Response to sunitinib in Chinese KIT-mutated metastatic mucosal melanoma

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Background: To investigate the possible relationship between sunitinib response and KIT mutation as well as KIT expression. Methods: We find that a 75-year male patient with KIT-mutated metastatic mucosal (primary: nasal, metastasis: left adrenal gland, lungs and right eye) melanoma has a very good response to sunitinib 37.5mg/d consecutively. We apply IHC sp assay to detect S100, HMB-45, CD117, VEGFR, PDGFR and EGFR in the melanoma sample of this patient. DNA is also extracted from paraffin-embedded melanoma sample of this patient and PCR is carried out to amplify several exons of C-KIT (exon11,13,17,18),B-RAF(exon11, 15) and N- RAS(exon1, 2). PCR products are sent to be directly sequenced. Clinical response, PFS and OS of the patient are evaluated. Results: Strong expression of S100, HMB45, CD117, VEFGR and PDGFR is detected by IHC in the tissue sample of the patient. Furthermore, direct sequencing after PCR reveals that V559A substitution is detected in exon 11 of KIT, with mutation of T into C at 1776, leading to substitution of Valine by Alanine at 559. No mutation was detected in exon 9, 13, 17, 18 of KIT, B-RAF15, 11 or N-RAS1, 2. The patient received sunitinib 37.5mg/d from July 2008 consecutively and evaluated PR (Recist: tumors shrink 70%) lasting for 5 months with Grade II myelosuppression and stomatitis. Now the patient is still alive and received sunitinib. Conclusions: Our case report suggests that response of melanoma patients to sunitinib might be correlated to KIT mutation and expression, and large-scale clinical trial in patients with KIT mutation and over-expression might be useful to shed light on treatment of melanoma patients with individual targeted therapy.

No significant financial relationships to disclose.

Endostatin combined with chemotherapy as first-line therapy for stage IV melanoma patients: A phase II clinical study

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Background: To observe the efficacy and safety of rh-endostatin injection (Endostar) combined with chemotherapy as first line therapy for stage IV melanoma patients. Methods: From March 2007-March 2008, 20 metastatic melanoma patients were enrolled. Endostar (15 mg d1–14) combined with dacarbazine (250 mg/m2 d1–5) or temozolomide (300 mg d 1–5) and fotemustine (100 mg/m2 d6) were given every 28days. Response, toxicity and progression free survival(PFS) were analyzed. Results: Among 20 evaluable cases, with mean cycle 2.7±0.80, four achieved partial response, six stable disease, with response rate 20.0% (4/20) and clinical benefit rate 50.0% (10/20). The median PFS reached 4.5 months (95% CI: 3.85–6.9 months), overall survival 8.5 months (95% CI: 5.62–8.54 months), with 6 months PFS rate 35% (7/20), and 6 months survival rate 65% (13/20). The Grade 3/4 toxicity was mainly myelosuppression, 40% (8/20). One patient ceased the treatment because of sinus bradycardia. Conclusions: Endostar combined with chemotherapy show its efficacy on melanoma patients and may prolong PFS.

No significant financial relationships to disclose.

Durable response of the triple combination of temozolomide, sorafenib, and bevacizumab as second-line therapy for patients with stage IV acral melanoma

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Background: Temozolomide (TMZ) is an oral formulation of dacarbazine with improved central nervous system penetration. Sorafenib inhibits Raf kinase and vascular endothelial growth factor (VEGF) receptor. Bevacizumab is a monoclonal antibody targeted against VEGF. TMZ plus sorafenib has shown efficacy in advanced melanoma. The triple combination, chemotherapy plus the complementary inhibition of VEGF signaling, was hypothesized to have synergistic effects on acral metastatic melanoma. Methods: Eligible are refractory (previous one systemic regimen failed) acral advanced melanoma, measurable disease (RECIST). Treatment includes TMZ 200 mg/m2/d (days 1–5), bevacizumab 5 mg/Kg (days 1, 14) and sorafenib 400 mg/bid (days 1–28), repeated every 28days. VEGFR, PDGFR, EGFR and CD117 of tumor tissue were detected by Immunohistochemistry (IHC) assay and the DNA was abstracted and amplified by PCR assay and then sequenced to detect the mutation of C-KIT (exon11,13,17,18),B- RAF(exon11, 15) and N-RAS(exon1, 2). Progression free survival (PFS), overall survival (OS), response and toxicity were assessed. Correlation was analyzed between gene mutations, IHC results and clinical response. Results: 50 patients were planned to recruit. Till December of 2008, 11 patients all in M1c stage have been enrolled and evaluated. One patient has achieved complete response (CR) which has been lasting 5 cycles. One patient has achieved partial response (PR) with a 69% tumor reduction which has been lasting 3 cycles. One patient achieved PR with a 41% tumor reduction which has been lasting 6 cycles. 6 pts got stable disease (all tumor reduction, range: 4–21%) lasting > 2 cycles (range: 3–4 cycles); and 2 PD after 1 cycle. The toxicity was moderate. It's too early to assess survival. It seemed no correlation between positive IHC results and response. It could not be decided if there is correlation between gene mutation/IHC results and response/survival. Conclusions: The triple combination (TMZ, sorafenib, and bevacizumab) regimen preliminary achieved durable clinical response especially the patients with CR or PR. The regimen is safe and well tolerated. More data will be presented in ASCO.

No significant financial relationships to disclose.

Intra-arterial hepatic bio-chemotherapy for the treatment of melanoma patients with liver metastasis: A phase II clinical study

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Background: To investigate the efficacy and safety of hepatic intra-arterial infusion of cisplatin, fotemustine combined with systemic dacarbazine for the treatment of melanoma patients with liver metastasis. Methods: From 2005.7 to 2008.7, thirty-six melanoma patients with liver metastatic were enrolled. Systemic dacarbazine (250mg/m2 d1–5) and intra-arterial hepatic (i.a.h.) of cisplatin (75mg/m2 d6) and fotemustine (100mg/m2 d7) were given repeated for 4-weeks. Response, progress free survival(PFS), and toxicity were analyzed. Results: 27 of the 36 patients were evaluable, with mean cycle 2.16±1.19, one achieved CR, one PR and seven SD. The disease control rate was 33.3% (9/27) with a median PFS of 3.5 months (95% CI 3.45–7.02months), overall survival of 7.5 months (95 CI 6.87–11.06 months, following to 2008.8). The Grade 3/4 toxicity was mainly myelosuppression, with occurrence rates of 40.7% (10/27). Conclusions: Intra-arterial hepatic chemotherapy show its efficacy and may prolong PFS in melanoma patients with liver metastasis.

No significant financial relationships to disclose.

Siderophore production by the marine-derived Aureobasidium pullulans and its antimicrobial activity

Over 300 yeast strains isolated from different marine environments were screened for their ability to produce siderophore. Among them, only the yeast strain HN6.2 which was identified to be Aureobasidium pullulans was found to produce high level of the siderophore. Under the optimal conditions, this yeast strain could produce 1.1mg/ml of the siderophore. The crude siderophore produced by the yeast strain HN6.2 was able to inhibit cell growth of Vibrio anguillarum and Vibrio parahaemolyticus, isolated from the diseased marine animals.

Purification and characterization of killer toxin from a marine yeast Pichia anomala YF07b against the pathogenic yeast in crab

The molecular mass of the purified killer toxin from the marine killer yeast YF07b was estimated to be 47.0 kDa. The optimal pH and temperature of the purified killer toxin were 4.5 and 40 degrees C, respectively. The toxin was activated by Ca(2+), K(+), Na(+), Mg(2+), Na(+), and Co(2+). However, Fe(2+), Fe(3+), Hg(2+), Cu(2+), Mn(2+), Zn(2+), and Ag(+) acted as inhibitors in decreasing activity of the toxin. The toxin was strongly inhibited by phenylmethanesulphonyl fluoride (PMSF), iodoacetic acid, ethylenediaminetetraacetic acid, and 1,10-phenanthroline. The Km of the toxin for laminarin was 1.17 g L(-1). The toxin also actively hydrolyzed laminarin and killed the whole cells of the pathogenic yeast in crab.

A new exopolysaccharide produced by marine Cyanothece sp. 113

Cyanothece sp. 113, a unicellular, aerobic, diazotrophic and photosynthetic marine cyanobacterium, produced 22.34 g/l of exopolysaccharide in 11 days at 29 degrees C, aeration rate of 7.0 l/min and continuous illumination with 4300 lux. After purification, the spectra of UV, IR, (1)H NMR, (13)C NMR and GC-MS analysis showed that the purified exopolysaccharide was alpha-D-1,6-homoglucan. This is first report describing linear alpha-D-1,6-homoglucan exopolysaccharide produced by marine cyanobacteria.

Optimization of medium and cultivation conditions for alkaline protease production by the marine yeast Aureobasidium pullulans

A yeast strain, Aureobasidium pullulans, which could produce the high yield of protease was isolated from sediment of saltern in Qingdao, China. Maximum production of enzyme (623.1 U/mg protein; 7.2 U/ml) was obtained in a medium containing 2.5 g soluble starch and 2.0 g NaNO(3), 100ml seawater, initial pH 6.0, after fermentation at 24.5 degrees C for 30 h. The protease had the highest activity at pH 9.0 and 45 degrees C.

Temporal precision and temporal drift in brain and behavior of zebra finch song

In the zebra finch forebrain nucleus robustus archistriatalis (RA), neurons burst during singing. We showed that the internal structure of spike bursts was regulated with a precision of circa 0.2 ms, and yielded alignment of acoustic features of song with a precision of circa 1 ms. In addition, interburst intervals and corresponding syllable durations displayed systematic variation within song (average elongation 0.3 ms/s song), and slower "drift" across songs. Systematic variation on even a coarser time scale might be difficult to detect in other systems, but could affect the analysis of temporal patterning. The close relationship between precise timing of individual spikes and stereotypic behavior suggests that song is represented in RA by a temporal code.

Laser-induced fluorescence studies of polycyclic aromatic hydrocarbons (PAH) vapors at high temperatures

In this work, we present the fluorescence spectra of anthracene and pyrene vapors at different elevated temperatures (from 150 to 650 degrees C) excited with the 337 nm line of a nitrogen laser. We describe the high temperature effects on the resulting spectral properties including spectral intensity, spectral bandwidth and spectral shift. We found that the PAH fluorescence spectral bandwidths become very broad as the temperature increases. The broadening is mainly due to thermal vibrational sequence congestion. We also have found that the fluorescence intensity of pyrene vapor increases with increasing temperature, which results from the increase of the pyrene vapor absorption cross section at 337 nm.

Trehalose accumulation from soluble starch by Saccharomycopsis fibuligera sdu

Trehalose accumulation from starch by Saccharomycopsis fibuligera sdu was examined in 300-ml shaken flask culture and Biostat B(2) 2-1 fermentation. In the 300-ml flask, 16.5% (w/w) trehalose accumulated in the yeast cells (cell dry weight) was observed with 100-ml medium shaken at 200 rpm for 50 h at 30 degrees C. We found that 1.0% soluble starch in the medium was most suitable for trehalose accumulation by this yeast strain. In the Biostat B(2) 2-1 fermentor, 18.0% (w/w) trehalose accumulated in the yeast cells (cell dry weight) was observed within 48 h of fermentation when agitation speed was 200 rpm. The trehalose obtained from the yeast cells was identical to standard trehalose from Sigma based on the analysis results of High-Performance Exchange Anionic Chromatography (HPEAC).

A semi-parametric hybrid neural model for nonlinear blind signal separation

Nonlinear blind signal separation is an important but rather difficult problem. Any general nonlinear independent component analysis algorithm for such a problem should specify which solution it tries to find. Several recent neural networks for separating the post nonlinear blind mixtures are limited to the diagonal nonlinearity, where there is no cross-channel nonlinearity. In this paper, a new semi-parametric hybrid neural network is proposed to separate the post nonlinearly mixed blind signals where cross-channel disturbance is included. This hybrid network consists of two cascading modules, which are a neural nonlinear module for approximating the post nonlinearity and a linear module for separating the predicted linear blind mixtures. The nonlinear module is a semi-parametric expansion made up of two sub-networks, one of which is a linear model and the other of which is a three-layer perceptron. These two sub-networks together produce a "weak" nonlinear operator and can approach relatively strong nonlinearity by tuning parameters. A batch learning algorithm based on the entropy maximization and the gradient descent method is deduced. This model is successfully applied to a blind signal separation problem with two sources. Our simulation results indicate that this hybrid model can effectively approach the cross-channel post nonlinearity and achieve a good visual quality as well as a high signal-to-noise ratio in some cases.

Ultraviolet resonance Raman examination of horse apomyoglobin acid unfolding intermediates

We have used UV resonance Raman spectroscopy to study the acid-induced denaturation of horse apomyoglobin (apoMb) between pH 7. 0 and 1.8. The 206.5 nm excited Raman spectra are dominated by amide vibrations, which are used to quantitatively determine the apoMb secondary structure. The 229 nm excited Raman spectra are dominated by the Tyr and Trp Raman bands, which are analyzed to examine changes of Tyr and Trp environments and solvent exposures. We observe two partially unfolded apoMb intermediates at pH 4 and pH 2, while we observe only one partially unfolded holoMb intermediate at 2, in which the G and H helices are mainly intact, while the rest of protein is unfolded. This partially unfolded holoMb intermediate at pH 2 is essentially identical to the pH 2 apoMb intermediate. The partially unfolded pH 4 apoMb intermediate is composed of the three folded A, G, and H helices and contains 38% helical structure. The changes in the Trp Raman cross sections during the acid-induced denaturation indicates that Trp 7 is likely to be fully exposed in the apoMb pH 4 intermediate and that the A helix melts with a pKa approximately 3.5.

Relationship between lipid composition, frequency of ethanol-induced respiratory deficient mutants, and ethanol tolerance in Saccharomyces cerevisiae

The frequency of ethanol-induced respiratory deficient mutants and lipid composition in two Saccharomyces cerevisiae strains showing different degrees of ethanol tolerance were investigated. The more ethanol-tolerant strain exhibited a lower frequency of ethanol-induced respiratory deficient mutants than the less ethanol-tolerant strain. In addition, the more ethanol-tolerant strain contained a higher ergosterol/phospholipid ratio, a higher proportion of phosphatidylcholine, a lower proportion of phosphatidylethanolamine, a higher incorporation of long-chain fatty acids in total phospholipids, and a slightly higher proportion of unsaturated fatty acids in total phospholipids than the less ethanol-tolerant strain. These results show a clear relationship between the lipid composition, the frequency of ethanol-induced respiratory deficient mutants, and the ethanol tolerance of S. cerevisiae. A possible explanation of this relationship is discussed.

Ultraviolet Raman examination of the environmental dependence of bombolitin I and bombolitin III secondary structure

Bombolitin I and III (BI and BIII) are small amphiphilic peptides isolated from bumblebee venom. Although they exist in predominately nonhelical conformations in dilute aqueous solutions, we demonstrate, using UV Raman spectroscopy, that they become predominately alpha-helical in solution at pH > 10, in high ionic strength solutions, and in the presence of trifluoroethanol (TFE) and dodecylphosphocholine (DPC) micelles. In this paper, we examine the effects of electrostatic and hydrophobic interactions that control folding of BI and BIII by systematically monitoring their secondary structures as a function of solution conditions. We determine the BI and BIII secondary structure contents by using the quantitative UV Raman methodology of Chi et al. (1998. Biochemistry. 37:2854-2864). Our findings suggest that the alpha-helix turn in BIII at neutral pH is stabilized by a salt bridge between residues Asp2 and Lys5. This initial alpha-helical turn results in different BI and BIII alpha-helical folding mechanisms observed in high pH and high salt concentrations: BIII folds from its single alpha-helix turn close to its N-terminal, whereas the BI alpha-helix probably nucleates within the C-terminal half. We also used quasielastic light scattering to demonstrate that the BI and BIII alpha-helix formation in 0.2 M Ca(ClO4)2 is accompanied by formation of trimers and hexamers, respectively.

Expression of beta1,4-galactosyltransferase in the development of mouse brain

Beta1,4-galactosyltransferase (GalTase, EC 2.4.1.38) transfers galactose to the terminal N-acetylglucosamine of complex-type N-glycans, which have great importance for cell-cell interactions during fertilization and early embryogenesis. In this study, the activity of beta1,4-galactosyltransferase in mouse brain during development was measured with the method of reverse HPLC using a fluorescence-labeled biantenary sugar chain, GlcNAcbeta1-2Manalpha1-6(GlcNAcbeta1-2Manalpha1- 3) Manbeta1-4GlcNAcbeta1-4GlcNAc-PA. The level of messenger RNA of this enzyme during the development of mouse brain was also investigated with Northern blot analysis. The results showed that: (1)beta1,4-galactosyltransferase showed similar branch specificity and kinetics for the biantenary substrate during development; (2) GalTase activity in fetal mouse brain was four times higher than that in adult mouse brain and decreased gradually in the course of development; (3) messenger RNA level was highest in fetal mouse and decreased dramatically after birth. However, the contents of mRNA were not parallel to the enzyme activity.

Neural network approach for Compton-scattering imaging

The problem of image reconstruction with Compton-scattering spectral data is an ill-posed problem, and the measurement error may be seriously amplified in the reconstruction result. For a stable solution, some kinds of a priori models of the problem should be incorporated into the process of reconstruction. Lee et al. [IEEE. Trans. Nucl. Sci. 40, 2049 (1993)] have proposed a continuous model with binary line processes. Owing to the coexistence of the continuous variable and the binary variable, the commonly used optimization methods for problems with continuous variables cannot be used in this case, and therefore a coupled-gradient artificial neutral network was proposed for this mixed-integer problem. By introducing two interacting parts (with one part for the continuous variable and the other for the binary line processes) into the network, and by defining the appropriate energy function and dynamics, high-quality solutions were obtained upon convergence of the dynamics. Some simulated results are presented.

The C-truncated delta-opioid receptor underwent agonist-dependent activation and desensitization

The agonist-dependent activation and desensitization of a recombinant analog of delta-opioid receptor lacking the carboxyl-terminal (C-terminal) 31 residue peptide segment were discussed. The cDNA of the C-truncated delta-opioid receptor was created by polymerase chain reaction (PCR), stably expressed in Chinese hamster ovary cells and characterized by binding assay and function assay. Agonist [D-Pen2, D-Pen5]-enkephalin (DPDPE) stimulated the specific [35S]GTPgammaS binding to membrane fragments of cells expressing the C-truncated and the wild-type delta-opioid receptors in different levels dose-dependently. EC50 values of DPDPE on truncated and wild-types in stimulation were very similar. Agonist-dependent desensitization, which could be blocked by protein kinase inhibitor staurosporine (Stau), was observed after pretreating truncated receptors with 1 microM DPDPE for 10 min, the same as wild-types. The results reveal that the C-terminal of the delta-opioid receptor is not involved in controlling the G-protein activation and phosphorylation-related functional desensitization.

UV resonance Raman-selective amide vibrational enhancement: quantitative methodology for determining protein secondary structure

We have directly determined the amide band resonance Raman spectra of the "average" pure alpha-helix, beta-sheet, and unordered secondary structures by exciting within the amide pi-->pi* transitions at 206.5 nm. The Raman spectra are dominated by the amide bands of the peptide backbone. We have empirically determined the average pure alpha-helix, beta-sheet, and unordered resonance Raman spectra from the amide resonance Raman spectra of 13 proteins with well-known X-ray crystal structures. We demonstrate that we can simultaneously utilize the amide I, II, and III bands and the Calpha-H amide bending vibrations of these average secondary structure spectra to directly determine protein secondary structure. The UV Raman method appears to be complementary, and in some cases superior, to the existing methods, such as CD, VCD, and absorption spectroscopy. In addition, the spectra are immune to the light-scattering artifacts that plague CD, VCD, and IR absorption measurements. Thus, it will be possible to examine proteins in micelles and other scattering media.

UV resonance Raman determination of protein acid denaturation: selective unfolding of helical segments of horse myoglobin

We have used UV resonance Raman spectroscopy to study the acid denaturation of horse heart aquometmyoglobin (Mb) between pH 7.5 and 1.5. Raman spectra excited at 206.5 nm are dominated by amide vibrations, which are analyzed by using a new methodology to quantitatively determine the Mb secondary structure. In contrast, the 229-nm Raman spectra are dominated by the Tyr and Trp Raman bands, which are analyzed to examine changes in Tyr and Trp environments, such as exposure to water, hydrogen bonding, and, for Trp, any alterations of the dihedral angle between the Trp ring and its linkage to the protein backbone. We uniquely determined which Mb alpha-helices melt by combining the amide, Tyr, and Trp Raman spectral information with heme absorption spectral information. We calculate that the Mb alpha-helical composition decreases from approximately 80% at neutral pH to approximately 19% below pH 3.5. The Trp Raman cross sections dramatically decrease at low pH to values which indicate that they are fully exposed to water; this result indicates that the A helix melts. The Tyr Raman bands are pH independent, which indicates that the G and H helices around the Tyr residues do not melt. The dramatic heme absorption acid denaturation changes indicate major alterations of the heme pocket and changes in heme binding. These results indicate that the A, B, C, D, E, and F helices melt in a concerted fashion, while the antiparallel G and H helices only partially melt.

[Clinical significance of measuring serum c-peptide before and after glucagon injection]

To evaluate pancreatic beta-cell secretory activity, c-peptide concentrations before and 6 minutes after an i.v. injection of glucagon were measured in 12 normal subjects (group N), 23 diabetics treated with diet control and oral antidiabetics (group DI) and 71 patients treated with insulin (group DII). The results showed that the fasting c-peptide concentration in group N and group DI were comparable, but significantly higher than that in group DII. An overlap was found between fasting c-peptide from 6 diabetics in group DI and that from group DII. There were significant differences among the c-peptide concentrations 6 minutes after glucagon injection in the three groups and there was no overlap between c-peptide in group DI and that in group DII 6 minutes after injection. The above-mentioned data suggest that c-peptide concentration 6 minutes after glucagon injection may reflect beta-cell secretory activity better than fasting c-peptide.

HLA-A, B and HLA-DR phenotypes in Mainland Chinese patients with diabetes mellitus

HLA-A, B and DR antigens were studied in Mainland Chinese diabetes mellitus patients and controls (31 Type I DM, 50 Type II DM, 105 controls). HLA-DR3 and HLA-A9 were increased in Type I diabetics only. An increase in HLA-DR4 was noted in Type I diabetics, but the increase was not statistically significant in this small series.