Polystyrene microplastic-induced endoplasmic reticulum stress contributes to growth plate endochondral ossification disorder in young rat.

BACKGROUND: Previous studies on the effects of microplastics (MPs) on bone in early development are limited. This study aimed to investigate the adverse effects of MPs on bone in young rats and the potential mechanism. METHODS: Three-week-old female rats were orally administered MPs for 28 days, and endoplasmic reticulum (ER) stress inhibitor salubrinal (SAL) and ER stress agonist tunicamycin (TM) were added to evaluate the effect of ER stress on toxicity of MPs. The indicators of growth and plasma markers of bone turnover were evaluated. Tibias were analyzed using micro-computed tomography (micro-CT). Histomorphological staining of growth plates was performed, and related gene expression of growth plate chondrocytes was tested. RESULTS: After exposure of MPs, the rats had decreased growth, shortened tibial length, and altered blood calcium and phosphorus metabolism. Trabecular bone was sparse according to micro-CT inspection. In the growth plate, the thickness of proliferative zone substantial reduced while the thickness of hypertrophic zone increased significantly, and the chondrocytes were scarce and irregularly arranged according to tibial histological staining. The transcription of the ER stress-related genes BIP, PERK, ATF4, and CHOP dramatically increased, and the transcription factors involved in chondrocyte proliferation, differentiation, apoptosis, and matrix secretion were aberrant according to RT-qPCR and western blotting. Moreover, the addition of TM showed higher percentage of chondrocyte death. Administration of SAL alleviated all of the MPs-induced symptoms. CONCLUSION: These results indicated that MPs could induce growth retardation and longitudinal bone damage in early development. The toxicity of MPs may attribute to induced ER stress and impaired essential processes of the endochondral ossification after MPs exposure.

Anatase and Rutile TiO2 Nanoparticles Lead Effective Bone Damage in Young Rat Model via the IGF-1 Signaling Pathway.

PURPOSE: To evaluate the effects of anatase and rutile TiO2 nanoparticles (NPs) on the growth and development of bones in young rats and explore their possible mechanisms. METHODS: Three-week-old male rats were orally administered anatase TiO2 NPs and rutile TiO2 NPs for 28 days. The indicators of rat growth and development, liver function, bone metabolism, and insulin-like growth factor-1 (IGF-1) levels were evaluated. Micro-computed tomography (micro-CT) and immunohistochemistry were used to evaluate the tibia. RESULTS: No significant differences were observed among growth and development indicators in young rats. Significant differences were found in IGF-1 levels, phosphorus levels, and liver function. Micro-CT revealed osteoporosis in the bones. The micro-CT data supported the same result. Bone immunohistochemistry results showed that the expression of osteoprotegerin (OPG) was decreased and the expression of receptor activator of nuclear factor-κB ligand (RANKL) and cathepsin K (CTSK) was increased. CONCLUSION: This study demonstrated that TiO2 NPs can damage bones via the IGF-1/OPG/RANKL/CTSK pathway in young rats. Furthermore, rutile TiO2 NPs damaged the bones more seriously than anatase TiO2 NPs.

Acute Generalized Exanthematous Pustulosis Induced by Cetuximab.

A wide variety of diseases and drugs can cause cutaneous pustular eruptions. Acute generalized exanthematous pustulosis (AGEP) is a unique drug-induced dermatosis clinically presented as erythematous papular and pustular eruption, usually caused by certain systemic drugs. We are presenting a very rare association of AGEP with a biological agent, cetuximab. A male aged 66 years, who was recently diagnosed with a case of squamous cell carcinoma of glottis, presented in the dermatology clinic with a recent onset of fever and widespread pustular eruption over the face, trunk, and limbs. The eruption was noted after the injection of cetuximab given for his squamous cell carcinoma. The clinical history, typical physical findings, and histopathological features confirm the diagnosis of AGEP. The injection cetuximab was stopped and the patient was treated with some topical and systemic medications and the symptoms resolved completely in a few weeks. Our case is an interesting clinical presentation of AGEP due to cetuximab therapy and confirms that this is an extremely rare and proven adverse effect of cetuximab. To our knowledge, this is the first-ever reported case of AGEP associated with cetuximab. Physicians need to be aware of this unique but important side effect of cetuximab and perform a proper physical examination and specific investigations that can be useful to reach a final diagnosis.

Hypomethylating agents+venetoclax induction therapy in acute myeloid leukemia unfit for intensive chemotherapy - novel avenues for lesser venetoclax duration and patients with baseline infections from a developing country.

Both elderly acute myeloid leukemia (AML) patients and those with baseline infections, when treated with intensive chemotherapy, are associated with high induction mortality. We report 24 patients (16-newly-diagnosed, 8-relapsed/refractory) with AML deemed unfit for intensive chemotherapy (by virtue of age >60 years, ECOG-PS 3-4, or those with non-resolving infections at baseline), treated with azacytidine-venetoclax combination as induction chemotherapy. Median follow-up of the study group was 8 months. The overall complete remission (CR)+CR with incomplete count recovery (CRi) rate was 58.3%. 1-year progression-free survival and overall survival of the whole cohort was 44.4% and 55.8%, respectively. On subgroup analysis, newly-diagnosed AML (p=0.05), intermediate-risk cytogenetics (p=0.007), and HMA-naïve (p=0.05) patients had a significantly better outcome. AML patients with baseline infections (versus without infections) treated with azacytidine-venetoclax induction, have lesser induction mortality (compared with historic intensive chemotherapy) with equivalent response rates. A detailed analysis amongst cohorts with different venetoclax durations revealed that, shorter duration (<21 days) venetoclax (versus 21-28 days duration) in induction therapy leads to similar response rates and similar severity of myelosuppression, however, with early count recovery and lesser duration of intravenous antibiotics.

Development of Electrochemical DNA Biosensor for Equine Hindgut Acidosis Detection.

The pH drop in the hindgut of the horse is caused by lactic acid-producing bacteria which are abundant when a horse's feeding regime is excessively carbohydrate rich. This drop in pH below six causes hindgut acidosis and may lead to laminitis. Lactic acid-producing bacteria Streptococcus equinus and Mitsuokella jalaludinii have been found to produce high amounts of L-lactate and D-lactate, respectively. Early detection of increased levels of these bacteria could allow the horse owner to tailor the horse's diet to avoid hindgut acidosis and subsequent laminitis. Therefore, 16s ribosomal ribonucleic acid (rRNA) sequences were identified and modified to obtain target single stranded deoxyribonucleic acid (DNA) from these bacteria. Complementary single stranded DNAs were designed from the modified target sequences to form capture probes. Binding between capture probe and target single stranded deoxyribonucleic acid (ssDNA) in solution has been studied by gel electrophoresis. Among pairs of different capture probes and target single stranded DNA, hybridization of Streptococcus equinus capture probe 1 (SECP1) and Streptococcus equinus target 1 (SET1) was portrayed as gel electrophoresis. Adsorptive stripping voltammetry was utilized to study the binding of thiol modified SECP1 over gold on glass substrates and these studies showed a consistent binding signal of thiol modified SECP1 and their hybridization with SET1 over the gold working electrode. Cyclic voltammetry and electrochemical impedance spectroscopy were employed to examine the binding of thiol modified SECP1 on the gold working electrode and hybridization of thiol modified SECP1 with the target single stranded DNA. Both demonstrated the gold working electrode surface was modified with a capture probe layer and hybridization of the thiol bound ssDNA probe with target DNA was indicated. Therefore, the proposed electrochemical biosensor has the potential to be used for the detection of the non-synthetic bacterial DNA target responsible for equine hindgut acidosis.

Gold-microrods/Pd-nanoparticles/polyaniline-nanocomposite-interface as a peroxidase-mimic for sensitive detection of tropomyosin.

In this study, Gold-microrods (AuMRs), Pd-nanoparticles (PdNPs), and Polyaniline (PANI) nanocomposite-interface was fabricated on the screen-printed carbon-microelectrode (SPE). Each layer of the interface was characterised using field emission-scanning electron microscopy (FE-SEM) and cyclic voltammetry (CV). The fabricated SPE/AuMRs/PdNPs/PANI interface demonstrated the highest electronic current and showed excellent peroxidase-mimic towards H2O2 using chronoamperometry (CA). Furthermore, the SPE/AuMRs/PdNPs/PANI interface was utilised for the construction of a highly sensitive label-free electrochemical biosensor for the detection of Tpm in seafood samples. Label-free electrochemical detection of the Tpm was performed using both CA and differential pulse voltammetry (DPV) techniques. Preliminary data showed that both methods could detect Tpm as low as 0.01 pg/mL. Moreover, the developed biosensor for the detection of Tpm demonstrated excellent selectivity, high reproducibility and longer stability with an evident potential to detect Tpm in real seafood samples.

AuNPs/CNOs/SWCNTs/chitosan-nanocomposite modified electrochemical sensor for the label-free detection of carcinoembryonic antigen.

In this work, a nanocomposite of gold nanoparticles (AuNPs), carbon nano-onions (CNOs), single-walled carbon nanotubes (SWCNTs) and chitosan (CS) (AuNPs/CNOs/SWCNTs/CS) was prepared for the development of highly sensitive electrochemical immunosensor for the detection of carcinoembryonic antigen (CEA), clinical tumor marker. Firstly, layer-by-layer fabrication of the CEA-immunosensors was studied using cyclic voltammetry (CV) and square wave voltammetry (SWV). By combining the advantages of large surface area and electronic properties of AuNPs, CNOs, SWCNTs, and film forming properties of CS, AuNPs/CNOs/SWCNTs/CS-nanocomposite-modified glassy carbon electrode showed a 200% increase in effective surface area and electronic conductivity. The calibration plot gave a negative linear relationship between log[concentration] of CEA and electrical current with a correlation coefficient of 0.9875. The CEA-immunosensor demonstrated a wide linear detection range of 100 fg mL-1 to 400 ng mL-1 with a low detection limit of 100 fg mL-1. In addition to high sensitivity, reproducibility and large stability, CEA-immunosensor provided an excellent selectivity and resistant-to-interference in the presence of other antigens in serum and hence a potential to be used with real samples.

Trends and Advances in Electrochemiluminescence Nanobiosensors.

The rapid and increasing use of the nanomaterials (NMs), nanostructured materials (NSMs), metal nanoclusters (MNCs) or nanocomposites (NCs) in the development of electrochemiluminescence (ECL) nanobiosensors is a significant area of study for its massive potential in the practical application of nanobiosensor fabrication. Recently, NMs or NSMs (such as AuNPs, AgNPs, Fe3O4, CdS QDs, OMCs, graphene, CNTs and fullerenes) or MNCs (such as Au, Ag, and Pt) or NCs of both metallic and non-metallic origin are being employed for various purposes in the construction of biosensors. In this review, we have selected recently published articles (from 2014-2017) on the current development and prospects of label-free or direct ECL nanobiosensors that incorporate NCs, NMs, NSMs or MNCs.

Mucoadhesive elementary osmotic pump tablets of trimetazidine for controlled drug delivery and reduced variability in oral bioavailability.

The objectives of this work was preparation and evaluation of the mucoadhesive elementary osmotic pump tablets of trimetazidine hydrochloride to achieve desired controlled release action and augmentation of oral drug absorption. The drug-loaded core tablets were prepared employing the suitable tableting excipients and coated with polymeric blend of ethyl cellulose and hydroxypropyl methylethylcellulose E5 (4:1). The prepared tablets were characterized for various quality control tests and in vitro drug release. Evaluation of drug release kinetics through model fitting suggested the Fickian mechanism of drug release, which was regulated by osmosis and diffusion as the predominant mechanism. Evaluation of mucoadhesion property using texture analyzer suggested good mucoadhesion potential of the developed osmotic systems. Solid state characterization using Fourier-transform infrared spectroscopy, differential scanning calorimetry and powder X-ray diffraction spectroscopy confirmed the absence of any physiochemical incompatibilities between drug and excipients. Scanning electron microscopy analysis showed the smooth surface appearance of the coated tablets with intact polymeric membrane without any fracture. In vivo pharmacokinetic studies in rabbits revealed 3.01-fold enhancement in the oral bioavailability vis-à-vis the marketed formulation (Vastarel MR®). These studies successfully demonstrate the bioavailability enhancement potential of the mucoadhesive elementary osmotic pumps as novel therapeutic systems for other drugs too.

Development of solid self-nanoemulsifying granules (SSNEGs) of ondansetron hydrochloride with enhanced bioavailability potential.

The current work aims to prepare the solid self-nanoemulsifying granules (SSNEGs) of ondansetron hydrochloride (ONH) to enhance its oral bioavailability by improving its aqueous solubility and facilitating its absorption though lymphatic pathways. Preformulation studies including screening of excipients for solubility and pseudoternary phase diagrams suggested the suitability of Capmul MCM as lipid, Labrasol as surfactant, and Tween 20 as cosurfactant for preparation of self-emulsifying formulations. Preliminary composition of the SNEDDS formulations were selected from the phase diagrams and subjected to thermodynamic stability studies and dispersibility tests. The prepared liquid SNEDDS formulations were characterized for viscosity, refractive index, droplet size and zeta potential. The TEM study confirmed the formation of nanoemulsion following dilution of liquid SNEDDS. The optimized liquid SNEDDS were transformed into free flowing granules by adsorption on the porous carriers like Sylysia (350, 550, and 730) and Neusilin™ US2. Solid state characterization employing the FTIR, DSC and powder XRD studies indicated lack of any significant interaction of drug with the lipidic and emulsifying excipients, and porous carriers. In vitro drug release studies indicated faster solubilization of the drug by optimized SSNEGs (over 80% within 30 min) vis-à-vis the pure drug (only 35% within 30 min). In vivo pharmacokinetic studies in Wistar rats observed significant increase in C(max) (3.01-fold) and AUC (5.34-fold) using SSNEGs compared to pure drug, whereas no significant difference (p>0.1) was observed with the liquid SNEDDS. Thus, the present studies ratify the bioavailability enhancement potential of SSNEGs of ONH prepared using porous carriers.

Assessment of isomalt for colon-specific delivery and its comparison with lactulose.

Lactulose is used as a triggering substance in a unique colon-specific delivery technology called CODESTM. Colonic microflora degrades lactulose and forms short-chain fatty acids to activate the CODESTM system. However, lactulose has been reported to cause a Maillard-type reaction with substances containing primary or secondary amino groups that may produce carcinogenic compounds. Thus, the aim of this study was to look into the possibility to substitute lactulose with isomalt for fabrication of CODESTM. The in vitro degradation of both sugars before incorporating them into the CODESTM system was evaluated with the help of rat caecal microflora. The results showed that isomalt was less efficient with regard to its rate and extent of degradation into short-chain fatty acids by the microflora compared to lactulose. However, the in vitro dissolution study did not show a significant difference in the performance between lactulose and isomalt when they were incorporated separately in CODESTM. A similar result was also obtained in the in vivo study. Based on the above results, isomalt could be used as an alternative to lactulose for colonic delivery system utilizing the principles of CODESTM.

Advancement in carbon nanotubes: basics, biomedical applications and toxicity.

OBJECTIVES: Carbon nanotubes (CNTs) have attracted much attention by researchers worldwide in recent years for their small dimensions and unique architecture, and for having immense potential in nanomedicine as biocompatible and supportive substrates, as a novel tool for the delivery of therapeutic molecules including peptides, RNA and DNA, and also as sensors, actuators and composites. KEY FINDINGS: CNTs have been employed in the development of molecular electronic, composite materials and others due to their unique atomic structure, high surface area-to-volume ratio and excellent electronic, mechanical and thermal properties. Recently they have been exploited as novel nanocarriers in drug delivery systems and biomedical applications. Their larger inner volume as compared with the dimensions of the tube and easy immobilization of their outer surface with biocompatible materials make CNTs a superior nanomaterial for drug delivery. Literature reveals that CNTs are versatile carriers for controlled and targeted drug delivery, especially for cancer cells, because of their cell membrane penetrability. SUMMARY: This review enlightens the biomedical application of CNTs with special emphasis on utilization in controlled and targeted drug delivery, as a diagnostics tool and other possible uses in therapeutic systems. The review also focuses on the toxicity aspects of CNTs, and revealed that genotoxic potential, mutagenic and carcinogenic effects of different types of CNTs must be explored and overcome by formulating safe biomaterial for drug delivery. The review also describes the regulatory aspects and clinical and market status of CNTs.

Enhanced transdermal drug delivery techniques: an extensive review of patents.

Transdermal drug delivery system has been accepted as potential non-invasive route of drug administration, with advantages of avoidance of the first-pass metabolism, sustained therapeutic action and better patient compliance, though, its prevalent use is restricted due to excellent impervious nature of skin. It is the greatest challenge for researchers to surmount the inherent limitations imposed by stratum corneum of skin, for enhanced transdermal drug delivery to achieve systemic therapeutic concentration. Thus, many approaches have been attempted to perturb skin barrier and enhance the transdermal delivery of drug. The major approaches for enhancing transdermal delivery are physical enhancers (ultrasound, iontophoresis, electroporation, magnetophoresis, microneedle), vesicles, particulate systems (liposome, niosome, transfersome, microemulsion, solid lipid nanoparticle) and chemical enhancers (sulphoxides, azones, glycols, alkanols, terpenes etc.). The present review explores recent patents on techniques employed to breach the skin barrier for drug permeation along with their penetration enhancement mechanisms.

Emerging role of microemulsions in cosmetics.

Microemulsions represent a promising carrier system for cosmetic active ingredients due to their numerous advantages over the existing conventional formulations. They are capable of solubilizing both hydrophilic and lipophilic ingredients with relatively higher encapsulation. There is growing recognition of their potential benefits in the field of cosmetic science in addition to the drug delivery. They are now being widely investigated for preparing personal care products with superior features such as having improved product efficiency, stability or appearance. They are well suited for the preparation of various cosmetic products for use as moisturizing and soothing agents, as sunscreens, as antiperspirants and as body cleansing agents. They are also valuable for use in hair care compositions which ensure a good conditioning of the hair as well as good hair feel and hair gloss. They have also found application in after shave formulations which upon application to the skin provide reduced stinging and irritation and a comforting effect without tackiness. These newer formulations elicit very good cosmetic attributes and high hydration properties with rapid cutaneous penetration which may accentuate their role in topical products. These smart systems are also suitable for perfuming purposes where minimum amount of organic solvents is required, such as for perfuming skin or hair. This article highlights the recent innovations in the field of microemulsion technology as claimed by different patents which can bring unique products with great commercial prospects in a very competitive and lucrative global cosmetic market.

Transdermal delivery of valsartan: I. Effect of various terpenes.

The objective of the present study was to investigate the effect of various terpenes, including a diterpene, forskolin (FSK; a putative penetration enhancer), on skin permeation of valsartan. Permeation studies were carried out with Automated Transdermal Diffusion Cells Sampling System (SFDC 6, LOGAN Instruments Corp., NJ, USA) through rat skin and human cadaver skin (HCS) using ethanol: IPB (pH 7.4) (40:60) as vehicle. The efficacy of the study terpenes for permeation of valsartan across rat skin and human cadaver skin was found in the order of cineole > d-limonene > l-menthol > linalool > FSK and cineole > d-limonene > linalool > l-menthol > FSK, respectively. No apparent skin irritation (erythema, edema) was observed on treatment of skin with terpenes including FSK. FT-IR, DSC, and histopathological studies revealed that FSK enhanced the skin permeation of the active drug by disruption and extraction of lipid bilayers of SC in consonance with other terpenes.

Sulfur toxicity and media capacity for H2S removal in biofilters packed with a natural or a commercial granular medium.

Two types of media, a natural medium (wood chips) and a commercially engineered medium, were evaluated for sulfur inhibition and capacity for removal of hydrogen sulfide (H2S). Sulfate was added artificially (40, 65, and 100 mg of S/g of medium) to test its effect on removal efficiency and the media. A humidified gas stream of 50 ppm by volume H2S was passed through the media-packed columns, and effluent readings for H2S at the outlet were measured continuously. The overall H2S baseline removal efficiencies of the column packed with natural medium remained >95% over a 2-day period even with the accumulated sulfur species. Added sulfate at a concentration high enough to saturate the biofilter moisture phase did not appear to affect the H2S removal process efficiency. The results of additional experiments with a commercial granular medium also demonstrated that the accumulation of amounts of sulfate sufficient enough to saturate the moisture phase of the medium did not have a significant effect on H2S removal. When the pH of the biofilter medium was lowered to 4, H2S removal efficiency did drop to 36%. This work suggests that sulfate mass transfer through the moisture phase to the biofilm phase does not appear to inhibit H2S removal rates in biofilters. Thus, performance degradation for odor-removing biofilters or H2S breakthrough in field applications is probably caused by other consequences of high H2S loading, such as sulfur precipitation.