Dye functionalized cryogel columns for reversible lysozyme adsorption

In this study, poly (methyl methacrylate–glycidyl methacrylate) [poly(MMA-GMA)] cryogels were prepared by radical cryocopolymerization of MMA with GMA as a functional comonomer. Reactive Green 19 dye was then attached to the cryogel by nucleophilic substitution reaction, and this dye-attached cryogel column was used for lysozyme adsorption. Characterization of the cryogel was performed by Fourier transform infrared spectroscopy, environmental scanning electron microscopy, Brunauer–Emmett–Teller, and energy dispersive X-ray analysis. Pore size of the cryogels was 15–30?μm and pores were interconnected structure. Attached amount of Reactive Green 19 to cryogel support was calculated as 106.25?μmol/g cryogel. Lysozyme adsorption studies were carried out by using a continuous system. It was found that the maximum amount of lysozyme adsorption (32?mg/g cryogel) obtained from experimental results was found to be approximately same with the calculated Langmuir adsorption capacity (33?mg/g cryogel). Desorption of adsorbed lysozyme was carried out by using 1.5?M NaCl in pH 4.5 acetate buffer, and desorption yield was found to be 97.4%. Cryogels were very stable, and it was found that there was no remarkable reduction in the adsorption capacity at the end of ten adsorption–desorption cycles. As a result, Reactive Green 19-attached cryogels have great advantages such as easy preparation, rapid adsorption, and desorption, being economic and allowing the direct separation of proteins.     

Immobilization of amyloglucosidase onto macroporous cryogels for continuous glucose production from starch

Poly(methyl methacrylate-glycidyl methacrylate) [Poly(MMA-GMA)] cryogels were synthesized using monomers of methylmethacrylic acid and epoxy group bearing GMA via radical cryopolymerization technique. Synthesized cryogels were used for the immobilization of amyloglucosidase to the cryogel surface using epoxy chemistry. Characterizations of the free and immobilized amyloglucosidase were carried out by comparing the optimum and kinetic parameters of enzymes. For this, pH and temperature profiles of free and immobilized preparation were studied and, it was found that, optimum pH of enzyme was not change upon immobilization (pH 5.0), while optimum temperature of the enzyme shifted 10 °C to warmer region after immobilization (optimum temperatures for free and immobilized enzyme were 55 and 65 °C, respectively). Kinetic parameters of free and immobilized enzyme were also investigated and K_m values of free and immobilized amyloglucosidase were found to be 2.743 and 0.865 mg/mL, respectively. V_max of immobilized amyloglucosidase was found to be (0.496 µmol/min) about four times less than that of free enzyme (2.020 µmol/min). Storage and operational stabilities of immobilized amyloglucosidase were also studied and it was showed that immobilized preparation had much more stability than free preparation. In the present work, amyloglucosidase immobilized poly(MMA-GMA) cryogels were used for continuous glucose syrup production from starch for the first time. Efficiency of immobilized enzyme was investigated and released amount of glucose was found to be 2.54 mg/mL at the end of the 5 min of hydrolysis. The results indicate that the epoxy functionalized cryogels offer a good alternative for amyloglucosidase immobilization applications with increased operational and thermal stability, and reusability. Also, these cryogels can be used for immobilization of other industrially valuable enzymes beyond amyloglucosidase.     

Proteomic characterization of HIV-modulated membrane receptors, kinases and signaling proteins involved in novel angiogenic pathways

Background  

Kaposi's sarcoma (KS), hemangioma, and other angioproliferative diseases are highly prevalent in HIV-infected individuals. While KS is etiologically linked to the human herpesvirus-8 (HHV8) infection, HIV-patients without HHV-8 and those infected with unrelated viruses also develop angiopathies. Further, HIV-Tat can activate protein-tyrosine-kinase (PTK-activity) of the vascular endothelial growth factor receptor involved in stimulating angiogenic processes. However, Tat by itself or HHV8-genes alone cannot induce angiogenesis in vivo unless specific proteins/enzymes are produced synchronously by different cell-types. We therefore tested a hypothesis that chronic HIV-replication in non-endothelial cells may produce novel factors that provoke angiogenic pathways.     

Scleral buckling technique for longstanding inferior rhegmatogenous retinal detachments with subretinal bands.

We investigated the effectiveness and safety of conventional surgery on longstanding retinal detachments (RD) with subretinal bands (SRB). We found that conventional surgery were safe and effective method in the treatment of inferior chronic rhegmatogenous RD cases with SRB without other signs of advanced proliferative vitreopathy. Further studies with larger numbers and longer follow up are needed.     

Nd:YAG Laser Posterior Capsulotomy After Pediatric and Adult Cataract Surgery

We evaluated neodymium-doped yttrium-aluminum-garnet (Nd:YAG) laser posterior capsulotomy procedure with or without anesthesia in 35 pediatric eyes and 51 adult eyes. We concluded that Nd:YAG laser posterior capsulotomies in children are similar to adults in general aspects and that Nd:YAG laser capsulotomy can be performed safely and effectively in children under topical or no anesthesia.     

Intracranial hydatid cyst: contribution of scanography

We reviewed 14 cases of intracranial hydatid cysts, describing the clinical features and radiographic findings. The clinical presentation was dominated by signs of increased intracranial pressure and neurological manifestations. Diagnosis was established on the basis of CT findings, most valuable as a diagnostic tool.     

The multi-institutional validation of the new screening index for physical child abuse

Background/Purpose

There is currently no evidence-based screening instrument to assist in the detection of physical child abuse patients. The screening index for physical child abuse (SIPCA) was previously developed as a potentially new tool for this need. It is a scale that assigns point values, on the basis of variable weights from logistic regression models, to age and patterns of injuries (including fracture of base or vault of skull, contusion of eye, rib fracture, intracranial bleeding, multiple burns), with higher scores indicating greater suspicion for abuse. The purpose of this study is to validate this new tool in another independent data set.

Methods

A cross-sectional hospital discharge database from 1961 hospitals in 17 states is used (n = 58558). Children aged 14 years or younger with International Classification of Diseases, Ninth Revision, Clinical Modification codes 800 to 959 are included for analysis. Child abuse cases are identified by E codes and certain International Classification of Diseases, Ninth Revision, Clinical Modification codes in the 995.5x range. Screening index for physical child abuse performance is evaluated by discrimination (receiver operating characteristic) and goodness of fit (pseudo r²).

Results

A total of 447 abused patients (0.76%) was identified. The receiver operating characteristic of SIPCA in this data set is 0.89 as compared with 0.86 in the development data set. The pseudo r² of SIPCA in this data set is 0.26 as compared with 0.28 in the development data set. A SIPCA score of 3 has a sensitivity of 86.6% and a specificity of 80.5% for detecting physical abuse; raising the threshold to a score of 4 improves the specificity to 93.1% but at a loss of sensitivity to 71.8%.

Conclusions

The validity of the new SIPCA instrument is supported by its performance in an independently derived data set. A score of 3 on SIPCA represents a balanced trade off in the sensitivity and specificity of the instrument in detecting physical abuse and is an optimal threshold above which to begin considering abuse in differential diagnosis. Application of the instrument could assist clinicians in detecting physical child abuse cases among pediatric trauma patients.