Iris cyst after femtosecond laser-assisted cataract surgery: a case report.

BACKGROUND: Secondary iris cysts are uncommon complication after cataract surgery. The reports of an iris cyst after conventional phacoemulsification surgery are scanty, let alone the iris cyst following femtosecond laser-assisted cataract surgery (FLACS). We herein report an unusual case of an iris cyst after an uneventful FLACS. CASE PRESENTATION: A 64-year-old man who was healthy underwent FLACS for a moderate cataract of his left eye. Shortly after surgery, he achieved 20/20 vision, but anterior bowing of temporal iris was noted on postoperative day 9 with a retro-pupillary iris cyst at temporal-inferior quadrant found after pupil dilatation. The cyst was confirmed by ultrasound bio-microscopy afterward. Four weeks later, argon laser cystotomy was performed, and the cyst disappeared 3 days later. The patient's vision remained stable thereafter. CONCLUSION: Although rare, secondary iris cyst may be one of the complications after FLACS. Argon laser cystotomy is effective in the management of post-FLACS iris cyst.

Aryl hydrocarbon receptor promotes hepatocellular carcinoma tumorigenesis by targeting intestine-specific homeobox expression.

The aryl hydrocarbon receptor (AHR), a major chemical sensor, is thought to play a role in various biological contexts, including cell cycle regulation and tumorigenesis. However, its regulatory mechanisms remain unclear. We propose herein a novel mechanism through which AHR promotes tumorigenesis by targeting expression of the oncogene intestine-specific homeobox (ISX) in hepatocellular carcinoma (HCC). Compared to paired tumor-adjacent tissues and non-HCC tumors, HCCs exhibited an increased and hierarchical pattern of AHR expression. Patients exhibiting high AHR expression had a significantly shorter survival duration, compared to those with low and medium expression. Functionally, AHR was found to target the newly discovered proto-oncogene, ISX, resulting in the increased expression of this gene and its downstream targets, CCND1 and E2F1. Ablation of AHR or ISX in hepatoma cells suppressed cell growth, whereas overexpression promoted cell proliferation and led to enhanced tumorigenic activity in vitro and in vivo. These results provide evidence to support a critical role for the AHR/ISX axis in HCC tumorigenesis and suggest its potential utility as a new therapeutic and prognostic target for HCC.

Possible association between phantom vibration syndrome and occupational burnout.

BACKGROUND: Phantom vibration syndrome (PVS) and phantom ringing syndrome (PRS) occur in many cell phone users. Previous studies have indicated an association between PVS/PRS and job stress. The aim of this study was to determine if PVS/PRS were also associated with occupational burnout. METHODS: This was a cross-sectional study of 384 employees of a high-tech company in northern Taiwan. They all completed a phantom vibration and ringing questionnaire, the Hospital Anxiety and Depression Scale, and the Chinese version of the Occupational Burnout Inventory. RESULTS: Significantly more women and people with at least a college education were in the population with PRS and PVS, respectively. Anxiety and depression had no associations with PVS/PRS. Higher scores for personal fatigue, job fatigue, and service target fatigue had an independent impact on the presence of PVS, but only a higher score for service target fatigue had an independent impact on the presence of PRS. CONCLUSION: The independent association between work-related burnout and PVS/PRS suggests that PVS/PRS may be a harbinger of mental stress or a component of the clinical burnout syndrome, and may even be a more convenient and accurate predictor of occupational burnout.

Synthesis and unexpected oxidization of the tricyclic core of ugibohlin, isophakellin, and styloguanidine.

A series of 4-substituted 5,6,7,9-tetrahydropyrrolo[2,3-f]indolizin-9-ones, representing the tricyclic core skeleton of ugibohlin, isophakellin, and styloguanidine, were synthesized via an intramolecular Vilsmeier-Haack reaction. This reaction allows the chemoselective C-C bond formation between the pyrrole C3 and proline C5 of N-[(pyrrol-2-yl)carbonyl]prolinamides to construct the B-ring without the protection of the pyrrole nitrogen. Unexpected oxidizative property of the tricyclic core skeleton was observed, which could illuminate understanding of the biological formation of these marine secondary metabolites.

Early-onset behavioral and synaptic deficits in a mouse model of Alzheimer's disease.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder for which numerous mouse models have been generated. In both AD patients and mouse models, there is increasing evidence that neuronal dysfunction occurs before the accumulation of beta-amyloid (Abeta)-containing plaques and neurodegeneration. Characterization of the timing and nature of preplaque dysfunction is important for understanding the progression of this disease and to identify pathways and molecular targets for therapeutic intervention. Hence, we have examined the progression of dysfunction at the morphological, functional, and behavioral levels in the Tg2576 mouse model of AD. Our data show that decreased dendritic spine density, impaired long-term potentiation (LTP), and behavioral deficits occurred months before plaque deposition, which was first detectable at 18 months of age. We detected a decrease in spine density in the outer molecular layer of the dentate gyrus (DG) beginning as early as 4 months of age. Furthermore, by 5 months, there was a decline in LTP in the DG after perforant path stimulation and impairment in contextual fear conditioning. Moreover, an increase in the Abeta42/Abeta40 ratio was first observed at these early ages. However, total amyloid levels did not significantly increase until approximately 18 months of age, at which time significant increases in reactive astrocytes and microglia could be observed. Overall, these data show that the perforant path input from the entorhinal cortex to the DG is compromised both structurally and functionally, and this pathology is manifested in memory defects long before significant plaque deposition.

Mouse models of human neurodegenerative disorders: requirements for medication development.

Central nervous system diseases constitute a major target for drug development. Transgenic mouse models, in which genes identified in familial forms of human brain diseases are expressed in mouse neurons and glia, offer opportunities to detect and follow pathologic progression and provide potential biomarkers by which to assess therapeutic interventions. Evidence for Alzheimer disease suggests some starting requirements for the experimental data that could enhance the likelihood of developing medications in these mouse models that would also be effective in humans.

Selective vulnerability of dentate granule cells prior to amyloid deposition in PDAPP mice: digital morphometric analyses.

Increasing evidence from mouse models of Alzheimer's disease shows that overexpression of a mutant form of the amyloid precursor protein (APP) and its product, beta-amyloid peptide, initiate pathological changes before amyloid deposition. To evaluate the cytological basis for one of these early changes, namely reduced volume of the dentate gyrus (DG), we have used high-throughput diOlistic cell loading and 3D neuronal reconstruction to investigate potential dendritic pathology of granule cells (GCs) in 90-day-old PDAPP mice. Labeled GCs from fixed hippocampal slices were selected randomly and imaged digitally by using confocal laser-scanning microscopy. The dendritic complexity of GCs was quantified according to subordinate morphological parameters, including soma position within the granule cell layer (superficial versus deep) and topographic location within the DG (dorsal versus ventral blade) along the anterior-posterior hippocampal axis. Initial analysis, which included all sampled GC types, revealed a 12% reduction of total dendritic length in PDAPP mice compared with littermate controls. Further analysis, performed with refined subgroups, found that superficially located GCs in the dorsal blade were profoundly altered, exhibiting a 23% loss in total dendritic length, whereas neurons in the ventral blade were unaffected. Superficial GCs were particularly vulnerable (a 32% reduction) in the posterior region of the DG. Furthermore, the dendritic reductions of this select group were uniformly localized within middle-to-outer portions of the dentate molecular layer. We conclude that substantial dendritic pathology is evident in 90-day-old PDAPP mice for a spatially defined subset of GCs well before amyloid accumulation occurs.

High-throughput morphometric analysis of individual neurons.

To facilitate high-throughput quantitative analysis of neuronal structure, this study optimized the diOlistic method of whole neuron labeling to examine multiple neurons in fixed brain, and optimized image acquisition parameters to preserve signal for subsequent photoconversion. Fluorescent dye-coated gold particles were successively delivered by helium-powered ejection to 250 microm thick brain slices with loading density and penetration depth optimized to maximize the yield of labeled neurons within the slice while avoiding overlapping labeled dendritic processes in the x-y plane and z-axis. Labeled neurons were imaged using confocal laser-scanning microscopy with pinhole aperture and scan speed enhanced to minimize capture time and fluorescence degradation. Optimized image acquisition parameters preserved fluorescence signal and facilitated subsequent oxygen-enriched photoconversion for higher magnification dendritic spine analysis. Sampling criteria limited analysis to neurons whose z-axis dendritic processes were fully contained within the tissue slice and in which dye transport extended to the most distal portions of the dendrites. The yield of completely labeled neurons was, on average, more than 20 cells per brain region per animal. With optimized spatio-temporal diOlistic loading parameters, along with image acquisition parameters optimized for subsequent photoconversion, the present protocol provides a high-throughput strategy for full-scale quantitative analysis of three-dimensional neuronal morphology.

Electron Transfer in Mixed-Valence [Fe(III)(2)Fe(II)O(O(2)CCH(3))(6)(3-Cl-py)(3)].3-Cl-py: Effects of a Crystallographic Phase Transition and Conversion of Solvate and Ligand Molecules from Statically Disordered to Dynamically Disordered on the Valence Detrapping.

A crystallographic phase transition involving changes in the solvate molecule has been found for mixed-valence [Fe(3)O(O(2)CCH(3))(6)(3-Cl-py)(3)].3-Cl-py (1), where 3-Cl-py is 3-chloropyridine. Single-crystal X-ray structures were determined at 300, 228, 200, 169, and 122 K for complex 1. At 300, 228, and 200 K the crystal is monoclinic, space group P2(1)/c, whereas at 169 and 122 K it is triclinic, space group P&onemacr;. Determinations of the unit cell parameters at several temperatures shows that a reversible crystallographic phase transition between the monoclinic and triclinic forms occurs at approximately 200 K. Complex 1 crystallizes in the monoclinic space group P2(1)/c at 300 K, having a unit cell with a = 21.212(8) Å, b = 8.434(2) Å, c = 23.676(3) Å, and Z = 4. Refinement with 5702 observed [F(o) > 4sigma(F(o))] reflections gave R = 0.0542 and R(w) = 0.0937. Complex 1 crystallizes in the triclinic space group P&onemacr; at 122 K, having a unit cell with a = 20.983(11) Å, b = 8.360(4) Å, c = 23.293(10) Å, and Z = 4. At 300 K there is one somewhat asymmetric Fe(3)O complex in the structure. The core dimensions in the Fe(3)O complex at 300 K indicate that the complex is becoming almost valence-detrapped. At 122 K there are two different Fe(3)O complexes in the unit cell, both of which are similar in dimensions. As the temperature is decreased from 300 to 122 K, each Fe(3)O complex becomes more and more distorted in an equilateral triangle. At 122 K one iron ion in each Fe(3)O complex clearly is a high-spin Fe(II) ion and the other two are high-spin Fe(III) ions. There are significant changes in the nature of the 3-Cl-py solvate molecules above and below the phase transition that are likely important in controlling the valence detrapping. At 122 K there are two different Fe(3)O complexes, each with their nearby 3-Cl-py solvate molecules in one position. There are three different phases: a monoclinic one with all solvate molecules disordered, a second triclinic phase at 169 K with half of the solvate molecules disordered, and a third triclinic phase at 122 K with all solvate molecules statically ordered. (57)Fe Mössbauer spectra taken in the 110-293 K range show that complex 1 converts from valence-trapped at 110 K to become detrapped by 293 K, where a single quadrupole-split doublet is seen. Throughout the 140-230 K range it was necessary to employ one Fe(III) doublet and two Fe(II) doublets to fit each Mössbauer spectrum. It is shown that the two Fe(II) doublets likely arise from Fe(3)O complexes experiencing the different disordered solvate environments described above. Thus, while the approximately 200 K structural phase transition involving the solvate molecules does not precipitously lead to an increase in the rate of electron transfer in Fe(3)O complexes in 1, it is clear that the changes seen in the solvate molecules from X-ray structures do play a major role in the valence detrapping in complex 1.

Solvate Molecule Effects and Unusual (57)Fe Mössbauer Line Broadening in the Valence Detrapping of Mixed-Valence [Fe(3)O(O(2)CCH(3))(6)(3-Et-py)(3)].S.

A new series of mixed-valence &mgr;(3)-oxo-bridged Fe(3)O complexes with the composition [Fe(3)O(O(2)CCH(3))(6)(3-Et-py)(3)].S, where 3-Et-py is 3-ethylpyridine and the solvate molecule S is either 0.5C(6)H(5)CH(3) (1), 0.5C(6)H(6) (2), CH(3)CN (3), or CH(3)CCl(3) (4), is reported. The complex [Fe(3)O(O(2)CCH(3))(6)(3-Et-py)(3)].0.5C(6)H(5)CH(3) (1) crystallizes in the orthorhombic space group Fdd2 which at 298 K has a unit cell with a = 22.726(8) Å, b = 35.643(14) Å, c = 20.816(6) Å, and Z = 16. Refinement with 5720 observed [F > 5sigma(F(o))] reflections gave R = 0.0337 and R(w) = 0.0390. An analysis of the bond lengths in complex 1 shows that it is the most valence-trapped Fe(3)O complex reported at room temperature. The complex [Fe(3)O(O(2)CCH(3))(6)(3-Et-py)(3)].CH(3)CCl(3) (4) crystallizes in the triclinic space group P&onemacr; which at 238 K has a unit cell with a = 12.764(2) Å, b = 13.1472(2) Å, c = 15.896(3) Å, alpha = 78.01(2) degrees, beta = 89.38(2) degrees, gamma = 61.38(1) degrees, and Z = 2. Refinement with 6264 observed [F > 5sigma(F(o))] reflections gave R = 0.0435 and R(w) = 0.0583. In this &mgr;(3)-oxo-bridged complex all three iron ions are inequivalent. Powder X-ray diffraction patterns taken at room temperature show that complexes 1 and 2 are isostructural and that complexes 3 and 4 are isostructural. Variable-temperature (57)Fe Mössbauer spectra were collected for all four complexes. The data for complexes 1 and 2 clearly indicate that these two complexes are totally valence trapped. On the other hand, Mössbauer spectra (43-293 K) for complexes 3 and 4 show that these two complexes become valence detrapped at temperatures near room temperature. Two doublets are seen at low temperature and they move together to become a single doublet at approximately 293 K. Examination of the line width versus temperature for each of the two components of the two doublets points to a curiosity. The two components of the "Fe(III)" doublet and the lower-velocity component of the "Fe(II)" doublet do not exhibit any line broadening, whereas the higher velocity "Fe(II)" component shows a surge in line width in the approximately 70-150 K range. Possible explanations for these unusual line width responses are discussed.