1. The u.v.-spectral characteristics of 5,5'-dithiobis-(2-nitrobenzoic acid) (Nbs(2)), 2,2'-dipyridyl disulphide (2-Py-S-S-2-Py), 4,4'-dipyridyl disulphide (4-Py-S-S-4-Py), 5-mercapto-2-nitrobenzoic acid (Nbs), 2-thiopyridone (Py-2-SH) and 4-thiopyridone (Py-4-SH) were determined over a wide range of pH and used to calculate their acid dissociation constants. 2. The reactions of l-cysteine, 2-m...

In this work, antiparasitic peptidomimetics inhibitors (PEP) of falcipain-3 (FP3) Plasmodium falciparum (Pf) are proposed using structure-based and computer-aided molecular design. Beginning with the crystal structure PfFP3-K11017 complex (PDB ID: 3BWK), three-dimensional (3D) models FP3-PEPx complexes known activities () were prepared by in situ modification, based on mechanics implicit solvat...

The electrochemical behavior and the corrosion rate of aluminum electrode have been evaluated in different pH solutions in absence and presence of aggressive anion, using open-circuit potential measurements and potentiodynamic polarization technique. Also, the corrosion inhibiting effects of ortho, meta and para toludine in a solution of pH4 containing 0.1M sodium chloride was investigated usin...

We design here new nanomolar antituberculotics, inhibitors of Mycobacterium tuberculosis thymidine monophosphate kinase (TMPKmt), by means of structure-based molecular design. 3D models of TMPKmt-inhibitor complexes have been prepared from the crystal structure of TMPKmt cocrystallized with the natural substrate deoxythymidine monophosphate (dTMP) (1GSI) for a training set of 15 thymidine analo...

Proton gradients are the endocellular forces required to drive the transport of ions and other microand macromolecules across membranes. In petunia, mutations in ANTHOCYANIN 1, (AN1), AN2, and AN11 and in PH1-PH7 affect the pH of the vacuolar lumen. Because AN1, AN2, AN11 and PH2, PH3, PH4 and PH6 encode regulatory proteins, they are likely to control transcription of genes involved in an unkno...

We studied the effects of acute external acidification on the acid-base status and plasma and red cell ion concentrations of lampreys. Mortality was observed within 24 h at pH5 and especially at pH4. The main reason for the high sensitivity of lampreys to acid water appears to be the large drop in blood pH: 0-6 and 0-8 units after 24 h at pH5 and pH4, respectively. The drop of plasma pH is much...

در صنعت پالایشگاه و پتروشیمی‌ها به دلیل وجود تجهیزات تمام فلزی محیط اسیدی خوردگیتنشی زیاد است با توجه افزایش کاربرد فولادهای زنگ نزن این صنایع پژوهش بررسی اثر ضربات امواج اولتراسونیک بر رفتار خوردگی فولاد 316 (S.S 316) می‌پردازیم. هدف از تأثیر روش تنش‌زدایی برافزایش مقاومت قطعات محیط‌های خورنده است. لازم ذکر که، تنش پسمان نمونه‌ها جوش‌کاری ایجادشده ابتدا نمونه مدنظر استفاده ارتعاش تحت فرکانس 20...

The effect of colonic distension and changes in intraluminal pH and osmolality have been investigated in patients with well established colostomies. Small volumes of acidic buffer (pH4) and hypertonic saline (4%) were found to be only a very weak peristaltic stimulus. Strong hypertonic solutions (glycerine BP) induced a poorly sustained peristaltic response in the majority of cases. Distension ...

1. A Sepharose-(glutathione-2-pyridyl disulphide) conjugate has been prepared. 2. Its use in a new type of chromatography, covalent chromatography by thiol-disulphide interchange, is described. 3. With this technique, papain containing 1 intact catalytic site [thiol with high reactivity towards 2,2'-dipyridyl disulphide (2-Py-S-S-2-Py) at pH4] per mol of protein is readily prepared both from dr...