Application of molecular machines in photoelectrochemistry

The paper presents an original integrated photo-electro-chemistry algorithm developed by the authors for the possibilities of application of molecular machines in photoelectrochemistry. Concerning molecular machines, five main directions have been approached: the representation of the studied system through computational programs, the calculation of reaction parameters based on HSAB principle, estimation of Coulomb blockade, predictions on the bondonic photovoltaic effect by bondonic spectral correlations, calculations of the thermodynamic indices of interconversion through the path integral formalism, and estimations about the corresponding binary logical systems

Incisional hernias – results of present therapy options

Sp. Sf. Pantelimon, București, Al XI-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova și cea de-a XXXIII-a Reuniune a Chirurgilor din Moldova „Iacomi-Răzeșu” 27-30 septembrie 2011Introducere: Hernia incizională este cea mai frecventă complicație după operațiile abdominale. Este dificil de estimat exact costul acestei patologii pentru societate. Dacă adăugam la costul intervenției chirurgicale și costul spitalizării, dificultățile operațiilor de recidivă multiplă, costul protezelor, morbiditățile pacienților neoperați, afectarea capacității de muncă și a calității vieții, vom avea magnitudinea problemei dezvoltate de această complicație redutabilă a tuturor intervențiilor chirurgicale. Material și metodă: Am analizat rezultatele mai multor studii de prestigiu ale unor colective românești și internaționale în domeniul herniilor incizionale. Rezultate: Din nefericire rezultatele globale ale tratamentului în hernia incizională oscilează între 12-63% pentru procedeele tisulare și între 2-36% pentru procedeele allopalstice. Abordul chirurgical este cel mai adesea bazat pe traditie si pe liberul arbitru, decat pe evidențe statistice sau ghiduri de tratament. Nu este deloc surprinzător faptul că, în ciuda noilor cuceriri în domeniul defectelor parietale și a folosirii explozive a protezelor, rata de re-operații pentru recidiva incizională se situează la același nivel. Concluzii: Componența operatorie ca unică etiologie în hernia incizională este supraestimată. Datorită faptului că și alți factori etiologici, cunoscuți sau nu, concura la apariția herniei incizionale și la re-recidivă, și datorită faptului că acești “factori” nu sunt deocamdată influențabili de tratamentul medical nu ne rămțne decât să analizăm lucid și responsabil factorii chirurg-dependenți. Greselile de tactică/tehnică chirurgicală trebuie evidențiate, explicate, și înlăturate. Soluția nu este o abordare pur tehnică, ci una fiziologică, în termeni de elasticitate, complianța și rezistența a întregului perete abdominal, deseori modificat profund de marile defecte incizionale.Introduction: incisional hernia is the most common complication after abdominal surgery. It is difficult to estimate the exact cost to society of this pathology. If we add to the cost of surgery and hospitalization costs, the difficulties of relapse multiple operations, the cost of prostheses, unoperated patient morbidity, impaired work capacity and quality of life, the magnitude of the problem we have developed this redoubtable complication of all surgical procedures. Methods: We analyzed the results of several studies of prestigious romanian and international collectives about incisional hernias. Results: Unfortunately, the overall results of treatment in incisional hernia procedures vary between 12-63% for tissular procedures and between 2-36% for allopalstic procedures. Surgical approach is most often based on tradition and the free will, rather than obvious statistical treatment guidelines. Not surprisingly, despite the new advancements in the field of herniology and the use of new parietal prosthesis, the rate of re-operations for recurrent incisional fall at the same level. Conclusions: Surgery as the only component in etiology of incisional hernias is overestimated. Due to the fact that other etiological factors, known or not compete in the emergence and re-incision hernia recurrence, and because these “factors” are not influenced by medical treatment for now, we are just lucid and analyze the factors responsible - surgeon dependent. Mistakes tactics/surgical technique must be highlighted, explained and removed. The solution is not a purely technical approach, but a physiological, in terms of elasticity, compliance and resistance of the entire abdominal wall

Surgical atitude in suppurative acute pancreatitis

UMF Carol Davila, București, Sp. Sf. Pantelimon, București, Al XI-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova și cea de-a XXXIII-a Reuniune a Chirurgilor din Moldova „Iacomi-Răzeșu” 27-30 septembrie 2011Introducere: Managementul chirurgical al pancreatitei acute severe(SAP) rămâne încă controversat. Stabilirea indicație chirurgicale și a momentului operator optim este în legătură directă cu morbiditatea și mortalitatea acestei afecțiuni. Decizia chirurgicală se bazează pe criterii clinice,morfologice- examenul computer-tomografic și criterii bacteriologice- necroza sterilă sau infectată. Infecția necrozei pancreatice reprezintă o indicație de necontestat pentru necrozectomia chirurgicală. Material și metodă: Din 2007 până în 2010, un total de 104 de pacienți cu diagnostic de SAP şi cu indicație de intervenție chirurgicală au fost admişi în secția de chirurgie generală. Rezultate: Valoarea medie a scorului APACHE II la internare a fost de 16,4 (în intervalul 8-35). Toți pacienții au necesitat intervenție chirurgicală. Mortalitatea generală a fost 13,4% (14 pacienți). Insuficiență multiplă de organ a fost evidențiată la 41 de pacienți (39,4%). Infarctul miocardic sau embolia pulmonară au fost cauzele de deces la 3 pacienți (2,88%). Vârsta (p <0.0002), scorul APACHE II la internare (p<0,0001) , prezența sau dezvoltarea insuficienței (unice sau multiple) de organ (p<0.002), infecțiile (p<0,02) şi gradul extensiei necrozei pancretice (p <0.04), gradul de control al necrosectomiei (p <0,0001) par a fi în directa relație cu supraviețuirea. Concluzii: Evaluarea chirurgicală, în dinamică,se bazează pe determinările de laborator proprii identificării sepsisului cât și pe o imagistică CT sau RMN care să cuprindă obligatoriu reconstrucții de calitate. Acestea vor asigura o evacuare completă a necrozelor infectate, încă de la intervenția primară.Introduction: Surgical management of severe acute pancreatitis (SAP) remains controversial. Establishing the surgical indication and the optimal timing for surgery is directly related to surgical morbidity and mortality. Surgical approach is based on clinical-morphological criterias, computer tomography criteria, bacteriological-sterile or infected necrosis of pancreas. Infected necrosis represent an unquestionable indication for surgery. Methods: From 2007 to 2010, a total of 104 patients with a diagnosis of SAP and indication for surgery were admitted in department of general surgery. Results: The mean APACHE II score on the day of admission was 16.4(range 8-35). All patients required operative therapy. The overall mortality was 13,4% (14 patients). Septic organ failure in 41 patients (39,4%) and myocardial infarction or pulmonary embolism in 3 patients (2,88%) were the causes of death. The patient’s age (p <0.0002), APACHE II scores at admission (p <0.0001), presence or development of (single or multiple) organ failure (p <0.002), infections (p <0.02) and extent (p <0.04) of pancreatic necrosis, and surgical control of local necrosis (p <0.0001) significantly determined survival. Conclusions: The surgical evaluation, in dynamics, is based on both the laboratory determinations proper to the identification of the sepsis, and also on a CT or MRI imagistics which must necessarily contain quality reconstructions. These will ensure a complete evaluation of the infected necrosis, from the primary intervention

Cyanomethylene-bis(phosphonate)-Based Lanthanide Complexes: Structural, Photophysical, and Magnetic Investigations

10 pagesInternational audienceThe syntheses, structural investigations, magnetic and photophysical properties of a series of 10 lanthanide mononuclear complexes, containing the heteroditopic ligand cyanomethylene-bis(5,5-dimethyl-2-oxo-1,3,2λ5-dioxa-phosphorinane) (L), are described. The crystallographic analyses indicate two structural types: in the first one, [LnIII(L)3(H2O)2]*H2O (Ln = La, Pr, Nd), the metal ions are eight-coordinated within a square antiprism geometry, while the second one, [LnIII(L)3(H2O)]*8H2O (Ln = Sm, Eu, Gd, Tb, Dy, Ho, Er), contains seven-coordinated LnIII ions within distorted monocapped trigonal prisms...

Réactions de substitution nucléophile sur le phosphore : synthèse et réactivité du 5,5-diméthyl-2-oxo-2-(1,3-dithiane-2-yl)-1,3,2-dioxaphosphorinane

International audienceWe describe the formation and reactivity of the lithiated carbanion of 5,5-dimethyl-2oxo-2-(1,3-dithian-2-yl)-1,3,2-dioxaphosphorinane 3b. The derived carbanion 2b is prepared in quantitative yield by internal quench condensation of 1,3-dithiane and 2-chloro-5,5-dimethyl-2oxo-1,3,2-dioxaphosphorinane 1b with two equivalents of LDA at low temperature. The carbanion 2b is reacted with a variety of ketones in one-carbon homologation reaction and a comparison with other reagents is done. chlorophosphates / dithiane / LDA / lithiated phosphonate esters / Horner-Wadsworth-Emmons reactionNous décrivons la préparation et la réactivité du carbanion lithié dérivé du 5,5-diméthyl-2- oxo-2-(1,3-dithian-2-yl)-1,3,2-dioxaphosphorinane 3b. Ce carbanion 2b est préparé quantitativement par addition simultanée du 1,3-dithiane et du 2-chloro-5,5-dimethyl-2-oxo-1,3,2- dioxaphosphorinane 1b à deux équivalents de LDA à basse température. La réactivité de 1b est évaluée vis-à-vis des cétones en réaction d'homologation d'un carbone et comparée à celle d'autres réactifs

Molecular devices and machines: Hybrid organic-inorganic structures

Objective: In this review we present the general principles that are at the basis of the construction of artificial molecular devices and machines and the main characteristics of these systems with a special focus for the kind of energy inputs needed to make them work. Methodology: By the bottom-up (chemical) approach science and technology move from micro- to nanoworld, and due to the nature of inputs (light and chemical) they move from electronics to photonics and chemi-onics. Furthermore the chemical molecule-by-molecule bottom-up approach offers unlimited opportunities for design and construction of nanoscale supramolecular structures, by combining the high precision of the chemical synthesis and scientists with a device driven-ingenuity. Furthermore, because the ability to perform specific functions as a response to external stimuli depends directly on the chemical nature and properties of the component units, in this review, we illustrate some examples of molecular devices and machines based on specific molecular units that have been developed in the research group of one of the authors. They are systems exhibiting pseudorotaxane, rotaxane, catenane and dendrimer structures that incorporate redox- and/or photoactive moieties. Conclusion: The future development of this kind of research will lead to more and more sophisticated artificial molecular devices and machines with better performances regarding their stability, switching, speed, and functions performed. We foresee that they will find useful applications in various fields, like energy conversion, sensoring, catalysis, and will give a great contribution in solving the present-day main problems regarding food, health, energy supply, and environment protection

How the assembly and protection of the bacterial cell envelope depend on cysteine residues.

The cell envelope of Gram-negative bacteria is a multilayered structure essential for bacterial viability; the peptidoglycan cell wall provides shape and osmotic protection to the cell, and the outer membrane serves as a permeability barrier against noxious compounds in the external environment. Assembling the envelope properly and maintaining its integrity is a matter of life and death for bacteria. Our understanding of the mechanisms of envelope assembly and maintenance has increased tremendously over the last two decades. Here, we review the major achievements during this time, giving central stage to the amino acid cysteine, one of the least abundant amino acid residues in proteins, whose unique chemical and physical properties often critically support biological processes. First, we review how cysteines contribute to envelope homeostasis by forming stabilizing disulfides in crucial bacterial assembly factors (LptD, BamA, and FtsN) and stress sensors (RcsF and NlpE). Second, we highlight the emerging role of enzymes that use cysteine residues to catalyze reactions that are necessary for proper envelope assembly, and we also explain how these enzymes are protected from oxidative inactivation. Finally, we suggest future areas of investigation, including a discussion of how cysteine residues could contribute to envelope homeostasis by functioning as redox switches. By highlighting the redox pathways that are active in the envelope of , we provide a timely overview on the assembly of a cellular compartment that is the hallmark of Gram-negative bacteria