Focus Issue on Male Infertility

Male infertility problems can occur when sperms are limited in number or function. In this paper, we describe the clinical evaluation of male infertility. A detailed history, physical examination, and basic semen analysis are required. In addition, ultrasound, karyotyping, and hormonal studies are needed to determine specific causes of infertility. In addition, the World Health Organization (WHO, 2009) has developed a manual to provide guidance in performing a comprehensive semen analysis. Among the possible reasons for male infertility, nonobstructive azoospermia is the least treatable, because few or no mature sperm may be produced. In many cases, men with nonobstructive azoospermia typically have small-volume testes and elevated FSH. Although treatment may not completely restore the quality of semen from men with subnormal fertility, in some cases a successful pregnancy can still be achieved through assisted reproductive technology

QUANTITATIVE EVALATION OF DEXTERITY BY MODELING OF JOINT TORQUE

The aim of this study is to quantitatively evaluate the stretch reflex on athletic motions. In this study, we regard stretch reflex as an index of dexterity because dexterous motions effectively utilize the stretch reflex by relaxing the stiffness of articulations. Subjects were one skilled and one unskilled. They performed power clean that is a typical strength training motion. We measured trajectories of joints by using the motion capture system, numerically filtered, differentiated, and calculated the articulation torques. In order to evaluate the strength of stretch reflex, we employ a time series curve fitting method in the proposed torque model that includes a term caused by stretch reflex. The results indicate that the skilleds’ strength of stretch reflex shows large value, compared to the unskilled’s one. This suggests that the proposed torque model and the analytic method allow us to quantitatively measure dexterity

Applicability Test of Soil Improvement Using Micro-Bubbles Against Soil Liquefaction

The purpose of this paper is to demonstrate the effectiveness of micro-bubble water injection method against soil liquefaction based on the result of seismic vibration test using large scale flexible shaking box. It is well known that soil resistance to liquefaction increases as the degree of saturation of the soil decreases, but the practical method to decrease the saturation of the soil has not been invented. The authors solved this problem by new method of injecting water containing micro-air bubbles into the ground. The method has an advantage which not only simple and cost-effective but also friendly to environment. We examined two cases, which are micro-bubble water injected sand ground and degassed water injected one, to compare the behavior of anti-liquefaction in the large scale test ground soil. As the result, it was observed that liquefaction did not occur even at maximum acceleration level of 200Gal under the condition of lowered saturation to 80% with N-value of around 7, which is loose or fragile ground. In addition, the results also could be suggested that the possibility of brand new method of “seismic avoid ground” with hybrid layered ground of air injected soil around housing foundations and liquefaction soil under the ground

A CONSIDERATION OF QUANTITATIVE EVALUATION OF DEXTERITY IN SPORTS EXERCISE

The aim of this study was to quantitatively evaluate dexterity on athletic motions. Subjects were three skilled and three non-skilled weight lifters. They performed power clean that is a strength-training motion. We measured trajectories of joints by using motion capture system, and calculated joint torque according to dynamical equations using only kinematic data. In order to evaluate the strength of stretch reflex and that of proprioceptive feedbacks, we employed curve fitting with the recursive least squares method in our proposed torque model that includes a term caused by stretch reflex and feedback terms with respect to the COP and COM position. The results show that the calculated coefficients reflect some dexterous behavior of skilled motions

STUDY OF THE MECHANISM OF EXPLOSIVE FORCE PRODUCTION ON QUICK LIFT MOTION BY ANALYSIS OF EMG AND MOTION

The aim of this study is to investigate how explosive force exerts during power clean (PC) motion. The subjects are ten skilleds and ten unskilleds. The joint trajectory and EMG during PC are recorded. The joint torque and its rate of torque development (RTD) are calculated from the obtained data. The joint stiffness is estimated from joint stiffness index (JSI) calculated from EMG of agonist and antagonist muscle pair. Experimental results indicated that the skilleds showed the double knee bent that is typically seen in a stretch-shortening cycle (SSC). Skilleds exerted large values of RTD and JSI just after a period of exerting their small values during SSC. It indicates that a much amount of elastic energy stored in a low stiffness state is instantly transferred to the upper segments in the successive high stiffness state by “tenodesis action” of muscles. This is why large RTD generates in the skilled

Molecular dynamics study of free energy profile for dissociation of ligand from CA I active site

We investigate the binding/dissociation process of ligand molecule from carbonicanhydrase (CA) I carbonic anhydrase (CA) I enzyme by using all-atom moleculardynamics simulation. The force field parameters of zinc ion in the CA I active site are estimatedby quantum chemical calculations and are summarized in this paper. The free energyprofile for binding/dissociation process of ligand from CA I active site is calculated by thethermodynamic integration combined with the all-atom molecular dynamics simulation. Thebinding free energy as a function of the distance between the center of mass positions of CAI active site and the ligand molecule is estimated. The radial distribution function of theCA I-ligand complex is calculated from the trajectory of all-atom molecular dynamics (MD)simulation. We estimate the free energy surface from the radial distribution function. Wecan obtain the bond constant of the equilibrium state from the value of the free energy surface.We discuss the binding/dissociation process of ligand molecule by calculating the freeenergy profile to know the stability of the CA I-ligand complex with some thermodynamicproperties such as the binding free energy, the equilibrium state of the free energy surfaceand so on

Combination of C-reactive protein/albumin ratio and time to castration resistance enhances prediction of prognosis for patients with metastatic castration-resistant prostate cancer

ObjectiveThis study aimed to identify the prediction accuracy of the combination of C-reactive protein (CRP) albumin ratio (CAR) and time to castration resistance (TTCR) for overall survival (OS) following development of metastatic castration-resistant prostate cancer (mCRPC).MethodsClinical data from 98 mCRPC patients treated at our institution from 2009 to 2021 were retrospectively evaluated. Optimal cutoff values for CAR and TTCR to predict lethality were generated by use of a receiver operating curve and Youden’s index. The Kaplan–Meier method and Cox proportional hazard regression models for OS were used to analyze the prognostic capabilities of CAR and TTCR. Multiple multivariate Cox models were then constructed based on univariate analysis and their accuracy was validated using the concordance index.ResultsThe optimal cutoff values for CAR at the time of mCRPC diagnosis and TTCR were 0.48 and 12 months, respectively. Kaplan–Meier curves indicated that patients with CAR >0.48 or TTCR <12 months had a significantly worse OS (both p < 0.005). Univariate analysis also identified age, hemoglobin, CRP, and performance status as candidate prognostic factors. Furthermore, a multivariate analysis model incorporating those factors and excluding CRP showed CAR and TTCR to be independent prognostic factors. This model had better prognostic accuracy as compared with that containing CRP instead of CAR. The results showed effective stratification of mCRPC patients in terms of OS based on CAR and TTCR (p < 0.0001).ConclusionAlthough further investigation is required, CAR and TTCR used in combination may more accurately predict mCRPC patient prognosis

Prognostic Impact of Number of Resected and Involved Lymph Nodes at Complete Resection on Survival in Non-small Cell Lung Cancer

BackgroundLymph node (LN) status is a major determinant of stage and survival in patients with lung cancer. In the 7th edition of the TNM Classification of Malignant Tumors, the number of involved LNs is included in the definition of pN factors in breast, stomach, esophageal, and colorectal cancer, and the pN status significantly correlates with prognosis.MethodsWe retrospectively investigated the prognostic impact of the number of resected LNs (RLNs) and involved LNs in the context of other established clinical prognostic factors, in a series of 928 consecutive patients with non-small cell lung cancer (NSCLC) who underwent complete resection at our institution between 2000 and 2007.ResultsThe mean number of RLNs was 15. There was a significant difference in the total number of RLNs categorized between less than 10 and ≥10 (p = 0.0129). Although the incidence of LN involvement was statistically associated with poor prognosis, the largest statistically significant increase in overall survival was observed between 0 to 3 and ≥4 involved LNs (hazard ratio = 7.680; 95% confidence interval = 5.051–11.655, p < 0.0001). On multivariate analysis, we used the ratio between the number of involved LNs and RLNs. The number of RLNs was found to be a strong independent prognostic factor for NSCLC (hazard ratio = 6.803; 95% confidence interval = 4.137–11.186, p < 0.0001).ConclusionComplete resection including 10 or more LNs influenced survival at complete NSCLC resection. Four involved LNs seemed to be a benchmark for NSCLC prognosis. The number of involved LNs is a strong independent prognostic factor in NSCLC, and the results of this study may provide new information for determining the N category in the next tumor, node, metastasis classification