Real-time multichannel imaging framework for endoscopy, catheters, and fixed geometry intraoperative systems

To address the need for a clinically applicable intravital optical imaging system, we developed a new hardware and software framework. We demonstrate its utility by applying it to an endoscope-based white light and fluorescent imaging system. The capabilities include acquisition and visualization algorithms that perform registration, segmentation, and histogram-based autoexposure of two imaging channels (full-spectrum white light and near-infrared fluorescence), all in real time. Data are processed and saved as 12-bit files, matching the standards of clinical imaging. Dynamic range is further improved by the evaluation of flux as a quantitative parameter. The above features are demonstrated in a series of in vitro experiments, and the in vivo application is shown with the visualization of fluorescent-labeled vasculature of a mouse peritoneum. The approach may be applied to diverse systems, including handheld devices, fixed geometry intraoperative devices, catheter-based imaging, and multimodal systems.     

An HSV vector system for selection of ligand-gated ion channel modulators

Pathological alterations of ion channel activity result from changes in modulatory mechanisms governing receptor biology. Here we describe a conditional herpes simplex virus (HSV) replication-based strategy to discover channel modulators whereby inhibition of agonist-induced channel activation by a vector-expressed modulatory gene product prevents ion flux, osmotic shock and cell death. Inhibition of channel activity, in this case, the rat vanilloid (Trpv1 or the glycine receptor (GlyRalpha1), can allow selection of escape vector plaques containing the 'captured' modulatory gene for subsequent identification and functional analysis. We validated this prediction using mixed infections of a wild-type Trpv1 expression vector vTTHR and a nonfunctional 'poreless' Trpv1 subunit-expressing vector, vHP, wherein vHP was highly selected from a large background of vTTHR viruses in the presence of the Trpv1 agonist, capsaicin. The approach should be useful for probing large libraries of vector-expressed cDNAs for the presence of ion channel modulators.     

The gene encoding the splicing factor SF2/ASF is a proto-oncogene

Alternative splicing modulates the expression of many oncogene and tumor-suppressor isoforms. We have tested whether some alternative splicing factors are involved in cancer. We found that the splicing factor SF2/ASF is upregulated in various human tumors, in part due to amplification of its gene, SFRS1. Moreover, slight overexpression of SF2/ASF is sufficient to transform immortal rodent fibroblasts, which form sarcomas in nude mice. We further show that SF2/ASF controls alternative splicing of the tumor suppressor BIN1 and the kinases MNK2 and S6K1. The resulting BIN1 isoforms lack tumor-suppressor activity; an isoform of MNK2 promotes MAP kinase-independent eIF4E phosphorylation; and an unusual oncogenic isoform of S6K1 recapitulates the transforming activity of SF2/ASF. Knockdown of either SF2/ASF or isoform-2 of S6K1 is sufficient to reverse transformation caused by the overexpression of SF2/ASF in vitro and in vivo. Thus, SF2/ASF can act as an oncoprotein and is a potential target for cancer therapy.     

Movement and bioaccumulation of chromium in an artificial freshwater ecosystem

In the present study, a small fresh water aquatic ecosystem was created into a small test tank to evaluate the movement and bioaccumulation of Cr (VI) through water, sediment, a macrophyte Hydrilla, small fish guppy, and few key organs of magur, Clarias batrachus. The Cr (VI) intoxication was imposed of as a single dose of 30 mg/l concentration for a wide range of exposure durations like 1, 7, 14 and 21 days. After 1 day of exposure the total Cr (VI) load was very high in the water and sediment samples (5.187 microg/ml and 23.332 microg/g respectively) which were decreased with increasing exposure durations over their respective controls. In samples of macrophyte, Cr (VI) concentration showed a gradual increasing trend from 6.1797 microg/g in control to 21.1903 microg/g in 1 day exposure and reached up to 24.635 microg/g after 21 days exposure. In guppy, the Cr (VI) bioaccumulation showed an increasing trend but the rate was not statistically significant. However, in magur, the Cr (VI) uptake showed a significant gradual and increasing trend with increasing exposure durations in liver, brain, intestine and muscular tissues than gill and kidney over their respective controls. The movement of the Cr (VI) was found to be from sediment to water during pre-treatment phase, after intoxication, from water to macrophyte and to other phytoplankton and zooplankton. It then accumulated in the primary consumer guppy and finally moved to the secondary consumer the magur following the food web. The results reveal that the rate of movement and bioaccumulation of Cr (VI) varied from organism to organism and in C. batrachus, from tissue to tissue.     

A model for agonism and antagonism in an ancient and ubiquitous cAMP-binding domain

The cAMP-binding domain (CBD) is an ancient and conserved regulatory motif that allosterically modulates the function of a group of diverse proteins, thereby translating the cAMP signal into a controlled biological response. The main receptor for cAMP in mammals is the ubiquitous regulatory (R) subunit of protein kinase A. Despite the recognized significant potential for pharmacological applications of CBDs, currently only one group of competitive inhibitor antagonists is known: the (R(p))-cAMPS family of phosphorothioate cAMP analogs, in which the equatorial exocyclic oxygen of cAMP is replaced by sulfur. It is also known that the diastereoisomer (S(p))-cAMPS with opposite phosphorous chirality is a cAMP agonist, but the molecular mechanism of action of these analogs is currently not fully understood. Previous crystallographic and unfolding investigations point to the enhanced CBD dynamics as a key determinant of antagonism. Here, we investigate the (R(p))- and (S(p))-cAMPS-bound states of R(CBD-A) using a comparative NMR approach that reveals a clear chemical shift and dynamic NMR signature, differentiating the (S(p))-cAMPS agonist from the (R(p))-cAMPS antagonist. Based on these data, we have proposed a model for the (R(p)/S(p))-cAMPS antagonism and agonism in terms of steric and electronic effects on two main allosteric relay sites, Ile(163) and Asp(170), respectively, affecting the stability of a ternary inhibitory complex formed by the effector ligand, the regulatory and the catalytic subunits of protein kinase A. The proposed model not only rationalizes the existing data on the phosphorothioate analogs, but it will also facilitate the design of novel cAMP antagonists and agonists.     

Rapid recovery of serratus anterior muscle function after microneurolysis of long thoracic nerve injury

Background

Injury to the long thoracic nerve is a common cause of winging scapula. When the serratus anterior muscle is unable to function, patients often lose the ability to raise their arm overhead on the affected side.

Methods

Serratus anterior function was restored through decompression, neurolysis, and tetanic electrical stimulation of the long thoracic nerve. This included partial release of constricting middle scalene fibers and microneurolysis of epineurium and perineurium of the long thoracic nerve under magnification. Abduction angle was measured on the day before and the day following surgery.

Results

In this retrospective study of 13 neurolysis procedures of the long thoracic nerve, abduction is improved by 10% or greater within one day of surgery. The average improvement was 59° (p < 0.00005). Patients had been suffering from winging scapula for 2 months to 12 years. The improvement in abduction is maintained at last follow-up, and winging is also reduced.

Conclusion

In a notable number of cases, decompression and neurolysis of the long thoracic nerve leads to rapid improvements in winging scapula and the associated limitations on shoulder movement. The duration of the injury and the speed of improvement lead us to conclude that axonal channel defects can potentially exist that do not lead to Wallerian degeneration and yet cause a clear decrease in function.     

Amide hydrolyzing potential of amidase from halotolerant bacterium Brevibacterium sp. IIIMB2706

Till date, amidases from halophiles and halotolerant micro-organisms have not been much explored. In the present study, Brevibacterium sp. IIIMB2706 strain was isolated from salt fields of Gujarat, India, using propionitrile as a nitrogen source in the mineral base media and explored for its amidase activity. Amidase from Brevibacterium sp. IIIMB2706 exhibited substrate affinity towards isobutyramide, propionamide and butyramide. The optimum temperature and pH required for its maximum activity was 45?°C and 7.0, respectively. Effect of salt concentration on amidase activity was also studied and maximum activity was observed in presence of 50?g L^?1 NaCl with significant activity up to 200?g L^?1 NaCl which justifies its halotolerant nature. Various organic solvents compatibility profile showed that the enzyme was highly active in presence of 10% methyl alcohol. Henceforth, halotolerant enzymes may find application in industrial processes where substrate requires organic solvents for solubilization.     

Synthesis of novel 3-(1-(1-substituted piperidin-4-yl)-1H-1,2,3-triazol-4-yl)-1,2,4-oxadiazol-5(4H)-one as antifungal agents

A novel series of 1,2,3 triazole compounds possessing 1,2,4 oxadiazole ring were efficiently synthesized. Synthesized compounds were evaluated for their in vitro antifungal activities using standard cup plate method. SAR for the series has been developed by comparing their MIC values with miconazole and fluconazole. Compound 11a from the series was more potent than miconazole against Candida albicans (MIC-20) and Aspergillus flavus (MIC-10) whereas equipotent with miconazole against Fusarium oxysporum (MIC-25) and Aspergillus niger (MIC-12.5). Also compound 11h was more potent than miconazole against Candida albicans (MIC-20) and Aspergillus niger (MIC-10) and equipotent with miconazole against Fusarium oxysporum. Compound 11h was equipotent with fluconazole against Aspergillus niger (MIC-10).