Specific hybrid liposomes composed of phosphatidylcholine and polyoxyethylenealkyl ether with markedly enhanced inhibitory effects on the growth of tumor cells in vitro

The hybrid liposomes (90mol% DMPC/10mol% C12(EO)8 and 90mol% DMPC/10mol% C12(EO)12) have a highly inhibitory action against the growth of tumor cells. The uniform and stable structure of the hybrid liposomes was revealed on the basis of electron microscopy and dynamic light scattering measurements.     

Pharmacology of the GABA receptor functions in the central nervous systems

gamma-Aminobutyric acid (GABA) is a major inhibitory neurotransmitter in the central nervous system. GABA receptors have been classified into at least two categories, GABA(A) receptors, which are heterogeneous multimeric ligand-gated Cl channels, and GABA(B) receptors, which are coupled to G-proteins. GABA(B) receptors have not only a physiological role in synaptic transmission, but also are important in pathological conditions associated with absence epilepsy, cognitive disorders and nociception. This review describes our current knowledge of the neuropharmacology and neurochemistry of GABA(B) receptors, including their heterogeneity as well as the therapeutic potential of the drugs which interact with these sites.     

Production of macrocyclic ellagitannin oligomers by Oenothera laciniata callus cultures

Melanocyte-stimulating hormone (MSH) has been reported to enhance the experimental metastatic behaviour of melanoma cells in the mouse model. alpha-MSH production and MSH receptor (melanocortin 1 receptor gene) expression have been detected in cultured normal human melanocytes and metastasized melanomas. The exact role of MSH in the metastatic behaviour of human melanoma cells is, however, not yet known. To clarify a possible role of proopiomelanocortin (POMC)-derived peptides, including alpha-MSH, in melanoma development and progression, we analysed immunohistochemically the localization of alpha-MSH adrenocorticotrophic hormone (ACTH) and beta-endorphin in various kinds of benign pigmented naevocytic lesions and malignant melanomas. Three of 21 samples of common and dysplastic naevi showed detectable alpha-MSH staining in naevus cells, and five and six of 15 samples were weakly positive for ACTH and beta-endorphin staining, respectively. In melanoma samples, 24 of 45, 23 of 39 and 30 of 42 samples showed positive staining with alpha-MSH, ACTH and beta-endorphin antibodies, respectively. Furthermore, staining for all three antibodies was noted to be more intense and diffuse in samples of nodular melanoma, vertically growing acral lentiginous melanoma and superficial spreading melanoma as well as metastatic lesions compared with those of naevi. Although it is yet to be determined whether or not this strong staining for POMC-derived peptides in advanced melanoma cells indicates a role of autocrine or paracrine regulation, our results suggest a possible involvement of POMC gene products in melanoma progression.     

Angiomyolipoma of the lung

Extrarenal angiomyolipomas are rare tumors that have been reported in several organs, including the liver, reproductive organs, skin, and retroperitoneum. In this report, we present the clinicopathologic findings of an angiomyolipoma of the lung in a 67-year-old man with no history of tuberous sclerosis or lymphangioleiomyomatosis. To our knowledge, this is the second reported case of pulmonary angiomyolipoma. The tumor was coincidentally found in the left lower lung in association with a hemothorax. Our case was histologically identical to angiomyolipoma occurring in the kidney, but immunohistologic staining for HMB-45 was negative, similar to the first reported case.     

Bilateral pheochromocytomas with von Hippel-Lindau's disease: a case report

A case of bilateral pheochromocytomas with von Hippel-Lindau's disease (VHL) is reported. A 46-year-old woman who had hyperglycemia was admitted to our hospital because of abdominal tumors. Her elder sister and niece had been diagnosed as VHL. Ultrasonography, CT, and MRI revealed bilateral adrenal tumors. Noradrenaline levels in serum and urine were elevated and 131I-MIBG scintigraphy showed accumulation in bilateral adrenal glands. Moreover, she had bilateral renal cysts and cerebellar hemangioblastoma. Bilateral adrenalectomies were performed and pathological diagnosis was pheochromocytoma. This is the seventh case of bilateral pheochromocytomas with VHL reported in Japan.     

Electroluminescence of InAlAs/InGaAs HEMTs lattice-matched to InPsubstrates

Electroluminescence (EL) due to the electron-hole recombination in the channel of InAlAs/InGaAs HEMTs lattice-matched to InP substrates has been measured at room temperature. The carrier temperature extracted from the obtained spectra has been found to be approximately 300 K. It has also been found that the EL comes from a region between the source and the gate by measuring its spatial distribution. These two features imply that holes generated at the drain edge in the channel due to the impact ionization pile up and recombine with the majority electrons between the source and the gate, and agree with results of theoretical analysis     

Liquid-Solid mass transfer in a slurry bubble column and a gas-liquid-solid three-phase fluidized bed

Mass transfer coefficients between particles and liquids in a slurry bubble column and a three-phase fluidized bed containing small size particles were obtained with two mass transfer systems: (1) K⁺ –Na⁺ ion-exchange in cation-exchange resin bead beds, including anion-exchange resin beads as inert particles; (2) zinc dissolution by HCl in zinc-plated glass bead beds, and in beds of non-plated glass beads. Operating parameters were gas velocity, liquid velocity, particle diameter, and particle concentration. The dependence of mass transfer coefficients on these parameters is discussed from the viewpoint of the energy supplied into the systems. Correlations of the experimental data using dimensionless groups are compared to previous correlations.     

Astrocytes containing amyloid beta-protein (Abeta)-positive granules are associated with Abeta40-positive diffuse plaques in the aged human brain

Amyloid beta-protein (Abeta) is the major component of senile plaques that emerge in the cortex during aging and appear most abundantly in Alzheimer's disease. In the course of our immunocytochemical study on a large number of autopsy cases, we noticed, in many aged nondemented cases, the presence of unique diffuse plaques in the cortex distinct from ordinary diffuse plaques by immunocytochemistry. The former were amorphous, very faintly Abeta-immunoreactive plaques resembling diffuse plaques, but they stained for Abeta40 and were associated with small cells containing Abeta-positive granules. A panel of amino- and carboxyl-terminal-specific Abeta antibodies showed that such Abeta40-positive diffuse plaques and cell-associated granules were composed exclusively of amino-terminally deleted Abeta terminating at Abeta40, -42, and -43. Double immunostaining also showed that those Abeta-immunoreactive granules are located in astrocytes and not in microglia or neurons. Immunoelectron microscopy revealed that nonfibrillar Abeta immunoreactivity was located within lipofuscin-like granules in somewhat swollen astrocytes. These findings raise the possibility that astrocytes take up Abeta and attempt to degrade it in lysosomes in the aged brain.     

Inflammatory cytokine production in whole blood modified by liposome-encapsulated hemoglobin

The effect of Neo Red Cells (NRC), liposome-encapsulated hemoglobin, on production of tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) were studied in whole blood preparations ex vivo. Venous blood was collected with heparin and incubated in a CO2 incubator. Treatment of blood samples with NRC reduced the constitutive levels of TNF-alpha and IL-6. Lipopolysaccharide (LPS) treatment for 24 h increased production of TNF-alpha and IL-6 in a dose-dependent manner. Pretreatment with NRC (5%) for 24 h markedly potentiated the LPS-induced TNF-alpha production and, that of IL-6 to a lesser extent. Northern blotting analysis of total RNA in whole blood showed that pretreatment with NRC caused a marked increase in TNF-alpha mRNA expression in response to LPS. It is concluded that NRC potentiates LPS-induced TNF-alpha and IL-6 production in whole blood ex vivo, and that the potentiating effect of NRC on LPS-induced TNF-alpha production can be attributed, at least in part, to an increase in its mRNA expression.     

Left ventricular diastolic properties of hypertensive patients measured by pulsed tissue Doppler imaging

Examination of left ventricular (LV) diastolic dysfunction in hypertensive patients has been based on parameters obtained from the transmitral flow velocity during pulsed Doppler echocardiography. However, these parameters are affected by loading conditions. We evaluated LV diastolic function along the longitudinal and transverse axes by pulsed tissue Doppler imaging (TDI) in 50 hypertensive (HT) patients and 36 age-matched healthy volunteers (N). Transmitral flow velocity was recorded by pulsed Doppler echocardiography. LV posterior wall motion velocity along the longitudinal and transverse axes also was recorded by pulsed TDI. In both groups, peak early diastolic velocity of the LV posterior wall (Ew) along the transverse axis (N: 15.8+/-5.2 cm/s, HT: 12.2+/-4.4 cm/s) was higher than that along the longitudinal axis (N: 12.7+/-3.1 cm/s, HT: 9.5+/-3.3 cm/s). Peak atrial systolic velocity of the LV posterior wall (Aw) along the longitudinal axis (N: 9.1+/-1.8 cm/s, HT: 9.7 +/-2.6 cm/s) significantly exceeded that along the transverse axis (N: 8.0+/-2.2 cm/s, HT: 8.4+/-2.4 cm/s) in both groups. The Ews were lower and the Aws were higher along both axes in the patient group than in the control group. The time intervals from the aortic component of the second heart sound to the peak of the early diastolic wave (IIA-Ews) along both the transverse (N: 142+/-18 ms, HT: 154+/-19 ms) and longitudinal (N: 151 16 ms, HT: 162+/-20 ms) axes were longer in the patient group. In 29 patients, Ews along both axes correlated negatively (transverse: r = -0.80, P < .0001; longitudinal: r = -0.71, P < .0001) and IIA-Ews correlated positively (transverse: r = 0.81, P < .0001; longitudinal: r = 0.74, P < .001) with the time constant of the LV pressure decay during isovolumic diastole. The Aws along both axes in the 24 patients without pseudonormalization in transmitral flow velocity correlated positively (transverse: r = 0.60, P < .001; longitudinal: r = 0.74, P < .0001) with the LV end-diastolic pressure. In conclusion, LV relaxation and filling along the longitudinal and transverse axes were impaired in many patients with hypertension. Pulsed TDI was useful for evaluating LV diastolic dynamics in this disease.