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1.
Sci Rep ; 10(1): 6782, 2020 Apr 22.
Article in English | MEDLINE | ID: mdl-32321964

ABSTRACT

Solution-processed metal grid transparent conductors with low sheet resistance, high optical transmittance and good mechanical flexibility have great potential for use in flexible optoelectronic devices. However, there are still remaining challenges to improve optoelectrical properties and electromechanical stability of the metallic structures due to random loose packings of nanoparticles and the existence of many pores. Here we introduce a selective multi-nanosoldering method to generate robust metallic layers on the thin metal grid structures (< a thickness of 200 nm), which are generated via self-pining assisted direct inking of silver ions. The selective multi-nanosoldering leads to lowering the sheet resistance of the metal grid transparent conductors, while keeping the optical transmittance constant. Also, it reinforces the electromechanical stability of flexible metal grid transparent conductors against a small bending radius or a repeated loading. Finally, organic light-emitting diodes based on the flexible metal grid transparent conductors are demonstrated. Our approach can open a new route to enhance the functionality of metallic structures fabricated using a variety of solution-processed metal patterning methods for next-generation optoelectronic and micro/nanoelectronic applications.

2.
Eur J Neurol ; 27(2): 258-264, 2020 02.
Article in English | MEDLINE | ID: mdl-31446637

ABSTRACT

BACKGROUND AND PURPOSE: High uric acid (UA) levels have been shown to exert a neuroprotective effect in Parkinson's disease (PD) by inhibiting oxidative stress in the nigrostriatal pathway. However, the association between striatal dopamine activity and UA level has not been clarified. METHODS: A total of 213 patients with early PD were enrolled. All patients underwent positron emission tomography using 18 F-N-(3-fluoropropyl)-2beta-carbon ethoxy-3beta-(4-iodophenyl) nortropane and a venous blood test for quantification of serum UA. All patients were stratified into either the lower UA group or the higher UA group using the median UA level. After normalizing the positron emission tomography images, differences in the regional standardized uptake value ratios (SUVRs) were analyzed with a volume-of-interest template. All tested SUVRs were also compared after categorizing patients by gender. RESULTS: The UA affected dopamine transporter SUVRs in different ways by gender. In female patients, the higher UA level group showed a smaller reduction in dopamine transporter uptake in the posterior putamen, whereas there was no such association observed in male patients. CONCLUSIONS: Higher UA levels were correlated with higher dopamine transporter uptake in the putamen in female patients with early PD. This finding suggests that UA has a neuroprotective effect, as demonstrated by the relatively preserved striatal dopamine activity in women.


Subject(s)
Corpus Striatum/metabolism , Dopamine/metabolism , Parkinson Disease/metabolism , Uric Acid/metabolism , Aged , Aged, 80 and over , Corpus Striatum/diagnostic imaging , Dopamine Plasma Membrane Transport Proteins/metabolism , Female , Humans , Male , Middle Aged , Neuroprotective Agents , Parkinson Disease/diagnostic imaging , Positron-Emission Tomography , Putamen/metabolism , Sex Characteristics , Uric Acid/blood
4.
Eur J Neurol ; 24(2): 349-356, 2017 02.
Article in English | MEDLINE | ID: mdl-27888574

ABSTRACT

BACKGROUND AND PURPOSE: Reduction of metaiodobenzylguanidine (MIBG) uptake has been observed in almost all patients with Parkinson's disease (PD), associated with hyposmia, orthostatic hypotension and rapid eye movement sleep behavioral disorder (RBD). In contrast, a subgroup of patients with PD with normal MIBG uptake have been reported to have milder disease and preserved cognition compared with those with lower MIBG. The aim of this study was to investigate whether non-motor manifestations of PD differ between patients with normal and abnormal myocardial MIBG uptake. METHODS: Among 160 de-novo cases of PD, 44 had normal MIBG uptake. Twelve candidate non-motor features were evaluated using questionnaires and laboratory tests. RESULTS: Patients with decreased MIBG uptake had more constipation, RBD, cognitive impairment, hyposmia and orthostatic hypotension than did those with normal MIBG uptake. On linear regression analysis, orthostatic hypotension, olfactory function and probable RBD were significantly associated with MIBG uptake in PD. The principal component analysis showed that the group with normal MIBG was not associated with non-motor impairments. CONCLUSIONS: These results suggest that patients with PD with normal MIBG scans have a relatively low disease burden compared with those with abnormal MIBG. Fewer synuclein pathologies in the myocardia and sympathetic ganglia in PD with preserved MIBG uptake might be associated with lower threshold patterns of Braak synuclein pathology for non-motor manifestations compared with PD with decreased MIBG.


Subject(s)
Heart/diagnostic imaging , Parkinson Disease/diagnostic imaging , 3-Iodobenzylguanidine/metabolism , Aged , Cognition Disorders/etiology , Cognition Disorders/psychology , Constipation/etiology , Cost of Illness , Female , Humans , Hypotension, Orthostatic/etiology , Hypotension, Orthostatic/physiopathology , Male , Middle Aged , Olfaction Disorders/etiology , Olfaction Disorders/physiopathology , Parkinson Disease/complications , Positron-Emission Tomography , REM Sleep Behavior Disorder/etiology , Radiopharmaceuticals/metabolism
5.
J Phys Condens Matter ; 28(50): 505304, 2016 12 21.
Article in English | MEDLINE | ID: mdl-27792666

ABSTRACT

Electric field effect (EFE) controlled magnetoelectric transport in thin films of undoped and La-doped Sr2IrO4 (SIO) is investigated using ionic liquid gating. The temperature dependent resistance measurements exhibit insulating behavior in chemically and EFE doped samples with the band filling up to 10%. The ambipolar transport across the Mott gap is demonstrated by EFE tuning of the channel resistance and chemical doping. We observe a crossover from high temperature negative to low temperature positive magnetoresistance around ∼80-90 K, irrespective of the filling. This temperature and magnetic field dependent crossover is discussed in the light of conduction mechanisms of SIO, especially variable range hopping (VRH), and its relevance to the insulating ground state of SIO.

6.
Dis Esophagus ; 29(6): 642-8, 2016 Aug.
Article in English | MEDLINE | ID: mdl-26382588

ABSTRACT

Patients with non-metastatic esophageal cancer routinely undergo endoscopic ultrasound (EUS) for loco-regional staging. Neoadjuvant therapy is recommended for ≥T3 tumors while upfront surgery can be considered for ≤T2 lesions. The aim of this study was to determine if the degree of dysphagia can predict the EUS T-stage of esophageal cancer. One hundred eleven consecutive patients with non-metastatic esophageal cancer were retrospectively reviewed from a database. Prior to EUS, patients' dysphagia grade was recorded. Correlation between dysphagia grade and EUS T-stage, especially in reference to predicting ≥T3 stage, was determined. The correlation of dysphagia grade with EUS T-stage (Kendall's tau coefficient) was 0.49 (P < 0.001) for the lower and 0.59 (P = 0.008) for the middle esophagus. The sensitivity and specificity of dysphagia grade ≥2 (can only swallow semi-solids/liquids) for T3 cancer were 56% (95% confidence interval [CI] 43-67%) and 93% (95% CI 79-98%), respectively. The sensitivity, specificity, and positive predictive value of dysphagia grade ≥3 (can only swallow liquids or total dysphagia) for T3 lesions were 36% (95% CI 25-48%), 100% (95% CI 89-100%), and 100% (95% CI 83-100%), respectively. Overall, there was a significant positive correlation between dysphagia grade and the EUS T-stage of esophageal cancer. All patients with dysphagia grade ≥3 had T3 lesions. This may have clinical implications for patients who can only swallow liquids or have complete dysphagia by allowing for prompt initiation of neoadjuvant therapy, especially in countries/centers where EUS service is difficult to access in a timely manner or not available.


Subject(s)
Adenocarcinoma/complications , Carcinoma, Adenosquamous/complications , Carcinoma, Squamous Cell/complications , Deglutition Disorders/etiology , Esophageal Neoplasms/complications , Adenocarcinoma/diagnostic imaging , Adenocarcinoma/pathology , Adult , Aged , Aged, 80 and over , Carcinoma, Adenosquamous/diagnostic imaging , Carcinoma, Adenosquamous/pathology , Carcinoma, Squamous Cell/diagnostic imaging , Carcinoma, Squamous Cell/pathology , Endosonography , Esophageal Neoplasms/diagnostic imaging , Esophageal Neoplasms/pathology , Female , Humans , Lymph Nodes/diagnostic imaging , Lymph Nodes/pathology , Male , Middle Aged , Neoplasm Staging , Retrospective Studies , Severity of Illness Index
7.
Andrologia ; 48(3): 325-32, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26148765

ABSTRACT

Cubilin (cubn) is a receptor for vitamins and various protein ligands. Cubn lacks a transmembrane domain but anchors to apical membranes by forming complexes with Amnionless or Megalin. In an effort to better understand the uptake of nutrients in testis, we analysed cubn expression in the developing mice testes. In testes, cubn mRNA increased from birth to adulthood. In the inter-stitium and isolated seminiferous tubules, neonatal increase in cubn mRNA until 14 days post-partum (pp) was followed by a marked increase at puberty (28 days pp). Cubn was found in the gonocytes, spermatogonia, spermatocytes and spermatids in the developing testes. In adult testes, strong Cubn immunoreactivity was found in the elongating spermatids, suggesting the role of Cubn in endocytosis during early spermiogenesis. In Sertoli cells and peritubular cells, Cubn immunoreactivity was weak throughout the testis development. In the inter-stitium, Cubn immunoreactivity was found in foetal Leydig cells, was weak to negligible in the stem cells and progenitor Leydig cells and was strong in immature and adult Leydig cells, demonstrating a positive association between Cubn and steroidogenic activity of Leydig cells. Collectively, these results suggest that Cubn may participate in the endocytotic uptake of nutrients in germ cells and somatic cells, supporting the spermatogenesis and steroidogenesis in mouse testes.


Subject(s)
Leydig Cells/metabolism , Receptors, Cell Surface/metabolism , Seminiferous Tubules/metabolism , Spermatogenesis/genetics , Testis/metabolism , Animals , Male , Mice , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptors, Cell Surface/genetics , Spermatids/metabolism , Spermatocytes/metabolism , Spermatogonia/metabolism
9.
Phys Rev Lett ; 115(13): 137201, 2015 Sep 25.
Article in English | MEDLINE | ID: mdl-26451580

ABSTRACT

We report the discovery of a metamagnetic phase transition in a polar antiferromagnet Ni_{3}TeO_{6} that occurs at 52 T. The new phase transition accompanies a colossal magnetoelectric effect, with a magnetic-field-induced polarization change of 0.3 µC/cm^{2}, a value that is 4 times larger than for the spin-flop transition at 9 T in the same material, and also comparable to the largest magnetically induced polarization changes observed to date. Via density-functional calculations we construct a full microscopic model that describes the data. We model the spin structures in all fields and clarify the physics behind the 52 T transition. The high-field transition involves a competition between multiple different exchange interactions which drives the polarization change through the exchange-striction mechanism. The resultant spin structure is rather counterintuitive and complex, thus providing new insights on design principles for materials with strong magnetoelectric coupling.

10.
Mol Psychiatry ; 20(12): 1546-56, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26370144

ABSTRACT

Mood disorders and antidepressant therapy involve alterations of monoaminergic and glutamatergic transmission. The protein S100A10 (p11) was identified as a regulator of serotonin receptors, and it has been implicated in the etiology of depression and in mediating the antidepressant actions of selective serotonin reuptake inhibitors. Here we report that p11 can also regulate depression-like behaviors via regulation of a glutamatergic receptor in mice. p11 directly binds to the cytoplasmic tail of metabotropic glutamate receptor 5 (mGluR5). p11 and mGluR5 mutually facilitate their accumulation at the plasma membrane, and p11 increases cell surface availability of the receptor. Whereas p11 overexpression potentiates mGluR5 agonist-induced calcium responses, overexpression of mGluR5 mutant, which does not interact with p11, diminishes the calcium responses in cultured cells. Knockout of mGluR5 or p11 specifically in glutamatergic neurons in mice causes depression-like behaviors. Conversely, knockout of mGluR5 or p11 in GABAergic neurons causes antidepressant-like behaviors. Inhibition of mGluR5 with an antagonist, 2-methyl-6-(phenylethynyl)pyridine (MPEP), induces antidepressant-like behaviors in a p11-dependent manner. Notably, the antidepressant-like action of MPEP is mediated by parvalbumin-positive GABAergic interneurons, resulting in a decrease of inhibitory neuronal firing with a resultant increase of excitatory neuronal firing. These results identify a molecular and cellular basis by which mGluR5 antagonism achieves its antidepressant-like activity.


Subject(s)
Annexin A2/metabolism , Depression/etiology , Receptor, Metabotropic Glutamate 5/metabolism , S100 Proteins/metabolism , Animals , GABAergic Neurons/metabolism , Glutamic Acid/metabolism , HEK293 Cells , Humans , Mice , Mice, Inbred C57BL , Neural Inhibition , Neurons/metabolism , Parvalbumins/metabolism , Receptor, Metabotropic Glutamate 5/antagonists & inhibitors , Signal Transduction , Synapses
11.
AJNR Am J Neuroradiol ; 36(9): 1642-7, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26228888

ABSTRACT

BACKGROUND AND PURPOSE: The burden of amyloid ß is greater in patients with dementia with Lewy bodies than in those with Parkinson disease dementia, and an increased amyloid ß load is closely related to a higher incidence of cerebral microbleeds. Here, we investigated the prevalence and topography of cerebral microbleeds in patients with dementia with Lewy bodies and those with Parkinson disease dementia to examine whether cerebral microbleeds are more prevalent in patients with dementia with Lewy bodies than in those with Parkinson disease dementia. MATERIALS AND METHODS: The study population consisted of 42 patients with dementia with Lewy bodies, 88 patients with Parkinson disease dementia, and 35 controls who underwent brain MR imaging with gradient recalled-echo. Cerebral microbleeds were classified as deep, lobar, or infratentorial. RESULTS: The frequency of cerebral microbleeds was significantly greater in patients with dementia with Lewy bodies (45.2%) than in those with Parkinson disease dementia (26.1%) or in healthy controls (17.1%; P = .017). Lobar cerebral microbleeds were observed more frequently in the dementia with Lewy bodies group (40.5%) than in the Parkinson disease dementia (17%; P = .004) or healthy control (8.6%; P = .001) group, whereas the frequencies of deep and infratentorial cerebral microbleeds did not differ among the 3 groups. Logistic regression analyses revealed that, compared with the healthy control group, the dementia with Lewy bodies group was significantly associated with the presence of lobar cerebral microbleeds after adjusting for age, sex, nonlobar cerebral microbleeds, white matter hyperintensities, and other vascular risk factors (odds ratio, 4.39 [95% CI, 1.27-15.25]). However, compared with the healthy control group, the Parkinson disease dementia group was not significantly associated with lobar cerebral microbleeds. CONCLUSIONS: This study showed that patients with dementia with Lewy bodies had a greater burden of cerebral microbleeds and exhibited a lobar predominance of cerebral microbleeds than did patients with Parkinson disease dementia.


Subject(s)
Cerebral Hemorrhage/epidemiology , Cerebral Hemorrhage/pathology , Lewy Body Disease/complications , Parkinson Disease/complications , Aged , Amyloid beta-Peptides/analysis , Cerebral Hemorrhage/etiology , Female , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Odds Ratio , Prevalence , Risk Factors
12.
Exp Clin Endocrinol Diabetes ; 123(4): 221-6, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25502579

ABSTRACT

BACKGROUND: In this study, we investigated whether Smad4 signaling is involved in the regulation of beta-cell function using a high fat diet (HFD)-induced obesity mouse model. METHODS: Beta-cell-specific Smad4-knockout mice (Smad4(-/-)RIP-Cre(+); ß-Smad4KO) were generated by mating Smad4 (flox/flox) mice with rat insulin promoter (RIP)-Cre mice. Mice were fed a HFD beginning at 6 weeks of age for 16 weeks. Body weight, food intake, fasting and fed glucose levels, and glucose and insulin tolerance were measured. RESULTS: The expression of Smad4 mRNA was significantly decreased in the islets of ß-Smad4KO mice. In wild-type mice, Smad4 mRNA was significantly decreased at 18 weeks of age as compared with 8 weeks of age. On a regular chow diet, ß-Smad4KO mice showed no differences in body weight, fed and fasting blood glucose levels, and glucose tolerance compared with wild-type mice. When fed a HFD, body weight gain was significantly reduced in ß-Smad4KO mice as compared with wild-type mice, although the amount of food intake was not different. During the HFD, fed and fasting blood glucose levels, glucose stimulated insulin secretion, disposition index and glucose tolerance were significantly improved in ß-Smad4KO mice as compared with wild-type mice. However, insulin tolerance tests showed no differences between the 2 groups. CONCLUSION: Inhibition of Smad4 in beta-cells conferred mild but significant improvements in glucose levels and glucose tolerance in HFD-induced obese mice. Therefore, regulation of Smad4 expression may be one of the mechanisms regulating physiological expansion of beta-cells during development of type 2 diabetes.


Subject(s)
Diet, High-Fat , Glucose Intolerance/metabolism , Insulin-Secreting Cells/metabolism , Obesity/metabolism , Smad4 Protein/metabolism , Animals , Blood Glucose/metabolism , Body Weight/physiology , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/metabolism , Glucose Intolerance/etiology , Glucose Intolerance/genetics , Glucose Tolerance Test , Insulin/blood , Insulin Resistance , Male , Mice , Mice, Knockout , Obesity/etiology , Obesity/genetics , Smad4 Protein/genetics
13.
Phys Rev Lett ; 111(1): 017202, 2013 Jul 05.
Article in English | MEDLINE | ID: mdl-23863023

ABSTRACT

Structural and magnetic chiralities are found to coexist in a small group of materials in which they produce intriguing phenomenologies such as the recently discovered Skyrmion phases. Here, we describe a previously unknown manifestation of this interplay in MnSb(2)O(6), a trigonal oxide with a chiral crystal structure. Unlike all other known cases, the MnSb(2)O(6) magnetic structure is based on corotating cycloids rather than helices. The coupling to the structural chirality is provided by a magnetic axial vector, related to the so-called vector chirality. We show that this unique arrangement is the magnetic ground state of the symmetric-exchange Hamiltonian, based on ab initio theoretical calculations of the Heisenberg exchange interactions, and is stabilized by out-of-plane anisotropy. MnSb(2)O(6) is predicted to be multiferroic with a unique ferroelectric switching mechanism.

14.
Phys Rev Lett ; 110(21): 217206, 2013 May 24.
Article in English | MEDLINE | ID: mdl-23745922

ABSTRACT

Magnetic domains at the surface of a ferroelectric monodomain BiFeO(3) single crystal have been imaged by hard x-ray magnetic scattering. Magnetic domains up to several hundred microns in size have been observed, corresponding to cycloidal modulations of the magnetization along the wave vector k=(δ,δ,0) and symmetry equivalent directions. The rotation direction of the magnetization in all magnetic domains, determined by diffraction of circularly polarized light, was found to be unique and in agreement with predictions of a combined approach based on a spin-model complemented by relativistic density-functional simulations. Imaging of the surface shows that the largest adjacent domains display a 120° vortex structure.

15.
Eur J Obstet Gynecol Reprod Biol ; 169(2): 366-9, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23664457

ABSTRACT

OBJECTIVE: To compare surgical outcomes and complications between single-port access (SPA) and multi-port access (MPA) laparoscopy-assisted vaginal hysterectomy (LAVH). STUDY DESIGN: A retrospective review of medical records was performed in patients who underwent LAVH for non-malignant gynaecological diseases at Eun Hospital between April 2010 and April 2012. One hundred and twenty women underwent SPA LAVH using a transumbilical three-channel single-port system and 130 women underwent conventional MPA LAVH. Surgical outcomes and complications were compared between the two groups. RESULTS: The outcomes of the SPA-LAVH group vs. the conventional MPA-LAVH group were as follows: mean±standard deviation total operative time (73.1±24.3 vs. 70.3±22.1min, p=0.349), largest dimension of uterus (10.7±2.3 vs. 10.8±2.8cm, p=0.847), weight of extirpated uterus (311±185 vs. 339±234g, p=0.298) and change in haemoglobin (1.7±0.8 vs. 2.0±0.9g/dl, p=0.025). The incidence of complications was similar in each group (20 vs. 16 patients, p=0.327). Unplanned intra-operative laparotomy was not necessary in either group, and there were no cases of bowel injury or main vessel injury in either group. In total, there were three bladder injuries: one in the SPA-LAVH group and two in the MPA-LAVH group. The postoperative course was uneventful in most patients, but six patients had a transient paralytic ileus (four in the SPA-LAVH group and two in the MPA-LAVH group) and 10 patients had a pelvic haematoma (five in each group), all of whom recovered following conservative management. Port-related complications were rare, but one patient in the SPA-LAVH group had a port-site umbilical hernia. CONCLUSION: Use of SPA and MPA LAVH has similar results in terms of surgical outcomes and complications.


Subject(s)
Hysterectomy, Vaginal/methods , Laparoscopy/methods , Adult , Aged , Female , Humans , Hysterectomy, Vaginal/adverse effects , Hysterectomy, Vaginal/statistics & numerical data , Laparoscopy/adverse effects , Laparoscopy/statistics & numerical data , Middle Aged , Retrospective Studies , Treatment Outcome
16.
Oncogene ; 32(41): 4873-82, 2013 Oct 10.
Article in English | MEDLINE | ID: mdl-23160379

ABSTRACT

Claudins (CLDNs) are a family of integral membrane proteins central to the formation of tight junctions, structures that are involved in paracellular transport and cellular growth and differentiation, and are critical for the maintenance of cellular polarity. Recent studies have provided evidence that CLDNs are aberrantly expressed in diverse types of human cancers, including hepatocellular carcinomas (HCCs). However, little is known about how CLDN expression is involved in cancer progression. In this study, we show that CLDN1 has a causal role in the epithelial-mesenchymal transition (EMT) in human liver cells, and that the c-Abl-Ras-Raf-1-ERK1/2 signaling axis is critical for the induction of malignant progression by CLDN1. Overexpression of CLDN1 induced expression of the EMT-regulating transcription factors Slug and Zeb1, and thereby led to repression of E-cadherin, ß-catenin expression, enhanced expression of N-cadherin and Vimentin, a loss of cell adhesion, and increased cell motility in normal liver cells and HCC cells. In line with these findings, inhibition of either c-Abl or ERK clearly attenuated CLDN1-induced EMT, as evidenced by a reversal of N-cadherin and E-cadherin expression patterns, and restored normal motility. Collectively, these results indicate that CLDN1 is necessary for the induction of EMT in human liver cells, and that activation of the c-Abl-Ras-Raf-1-ERK1/2 signaling pathway is required for CLDN1-induced acquisition of the malignant phenotype. The present observations suggest that CLDN1 could be exploited as a biomarker for liver cancer metastasis and might provide a pivotal point for therapeutic intervention in HCC.


Subject(s)
Claudin-1/metabolism , Epithelial-Mesenchymal Transition , Extracellular Signal-Regulated MAP Kinases/metabolism , Liver Neoplasms/pathology , Liver/pathology , Proto-Oncogene Proteins c-abl/metabolism , Signal Transduction , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Gene Expression Regulation, Neoplastic , Homeodomain Proteins/metabolism , Humans , Liver/metabolism , Liver Neoplasms/metabolism , Neoplasm Invasiveness , Proto-Oncogene Proteins c-raf/metabolism , Snail Family Transcription Factors , Tight Junctions/metabolism , Transcription Factors/metabolism , Zinc Finger E-box-Binding Homeobox 1 , ras Proteins/metabolism
17.
Andrologia ; 45(6): 363-8, 2013 Dec.
Article in English | MEDLINE | ID: mdl-22998388

ABSTRACT

Glycan epitopes of cellular glycoconjugates act as versatile biochemical signals, and this sugar coding plays an important role in cell-to-cell recognition processes. In this study, our aims were to determine the distribution of sperm receptors with activity for fucosyl- and galactosyl glycans and to address whether monosugar neoglycoproteins functionally mimic the binding between zona pellucida (ZP) glycoproteins and spermatozoa. In mouse epididymal spermatozoa with intact acrosomes, fucopyranosyl bovine serum albumin (BSA-Fuc) bound to the segment of the acrosome, the equatorial segment, and the postacrosome region of the sperm head. Galactosyl BSA (BSA-Gal) binding activity was similar to that of BSA-Fuc, but was weaker. In acrosome-reacted spermatozoa treated with the Ca(2+) ionophore A23187, BSA-zuc binding was lost in the apical segment of the acrosome but remained in the equatorial segment and postacrosome regions. BSA-Gal binding to the equatorial region was increased. In the presence of 2.5 µg ml(-1) BSA-Fuc, in vitro sperm-ZP binding was significantly decreased, indicating that fucosyl BSA functionally mimics ZP glycoproteins during sperm-egg ZP interactions. At the same concentration, BSA-Gal was not effective. Fucosyl BSA that efficiently inhibited the sperm-ZP binding can mimic the ZP glycoconjugate and has potential for use as a sperm fertility control agent in mouse.


Subject(s)
Egg Proteins/metabolism , Membrane Glycoproteins/metabolism , Receptors, Cell Surface/metabolism , Spermatozoa/metabolism , Zona Pellucida/metabolism , Animals , Calcimycin/pharmacology , Female , Fucose/metabolism , Galactose/metabolism , Glycoproteins/metabolism , Male , Mice , Serum Albumin, Bovine/metabolism , Sperm-Ovum Interactions , Spermatozoa/drug effects , Zona Pellucida Glycoproteins
18.
Phys Rev Lett ; 110(15): 157202, 2013 Apr 12.
Article in English | MEDLINE | ID: mdl-25167303

ABSTRACT

Although abundant research has focused recently on the quantum criticality of itinerant magnets, critical phenomena of insulating magnets in the vicinity of critical endpoints (CEP's) have rarely been revealed. Here we observe an emergent CEP at 2.05 T and 2.2 K with a suppressed thermal conductivity and concomitant strong critical fluctuations evident via a divergent magnetic susceptibility (e.g., χ''(2.05 T,2.2 K)/χ''(3 T,2.2 K)≈23,500%, comparable to the critical opalescence in water) in the hexagonal insulating antiferromagnet HoMnO3.

19.
Phys Rev Lett ; 108(11): 116402, 2012 Mar 16.
Article in English | MEDLINE | ID: mdl-22540494

ABSTRACT

Using transmission electron microscopy, the anomalies in resistivity and magnetic susceptibility at ~262 K in IrTe2 are found to accompany the superlattice peaks with q[over q=(1/5,0,-1/5). The wave vector is consistent with our theoretical calculation for the Fermi surface nesting vector, indicating that the ~262 K transition is of the charge-orbital density wave (DW) type. We also discovered that both Pd intercalation and substitution induce bulk superconductivity with T(c) up to ~3 K, which competes with DW in a quantum critical pointlike manner.

20.
Andrologia ; 44 Suppl 1: 187-93, 2012 May.
Article in English | MEDLINE | ID: mdl-21592178

ABSTRACT

Parabens have been shown to affect male rodent reproductive parameters, including testosterone levels and sperm production. In this study, we examined the effect of long-term exposure to butyl paraben (BP) on rat epididymal sperm DNA methylation. Adult male rats were exposed to BP (0, 10, 100 and 1000 mg kg(-1) per day) according to OECD TG407 for a repeated 28-day oral toxicity study. Sperm DNA methylation was examined by differential display random amplification of polymorphic DNA (RAPD) following methylation-specific restriction digestion of DNA. Among the 57 RAPD amplicons, six were methylation specific. Of these, five amplicons increased by 1.4- to 3.8-fold in epididymal sperm DNA at testing dose of BP. This indicates that BP can cause DNA hypermethylation in germ cells from the mitotic through post-meiotic stage in adult rat testes. To our knowledge, this is the first report on the epigenetic modification of sperm DNA by parabens.


Subject(s)
DNA Methylation/drug effects , Epididymis/drug effects , Parabens/pharmacology , Spermatozoa/drug effects , Animals , Dose-Response Relationship, Drug , Epididymis/cytology , Male , Random Amplified Polymorphic DNA Technique , Rats
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