Consumption of false morel (Gyromitra esculenta Fr.) has been associated not only with acute poisoning, but also with a carcinogenic risk. The hydrolysis of acetaldehyde-N-methyl-N-formylhydrazone (gyromitrin, the main toxic component of false morel) results in the formation of the methylating agents N-methyl-N-formylhydrazine (MFH) and N-methylhydrazine (MMH) (by further hydrolysis of MFH). This study reports traces of N-7-methylguanine (N7MeGu) in liver DNA from mice and a rat treated with gyromitrin. After repeated administration of MMH, N7MeGu was identified in rat liver DNA. In mice exposed to MMH according to a dosing scheme identical to that reported to induce tumours in this species, O6-methylguanine was present in liver and kidney DNA. The results indicate that a relatively low carcinogenic risk is associated with false morel consumption. The risk may be greater in individuals with a decreased detoxification rate (acetylation) of MFH, in whom larger amounts of MMH are formed from gyromitrin. 相似文献
Tested mediator and moderator models of hope, coping, and adjustmentin 39 children with sickle cell disease. In home interviewsparents provided information on demographics and functionaladjustment. Children self-reported levels of hope, coping strategies,and psychological adjustment. Coping strategies moderated, butdid not mediate, the relationship between hope and adjustment.Hope was negatively associated with anxiety when active coping,support coping, and distraction coping was high. Avoidance copingdid not moderate the hope-adjustment relationship but was positivelyrelated to anxiety. No effects were found for depressive symptomsor for the functional measures of adjustment. 相似文献
Prevention Science - The NAMWEZA intervention was implemented, using a ten-session group format, to build skills targeting psychosocial vulnerabilities and enhancing HIV prevention among people... 相似文献
This study examined the effect of high and low anxiety provoking instructions in subjects submitted to a Hyperventilation Provocation Test (HVPT). Subjects were 43 out-patients referred to our clinic for a diagnostic examination of Hyperventilation Syndrome (HVS). Results showed that anxiety levels were affected by the instruction manipulation, but the magnitude of this effect was less than expected and the instruction manipulation had no effect on intensity arid type of reproduced symptoms, nor on symptom recognition. Subjects who met Diagnostic and Statistical manual of Mental Disorders (3rd ed., rev,; American Psychiatric Association, 1987) criteria for Panic Disorder (PD) were not more responsive to the instruction manipulation than non-PD patients. It is argued that the small effect of the manipulation is probably not due to the solidity of the HVPT but to the pervasiveness of pretest cognitions and expectations. In line with this, the report of HVS symptoms appeared highly related to psychological trait measures like anxiety, fear of bodily sensations, and a general tendency to report somatic symptoms. 相似文献
Hyperventilation is considered an important factor in the production of a variety of somatic symptoms. This complex of symptoms is called the Hyperventilation Syndrome (HVS). Recognition of symptoms during the hyperventilation provocation test (HVPT) is a widely used criterion for diagnosing HVS. The validity of this criterion is tested in the present study.
Twenty-three patients suspected of HVS performed a HVPT (hyperventilation during 3 min) and a mental load task (Stroop Color Word Test; CWT). It appeared that about the same number of patients (61%) recognized symptoms during the HVPT as during the CWT (52%), despite severe hypocapnia in the first test and normocapnia in the second. Reporting of symptoms was significantly related to psychological state and trait measures (SCL-90 and STAI scores) and unrelated to the degree of hypocapnia. These data have far reaching consequences, as they not only undermine the validity of the HVPT, but also question the tenability of the concept of HVS. 相似文献
The purpose of this study was to evaluate the association between ATM, TP53 and MDM2 polymorphisms in prostate cancer patients and morbidity after radiotherapy. The presence of ATM (rs1801516), TP53 (rs1042522, rs1800371, rs17878362, rs17883323, and rs35117667), and MDM2 (rs2279744) polymorphisms was assessed by direct sequencing of PCR fragments from 48 patients with histologically proven prostate adenocarcinoma and treated with external beam radiation. The side effects were classified according to the Radiation Therapy Oncology Group (RTOG) score. The results showed no association between clinical characteristics and the development of radiation toxicities (P > 0.05). The C>T transition in the position 16273 (intron 3) of TP53 (rs35117667) was significantly associated with the risk of acute skin toxicity (OR: 0.0072, 95% CI 0.0002–0.227, P = 0.003). The intronic TP53 polymorphism at position 16250 (rs17883323) was associated with chronic urinary toxicity (OR: 0.071, 95%CI 0.006–0.784, P = 0.032). No significant associations were found for the remaining polymorphisms (P > 0.05). The results show that clinical characteristics were not determinant on the developing of radiation sensitivity in prostate cancer patients, and intronic TP53 polymorphisms would be associated with increased acute and chronic radiation toxicities. These observations corroborate the importance of investigating the genetic profile to predict adverse side effects in patients undergoing radiotherapy. 相似文献
We describe two patients with newly diagnosed dermatoses localizing to the radiotherapy field following treatment for breast cancer. Patient 1 was a 53‐year‐old woman who developed bullous morphoea on her left breast two years after radiotherapy. Patient 2 was a 43‐year‐old woman who developed urticaria pigmentosa on her right breast eight months after radiotherapy and similar lesions gradually developed beyond the radiotherapy field. Both patients experienced a significant delay in diagnosis due to diagnostic confusion and concern over breast cancer recurrence. Irradiated skin demonstrates gradual and sustained alterations in fibrosis due to the production of long‐lived cytokines and chemokines. These changes can induce a koebnerizing response in conditions such as morphoea and urticaria pigmentosa. We explore the mechanisms behind radiotherapy‐induced skin changes, and highlight the potential for radiotherapy to exacerbate or unmask underlying dermatoses and systemic disease in the months and years following treatment. 相似文献
Introduction:Human Immunodeficiency Virus (HIV) infection remains prevalent co-morbidity, and among fracture patients. Few studies have investigated the role of exercise interventions in preventing bone demineralization in people who have fractures and HIV. If exercise exposed, HIV-infected individuals may experience improved bone health outcomes (BMD), function, quality of life (QoL). The study will aim to assess the impact of home based exercises on bone mineral density, functional capacity, QoL, and some serological markers of health in HIV infection among Nigerians and South Africans.Methods and design:The study is an assessor-blinded randomized controlled trial. Patients managed with internal and external fixation for femoral shaft fracture at the study sites will be recruited to participate in the study. The participants will be recruited 2 weeks post-discharge at the follow-up clinic with the orthopaedic surgeon. The study population will consist of all persons with femoral fracture and HIV-positive and negative (HIV-positive medically confirmed) aged 18 to 60 years attending the above-named health facilities. For the HIV-positive participants, a documented positive HIV result, as well as a history of being followed-up at the HIV treatment and care center. A developed home based exercise programme will be implemented in the experimental group while the control group continues with the usual rehabilitation programme. The primary outcome measures will be function, gait, bone mineral density, physical activity, and QoL.Discussion:The proposed trial will compare the effect of a home-based physical exercise-training programme in the management of femoral fracture to the usual physiotherapy management programmes with specific outcomes of bone mineral density, function, and inflammatory markers.Trial registration:The study was prospectively registered with the Pan African Clinical Trials Registry (Reference number – PACTR201910562118957) on October 21, 2019. (https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=9425). 相似文献
Initiation of translation of the RNA genomes of picornaviruses such as poliovirus and encephalomyocarditis virus is cap-independent and results from interaction of ribosomes with a segment of the 5' noncoding region of these mRNAs termed the internal ribosomal entry site. Genetic and biochemical studies have previously shown that a 57-kDa cytoplasmic RNA-binding protein (p57) plays an essential role in this translation mechanism. We have now found that p57 shares physical, biochemical, and antigenic properties with the pyrimidine tract-binding protein (PTB), a nuclear protein that has been implicated in various processes involving pre-mRNA. These data indicate that p57 and PTB are the same protein. Purified recombinant PTB bound specifically to a bulged hairpin within the internal ribosomal entry site of encephalomyocarditis virus and had a much lower affinity for a mutated derivative of this hairpin and for unrelated RNAs. Immunodepletion of p57/PTB from a HeLa cell-free lysate inhibited translation of poliovirus and encephalomyocarditis virus mRNAs but had no effect on translation of beta-globin mRNA, confirming the essential role of p57 in translation by internal ribosomal entry. 相似文献