Observation of Single-Mode, Kelvin-Helmholtz Instability in a Supersonic Flow.

We report the first observation, in a supersonic flow, of the evolution of the Kelvin-Helmholtz instability from a single-mode initial condition. To obtain these data, we used a novel experimental system to produce a steady shock wave of unprecedented duration in a laser-driven experiment. The shocked, flowing material creates a shear layer between two plasmas at high energy density. We measured the resulting interface structure using radiography. Hydrodynamic simulations reproduce the large-scale structures very well and the medium-scale structures fairly well, and imply that we observed the expected reduction in growth rate for supersonic shear flow.

HOW EXPRESSIONS OF CLAUDIN-1 AND MMP-2 IN RETINOBLASTOMA CORRELATE WITH HISTOLOGICAL DIFFERENTIATION AND OPTIC NERVE INVASION.

Retinoblastoma is a commonly seen and dangerous intraocular malignant tumor in infants. Studies have found that Claudin-1 and MMP-2, whose expressions may be connected, play roles in tissues of retinoblastoma. In this study we analyze and discuss changes of Claudin-1 and MMP-2 expressions, and the correlation between the expressions and retinoblastoma histological differentiation and optic nerve invasion. MaxVisionTM was applied to detect expressions of Claudin-1 and MMP-2 in 45 samples of retinoblastoma and 15 paraffin-embedded samples of normal retina. The correlation between Claudin-1 expression and MMP-2 expression was analyzed based on chi-squared test and Spearman’s correlation test. Positive expressions of Claudin-1 in retinoblastoma were fewer than those in retina; higher positive expressions were found in differentiated tissues than in undifferentiated tissues; while compared to expressions in invasive optic nerves, Claudin-1 expressed more positively in optic nerves without invasion. As for MMP-2, its expressions were higher in retinoblastoma than in normal retina; undifferentiated tissues had higher positive expressions than differentiated tissues, which were not statistically significant; higher positive expressions were detected in invasive optic nerves. Thus, it could be concluded that the correlation between Claudin-1 expression and MMP-2 expression in retinoblastoma was negative. Expressions of Claudin-1 were positively related to histological differentiation and optic nerve invasion of retinoblastoma; while MMp-2 expression had negative correlation with histological differentiation and optic nerve invasion of retinoblastoma. Claudin-1 and MMP-2 played a negative role in the optic nerve invasion and tumor development of retinoblastoma.

How high energy fluxes may affect Rayleigh-Taylor instability growth in young supernova remnants.

Energy-transport effects can alter the structure that develops as a supernova evolves into a supernova remnant. The Rayleigh-Taylor instability is thought to produce structure at the interface between the stellar ejecta and the circumstellar matter, based on simple models and hydrodynamic simulations. Here we report experimental results from the National Ignition Facility to explore how large energy fluxes, which are present in supernovae, affect this structure. We observed a reduction in Rayleigh-Taylor growth. In analyzing the comparison with supernova SN1993J, a Type II supernova, we found that the energy fluxes produced by heat conduction appear to be larger than the radiative energy fluxes, and large enough to have dramatic consequences. No reported astrophysical simulations have included radiation and heat conduction self-consistently in modeling supernova remnants and these dynamics should be noted in the understanding of young supernova remnants.

Existence of a gonadotropin-releasing hormone-like factor in the grass shrimp (black tiger prawn, Penaeus monodon)

The immunological and biological gonadotropin-releasing hormone (GnRH)-like activities in the acid extract of shrimp hepatopancreas (SHE) were studied. The immunological activity determined by a GnRH radioimmunoassay was 22.3 +/- 2.7 ng per ml of SHE. SHE increased luteinizing hormone (LH) release from rat anterior pituitary glands (APs) in vitro, and its biological activity was 42.9 +/- 28.5 ng per ml. No immunological activity was found in the acid extracts of eye ball, eye stalk, nerve and heart. These results suggest that the shrimp hepatopancreas has both immunological and biological GnRH-like activity.

The presence of a thyrotropin-releasing hormone-like factor in the grass shrimp (black tiger prawn, Penaeus monodon)

Immunoreactive (TRH) has been detected in acid and methanol extracts of hepatopancreas, in grass shrimp (black tiger prawn, Penaeus monodon). The evidence provided by the stimulation of thyrotropin (TSH) release from perfused rat anterior pituitary glands in vitro following the application of hepatopancreas extracts (SHE) reflected the presence of TRH-like substance in the shrimp. However, the molecular weight of the TRH-like substance estimated by gel filtration in SHE was greater than that of the synthetic TRH. Furthermore, other differences are also noted, e.g. TRH-like activity in SHE could not be completely neutralized by anti-TRH antiserum nor degraded in normal rat serum.

Glandular odontogenic cyst: a case report.

Glandular odontogenic cyst (GOC) is an extremely rare lesion occurring in the jawbones. Sialo-odontogenic cyst was first described as a multicystic lesion resembling a botryoid odontogenic cyst (BOC) or a central mucoepidermoid carcinoma by Padayachee in 1987. In 1988, Gardner used the term "glandular odontogenic cyst" and considered it as a histologic variant of BOC. Most authors agreed that GOC was odontogenic because of the concurrent ball-like epithelial structure, ameloblastoma, squamous odontogenic tumor-like proliferation in its wall, or hyaline bodies in the epithelium lining. Recently, immunohistochemical studies of the cytokeratin profiles have also supported this concept. Its aggressive behavior and the recurrent tendency make it important. A new case of GOC in a 59-year-old male presented as a multilocular radiolucency in the anterior region of the mandible, invading the marrow space by epithelial islands is described with other clinicopathologic features and the literature is briefly discussed.

Demonstration of x-ray fluorescence imaging of a high-energy-density plasma.

Experiments at the Trident Laser Facility have successfully demonstrated the use of x-ray fluorescence imaging (XRFI) to diagnose shocked carbonized resorcinol formaldehyde (CRF) foams doped with Ti. One laser beam created a shock wave in the doped foam. A second laser beam produced a flux of vanadium He-α x-rays, which in turn induced Ti K-shell fluorescence within the foam. Spectrally resolved 1D imaging of the x-ray fluorescence provided shock location and compression measurements. Additionally, experiments using a collimator demonstrated that one can probe specific regions within a target. These results show that XRFI is a capable alternative to path-integrated measurements for diagnosing hydrodynamic experiments at high energy density.

Pattern of reproductive hormone secretion and disappearance rates of LH and FSH in senile male rats.

Old Long-Evans male rats (24-33 months of age) do show postcastration rise in serum LH but do not have postcastration LH rise in the pituitary both as expressed in content and concentration. The serum LH levels of intact and castrated rats of old age show a tendency of decrease, though not to the level of statistical significance. The pituitary FSH content and concentration of intact old rats are not different from those of young adults (3.5-5 months of age), whereas serum FSH level of intact old male rats is significantly higher than that of intact young adults. There is a postcastration rise in the pituitary FSH content as well as concentration and serum FSH level in both age-groups. The half-lives of endogenous and exogenous LH and FSH are not different between old male rats (24- to 31-month-old) and young adults (3- to 5-month-old). Blood testosterone levels begin to decline between the age of 12 and 18 months and remained low from 18 months of age on. These results indicate: (1) deficiencies in the LH regulatory mechanism in response to removal of gonadal steroids are easier to manifest than those of FSH control mechanism in old age in male rats; (2) the ability of clearing circulating LH and FSH of old male rats is not different from that o young adult males, if their molecular sizes are similar, and (3) high serum FSH level of old male rats is not due to prolonged half-life in the circulation.

Simulatory hypothyroidism pituitary function in vitro: dynamics of TSH release after TRH stimulation in perifused rat hemipituitaries.

The production of immunoreactive TSH by hemipituitaries (Hps) to the stimulation of TRH in perifusion with negligible influence of the feedback of secretogogues and hormones was analysed. The stimulations were of long term continuous (3 hrs) and short term (15 min), with the dose levels of 1, 10 and 100 ng per ml of medium (for 3 hrs) or in 2 ml (for 15 min). The largest amount in production and the fastest rate in release of TSH found in present report is at 10 ng level. Only total TSH, in tissue plus in medium, after continuous TRH stimulation were dose-related, but not in release alone. We present herein an analysis of pituitary TSH production, in a perifusion system under steady TRH stimulation. This arrangement is believed to be a condition simulating hypothyroidism in pituitary level and suitable for study of the functions of the pituitary with hyperactivated thyrotrophs.