Carpets with visual cues can improve gait in Parkinson's disease patients: may be independent of executive function

BACKGROUND

Gait impairment is common in Parkinson's disease (PD) patients, which greatly reduces their quality of life. Executive dysfunction is associated with gait impairment. Compensatory strategies, including visual cues, have been shown to be effective in improving PD gait. In this study, we aimed to understand whether carpets with visual cues could improve PD gait, and how the improvement varies across patients with different executive function state.

METHODS

We designed carpets with chessboard and stripe cues. A total of 65 Chinese PD patients were recruited. Movement Disorder Society Unified Parkinson's Disease Rating Scale, L-dopa equivalent daily dosage, Hoehn & Yahr stage, Frontal Assessment Battery, Mini Mental State Examination Scale, Hamilton Anxiety Scale, and Hamilton Depression Scale were evaluated. Gait parameters including stride length, gait speed and fall risk were recorded by a wearable electronic device.

RESULTS

The stride length and gait speed were significantly improved and the fall risk was significantly mitigated when PD patients walked on carpets with chessboard and stripe patterns. Further analysis showed the amelioration of gait parameters was independent of executive dysfunction.

CONCLUSIONS

Our study demonstrates that carpets with visual cues can improve the gait of PD patients even in those with mild executive dysfunction.

Isolated unilateral oculomotor palsy caused by pure midbrain infarction: a case report

Purpose: Multiple etiologies may cause oculomotor nerve palsies. Identification of different etiologies is very important for subsequent treatment. Midbrain infarction is a rare cause of oculomotor nerve palsy. Materials and methods: We herein present a case of isolated unilateral oculomotor paresis caused by pure midbrain infarction. Results: Her pupillary sphincter and inferior rectus muscles were selectively spared. The symptoms were completely relieved after two months of antiplatelet therapy. We proposed that fibers from Edinger-Westphal nucleus and inferior rectus nucleus do not course through the paramedian area of the midbrain. Conclusions: Our report adds to the understanding of fascicles arrangement in the midbrain.

Neck pain and absence of cranial nerve symptom are clues of cervical myelopathy mimicking stroke: Two case reports

BACKGROUND

Cervical myelopathy is a potential stroke imitator, for which intravenous thrombolysis would be catastrophic.

CASE SUMMARY

We herein present two cases of cervical myelopathy. The first patient presented with acute onset of right hemiparesis and urinary incontinence, and the second patient presented with sudden-onset right leg monoplegia. The initial diagnoses for both of them were ischemic stroke. However, both of them lacked cranial nerve symptom and suffered neck pain at the beginning of onset. Their cervical spinal cord lesions were finally confirmed by cervical computed tomography. A literature review showed that neck pain and absence of cranial nerve symptom are clues of cervical myelopathy.

CONCLUSION

The current report and the review remind us to pay more attention to these two clues in suspected stroke patients, especially those within the thrombolytic time window.

Case report: Blepharospasm in peak-dose dyskinesia may benefit from amantadine in Parkinson's disease

Introduction

Blepharospasm is uncommon in Parkinson's disease, especially in the peak-dose dyskinesia period.

Case presentation

We herein present the case of a patient with PD who developed blepharospasm in the peak-dose dyskinesia period. The symptom was improved by taking amantadine.

Conclusion

The current report expands the phenomenology of peak-dose dykinesia in PD to include dystonic blepharospasm. This complication of levodopa therapy may respond to amantadine despite the dystonic appearance of movements.

Parkinsonism-Hyperpyrexia Syndrome and Dyskinesia-Hyperpyrexia Syndrome in Parkinson's Disease: Two Cases and Literature Review

Parkinsonism-hyperpyrexia syndrome (PHS) and dyskinesia-hyperpyrexia syndrome (DHS) are rare but exhibit life-threatening complications in Parkinson’s disease (PD). We herein presented two cases of PD patients and performed a comprehensive and comparative literature review for these two syndromes. The first case was diagnosed as PHS with cerebral salt wasting syndrome caused by abrupt withdrawal of antiparkinsonian medication. Her symptoms were gradually remitted with reinstitution of the medication. The second one was an early-stage PD patient diagnosed as DHS in association with abuse of antiparkinsonian drugs. Her symptoms were gradually remitted with reduced dosage of dopaminergic drugs. Results of literature reviews revealed a total of 56 and 13 cases of PHS and DHS, respectively, and they were more likely to occur in elderly and long-term PD patients. These two syndromes showed different female-to-male ratio, similar mortality, and different recovery time. There were stark differences between PHS and DHS, including triggers (abrupt drug stoppage versus drug abuse), symptoms (worsened tremor and rigidity versus continuous dyskinesia), and treatment (drug reinstitution versus drug reduction). In summary, our reports and the review provide new insights into PHS and DHS in association with PD and may facilitate rapid discrimination of the syndromes for timely and proper treatment to reduce mortality.

Diterpenoids from Euphorbia helioscopia and their enhancement of NK cell-mediated killing of NSCLC cells

Fourteen previously undescribed diterpenoids, including an unusual diterpenoid (1) with a 9,10-seco-jatrophane skeleton, ten jatrophane-type diterpenoids (2-11), two lathyrane-type diterpenoids (12, 13), and an abietane-type diterpenoid (14), together with thirty-six known ones (15-50), were isolated from the whole plants of Euphorbia helioscopia L. The structures of the new isolates were characterized by spectroscopic methods, single-crystal X-ray diffraction analysis, and computational prediction of ECD and chemical shifts. Thirty-nine abundant diterpenoids were evaluated for their enhancement of NK cell-mediated killing of NSCLC cells. As a result, compounds 24, 33, and 41 were found to significantly enhance the killing activity of NK cells towards H1299-luci cells and A549-luci cells at the concentration of 2.5 μM.

Cystathionine β-synthase mediated PRRX2/IL-6/STAT3 inactivation suppresses Tregs infiltration and induces apoptosis to inhibit HCC carcinogenesis

Background

Hepatocellular carcinoma (HCC) is characterized by inflammation and immunopathogenesis. Accumulating evidence has shown that the cystathionine β-synthase/hydrogen sulfide (CBS/H₂S) axis is involved in the regulation of inflammation. However, roles of CBS in HCC development and immune evasion have not been systematically investigated, and their underlying mechanisms remain elusive. Here, we investigated the roles of CBS in tumor cells and tumor microenvironment of HCC.

Methods

236 HCC samples were collected to detect the expression of CBS, cleaved Caspase-3 and paired related homeobox 2 (PRRX2) and the number of immune cells. HCC cell lines were employed to examine the effects of CBS on cellular viability, apoptosis and signaling in vitro. Cbs heterozygous knockout mice, C57BL/6 mice, nude mice and non-obese diabetic severe combined immunodeficiency mice were used to investigate the in vivo functions of CBS.

Results

Downregulation of CBS was observed in HCC, and low expression of CBS predicted poor prognosis in HCC patients. CBS overexpression dramatically promoted cellular apoptosis in vitro and inhibited tumor growth in vivo. Activation of the Cbs/H₂S axis also reduced the abundance of tumor-infiltrating Tregs, while Cbs deficiency promoted Tregs-mediated immune evasion and boosted tumor growth in Cbs heterozygous knockout mice. Mechanistically, CBS facilitated the expression cleaved Caspase-3 in tumor cells, and on the other hand, suppressed Foxp3 expression in Tregs via inactivating IL-6/STAT3 pathway. As a transcription factor of IL-6, PRRX2 was reduced by CBS. Additionally, miR-24-3p was proven to be an upstream suppressor of CBS in HCC.

Conclusions

Our results indicate the antitumor function of CBS in HCC by inactivation of the PRRX2/IL-6/STAT3 pathway, which may serve as a potential target for HCC clinical immunotherapy.

The cis-Regulatory Element of SNCA Intron 4 Modulates Susceptibility to Parkinson's Disease in Han Chinese

Objective: A novel functional cis-regulatory element (CRE) located at SNCA intron 4 has recently been identified in association with Parkinson's disease (PD) risk in European descendants. We aimed to investigate whether this CRE is associated with PD in Han Chinese ethnicity. Methods: A Chinese cohort comprising 513 sporadic PD patients and 517 controls was recruited. CRE variants were identified by sequencing and then analyzed. Results: A total of nine variants were detected, namely eight single nucleotide variants and one new insertion variant. Two variants, rs17016188 and rs7684892, had minor allele frequency greater than 5%. A difference of rs17016188 was observed in males with the C allele serving as a recessive risk factor (p = 0.001, OR = 2.349, 95% CI = 1.414-3.901) following Bonferroni correction. Haplotypes of rs17016188 and rs7684892 showed distribution differences in the total and the male populations (p = 0.002 and 4.08 × 10^-5, respectively). Among the haplotypes, rs17016188/T-rs7684892/G was associated with a reduced risk for PD (p = 4.8 × 10^-4, OR = 0.731, 95% CI = 0.614-0.872). Conclusions: Our results provide insight into how the SNCA intron 4 CRE harbors variants and its contribution to PD risk in Chinese ethnicity.

SLC6A4 Repeat and Single-Nucleotide Polymorphisms Are Associated With Depression and Rest Tremor in Parkinson's Disease: An Exploratory Study

Introduction: Level of serotonin is mainly regulated by the serotonin reuptake transporter encoded by SLC6A4. The promoter region of SLC6A4 bears a repeat polymorphism 5-HTTLPR and a single nucleotide polymorphism rs25531. We have previously studied the association between these two variants and sporadic PD. The objective of the current study was to determine whether the SLC6A4 polymorphisms were associated with key motor and non-motor symptoms of PD.

Methods: A total of 370 PD patients of Han Chinese were included. Associations between the SLC6A4 polymorphisms and PD symptoms including depression, intellectual impairment, tremor and rigidity were analyzed.

Results: 5-HTTLPR was associated with depression in PD patients and presence of the LL genotype was protective against the depression risk. The rs25531 was associated with rest tremor in PD and the A allele serves as a recessive risk allele. No associations were found in the two polymorphisms with respect to intellectual impairment and rigidity in the cohort.

Conclusion: The current study reveals two PD symptoms associated with SLC6A4 polymorphisms, and provides new insight into how serotonergic system genetically participates in the symptomatic progression of PD. Further study is warranted in additional populations.

[Clinical analysis of 10 patients of chronic subdural hematoma associated with arachnoid cyst]

Objective: To investigate the clinical characteristics, pathogenesis and surgical strategy for the chronic subdural hematoma associated with arachnoid cyst (AC). Method: Ten patients of chronic subdural hematoma associated with AC were retrospectively enrolled from the Neurosurgery Department of Tianjin Medical University General Hospital from January 2012 to September 2015, with a mean age of 27.5±5.6 years (range, 18-37 years). All patients simply performed a burr hole drainage of hematoma and left the AC intact, then followed up for 12 to 18 months after discharge respectively. Results: In this study, the AC in 8 of 10 cases occurs in the middle cranial fossa, and the other 2 cases root in the cerebral hemisphere.The AC of 10 patients all locate near the hematoma cavity.Nine patients had a full recovery, and only one patient had a recurrent subdural hematoma with a secondary operation, then recovery in 3 months postoperation.All patients lived completely free of neurological symptom and showed no recurrence in the follow-up period with a Barthel index more than 90. Conclusion: Simply burr hole drainage of hematoma and leave intact AC achieves satisfied outcome and provides a reliable therapy strategy for chronic subdural hematoma associated with arachnoid cyst.

[Application of hybrid operating room in the treatment of spinal dural arteriovenous fistulas]

Objective: To explore the experience in the treatment of spinal dural arteriovenous fistulas with application of hybrid operating room. Method: A retrospective analysis was performed among 22 patients with spinal dural arteriovenous fistulas admitted to Department of Neurosurgery of Tianjin Medical University General Hospital who received operation in the hybrid operating room from March 2011 to February 2016. Modified Aminoff-Logue scores (ALS) for myelopathy was used to evaluate the spinal function.All the 22 patients were followed up 6-12 months after the operation. Result: All the patients were diagnosed by spinal digital subtraction angiography (DSA). The modified ALS pre-operation and post-operation 6 months were (4.7±1.8) and (2.0±1.5), respectively, with significant difference (P<0.01). There were 15 cases with mild dysfunction, 6 cases with moderate dysfunction, severe dysfunction in 1 case before operation.Fifteen cases were cured, 4 cases improved, 1 case had no change after 6 months follow-up.The improvement rate was 95.45%. Conclusion: The application of hybrid operating room in the treatment of spinal dural arteriovenous fistulas achieves good outcome and provides a convenient and effective approach, which embodies the idea of precision medicine.

Eutypenoids A-C: Novel Pimarane Diterpenoids from the Arctic Fungus Eutypella sp. D-1

Eutypenoids A-C (1-3), pimarane diterpenoid alkaloid and two ring A rearranged pimarane diterpenoids, were isolated from the culture of Eutypella sp. D-1 obtained from high-latitude soil of the Arctic. Their structures, including absolute configurations, were authenticated on the basis of the mass spectroscopy (MS), nuclear magnetic resonance (NMR), X-ray crystallography, and electronic circular dichroism (ECD) analysis. The immunosuppressive effects of eutypenoids A-C (1-3) were studied using a ConA-induced splenocyte proliferation model, which suggested that 2 exhibited potent immunosuppressive activities.

Human papillomavirus type 16 E7 peptide(38-61) linked with an immunoglobulin G fragment provides protective immunity in mice

OBJECTIVE

To explore whether the recombinant protein (Human papillomavirus (HPV) type16 E7 peptide(38-61) linked with an immunoglobulin G fragment) will generate protective immunity in mouse model.

METHODS

In our study, we combined the HPV16 E7 peptide(38-61) with a murine IgG heavy chain constant region to construct a chimeric protein compound, which was highly expressed as inclusion bodies in a bacterial expression system with Escherichia coli. The purified chimeric protein was injected into C57BL/6 mice and the efficiency of the chimeric vaccine candidate was evaluated by antibody response assay, T cell proliferation assay, CTL assay, tumor challenge assay and therapeutic experiment.

RESULTS

The chimeric vaccine candidate was able to induce anti-HPV antibodies as well as to elicit HPV16 E7-specific CTLs and T cell proliferation in a pre-clinical mouse model. It was also able to effectively protect mice against the challenge of HPV16-positive tumor cells, and to eradicate HPV16-expressing tumors in mice.

CONCLUSIONS

The chimeric protein vaccine can induce E7-specific immune responses and protect mice against challenge of HPV16-positive tumor, even eradicate developed tumor. The results indicated a possibility to use the chimeric protein vaccine to protect human against HPV infection.

Poly(L-lysine)-modified silica nanoparticles for the delivery of antisense oligonucleotides

Silica nanoparticles were prepared in a microemulsion system, using polyoxyethylene nonylphenyl ether/cyclohexane/ammonium hydroxide. The surface charge of the particle was modified with PLL [poly(L-lysine)]. PAGE demonstrated the ability of PMS-NP (PLL-modified silica nanoparticles) to bind and protect antisense ODNs (oligonucleotides). The intracellular localization of FITC-labelled ODN was investigated by fluorescence microscopy. The results demonstrated that ODN could be delivered to cytoplasm. Flow-cytometry analysis showed a 20-fold enhancement of ODN delivered by PMS-NP compared with free ODN for a serum-free medium. Blocking efficacy of c- myc antisense ODN, delivered by PMS-NP, was examined in HNE1 and HeLa cell lines. Significant down-regulation of c- myc mRNA levels was observed in both the cell lines. However, the cellular uptake efficiency and antisense effects on target gene decreased in the presence of serum-containing medium. The analysis of the filtration assay showed that PMS-NP interacted with serum proteins. These results indicated that PMS-NP was a suitable delivery vector for antisense ODN, although its delivery efficiency decreased in the presence of a serum-containing medium.

BRD7, a novel bromodomain gene, inhibits G1-S progression by transcriptionally regulating some important molecules involved in ras/MEK/ERK and Rb/E2F pathways

Bromodomain is a 110 amino acid domain. It is evolutionally conserved and is found in proteins strongly implicated in signal-dependent transcriptional regulation. BRD7 is a novel bromodomain gene and it is downexpressed in nasopharyngeal carcinoma (NPC) biopsies and cell lines; its function is poorly understood. In the present study, tet-on inducible expression system was used to investigate the role of BRD7 in cell growth and cell cycle progression. We found that ectopic expression of BRD7 in NPC cells inhibited cell growth and cell cycle progression from G1 to S. We further performed cell cycle cDNA array to screen potential transcriptional targets of BRD7 in cell cycle. Thirteen important signaling molecules, mainly implicated in ras/MEK/ERK and Rb/E2F pathways, were differentially expressed by induction of BRD7. Moreover, we observed that BRD7 could regulate the promoter activity of E2F3, one of its targets. Taken together, the present study indicated that BRD7 inhibited G1-S progression by transcriptionally regulating some important molecules involved in ras/MEK/ERK and Rb/E2F pathways and suggested that BRD7 may present a promising candidate of NPC trade mark associated tumor suppressor gene.

[Biocompatibility of poly-l-lysine-modified silica nanoparticles]

BACKGROUND & OBJECTIVE

Poly-l-lysine-modified silica nanoparticle(PMS-NP) was a novel non-viral vector for gene delivery. The current study was designed to evaluate the biocompatibility of PMS-NP for its further utilization in vivo.

METHODS

Cell transfection and flow cytometry were used to elucidate the delivery efficiency of plasmid DNA and antisense ODN mediated by PMS-NP in the presence of serum-containing medium. Subsequently, the biocompatibility of PMS-NP in vivo was evaluated using filtration assay of plasma proteins and erythrocyte aggregation assay.

RESULTS

The abilities of PMS-NP to deliver plasmid DNA and antisense ODN in vitro clearly decreased in the presence of serum-containing medium. PMS-NP/DNA(ODN)complexes bound plasma proteins and triggered erythrocyte aggregation.

CONCLUSION

PMS-NP might interact with plasma proteins, resulting in decreased transfection efficiency in vitro. And filtration assay of plasma proteins and the erythrocyte aggregation assay demonstrated that the interaction of PMS-NP with plasma proteins and erythrocytes might play a negative role in gene transfection efficiency in vivo. And its biocompatibility needs to be further improved.

IONP-PLL: a novel non-viral vector for efficient gene delivery

BACKGROUND

Non-viral methods of gene delivery have been an attractive alternative to virus-based gene therapy. However, the vectors that are currently available have drawbacks limiting their therapeutic application.

METHODS

We have developed a self-assembled non-viral gene carrier, poly-L-lysine modified iron oxide nanoparticles (IONP-PLL), which is formed by modifying poly-L-lysine to the surface of iron oxide nanoparticles. The ability of IONP-PLL to bind DNA was determined by ratio-dependent retardation of DNA in the agarose gel and co-sedimentation assay. In vitro cytotoxic effects were quantified by MTT assay. The transfection efficiency in vitro was evaluated by delivering exogenous DNA to different cell lines using IONP-PLL. Intravenous injection of IONP-PLL/DNA complexes into mice was evaluated as a gene delivery system for gene therapy. The PGL2-control gene encoding firefly luciferase and the EGFP-C2 gene encoding green fluorescent protein were used as marker genes.

RESULTS

IONP-PLL could bind and protect DNA. In contrast to PLL and cationic liposomes, IONP-PLL described here was less cytotoxic in a broad range of concentrations. In the current study, we have demonstrated that IONP-PLL can deliver exogenous gene to cells in vitro and in vivo. After intravenous injection, IONP-PLL transferred reporter gene EGFP-C2 to lung, brain, spleen and kidney. Furthermore, we have demonstrated that IONP-PLL transferred exogenous DNA across the blood-brain barrier to the glial cells and neuron of brain.

CONCLUSIONS

IONP-PLL, a low-toxicity vector, appears to have potential for fundamental research and genetic therapy in vitro and in vivo, especially for gene therapy of CNS disease.

[Analysis of splicing variants in NASG 3'UTR, down-regulated in nasopharyngeal carcinoma, and its expression in multiple cancer tissues]

BACKGROUND & OBJECTIVE

NASG gene, a tissue-specific gene of human nasopharyngeal epithelium was isolated by suppression subtractive hybridization. This study was designed to analyze splicing variants in NASG 3'untranslated region (UTR) and its expression profiling in multiple cancer tissues.

METHODS

The PCR primers were designed in NASG 3'UTR around the splicing variants and reverse transcription-polymerase chain reaction (RT-PCR) was performed. The PCR products were separated and sequenced. The expression patterns of NASG were detected by RT-PCR among nasopharyngeal carcinoma (NPC) cell line HNE1, primary human embryo nasopharyngeal epithelial cells, NPC biopsies, and normal adult nasopharyngeal epithelial tissues. Its expression profiling in multiple cancer tissues were tested by cancer profiling array hybridization.

RESULTS

There were three splicing variants in NASG 3'UTR. NASG was identified to be down-regulated in NPC cell line HNE1 and 71% of the NPC biopsies, but up-regulated in 25% lung of the cancer biopsies, and not express in other cancer tissues and normal tissues.

CONCLUSION

There were three splicing variants in NASG 3'UTR. Its abnormal expression may be an important molecular event in NPC and lung cancer.

[Expression of BRD7-interacting proteins,BRD2 and BRD3, in nasopharyngeal carcinoma tissues]

BACKGROUND & OBJECTIVE

BRD7 is a novel gene tightly associated with nasopharyngeal carcinoma(NPC) cloned by cDNA representational difference analysis (cDNA RDA). Two proteins,BRD2 and BRD3, including bromodomain and interacting with BRD7 protein had been screened from human fetal brain cDNA library by yeast two-hybrid system. This study was designed to further identify the interactions of BRD2 and BRD3 with BRD7 respectively and to investigate the expression and action pattern of BRD2 and BRD3 in NPC.

METHODS

BRD2 and BRD3 genes were respectively co-transformed to yeast Y187 with BRD7 gene, then the yeast cotransformers were blotted to nylon membrane. And then the expression of report gene Lac Z by beta-Gal was determined and the interactions of BRD2 and BRD3 proteins with BRD7 protein were identified. Besides,reverse transcription-polymerase chain reaction (RT- PCR) was used to examine the expression of BRD2 and BRD3 genes in normal nasopharyngeal epithelium and NPC biopsies, and to detect the effect of re-expression of BRD7 gene on the expression of BRD2 and BRD3 genes in HNE1 stably transfected BRD7 gene.

RESULTS

The yeast transformers showed all blue by yeast two-hybrid system, which further identified that BRD2 and BRD3 proteins could respectively interact with BRD7 protein. Down-expression or loss of BRD2 and BRD3 genes were detectable in NPC biopsies. The expression levels of BRD2 and BRD3 were increasing with the re-expression of BRD7 gene in HNE1 stably transfected with BRD7.

CONCLUSION

BRD7 protein could respectively interact with proteins, BRD2 and BRD3, and BRD7 could up-regulate the expression levels of BRD2 and BRD3 genes in mRNA level to some extent. Each of these three homolog proteins might be capable of forming heteromers with the others, which play important roles in the suppression of growth of NPC cells.

Increased interleukin-1beta converting enzyme expression and activity in Alzheimer disease

Increased expression of interleukin-1 in Alzheimer disease (AD) has been implicated as a driving force in neurodegenerative cascades that underlie the formation of neuritic plaques and neurofibrillary tangles, the spread of these neuropathological lesions across cerebral cortical regions, and the accompanying neuronal cell injury and loss. The beta isoform of interleukin-1 is generated from an inactive, 33-kDa precursor through the action of a specific interleukin-1beta converting enzyme (ICE), also known as caspase-1. We used mesial temporal tissue (hippocampus and parahippocampal cortex) obtained postmortem from Alzheimer and control patients for determinations of endogenous tissue ICE activity and for Western immunoblot analysis of tissue ICE concentrations. ICE activity in Alzheimer tissue was elevated 50-100% (p < 0.002, or better, at incubation times of 30 min to 10 h), and ICE protein level was elevated 180% (p = 0.01). Parahippocampal cortex of Alzheimer patients showed increased numbers of neurons with in situ evidence of DNA damage. Increased DNA degradation was also evident upon electrophoresis of isolated DNA. Overexpression and increased activity of ICE may contribute to neurodegeneration in AD through generation of biologically active interleukin-1, with consequent activation of interleukin-1-driven neurodegenerative cascades.

[Porencephaly. A report of 45 cases]

In 45 cases of porencephaly 35 were male and 10 female. Their age ranged from 80 days to 58 years (mean 14 years). In this series, symptoms were observed 80 days to 22 years before diagnosis. twenty-four cases were premature delivery, difficult labour or birth trauma. 14 cases had a history of head injury. 36 cases had congenital porencephalic cyst and 9 had post-traumatic porencephaly. The main symptoms and signs of porencephaly were dementia, speech defect, intracranial hypertension, hydrocephalus, epilepsy, ataxia or paralysis. etc. It is suggested that CT scan is very useful in the diagnosis of porencephaly, and section of cerebral cortex, opening of cyst, continuous drainage or shunting operation should be done as soon as the diagnosis was made.

Preliminary crystallographic analysis of deshexapeptide (B25-B30) insulin

Satisfactory single crystals of deshexapeptide (B25-B30) insulin for X-ray crystal structure analysis have been grown in citrate buffer by the method of hanging-drop gas phase diffusion. The crystal belongs to the monoclinic system with space group C2. The unit cell constants are a = 42.6 A, b = 37.9 A, c = 27.2 A, beta = 125.4 degrees and there is only one molecule of deshexapeptide insulin in an asymmetric unit.

Lamotrigine protects against kainate but not ibotenate lesions in rat striatum

Pretreatment of rats with 8-16 mg/kg of lamotrigine 1 h before intrastriatal injections of 2 nm of kainic acid significantly attenuated the neurotoxicity as evidenced by measurements of striatal choline acetyltransferase and glutamate decarboxylase activities. No significant effect was seen on the toxicity of intrastriatal injections of quinolinic acid or ibotenic acid. These differential effects are further evidence that these neurotoxins act at different excitatory amino acid receptors and that the neurotoxicity of kainate is uniquely dependent on neuronally released glutamate.

Immunostaining of human brain capillaries by antibodies to very late antigens

Normal and neurologically diseased brain tissue was stained with antibodies directed against very late antigens (VLAs) 1, 2, 3, 5, 6, their common beta 1-subunit, and three extracellular proteins: collagen type IV, laminin and fibronectin. Strong staining of capillaries was obtained in both normal and pathological tissue with antibodies to collagen type IV and its putative receptor VLA-1; laminin and its putative receptor VLA-6; and the common VLA beta 1-subunit. Only residual plasma in vessels was stained with the antibody to fibronectin. Negative staining was obtained with antibodies to the fibronectin receptor VLA-5 and VLA-3. Trace staining was obtained with the antibody to VLA-2.

gamma-Glutamyltransferase activity is unchanged in acutely quinolinate-lesioned rat neostriatum but is elevated in Huntington's disease caudate

gamma-Glutamyltransferase (GGT; gamma-glutamyl transpeptidase) was measured in the neostriata of rats 5-7 days after local injections of 0-150 nmol of quinolinic acid. In contrast to the high levels seen in studies on the caudate in a few Huntington's disease cases, GGT activity showed no significant relation to the amount of quinolinic acid injected or to the extent of neuronal loss, as indicated by assays of choline acetyltransferase and glutamate decarboxylase on the same striatal homogenates. The chronicity of the degenerative disease, contrasted with the acuteness of the lesion, may explain the difference.

Effect of MK-801, kynurenate, glycine, dextrorphan and 4-acetylpyridine on striatal toxicity of quinolinate

Measurements of striatal choline acetyltransferase (ChAT) and glutamic acid decarboxylase (GAD) activities indicated that systemic administration of 4-8 mg/kg of MK-801 to rats completely blocked neuronal damage due to intrastriatal injections of 75-150 nmol of quinolinic acid. Similar experiments with 0-2 mg/kg MK-801 suggested the ED50 might be between 1 and 1.5 mg/kg for protection against 50 nmol of intrastriatal quinolinic acid, and between 2 and 3 mg/kg for 75 nmol. Repeated pretreatment with kynurenate (3 x 300 mg/kg) gave significant but not complete protection against similar doses of quinolinic acid, with the protective effect being greater for GAD than for ChAT. Glycine appeared to potentiate the effect of high doses of quinolinic acid on ChAT and the other pretreatments tested (dextrorphan, dextromethorphan, 4-acetylpyridine) had no significant effect.

Gene amplification in Tetrahymena thermophila: formation of extrachromosomal palindromic genes coding for rRNA

Tetrahymena thermophila contains in the macronucleus multiple copies of extrachromosomal palindromic genes coding for rRNA (rDNA) which are generated from a single chromosomal copy during development. In this study we isolated the chromosomal copy of rDNA and determined the structure and developmental fate of the sequence surrounding its 5' junction. The result indicates that specific chromosomal breakage occurs at or near the 5' junction of rDNA during development. The breakage event is associated with DNA elimination and telomeric sequence addition. Similar results were also found previously for the 3' junction of this gene. These results could explain how the extrachromosomal rDNA is first generated. Near both junctions of the chromosomal rDNA, a pair of 20-nucleotide repeats was found. These sequences might serve as signals for site-specific breakage. In addition, we found a pair of perfect inverted repeats at the 5' junction of this gene. The repeats are 42 nucleotides long and are separated by 28 nucleotides. The existence of this structure provides a simple explanation for the formation of the palindromic rDNA.