Efficiency of placental three dimentional power Doppler ultrasonography for predicting preeclampsia in early pregnancy

Purpose

to evaluate the role of three dimentional power doppler ultrasonography (3D PDUS) of the uteroplacental circulation in early pregnancy as a screening tool for prediction of preeclampsia.

Effects of tanshinone VI on phosphorylation of ERK and Akt in isolated cardiomyocytes and cardiac fibroblasts

Effects of tanshinone VI, a diterpene from Tan-Shen, on humoral factor-induced phosphorylation of ERK and Akt during hypertrophy of cardiomyocytes and fibrosis of cardiac fibroblasts isolated from neonatal rats were examined. Treatment of cultured cardiomyocytes with 10 nM insulin-like growth factor-1 (IGF-1) or 10 nM endothelin-1 resulted in an increase in leucine incorporation into acid-insoluble fraction. Treatment of cultured cardiac fibroblasts with 10 nM IGF-1 or 10 nM angiotensin II increased incorporation of proline. IGF-1 increased phosphorylated extracellular signal-regulated kinase (pERK) and protein kinase B (pAkt) of cardiomyocytes, whereas endothelin-1 increased pERK, but not pAkt. Treatment of cardiac fibroblasts with 10 nM IGF-1 or 10 nM angiotensin II also increased pERK, whereas pAkt was increased by treatment with IGF-1 alone. When the cardiomyocytes were incubated in the presence of 10 μM tanshinone VI, IGF-1- and endothelin-1-induced increases in pERK, but not pAkt, were partially attenuated. Treatment of cardiac fibroblasts with 10 μM tanshinone VI also attenuated IGF-1-induced increases in pERK and pAkt. Tanshinone VI also partially attenuated angiotensin II-induced increase in proline incorporation into cardiac fibroblasts. PD98059, an inhibitor for phosphorylation of extracellular signal-regulated kinase (ERK), but not wortmannin, that for protein kinase B phosphorylation, attenuated an increase in leucine incorporation into cardiomyocytes in the presence of either IGF-1 or endothelin-1. These results suggest that tanshinone VI is a possible agent that can attenuate the humoral factor-induced hypertrophy of cardiomyocytes and fibrosis of cardiac fibroblasts via an attenuation of ERK phosphorylation in these cells.     

Structural features of thePip/AzPip couple in the crystalline state: influence of the relative AzPip location in an azadipeptide sequence upon the induced chirality and conformational characteristics

Abstract: Azapipecolic (AzPip) is a pipecolic (Pip) residue analogue containing a nitrogen atom in place of the C^αH group. AzPip was introduced into two reverse dipeptide sequences,Piv‐AzPip‐l ‐Ala‐NHiPr I and Boc‐l ‐Ala‐AzPip‐NHiPr II in order to evaluate, in the crystalline state, the influence of thel ‐Ala‐induced chirality upon the prochiral AzPip residue, and therefore the resulting conformational characteristics, according to the relative position of the AzPip residue. Piv‐dl ‐Pip‐NHMe III served as a control derivative for comparison between the properties of the two different heterocycles of Pip and AzPip residues. Piperidine and hexahydropyridazine rings have a few characteristics in common: chair conformation, axial disposition of the C‐terminal backbone substituent and the cisoid form of the N‐terminal tertiary amide function. An almost pure sp³ hybridization state is observed for the substituted nitrogen atom N^α, so that l ‐Ala induces an AzPip (R) or (S) chirality when it follows or precedes, respectively, the azaresidue in such a pseudodipeptide sequence. If both I and II compounds present a short NH…N contact between the sp² tertiary amide nitrogen atom and the NH of the next secondary amide function, whatever the chiral nature of the sequence, the heterochiral azadipeptide I adopts a rather totally extended conformation while the homochiral azadipeptide II is folded by a β‐VI turn‐like structure stabilized by a classical 4→1 intramolecular hydrogen bond.     

Fixed-Bed Modification of Zeolitic Tuffs and Their Application for Cr(VI) Removal

Natural clinoptilolite tuff (CL) and chabazite-clinoptilolite tuff (CH) were modified in fixed-bed column by immobilization of hexadecyltrimethylammonium bromide (HDTMA-Br), then investigated as a sorbent for inorganic anions of Cr(VI). The proposed modification technique combined with surfactant solution batching allows minimizing the surfactant loses through foaming and crystallization and creation of stable organic coverage. The HDTMA loading depended on the mineral composition of the zeolitic tuff, the topology of its external surface, and process conditions. The maximum surface coverage was obtained by gradually dosing surfactant solution in the smallest volume of batches and corresponded up to 100% and 182% of external cation exchange capacity (ECEC) for mono and double layer coverage, respectively. In case of mono layer coverage, modification proceeds until the exhaustion of surfactant in supply solution, while in the double layer one, until equilibrium of HDTMA concentration in both zeolitic and liquid phases was established. The efficiency of Cr(VI) uptake by prepared surface modified zeolites (SMZs) increased with increasing of HDTMA loading. In the case of mono layer SMZs, the capacities of CH-HDTMA and CL-HDTMA were 10.3 and 5.4 mg/g, respectively, while in the case of double layer SMZs, the amount of Cr uptake on CH-HDTMA and CL-HDTMA were 16.8 and 15 mg/g, respectively. Ion exchange is the predominant mechanism of Cr(VI) sorption but it takes place only if modification resulted in at least partial double layer coverage. The XPS analysis reveals Cr(VI) reduction to a less-toxic Cr(III) by the electron donating N-containing groups and by reaction with Fe⁺² ions on the zeolite external surface.     

Sibs affected with both Ehlers-Danlos syndrome type VI and cystic fibrosis

We report on the unprecedented combination of two recessively inherited disorders, the kyphoscoliosis type of Ehlers-Danlos syndrome (EDS type VI) and cystic fibrosis (CF), in two sibs born to consanguineous Turkish parents. Because of failure to thrive and bronchitis CF was diagnosed in the index patient early whereas EDS VI was recognized only very late. Both patients had marked muscular hypotonia at birth, delayed gross motor development, progressive kyphoscoliosis, joint dislocations, Marfanoid habitus, hypertrophic and atrophic scars, and osteopenia. EDS VI was proven by collagen studies and the pathognomonic pattern of urinary pyridinolines. Because the genes coding for the two disorders are located on different chromosomes and a chromosomal rearrangement was excluded, we conclude that their combination is a chance association. The cardiopulmonary impairment common to both diseases makes the prognosis dismal. Am. J. Med. Genet. 78: 455–460, 1998. © 1998 Wiley-Liss, Inc.     

GPVI modulation during platelet activation and storage: its expression levels and ectodomain shedding compared to markers of platelet storage lesion

Platelet storage is associated with deleterious changes leading to the loss of platelet reactivity and response. During storage, platelets experience increased expression and shedding of P-selectin and CD40L as specific markers of platelet activation, whereas GPIbα decreases due to ectodomain shedding. As an important adhesive receptor, GPVI contributes significantly to thrombus formation while its expression and shedding levels during storage of platelet products have not been well characterized yet. This study investigated the modulation of GPVI during platelet storage.

For this study, samples obtained from 10 PRP-platelet concentrates (PCs) were subjected to flow-cytometry analysis to examine the expression of platelet activation markers and GPVI on days 1, 3, and 5 post-storage. To examine the levels of etcodomain shedding of these molecules, microparticle (MP)-free supernatants were also analyzed by either ELISA or Western blot methods.

According to results, the expression levels of P-selectin and CD40L as well as the amounts of their soluble forms significantly increased during storage. The expression of GPIbα and GPVI decreased whereas their shedding significantly increased post-storage. The expression and shedding levels of these two receptors were significantly correlated. Negative correlations between the expressions of GPIbα or GPVI and P-selectin have been observed whereas their shedding levels were significantly relevant together. In a control study, the use of biotinylated platelet resuspended in Tyrode’s buffer in the presence of ionophore with/without EDTA, confirmed the role of calcium in receptors shedding. In citrated PRP-PCs, recalcification of platelets also enhanced shedding levels of both GPIbα and GPVI. Intriguingly, the shedding levels of GPVI in stored PRP-PCs were much higher than those of ionophore-treated controls obtained from washed platelets. The ratios of sGPVI in stored platelet to ionophore-treated controls were also at least six times higher than those of GPIbα during storage. In conclusion, here we showed significant decreases of GPVI expression associated with its increasing levels of shedding during storage, suggesting GPVI as a valid marker of platelet storage lesion. Importantly, we found higher levels of GPVI shedding in stored platelets than those of ionophore-treated non-stored control samples. This suggests whereas platelet receptor shedding is mainly modulated by calcium-dependent signals, either platelet–surface interactions with the container walls during storage or induced shear stress under long-term agitation, might be also involved in the excessive shedding of GPVI during the storage of PCs.