2a 2c Research Articles

Reactivity of diethyl benzylidenemalonates with secondary cyclic amine dimers in acetonitrile: Structure-reactivity relationships and mechanism

We report on a kinetic study for the nucleophilic addition reactions of diethyl 4-X-substituted benzylidenemalonates 1a-c (X = N(CH3)2, OCH3 and CH3) with N-nucleophiles, such as morpholine 2a, piperidine 2b and pyrrolidine 2c by UV–vis spectroscopy in acetonitrile solution at 20 °C. The Hammett plots demonstrate much better linear correlations with σp+ constants than with σp constants. These results are best interpreted in terms of ground state stabilization through resonance interactions between the electron-donating substituent and the CO2Et group. The effect of amine basicity on the reaction rate was examined quantitatively, leading to linear correlations with high βnuc values in the 0.82–0.93 range. The origin of the abnormally high βnuc values was interpreted in terms of dimer mechanism. Finally, with the help of our new proposed linear free energy relationship log k1K (20 °C) = sN (E + N) + log K, the stability of the dimer amines (K) have been evaluated from the measured apparent second-order rate constant (k1K) and the previously reported E, N and sN parameters of the employed electrophiles 1a-c and nucleophiles 2a-c. Additionally, a complementary theoretical study utilizing Density Functional Theory (DFT) with the B3LYP/6-311g(d,p) method was conducted in acetonitrile. An attempt is made to establish the correlation between equilibrium constant and stabilization energy the studied systems.

Whispered words and organizational dynamics: The nuanced evaluation of gossipers' personality and its effect on workplace advice seeking

Prior research has extensively studied workplace group dynamics within the gossip triad (i.e., sender, receiver, and target). This research shifts the focus to third-party observers outside the gossip triad, examining how they evaluate gossipers and non-gossipers, and whom they turn to for advice. Across five pre-registered experiments (N = 1400), the present work builds on an integrative definition of gossip and provides a functionalist account of observers' nuanced evaluation of gossipers' personality from a global perspective. Observers perceive gossipers as less moral and competent, but more sociable, than non-gossipers (Experiment 1). Consequently, observers are less likely to seek advice from gossipers (vs. non-gossipers) for tasks requiring high morality (e.g., enforcing ethical conduct; Experiment 2a) and high competence (e.g., managing excess inventory; Experiment 2b), yet more likely to do so for tasks requiring high sociability (e.g., organizing a welcome lunch; Experiment 2c). A moderation-of-process approach shows that incidental cues signaling morality, competence, and sociability influence observers' evaluations of and advice-seeking from gossipers (versus non-gossipers) on relevant tasks (Experiments 2a–2c). These findings remain robust in an incentive-compatible setting (Experiment 3). This research advances our understanding of observers' evaluation of gossipers and its implications for workplace advice seeking.

Synthesis of Thiophene-Fused Siloles through Rhodium-Catalyzed Trans-Bis-Silylation

Rhodium-catalyzed reactions of 3-ethynyl-2-pentamethyldisilanylthiophene derivatives (1a–1c) have been reported. At 110 °C, compounds 1a–1c reacted in the presence of a rhodium complex catalyst, yielding thiophene-fused siloles (2a–2c) through intramolecular trans-bis-silylation. To understand the production of 2a from 1a, the mechanism was investigated using density functional theory (DFT) calculations.

Survival Outcomes of Patients with Esophageal Cancer Who Did Not Proceed to Surgery after Neoadjuvant Treatment.

This retrospective study examined outcomes in esophageal squamous cell carcinoma (ESCC) patients who did not undergo surgical resection after neoadjuvant chemoradiotherapy (nCRT). Patients receiving nCRT between 2012 and 2020 were divided into two groups: group 1 (scheduled surgery) and group 2 (no surgery). Group 2 was further categorized into subgroups based on reasons for not proceeding to surgery: group 2a (disease progression), group 2b (poor general conditions), and group 2c (patient refusal). Overall survival (OS) was the primary outcome. Group 1 comprised 145 patients, while subgroups 2a, 2b, and 2c comprised 24, 16, and 31 patients, respectively. The 3-year OS rate was significantly lower in group 2 compared with group 1 (34% versus 56%, p < 0.001). A subgroup analysis showed varying 3-year OS rates: 13% for group 2a, 25% for group 2b, and 58% for group 2c (p < 0.001). Propensity score matching for group 2c and group 1 revealed no significant difference in 3-year OS rates (p = 0.91). One-third of ESCC patients receiving nCRT did not undergo surgical resection. Overall survival in this group was generally poorer, except for those who refused surgery (group 2c).

Kristalline Anionen auf Basis klassischer N‐Heterocyclischer Carbene

AbstractDie ersten stabilen Anionen K[SIPrBp] (4 a‐K) und K[IPrBp] (4 b‐K) (SIPrBp=BpC{N(Dipp)CH2}2, IPrBp=BpC{N(Dipp)CH}2; Bp=4‐PhC6H4; Dipp=2,6‐iPr2C6H3), die von klassischen N‐heterocyclischen Carbenen (NHCs) abgeleitet sind (d. h. SIPr und IPr), wurden als violette kristalline Feststoffe isoliert. 4 a‐K und 4 b‐K wurden durch die Reduktion der neutralen Radikale [SIPrBp] (3 a) bzw. [IPrBp] (3 b) mit KC8 hergestellt. Die Radikale 3 a und 3 b sowie [Me‐IPrBp] (3 c) (Me−IPrBp=BpC{N(Dipp)CMe}2) liegen als kristalline Feststoffe vor, wenn die entsprechenden 1,3‐Imidazoli(ni)umbromide (SIPrBp)Br (2 a), (IPrBp)Br (2 b) und (Me‐IPrBp)Br (2 c) mit KC8 umgesetzt werden. Die Cyclovoltammogramme von 2 a–2 c zeigen zwei reversible Ein‐Elektronen‐Redoxprozesse im Bereich von −0.5 bis −2.5 V, die den Radikalen 3 a–3 c und den Anionen (4 a–4 c)− entsprechen. Quantenchemische Berechnungen deuten auf einen geschlossenschaligen Singulett‐Grundzustand für (4 a–4 c)− mit einer Singulett‐Triplett‐Energielücke von 17–24 kcal mol−1 hin.

Importance of Delayed Reperfusions in Patients With Incomplete Thrombectomy.

Background:There is paucity of data regarding the effects of delayed reperfusion (DR) on clinical outcomes in patients with incomplete reperfusion following mechanical thrombectomy. We hypothesized that DR has a strong association with clinical outcome in patients with incomplete reperfusion after mechanical thrombectomy (expanded Thrombolysis in Cerebral Infarction, 2a–2c).Methods:Single-institution’s stroke registry retrospective analysis of patients admitted from February 2015 to December 2020. DR was defined as the absence of any perfusion delay on ≈24-hour contrast-enhanced follow-up perfusion imaging, whereas persistent perfusion deficit denotes a perfusion delay corresponding to the catheter angiographic deficit directly after the intervention. The association of perfusion outcome (DR versus persistent perfusion deficit) with the occurrence of new infarcts and 90-day functional independence (modified Rankin Scale score 0–2) was evaluated using logistic regression analyses. Comparison of predictive accuracy was evaluated by calculating area under the curve for models with and without perfusion outcome.Results:In 566 patients (mean age 74, 49.6% female), new infarcts in the incomplete reperfusion areas were less common in DR versus persistent perfusion deficit patients (small punctiform: 17.1% versus 25%, large confluent: 7.9% versus 63.2%; P=0.001). After adjustment for confounders, DR was a strong predictor of functional independence (adjusted odds ratio, 2.37 [95% CI 1.34–4.23]). There was a significant improvement in predictive accuracy of functional independence when perfusion outcome was added to expanded Thrombolysis in Cerebral Infarction alone (area under the curve 0.57 versus 0.62, P=0.01).Conclusions:Occurrence of DR is closely associated with tissue outcome and functional independence. DR may be an independent prognostic parameter, suggesting it as a potential outcome surrogate for medical rescue therapies.

Synthesis of Pyridine-Fused Siloles by Palladium-Catalyzed Intramolecular Bis-Silylation.

Silole derivatives are attracting significant attention as new functional materials with excellent electronic and photophysical properties. Thus, the development of synthesis methods to afford such derivatives is highly desirable. Herein, the synthesis of pyridine-fused siloles under the conditions of the Sonogashira coupling reaction is described. The reactions of 2-bromo-3-(pentamethyldisilanyl)pyridine (1) with ethynylbenzene derivatives in the presence of PdCl2(PPh3)2-CuI as a catalyst afforded the corresponding pyridine-fused siloles (2a–2c) through intramolecular trans-bis-silylation. DFT calculations were also performed to understand the reaction mechanism. This paper is the first to report on the successful use of palladium catalysts in the trans-bis-silylation of alkynes with disilanes.

The retrograde evolution of F-rich skarns: Clues from major and trace element chemistry of garnet, scheelite, and vesuvianite from the Belka Pahar wollastonite deposit, India

Skarn settings host many ore deposits and are ideal for studying the mobility of elements in hydrothermal fluids. Belka Pahar, in the Sirohi district of Rajasthan (NW India), is the largest wollastonite deposit in India (estimated wollastonite reserve of 56 million tonnes). No detailed textural and geochemical study has been conducted on these skarn rocks. In this study, we use petrographic studies, and major-trace element chemistry of skarn minerals from Belka Pahar to deduce the sequence of mineral transformations and to characterize the changes in the composition of the fluid with the progress of fluid-rock interaction during skarn formation. Two major rock types from the exoskarn have been considered for detailed study: prograde skarn rocks comprising pyroxene, garnet, wollastonite, quartz, and calcite, and retrograde skarn rocks containing garnet, scheelite, vesuvianite, fluorite, and sphalerite. Two types of garnet are recognized in the rocks-texturally earlier prograde garnet (Grt 1 ) and texturally late retrograde oscillatory-zoned Grt 2 , which is further sub-divided into three generations Grt 2a , Grt 2b and Grt 2c . The Grt 1 (And 27–47 ) and Grt 2a (And 50–60 ) have high Y-concentrations, and high HREE/LREE ratio, which is in stark contrast to the late Grt 2b (And 40–50 ) and Grt 2c (And 27–40 ), which is characterized by high F, low Y-concentrations, and HREE-depleted REE patterns. The chemistry of different generations of garnet suggests a shift from diffusive to more advective metasomatic conditions and increasing water/rock ratio, accompanied by a shift in pH of the fluid from neutral to acidic to weakly acidic. The crystallization of F-rich garnet, vesuvianite, and fluorite indicates an increase in F-concentration in the later-stage fluid. An increase of W concentration in Grt 2b and co-precipitation of scheelite and fluorite also suggests its possible link with scheelite crystallization. The high grossular component of Grt 2b and Grt 2c suggests transport of Al in the hydrothermal fluid as F-complexes. The hydrothermal fluid composition extrapolated from scheelite chemistry agrees with the LREE enriched patterns exhibited by all skarn minerals. Principal Component Analysis done on a compiled dataset of skarn garnet shows that its trace element composition can be a useful proxy of fluid composition and can be used as an indicator of associated ore type. • Garnet composition is a useful proxy of fluid chemistry in the skarn system. • High F concentration in fluid enhanced Al mobilization, forming grossular-rich garnet. • Scheelite precipitation is linked to interaction of F-rich fluid with calc-silicate rocks. • PCA shows control of fluid composition on garnet chemistry. • Garnet trace element chemistry is a robust proxy of ore-genetic association.

Association of Intravenous Thrombolysis with Delayed Reperfusion After Incomplete Mechanical Thrombectomy

PurposeTreatment of distal vessel occlusions causing incomplete reperfusion after mechanical thrombectomy (MT) is debated. We hypothesized that pretreatment with intravenous thrombolysis (IVT) may facilitate delayed reperfusion (DR) of residual vessel occlusions causing incomplete reperfusion after MT.MethodsRetrospective analysis of patients with incomplete reperfusion after MT, defined as extended thrombolysis in cerebral infarction (eTICI) 2a–2c, and available perfusion follow-up imaging at 24 ± 12 h after MT. DR was defined as absence of any perfusion deficit on time-sensitive perfusion maps, indicating the absence of any residual occlusion. The association of IVT with the occurrence of DR was evaluated using a logistic regression analysis adjusted for confounders. Sensitivity analyses based on IVT timing (time between IVT start and the occurrence incomplete reperfusion following MT) were performed.ResultsIn 368 included patients (median age 73.7 years, 51.1% female), DR occurred in 225 (61.1%). Atrial fibrillation, higher eTICI grade, better collateral status and longer intervention-to-follow-up time were all associated with DR. IVT did not show an association with the occurrence of DR (aOR 0.80, 95% CI 0.44–1.46, even in time-sensitive strata, aOR 2.28 [95% CI 0.65–9.23] and aOR 1.53 [95% CI 0.52–4.73] for IVT to incomplete reperfusion following MT timing <80 and <100 min, respectively).ConclusionA DR occurred in 60% of patients with incomplete MT at ~24 h and did not seem to occur more often in patients receiving pretreatment IVT. Further research on potential associations of IVT and DR after MT is required.

Phosphorus–nitrogen compounds: Part 60: Synthesis of hexaminomonoferrocenyl-spiro(N/O)cyclotetraphosphazenes: Spectral and electrochemical properties, tuning of redox feature, and antituberculosis activity

In the present investigation, the condensation reaction of octachlorocyclotetraphosphazene, N4P4Cl8 (1) (tetramer, OCCP), with sodium 3-(N-ferrocenylmethylamino)-1-propanoxide (L) resulted in the formation of the starting compound hexachloromonoferrocenylspiro(N/O)cyclotetraphosphazene (2). Thereafter, reactions of spiro (2) with excesses of 1-(2-aminoethyl)pyrrolidine, 1-(2-aminoethyl)piperidine and 4-(2-aminoethyl)morpholine in dry THF gave hexaaminomono-ferrocenylspiro(N/O)cyclotetraphosphazenes, 2a, 2b, and 2c, respectively. These new products were prepared for investigation of spectral and electrochemical properties, tuning of redox features, and examination of antituberculosis activities. The structures of 2a–2c were elucidated using elemental analysis, mass spectrometry (ESI-MS), FTIR, HMBC, HSQC, 1H, 13C {1H}, and 31P {1H} NMR data. The electrochemical behavior of these products containing monoferrocenyl group was investigated. Their use as potential alternative electrolyte redox couples for dye-sensitized solar cells (DSSC) was examined. The findings may inspire solar cell studies to explore the redox mediator behind the working mechanisms of DSSCs. Conversely, the antituberculosis activities of three compounds were examined against Mycobacterium tuberculosis H37Rv. The MIC values of 2a and 2 b were found to be as 30 and 35 µg/mL, respectively, against the H37Rv reference strain.

Synthesis, chemical and physical properties of lanthanide(III) (Nd, Gd, Tb) complexes derived from (E)-ethyl 4-(2-hydroxybenzylideneamino)benzoate

The 1:2 reaction between Ln(NO3)3·6H2O (1) (Ln = Nd (a), Gd (b) or Tb (c)) and ((E)-ethyl 4-((2-hydroxybenzylidene)amino)benzoate) (LN,OH) in ethanol has provided access to the complexes [LnIII(LNH,O)2(NO3)3(H2O)] (2a–c) in good yield. The isomorphous structures of 2a–c have been determined by single-crystal X-ray crystallography. The LnIII ions in 2a–c are coordinated by 9 oxygen atoms: two from the phenolate oxygen atoms of the Schiff bases, six from three chelating nitrato groups and one aqua ligand. The ligands LN,OH behave as monodentate phenolate O–donors, whereby an additional hydrogen atom is bonded to the imino nitrogen atom, resulting in a formally neutral ligand that adopts an exceptionally unusual coordination mode engaging in the zwitterionic form. The nine donor atoms that define the coordination polyhedra surrounding the LnIII ion are best described as capped square antiprisms. The crystal structures are based on a variety of intermolecular interactions. Hirshfeld surface analysis was used to assess the degree of interactions between the molecules. Susceptibility measurements on 2a–2c confirm the occurrence of the free ion ground 2S+1LJ state at room temperature. However, the magnetization measurements at 2 K revealed a lack of saturation at the highest applied field of 70,000 Oe for both 2a and 2c, indicating the presence of substantial magnetic anisotropy in these compounds. On the other hand, 2b exhibits perfect paramagnetic behavior with magnetic saturation at high fields, indicating the absence of significant magnetic anisotropy in this compound. Solid-state IR and UV/VIS data are discussed in terms of the structural features. Solid 2a–c emit in the visible region upon UV-Excitation with the emission exhibiting dopant characteristics.

Catalytic reductive ring opening of epoxides enabled by zirconocene and photoredox catalysis

Catalytic reductive ring opening of epoxides enabled by zirconocene and photoredox catalysis

Silver(I) complexes with phenolic Schiff bases: Synthesis, antibacterial evaluation and interaction with biomolecules.

Novel Ag(I) complexes (2a–2c) with phenolic Schiff bases were synthesized using 4,6-di-tert-butyl-3-(((5-mercapto-1,3,4-thiadiazol-2-yl)imino)methyl)benzene-1,2-diol (1a), 4,6-di-tert-butyl-3-(((4-mercaptophenyl)imino)methyl)benzene-1,2-diol (1b), and 4,6-di-tert-butyl-3-(((3-mercaptophenyl)imino)methyl)benzene-1,2-diol (1c). They were examined by elemental analysis, FT-IR, UV-Vis, 1H-NMR spectroscopy, XRD, cyclic voltammetry, conductivity measurements, and biological methods. The complexes are characterized by distorted geometry of the coordination cores AgN2S2 (2c), AgNS (2b) and AgS2 (2a). These stable complexes were not typified by the intramolecular redox reaction in organic solvents resulting in the formation of silver nanoparticles (AgNPs). Antibacterial activity of 1a–1c and 2a–2c was evaluated in comparison with AgNPs and commonly used antibiotics. All the complexes were more active than the ligands against the bacteria tested (14), but they were less active than AgNPs and commonly used antibiotics. Both 1a–1c and their complexes 2a–2c exhibited the capability for the bovine heart Fe(III)-Cyt c reduction. The ligands 1b and 1c were characterized by the highest reduction rate among the compounds under study, and they showed a higher reducing ability (determined by cyclic voltammetry) as compared with that of their Ag(I) complexes 2b and 2c.

Substitution of the chlorido ligand for PPh3 in anticancer organoruthenium complexes of sulfonamide-functionalized pyridine-2-carbothioamides leads to high cytotoxic activity

The functionalization of Ru(arene) complexes with bioactive moieties is a promising approach for modulating their biological properties. This strategy may result in compounds with synergistic biological effects which may be capable of overcoming major drawbacks of currently used chemotherapeutics. A series of RuII(η6-p-cymene)Cl complexes 1a–1c comprising sulfonamide and pyridine-2-carbothioamide (PCA) ligands were designed to evaluate their antiproliferative potency in cancer cells. The ligands and their corresponding organoruthenium complexes were characterized by NMR spectroscopy, elemental analysis, ESI-MS analysis and the molecular structure of 1a was determined by X-ray diffraction analysis. In vitro cytotoxic assays showed that the chlorido complexes 1a–1c are inactive. However, the cytotoxicity was significantly improved when the labile chlorido ligand was replaced with triphenylphosphine in 2a–2c. The most active complex 2c showed IC50 values as low as 1.9 ± 0.5 µM in cervical carcinoma SiHa cells compared to 3.0 ± 1.1 µM for the chemotherapeutic agent cisplatin.

Predicting the impact of formation protocols on battery lifetime immediately after manufacturing

Predicting the impact of formation protocols on battery lifetime immediately after manufacturing

Synthesis, chemo-informatics, and anticancer evaluation of fluorophenyl-isoxazole derivatives

Abstract The current study aimed to design and synthesize a novel series of fluorophenyl-isoxazole-carboxamide derivatives and evaluate their antiproliferative activities. Anticancer activities of the novel compounds were evaluated by MTS assay against four cancer cell lines, including liver (Hep3B, HepG2), cervical (HeLa), and breast (MCF-7), and α-fetoprotein tumor marker, cell cycle analysis, and annexin V tests. Chemo-informatics analysis showed that all synthesized derivatives 2a–2f obeyed Lipinski’s rule. Compound 2f was the most potent compound against Hep3B and Hep-G2 cancer cell lines with IC50 values of 5.76 and 34.64 µg/mL, respectively. Moreover, compounds 2a–2c and 2e showed potent inhibitory activity against Hep3B with an IC50 value range of 7.66–11.60 µg/mL. Hep3B secretions of α-fetoprotein (α-FP) results showed that compound 2f reduced the secretion of Hep3B to 168.33 ng/mL and compound 2d reduced the secretion to value approximately 598.33 ng/mL, in comparison with untreated cells’ value of 1116.67 ng/mL. Furthermore, cell cycle analysis showed that the 2f compound induced arrest in the G2-M phase in 6.73% of the total cells and that was lower than the activity of the positive control doxorubicin (7.4%). Moreover, 2b and 2f compounds reduced the necrosis rate of Hep3B to 4-folds and shifted the cells to apoptosis.

Synthesis of poly[1-phenyl-2-(fluoren-2-yl)acetylene]s bearing trimethylsilyl groups at the fluorene 9-position to give highly gas-permeable polymer membranes

Four types of 1-phenyl-2-(fluoren-2-yl)acetylene bearing SiMe3 groups at the 9-position of fluorene (1a–1d) were synthesized and polymerized in the presence of TaCl5/n-Bu4Sn to yield the corresponding polymers (2a–2d). Membranes fabricated from 2a–2c exhibited fairly high gas permeabilities (PO2: 1600–7000 barrer), while membrane 2d was too brittle for testing. As the number of SiMe3 groups in the monomer unit increased, the gas permeability of the polymer membrane increased. Desilylated membranes 3a–3c were obtained by the desilylation of membranes 2a–2c, respectively. Desilylated polymers 3a–3c possessed identical chemical structures but different gas permeabilities (PO2: 2500–5800 barrer). Highly gas-permeable polymers 2c and 3c exhibited good stabilities against physical aging in terms of their gas permeabilities.

Side-Arm Assisted Anilido-Imine Based Rare-Earth Metal Complexes for Isoprene Stereoselective Polymerization.

Anilido-imine ligands o-C6H4(NHAr1)(CH=NAr2), in which Ar1 is 2,6-diisopropylbenzyl group and Ar2 contains fluorine (HL1) or methoxyl (HL2) group on ortho-position of phenyl substituent, were synthesized for constructing rare-earth metals based complexes of 1a–1c (HL1 based Sc, Lu, Y) and 2a–2c (HL2 based Sc, Lu, Y). Based on their NMR spectra and X-ray single-crystal structures, the side-arm group of -F and -OMe is identified to chelate to the corresponding central metal. The twisted angles between two planes formed by chelated heteroatoms (N, N, F for HL1 and N, N, O for HL2) are observed, in which the largest dihedral angle (53.3°) for HL1-Y and the smallest dihedral angle (44.32°) for HL2-Sc are detected. After being activated by AliBu3 and [Ph3C][B(C6F5)4], these catalysts showed great activity for isoprene polymerization. Bearing the same ligand HL1, smaller scandium based complex 1a and middle size of lutetium based 1b provided lower cis-1,4-selectivity (57.3% and 64.2%), larger yttrium complex 1c displayed high cis-1,4-selectivity (84%). Chelating by crowded HL2, small size of scandium complex 2a provided impressive trans-1,4-selectivity (93.0%), middle lutetium based 2b displayed non-selectivity and larger yttrium complex 2c showed clear cis-1,4-selectivity (83.3%). Moreover, 2a/AliBu3 system showed the quasi-living chain transfer capability.

How Resource Scarcity Influences the Preference for Counterhedonic Consumption

Abstract Eight studies show that resource scarcity can influence consumers’ preference for counterhedonic consumption and that the sense of control is an underlying driver of this effect. Using a large-scale field dataset covering 82 countries over a 10-year period, study 1 showed that individuals from countries with greater resources consumed horror movies to a greater extent, but this pattern was not found for other movie genres such as romance or documentary. The remaining studies used diverse experimental approaches and counterhedonic consumption contexts (e.g., movie, novel, haunted house attraction, game) to provide causal and process evidence. Specifically, inducing perceived resource scarcity lowered participants’ preference for counterhedonic consumption (studies 2A–2C). Consistent with the sense-of-control-based mechanism, experimentally lowering participants’ sense of control or boosting it moderated the effect of perceived resource scarcity on their preference for counterhedonic consumption (studies 3A and 3B). The degradation of the sense of control due to perceived resource scarcity mediated the effect (studies 4 and 5). These results add to the literature on conterhedonic consumption as well as resource scarcity and have important managerial implications.

The Management of the Open Abdomen - A Literature Review.

An essential component of the concept of "Damage control surgery", laparostomy is the procedure by which the abdomen is deliberately abandoned open, the visceroperitoneal contents being temporarily protected by multiple technical means. Actual classification: Grade 1, without viscero-parietal adhesions or fixity of the abdominal wall (lateralization), divided into: 1A clean, 1B contaminated and 1C enteral fistula -cutaneous skin is considered clean); Grade 2, which develops fixation is subdivided into: 2A clean, 2B contaminated and 2C enteral fistula; Grade 3, "frozen abdomen", is divided into: 3A clean and 3B contaminated; Grade 4, defined as enteroatmospheric fistula, is a permanent fistula associated with the presence of granulation tissue and a frozen abdomen. Indications of the open abdomen are: damage control surgery, abdominal compartment syndrome, peritonitis, severe acute pancreatitis, vascular emergencies. Temporary abdominal closure may be achieved by following methods: skin only closure, â??Bogota bagâ?Â, opsite Sandwich technique, absorbable mesh, non-absorbable mesh or commercial zipper, vaccum asisted closure, each with its own advantages and disadvantages. Regarding the definitive closure this can be achieved by non mesh and mesh mediated techniques. Component separation technique anterior and posterior should be considered the elective repair procedure in parietal defects after laparostomy. Although several studies have been published, there is still no consensus in the literature on the positioning of prosthetic material in relation to parietal planes. Some authors suggest better results (relative to the rate of recurrence and complications) for implantation in the "sublay" position. Open abdomen is an important tool in the arsenal of the emergency surgery. Classification, indications, methods of temporary abdominal closure are evolving, as well as management of enterocutaneous fistulas and fascial closure, therefore permanent update is neccessary to offer patients the best care.