Modified Orbitozygomatic Approach for Resecting a Parasellar Tumor in a Single Institution.

BACKGROUND: Modified orbitozygomatic craniotomy is characterized by simplicity and wide exposure. The purpose of the present study was to describe a modified orbitozygomatic approach without resecting the zygomatic arch for large parasellar tumor surgeries. METHODS: Between April 2016 and December 2019, seven patients with parasellar tumor underwent surgiest with a modified orbitozygomatic approach. Surgical procedures, clinical outcomes, and complications were analyzed. RESULTS: This study included 3 meningiomas, 2 pituitary adenomas, 1 chondrosarcoma, and 1 schwannoma. Modified orbitozygomatic craniotomy provides a wider surgical freedom in the opticocarotid and prechiasmatic cistern than frontotemporal craniotomy without orbitotomy, Total, subtotal, and partial resections were achieved for 3, 2, and 2 patients, respectively. Reasons for partial resections were tight adhesion to the carotid artery and encasing of the carotid artery. Permanent morbidities developed in one patient with 3rd nerve palsy and one patient with hemiparesis. CONCLUSION: Modified orbitozygomatic approach can provide the shortest access to the interpeduncular cistern with a minimum brain retraction. Surgeons who experience surgical challenge during the conventional approach for parasellar tumor resection are recommended to learn the modified orbitozygomatic approach.

Procyanidins from Vitis vinifera seeds induce apoptotic and autophagic cell death via generation of reactive oxygen species in squamous cell carcinoma cells.

Procyanidins can inhibit cell proliferation and tumorigenesis and induce apoptosis in human skin, breast and prostate carcinoma cell lines. Squamous cell carcinoma (SCC) of the skin is a common form of keratinocytic or non-melanoma skin cancer and is a deadly disease with a poor prognosis due to the ineffectiveness of therapy. The present study aimed to determine whether grape seed proanthocyanidin (GSP) may regulate different modes of cell death in the human SCC12 cell line. The present study found that the treatment of SCC12 cells with GSP inhibited proliferation in a dose-dependent manner and reduced the motility and invasiveness of SCC12 cells through suppression of matrix metalloproteinase-2/9 expression. GSP treatment also resulted in induction of apoptosis and autophagy via generation of reactive oxygen species. The inhibition of autophagy by 3-methyladenine decreased GSP-induced cell death, which suggested that GSP-induced autophagy can promote cell death. The results of the present study suggested that autophagy functions as a death mechanism in SCC and provided a rationale for the use of GSP in combination with autophagy activators for treating cancers such as SCC.

Preparation of "Constrained Geometry" Titanium Complexes of [1,2]Azasilinane Framework for Ethylene/1-Octene Copolymerization.

The Me2Si-bridged ansa-Cp/amido half-metallocene, [Me2Si(η5-Me4C5)(NtBu)]TiCl2, termed a "constrained-geometry catalyst (CGC)", is a representative homogeneous Ziegler catalyst. CGC derivatives with the [1,2]azasilinane framework, in which the amide alkyl substituent is joined by the Si-bridge, were prepared, and the catalytic performances of these species was studied. Me4C5HSi(Me)(CH2CH=CH2)-NH(C(R)(R')CH=CH2) (R, R' = H or methyl; Me4C5H = tetramethylcyclopentadienyl) was susceptible to ring closure metathesis (RCM) when treated with Schrock's Mo-catalyst to afford -Si(Me4C5H)(Me)CH2CH=CHC(R)(R')NH- containing a six-membered ring framework. Using the precursors and the products of RCM, various CGC derivatives, i.e., [-Si(η5-Me4C5)(Me)CH2CH=CHC(R)(H)N-]TiMe2 (13, R = H; 15, R = Me), [-Si(η5-Me4C5)(Me)CH2CH2CH2CH2N]TiMe2 (14), [(η5-Me4C5)Si(Me)(CH2CH=CH2)NCH2CH=CH2]TiMe2 (16), [(η5-Me4C5)Si (Me)(CH=CH2)NCH2CH=CH2]TiMe2 (17), and [(η5-Me4C5)Si(Me)(CH2CH3)NCH2CH2CH3]TiMe2 (18), were prepared. The catalytic activity of the newly prepared complexes was lower than that of CGC when activated with [Ph3C][B(C6F5)4]/iBu3Al. However, the catalytic activity of these species was improved by using tetrabutylaluminoxane ([iBu2Al]2O) instead of iBu3Al and the activity of 14/[Ph3C][B(C6F5)4]/[iBu2Al]2O was comparable to that of CGC/[Ph3C][B(C6F5)4]/iBu3Al (4.7 and 5.0 × 106 g/mol-Ti, respectively). Advantageously, the newly prepared complexes produced higher molecular weight poly(ethylene-co-1-octene)s than CGC.

Mechanical properties of decellularized tendon cultured by cyclic straining bioreactor.

Decellularized tissues have been successfully used in tissue engineering and regenerative medicine for the purpose of removing antigens present in the cellular components. However, this decellularization technique uses ionic solutions or chemical treatments such as enzyme treatments that might damage the biophysical properties or reduce the physical strength of tissue. This study aimed to improve the strength of decellularized tissues. We designed a tissue bioreactor that can repeatedly deliver physical stimulation, such as tensile and torsional deformation, to the upper and lower parts of a tissue. To decellularized porcine Tibialis tendons, we used an enzymatic solution to remove the primary cells, and then applied ultrasonic cleansing using a combination of ionic solution and distilled water to destroy residual cells by differing from the osmotic pressure between the inside and outside of the cell membrane. The total DNA content of decellularized tissue was decreased by 77% compared with that of the original tissue and the ultimate tensile strength of the decellularized tissue was 20% lower than that of the normal tissue. Decellularized tissues were then cultivated in the tissue bioreactor with repeated physical stimulation of 110% tension, 90° torsion, and frequency of once per a second, and the ultimate tensile strength was found to be greater than that of the normal ligament at 7 day culture. This study showed that decellularization using enzyme and mechanical treatment is safe and use of a tissue bioreactor can increase the physical strength of tendons, making this a potential mechanism to reconstruct human ligaments.

Brain activation patterns of motor imagery reflect plastic changes associated with intensive shooting training.

Evidence from previous studies has suggested that motor imagery and motor action engage overlapping brain systems. As a result of this observation that motor imagery can activate brain regions associated with actual motor movement, motor imagery is expected to enhance motor skill performance and become an underlying principle for physical training in sports and physical rehabilitation. However, few studies have examined the effects of physical training on motor imagery in beginners. Also, differences in neural networks related to motor imagery before and after training have seldom been studied. In the current study, using functional magnetic resonance imaging (fMRI), we investigated the question of whether motor imagery can reflect plastic changes of neural correlates associated with intensive training. In fact, motor imagery was used in this study as a tool to assess the brain areas involved in shooting and involved in learning of shooting. We discovered that use of motor imagery resulted in recruitment of widely distributed common cortical areas, which were suggested to play a role in generation and maintenance of mental images before and after 90 h of shooting training. In addition to these common areas, brain activation before and after 90 h of shooting practice showed regionally distinct patterns of activity change in subcortical motor areas. That is, basal ganglia showed increased activity after 90 h of shooting practice, suggesting the occurrence of plastic change in association with gains in performance and reinforcement learning. Therefore, our results suggest that, in order to reach a level of expertise, the brain would change through initial reinforcement of preexistent connections during the training period and then use more focused neural correlates through formation of new connections.

Induction of melanogenesis by rapamycin in human MNT-1 melanoma cells.

BACKGROUND: Melanogenesis is one of the characteristic parameters of differentiation in melanocytes and melanoma cells. Specific inhibitors of phosphatidylinositol 3-kinase (PI3K), such as wortmannin and LY294002, stimulate melanin production in mouse and in human melanoma cells, suggesting that PI3K and mammalian target of rapamycin (mTOR) might be involved in the regulation of melanogenesis. OBJECTIVE: The involvement of the mTOR pathway in regulating melanogenesis was examined using human MNT-1 melanoma cells, and the effects of the potent inhibitor of mTOR, rapamycin, in the presence or absence of α-melanocyte-stimulating hormone (α-MSH) were evaluated. METHODS: In cells treated with rapamycin, cell viability, melanin content, and tyrosinase (TYR) activity were measured and compared with untreated controls. Protein levels of TYR, tyrosinase-related protein (TYRP)-1, TYRP-2, and microphthalmia-associated transcription factor (MITF) were also analyzed by Western blot. RESULTS: In rapamycin-treated cells, the melanin content increased concomitantly with an elevation in TYR activity, which plays a major role in melanogenesis. There was also an up-regulation of TYR, TYRP-1, and MITF proteins. Combined treatment with rapamycin or wortmannin and α-MSH increased melanogenesis more strongly than α-MSH alone. CONCLUSION: Rapamycin-induced melanin formation may be mediated through the up-regulation of TYR protein and activity. Furthermore, rapamycin and wortmannin, inhibitors of mTOR and PI3K, respectively, have co-stimulatory effects with α-MSH in enhancing melanogenesis in melanocyte cells.

Stronger activation and deactivation in archery experts for differential cognitive strategy in visuospatial working memory processing.

It is well known that elite athletes have higher performance in perception, planning, and execution in sports activities relative to novices. It remains controversial, however, whether any differences in basic cognitive functions between experts and novices exist. Furthermore, few studies have directly used functional magnetic resonance imaging (fMRI) to investigate neural activation and deactivation differences between experts and novices while performing visuospatial working memory (WM) tasks. Therefore, the purpose of this study was to examine possible differences in neural activation and deactivation associated with working memory components in processing visuospatial information between archery experts and novices. To this end, we employed a judgment of line orientation (JLO) task, which has a strong WM component. With regard to brain activation, archery experts displayed higher activation in cortical areas associated with visuospatial attention and working memory, including the middle frontal cortex, supplemental motor area, and dorsolateral prefrontal cortex than that of the novices during the performance of the JLO task. With regard to brain deactivation, archery experts exhibited stronger task-related deactivation in cortical areas, such as the paracentral cortex/precuneus and the anterior and posterior cingulate cortex related to the default network, than that of the novices. These results suggest that the archery experts have a strategy that demands greater use of neural correlates associated with visuospatial working memory and attention in addition to greater use of DMN in visuospatial working memory task not directly tied to their domain of expertise.

Fluconazole induced fixed drug eruption.

We report on a rare case of fluconazole induced fixed drug eruption in a 62-year old female patient. She was referred to our department for multiple erythematous itchy maculopatches on the face, neck, both upper arms, and trunk area, which had occurred over the previous 6 months. Her attending physician prescribed fluconazole for treatment of onychomycosis. Patch test and oral provocation were performed. The patch test showed a negative result; however, the result for oral provocation was positive, confirming this as a rare case of fluconazole induced fixed drug eruption. To the best of our knowledge, this is the first reported case in Korean dermatologic literature.

Neural correlates of motor imagery for elite archers.

Motor imagery is a mental rehearsal of simple or complex motor acts without overt body movement. It has been proposed that the association between performance and the mental rehearsal period that precedes the voluntary movement is an important point of difference between highly trained athletes and beginners. We compared the activation maps of elite archers and nonarchers during mental rehearsal of archery to test whether the neural correlates of elite archers were more focused and efficiently organised than those of nonarchers. Brain activation was measured using functional MRI in 18 right-handed elite archers and 18 right-handed nonarchers. During the active functional MRI imagery task, the participants were instructed to mentally rehearse their archery shooting from a first-person perspective. The active imagery condition was tested against the nonmotor imagery task as a control condition. The results showed that the premotor and supplementary motor areas, and the inferior frontal region, basal ganglia and cerebellum, were active in nonarchers, whereas elite archers showed activation primarily in the supplementary motor areas. In particular, our result of higher cerebellar activity in nonarchers indicates the increased participation of the cerebellum in nonarchers when learning an unfamiliar archery task. Therefore, the difference in cerebellar activation between archers and nonarchers provides evidence of the expertise effect in the mental rehearsal of archery. In conclusion, the relative economy in the cortical processes of elite archers could contribute to greater consistency in performing the specific challenge in which they are highly practised.

MKK6 increases the melanocyte dendricity through the regulation of Rho family GTPases.

BACKGROUND: Melanocyte dendrites serve as the principal conduit for melanosome transfer. The dendrite formation requires actin polymerization mediated by Rho family GTPases including RhoA, Rac1 and Cdc42. OBJECTIVE: The aim of this study is to investigate and explore the involvement of p38 MAPK in melanocyte dendrite formation. METHODS: We transduced melanoma cells with adenovirus harboring the expression cassette for constitutive active form of MKK6, an upstream MAPKK for p38 MAPK. RESULTS: We investigated the effect of melanogenic inducers on melanocyte dendricity, using SK-mel-24 melanoma cells because that this cell line is refractory to several melanogenic inducers in terms of melanogenesis. TPA-induced the phosphorylation of p38 MAPK and the elongation of dendrite length, suggesting that MKK6 may be involved in this process. Overexpression of the constitutive active form of MKK6 resulted in significant elongation of dendrites in the melanoma cell line SK-mel-24. Moreover, overexpression of MKK6 ultimately led to the upregulation of Cdc42 and Rac1, suggesting that MKK6 acts as a crucial upstream signaling molecule for Rho family GTPases. When overexpressed in normal human epidermal melanocytes, MKK6 led also the increase of dendrite length. CONCLUSION: These results suggest that MKK6 is an authentic regulator for melanocytes dendricity, through the modulation of Rho family GTPases.

Treatment of oral lichen sclerosus with 1% pimecrolimus cream.

Lichen sclerosus is a chronic inflammatory mucocutaneous disorder predominately affecting prepubertal girls and postmenopausal women. Isolated lichen sclerosus affecting the oral mucosa is exceedingly rare, and only 13 patients with biopsy-proved isolated oral disease have been reported in the literature. We report on a 7-year-old Korean girl with a well-demarcated 1.2x1.2 cm atrophic white plaque with an erythematous border and focal telangiectasia on the left vermillion lip, extending to the labial mucosa. No other cutaneous surfaces, including genitalia, were involved. An incisional biopsy of the plaque on the lip revealed a patchy lichenoid infiltrate of lymphocytes associated with sclerosis of the papillary dermis and a thinned epidermis consistent with a diagnosis of linear orofacial lichen sclerosus. Treatment with a short course of 1% pimecrolimus cream effectively prevented the progression of this lesion.

A case of atypical granuloma annulare involving both ears.

We report a rare case of granuloma annulare (GA), affecting both ear antihelixes, in a 28-year old male patient that presented with a 1-year history of non-tender, firm, skin-colored, 1~5 mm papules on both ear antihelixes. There was no history of trauma. An excisional biopsy specimen taken from one of the lesions of the right ear revealed infiltration of histiocytes and lymphocytes around a zone of collagen alteration in the dermis. Based on the clinical and pathological findings, the patient was diagnosed with a rare case of bilateral GA of both antihelixes; this is the first report in the Korean dermatology literature.

Sensitive and simple method for the determination of nicotine and cotinine in human urine, plasma and saliva by gas chromatography-mass spectrometry.

A method is proposed for the determination of nicotine and cotinine in human urine, plasma and saliva. Nicotine and cotinine were extracted from alkalinized sample with ethyl ether and concentrated to minimum volume with nitrogen stream. The volatility of nicotine was prevented by the addition of acetic acid to the organic solvent during evaporation. Peak shapes and quantitation of nicotine and cotinine are excellent, with linear calibration curves over a wide range of 1-10,000 ng/ml. The detection limits of nicotine and cotinine are 0.2 ng/ml in urine and 1.0 ng/ml in plasma and saliva. The intra-day precision of nicotine and cotinine in all samples was <5% relative standard deviation (RSD). Urine, plasma and saliva samples of 303 non-smoking and 41 smoking volunteers from a girl's high school in Korea were quantified by the described procedure. As a result, the concentrations of nicotine and cotinine in plasma ranged from 6 to 498 ng/ml and 4 to 96 ng/ml. Otherwise, those of nicotine and cotinine in saliva ranged from 0 to 207 ng/ml and 0 to 42 ng/ml, and those of nicotine and cotinine in urine ranged from 0 to 1,590 ng/ml and 0 to 2,986 ng/ml, respectively. We found that the concentration of cotinine in plasma was successfully predicted from the salivary cotinine concentration by the equation y=2.31x+4.76 (x=the concentration of cotinine in saliva, y=the concentration of cotinine in plasma). The results show that through the accurate determination of cotinine in saliva, the risk of ETS-exposed human can be predicted.

Reaction equilibrium of penicillin G with amberlite LA-2 in a nonpolar organic solvent.

Studies have been made of the reactive extraction of penicillin G by Amberlite LA-2, a secondary amine, dissolved in kerosene. On the basis of the previous works about extraction equilibria of monocarboxylic acids by some secondary amines in low polar organic solvents, four equilibrium models were suggested to describe the reaction equilibrium of penicillin G in the liquid-liquid extraction system. The calculated results from the models were compared with the experimental data of 96 runs, and only two equilibrium models seemed to be probable. Ultimately, the most reasonable extraction equilibrium model was chosen through spectroscopic studies on organic solutions obtained by five specific extraction equilibrium experiments.