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Purpose

The aim was to investigate the stability of cefazolin in elastomeric infusion devices.

Methods

Elastomeric devices (Infusor LV) that contain cefazolin (3 g/240 mL and 6 g/240 mL) were prepared and stored at 4°C for 72 hours and then at 35°C for 12 hours, followed by 25°C for 12 hours. An aliquot was withdrawn at predefined time points and analyzed for the concentration of cefazolin. Samples were also assessed for changes in pH, solution color, and particle content.

Findings

Cefazolin retained acceptable chemical and physical stability over the studied storage period and conditions.

Implications

These findings will allow the administration of cefazolin by the Infusor LV elastomeric device in the outpatient and remote settings.  相似文献   
14.
Thyrotoxicosis is associated with a high-turnover osteoporosis, which has been solely attributed to elevated thyroid hormone levels. Mice lacking the thyroid hormone receptors α and β establish a role for thyroid hormones in regulating bone remodeling. We show that TSH, which falls when thyroid hormones rise, directly suppresses bone remodeling, and that TSH receptor null mice have profound bone loss. We suggest that reduced TSH signaling contributes to hyperthyroid osteoporosis and that TSH and its receptor could become valuable drug targets.  相似文献   
15.
Over 8,400 pretreatment isolates of Neisseria gonorrhoeae collected in the United States between November 1972 and April 1975 were tested for their in vitro resistance to penicillin, ampicillin, tetracycline, and spectinomycin. Trends and seasonality of resistance were examined by use of a harmonic regression technique. During the study period, there was a significant difference among years in the mean minimal inhibitory concentrations (MICs) for each antibiotic (P less than 0.001 for penicillin, ampicillin, and tetracycline; P less 0.05 for spectinomycin), and the mean MIC for each antibiotic decreased. Resistance to tetracycline and penicillin was highest in the winter months. Seasonality of resistance, alone or as an interaction with year, approached significance (P less than 0.10) or was significant (P less than 0.05) for all four antibiotics.  相似文献   
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Background:

Hepatitis C Virus (HCV) is a major causative agent for chronic liver disease worldwide. Hepatic steatosis is a frequent histological feature in patients with chronic HCV. Both host and viral factors are involved in steatosis development. It results from uncontrolled growth of cytoplasmic lipid droplets (LDs) in hepatocytes. LDs are intracellular organelles playing key role in the HCV life cycle. HCV core protein localizes at the LD surface and this localization is crucial for virion production.

Objectives:

We explored in vitro interplay of core and LDs to investigate the role of core in steatosis.

Materials and Methods:

Core expression vectors were transfected in Huh-7 cells. The effect of core protein on LDs content and distribution in the cells was monitored by confocal microscopy. Cells were treated with oleic acid to analyze the effect of increased intracellular LDs on core expression. Core protein expression was monitored by western blot analysis.

Results:

Core expression altered the intracellular lipid metabolism, which resulted in a change in LDs morphology. Core LDs interaction was required for this effect since the mutation of two prolines (P138A, P143A), which impair LDs localization, had no impact on LDs morphology. Conversely, oleic acid induced intracellular LD content resulted in increased core expression.

Conclusions:

Core-LDs interaction may be an underlying molecular mechanism to induce liver steatosis in patients with HCV infection. This interaction is also crucial for efficient viral replication and persistence in infected cells. Steatosis can also interfere with efficient standard interferon therapy treatment. Management of steatosis should be considered along with standard care for achieving higher sustained virological response (SVR) in patients receiving interferon regimen.  相似文献   
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Abstract

Context

Spinal arachnoiditis is a rare disease caused by fibrosis and adhesion of the arachnoid membrane due to chronic inflammation. The causes of arachnoiditis are infection, spinal surgery, intraspinal injection of steroid or myelography dye, and spinal anesthesia.

Method

Case report.

Findings

A 60-year-old woman presented with progressive weakness and sensory change of both legs and urinary symptoms. She had received a single caudal block 6 months before symptom onset. Magnetic resonance imaging of the thoraco-lumbar spine showed an intradural extramedullary tumor at the T5–T7 level. She underwent laminectomy and tumor resection. The pathological finding was arachnoiditis. After surgery, a rehabilitation program of strengthening exercises of both lower extremities and gait training was started. At 2-month follow-up, she was able to walk with orthoses and performed daily activities with minimal assistance.

Conclusion

Symptoms of spinal arachnoiditis occurred 6 months after a single caudal block in this woman. Clinicians should be aware of this possible delayed complication.  相似文献   
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