Curcumin restores innate immune Alzheimer's disease risk gene expression to ameliorate Alzheimer pathogenesis

Alzheimer's disease (AD) genetics implies a causal role for innate immune genes, TREM2 and CD33, products that oppose each other in the downstream Syk tyrosine kinase pathway, activating microglial phagocytosis of amyloid (Aβ). We report effects of low (Curc-lo) and high (Curc-hi) doses of curcumin on neuroinflammation in APPsw transgenic mice. Results showed that Curc-lo decreased CD33 and increased TREM2 expression (predicted to decrease AD risk) and also increased TyroBP, which controls a neuroinflammatory gene network implicated in AD as well as phagocytosis markers CD68 and Arg1. Curc-lo coordinately restored tightly correlated relationships between these genes' expression levels, and decreased expression of genes characteristic of toxic pro-inflammatory M1 microglia (CD11b, iNOS, COX-2, IL1β). In contrast, very high dose curcumin did not show these effects, failed to clear amyloid plaques, and dysregulated gene expression relationships. Curc-lo stimulated microglial migration to and phagocytosis of amyloid plaques both in vivo and in ex vivo assays of sections of human AD brain and of mouse brain. Curcumin also reduced levels of miR-155, a micro-RNA reported to drive a neurodegenerative microglial phenotype. In conditions without amyloid (human microglial cells in vitro, aged wild-type mice), Curc-lo similarly decreased CD33 and increased TREM2. Like curcumin, anti-Aβ antibody (also reported to engage the Syk pathway, increase CD68, and decrease amyloid burden in human and mouse brain) increased TREM2 in APPsw mice and decreased amyloid in human AD sections ex vivo. We conclude that curcumin is an immunomodulatory treatment capable of emulating anti-Aβ vaccine in stimulating phagocytic clearance of amyloid by reducing CD33 and increasing TREM2 and TyroBP, while restoring neuroinflammatory networks implicated in neurodegenerative diseases.

Arthroscopic decompression with indigo carmine for treating paralabral cysts in the shoulder

Paralabral cysts in the shoulder are a relatively rare pathology. It is sometimes difficult to detect the location of a paralabral cyst in the shoulder using arthroscopy, and it can be difficult to confirm sufficient decompression by arthroscopy. We describe the case of a 64-year-old woman who underwent arthroscopic decompression for a paralabral cyst in the shoulder. Indigo carmine was injected into the cyst under ultrasonography guidance just before the operation. The leakage point of indigo carmine was detected using arthroscopy. Arthroscopic decompression was performed until the indigo carmine was completely discharged. Her shoulder pain, limited range of motion, and muscle weakness during abduction and external rotation improved postoperatively. Magnetic resonance imaging confirmed the disappearance of the cyst. Arthroscopic decompression using an ultrasonography-guided injection of indigo carmine is a useful treatment for a paralabral cyst in the shoulder.

Clinical application of radial magnetic resonance imaging for evaluation of rotator cuff tear

BACKGROUND

Magnetic resonance imaging is useful for evaluating the rotator cuff, but some tendinous insertions cannot be assessed using oblique sagittal, oblique coronal, and axial magnetic resonance (MR) images because of the presence of the partial volume effect.

HYPOTHESIS

The purpose of this study was to determine whether radial-slice MR images could reveal normal rotator cuff insertions and rotator cuff tears more clearly than conventional MR images.

PATIENTS AND METHODS

The study included 18 subjects with normal rotator cuffs and 30 with rotator cuff tears. MR images of rotator cuff insertions sliced into radial, oblique coronal, and axial sections were obtained. The extent to which normal rotator cuff insertions and rotator cuff tears were visualized in each of the three MR images was evaluated.

RESULTS

The top to posterior portions of the rotator cuff insertions from 0° to 120° could be visualized in the radial MR images. In comparison, the posterior portions of the rotator cuff insertions could not be visualized around 45° in both the oblique coronal and axial MR images.

DISCUSSION

These findings demonstrate that radial MR images are superior to the oblique coronal and axial MR images regarding their ability to accurately visualize rotator cuff insertions. Radial MR images also revealed greater detail around 45° in the posterior area of the rotator cuff tears than the oblique coronal and axial MR images. Radial MR images are particularly useful for visualizing clinically important posterosuperior rotator cuff tears.

LEVEL OF EVIDENCE

Level III - Diagnostic study.

Fluvoxamine alleviates ER stress via induction of Sigma-1 receptor

We recently demonstrated that endoplasmic reticulum (ER) stress induces sigma-1 receptor (Sig-1R) expression through the PERK pathway, which is one of the cell's responses to ER stress. In addition, it has been demonstrated that induction of Sig-1R can repress cell death signaling. Fluvoxamine (Flv) is a selective serotonin reuptake inhibitor (SSRI) with a high affinity for Sig-1R. In the present study, we show that treatment of neuroblastoma cells with Flv induces Sig-1R expression by increasing ATF4 translation directly, through its own activation, without involvement of the PERK pathway. The Flv-mediated induction of Sig-1R prevents neuronal cell death resulting from ER stress. Moreover, Flv-induced ER stress resistance reduces the infarct area in mice after focal cerebral ischemia. Thus, Flv, which is used frequently in clinical practice, can alleviate ER stress. This suggests that Flv could be a feasible therapy for cerebral diseases caused by ER stress.

Proximal femoral nail for treatment of trochanteric femoral fractures

PURPOSE

To report outcomes of 87 consecutive patients treated with a proximal femoral nail (PFN) for trochanteric femoral fractures.

METHODS

17 men and 70 women aged 58 to 95 (mean, 85) years with trochanteric femoral fractures underwent PFN fixation using an intramedullary nail, a lag screw, and a hip pin. Fractures were classified according to the AO system; the most common fracture type was A2 (n=45), followed by A1 (n=36) and A3 (n=6). The position of the lag screw within the femoral head was measured. The lateral slide of the lag screw after fracture consolidation was measured by comparing the immediate postoperative and final anteroposterior radiographs.

RESULTS

90% of lag screws were placed in an optimal position. The length of lateral slide of the lag screw in stable A1 fractures was significantly less than that in unstable A2 fractures; it was over 10 mm in 7 of 45 patients with A2 fractures. Cut-out of lag screw did not occur, suggesting that free sliding of the lag screw facilitates direct impaction between fragments.

CONCLUSION

A PFN is useful for the treatment of trochanteric femoral fractures.

A molecular chaperone inducer protects neurons from ER stress

The endoplasmic reticulum (ER) stress response is a defense system for dealing with the accumulation of unfolded proteins in the ER lumen. Recent reports have shown that ER stress is involved in the pathology of some neurodegenerative diseases and cerebral ischemia. In a screen for compounds that induce the ER-mediated chaperone BiP (immunoglobulin heavy-chain binding protein)/GRP78 (78 kDa glucose-regulated protein), we identified BiP inducer X (BIX). BIX preferentially induced BiP with slight inductions of GRP94 (94 kDa glucose-regulated protein), calreticulin, and C/EBP homologous protein. The induction of BiP mRNA by BIX was mediated by activation of ER stress response elements upstream of the BiP gene, through the ATF6 (activating transcription factor 6) pathway. Pretreatment of neuroblastoma cells with BIX reduced cell death induced by ER stress. Intracerebroventricular pretreatment with BIX reduced the area of infarction due to focal cerebral ischemia in mice. In the penumbra of BIX-treated mice, ER stress-induced apoptosis was suppressed, leading to a reduction in the number of apoptotic cells. Considering these results together, it appears that BIX induces BiP to prevent neuronal death by ER stress, suggesting that it may be a potential therapeutic agent for cerebral diseases caused by ER stress.

Selective inhibition of Abeta42 production by NSAID R-enantiomers

Non-steroidal anti-inflammatory drugs (NSAIDs) have been associated with reduced risk for Alzheimer's disease (AD) and selected NSAIDs racemates suppress beta-amyloid (Abeta) accumulation in vivo and Abeta42 production in vitro. Clinical use of NSAIDs for preventing or treating AD has been hampered by dose-limiting toxicity believed to be due to cyclooxygenase (COX)-inhibition that is reportedly not essential for selective Abeta42 reduction. Profens have racemates and R-enantiomers were supposed to be inactive forms. Here we demonstrate that R-ibuprofen and R-flurbiprofen, with poor COX-inhibiting activity, reduce Abeta42 production by human cells. Although these R-enantiomers inhibit nuclear factor-kappaB (NF-kappaB) activation and NF-kappaB can selectively regulate Abeta42, Abeta42 reduction is not mediated by inhibition of NF-kappaB activation. Because of its efficacy at lowering Abeta42 production and low toxicity profile, R-flurbiprofen is a strong candidate for clinical development.

Increased production of beta-amyloid and vulnerability to endoplasmic reticulum stress by an aberrant spliced form of presenilin 2

An alternative spliced form of the presinilin 2 (PS2) gene (PS2V) lacking exon 5 has previously been reported to be expressed in human brains in sporadic Alzheimer's disease (AD). PS2V encodes the amino-terminal portion of PS2, which contains residues Met1-Leu119 and 5 additional amino acid residues (SSMAG) at its carboxyl terminus. Here we report that PS2V protein impaired the signaling pathway of the unfolded protein response, similarly to familial AD-linked PS1 mutants and caused significant increases in the production of both amyloid beta40 and beta42. Interestingly, PS2V-encoding protein was expressed in neuropathologically affected neurons of the hippocampal CA1 region and temporal cortex in AD patients. These findings suggest that the aberrant splicing of the PS2 gene may be implicated in the neuropathology of sporadic AD.

Absence of endoproteolysis but no effects on amyloid beta production by alternative splicing forms of presenilin-1, which lack exon 8 and replace D257A

It is well known that presenilin-1 (PS1) is involved in cleavage of amyloid precursor protein (APP) at the gamma-secretase site, and that the amino acids residues of D257 and D385 in PS1 are critical for this cleavage of APP and the endoproteolysis of itself. An alternatively spliced form of PS1 skipping exon 8 (PS1d8), which has D257A at the splice junction of exon 7/9, is expressed in human brain and in some cell lines. In this study, we examined production of Amyloid beta (A beta) and the endoproteolysis of the holoproteins in PS1d8-expressing neuroblastoma cells. Western blotting showed an absence of endoproteolysis in PS1d8. However, PS1d8 did not affect the production of A beta, which is different from the artificial point mutant PS1D257A. These results suggest that endoproteolysis of PS1 and gamma-secretase activity could be independent.

Regulatory mechanisms of TRAF2-mediated signal transduction by Bcl10, a MALT lymphoma-associated protein

To elucidate the function of Bcl10, recently cloned as an apoptosis-associated gene mutated in MALT lymphoma, we identified its binding partner TRAF2, which mediates signaling via tumor necrosis factor receptors. In mammalian cells, low levels of Bcl10 expression promoted the binding of TRAF2 and c-IAPs. Conversely, excessive expression inhibited complex formation. Overexpressed Bcl10 reduced c-Jun N-terminal kinase activation and induced nuclear factor kappaB activation downstream of TRAF2. To determine whether overexpression of Bcl10 could perturb the regulation of apoptosis in vivo, we generated Bcl10 transgenic mice. In these transgenic mice, atrophy of the thymus and spleen was observed at postnatal stages. The morphological changes in these tissues were caused by acceleration of apoptosis in T cells and B cells. The phenotype of Bcl10 transgenic mice was similar to that of TRAF2-deficient mice reported previously, indicating that excessive expression of Bcl10 might deplete the TRAF2 function. In contrast, in the other organs such as the brain, where Bcl10 was expressed at high levels, no apoptosis was detected. The altered sensitivities to overexpressed Bcl10 may have been due to differences in signal responses to Bcl10 among cell types. Thus, Bcl10 was suggested to play crucial roles in the modulation of apoptosis associated with TRAF2.

Tau protein is a potential biological marker for normal pressure hydrocephalus

A biological marker for normal pressure hydrocephalus (NPH) is beneficial for evaluation of its severity and of indications for shunt operation. Tau protein was initially considered as a biological marker in cerebrospinal fluid (CSF) from Alzheimer's patients. Recently, it has been demonstrated that degeneration in the brain causes elevation of tau in CSF. Therefore, the tau level in CSF from NPH patients was evaluated. Tau levels in CSF from NPH patients were significantly higher than that in controls. The tau levels were correlated with the severity of dementia, urinary incontinence, and gait disturbance in NPH. These results suggest that CSF tau may be useful as a biological marker for NPH to determine the level of neuronal degeneration.

Presenilin-1 mutations downregulate the signalling pathway of the unfolded-protein response

Missense mutations in the human presenilin-1 (PS1) gene, which is found on chromosome 14, cause early-onset familial Alzheimer's disease (FAD). FAD-linked PS1 variants alter proteolytic processing of the amyloid precursor protein and cause an increase in vulnerability to apoptosis induced by various cell stresses. However, the mechanisms responsible for these phenomena are not clear. Here we report that mutations in PS1 affect the unfolded-protein response (UPR), which responds to the increased amount of unfolded proteins that accumulate in the endoplasmic reticulum (ER) under conditions that cause ER stress. PS1 mutations also lead to decreased expression of GRP78/Bip, a molecular chaperone, present in the ER, that can enable protein folding. Interestingly, GRP78 levels are reduced in the brains of Alzheimer's disease patients. The downregulation of UPR signalling by PS1 mutations is caused by disturbed function of IRE1, which is the proximal sensor of conditions in the ER lumen. Overexpression of GRP78 in neuroblastoma cells bearing PS1 mutants almost completely restores resistance to ER stress to the level of cells expressing wild-type PS1. These results show that mutations in PS1 may increase vulnerability to ER stress by altering the UPR signalling pathway.

Distribution of synaptosomal-associated protein 25 in nerve growth cones and reduction of neurite outgrowth by botulinum neurotoxin A without altering growth cone morphology in dorsal root ganglion neurons and PC-12 cells

Synaptosomal-associated protein 25 has been regarded as one of the target-associated soluble N-ethylmaleimide-sensitive fusion attachment protein receptors essential for exocytosis of vesicles in synapses. We have previously reported that cleavage of syntaxin, which is another target-associated soluble N-ethylmaleimide-sensitive fusion attachment protein receptor, with botulinum neurotoxin C1 resulted in inhibition of neurite extension and morphological changes including growth cone collapse and large vacuole formation. As an attempt to explore the mechanism of growth cone extension, we examined the ultrastructural localization of synaptosomal-associated protein 25 in growth cones with or without treatment of botulinum neurotoxin A, which cleaves synaptosomal-associated protein 25. In dorsal root ganglion neurons, light microscopy demonstrated synaptosomal-associated protein 25 immunoreactivity throughout the neurons, including the cell bodies, neurites and growth cones. Using electron microscopy, gold signals immunoreactive for synaptosomal-associated protein 25 were identified diffusely in the cytoplasm of the growth cones. In contrast, in PC-12 cells, a large number of gold signals were localized on the plasma membranes. High levels of signal were also found in the cytoplasm in the central region of the growth cones. We also confirmed that botulinum neurotoxin A treatment reduced neurite extension by about 50%. However, both in dorsal root ganglion neurons and in PC-12 cells we found no differences in the ultrastructure nor in the localization of synaptosomal-associated protein 25 between growth cones with and without toxin treatment. These results indicate that cleavage of synaptosomal-associated protein 25 inhibits growth cone extension in a manner different than that of syntaxin cleavage. The results of this study suggest the possibility that synaptosomal-associated protein 25 is involved in growth cone extension through a process independent of vesicle fusion.

IPP isomerase, an enzyme of mevalonate pathway, is preferentially expressed in postnatal cortical neurons and induced after nerve transection

To understand the molecular mechanisms underlying the developmental processes of the cerebral cortex, we screened genes whose mRNA expression was up-regulated in neonatal in the rat cortex to a greater extent than in adult by differential display and obtained five genes. Among these genes, we focused on pyrophosphate (isopentenyl diphosphate, dimethylallyl diphosphate: IPP) isomerase gene, the product of which is known as an enzyme of the mevalonate pathway. Rat IPP isomerase was recently cloned and the gene expression was shown to be dependent on the activation of the mevalonate pathway. Its expression and roles in the brain, however, have not been investigated hitherto. In the present study, Northern blots and in situ hybridization analysis showed that at embryonic stage weak signals for IPP mRNA were diffusely detected in the CNS, and the signal in the cortex became intense at postnatal day 1 and maximized in almost all neurons of all layers at postnatal day 7 with a subsequent reduction. At 8 weeks, the expression of IPP isomerase mRNA in neurons decreased, while it was detected in the oligodendrocytes in the regions containing abundant nerve fibers. These findings suggested that IPP isomerase contributes to postnatal neuronal maturation and myelination. We also demonstrated that IPP isomerase mRNA is induced after nerve axotomy, which suggests a relationship between neuronal regeneration and IPP isomerase. Taken together, these results suggest that elevation of IPP isomerase mRNA levels in neurons contributes to construction of nerve fibers both during the postnatal period in the cortex and their regeneration.

Handling characteristics of braided suture materials for tight tying

To establish criteria for characterizing synthetic sutures, the handling characteristics of silk suture were analyzed. The characteristics that distinguish silk suture from other braided suture materials are its good "knot security" and relatively low "tiedown resistance." Analytic consideration of knot security suggests that not only superficial friction but also resistance force produced by cross-sectional deformity of braided threads plays an important role in silk's superior performance. Results of a "pullout friction test," developed to quantitatively evaluate resistance produced by surface friction and cross-sectional deformity suggest that the superiority of silk thread can be explained in terms of high static withdrawal resistance under low loads and relatively low dynamic withdrawal resistance under high loads.

The cell death-promoting gene DP5, which interacts with the BCL2 family, is induced during neuronal apoptosis following exposure to amyloid beta protein

DP5, which contains a BH3 domain, was cloned as a neuronal apoptosis-inducing gene. To confirm that DP5 interacts with members of the Bcl-2 family, 293T cells were transiently co-transfected with DP5 and Bcl-xl cDNA constructs, and immunoprecipitation was carried out. The 30-kDa Bcl-xl was co-immunoprecipitated with Myc-tagged DP5, suggesting that DP5 physically interacts with Bcl-xl in mammalian cells. Previously, we reported that DP5 is induced during neuronal apoptosis in cultured sympathetic neurons. Here, we analyzed DP5 gene expression and the specific interaction of DP5 with Bcl-xl during neuronal death induced by amyloid-beta protein (A beta). DP5 mRNA was induced 6 h after treatment with A beta in cultured rat cortical neurons. The protein encoded by DP5 mRNA showed a specific interaction with Bcl-xl. Induction of DP5 gene expression was blocked by nifedipine, an inhibitor of L-type voltage-dependent calcium channels, and dantrolene, an inhibitor of calcium release from the endoplasmic reticulum. These results suggested that the induction of DP5 mRNA occurs downstream of the increase in cytosolic calcium concentration caused by A beta. Moreover, DP5 specifically interacts with Bcl-xl during neuronal apoptosis following exposure to A beta, and its binding could impair the survival-promoting activities of Bcl-xl. Thus, the induction of DP5 mRNA and the interaction of DP5 and Bcl-xl could play significant roles in neuronal degeneration following exposure to A beta.

Localization of tyrosine-phosphorylated proteins in cultured mouse dorsal root ganglion neurons

The present study, using confocal laser scanning microscopy and immunoelectron microscopy, examined the intracellular localization of tyrosine-phosphorylated proteins in cultured mouse dorsal root ganglion neurons with special reference to their growth cones. The growth cone is the specialized structure formed at the growing tip of the axon; characteristically highly motile with filopodia on the surface, it is responsible for the extension and guidance of the neurites to the appropriate targets during nerve regeneration. It has been suggested that protein-tyrosine phosphorylation plays an important role in the intracellular signal transduction that regulates the extension and motility of growth cones. By fluorescence immunocytochemistry, phosphotyrosine immunoreactivity was found in the growth cones and neurites. Some of the filopodia exhibited strong immunoreactivity at their tips. By immunoelectron microscopy, a large number of immunogold particles (gold particles conjugated to the secondary antibody) were seen to be distributed in the cytoplasm and some were observed on the plasma membrane in the growth cones, whereas in the neurites the density of immunogold particles was the same in the axoplasm as on the plasma membranes. These findings suggest that in the growth cones phosphotyrosines might mainly be involved in intracellular signaling for maintaining their high motility whereas in the neurites they might mostly be associated with the receptor proteins at the plasma membrane for adhesion as well as for growth of neurites. Thus, tyrosine phosphorylation might contribute to different functions for growth cones and neurites.

Long acellular nerve transplants for allogeneic grafting and the effects of basic fibroblast growth factor on the growth of regenerating axons in dogs: a preliminary report

Sciatic nerves were excised from 3 beagle dogs about 5 h after their sacrifice, treated three times by freezing and thawing, and stored in physiological saline for 3 months at -20 degrees C until used. Nerve segments 5 cm in length prepared from these stored nerves were transplanted to the common peroneal nerve in the right hindlimb of beagle dogs. Sixteen beagle dogs in total were used, in four treatment groups of two pairs each studied at 1 and 3 months. Five-hundred microliters basic fibroblast growth factor (bFGF) of two different concentrations (10 micrograms/300 microliters and 100 micrograms/300 microliters) which were impregnated in 0.5 ml gelatin hydrogels was applied around the sutured allografts. Autografting was also done in 4 beagle dogs, with no bFGF application. One month after the grafting, no regenerating nerves extended beyond the middle of the transplant in any of the allografts, except in the autografts in which a number of regenerated (myelinated) axons were present. Three months after the grafting, an abundance of myelinated axons was found at the middle of the graft: the numbers of axons per 10(4) micron 2 were 22.6 in the autografts and 10.6, 10.4 and 19.2 in the allografts treated with no bFGF, low-dose bFGF, and high-dose bFGF, respectively. Regenerating axons extended into the host nerve: the numbers of myelinated axons at the level 1.5 cm distal to the distal suture were 35.7, 0.9, 3.8, and 12.1 per 10(4) micron 2 in the above respective order. Although it was inferior in quality to the autograft, peripheral nerve regeneration was extensive in the distal nerve using freeze-thawed and bFGF-treated allografts at 3 months. Electromyography showed that the peroneus longus muscle responded to the electrical stimuli given at the site proximal to the transplant in all four groups. These data indicate that a 5-cm acellular nerve segment containing Schwann cell basal laminae can be used successfully as an allograft without any immunosuppressants and that exogenously applied bFGF can improve nerve regeneration by enhancing the growth of regenerating axons.

Increased tau protein level in postmortem cerebrospinal fluid

Microtubule-associated protein tau has been reported to be significantly increased in cerebrospinal fluid (CSF) of the patients with Alzheimer's disease (AD), which suggests that it is possibly a biological marker for the diagnosis of AD. The underlying mechanism of the increased tau level in CSF, however, is not known. In this study, the tau levels were compared between antemortem and postmortem CSF. The postmortem tau levels in CSF were significantly increased in all groups including AD, neurological control, and nondemented control. A striking elevation of CSF tau was observed during the postmortem change with the nondemented subjects. These findings may offer some insight into the understanding of the mechanism of the increased tau level in CSF with AD and other related disorders.

Temporal and regional profiles of cytoskeletal protein accumulation in the rat brain following traumatic brain injury

To characterize the cytoskeletal aberration due to traumatic injury, temporal and regional profiles of changes in immunoreactivity of microtubule-associated protein 2 (MAP2), neurofilament heavy subunit protein (NFH) and heat shock protein 72 (HSP72) were investigated after different magnitudes of traumatic brain injury by fluid percussion. The experimental rat brain was perfusion-fixed at 1, 6 and 24 hours after traumatic brain injury. Conventional histological staining has demonstrated that the mildest traumatic brain injury (1.0 atm) induced no neuronal loss at the impact site and that neuron loss was apparent when traumatic brain injury was increased to 4.3 atm. The mildest traumatic brain injury, however, caused a significant increase in HSP72 immunoreactivity in the superficial cortical layers at the impact site as early as 1 hour after the injury. In the case of severe traumatic brain injury (4.3 atm), neuron loss was apparent in the area at the impact site, but the increase in HSP72 immunoreactivity was moderate, and it was observed only after 6 hours in the deep cortical layers under the necrotic area. The increased immunostaining of MAP2 was demonstrated in damaged axons and neuronal perikarya in the wider area surrounding the impact site at 6 and 24 hours after the injury. Six and 24 hours after the injury, perikaryal accumulation of neurofilament was observed, and the accumulated neurofilament was mostly phosphorylated. These results indicate that the severe traumatic brain injury of 4.3 atm triggers the abnormal accumulation of cytoskeletal proteins in neuronal perikarya, most probably due to an impairment of axonal transport. It is implied that the increased expression of HSP72 may be involved in the protective process of neurons after traumatic brain injury.

Classification system of complications in neuroleptic malignant syndrome

Our group treated 13 cases of neuroleptic malignant syndrome (NMS) over a period of 8 years. Based on the clinical severity of complications, the cases were classified into three types: mild, with no complications; moderate, with only respiratory disturbance; and severe, with respiratory disturbance and renal failure. The major complications affecting the prognosis of NMS are respiratory disturbance and renal failure. Renal failure is also associated with the occurrence of disseminated intravascular coagulation and rhabdomyolysis. The proposed classification system for NMS patients is useful in selecting the appropriate therapeutic strategy for this disorder. The clinical data were analyzed to determine the factors in the process of deterioration in NMS.

The effects of repetitive mild brain injury on cytoskeletal protein and behavior

The purpose of this study was to examine the hypothesis if repetition of mild mechanical brain injury induces the pathological process related to Alzheimer's disease. After defining the magnitude of the subthreshold brain injury which does not induce brain tissue damage by a single hit, the subthreshold mild impact (1.0 atm) was repeated 7 times every 24 h. One week after the last impact, abnormal accumulation of microtubule-associated protein 2 (MAP2) and phosphorylated neurofilament 200 kD (p-NFH) was observed in neuronal perikarya and dendrites. One month after percussion, the number of MAP2-and p-NFH-positive neuronal perikarya was increased and observed in remote areas including the contralateral cortex and the hippocampus. Tau-1 immunoreactivity was increased in deep cortical neurons of the ipsilateral side after dephosphorylation, indicating the accumulation of phosphorylated tau in neuronal perikarya. The abnormal accumulation of cytoskeletal proteins in neuronal perikarya may be due to impaired axonal transport caused by mechanical brain injury. The behavioral study revealed that after repetitive mild percussion, rats show less efficient habituation to a new environment. It is suggested that the repetition of subthreshold mechanical brain injury may trigger cytoskeletal alteration related to neuronal degeneration.