and -DPB1 polymorphism in 84 RA patients and 135 controls. HLA typing for HLA-DRB1 and -DQB1 alleles was performed using sequence-specific primers in combination with sequence-based typing. HLA-DPB1 alleles were characterized by reverse dot-blot hybridization. Our data confirm the predominant role of the (Q)R/KRAA sequence from AA position 70-74 of the HLA-DRB chain for disease susceptibility. In particular, the lysine (K) substitution at position 71 was highly significantly associated with RA. Analysis of the DQB1 locus revealed no association with RA when linkage disequilibrium between HLA-DRB1 and -DQB1 alleles was considered. In contrast, we observed an increased frequency of HLA-DPB1*0401 among (Q)R/KRAA-positive patients. (Q)R/KRAA-negative RA patients exhibited an overrepresentation of HLA-DPB1*0201 and HLA-DPB1*0601. Rheumatoid factor (RF) production correlated with the presence of the disease-associated (Q)R/KRAA amino acid cassette of the HLA-DRB chain. When HLA-DPB1 allele frequencies were compared between RF-positive and RF-negative RA patients, we observed an increased frequency of HLA-DPB1*0401 among RF-positive RA patients and HLA-DPB1*0201 among RF-negative patients. These results suggest that besides the predominent role of HLA-DR molecules in RA, HLA-DP molecules may have an influence on disease susceptibility and could modulate disease progression. HLA-DPB1*0401 may function in addition to HLA-DRB1*04, whereas HLA-DPB1*0201 and -DPB1*0601 may represent additional risk factors among (Q)R/KRAA-negative RA patients.

HLA-DRB1*04 subtypes are associated with increased inflammatory activity in early rheumatoid arthritis

The sequence polymorphism of HLA-DRB1 molecules in 84 rheumatoid arthritis (RA) patients with early RA has been analysed to evaluate whether particular HLA-DR alleles influence disease progression in the early stage of the disease. Clinical data were analysed by grouping the patients according to disease-associated haplotype combinations (DRB1*04,04/DRB1*04,01/DRB1*04,X/DRB1*01,X) in comparison to patients who did not carry these haplotypes (DRB1*X,X). Our results indicate that patients with early RA who are homozygous for DRB1*04 exhibit an elevated inflammatory activity and an increase of joint affections. In addition, the amino acid polymorphism (QR/KRAA) at position 70-74 seems to affect the production of rheumatoid factors. These results support the role of HLA-DRB1 alleles in the pathogenesis of RA and indicate that patients with particular HLA-DRB1*04 haplotype combinations may require intensified therapeutic interventions in the early stage of the disease to prevent disease progression.

Amperometric lactate oxidase catheter for real-time lactate monitoring based on thin film technology

An amperometric lactate oxidase catheter has been developed for in vivo application to real-time lactate monitoring. The electrochemical behaviour of the 1 x 3 mm Pt-Ag/AgCl thin film electrode is not significantly influenced by lactate oxidase-polyurethane covering. Gamma-irradiation (25 kGy) is suitable for the sterilization procedure. The final lactate catheter is characterized by a linear concentration range between 0.5 and 20 mmol/l lactate with a sensitivity around 2 nA mmol-1 l-1 lactate. The accuracy is demonstrated by the measurement of control sera. Both physiological and pathological materials correlate well with the declared values. The dry stored lactate catheter needs about 10 min for hydration and is characterized by response times t98% of less than 2 min. Ex vivo whole blood measurements using the lactate catheter (y) give a correlation with the BIOSEN Med L (x) of y = (1.010x + 0.513) mmol/l (r = 0.9748). Lactate values obtained by continuous catheter operation ex vivo correlate well with those obtained by BIOSEN Med L. First subcutaneous implantation (dog) underlines the characteristics obtained ex vivo: after 30 min hydration the lactate catheter follows the lactate concentration measured ex vivo with samples from the leg vein by BIOSEN Med L.

A simple method for preoperative assessment of the best fitting electrode length in single lead VDD pacing

For single lead VDD pacing, electrodes with various distances between the lead tip and the floating atrial dipole (AV distance) are available. Using different AV distances allows positioning of the atrial dipole in the mid- to high right atrium, regardless of the size of the right heart. In this position, reliable atrial sensing and rejection of ventricular far-field potentials can be expected. A simple test for the preoperative assessment of the best fitting AV distance in the individual patient was tested. We studied 24 consecutive patients prior to implantation of a VDD pacemaker. With the patient in supine position, a test electrode with an AV distance of 13 cm was taped onto the thorax. Under fluoroscopic control, it was moved until its course and projection onto the heart was equal to that of a ventricular lead. If fluoroscopy then showed a projection of the atrial dipole onto the mid- to high right atrium, a lead with a similar AV distance of 13 or 13.5 cm was used for implantation. If the atrial dipole projected itself too high or too low, a shorter or longer lead had to be implanted. The maximum time for the test was 2 minutes, and the maximum fluoroscopy time was 15 seconds. According to the test, a lead with an AV distance of 13 or 13.5 cm was implanted in 18 of 24 patients, and a lead with an AV distance of 15.5 or 16 cm was implanted in 6 of 24 patients. The atrial dipole could easily be positioned in the mid- to high right atrium in all patients, demonstrating a correct preoperative assessment of the best fitting AV distance. Intraoperatively, a P wave amplitude of 3.5 +/- 3.0 mV was measured. The described test allows a fast and reliable assessment of the best fitting electrode length in single lead VDD pacing.

Soluble tumor necrosis factor (TNF) receptors conserve TNF bioactivity in meningitis patient spinal fluid

The content of tumor necrosis factor (TNF)-alpha antigen and the bioactivity of soluble TNF receptor type II (sTNF-RII) in cerebrospinal fluid (CSF) from 29 patients with meningeal symptoms and fever were examined. Immunoreactive TNF was demonstrated in CSF from 4 of 7 patients with bacterial meningitis. In 3 of 8 patients with aseptic meningitis, CSF also contained TNF, but TNF bioactivity was confined to samples from patients with bacterial meningitis. Bioactive TNF was exclusively in high-performance liquid chromatography fractions containing 30- to 60-kDa proteins. Lipopolysaccharide induced down-regulation, possibly after shedding of granulocyte surface membrane TNF-RII. Consistently, there was a statistically significant correlation between sTNF-RII and CSF leukocyte counts. Bioactive TNF was found only in CSF containing >1 ng of sTNF-RII/mL; samples without TNF bioactivity contained less sTNF-RII. Thus, a stabilizing effect of sTNF-RII on the oligomeric cytokine in vivo is plausible.

Sodium and dopamine excretion in prehypertensive Dahl rats during severe hypervolaemia

As opposed to the salt-resistant Dahl-R rat the salt-sensitive Dahl-S has a defective renal dopamine DA1 receptor that may be involved in its susceptibility to develop hypertension during a high salt diet. To compare the ability of prehypertensive Dahl-R and Dahl-S to respond to a severe isotonic sodium load, renal function was monitored during a severe form of acute isotonic volume expansion (10% VE). Mean arterial blood pressure before VE was similar in Dahl-R and Dahl-S and decreased in both strains by 6% during VE. The accumulated sodium excretion during VE in Dahl-R was 411 +/- 64 micromol 100 min(-1) g(-1) kidney wt (kw) which was not different from that in Dahl-S (420 +/- 95 micromol 100 min(-1) g(-1) kw). The accumulated dopamine excretion (a mirror of renal dopamine synthesis) during VE was also similar in Dahl-R (134 +/- 13 ng 100 min(-1) g(-1) kw) and Dahl-S (126 +/- 16 ng 100 min(-1) g(-1) kw). The excretion of DOPAC, the main metabolite of Dahl-S, glomerular filtration rate and systemic haematocrit did not differ between the strains before, during or after VE. To conclude, in spite of a defective renal DA1 receptor prehypertensive Dahl-S do not respond with an attenuated natriuretic or dopamine excretory response when subjected to a severe isotonic sodium load. The results do not support a sodium retaining role over a defective DA1 receptor in the salt-sensitive hypertension in Dahl-S.

[Promoting competence in a model trial of a complementary course of study in health sciences/public health at the Berlin Technical University in cooperation with the Free University and other science and general practice institutions]

Since October 1992 (winter semester 92/93) graduates are being educated in Public Health at Berlin Technical University in cooperation with the Free University of Berlin as well as with the Humboldt University of Berlin and other institutions of science and practice in Berlin and Brandenburg. For the time being the course of studies is a pilot project for 4 years. The aim of the postgraduate studies is the creation of permanent structures and therefore institutionalisation. It is open to graduates and college graduates of public-health relevant subject areas of specialisation are "Health Promotion in the community and at the workplace" and "Planning and Management in Health Services". The course of studies takes 4 semesters and is divided into basic studies, studies of main points of emphasis and project studies. Social medicine and especially epidemiology are part of the basic disciplines, which are indispensable for finding the way of looking at problems concerning public health. The reason for the peculiarity with regard to establishing public health at other German universities are the main topics representing the interaction between the technical and ecological development of health. The graduate degree is "Magister of Public Health". During the time of the pilot project the course of studies is subjected to external and internal surveillance regarding quality assurance and quality optimisation of teaching and organisation of the studies. On the one hand this is done by an external advisory committee and on the other hand by internal and external evaluation.

Effect on human teeth of renal transplantation: a postmortem study

Extracted teeth from five deceased patients treated by renal transplantation were examined radiographically and histologically, and compared with teeth from healthy persons of approximately the same age. In three of the patients with a renal transplant, the radiographs showed normal pulp chamber sizes, but histologic examination revealed a widened predentin zone, approximately four times greater than in the controls. In two of the patients the radiographs showed marked reduction of the pulp chamber size. The histologic changes of these teeth were mainly an extensive amount of secondary dentin along the pulp chamber walls and the root canals, with a markedly reduced pulp space. One explanation for the difference between the patients was that patients with extensive pulp calcifications were given a higher total amount of corticosteroids than patients with a widened predentin zone.

High level expression of functional full length human thyroid hormone receptor beta 1 in insect cells using a recombinant baculovirus

We have cloned the human thyroid hormone receptor beta 1 (hThR beta) from the human breast cancer cell line T47D using the PCR technique. A recombinant baculovirus transfer vector pVL1392/hThR beta was constructed and the full length receptor was expressed in the insect cell line Spodoptera frugiperda (Sf9). Approx. 10-15 x 10(6) receptors are expressed/cell which implies a production level of 2.5-4.0 mg hThR beta/l of cell culture. The expressed hThR beta displayed a single class of binding sites for T3 with high affinity. Western blot analysis using a polyclonal antibody indicated that the molecular weight of the baculovirus expressed receptor is approx. 50 kDa. Crude nuclear extract of hThR beta labeled with [125I]T3 sedimented as a 4 S peak on a glycerol gradient. No receptor could be detected in the cytoplasm indicating its proper translocation to the nuclear compartment. An oligonucleotide containing a palindromic thyroid hormone response element is specifically recognized and retarded in a gel-mobility-shift assay in the presence of nuclear extract of Sf9 cells expressing hThR beta. These data suggest that hThR beta expressed in Sf9 cells is functional and displays characteristics virtually indistinguishable from those of the thyroid hormone receptor (ThR) extracted from mammalian cells. Furthermore, the data indicate that the baculovirus expression system is adequate for large-scale production of receptor for detailed structural and functional studies.

Glycoproteins of rat liver plasma membranes: their hepatocellular, intestinal and renal expression in rat, rabbit and human

Expression of six glycoproteins (Mr = 60,000 (gp 60), 80,000 (gp 80), 110,000 (gp 110), 120,000 (gp 120), 140,000 (gp 140), 160,000 (gp 160)) recently purified from rat liver plasma membranes (LPM) were compared in the liver, small intestine and kidney of the rat, rabbit and human. Immunoblotting studies with monospecific antisera showed that five of the six glycoproteins (gp 60, gp 80, gp 110, gp 120, and gp 140) were expressed not only in LPM of the rat but also in LPM from the rabbit and human with Mr corresponding to those of the glycoproteins isolated from the rat. In contrast, the glycoprotein gp 160 was only detected in rat liver. The same pattern of expression was found by immunofluorescence on isolated hepatocytes from the three species. In rat liver, the glycoproteins were localized primarily either in the bile canalicular domain (gp 80, gp 110, gp 120), or in the sinusoidal domain (gp 60, gp 140), or they were distributed over the whole hepatocellular surface (gp 160). In rat, but not in rabbit or human, the glycoproteins gp 110, gp 120 and gp 140 were also found in the small intestine localized either in the brush border membrane (gp 110, gp 120) or over the whole surface membrane of enterocytes (gp 140). Gp 120 was also detected in the luminal pole of tubular epithelial cells of rats kidney. The data show that LPM of different mammalian species share several common glycoprotein antigens. These glycoproteins, that are also partly expressed in extrahepatic tissues, may represent plasma membrane structures conserved among mammalian species.

Ursodeoxycholic acid-induced changes of plasma and urinary bile acids in patients with primary biliary cirrhosis

Ursodeoxycholic acid treatment of patients with primary biliary cirrhosis may lead to relief of pruritus and improvement of biochemical liver tests. The changes in serum and urinary bile acids induced by ursodeoxycholic acid treatment were studied. After 29 patients with primary biliary cirrhosis were treated with ursodeoxycholic acid (750 to 1,000 mg/day) for 6 to 12 mo because of an increase in ursodeoxycholic acid, total plasma bile acids increased from 30.5 +/- 6 mumol/L (mean +/- S.E.M.) to 52.7 +/- 11.7 mumol/L (p less than 0.01). The increase in total plasma bile acids correlated significantly with concentrations of plasma bile acid before treatment (p less than 0.01). The concentrations of endogenous bile acids decreased, mainly because of a decrease of cholic acid. During treatment, glycine conjugation increased and taurine conjugation decreased, whereas sulfation and glucuronidation of bile acids were unchanged. In 10 patients with primary biliary cirrhosis in stages III and IV, urinary excretion of bile acids was also studied. After treatment, ursodeoxycholic acid and its 3-beta isomer and C-1-hydroxylated and C-6-hydroxylated derivatives were also excreted. During treatment, urinary excretion of endogenous bile acids decreased. The increase of ursodeoxycholic acid and the decrease of endogenous bile acids may both be related to the improvement of biochemical liver tests in precirrhotic stages of the disease. In cirrhosis, endogenous bile acids in plasma remained high and changes in liver tests were small.

[Long-term treatment of cryptogenic hepatitis C using recombinant interferon alpha]

In a pilot study 15 patients with cryptogenic chronic hepatitis non-A, non-B received human recombinant interferon alpha (rIFNa) at a dosage of 5 million units 3 times per week for periods of up to 4 months, followed by an additional 4-month course of treatment with 2 million units 3 times per week after an observed reduction in serum aminotransferase levels. Ten of the 15 patients demonstrated antibodies to hepatitis C virus (HCV). Pretreatment histological examinations revealed evidence of chronic aggressive hepatitis in 12 patients, 4 with signs of cirrhosis, and chronic persistent hepatitis (CPH) in the remaining 3 cases. Normalization of serum aminotransferase levels was documented in 9 patients (7 anti-HCV-positive), and a significant reduction occurred in 2 additional anti-HCV-positive cases. Follow-up biopsy at 8 months in 7 of the 11 responders documented improved histological findings in every case. Five patients with CAH in the initial study had discrete residual portal inflammation or mesenchymal reaction in the second histological examination. Clinical follow-up is currently at 12 month, and 3 anti-HCV-positive responders have normal aminotransferase levels. The data show that a subset of patients with chronic hepatitis C will demonstrate remission of disease after an 8-month course of treatment with rIFNa.

Guinea pig maximization test with a polyether impression material

Adverse reactions to a polyether rubber impression material introduced in the mid-sixties have been reported in the literature. Most of the reports are inconclusive regarding the distinction between allergic and toxic responses. The aim of this study was to assess the allergenic potential of this material using a guinea pig maximization test. Ten guinea pigs in the experimental group were sensitized in two steps. First, an extract of the material was injected intradermally, and 7 days later, the material mixed in petrolatum was applied topically. After another 2 wk test solutions were applied, and the skin response was evaluated by visual inspection. Ten nonsensitized animals served as controls. From the challenge test it was evident that the catalyst as well as the freshly mixed material elicited positive skin reactions interpreted as being delayed hypersensitivity reactions. The findings indicate that the material contained substances which could be classified as strong to extreme sensitizers. Some of the adverse reactions seen in connection with the use of this material might well be related to delayed hypersensitivity reactions.

Experimental liver membrane antibodies (LMA) and antibodies against "liver specific protein (LSP)"--a comparative in vitro study

Experimental antisera against the 26 kD rat liver protein--recently defined as a target antigen of LMA--and against "LSP" were tested on tissue sections and isolated hepatocytes from rat as well as with a variety of subcellular fractions as antigens. Anti-26 kD protein resulted in sharp immunofluorescence staining of hepatocellular plasma membranes in liver sections and on isolated hepatocytes, while the antiserum did not react with intracellular structures and was also negative with tissue sections from kidney and heart. Anti-"LSP" stained the plasma membranes of isolated hepatocytes, the cytoplasma of liver and kidney sections as well as the connective tissue of heart sections. In Western blot studies anti-26 kD protein showed a single band at 26 kD when liver plasma membranes and soluble liver protein fractions were used as antigens; a weak reaction was observed with microsomes and soluble kidney protein fractions, but there was no reaction with mitochondria or soluble heart proteins. Anti-"LSP" reacted with various proteins of the subcellular fractions between 16 and 116 kD. The 26 kD protein was found in peak II of Sepharose 6B chromatography of soluble liver protein fractions but was absent in the "LSP" fraction (peak I). We conclude that experimental LMA and anti-"LSP" recognize different epitopes of the hepatocellular plasma membrane.

Long-term follow-up of posttransfusion and sporadic chronic hepatitis non-A, non-B and frequency of circulating antibodies to hepatitis C virus (HCV)

The natural course of chronic hepatitis non-A, non-B (HNANB) was documented for 3-20 yr (mean 8 yr) in 86 patients, who attended our special ambulance between 1981 and 1988. Sixty five of the 86 patients (75%) were positive for circulating antibodies against hepatitis C virus (HCV) (anti-HCV). Twenty four patients had chronic posttransfusion (PT)-HNANB (18 anti-HCV-positive; 75%), and 62 patients had sporadic (S)-HNANB (47 anti-HCV-positive; 75%). Twenty nine per cent of patients with chronic PT-HNANB had sustained normalization of aminotransferases after a period up to 5 yr, 55% demonstrated chronic persistent hepatitis (CPH) and 16% progressed to chronic active hepatitis (CAH) with transition to cirrhosis. In the group with chronic S-HNANB, 2% of patients showed remission, 43% had stable CPH and 55% progressed to CAH or cirrhosis. However, development of cirrhotic complications required many years. Transition from CAH to CPH or remission was not observed. The results indicate that 75% of both patients groups with chronic PT- and S-HNANB are infected with the same agent, of which antibodies are detected by the new anti-HCV assay. There was no statistical association between the severity of the disease and the presence of anti-HCV. The different proportions of progressive courses in chronic PT- and S-HNANB might be explained by the patient recruitment.