bluuebunny/crossref_metadata_2025 huggingface dataset:
The COSTAR wheelchair study: a two-centre pilot study of self-propulsion in a wheelchair in early stroke rehabilitation
Authors: Barrett J A , Watkins C , Plant R , Dickinson H , Clayton L , Sharma A K , Reston A , Gratton J , Fall S , Flynn A , Smith T , Leathley M , Smith S , Barer D H
Published: May 2003

Objective: It is uncertain whether self-propulsion in a wheelchair should be encouraged or discouraged in the early stages of stroke rehabilitation.

Design: A two-centre pilot study to assess the feasibility of performing a multicentre randomized controlled trial on this subject.

Setting: Clatterbridge and Aintree Stroke Rehabilitation Units, Merseyside, UK.

Subjects: Forty early stroke patients (mean age 67 years) in whom it was uncertain whether self-propulsion in a wheelchair should be encouraged were studied.

Intervention: A central randomization service at Newcastle University was used to determine the policy about wheelchair provision and use for each patient. They were allocated to either an ‘encouraged to self-propel’ or a ‘discouraged from self-propulsion group’.

Outcome measures used: Independent outcome assessment was performed by postal questionnaire and telephone interview using the Barthel ADL Scale, Nottingham Extended ADL Scales and the shortened General Health Questionnaire (GHQ-12) at 3 and 12 months. Patient's length of stay and their Ashworth tone score were also measured either at three months or when they were discharged from hospital.

Results: After considerable preparation time it was possible to conduct a trial on self-propulsion in early stroke rehabilitation in the two-pilot centres. No major differences were found between the pilot groups for any of the outcome measures.

Conclusions: A multicentre randomized controlled trial to assess this question is feasible but further work is being conducted before proceeding, to satisfy the concerns expressed to our group regarding the appropriateness of the intervention and the outcome measures. Address for correspondence: JA Barrett, Clatterbridge Hospital, Wirral, Merseyside CH69 4JY, UK. e-mail: jabarrett@clatterbridgesru.freeserve.co.uk
An exploration of the effects of weighted garments on balance and gait of stroke patients with residual disability
Authors: Pomeroy V M , Evans B , Falconer M , Jones D , Hill E , Giakas G
Published: May 2003

Objective: To explore the effects of weighted garments on the balance and gait of stroke patients.

Design: A pilot randomized controlled study with blinded measurement.

Setting: Weighted garments were worn by patients living in the community and measurement was made in a hospital-based gait laboratory.

Subjects: Twenty-four adults who were at least six months post stroke and were able to walk 10 metres with or without assistance or a walking aid.

Intervention: The six-week treatment-phase subjects were given a set of weighted garments which they were shown how to apply and instructed to wear on their paretic side. Subjects randomly allocated to the six-week control phase were not given any weighted garments.

Main outcome measures: Balance was measured with the Berg Balance Scale. Gait was measured using GaitMat II, an instrumented walkway. Gait parameters of interest were velocity and symmetry of: step length; single support time; double support time; and support base width. Measures were made at baseline before randomization (baseline) and at the end of the six weeks of intervention (outcome).

Results: No statistically significant differences were found between the treatment and control groups at outcome for balance (Mann–Whitney U-test; p = 0.74), gait velocity (p = 0.68) or symmetry of gait parameters (p = 0.33 to p = 0.75).

Conclusions: We found no evidence to support the clinical use of these weighted garments for stroke survivors.
Factors influencing rate of Barthel Index change in hospital following stroke
Authors: McNaughton Harry , Weatherall Mark , Taylor William , Mcpherson Kathryn
Published: May 2003

Background and purpose:Randomized controlled trials of specific interventions in stroke rehabilitation are few. In using this study design to compare different rehabilitation interventions or different intensity of those interventions, measuring disability status at a fixed time point is one outcome option. In order for this approach to be valid, factors that might independently affect the speed of disability change have to be matched at baseline. We sought to investigate the impact of different factors on rate of disability change following stroke.

Methods: A prospective hospital-based study of consecutive patients admitted to each of three general hospitals in Wellington, New Zealand with acute stroke. Patients were assessed using the Barthel Index (BI, scored 0–20) within a few days of stroke and fortnightly until hospital discharge. Strokes were classified using the Oxfordshire Community Stroke Project classification.

Main outcome measure: Barthel Index rate of change (BRC) computed from the difference between the first and last hospital BI scores divided by the time in weeks between these assessments.

Results: Of 104 subjects with two or more disability assessments in hospital, BRC was a mean 1.26 units per week (95% confidence interval (CI) 0.97, 1.56). The only factors significantly associated with BRC on univariate analysis were stroke type, pre-stroke Modified Rankin Scale (MRS) and pre-stroke London Handicap Score. In a general linear model analysis of covariance, stroke type (p = 0.015) and pre-stroke MRS (p < 0.001) remained significant. The mean BRC for lacunar infarcts (1.76 units per week, 95% CI 1.22, 2.30) was over three times that of total anterior circulation infarcts (0.48 units per week, 95% CI 0.20, 0.76).

Conclusions: Future randomized controlled trials of rehabilitation interventions for stroke in hospitalized patients need to allow for pre-stroke level of dependence and stroke type in the study design, either excluding particular patients or ensuring even randomization of these key variables if speed of disability change is to be a valid outcome variable.
Association between amputation, arthritis and osteopenia in British male war veterans with major lower limb amputations
Authors: Kulkarni Jai , Adams Judith , Thomas Elaine , Silman Alan
Published: May 2003

Objectives: To investigate the association between amputation, osteoarthritis and osteopenia in male war veterans with major lower limb amputations. Specific questions were to determine whether lower limb amputees following trauma are at subsequent risk of developing osteoarthritis (OA) and osteoporosis of the hip on both the amputated and nonamputated sides.

Design: Retrospective cohort study in British Male Second World War veterans with major unilateral lower limb amputations.

Subjects: Seventy-five male Second World War veterans with major lower limb amputations known to be alive were invited to participate from a subregional rehabilitation centre. After exclusions, 44 agreed to attend for examination and radiological screening.

Methods: The presence of hip OA was determined from a single anterior posterior pelvic X-ray using two approaches: minimum joint space and the Kellgren and Lawrence (K&L) scoring system. Bone mineral density (BMD) was measured by a dual energy X-ray absorptiometry (DXA) scan and prosthetic rehabilitation outcome measures were recorded.

Results: Twenty-seven (61%) hips on the amputated side and 10 (23%) on the nonamputated side were positive for OA (based on Kellgren and Lawrence grade of >2). Using a minimum joint space threshold of below 2.5 mm, 24 (55%) hips on the amputation side and 8 (18%) on the nonamputated side were also positive for OA. There was a threefold increased risk of OA for those with above-knee compared to a below-knee amputation. By contrast, from published general population surveys only 4 (11%) cases of hip OA would have been expected on both the amputated and nonamputated hips.

There was a significant decrease in femoral neck BMD in the amputated side ( p <0.0001) and significantly lower BMD in above-knee amputees than in below-knee amputees ( p = 0.0027) as compared to normal age-and sexmatched population.

Conclusion: Male war veterans with unilateral major lower limb amputations develop significantly more osteoarthritis of the hip than expected on both ipsi-and contralateral sides. Amputation was also associated with loss of bone density. Above-knee amputees develop significantly more hip osteoarthritis and osteopenia of greater severity in the amputated side than below-knee amputees.
A longitudinal physical profile assessment of skeletal muscle manifestations in myotonic dystrophy
Authors: Nitz J C , Burns Y R , Jackson R V
Published: May 2003

Objectives: To develop an assessment that describes the skeletal muscle manifestations in myotonic dystrophy subjects and then use it to quantify the presentation of skeletal muscle disability and to show change over time.

Design: A quantified skeletal muscle assessment was developed and applied three times over a two-year period at intervals around 12 months. Thirty-six subjects with myotonic dystrophy and 20 subjects without neuromuscular disability were evaluated. The assessment comprised manual muscle testing of five pairs of muscles, measuring neck flexor strength with a strain gauge, respiratory function tests, power and lateral pinch grip strength, all tests of impairment. Assessment of the ability to move from sitting to standing and fasten buttons tested disability.

Results: Results from subjects with myotonic dystrophy were compared to the normal data. The subjects with myotonic dystrophy were significantly weaker in proximal upper limb muscles, quadriceps, tibialis anterior muscles and neck flexor muscles as well as power and lateral pinch grips. There was also significant reduction in forced expiratory volume at one second (FEV1) and forced vital capacity (FVC). Significant disability was seen in the myotonics in moving from sitting to standing and in fastening buttons. Over the two-year study period proximal upper limb and lower limb muscle strength, FVC and sit-to-stand ability declined significantly. Power grip declined but lateral pinch grip and FEV1 improved significantly. Button fastening ability improved significantly.

Conclusion: The test developed was shown to be reliable and sensitive to the change in skeletal muscle manifestations in subjects with myotonic dystrophy who were shown to be significantly weaker than normal subjects.
Study of the relationship between premorbid urinary incontinence and stroke functional outcome
Authors: Jawad S H , Ward A B , Jones P
Published: May 2003

Objective: To examine functional outcome in stroke patients with premorbid incontinence of urine.

Method: Comparative study in stroke patients between premorbidly incontinent and continent groups. Both groups were subjected to structured interview, clinical examination and functional assessment at one week post stroke. Functional assessment was repeated six months later.

Subjects: Eighty-six patients with first-time stroke younger than 80 years of age admitted to hospital, were divided into two groups according to their continence status.

Outcome measure: The 20-point Barthel Index.

Setting: Medical wards at North Staffordshire Teaching Hospitals.

Results: Of 86 stroke patients (46 continent and 40 premorbidly incontinent), 19 died before six-month assessment, of whom 15 (79%) were premorbidly incontinent. Premorbid incontinence was the most significant variable predicting poor functional outcome (Barthel Index score <15) at six months, with a sensitivity of 82.6% and specificity of 86.4% and with age-corrected p-value of <0.001.

Conclusions: This study shows a significant relationship between premorbid incontinence and functional outcome at six months. However, other causes that could have contributed to the premorbid incontinence were not excluded. This point needs to be considered in future studies, which should also examine whether premorbid incontinence per se reflects an underlying predisposition for stroke.
Should Adolescents With Acute Lymphoblastic Leukemia Be Treated as Old Children or Young Adults? Comparison of the French FRALLE-93 and LALA-94 Trials
Authors: Boissel Nicolas , Auclerc Marie-Françoise , Lhéritier Véronique , Perel Yves , Thomas Xavier , Leblanc Thierry , Rousselot Philippe , Cayuela Jean-Michel , Gabert Jean , Fegueux Nathalie , Piguet Christophe , Huguet-Rigal Françoise , Berthou Christian , Boiron Jean-Michel , Pautas Cécile , Michel Gérard , Fière Denis , Leverger Guy , Dombret Hervé , Baruchel André
Published: May 2003

Purpose: To compare pediatric and adult therapeutic practices in the treatment of acute lymphoblastic leukemia (ALL) in adolescents.

Patients and Methods: From June 1993 to September 1994, 77 and 100 adolescents (15 to 20 years of age) were enrolled in the pediatric FRALLE-93 and adult LALA-94 protocols, respectively. Among the different prognostic factors, we retrospectively analyzed the effect of the trial on achieving complete remission (CR) and event-free survival (EFS).

Results: Patients were younger in the FRALLE-93 than in the LALA-94 protocol (median age, 15.9 v 17.9 years, respectively), but other characteristics were similar, including median WBC count (18 × 109 cells/L v 16 × 109 cells/L), B/T-lineage (54 of 23 v 72 of 28 patients), CD10-negative ALL (13% v 15%), and poor-risk cytogenetics (t(9;22), t(4;11), or hypodiploidy less than 45 chromosomes: 6% v 5%). The CR rate depended on WBC count (P = .005) and trial (94% v 83% in FRALLE-93 and LALA-94, respectively; P = .04). Univariate analysis showed that unfavorable prognostic factors for EFS were as follows: the trial (estimated 5-year EFS, 67% v 41% for FRALLE-93 and LALA-94, respectively; P < .0001), an increasing WBC count (P < .0001), poor-risk cytogenetics (P = .005), and T-lineage (P = .01). The trial and WBC count remained significant parameters for EFS in multivariate analysis (P < .0001 and P = .0004). Lineage subgroup analysis showed an advantage for the FRALLE-93 trial for CR achievement (98% v 81%; P = .002) and EFS (P = .0002) in B-lineage ALL and for EFS (P = .05) in T-lineage ALL. Age was not a significant prognostic factor in this population of adolescents.

Conclusion: This study’s findings indicate that adolescents should be included in intensive pediatric protocols and that new trials should be designed, inspired by pediatric protocols, for the treatment of young adults with ALL.
The Cell Surface Form of Colony-Stimulating Factor-1 Is Biologically Active in Bone in Vivo
Authors: Yao Gang-Qing , Wu Jain-Jun , Sun Ben-Hua , Troiano Nancy , Mitnick Mary Ann , Insogna Karl
Published: May 2003

The specific biological function of the cell surface or membrane-bound isoform of colony-stimulating factor-1 (mCSF-1) is not well understood. To help define the role of this isoform in bone, we developed a transgenic mouse in which targeted expression of human mCSF-1 in osteoblasts was achieved under the control of the 2.4-kb rat collagen type I α promoter. Bone density, determined by peripheral quantitative computed tomography, was reduced 7% in mCSF-1 transgenic compared with that in wild-type mice. Histomorphometric analyses indicated that the number of osteoclasts in bone (NOc/BPm, NOc/TAR, OcS/BS) was significantly increased in transgenic mice (1.7- to 1.8-fold; P < 0.05 to P < 0.01) compared with that in wild-type animals. Interestingly, the osteoblast-restricted isoform transgene corrected the osteopetrosis seen in CSF-1-deficient op/op mice. Skeletal growth and bone density in op/op mice expressing mCSF-1 in osteoblasts were similar to those in wild-type mice and were dramatically different from those in the unmanipulated op/op animals. The op/op mice expressing mCSF-1 in bone had normal incisor and molar tooth eruption, whereas the op/op mice evidenced the expected failure of tooth eruption. These findings directly support the conclusion that mCSF-1 is functionally active in bone in vivo and is probably an important local source of CSF-1.
The effects of morphology on the processing of compound words: Evidence from naming, lexical decisions and eye fixations
Authors: Juhasz Barbara J. , Starr Matthew S. , Inhoff Albrecht W. , Placke Lars
Published: May 2003

The use of lexemes during the recognition of spatially unified familiar English compounds was examined in naming, lexical decision and sentence‐reading tasks by manipulating beginning and ending lexeme frequencies while controlling overall compound frequencies. All tasks revealed robust ending lexeme frequency effects, with compound processing being more effective when the ending lexeme was a high‐frequency word. Beginning lexeme frequency effects were more elusive and dependent on task demands. Eye movements, recorded during sentence reading, also indicated that the effects of ending lexemes occurred after the first fixation during compound viewing. Together, the results suggest either that the ending lexeme is used as an access code to locate the meaning of the full compound word or that its meaning is coactive with the meaning of the full compound.
DEC1 (STRA13) protein expression relates to hypoxia‐ inducible factor 1‐alpha and carbonic anhydrase‐9 overexpression in non‐small cell lung cancer
Authors: Giatromanolaki Alexandra , Koukourakis Michael I , Sivridis Efthimios , Turley Helen , Wykoff Charles C , Gatter Kevin C , Harris Adrian L
Published: May 2003

Differentiated embryo‐chondrocyte expressed gene 1 (DEC1) is involved in cell differentiation, proliferation, and apoptosis, and was recently shown to be regulated by hypoxia. The present immunohistochemical study demonstrates extensive nuclear expression of the protein in 38% of a series of 115 non‐small cell lung carcinomas using a polyclonal antibody (Ab) recognizing DEC1 protein. Such expression was directly related to the expression of two hypoxia‐regulated proteins, namely the hypoxia‐inducible factor (HIF) 1α and carbonic anhydrase‐9. Although DEC1 was not related to angiogenesis or to the expression of VEGF and thymidine phosphorylase, a direct association with up‐regulated bFGF receptors was noted. DEC1 was persistently expressed in the nuclei of normal bronchial and alveolar tissue. It is suggested that loss of DEC1 expression is an early event in the development of lung cancer, while DEC1 gene expression occurs in a subset of tumours and parallels the overexpression of other hypoxia‐regulated proteins. Copyright © 2003 John Wiley & Sons, Ltd.
BCL‐2 family proteins in peripheral T‐cell lymphomas: correlation with tumour apoptosis and proliferation
Authors: Rassidakis George Z , Jones Dan , Lai Raymond , Ramalingam Preetha , Sarris Andreas H , McDonnell Timothy J , Jeffrey Medeiros L
Published: May 2003

The present study investigated expression levels of the anti‐apoptotic proteins BCL‐2, BCL‐XL and MCL‐1 and the pro‐apoptotic proteins BAX and BCL‐XS in a series of 112 peripheral T‐cell lymphomas (PTCLs) classified according to the WHO classification. Using immunohistochemical methods and a 10% cut‐off, each protein was detected in a subset of PTCLs: BCL‐2 in 46%, BCL‐XS in 49%, BAX in 57%, BCL‐XL in 57%, and MCL‐1 in 65%. The mean percentage of positive cells for these proteins varied significantly among the PTCL types. Only two types of PTCL, ALK‐positive anaplastic large cell lymphoma (ALCL) and enteropathy‐type T‐cell lymphoma, had a distinctive pattern of expression; all were BCL‐2‐negative and MCL‐1‐positive. The mean percentage of BAX‐positive and BCL‐XS‐positive tumour cells was higher in ALK‐positive ALCL than in ALK‐negative ALCL or other types of PTCL (p = 0.06 and p = 0.01, respectively, Kruskal–Wallis test). MCL‐1 was detected significantly more frequently (p = 0.01, chi‐square test) and at higher levels (p = 0.0001, Kruskal–Wallis test) in ALK‐positive ALCL and ALK‐negative ALCL than in other PTCL types. The apoptotic rate, evaluated by the TUNEL assay, correlated inversely with BCL‐2 expression (p = 0.035). The proliferation index, assessed by the MIB‐1 antibody, correlated with expression levels of MCL‐1 (R = 0.42, p = 0.003), BCL‐2 (R = 0.32, p = 0.027), BAX (R = 0.33, p = 0.014), and BCL‐XL (R = 0.34, p = 0.015) (Spearman rank). In conclusion, BCL‐2 family proteins are expressed by a subset of PTCLs and their levels correlate with some histological types, apoptotic rate, and proliferation index. Expression of these proteins may explain the poor response of many types of PTCL to standard chemotherapy. These proteins may also provide novel targets for experimental therapy. Copyright © 2003 John Wiley & Sons, Ltd.
Laminin α1 chain in human renal cell carcinomas and integrin‐mediated adhesion of renal cell carcinoma cells to human laminin isoforms
Authors: Rissanen Jan , Korhonen Matti , Lehto Veli‐Pekka , Virtanen Ismo
Published: May 2003

In human tissues, the laminin (Ln) α1 chain shows a restricted and developmentally regulated distribution in basement membranes (BMs) of a subset of epithelial tissues, including those of renal proximal convoluted tubules. The present study investigated the distribution of the Ln α1 chain in renal cell carcinomas (RCCs) and oncocytomas as well as in xenografted tumours induced in nude mice with four characterized RCC cell lines. These cell lines were also used in cell adhesion studies with purified laminins. By immunohistochemistry it was found that the Ln α1 chain is widely present in the BMs of RCCs, all of the specimens presenting immunoreactivity. High‐grade RCCs tended to contain more BM‐confined and stromal immunoreactivity than low‐grade tumours, none of the grade 3 (G3) carcinomas being negative and all of the metastatic specimens showing partial or overall BM immunoreactivity. Double immunolabelling experiments showed that in RCC BMs but not in vessel walls, the Ln α1 chain was co‐distributed with Ln α5, β1, and β2 chains, implying the presence of Ln‐1/Ln‐3 and Ln‐10/Ln‐11. In papillary RCCs, the Ln α1 chain co‐localized with Ln‐5. The oncocytomas lacked immunoreactivity for the Ln α1 chain. Xenografted tumours induced in nude mice showed BM‐like deposition of the Ln α1 chain. In cell adhesion studies, mouse and human Ln‐1 were equally effective in promoting cell adhesion of all RCC cell lines. For each cell line, Ln‐10 and Ln‐10/11 were equally effective adhesive substrates, all cell lines adhering more avidly to these laminins than to mouse or human Ln‐1. As judged by inhibition assays employing specific integrin antibodies, adhesion of normal human renal proximal tubular epithelial (RPTE) cells and RCC cells from a G1 tumour to human Ln‐1 was mediated mainly by α6β1 integrin, while only the G1 RCC cells adhered to mouse Ln‐1 by using α6β1 integrin. For adhesion to Ln‐10, RPTE cells and RCC cells from a G1 tumour used an unidentified β1 integrin. Cells from G3 tumours mainly used an α3β1 integrin complex for adhesion to mouse Ln‐1 and to human Ln‐1 and Ln‐10. For all cells, adhesion to the Ln‐10/11 mixture was mediated by an unidentified integrin complex or by other adhesion molecules. These results show that laminin trimers containing the α1 chain are, in contrast to oncocytomas, abundant in the BMs of RCCs. This is in keeping with their suggested origin from renal proximal tubular epithelium known for its capacity to produce the Ln α1 chain. The results also show that RCC cells utilize complex, mainly integrin α3β1‐ and integrin α6β1‐mediated, mechanisms for adhesion to laminins. The adhesion to Ln‐1 changes from integrin α6β1 to integrin α3β1 upon increasing malignancy and, especially for Ln‐10 and Ln‐10/11, other adhesion molecules of non‐integrin type may contribute to the adhesion. Copyright © 2003 John Wiley & Sons, Ltd.
Coronary Artery Bypass Grafting via Sternotomy in Conscious Patients
Authors: Meininger Dirk , Neidhart Gerd , Bremerich Dorothee H. , Aybek Tayfun , Lischke Volker , Byhahn Christian , Kessler Paul
Published: May 2003

Abstract

The application of high thoracic epidural anesthesia (TEA) as an adjunct to general anesthesia is increasingly being used for coronary artery bypass grafting (CABG) with extracorporeal circulation. Recent developments in beating heart techniques rendered the sole use of TEA in conscious patients possible, and have been reported for single‐vessel beating heart CABG via lateral thoracotomy. For multi‐vessel revascularization, the heart is usually approached via sternotomy; therefore, the sole use of TEA was applied in awake patients who underwent CABG via sternotomy. A total of 7 patients scheduled for awake coronary artery bypass grafting (ACAB) received TEA via an epidural catheter placed at the levels of T1–2 or T2–3, respectively. Total arterial myocardial revascularization was performed after partial lower sternotomy. Besides standard monitoring, anesthetic levels were determined using an epidural scoring scale for arm movements (ESSAM). While 6 patients were awake and spontaneously breathing during the entire procedure, one patient had to be intubated intraoperatively because of respiratory distress caused by phrenic nerve palsy. Hemodynamics were stable throughout the operation. No significant arterial hypercarbia occurred. All patients rated TEA as “good” or “excellent.” We could demonstrate that the single use of TEA for CABG via sternotomy was feasible and that the patients felt well, were painfree, and remained hemodynamically stable. High patient satisfaction in our small and highly selected cohort can be reported. Because beating heart surgery in a conscious patient still carries a significant risk, further randomized controlled trials are mandatory to definitively evaluate the role of sole TEA in cardiac surgery.
Quantitative Determinations of Duodenogastric Reflux, Prevalence of Helicobacter pylori Infection, and Concentrations of Interleukin‐8
Authors: Fukuhara Kenichiro , Osugi Harushi , Takada Nobuyasu , Takemura Masashi , Ohmoto Yasukazu , Kinoshita Hiroaki
Published: May 2003

Abstract

Billroth I or II reconstruction after distal gastrectomy often is associated with inflammation in the gastric remnant. We sought to determine which reconstructive procedure was most effective in preventing such remnant gastritis. Patients undergoing curative distal gastrectomy for cancer (n = 82) were classified as group A (Roux‐en‐Y, n = 22); group B (Billroth I, n = 40); or group C (Billroth II, n = 20). Interleukin (IL)‐8 concentrations in gastric mucosa were measured 3 months after surgery. In the absence of Helicobacter pylori infection, IL‐8 concentrations were 13, 56, and 87 pg/mg protein in groups A, B, and C, respectively (p < 0.05). In the presence of H. pylori infection, IL‐8 concentrations were 61, 161, and 234 pg/mg protein in groups A, B, and C (p < 0.01). Roux‐en‐Y reconstruction is better able to prevent remnant gastritis than either the Billroth I or II procedure as judged from IL‐8 concentrations in gastric remnant mucosa.
Lymph Node Micrometastases in Early Gastric Cancer and Their Impact on Prognosis
Authors: Morgagni Paolo , Saragoni Luca , Scarpi Emanuela , Zattini Pier Sante , Zaccaroni Alberto , Morgagni Diana , Bazzocchi Francesca
Published: May 2003

Abstract

While the presence of lymph node metastases in early gastric cancer (EGC) is the most significant prognostic factor, the relevance of lymph node micrometastases remains uncertain. The authors studied 5400 lymph nodes dissected from 300 patients treated surgically for EGC between 1976 and 1999, all of whom were histologically pN0. Micrometastases were defined as single or small clusters of neoplastic cells identifiable only by immunohistochemical methods. Lymph node micrometastases were observed in 30 of the 300 patients (10%). No significant correlation was observed between micrometastases and other clinicopathological characteristics. Analysis of overall survival showed no significant difference between positive or negative micrometastasis groups. The results of our study show that the presence of lymph node micrometastases in EGC does not influence patient prognosis.
Assignment of hyperfine‐shifted heme carbon resonances in ferricytochrome b5
Authors: Lee Kang-Bong , Kweon Jeehye , Park Hokoon
Published: May 2003

The reverse detection heteronuclear multiple quantum coherence, HMQC, study of native bovine ferricytochrome b
5 has provided the complete assignment of hyperfine shifted resonances of heme carbons attached proton(s). The dominant delocalized π‐spin density to vinyl groups gives rise to contact shifts which have opposite direction for a carbon and its attached proton(s). The most hyperfine shifted 13C heme signals are mainly generated from 3rd heme pyrrole ring substituents which identifies that the molecular orbital for facile electron transfer is oriented to exposed heme edge. Magnetic/electronic asymmetry of heme induced by two axial His makes spread the hyperfine shifted heme carbon resonances over the range of 280 ppm at 25°C, which would be the more sensitive probe than those of proton resonances in characterizing the nature of heme electronic structure of ferricytochrome b
5.
Production of functional chick liver HMG 2a protein in Escherichia coli
Authors: Oka Tatsuzo , Sasakawa Takayo , Miyamoto Ken-ichi , Kuwahata Masashi , Sassa Toshihiro , Horiuchi Saburou , Natori Yasuo
Published: May 2003

An efficient Escherichia coli system for the production of a variant form of high‐mobility group‐2a protein (HMG 2a), having the additional 5 amino acid residues (Ala‐Pro‐Thr‐Leu‐Glu) at the NH2‐terminal, has been constructed. cDNA encoding HMG 2a was ligated with the Omp A signal peptide sequence and was inserted into an inducible bacterial expression vector pSH‐L. After the plasmid introduced into E. coli was expressed by temperature shift, the recombinant product was purified by trichloacetic acid precipitation followed by Bio‐Rex 70 column chromatography. The purified product showed the expected NH2‐terminal sequence and the superhelical activity of circular DNA similar to the authentic HMG 2a isolated from chick liver.
Tetrahydropyrimidine derivatives inhibit binding of a Tat‐like, arginine‐containing peptide, to HIV TAR RNA in vitro
Authors: Lapidot Aviva , Ben-Asher Edna , Eisenstein Miriam
Published: May 2003

The ability of a small molecule, 2‐methyl,4‐carboxy,5‐hydroxy‐3,4,5,6‐tetrahydropyrimidine (THP(A)), which accumulates intracellularly in various streptomyces, to inhibit the interaction of Tat peptide (R52) with TAR RNA is presented. Using gel‐shift assay, we found that the inhibition constant K
i of THP(A) is 50–100 nM, which is in the range of the binding constants of Tat peptide and protein. THP(A) is ∼ 106 times more tightly bound than the free l‐arginine. The high binding affinity may be attributed to the special delocalized positive charge on the NCN group and the hydroxyl group at the 5 position of this molecule. A model for THP(A)‐TAR interaction, analogous to the arginine guanidinum group‐TAR interaction, is presented. The relatively high uptake of THP(A) by mammalian cells warrants in vivo Tat/TAR inhibition studies.
Cloning, functional expression and mRNA distribution of an inwardly rectifying potassium channel protein
Authors: Falk Torsten , meyerhof Wolfgang , Corrette Brian J. , Schäfer Judith , Bauer Christiane K. , Schwarz Jürgen R. , Richter Dietmar
Published: May 2003

In GH3/B6 cells at least two different inward K+ currents are observed that are regulated by thyrotropin‐releasing hormone and somatostatin, respectively. Using a polymerase chain reaction based approach a cDNA was isolated and functionally expressed in human embryonic kidney cells that encodes an inward rectifier K+ channel, rIRK3, with a predicted molecular mass of 49.7 kDa. Corresponding transcripts of 2.6 kb have been detected in rat brain, pituitary and GH3/B6 cells. In situ hybridization revealed that rIRK3 mRNA is distributed throughout the brain and occurs predominantly in the piriform cortex, indusium griseum, supraoptic nucleus, facial nucleus and cerebellar Purkinje cells.
A protein related to a proteasomal subunit binds to the intracellular domain of the p55 TNF receptor upstream to its ‘death domain’
Authors: Boldin Mark P. , Mett Igor L. , Wallach David
Published: May 2003

A novel protein that binds specifically to the intracellular domain of the p55 tumor necrosis factor (TNF) receptor was cloned by two‐hybrid screening of a HeLa cell cDNA library. Data bank searches revealed high sequence similarity of the protein (55.11) to yeast, nematode and plant proteins, whose functions are yet unknown. Significant similarity was also found between 55.11 and SEN3, the yeast equivalent of the p112 subunit of the 26S proteasome. Deletion analysis showed that the protein binds to the p55 receptor upstream to the region involved in induction of cell death.
Dystrophin‐associated protein A0 is a homologue of the Torpedo 87K protein
Authors: Yoshida Mikiharu , Yamamoto Hideko , Noguchi Satoru , Mizuno Yuji , Hagiwara Yasuko , Ozawa Eijiro
Published: May 2003

We raised a monoclonal antibody, MA0, which reacts with A0, a 94‐kDa rabbit skeletal muscle dystrophin‐associated protein (DAP) bound to the syntrophin‐binding domain of dystrophin. The antibody also reacted with the 62‐kDa DAP which was moved to the locus close to β‐syntrophins by 2‐dimensional PAGE, but the DAP did not coincide with any known β‐syntrophins. We have cloned a fragment of cDNA which codes the protein reacting with MA0 from a neonatal rabbit heart cDNA library. Based on the coincidence of cDNA sequences and the similarity in molecular mass, we concluded that the proteins reacting with MA0 are rabbit homologues of the Torpedo 87K protein.
Phosphatidylinositol 3‐kinase regulation of fluid phase endocytosis
Authors: Clague Michael J. , Thorpe Catherine , Jones Arwyn T.
Published: May 2003

Endocytosis of the fluid phase marker, horse radish peroxidase, into baby hamster kidney cells is inhibited by treatment of cells with the fungal metabolite wortmannin. The IC50 of approximately 5 nM is consistent with the well‐described action of wortmannin upon phosphatidylinositol (PI) 3‐kinase. Analysis of the kinetics of uptake indicates a > 50% decrease in the initial rate of marker internalisation, a concomitant decrease in the volume of the early endosome and an increased efficiency of recycling of that marker which is internalised. As PI 3‐kinase binds to activated growth factor receptors our data suggest that receptor activation can be coupled to receptor internalisation (down regulation) by localising PI 3‐kinase stimulation of endocytosis.
Activation of neutral trehalase by glucose and nitrogen source in Schizosaccharomyces pombe strains deficient in cAMP‐dependent protein kinase activity
Authors: Soto T. , Fernández J. , Vicente-Soler J. , Cansado J. , Gacto M.
Published: May 2003

Schizosaccharomyces pombe cells carrying a disruption in the PKAI gene, that encodes the catalytic subunit of cAMP‐dependent protein kinase (PKA), lacked the glucose‐ and nitrogen‐source‐induced activation of trehalase at stationary‐phase but rised trehalase activity in response to these compounds during the exponential phase of growth. Treatment by phosphatase of either glucose‐ or nitrogen‐source‐activated trehalase resulted in trehalase deactivation suggesting that phosphorylation of the enzyme protein occurs during activation. These data indicate that in growing cells of this yeast the mechanism responsible for the activation of trehalase can be independent of interactions with free catalytic subunits of PKA and related to a signaling pathway involving a type of protein kinase different from PKA.
The trans‐inhibitory Rep78 protein of adeno‐associated virus binds to TAR region DNA of the human immunodeficiency virus type 1 long terminal repeat
Authors: Batchu Ramesh B. , Hermonat Paul L.
Published: May 2003

]he large rep gene products, Rep78 and Rep68, of adeno‐associated virus (AAV) are pleiotropic effector proteins which are required for AAV DNA replication and the trans‐regulation of AAV gene expression. Apart from these essential functions prerequisite for the life cycle of AAV, these rep products are able to inhibit the replication and gene expression of human immunodeficiency virus type 1 (HIV‐1) and a number of DNA viruses. Here, it is demonstrated that Rep78, as a chimeric with the maltose binding protein, directly binds the full‐length HIV‐1 long terminal repeat (LTR), and to a subset of these sequences containing the trans‐activation response (TAR) sequence as DNA. These interactions, an effector protein physically binding a target promoter, suggest a direct mechanism of action for Rep78 inhibition. Furthermore, competitive binding studies between the TAR region and the full‐length HIV‐LTR, strongly suggested that another site(s) within the LTR was also bound by Rep78. Finally, as Rep78 binding is also believed to be affected by secondary structure within the DNA, it was found that Rep78 preferentially binds with HIV‐LTR sequences with promoted secondary structure generated by heat denaturation and rapid cooling.
Investigation of transphosphorylation between chemotaxis proteins and the phosphoenolpyruvate: sugar phosphotransferase system
Authors: Johnson Mark S. , Rowsell Edward H. , Taylor Barry L.
Published: May 2003

Transphosphorylation between the chemotaxis proteins and phosphoenolpyruvate:sugar phosphotransferase system (PTS) from Escherichia coli was investigated by incubating the CheA, CheW and CheY proteins of the chemotaxis cascade, and Enzyme I, HPr and Enzyme IImtl of the PTS with [γ‐32P]ATP or [32P]phosphoenolpyruvate in the presence and absence of cell extract. In the absence of cell extract, ATP phosphorylated CheA, but in the presence of cell extract, Enzyme I was also phosphorylated. Phosphoenolpyruvate phosphorylated only PTS components. The transphosphorylation of Enzyme I by ATP did not require chemotaxis proteins, and likely occurred through acetate kinase. Regardless of phosphorylation state, the HPr protein did not inhibit the rate of ATP‐dependent phosphorylation of the CheA or the CheY protein. It is concluded that chemotaxis to PTS substrates is not mediated by transphosphorylation between the PTS and chemotaxis systems.
Crystal structure of Bacillus licheniformis 1,3‐1,4‐β‐d‐glucan 4‐glucanohydrolase at 1.8 Å resolution
Authors: Hahn Michael , Pons Jaume , Planas Antoni , Querol Enrique , Heinemann Udo
Published: May 2003

The crystal structure of the 1,3‐1,4‐β‐d‐glucan 4‐glucanohydrolase from Bacillus licheniformis is solved at a resolution of 1.8 Å and refined to R = 16.5%. The protein has a similar β‐sandwich structure as the homologous enzyme from Bacillus macerans and the hybrid H(A16‐M). This demonstrates that the jellyroll fold of these proteins is remarkably rigid and only weakly influenced by crystal contacts. The crystal structure permits to extend mechanistic considerations derived for the B. licheniformis enzyme to the entire class of bacterial 1,3‐1,4‐β‐d‐glucan 4‐glucanohydrolases.
A region of the 75 kDa neurotrophin receptor homologous to the death domains of TNFR‐I and Fas
Authors: Chapman Barbara S.
Published: May 2003

Members of the NTR/TNFR family mediate apoptosis in many tissues, yet sequence homology has not been detected in their intracellular domains except for a ‘death domain’ in TNFR‐I and Fas. Here, a region of the 75 kDa neurotrophin receptor (NTR) has been aligned with this apoptosis‐inducing motif. Peptides at the carboxyl terminus of each domain potentially form amphiphilic helices, one of which (in NTR) resembles mastoparan, a G‐protein activating peptide. Molecular models of three death‐region peptides suggest that observed sequence similarities reflect a common structure, perhaps capable of undergoing an induced coil to helix transition.
Rapid purification of malate synthase from cotyledons of Brassica napus L
Authors: Hoppe Andreas , Theimer Roland R.
Published: May 2003

A rapid and efficient method for the purification of malate synthase, an enzyme uniquely confined to glyoxysomes, from cotyledons of Brassica napus L. has been developed. The two step purification procedure is based on the consequent utilization of the tendency of malate synthase to form high molecular weight aggregates. Malate synthase was purified 75‐fold to apparent homogeneity with a specific activity of 180 nkat/mg protein. The estimated molecular weight of malate synthase subunits was 63 kDa. Polyclonal antibodies raised against malate synthase in rabbits detect on Western blots only one single polypeptide with an identical molecular weight.
Nitrogen oxide‐induced autoprotection in isolated rat hepatocytes
Authors: Kim Young-Myeong , Bergonia Hector , Lancaster Jack R.
Published: May 2003

Pretreatment of rat hepatocytes with low‐dose nitrogen oxide (addition of SNAP in vitro or induction of nitric oxide synthase in vitro or in vivo) imparts resistance to killing and decrease in aconitase and mitochondrial electron transfer from a second exposure to a higher dose of SNAP. Induction of this resistance is prevented by cycloheximide, indicating upregulation of protective protein(s). Ferritin levels are increased as are nonheme iron‐NO EPR signals. Tin‐protoporphyrin (SnPP) prevents protection, suggesting involvement of hsp32 (heme oxygenase) and/or guanylyl cyclase (GC). Cross‐resistance to H2O2 killing is also observed, which is also prevented by cycloheximide and SnPP. Thus, hepatocytes possess inducible protective mechanisms against nitrogen oxide and reactive oxygen toxicity.
DNA strand breakage and base modification induced by hydrogen peroxide treatment of human respiratory tract epithelial cells
Authors: Spencer Jeremy P.E. , Jenner Andrew , Chimel Ken , Aruoma Okezie I. , Cross Carroll E. , Wu Reen , Halliwell Barry
Published: May 2003

Treatment of human respiratory tract epithelial cells with H2O2 led to concentration‐dependent DNA strand breakage that was highly‐correlated with multiple chemical modifications of all four DNA bases, suggesting that damage is due to hydroxyl radical, OH.. However, the major base damage occurred to adenine. Hence, conclusions made about the occurrence and the extent of oxidative DNA damage on the basis only of changes in 8‐hydroxyguanine should be approached with caution.
Ribozyme mediated cleavage of acute phase serum amyloid A (A‐SAA) mRNA in vitro
Authors: Gaughan Derval J. , Steel Diana M. , Whitehead Alexander S.
Published: May 2003

The 1000‐fold induction of acute phase serum amyloid A (A‐SAA) in the liver during inflammation indicates that this protein plays an important, though ill‐defined, role in host defence. Paradoxically, prolonged overproduction of A‐SAA is a causative factor in secondary amyloidosis and possibly other diseases such as atherosclerosis; the ability to down‐regulate A‐SAA synthesis is therefore of considerable clinical importance. We have successfully generated anti‐SAA hammerhead ribozymes and we report that they are capable of cleaving A‐SAA mRNA in vitro.
Divergent sequence motifs correlated with the substrate specificity of (methyl)malonyl‐CoA:acyl carrier protein transacylase domains in modular polyketide synthases
Authors: Haydock Stephen F. , Aparicio Jesús F. , Molnár István , Schwecke Torsten , Khaw Lake Ee , König Ariane , Marsden Andrew F.A. , Galloway Ian S. , Staunton James , Leadlay Peter F.
Published: May 2003

The amino acid sequences of a large number of polyketide synthase domains that catalyse the transacylation of either methylmalonyl‐CoA or malonyl‐CoA onto acyl carrier protein (ACP) have been compared. Regions were identified in which the acyltransferase sequences diverged according to whether they were specific for malonyl‐CoA or methylmalonyl‐CoA. These differences are sufficiently clear to allow unambiguous assignment of newly‐sequenced acyltransferase domains in modular polyketide synthases. Comparison with the recently‐determined structure of the malonyltransferase from Escherichia coli fatty acid synthase showed that the divergent region thus identified lies near the acyltransferase active site, though not close enough to make direct contact with bound substrate.
The GA module, a mobile albumin‐binding bacterial domain, adopts a three‐helix‐bundle structure
Authors: Johansson Maria U. , de Château Maarten , Björck Lars , Forsén Sture , Drakenberg Torbjörn , Wikström Mats
Published: May 2003

We present the first study of the secondary structure and global fold of an albumin‐binding domain. Our data show that the GA module from protein PAB, an albumin‐binding protein from the anaerobic bacterial species Peptostreptococcus magnus, is composed of a left‐handed three‐helix bundle. The helical regions were identified by sequential and medium range NOEs, values of NH‐CαH coupling constants, chemical shift indices, and the presence of slowly exchanging amide protons, as determined by NMR spectroscopy. In addition, circular dichroism studies show that the module is remarkably stable with respect to both pH and temperature.
Construction of a divalent cell adhesive lysozyme by introducing the Arg‐Gly‐Asp sequence at two sites
Authors: Yamada Takao , Shimada Yoshimi , Uyeda Atsuko , Sugiyama Shigeru , Kikuchi Masakazu
Published: May 2003

To increase the cell adhesion activity of 74RGD4, an RGDS‐inserted mutant between Val74 and Asn75 of human lysozyme, one more site for the RGD introduction was investigated in the lysozyme molecule. We found that 47RGD4 with RGDS in place of AGDR (residues 47 to 50) in a β‐turn region possesses the same level of adhesion activity as that of 74RGD4. The acceptance of the RGD introduction in the β‐turn region of human lysozyme is in good agreement with recent studies on the functional conformation of RGD. We constructed (47,74)RGD4, a mutant containing RGD at two sites, by combining the N‐terminal domain of 47RGD4 and the C‐terminal domain of 74RGD4. The (47,74)RGD4 lysozyme, with two functional RGD sequences, exhibits even higher cell adhesion activity than that of 74RGD4 or 47RGD4.
Molecular and functional characterization of a partial cDNA encoding a novel chicken brain melatonin receptor
Authors: Liu F. , Yuan H. , Sugamori K.S. , Hamadanizadeh A. , Lee F.J.S. , Pang S.F. , Brown G.M. , Pristupa Z.B. , Niznik H.B.
Published: May 2003

An approach based on homology probing was used to clone a partial cDNA encoding a novel melatonin (ML) receptor (MLR) from chicken (Gallus domesticus) brain. Based on available deduced amino‐acid sequence, the chicken MLR (cMLR) displayed greater sequence homology to the frog (Xenopus) MLR than cloned human/mammalian receptors, with overall identities of 73% and 66%, respectively. In order to gain functional expression, a chimeric frog/chicken (flc)MLR was constructed in which the 5′ end of the cMLR, including the N‐terminus, TM1 and part of the first intracellular loop was substituted by fMLR sequence. [125I]Iodo‐ML bound with high affinity (K
d of ∼35 pM) to COS‐7 cells transiently expressing the flcMLR in a saturable and guanine nucleotide‐sensitive manner with the following rank order of potency: 2‐iodo‐ML > ML > 6‐Cl‐ML > S20750 > 6‐OH‐ML > S20643 > S20753 > N‐acetyl‐5HT > > 5‐HT. Estimated K
i values for these compounds at the flcMLR correlated well to those obtained in native chicken brain membranes. In line with the observed structural similarity to the fMLR, the flcMLR exhibited affinities for ML, 6‐Cl‐ML and 6‐OH‐ML ∼10‐fold lower than mammalian receptors. Functionally, opposing interactions between ML and dopamine receptor signal transduction pathways were observed with ML potently inhibiting dopamine D1A‐receptor‐mediated cAMP accumulation in cells (HEK‐293) transiently co‐expressing these receptors. cMLR mRNAs were found expressed in chicken brain and kidney with trace levels observed in the lung. The availability of cloned vertebrate MLRs distinct at both the amino acid and pharmacological level from their mammalian counterparts may now allow for the identification of those amino‐acid residues and structural motifs that regulate ML‐binding specificity and affinity.