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CeTe3 is a unique platform to investigate the itinerant magnetism in a van der Waals (vdW) coupled metal. Despite chemical pressure being a promising route to boost quantum fluctuation in this system, a systematic study on the chemical pressure effect on Ce3+(4f1) states is absent. Here, we report on the successful growth of a series of Se doped single crystals of CeTe3. We found a fluctuation driven exotic magnetic rotation from the usual easy-axis ordering to an unusual hard-axis ordering. Unlike in localized magnetic systems, near-critical magnetism can increase itinerancy hand-in-hand with enhancing fluctuation of magnetism. Thus, seemingly unstable hard-axis ordering emerges through kinetic energy gain, with the self-consistent observation of enhanced magnetic fluctuation (disorder). As far as we recognize, this order-by-disorder process in fermionic system is observed for the first time within vdW materials. Our finding opens a unique experimental platform for direct visualization of the rich quasiparticle Fermi surface deformation associated with the Fermionic order-by-disorder process. Also, the search for emergent exotic phases by further tuning of quantum fluctuation is suggested as a promising future challenge.

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Experimental autoimmune encephalomyelitis (EAE) is a primary animal model of multiple sclerosis (MS). MS predominantly presents with evidence of lesions in the subcortical periventricular white matter regions of the brain. Research into the pathogenesis of the demyelinating lesions in the brain has been hampered by the fact that conventional models of EAE present with progressive ascending paralysis which recapitulates mainly the spinal cord lesions of multiple sclerosis. There is little evidence of brain involvement. Systemic administration of pertussis toxin (PTx) has been shown to induce the proinflammatory cascade of TGF-beta, IL-6, and Th17 in the central nervous system, which recently has been identified as essential in the development of EAE. To determine whether intracerebroventricular (icv) administration of PTx would result in subcortical periventricular demyelinating lesions in the brain, we examined the effect in a MOG induced EAE model. We found that icv PTx induced subcortical periventricular brain lesions that resemble the pathologic demyelinating lesions of MS. Moreover, icv PTx induced Th17 infiltration and increased expression of cytokines IL-6 and TGF-beta. We thus generated a highly reproducible model with remarkable histological similarities to the predominant demyelinating brain lesions seen in MS.

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BACKGROUND: The role of apolipoprotein E (APOE) polymorphism has been well recognized in other cognitive neurodegenerative disorders, such as Alzheimer disease. Its role in multiple sclerosis (MS) is less clear, though studies indicate that 40% to 60% of patients with MS have evidence of cognitive impairment. OBJECTIVE: To determine whether there is an association between APOE epsilon 4 and cognitive deficits in MS. METHODS: We performed a standardized battery of neuropsychological tests investigating the four cognitive domains commonly impaired in MS and assessed the association of the presence of APOE epsilon 4 with cognition in MS. RESULTS: A strong association was found between the presence of APOE epsilon 4 and cognitive deficits in patients with MS, particularly in the domains of learning and memory. This association was strongest in our youngest cohort (age 31 to 40) of patients with MS. CONCLUSIONS: APOE epsilon 4 is significantly associated with cognitive impairment in patients with multiple sclerosis (MS). However, the modest effects do not justify APOE genotyping of patients with MS in clinical practice.

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The sensitivity of cancers to radiotherapy or chemotherapy may be influenced by susceptibility to apoptosis. We evaluated whether expression of three proteins regulating apoptosis, p53, bcl-2, and bax, could predict the effect of radiotherapy in esophageal cancers. We used immunohistochemical staining for these protein regulators of apoptosis to study biopsy specimens obtained from 25 patients with esophageal squamous cell carcinoma before they underwent preoperative radiotherapy. Effectiveness of radiotherapy was assessed by barium esophagography, esophagoscopy, and computed tomography. Radiotherapy was effective in 12 patients and ineffective in 13 patients. Biopsy specimens from the 25 patients showed expression of p53, bcl-2, and bax to be 48.0%, 32.0%, and 76.0% respectively. Effectiveness of radiotherapy was correlated with p53 expression (p = 0.047), but bcl-2 and bax expression showed no relationship to effectiveness of radiotherapy. Expression of p53 protein in biopsy specimens may predict effectiveness of preoperative radiotherapy in esophageal cancers.

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This study addresses two issues: (1) the comparative neurochemistry of classic tremor type of Parkinson's disease or PD-A and akinetic type of Parkinson's disease or PD-B; and (2) the neurochemistry of levodopa failure syndrome (LDFS). Cerebrospinal fluid from the lateral ventricle was collected from 50 patients with idiopathic Parkinson's disease of PD-A and PD-B. Levels of monoamine neurotransmitters and metabolites were determined using high performance liquid chromatography. We have found that (1) 5-hydroxylindoleacetic acid (5-HIAA) level is significantly lower in PD-B than in PD-A; (2) 5-HIAA level is inversely associated with score of part one of United Parkinson's Disease Rating Score (UPDRS); (3) 5-HIAA level is inversely associated with score of part four of UPDRS; (4) 3-O-methyldopa (3-OMD) level is positively associated with levodopa failure syndrome (LDFS) assessed by part four of UPDRS and inversely associates with 5-HIAA. From these data, it can be inferred that serotonergic activity is decreased in PD-B to a greater extent than in PD-A and that decreased serotonergic activity plays a role in LDFS.

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A huge phyllodes tumor of the breast that appeared grossly malignant in a 43-year-old woman is described. The patient suffered from a large breast tumor thatsuddenly increased in size over 5 months to occupy the entire breast. The tumorwas hard, ulcerated and 20 cm in greatest diameter. Diagnostic imaging(US, CT and MRI)demonstrated a circumscribed mass with a large cystic cavity. She underwent total mastectomy under a diagnosis of malignant breast tumor. Grossly, the cut surface of the tumor showed a large cystic cavity surrounding a fleshy, hemorrhagic and necrotic mass with a lobulared or trabeculared appearance. Unexpectedly, benign phyllodes tumor(PT)without any stromal overgrowth was diagnosed histologically. She has been doing well since total mastectomy. In our case and in many other reported cases, PT does not show any distinctive correlation between pathologic findings and tumor behavior. Thus wide local excision is the preferred initial treatment for PT.

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To investigate the effects of bilateral posteroventral pallidotomy (PVP) for Parkinson's disease (PD), the authors reviewed the technique and neurological outcome in a number of patients who had undergone bilateral pallidotomy. The authors have previously reported the outcome of PVP in 25 bilateral and 25 unilateral surgeries, rating the patient's postural stability, speech, and total Unified Parkinson's Disease Rating Scale scores. A second, separate group of 23 patients who underwent contemporaneous bilateral PVP were evaluated for early onset idiopathic PD, levodopa failure syndrome, and severe bilateral dyskinesia as well as akinetic "off" states. Cognitive and psychological studies were reviewed in 10 patients who demonstrated preoperative impairments in spatial recognition and memory. Following surgery there were significant improvements in these cognitive deficits and no deficits were incurred by surgery. Published reports regarding bilateral operations for PD have emphasized the risks of speech and cognitive deficits. This study shows bilateral PVP to be effective, particularly in patients with bilateral symptoms, including disabling dyskinesia. Additionally, bilateral PVP does not cause additional cognitive or speech deficits. The techniques and indications as well as outcomes and complications are presented and discussed in this report in light of their controversial nature.

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The current interest in stereotactic posteroventral pallidotomy (PVP) for treating Parkinson's disease and the variability of published results have raised questions regarding techniques for target localization. In our technique the probe is guided to the optimum target at the most ventral pallidum and ansa lenticularis by macroelectrode stimulation of the internal capsule and optic tract from within the globus pallidus, with the thresholds providing a relative measure of the electrode proximity to these structures. We have characterized these localizing macroelectrode stimulation parameters in 57 posteroventral pallidotomies with consistent anatomic lesion placement, excellent outcome, and no complications. Using a 1.8 x 2.0 mm radiofrequency electrode for macroelectrode stimulation (RFG-3C, Radionics Inc.), minimum voltages (thresholds) to activate motor (at a frequency of 2 Hz) or visual (at a frequency of 100 Hz) responses as well as impedance measurements were obtained at the final target (Tf) and at distances proximal to Tf along the electrode trajectory. The visual and motor threshold voltages at Tf via our standard approach angles (50 degrees above base plane, 20 degrees from the sagittal plane), had a range of 1.0 to 1.5 V, and 2.0 to 3.5 V respectively. We also found that as the probe approaches Tf there is a significant decrease in voltage thresholds for motor (P < .0001) and visual (P < .0001) responses in an individual patient indicating that the probe is converging on these structures. Increases in impedance between Tf, 2-3 mm, and 4-5 mm proximal to Tf were also statistically significant (P < .0001). Microelectrode recording to electrophysiological neuronal activity at various points along the trajectory towards the target showed distinct firing patterns providing identification of the globus pallidus externus and internus, ansa lenticularis, and optic tract. Macroelectrode electrophysiological stimulation within the target volume, inducing threshold responses in the internal capsule and optic tract, provides for accurate localization of the most effective PVP target in the ansa lenticularis. In unresponsive patients, the utilization of microelectrode recording for the identification of the pallidal borders and the optic tract improves safety.

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Postural instability and gait disorders (PIGD) are the primary causes of disability in many but not all advanced Parkinson's disease (PD) patients. We have measured the concentrations of serotonin, 5-hydroxytryptophan (5-HTP), 5-hydroxy-3-indoleacetic acid (5-HIAA), and homovanillic acid (HVA) in samples of ventricular cerebrospinal fluid from ten PD patients with severe disability from PIGD and from ten PD patients with tremor and levodopa induced dyskinesia as their predominant motor dysfunction. The two groups were prospectively matched for duration of disease and age. No significant differences between the two groups were found in the concentration (mean +/- SD in ng/ml, PIGD dominant vs. tremor-dyskinesia dominant) of 5-HIAA (106 +/- 50 vs. 99 +/- 34) or HVA (1,068 +/- 595 vs. 881 +/- 469). Serotonin concentration was significantly lower (0.7 +/- 0.5 vs. 1.5 +/- 0.9) and 5-HTP concentration was substantially higher (684 +/- 1,054 vs. 6 +/- 5) in the patient group with PIGD as their predominant symptoms. Thus, the distinguishing feature of patients with severe PIGD appears to be a derangement in indoleamine metabolism at the reaction step catalyzed by aromatic amino acid decarboxylase (AADC). These findings suggest that aggravation of PIGD in advanced Parkinson's may be related in part to impaired serotonergic transmission secondary to inhibition or down regulation of AADC.

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An ectomesenchymoma was found in a 62-day-old female calf, and examined immunohistochemically. The neoplastic cells were characterized by positive immunostaining for neurofilaments, glial fibrillary acidic protein, alpha smooth muscle actin, myoglobin, and keratin. This tumour, which displayed neurocytic, astrocytic, and myoblastic differentiation, may have arisen from pluripotential ectomesenchyme. Brain tumours showing multidirectional phenotypic expression presumably occur mainly in fetuses or calves.

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A 17-year-old Russian male with a 9-year diagnosed history of dystonia musculorum deformans manifested as severe tortipelvis, lordosis, and axial and appendicular spastic dystonia, refractory to medical therapy, is reported. This patient underwent a simultaneous bilateral pallidoansotomy with dramatic results. Postoperative evaluation revealed sustained alleviation of all dystonic symptoms and abnormal movements. Rapid recovery of useful strength in all limbs as well as dramatic improvement in coordination occurred. Bilateral posteroventral pallidotomy and pallidoansotomy in the past have proven effective in alleviation of all parkinsonian symptoms, including dyskinesia and dystonia, without the concurrent risk of intransigent side effects associated with bilateral thalamotomy or other stereotactic surgical procedures. Pallidoansotomy may prove to be the treatment of choice for idiopathic torsion dystonia and merits further investigation.

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Chromosome fragmentation, ATP1 disruption, and Southern blot analyses of total DNAs and prime clones of chromosome II showed that three identical ATP1s are present, directing from the telomere to the centromere on the 35-55 kb far from the left telomere sequence of chromosome II. That is, the coding and 5'-, 3'-non-coding regions of ATP1 are repeated 3 times at approximately 7 kb intervals. These three ATP1s are expressed, and one and two ATP1s-disrupted strains, respectively, showed ca.70 and 40% decreases in their ATPase activities and alpha subunit contents, compared to those of the wild type, DC-5 or W303-1A strain, but could grow on glycerol.

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In the past, stereotactic surgical intervention for Parkinson's disease was considered indicated only in those patients with active motor manifestations that were refractory to pharmacological therapy, manifestations such as tremor, rigidity, dystonia, and dyskinesia. With the reintroduction and refinement of Leksell's posteroventral pallidotomy, both akinetic and hyperkinetic symptoms are now amenable to surgical treatment. We have analyzed the results of 126 patients who underwent either unilateral (n = 58) or bilateral (n = 68) posteroventral pallidotomies. The Unified Parkinson's Disease Rating Scale and Hoehn and Yahr Staging Scale were used for preoperative and postoperative objective assessments. Postoperative follow-up evaluation occurred initially at 1 week and subsequently at intervals between 1 and 12 months (mean = 4.5 months) after surgery. Although individual motor subscores on the Unified Parkinson's Disease Rating Scale were significantly reduced (n = 126, P < or = 0.01), the most dramatic findings were the reversal of akinetic symptoms and the elimination of dyskinesia and profound "off" periods. These clinical results, combined with intraoperative microelectrode records revealing pallidal neuronal hyperactivity, suggest a reconsideration of the pathophysiology of akinesia and point to possible mechanisms of akinesia improvement by posteroventral pallidotomy in some parkinsonian subgroups.

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Despite the bilateral appendicular symptoms of Parkinson's disease, bilateral surgical interventions in the basal ganglia have been shunned because of cognitive and speech disturbances following bilateral thalamotomy. However, we present the uncomplicated results of 25 simultaneous posteroventral pallidotomies and compare their obvious superior control of appendicular symptoms as well as axial symptoms with the results of 25 unilateral posteroventral pallidotomies.

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The true accuracy of MRI scanners utilized for target acquisition in functional stereotaxis remains undefined. We have performed pallidotomies at the Loma Linda University Medical Center using both MRI and MRI concomitant with positive contrast ventriculography. A retrospective study of 33 cases revealed significant differences in coordinates obtained by MRI alone and MRI concomitant with ventriculography (antero-posterior coordinates, mean error: 2.6 mm, range 0.5-6.8 mm; Z coordinates: mean error 4.6 mm, range 0-19 mm). While MRI promises excellent target identification, the generated target coordinates significantly stray from the optimal target. Ventriculography corrects the MRI coordinates and demonstrates the position of the radiofrequency probe with respect to the target and anatomic reference points.

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We present the case of a 51-year-old female who had a four-year history of Parkinson's disease with severe "on-off' and disabling progression of symptoms on chronic levodopa therapy. After obtaining FDA approval, we implanted a Medtronic deep brain stimulation lead stereotactically into the right anterior pallidum contralateral to her most symptomatologic side. Intra-operative stimulation trials at 100 Hz caused reproducible reversal of akinetic symptoms and simultaneous microelectrode recording of the posteroventral pallidum revealed decreased neural activity during anterior pallidal stimulation. The patient was evaluated pre-operatively and postoperatively using the Hoehn and Yahr Staging Scale, the Unified Parkinson's Disease Rating Scale (UPDRS), videotape, and a computerized data glove. Six months after implantation, the total UPDRS score was decreased from 68 to 8 and Hoehn and Yahr Staging improved from 3.0 to 1.5 during periods of chronic high frequency stimulation. Dramatic improvements in tremor, dystonia, bradykinesia, and akinesia were noted within seconds of stimulator activation and were also objectively measured using a computerized data glove. This case reveals the potential for therapeutic pallidal stimulation for Parkinson's akinetic symptomatology.

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