Prevalence and associated factors of non-traumatic knee pain in high school volleyball players: a cross-sectional study.

OBJECTIVES: This study aimed to determine the prevalence of knee pain among high school volleyball attackers, identify associated factors, and explore the relationship between knee pain and lower back pain (LBP). METHODS: A cross-sectional study involving 82 high school volleyball attackers (15-17 years) used questionnaires, interviews, and field-based assessments to collect data on demographics, volleyball-specific factors, flexibility, and jumping ability. Logistic regression analysis was used to identify factors associated with knee pain. RESULTS: The prevalence of knee pain was 19.5%. Factors significantly associated with knee pain were a history of LBP (OR, 4.64; 95% CI, 1.28 to 16.8; p = 0.019) and flexibility determined by the absolute difference in heel-buttock distance (OR, 1.37; 95% CI, 1.02 to 1.83; p = 0.037). Participants with knee pain had more volleyball experience and a higher proportion of players who competed as starters in the previous year. Both groups reported approximately 18 hours of practice per week during the school year and around 27 hours during school holidays, with no significant difference observed. CONCLUSION: Factors associated with knee pain include a history of LBP and reduced flexibility on the heel-buttock distance test. The study highlights the need for a comprehensive approach, considering the coexistence of LBP and focusing on improving anterior thigh flexibility.

Prevalence of Glenohumeral Internal Rotation Deficit and Sex Differences in Range of Motion of Adolescent Volleyball Players: A Case-Control Study.

Shoulder range of motion (ROM) adaptation is common observed among volleyball players, but studies on the shoulder joint function of adolescent athletes are lacking. This study aimed to clarify the prevalence of glenohumeral internal rotation deficit (GIRD) among adolescent players and differences in ROM based on sex. A questionnaire survey and ROM measurements of the shoulder joint and trunk using a plastic goniometer were conducted on 123 volleyball players (63 males and 60 females; mean age, 15.8 years). The prevalence of GIRD was investigated for internal rotation differences of >10° and total rotation motion of <5°. Questionnaire items and ROM were compared between GIRD and non-GIRD patients, and sex differences in ROM were also presented. Of the participants, 38.2% (n = 47/123) had GIRD. The GIRD group showed a decrease in external rotation on the dominant side (p = 0.003, 1 − beta = 0.84), but this was not associated with a history of shoulder injury. Sex differences in shoulder ROM showed hypomobility in males and hypermobility in females. However, there was no association between shoulder injury and GIRD among adolescent players. There are sex differences in ROM, which should be considered in future studies.

Efficacy of semi-customized exercises in preventing low back pain in high school volleyball players: A randomized controlled trial.

BACKGROUND: Low back pain (LBP) is a common injury in high school volleyball players. We hypothesized that a prevention program could decrease the incidence of LBP in high school volleyball players. This study was an in-season cluster-randomized controlled trial. METHODS: We block-randomized 8 high school volleyball teams comprising 70 players aged 15 to 17 years into the intervention (4 teams, 34 players) and control (4 teams, 36 players) groups. The intervention program consisted of 9 physical function tests as well as 1 or 2 self-selected preventive exercises, including dynamic thoracic mobility, trunk stabilization exercises, and static stretching, performed during warm-up. Both groups were followed up for 4 weeks, during which the incidence of LBP was recorded. Physical function tests (back endurance; spinal and back flexibility; active or passive shoulder and trunk range of motion; ankle joint mobility; and iliopsoas, quadriceps, and hamstrings flexibility) were conducted before and after the intervention. RESULTS: The intervention group had a significantly lower incidence of LBP (8.8%) than the control group (33.3%) (relative risk, 3.78; 95% confidence interval, 1.17-12.23; P = .017, 1 - ß = 0.99). Lumbar extension accounted for nearly 70% of LBP incidences. Most players in the intervention group demonstrated improved physical function associated with the exercises. CONCLUSION: The semi-customized prevention program decreased the incidence of LBP and enhanced the physical function parameter in high school volleyball players.

Sexual Difference in the Optimum Environmental Conditions for Growth and Maturation of the Brown Alga Undaria pinnatifida in the Gametophyte Stage.

Undaria pinnatifida is an annual brown kelp growing naturally in coastal areas as a major primary producer in temperate regions and is cultivated on an industrial scale. Kelps have a heteromorphic life cycle characterized by a macroscopic sporophyte and microscopic sexual gametophytes. The sex-dependent effects of different environmental factors on the growth and maturation characteristics of the gametophyte stage were investigated using response surface methodology. Gametophytes were taken from three sites in Japan: Iwate Prefecture, Tokushima Prefecture, and Kagoshima Prefecture in order to confirm the sexual differences in three independent lines. Optimum temperature and light intensity were higher for males (20.7-20.9 °C and 28.6-33.7 µmol m-2 s-1, respectively) than females (16.5-19.8 °C and 26.9-32.5 µmol m-2 s-1), and maturity progressed more quickly in males than females. Optimum wavelengths of light for growth and maturation of the gametophytes were observed for both blue (400-500 nm, λmax 453 nm) and green (500-600 nm; λmax 525 nm) lights and were sex-independent. These characteristics were consistent among the three regional lines. Slower growth optima and progress of maturation could be important for female gametophytes to restrict fertilization and sporophyte germination to the lower water temperatures of autumn and winter, and suggest that the female gametophyte may be more sensitive to temperature than the male. The sexual differences in sensitivity to environmental factors improved the synchronicity of sporeling production.

[Design, synthesis, and structure-activity relationship study of organoantimony compounds that induce the expression of perlecan in vascular endothelial cells].

  Organometallic compounds and complexes possibly show novel bioactivities unprecedented with organic molecules that consist of C, H, O, and N atoms. We have already reported that an organoantimony compound selectively induces the expression of perlecan, a large heparin sulfate proteoglycan, in cultured vascular endothelial cells. Perlecan consists of a core protein with Mr of approximately 400 kDa and three anticoagulant heparan sulfate glycosaminoglycan chains. However, little is known about the molecular mechanisms of perlecan expression in endothelial cells. Since an organoantimony compound induces the expression of perlecan, we prepared a variety of its derivatives and tried to identify the binding proteins for the organoantimony compound by the drug affinity responsive target stability method, a negative selection method to identify the target proteins. As the results, we found glucocoriticoid receptor as binding protein of the organoantimony compound, which mediates the expression of perlecan in endothelial cells.

Successful in vivo propagation of factor IX-producing hepatocytes in mice: potential for cell-based therapy in haemophilia B.

Cell-based therapies using isolated hepatocytes have been proposed to be an attractive application in the treatment of haemophilia B due to the normal production of coagulation factor IX (FIX) in these particular cells. Current cell culture technologies have largely failed to provide adequate isolated hepatocytes, so the present studies were designed to examine a new approach to efficiently proliferate hepatocytes that can retain normal biological function, including the ability to synthesize coagulation factors like FIX. Canine or human primary hepatocytes were transplanted into urokinase-type plasminogen activator-severe combined immunodeficiency (uPA/SCID) transgenic mice. Both donor hepatocytes from canines and humans were found to progressively proliferate in the recipient mouse livers as evidenced by a sharp increase in the circulating blood levels of species-specific albumin, which was correlated with the production and release of canine and human FIX antigen levels into the plasma. Histological examination confirmed that the transplanted canine and human hepatocytes were able to proliferate and occupy >80% of the host livers. In addition, the transplanted hepatocytes demonstrated strong cytoplasmic staining for human FIX, and the secreted coagulation factor IX was found to be haemostatically competent using specific procoagulant assays. In all, the results from the present study indicated that developments based on this technology could provide sufficient FIX-producing hepatocytes for cell-based therapy for haemophilia B.

Factor VIII-mediated global hemostasis in the absence of von Willebrand factor.

Although the efficacy of recombinant factor VIII (rFVIII) in the treatment of type 3 von Willebrand disease (VWD) has been reported, the mechanisms by which FVIII concentrates devoid of von Willebrand factor (VWF) induce improvements in hemostasis are poorly understood. To address the role of FVIII or intrinsic coagulation in the absence of VWF, we performed a hemostatic analysis. Blood samples were obtained before and after the administration of rFVIII to 2 patients with type 3 VWD. A rotating thromboelastometry assay was performed to examine global interactions in hemostasis. Studies of thrombin-and shear-induced platelet aggregation were also conducted to elucidate the effect on platelet activation. Furthermore, we assessed the rise in the thrombin-induced intracellular concentration of free calcium [Ca2+]i. Addition of rFVIII to preinfusion blood in vitro corrected thromboelastometric parameters and thrombin-induced aggregation. In ex vivo studies, thromboelastometry analysis showed that rFVIII shortened the onset and progression of the coagulation process. Furthermore, rFVIII corrected low shear-induced and thrombin-induced platelet aggregation in platelet-rich plasma. In addition, rFVIII improved thrombin-induced [Ca2+]i flux in washed platelets. Our observations suggested that FVIII is incorporated into platelets to activate them, as well as to act directly in intrinsic coagulation in the absence of VWF. FVIII may play a critical role even in the absence of VWF.

Phenotype correction of hemophilia A mice with adeno-associated virus vectors carrying the B domain-deleted canine factor VIII gene.

Adeno-associated virus (AAV) vectors carrying the B domain-deleted canine FVIII (BDD cFVIII) gene utilizing the beta-actin minimum promoter (167b) pseudotyped with serotype 1 (AAV1-beta-actin-cFVIII) and serotype 8 (AAV8-beta-actin-cFVIII) were developed to express cFVIII in hemophilia A mice. FVIII clotting activities measured by the APTT method increased in hemophilia A mice with intramuscular injection of AAV1-beta-actin-cFVIII in a dose-dependent manner. Therapeutic FVIII levels (2.9+/-1.0%) in hemophilia A mice with the AAV1-beta-actin-cFVIII dose of 1 x 10(12) gc/body were achieved, suggesting partial correction of the phenotype with AAV1-beta-actin-cFVIII vectors. FVIII clotting activity levels in hemophilia A mice with intravenous injection of AAV8-beta-actin-cFVIII also were increased dose-dependently, achieving therapeutic FVIII levels (5-90%) in hemophilia A mice with the AAV8-beta-actin-cFVIII doses of 1-3 x 10(11) gc/body and supernormal FVIII levels (180-670%) in hemophilia A mice with the AAV8-beta-actin-cFVIII dose of 1 x 10(12) gc/body. Transduction of the liver with AAV8-beta-actin-cFVIII is superior to transduction of skeletal muscles with AAV1cFVIII regarding the FVIII production and antibody formation. These data suggested that both AAV1 and AAV8 vectors carrying the FVIII gene utilizing a minimum promoter have a potential for hemophilia A gene therapy.

Liver tissue engineering at extrahepatic sites in mice as a potential new therapy for genetic liver diseases.

Liver tissue engineering using hepatocyte transplantation has been proposed as an alternative to whole-organ transplantation or liver-directed gene therapy to correct various types of hepatic insufficiency. Hepatocytes are not sustained when transplanted under the kidney capsule of syngeneic mice. However, when we transplanted hepatocytes with the extracellular matrix components extracted from Engelbreth-Holm-Swarm cells, hepatocytes survived for at least 140 days and formed small liver tissues. Liver engineering in hemophilia A mice reconstituted 5% to 10% of normal clotting activity, enough to reduce the bleeding time and have a therapeutic benefit. Conversely, the subcutaneous space did not support the persistent survival of hepatocytes with Engelbreth-Holm-Swarm gel matrix. We hypothesized that establishing a local vascular network at the transplantation site would reduce graft loss. To test this idea, we provided a potent angiogenic agent before hepatocyte transplantation into the subcutaneous space. With this procedure, persistent survival was achieved for the length of the experiment (120 days). To establish that these engineered liver tissues also retained their native regeneration potential in vivo, we induced two different modes of proliferative stimulus to the naive liver and confirmed that hepatocytes within the extrahepatic tissues regenerated with activity similar to that of naive liver. In conclusion, our studies indicate that liver tissues can be engineered and maintained at extrahepatic sites, retain their capacity for regeneration in vivo, and used to successfully treat genetic disorders.

Up-regulation of interleukin-2 mRNA in children with idiopathic nephrotic syndrome.

The current hypothesis for the pathogenesis of childhood idiopathic nephrotic syndrome (INS) favors the involvement of a T cell-mediated immune response. Various cytokines derived from T cells may play a critical role in INS. Previous studies have measured serum or urine cytokine levels and suggest an imbalance of the T cell-mediated immune response. To elucidate the true profile of T cell-derived cytokines, we determined interleukin (IL)-2, interferon (IFN)-gamma, IL-4, IL-10, and tumor necrosis factor (TNF)-alpha mRNA expression in children with INS. We collected mRNA from peripheral blood mononuclear cells together with plasma and urine from nine children in the acute and remission phases of INS. Expression of IL-2, IFN-gamma, IL-4, IL-10, and TNF-alpha mRNA was determined by a quantitative real-time PCR assay. Plasma and urine cytokine concentrations were measured using a specific enzyme-linked immunosorbent assay. These data were compared between the acute and remission phase in the same patients. The IL-2 mRNA levels were significantly higher in the acute phase than in the remission phase, whilst no significant difference was found in the other cytokines investigated. There was no significant difference in the plasma and urine cytokine concentrations between the acute and remission phase. Our results indicate increased expression of IL-2 mRNA in the acute phase of INS, suggesting that IL-2, at least in part, might be involved in the pathophysiology of childhood INS.

Inversions of the factor VIII gene in Japanese patients with severe hemophilia A.

Hemophilia A is genetically very heterogeneous because disease-causing mutations involving deletions, point mutations, insertions, and inversions are scattered throughout the factor VIII gene. Of these mutations, inversions, which are intrachromosomal recombinations between int22h-1 (intron 22 homologous region 1) and 1 of 2 other extragenic copies located 500 kilobases upstream, are the more frequently found defects, especially in patients with severe hemophilia A. Reportedly, approximately half of all severe hemophilia A patients have inversions in intron 22. A group of unrelated patients from the middle of Japan with severe hemophilia A were screened by Southern blot analysis for gene inversions. Forty-two of 100 severely affected patients presented factor VIII gene rearrangements. Of these patients, 36 exhibited the distal type of inversion, and 6 exhibited the proximal type. No other variant type of recombination was observed. In this study, neither the prevalence of inhibitor development against factor VIII nor the frequency of sporadic cases in the group presenting gene inversions was significantly different from that in the group without chromosomal inversions. Southern blot analysis successfully detected a carrier in a hemophilia family for which no patient was available. Genetic counseling of patients with severe hemophilia A and their families will be considerably improved, because the inversions occur in 42% of the Japanese patients with severe hemophilia.

A girl with bilateral ovarian tumours: Frasier syndrome.

UNLABELLED: Frasier syndrome (FS) is characterised by male pseudohermaphroditism, slowly progressing nephropathy and frequent development of gonadoblastoma. The Wilms' tumour suppressor gene (WT1 gene) plays an important role in the development of the urogenital system and the gonads. A splice mutation in intron 9 of the WT1 gene was recently described in patients with FS. We analysed the WT1 gene of a Japanese patient with male pseudohermaphroditism, steroid resistant-nephr-opathy and gonadoblastoma by the polymerase chain reaction and direct sequencing and detected a heterozygous point mutation in intron 9. CONCLUSION: analysis of the Wilms' tumour suppressor gene in a patient with Frasier syndrome by the polymerase chain reaction and direct sequencing detected a + 5G -->A transition at a position of the second alternative splice region of exon 9, important for predicting the risk of the occurrence of Wilms' tumour.