Aldosterone-producing adrenocortical carcinoma without hypertension

Although adrenocortical tumors are common, adrenocortical carcinomas are rare. Moreover, aldosterone-producing adrenocortical carcinomas without hypertension are exceedingly rare, with only two previously reported cases.     

The diagnostic utility of cerebrospinal fluid alpha-synuclein analysis in dementia with Lewy bodies – A systematic review and meta-analysis

BackgroundDementia with Lewy Bodies (DLB) can be difficult to distinguish clinically from other dementias.ObjectiveTo investigate the diagnostic utility of CSF alpha-synuclein in differentiating between DLB and other dementias.MethodsElectronic databases were systematically searched for studies investigating reproducible alpha synuclein quantification methods. Random effects model was used to calculate weighted mean difference (WMD) and 95% confidence intervals between DLB and other groups.ResultsA total of 13 studies, comprising 2728 patients were included. Mean CSF alpha-synuclein concentration was significantly lower in DLB patients compared to those with Alzheimers disease (AD) [WMD ?0.24; 95% CI, ?0.45, ?0.03; p = 0.02]. No significant difference was found between patients with DLB compared to Parkinsons disease [WMD 0.05; 95% CI, ?0.17, 0.28; p = 0.65] or other neurodegenerative conditions.ConclusionCSF alpha synuclein may be of diagnostic use in differentiating between DLB and AD. We propose several recommendations to guide better design of future studies.     

Postmorbid learning of saxophone playing in a patient with frontotemporal dementia

Some patients with frontotemporal dementia (FTD) show an artistic enhancement of musical abilities. However, no patients with FTD, to date, have been reported to be able to learn how to play a musical instrument after disease onset. Herein we describe a patient (J. K.) who had never played any musical instruments premorbidly, but who learned to play the saxophone after being diagnosed with a behavioral variant of FTD. He mastered a repertoire that consisted of 10 pieces of Korean folk songs over a period of three years. Furthermore, his saxophone skills were high enough to outperform other students in his class.     

Tegillarca granosa extract Haishengsu (HSS) suppresses expression of mdr1, BCR/ABL and sorcin in drug-resistant K562/ADM tumors in mice

PurposeTo evaluate the effect of Haishengsu (HSS), a protein extract from Tegillarca granosa, on multidrug-resistance genes mdr1, BCR/ABL and sorcin in transplanted tumors.Material/MethodsMice were inoculated subcutaneously with a drug resistant leukemia cell line K562/ADM. Tumor-bearing animals were divided into control, adriamycin, HSS and combination therapy (adriamycin plus HSS) groups. Flow cytometry was used to detect apoptosis of tumor cells, and RT-PCR was used to evaluate the expression of mdr1, BCR/ABL and sorcin.ResultsThe apoptosis rate in the high (71.8%), medium (72.3%) and low doses HSS group (72.4%) was higher than in control (1.2%, p<0.01), adriamycin (34.4%, p<0.05) or combination therapy group (46.4%, p<0.05). The mean optical density of mdr1, BCR/ABL and sorcin in HSS groups was lower than in control, adriamycin and combination therapy group (p<0.01). The optical density of the three genes in high HSS group was lower than in medium and low HSS group (p<0.01).ConclusionsHaishengsu promotes apoptosis of drug-resistant K562/ADM tumors in mice in a dose-dependent manner. The pro-apoptotic effect of Haishengsu may be related to a reduced expression of multidrug-resistance genes mdr1, BCR/ABL and sorcin.     

Mass spectrometric analysis of acid-assisted photochemical release of the trimethyl lock system on the monolayers on gold

We report the acid-assisted photolysis of the trimethyl lock system which has long been harnessed for a variety of applications such as drug delivery, cellular imaging, enzyme activity assays, and surface patterning. By mass spectrometric analysis, we found that photoinduced intramolecular cyclization and the ensuing release of the pendant groups of the trimethyl lock on the self-assembled monolayers proceeded cleanly in the presence of HCl, to give a high yield.

The acid-assisted photolysis of the trimethyl lock on the surface was characterized by mass spectrometry.

The release of a specific substance under certain conditions is advantageous for modulating the activities and properties of biological/chemical molecules.^1,2 In this regard, the trimethyl lock, o-hydroxydihydrocinnamic acid with three methyl substituents, has long been harnessed for drug delivery, cellular imaging, enzyme activity assays, ligand/surface patterning, and development of gradient surfaces.^3–6 The trimethyl lock is initiated by demasking phenolic oxygen, which then undergoes intramolecular cyclization (lactonization), resulting in the release of pendant groups. A number of methods have been used for trimethyl lock initiation, including chemical/electrochemical reduction, photochemical induction, and enzyme reactions.^2,7–10 Photochemical reduction appears to be advantageous over other initiation methods, as it does not require any complicated reagents or instruments and allows spatiotemporal control of on-demand activation.Recently, the Dougherty''s group reported photodecaging trimethyl lock systems based on a quinone redox reaction in which a photoinduction leads to the cleavage of amine/alcohol groups.^11,12 Inspired by this photocleavable molecule, we have designed a photoresponsive dynamic surface for the photochemical release of the pendant groups of trimethyl locks, which has not yet been reported, to the best of our knowledge. The complete cleavage of target bonds without any significant side reactions upon activation is of utmost importance in surface releasing systems. Thus, photoinduced cleavage of the trimethyl lock on surfaces must be investigated prior to the use of this lock in various applications. In this study, we report on the preparation of the surface releasing system using quinone-based photocleavable trimethyl lock (Q-PTL) derivatives with ester or amide functionality and molecular-level characterization of photochemical reactions. Our system relies on self-assembled monolayers (SAMs) on gold and matrix-assisted laser desorption ionization time-of flight mass spectrometry (MALDI-TOF MS), known as SAMDI, for characterization.^13–15 This is a powerful and efficient tool for analysis of the SAMs on gold because of its short timeframes, simple sampling process, and high degree of discrimination of multiple analytes despite structural similarities. This paper will also discuss the findings of our study. A key finding is that the photochemical release of Q-PTL on the surface is strongly enhanced under acidic conditions, particularly in the Q-PTL-amide (Fig. 1).Open in a separate windowFig. 1Schematic of the acid-assisted photochemical release of the trimethyl lock on the surface. Scheme 1 illustrates the synthesis of Q-PTL derivatives used in this study. Briefly, carboxylic acid containing trimethyl lock quinone with protected thiol (6) was prepared by a conjugation reaction between a thiol molecule (4) and brominated trimethyl-lock quinone (5). Subsequent tethering to an alcohol (1-hexanol) or an amine (benzyl amine) followed by deprotecting the thiol group afforded Q-PTL-ester (7) or Q-PTL-amide (10). For the preparation of 2 and 5, see Fig. S1.^† Note that 5 was synthesized using a method previously reported by the Dougherty''s group.¹¹Open in a separate windowScheme 1Synthesis of Q-PTL derivatives.First, we analyzed the photochemical reaction of Q-PTL derivatives in solution for a better understanding of the photolysis characteristics of Q-PTL. It was known that a quinone with a sulfide as an electron door, such as Q-PTL, shows broad absorbance near 400 nm, and the photolysis and release of caged molecules in methanol proceed cleanly including a solvent capture step through zwitterion intermediates without a complex mixture of byproducts.¹² Thus, we irradiated the Q-PTL solution in MeOH or EtOH by 395 nm light for photoinduction. The Q-PTL-ester or amide solution in MeOH or EtOH (1 mM) was irradiated at 395 nm for 5 min, incubated for an additional 5 min, and analyzed by MALDI-TOF MS. The observed mass peaks for the photochemical reaction were in very good accordance with the previous report by the Dougherty''s group,¹² and we elucidated the photochemical products on the basis of mass data. As seen in mass spectra, the peak corresponding to the Q-PTL-ester (△) decreased significantly after irradiation, and gave rise to the peaks due to the solvent captured lactonized products (□ in MeOH and ◇ in EtOH) (Fig. 2(a)). Unlike Q-PTL-ester, Q-PTL-amide (▲) gave rise to solvent captured, non-lactonized quinone products (■ in MeOH and ◆ in EtOH) with relatively high intensity compared to that for solvent captured lactonized products (□ and ◇) (Fig. 2(b)). This difference may be attributed to the bond strength difference between the amide and the ester. The amide nitrogen forms a conjugate system by delocalization of the lone pair electrons into the carbonyl group, resulting in a partial double bond character between nitrogen and carbon, and thus, a stronger bond than the ester bond. Therefore, the hydroquinone intermediate produced by photoreduction and subsequent solvent capture may have sufficient time to be oxidized to the corresponding quinone rather than to lactonize, as shown in Fig. 1. For this reason, we harnessed acid-catalyzed amide bond cleavage to promote the lactonization. Fig. 2(c) clearly shows that when Q-PTL-amide was irradiated in the presence of HCl, the solvent captured quinone products (■ and ◆) completely disappeared and the solvent captured lactonized products (□ and ◇) were formed with high peak intensity. Note that the treatment of Q-PTL-amide with HCl for 10 min in the absence of irradiation did not affect the stability of Q-PTL-amide (Fig. 2(c), first panel).Open in a separate windowFig. 2Mass spectrometric analysis and peak assignments for photochemical reactions of (a) Q-PTL-ester, (b) Q-PTL-amide, and (c) Q-PTL-amide in the presence of HCl (* matrix peak).Second, we applied acid-assisted photolysis of Q-PTL to the photo-triggered release system on surfaces. Accordingly, we utilized SAMs on a gold platform, where chemical/biochemical conversion could be easily analyzed by MALDI-TOF MS. Fig. 3(a) illustrates the preparation of Q-PTL-presenting SAMs and the acid-assisted photochemical release process. Carboxylic acid groups amongst a tri(ethyleneglycol) background on gold were coupled with N-(2-aminoethyl)maleimide, and subsequent thiol-Michael addition of Q-PTL derivatives to maleimide led to Q-PTL-presenting SAMs. We then verified the acid-assisted photochemical release of Q-PTL on the surface by mass spectrometry. In general, disulfides of alkanethiolates were the dominant species observed in MALDI-TOF MS profile of the SAMs on gold. The Q-PTL-ester presenting monolayer gave rise to peaks for Q-PTL-ester-containing disulfide (◎) (Fig. 3(b), first panel). Following irradiation, the mass spectrometric analysis revealed peaks due to photochemical lactonized products (lactone disulfide ☆ and solvent captured lactone disulfide ★) with traces of the starting material (◎) (Fig. 3(b), second panel). When an identical monolayer was irradiated in the presence of HCl (5 mM), only lactone disulfide (☆) was observed, indicating reaction completion (Fig. 3(b), third panel). The same experiment was performed for the Q-PTL-amide presenting monolayer (Fig. 3(c)). Following irradiation, high-density peaks for Q-PTL-amide-containing disulfide (▽) still appeared, whereas peaks for photochemical lactonized products (☆ and ★) had low density. In addition, considerable amount of the solvent captured non-lactonized quinone disulfide (▼) was observed, unlike the case for the Q-PTL-ester surface. When the monolayer was irradiated in the presence of HCl (5 mM), only lactone disulfide (☆) was observed, similar to the case of the Q-PTL-ester monolayer, clearly implying that the lactonization and ensuing release of alcohol or amine pendant are facilitated by HCl. These results are significant because surface releasing systems require the complete cleavage of target bonds without any significant side reactions upon activation as we discussed above. For the optimization of acid-assisted photochemical release on the surface, the Q-PTL-presenting monolayers were treated with 1 mM HCl, resulting in a higher yield of photochemical lactonized products (☆ and ★) compared to that for the untreated surfaces (Fig. S2^†). Interestingly, unlike in solution, the solvent capture process was not dominant on the surface, and even was not observed with HCl treatment. Furthermore, upon irradiation without HCl treatment, a trace amount of non-lactonized solvent captured quinone disulfide was observed for the Q-PTL-ester, whereas the Q-PTL-amide surface yielded high-density peaks for solvent captured non-lactonized quinone disulfide (▼). Although we cannot confirm this observation at present, we presume that the solvent molecules have reduced accessibility to the photoinduced zwitterion intermediates on the surface than in solution, leading to lactonization without solvent capture.Open in a separate windowFig. 3(a) Schematic illustration for preparing Q-PTL-presenting monolayers and subsequent photochemical release. Mass spectrometric analysis and peak assignments for the acid-assisted photochemical release of (b) the Q-PTL-ester presenting monolayers and (c) the Q-PTL-amide presenting monolayers.Finally, we verified the fidelity of our acid-assisted photochemical cleavage of the trimethyl lock for practical surface release systems via selective photoactivation. The prepared maleimide-presenting monolayers were immersed into a solution of Q-PTL-NHS which was prepared from 6 and N-hydroxysuccinimide, and subsequently treated with amine-modified red fluorescent microspheres (Fig. 4(a)). Half of the resulting Q-PTL-microsphere-presenting monolayers were irradiated at 395 nm in the presence of HCl (5 mM) in MeOH. Fluorescence microscopy analysis using a Texas Red filter showed that the fluorescence from the unmasked region of the monolayer had disappeared almost completely, whereas the masked region of the monolayer was intact. This indicated the selective release of fluorescent microspheres in the photoinduced region of the Q-PTL monolayers (Fig. 4(b)).Open in a separate windowFig. 4(a) Schematic of the immobilization of amine-modified fluorescent microspheres on SAMs. (b) Fluorescence imaging after photochemical release of the fluorescent microspheres by partial irradiation through masks.A variety of strategies for photochemical removal of protecting groups and surface releasing systems with photochemical initiation have been reported. For example, Wang et al. introduced photochemical cleavage of benzylic C–N and C–O bonds for the release of amines, alcohols, and carboxylic acids.^16–18 Kikuchi et al. demonstrated a dynamic surface for light-induced cell migrations, and Miguel et al. realized caged surfaces for wavelength-selective release of chromophores by harnessing photo-labile linkers.^19,20 In most cases, the photoinduction was performed by irradiating 250–350 nm UV light which sometimes can be invasive to biological and biochemical systems, while photoinductions at longer wavelengths are not common. On the other hand, the trimethyl lock system described here can operate into the visible range by synthetic modifications.¹¹ In addition, our surface releasing system relies on SAMs on gold, which provide various advantages over other types of scaffolds. For example, SAMs on gold are stable in contact with air and water and suitable for biological applications. In addition, they can be characterized with MALDI-TOF MS, and therefore, chemical or biochemical conversions on the surface along with structural changes can be easily trackable.In summary, we synthesized quinone-based photocleavable trimethyl lock (Q-PTL) derivatives with ester of amide functionality. MALDI-TOF MS analysis revealed that Q-PTL-amide showed inefficient photochemical cleavage of the tethered molecular moiety upon irradiation, unlike the case of the Q-PTL-ester. However, the degree of photolysis significantly improved under acidic conditions. We also confirmed that the photochemical release of Q-PTL on the surface was greatly enhanced under acidic conditions. The feasibility of the Q-PTL releasing system from the surface was verified by fluorescence imaging. We believe that our strategy will be helpful for various applications utilizing photoinduced trimethyl locks.     

BRAF V600E Mutation Analysis in Papillary Thyroid Carcinomas by Peptide Nucleic Acid Clamp Real-time PCR

Background

Activating somatic mutation of the BRAF ^V600E has been identified as the most common genetic event in papillary thyroid carcinoma (PTC) with a variable frequency (32–87 %) in different series by different methods. The BRAF ^V600E mutation is associated with various clinicopathological parameters. The mutation is an important factor for the management of the PTC patients. The objective of this study was to detect the BRAF ^V600E mutation in PTCs by peptide nucleic acid (PNA) clamp real-time PCR and to analyze the results with clinicopathological parameters.

Methods

We performed genetic analysis of BRAF ^V600E by PNA clamp real-time PCR in 211 PTCs in Korea, stratified by clinicopathological parameters.

Results

The BRAF ^V600E mutation was detected in 90 % of PTC cases, and it occurred significantly more often in female patients than in male patients (p = 0.001). The clinicopathological parameters of age, tumor size, and disease stage were not associated with the BRAF ^V600E mutation, while extrathyroid invasion (p = 0.031), lymph nodal metastasis (p = 0.002), and tumor multiplicity (p = 0.020) were.

Conclusions

The prevalence (90 %) of the BRAF ^V600E mutation in this study is the highest ever reported, confirming the key role of this mutation in PTC tumorigenesis. The BRAF ^V600E mutation was associated with aggressive clinical behaviors including extrathyroid invasion, lymph nodal metastasis and tumor multifocality. The PNA clamp real-time PCR method for the BRAF ^V600E mutation detection is sensitive and is applicable in a clinical setting.