Synthesis, Characterization, and Cytotoxicity Evaluation of Novel Water-Soluble Cationic Platinum(II) Organometallic Complexes with Phenanthroline and Imidazolic Ligands.

Platinum-based chemotherapeutic agents are widely used in the treatment of cancer. However, their effectiveness is limited by severe adverse reactions, drug resistance, and poor water solubility. This study focuses on the synthesis and characterization of new water-soluble cationic monofunctional platinum(II) complexes starting from the [PtCl(η1-C2H4OEt)(phen)] (1, phen=1,10-phenanthroline) precursor, specifically [Pt(NH3)(η1-C2H4OEt)(phen)]Cl (2), [Pt(1-hexyl-1H-imidazole)(η1-C2H4OEt)(phen)]Cl (3), and [Pt(1-hexyl-1H-benzo[d]imidazole)(η1-C2H4OEt)(phen)]Cl (4), which deviate from traditional requirements for antitumor activity. These complexes were evaluated for their cytotoxic effects in comparison to cisplatin, using immortalized cervical adenocarcinoma cells (HeLa), human renal carcinoma cells (Caki-1), and normal human renal cells (HK-2). While complex 2 showed minimal effects on the cell lines, complexes 3 and 4 demonstrated higher cytotoxicity than cisplatin. Notably, complex 4 displayed the highest cytotoxicity in both cancer and normal cell lines. However, complex 3 exhibited the highest selectivity for renal tumor cells (Caki-1) among the tested complexes, compared to healthy cells (HK-2). This resulted in a significantly higher selectivity than that of cisplatin and complex 4. Therefore, complex 3 shows potential as a leading candidate for the development of a new generation of platinum-based anticancer drugs, utilizing biocompatible imidazole ligands while demonstrating promising anticancer properties.

Incorporation of N7-Platinated Guanines into Thermus Aquaticus (Taq) DNA Polymerase: Atomistic Insights from Molecular Dynamics Simulations.

In this work, we elucidated some key aspects of the mechanism of action of the cisplatin anticancer drug, cis-[Pt(NH3)2Cl2], involving direct interactions with free nucleotides. A comprehensive in silico molecular modeling analysis was conducted to compare the interactions of Thermus aquaticus (Taq) DNA polymerase with three distinct N7-platinated deoxyguanosine triphosphates: [Pt(dien)(N7-dGTP)] (1), cis-[Pt(NH3)2Cl(N7-dGTP)] (2), and cis-[Pt(NH3)2(H2O)(N7-dGTP)] (3) {dien = diethylenetriamine; dGTP = 5'-(2'-deoxy)-guanosine-triphosphate}, using canonical dGTP as a reference, in the presence of DNA. The goal was to elucidate the binding site interactions between Taq DNA polymerase and the tested nucleotide derivatives, providing valuable atomistic insights. Unbiased molecular dynamics simulations (200 ns for each complex) with explicit water molecules were performed on the four ternary complexes, yielding significant findings that contribute to a better understanding of experimental results. The molecular modeling highlighted the crucial role of a specific α-helix (O-helix) within the fingers subdomain, which facilitates the proper geometry for functional contacts between the incoming nucleotide and the DNA template needed for incorporation into the polymerase. The analysis revealed that complex 1 exhibits a much lower affinity for Taq DNA polymerase than complexes 2-3. The affinities of cisplatin metabolites 2-3 for Taq DNA polymerase were found to be quite similar to those of natural dGTP, resulting in a lower incorporation rate for complex 1 compared to complexes 2-3. These findings could have significant implications for the cisplatin mechanism of action, as the high intracellular availability of free nucleobases might promote the competitive incorporation of platinated nucleotides over direct cisplatin attachment to DNA. The study's insights into the incorporation of platinated nucleotides into the Taq DNA polymerase active site suggest that the role of platinated nucleotides in the cisplatin mechanism of action may have been previously underestimated.

Wireframe DNA Origami for the Cellular Delivery of Platinum(II)-Based Drugs.

The DNA origami method has revolutionized the field of DNA nanotechnology since its introduction. These nanostructures, with their customizable shape and size, addressability, nontoxicity, and capacity to carry bioactive molecules, are promising vehicles for therapeutic delivery. Different approaches have been developed for manipulating and folding DNA origami, resulting in compact lattice-based and wireframe designs. Platinum-based complexes, such as cisplatin and phenanthriplatin, have gained attention for their potential in cancer and antiviral treatments. Phenanthriplatin, in particular, has shown significant antitumor properties by binding to DNA at a single site and inhibiting transcription. The present work aims to study wireframe DNA origami nanostructures as possible carriers for platinum compounds in cancer therapy, employing both cisplatin and phenanthriplatin as model compounds. This research explores the assembly, platinum loading capacity, stability, and modulation of cytotoxicity in cancer cell lines. The findings indicate that nanomolar quantities of the ball-like origami nanostructure, obtained in the presence of phenanthriplatin and therefore loaded with that specific drug, reduced cell viability in MCF-7 (cisplatin-resistant breast adenocarcinoma cell line) to 33%, while being ineffective on the other tested cancer cell lines. The overall results provide valuable insights into using wireframe DNA origami as a highly stable possible carrier of Pt species for very long time-release purposes.

Compatibility of Nucleobases Containing Pt(II) Complexes with Red Blood Cells for Possible Drug Delivery Applications.

The therapeutic advantages of some platinum complexes as major anticancer chemotherapeutic agents and of nucleoside analogue-based compounds as essential antiviral/antitumor drugs are widely recognized. Red blood cells (RBCs) offer a potential new strategy for the targeted release of therapeutic agents due to their biocompatibility, which can protect loaded drugs from inactivation in the blood, thus improving biodistribution. In this study, we evaluated the feasibility of loading model nucleobase-containing Pt(II) complexes into human RBCs that were highly stabilized by four N-donors and susceptible to further modification for possible antitumor/antiviral applications. Specifically, platinum-based nucleoside derivatives [PtII(dien)(N7-Guo)]2+, [PtII(dien)(N7-dGuo)]2+, and [PtII(dien)(N7-dGTP)] (dien = diethylenetriamine; Guo = guanosine; dGuo = 2'-deoxy-guanosine; dGTP = 5'-(2'-deoxy)-guanosine-triphosphate) were investigated. These Pt(II) complexes were demonstrated to be stable species suitable for incorporation into RBCs. This result opens avenues for the possible incorporation of other metalated nucleobases analogues, with potential antitumor and/or antiviral activity, into RBCs.

Management and 1-year outcomes of anastomotic leakage after elective colorectal surgery.

PURPOSE: To analyze different types of management and one-year outcomes of anastomotic leakage (AL) after elective colorectal resection. METHODS: All patients with anastomotic leakage after elective colorectal surgery with anastomosis (76/1,546; 4.9%), with the exclusion of cases with proximal diverting stoma, were followed-up for at least one year. Primary endpoints were as follows: composite outcome of one-year mortality and/or unplanned intensive care unit (ICU) admission and additional morbidity rates. Secondary endpoints were as follows: length of stay (LOS), one-year persistent stoma rate, and rate of return to intended oncologic therapy (RIOT). RESULTS: One-year mortality rate was 10.5% and unplanned ICU admission rate was 30.3%. Risk factors of the composite outcome included age (aOR = 1.08 per 1-year increase, p = 0.002) and anastomotic breakdown with end stoma at reoperation (aOR = 2.77, p = 0.007). Additional morbidity rate was 52.6%: risk factors included open versus laparoscopic reoperation (aOR = 4.38, p = 0.03) and ICU admission (aOR = 3.63, p = 0.05). Median (IQR) overall LOS was 20 days (14-26), higher in the subgroup of patients reoperated without stoma. At 1 year, a stoma persisted in 32.0% of patients, higher in the open (41.2%) versus laparoscopic (12.5%) reoperation group (p = 0.04). Only 4 out of 18 patients (22.2%) were able to RIOT. CONCLUSION: Mortality and/or unplanned ICU admission rates after AL are influenced by increasing age and by anastomotic breakdown at reoperation; additional morbidity rates are influenced by unplanned ICU admission and by laparoscopic approach to reoperation, the latter also reducing permanent stoma and failure to RIOT rates. TRIAL REGISTRATION: ClinicalTrials.gov # NCT03560180.

NMR-Based Metabolomics in Metal-Based Drug Research.

Thanks to recent advances in analytical technologies and statistical capabilities, the application field of metabolomics has increased significantly. Currently, this approach is used to investigate biological substrates looking for metabolic profile alterations, diseases markers, and drug effects. In particular, NMR spectroscopy has shown great potential as a detection technique, mainly for the ability to detect multiple (10s to 100s) metabolites at once without separation. Only in recent years has the NMR-based metabolomic approach been extended to investigate the cell metabolic alterations induced by metal-based antitumor drug administration. As expected, these studies are mainly focused on platinum complexes, but some palladium and ruthenium compounds are also under investigation. The use of a metabolomics approach was very effective in assessing tumor response to drugs and providing insights into the mechanism of action and resistance. Therefore, metabolomics may open new perspectives into the development of metal-based drugs. In particular, it has been shown that NMR-based, in vitro metabolomics is a powerful tool for detecting variations of the cell metabolites induced by the metal drug exposure, thus offering also the possibility of identifying specific markers for in vivo monitoring of tumor responsiveness to anticancer treatments.

Response of Cisplatin Resistant Skov-3 Cells to [Pt(O,O'-Acac)(γ-Acac)(DMS)] Treatment Revealed by a Metabolomic ¹H-NMR Study.

The novel [Pt(O,O'-acac)(γ-acac)(DMS)], Ptac2S, Pt(II) complex has recently gained increasing attention as a potential anticancer agent for its pharmacological activity shown in different tumor cell lines, studied both in vitro and in vivo. The mechanism of action of Ptac2S, operating on non-genomic targets, is known to be very different from that of cis-[PtCl2(NH3)2], cisplatin, targeting nucleic acids. In this work, we evaluated the cytotoxicity of Ptac2S on the cisplatin resistant Epithelial Ovarian Carcinoma (EOC), SKOV-3 cells, by the MTT assay. A ¹H-NMR metabolomic approach coupled with multivariate statistical analysis was used for the first time for Ptac2S to figure out the biological mechanisms of action of the complex. The metabolic variations of intracellular metabolites and the composition of the corresponding extracellular culture media were compared to those of cisplatin (cells were treated at the IC50 doses of both drugs). The reported comparative metabolomic analysis revealed a very different metabolic profile between Ptac2S and cisplatin treated samples, thus confirming the different mechanism of action of Ptac2S also in the Epithelial Ovarian Carcinoma (EOC), SKOV-3 cells line. In particular, higher levels of pyruvate were observed in Ptac2S treated, with respect to cisplatin treated, cells (in both aqueous and culture media). In addition, a very different lipid expression resulted after the exposure to the two drugs (Ptac2S and cisplatin). These results suggest a possible explanation for the Ptac2S ability to circumvent cisplatin resistance in SKOV-3 cells.

Pauling Electronegativity On/Off Effects Assessed by 13 C and 29 Si†NMR Spectroscopic Analysis.

In carbon and silicon tetrahalide compounds, the experimental 13 C and 29 Si NMR chemical-shift values are known to increase or decrease on increasing the overall sum of the ionic radii of the bonded halides Σ(rh ) (normal and inverse halogen dependence (NHD and IHD, respectively)). Herein, we extrapolate the main factors responsible for such NMR chemical shifts. Intriguingly, we found a characteristic value for the overall sum of the Pauling electronegativities of the bonded halides Σ(χh ), which works as a triggering factor to determine the transition from the NHD to IHD. Below this Σ(χh ) value, the chemical shift of the central atom was strictly related to only the Σ(rh ) value, thus producing a NHD trend. Conversely, above this value, the chemical shift of the central atom was dependent on both the Σ(rh ) and Σ(χh ) values, thus producing a IHD trend. A simple model, in which the effect of the Σ(χh ) value on 13 C and 29 Si NMR chemical shifts is related to an apparent increase in the Σ(rh ) value, is deduced.

Gastrointestinal stromal tumors of the stomach: the role of laparoscopic resection. Single-centre experience of 38 cases.

INTRODUCTION: Laparoscopic resection is considered the gold standard of treatment only for small gastric gastrointestinal stromal tumor (GIST). MATERIALS AND METHODS: Between January 2004 and September 2012, 38 consecutive gastric GISTs were operated on by laparoscopic approach, without conversions. Thirty-five cases were primary GISTs and three were bleeding GISTs with hepatic metastases non-responding to conservative therapy treated by emergency surgery. RESULTS: Median tumor size was 3.63 cm (1.8-17 cm). In two cases tumor size was <2 cm, between 2 and 5 cm in 26 cases, between 5 and 10 cm in eight cases, and >10 cm in two cases. In two cases, localization was in the cardia, fundus in ten cases, lesser curve in 11 cases, greater curve in 12 cases, and antrum in three cases. We performed 24 wedge resections, eight transgastric resections and six antrectomies. An Endo-GIA™ was used in 25 cases, and a manual laparoscopic reconstruction with extramucosal suture was performed in 13 cases. No postoperative mortality and morbidity was observed. The routine use of laparoscopy allowed us to perform resections in 100 % of cases, even in those where preoperative imaging suggested an open approach according to the current guidelines. CONCLUSIONS: The use of a pre-resection endobag avoids spillage and seeding, thus increasing the possibility of resection. In conclusion, we consider the laparoscopic approach as mandatory in all cases, always considering the possibility of converting to the open technique when necessary.

Mechanical bowel preparation in elective colorectal surgery: a propensity score-matched analysis of the Italian colorectal anastomotic leakage (iCral) study group prospective cohorts.

Retrospective evaluation of the effects of mechanical bowel preparation (MBP) on data derived from two prospective open-label observational multicenter studies in Italy regarding elective colorectal surgery. MBP for elective colorectal surgery remains a controversial issue with contrasting recommendations in current guidelines. The Italian ColoRectal Anastomotic Leakage (iCral) study group, therefore, decided to estimate the effects of no MBP (treatment variable) versus MBP for elective colorectal surgery. A total of 8359 patients who underwent colorectal resection with anastomosis were enrolled in two consecutive prospective studies in 78 surgical centers in Italy from January 2019 to September 2021. A retrospective PSMA was performed on 5455 (65.3%) cases after the application of explicit exclusion criteria to eliminate confounders. The primary endpoints were anastomotic leakage (AL) and surgical site infections (SSI) rates; the secondary endpoints included SSI subgroups, overall and major morbidity, reoperation, and mortality rates. Overall length of postoperative hospital stay (LOS) was also considered. Two well-balanced groups of 1125 patients each were generated: group A (No MBP, true population of interest), and group B (MBP, control population), performing a PSMA considering 21 covariates. Group A vs. group B resulted significantly associated with a lower risk of AL [42 (3.5%) vs. 73 (6.0%) events; OR 0.57; 95% CI 0.38-0.84; p = 0.005]. No difference was recorded between the two groups for SSI [73 (6.0%) vs. 85 (7.0%) events; OR 0.88; 95% CI 0.63-1.22; p = 0.441]. Regarding the secondary endpoints, no MBP resulted significantly associated with a lower risk of reoperation and LOS > 6 days. This study confirms that no MBP before elective colorectal surgery is significantly associated with a lower risk of AL, reoperation rate, and LOS < 6 days when compared with MBP.

Platinum-Nucleos(t)ide Compounds as Possible Antimetabolites for Antitumor/Antiviral Therapy: Properties and Perspectives.

Nucleoside analogues (NAs) are a family of compounds which include a variety of purine and pyrimidine derivatives, widely used as anticancer and antiviral agents. For their ability to compete with physiological nucleosides, NAs act as antimetabolites exerting their activity by interfering with the synthesis of nucleic acids. Much progress in the comprehension of their molecular mechanisms has been made, including providing new strategies for potentiating anticancer/antiviral activity. Among these strategies, new platinum-NAs showing a good potential to improve the therapeutic indices of NAs have been synthesized and studied. This short review aims to describe the properties and future perspectives of platinum-NAs, proposing these complexes as a new class of antimetabolites.

Blood Transfusions and Adverse Events after Colorectal Surgery: A Propensity-Score-Matched Analysis of a Hen-Egg Issue.

Blood transfusions are considered a risk factor for adverse outcomes after colorectal surgery. However, it is still unclear if they are the cause (the hen) or the consequence (the egg) of adverse events. A prospective database of 4529 colorectal resections gathered over a 12-month period in 76 Italian surgical units (the iCral3 study), reporting patient-, disease-, and procedure-related variables, together with 60-day adverse events, was retrospectively analyzed identifying a subgroup of 304 cases (6.7%) that received intra- and/or postoperative blood transfusions (IPBTs). The endpoints considered were overall and major morbidity (OM and MM, respectively), anastomotic leakage (AL), and mortality (M) rates. After the exclusion of 336 patients who underwent neo-adjuvant treatments, 4193 (92.6%) cases were analyzed through a 1:1 propensity score matching model including 22 covariates. Two well-balanced groups of 275 patients each were obtained: group A, presence of IPBT, and group B, absence of IPBT. Group A vs. group B showed a significantly higher risk of overall morbidity (154 (56%) vs. 84 (31%) events; OR 3.07; 95%CI 2.13-4.43; p = 0.001), major morbidity (59 (21%) vs. 13 (4.7%) events; OR 6.06; 95%CI 3.17-11.6; p = 0.001), and anastomotic leakage (31 (11.3%) vs. 8 (2.9%) events; OR 4.72; 95%CI 2.09-10.66; p = 0.0002). No significant difference was recorded between the two groups concerning the risk of mortality. The original subpopulation of 304 patients that received IPBT was further analyzed considering three variables: appropriateness of BT according to liberal transfusion thresholds, BT following any hemorrhagic and/or major adverse event, and major adverse event following BT without any previous hemorrhagic adverse event. Inappropriate BT was administered in more than a quarter of cases, without any significant influence on any endpoint. The majority of BT was administered after a hemorrhagic or a major adverse event, with significantly higher rates of MM and AL. Finally, a major adverse event followed BT in a minority (4.3%) of cases, with significantly higher MM, AL, and M rates. In conclusion, although the majority of IPBT was administered with the consequence of hemorrhage and/or major adverse events (the egg), after adjustment accounting for 22 covariates, IPBT still resulted in a definite source of a higher risk of major morbidity and anastomotic leakage rates after colorectal surgery (the hen), calling urgent attention to the implementation of patient blood management programs.

Evaluation of the Antitumor Effects of Platinum-Based [Pt(η1-C2H4-OR)(DMSO)(phen)]+ (R = Me, Et) Cationic Organometallic Complexes on Chemoresistant Pancreatic Cancer Cell Lines.

Pancreatic cancer is one of the most lethal malignancies with an increasing incidence and a high mortality rate, due to its rapid progression, invasiveness, and resistance to anticancer therapies. In this work, we evaluated the antiproliferative and antimigratory activities of the two organometallic compounds, [Pt(η1-C2H4-OMe)(DMSO)(phen)]Cl (1) and [Pt(η1-C2H4-OEt)(DMSO)(phen)]Cl (2), on three human pancreatic ductal adenocarcinoma cell lines with different sensitivity to cisplatin (Mia PaCa-2, PANC-1, and YAPC). The two cationic analogues showed superimposable antiproliferative effects on the tested cells, without significant differences depending on alkyl chain length (Me or Et). On the other hand, they demonstrated to be more effective than cisplatin, especially on YAPC cancer cells. For the interesting cytotoxic activity observed on YAPC, further biological assays were performed, on this cancer cell line, to evaluate the apoptotic and antimetastatic properties of the considered platinum compounds (1 and 2). The cytotoxicity of 1 and 2 compounds appeared to be related to their intracellular accumulation, which was much faster than that of cisplatin. Both 1 and 2 compounds significantly induced apoptosis and cell cycle arrest, with a high accumulation of sub-G1 phase cells, compared to cisplatin. Moreover, phenanthroline-containing complexes caused a rapid loss of mitochondria membrane potential, ΔΨM, if compared to cisplatin, probably due to their cationic and lipophilic properties. On 3D tumor spheroids, 1 and 2 significantly reduced migrated area more than cisplatin, confirming an antimetastatic ability.

Antitumor and antimigration effects of a new Pt compound on neuroblastoma cells.

Among the new Pt complexes with anticancer properties, phenanthroline derivatives have aroused great interest due to their different mode of action compared to cisplatin. We previously examined cytotoxic effects of a new Pt(II)-complex containing 1,10-phenantroline (phen), [Pt(η1-C2H4OMe)(DMSO)(phen)]Cl, in a panel of eight human cancer cell lines, and showed that it exerted the greatest cytotoxic effect in the neuroblastoma SH-SY5Y cell line. In this study, the antiproliferative and antimetastatic potential of [Pt(η1-C2H4OMe)(DMSO)(phen)]+ (in short Pt-EtOMeSOphen) was investigated in neuroblastoma SH-SY5Y, SK-N-SH and SK-N-BE(2) cells. Pt-EtOMeSOphen provoked the early signs of apoptosis induction (cleavage of PARP and activation of caspases-9 and -7); it also increased the level of proapoptotic Bax protein whereas it decreased the level of the antiapoptotic Bcl-2 protein. The effects of Pt-EtOMeSOphen on migration and invasion processes were also evaluated. A decrease of cell migration/invasion by Pt-EtOMeSOphen was observed through 2D and 3D in vitro assays. Pt-EtOMeSOphen was found to exert its actions by decreasing MMP-9 and MMP-2 expressions and activities. Pt-EtOMeSOphen provoked the phosphorylation of both ERK1/2 and p38 MAPKs. All the effects of Pt-EtOMeSOphen on SH-SY5Y cell vitality, migration and metalloproteases activities described here were due to the activation of p38 MAPK since pharmacological p38 MAPK inhibition or small interfering RNAs to p38 MAPK mRNA blocked such effects. Results suggest that Pt-EtOMeSOphen inhibits neuroblastoma cancer cells survival, motility, and invasion. This could lead to the reduction of neuroblastoma metastatic potential.

A NMR-Based Metabolomic Approach to Investigate the Antitumor Effects of the Novel [Pt(η 1-C2H4OMe)(DMSO)(phen)]+ (phen = 1,10-Phenanthroline) Compound on Neuroblastoma Cancer Cells.

NMR-based metabolomics is a very effective tool to assess the tumor response to drugs by providing insights for their mode of action. Recently, a novel Pt(II) complex, [Pt(ƞ1-C2H4OMe)(DMSO)(phen)]+ (phen = 1,10-phenanthroline), Pt-EtOMeSOphen, was synthesized and studied for its antitumor activity against eight human cancer cell lines. Pt-EtOMeSOphen showed higher cytotoxic effects than cisplatin in most of the cancer cell lines and in particular against the neuroblastoma cell line (SH-SY5Y). In this study, the mechanism of action of Pt-EtOMeSOphen on SH-SY5Y cells was investigated using 1H NMR-based metabolomics and compared with cisplatin. The observed time response of SH-SY5Y cells under treatment revealed a faster action of Pt-EtOMeSOphen compared with cisplatin, with a response already observed after six hours of exposure, suggesting a cytosolic target. NMR-based metabolomics demonstrated a peculiar alteration of the glutathione metabolism pathway and the diacylglycerol expression.

First evidence for N7-Platinated Guanosine derivatives cell uptake mediated by plasma membrane transport processes.

Nucleos(t)ide analogues (NA) belong to a family of compounds widely used in anticancer/antiviral treatments. They generally exhibit a cell toxicity limited by cellular uptake levels and the resulting nucleos(t)ides metabolism modifications, interfering with the cell machinery for nucleic acids synthesis. We previously synthesized purine nucleos(t)ide analogues N7-coordinated to a platinum centre with unaltered sugar moieties of the type: [Pt(dien)(N7-dGuo)]2+ (1; dien = diethylenetriamine; dGuo = 2'-deoxy-guanosine), [Pt(dien)(N7-dGMP)] (2; dGMP = 5'-(2'-deoxy)-guanosine monophosphate), and [Pt(dien)(N7-dGTP)]2- (3; dGTP = 5'-(2'-deoxy)-guanosine triphosphate), where the indicated electric charge is calculated at physiological pH (7.4). In this work, we specifically investigated the uptake of these complexes (1-3) at the plasma membrane level. Specific experiments on HeLa cervical cancer cells indicated a relevant cellular uptake of the model platinated deoxynucleos(t)ide 1 and 3 while complex 2 appeared unable to cross the cell plasma membrane. Obtained data buttress an uptake mechanism involving Na+-dependent concentrative transporters localized at the plasma membrane level. Consistently, 1 and 3 showed higher cytotoxicity with respect to complex 2 also suggesting selective possible applications as antiviral/antitumor drugs among the used model compounds.

NMR studies of models having the Pt(d(GpG)) 17-membered macrocyclic ring formed in DNA by platinum anticancer drugs: Pt complexes with bulky chiral diamine ligands.

The highly distorted Pt(d(G*pG*)) (G* = N7-platinated G) 17-membered macrocyclic ring formed by cisplatin anticancer drug binding to DNA alters the structure of the G*G* base pair steps, canting one base, and increases dynamic motion, complicating solution structural studies. However, the ring appears to favor the HH1 conformation (HH1 denotes head-to-head guanine bases, 1 denotes the normal direction of backbone propagation). Compared to cisplatin, analogues with NH groups in the carrier ligand replaced by bulky N-alkyl groups are more toxic and less active and form less dynamic adducts. To examine the molecular origins for the biological effects of steric bulk, we evaluate Me(4)DABPt(d(G*pG*)) models; the bulk and chirality of Me(4)DAB (N,N,N',N'-tetramethyl-2,3-diaminobutane with S,S or R,R configurations at the chelate ring carbons) impede dynamic motion and enhance the utility of NMR methods for identifying and characterizing conformers. Unlike past studies of adducts with such bulky carrier ligands, in which no HH conformer was found, the Me(4)DABPt(d(G*pG*)) adducts did form the HH1 conformer, providing compelling evidence that the sugar-phosphate backbone can impose constraints sufficient to overcome the alkyl-group steric effects. The HH1 conformer exhibits no significant canting. The (S,S)-Me(4)DABPt(d(G*pG*)) adduct has the least amount of the "normal" HH1 conformer and the greatest amount of the ΔHT1 conformer (ΔHT1 = head-to-tail G* bases with Δ chirality) ever observed (88% under some conditions). Thus, our results lead us to hypothesize that the low activity and high toxicity of analogues of cisplatin having carrier ligands with N-alkyl groups arise from the low abundance and minimal canting of the HH1 conformer and possibly from the adverse effects of an abundant ΔHT1 conformer. The new findings advance our understanding of the chemistry of the Pt(d(G*pG*)) macrocyclic ring and of the effects of carrier-ligand steric bulk on the properties of the ring.

ERAS pathway in colorectal surgery: structured implementation program and high adherence for improved outcomes.

Although there is clear evidence that an Enhanced Recovery After Surgery (ERAS) program in colorectal surgery leads to significantly reduced morbidity rates and length of hospital stay (LOS), it is still unclear what modalities and levels of implementation of the program are necessary to achieve these results. The purpose of this study is to analyze the methods and results of the first year of structured implementation of a colorectal ERAS program in two surgical units of the Azienda Sanitaria Unica Regionale (ASUR) Marche in Italy. A two-center observational study on a prospectively maintained database was performed on 196 consecutive colorectal resections (excluding emergencies and American Society of Anesthesiologists class > III cases) over a 1-year period. More than 50 variables including adherence to the individual items of the ERAS program were considered. Primary outcomes were overall morbidity, major morbidity, mortality and anastomotic leakage rates; secondary outcomes were LOS, re-admission and re-operation. The results were evaluated by univariate and multivariate analyses through logistic regression. After a median follow-up of 39.5 days, we recorded complications in 72 patients (overall morbidity 36.7%), major complications in 14 patients (major morbidity 7.1%), 6 deaths (mortality 3.1%), anastomotic dehiscence in 9 cases (4.9%), mean overall LOS of 6.6 days, 10 readmissions (5.1%) and 13 reoperations (6.7%). The mean adherence rate to the items of the ERAS program was 85.4%, showing a significant dose-effect curve for overall and major morbidity rates, anastomotic leakage rates and LOS. The implementation methods of a colorectal ERAS program in this study led to a high adherence (> 80%) to the program items. High adherence had significant effects also on major morbidity and anastomotic leakage rates.

Synthesis and Evaluation of the Cytotoxic Activity of Water-Soluble Cationic Organometallic Complexes of the Type [Pt(η1-C2H4OMe)(L)(Phen)]+ (L = NH3, DMSO; Phen = 1,10-Phenanthroline).

Starting from the [PtCl(η1-C2H4OMe)(phen)] (phen = 1,10-phenanthroline, 1) platinum(II) precursor, we synthesized and characterized by multinuclear NMR new [Pt(η1-C2H4OMe)(L)(phen)]+ (L = NH3, 2; DMSO, 3) complexes. These organometallic species, potentially able to interact with cell membrane organic cation transporters (OCT), violating some of the classical rules for antitumor activity of cisplatin analogues, were evaluated for their cytotoxicity. Interestingly, despite both complexes 2 and 3 resulting in greater cell uptake than cisplatin in selected tumor cell lines, only 3 showed comparable or higher antitumor activity. General low cytotoxicity of complex 2 in the tested cell lines (SH-SY5Y, SK-OV-3, Hep-G2, Caco-2, HeLa, MCF-7, MG-63, ZL-65) appeared to depend on its stability towards solvolysis in neutral water, as assessed by NMR monitoring. Differently, the [Pt(η1-C2H4OMe)(DMSO)(phen)]+ (3) complex was easily hydrolyzed in neutral water, resulting in a comparable or higher cytotoxicity in cancer cells with respect to cisplatin. Further, both IC50 values and the uptake profiles of the active complex appeared quite different in the used cell lines, suggesting the occurrence of diversified biological effects. Nevertheless, further studies on the metabolism of complex 3 should be performed before planning its possible use in tissue- and tumor-specific drug design.

Role of percutaneous cholecystostomy in all-comers with acute cholecystitis according to current guidelines in a general surgical unit.

Acute calculous cholecystitis (ACC) is a very common complication of gallstone-related disease. Its currently recommended management changes according to severity of disease and fitness for surgery. The aim of this observational study is to assess the short- and long-term outcomes in all-comers admitted with diagnosis of ACC, treated according to 2013 Tokyo Guidelines (TG13). A retrospective analysis was conducted on a prospectively maintained database of 125 patients with diagnosis of ACC consecutively admitted between January 2017 and September 2019, subdivided in three groups according to TG13: percutaneous cholecystostomy (PC group), cholecystectomy (CH group), and conservative medical treatment (MT group). The primary end point was a composite of morbidity and/or mortality rates; the secondary end points were ACC recurrence, readmission, need for cholecystectomy rates and overall length of hospital stay (LOS). After a median follow-up of 639 days, overall morbidity rate was 20.8% and mortality rate was 6.4%. Death was directly related to AC during the index admission in two out of eight cases. There were no significant differences in primary end point according to the treatment group. Concerning secondary end points, ACC recurrence rate was not significantly different after PC (10.0%) or MT (9.1%); the readmission rates were significantly higher (p < 0.0001) in the MT group (48.5%) and in the PC group (25.0%) than in the CH group (5.8%); need for cholecystectomy rates was significantly higher (p < 0.0001) in the MT group (42.4%) than in the PC group (20.0%); median overall LOS was significantly higher in the PC (16 days) than in the MT (9 days) and than in the CH group (5 days). PC is an effective and safe rescue procedure in high-risk patients with ACC, representing a definitive treatment in 80% of cases of this specific subgroup.