Photothrombosis combined with thrombin injection establishes a rat model of cerebral venous sinus thrombosis

OBJECTIVE

Cerebral venous sinus thrombosis (CVST) is a rare but life-threatening disease and an animal model for in-depth study of CVST is needed. This study aimed to develop a rat model suitable for studying clinically relevant aspects of CVST and investigating its dynamic pathophysiological changes during a 7-day period.

METHOD

A photothrombosis method was used to create a rat sinus-vein thrombosis model. A spot size-adjustable Diode Pumped Solid State laser (DPSS) combined with thrombin injection occluded the rostral and caudal superior sagittal sinus (SSS). The model was used to evaluate pathophysiological changes at different time points over 7 days. Evans Blue dye injection was used to detect alterations in blood-brain barrier (BBB) permeability. Brain water content was also measured. Moreover, we examined changes in brain infarct volume, neurological function, as well as histology after induction of CVST.

RESULT

CVST in rats significantly altered BBB permeability, consistent with the development of brain edema. It was accompanied by an increase in brain infarct volume and deficits in neurological function that began on day 1, peaked on day 2, and typically improved by day 7 due to the neuroprotective effects of angiogenesis and gliocyte proliferation.

CONCLUSION

In this study, we describe a rat model that produces clinically relevant pathophysiology and pathology that will facilitate evaluation of therapeutic regimens for CVST. Furthermore, our results indicate a period of optimal clinical intervention for patients with CVST, which may reduce the probability of dependency and death.

Evaluation of a viral microarray based on simultaneous extraction and amplification of viral nucleotide acid for detecting human herpesviruses and enteroviruses

In this study, a viral microarray based assay was developed to detect the human herpesviruses and enteroviruses associated with central nervous system infections, including herpes simplex virus type 1, type 2 (HSV1 and HSV2), Epstein-Barr virus (EBV), cytomegalovirus (CMV), enterovirus 71 (EV71), coxsackievirus A 16 (CA16) and B 5(CB5). The DNA polymerase gene of human herpesviruses and 5’-untranslated region of enteroviruses were selected as the targets to design primers and probes. Human herpesviruses DNA and enteroviruses RNA were extracted simultaneously by using a guanidinium thiocyanate acid buffer, and were subsequently amplified through a biotinylated asymmetry multiplex RT-PCR with the specific primer of enteroviruses. In total, 90 blood samples and 49 cerebrospinal fluids samples with suspected systemic or neurological virus infections were investigated. Out of 139 samples, 66 were identified as positive. The specificities of this multiplex RT-PCR microarray assay were over 96% but the sensitivities were various from 100% for HSV1, HSV2, EV71 and CB5, 95.83% for CMV, 80% for EBV to 71.43% for CA16 in comparison with reference standards of TaqMan qPCR/qRT-PCR. The high Kappa values (>0.90) from HSV1, HSV2, CMV, EV71 and CB5 were obtained, indicating almost perfect agreement in term of the 5 viruses detection. But lower Kappa values for EBV (0.63) and CA16 (0.74) displayed a moderate to substantial agreement. This study provides an innovation of simultaneous extraction, amplification, hybridization and detection of DNA viruses and RNA viruses with simplicity and specificity, and demonstrates a potential clinical utility for a variety of viruses’ detection.

Defective autophagy in Parkinson's disease: lessons from genetics

Parkinson's disease (PD) is the most prevalent neurodegenerative movement disorder. Genetic studies over the past two decades have greatly advanced our understanding of the etiological basis of PD and elucidated pathways leading to neuronal degeneration. Recent studies have suggested that abnormal autophagy, a well conserved homeostatic process for protein and organelle turnover, may contribute to neurodegeneration in PD. Moreover, many of the proteins related to both autosomal dominant and autosomal recessive PD, such as α-synuclein, PINK1, Parkin, LRRK2, DJ-1, GBA, and ATPA13A2, are also involved in the regulation of autophagy. We propose that reduced autophagy enhances the accumulation of α-synuclein, other pathogenic proteins, and dysfunctional mitochondria in PD, leading to oxidative stress and neuronal death.

Alpha-synuclein overexpression increases phospho-protein phosphatase 2A levels via formation of calmodulin/Src complex

Alpha-synuclein (α-Syn) is the principal protein component of Lewy bodies, a pathological hallmark of Parkinson's disease (PD). This protein may regulate protein phosphatase 2A (PP2A) activity, although the molecular mechanisms for α-Syn-mediated regulation of PP2A and the potential neuroprotective actions of PP2A against PD-associated pathology remain largely unexplored. We found that α-Syn gene overexpression in SK-N-SH cells and primary neurons led to PP2A/C phosphorylation at Y307, a known target of Src kinase, and consequent phosphatase inhibition. In addition, phospho-activated Src (p-Y416 Src, pSrc) was higher in SK-N-SH cells and primary neurons overexpressing α-Syn. Thus, α-Syn may promote Src activation and PP2A inactivation, leading to hyperphosphorylation of proteins. Immunoprecipitation revealed higher calmodulin/Src complex formation in α-Syn-overexpressing cells and α-Syn transgenic mice. A TUNEL apoptosis assay and an MTT cell viability assay demonstrated that the PP2A activator C2-ceramide protected neurons against α-Syn-induced cell injury. Buffering the Ca(2+) elevations induced by α-Syn overexpression ameliorated the cytotoxicity of α-Syn. Our findings define a potential molecular mechanism for α-Syn-mediated regulation of PP2A through formation of the calmodulin/Src complex, activation of Src, and Src-mediated phospho-inhibition of PP2A. Overexpression of α-Syn may lead to neurodegeneration in PD in part by suppressing the endogenous neuroprotective activity of PP2A.

Identification of differentially expressed genes and pathways between primary osteoarthritis and endemic osteoarthritis (Kashin-Beck disease)

OBJECTIVES

Primary osteoarthritis (OA) and Kashin-Beck disease (KBD) exhibit similar clinical manifestations and common articular cartilage lesions. Revealing the pathogenetic differences between OA and KBD is helpful for differential diagnosis and may provide new insights into the pathogenesis of OA and KBD. In this study, we compared the genome-wide gene ontology (GO) and pathway expression patterns of articular cartilage derived from both OA and KBD patients.

METHODS

Total RNA was isolated, amplified, labelled, and hybridized using Agilent whole genome microarray analysis. Gene set enrichment analysis (GSEA) was used to identify differentially expressed genes and pathways between OA and KBD. Nine differentially expressed GO categories and 85 differentially expressed pathways were identified by this study.

RESULTS

The reactive oxygen species (ROS)-related HOUSTIS_ROS pathway and the vascular endothelial growth factor (VEGF)-related ABE_VEGFA_TARGETS_2HR pathway were significantly up-regulated in OA compared to KBD. Higher expression levels of the collagen-related COLLAGEN GO, EXTRACELLULAR_MATRIX_PART GO, and nitric oxide (NO)-related BIOCARTA_NO1_PATHWAY pathways were detected in KBD than in OA.

CONCLUSIONS

ROS-induced cartilage lesions seem to be more involved in the pathogenesis of OA whereas NO-mediated chondrocyte apoptosis contributes more to the development of KBD.

DJ-1 protects dopaminergic neurons against rotenone-induced apoptosis by enhancing ERK-dependent mitophagy

Loss-of-function mutations in the gene encoding the multifunctional protein, DJ-1, have been implicated in the pathogenesis of early-onset familial Parkinson's disease (PD), suggesting that DJ-1 may act as a neuroprotectant for dopaminergic (DA) neurons. Enhanced autophagy may benefit PD by clearing damaged organelles and protein aggregates; thus, we determined if DJ-1 protects DA neurons against mitochondrial dysfunction and oxidative stress through an autophagic pathway. Cultured DA cells (MN9D) overexpressing DJ-1 were treated with the mitochondrial complex I inhibitor, rotenone. In addition, rotenone was injected into the left substantia nigra of rats 4weeks after injection with a DJ-1 expression vector. Overexpression of DJ-1 protected MN9D cells against apoptosis, significantly enhanced the survival of nigral DA neurons after rotenone treatment in vivo, and rescued rat behavioral abnormalities. Overexpression of DJ-1 enhanced rotenone-evoked expression of the autophagic markers, beclin-1 and LC3II, while transmission electron microscopy and confocal imaging revealed that the ultrastructural signs of autophagy were increased by DJ-1. The neuroprotective effects of DJ-1 were blocked by phosphoinositol 3-kinase and the autophagy inhibitor, 3-methyladenine, and by the ERK pathway inhibitor, U0126. Confocal imaging revealed that the size of p62-positive puncta decreased significantly in DJ-1 overexpression of MN9D cells 12h after rotenone treatment, suggesting that DJ-1 reveals the ability to clear aggregated p62 associated with PD. Factors that control autophagy, including DJ-1, may inhibit rotenone-induced apoptosis and present novel targets for therapeutic intervention in PD.

Altered Aggrecan Synthesis and Collagen Expression Profiles in Chondrocytes from Patients with Kashin—Beck Disease and Osteoarthritis

OBJECTIVES: To investigate cell morphology, aggrecan expression, and type I, II, III and X collagen expression in chondrocytes from adults with Kashin—Beck disease or osteoarthritis (OA). METHODS: Samples of knee articular cartilage were taken during surgery; cartilage samples obtained from fresh cadavers without arthritic disease were used as controls. Samples were digested with collagenase; isolated chondrocytes were cultured in monolayers. Aggrecan was detected by toluidine blue staining; collagen and aggrecan protein levels were evaluated by immuno cytochemistry and immunofluorescence staining. RESULTS: Samples were obtained from six participants per group. Aggrecan and type II collagen levels in chondrocytes from patients were significantly lower than those from controls, but levels of type I, III and X collagen were enhanced in patients compared with controls. Production of type III and X collagen was higher in chondrocytes from patients with Kashin—Beck disease than in those from OA patients. CONCLUSIONS: Biochemical and morphological mechanisms underlying Kashin—Beck disease and OA include enhanced dedifferentiation and hypertrophy of chondrocytes, increased type I, III and X collagen levels, and suppressed type II collagen and aggrecan production compared with control samples.

HPLC-DAD-ESI-MS/MS analysis and antioxidant activities of nonanthocyanin phenolics in mulberry (Morus alba L.)

Qualitative analysis of the nonanthocyanin phenolics from 2 mulberry cultivars, da-10 and hongguo, was performed by the HPLC-DAD-ESI-MS/MS method. Six nonanthocyanin phenolics compounds were identified (procatechuic acid, chlorogenic acid, 4-caffeolyquinic acid, taxifolin, rutin, quercetin) and 3 others (3,5-diCQA, taxifolin-hexoside, kamepferol-hexoside) were tentatively identified. Quantification of nonanthocyanin phenolic was performed by HPLC-DAD, which revealed that rutin (111.38 and 90.79 microg/g FW) was the major nonanthocyanin phenolics in the 2 mulberry cultivars. Phenolic acids in cultivar da-10 (54.68 microg/g FW) were far more than in cultivar hongguo (14.93 microg/g FW). CQA and its isomers (40.02 microg/g FW) were the major phenolic acid in cultivar da-10. The nonanthocyanin phenolics in the 2 cultivars of mulberry had higher antiradical activities in superoxide anion and DPPH radical and antioxidant activity in beta-CLAMS assay than the Trolox. These results were relevant to not only the control of color stability and organoleptic characteristics of mulberry juice and wine but also the exploitation of the functional foods made from mulberry.

Insulin-like growth factor signaling regulates zebrafish embryonic growth and development by promoting cell survival and cell cycle progression

Although much is known about the global effects of insulin-like growth factor 1 receptor (IGF1R)-mediated signaling on fetal growth and the clinical manifestations resulting from IGF/IGF1R deficiencies, we have an incomplete understanding of the cellular actions of this essential pathway during vertebrate embryogenesis. In this study, we inhibited IGF1R signaling during zebrafish embryogenesis using antisense morpholino oligonucleotides or a dominant-negative IGF1R fusion protein. IGF1R inhibition resulted in reduced embryonic growth, arrested development and increased lethality. IGF1R-deficient embryos had significant defects in the retina, inner ear, motoneurons and heart. No patterning abnormalities, however, were found in the brain or other embryonic tissues. At the cellular level, IGF1R inhibition increased caspase 3 activity and induced neuronal apoptosis. Coinjection of antiapoptotic bcl2-like mRNA attenuated the elevated apoptosis and rescued the retinal and motoneuron defects, but not the developmental arrest. Subsequent cell cycle analysis indicated an increased percentage of cells in G1 and a decreased percentage in S phase in IGF1R-deficient embryos independent of apoptosis. These results provide novel insight into the cellular basis of IGF1R function and show that IGF1R signaling does not function as an anteriorizing signal but regulates embryonic growth and development by promoting cell survival and cell cycle progression.

Inhibition of lactate dehydrogenase C4 (LDH-C4) blocks capacitation of mouse sperm in vitro

Lactate dehydrogenase C4 (LDH-C4) is a tissue-specific enzyme in the mammalian testis and the only lactate dehydrogenase isozyme of sperm. Inhibitors of LDH activity were used to determine whether this enzyme plays a role in sperm capacitation, the acrosome reaction and/or fertilization. Oxamate or its derivative was used to inhibit sperm LDH activity in a medium promoting capacitation. Complete inhibition of LDH activity blocked capacitation. This effect could be reversed partially by the addition of dbcAMP or pentoxifylline to the culture medium. Western blotting showed that oxamate and N-isopropyl oxamate inhibited the tyrosine phosphorylation of proteins during the sperm capacitation process. Presumably, glycolysis is the primary energy pathway for sperm metabolism. The oxidation of reduced NAD with the conversion of pyruvate to lactate by LDH provides ATP necessary for protein kinase A (PKA) activity. Our data indicate that LDH-C4 plays an important metabolic role in sperm capacitation.

[Construction of three transgenic vectors carrying the latent membrane protein gene of Epstein-Barr virus]

In order to produce transgenic mice carrying the latent membrane protein(LMP) gene of Epstein-Barr virus(EBV) and to study the oncogenic role of LMP gene in vivo, three different transgenic vectors carrying the LMP gene were constructed. In pBR322-MT-LMP vector, the promoter of LMP gene is the regulation region of mouse metallothionein-I gene. In pMci3-LMP shuttle vector, the promoter of LMP gene is the replication origin(oriP) of EBV. In pMV-LMP-c-myc retroviral vector, the long terminal repeat (LTR) of mouse sarcomavirus serves as the promoter of LMP gene. The characterization and usefulness of these three transgenic vectors are also discussed.

Specifying the cellular responses to IGF signals: roles of IGF-binding proteins

Regulation of peptide growth factor/hormone activities by secreted hormone-binding proteins has emerged as a common theme in cell-cell signaling. Among the best-studied examples are members of the IGF-binding protein (IGFBP) gene family. These secreted proteins bind the IGF ligands with equal or even greater affinities than do the IGF receptors, and therefore are placed in a critical regulatory position between IGFs and their cell surface receptors. The circulating IGF/IGFBP complexes prolong the half-lives of IGFs and buffer the potential hypoglycemic effects of IGFs. Locally expressed IGFBPs provide a means of localizing IGFs in specific cells and can alter the IGF biological activity. While some members of the IGFBP gene family have been consistently shown to inhibit IGF actions by preventing them from gaining access to the IGF receptors, others potentiate IGF actions by facilitating the ligand-receptor interaction. Furthermore, recent studies indicate that some IGFBPs can regulate several cellular processes through ligand-independent mechanisms. This review will focus on the roles of IGFBPs in vascular smooth muscle cells. A conceptual model of the molecular mechanisms by which IGFBPs act to determine the specific physiological outcomes of IGF stimulation is proposed and discussed.

Ontogeny, tissue distribution, and hormonal regulation of insulin-like growth factor binding protein-2 (IGFBP-2) in a marine fish, Sparus aurata

In this study, we have cloned insulin-like growth factor binding protein (IGFBP)-2 from a marine hermaphroditic fish species, the gilthead sea bream (Sparus aurata), and determined its structure, ontogeny, tissue distribution, and hormonal regulation. The sea bream IGFBP-2 precursor consists of 286 amino acids, including a putative signal peptide of 22 residues and a mature protein of 264 residues. The overall sequence of sea bream preIGFBP-2 is 52-39% identical to that of zebrafish, chick, mouse, rat, pig, sheep, bovine, and human preIGFBP-2. The cysteine-rich N- and C-terminal domains, which are believed to be important for IGF binding, show a greater degree of conservation with a sequence identity of 73-56% and 53-50%, respectively. Sea bream IGFBP-2 contains 18 cysteine residues and their alignment is identical to those of other vertebrate IGFBP-2s. The Arg-Gly-Asp (RGD) sequence, present in the C-terminal domain of all known IGFBP-2, is also present in the sea bream. Northern blot analysis of RNA samples extracted from adult liver and developing larvae, revealed two transcripts of about 1.3 and 2.5 kb. RT-PCR analysis showed that IGFBP-2 was expressed in all adult tissues studied, with the highest levels found in liver and skin. IGFBP-2 transcripts were detected in gonad during reproductive cycle of S. aurata. Highest levels of IGFBP-2 mRNA were found in bisexual young gonads, and the levels decreased with gonad development and relatively high levels of IGFBP-2 mRNA were found in the ovary during spawning. By contrast, testicular IGFBP-2 mRNA levels were very low. RT-PCR detected IGFBP-2 mRNA throughout development in unfertilized eggs, embryos, and larvae, with highest levels observed after day 3 post-hatching, suggesting that this mRNA is the product of both the maternal and embryonic genomes. High variability in steady-state levels of hepatic IGFBP-2 mRNA was noted in adult fish, resulting in a statistically insignificant response to growth hormone treatment. These results suggest that the structure of IGFBP-2 is conserved in sea bream and that IGFBP-2 mRNA is expressed during early development and in gonad during the reproductive cycle, suggesting that it may play a role in gilthead sea bream development and reproduction.

Construction of a square-planar molecular box: self-assembly of palladium(II) complexes of 3,6,9,16,19,22-hexaazatricyclo[22.2.2.2(11,14)]triacon-11,13,24,26(1),27,29-hexaene through hydrogen-bonding interactions

Binuclear palladium(II) complexes of the macrocyclic polyamine 3,6,9,16,19,22-hexaazatricyclo[22.2.2.2(11,14)]triacon-11,13,24,26(1),2 7,29-hexaene (L) are used to construct molecules having special shapes. In this study two binuclear palladium(II) complexes [Pd(2)LI(2)]I(2)and [Pd(2)LCl(2)](NO(3))(2).H(2)O are synthesized and structurally characterized. X-ray crystallography shows that both complexes exist as one-dimensional chains formed via intermolecular hydrogen-bonding N(3)-H(3C)---X in which X is I and Cl. Moreover, the ligands in both complexes adopt a boatlike conformation that may facilitate the formation of the tetranuclear complex. The cationic aqua complex [Pd(2)L(H(2)O)(m)(NO(3))(n)]((4-n)+, obtained by the treatment of [Pd(2)LI(2)]I(2)and [Pd(2)LCl(2)]Cl(2) with AgNO(3), is used as a building block for the construction of a tetranuclear palladium(II) complex [Pd(4)L(2)(C(2)O(4))(2)](NO(3))(4).6H(2)O. X-ray crystallography shows that the tetranuclear complex forms an open, hydrophobic box. These molecular boxes are connected via the hydrogen bond N(3)-H(3C)---O(4B) (symmetry code B: x, 1 + y, z) into a one-dimensional chain. A two-dimensional structure is formed via pi-pi stacking of the plane defined by C6 to C11 in the one chain and its symmetry-related plane (symmetry code C: -x, -1 - y, 2 - z) in another chain. This study exemplifies a new method for the assembly of molecular boxes using a macrocyclic ligand.

Inhibition of purified recombinant reverse transcriptase from wild-type and zidovudine-resistant clinical isolates of human immunodeficiency virus type 1 by zidovudine, stavudine, and lamivudine triphosphates

Cross-resistance between zidovudine, stavudine, and lamivudine was studied, using purified recombinant reverse transcriptase from a zidovudine-susceptible and -resistant pair of clinical isolates of human immunodeficiency virus type 1. The zidovudine-resistant isolate exhibited low-level cross-resistance to both stavudine and lamivudine in drug susceptibility assays. Enzyme from the resistant isolate demonstrated reduced inhibition by zidovudine triphosphate and stavudine triphosphate and, to a lesser extent, lamivudine triphosphate. These findings provide additional evidence at the viral and enzyme level for cross-resistance between zidovudine and stavudine, and they suggest a possible effect of zidovudine resistance on susceptibility to lamivudine.

Biochemical and functional analysis of a conserved IGF-binding protein isolated from rainbow trout (Oncorhynchus mykiss) hepatoma cells

Rainbow trout (Oncorhynchus mykiss) serum contains several IGF-binding proteins (IGFBPs) that specifically bind to IGFs. The structures of these fish IGFBPs have not been determined and their physiological functions are poorly defined. In this study, we identified a 30 kDa IGFBP present in rainbow trout serum and secreted by cultured trout hepatoma cells. This IGFBP binds to IGFs but not to insulin. This IGFBP was purified to homogeneity using a three-step procedure involving Phenyl-Sepharose chromatography, IGF-I affinity chromatography and reverse-phase HPLC. Affinity cross-linking studies indicated that this IGFBP binds to IGF-I with a higher affinity than to IGF-II. N-terminal sequence analysis of the trout IGFBP suggests that it shares high sequence identity with that of human IGFBP-1 in the N-terminal region. When added to cultured fish and human cells, the trout IGFBP inhibited IGF-I-stimulated DNA synthesis and cell proliferation in a concentration-dependent manner. The inhibitory effect of the fish IGFBP was comparable to those of human IGFBP-1 and -4. These results indicate that the IGFBP molecule is structurally and functionally conserved in evolutionarily ancient vertebrate species such as bony fish.

[On the characteristics of velocity modulation laser spectroscopy]

The technical properties of velocity modulation laser spectroscopy were investigated using the spectrum of A2 pi u-X2 sigma g+ (2-0) band of Meinel system of N2+. The dependence of spectral intensity on discharge current, the pressure of the gas mixture and the pump velocity of the vacuum pump were studied. Making uses of the results of these studies, the sensitivity and resolution of the spectrometer are improved by above 3 times, and economized the experimental expenses can be reduced to as 3/4 time as normal, which confirms that the results of this paper is of considerable uses.

[Short-term and long-term effectiveness of endovascular embolization in treating intracranial aneurysms]

OBJECTIVE

To study the short-term and long-term effectiveness of endovascular embolization with Guglielmi detachable coil (GDC) or mechanical detachable spiral (MDS) intreating intracranial aneurysms.

METHODS

362 patients with cerebral aneurysms were treated by endovascular embolization with GDC or MDS. Follow-up interviews in the form of correspondence or hospital visit were conducted to 173 of those patients 3 approximately 24 months after the treatment. DSA cerebral artery angiography was made to 84 patients.

RESULTS

The clinical symptoms disappeared gradually after the treatment among all of the interviews. No subarchnoid hemorrhage was found. All of the 56 cases with ocular paralysis recovered, 1 case in a week, 52 in a year, and 3 in 18 months. Visual acuity improved to different degrees among 10 cases with visual disturbance in 6 months. Five of the 84 patients who received DSA angiography showed recurrence of aneurysm. Then cause of recurrence was absorption of MDS coils in 2 cases and shifting of the coil in 3 case.

CONCLUSIONS

Endovascular embolization is an effective method in treating the intracranial aneurysms with minimal invasiveness and few complications.