At Physiological Temperatures the ATPase Rates of Shortening Soleus and Psoas Myofibrils Are Similar

AbstractWe obtained the temperature dependences of the adenosine triphosphatase (ATPase) activities (calcium-activated and relaxed) of myofibrils from a slow muscle, which we compared with those from a fast muscle. We chose rabbit soleus and psoas because their myosin heavy chains are almost pure: isoforms I and IIX, respectively. The Arrhenius plots of the ATPases are linear (4–35°C) with energies of activation for soleus myofibrils 155kJmol−1 (activated) and 78kJmol−1 (relaxed). With psoas myofibrils, the energies of activation were 71kJmol−1 (activated) and 60kJmol−1 (relaxed). When extrapolated to 42°C the ATPase rates of the two types of myofibril were identical: 50s−1 (activated) and 0.23s−1 (relaxed). Whereas with psoas myofibrils the Km for adenosine triphosphate (activated ATPase) is relatively insensitive to temperature, that for soleus myofibrils increased from 0.3μM at 4°C to 66.5μM at 35°C. Our results illustrate the importance of temperature when comparing the mechanochemical coupling in different types of muscle. We discuss the problem of how to reconcile the similarity of the myofibrillar ATPase rates at physiological temperatures with their different mechanical properties

Rescue of Pressure Overload-Induced Heart Failure by Estrogen Therapy.

BackgroundEstrogen pretreatment has been shown to attenuate the development of heart hypertrophy, but it is not known whether estrogen could also rescue heart failure (HF). Furthermore, the heart has all the machinery to locally biosynthesize estrogen via aromatase, but the role of local cardiac estrogen synthesis in HF has not yet been studied. Here we hypothesized that cardiac estrogen is reduced in HF and examined whether exogenous estrogen therapy can rescue HF.Methods and resultsHF was induced by transaortic constriction in mice, and once mice reached an ejection fraction (EF) of ≈35%, they were treated with estrogen for 10 days. Cardiac structure and function, angiogenesis, and fibrosis were assessed, and estrogen was measured in plasma and in heart. Cardiac estrogen concentrations (6.18±1.12 pg/160 mg heart in HF versus 17.79±1.28 pg/mL in control) and aromatase transcripts (0.19±0.04, normalized to control, P<0.05) were significantly reduced in HF. Estrogen therapy increased cardiac estrogen 3-fold and restored aromatase transcripts. Estrogen also rescued HF by restoring ejection fraction to 53.1±1.3% (P<0.001) and improving cardiac hemodynamics both in male and female mice. Estrogen therapy stimulated angiogenesis as capillary density increased from 0.66±0.07 in HF to 2.83±0.14 (P<0.001, normalized to control) and reversed the fibrotic scarring observed in HF (45.5±2.8% in HF versus 5.3±1.0%, P<0.001). Stimulation of angiogenesis by estrogen seems to be one of the key mechanisms, since in the presence of an angiogenesis inhibitor estrogen failed to rescue HF (ejection fraction=29.3±2.1%, P<0.001 versus E2).ConclusionsEstrogen rescues pre-existing HF by restoring cardiac estrogen and aromatase, stimulating angiogenesis, and suppressing fibrosis

Cyanomethylene-bis(phosphonate) as ditopical ligand: stepwise formation of a 2-D heterometallic Fe(III)-Ag(I) coordination network

A new heteroditopic ligand, cyanomethylene-bis(5,5-dimethyl-2-oxo-1,3,2 lambda(5)-dioxa-phosphorinane) 1 (bphosCN), has been reacted with Fe(ClO4)(3) to afford the mononuclear complex Fe(bphosCN)(3) 2 which crystallized in the cubic system, space group Pa (3) over bar. The iron center, chelated by the oxygen atoms of the ligand, shows an almost perfect octahedral geometry, with the CN groups disposed at 120 degrees each other. Further reaction with AgClO4 provided the heterometallic coordination polymer (infinity)(2) {[(Fe (bphosCN)(3))(3)Ag-3(H2O)(2)]center dot(ClO4)(3)} 3 as the unique crystalline polymorph, in the monoclinic space group P21/a. The targeted 2D honeycomb type structure has been achieved through an interplay between coordinative CN-Ag bonds and CN center dot center dot center dot H2O bonds. The magnetic measurements demonstrate the existence of isolated paramagnetic Fe(III) centers in both complexes

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

On the seasonality of waters below the seasonal thermocline in the Gulf of Cádiz

This work examines the seasonal thermohaline variability in the Gulf of Cádiz (SW Iberian Peninsula) based on 2009–2020 repeated hydrographic observations. Subsurface water types are assorted within the mixing triangle formed by Mediterranean and Eastern North Atlantic Central Waters (ENACW). A sharp interface between 400-500 m depth separates the saline Mediterranean Overflow Waters (MOW) from the ENACW salinity minimum siting atop. The water column is warmer and more saline in winter (cooler, fresher in summer). Maximum differences of up to 0.6 ∘C and 0.15 emanate from the ENACW/MOW interface. Changes appear related to the wind-driven seasonal alternation of vertical displacement of isopycnals and poleward-equatorward transports. Upwelling-favorable winds in summer steer positive Ekman pumping velocities, which seem responsible for cooling over the ENACW salinity minimum. Below, the warm, saline signal of subtropical waters from the Azores current is attenuated by the summer approach of cooler, fresher waters from the Portugal Current system. The change of sign of Ekman pumping in winter suggests subsidence of isopycnals and warming/salinification under the seasonal thermocline. Seasonal thermohaline changes of waters leaving the Mediterranean Sea are insufficient to explain the variations under the ENACW/MOW interface. Rather, variability of Atlantic waters entrained by the overflow seem to dictate these differences.Postprint2,08