Minisatellite rearrangements are increased in liver tumours induced by transplacental aflatoxin B1 treatment of hepatitis B virus transgenic mice, but not in spontaneously arising tumours

Transgenic mice carrying an integrated subgenomic human hepatitis B virus (HBV) DNA fragment coding for the viral envelope polypeptides, represent a model for the study of the mechanisms involved in hepatocarcinogenesis. The mice develop a progressive liver injury characterized by inflammation, regenerative hyperplasia and dysplasia terminating in hepatocellular carcinoma (HCC) at around 18-21 months of age. No alterations in specific oncogenes and tumour suppressor genes in the HCC arising in this transgenic model have been observed. However, onset of liver tumours is significantly earlier in mice treated with aflatoxin B1 (AFB1). In order to examine more generally for genetic rearrangements during the natural history of the disease, DNA multilocus fingerprinting was performed using probes recognizing mouse minisatellites. Liver tumour samples from HBV transgenic mice either untreated or treated with AFB1 transplacentally were included in the study. In a total of 28 tumour samples from HBV transgenic mice receiving no carcinogen treatment, using three minisatellite probes, no alterations were detected. The frequency of rearrangements using any one of the three probes is calculated to be below 0.2%. This result demonstrates that genetic instability in minisatellite sequences is not a common event associated with HBV gene expression and liver injury in this model. In 11 liver tumours from mice exposed to AFB1 transplacentally six had minisatellite alterations (band gains and losses) revealed by at least one of the three probes used. The frequency of rearrangements was between 1.1% and 2% depending on the minisatellite probe. These data show that genetic alterations can be induced by transplacental exposure to AFB1 and suggest that genetic instability could be important in hepatocarcinogenesis with combined exposures to AFB1 and HBV.      

Effects of long-term growth hormone releasing hormone 1 -29 in significantly short children

Seven children with significant idiopathic short stature (SISS) whose heights were significantly below the third percentile (SD score for height —2.5 to —3.5) and who had normal levels of growth hormone (GH) were treated with growth hormone releasing hormone (GH-RH) in a dose of 30 /μg/kg/day. Therapy was discontinued if patients failed to increase their rates of growth by more than 2.0 cm/year over their pre-therapy growth rate. Treatment was discontinued in two of the patients after 12 months but was continued in the other five for 24 months. These data demonstrate that some patients with SISS grow well during the first 2 years of treatment with GH-RH.     

肾上腺髓质素的分子生物学意义及对肾脏损伤的影响

0 引言 肾上腺髓质素(adrenomedullin,ADM)是一种从人嗜铬细胞瘤组织中分离纯化出的多肽,它在正常肾上腺髓质及源于肾上腺髓质的嗜铬细胞瘤中含量丰富.近年来发现ADM在肾脏功能调节方面起着重要作用,现对ADM的生物学特性、生物学作用及其对肾脏的作用进行概述.     

Inappropriate use of carbamazepine and vigabatrin in typical absence seizures

Carbamazepine and vigabatrin are contraindicated in typical absence seizures. Of 18 consecutive referrals of children with resistant typical absences only, eight were erroneously treated with carbamazepine either as monotherapy or as an add-on. Vigabatrin was also used in the treatment of two children. Frequency of absences increased in four children treated with carbamazepine and two of these developed myoclonic jerks, which resolved on withdrawal of carbamazepine. Absences were aggravated in both cases where vigabatrin was added on to concurrent treatment. Optimal control of the absences was achieved with sodium valproate, lamotrigine, or ethosuximide alone or in combination.     

Relationship between Myopia and Optical Components - A Study among Chinese Hong Kong Student Population

Purpose: To establish the prevalence and severity of myopia among the Chinese Hong Kong students and to study the relationship between myopia and optical components.Methods;One thousand and seventy-five freshmen of the 1993-1994 academic year in the Chinese University of Hong Kong underwent the eye examination including evaluation of refractive error, keratometry, and A-scan ultrasonic biometry. The data were analyzed with the SPSS/PC 4. 01 statistical package. Results: The prevalence of myopia was 91. 7% with the mean refraction being -4. 00 ± 2. 64D in this young adult population. The statistical analyses demonstrated a significant correlation between refractive value and axial length of the globe (r=-0. 78), vitreous length (r=-0. 76), anterior chamber depth (r=-0. 33), lens thickness (r = 0. 13) and corneal curvature (r = 0. 19). Conclusion: The refractive status is mainly dependent on the axial length. In general, the higher the myopia was, the longer the eyeball, the deeper the anterior chamber,     

Therapeutic effectiveness and safety of outdated human red blood cells rejuvenated to improve oxygen transport function, frozen for about 1.5 years at 80 C, washed, and stored at 4 C for 24 hours prior to rapid infusion

After storage at 4 C for 20 to 28 days, red blood cells were biochemically modified to improve their oxygen transport function which had deteriorated during liquid storage. The solution used for rejuvenation contained pyruvate, inosine, glucose, phosphate, and adenine (PIGPA Solution B). The rejuvenated red blood cells were frozen with 40% W/V glycerol in a polyolefin plastic bag and were stored in the frozen state for about 1.5 years at −80 C. After thawing and washing the red blood cells were stored at 4 C in a sodium chloride- glucose-phosphate solution for 24 hours before transfusion. A pool of four to ten units was rapidly transfused to each of 14 elderly anemic recipients, 11 of whom had cardiopulmonary insufficiency. Recovery of the red blood cells after the freeze-thaw process was about 97 per cent, and after the freeze-thaw-wash process about 90 per cent. The 24− hour posttransfusion survival values were about 75 per cent, and the long-term survival values were about 85 days depending on the disease state of the recipient. The red blood cells had 1.5 times normal 2.3- DPG levels and a decreased affinity for oxygen at the time of transfusion and were able to delivery oxygen at high oxygen tension immediately after the rapid infusion of pools of from four to ten units through a 40-or 170-micron filter. Plasma hemoglobin levels were consistent with extravascular sequestration of nonviable red blood cells, and uric acid levels were not increased during the immediate 24− hour posttransfusion period.     

急性冠脉综合征患者强化他汀治疗与心衰入院危险

目的:确定强化他汀治疗是否可以降低高危患者心衰(HF)的入院危险。背景:强化他汀治疗与缺血性事件的关系已被证实,但其与HF发生危险的关系还不确定。方法:PROVEIT-TIMI2(2ThePravastatinorAtorvastatinEvaluationandInfectionTrial-ThrombolysisInMyocardialInfarction,22帕伐他汀或阿托伐他汀评价与感染试验——心肌梗死溶栓22)研究将4162例患者进行随机分组,分别接强化他汀(阿托伐他汀80mg)或中度他汀(帕伐他汀40mg)治疗。在平均24个月的随访期中,因心住院发生在随机分组后的30多天。并测量基线的型利钠肽(BNP)水平。结果:阿…