Platinum-based chemotherapy: trends in organic nanodelivery systems.

Despite the investment in platinum drugs research, cisplatin, carboplatin and oxaliplatin are still the only Pt-based compounds used as first line treatments for several cancers, with a few other compounds being approved for administration in some Asian countries. However, due to the severe and worldwide impact of oncological diseases, there is an urge for improved chemotherapeutic approaches. Furthermore, the pharmaceutical application of platinum complexes is hindered by their inherent toxicity and acquired resistance. Nanodelivery systems rose as a key strategy to overcome these challenges, with recognized versatility and ability towards improving the safety, bioavailability and efficacy of the available drugs. Among the known nanocarriers, organic systems have been widely applied, taking advantage of their potential as drug vehicles. Researchers have mainly focused on the development of lipidic and polymeric carriers, including supramolecular structures, with an overall improvement of encapsulated platinum complexes. Herein, an overview of recent trends and strategies is presented, with the main focus on the encapsulation of platinum compounds into organic nanocarriers, showcasing the evolution in the design and development of these promising systems. This comprehensive review highlights formulation methods as well as characterization procedures, providing insights that may be helpful for the development of novel platinum nanocarriers aiming at future pharmaceutical applications.

Synchrotron nano-FTIR spectroscopy for probing anticancer drugs at subcellular scale.

The cellular response to cisplatin was assessed in human osteosarcoma cells, using synchrotron-based (SR) Fourier Transform InfraRed nanospectroscopy (nano-FTIR) at the MIRIAM beamline B22 of Diamond Light Source (UK). This label-free mapping method delivered simultaneous morphological and biochemical information on a subcellular level (i.e. 100 s nanometer or better). Based on specific spectral biomarkers, the main biochemical constituents affected by the drug were identified at distinct locations within the cell´s inner body. Cisplatin was shown to have a noteworthy effect on proteins, mostly within the cytoplasm. A clear drug impact on cellular lipids was also observed. Within current literature on s-SNOM, this nanospectroscopy work represents a first successful application in life sciences providing full fingerprint nano-FTIR spectra across intact human cancer cells.

XRF identification of sharp-force trauma in fresh and dry human bone under varied experimental heat conditions.

Heat-induced fractures can be hard to distinguish from sharp force traumas. This challenge can negatively impact medico-legal analysis. The present study aimed to experimentally assess if X-ray fluorescence (XRF) can be used to detect chemical traces transferred from the blade of a sharp instrument onto both fresh and dry human bones. This was performed by inducing sharp force traumas with five different instruments on 20 fresh and 20 dry human clavicles. All bone samples were probed before and after experimental burning (at 500 °C, 700 °C, 900 °C and 1100 °C). Our results show that XRF is potentially useful for detecting iron traces in fresh human bone, both unburned and burned. However, we were not able to clearly detect iron traces from the blades in bones that have been previously inhumed, since exogenous iron acquired during diagenesis masks the iron traces originating from the blade.

Molecular survey of Piroplasmida, Hepatozoon spp. and Anaplasmataceae in anemic and thrombocytopenic dogs from Uruguay.

Canine tick-borne diseases, such as babesiosis, rangeliosis, hepatozoonosis, anaplasmosis and ehrlichiosis, are of veterinarian relevance, causing mild or severe clinical cases that can lead to the death of the dog. The aim of this study was detecting tick-borne protozoan and rickettsial infections in dogs with anemia and/or thrombocytopenia in Uruguay. A total of 803 domestic dogs were evaluated, and 10% were found positive (detected by PCR) at least for one hemoparasite. Sequence analysis confirmed the presence of four hemoprotozoan species: Rangelia vitalii, Babesia vogeli, Hepatozoon canis and Hepatozoon americanum, and the rickettsial Anaplasma platys. The most detected hemoparasite was R. vitalii, followed by H. canis and A. platys. This is the first report of B. vogeli in Uruguay and the second report of H. americanum in dogs from South America. The results highlight the importance for veterinarians to include hemoparasitic diseases in their differential diagnosis of agents causing anemia and thrombocytopenia.

Vibrational microspectroscopy as a tool to unveil new chemotherapeutic strategies against osteosarcoma.

Over the years, osteosarcoma therapy has had a significative improvement with the use of a multidrug regime strategy, increasing the survival rates from less than 20 % to circa 70 %. Different types of development of new antineoplastic agents are critical to achieve irreversible damage to cancer cells, while preserving the integrity of their healthy counterparts. In the present study, complexes with two and three Pd(II) centres linked by the biogenic polyamines: spermine (Pd2SpmCl4) and spermidine (Pd3Spd2Cl6) were tested against non-malignant (osteoblasts, HOb) and cancer (osteosarcoma, MG-63) human cell lines. Either alone or in combination according to the EURAMOS-1 protocol, they were used versus cisplatin as a drug reference. By evaluating the cytotoxic effects of both therapeutic approaches (single and drug combination) in HOb and MG-63 cell lines, the selective anti-tumoral potential is assessed. To understand the different treatments at a molecular level, Synchrotron Radiation Fourier Transform Infrared and Raman microspectroscopies were applied. Principal component analysis and hierarchical cluster analysis are applied to the vibrational data, revealing the major metabolic changes caused by each drug, which were found to rely on DNA, lipids, and proteins, acting as biomarkers of drug-to-cell impact. The main changes were observed for the B-DNA native conformation to either Z-DNA (higher in the presence of polynuclear complexes) or A-DNA (preferably after cisplatin exposure). Additionally, a higher effect upon variation in proteins content was detected in drug combination when compared to single drug administration proving the efficacy of the EURAMOS-1 protocol with the new drugs tested.

Cervical Squamous Cell Carcinoma Diagnosis by FTIR Microspectroscopy.

Cervical cancer was considered the fourth most common cancer worldwide in 2020. In order to reduce mortality, an early diagnosis of the tumor is required. Currently, this type of cancer occurs mostly in developing countries due to the lack of vaccination and screening against the Human Papillomavirus. Thus, there is an urgent clinical need for new methods aiming at a reliable screening and an early diagnosis of precancerous and cancerous cervical lesions. Vibrational spectroscopy has provided very good results regarding the diagnosis of various tumors, particularly using Fourier transform infrared microspectroscopy, which has proved to be a promising complement to the currently used histopathological methods of cancer diagnosis. This spectroscopic technique was applied to the analysis of cryopreserved human cervical tissue samples, both squamous cell carcinoma (SCC) and non-cancer samples. A dedicated Support Vector Machine classification model was constructed in order to categorize the samples into either normal or malignant and was subsequently validated by cross-validation, with an accuracy higher than 90%.

The effects of exogenous substances on the color of heated bones.

OBJECTIVES: Burned bone coloration has been used for decades to help in the bioanthropological analysis of burned human bones. However, there is a variety of factors that can interfere with the coloration manifested by bones exposed to heat, resulting in colors that differ from the usual black to white gradient. In this study, we evaluated possible causes of unusual coloration changes and hues in burned bone. MATERIALS AND METHODS: For that purpose, defleshed fresh pig (Sus scrofa) ribs as well as fresh and dry human clavicles were burned at four different temperatures (500, 700, 900 and 1100°C) in contact with different materials (CaO, Zn, Fe, Cu, Mn, and polyester cloth). Observable color changes were assessed through naked eye observation and description, Munsell color charts, and reflectance spectrophotometry. Additionally, chemical changes in bone were assessed using Fourier-transform infrared spectroscopy in attenuated total reflectance (FTIR-ATR) and x-ray fluorescence (XRF). RESULTS: Our results showed that some materials did affect usual burned bone coloration (Fe, Mn, Cu, Zn) and correspondent FTIR-ATR and XRF spectra. As for other materials, although no effect on visual bone coloration was observed, they still affected FTIR-ATR and XRF spectra (CaO and cloth). DISCUSSION: This study can contribute to the anthropological analysis of burned human remains, providing some answers to what can cause unusual types of heat-induced colorations.

Design and Evaluation of PROTACs Targeting Acyl Protein Thioesterase 1.

PROTAC linker design remains mostly an empirical task. We employed the PRosettaC computational software in the design of sulfonyl-fluoride-based PROTACs targeting acyl protein thioesterase 1 (APT1). The software efficiently generated ternary complex models from empirically-designed PROTACs and suggested alkyl linkers to be the preferred type of linker to target APT1. Western blotting analysis revealed efficient degradation of APT1 and activity-based protein profiling showed remarkable selectivity of an alkyl linker-based PROTAC amongst serine hydrolases. Collectively, our data suggests that combining PRosettaC and chemoproteomics can effectively assist in triaging PROTACs for synthesis and providing early data on their potency and selectivity.

4-Oxo-ß-Lactams as Novel Inhibitors for Rhomboid Proteases.

Intramembrane serine proteases (rhomboid proteases) are involved in a variety of biological processes and are implicated in several diseases. Here, we report 4-oxo-ß-lactams as a novel scaffold for inhibition of rhomboids. We show that they covalently react with the active site and that the covalent bond is sufficiently stable for detection of the covalent rhomboid-lactam complex. 4-Oxo-ß-lactams may therefore find future use as both inhibitors and activity-based probes for rhomboid proteases.

Spectrochemical analysis of seasonal and sexual variation of antioxidants in Corema album (L.) D. Don leaf extracts.

Bioactive phytoconstituents have been increasingly investigated for their potential human health benefits. Corema album (L.) D. Don, an Ericaceae, reportedly has antioxidant, antimicrobial and anticancer properties. Aiming at enhancing its nutraceutical potential, we performed a spectrochemical analysis of hydroethanolic extracts from C. album leaves. We report on changes in the antioxidant activity of the extracts, as well as in the accumulation of key phytoconstituents (namely phenolic compounds), in female and male samples, throughout three harvesting seasons (February, July, and October). For each extract, the antioxidant activity was assessed by different spectrophotometric methods. Simultaneously, attenuated total reflectance Fourier transform mid-infrared spectroscopy (FTIR-ATR), and high-performance liquid chromatography - electrospray ionisation - quadrupole time-of-flight mass spectrometry (HPLC-ESI-Q-TOF-MS), were used to identify and monitor variations in the composition of phenolic compounds in the extracts. The main compounds identified were epicatechin, laricitrin-O-hexoside isomers, and myricetin-O-hexoside isomers. Significant differences were found in the composition and relative abundance of the compounds of interest, according to sex and season. Overall, a trend was observed whereby phenolic content and antioxidant activities were higher in males and increased between the earlier and the latest harvests. Based on these results, we may conclude that late summer or early autumn harvests are preferable when aiming at the highest yearly content of bioactive compounds. Additionally, it should be considered that extracts from male individuals typically display higher antioxidant activities. Ultimately, our understanding of C. album in the context of nutraceutical applications is benefited from the quantitative and qualitative portrait provided here, thus promoting its relevance as a source of bioactive compounds.

A Non-Conventional Platinum Drug against a Non-Small Cell Lung Cancer Line.

A dinuclear Pt(II) complex with putrescine as bridging polyamine ligand ([Pt2Put2(NH3)4]Cl4) was synthesized and assessed as to its potential anticancer activity against a human non-small cell lung cancer line (A549), as well as towards non-cancer cells (BEAS-2B). This effect was evaluated through in vitro cytotoxicity assays (MTT and SRB) coupled to microFTIR and microRaman spectroscopies, the former delivering information on growth-inhibiting and cytotoxic abilities while the latter provided very specific information on the metabolic impact of the metal agent (at the sub-cellular level). Regarding cancer cells, a major impact of [Pt2Put2(NH3)4]Cl4 was evidenced on cellular proteins and lipids, as compared to DNA, particularly via the Amide I and Amide II signals. The effect of the chelate on non-malignant cells was lower than on malignant ones, evidencing a promising low toxicity towards healthy cells.

Antioxidant Potential of Tamarillo Fruits-Chemical and Infrared Spectroscopy Analysis.

Native to South America, tamarillo (Solanum betaceum Cav.) is a small tree cultivated as a fruit crop in several regions of the world. Known for its sweet and sour taste, tamarillo fruits are very nutritious due to the presence of health-beneficial components such as fiber, vitamins, and antioxidants. Despite its nutritional value, tamarillo remains poorly known in global markets. The present work aims to study the antioxidant activity of four genotypes of tamarillo. Several chemical assays were performed to assess the antioxidant components and antioxidant activity of aqueous ethanolic extracts from each genotype. Overall, the Mealhada genotype (a red cultivar) showed the most interesting results, displaying the highest amount of total phenolic, flavonoids, and anthocyanin contents, as well as higher antioxidant activity. To evaluate the composition of the extract, Fourier-transform infrared spectroscopy (FTIR) was used to characterize important components in aqueous ethanolic extracts of the fruits, having revealed the presence of high amounts of phenols (the main compounds responsible for antioxidant activity), as well as triterpenoids and polysaccharides. The present results highlight the potential nutraceutical importance of tamarillo fruits.

Evaluation of the Cytotoxic Effect of Pd2Spm against Prostate Cancer through Vibrational Microspectroscopies.

Regarding the development of new antineoplastic agents, with a view to assess the selective antitumoral potential which aims at causing irreversible damage to cancer cells while preserving the integrity of their healthy counterparts, it is essential to evaluate the cytotoxic effects in both healthy and malignant human cell lines. In this study, a complex with two Pd(II) centers linked by the biogenic polyamine spermine (Pd2Spm) was tested on healthy (PNT-2) and cancer (LNCaP and PC-3) prostate human cell lines, using cisplatin as a reference. To understand the mechanisms of action of both cisplatin and Pd2Spm at a molecular level, Fourier Transform Infrared (FTIR) and Raman microspectroscopies were used. Principal component analysis was applied to the vibrational data, revealing the major metabolic changes caused by each drug, which were found to rely on DNA, lipids, and proteins, acting as biomarkers of drug impact. The main changes were observed between the B-DNA native conformation and either Z-DNA or A-DNA, with a higher effect on lipids having been detected in the presence of cisplatin as compared to Pd2Spm. In turn, the Pd-agent showed a more significant impact on proteins.

Burned and buried: A vibrational spectroscopy analysis of burial-related diagenetic changes of heat-altered human bones.

OBJECTIVES: The analysis of burned human remains can be very challenging due to heat-induced alterations. Occasionally, human bones present these coupled with diagenetic changes, offering even more of a challenge, since there is a lack of studies regarding interactions between both taphonomic phenomena. With this study, we aimed to assess and document the effects of inhumation on the chemical composition of both unburned and burned human skeletal remains. MATERIALS AND METHODS: We buried, for 5 years, four groups of human bone samples comprising unburned bones and bones experimentally burned at 500, 900, and 1050 °C. Periodic exhumations were carried out to collect bone samples to be analyzed through Fourier transform infrared spectroscopy in attenuated total reflectance mode, in order to calculate four chemical indexes: (1) crystallinity index (CI); (2) type B carbonates to phosphate index (BPI); (3) total carbonates (A + B) to carbonate B ratio (C/C); and (4) OH to phosphate ratio (OH/P). RESULTS: After inhumation, CI and C/C of unburned bones and bones burned at 500 °C, and BPI of bones burned at 1050 °C did not vary significantly. However, the remaining indexes showed both relevant increments and reductions throughout observations, depending on burning temperature and index. DISCUSSION: Our results suggest that diagenesis can have an effect in bone's molecular composition. However, these effects do not seem to significantly affect the conclusions that can be taken from the analysis of infrared bone spectra, at least in the case of inhumations with a duration of 5 years or less.

In-Situ Anaerobic Heating of Human Bones Probed by Neutron Diffraction.

The first neutron diffraction study of in-situ anaerobic burning of human bones is reported, aiming at an interpretation of heat-induced changes in bone, which were previously detected by vibrational spectroscopy, including inelastic neutron scattering techniques. Structural and crystallinity variations were monitored in samples of the human femur and tibia, as well as a reference hydroxyapatite, upon heating under anaerobic conditions. Information on the structural reorganization of the bone matrix as a function of temperature, from room temperature to 1000 °C, was achieved. Noticeable crystallographic and domain size variations, together with O-H bond lengths and background variations, were detected. Above 700 °C, the inorganic bone matrix became highly symmetric, devoid of carbonates and organic constituents, while for the lower temperature range (<700 °C), a considerably lower crystallinity was observed. The present pilot study is expected to contribute to a better understanding of the heat-prompted changes in bone, which can be taken as biomarkers of the burning temperature. This information is paramount for bone analysis in forensic science as well as in archeology and may also have useful applications in other biomaterial studies.

The Role of Hidden Conformers in Determination of Conformational Preferences of Mefenamic Acid by NOESY Spectroscopy.

Mefenamic acid has been used as a non-steroidal anti-inflammatory drug for a long time. However, its practical use is quite limited due to a number of side effects on the intestinal organs. Conformational polymorphism provides mefenamic acid with unique properties regarding possible modifications obtained during the micronization process, which can improve pharmacokinetics and minimize side effects. Micronization can be performed by decompression of supercritical fluids; methods such as rapid expansion of the supercritical solution have proven their efficiency. However, this group of methods is poorly applicable for compounds with low solubility, and the modification of the method using a pharmaceutically suitable co-solvent may be useful. In our case, addition of only 2 mol% dimethyl sulfoxide increased the solubility remarkably. Information on the conformational state may be critically important for carrying out micronization. In this work, structural analysis and estimate of conformational preferences of mefenamic acid in dimethyl sulfoxide-d6 (at 25 °C and 0.1 MPa) and in a mixed solvent supercritical carbon dioxide + dimethyl sulfoxide-d6 (45 °C, 9 MPa) were performed based on nuclear Overhauser effect spectroscopy. Results show changes in the conformation fractions depending on the medium used. The importance of allowing for hidden conformers in estimating the conformational state was demonstrated in the analysis. Obtained results may be useful for improving micronization parameters.

Chemical trace XRF analysis to detect sharp force trauma in fresh and burned bone.

Forensic anthropologists may not always be able to differentiate heat-induced fractures from fractures with other aetiologies, namely sharp force traumas, with clear nefarious impact on medico-legal conclusions. The objective of this study was to experimentally investigate if blade chemical traces are transferred to defleshed bone tissue and if they remain there after a burning event. This was accomplished by prompting sharp force traumas in 20 macerated fresh pig ribs with five different instruments, namely a stainless steel knife, an artisanal knife and a ceramic kitchen knife, a small axe and a large axe. Another pig rib was used as control, not being subjected to any trauma. All instruments were probed by X-ray fluorescence (XRF) to establish the composition of each blade. Bone samples, both pre-burned and post-burned (at 500 °C, 700 °C, 900 °C and 1100 °C), were then probed by XRF. All sharp force instruments left detectable chemical traces on pre-burned bone, although not in all samples. Furthermore, traces were still detected after experimental burning in most cases. Potentially, XRF can provide relevant information about the aetiology of fractures in burned and unburned bones, although the effect of soft tissues and diagenesis must still be investigated.

Selective Inhibition of Bruton's Tyrosine Kinase by a Designed Covalent Ligand Leads to Potent Therapeutic Efficacy in Blood Cancers Relative to Clinically Used Inhibitors.

Bruton's tyrosine kinase (BTK) is a member of the TEC-family kinases and crucial for the proliferation and differentiation of B-cells. We evaluated the therapeutic potential of a covalent inhibitor (JS25) with nanomolar potency against BTK and with a more desirable selectivity and inhibitory profile compared to the FDA-approved BTK inhibitors ibrutinib and acalabrutinib. Structural prediction of the BTK/JS25 complex revealed sequestration of Tyr551 that leads to BTK's inactivation. JS25 also inhibited the proliferation of myeloid and lymphoid B-cell cancer cell lines. Its therapeutic potential was further tested against ibrutinib in preclinical models of B-cell cancers. JS25 treatment induced a more pronounced cell death in a murine xenograft model of Burkitt's lymphoma, causing a 30-40% reduction of the subcutaneous tumor and an overall reduction in the percentage of metastasis and secondary tumor formation. In a patient model of diffuse large B-cell lymphoma, the drug response of JS25 was higher than that of ibrutinib, leading to a 64% "on-target" efficacy. Finally, in zebrafish patient-derived xenografts of chronic lymphocytic leukemia, JS25 was faster and more effective in decreasing tumor burden, producing superior therapeutic effects compared to ibrutinib. We expect JS25 to become therapeutically relevant as a BTK inhibitor and to find applications in the treatment of hematological cancers and other pathologies with unmet clinical treatment.

Breast cancer or surrounding normal tissue? A successful discrimination by FTIR or Raman microspectroscopy.

Breast cancer is a type of cancer with the highest incidence worldwide in 2021, with early diagnosis and rapid treatment intervention being the reasons for the decreasing mortality rate associated with the disease. The major challenge faced by clinicians and pathologists is the lack of accuracy in the histopathological analysis of biopsy or resection samples, leading to classification misdiagnosis and compromising the prognosis of patients. Spectral histopathology has provided great advances regarding cancer diagnosis, especially through the use of FTIR spectroscopy, proving to be a valuable complement to histopathological analyses. In this study unstained formalin-fixed paraffin embedded breast cancer tissue samples, collected from patients undergoing surgery and mounted on glass slides, were probed through FTIR and Raman microspectrocopy. Two classification models were constructed using the AdaBoost algorithm, both achieving >90% accuracy and successfully discriminating invasive breast carcinoma from surrounding normal tissue. Chemical maps from the interfaces of invasive breast carcinoma-surrounding normal tissue were also generated. This study showed the potential of spectral histopathology, in particular FTIR, for daily use in pathology laboratories, introducing few disruptions to the routine workflow while increasing the sensitivity, specificity and accuracy of the diagnoses.

Valorisation Potential of Invasive Acacia dealbata, A. longifolia and A. melanoxylon from Land Clearings.

Acacia spp. are invasive in Southern Europe, and their high propagation rates produce excessive biomass, exacerbating wildfire risk. However, lignocellulosic biomass from Acacia spp. may be utilised for diverse biorefinery applications. In this study, attenuated total reflectance Fourier transform infrared spectroscopy (FTIR-ATR), high-performance anion-exchange chromatography pulsed amperometric detection (HPAEC-PAD) and lignin content determinations were used for a comparative compositional characterisation of A. dealbata, A. longifolia and A. melanoxylon. Additionally, biomass was treated with three white-rot fungi species (Ganoderma lucidum, Pleurotus ostreatus and Trametes versicolor), which preferentially degrade lignin. Our results showed that the pre-treatments do not significantly alter neutral sugar composition while reducing lignin content. Sugar release from enzymatic saccharification was enhanced, in some cases possibly due to a synergy between white-rot fungi and mild alkali pretreatments. For example, in A. dealbata stems treated with alkali and P. ostreatus, saccharification yield was 702.3 nmol mg-1, which is higher than the samples treated only with alkali (608.1 nmol mg-1), and 2.9-fold higher than the non-pretreated controls (243.9 nmol mg-1). By characterising biomass and pretreatments, generated data creates value for unused biomass resources, contributing to the implementation of sustainable biorefining systems. In due course, the generated value will lead to economic incentives for landowners to cut back invasive Acacia spp. more frequently, thus reducing excess biomass, which exacerbates wildfire risk.