Evaluation of the pharmacokinetics of linezolid in an obese Japanese patient

We evaluated the pharmacokinetics of linezolid in the case of an obese Japanese patient (body weight 116 kg; body mass index 37 kg/m(2)). Linezolid was administered at a dose of 600 mg by intravenous drip infusion for 60-90 min at 12-h intervals. The results showed increased clearance of linezolid and a reduced serum concentration compared to population pharmacokinetic parameters, with trough levels below the 90% minimum inhibitory concentration. However, linezolid was effective for improving lung infection and inflammation in our patient, which may be due to its particularly effective transfer into lung tissues. Linezolid undergoes slow non-enzymatic oxidation in vivo that may be increased in obese patients, and this may account for the greater clearance. Our findings are useful for the planning of linezolid therapy in obese patients.     

Development of a simple index, calf mass index, for screening for orthostatic hypotension in community-dwelling elderly

The prevalence of orthostatic hypotension (OH) among the community-dwelling elderly is high, but the head-up tilt testing in the laboratory setting is time-consuming and costly. However, an objective index for screening for OH among older people recruited from community settings has not yet been established. Therefore, this study conducted to identify factors that can reveal OH among the elderly recruited from a community setting. A total of 86 people aged ≥ 60 years underwent head-up tilt testing with beats-by-beats blood pressure measurements at Center for elderly fitness and disease/disability prevention research at Nagoya University School of Health Sciences. OH was defined a reduction in systolic blood pressure of at least 20 mmHg or in diastolic blood pressure of at least 10 mmHg within 3 min of raising the head. Associations among anthropometric measurements, fitness parameters and OH were analyzed using multiple logistic regression. Calf mass index (CMI) (OR=0.488, 95% CI; 0.32-0.743, P<0.001) and alpha-blockers (=0.078, 95% CI; 0.007-0.883, P<0.05) were related to OH. The area under the ROC curve was 74.4% (95% CI; 62.8-86.0, P<0.001) and the discriminatory CMI value was 21.2. Our findings suggest that the CMI can be used for screening for OH in the community-dwelling elderly. This information can help clinicians and health care providers working with older people to identify those at risk of OH.     

Short telomeres in an oral precancerous lesion: Q-FISH analysis of leukoplakia

J Oral Pathol Med (2012) 41 : 372–378 Objectives: A precancerous condition is a lesion that, if left untreated, leads to cancer or can be induced to become malignant. In the oral region, leukoplakia is a lesion that has been regarded as precancerous. In cases of oral carcinoma, we have frequently noticed that a type of leukoplakia histologically demonstrating hyper‐orthokeratosis and mild atypia (ortho‐keratotic dysplasia; OKD) is often associated with carcinoma, either synchronously or metachronously. Therefore, we consider OKD‐type leukoplakia to be a true precancerous lesion. Materials and Methods: In an attempt to clarify the relationship between OKD as a precancerous condition in the oral mucosa and telomere length, we estimated telomere lengths in this type of leukoplakia using quantitative fluorescence in situ hybridization, and also quantified the frequency of anaphase–telophase bridges (ATBs) in comparison with squamous cell carcinoma in situ (CIS) and the background tissues of CIS and OKD. Results: Ortho‐keratotic dysplasia was frequently associated with squamous cell carcinoma (45.0%) and showed significantly shorter telomeres than normal control epithelium, CIS, or the background of CIS or OKD. The frequency of ATBs was much higher in OKD than in control epithelium or CIS. Conclusion: Ortho‐keratotic dysplasia appears to be frequently associated with carcinoma, chromosomal instability, and excessively shortened telomeres, not only in the lesion itself but also in the surrounding background. Therefore, when this type of leukoplakia is recognized in the oral region, strict follow‐up for oral squamous cell carcinoma is necessary, focusing not only on the areas of leukoplakia, but also the surrounding background.