Hydrophobic Bombyx mori Silk Fibroin: Routes to Functionalization with Alkyl Chains

Bombyx mori silk fibroin (SF) is a very versatile biopolymer due to its biocompatibility and exceptional mechanical properties which make possible its use as a functional material in several applications. SF can be modified with a large variety of chemical approaches which endow the material with tailored chemical–physical properties. Here, a systematic investigation of different routes is reported to graft long alkyl chains on SF based on both liquid- and solid-phase, aiming to modulate its hydrophobic behavior. The liquid phase method involves direct activation of SF tyrosine residues via diazo coupling and cycloaddition reactions, generating hydrophobic materials insoluble in any common solvent. The solid phase approach consists of the chemical modification of drop-casted SF films by esterification of hydroxyl groups of serine, threonine, and tyrosine SF residues with acyl chlorides of fatty acids. For the solid-state functionalization, a new class of hydrophobic pendant groups is synthesized, based on triple esters of gallic acid anhydrides, that are reacted with the biopolymer to further enhance its resulting hydrophobic features.     

Factor analysis, causal indicators and quality of life

Exploratory factor analysis (EFA) remains one of the standard and most widely used methods for demonstrating construct validity of new instruments. However, the model for EFA makes assumptions which may not be applicable to all quality of life (QOL) instruments, and as a consequence the results from EFA may be misleading. In particular, EFA assumes that the underlying construct of QOL (and any postulated subscales or factors) may be regarded as being reflected by the items in those factors or subscales. QOL instruments, however, frequently contain items such as diseases, symptoms or treatment side effects, which are causal indicators. These items may cause reduction in QOL for those patients experiencing them, but the reverse relationship need not apply: not all patients with a poor QOL need be experiencing the same set of symptoms. Thus a high level of a symptom item may imply that a patient's QOL is likely to be poor, but a poor level of QOL need not imply that the patient probably suffers from that symptom. This is the reverse of the common EFA model, in which it is implicitly assumed that changes in QOL and any subscales cause or are likely to be reflected by corresponding changes in all their constituent items; thus the items in EFA are called effect indicators. Furthermore, disease-related clusters of symptoms, or treatment-induced side-effects, may result in different studies finding different sets of items being highly correlated; for example, a study involving lung cancer patients receiving surgery and chemotherapy might find one set of highly correlated symptoms, whilst prostate cancer patients receiving hormone therapy would have a very different symptom correlation structure. Since EFA is based upon analyzing the correlation matrix and assuming all items to be effect indicators, it will extract factors representing consequences of the disease or treatment. These factors are likely to vary between different patient subgroups, according to the mode of treatment or the disease type and stage. Such factors contain little information about the relationship between the items and any underlying QOL constructs. Factor analysis is largely irrelevant as a method of scale validation for those QOL instruments that contain causal indicators, and should only be used with items which are effect indicators.     

Using patient surveys to measure the quality of outpatient care in Kraków, Poland.

OBJECTIVE: To test the feasibility of using patient reported information to create indicators of quality (access, patient experience--including satisfaction, and clinical quality) with the goal of providing Kraków city clinic managers (and potentially other audiences) with information about the quality of outpatient care in selected clinics. Setting and methods. Almost 2,000 patients from 19 outpatient clinics in Kraków, Poland were surveyed in November and December 1997 and January 1998. We prepared a self-completed questionnaire to capture data about the patient's experience with access to services, interactions with registration staff, communication with the doctor, information received from the doctor, and receipt of preventive services. RESULTS: Access varied across clinics. For example, 84% of patients waited less than 10 minutes at registration, whereas only 53% of patients waited less than 30 minutes to see the doctor. Among those who tried to register by telephone, only 72% were successful. Satisfaction was highest with the doctor visit (satisfaction=79, on a scale of 1-100) and lowest with telephone registration (satisfaction = 59). Preventive health care screening was generally disappointing, particularly for Papanicolaou smear and clinical breast examination, although frequent users of a clinic (with more opportunities for screening) generally had higher rates of screening. CONCLUSION: We demonstrated the feasibility of constructing indicators of multiple dimensions of the quality of outpatient care using patient-reported information. Quality dimensions captured by survey included access, patient experience and clinical quality. Results were successfully summarized in easy to read and understand formats for clinic managers and city health department officials.     

肝动脉栓塞化疗对原发性肝癌患者肝纤维化指标的影响

为探讨重复肝动脉化疗（TAE）对原发性肝癌（PHC）患者肝脏损伤的影响,对40例经3次TAE治疗的PHC患者和25例肝血管瘤患者（经1次TAE治疗）测定治疗前后透明质酸（HA）,层粘连蛋白（LN）,人Ⅲ型前胶原（HpcⅢ）和Ⅳ型胶原（Ⅳ·C）的含量。结果发现第2次TAE治疗后,上述4项指标TAE前后均有显著性差异（P＜0．05）,以第3次TAE后升高最为明显（P＜0．01）。提示重复TAE治疗常可加重PHC患者的肝损害,应引起足够的重视。     

卟啉生物化学研究概况

本文在卟啉的化学结构和分类、化学检测方法、化学合成以及卟啉生物合成等方面对卟啉生物化学的研究概况进行综述。     

The use of chemical restraint in helicopter transport

Introduction: Helicopter transport of the combative patient is a major safety hazard facing air medical teams. Although physical restraints alone are helpful, the addition of chemical restraint (CR) often is necessary to control these patients while in flight.

Methods: A survey was conducted to determine the current practices of using nonparalyzing CR in air medical transport programs nationwide. The survey consisted of 24 questions on the use of CR during transport. Each U.S. program belonging to the Association of Air Medical Services was contacted by telephone, and a flight nurse or paramedic provided answers based on personal experience and statistics compiled by his or her individual program.

Results: Of the 100 programs responding, benzodiazepines were used most commonly to control agitation with 51% using midazolam. Patients with a head injury required CR more frequently than any other condition (73%). Crews flying larger aircraft reported less need for CR. A physician order was required by only 30% of the programs, but delays infrequently endangered the patient (2%). Only 7% of the responding programs had a patient whose condition deteriorated because of CR.

Conclusion: CR is necessary in air medical transport. Most programs use short-acting benzodiazepines. Crews in smaller aircraft use CR more frequently, and head injury is the most common condition requiring such restraint.     

季铵盐消毒剂中检出一株洋葱假单胞菌

目的　观察从复合季铵盐消毒剂中分离得到的洋葱假单胞菌对常用消毒剂的抗力。方法　以常用的氯和戊二醛消毒剂对其进行杀菌试验,并与对大肠杆菌和金黄色葡萄球菌相应的杀菌效果进行比较,以除菌后污染样液对大肠杆菌、金黄色葡萄球菌进行了杀菌试验和ＨＢｓＡｇ 抗原性破坏试验,对芽胞和白色念珠菌进行抑菌试验。结果　该洋葱假单胞菌对氯和戊二醛的抗力与大肠杆菌和金黄色葡萄球菌接近,污染样液除菌后１ ０００ 倍稀释对大肠杆菌和金黄色葡萄球菌仍有较好的杀菌效果,２０ 倍稀释可完全破坏ＨＢｓＡｇ 抗原性,和抑制枯草杆菌黑色变种芽胞的生长,１ ６００ 倍稀释可抑制白色念珠菌生长,而原液则不能抑制分离菌株的生长。结论　洋葱假单胞菌可在高浓度（１ ．６％ ）季铵盐消毒剂中大量生长,其对该类消毒剂抗力明显高于大肠杆菌、金黄色葡萄球菌、白色念珠菌、枯草杆菌黑色变种芽胞和ＨＢｓＡｇ,其对氯和戊二醛的抗力与大肠杆菌和金黄色葡萄球菌接近     

Occupational induction of hypersensitivity after an accidental exposure to chloromethylisothiazolinone and methylisothiazolinone (CMI/MI) in an industrial worker.

A process worker in a paper chemical plant developed an immediate local dermal irritation and delayed bullous dermatitis due to induction of hypersensitivity following an accidental exposure to chloromethylisothiazolinone and methylisothiazolinone (CMI/MI) biocide. Contact allergy to the isothiazolinone mixture was confirmed by skin patch testing. The dermatitis healed in four weeks, and the worker was advised to avoid all CMI/MI containing products. In a one-year follow-up he did not present with any further skin symptoms. Preventive measures are important for avoiding induction of hypersensitivity to concentrated CMI/MI solutions in industrial workers.     

分子流行病学在职业性致癌研究中的应用

作者综合描述了分子流行病学基本概念的主要内容与传统流行病学的差异。阐明：１．分子流行病学是分子生物学与流行病学相结合的边缘科学;２．化学致癌物在体内的生成量及其与生物大分子结合的生物有效量与癌症发生有关;３．染色体异常综合症是癌症早期的生物效应;癌基因激活,抗癌基因失活是被启动了的细胞恶性转化所必须的;４．先天和后天获得的宿主因素可影响人体对致癌剂的易感性;５．建立生物样品库,进行前瞻队列研究可提供连续性观察结果及癌前癌后比较,为因果关系的时间顺序提供有效的依据     

妇科癌症病人化疗期间呕吐的心理疗法

目的呕吐是癌症患化疗期间常见的症状之一,频繁的呕吐不仅给患带来痛苦,而且影响生活质量,甚至迫使患中止化疗;方法对100例妇科癌症病人采取有效的。理疗法或。理疗法加药物疗法;结果呕吐的发生率与单纯应用止吐药物患相比P<0．05,差异有显性;结论妇科癌症病人化疗期间呕吐的B理疗法或B理疗法结合药物疗法明显强于单纯药物疗法。