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1.
J Biol Regul Homeost Agents ; 35(2): 441-456, 2021.
Article in English | MEDLINE | ID: mdl-33940790

ABSTRACT

Good fundamentals of posture and balance are essential for the efficient performance of both simple daily tasks and more complex movement patterns. In particular, postural balance is the ability to keep the body in equilibrium and to regain balance after the shift of body segments: postural control mechanisms of integration of the visual, vestibular and foot afferential channels contribute to this. This document provides recommendations based on scientific evidence, clinical practice, and consensus between experts concerning the prevention, diagnosis, and treatment of postural dysfunction at the three stages of life as the developmental age, adult age, and old age > 65 years and follows the "National Guidelines on Classification and Measuring of Posture and its Dysfunctions" per the Italian Ministry of Health (December 2017). The paper answers four main questions: i) "Which measures can be adopted to prevent postural dysfunctions?" ii) "What can we do in order to make a correct diagnosis of postural dysfunction?" iii) "What are the correct treatment programs for postural dysfunctions?" iv) Which professional competencies and experiences are useful for preventing, diagnosing and treating postural dysfunctions? By the Consensus of the Experts and the scientific evidence, emerge that the approach to postural dysfunctions requires a multidisciplinary and interdisciplinary team. Furthermore, rehabilitation treatment interventions must be specific to the age groups that have been indicated, to consider the integration of the main systems and subsystems of postural control that change with age.


Subject(s)
Postural Balance , Posture , Consensus , Foot
2.
Can J Anaesth ; 46(8): 741-7, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10451133

ABSTRACT

PURPOSE: To test the hypothesis that the addition of a preincisional femoral 3-in-1 block to intra-articular instillation with ropivacaine 0.2% at the end of surgery improves postoperative pain control in patients undergoing arthroscopic anterior cruciate ligament reconstruction (ACLR) under general anesthesia. METHODS: In a prospective, randomized, placebo-controlled, double-blind trial, we studied 44 patients scheduled for inpatient ACLR. Prior to incision, the treatment group (n = 22) received a femoral 3-in-1 block with 40 ml ropivacaine 0.2%, augmented by infiltrations of the lateral and anteromedial incisions with 20 ml ropivacaine 0.2% at the end of the procedure. The control group (n = 22) received saline 0.9% instead of ropivacaine. All patients received an intra-articular instillation with 30 ml ropivacaine 0.2% at the end of surgery. The primary efficacy variable was 24 hr morphine consumption postoperatively standardized by weight, administered intravenously via a patient-controlled analgesia (PCA) pump. RESULTS: There was no difference between both groups in 24 hr PCA morphine consumption postoperatively (control, 0.45 +/- 0.44 [mean +/- SD] mg x kg(-1); treatment, 0.37 +/- 0.50 mg x kg(-1); p = 0.55). No difference was found in postoperative visual analog scale pain scores, adverse events, or vital signs. In the treatment group, R = 10/22 patients did not require postoperative morphine compared with R = 6/22 in the control group (P = 0.35). CONCLUSION: We found no effect of a femoral 3-in-1 block with ropivacaine 0.2% on postoperative analgesic consumption, compared to intra-articular instillation with ropivacaine 0.2% alone, in patients undergoing ACLR under general anesthesia.


Subject(s)
Amides , Analgesics, Opioid/therapeutic use , Anesthetics, Local , Arthroscopy , Femoral Nerve , Knee/surgery , Nerve Block , Pain, Postoperative/drug therapy , Adult , Analgesia, Patient-Controlled , Analgesics, Opioid/administration & dosage , Anesthesia, General , Anterior Cruciate Ligament/surgery , Double-Blind Method , Female , Humans , Injections, Intra-Articular , Male , Middle Aged , Morphine/administration & dosage , Morphine/therapeutic use , Prospective Studies , Ropivacaine
4.
Pharm Dev Technol ; 2(4): 323-34, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9552461

ABSTRACT

Polymeric microparticles containing two ceftiofur salts as antimicrobial agents for intramammary application in dry cows were prepared by modified o/w-solvent evaporation methods (dispersion or cosolvent method) or by a w/o/w-multiple emulsion solvent evaporation method. The microspheres were characterized with respect to drug loading, drug release, and morphological properties. The three methods resulted in high encapsulation efficiencies. The choice of organic solvent/solvent mixture strongly affected the structure of the microparticles; both matrix and reservoir-type structures with different porosities were obtained. Scaling up to larger batch sizes resulted in microspheres with a faster drug release. The addition of water-miscible cosolvents to the water-immiscible polymer solution allowed the preparation of microparticles from a drug solution rather than a drug dispersion. Microparticles prepared by the cosolvent method could be separated after shorter time intervals from the aqueous phase; the microspheres had a denser matrix with finely dispersed drug crystals and a slower drug release when compared with microspheres prepared by the dispersion method, which had a more porous structure with larger embedded drug crystals. The cosolvent and dispersion methods present a simple alternative to the w/o/w-solvent evaporation method for the encapsulation of water-soluble drugs with an external water phase.


Subject(s)
Cephalosporins/administration & dosage , Drug Compounding , Emulsions , Microscopy, Electron, Scanning , Particle Size , Polymers , Solubility , Water/chemistry
5.
Biochem Pharmacol ; 51(11): 1477-87, 1996 Jun 14.
Article in English | MEDLINE | ID: mdl-8630089

ABSTRACT

Squalene synthase (SQS) is a key enzyme in the biosynthetic pathway for cholesterol and is a target for improved agents to lower plasma levels of low-density lipoprotein (LDL). A series of novel 3' substituted quinuclidines have been discovered as inhibitors of the rat liver microsomal enzyme. In this study, we demonstrate the inhibitory effects in vitro and in vivo, of two examples of the series. When microsomes were preincubated with compounds, before addition of substrate, both 3-(biphenyl-4-yl)quinuclidine (BPQ) and 3-(biphenyl-4-yl)-3-hydroxyquinuclidine (BPQ-OH) were found to cause biphasic inhibition of the enzyme with apparent inhibition constants (K'i) for the sensitive phases of 12 nM and 15 nM, respectively. The K'i values for the insensitive phases were 1.8 microM and 2.9 microM, respectively. The two examples inhibited equally both steps of the SQS-catalysed reaction, as shown by parallel inhibition of 3H+ release and labelled squalene formation from [1-3H]farnesyl pyrophosphate (FPP). BPQ and BPQ-OH were shown to be inhibitors of hepatic sterol synthesis from mevalonate with ED50 values of 10.6 and 7.1 mg/kg, respectively, after acute oral administration to the rat. BPQ-OH was chosen for further study and, to determine its selectivity of effect on the mevalonate pathway in vivo, the effect of a dose of 70 mg/kg on the pattern of labelled mevalonate incorporation into the various lipid fractions of the rat liver was examined. As expected, the incorporation into squalene and sterol products was inhibited by about 70%. An appearance of label in fractions corresponding to farnesyl and geranylgeranylpyrophosphates, as well as the corresponding alcohols, was observed in treated but not control animals. In addition, the administration of compound resulted in the appearance of peaks of mevalonate-derived radioactivity in an acidic fraction believed to represent metabolites of farnesol. Such results are consistent with inhibition of the mevalonate pathway at, and not before, SQS. In contrast, there was a significant increase in the incorporation of labelled mevalonate into ubiquinone 10, and the synthesis of dolichols was apparently unchanged. The results suggest a specific effect of BPQ-OH on rat liver SQS. The compound is, therefore, an interesting lead for further investigation of this class of compounds.


Subject(s)
Enzyme Inhibitors/pharmacology , Farnesyl-Diphosphate Farnesyltransferase/antagonists & inhibitors , Liver/enzymology , Quinuclidines/pharmacology , Animals , Female , Kinetics , Liver/drug effects , Mevalonic Acid/analogs & derivatives , Mevalonic Acid/metabolism , Rats , Rats, Inbred Strains , Sensitivity and Specificity , Tritium
6.
Biochem Pharmacol ; 51(11): 1489-501, 1996 Jun 14.
Article in English | MEDLINE | ID: mdl-8630090

ABSTRACT

Squalene synthase (SQS) catalyses a step following the final branch in the pathway of cholesterol biosynthesis. Inhibition of this enzyme, therefore, is an approach for the treatment of atherosclerosis with the potential for low side effects. We have characterised the inhibition of rat liver microsomal SQS by 3-(biphenyl-4-yl)quinuclidine (BPQ). BPQ follows slow binding kinetics in that the rate of accumulation of product decreases with time if the inhibitor is added when the assay is started. Preincubation of BPQ and SQS leads to a biphasic dose-response where accumulation of product is linear with time only for the sensitive phase. When the farnesyl pyrophosphate (FPP) substrate is present at 19.6 microM, approximately 77% of the SQS activity is sensitive to the inhibitor (vOs) and the remainder is insensitive (vOi). The apparent inhibition constants (K'i values) are respectively K'is = 4.5 nM and K'ii = 1300 nM. Similar biphasic behaviour is exhibited by other inhibitors and in microsomes prepared from human and marmoset liver. As the concentration of FPP is reduced below 19.6 microM, there is a decrease in the relative contribution from vOi. Conversely, the value of K'is for BPQ remains constant when the FPP concentration is changed, showing noncompetitive kinetics with respect to this substrate. Possible causes of the observed kinetics are discussed. Inhibition by BPQ is said to follow tight binding kinetics because the value of K'is is similar to the concentration of inhibitor binding sites. Thus, to avoid an artefactual variation in potency when the enzyme concentration is varied, it is necessary to allow for the effects of depletion of free inhibitor. Furthermore, estimates of potency that average activity across the two phases are influenced by the relative contributions of each phase. These contributions differ according to the FPP concentration and the species used as the source of microsomes. Thus, it is necessary to separate the phases to compare measurements made in different experiments. Our observations indicate that careful experimental design and data analysis are required to characterise the kinetics of SQS inhibitors.


Subject(s)
Enzyme Inhibitors/pharmacology , Farnesyl-Diphosphate Farnesyltransferase/antagonists & inhibitors , Quinuclidines/pharmacology , Animals , Binding Sites , Callithrix , Dose-Response Relationship, Drug , Enzyme Inhibitors/metabolism , Enzyme Inhibitors/pharmacokinetics , Farnesyl-Diphosphate Farnesyltransferase/metabolism , Humans , Kinetics , Microsomes, Liver/enzymology , Quinuclidines/metabolism , Quinuclidines/pharmacokinetics , Rats , Sensitivity and Specificity
7.
J Rheumatol ; 18(10): 1573-80, 1991 Oct.
Article in English | MEDLINE | ID: mdl-1765984

ABSTRACT

Recent evidence suggests that pharmacological treatment may alter the rate of progression of cartilage damage in osteoarthritis (OA). However, a lack of accurate and precise noninvasive assessments of cartilage structure makes it difficult to answer this question directly with prospective clinical trials, prevents early diagnosis of OA and restricts assessment of treatment to evaluation of symptoms or joint function. It is important, therefore, to develop precise, noninvasive methods both for diagnosis of early OA before damage is extensive and irreversible and for evaluation of therapeutic effectiveness. Magnetic resonance imaging (MRI) allows for noninvasive, multiplanar body imaging which depends on proton density, flow, and the T1 and T2 relaxation times. Because these variables differ markedly among joint tissues, cartilage erosions are visible with MRI and it should be possible to quantify them. Our objective was to compare MRI with arthroscopy for assessing the depth of lesions in the articular cartilage of human knees to help develop and validate MRI for use in clinical trials designed to assess the effect of therapy on cartilage structure. In the first part of our study, the effect of the MRI pulse sequence variables on the images was evaluated by varying them systematically and comparing the anatomy seen with MRI with that seen at arthroscopy or arthrotomy and with the histology. In the second part, 31 patients were assessed with MRI before arthroscopy. The MRI were graded on a 4-point ordinal scale by 2 observers who were unaware of the clinical diagnosis and compared with findings at arthroscopy which were graded using the same scale.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Cartilage Diseases/diagnosis , Cartilage/pathology , Arthroscopy , Cartilage Diseases/pathology , Humans , Magnetic Resonance Imaging/standards , Osteoarthritis/diagnosis , Osteoarthritis/pathology
8.
Biochim Biophys Acta ; 1078(2): 251-7, 1991 Jun 24.
Article in English | MEDLINE | ID: mdl-2065092

ABSTRACT

Arylsulfatase C and steroid sulfatase were thought to be identical enzymes. However, recent evidence showed that human arylsulfatase C consists of two isozymes, s and f. In this study, the biochemical properties of the s form partially purified from human placenta were compared with those of the f form from human liver. Only the placental s form has steroid sulfatase activity and hydrolyses estrone sulfate, dehydroepiandrosterone sulfate and cholesterol sulfate. The liver f form has barely detectable activity towards these sterol sulfates. With the artificial substrate, 4-methylumbelliferyl sulfate, both forms demonstrated a similar KM but the liver enzyme has a pH optimum of 6.9 while the placental form displayed two optima at 7.3 and 5.5. The molecular weight of the native enzyme determined with gel filtration was 183,000 for the s form and 200,000 for the f form and their pI's were also similar at 6.5. However, the T50, temperature at which half of the enzyme activity was lost, was 49.5 degrees C for the f form and 56.8 degrees C for the s form. Polyclonal antibodies raised against the placental form reacted specifically against the s and not the f form. They immuno-precipitated concomitantly greater than 80% of the total placental arylsulfatase C and steroid sulfatase activities while less than 20% of the liver enzyme was immuno-precipitable. In conclusion, the two isozymes s and f of arylsulfatase C in humans purified from placenta and liver, respectively, have similar KM, pI' and native molecular weight. However, they are distinct proteins with different substrate specificity, pH optima, heat-lability and antigenic properties. Only the s form is confirmed to be steroid sulfatase.


Subject(s)
Arylsulfatases/metabolism , Isoenzymes/metabolism , Liver/enzymology , Placenta/enzymology , Arylsulfatases/chemistry , Arylsulfatases/isolation & purification , Electrophoresis, Cellulose Acetate , Humans , Molecular Structure , Precipitin Tests , Steryl-Sulfatase
9.
Am J Hum Genet ; 46(4): 729-37, 1990 Apr.
Article in English | MEDLINE | ID: mdl-1690506

ABSTRACT

Arylsulfatase C is a microsomal membrane-bound enzyme previously thought to be the same as steroid sulfatase, the only X-linked enzyme known to escape from X inactivation in man. We had shown that arylsulfatase C actually consists of two biochemically distinct isozymes, s and f. Only the s form has steroid sulfatase activity. The f and s forms were thought to be related through posttranslational or posttranscriptional modification of the same gene product. In part consistent with this hypothesis, we now report that in a panel of 28 rodent-human somatic cell hybrids, expression of both s and f was concordant only with the human X chromosome, thus showing that the f form is also X linked. In three separate somatic hybrids containing human X chromosomes in an inactive state, the f form was still expressed. Thus, similar to the s form, the f form also escapes from X inactivation. However, contrary to expectations, the s and f forms were not related by posttranslational modification of the same gene product. A full-length cDNA for the s form failed to hybridize to transcripts produced from an f-expressing cell line, showing that there is little sequence identity between the two. They are also not related by differential splicing of a common primary transcript, since fibroblasts from some patients with steroid sulfatase deficiency due to gene deletion of the s form continue to express the f form. Therefore, although the f and s isozymes of arylsulfatase C are X linked and escape from X inactivation, they are products from separate genes, thus providing a unique isoenzyme system to study possible gene duplication and regulation in the part of the human X chromosome that escapes inactivation.


Subject(s)
Arylsulfatases/genetics , Dosage Compensation, Genetic , Genetic Linkage , Isoenzymes/genetics , Sulfatases/genetics , X Chromosome , Animals , Blotting, Northern , Chromosome Mapping , DNA/genetics , DNA Probes , Fibroblasts , Gene Expression , Humans , Hybrid Cells , Ichthyosis/enzymology , Ichthyosis/genetics , Mice , RNA/genetics , Steryl-Sulfatase
10.
Arthroscopy ; 5(4): 274-81, 1989.
Article in English | MEDLINE | ID: mdl-2590325

ABSTRACT

A retrospective analysis was performed on 32 knees in 31 patients with the diagnosis of cyst of the lateral meniscus. Average follow-up was 41 months, with a range of 16-72 months. Surgical and histological examination demonstrated pathology varying from large meniscal tears with minimal cyst formation to large cysts with no demonstrable meniscal tear. Two theories of etiology emerged: (a) The tear begins in the meniscus and spreads through the periphery. (b) The lesion begins as a compression injury to the vascular periphery and spreads centrally, producing a meniscus tear, or peripherally, producing a cyst, or both. In our series, 20 patients managed by arthroscopic partial meniscectomy and open cystectomy had 80% excellent-good results versus 50% excellent-good results in 12 patients treated with arthroscopy and partial meniscectomy without extraarticular cystectomy. We recommend the following treatment: arthroscopy with a diligent search for a lateral meniscal tear, especially peripherally. If none is found, proceed to extraarticular cystectomy. If a tear is found, remove all unstable meniscal fragments, leaving a rim, if possible, especially adjacent to the popliteus recess, and then proceed to open cystectomy.


Subject(s)
Cysts/surgery , Knee Joint/surgery , Menisci, Tibial/pathology , Arthroscopy , Cysts/pathology , Follow-Up Studies , Humans , Retrospective Studies , Time Factors
11.
Pediatrics ; 81(6): 857-65, 1988 Jun.
Article in English | MEDLINE | ID: mdl-2966926

ABSTRACT

In 1984, the Committee on Sports Medicine of the American Academy of Pediatrics published in this journal a statement on the remarkably high incidence of atlantoaxial instability among individuals with Down syndrome. On the assumption that this instability, demonstrable through a specified series of lateral x-ray films of the neck, constituted a predisposition to cervical spine dislocation with subsequent spinal cord compression, the Academy supported and made more specific a series of recommendations that had originated from the Kennedy Foundation a year previously. In essence, for those persons who are found to have the radiographic sign of instability, participation in sports should be restricted. Because the implementation of these recommendations could deprive tens of thousands of individuals with Down syndrome of activities that are emotionally and physically beneficial and because of the rarity of reported cervical dislocations associated with injury, a case review was done. Included were those cases cited as support for the recommendations along with additional reports that had been omitted and a few cases reported subsequently. Little support for the hypothesis that atlantoaxial "instability" is a predisposing factor to "dislocation" was found, although much was found to indicate an urgent need for carefully designed longitudinal studies. Because nearly all of the cases of actual dislocation were preceded by at least several weeks of readily detectable physical signs, a physical examination with careful attention to neurologic signs prior to participation in sports is more predictive of potential or impending dislocation than the radiologic criteria currently recommended.


Subject(s)
Atlanto-Axial Joint , Down Syndrome/complications , Joint Instability/epidemiology , Atlanto-Axial Joint/injuries , Female , Humans , Joint Dislocations/etiology , Joint Instability/complications , Male , Risk Factors , Sports
13.
Am J Med Genet ; 28(3): 619-24, 1987 Nov.
Article in English | MEDLINE | ID: mdl-3122570

ABSTRACT

Lissencephaly, hydrocephalus, and eye abnormalities characterize patients with the Walker-Warburg syndrome, an uncommon autosomal recessive condition. Encephaloceles occur in about 50% of patients. We describe the prenatal diagnosis of this condition based on the ultrasonographic findings of retinal detachment, hydrocephalus, and an encephalocele in a fetus not known to be at risk.


Subject(s)
Abnormalities, Multiple/diagnosis , Encephalocele/diagnosis , Eye Abnormalities , Fetal Diseases/diagnosis , Hydrocephalus/diagnosis , Prenatal Diagnosis , Retinal Detachment/diagnosis , Abnormalities, Multiple/genetics , Encephalocele/genetics , Female , Fetal Diseases/genetics , Genes, Recessive , Humans , Hydrocephalus/genetics , Infant, Newborn , Pregnancy , Retinal Detachment/genetics , Syndrome , Ultrasonography
14.
Am J Med Genet ; 27(4): 799-805, 1987 Aug.
Article in English | MEDLINE | ID: mdl-3321990

ABSTRACT

Schwartz-Jampel syndrome generally presents in childhood with short stature, limited joint mobility, masklike facies with blepharophimosis, myotonia, and often muscle hypertrophy. Few cases with neonatal manifestations have been described. A newborn with severe manifestations is reported and the literature is reviewed.


Subject(s)
Microstomia/diagnostic imaging , Mouth Diseases/diagnostic imaging , Muscles/abnormalities , Osteochondrodysplasias/diagnostic imaging , Electromyography , Humans , Infant, Newborn , Male , Muscle Hypertonia/physiopathology , Radiography , Respiratory Insufficiency/physiopathology
15.
CMAJ ; 136(12): 1247, 1987 Jun 15.
Article in English | MEDLINE | ID: mdl-2438024
17.
J Biol Chem ; 261(31): 14443-7, 1986 Nov 05.
Article in English | MEDLINE | ID: mdl-3464600

ABSTRACT

When arylsulfatase C, a microsomal membrane-bound enzyme, is assayed with its natural substrates, the 3-beta-hydroxysteroid sulfates, it is also known as steroid sulfatase. Whether arylsulfatase C and steroid sulfatase are identical enzymes or not, however, has long been disputed. We now report that two electrophoretic variants of arylsulfatase C occur in normal human fibroblasts: one has a single anodic band of activity, "s," and the other has an additional faster migrating band, "f". The two types, s and "f + s", occur in cells from either sex. When fibroblast strains with the f + s forms of arylsulfatase C were cloned, two types of primary clones were always obtained: s and f + s. A single f band was never seen. When these primary clones were subcloned, however, the arylsulfatase C phenotype remained unchanged: primary s clones gave rise to s subclones and f + s clones to f + s subclones only. Therefore, these forms were clonal in origin and demonstrated a novel inheritance pattern in human cultured cells. The appearance of increasing amounts of the f band was correlated with up to 4-fold increase of arylsulfatase C activity, whereas the steroid sulfatase activity remained constant, thus demonstrating that arylsulfatase C was not identical with steroid sulfatase activity. Polyclonal antibodies raised against the s form immunoprecipitated activities of the s form of arylsulfatase C and steroid sulfatase but not the f form of arylsulfatase C. Therefore, we conclude that only the s form of arylsulfatase C is immunologically related to steroid sulfatase so that arylsulfatase C per se is not necessarily identical with steroid sulfatase. In addition, a novel form of genetic heterogeneity of isozymes in human fibroblasts is demonstrated.


Subject(s)
Arylsulfatases/metabolism , Isoenzymes/metabolism , Sulfatases/metabolism , Antigen-Antibody Complex , Arylsulfatases/isolation & purification , Cells, Cultured , Clone Cells/enzymology , Female , Fibroblasts/enzymology , Humans , Immune Sera , Isoenzymes/isolation & purification , Kinetics , Male , Skin/enzymology , Steryl-Sulfatase , Sulfatases/isolation & purification
18.
Am J Med Genet ; 25(2): 205-10, 1986 Oct.
Article in English | MEDLINE | ID: mdl-3535500

ABSTRACT

A female infant with Kaufman-McKusick syndrome redeveloped respiratory distress and abdominal distention at 5 weeks of age. Ultrasonography demonstrated recurrence of peritoneal cysts and hydrometrocolpos. It is postulated that refluxing vaginal secretions may contribute to the abdominal distention seen in many infants with Kaufman-McKusick syndrome.


Subject(s)
Abdomen/pathology , Abnormalities, Multiple/diagnosis , Abnormalities, Multiple/genetics , Abnormalities, Multiple/surgery , Cysts/congenital , Drainage , Female , Fingers/abnormalities , Humans , Infant, Newborn , Peritoneal Diseases/congenital , Syndrome , Ultrasonography , Uterus/abnormalities , Vagina/abnormalities
19.
Int J Sports Med ; 6(6): 314-6, 1985 Dec.
Article in English | MEDLINE | ID: mdl-4077357

ABSTRACT

This study surveyed 76 female basketball-related injuries that occurred during a 30-month period at the B.C. Sports Medicine Clinic. The knee was the most common site of injury (72%), and anterior cruciate ligament (ACL) rupture accounted for 25% of all basketball injuries seen. A total of 19 ACL ruptures in females were seen as compared to only 4 ACL ruptures in male basketball players during the same time period. During this time period a total of 151 males and 76 female basketball players were seen. Each patient was assessed as to age, height, weight, and alignment and questioned as to mechanism of injury, playing position, experience, and training plus previous injuries. Possible etiological factors postulated included player position, joint laxity, weak quadriceps mechanism, and a possible hormonal basis.


Subject(s)
Athletic Injuries/physiopathology , Knee Injuries/physiopathology , Ligaments, Articular/injuries , Adolescent , Female , Humans , Sex Factors , Sports Medicine
20.
Anal Biochem ; 144(2): 362-70, 1985 Feb 01.
Article in English | MEDLINE | ID: mdl-3857872

ABSTRACT

Arylsulfatase-C is a microsomal membrane-bound enzyme with unusual biochemical and genetic properties. Whether it is a single enzyme hydrolyzing different sterol sulfates or a complex of enzymes, with each enzyme hydrolyzing a specific substrate, has not been resolved. Its locus has been mapped to the human X chromosome but appears to escape inactivation. As a first step to clarify its biochemical properties, a systematic search was undertaken for a suitable detergent that can release this enzyme from human cultured fibroblast membranes in a form that is biologically active and electrophoretically mobile. Four non ionic (Triton X-100, Nonidet P-40, Digitonin, and saponin) and four amphoteric (lysolecithin, Zwittergent, Miranol, and Chaps) detergents were studied. At 1% concentration, they released more than 80% of the activity into a low-speed supernatant fraction, except for Saponin which had no effect. With Triton X-100 and Miranol representing the two groups of detergents, significant release occurred only when the detergent concentrations exceeded their respective critical micelle concentrations, thus indicating that arylsulfatase-C is an integral membrane protein. The apparent molecular weight of the detergent-enzyme complex, ascertained by gel filtration, was 85,000 in the presence of Triton X-100 and 335,000 in the presence of Miranol. However, only the preparation solubilized by Miranol (and Chaps, to a lesser degree) permitted migration of the enzyme in nitrocellulose acetate during electrophoresis at pH 7.0, while the enzyme extracted with all other detergents remained at the origin. Therefore, the amphoteric detergent, Miranol, appears to fulfill the requirements for further characterization of the membrane-bound arylsulfatase-C in human cultured fibroblasts.


Subject(s)
Arylsulfatases/isolation & purification , Sulfatases/isolation & purification , Surface-Active Agents , Cell Membrane/enzymology , Cells, Cultured , Fibroblasts/enzymology , Humans , Hydrogen-Ion Concentration , Molecular Weight , Proteins/analysis , Solubility , Steryl-Sulfatase
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