Importance of an immunodominant surface-exposed loop on outer membrane protein P2 of nontypeable Haemophilus influenzae.

Nontypeable Haemophilus influenzae (NTHI) frequently causes recurrent infections of the respiratory tract in humans. Previous indirect evidence suggested that a strain-specific immune response occurs following infection and that this immune response is directed at an immunodominant epitope on the bacterial surface. To test this hypothesis, mice and rabbits were immunized with whole cells of a strain of NTHI and the antiserum was characterized to identify the antigens to which antibodies were directed. All animals made a prominent antibody response to the loop 5 region of the P2 molecule, which is the major outer membrane protein. Rabbit serum showed complement-dependent bactericidal activity. Adsorption of the immune serum with the loop 5 fusion peptide removed bactericidal activity and also abolished reactivity to P2 detected by an immunoblot assay, an enzyme-linked immunosorbent assay, and a radioimmunoprecipitation assay. These data indicate that immunization with whole cells of NTHI results in a prominent antibody response which is directed at epitopes on the loop 5 region of the P2 molecule. Thus, a strain-specific immune response to NTHI occurs as a result of the expression of an immunodominant epitope on the P2 molecule.     

牙源性脓肿标本中的产黑色素类杆菌群菌株分离鉴定

本文对４４例牙源性脓肿（尖周脓肿２４例，牙周脓肿１２例，冠周脓肿８例）脓液标本中的产黑色素类杆菌群菌株进行分离、培养、鉴定。其中３８例存在产黑菌群，以中间型类杆菌阳性率最高。牙龈类杆菌在牙周脓肿中检出率最高。２４例尖周脓肿可分离出６株牙髓类杆菌而其它两种牙源性脓肿则无牙髓类杆菌，推测该菌与牙髓尖周感染的病理过程有关。     

Identification of Leishmania donovani isolates from different kala-azar foci in China by kDNA hybridization.

kDNA sequence homology of Leishmania donovani isolates from three types of kala-azar foci in China were analyzed by using dot and Southern hybridization with biotin- and 32P-labelled probes. The results revealed kDNA sequence heterogeneity among Leishmania donovani isolates from the three kala-azar foci: sequence homology between isolates of hill and desert foci was higher than that between hill and plain foci isolates. The kDNA hybridization technique was also found to be specific and sensitive for direct identification of Leishmania in animal tissues. In a preliminary survey, kDNA hybridization of cutaneous tissue blots of 71 dogs from endemic regions showed a positive rate of 40.8%, and the rate of double positive cases (touch blot hybridization and bone marrow smear) reached 91.3%. The direct identification of Leishmania in tissues by kDNA hybridization seems to be a useful and convenient method for epidemiological study and clinical diagnosis, especially for species/strain characterization.     

单片机自动灌流系统设计及其医学应用

介绍一种用单片机构成的自动灌流控制系统。它以灌流压为控制指标，以ＬＤＢ－Ｍ电子蠕动泵作为执行机构，构成闭环控制系统，能实现用户设定的各种液流压曲线。系统内采用了ＥＥＰＲＯＭ存储器，可对用户设定的多达１０条灌流曲线进行长期保存。     

选择性髂内动脉结扎与栓塞对盆腔血供的影响

目的：旨在探讨选择性髂内动脉结扎与栓塞两种方法对盆腔血供的影响。方法：将两组犬在膀胱上动脉分支以下之髂内动脉分别行结扎与栓塞，对比观察两组膀胱创面出血、盆腔动脉造影及盆腔脏器组织学变化，以确定其盆腔脏器的血供情况。结果：①结扎组膀胱创面出血明显大于栓塞组；②结扎组髂内动脉侧支循环建立时间明显早于且数目多于栓塞组；③两组盆腔脏器均未见缺血坏死。结论：栓塞组阻断髂内动脉侧支循环的数目多于结扎组，故对盆腔血供的影响大于结扎组。避免髂内动脉阻断范围过广可减少盆腔脏器缺血坏死的机会。     

Association of low caregiver health literacy with reported use of nonstandardized dosing instruments and lack of knowledge of weight-based dosing.

OBJECTIVE: Caregivers of young children frequently measure doses of liquid medications incorrectly. Use of nonstandardized dosing instruments and lack of knowledge that dosing is weight-based contribute to dosing errors. We sought to assess whether low caregiver health literacy was associated with these outcomes. METHODS: This was a cross-sectional analysis of caregivers presenting to an urban pediatric emergency room. Dependent variables were caregiver reported use of nonstandardized dosing tools and knowledge of weight-based dosing. The independent variable was caregiver health literacy (Test of Functional Health Literacy in Adults [TOFHLA]). RESULTS: Two hundred ninety-two caregivers were assessed: 23.3% reported use of nonstandardized liquid dosing instruments, and 67.8% were unaware of weight-based dosing. Caregivers who were unaware of weight-based dosing were more likely to use nonstandardized dosing tools (28.3% vs 12.8%; P = .003). In unadjusted analyses, overall health literacy, reading comprehension, and numeracy were all associated with both dependent variables. In analyses adjusting for child age, health care experiences, and caregiver acculturation and education, inadequate/marginal overall health literacy was associated with lack of knowledge of weight-based dosing (adjusted odds ratio [AOR] 2.3; P = .03), whereas lower reading comprehension was associated with both lack of knowledge (AOR 2.0; P = .03) and reported use of nonstandardized instrument (AOR 2.4; P = .007). CONCLUSIONS: Low health literacy, in particular reading comprehension, was associated with reported use of nonstandardized dosing instruments and lack of knowledge regarding weight-based dosing. Both caregiver health literacy and sociodemographic factors should be considered in the design of interventions to prevent medication administration errors.     

In vitro evaluation of ablation parameters of normal and fibrous aorta using smooth excimer laser coronary angioplasty

A modified exeimer laser energy delivery system was used to irradiate 100 segments of normal and fibrous aorta in vitro. The laser beam was scanned into 8 fiber bundles consisting of 50 fibers each resulting in a reduction of the applied pulse energy. The total repetition rate was increased to 150 Hz in order to keep the repetition rate per fiber bundle close to 20 Hz and to minimize thermal injury. The results demonstrate that effective ablation (etch rate per 8 pulses > 2.0 μm) occurred at an energy fluency of 50 mJ/mm² in both normal and fibrous aorta. Tissue damage (carbonization, tissue separation, fissures, cracks, and vacuolization) was in a range of 100 ± 28 to 152 ± 30 μm for normal aorta and in a range of 57 ± 35 to 110 ± 39 μm for fibrous aorta. We conclude that effective ablation of normal and fibrous human aorta can be achieved by the application of smooth excimer laser coronary angioplasty. This improvement of excimer laser technology may result in a reduction of shock wave- and cavitation-induced damage leading to a reduction of tissue injury. However, this awaits further in vitro and in vivo confirmation. © 1993 Wiley-Liss, Inc.     

Optical Pretargeting of Tumor with Fluorescent MORF Oligomers

Objective Pretargeting with radioactivity has significantly improved tumor to normal tissue radioactivity ratios over conventional antibody imaging in both animal studies and clinical trials. This laboratory is investigating DNA analogues such as phosphorodiamidate morpholinos (MORFs) for pretargeting using technetium-99m (^99mTc) for detection. However, the unique properties of fluorescence activation and quenching combined with oligomers with their unique properties of hybridization may be particularly useful when used together for pretargeting with optical detection. The use of linear fluorophore-conjugated oligomer duplexes have been little used in animals, and to our knowledge, have not previously been considered for pretargeting applications. Methods A MORF/cDNA pair was selected such that when hybridized, the fluorescence of the Cy5.5-conjugated 25 mer MORF (Cy5.5–MORF25) is inhibited with a BHQ3-conjugated 18 mer complementary DNA (BHQ3–cDNA18). The short BHQ3–cDNA18 was selected to dissociate in the presence of a long cMORF25 in the pretargeted tumor, thus releasing the inhibitor from the Cy5.5 emitter. In this manner, the Cy5.5 fluorescence will be inhibited everywhere but in the target. The dissociation was first examined in vitro by adding the duplex to the cMORF25 both in solution and immobilized on polystyrene microspheres and by surface plasmon resonance (SPR). Thereafter, biotinylated cMORF25 immobilized on streptavidin polystyrene microspheres were administered intramuscularly in one thigh of hairless SKH-1 mice as target while an identical weight of the identical microspheres but without the cMORF25 was administered in the contralateral thigh as control. The animals then received IV the Cy5.5–MORF25/BHQ3–cDNA18 duplex or equal molar dosage of single-chain Cy5.5–MORF25 and were imaged. Results The SPR studies showed that the immobilized cDNA18 rapidly captured the flowing MORF25 to provide a duplex with a slow dissociation rate constant. Furthermore, when cMORF25 was next allowed to flow over the now immobilized duplex, the cDNA18 was unable to prevent dissociation of the heteroduplex and the formation and release of the cMORF25-MORF25 homoduplex. Images of animals obtained soon after receiving the Cy5.5–MORF25 singlet showed intense whole body fluorescence obscuring the target thigh. However, only 5 minutes after receiving the Cy5.5–MORF25/BHQ3–cDNA18 duplex, the target thigh was clearly visible along with only the kidneys. Conclusions This first study of optical pretargeting provides a proof of concept that oligomer pretargeting found to be useful with radioactivity detection is applicable with fluorescent detection as well. In addition, our results demonstrate that by using linear oligomers for optical pretargeting, chain lengths (and base sequences) may be manipulated to provide duplexes with stabilities and fluorescence inhibition optimized for pretargeting and other in vivo applications of optical imaging.