Early development of therapeutic biologics--pharmacokinetics

Modern biologics are biotechnology-derived pharmaceuticals. They are mostly used for diagnosis, prevention and treatment of serious and chronic diseases. Today, therapeutic biologics range from traditional biologics like blood and blood components, fractionated blood products, and antitoxins to modern biologics such as monoclonal antibodies, cytokines (e.g. interferon, interleukine), tissue growth factors, vaccines directed against non-infectious disease targets, and gene transfer products. Chemical as well as pre-clinical development are major challenges for biologics due to their different physicochemical properties (mostly protein structure) compared to small molecules. They demonstrate much more complex pharmacokinetic behaviour, which strongly influences their pre-clinical testing strategy. Biologics are often highly species-specific in action and immunogenic in test animal species and humans. Immunogenicity of therapeutic biologics may influence their pharmacokinetic behaviour as well as pharmacodynamics and toxicity. Biologics are frequently regulated by different procedures compared to small molecules. New guidances are evolving which reflect the rapid development of new technologies in this field. Bioanalytical method development and validation is a prerequisite not exclusively for pharmacokinetic studies but for the whole pre-clinical and clinical development. Due to their unique properties, different kinds of bioanalytical assays (mass assays, activity assays, immunogenicity assays) are necessary in early development of biologics.

Surgical Conversion of Abdominal Aortic Stent-grafts—Outcome and Technical Considerations

OBJECTIVE

The purpose of this study was to evaluate the outcome of patients with stented abdominal aortic aneurysms who had to undergo open aneurysm repair with partial or total stent-graft removal.

METHODS

Between October 1996 and December 2003, 117 patients with abdominal aortic aneurysms underwent endovascular repair. When open surgery was necessary during the initial and same anaesthesia as stent-graft implantation, it was defined as immediate conversion. When conversion was performed during a second anaesthesia, we defined it as late (acute or elective) conversion.

RESULTS

A total of 33 patients underwent conversion to open surgery. In 7 (6%) patients, immediate conversion was necessary due to stent-graft misplacement and obstruction of the renal arteries (n=4), type Ia endoleaks (n=2) and stent-graft dislocation into the aneurysm sac (n=1). During a mean follow-up period of 39.6 months (min 0.03 months, max 80.4 months), 26 (23.6%) of the remaining 110 patients underwent late conversion to open surgery for endoleak (n=12), rupture (n=6), thrombosis (n=4), graft fatigue (n=2), aorto-duodenal fistula (n=1), and recurring peripheral embolisms (n=1). The mortality of acute conversion was 38% (5 of 13). Elective conversion did not lead to any mortality.

CONCLUSION

Acute conversion of stented abdominal aortic aneurysms is associated with a high mortality. Elective stent-graft explantation with open aortic reconstruction is a safe but complex procedure.

Cement embolization into the vena cava and pulmonal arteries after vertebroplasty: interdisciplinary management

PURPOSE

To report interdisciplinary management in a case of cement embolization into the inferior vena cava and peripheral pulmonary arteries after percutaneous vertebroplasty.

CASE REPORT

A 50-year-old female patient with an osteoporotic compression fracture of the second lumbar vertebra underwent percutaneous vertebroplasty with polymethylmetaacrylate. Thereafter, CT scanning revealed small asymptomatic cement emboli in peripheral pulmonary arteries, along with a hook-shaped cement fragment in the inferior vena cava. Due to the risk that the large cement fragment could migrate to the pulmonary arteries and cause serious complications, they were retrieved from the inferior vena cava by an endovascular technique and extracted through a surgical groin incision. The patient received anticoagulant treatment for 3 months and is free of complaints after 1 year.

CONCLUSION

This case shows that this rare complication following vertebroplasty can be successfully managed with an interdisciplinary approach.

Thrombolysis in stroke patients aged 80 years and older: Swiss survey of IV thrombolysis

This databank-based, multicenter study compared all stroke patients with IV tissue plasminogen activator aged > or = 80 years (n = 38) and those < 80 years old (n = 287). Three-month mortality was higher in older patients. Favorable outcome (modified Rankin scale < or = 1) and intracranial hemorrhage (asymptomatic/symptomatic/fatal) were similarly frequent in both groups. Logistic regression showed that stroke severity, time to thrombolysis, glucose level, and history of coronary heart disease independently predicted outcome, whereas age did not.

Age related change of optokinetic nystagmus in healthy subjects: a study from infancy to senescence

BACKGROUND

Optokinetic nystagmus (OKN) gain is asymmetrical between temporal to nasal (TN) and nasal to temporal (NT) stimulation in infancy and decreases at older ages. The age at which OKN gain becomes symmetrical and decreases is debated. The aim was to investigate OKN over the whole lifespan in a large sample of healthy subjects.

METHODS

In a prospective, cross sectional study OKN was tested monocularly using TN and NT small field stimulation. Stimulation velocity was 15 degrees /s and 30 degrees /s for children aged under 1 year (n = 97), and 15 degrees /s, 30 degrees /s, 45 degrees /s, and 60 degrees /s for older subjects (1-9 years, n = 66; 10-89 years, n = 86). Gain was measured using infrared oculography.

RESULTS

Significant OKN gain asymmetry in favour of TN versus NT stimulation was found during the first 5 months of life (p<0.05). Only at 11 months of age was OKN symmetrical in 100% of the subjects. The percentage of children with symmetrical OKN decreased with increasing stimulus velocity. OKN gain increased in the second and third years (p<0.05 for 15 degrees /s), remained stable until 50 years of age, and showed a small but significant decrease afterwards for the tested velocities (between 6% and 18%, p<0.05).

CONCLUSIONS

Infrared oculography is an accurate method to assess OKN, especially in children. Knowledge about change of OKN in healthy subjects could be helpful to interpret OKN in patients with abnormal binocular vision or lesions of the central nervous system.

RN and RPN decision making across settings

Nursing decision making was a focus of the Province-Wide Nursing Project (PWNP), a 3-year project to promote best nursing practice. In much of the growing literature on nursing decision making, it is assumed that there are differences in the way RNs and RPNs make decisions. However, there is little scientific evidence to support this assumption. The RN and RPN decision making across settings questionnaire was completed by nurses employed in the 23 agencies of the 4 Participating Complexes taking part in the project. The survey questions were subjected to factor analysis and reduced to five factors. Results revealed measurable differences between the way that RNs and RPNs made decisions. Both RNs and RPNs reported making decisions frequently and experiencing little difficulty in making them. However, there were statistically significant differences in the frequency with which RNs and RPNs perceived they made decisions and the difficulty they found in making them. To plan effective health care, it is important to take account of the strengths of different health care workers. There is a need for further research to investigate the reasons behind the differences revealed in these findings.

Femoral artery infection associated with a percutaneous arterial suture device

This is a case report of a femoral artery infection with fatal outcome after using a percutaneous suture mediated closure device: A 77-year old patient underwent diagnostic angiography of his thoracic and abdominal aortic aneurysm, the puncture site was closed with the Perclose® system. He developed a staphylococcal femoral artery infection with groin abscess, requiring surgical intervention with debridement and removal of the Perclose® suture. After stent graft exclusion of the thoracic and abdominal aortic aneurysm a staphylococcal sepsis occurred and the patient died of aneurysm rupture months later despite long term antibiotic therapy. Since the use of the Perclose® device carries an increased risk of femoral artery infection with septic endarteritis and bacteremia, it should not be used in routine diagnostic angiography.

Cogan?s syndrome: clinical evolution of deafness and vertigo in three patients

The aim of this study was to evaluate the clinical symptoms, the otoneurological examinations, the treatment and the clinical course of three patients suffering from Cogan's syndrome, a rare disease based on the clinical association of a non-syphilitic interstitial keratitis with a cochleo-vestibular deficit. This case series involved three patients with follow up. The clinical course of the three patients (aged 30, 48 and 49 years) with Cogan's syndrome during a follow-up period of 2 to 6 years is reported. All patients underwent complete otoneurological, ophthalmologic and rheumatologic examinations and were treated with immunosuppressive therapy such as glucocorticoids and cyclophosphamide in two and glucocorticoids and methotrexate in one patient. Using immunosuppressive therapy, ophthalmologic symptoms disappeared rapidly in two patients. Hearing improved only in one and stabilized in a second patient. One patient died after 6 years of treatment because of complications of generalized vasculitis. Early diagnosis and rapid initiation of a combined immunosuppressive therapy such as corticosteroids and cyclophosphamide seem to be important in controlling the disease and avoiding persistent deafness. Whether systemic complications and a fatal outcome also can be prevented is still questionable.

Ruptur eines Aneurysmas der Arteria iliaca interna

Isolated aneurysms of the iliac arteries are rare. Located deep in the lesser pelvis, they are diagnosed late or in a symptomatic stage. Because of their manifold anatomic relationships to pelvic structures, iliac aneurysms may cause different symptoms such as obstipation, hydronephrosis, venous thrombosis, and entrapment neuropathy. Aneurysm rupture is associated with high mortality. The rupture of an iliac aneurysm into the rectum with massive lower intestinal bleeding is extremely rare. We report a patient with 6-year follow-up after aneurysm resection, extra-anatomic bypass, and suture repair of the rectum with temporary colostomy.

Health human resource planning in home care: how to approach it--that is the question

In her paper, MacAdam refers to future challenges in health human resources for the home-care sector. This paper builds on her comments and discusses conceptual and practical approaches to future planning of health human resources. Necessary national data requirements are identified for this type of planning. The authors point out the limitations of traditional supply-side modelling and describe a new framework linking population health needs to outcomes that builds upon earlier conceptual work in needs-based, utilization-based and effective demand-based models.

Follow-up study of treatment of orbital floor fractures: relation of clinical data and software-based CT-analysis

This retrospective study quantifies isolated orbital floor fractures using software-based CT-analysis and compares the clinical outcome across surgical and non-surgical treatment groups. Depending on the surgeon's interpretation of the clinical and radiological appearance, 10 fractures were treated non-surgically and 20 fractures surgically, either with antral balloon catheter alone or in combination with an orbital implant. Ophthalmologic findings were evaluated until 12 weeks after injury. Fracture area, and volume of displaced tissue (VDT) were assessed by software-based CT-analysis. VDT was marginally significantly smaller in non-surgically than in surgically-treated patients (P=0.08). Ophthalmologic findings improved in all groups during follow-up and no statistical difference was found between the groups. Diplopia remained moderate in three patients with balloon catheter alone, and minimal in four patients in both surgical groups. In one patient with non-surgical treatment, diplopia remained minimal after 12 weeks. Although CT-analysis revealed no significant difference between both surgical groups, patients treated with balloon catheter alone presented more diplopia after 12 weeks. Using balloon catheters for fracture repair a combined approach should be performed when large fractures involve the orbital floor to achieve sufficient reduction of orbital content and placement of an orbital implant. Software-based CT-analysis is helpful for objective interpretation in managing of orbital fractures.

Public attitudes towards people with mental illness in six German cities: results of a public survey under special consideration of schizophrenia

OBJECTIVES

Attitudes of the urban population in Germany towards people with mental illness were investigated in this study. The results are compared with those of attitude surveys conducted by other research centres participating in the World Psychiatric Association's (WPA) global anti-stigma-programme "Fighting Stigma and Discrimination because of Schizophrenia - Open the Doors" (WPA 1998).

METHODS

A total of 7246 German-speaking persons aged 16 and over were interviewed in private households in six German cities by telephone using a standardised questionnaire. The respondents were asked about their knowledge in regard to schizophrenia, their social distance towards people with schizophrenia and estimations of the social stigmatisation of mental patients in general.

RESULTS

33.1 % of the interviewees were able to name causes of schizophrenia. 76.5 % of the interviewees believe that people with schizophrenia often or very often need prescription drugs to control their symptoms. 81.1 % believe that most people would pass over the job application of a former mental patient in favour of another applicant.

CONCLUSIONS

Improvements in the education of the public about mental illnesses and provision of the opportunity for personal contact with mentally ill people are considered to be important measures for promoting the acceptance of the mentally ill by the public.

Cell-extracellular matrix interaction and physico-chemical characteristics of titanium surfaces depend on the roughness of the material

The interaction of cells with the extracellular matrix at the interface of an implant determines the biology of cells and tissues. We analysed components of cell adhesion and measured physico-chemical characteristics of structural modifications of titanium surfaces: polished, machined, glass particle-blasted, corundum-blasted, vacuum plasma-sprayed. Scanning electron microscopy and profilometry revealed a differentiated topography from smooth to rough surfaces, respectively. Osteoblastic MG-63 cells showed an increased spreading on surfaces with low roughness, although without a straight correlation with the surface topography. Integrin expression was increased on structured surfaces compared with polished material, and the organization of the actin cytoskeleton and fibronectin was impaired on extremely rough surfaces. Electrochemical methods, especially the electrochemical impedance spectroscopy (EIS) was used to evaluate physico-chemical characteristics, and the impedance curves revealed a dependence on the roughness of the material surfaces. Further analyses of the EIS results were performed using equivalent circuits which model the electrical flow through the interface. First indications for a correlation between parameters from the equivalent circuits with surface properties were obtained which promise a relevance for the biological response of the cells.

Orbital floor reconstruction with an alloplastic resorbable polydioxanone sheet

The orbital floor is frequently reconstructed after blow-out fractures or midface fractures to avoid a relapse of the repositioned orbital tissue and to prevent enophthalmos. A total of 31 patients underwent reconstruction of internal orbital wall fractures with a resorbable 0.25 mm or 0.5 mm-thick polydioxanone implant (PDS). Skeletal and functional outcome was evaluated retrospectively with regard to fracture size. Fracture size was graded as small, moderate or large by CT scans and operating records. Two of the 25 patients with small or moderate defects showed an enophthalmos of 2-3 mm. Five of the six patients with large defects or two orbital wall fractures had enophthalmos. The scar that formed after implant resorption was to weak to provide adequate support of the globe or to compensate the enlarged orbital volume. Endoscopic follow-up examination of 12 patients showed yielding of the scar in the orbital floor already in moderate defects. Eight patients had diplopia in extreme gaze and two had significant diplopia. Blow-out and midfacial fractures with small to moderate defects in the orbital floor (up to a size of 2.5 cm2) can be reconstructed by polydioxanone sheet to avoid enophthalmos. Polydioxanone implants should only be used in cases without massive orbital fat herniation. The scar formed after implant resorption may influence functional outcome.

[Attitude of the population to schizophrenic patients in 6 federal German large cities]

In a research project of the German Research Network on Schizophrenia, public attitudes towards people with schizophrenia were studied within a public education project. In six German cities, 7,246 persons aged 16 or older were interviewed in a telephone survey. Knowledge of schizophrenia, social distance, and proposals for activities to improve the public acceptance of mentally ill persons were inquired. Most of the persons interviewed expressed positive attitudes towards people with schizophrenia. Better public education about mental illnesses and the opportunity for closer contact to mentally ill persons were rated as important to improve the public acceptance of these individuals.

A computer-based method for calculation of orbital floor fractures from coronal computed tomography scans

PURPOSE

A computer program recently developed for the calculation of the orbital floor and fracture areas from coronal computed tomography (CT) scans was used in a study to evaluate the accuracy and ability of this new method.

MATERIAL AND METHODS

The size of orbital floors and fabricated fractures in 14 dried, anatomic specimens were measured in coronal CT scans by 3 independent observers. Based on this data set, the orbital floor and fracture regions were calculated with the newly developed computer program. These calculated regions were then compared with a direct measurement of the specimens that had been obtained by digital photography. The accuracy of the computer-based calculations was assessed using Lin's concordance correlation coefficient.

RESULTS

The size of the orbital floor (mean +/- SD) was found to be 5.21 +/- 0.39 cm(2) by direct measurement of the specimens and 5.30 +/- 0.52 cm(2) by calculation with the computer program. The region of the fracture (mean +/- SD) was 1.05 +/- 0.64 cm(2) by direct measurement and 1.01 +/- 0.62 cm(2) by computer calculation. The between-method mean difference (direct measurement minus computer based calculation) was -0.09 cm(2) (or 1.7% of mean orbital floor region) for orbital floor region and 0.04 cm(2) (or 3.8% of mean fracture region) for fracture region.

CONCLUSIONS

This accurate and time-saving method is practicable for determining the size and location of orbital floor fractures. This calculation program can be advantageously applied in the clinical management of blowout fractures of the orbit.

Reperfusion of autotransplanted teeth--comparison of clinical measurements by means of dental magnetic resonance imaging

OBJECTIVE

Dental magnetic resonance imaging (dMRI) with administration of contrast material is one method of assessing pulpal perfusion. The purpose of this study was to evaluate the level of contrast enhancement displayed by means of dMRI after transplantation of teeth and to compare these findings with the results of tooth mobility, pocket depth, cold, and electrical tests.

STUDY DESIGN

Twenty-three teeth with either complete root formation or incomplete root formation (IRF) were investigated by using dMRI and were clinically examined at intervals of 2, 4, 8, and 12 weeks, as well as 6 months and 12 months after transplantation.

RESULTS

An analysis of the enhancement in the dental images revealed a significant difference between teeth with IRF and teeth with complete root formation. In addition, the time to occurrence of a positive reaction to the cold test was significantly longer for teeth with IRF.

CONCLUSIONS

The findings of this study indicate that transplanted IRF teeth are associated with reperfusion seen by means of dMRI as well as with delayed occurrence of a positive cold test.

Molecular and pharmacological properties of insect biogenic amine receptors: lessons from Drosophila melanogaster and Apis mellifera

In the central nervous system (CNS) of both vertebrates and invertebrates, biogenic amines are important neuroactive molecules. Physiologically, they can act as neurotransmitters, neuromodulators, or neurohormones. Biogenic amines control and regulate various vital functions including circadian rhythms, endocrine secretion, cardiovascular control, emotions, as well as learning and memory. In insects, amines like dopamine, tyramine, octopamine, serotonin, and histamine exert their effects by binding to specific membrane proteins that primarily belong to the superfamily of G protein-coupled receptors. Especially in Drosophila melanogaster and Apis mellifera considerable progress has been achieved during the last few years towards the understanding of the functional role of these receptors and their intracellular signaling systems. In this review, the present knowledge on the biochemical, molecular, and pharmacological properties of biogenic amine receptors from Drosophila and Apis will be summarized. Arch.

Midfacial degloving: an alternative approach for traumatic corrections in the midface

Midfacial degloving was used as an approach in 14 patients to correct post-traumatic deformities in the midface. In eight patients, deformities in the naso-orbito-ethmoid region were corrected by orbitonasal osteotomy, telecanthus correction, orbital grafting and nasal augmentation procedures. Zygomatic osteotomies were performed in five patients with orbitozygomatic deformity. In one patient, a midface fracture (Le Fort II/III) was reconstructed after midfacial degloving. By combination of transoral vestibular, intranasal and preseptal transconjunctival incisions a complete degloving of the midface up to the nasofrontal angle and the zygoma prominence was possible. All osteotomies could be completed after midfacial degloving. Additional coronal incisions were not required. Orbitonasal osteotomies for nasal lengthening as well as fixation of the medial canthal ligament by a miniplate could be performed under direct vision. There were no postoperative complications such as stenosis of the nasal aperture or disturbances of the mimic musculature. Midfacial degloving offers good exposure, specially of the central part of the midface, without leaving an external scar. It is useful for reconstructive procedures in patients after midface trauma.

A cGMP-gated channel subunit in Limulus photoreceptors

The phototransduction cascade in invertebrate photoreceptors has not been fully elucidated. It has been proposed that in Limulus ventral photoreceptor cGMP is the intracellular second messenger that directly controls the gating of the light-dependent channels (Johnson et al., 1986: Bacigalupo et al., 1991). Recently, a putative cGMP-gated channel cDNA, Lcng1, has been cloned from Limulus and shown to be expressed in the brain and the ventral eye (Chen et al., 1999). In this study, we sought to more specifically localize the LCNG1 transcript and protein. In situ hybridization was used to determine whether the gene is expressed in glia or photoreceptor cells in the ventral eye. The results clearly demonstrated that Lcngl mRNA is transcribed in the ventral photoreceptors. On Western blots probed with a polyclonal antibody raised against the C-terminus of LCNGI, a 100-kDa band and an 80-kDa band was labeled in the membrane protein preparations from brain and ventral eye, respectively. The labeling of these bands was blocked by preabsorption of the antibody with the antigen, indicating the labeling specificity. Immunocytochemistry and confocal microscopy were applied to investigate the subcellular localization of this antigen. Immunolabeling was highly localized in the transducing lobes of ventral eye photoreceptors and lateral eye photoreceptors. In both cases, the labeling was associated with membrane regions specialized for phototransduction, but the exact pattern appeared to be somewhat different in the two eyes. Preabsorption of the antiserum with antigen abolished the labeling, confirming specificity. The results lend support to the hypothesis that a cGMP-gated channel is directly involved in the phototransduction process.

Nurses' experiences of restructuring in three Ontario hospitals

PURPOSE

To describe the effects of restructuring, particularly redeployment, on nurses' personal and work lives, and to compare the utility of "survivor syndrome" and empowerment as alternative concepts for understanding these effects and planning change.

METHODS

Twenty-six focus groups or interviews were held with 59 nurses working in three hospitals in Ontario, Canada.

FINDINGS

Participants described how restructuring strategies had affected them as individuals, as members of nursing teams, and as employees. In each of these aspects of their work lives, relationships became less integrated, their work activities became less controllable, and the changes compromised their ability to deliver effective care.

CONCLUSIONS

Restructuring intensifies structural weaknesses in professions, such as nursing, whose members are primarily employed by bureaucracies. Nurses may not find survivor syndrome a useful model to explain their low morale following restructuring because it identifies nurses as "patients" in need of therapy. An empowerment model that takes into account nurses' concerns about uncertainty and integration may be more fruitful for devising strategies to enhance their ability to practice effectively in hospital settings.

3D contrast-enhanced MR angiography of the run-off vessels: value of image subtraction

The diagnostic gain associated with image subtractions was assessed regarding contrast-enhanced 3D magnetic resonance angiography (MRA) image sets of the pelvic and lower extremity arteries. The MRA strategy combined a dedicated vascular coil with a single injection, two-station protocol. Voxel-by-voxel signal intensity subtraction was performed on MRA image sets obtained before and during dynamic infusion of a para-magnetic contrast agent. Non-subtracted and subtracted MRA image sets were assessed for the presence of occlusive (four grades) disease, using DSA as the standard of reference. In addition, SNR and CNR were recorded for each vascular segment on both the non-subtracted and subtracted images. While CNR values of subtracted images exceeded those of non-subtracted images (P < 0.05), there was no difference in diagnostic performance. For the detection of hemodynamically significant disease, non-subtracted and subtracted MRA provided overall sensitivity and specificity of 90.2%/90.3% and 95.1%/95.6%, respectively. Concordance between non-subtracted and subtracted MRA was excellent (Kappa = 0.86).

Use of the preseptal transconjunctival approach in orbit reconstruction surgery

PURPOSE

This report evaluated the advantages of the preseptal transconjunctival approach in reconstruction of the orbit.

PATIENTS AND METHODS

Ninety-nine preseptal incisions were used in 80 patients for different indications (blowout fracture, complex zygoma fracture, enophthalmos correction, midface hypoplasia, secondary incision). All operative procedures were performed without an additional lateral canthotomy. The infraorbital rim was stabilized with miniplates or microplates.

RESULTS

There was no ectropion or entropion in any patients. Complications included 1 laceration of the tarsal plate and 1 temporary entropion after a primary subciliary incision. The overall complication rate was 2%.

CONCLUSIONS

The preseptal transconjunctival incision without lateral canthotomy provides good exposure of the orbital floor and the caudal parts of the lateral and medial wall. This approach is preferable to a retroseptal approach in reconstructive orbital surgery because of minimal disturbance of the intraorbital connective tissue framework. The anatomic optimal dissection line also results in a lower complication rate.