G2019S LRRK2 mutation in familial and sporadic Parkinson's disease in Russia.

Among mutations associated with autosomal dominant and sporadic Parkinson's disease (PD) the G2019S substitution in the leucine-rich repeat kinase 2 (LRRK2) gene is the most frequently identified. To estimate its frequency in Russia, we analyzed 208 patients with PD from the Northwestern region of Russia. Of these, 51 patients were probands from families with PD compatible with autosomal dominant inheritance. The control group represented 161 subjects without neurological disorders settled in the same region. The frequency of the G2019S mutation was greater in familial PD (2 [3.9%] of 51) than in sporadic PD (1 [0.6%] of 157). In addition, this mutation was found in the proband's father, who also had PD, in 1 PD family, and in 1 carrier without signs of PD at age 40 in another PD family. All carriers were heterozygous for the G2019S mutation and reported the Ashkenazi Jewish origin. The mutation was not found in the control group.     

Photoacoustic and ultrasound imaging using dual contrast perfluorocarbon nanodroplets triggered by laser pulses at 1064 nm

Recently, a dual photoacoustic and ultrasound contrast agent—named photoacoustic nanodroplet—has been introduced. Photoacoustic nanodroplets consist of a perfluorocarbon core, surfactant shell, and encapsulated photoabsorber. Upon pulsed laser irradiation the perfluorocarbon converts to gas, inducing a photoacoustic signal from vaporization and subsequent ultrasound contrast from the resulting gas microbubbles. In this work we synthesize nanodroplets which encapsulate gold nanorods with a peak absorption near 1064 nm. Such nanodroplets are optimal for extended photoacoustic imaging depth and contrast, safety and system cost. We characterized the nanodroplets for optical absorption, image contrast and vaporization threshold. We then imaged the particles in an ex vivo porcine tissue sample, reporting contrast enhancement in a biological environment. These 1064 nm triggerable photoacoustic nanodroplets are a robust biomedical tool to enhance image contrast at clinically relevant depths.OCIS codes: (110.5120) Photoacoustic imaging, (170.7170) Ultrasound, (160.4236) Nanomaterials, (170.3880) Medical and biological imaging, (170.7180) Ultrasound diagnostics     

Staging deep venous thrombosis using ultrasound elasticity imaging: animal model

Deep venous thrombi undergo progressive hardening with age. However, the evolution rate remains poorly characterized by both invasive and noninvasive techniques. In a previous study (Emelianov et al. 2002), we demonstrated the potential of ultrasound elasticity imaging to noninvasively detect and age thrombus using a rat-based model. Knowing that thrombi harden over time is useful, but the value of the technique relies on whether the age of a thrombus can be predicted from strain estimates, and how accurate these predictions are. The objective of the present study is to answer these two questions. In the previous study, thrombus elasticity changes were monitored only on day 3, 6 and 9 after surgically induced formation of thrombosis in rat inferior vena cavas. In this study, ultrasound elasticity imaging was performed on two independent groups of rats (16 in total) starting from day 3 through day 10 with more temporal samples through the thrombus maturation process. For each rat, thrombus hardness was quantified at each scan interval by measures of normalized strains and reconstructed relative Young's moduli. In both groups, strain magnitudes exhibit progressive decrease as clots age. The relationship between the normalized strain and the clot age was developed from the first group and evaluated by the second group. Statistical analysis showed that the age estimation accuracy is within 0.8 day. If further research can successfully transfer the animal clot-hardening model to human patients, we believe that elasticity imaging will become a key component of venous compression ultrasound for effective diagnosis and treatment of deep venous thrombosis.     

Effect of prolactin and dopaminergic drugs on uterine response to chronic estrogen exposure.

The aim of this work was to examine the role of prolactin and dopaminergic drugs, which affect prolactin secretion, on proliferative and morphogenetic reactions in the uterus under continuous estrogen treatment. Ovariectomized mice received injections of estradiol dipropionate (2 microg per 100 g, weekly) or vehicle and daily injections of prolactin (0.25 mg/100 g) or saline (0.05 ml) for 30 days. Other groups of mice received injections of estradiol or vehicle and injections of saline, and were allowed to drink bromocriptine (25 mg/l), metoclopramide (25 mg/l), or only tap water for 30 days. Prolactin administration results in a decrease in the incidence of abnormal glands with abnormal epithelium, the incidence of atypical hyperplasia, uterine weight, proliferation (the number of mitotic and bromodeoxyuridine-labeled cells) and the levels of estrogen receptor-alpha, but causes an increase in the level of beta-catenin in uterine tissues of estrogen-treated mice. The effect of metoclopramide, which increases prolactin secretion, is principally similar to prolactin, but much less expressed. Bromocriptine, which reduces prolactin levels, increases uterine weight, proliferation, the levels of estrogen receptor-alpha, the incidence of abnormal glands with abnormal epithelium, the incidence of complex and atypical hyperplasia, and decreases the level of beta-catenin in uterine structures of estrogen-treated mice. In the absence of estradiol, none of the treatments used had any effect on the parameters tested. Thus, prolactin or metoclopramide produce antiestrogenic effects in the uterus of mice and prevent the formation of atypical hyperplasia which has an unfavorable prognosis, but bromocriptine has the opposite effect. Estrogen receptor-alpha and beta-catenin were associated with the actions of prolactin, metoclopramide and bromocriptine on estrogen-dependent processes in the uterus.     

Effect of hydrocortisone on sodium and potassium distribution in the sections of the cerebral cortex of rats after their electric stimulation]

Sections of the rat brain cortex were incubated in various physiological media using container-electrodes, similar to the McIlwain's type. The shifts of sodium and potassium distribution between the extra- and intracellular spaces of the slices after different stimulation parameters and the subsequent restoration were measured. The administration of hydrocortisone (for 7 days, 5 mg/100 g daily) usually increased the response of the slices to the stimulation in incubation in the glutamate devoid medium. When 0.2--0.5 mM of glutamate was added to the media the effect of hydrocortisone disappeared. Possible physiological significance of the mentioned results is discussed.     

Multiplex photoacoustic molecular imaging using targeted silica-coated gold nanorods

The establishment of multiplex photoacoustic molecular imaging to characterize heterogeneous tissues requires the use of a tunable, thermally stable contrast agent targeted to specific cell types. We have developed a multiplex photoacoustic imaging technique which uses targeted silica-coated gold nanorods to distinguish cell inclusions in vitro. This paper describes the use of tunable targeted silica-coated gold nanorods (SiO(2)-AuNRs) as contrast agents for photoacoustic molecular imaging. SiO(2)-AuNRs with peak absorption wavelengths of 780 nm and 830 nm were targeted to cells expressing different cell receptors. Cells were incubated with the targeted SiO(2)-AuNRs, incorporated in a tissue phantom, and imaged using multiwavelength photoacoustic imaging. We used photoacoustic imaging and statistical correlation analysis to distinguish between the unique cell inclusions within the tissue phantom.