1.Wide range of normality in deep tendon reflexes in the normal population
Kheng Seang Lim, Yii Zhan Bong ; Yaw Lim Chaw ; Kean Teng Ho ; Kwang Kwok Lu ; Chin Hwan Lim ; Mei Ling Toh ; Chong Tin Tan
Neurology Asia 2009;14(1):21-25
Background and objective: Deep tendon reflexes are important physical signs in neurological
examination. Despite being an established technique clinically, there is lack of normality data in the
healthy population, especially among the elderly. This study aims to determine the range of normality
in deep tendon reflexes among the adults. Methods: The study subjects consisted of 176 healthy
volunteers. They were examined by trained assessors using standardized protocol. Results: Among the
commonly elicited deep tendon reflexes, isolated absent reflexes were found in up to 34.4% (supinator)
in the older group, and 12.5% (triceps) in the young adults, significantly higher in the older group.
Symmetrical absent reflexes was seen in up to 26.3% of supinator in the older group. Absent reflexes
of the entire limbs both sides were however, much less common particularly among young adults,
with 6.3% of the older group having absent reflexes in the entire lower limbs, and 2.5% in the entire
upper limbs. Isolated asymmetry in reflex was present in up to 17.0% (triceps). However, only 6.3%
had asymmetrical reflexes in the contiguous anatomical region.
Conclusion: Isolated absent or asymmetry deep tendon reflexes were common particularly in the
elderly.
2.Up-regulation of Bax and endonuclease G, and down-modulation of Bcl-X(L) involved in cardiotoxin III-induced apoptosis in K562 cells.
Sheng Huei YANG ; Ching Ming CHIEN ; Mei Chin LU ; Yi Hsiung LIN ; Xiu Wei HU ; Shinne Ren LIN
Experimental & Molecular Medicine 2006;38(4):435-444
Cardiotoxin III (CTX III), a basic polypeptide with 60 amino acid residues isolated from Naja naja atra venom, has been reported to have anticancer activity. CTX III-induced K562 cell apoptosis was confirmed by DNA fragmentation (DNA ladder, sub-G1 formation) and phosphatidylserine (PS) externalization with an IC50 value of 1.7 mug/ml at 48 h. A mechanistic analysis demonstrated that CTX III-induced apoptotic cell death was accompanied by up-regulation of both Bax and endonuclease G (Endo G), and downregulation of Bcl-X(L). CTX III had no effect on the levels of Bcl-2, Bid, XIAP survivin, and AIF proteins. CTX III treatment caused loss of the mitochondrial membrane potential (delta psi m), release of mitochondrial cytochrome c to the cytosol, and activation of both caspase-9 and -3. CTX III-induced apoptosis was significantly blocked by the broad-spectrum caspase inhibitor Z-VAD-FMK. However, CTX III did not generate reactive oxygen species (ROS) and antioxidants, including N-acetylcysteine and catalase, did not block CTX III-induced apoptosis in K562 cells. Modulation of Bax, Bcl-X(L), and the Endo G proteins, release of mitochondrial cytochome c, and activation of caspase-3 and -9 all are involved in the CTX III-triggered apoptotic process in human leukemia K562 cells.
bcl-X Protein/*metabolism
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bcl-2-Associated X Protein/*metabolism
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Up-Regulation/drug effects
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Reactive Oxygen Species/metabolism
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Mitochondrial Proteins/metabolism
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Mitochondrial Membranes/drug effects
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Membrane Potentials/drug effects
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K562 Cells
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Inhibitor of Apoptosis Proteins/metabolism
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Humans
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Endodeoxyribonucleases/*metabolism
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Down-Regulation/drug effects
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Direct Lytic Factors/*pharmacology
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Cytochromes c/metabolism
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Cell Proliferation/drug effects
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Caspases/metabolism
;
Apoptosis/*drug effects