Antibiotic therapy: what to consider when treating geriatric patients

The epidemiology, etiology, clinical manifestations, diagnostic approach, and therapeutic choices may be quite different for infections that occur in elderly patients compared with those that occur in younger adults. Given these variables, it is essential for clinicians who care for older patients to understand how to prescribe antibiotics appropriately for this population. This article examines the unique characteristics of infections in the elderly as well as provides recommendations on the use of specific antibiotic agents commonly used to treat infections in geriatric patients.     

Personal exposure to nitrogen dioxide from indoor heaters and cooking stoves

The personal exposure to NO₂ generated from various heaters and cooking stoves were studied, using 85 university students. The students attached NO₂ filter badges to their chests or collars and wrote down the period of time for heating and cooking for 1 week. Types of heaters and smoking habits were described through a questionnaire. The urinary hydroxyproline/creatinine ratio (HOP/C) was examined as a biomarker for health effects. The outdoor NO₂ concentration during the study period was 13.5–13.7 g/m³. Smoking and the usage of electric heaters did not affect the exposure to NO₂. Exposure increased according to the length of time kerosene heaters or oil fan heaters were used. The NO₂ concentration during the heating by a kerosene heater and an oil fan heater was calculated to be 219 and 474 g/m³, respectively. The correlation between the period of cooking and personal exposure was also observed. The NO₂ levels during cooking were calculated to be 290 g/m³. Using these calculated values of NO₂ concentration, it is possible to presume the personal exposure levels from the length of time heaters and cooking stoves are used even if the subjects do not attach the filter badges. Neither smoking nor exposure to NO₂ were associated with the increase of urinary HOP/C.     

HPV16阳性宫颈非典型增生和浸润性宫颈癌组织中E6变体的研究

通过检测E6变体在HPV16阳性的宫颈非典型增生(CIN)和宫颈浸润癌(ICC)患者中的分布,研究其致癌能力.方法:用PCR和双脱氧终止荧光法检测了42例E6基因点突变及其编码氨基酸改变,统计分布差异.结果:2例(5%)为原型,40例(95% )的E6DNA序列中含有1至3个点突变,导致13类E6氨基酸残基改变,组合成17种(94%)HPV16变体.出现频率较高的4种变体在CIN和ICC病例中共同存在,分布无显著性差异(P>0.05).DNA的点突变数在CIN和ICC病例中的分布也无显著性差异(P>0.05).结论:HPV16E6的变体多于原型,但是变体和原型的致癌能力没有明显差别.     

FDG-PET for the evaluation of tumor viability after anticancer therapy

To evaluate positron emission tomography with¹⁸F-fluorodeoxy glucose (FDG-PET) as an diagnostic tool to determine tumor viability after anticancer therapy, fourteen patients were examined by FDG-PET after the end of the treatment. The lesions with residual viable tumor cells showed higher uptake of FDG than surrounding normal soft tissue. The lesions, in which tumor viability was lost or very low, showed higher uptake of FDG in four cases and similar uptake to normal soft tissue in three cases. The residual increased uptake of FDG was considered to be caused by remaining tumor cells and/or inflammatory reaction to anticancer treatment. FDG-PET after anticancer treatment should be interpreted by considering the reaction due to the treatment and the partial volume artifact of PET caused by the limited spatial resolution.     

FDG-PET for predicting the prognosis of malignant lymphoma

To evaluate the usefulness of FDG-PET as a predictor of prognosis, 34 patients with untreated malignant lymphoma in the head and neck region were studied. After FDG-PET and treatment, they were observed from 15 to 50 months. Tumors which were aggressive and resistant to treatment tended to show high uptake of FDG. The survival rate of patients with high uptake of FDG, DAR > 8, was lower than the rate of the other patients. It is considered to be useful to add FDG uptake of the tumor to other prognostic factors for predicting the prognosis.     

Effect of aspirin on the induction of apoptosis in colorectal adenocarcinoma cell-lines

Nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit experimental carcinogenesis and their use in humans has been related epidemiologically to a reduced risk of colorectal polyps and cancer, although the mechanism involved is not known. We found that aspirin triggered the death of SW948 human colorectal adenocarcinoma cells through activation of an apoptotic pathway. Exposure of SW480 and SW948 cells to 25 mu M aspirin for 5 h resulted in the detatchment of cells from the monolayer culture at 48 h. SW948 cells with continuous exposure to 25 mu M aspirin exhibited various morphological and biochemical characteristics of apoptosis, including compact patches of condensed nuclear chromatin, and DNA fragmentation. These in vitro data suggest that apoptosis may play a role in the antitumor effect of aspirin and other NSAIDs and that the induction of apoptosis may provide an attractive therapeutic target in colorectal carcinogenesis.     

Correlation between the blood supply and grade of malignancy of hepatocellular nodules associated with liver cirrhosis: evaluation by CT during intraarterial injection of contrast medium

OBJECTIVE: The purpose of this study is to evaluate the correlation between the intranodular blood supply revealed by CT during intraarterial injection of contrast medium, mainly using helical CT, and the grade of malignancy of hepatocellular nodules associated with liver cirrhosis as classified by the International Working Party of the World Congress of Gastroenterology. SUBJECTS AND METHODS: We studied 201 histologically proven nodules (101 resected and 100 biopsied nodules), including 47 low-grade dysplastic nodules (low-DNs), 56 high-grade dysplastic nodules (high-DNs), 24 well-differentiated hepatocellular carcinomas (wd-HCCs), and 74 moderately or poorly differentiated HCCs (mp-HCCs), in 139 cirrhotic patients. Findings on CT during arterial portography (n = 201) and CT during hepatic arteriography (n = 74) were reviewed and compared with the histologic diagnosis. RESULTS: CT findings were classified into four types relative to the surrounding liver: type A (isodense), type B (slightly hypodense), type C (partially hypodense), and type D (markedly hypodense) on CT during arterial portography and type I (isodense), type II (hypodense), type III (partially hyperdense), and type IV (hyperdense) on CT during hepatic arteriography. On CT during arterial portography, the distributions of each type were low-DN (n = 47 [A, n = 36; B, n = 8; C, n = 3]), high-DN (n = 56 [A, n = 18; B, n = 20; C, n = 10; D, n = 8]), wd-HCC (n = 24; [B, n = 4; C, n = 13; D, n = 7]), and mp-HCC (n = 74 [D, n = 74]). On CT during hepatic arteriography, the distributions were low-DN (n = 26 [I, n = 18; II, n = 7; III, n = 1]), high-DN (n = 19 [I, n = 6; II, n = 7; III, n = 4; IV, n = 2]), wd-HCC (n = 15 [I, n = 1; III, n = 8; IV, n = 6]), and mp-HCC (n = 14 [IV, n = 14]). We found a statistically significant correlation between the four types and the grade of malignancy of these nodules. CONCLUSION: Findings on CT during arterial portography and CT during hepatic arteriography correlated positively with histologic grading when overlap in appearance between dysplastic nodules and HCCs occurred. The concept revealed in this study can apply to diagnoses made on the basis of Doppler sonography, dynamic CT, and MR imaging.     

Breast parenchymal activity on scintimammography: Comparison between bone-seeking agents and99mTc-sestamibi

The aim of this study was to evaluate breast parenchymal activity on scintimammography with bone-seeking agents and 99mTc-MIBI. Scintimammography was performed with bone-seeking agents in 61 patients and with 99mTc-MIBI in 33 patients. Activity in the breast parenchyma contralateral to the suspected lesion was visually assessed by two independent observers. Increased breast parenchymal activity was shown in 19 of 61 patients examined with bone-seeking agents, while it was demonstrated in only two of 33 patients examined with 99mTc-MIBI. Breast parenchymal activity of bone-seeking agents was higher in patients aged 50 years or younger than in those older than 50. Increased parenchymal activity of bone-seeking agents may disturb visualization of primary breast cancer especially in relatively young patients. Low parenchymal activity is suggested to be a favorable characteristic of 99mTc-MIBI as a scintimammographic agent.     

Bone Metastases from Soft Tissue Sarcomas

The incidence, distribution, time of appearance, and radiologic findings of bone metastases from soft tissue sarcomas, exclusive of lymphomas, were evaluated in 320 patients with soft tissue sarcomas. Thirty patients (9.4%) had evidence of 58 bone metastases. Five of 30 patients presented with metastases, and 25 of 30 patients developed metastases up to 66 months after presentation with a mean time interval of 21.3 months. The incidence of skeletal metastases differed among histologic subtypes of sarcomas; alveolar soft part sarcoma (5 of 8), dedifferentiated liposarcoma (2 of 4), angiosarcoma (2 of 4), and rhabdomyosarcoma (5 of 16) tended to show a higher incidence of bone metastases. The sarcomas metastasized to the regional bones close to the primary tumor in 16 (53%) of 30 patients and to the axial bones in 18 (60%). On conventional radiographs, the osseous metastases demonstrated predominantly osteolytic changes, and evidence of pathological fracture was observed in 31% of 58 metastases.