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In vivo diagnosis with cancer-specific targeting agents that have optimal characteristics for imaging is an important development in treatment planning for cancer patients. Overexpression of the HER2 antigen is high in several types of carcinomas and has predictive and prognostic value, especially for breast cancer. A new type of targeting agent, the Affibody molecule, was described recently. An Affibody dimer, His6-(ZHER2:4)2 (15.4 kDa), binds to HER2 with an affinity of 3 nmol/L and might be used for the imaging of HER2 expression. The use of 99mTc might improve the availability of the labeled conjugate, and Tc(I)-carbonyl chemistry enables the site-specific labeling of the histidine tag on the Affibody molecule. The goals of the present study were to prepare 99mTc-labeled His6-(ZHER2:4)2 and to evaluate its targeting properties compared with the targeting properties of 125I-4-iodobenzoate-His6-(ZHER2:4)2 [125I-His6-(ZHER2:4)2]. METHODS: The labeling of His6-(ZHER2:4)2 with 99mTc was performed with an IsoLink kit. The specificity of 99mTc-His6-(ZHER2:4)2 binding to HER2 was evaluated in vitro with SK-OV-3 ovarian carcinoma cells. The comparative biodistributions of 99mTc-His6-(ZHER2:4)2 and 125I-His6-(ZHER2:4)2 in tumor-bearing BALB/c nu/nu mice were determined. RESULTS: The labeling yield for 99mTc-His6-(ZHER2:4)2 was approximately 60% (50 degrees C), and the radiochemical purity was greater than 97%. The conjugate was stable during storage and under histidine and cysteine challenges and demonstrated receptor-specific binding. The biodistribution study demonstrated tumor-specific uptake levels (percentage injected activity per gram of tissue [%IA/g]) of 2.6 %IA/g for 99mTc-His6-(ZHER2:4)2 and 2.3 %IA/g for 125I-His6-(ZHER2:4)2 at 4 h after injection. Both conjugates provided clear imaging of SK-OV-3 xenografts at 6 h after injection. The tumor-to-nontumor ratios were much more favorable for the radioiodinated Affibody. CONCLUSION: The use of Tc(I)-carbonyl chemistry enabled us to prepare a stable, site-specifically labeled 99mTc-His6-(ZHER2:4)2 conjugate that was able to bind to HER2-expressing cells in vitro and in vivo. The indirectly radioiodinated conjugate provided better tumor-to-liver ratios. The labeling of Affibody molecules with 99mTc should be investigated further.  相似文献   
64.
Synkinesias secondary to nerve lesions and aberrant re-innervation are well-known phenomena especially after lesions of the facial nerve. Synkinesias can successfully be treated with botulinum toxin A (BTx A). Synkinesias of the cremaster muscle have not been described or treated to date. We present the case of a 62-year-old man who developed synkinesias of both cremaster muscles after extensive laparatomy for esophageal cancer. Treatment of synkinesias with various oral medications had been unsuccessful. Electromyography-guided injections of BTx A in both cremaster muscles (15 MU on the right and 10 on the left) led to significant symptom relief for an average of 8 weeks. We present the case including pre- and posttreatment video clips.  相似文献   
65.
OBJECTIVE: This study investigated auditory involuntary and voluntary attention in children aged 6-8, 10-12 and young adults. The strength of distracting stimuli (20% and 5% pitch changes) and the amount of allocation of attention were varied. METHODS: In an auditory distraction paradigm event-related potentials (ERPs) and behavioral data were measured from subjects either performing a sound duration discrimination task or watching a silent video. RESULTS: Pitch changed sounds caused prolonged reaction times and decreased hit rates in all age groups. Larger distractors (20%) caused stronger distraction in children, but not in adults. The amplitudes of mismatch negativity (MMN), P3a, and reorienting negativity (RON) were modulated by age and by voluntary attention. P3a was additionally affected by distractor strength. Maturational changes were also observed in the amplitudes of P1 (decreasing with age) and N1 (increasing with age). P2-modulation by voluntary attention was opposite in young children and adults. CONCLUSIONS: Results suggest quantitative and qualitative changes in auditory voluntary and involuntary attention and distraction during development. The processing steps involved in distraction (pre-attentive change detection, attention switch, reorienting) are functional in children aged 6-8 but reveal characteristic differences to those of young adults. In general, distractibility as indicated by behavioral and ERP measures decreases from childhood to adulthood. SIGNIFICANCE: Behavioral and ERP markers for different processing stages involved in voluntary and involuntary attention reveal characteristic developmental changes from childhood to young adulthood.  相似文献   
66.
OBJECTIVE: Although the clinical course of Alzheimer disease (AD) is gradual, it is useful for a number of reasons to distinguish between different levels of severity. The Clinical Dementia Rating (CDR) has demonstrated high validity and reliability for this purpose, but it requires a considerable amount of data to be collected both from the patient and from an informant. In the present study, the authors mapped Mini-Mental State Examination (MMSE) scores onto CDR categories to determine how well the MMSE performs as a surrogate of the CDR as a timesaving method of staging dementia. METHOD: Eight hundred sixty-three probands, including 524 patients with probable AD, 92 patients with questionable dementia, and 247 with memory complaints but no objective cognitive impairment, were included. Cutoff scores were identified on one-half of the sample using a receiver operating characteristic analysis. The cutoff values were then applied to the other half of the sample, and the agreement between MMSE score ranges and CDR stages was determined by calculating Cohen's kappa. RESULTS: The MMSE discriminated well between CDR stages 0.5, 1, 2, and 3 but performed poorly in the separation between CDR stages zero and 0.5. The MMSE ranges were 30 for no, 26-29 for questionable, 21-25 for mild, 11-20 for moderate, and 0-10 for severe dementia. Substantial agreement between the two instruments was obtained for the categories mild (kappa=0.62, p<0.001, N=115), moderate (kappa=0.69, p<0.001, N=114), and severe dementia (kappa=0.76, p<0.001, N=39), whereas the agreement was moderate for no (kappa=0.44, p<0.001, N=120) and only fair for questionable dementia (kappa=0.28, p<0.001, N=42). CONCLUSION: The MMSE can be used as a surrogate measure for the CDR for the staging of dementia in AD.  相似文献   
67.
Sir, Metformin has been used for many decades as an effective glucose-loweringmedication in the treatment of type 2 diabetes mellitus. Recentstudies clearly demonstrated that metformin reduced secondarycomplications of diabetes mellitus type 2 without promotingweight gain, which is in contrast to treatment with insulinand/or sulphonylurea [1]. Lactic acidosis is a serious sideeffect observed with metformin treatment and  相似文献   
68.
Abdominal infection has the fifth highest incidence of all posttraumatic infections but has the second highest mortality rate with 25%,pneumonia,with 29%, being the only posttraumatic infection that is more frequently lethal.Posttraumatic abdominal sepsis, on the other hand, has a mortality rate of almost 50%.This rate cannot be reduced except by prompt identification of the correct diagnosis of the underlying injury or complication.This means that delayed laparotomy is strikingly detrimental in these patients, with 46% mortality as opposed to 11% in patients who undergo laparotomy promptly. In parallel with this, the mortality of fresh-onset and localized peritonitis is 14%,whereas that of diffuse purulent peritonitis is up to a devastating 42%.  相似文献   
69.
Malunion and nonunion after fracture present many difficulties in trauma surgery. Selection of the best therapy and operative techique requires careful analysis of the complications. Hyperthrophic nonunion of the femur shaft is mostly best treated with locking reamed nails. Significant differences in torsions after nailing can be corrected by repositioning of the distal interlocking screws if recognized sufficiently early. After fracture healing an open rotation osteotomy is necessary; stabilization can be achieved by means of medullary nails or a condylar plate. How a malalignment of the bone axis is corrected depends on the position of a malunion, the functional deficit caused, and the biomechanical demands on the joint. Condylar plates can often solve the problems in this region. There are also guidelines for ¶the treatment of atrophic and infected nonunions (recommended procedures are ¶aggressive debridement, autologous cancellous bone graft, and biological osteosynthesis), but the treatment of individual cases requires a exhaustive knowledge of and experience in this special field. It is quite common for even well-established procedures to fail. When the bone is biologically reduced and this is the reason for malunion newly developed techniques of internal fixation can be applied. The less invasive stabilization system (LISS), combined with autologous cancellous bone grafting if necessary, can result in healing even in a worst-case scenario.  相似文献   
70.
Influenza A was cultured in 62 double rooms. The roommate was infected in 12 (19.4%). During 3,294 resident-seasons, influenza was cultured in 208 single rooms (6.3%). Those who lived in double rooms with a culture-positive roommate had a 3.07 relative risk (CI95, 1.61-5.78) of acquiring influenza.  相似文献   
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