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Acute myeloid leukemia (AML) is a hematological malignant disorder. AML cells are not susceptible to chemotherapeutic drugs because of their multidrug resistance (MDR). Antitubulin agents are currently employed in cancer treatments; however, drug resistance results in treatment failures because of MDR1 expressing cancer cells. We previously synthesized a new tubulin inhibitor, 2-dimethylamino- N-[1-(4-methoxy-benzenesulfonyl)-2,3-dihydro-1H-indol-7-yl]-acetamide (MPT0B169), which inhibits AML cell proliferation by arresting cell cycle at the G2/M phase. In this study, we explored the effect of MPT0B169 on apoptosis in AML HL60 and NB4 cells and MDR1-mediated taxol-resistant HL60/TaxR cells and the underlying mechanism. MPT0B169 induced concentration- and time-dependent apoptosis in these cancer cells, as observed through annexin V/propidium iodide double staining and flow cytometry. Furthermore, DNA fragmentation analysis confirmed MPT0B169-induced apoptosis. MPT0B169 induced a loss of mitochondrial membrane potential, release of cytochrome c into the cytosol, cleavage and activation of caspase-9 and caspase-3, and consequently cleavage of poly (ADP ribose) polymerase. Western blot analysis showed that MPT0B169 markedly reduced Mcl-1 (an antiapoptotic protein) levels; however, it caused no changes in Bcl-2 or BAX (a proapoptotic protein). Knockdown of Mcl-1 using small interfering RNA (siRNA) slightly induced growth inhibition and apoptosis in the HL60 and HL60/TaxR cells. Further investigation revealed that Mcl-1 siRNA enhanced the sensitivity of HL60 and HL60/TaxR cells to MPT0B169-induced growth inhibition and apoptosis. Together, these results demonstrated that MPT0B169-induced apoptosis in nonresistant and MDR1-mediated taxol-resistant AML cells through Mcl-1 downregulation and a mitochondria-mediated pathway. MPT0B169 can overcome MDR1-mediated drug resistance in AML cells. [ABSTRACT FROM AUTHOR]

Background: Traumatic brain injury (TBI), usually due to brain shaking or impact, affects the normal brain function and may lead to severe disability or even death. However, there is paucity of information regarding changes in the physiologic state of humans or animals after brain shaking.Methods: In this study, near-infrared spectroscopy (NIRS) was used to continuously monitor the concentration change of oxy-hemoglobin (HbO2) and deoxy-hemoglobin (HbR) to understand changes in the physiological state during and after brain shaking. Laser Doppler flowmetry was also used to monitor changes in cerebral blood flow under TBI to supplement the investigation. Triphenyltetrazolium chloride (TTC) staining was used to monitor changes of infarction volume corresponding to different impact strengths.Result: The experimental results indicated that concentration changes of HbO2 and total-hemoglobin (HbT) were significantly related to the impact strength. The infarction volume was also significantly related to the impact strength.Conclusion: Therefore, the non-invasive monitoring of concentration changes in HbO 2 , HbR, and HbT using NIRS may have a clinical application for the evaluation of TBI. [ABSTRACT FROM AUTHOR]

Abstract: This study was aimed at examining the effect of tamoxifen, a selective estrogen receptor modulator, on the release of endogenous glutamate in rat cerebral cortex nerve terminals (synaptosomes) and exploring the possible mechanism. Tamoxifen inhibited the release of glutamate that was evoked by the K+ channel blocker 4-aminopyridine (4-AP), and this phenomenon was concentration-dependent and insensitive to the estrogen receptor antagonist. The effect of tamoxifen on the evoked glutamate release was prevented by the chelating extracellular Ca2+ ions, and by the vesicular transporter inhibitor bafilomycin A1. However, the glutamate transporter inhibitor dl-threo-beta-benzyloxyaspartate did not have any effect on the action of tamoxifen. Tamoxifen did not alter the resting synaptosomal membrane potential or 4-AP-mediated depolarization whereas it decreased the 4-AP-induced increase in cytosolic [Ca2+]. Furthermore, the inhibitory effect of tamoxifen on the evoked glutamate release was abolished by the Cav2.2 (N-type) and Cav2.1 (P/Q-type) channel blocker ω-conotoxin MVIIC, but not by the ryanodine receptor blocker dantrolene, or the mitochondrial Na+/Ca2+ exchanger blocker CGP37157. In addition, the protein kinase C (PKC) inhibitors GF109203X or Ro318220 prevented tamoxifen from inhibiting glutamate release. Western blotting showed that tamoxifen significantly decreased the 4-AP-induced phosphorylation of PKC and PKCα. Together, these results suggest that tamoxifen inhibits glutamate release from rat cortical synaptosomes, through the suppression of presynaptic voltage-dependent Ca2+ entry and PKC activity. [Copyright &y& Elsevier]

Rosmarinic acid, a major component of rosemary, is a polyphenolic compound with potential neuroprotective effects. Asreducing the synaptic release of glutamate is crucial to achieving neuroprotectant's pharmacotherapeutic effects, the effect of rosmarinic acid on glutamate release was investigated in rat cerebrocortical nerve terminals (synaptosomes). Rosmarinic acid depressed the 4-aminopyridine (4-AP)-induced glutamate release in a concentration-dependent manner. The removal of extracellular calcium and the blockade of vesicular transporters prevented the inhibition of glutamate release by rosmarinic acid. Rosmarinic acid reduced 4-AP-induced intrasynaptosomal Ca2+ elevation. The inhibition of N-, P/Q-type Ca2+ channels and the calcium/calmodulin-dependent kinase II (CaMKII) prevented rosmarinic acid from having effects on glutamate release. Rosmarinic acid also reduced the 4-AP-induced activation of CaMKII and the subsequent phosphorylation of synapsin I, the main presynaptic target of CaMKII. In addition, immunocytochemistry confirmed the presence of GABAA receptors. GABAA receptor agonist and antagonist blocked the inhibitory effect of rosmarinic acid on 4-AP-evoked glutamate release. Docking data also revealed that rosmarinic acid formed a hydrogen bond with the amino acid residues of GABAA receptor. These results suggested that rosmarinic acid activates GABAA receptors in cerebrocortical synaptosomes to decrease Ca2+ influx and CaMKII/synapsin I pathway to inhibit the evoked glutamate release. [ABSTRACT FROM AUTHOR]

Objective: This study investigates neuropsychological and psychosocial outcomes in patients with traumatic brain injury (TBI) and post-traumatic epilepsy (PTE) compared to a healthy control group., Method: Utilizing a quasi-experimental cross-sectional design, the research involved patients with TBI and PTE referred from a Taiwanese medical center. An age- and education-matched control group of healthy adults without traumatic injuries was also recruited. The study involved analyzing retrospective medical records and applying a comprehensive suite of neuropsychological tests and psychosocial questionnaires., Results: Executive function measures revealed significantly reduced performance in both the TBI and PTE groups compared to controls. Specifically, the MoCA scores were lowest in the PTE group, followed by the TBI group, and highest in the controls. Measures of subjective symptomatology showed comparably elevated levels in both the TBI and PTE groups relative to controls., Conclusion: The research suggests that PTE may intensify the difficulties faced by individuals with TBI, but its impact on overall recovery might not be significant, considering the trajectory of the brain injury itself. Notably, the MoCA results indicate that cognitive deficits are more pronounced in PTE patients compared to those with TBI, underscoring the necessity for targeted neuropsychological assessments. Further investigation is essential to explore PTE's broader neuropsychological and psychosocial impacts. These findings advocate for tailored care strategies that address both neuropsychological and psychosocial needs, ensuring comprehensive management of TBI and PTE.

Disruption of copper homeostasis is closely involved in neurodegenerative disorders. This study examined whether a hybrid copper-binding compound, ( E )-2-(4-(dimethylamino)phenylimino)methyl)quinolin-8-ol (DPMQ), is able to protect NG108-15 cells against oxidative stress. We found that treatment of cells with rotenone or hydrogen peroxide increased cellular oxidative stress and resulted in mitochondrial dysfunction and apoptosis. The cellular levels of Nrf2 and the Cu 2+ chaperone DJ-1 were also decreased. These oxidative detrimental effects were all inhibited when cells were cotreated with DPMQ. DPMQ increased cellular Cu 2+ content, DJ-1 protein level, superoxide dismutase (SOD) activity, and Nrf2 nuclear translocation under basal state. The activity of SOD decreased under redox imbalance and this decrease was blocked by DPMQ treatment, while the protein level of SOD1 remained unaltered regardless of the oxidative stress and DPMQ treatment. Using endogenous proteins, coimmunoprecipitation showed that DJ-1 bound with SOD1 and Nrf2 individually. The amount of Nrf2, bound to DJ-1, consistently reflected its cellular level, while the amount of SOD1, bound to DJ-1, was potentiated by DPMQ, being greater in the basal state than under redox imbalance. Simultaneous inclusion of nonpermeable Cu 2+ chelator tetrathiomolybdate or triethylenetetramine during DPMQ treatment blocked all aforementioned effects of DPMQ, showing that the dependency of the effect of DPMQ on extracellular Cu 2+ . In addition, silencing of DJ-1 blocked the protection of DPMQ against oxidative stress. Taken all together, our results suggest that DPMQ stabilizes DJ-1 in a Cu 2+ -dependent manner, which then brings about SOD1 activation and Nrf2 nuclear translocation; these together alleviate cellular oxidative stress.

Acute myeloid leukemia (AML) is a hematological malignant disorder. AML cells are not susceptible to chemotherapeutic drugs because of their multidrug resistance (MDR). Antitubulin agents are currently employed in cancer treatments; however, drug resistance results in treatment failures because of MDR1 expressing cancer cells. We previously synthesized a new tubulin inhibitor, 2-dimethylamino-N-[1-(4-methoxy-benzenesulfonyl)-2,3-dihydro-1H-indol-7-yl]-acetamide (MPT0B169), which inhibits AML cell proliferation by arresting cell cycle at the G2/M phase. In this study, we explored the effect of MPT0B169 on apoptosis in AML HL60 and NB4 cells and MDR1-mediated taxol-resistant HL60/TaxR cells and the underlying mechanism. MPT0B169 induced concentration- and time-dependent apoptosis in these cancer cells, as observed through annexin V/propidium iodide double staining and flow cytometry. Furthermore, DNA fragmentation analysis confirmed MPT0B169-induced apoptosis. MPT0B169 induced a loss of mitochondrial membrane potential, release of cytochrome c into the cytosol, cleavage and activation of caspase-9 and caspase-3, and consequently cleavage of poly (ADP ribose) polymerase. Western blot analysis showed that MPT0B169 markedly reduced Mcl-1 (an antiapoptotic protein) levels; however, it caused no changes in Bcl-2 or BAX (a proapoptotic protein). Knockdown of Mcl-1 using small interfering RNA (siRNA) slightly induced growth inhibition and apoptosis in the HL60 and HL60/TaxR cells. Further investigation revealed that Mcl-1 siRNA enhanced the sensitivity of HL60 and HL60/TaxR cells to MPT0B169-induced growth inhibition and apoptosis. Together, these results demonstrated that MPT0B169-induced apoptosis in nonresistant and MDR1-mediated taxol-resistant AML cells through Mcl-1 downregulation and a mitochondria-mediated pathway. MPT0B169 can overcome MDR1-mediated drug resistance in AML cells.

Purpose: We want to report an extremely rare condition, brain abscess associated with cerebral amylid angiopathy and hemorrhage., Case Report: We report on a 64-year-old woman who presented initially with moderate fever and headache. She was initially misdiagnosed with a bleeding tumor or arteriovenous malformation rupture and treated without antibiotic therapy. The mass was surgically drained due to neurological deterioration on day 14 after admission. Streptococcus virdians was isolated from the pus culture. The pathology evaluation showed cerebral amyloid angiopathy. She received intravenous antibiotic therapy for 4 weeks. She was eventually discharged home with left quadrantanopia., Conclusion: This case reminds us early recognition of brain abscess formation at the site of intracerebral hemorrhage is very important for prompt and appropriate treatment to improve the overall prognosis.

We report the rare occurrence of herpes zoster reactivation after facial trauma. Herpes zoster appeared in painful groups of distended vesicles containing clear fluid on an erythematous base within the secondary division of the trigeminal nerve. The patient was treated with acyclovir (intravenous, 250 mg, every 8 hours) combined with topical steroids and anti-neuropathic pain medication. The zoster-associated neuralgia subsided gradually 1.5 months after diagnosis. We illustrate this unique case to highlight the fact that reactivation of the varicella zoster virus from childhood chicken pox can reappear at a traumatic site in late adulthood.