Homeostasis

Homeostasi

Comparative Study of Single-Stage and Two-Stage Coagulation

W pracy porównano skuteczność tradycyjnie stosowanej koagulacji jednostopniowej i koagulacji dwustopniowej, w której całkowita dawka koagulantu została podzielona i została wprowadzona do oczyszczanej wody w dwóch kolejnych etapach rozdzielonych sedymentacją międzystopniową. W badaniach określono możliwość zmniejszenia dawki koagulantu w wyniku zastosowania koagulacji dwustopniowej oraz wpływ czasu sedymentacji międzystopniowej na skuteczność procesu. Przedmiotem badań były roztwory modelowe przygotowane na bazie wody wodociągowej. Koagulacja prowadzona była siarczanem glinu (ALS) oraz wstępnie zhydrolizowanym chlorkiem poliglinu (PAX-XL9). Wykazano, że zastosowanie koagulacji dwustopniowej pozwoliło obniżyć wymaganą dawkę koagulantów. Większy stopień zmniejszenia dawki uzyskano dla koagulantu PAX-XL9. Nawet przy zastosowaniu takiej samej dawki koagulantu jak w procesie jednostopniowym, wzrost agresywności korozyjnej wody po koagulacji dwustopniowej był mniejszy. Wpływ czasu sedymentacji międzystopniowej na efektywność procesu był zdecydowanie mniejszy, niż dawki koagulantów. Większe koszty inwestycyjne wynikające z zastosowania koagulacji dwustopniowej może zrekompensować mniejsze zużycie koagulantów oraz reagentów stosowanych do stabilizacji wody.The efficiency of the conventional single-stage coagulation was compared with that of the two-stage coagulation where the overall coagulant dose was divided and injected into the water during two stages separated by the sedimentation process. The possibility of reducing the coagulant dose due to the application of the two-stage process was examined and the problem of how the duration of the sedimentation process might affect the extent of coagulation was analyzed. The experiments were carried out with model solutions prepared on the basis of tap water, with alum and prehydrolyzed (poly)aluminium chloride (PAX-XL9) as coagulants. The study produced the following findings: the two-stage coagulation process enabled the required coagulant dose to be reduced; the reduction was greater with the PAX-XL9 than with the alum dose; even if the coagulant dose used was that for the single-stage coagulation, the two-stage process was concomitant with a lower rise in water corrosivity; the effect of sedimentation time on the extent of coagulation was far less distinct than the effect of coagulant dose. Although two-stage coagulation involves a higher capital cost, this is compensated by the reduced use of coagulants and water-stabilizing chemicals

Indications and contraindications for shock wave lithotripsy and how to improve outcomes

For over 35 years shock wave lithotripsy has proven to be an effective, safe and truly minimally invasive option for the treatment of nephrolithiasis. Various technical factors as well as patient selection can impact the success of the procedure. We used published work focusing on outcomes of shock wave lithotripsy, risk of complications, and strategies for improving stone fragmentation to create this review. Multiple patient and technical factors have been found to impact success of treatment. Skin to stone distance, stone density and composition, size and location of the stone within the urinary system all influence stone free rates. A slower rate with a gradual increasing voltage, precise targeting, proper coupling will improve stone fragmentation and decrease risk of complications. The selection of appropriate patients through a shared decision making process and attention to the technical factors that improve stone free rates is key to providing an effective treatment and patient satisfaction. Keywords: Kidney calculi, Nephrolithiasis, Urolithiasis, Extracorporeal shock wave therapy, Lithotrips

Caspases and cancer : Mechanisms of inactivation and new treatment modalities

Elimination of superfluous or mutated somatic cells is provided by various mechanisms including apoptosis. Deregulation of apoptotic signaling pathways may contribute to oncogenesis. Aspartate specific cysteine proteases, termed caspases are the key effector molecules in apoptosis. The aim of this review is to summarize the various defects in caspase-dependent cell death machinery identified in the neoplastic cells. These include not only mutations, but also alterations of gene methylation, and altered mRNA stability. Among the molecules that we discuss are elements of the extrinsic death pathway like CD95 (APO-1/Fas), FADD, FLIPs, FLICE, other apical caspases, components of the intrinsic apoptotic pathway like Apaf-1, caspase-9, and modulators of apoptotic pathways like IAPs, Smac/DIABLO, OMI/HtrA2, and other apoptosis regulating proteins. We also discuss recent data on cancer-specific agents that target effector mechanisms of apoptosis. Particular emphasis is given to the prospects for combining cell suicide-activating approaches with classical cancer therapies

Akt is transferred to the nucleus of cells treated with apoptin, and it participates in apoptin-induced cell death

Abstract. Objectives: The phosphatidylinositol 3-kinase (PI3-K)/Akt pathway is well known for the regulation of cell survival, proliferation, and some metabolic routes. Meterials and Methods: In this study, we document a novel role for the PI3-K/Akt pathway during cell death induced by apoptin, a tumour-selective inducer of apoptosis. Results: We show for the first time that apoptin interacts with the p85 regulatory subunit, leading to constitutive activation of PI3-K. The inhibition of PI3-K activation either by chemical inhibitors or by genetic approaches severely impairs cell death induced by apoptin. Downstream of PI3-K, Akt is activated and translocated to the nucleus together with apoptin. Direct interaction between apoptin and Akt is documented. Co-expression of nuclear Akt significantly potentiates cell death induced by apoptin. Thus, apoptin-facilitated nuclear Akt, in contrast to when in its cytoplasmic pool, appears to be a positive regulator, rather than repressor of apoptosis. Conclusions: Our observations indicate that PI3-K/Akt pathways have a dual role in both survival and cell death processes depending on the stimulus. Nuclear Akt acts as apoptosis stimulator rather than as a repressor, as it likely gains access to a new set of substrates in the nucleus. The implicated link between survival and cell death pathways during apoptosis opens new pharmacological opportunities to modulate apoptosis in cancer, for example through the manipulation of Akt's cellular localization

Correction of Writing disorders of the 1st year pupils with Phonetically Phonemic Disorders

Abstract. Objectives: The phosphatidylinositol 3-kinase (PI3-K)/Akt pathway is well known for the regulation of cell survival, proliferation, and some metabolic routes. Meterials and Methods: In this study, we document a novel role for the PI3-K/Akt pathway during cell death induced by apoptin, a tumour-selective inducer of apoptosis. Results: We show for the first time that apoptin interacts with the p85 regulatory subunit, leading to constitutive activation of PI3-K. The inhibition of PI3-K activation either by chemical inhibitors or by genetic approaches severely impairs cell death induced by apoptin. Downstream of PI3-K, Akt is activated and translocated to the nucleus together with apoptin. Direct interaction between apoptin and Akt is documented. Co-expression of nuclear Akt significantly potentiates cell death induced by apoptin. Thus, apoptin-facilitated nuclear Akt, in contrast to when in its cytoplasmic pool, appears to be a positive regulator, rather than repressor of apoptosis. Conclusions: Our observations indicate that PI3-K/Akt pathways have a dual role in both survival and cell death processes depending on the stimulus. Nuclear Akt acts as apoptosis stimulator rather than as a repressor, as it likely gains access to a new set of substrates in the nucleus. The implicated link between survival and cell death pathways during apoptosis opens new pharmacological opportunities to modulate apoptosis in cancer, for example through the manipulation of Akt's cellular localization

Same session bilateral ureteroscopy for multiple stones: results from the CROES URS Global Study

Purpose: This study presents a comparison of the international experience with ipsilateral and bilateral ureteroscopy for multiple, bilateral ureteral and renal stones vs single stone treatment. Patient and treatment characteristics and outcomes were compared. Materials and Methods: The CROES (Clinical Research Office of the Endourological Society) Ureteroscopy Global Study includes 114 centers in 32 countries. Patients undergoing bilateral ureteroscopy, ipsilateral ureteroscopy for multiple stones and ureteroscopy for a single stone were examined from January 2010 to October 2012. Intraoperative characteristics and postoperative outcomes were identified for each patient. Inverse probability weighted regression adjustment analyses were done to compare outcomes independent of differences among centers and patient characteristics. Results: The CROES Ureteroscopy Global Study consists of 11,885 patients. A total of 2,153 patients (18.7%) were treated for multiple stones, of whom 1,880 (87.3%) and 273 (12.7%) underwent ipsilateral and bilateral ureteroscopy, respectively. Inverse probability weighted regression adjustment models for bilateral vs ipsilateral ureteroscopy and multiple vs single stone treatments showed that patients with bilateral ureteroscopy and multiple stone treatments had lower stone-free rates, higher re-treatment rates and longer operative times compared to patients who underwent ipsilateral ureteroscopy and single stone treatment. There was no difference in complication rates among bilateral, ipsilateral and single stone ureteroscopy. Conclusions: This study presents a large series of patients who underwent bilateral and ipsilateral ureteroscopy. Our findings suggest a decrease in stone-free rates, increased re-treatment rates, increased operative times and longer hospital stay in patients treated for multiple stones. The treatment of multiple stones and bilateral ureteroscopy are safe compared to single stone treatment and ipsilateral ureteroscopy, respectively.Boston Scientifi