An unnatural biopolymer

A highly efficient method has been developed for the solid-phase synthesis of an "unnatural biopolymer" consisting of chiral aminocarbonate monomers linked via a carbamate backbone. Oligocarbamates were synthesized from N-protected p-nitrophenyl carbonate monomers, substituted with a variety of side chains, with greater than 99 percent overall coupling efficiencies per step. A spatially defined library of oligocarbamates was generated by using photochemical methods and screened for binding affinity to a monoclonal antibody. A number of high-affinity ligands were then synthesized and analyzed in solution with respect to their inhibition concentration values, water/octanol partitioning coefficients, and proteolytic stability. These and other unnatural polymers may provide new frameworks for drug development and for testing theories of protein and peptide folding and structure.

Engineering of 2D transition metal carbides and nitrides MXenes for cancer therapeutics and diagnostics

The 2D layered structured material with unique surface terminations and properties have showed great potential in variety of biomedical research fields including drug delivery and cancer therapeutics which forms the major focus of this review. MXenes as a multifunctional two-dimensional (2D) nanomaterial, has also received momentous research interest in oncology resulting from its intriguing structure and fascinating properties of magnetism and photodynamic properties such as luminescent, conductivity, magnetism, non-toxicity and its bio compatibility. This reported review intends to cover exclusively the synthesis and utilization of MXenes in oncological applications, and subsequently its future outlook in cancer therapeutic, diagnostic and theranostics. The versatile and unique physio-chemistry of MXenes permits fine tuning of its properties towards oncological applications ranging from the cancer therapeutic (e.g., photothermal therapy, photodynamic therapy, radiation therapy, chemotherapy) to cancer imaging (e.g., CT/MRI/PA imaging) as well as cancer theranostic applications. We have started the discussion by portraying the broad picture of physio-chemical aspects of MXenes followed by its drug delivery functionalities. Subsequently, ROS mediated therapeutic strategies of photodynamic therapy and radiotherapy as well as light triggered functionalities of MXenes were detailed comprehensively. In the middle of the gallery, various imaging and sensing aspects of MXenes were elucidated. Finally, we have concluded by explaining the combined therapy and diagnostic functions (theranostics) of MXenes. To put it in perspective, the current challenges and new opportunities in MXenes also discussed will give great realistic insights to motivate further research in realizing MXene as an intelligent oncological tool.

Multidrug resistant proteins: P-glycoprotein and lung resistance protein expression in retinoblastoma

BACKGROUND/AIM

Retinoblastoma is the commonest primary intraocular tumour in children. Chemotherapy now plays a big part in the treatment of these tumours. There is not much information about the role of the multidrug resistance proteins (MDR)-P-glycoprotein (P-gp) and vault protein lung resistance protein (LRP)-in retinoblastoma. The authors investigated the expression of P-gp and LRP in retinoblastoma and correlated them clinicopathologically.

METHODS

Among 60 retinoblastomas, 40 tumours were not subjected to preoperative or postoperative chemotherapy and 20 tumours were subjected to postoperative chemotherapy. In this cohort 27 tumours had no invasion and 33 tumours had invasion of choroid, optic nerve, and orbit. P-gp and LRP expression were studied by immunohistochemistry. Immunoanalysis was done semiquantitatively.

RESULTS

Among the 60 tumours P-gp was expressed in 23 (38%) tumours and LRP was expressed in 35 (58%). P-gp was expressed in 11/27 (40%) tumours with no invasion and in 12/33 (36%) tumours with invasion. LRP was expressed in 15/27 (55%) tumours with no invasion and in 20/33 (60%) tumours with invasion. Both P-gp and LRP were negative in three tumours with invasion, which had later developed bone marrow metastasis. There was no correlation between P-gp and LRP expression with invasion, differentiation and laterality of the tumours and response to treatment.

CONCLUSION

Retinoblastoma expresses P-gp and LRP intrinsically before chemotherapy and none of these proteins predicted the response to chemotherapy. Thus, further studies are needed to understand the significance of the expression of the P-gp and LRP proteins in retinoblastoma.

Advanced nanomaterials for hypoxia tumor therapy: challenges and solutions

In recent years, nanomaterials and nanotechnology have emerged as vital factors in the medical field with a unique contribution to cancer medicine. Given the increasing number of cancer patients, it is necessarily required to develop innovative strategies and therapeutic modalities to tackle hypoxia, which forms a hallmark and great barrier in treating solid tumors. The present review details the challenges in nanotechnology-based hypoxia, targeting the strategies and solutions for better therapeutic performances. The interaction between hypoxia and tumor is firstly introduced. Then, we review the recently developed engineered nanomaterials towards multimodal hypoxia tumor therapies, including chemotherapy, radiotherapy, and sonodynamic treatment. In the next part, we summarize the nanotechnology-based strategies for overcoming hypoxia problems. Finally, current challenges and future directions are proposed for successfully overcoming the hypoxia tumor problems.

Retention and tissue distribution of 210Pb (NO3)2 administered orally to infant and adult monkeys

The retention and tissue distribution of 210Pb were studied in 10-day-old, 150-day-old, and adult monkeys. Lead-210 nitrate was administered to the monkeys by gavage after a 12 hr fast and 210Pb excreted in urine and feces was monitored for 96 hr. All monkeys were necropsied 96 hr after dosing and the 210Pb concentrations of various tissues was determined. The data demonstrated that infant monkeys retained 64.5 and 69.8% of the orally administered 210Pb at 10 and 150 days of age, respectively, while adult monkeys retained 3.2% of the 210Pb dose. Blood 210Pb levels 96 hr after dosing did not vary significantly between age groups. Of the 210Pb contained in blood, 98-99% was found in blood cells and 1-2% in blood plasma; 5-8% of the Pb in blood cells was bound to blood cell membranes. None of these parameters varied significantly with age. The percentage of the lead dose excreted in urine did not vary significantly between age groups. Analysis of tissues for 210Pb revealed that both the tissue Pb concentrations and tissue Pb:blood Pb ratios were significantly higher in the bone structure of infants than adults. Brain Pb:blood Pb ratios were significantly greater in 10-day-old infants than 150-day-old infants or adults.

Fabrication of tri-layered electrospun polycaprolactone mats with improved sustained drug release profile

Modulation of initial burst and long term release from electrospun fibrous mats can be achieved by sandwiching the drug loaded mats between hydrophobic layers of fibrous polycaprolactone (PCL). Ibuprofen (IBU) loaded PCL fibrous mats (12% PCL-IBU) were sandwiched between fibrous polycaprolactone layers during the process of electrospinning, by varying the polymer concentrations (10% (w/v), 12% (w/v)) and volume of coat (1 ml, 2 ml) in flanking layers. Consequently, 12% PCL-IBU (without sandwich layer) showed burst release of 66.43% on day 1 and cumulative release (%) of 86.08% at the end of 62 days. Whereas, sandwich groups, especially 12% PCLSW-1 & 2 (sandwich layers-1 ml and 2 ml of 12% PCL) showed controlled initial burst and cumulative (%) release compared to 12% PCL-IBU. Moreover, crystallinity (%) and hydrophobicity of the sandwich models imparted control on ibuprofen release from fibrous mats. Further, assay for cytotoxicity and scanning electron microscopic images of cell seeded mats after 5 days showed the mats were not cytotoxic. Nuclear Magnetic Resonance spectroscopic analysis revealed weak interaction between ibuprofen and PCL in nanofibers which favors the release of ibuprofen. These data imply that concentration and volume of coat in flanking layer imparts tighter control on initial burst and long term release of ibuprofen.

Abnormal amyloid β42 expression and increased oxidative stress in plasma of CKD patients with cognitive dysfunction: A small scale case control study comparison with Alzheimer's disease

Background

Cognitive dysfunction has been increasingly recognized in chronic kidney disease (CKD) patients. Senile plaques are important pathophysiological characteristic of cognitive dysfunction. The major component of plaques is the amyloid β (Aβ) peptide released from proteolytic cleavage of amyloid precursor protein (APP). Plasma Aβ has been a focus of the growing literature on blood based biomarkers for cognitive dysfunction. Oxidative stress is prevalent in CKD and it plays an important role in cognitive dysfunction. Increased oxidative stress leads to cause cleavage of APP and Aβ production. The aim of this study is to assess the antioxidant status and Aβ₄₂ levels in plasma of CKD patients with cognitive dysfunction compared to CKD without cognitive dysfunction.

Methods

A total of 60 subjects divided into 30 CKD without cognitive dysfunction and 30 CKD with cognitive dysfunction based on neuropsychological assessment tests. To compare antioxidant status and Aβ₄₂ levels in plasma, the following groups such as healthy subjects (n = 30), normocytic normochromic anemia (n = 30) and Alzheimer's disease (AD, n = 10) patients were also maintained. Plasma Superoxide dismutase (SOD), Catalase (CAT), Glutathione peroxidase (GPx), Reduced glutathione (GSH) and lipid peroxidation (LPO) were determined by spectrophotometrically. Aβ level was determined by immunoblotting method. The parameters were statistically compared with healthy, normocytic normochromic anemia and AD subjects.

Results

Like AD subjects, significantly increased Aβ and LPO level while decreased SOD, CAT, GPx and GSH levels were observed in plasma of CKD patients with cognitive dysfunction when compared to healthy, CKD without cognitive dysfunction and normocytic normochromic anemic subjects.

Conclusion

Results suggest that elevated plasma oxidative stress and Aβ were seen in CKD patients with cognitive dysfunction may be attributed to pathological changes within the brain.

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Cognitive dysfunction has been increasingly recognized in chronic kidney disease (CKD) patients.

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The major component of plaques is the amyloid β peptide released from proteolytic cleavage of amyloid precursor protein.

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Plasma Aβ has been a focus of the growing literature on blood based biomarkers for cognitive dysfunction.

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Oxidative stress is prevalent in CKD and it plays an important role in cognitive dysfunction.

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Increased oxidative stress leads to cause cleavage of APP and Aβ production.

Subchronic toxicity of photomirex in the female rat: results of 28- and 90-day feeding studies

Photomirex (8-monohydromirex) was administered to female Sprague-Dawley rats at dietary levels of 0.2, 1.0, 5.0, 25.0 and 125 ppm. Food intake and body weight gain were significantly depressed at the 125 ppm level in the 28- but not in the 90-day study. Significant alterations were observed in some hematological and biochemical parameters at the highest dietary level in the 90-day study. Photomirex residues accumulated in a dose-dependent manner in perirenal fat, liver, brain, kidney, and spleen. Dose-dependent histotoxic effects were observed in liver and thyroid at and above 1 ppm; hepatomegaly was observed at 25.0 and 125 ppm. These results indicate that photomirex was approximately five times more toxic than mirex in terms of liver histology. When these results are compared with those observed in an earlier study in the male rat, it is evident that the female is less susceptible to photomirex than the male.

Two-dimensional nanostructures based '-onics' and '-omics' in personalized medicine

With the maturing techniques for advanced synthesis and engineering of two-dimensional (2D) materials, its nanocomposites, hybrid nanostructures, alloys, and heterostructures, researchers have been able to create materials with improved as well as novel functionalities. One of the major applications that have been taking advantage of these materials with unique properties is biomedical devices, which currently prefer to be decentralized and highly personalized with good precision. The unique properties of these materials, such as high surface to volume ratio, a large number of active sites, tunable bandgap, nonlinear optical properties, and high carrier mobility is a boon to 'onics' (photonics/electronics) and 'omics' (genomics/exposomics) technologies for developing personalized, low-cost, feasible, decentralized, and highly accurate medical devices. This review aims to unfold the developments in point-of-care technology, the application of 'onics' and 'omics' in point-of-care medicine, and the part of two-dimensional materials. We have discussed the prospects of photonic devices based on 2D materials in personalized medicine and briefly discussed electronic devices for the same.

Influence of Field Position on Rugby League Players Requiring Shoulder Reconstruction

A consecutive series of patients sustaining their index anterior instability while playing Rugby League and requiring shoulder reconstruction was retrospectively reviewed and evaluated. The details of their on-field position and hand dominance at time of injury, the side of injury, and mechanism of injury were collated and statistically analyzed. A total of 173 Bankart repairs were performed on 132 patients, and 102 players had one injury while 30 had 2 or more injuries. Players are more likely to injure their non-dominant side (P=0.009) in the first-time injury. Whereas second and subsequent injuries were not associated with a particular side (P=0.81). Applying a Bonferroni correction to the chi-squared goodness-of-fit test of position at time of injury revealed players on the wing had a significantly lower frequency of injury (P<0.001), whereas the full back had a significantly higher frequency of injury (P<0.001). 30 players sustained 69 re-dislocations with the lock and fullback positions incurring significantly more re-injuries and the wing position fewer re-injuries than expected (P<0.006). Understanding which player positions on the rugby league field are more likely to sustain an anterior instability will assist medical and support staff to optimize the pre-season conditioning and post surgical rehabilitation of players.

Triple-action cancer therapy using laser-activated NO-releasing metallomicellar nanophotosensitizer for pyroptosis-driven immune reprogramming

Cancer photoimmunotherapy represents an intelligent and highly efficient therapeutic approach that harnesses the photothermal effect to precisely target and ablate tumor tissues, while simultaneously modulating the immune system to achieve tumor elimination. The integration of multifunctional therapeutic modalities for combined photoimmunotherapy requires advanced drug delivery systems. However, the design of a single nanoagent capable of serving as a multifunctional nanophotosensitizer remains a significant challenge. In this study, we developed a metallomicellar nanophotosensitizer named TAGNO, which offers a synergistic tri-modal cancer treatment strategy by combining photothermal therapy (PTT), gas therapy (GT), and immunotherapy. The TAGNO nanophotosensitizer consists of a gold nanorod core, responsible for inducing the photothermal effect, coated with an amphiphilic polymer functionalized with tumor cell penetrating peptide to accommodate lipophilic small molecule BNN6, a nitric oxide (NO) donor for GT. We demonstrated that TAGNO exhibited high tumor accumulation, excellent stability, and biocompatibility, ensuring the safe delivery of NO to the tumor site. Upon near-infrared (NIR) laser irradiation, TAGNO effectively raised the temperature within tumor tissues while sparing the surrounding healthy tissues and enabled controlled NO release. Once released, the NO interacts with hydrogen peroxide in the hypoxic tumor microenvironment, forming peroxynitrite (ONOO-), which induces mitochondrial dysfunction and triggers pyroptotic cell death. Pyroptosis induced immunogenic cell death and the subsequent release of tumor antigens, activating cytotoxic T cells and promoting M1 macrophage polarization, effectively controlling both primary and secondary tumor growth. Furthermore, laser-induced NO release facilitated the relaxation of stiff tumor tissues, enhancing blood vessel dilation and oxygenation. This improvement promoted immune cell infiltration while suppressing immunosuppressive cells. Overall, this innovative combination of PTT, GT, and immunotherapy presents a potent and synergistic strategy for the treatment of malignant colon tumors, achieving complete tumor eradication.