天然胶乳橡胶避孕套的体外细胞毒性试验研究

目的研究天橡避的体外细胞毒性,调查国内市售避孕套的细胞毒性现状。方法遵照GB/T16886.5和GB/T14233.2-2005(第2部分:生物学试验方法)体外细胞毒性的实验原则,采用琼脂覆盖法、显微镜观察法、噻唑蓝(MTT)比色法,在小鼠成纤维细胞(L929株)上对受试避。结果用琼脂覆盖法检测,6批不同品牌避孕套均具有2级细胞毒性反应。用显微镜观察法检测,6批不同品牌避孕套(按6 cm2/ml比例浸提)在浸提液浓度为100%、50%、20%和10%时,分别具有4级、4级、2级、1或0级细胞毒性反应。用MTT比色法检测,来自6个品牌的15批避孕套(按6 cm2/ml比例浸提),在浸提液浓度为50%、20%、10%时,分别具有4级(RGR≤15%)、2级(RGR:50%～70%)、1级(RGR≥80%)细胞毒性反应。结论试验表明受试天然胶乳橡胶避孕套均有不同程度的细胞毒性反应。MTT比色法具有定量评价的优点,易于操作,与琼脂覆盖法和显微镜观察法相比更适合避的细试验。     

Inhibition of murine granulopoiesis in vitro by dexamethasone

The effect of dexamethasone on mouse bone marrow granulocyte-monocyte precursor cells (CFU-C) was studied in vitro. Dexamethasone inhibited colony formation in the presence of maximally stimulating concentrations of colony-stimulating activity. A mean colony reduction of 55% occurred at 10⁹ M dexamethasone and inhibition was observed at concentrations as low as 10^?12 M. The dexamethasone suppression could be abrogated by progesterone. These studies provide evidence that the committed granulocyte-monocyte stem cell has a glucocorticoid receptor mechanism that when activated results in inhibition of cellular proliferation in vitro.     

In vitro antiproliferative efficacy of Interferon-alpha,-gamma and Tumor Necrosis Factor on two human renal tumor xenografts

Summary The in vitro antitumor activity of recombinant alpha-and gamma-Interferon as well as recombinant Tumor Necrosis Factor alpha was tested on renal cell carcinoma xenografts using the double layer soft agar method. Using this assay, the effect of the drugs on the clonogenic potential of tumor cells in soft agar was determined and used as an indication for the antiproliferative capacity of these drugs. There appeared to be a differential response of the tested xenografts towards these drugs in a dose dependent way. However, when used in combination in most cases an additive or synergistic effect was observed. Even though again the response was differential, the combination of alpha-Interferon (10 ng/dish) and Tumor Necrosis Factor (100 ng/dish) resulted in a complete inhibition of colony formation in soft agar for both tumor lines. We conclude that there is a direct effect of alpha-Interferon, gamma-Interferon and Tumor Necrosis Factor on renal cell carcinoma xenografts. In combination drug tests the effect of alpha-Interferon and Tumor Necrosis Factor was strongly synergistic. The implication of these studies for in vivo use of these drugs remain to be established.     

STUDIES ON THE EFFECT OF ORALLY ADMINISTERED AGAR ON THE SERUM BILIRUBIN LEVEL OF PREMATURE INFANTS and MATURE NEWBORNS

ABSTRACT: Windorfer, A. Jr, Kunzer, W., Bolze, H., Ascher, K., Wilcken, F. and Hoehne, K. (University Children's Hospital, Freiburg i. Brg., West Germany). Studies on the effect of orally administered agar on the serum bilirubin level of premature infants and mature newborns. Acta Paediatr Scand, 64:699, 1975.–The effect of orally administered agar on the serum concentration of bilirubin was tested in 366 premature and newborn infants. For this purpose two different concentrations of agar were added to the milk for 8–10 days. On none of the groups tested did the serum level of bilirubin show a significant decrease after administration of agar. Therefore the attempt to lower the level of serum bilirubin in premature and newborn infants by inhibiting enteric reabsorption by means of adsorbents must be considered a failure.     

Use of the membrane filtration technique and Staib agar for the detection of Cryptococcus neoformans in the urine of AIDS patients--a contribution to diagnosis, therapy and pathogenesis of cryptococcosis

For the cultural control of Cryptococcus neoformans (Cr.n.), among the routinely examined standard specimens like CSF, sputum, blood, etc., urine earns special attention. The combination of membrane filtration technique (MFT) and Staib agar for the detection of Cr.n. from body fluids as described by Staib in 1963 was used for the cultural isolation of Cr.n. from urine of AIDS patients. In 3 examplary cases the diagnostic significance of this method could be demonstrated: The brown colour effect (BCE) of Cr.n. of a single CFU, as well as in colonies growing with a high density, was produced on average within 3-5 d/26 degrees C. The method was found to be useful for the evaluation of antimycotic therapy. One example of the survival of a few CFUs of Cr.n. under treatment with fluconazole as compared to the efficacy of therapy with amphotericin B + flucytosine, and one example of a re-emergence of Cr.n. in the urogenital tract after a too short duration of treatment with amphotericin B + flucytosine are shown. For the exclusion of the survival of single CFUs of Cr.n. in the urogenital tract of males, quantities up to 1 l of urine for the combination of MFT and Staib agar are proposed. As a secondary observation, it was found that this diagnostic combination in addition to its primary purpose, can serve to detect the metabolic end products of the human body present in urine which may influence capsule formation of Cr.n. neoformans.     

Cryptococcus neoformans in the Seminal Fluid of an AIDS Patient. A Contribution to the Clinical Course of Cryptococcosis: Cryptococcus neofomans im Sperma eines AIDS-Patienten. Ein Beitrag zum Minischen Verlauf der Cryptococcose

In a 33-year-old HIV-positive homosexual male suffering from unexplained headache, cryptococcosis was diagnosed in a progressive secondary stage. After treatment with the standard combination therapy of amphotericin B + flucytosine for 34 d, the patient was clinically symptom-free and discharged, upon his own request, from the hospital. He remained under ambulatory mycological control. After an interval of 65 d during which the urine had been free from Cryptococcus neoformans (Cr.n.), the fungus could not be isolated from urine but 3 X 10(5) CFUs/ml were found in the seminal fluid. Andrologically, teratospermia and hyposemia were present. There were no clinical signs in the genitourinary tract including the prostate. The significance of ecological niches for Cr.n. colonization of the genitourinary tract after antimycotic therapy is discussed. In such cases, in addition to cultural examination of urine for Cr.n. by the membrane filtration technique (MFT) and Staib agar, an additional cultural examination of seminal fluid is recommended. It is also proposed to pay more attention to Cr.n. in andrological examinations. Special regard should be given to a possible occurrence of Cr.n. in the seminal fluid of AIDS patients. In cytology of the seminal fluid, use of the Giemsa stain is unsuitable for the purpose of Cr.n. detection. For this reason, it should be supplemented by PAS staining.     

A rapid method for determination of growth supporting and toxic hormone levels in plant cell culture

Summary The use of an agar diffusion method for the optimization of the phytohormone concentrations in growth media for plant cell cultures was studied. The method allows a rapid determination of both growth-supporting levels as well as toxic levels of the phytohormones. These levels were determined for aTabernaemontana divaricata cell line and the results could be extrapolated to suspension cultures.     

Heterogeneity of in vitro growth pattern of megakaryocyte progenitors (CFU-M) in myeloproliferative disorders

In groups of 26 patients with myeloproliferative disorders (MPD), 8 with chronic myelogenous leukaemia (CML); 8 with polycythaemia vera (PV); 10 with essential thrombocythaemia (ET); and 6 patients with reactive thrombocytosis (RT), we studied the growth characteristics of bone marrow CFU-M in agar culture. The bone marrows from all the patients with MPD formed so called endogenous CFU-M colonies, in the absence of PHA-LCM, that increased in a dose-dependent manner with the addition of increasing concentrations of normal human AB-citrated plasma (NH-ABCP), while the bone marrows from all the patients with RT and from healthy controls formed few or no endogenous CFU-M colonies. In MPD, the endogenous CFU-M growth was enhanced by normal T cells in a dose-dependent fashion, and was decreased with the depletion of T cells from the marrow cells. These results suggest that the formation of endogenous CFU-M colonies is caused by hypersensitivity of CFU-M in MPD to NH-ABCP, which may contain a small amount of Meg-CSF, and/or by in vitro T cell stimulation. Among MPD, the endogenous CFU-M growth in ET was significantly lower than that of other MPD patients; however, the total number of ET CFU-M grown in the presence of PHA-LCM was the highest. These data show that the bone marrow CFU-M in MPD are heterogeneous with respect to in vitro growth pattern or sensitivity to exogenous Meg-CSF.