Accumulation of thiophenes by cell cultures of tagetes patula and the release of 5-(4-Hydroxy-1-butynyl)-2,2'-bithiophene into the medium

Calli of TAGETES PATULA, subcultured one or two times, were used to start liquid cultures. Calli of both subcultures contained thiophene-biocides, mainly 5-(but-3-en-1-ynyl)-2,2'-bithiophene (BBT) and 5-(4-acetoxy-1-butynyl)-2,2'-bithiophene (BBTOAc). Secondary calli contained about 3 times higher concentrations of thiophenes than tertiary calli. The liquid batch cultures consisted of coarse cell aggregates (3-8 mm), the volume of which was doubled each 15 days. In contrast to callus cultures grown on solid medium, cell aggregates grown in liquid medium released thiophenes. The release into the medium was at least 2.3 mg.dm (-3) in 90 days by an average amount of 100 g of fresh cell aggregates and occurred mainly as 5-(4-hydroxy-1-butynyl)-2,2'-bithiophene (BBTOH). In callus BBTOH did hardly occur. The amount of thiophenes recovered in the medium corresponded to 0.02% of the cell dry weight. The productivity of the liquid cultures was not related to the productivity of the original calli, neither was the thiophene production related to the growth rate of the biomass in the liquid cultures. The results indicate that not the selection of calli for thiophene content, but rather the selection of calli with the ability to form cell aggregates is of relevance for the production of thiophenes in liquid cultures.     

Serum concentrations of oestradiol-17beta, progesterone, relaxin and chorionic gonadotrophin during blastocyst implantation in natural pregnancy cycle and in embryo transfer cycle in the rhesus monkey

The present study was undertaken to assess the temporal association between the profiles of serum concentrations of oestradiol-17beta, progesterone, chorionic gonadotrophin (CG) and relaxin in pregnancies established naturally, and after embryo transfer, as well as in failed pregnancies in rhesus monkeys. In naturally mated cycles (group 1) a conception rate of 75% was obtained. In group 1, the mean day of CG detection in serum was 11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day post-ovulation. In group 2, embryo transfer to synchronous, non-mated surrogate recipients was performed; seven embryo transfer cycles yielded three pregnancies which were allowed to continue to term and normal infants were delivered. In embryo transfer cycles the mean day of CG detection was 14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day post-ovulation. A delay of about 3 days was observed in the appearance in circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between natural mated and embryo transfer conception cycles. Significant differences (P < 0.05 for progesterone and P < 0.03 for oestradiol) were obtained for the areas under the curves for progesterone and oestradiol between days 12 and 16 in conception cycles compared with failed pregnancies. These data provide the first observation of the normal hormonal signals associated with maternal recognition of transferred embryos during the peri- implantation period, and suggest that the use of such an experimental primate embryo transfer model may help to elucidate components of maternal and embryonic signal-response mechanisms during embryo implantation.      

Tourniquet inflation after intra-articular morphine and bupivacaine administration following knee arthroscopy

We performed a randomized doubled-blind study to evaluate whether there was a benefit in delay in tourniquet deflation with intra-articular administration of morphine and bupivacaine following operative arthroscopic surgery. In 34 patients the tourniquet was deflated immediately and in 38 patients the tourniquet remained inflated for 10 min following injection. The analgesic efficacy was assessed using pain scores and the amount of supplementary analgesia required. The results demonstrate no benefit in delay in tourniquet deflation.     

急性有机磷农药中毒120例的救治

0　引言　近年来 ,我科在救治急性有机磷农药 (organophos-phorus,OP)中毒方面 ,积累了一些经验 ,现报告如下 .1　对象和方法1 .1　对象　本组 1 2 0例符合《急诊急救学》中的诊断标准 [1 ](男 2 9例 ,女 91例 ) ,年龄 1 .5～ 70岁 ,平均 2 8.6岁 .经口中毒 99例 ,经皮肤中毒 2 1例 .轻度中毒 1 5例 ,中度中毒 42例 ,重度 (含极重度 )中毒 6 3例 . 1 996年 39例 ,1 997年 43例 ,1 998年 38例 . DDV 79例 ,乐果 2 0例 ,混合性中毒 1 0例 ,水胺磷 3例 ,氧化乐果、 391 1、 1 0 5 9、对硫磷各 2例 ,敌百虫 1例 ,药名不详 1 0例 .服毒量 >2 5 …     

Pyruvate kinase in human brain tumours. Its significance in the treatment of gliomas

Summary Pyruvate kinase isozyme distribution was studied in 101 intracranial tumours of various nature and origin, and in normal human brain (both foetal and adult). In foetal brain, five different forms could be detected by electrophoresis (K₄, K₃M, K₂M₂, KM₃, and M₄). In adult brain, the M₄ type, K₃M hybrid, and K₄ are present; the M type is largely predominant. Alanine inhibition of pyruvate kinase can be used to discriminate between M and K-type pyruvate kinase. The results obtained in an alanine inhibition test are in agreement with the electrophoretic pattern. Pyruvate kinase from foetal brain and brain of a newborn is more inhibited compared with pyruvate kinase from adult brain. In adult brain a high residual activity of pyruvate kinase is found in the presence of alanine. Well differentiated neuroepithelial tumours,i.e., astrocytomas, oligodendrogliomas, and ependymomas showed also relatively high residual activities, though less than in normal adult brain. On the contrary, in poorly differentiated gliomas low residual activity was found. Alanine inhibition of pyruvate kinase correlates well with degree of differentiation of these tumours. There is also a strong correlationship between alanine inhibition of pyruvate kinase and one year survival after total or subtotal resection of gliomas in adults.When in gliomas the residual activity is determined not in the centre of the tumour but more towards the periphery, much higher residual activity is found. It is suggested that brain biopsies in which a residual activity higher than 70% is found probably contain no tumour in the paraffin slides.Poorly differentiated gliomas were characterized by the presence of type K, and the hybrids K₃M. In well differentiated gliomas, besides K₄ and K₃M, M₄ was also present. Alanine inhibition was in agreement with the electrophoretic pattern in all tumours. In children (age 1–11 years) gliomas showed no correlation between the distribution of pyruvate kinase isozymes and the histological classification and grading. Of the non-neuro-epithelial tumours studied relatively high residual activities were found for pyruvate kinase in haemangioblastomas, chromophobe adenomas, and craniopharyngiomas. This was also found in an arteriovenous malformation. Other non-neuroepithelial tumours showed much less residual activity. These included benign tumours, meningiomas, neurilemmomas, malignant metastatic tumours, and fibrosarcomas. It was also found in cavernomas. The determination of pyruvate kinase activity in the presence of alanine may be useful for the diagnosis and treatment of intracerebral tumours, in particular gliomas of adults.The alanine inhibition test is a reliable quantitative procedure. It can be performed in 10 minutes, and may well fit in the scope of a surgical procedure.     

Hydrogen peroxide inhibits gap junctional intercellular communication in glutathione sufficient but not glutathione deficient cells

Cell to cell communication via gap junctions is essential in the maintenance of the homeostatic balance of multicellular organisms. Aberrant intercellular gap junctional communication (GJIC) has been implicated in tumor promotion, neuropathy and teratogenesis. Oxidative stress has also been implicated in similar pathologies such as cancer. We report a potential link between oxidative stress and GJIC. Hydrogen peroxide, a known tumor promoter, inhibited GJIC in WB-F344 rat liver epithelial cells with an I50 value of 200 microM. Inhibition of GJIC by H2O2 was reversible as indicated by the complete recovery of GJIC with the removal of H2O2 via a change of fresh media. Free radical scavengers, such as t-butyl alcohol, propylgallate, and Trolox, did not prevent the inhibition of GJIC by H2O2, which indicated that the effects of H2O2 on GJIC was probably not a consequence of aqueous free radical damage. The depletion of intracellular GSH reversed the inhibitory effect of H2O2 on GJIC. The treatment of glutathione- sufficient cells with H2O2 resulted in the hyperphosphorylation of connexin43, which is the basic subunit of the hexameric gap junction protein, as determined by Western blot analysis. TPA, a well-known tumor promoter, also inhibits GJIC via hyperphosphorylation of GJIC, which is a result of protein kinase-C activation. However, H2O2 also induced hyperphosphorylation in GSH-deficient cells that had normal rates of GJIC. Therefore, the mechanism of GJIC inhibition must be different from the TPA-pathway and involves GSH.      

Occurrence of Extended-Spectrum Betalactamases (ESBL) in Dutch Hospitals

Summary The prevalence of ESBL was determined among isolates of Escherichia coli (n = 571) and Klebsiella spp. (n = 196) collected during a 1-week study period in 8 university and 3 large regional laboratories all over the Netherlands. 18 isolates were positive for at least one of the screening tests used, i.e., VITEK-ESBL, E-test ESBL and MIC ratio of ceftazidime/ceftazidime-clavulanic acid, cefotaxime/cefotaxime-clavulanic acid. In 5 of these 18 putative ESBLs no betalactamase production was detectable. A TEM type was found in three E. coli and two Klebsiella spp. An SHV type was present in five Klebsiella spp. In one E. coli and one Klebsiella pneumoniae both enzymes were present. In one Klebsiella oxytoca neither of the two enzymes was present. Using PCR for both ESBL TEM and ESBL SHV, an SHV ESBL was found in one E. coli and four Klebsiella isolates. The mutations at position 238 and 240 were already described. In one E. coli isolate a TEM ESBL was found with three mutations, at position 21, 164 and 265. These mutations were already described in other ESBLs but not in this combination suggesting a new TEM ESBL. The overall prevalence of ESBL producing E. coli and Klebsiella spp. was less than 1% (6 out of 767). Received: December 14, 1998 · Accepted: September 19, 1999     

Angiogenic factors stimulate mast-cell migration

Mast cells accumulate at sites of angiogenesis. The factor(s) that control mast-cell recruitment at these sites have yet to be defined. We sought to determine if angiogenic factors result in mast-cell chemotaxis. In this study, we observed that platelet-derived growth factor-AB (PDGF-AB), vascular endothelial cell growth factor (VEGF), and basic fibroblast growth factor (bFGF) each cause directed migration of murine mast cells at picomolar concentrations, with a typical bell- shaped dose-response curve. Another potent angiogenic factor, platelet- derived endothelial cell growth factor (PD-ECGF), appears to promote chemokinesis of mast cells, whereas tumor necrosis factor-alpha, a weak angiogenic factor, is less robust but still functions as a mast cell chemotactic factor. Epidermal growth factor (EGF), a growth factor with minimal angiogenic properties, was ineffective as a mast cell chemotactic factor. A checkerboard analysis confirmed the directional chemotactic response of PDGF-AB, VEGF, and bFGF, while indicating the chemokinetic response induced by PD-ECGF. Cross-desensitization of growth-factor-induced directed migration was observed between PDGF-AB and bFGF, and also between PDGF-AB and PD-ECGF. Tyrosine kinase- inhibitor genistein effectively dampened the chemotactic responses, whereas pertussis toxin had no effect. In summary, our findings suggest that factors known to act on endothelial cells and stimulate neovascularization may simultaneously serve to recruit mast cells to these sites. The local accumulation of mast cells is believed to facilitate new vessel formation through complex cell:cell interactions.