Effect of semiconductor GaAs laser irradiation on pain perception in mice

The influence of subacute exposure (11 exposures within 16 days) of mice to the low power (GaAs) semiconductive laser-stimulated irradiation on pain perception was investigated. The pain perception was determined by the latency of foot-licking or jumping from the surface of a 53 degrees C hot plate. Repeated hot-plate testing resulted in shortening of latencies in both sham- and laser-irradiated mice. Laser treatment (wavelength, 905 nm; frequency, 256 Hz; irradiation time, 50 sec; pulse duration, 100 nsec; distance, 3 cm; peak irradiance, 50 W/cm2 in irradiated area; and total exposure, 0.41 mJ/cm2) induced further shortening of latencies, suggesting its stimulatory influence on pain perception. Administration of morphine (20 mg/kg) prolonged the latency of response to the hot plate in both sham- and laser-irradiated mice. This prolongation tended to be lesser in laser-irradiated animals. Further investigations are required to elucidate the mechanism of the observed effect of laser.     

The venous drainage of the tectum mesencephali

Summary The normal course and appearance of the veins draining the tectum mesencephali proper are described in detail on the basis of the anatomical radiological study. These specific veins, the quadrigeminal veins, were constantly present on autopsy study. There are two types of variations of these quadrigeminal veins. They have a close anatomical and angiographic correlation with the quadrigeminal plate proper, and also outline the posterior aspects of the quadrigeminal plate. The whole structure of the mesencephalon may be delineated by these veins in combination with the other veins of the mesencephalon. They may be of diagnostic value in the early recognition of the brain stem lesions.Presented at the 3rd Meeting of the Japancse Society of Neuroradiology, Tokyo, February 16, 1974, and the 33rd Annual Meeting of the Japan Neurological Society, Sendai, October 23, 1974.     

Evaluation of Euglobulin Clot Lysis Time as a Screening Method for Determination of Blood Plasma Fibrinolytic Activity after Venous Occlusion

ABSTRACT Determination of the fibrinolytic activity should be performed in patients with recurrent thromboembolic disease. As a screening procedure we suggest the euglobulin clot lysis time test after venous occlusion. This test is sufficiently reliable and easier to perform than the fibrin plate method, especially outside coagulation laboratories.     

A Study of the Efficacy of Antimicrobial Detergents for Hand Washing: Using the Full-hand Touch Plates Method

We studied the effects of four kinds of antimicrobial detergents, 4% chlorhexidine gluconate (CHG), chlorbenzarconium (CBC), 10% povidone-iodine (PVI), 0.3% triclosan (TRI), and one non-medicated detergent (NMD) using the full-hand touch plates method. Before and after 3 minutes of hand scrubbing with a brush, bacterial colonies on the hand surface and subungual bacteria were counted. CHG, CBC, and PVI were excellent antimicrobial detergents against hand surface bacteria, but most of the subungual bacteria remained. The subungual space was the most difficult region from which to eradicate bacteria. TRI was much less effective than hand soap against hand surface bacteria.     

Increased cAMP production after short-term capacitively coupled stimulation in bovine growth plate chondrocytes

Growth plate chondrocytes from newborn calf costochondral junctions grown in monolayer were subjected to a capacitive AC signal of 500 V peak to peak (P-P) at 60 kHz for 48 h and were analyzed for [3H]thymidine uptake. The stimulated chondrocytes showed a 130% greater uptake over unstimulated controls. Other newborn calf growth plate chondrocytes were stimulated at 500 V P-P at 60 kHz for 2.5, 5.0, 10.0, and 20.0 min and were analyzed for cAMP. Chondrocytes stimulated for 2.5 and 5.0 min showed a 142.8% (p less than 0.05) and 394.5% (p less than 0.01) increase over controls, respectively. The chondrocytes stimulated for 10.0 and 20.0 min showed no significant difference from the controls. It is concluded that short-term exposure of growth plate chondrocytes to an appropriate capacitively coupled field stimulates cAMP production, but longer-term application of the electrical field is ineffective.     

FAMILIAL SLIPPED CAPITAL FEMORAL EPIPHYSIS: A REPORT AND CONSIDERATIONS IN MANAGEMENT

Background : Familial inheritance of slipped capital femoral epiphysis (SCFE) is known. It has not been described in non-identical twins. A family where the mother and three of five siblings developed SCFE were investigated and managed. Methods : Anthropometric measurement consisted of height-weight ratios. Serum sex hormone levels and bone Gla Protein was measured. Bone mineral densities were evaluated. Results : The affected siblings had higher bodyweight percentiles. Other investigations were within normal limits. Conclusion : The unfavourable height-to-weight ratio was one of the mainstays in developing a management protocol for all siblings. The management protocol developed for the family is discussed.     

The role of mechanical loading histories in the development of diarthrodial joints

The possible role of mechanical loading history in chondroosseous development at the ends of long bones is explored using two-dimensional finite element models of chondroepiphyses. Loading histories are characterized in terms of discrete loading cases defined by joint contact pressure distributions and an associated number of loading cycles. An osteogenic stimulus throughout the chondroepiphyses is calculated following the theory that cyclic octahedral shear stresses promote endochondral ossification and cyclic compressive dilatational stresses inhibit ossification. The resulting distributions for the osteogenic stimulus predict the appearance of the secondary ossific nucleus and the shape of the developing bony epiphysis. The zone of Ranvier and the formation of articular cartilage and the growth plate are also predicted by the models. These findings are consistent with the hypothesis that tissue stress histories constitute an important influence during skeletal morphogenesis. Further study and testing of the concepts introduced in this study are appropriate.     

Partial purification and characterization of a proteoglycan-degrading neutral protease from bovine epiphyseal cartilage

Degradation of the proteoglycan matrix is considered an essential step in the process of calcification in the growth plate. This laboratory has just described the presence of a protease in human growth plate cartilage that degrades proteoglycan at neutral pH. We report here the isolation, partial purification, and characterization of these proteoglycan-degrading neutral proteases of bovine epiphyseal cartilage. It appears that there is more than a single enzyme active at neutral pH. These enzymes are of low molecular weight (below 30,000), poorly charged, and inhibited by metal chelating agents. Activity is best restored in the presence of zinc. This represents the first characterization of this important enzyme group.     

Stereological studies on the epiphyseal growth plate in low phosphate,vitamin D-deficiency rickets with special reference to the distribution of matrix vesicles

Summary In low phosphate, vitamin D-deficiency rickets normal mineralization is reversibly arrested, and rickets is thus a suitable model for studying factors influencing the mineralization process. Partly on the basis of their distribution within the growth cartilage, the so-called matrix vesicles are considered to play an important role in the process of mineralization and it has been claimed that the distribution pattern is the same in rickets as in normal animals. With the use of modern stereological techniques, our group recently demonstrated a matrix vesicle distribution between the zones of the epiphyseal growth plate in normal rats different from that described earlier. The same bimodal distribution pattern was observed in rachitic rats in the present study, the highest volume density being found in the resting and upper hypertrophic zones and the lowest in the proliferative zone. The volume density differences are explained by differences in the number of vesicles between zones, the variation in mean caliper diameter being small. Our findings are discussed in relation to the proposed theories on matrix vesicle origin. The results seem to support the dynamic cell debris theory for matrix vesicle origin presented earlier, but the existence of subpopulations of matrix vesicles with a specialized function and origin cannot be ruled out.     

钛板坚固内固定技术在颌骨骨折治疗中的应用

目的通过对一组颌面部骨折钛板坚固内固定治疗的回顾性分析,评估该治疗方法的可靠性及其临床效果,探讨其优缺点及手术技巧。方法 17例共计52处颌骨骨折行小(微)型钛板复位坚固内固定,术后定期复诊,根据外形、咬合关系、开口度的恢复及X光片检查骨折愈合情况确定临床效果。结果 15例创口一期愈合,2例创口感染,经局部换药后愈合;外形恢复满意,咬合关系良好,开口度接近正常,X光片检查骨折愈合良好,无骨不连接表现。结论以钛板坚固内固定技术治疗颌骨骨折临床效果可靠,可避免术后颌间结扎,较传统的复位方法(颌间结扎、钢丝拴扎固定等)有明显的优点。