Characterization of freezing of gait subtypes and the response of each to levodopa in Parkinson''s disease

To assess the effect of levodopa on distinct freezing of gait (FOG) subtypes in patients with 'off' FOG. Nineteen patients (12 men, mean age 62.0 +/- 8.4 years) with Parkinson's disease and clinically significant FOG during 'off' states were videotaped whilst walking 130 m during 'off' and 'on' states. Three independent observers characterized the type, duration, and clinical manifestations and quantified FOG by analyzing the videotapes. Their combined mean scores were used for statistical analysis. The intra-class correlation coefficient assessed inter-observer reliability. Wilcoxon and Friedman tests evaluated differences in mean frequencies of FOG characteristics. During 'off' states, FOG was elicited by turns (63%), starts (23%), walking through narrow spaces (12%) and reaching destinations (9%). These respective values were only 14, 4, 2 and 1% during 'on' states (P < 0.011). Moving forward with very small steps and leg trembling in place were the most common manifestations of FOG; total akinesia was rare. Most FOG episodes took <10 s and tended to be shorter during 'on' states. Levodopa significantly decreased FOG frequency (P < 0.0001) and the number of episodes with akinesia (P < 0.001). Distinction amongst FOG subtypes enables evaluation of distinctive therapeutic response. Levodopa helps in reducing the frequency and duration of 'off'-related FOG.     

断指冷冻伤后再植的临床经验

目的 探讨断指冷冻伤后再植术前的复温方式及术后注意事项。方法 对在低温环境下丢弃或保存不当而致指体冷冻伤的9例11指，采取自然复温(22～28℃)和温盐水复温(38～42℃)。对冷冻指体复温后，行再植手术。结果 再植术后完全存活6例，部分成活3例。结论 ①温盐水复温方式值得推荐；②指体冷冻伤不应一概列为断指再植禁忌证；③术后积极处理各种并发症是提高断指再植成活率的重要保证。     

Peculiarities of external respiration as a marker of activity of cell respiratory enzymes in rat brain

Rats with catatonic freezing are characterized by low motor and explorative activity in the open field test and specific pattern of external respiration, so-called strenuous respiration, which is accompanied by a higher activity of the respiratory enzymes succinate dehydrogenase and NADH dehydrogenase in the hippocampus and motor cortex. No dependencies on the brain structure and animal age are noted. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 8, pp. 138–140, August, 1997     

Estimated Functional Diameter of Alveolar Septal Microvessels at the Zone I-II Border

Objective : To measure the functional diameter of alveolar septal microvessels under conditions in which the pulmonary arterial pressure and the lung inflation pressure are equal, at 25 cm H₂O (zone I-II border), and to compare these results with those obtained when inflation pressure exceeded arterial pressure by 5 or 10 cm H₂O (zone I). Methods : We perfused isolated rat lungs (P_A 25, P_PA 25, P_LA 0 cm H₂O) with fluorescent latex particles of specific diameters (0.49, 1.05, 2.0, 4.0, or 10 μm) and then prepared samples for histology. Using a confocal, laser-scanning fluorescence microscope, we measured latex particle densities within the septal plane of individual alveoli. We compared these particle densities with those in arterioles supplying the septa and calculated the density ratio. We fit curves produced by the Verniory equation to these ratios to estimate the septal microvessel functional diameter. Results : Particle densities in septa ranged from 0.06 ± 0.02 particles per μm² ‘for 0.49-μm-diameter particles to 0.007 ± 0.004 particles per μm² for 4.0-μm-diameter particles. The 10-μm particles did not enter septa. Calculations based on these data suggest a septal microvessel functional diameter of 6–8 μm. Conclusions : In a previous study, conducted at the same value of P_inflat, but with P_PA set at 15 or 20 (5 or 10 cm H₂O into zone I), we estimated the capillary diameter to be 1.7 μm. Thus, the septal capillary diameter seems to increase by three- to fourfold as P_PA is raised to equal P_inflat.     

Fertilization and early embryology: The effect of equilibration temperature and time on the outcome of ultrarapid freezing of 1-cell mouse embryos

Mouse 1-cell embryos were frozen ultrarapidly at a rate of 2500°C/minin solutions containing 0.25 M sucrose, 0.5% (w/v) bovine serumalbumin (BSA) and 3 or 4.5 M dimethyl sulphoxide (DMSO) or 3or 4.5 M 1, 2-propanediol (PROH) in HEPES-buffered modifiedEarle's medium. We investigated the effect of pre-freeze equilibrationfor 1, 3, 5 or 10 min at 22°C and for 1, 3, 5, 10, 15 or20 min at 4°C. After thawing in a 22°C water bath ata rate of 2500°C/min and dilution in 1 M sucrose in HEPES-bufferedmodified Earle's medium, embryos were cultured in vitro in bicarbonate-bufferedmodified Earle‘s medium with 0.5% (w/v) crystalline BSA.Embryo viability was expressed as the percentage of hatchingor hatched blastocysts resulting from the initial number offrozen-thawed 1-cell embryos. To determine the toxicity of thefreezing solutions, embryo viability was evaluated after equilibrationwithout freezing. Our results demonstrated that the concentration,the equilibration temperature and time are very important factorsin ultrarapid freezing of mouse 1-cell embryos. Optimal viabilitywas found when equilibration was done in 4.5 M DMSO for 3–5min at 22°C and in 4.5 M PROH for 3–5 min at 4°C.The results with regard to exposure to the freezing solutionsindicated that the loss of viability beyond an optimum is notdue solely to cryoprotectant toxicity, in particular not at4°C and not for DMSO. It is suggested that the temperatureand time of equilibration influence the degree of cryoprotectantpermeation and subsequent rehydration, which play a role indetermining freezing susceptibility in terms of ice formation.We conclude that both DMSO and, in contradiction to previousreports, PROH can be used perfectly adequately for ultrarapidfreezing on condition that concentration, and the temperatureand time of equilibration are controlled.     

New Techniques: The use of Fresh-Frozen Tissue in Diagnostic Transmission Electron Microscopy

We have examined the effects of freezing on fresh pathologic human tissue specimens with regard to the fine structural preservation of various organelles that can be of diagnostic importance. Specimens included in this study were frozen either in the cryostat (-20°C) or by quenching in isopentane cooled by liquid nitrogen (-115°C). The results indicate that fresh-frozen tissue that is subsequently fixed and processed for transmission electron microscopy (TEM) provides ultrastructural information that is very nearly equal to that of conventionally processed specimens. Additionally, we performed identical freezing experiments using animal (rat) tissue in order to ensure that the results we obtained using a rather limited number of human specimens were valid. The outcome of these animal experiments thoroughly supports our observations using human pathologic tissue. We believe an appreciation of the fact that fresh-frozen tissue is suitable for TEM examination may become a very valuable resource in the surgical pathology laboratory.     

Potential use of embryo coculture with human in vitro fertilization procedures

Purpose This review was designed to outline potential uses of an embryo co-culture system in human assisted reproduction programs to improve embryo quality and pregnancy rates.Results The various cell types used in embryo co-culture were reviewed in addition to the use of co-culture for both animal and human embryos. Co-culture provides a method to enhance embryo development in an inadequate in vitro environment without compromising embryo quality. Human IVF laboratories have used various types of helper cells to improve rate of development, reduce cell fragmentation rate and in some instances increase pregnancy and implantation rates.Conclusion In conjuction with several assisted reproduction procedures such as IVF, microsurgical fertilization, cryopreservation and genetic evaluation, co-culture may increase the number of viable embryos for replacement and improve pregnancy rates.Presented at the First Asian Symposium on Micromanipulation and Co-culture, April 1, 1993, Singapore.     

甘油蔗糖液对哺乳动物桑椹胚的渗透反应及冻存效果研究

为了提供快速冷冻前胚胎发生部分脱水的科学依据，我们观察了家兔桑椹胚在冷冻保护液中的体积变化。当桑椹胚置于仅含３．０ｍｏｌ／Ｌ或４．０ｍｏｌ／Ｌ甘油液中，桑椹胚立即皱缩，２ｍｉｎ时体积为等渗时体积的５８．９％或５９．６＾％，１０ｍｉｎ时桑椹胚体积达到等渗量的９０．８％或７６．９％，将这些桑椹胚接着移入含３．０ｍｏｌ／Ｌ或４．０ｍｏｌ／Ｌ甘油加０．２５ｍｏｌ／Ｌ蔗糖保护液中，桑椹胚再次发生皱缩主膨大变     

改良液氮冷冻法制备家兔股骨头坏死模型的形态学研究

目的探讨改良液氮冷冻法制备家兔股骨头坏死伴关节面塌陷动物模型的优点,揭示坏死股骨头的修复和塌陷过程。方法对10只成年新西兰大白兔,采用液氮冷冻双侧股骨头负重区,股骨头不造成脱位,分别在术后3、7 d、2、4、6、8周,进行股骨头标本的大体解剖学观察、X线观察和组织切片光镜观察。结果在术后3 d时,股骨头出现坏死,2周后出现修复现象,4周时有3例股骨头关节面出现塌陷,8周时有1例股骨头出现骨性关节炎样变化。结论液氮冷冻股骨头负重区,可制备股骨头坏死伴关节面塌陷的动物模型;但是,其成功率有待提高。