Physiopathology of the cerebellum in the monkey: Part 2. Motor disturbances associated with partial and complete destruction of cerebellar structures

Profound truncal ataxia, dysmetria, postural tremor of the head, trunk and limbs and hypotonia and intention (acting) tremor of the limbs were displayed by 3 monkeys with total cerebellectomy and 2 monkeys with extensive damage to several structures of the cerebellum. Truncal ataxia, dysmetria, hypotonia and intention tremor gradually diminished during the immediate postoperative period whereas postural tremor became less conspicuous. The administration of harmaline, however, exaggerated or evoked postural tremor of the limbs and trunk for a period of 3–4 hr in these monkeys.On the one hand lesions of the vermis of the posterior lobe and of part of the nodulus in one animal or of the interpositus and fastigial nuclei of both sides and the nodulus in another animal or destruction of the uvula and the interpositus nuclei associated with partial involvement of dentate and fastigial nuclei of both sides in a third animal resulted in truncal ataxia and transient dysmetria. The latter animal repeatedly displayed postural tremor of the two upper limbs in response to harmaline. Harmaline, however, did not produce any peculiar effect in the 2 former animals. On the other hand unilateral or bilateral lesions of the dentate and interpositus nuclei or destruction of the left half of the posterior lobe (with or without involvement of the corresponding dentate nucleus) or interruption of the superior cerebellar peduncle did not result in any marked and/or sustained motor impairment. Nine out of 10 monkeys with such lesions, however, displayed postural tremor of the ipsilateral limbs after the administration of harmaline.Truncal ataxia predominantly involves a disturbance of the uvula and nodulus and/or the fastigial nuclei and their interconnections with the vestibular nuclei and, most likely, with the dorsal and medial accessory olives. Dysmetria (or incoordination of the limbs) is apparently related to a combined impairment of structures of the anterior and posterior lobes of the cerebellum and their corresponding interconnections with the cerebellar nuclei. Postural tremor is partly related to a disturbance at the level of a series of phylogenetically more recent structures including parts of the principal olive, neocerebellar cortex and dentate nucleus and the parvocellular division of the red nucleus as well as their nervous interconnections.     

The role of prostaglandin H synthase-mediated metabolism in the induction of oxidative DNA damage by BHA metabolites

The carcinogenicity of the phenolic food antioxidant butylatedhydroxyanisole may be related to its oxidative biotransformationin vivo. In order to determine the ability of BHA, 2-tert-butyl(1,4)hydroquinone(TBHQ) and 2-tert-butyl(1,4)paraquinone (TBQ) to induce oxidativeDNA damage, biological inactivation of single-stranded bacteriophage     

Selective delivery of chemotherapeutic agents with a new catheter system

A new catheter system was used in ten patients (16 infusions) for infusion of chemotherapeutic agents to the sites of malignant gliomas. Thirteen infusions to the supraophthalmic region were successful, as were three infusions to the posterior cerebral region. There were no complications after the infusions. A neurologic complication occurred in one patient in whom two successful supraophthalmic infusions were previously carried out. In this patient the guide wire separated during catheter placement into the posterior cerebral artery.     

Altered functional responsiveness of thymocyte subsets from CD3delta- deficient mice to TCR-CD3 engagement

CD3delta-deficient (delta degrees) mice are defective in alphabeta T cell development. Here we explore the capacity of TCR-CD3 signaling complexes expressed on delta degrees thymocytes to mediate the following functional outcomes in response to antibody cross-linking: (i) the transition from the CD4-CD8- to CD4+CD8+ stage, (ii) the transition from the CD4+CD8+ to CD4+CD8- or CD4-CD8+ stages and (iii) the induction of apoptosis. We provide evidence that CD3deltaepsilon complexes are dispensable for mediating the anti-CD3-mediated CD4-CD8- to CD4+CD8+ transition. On the other hand, CD3delta is critical at the CD4+CD8+ stage. We demonstrate that CD4+CD8+ thymocytes from delta degrees mice, unlike delta degrees CD4-CD8- thymocytes and wild-type CD4+CD8+ thymocytes, require prolonged or consecutive stimuli to elicit functional responses. Depending on the nature of the secondary stimulus, delta degrees thymocytes can be induced to undergo apoptosis or preferential maturation to the CD4-CD8+ stage. Taken together these results indicate that the signaling capacity of the TCR-CD3 complex is noticeably altered in the absence of CD3delta. The essential role of CD3delta at the CD4+CD8+ stage of development correlates with the onset of TCRalpha rearrangement, consistent with a critical structural and/or functional relationship between CD3delta and TCRalpha.      

石杉碱甲类似物的研究Ⅲ．N－甲基吡啶酮石杉碱甲类似物的合成

石杉碱甲（１）是从中草药石杉属植物千层塔（ＬｙｃｏｐｏｄｉｕｍｓｅｒｒａｔｕｍＴｈｕｎｂ．）中分得的一种高效可逆的乙酰胆碱酯酶抑制剂，临床试验证实它对早老性痴呆症有显著疗效。本文报道Ｎ－甲基吡啶酮石杉碱甲类似物２和３的合成。２－甲氧基－５－甲氧羰基－１１－亚甲基－５，９－甲撑环辛－７－烯并吡啶（９）在乙腈中用三甲基氯硅烷和碘化钠选择性脱保护以定量的产率得吡啶酮１０，再用甲醇钠和碘甲烷甲基化得Ｎ－甲基吡啶酮１１，１１经碱性水解，Ｃｕｒｔｉｕｓ重排和氨基的脱保护得Ｎ－甲基吡啶酮石杉碱甲类似物２。通过类似的途径从中间体２－甲氧基－５－甲氧羰基－７－甲基－１１－酮－５，９－甲撑环辛－７－烯并吡啶（１４）合成了类似物３。类似物２和３的乙酰胆碱酯酶抑制活性均低于天然石杉碱甲。     

Mounting and calibration of stairs on piezoelectric force platforms

To calculate the centre of pressure using piezoelectric force plates mounted on pads, no net tensile stresses may be imposed on the surface of the plate. This condition is violated when stairs are attached to the plates, unless the plates are preloaded. Typical shear forces encountered when climbing stairs were used to determine required preloads of approximately 16.4 N/cm step height. Vertical and horizontal loads were applied at known locations on the steps, and points of application were calculated. Deviations were within ± 3 mm. The effect of point of application inaccuracy on calculated joint moments is considerable. A 2 cm medial shift in the point of application resulted in calculated peak knee abduction/adduction moment errors of 35%.