肝细胞癌上皮细胞白蛋白和CK7的表达

目的 探讨人类肝癌肝组织是否存在小上皮细胞（small epithelial cell,SEC),这类细胞是否表达白蛋白CK7抗体,对30例人肝细胞肝癌的手术标本材料作免疫组化染色,对其中10例作超微结构观察和白蛋白及CK7的免疫电镜标记。结果 30例中有20例在肝癌肿瘤边缘和增生的小胆管发现有少量SEC。这类细胞既表达白蛋白,又表达CK7。电镜下,这类SEC体积较小,核大,胞质少胞质内主要为游离核糖体,并有胞质内张力微丝及细胞间连接结构。免疫电镜下,10例中有5例可显示在同一SEC同时表达白蛋白和CK7。结论 人肝细胞癌肝中确实存在SEC。这类SEC具有与人肝母细胞瘤和胆道闭锁肝组织中的SEC一样的形态和免疫表型特点。     

7-硝基吲唑对大鼠脑缺血再灌流保护作用的研究

目的：探讨神经元型一氧化氮合酶抑制剂（ｎＮＯＳＩ）７－硝基吲唑（７－ｎｉｔｒｏｉｎｄａｚｏｌｅ,７－ＮＩ）对脑缺血再灌流保护作用的机理。方法：选用体重１８０－２２０ｇ的雌性Ｗｉｓｔａｒ大鼠,随机分组,左颈外动脉管腔内置渔线经颈内动脉送至大脑中动脉内,使之闭塞。     

Partial Sequence Analysis of the Genome of Human Herpesvirus 7 YY5 Isolated from Saliva Samples

Ｈｕｍａｎｈｅｒｐｅｓｖｉｒｕｓ 7(ＨＨＶ 7)ｉｓｏｎｅｏｆｔｈｅｍｏｓｔｒｅｃｅｎｔｌｙｄｉｓｃｏｖｅｒｅｄｍｅｍｂｅｒｏｆｔｈｅｈｅｒ ｐｅｓｖｉｒｕｓｆａｍｉｌｙ .Ｉｔｗａｓｆｉｒｓｔｉｓｏｌａｔｅｄｆｒｏｍａｃｔｉｖａｔ ｅｄＣＤ4 Ｔｃｅｌｌｓｆｒｏｍｐｅｒｉｐｈｅｒａｌｂｌｏｏｄｍｏｎｏｎｕ ｃｌｅａｒｃｅｌｌｓ (ＰＢＭＣｓ)ｏｆａｈｅａｌｔｈｙｉｎｄｉｖｉｄｕａｌ[1] ,ａｐａｔｉｅｎｔｗｉｔｈｃｈｒｏｎｉｃｆａｔｉｇｕｅｓｙｎｄｒｏｍｅ(ＣＦＳ) [2 ] ,ａｎｄｆｒｏｍｓａｌｉｖａｏｆｈｅａｌ…     

Decreased frequency of a novel T-lymphocyte subset,CD3+CD4−CD7+CD57− T cells,in hepatitis B virus-related end-stage liver disease might contribute to disease progression

CD7 and CD57 are related to the differentiation and functional stages of CD8⁺ T cells. However, the role of their combined presence in CD8⁺ T cells in patients with chronic hepatitis B virus (HBV) infection, especially those with end-stage liver disease, remains unclear. Blood samples from healthy volunteers and patients with chronic hepatitis B were analyzed via Luminex assay and ELISA to measure plasma cytokine levels. Further, recombinant IL-22 was used to stimulate peripheral blood mononuclear cells from healthy volunteers, and the frequency of CD3⁺CD4⁻CD7⁺CD57⁻ T cells and apoptosis rates were investigated via flow cytometry. Patients with end-stage liver disease, particularly those with acute to chronic liver failure, showed decreased CD3⁺CD4⁻CD7⁺CD57⁻ T cell frequency. Furthermore, the prevalence of CD3⁺CD4⁻CD7⁺CD57⁻ T cells was negatively correlated with disease severity, prognosis, and complications (ascites). We also observed that IL-22 promoted apoptosis and brought about a decrease in the number of CD3⁺CD4⁻CD7⁺CD57⁻ T cells in a dose-dependent manner. CD3⁺CD4⁻CD7⁺CD57⁻ T cells displayed a B and T lymphocyte attenuator (BTLA)^highCD25^highCD127^high immunosuppressive phenotype and showed low interferon-γ, tumor necrosis factor-α, granzyme A, and perforin expression levels. The present findings will elucidate the pathogenesis of HBV-related end-stage liver disease and aid the identification of novel drug targets.     

Cdc7 kinase is required for postnatal brain development

The evolutionally conserved Cdc7 kinase plays crucial roles in initiation of DNA replication as well as in other chromosomal events. To examine the roles of Cdc7 in brain development, we have generated mice carrying Cdc7 knockout in neural stem cells by using Nestin-Cre. The Cdc7^Fl/Fl Nestin^Cre mice were born, but exhibited severe growth retardation and impaired postnatal brain development. These mice exhibited motor dysfunction within 9 days after birth and did not survive for more than 19 days. The cerebral cortical layer formation was impaired, although the cortical cell numbers were not altered in the mutant. In the cerebellum undergoing hypoplasia, granule cells (CGC) decreased in number in Cdc7^{Fl/F l}Nestin^Cre mice compared to the control at E15-18, suggesting that Cdc7 is required for DNA replication and cell proliferation of CGC at mid embryonic stage (before embryonic day 15). On the other hand, the Purkinje cell numbers were not altered but its layer formation was impaired in the mutant. These results indicate differential roles of Cdc7 in DNA replication/cell proliferation in brain. Furthermore, the defects of layer formation suggest a possibility that Cdc7 may play an additional role in cell migration during neural development.     

Mechanism of action of a tyrphostin, 3,4-dihydroxy-α-cyanothiocinnamamide, in breast cancer cell growth inhibition involves the suppression of cyclin B1 and the functional activity of cyclin B1/p34cdc2 complex

Tyrphostins are a group of compounds specifically targeted for the inhibition of tyrosine phosphorylation in signal transduction pathways. We studied the effects of a tyrphostin, 3,4-dihydroxy--cyanothiocinnamamide (tyrphostin-47), on hormone-responsive MCF-7 and hormone-unresponsive MCF-7-5C cell growth by DNA analysis for a period of 10 days. The growth of both cell lines was inhibited by this drug at 50 and 100 µM concentrations. Flow cytometric analysis showed that tyrphostin treatment caused a significant delay in the progression of MCF-7 cells through Gl and S phases of the cell cycle. The level of cyclin B1, a component of the mitosis promoting factor (MPF), was reduced by 90% in the presence of 100 µM tyrphostin. The other component of MPF, p34cdc2 kinase, was not affected; however, its functional activity was dramatically reduced, as determined by histone H1 phosphorylation assay. In contrast, G1 cyclins (D1 and E) and tyrosine kinase activity were not markedly affected by tyrphostin-47, as determined by Western immunoblot detection with specific antibodies. Our results suggest that a possible mechanism of tyrphostin action in breast cancer cells might involve the suppression of cyclin B1 and inhibition of the functional activity of cyclin B1/p34cdc2 complex. Our data indicate that the cell cycle machinery might be a target for developing novel drugs for breast cancer.     

Cerebrovascular effects of nitric oxide manipulation in spontaneously hypertensive rats

1. Evidence that nitric oxide (NO) bioactivity is altered in chronic hypertension is conflicting, possibly as a result of heterogeneity in both the nature of the dysfunction and in the disease process itself. The brain is particularly vulnerable to the vascular complications of chronic hypertension, and the aim of this study was to assess whether differences in the cerebrovascular responsiveness to the NO synthase (NOS) inhibitors, N^G-nitro-L-arginine methyl ester (L-NAME) and 7-nitroindazole (7-NI), and to the NO donor 3-morpholinosydnonimine (SIN-1) might indicate one possible source of these complications.
2. Conscious spontaneously hypertensive (SHR) and WKY rats, were treated with L-NAME (30 mg kg⁻¹, i.v.), 7-NI (25 mg kg⁻¹, i.p.), SIN-1 (0.54 or 1.8 mg kg⁻¹ h⁻¹, continuous i.v. infusion) or saline (i.v.), 20 min before the measurement of local cerebral blood flow (LCBF) by the fully quantitative [¹⁴C]-iodoantipyrine autoradiographic technique.
3. With the exception of mean arterial blood pressure (MABP), there were no significant differences in physiological parameters between SHR and WKY rats within any of the treatment groups, or between treatment groups. L-NAME treatment increased MABP by 27% in WKY and 18% in SHR groups, whilst 7-NI had no significant effect in either group. Following the lower dose of SIN-1 infusion, MABP was decreased to a similar extent in both groups (around −20%). There was no significant difference in MABP between groups following the higher dose of SIN-1, but this represented a decrease of −41% in SHR and −21% in WKY rats.
4. With the exception of one brain region (nucleus accumbens), there were no significant differences in basal LCBF between WKY and SHR. L-NAME produced similar decreases in LCBF in both groups, ranging between −10 and −40%. The effect of 7-NI upon LCBF was more pronounced in the SHR (ranging from −34 to −57%) compared with the WKY (ranging from −14 to −43%), and in seven out of the thirteen brain areas examined there were significant differences in LCBF.
5. Following the lower dose of SIN-1, in the WKY 8 out of the 13 brain areas examined showed significant increases in blood flow compared to the saline treated animals. In contrast, only 2 brain areas showed significant increases in flow in the SHR. In the rest of the brain areas examined the effects of SIN-1 upon LCBF were less marked than in the WKY.
6. Infusion of the higher dose of SIN-1 resulted in further significant increases in LCBF in the WKY group (ranging between +30% and +74% compared to saline-treated animals), but no significant effects upon LCBF were found in the SHR. As a result, there were significant differences in LCBF between SIN-1-treated WKY and SHR in six brain areas. In most brain areas examined, cerebral blood flow in SHR following the higher dose of SIN-1 was less than that measured with the lower dose of SIN-1.
7. Despite comparable reductions in MABP (∼20%) in both groups, calculated cerebrovascular resistance (CVR) confirmed that the vasodilator effects of the lower dose of SIN-1 were significantly more pronounced throughout the brain in the WKY (ranging between −3% and −50%; median=−38%) when compared to the SHR (ranging between −10% and −36%; median=−26%). In the animals treated with the higher dose of SIN-1, CVR changes were broadly similar in both groups (median=−45% in WKY and −42% in SHR), but with the reduction in MABP in SHR being twice that found in WKY, this is in keeping with an attenuated blood flow response to SIN-1 in the SHR.
8. The results of this study indicate that NO-dependent vasodilator capacity is reduced in the cerebrovasculature of SHR. In addition, the equal responsiveness to a non-specific NOS inhibitor but an enhanced effectiveness of a specific neuronal NO inhibitor upon LCBF in the SHR could be consistent with an upregulation of the neuronal NO system.

     

Combinations of interferon with platinum complexes: synergistic and antagonistic effects on growth inhibition of MCF-7 and MDA-MB231 breast cancer cells

The growth-inhibitory effects of combining interferons (IFN) with platinum(II) complexes were tested with the aim of comparing these in cultures of estrogen-receptor(ER)-negative MDA-MB₂₃₁ and ER-positive MCF-7 breast cancer cell lines. Another aim was to test whether IFN as a biological response modifier could enhance the effect of the Pt complexes in vitro in an attempt to find an explanation for their more potent antitumor effects in in vivo models. Here it is shown that in both cell lines the combinations of different IFN with all three Pt complexes generally resulted in additive growth inhibition, as calculated by the product of the fraction of surviving cells obtained with each compound alone. Moreover, in MCF-7 cells natural IFN (nIFN) combined with aqua[meso-1,2-bis-(2,6-dichloro-4-hydroxyphenyl)ethylenediamine]sulfatoplatinum(II) (meso-6-Pt) resulted in synergistic inhibition. This synergy could be attributed to the estrogenic property of meso-6-Pt, since the ligand and estradiol also enhanced the inhibitory effect of nIFN. In contrast, the combination of recombinant IFN and meso-6-Pt was antagonistic in MDA-MB₂₃₁ cells. These results show that, in spite of the similar responses of the ER-negative and ER-positive cells to each compound alone, these cells show unexpected differences in their sensitivity to combinations of IFN and the new Pt complex meso-6-Pt.Abbreviations ER estrogen receptor - IFN interferon(s) - nIFN natural interferon - rIFN recombinant interferon - meso-4-Pt aqua[meso-1,2-bis(2,6-difluoro-3-hydroxyphenyl)ethylenediamine]sulfatoplatinum(II) - meso-6-Pt aqua[meso-1,2-bis-(2,6-dichloro-4-hydroxyphenyl) ethylenediamine]sulfatoplatinum(II)     

Aversive properties of theκ opioid agonist U50,488 in the week-old rat pup

Opioids have been shown to produce analgesia and to be reinforcing during the first week of life in the rat. Opioids also have analgesic actions in both the infant and adult, but can be aversive in the mature animal. We examined the aversive effects of the opioid agonist U50,488 during the first postnatal week in the rat pup in three ways. In the first experiment, U50,488, injected peripherally (1.0–30.0 mg/kg), was paired with an odor and pups were tested 8 h later for positional preference for avoidance of that odor. This task is similar to conditioned preference/aversion tests used with adult animals. Both 3- and 7-day-old pups learned to avoid the odor adulterated side at the two higher doses. When exposed to odors previously associated with U50,488, pups at both ages decreased locomotor activity. In a second experiment, acute treatment with U50,488 increased ultrasonic distress vocalizations (USV) equally at 3 and 7 days of age, increased locomotor activity, and decreased rectal temperature. Neither of the latter two effects was correlated with the increase in USV production. The third experiment showed that conditioned odor cues increased USV 8 h later in 3- and 7-day-old pups at 1.0–10.0 mg/kg without changes in activity or rectal temperature. The results from these studies suggest that U50,488 can produce aversions in the neonatal rat pup as it does in the adult.Supported by U.S.P.H.S. grant DA-06600     

Pentoxifylline and intravenous gamma globulin combination therapy for acute Kawasaki disease

We compared the efficacy of oral administration of pentoxifylline (PTX) and intravenous infusions of gamma globulin (IVGG) combination therapy with that of IVGG in reducing the frequency of coronary-artery lesions (CAL) in children with Kawasaki disease (KD), in a randomized trial. All patients with KD received acetylsalicylic acid (30 mg/kg per day), until the 30th day, after the onset of fever, followed by daily acetylsalicylic acid at a dose of 3-5 mg/kg per day there-after, and intravenous IVGG, 200 mg/kg per day, for 5 consecutive days. In addition, patients randomly assigned to PTX and IVGG combination therapy groups received oral PTX at a dosage of 10 mg/kg per day (low-dose) or 20 mg/kg per day (high-dose), in three divided doses until the 30th day. Patients with KD were all free from CAL prior to treatment. We assessed the presence of CAL by two-dimensional echocardiography which was also done prior to treatment and then twice a week after hospital admission. We detected CAL in 3 of 18 patients (16.7%) in the IVGG therapy group, as compared with 2 of 18 patients (11.1%) in the low-dose PTX and IVGG combination therapy group. There were no significant differences between the two groups. In the next study, we detected CAL in 3 of 21 patients (14.3%) in the IVGG therapy group, as compared with none of 22 patients (0%) in the high-dose PTX and IVGG combination therapy group (² = 6.4, P < 0.02). No adverse side-effects were observed in 79 patients with KD.