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PubMed2004

[Titanium modular revision prosthesis stem in revision hip prosthesis].

In revision arthroplasty of the hip, femoral defects and fractures must be bridged by a long stem. The implant has to be adapted exactly to the diameter of the cortical tube and has to be placed distally beyond the pathologic area. The titanium modular revision prosthesis (MRP) stem consists of the titanium alloy Ti6Al7Nb and is offered in various diameters, lengths, and special devices, which allows individual and load-stable reconstruction. The aim of the current study is to scrutinize first clinical and radiological results of the titanium MRP revision stem in revision arthroplasty of the hip. We report the midterm results of 130 non-cemented revision arthroplasties of the hip using the titanium MRP revision stem with a mean follow-up of 2.9 years (minimum: 1 year, maximum: 8 years), including 56 men and 74 women. The indication for revision arthroplasty was aseptic loosening of the cup and stem in 94 cases, loosening of the stem in 17 cases, reimplantation in a Girdlestone situation in 11, and periprosthetic fractures in 8 cases. The Harris hip score improved from 50.9+/-24.6 preoperatively to 88.5+/-11.5 postoperatively. The score according to Merle d'Aubigné improved from 9.8+/-4.0 preoperatively to 15.2+/-2.8 postoperatively. We found three recurrent dislocations, two lesions of the sciatic nerve, three cases of persisting deep infection, two periprosthetic fractures, and one case of subsidence of the stem of 2 cm required revision of the MRP stem. Atrophy of the proximal femur was visible in all cases with a stem diameter >17 mm (39/130). Stable primary fixation was achieved in 129 of 130 cases. The titanium MRP revision has proved to be a very reliable implant in cementless revision arthroplasty of the hip.

Aged↗
PubMed2001

Modular organization of the monkey presubiculum.

There have been previous reports of somatostatin- and acetylcholinesterase (AChE)-positive patches in the superficial layers of the presubiculum in monkeys. In this study, we show additional instances of patches in the presubiculum, as demonstrated by cytochrome oxidase (CO), by myelin and Nissl stains, and by the calcium-binding proteins calbindin (CB), calretinin (CR), and parvalbumin (PV). Markers are differentially expressed along the lateral and longitudinal axes. Comparisons of adjacent sections reacted for different markers suggest that the CB+ and CR+ patches, and CO+ and AChE+ patches generally correspond, but not the CB+ and CO+ patches. In cross section, patches are about 100-300 microm in width. Sections cut tangentially through the superficial layers indicate that the pattern of CO and AChE labeling is in fact patchlike in layer I, but that the apparent patches in layer II (CB and CR) form a reticular or lattice-like network. As patches are restricted to the presubiculum, these labeling patterns provide a convenient marker for the boundary between the presubiculum and the adjoining posteroventral retrosplenial cortex. More work is necessary to determine how this modularity may relate to the functional organization of the presubiculum.

Acetylcholinesterase↗
PubMed2006

Interventional radiology: a modular approach.

The authors offer a modular approach to the development of new procedures in the field of pediatric interventional radiology as a conceptual model and a springboard for further discussion.

Humans↗
PubMed1996

Do the non-catalytic polysaccharide-binding domains and linker regions enhance the biobleaching properties of modular xylanases?

Xylanase A (XylA) from Pseudomonas fluorescens subsp. cellulosa consists of an N-terminal non-catalytic cellulose-binding domain joined to a functionally independent C-terminal catalytic domain by a sequence rich in serine residues. Xylanase D (XylD) from Cellulomonas fimi also exhibits a modular structure comprising an N-terminal catalytic domain linked to an internal non-catalytic xylan-binding domain and a C-terminal cellulose-binding domain. To determine the importance of the non-catalytic polysaccharide-binding domains and linker sequences of XylA and XylD in relation to their capacity to hydrolyse pulp xylan and enhance bleachability, purified full-length and modified derivatives of both enzymes were incubated with a hardwood kraft pulp. Deletion of the cellulose-binding domain or linker region from XylA decreased the activity of the enzyme against pulp xylan, but had no significant effect on the capacity of the enzyme to facilitate delignification and reduce pulp kappa number. While full-length and truncated forms of XylD, lacking either the cellulose-binding or the cellulose- and xylan-binding domains, were equally effective in hydrolysing pulp xylan, enzyme derivatives containing a polysaccharide-binding domain were marginally more efficient in reducing pulp kappa number. The reduction in kappa number elicited by full-length and isolated catalytic domains of XylA and XylD was reflected in an increase in the brightness of paper handsheets derived from pretreated pulps. Thus, the polysaccharide-binding domains of XylA and XylD did not appear to confer any advantage in terms of the ability of the enzymes to improve pulp bleachability. However, XylA and XylD, which belong to different glycosyl hydrolase families, differed in their ability to hydrolyse pulp xylan and facilitate the delignification of kraft pulp.

Actinomycetales↗
PubMed2002

Modular megaprosthesis for proximal femoral tumors.

Fifteen patients with proximal femoral tumors had resection and limb salvage with an uncemented Kotz (HMRS) megaprosthesis. There were five osteosarcomas, four chondrosarcomas, one hemangioendothelioma, three fibrosarcomas, and two Ewing's sarcomas. The mean follow-up was 6.7 (range 3-10) years. Two patients died of causes not related to the prosthesis. The postoperative Musculoskeletal Tumor Society score (MSTS) score was 19 (range 12-26) for the remaining 13 patients. There were one aseptic loosening, two infections, and one local recurrence. The most frequent complication was hip dislocation at 20%. Reconstruction of proximal femoral tumors with a modular megaprosthesis is a good procedure, but hip instability remains a major problem.

Adolescent↗
PubMed2004

Modular total shoulder system with short stem. A prospective clinical and radiological analysis.

Between 1994 and 2001, a short-stemmed modular shoulder prosthesis was inserted in 62 shoulders in patients with rheumatoid arthritis (RA) or osteoarthrosis (OA). We reviewed 53 patients with 60 shoulders (45 RA/15 OA) with at least 24 months follow-up. In 22 shoulders, we used a total shoulder prosthesis including a glenoid polyethylene component, whereas 38 shoulders only had a humeral component. In six shoulders, the humeral component was cemented. The average follow-up was 47 (24-99) months. There were no intraoperative complications but one wound infection and one patient with proximal migration of the humeral component. Hospital for Special Surgery Score increased from 44(19-72) to 63 (21-93) points and Shoulder Function Assessment score (SFA) from 24 (12-46) to 42 (11-66)points. The VAS score for pain at rest improved from 4.3 to 1.9. Nonprogressive radiolucent lines were seen adjacent to nine glenoid and one humeral components. Fifty-six patients were satisfied with the result.

Aged↗
PubMed2000

A modular femoral implant for uncemented stem revision in THR.

We present the early results of 142 uncemented femoral stem revisions using the modular MRP-Titan system. There were 70 cases with marked preoperative femoral bone defects (Paprosky type 2C and type 3); and bone grafts were used in 31 cases. At a mean follow-up of 2.3 years five cases were re-revised due to dislocation and two due to aseptic loosening. The mean Harris hip score improved from 37.4 preoperatively to 92.4. In 122 cases progressive bone regeneration on X-ray was seen; and no further osteolysis was observed.

Adult↗
PubMed2000

Limb salvage for proximal tibial tumours using a modular prosthesis.

We report early results after the resection of proximal tibial tumours followed by reconstruction using a modular prosthesis. The indication for wide resection was a malignant tumour in 13 patients, and a neglected giant cell tumour in 2. There were no mechanical failures during an average follow-up of 3.5 years. However, there were 5 peroneal nerve palsies, 1 complete sciatic nerve palsy, 1 vascular injury leading to an above knee amputation, and 2 deep prosthetic infections. There were 2 superficial skin necroses and 1 fracture proximal to the femoral prosthetic component. The mean post-operative Musculo-Skeletal Tumour Society (MSTS) score in 12 patients who still had their prosthesis in situ was 18.3 out of a possible total of 30 (range: 10-28). Limb salvage surgery in the proximal tibia has a high early complication rate even with the use of modern implants and improved techniques.

Adolescent↗
PubMed2001

Modular megaprosthesis for distal femoral tumors.

We treated 48 patients with distal femoral tumors by resection and limb salvage with an uncemented megaprosthesis (Howmedica Modular Replacement System). Diagnoses included: 32 osteosarcomas, five chondrosarcomas, six giant cell tumors of the bone, three fibrosarcomas, and two Ewing's sarcomas. The mean follow-up was 5.6 years (2-10 years). The overall complication rate was 39%. Seven patients died of their disease, but none from complications related to the surgery. Five patients were revised to arthrodesis, and one required amputation because of complications. The mean postoperative Musculoskeletal Tumor Society score (MSTS) score was 21 (6-28) for the remaining 35 patients. The most frequent complications were infection (14.6%) and aseptic loosening (4.8%). Ten-year survival of the prosthesis was 65%.

Adolescent↗
PubMed2003

The non-catalytic amino acid Asp446 is essential for enzyme activity of the modular endocellulase Cel9 from Myxobacter sp. AL-1.

The modular endocellulase Cel9 of the bicistronic operon cel9-cel48 of Myxobacter sp. AL-1 shares not only amino acid sequence similarity but also biochemical properties similar to those of Thermobifida fusca endo/exocellulase E4. Amino acid alignments of a T. fusca E4 cellulase subfamily of family 9 cellulases revealed that Asp(446) of Myxobacter sp. AL-1 Cel9, a putatively noncatalytic residue, is highly conserved in one of the catalytic domains of this subfamily. Directed mutagenesis of residue aspartate (Asp(446)) to alanine generated a Cel9 mutant that lost more than 99% of its activity, suggesting that Asp(446) plays an essential structural role in Cel9 during cellulose degradation. Owing to its high degree of conservation and essential role, we propose that Asp(446) of Myxobacter sp. AL-1 Cel9 is a good landmark that distinguishes members of the E4 subfamily of family 9 cellulases.

Amino Acid Sequence↗
PubMed1998

[Modular memory training for elderly adults: concept and evaluation].

We present a modular concept of a cognitive training relevant to the demands of everyday life of community dwelling older adults. The concept has three major advantages. First, it takes into account the current performance levels and needs of the trainees. Second, the training is economical in aiming at selecting the most effective training elements. Third, the concept allows the evaluation of single elements of the training. The application of this concept points at the importance of training content being relevant to trainees' everyday lives. Results indicate that training effectiveness depends on the starting level of performance and the cognitive domain being trained. Overall, the results demonstrate the possibility to maximize training gains of older adults by designing adequate trainings for well-defined subgroups of normal older adults.

Activities of Daily Living↗
PubMed2000

Quality of life in psychiatry: a systematic contribution to construct validation and the development of the integrative assessment tool "modular system for quality of life".

The aim of the present study is to contribute to an ongoing validation process of the Quality of Life (QoL) construct in the clinical field by investigating its internal structure. Eight (inter)nationally validated questionnaires have been analyzed by an integrative approach in a multicenter study. Data has been collected in a mentally healthy (n = 479), a depressed (n = 171) and a schizophrenic (n = 139) sample. Apart from conventional psychometric criteria a similarity structure analysis (SSA) within a facet analytic methodology has been applied. A dimensional structure of the resulting integrative questionnaire "Modular System for Quality of Life" (MSQoL) could be generated that consists of one "G-factor" (life in general) and six specific dimensions (physical health, vitality, psychosocial relationships, material resources, affect, leisure time). This basic structure represents a core module measured by 47 items which is sufficiently valid for all three samples. The empirical structures of healthy, depressed and schizophrenic samples fulfill the first law of attitude and share a common variance of 95%. In addition, there are four specific modules (demography, family, partnership, profession). No specific modules could be identified for the psychopathological subgroups. The conclusion can be drawn that QoL is construed very similar by all three investigated populations which is the base for searching for quantitative differences and profiles. The MSQoL integrates the non-redundant components of eight QoL-instruments, is psychometrically able to assess the basic structure and can be completed within a cumulative research design by items specific for a particular setting.

Adolescent↗
PubMed2006

Secreted modular calcium-binding protein-1 localization during mouse embryogenesis.

BM-40 is an extracellular matrix-associated protein and is characterized by an extracellular calcium-binding domain as well as a follistatin-like domain. Secreted modular calcium-binding protein-1 (SMOC-1) is a new member of the BM-40 family. It consists of two thyroglobulin-like domains, a follistatin-like domain and a new domain without known homologues and is expressed ubiquitously in many adult murine tissues. Immunofluorescence studies, as well as immunogold electron microscopy, have confirmed the localization of SMOC-1 in or around basement membranes of adult murine skin, blood vessels, brain, kidney, skeletal muscle, and the zona pellucida surrounding the oocyte. In the present work, light microscopic immunohistochemistry has revealed that SMOC-1 is localized in the early mouse embryo day 7 throughout the entire endodermal basement membrane zone of the embryo proper. SMOC-1 mRNA is synthesized, even in early stages of mouse development, by mesenchymal as well as epithelial cells deriving from all three germ layers. In embryonic stage day 12, and fetal stages day 14, 16, and 18, the protein is present in the basement membrane zones of brain, blood vessels, skin, skeletal muscle, lung, heart, liver, pancreas, intestine, and kidney. This broad and organ-specific distribution suggests multifunctional roles of SMOC-1 during mouse embryogenesis.

Animals↗
PubMed1999

Emergence of symmetric, modular, and reciprocal connections in recurrent networks with Hebbian learning.

While learning and development are well characterized in feedforward networks, these features are more difficult to analyze in recurrent networks due to the increased complexity of dual dynamics - the rapid dynamics arising from activation states and the slow dynamics arising from learning or developmental plasticity. We present analytical and numerical results that consider dual dynamics in a recurrent network undergoing Hebbian learning with either constant weight decay or weight normalization. Starting from initially random connections, the recurrent network develops symmetric or near-symmetric connections through Hebbian learning. Reciprocity and modularity arise naturally through correlations in the activation states. Additionally, weight normalization may be better than constant weight decay for the development of multiple attractor states that allow a diverse representation of the inputs. These results suggest a natural mechanism by which synaptic plasticity in recurrent networks such as cortical and brainstem premotor circuits could enhance neural computation and the generation of motor programs.

Animals↗
PubMed2006

Validation of the Japanese version of the Rome II modular questionnaire and irritable bowel syndrome severity index.

BACKGROUND: Instruments for measuring the presence and severity of specific irritable bowel syndrome (IBS) symptoms, comparable to those used in Western countries, have been lacking in Japan. The aim of this study was to develop, validate, and confirm the reliability of the Japanese version of the Rome II modular questionnaire for IBS (RIIMQ-J) and the IBS severity index (IBSSI-J). METHODS: Forty-nine patients in the university hospital with chronic or recurrent abdominal pain and discomfort and/or altered bowel habits were enrolled. With Rome II criteria, 27 patients were diagnosed as having IBS, and the other 22 patients were evaluated as having other functional bowel disorders (FBDs). The English versions of RIIMQ and IBSSI were translated into Japanese. After back-translation and approval of the questionnaire, subjects completed both questionnaires twice within 14 days. RESULTS: Cronbach's alpha of the RIIMQ-J was high (0.72). The sensitivity of RIIMQ-J for the diagnosis of IBS was also high (89%). The specificity of RIIMQ-J for denial of IBS among patients with other FBD was satisfactory (73%). The IBSSI-J showed high internal consistency (0.69) and reproducibility (intraclass correlation coefficient, 0.86, P < 0.001). CONCLUSIONS: The RIIMQ-J and IBSSI-J are valid, reliable, and appropriate instruments for detecting and assessing the severity of IBS status in Japanese patients.

Diagnosis, Differential↗
PubMed1999

Artificial disc replacement with the modular type SB Charité III: 2-year results in 50 prospectively studied patients.

The Modular Type SB Charite disc prosthesis has been developed as a device for artificial disc replacement (ADR) in patients with symptomatic discopathies. Here, we report on our first series of 50 (out of 350) patients, who had a satisfactory clinical result in 70% of cases (2 years' follow-up). Subgroup analysis revealed that patients with an isolated discopathy without previous spinal operations or other pathology at the same or other spinal level benefitted more from the surgery. However, this technique was associated with some problems: a 13% rate of permanent side-effects and/or complications was observed caused by the anterior approach. Four percent were related to poor implantation technique. There were no problems related to the material of the prosthesis. Twelve patients needed re-operation, but this was beneficial in only three of them. In one patient we had to convert to an interbody fusion. We conclude that in patients with severe isolated symptomatic discopathies that are resistant to conservative treatment, a mobile disc prosthesis is worth considering as a real alternative to a spondylodesis. However, accurate patient selection is imperative. With these criteria we were encouraged by our results to continue the implantation of this artificial disc.

Adult↗
PubMed2000

Modular organization and identification of a mononuclear iron-binding site within the NifU protein.

The NifS and NifU nitrogen fixation-specific gene products are required for the full activation of both the Fe-protein and MoFe-protein of nitrogenase from Azotobacter vinelandii. Because the two nitrogenase component proteins both require the assembly of [Fe-S]-containing clusters for their activation, it has been suggested that NifS and NifU could have complementary functions in the mobilization of sulfur and iron necessary for nitrogenase-specific [Fe-S] cluster assembly. The NifS protein has been shown to have cysteine desulfurase activity and can be used to supply sulfide for the in vitro catalytic formation of [Fe-S] clusters. The NifU protein was previously purified and shown to be a homodimer with a [2Fe-2S] cluster in each subunit. In the present work, primary sequence comparisons, amino acid substitution experiments, and optical and resonance Raman spectroscopic characterization of recombinantly produced NifU and NifU fragments are used to show that NifU has a modular structure. One module is contained in approximately the N-terminal third of NifU and is shown to provide a labile rubredoxin-like ferric-binding site. Cysteine residues Cys35, Cys62, and Cys106 are necessary for binding iron in the rubredoxin-like mode and visible extinction coefficients indicate that up to one ferric ion can be bound per NifU monomer. The second module is contained in approximately the C-terminal half of NifU and provides the [2Fe-2S] cluster-binding site. Cysteine residues Cys137, Cys139, Cys172, and Cys175 provide ligands to the [2Fe-2S] cluster. The cysteines involved in ligating the mononuclear Fe in the rubredoxin-like site and those that provide the [2Fe-2S] cluster ligands are all required for the full physiological function of NifU. The only two other cysteines contained within NifU, Cys272 and Cys275, are not necessary for iron binding at either site, nor are they required for the full physiological function of NifU. The results provide the basis for a model where iron bound in labile rubredoxin-like sites within NifU is used for [Fe-S] cluster formation. The [2Fe-2S] clusters contained within NifU are proposed to have a redox function involving the release of Fe from bacterioferritin and/or the release of Fe or an [Fe-S] cluster precursor from the rubredoxin-like binding site.

Amino Acid Sequence↗
PubMed2006

Comparative characterization of deletion derivatives of the modular xylanase XynA of Thermotoga maritima.

The modular Xylanase XynA from Thermotoga maritima consists of five domains (A1-A2-B-C1-C2). Two similar N-terminal domains (A1-A2-) are family 22 carbohydrate-binding modules (CBMs), followed by the catalytic domain (-B-) belonging to glycoside hydrolase family 10, and the C-terminal domains (-C1-C2), which are members of family 9 of CBMs. The gradual deletion of the non-catalytic domains resulted in deletion derivatives (XynADeltaC; XynADeltaA1C and XynADeltaNC) with increased maximum activities (V (max)) at 75 degrees C, pH 6.2. Furthermore, these deletions led to a shift of the optimal NaCl concentration for xylan hydrolysis from 0.25 (XynA) to 0.5 M (XynADeltaNC). In the presence of the family 22 CBMs, the catalytic domain retained more activity in the acidic range of the pH spectrum than without these domains. In addition to the deletion derivatives of XynA, the N-terminal domains A1 and A2 were produced recombinantly, purified, and investigated in binding studies. For soluble xylan preparations, linear beta-1,4-glucans and mixed-linkage beta-1,3-1,4-glucans, only the A2 domain mediated binding, not the A1 domain, in accordance with previous observations. The XynA deletion enzymes lacking the C domains displayed low affinity also to hydroxyethylcellulose and carboxymethylcellulose. With insoluble oat spelt xylan and birchwood xylan as the binding substrates, the highest affinity was observed with XynADeltaC and the lowest affinity with XynADeltaNC. Although the domain A1 did not bind to soluble xylan preparations, the insoluble oat spelt xylan-binding data suggest that this domain does play a role in substrate binding in that it improves the binding to insoluble xylans.

Base Sequence↗