Proceedings. The monitoring of chemical contaminants in food.

Two different smoking systems were tested by exposing Syrian golden hamsters to the smoke of cigarettes labelled with [¹⁴C]dotriacontane-16,17 (DOT). In 3 experiments, the activity of mainstream and sidestream Total Particulate Matter (TPM) and of butts and ash was determined. Comparing the results, the system involving individual exposure was shown to provide the animals with higher amounts of mainstream TPM than the system using simultaneous exposure of numerous animals.     

High salt diet may promote progression of breast tumor through eliciting immune response

ObjectiveDietary patterns are believed to regulate tumor progression by altering the tumor microenvironment. Of note, a high salt diet is a risk factor for various diseases. However, the role of high salt intake in the progression of cancers remains unknown.MethodsWe constructed an in vivo high salt diet model in MMTV-PyVT mice with spontaneous tumor-forming properties to explore the role of a high salt diet in the progression of breast cancer as well as the modulation of the tumor microenvironment. Also, in vitro experiments were performed to understand the mechanism.ResultsHigh salt diet accelerated the development (P < 0.05) and lung metastasis (P < 0.05) of breast cancer in MMTV-PyVT mice, compared to the normal diet model. Moreover, higher frequency of Th17 cells in circulation, tumor tissue and draining lymph node tissue were observed in the high salt diet model (P < 0.05 for all). In vitro, co-culture with Th17 cells facilitated the proliferation, migration and invasion of MCF-7 human breast cancer cells, while these enhanced aggressive behaviors could be reversed by application of 1,25-vitamin D₃ which could inhibit the differentiation of Th17 cells (P < 0.001 for all). In vitro, co-culture with Th17 cells activated MAPK signaling in MCF-7 cells (P < 0.001 for all). Consistently, activated MAPK/ERK signaling was observed by immunohistochemistry in breast cancer cell nodes in the high salt diet model (P < 0.05 for all). Mechanistically, higher level of IL-17F could be detected in breast tumors and serum from the high salt diet model through qRT-PCR and ELISA (P < 0.05 for all). IL-17F treatment facilitated the proliferation, migration and invasion of MCF-7 human breast cancer cells and activated MAPK/ERK signaling in MCF-7 cells (P < 0.001 for all). Moreover, the tumor-promoting function induced by Th17 cells and IL-17F could be inhibited by the administration of ERK inhibitor (sch772894) (P < 0.001 for all). Lastly, high concentration NaCl-induced Th17 cells promoted the proliferation, migration and invasion of MCF-7 human breast cancer cells and activated MAPK/ERK signaling in MCF-7 cells which could be inhibited by neutralizing anti-IL-17F (P < 0.001 for all).ConclusionHigh salt intake accelerates the growth of breast cancer and facilitates lung metastasis, as well as increases the level of Th17 cells. Increased Th17 cells might promote the growth of breast cancer via the secretion of IL-17F to activate the MAPK signaling pathway in breast cancer cells.     

Proceedings. Microbiological hazards.

The in vivo effect of a single oral dose (30 mg/kg body weight) of dieldrin on proteolipid and phosphatidopeptide content of liver and brain and on total protein of liver, brain, plasma, muscle and kidney of rat was studied. Incorporation of [¹⁴C]leucine into total protein of liver was increased whereas labelling of total protein of muscle was decreased. Labelling of total protein of other tissues was unchanged. Incorporation into liver phosphatidopeptides was increased and this was consistent with an involvement of these compounds in increasing protein synthesis in the dieldrin-treated group. Proteolipid protein content of brain was increased and that of liver unchanged. There was, however, no change in the labelling of brain or liver proteolipids.     

Proceedings. Natural hazards occurring in foods.

Eleven Nubian goats were fed with Jatropha curcas seeds at doses ranging from 0.25 g to 10 g/kg/day. All dose levels were found to be toxic with fatal consequences within 2 to 21 days. Liver biopsy samples taken 2 days after the start of feeding and subsequent biopsies showed congestion, varying degrees of fatty change, considerable reduction in glycogen content and necrosis of the hepatocytes. Lack of appetite, reduced water consumption, diarrhoea, dehydration, sunken eyes and a steadily deteriorating condition were important clinical signs of Jatropha intoxication intgoats. In all animals there was a decrease in the level of glucose and a marked rise in the concentration of arginase and glutamate oxaloacetate transaminase (GOT) in the serum. Post-mortem examination revealed haemorrhage in the rumen, reticulum, kidney, spleen and heart, catarrhal or haemorrhagic abomasitis and enteritis, congestion and oedema of the lung and excessive fluid in serous cavities.     

17O n.m.r. studies of amino acids in the solid state,in single- and polycrystalline forms

A single crystal of ¹⁷O enriched α-glycine was grown by slow evaporation of aqueous solution. ¹⁷O n.m.r. studies of the α-glycine molecule in single crystalline form revealed five ¹⁷O transitions each consisting of two lines due to inequivalency of the oxygen atoms in the unit cell, with each of these lines revealing a dipolar interaction between the ¹⁷O and the nearest hydrogen atom. The spectral width was found to be of the order of magnitude of MHz and the linewidths of the order of magnitude of 2 kHz.     

Further investigation of the stimulus properties of chlordiazepoxide and zolpidem. Agonism and antagonism by two novel benzodiazepines

The effects of Ro 16-6028 and Ro 17-1812, two novel benzodiazepines with mixed agonist and antagonist properties, were studied in rats trained to discriminate either chlordiazepoxide or the benzodiazepine receptor ligand zolpidem. In rats discriminating 5 mg/kg chlordiazepoxide from saline both Ro 16-6028 and Ro 17-1812 produced responding on the drug lever. At a dose of 10 mg/kg both compounds gave rise to 100% responding on the lever associated with chlordiazepoxide. The dose-response curve produced by Ro 16-6028 was flatter than that for Ro 17-1812, however. The discriminative cue produced by 2 mg/kg zolpidem did not generalise to either Ro 16-6028 or Ro 17-1812. In contrast, both of those compounds antagonised the zolpidem cue and also antagonised the reduction in response rates produced by zolpidem. These results are consistent with previous findings that Ro 16-6028 and Ro 17-1812 may exert anxiolytic-like effects typical of benzodiazepines while antagonising the depressant actions of benzodiazepine receptor ligands. The results are also consistent with the suggestion that the discriminative cues produced by chlordiazepoxide and zolpidem may be mediated, at least partially, by activity at different sub-types of benzodiazepine receptors.     

雌酮和16,17-吡唑雌酮对大鼠子宫雌激素受体的作用

16,17-吡唑雌酮(16,17-PES)是一个以雌酮为母体而合成的雌酮衍生物。前曾报道,它的雌激素样活性仅为雌酮的1/3或1/15,但却具有与雌酮相同的降血脂作用。本研究用大鼠重复了雌激素活性的测定,获得与过去相似的结果。同时证明,它们的雌激素活性与子宫雌激素受体浓度之间存在着平行关系,即经雌酮和16,17-PES处理的动物,无论按每个子宫所含受体数目或每mg蛋白所含受体浓度,前者均显著高于后者。但体外试验表明,二者取代~3H-雌二醇与雌激素受体结合的竞争曲线几乎完全重叠,说明二者对受体的亲和力是相等的。大鼠注射同一剂量的雌酮和16,17-PES后,它们在子宫内的分布量分别为69.0和38.4μg/g,这一结果可用来解释二者雌激素活性的差异,也可解释子宫受体数目的差异。油水分布系数的测定未能说明雌酮和16,17-PES在子宫分布量的不同。     

雌酮和16,17-吡唑雌酮对大鼠子宫雌激素受体的作用

16,17-吡唑雌酮(16,17-PES)是一个以雌酮为母体而合成的雌酮衍生物。前曾报道,它的雌激素样活性仅为雌酮的1/3或1/15,但却具有与雌酮相同的降血脂作用。本研究用大鼠重复了雌激素活性的测定,获得与过去相似的结果。同时证明,它们的雌激素活性与子宫雌激素受体浓度之间存在着平行关系,即经雌酮和16,17-PES处理的动物,无论按每个子宫所含受体数目或每mg蛋白所含受体浓度,前者均显著高于后者。但体外试验表明,二者取代³H-雌二醇与雌激素受体结合的竞争曲线几乎完全重叠,说明二者对受体的亲和力是相等的。大鼠注射同一剂量的雌酮和16,17-PES后,它们在子宫内的分布量分别为69.0和38.4μg/g,这一结果可用来解释二者雌激素活性的差异,也可解释子宫受体数目的差异。油水分布系数的测定未能说明雌酮和16,17-PES在子宫分布量的不同。     

Ki-67、P16、CK17在鉴别宫颈非典型鳞化、未成熟鳞化中的意义

目的：研究Ki-67、P16、CK17在宫颈非典型鳞化(AIM)、未成熟鳞化(IM)中的表达,以探讨Ki-67、P16、CK17对于AIM与IM的鉴别诊断意义。方法应用免疫组化技术检测诊断为AIM及IM的100例患者中Ki-67、P16及CK17的表达情况,并进行统计学分析。结果100例患者中57例AIM,43例IM,与原诊断比较误诊率达12%。57例AIM Ki-67阳性率75.4%,P16阳性率77.2%,CK17阳性率35.1%;43例IM中Ki-67阳性率4.7%,P16阳性率16.3%,CK17阳性率97.7%,差异均有统计学意义(P<0.01)。 Ki-67、P16、CK17联合检测方法均优于Ki-67、P16联合检测和P16、CK17联合检测,差异均有统计学意义(P<0.05)。结论 Ki-67、P16、CK17联合检测对于AIM与IM的鉴别诊断有重要意义。     

Dimethylamine and diet.

Forty-six different foods eaten by six healthy male volunteers were investigated as potential sources of the aliphatic secondary amine, dimethylamine. None that were representatives from the fruit and vegetable, meat, dairy and grain produce categories afforded any measurable elevation in urinary dimethylamine output following ingestion. All of the statistically significant increases occurred after consumption of fish and seafoods. However, within this category a wide variation was observed. The highest values were obtained for coley, squid and whiting with cod, haddock, sardine, skate and swordfish also producing substantial increases. Freshwater trout, plaice and prawns gave no discernable effect. It seems that not all fish and seafoods may be treated equally with regards to human dimethylamine exposure and that the situation is more complicated than at first appears.     

CK10、CK14、CK17、P16在宫颈不成熟鳞状化生及宫颈上皮内瘤变中的表达

目的探讨CK10、CK14、CK17、P16在宫颈不成熟鳞状化生（IM）及宫颈上皮内瘤变（CIN）中的表达和意义。方法应用SP免疫组化法检测CK10、CK14、CK17、P16在宫颈45例IM及120例CIN标本中的表达情况,并对结果进行分析。结果 CK17、CK10在宫颈IM中的阳性表达率分别为100%、95.6%,明显高于LSIL和HSIL组（分别为CK17：11.3%、15%;CK10：20.0%、22.5%。P均〈0.01）;P16在LSIL和HSIL中的表达率均为100%,明显高于IM组（13.3%,P〈0.01）;CK14在IM组、LSIL和HSIL组的表达率分别为64.4%、61.2%、67.5%,三组间差别不显著（P〉0.05）;在LSIL和HSIL组,CK14、P16的表达率无明显差别,但在LSIL中,阳性细胞位于上皮下1/3层,在HSIL中,位于上皮上1/3或全层。结论①CK17、CK10、P16在宫颈IM和CIN病变中表达具有明显差异,有助于两种病变的鉴别诊断;②CK14、P16可用于LSIL和HSIL的辅助鉴别诊断。