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Adequate bowel cleansing is critical for a high-quality colonoscopy because it affects diagnostic accuracy and adenoma detection. Nevertheless, almost a quarter of procedures are still carried out with suboptimal preparation, resulting in longer procedure times, higher risk of complications, and higher likelihood of missing lesions. Current guidelines recommend high-volume or low-volume polyethylene glycol (PEG)/non-PEG-based split-dose regimens. In patients who have had insufficient bowel cleansing, the colonoscopy should be repeated the same day or the next day with additional bowel cleansing as a salvage option. A strategy that includes a prolonged low-fiber diet, a split preparation regimen, and a colonoscopy within 5 h of the end of preparation may increase cleansing success rates in the elderly. Furthermore, even though no specific product is specifically recommended in the other cases for difficult-to-prepare patients, clinical evidence suggests that 1-L PEG plus ascorbic acid preparation are associated with higher cleansing success in hospitalized and inflammatory bowel disease patients. Patients with severe renal insufficiency (creatinine clearance < 30 mL/min) should be prepared with isotonic high volume PEG solutions. Few data on cirrhotic patients are currently available, and no trials have been conducted in this population. An accurate characterization of procedural and patient variables may lead to a more personalized approach to bowel preparation, especially in patients undergoing resection of left colon lesions, where intestinal preparation has a poor outcome. The purpose of this review was to summarize the evidence on the risk factors influencing the quality of bowel cleansing in difficult-to-prepare patients, as well as strategies to improve colonoscopy preparation in these patients., Competing Interests: Conflict-of-interest statement: All authors have no proprietary, financial, professional, or other personal interest of any nature or kind in any product, service, and/or company that could be construed as influencing the position presented in, or the review of this manuscript., (©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.)

Hepatitis C virus (HCV) is one of the leading causes of chronic liver disease, cirrhosis, and hepatocellular carcinoma, resulting in major global public health concerns. The HCV infection is unevenly distributed worldwide, with variations in prevalence across and within countries. The studies on molecular epidemiology conducted in several countries provide an essential supplement for a comprehensive knowledge of HCV epidemiology, genotypes, and subtypes, along with providing information on the impact of current and earlier migratory flows. HCV is phylogenetically classified into 8 major genotypes and 57 subtypes. HCV genotype and subtype distribution differ according to geographic origin and transmission risk category. Unless people with HCV infection are detected and treated appropriately, the number of deaths due to the disease will continue to increase. In 2015, 1.75 million new viral infections were mostly due to unsafe healthcare procedures and drug use injections. In the same year, access to direct-acting antivirals was challenging and varied in developing and developed countries, affecting HCV cure rates based on their availability. The World Health Assembly, in 2016, approved a global strategy to achieve the elimination of the HCV public health threat by 2030 (by reducing new infections by 90% and deaths by 65%). Globally, countries are implementing policies and measures to eliminate HCV risk based on their distribution of genotypes and prevalence., Competing Interests: The authors declare that they have no conflict of interest, (© Acta Gastro-Enterologica Belgica.)

Background: Inflammatory bowel disease (IBD) is a multi-factorial systemic disorder which involves immune, genetic and environmental factors. Stress, in its various forms, plays an important role in gastrointestinal diseases and, in particular, in IBD., Methods: Here, we focus on the environmental stressors in different aspects of IBD (pathogenesis, course and severity of disease) and, in particular, will evaluate the mechanisms by which they may influence IBD., Results: The effect of stress on IBD might be mediated by autonomic nervous system and hypothalamic pituitary adrenal axis. These nervous pathways are part of the so called "brain-gut axis" which links gastrointestinal integrity and functions to central nervous system acting through the increase of intestinal permeability, bacterial translocation and cytokines network., Conclusion: The incidence of emotional disorders is higher in Crohn's Disease and Ulcerative Colitis compared to general population. Moreover, depression and anxiety influence the course and the severity of the underlying intestinal disease. Hence, it is important to consider appropriate psychological therapy in IBD patients., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

The anticancer activity of cisplatin is triggered by its formation of intrastrand adducts involving adjacent G residues of DNA. To obtain information on the different conformers that can be formed, carrier ligands such as 2,2'-bipiperidine, which provide large steric bulk near the platinum coordination plane and decrease the dynamic motion about the Pt-N7 bonds, were introduced ("retro-modelling" approach). In the present study we investigate the effect of cis-1,4-diaminocyclohexane (cis-1,4-DACH) on the formation, stability, and stereochemistry of (cis-1,4-DACH)Pt(ss-oligo) adducts (ss-oligo = d(GpG) with 3'- and/or 5'-substituents). Interesting features of this ligand, absent in previous retro-modelling studies, include the large bite angle (expected to impede the ease of interconversion between possible conformers), the presence of two protons on each nitrogen (a characteristic associated with antitumor activity), and the absence of chiral centres. The use of cis-1,4-DACH has made it possible to detect different conformers in a system containing a primary diamine carrier ligand associated with anticancer activity and to confirm the previous hypothesis that the coexistence of different conformers established in studies of retro models having relatively bulky ligands is not an artefact resulting from carrier-ligand bulk. Moreover, the data for the (cis-1,4-DACH)Pt(d(GpG)) and (cis-1,4-DACH)Pt(d(GGTTT)) adducts indicate that at a temperature close to the physiological one (40 °C) HH1 and ΔHT1 conformers are present in comparable amounts. In contrast, at low temperature (close to 0 °C) the equilibrium shifts dramatically toward the more stable HH1 conformer (for the (cis-1,4-DACH)Pt(d(TGGT)) adduct the HH1 conformer is always dominant, even at high temperature). Notably, (cis-1,4-DACH)PtCl2 (Kiteplatin) has been recently reinvestigated and found to be particularly active against colorectal cancer (including oxaliplatin-resistant phenotypes).

Background: Gastroparesis is a disorder characterized by delayed gastric emptying of a meal in the absence of a mechanical gastric outlet obstruction. Idiopathic gastroparesis is at least as common as diabetic gastroparesis in most case series, and the true prevalence of gastroparesis is unknown., Results: We report here an interesting case of idiopathic gastroparesis characterized by sudden onset in a female patient. The diagnosis was confirmed by ultrasonographic study of gastric emptying and electrogastrography, by gastric endoscopy/histology, and finally by allergy tests. The disorder was found to be due to a rare cause, namely an allergic predisposition. In fact, our patient, who demonstrated an allergy to gold salts, had drunk a glass of a liqueur containing gold flakes and developed an eosinophilic aggregation in the gastric mucosa observed at gastric endoscopy/histology. The symptoms disappeared after steroid administration., Conclusion: Our experience suggests that gastric histology and close enquiry into any history of allergy may be useful diagnostic tools in cases of idiopathic gastroparesis.

Oxidative addition and reductive elimination are fundamental processes in transition-metal chemistry. New interest in this field has been generated by the exploitation of platinum(IV) complexes as antitumor drugs. The two extra ligands can be used to render these species more resistant to attack by biological nucleophiles compared to their platinum(II) counterparts, to anchor additional pharmacologically active moieties, or, finally, to target the drug to specific sites by conferring responsiveness to some type of chemotaxis. On the other hand, platinum(IV) species are considered to be prodrugs and to require reduction to Pt(II) to become active. Thus, reductive elimination promoted by biological reducing agents becomes an important issue and it too could be exploited for targeting purposes. In this paper, we investigated the oxidation step in more detail and shown that, independent of the solvent used, a solvent molecule assists the reaction by entering in a trans position with respect to the attacking oxidant. In the case of bifunctional solvent molecules, such as dimethylsulfoxide, both S- and O-coordinated species are formed, the latter being thermodynamically favored. The substitution of the axially coordinated solvent molecule by a free chloride ion is found to be quite slow in organic solvents, as well as in water. It is also shown that the intermediate solvato-species can be exploited for binding just one molecule of another substrate in the axial position., (This journal is © The Royal Society of Chemistry 2011)

In [PtCl2(cis-1,4-DACH)] (DACH = diaminocyclohexane), the N-Pt-N bite angle (> or =97 degrees , as determined by X-ray diffraction analysis) is much larger than those found in other Pt complexes with bidentate diamines or in cisplatin (approximately 91 degrees ). Hence, the possibility exists that in (cis-1,4-DACH)PtG 2 adducts, rotation of the G's around the Pt-N7 bonds is slowed enough to allow observation of different conformers. In accord with this prevision, decreasing the temperature to 238 K enabled us to observe different conformers of (cis-1,4-DACH)Pt(5'-GMP) 2 (GMP = guanosine monophosphate). This observation is the first case in which such conformers for a platinum derivative with primary diamines and untethered guanines have been resolved and represents the closest model to clinically effective cisplatin obtained to date. We also found that the presence of the 1,4-DACH ligand increased the intensity of the circular dichroism signal stemming from the dominance of an HT conformer (DeltaHT in the adduct with 3'-GMPs and LambdaHT in the adduct with 5'-GMPs).

A peripheral benzodiazepine receptor (PBR) ligand (TZ6, 5) has been selected as receptor-mediated carrier for antitumor cisplatin-like compounds. Compound 5, containing a thiazole ring in position 2 of the imidazopyridine nucleus, is able to act as a dinitrogen chelate toward platinum. The resulting complex, cis-[PtCl2(5)], that is, compound 8, has been fully characterized by NMR techniques and has been shown to possess affinity and selectivity for the PBR comparable to those of 5 (IC50 of 4.6 and 2.81 nM for 8 and 5, respectively; selectivity indexes for PBR greater than 10,000 for both compounds). Hence, a platinum moiety cross-linking the imidazopyridine and the thiazole aromatic rings does not alter the affinity for PBR. The same cross-linking could be responsible for the tendency of 8 to associate in dimers. The equilibrium between monomer and dimer has been investigated by NMR spectroscopy and the corresponding constant determined.