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At least 19 recordsLinked to original sources
PubMed1985

Knee extension torque during repeated knee extension-flexion reversals and separated knee extension-flexion dyads.

I measured the knee extension torque, produced by eight hemiparetic patients during repeated knee extension-flexion reversals and during separated knee extension-flexion dyads, to determine the effect of "reversal of antagonists" on knee extension torque. The hemiparesis in these eight patients was secondary to intracranial lesions. I tested their involved lower extremity on an isokinetic dynamometer at 60 degrees/sec. Using a sequential medical-trials design, I found knee extension torque to be significantly greater during repeated knee extension-flexion reversals than during separated knee extension-flexion dyads (p less than .05). I, therefore, concluded that reversal of antagonists may facilitate knee extension torque production in the type of patients tested, under the specific conditions of their testing.

Adult↗
PubMed2006

Prognostic significance of extrathyroid extension of papillary thyroid carcinoma: massive but not minimal extension affects the relapse-free survival.

OBJECTIVES: Extrathyroid extension has been recognized as a prognostic factor in papillary thyroid carcinoma. In the most recent version of the UICC TNM classification system, extrathyroid extension has been classified into two grades, minimal extension (extension to sternothyroid muscle or perithyroid soft tissues) and massive extension (extension to subcutaneous soft tissue, larynx, trachea, esophagus, or recurrent laryngeal nerve). In this study, we investigated the prognostic significance of each of the two types of extension. PATIENTS AND METHODS: One thousand and sixty-seven patients with papillary thyroid carcinoma without distant metastasis at surgery, who underwent surgical treatment in Kuma hospital between 1990 and 1995 and had been followed postoperatively for 60 months or more, were enrolled in this study. The grading of extrathyroid extension was based on both pathological findings and intraoperative surgical findings. RESULTS: In univariate analysis, although patients with massive extension showed a significantly worse relapse-free survival (RFS) rate than those with no or minimal extension (P < 0.0001), there was no difference in the RFS rate between patients with no extension and those with minimal extension. Among patients with massive extension, the RFS rate tended to be worse in those with posterior extension than in those with anterior extension (P = 0.0562). Furthermore, the RFS rate of patients with massive posterior extension only to the recurrent nerve demonstrated a better RFS rate than those with extension to other posterior organs (P = 0.0052). Multivariate analysis demonstrated that massive extrathyroid extension is recognized as an independent prognostic factor for RFS (P = 0.0003). CONCLUSIONS: These findings suggest that (1) upgrading of T category for tumors with massive extension is appropriate, whereas that for tumors with only minimal extension is not, and (2) careful surgical treatment and postoperative follow-up are required for tumors with massive extension to posterior organs other than the recurrent laryngeal nerve.

Adenocarcinoma, Papillary↗
PubMed2001

In planta regulation of extension of an endophytic fungus and maintenance of high metabolic rates in its mycelium in the absence of apical extension.

The fungus Neotyphodium lolii is an endophytic symbiont. It grows in the intercellular spaces of the perennial ryegrass Lolium perenne, producing secondary metabolites which enhance the fitness of the association over that of uninfected L. perenne. We report that the average number of hyphal strands in a given section of a leaf remains constant during the life of a leaf, indicating synchrony of leaf and hyphal extension, including cessation of hyphal extension when leaf extension ceases. We used a constitutively expressed reporter gene as an indicator of the mycelium's metabolic activity during and after hyphal extension. Reporter gene activity decreased when the mycelium stopped extending in liquid culture but not in planta. This indicates that in planta endophyte hyphae remain metabolically highly active when extension has ceased and throughout the life of the leaf they are colonizing. The behavior of the fungus in planta indicates the existence of signaling pathways which (i) synchronize the extension of leaf and hypha by regulating hyphal extension, (ii) suppress hyphal branching, and (iii) stop apical extension of fungal hyphae, without reducing the mycelium's metabolic activity. These signals may be crucial for the symbiosis, by allowing the endophyte to switch the focus of its metabolic activity from extension to the production of secondary metabolites.

Ascomycota↗
PubMed2002

Role of the C-terminal extensions of alpha-crystallins. Swapping the C-terminal extension of alpha-crystallin to alphaB-crystallin results in enhanced chaperone activity.

Several small heat shock proteins contain a well conserved alpha-crystallin domain, flanked by an N-terminal domain and a C-terminal extension, both of which vary in length and sequence. The structural and functional role of the C-terminal extension of small heat shock proteins, particularly of alphaA- and alphaB-crystallins, is not well understood. We have swapped the C-terminal extensions between alphaA- and alphaB-crystallins and generated two novel chimeric proteins, alphaABc and alphaBAc. We have investigated the domain-swapped chimeras for structural and functional alterations. We have used thermal and non-thermal models of protein aggregation and found that the chimeric alphaB with the C-terminal extension of alphaA-crystallin, alphaBAc, exhibits dramatically enhanced chaperone-like activity. Interestingly, however, the chimeric alphaA with the C-terminal extension of alphaB-crystallin, alphaABc, has almost lost its activity. Pyrene solubilization and bis-1-anilino-8-naphthalenesulfonate binding studies show that alphaBAc exhibits more solvent-exposed hydrophobic pockets than alphaA, alphaB, or alphaABc. Significant tertiary structural changes are revealed by tryptophan fluorescence and near-UV CD studies upon swapping the C-terminal extensions. The far-UV CD spectrum of alphaBAc differs from that of alphaB-crystallin whereas that of alphaABc overlaps with that of alphaA-crystallin. Gel filtration chromatography shows alteration in the size of the proteins upon swapping the C-terminal extensions. Our study demonstrates that the unstructured C-terminal extensions play a crucial role in the structure and chaperone activity, in addition to generally believed electrostatic "solubilizer" function.

Amino Acid Sequence↗
PubMed2005

[Repair of the knee extension apparatus in the treatment of "extension contracture" after femoral lengthening].

UNLABELLED: Restriction of the knee flexion is one of the most frequent complications during femoral lengthening with Ilizarov method. In most severe cases the knee flexion reaches less than 90 degrees, which leads to impairment of patient's activity ("extension knee contracture") and represents difficult clinical problem to manage. MATERIAL: We reviewed 4 patients at the age of 14 to 22 years (mean 19), treated surgically because of severe knee flexion limitation as a complication of femoral lengthening with the Ilizarov method. The mean age at femoral lengthening was 17 years (12 to 20). The indication for lengthening was femoral shortening from 5 to 12 cm (mean 7.5) because of myelodysplasia with club foot deformity (1 case), fibular hemimelia (1 case), sequelae of septic arthritis (1 case) and Ollier disease (1 case). Lengthening with Italian modification of Ilizarov device was used in all cases. In two patients with knee instability the apparatus was extended to stabilize the knee joint (in one case tibial and femoral lengthening was made simultaneously). Femoral lengthening of 5 to 12 cm (mean 7.5) was achieved. Knee flexion before lengthening varied from 90 degrees to 150 degrees (mean 135 degrees) and after femoral lengthening decreased to 41 degrees (20 to 75 degrees). METHOD: Plasty of knee extension apparatus was done 16 months after removal of the Ilizarov device. The procedure includes extensive release of subcutaneous and fascial adhesions around the knee joint (4 patient), patellar retinaculum and ilio-tibial tract release (4 patient), lengthening of vastus lateralis muscle (4 patients), vastus medialis (2 patients) and vastus intermedius (1 patient), mobilization of patello-femoral joint (3 patients), fractional, intramuscular lengthening of rectus femoris 15 cm above the knee joint (2 patients). Intraoperatively 90 degrees flexion was achieved (80 degrees to 100 degrees). In after treatment plaster cast with knee flexion 45 degrees was used. After 4-5 days passive exercises were started using K2 apparatus (continuous passive knee motion) and posterior slabs: one with knee extension for walking and second with knee flexion at the night were used. Active exercises began at the 10th day after surgery. RESULTS: At follow up 10 to 47 months (mean 36) after surgery 105 degrees to 120 degrees of knee flexion (mean 114 degrees) was achieved with full passive and active knee extension at good muscle power. All joints were evaluated as stable in sagittal and coronal planes (including 2 joints with mild instability in coronal plane before surgery). CONCLUSIONS: 1. Femoral lengthening procedure should be realized with proper attention to prophylaxis of knee extension contracture. 2. Knee extension apparatus plasty is effective and save procedure for treatment of so called "extension knee contracture" as a complication of femoral lengthening.

Adolescent↗
PubMed1987

Effects of prone spinal extension exercise on passive lumbar extension range of motion.

The purpose of this study was to determine the effectiveness of prone spinal extension exercises for increasing passive lumbar extension range of motion in healthy young adults. Eighteen healthy female and 18 healthy male volunteers were divided randomly into control groups (women, n = 10; men, n = 8) and experimental groups (women, n = 8; men, n = 10). The experimental groups performed 20 repetitions of a prone extension exercise each day for four weeks; the control groups did not. We used spondylometry to measure lumbar extension ROM. The exercises produced a significant difference (p less than .025) in the passive lumbar extension ROM between the male experimental and control groups preventing a loss of spinal mobility in the men who exercised. Analysis of the data revealed no significant difference between the female groups. The results are discussed in light of the clinical significance of lumbar extension ROM. We suggest further studies to examine the effects of lumbar extension exercises on patients with restricted ROM and low back pain.

Exercise Therapy↗
PubMed1994

Relative effectiveness of an extension program and a combined program of manipulation and flexion and extension exercises in patients with acute low back syndrome.

BACKGROUND AND PURPOSE: The relative effectiveness of an extension program and a manipulation program with flexion and extension exercises was examined in patients with low back syndrome. SUBJECTS: Forty-nine patients with less than a 3-month history of low back pain were seen at physical therapy clinics in western Pennsylvania, southern Mississippi, and eastern Missouri during a 6-month period. Twenty-seven of the 49 patients were classified a priori into a treatment-oriented category of extension/mobilization and were then randomly assigned to participate in an extension program or a program of manipulation followed by hand-heel rocks (flexion and extension). Two patients dropped out of the study (1 patient returned to work, and the other patient was unable to comply with the treatment schedule), and 1 patient was eliminated from the study because of magnified illness behavior. The remaining 24 patients (15 male, 9 female; mean age = 44 years, SD = 15, range = 14-73) were assigned randomly and equally to the two groups. Eight physical therapists participated in the study. METHODS: A randomized clinical trial comparing the two regimens was conducted for a 1-week period. Outcome was assessed using an Oswestry Low Back Pain Questionnaire initially (before treatment) and at 3 and 5 days posttreatment, and data were analyzed using a 2 x 3 (group x time) analysis of variance. RESULTS: A significant interaction of the group and time variables was demonstrated, indicating that the rate of positive response was greater in the manipulation/hand-heel rock group than in the extension group. CONCLUSION AND DISCUSSION: In this category of patients with low back pain, the use of manipulation as an adjunct to an ongoing exercise program appears to be warranted.

Acute Disease↗
PubMed1986

Is it possible to rule out extensive anterior myocardial infarction in the absence of abnormal Q waves in lead I and aVL? Effect of infero-apical extension of infarction over apex.

To determine whether abnormal Q wave in lead I or aVL may be of use to estimate the size of an extensive anterior myocardial infarction, electrocardiographic and left ventriculographic findings were analyzed in 45 patients with old extensive anterior infarction. All 45 patients had a significant narrowing in the proximal segment of left anterior descending coronary artery (LAD) and severe asynergy in anterolateral segment. The patients were divided into two groups; Group I consisted of 35 cases with less involvement of the inferoapical segment and Group II of 10 cases with remarkable extension of the anterolateral infarction into the inferoapical segment due to occlusion of very long LAD supplying the anterior half of posterior interventricular groove. There were no statistical differences in the extent of anterolateral asynergy, number of abnormal Q waves in precordial leads and left ventricular ejection fraction between the two groups. While abnormal Q wave in lead I or aVL was present in 28 cases (80%) of Group I, it was observed in only 3 cases (30%) of Group II (p less than 0.01). Thus, we can't rule out extensive anterior myocardial infarction even if abnormal Q waves are absent in lead I or aVL, in which abnormal Q waves may be cancelled by loss of electromotive force of inferoapical segment due to extension of the anterior infarction over the apex in cases with extraordinarily long LAD.

Electrocardiography↗
PubMed1981

Stimulation of the extension of validamycin-inhibited hyphae by the hyphal extension factor present in Rhizoctonia solani.

Validamycin inhibited the hyphal extension of Rhizoctonia solani without growth inhibition. Hyphal inhibition was more pronounced in the main hyphae than in the primary or secondary branches of R. solani. Validamycin inhibition was antagonized by the hyphal extract of R. solani which stimulated hyphal extension. From the hyphal extract, the hyphal extension factor antagonizing the action of validamycin was isolated as a syrup after passing through an Amberlite IR-120 B column, adsorption on an Amberlite IRA-410 column, elution with 0.2 N NH4Cl and concentration of the eluate. The hyphal extension factor stimulated only the extension of the validamycin-inhibited hyphae and not that of the normal hyphae.

Antifungal Agents↗
PubMed1979

[Extensive, combined and extensive-combined operations in cancer of the cardial portion of the stomach].

The authors present an analysis of the materials obtained in the clinic during a 21-year period. Among 438 patients subjected to radical surgery for cancer of the gastric cardia in 319 cases extensive, combined and extensive-combined surgical procedures were accomplished, their characteristics being described. The regular feature of cancer of this localization is its lymphogenic spread, and this fact together with esophageal involvement allows a consideration that for cancer of the cardia, in any stage but 1, all resections, as a rule, should be extensive, combined or both. The success of the immediate results of the operation depends on adequacy of an approach, kind of operation and extent of resection combinations in relation to the characteristic of cancer spread according to TNM system and the degree of surgical risk for each individual case. Estimation of the immediate and late results should take into account the motivation for performing extensive, combined and extensive-combined procedures. In cancer of the gastric cardia the analysed surgical procedures are to be referred to a group of conventionally radical interventions.

Cardia↗
PubMed2005

The role of wall Ca2+ in the regulation of wall extensibility during the acid-induced extension of soybean hypocotyl cell walls.

We examined the acid-facilitated yielding properties of cell walls of soybean hypocotyls and the effects of Ca(2+) upon the properties by stress-strain analyses using glycerinated hollow cylinders (GHCs) from the elongating regions of the hypocotyls. Stress-extension rate curves of native GHCs showed characteristic changes with pH, all indicating the existence of yield threshold tension (y) as well as wall extensibility (phi), i.e. a downward shift of y and an increase in phi with wall acidification. The acid-induced downward shift of y was inhibited by boiling of GHCs. In contrast, a considerable increase in phi with acidification remained even after boiling. This indicates that phi consists of two components, i.e. heat-sensitive and heat-resistant, both being pH sensitive. A Ca(2+) chelator (Quin 2) dramatically increased phi at a neutral pH. Subsequent addition of Ca(2+) or ruthenium red suppressed the chelator-induced increase in phi. These findings suggest that wall Ca(2+) plays an important role in the regulation of wall extensibility during the acid-induced wall extension by reacting with carboxyl groups of wall pectin.

Calcium↗
PubMed2001

Supracondylar extension fracture of the humerus in children. Manipulative reduction, immobilisation and fixation using a U-shaped plaster slab with the elbow in full extension.

We present a method of manipulative reduction, immobilisation and fixation using a U-shaped plaster with the elbow in extension for extension-type supracondylar fractures of the humerus in children. When the elbow is in full extension, both the extensor and the flexor muscles are neutralised during manipulative reduction and the carrying angle can be easily assessed thus preventing cubitus varus, the most common complication. In order to evaluate the efficiency of this method, we compared the clinical results of the new method with those of conventional treatment. In a group of 95 children who sustained an extension-type supracondylar fracture of the humerus, 49 were treated by the new method and 46 by the conventional method, reduction and immobilisation in a plaster slab with the elbow in flexion. Reduction and immobilisation were easily achieved and reliably maintained by one manipulation for all the children treated by the new method. In 12 children treated by the conventional method, the initial reduction failed and in seven secondary displacement of the distal fragment occurred during the period of immobilisation in plaster. All required a second or third manipulation. Of the 46 children, 28 (60.9%) had developed cubitus varus at a mean follow-up of 4.6 years when treated by the conventional method. None of the children treated by the new method developed cubitus varus. The mean score, according to the Hospital for Special Surgery (HSS) elbow scoring system, was 91 points using the new method and 78 with the conventional method. The results were statistically significant with regard to the incidence of cubitus varus and the elbow score (p < 0.01) suggesting that the new method is reliable and gives a satisfactory outcome.

Adolescent↗
PubMed1990

Primer extension dideoxy chain termination nucleotide sequencing of partially purified RNA virus genomes: a technique for investigating low titre viruses with extensive genome secondary structure.

A modified version of the primer extension dideoxy chain termination nucleotide sequencing technique (Sanger et al., 1977) is described. This method has advantages over existing molecular cloning and primer extension techniques in that it allows the genome of RNA viruses to be directly sequenced from partially purified RNA preparations. Thus, viruses growing at unacceptably low titres in tissue culture can now be partially purified from infected mouse brain and sequenced. The technique also incorporates steps for the denaturation of secondary structure which has previously provided difficulties for primer extension sequencing.

Animals↗
PubMed1999

Low-grade endometrial stromal sarcoma with intracardiac extension. Evolution of extensive smooth muscle differentiation and usefulness of immunohistochemistry for its recognition and distinction from intravenous leiomyomatosis.

This case, a rare example of low-grade endometrial stroma sarcoma with extensive smooth muscle differentiation which extended to the inferior vena cava and cardiac chambers closely resembling intravenous leiomyomatosis grossly and microscopically, illustrates the importance of extensive sectioning and the usefulness of immunohistochemistry. Although spindle cell components arranged in interlacing bundles consistent with smooth muscle differentiation were recognizable in the primary tumor (on retrospective review), extensive smooth muscle differentiation in the recurrent tumors masked prototypical morphologic features of stromal sarcoma and only small neoplastic stromal components were preserved in limited areas, leading to initial failure to distinguish the lesion from intravenous leiomyomatosis. The immunophenotyping disclosed two distinct cell populations in the tumor: i.e. vimentin-positive and smooth muscle marker negative stromal cells, and vimentin-negative spindle-shaped desmin-positive smooth muscle cells. Our observation suggests that the predominance of a smooth muscle component in such a tumor can be misleading and does not always warrant a diagnosis of intravenous leiomyomatosis, nor does it predict a benign clinical course. This case also provides an insight into the relationship of the endometrial stroma and myometrium, and their cell of origin and the histogenesis of endometrial stromal sarcoma.

Actins↗
PubMed2000

Poly-N-acetyllactosamine extension in N-glycans and core 2- and core 4-branched O-glycans is differentially controlled by i-extension enzyme and different members of the beta 1,4-galactosyltransferase gene family.

Poly-N-acetyllactosamines are attached to N-glycans, O-glycans, and glycolipids and serve as underlying glycans that provide functional oligosaccharides such as sialyl Lewis(X). Poly-N-acetyllactosaminyl repeats are synthesized by the alternate addition of beta1,3-linked GlcNAc and beta1,4-linked Gal by i-extension enzyme (iGnT) and a member of the beta1,4-galactosyltransferase (beta4Gal-T) gene family. In the present study, we first found that poly-N-acetyllactosamines in N-glycans are most efficiently synthesized by beta4Gal-TI and iGnT. We also found that iGnT acts less efficiently on acceptors containing increasing numbers of N-acetyllactosamine repeats, in contrast to beta4Gal-TI, which exhibits no significant change. In O-glycan biosynthesis, N-acetyllactosamine extension of core 4 branches was found to be synthesized most efficiently by iGnT and beta4Gal-TI, in contrast to core 2 branch synthesis, which requires iGnT and beta4Gal-TIV. Poly-N-acetyllactosamine extension of core 4 branches is, however, less efficient than that of N-glycans or core 2 branches. Such inefficiency is apparently due to competition between a donor substrate and acceptor in both galactosylation and N-acetylglucosaminylation, since a core 4-branched acceptor contains both Gal and GlcNAc terminals. These results, taken together, indicate that poly-N-acetyllactosamine synthesis in N-glycans and core 2- and core 4-branched O-glycans is achieved by iGnT and distinct members of the beta4Gal-T gene family. The results also exemplify intricate interactions between acceptors and specific glycosyltransferases, which play important roles in how poly-N-acetyllactosamines are synthesized in different acceptor molecules.

Animals↗
PubMed1990

Wall extensibility and gravitropic curvature of sunflower hypocotyls: correlation between timing of curvature and changes in extensibility.

Gravitropic curvature results from unequal growth rates on the upper and lower sides of horizontal stems. These unequal growth rates could be due to differences in wall extensibility between the two sides. To test this, the time course of curvature of horizontal sunflower (Helianthus annuus L.) hypocotyls was determined and compared with the time courses of changes in Instron-measured wall extensibility (PEx) of the upper and lower epidermal layers. As gravicurvature developed, so did the difference in PEx between the upper and lower epidermis. The enhanced growth rate on the lower side during the period of maximum increase in curvature was matched by PEx values greater than those of the vertical control, while the inhibited growth rate on the upper side was accompanied by PEx values below that of the control. The close correlation between changes in growth rates and alterations in PEx demonstrates that changes in wall extensibility play a major role in controlling gravicurvature.

Cell Division↗
PubMed1995

Extensive head burns corrected by scalp extension.

BACKGROUND: Scalp extension has been revealed as a good corrective method for androgenetic alopecia and it is possible to foresee its other probable applications in the field of increasing hair-bearing areas. OBJECTIVE: The performance of Frechet's scalp extender in selected head burn cases allows the possibility of maintaining a high degree of social presentability during the patient's entire treatment period, on condition that this procedure or others are repeated. METHODS: The author discusses his experience in correcting an extensive head burn and the performance of Frechet's extender. CONCLUSION: In our experience scalp extension showed itself to be a valid method for the correction of a burned area, reducing it considerably and reducing total treatment time compared with traditional techniques. Also the patient has the advantage of normal social presentability during the entire treatment period.

Adult↗
PubMed2003

Successful rotational atherectomy in the setting of extensive coronary dissection: a case of failed balloon angioplasty in a nondilatable calcified lesion complicated by balloon rupture and extensive dissection.

We describe a case of rotational atherectomy (RA) used in the setting of extensive coronary dissection. Unsuccessful predilitation of a heavily calcified proximal LAD stenosis resulted in balloon rupture, which produced occlusive dissection extending into the mid LAD. Limited options for this patient required that we perform RA to permit stent delivery and deployment and avoid anterior myocardial infarction. A brief discussion of reasons for balloon angioplasty failure and the potential role for subsequent RA is given. Predictors for coronary perforation when performing RA are reviewed. Our rationale and strategy to avoid the increased risk of perforation with RA in this contraindicated setting of extensive dissection is given.

Aged↗