Sensible approaches to avoid needle stick accidents in nuclear medicine

OBJECTIVE: Needle sticks are a continuous concern in the health care environment because of the prevalence of bloodborne pathogens in today's society. Radioactive contamination is another concern with needle sticks during nuclear medicine and nuclear pharmacy procedures. In our institution, substantial efforts have been made to prevent needle sticks, but they still occur occasionally. The purpose of this project was to analyze different practices and products to determine the best protocol in an effort to avoid further needle sticks. METHODS: The nuclear medicine technologists were surveyed to determine how many needle sticks have occurred and the situation behind each occurrence. Using our initial survey, the circumstances involved in each incident were reviewed, suggestions considered, and various means of protection analyzed. Five options were presented in a second survey. RESULTS: The results of the second survey showed that technologists favored the newly designed needle-capping blocks for preventing needle sticks in their daily routine procedures. CONCLUSION: The newly designed needle-capping block is best suited for both nuclear medicine and nuclear pharmacy laboratories. We will continue to monitor the effectiveness of this new approach in preventing needle sticks.     

Comparison of flomoxef with latamoxef in the treatment of sepsis and/or Gram-negative bacteremia in adult patients

The safety and efficacy of flomoxef and latamoxef were compared in the treatment of hospitalized patients with sepsis and/or Gram-negative bacteremia in a prospective, open-labelled clinical trial. Patients were randomized to receive 1 to 2 g intravenous doses of either flomoxef every 6 to 12 h, or latamoxef every 8 to 12 h. Data from 21 patients given flomoxef and 23 patients given latamoxef were included in the evaluation of efficacy. Flomoxef produced clinical cure and satisfactory microbiological responses in 85.7% and 100% of patients, respectively. These results were similar to those obtained with latamoxef (87% and 100%, respectively). In addition, no significant difference was found in mean age, sex, severity of infection, distribution of pathogens and focus of infection between the two groups. However, the flomoxef group included more patients with ultimately fatal diseases. Six patients given flomoxef and two patients given latamoxef developed superinfections caused by yeast, enterococci and Pseudomonas aeruginosa in the urinary tract. Mild and reversible adverse reactions probably related to flomoxef and latamoxef were noted in 14.3% and 13% of patients, respectively. The results of this study demonstrated that flomoxef is a safe and effective antimicrobial agent in the treatment of patients with sepsis and/or Gram-negative bacteremia.     

Growth suppression of low HER-2/neu-expressing breast cancer cell line MDA-MB-435 by tyrosine kinase inhibitor emodin

The tyrosine kinase inhibitor emodin (3-methyl-1,6,8-tridroxyanthaquinone) is known to preferentially suppress the growth of the HER-2/neu-overexpressing breast cancer cell line. In this study, emodin effectively suppressed growth of MDA-MB-435, a breast cancer cell line with low HER-2/neu expression. Since emodin is a tyrosine kinase inhibitor, we questioned whether another tyrosine kinase might play a role in the tumorigenicity of MDA-MB-435. By Western blotting with anti-phosphotyrosine antibody, we detected a 72-kDa protein which is uniquely phosphorylated on tyrosine in MDA-MB-435. The level of phosphotyrosine in the 72-kDa protein was significantly reduced by treatment with emodin. This suggests that a strong tyrosine kinase may reside in MDA-MB-435 and the 72-kDa protein serves as a substrate for the tyrosine kinase.     

Comparative absorption kinetics of intramuscular midazolam and diazepam

Purpose

This study investigates the rate and extent of absorption following intramuscular injection of midazolam and diazepam.

Methods

Four healthy male volunteers were recruited in this randomized three-way cross-over study. On one occasion each subject received simultaneous im injections of 5 mg midazolam and 10 mg diazepam in separate deltoid muscles. On two other separate occasions each subject received an iv infusion of 7.5 mg midazolam and 30 mg diazepam over five minutes. Frequent arterial blood samples were collected for up to two hours and venous blood samples were collected for up to 24 hours for midazolam and ten days for diazepam. A gas chromatography assay was used to determine the plasma concentrations of midazolam and diazepam. The im absorption profiles were estimated using constrained least-squares deconvolution.

Results

There were substantial intersubject variabilities in the estimated pharmacokinetic parameters (volumes and clearances) of intravenous midazolam and diazepam. The mean (±sd) time to peak plasma concentration (C_max) was shorter for im midazolam (17.5 ± 6.5 min) relative to diazepam (33.8 ± 7.5 min). The mean (+sd) time to peak absorption rate was also shorter for midazolam (9 ± 2 vs 13.8 ± 7.5 min). The peak rate of absorption was identical (0.18 mg · min^?1) and bioavailability was 1.0 for both drugs.

Conclusions

We conclude that midazolam has more rapid absorption than diazepam following im administration.     

Increased reactive oxygen species in familial amyotrophic lateral sclerosis with mutations in SOD1

Amyotrophic lateral sclerosis (ALS) is a paralytic disorder characterized by degeneration of large motor neurons of the brain and spinal cord. A subset of ALS is inherited (familial ALS, FALS) and is associated with more than 70 different mutations in the SOD1 gene. Here we report that lymphoblast cell lines derived from FALS patients with 16 different mutations in SOD1 gene exhibit significant increase of intracellular reactive oxygen species (ROS) compared with sporadic ALS (SALS) and normal controls (spouses of ALS patients). The ROS generation did not correlate with SOD1 activity. Further, cells incubated with vitamin C, catalase or the flavinoid quercetin significantly reduced ROS in all groups. The catalase inhibitor 3-amino-1,2,4-triazole resulted in a ten-fold increase of ROS in all groups. Neither L-nitroarginine, a nitric oxide synthase inhibitor or vitamin E altered the ROS levels. Thus, these studies suggest that hydrogen peroxide (H(2)O(2)) is a major ROS elevated in FALS lymphoblasts and it may contribute to the degeneration of susceptible cells. Further, we postulate a mechanism by which increased H(2)O(2) could be generated by mutant SOD1.     

The surgical treatment for degenerative disease of the ankle

Although a variety of surgical techniques are available for the surgical treatment of early degenerative disease of the ankle, arthrodesis remains the preferred treatment for severe cases. We studied 126 ankles with an average follow up of 39 months of whom 25 with early disease underwent debridement and cheilectomy, 18 with intermediate disease underwent lower tibial osteotomy and 83 with severe disease underwent either arthrodesis (78) or total ankle replacement (5). In 96% of cases there was a satisfactory functional outcome.     

Characteristics of optic disc changes in Taiwanese patients with primary angle-closure glaucoma.

BACKGROUND AND PURPOSE: Primary angle-closure glaucoma (PACG) is the predominant form of glaucoma among Asians. Although numerous studies have been done to describe the characteristic optic disc changes in patients with primary open angle glaucoma (POAG) which is the predominant form of glaucoma among Western populations, few studies have evaluated the optic disc changes in patients with PACG. The aim of this study was to elucidate the characteristic intrapapillary and parapapillary disc changes in PACG in a cross-sectional study and to develop a practical approach to the detection of glaucomatous optic disc changes in PACG by ophthalmoscopic examination. METHODS: A total of 103 eyes in 103 PACG patients were studied. Forty one eyes of 41 age- and sex-matched healthy subjects served as controls. Three glaucoma-trained subspecialists examined stereophotographs of optic discs to evaluate the intrapapillary and parapapillary changes. The differences in PACG and control group eyes were compared. RESULTS: Concentric steep enlargement of the optic disc was found in 99 PACG eyes (96%). Local notching was noted in only 3 eyes, and vertically oval-shaped cupping of the optic disc in only 1 eye. Disc hemorrhage was not detected in any eye. Parapapillary atrophy of the alpha zone involving both temporal and nasal side of the optic disc and parapapillary atrophy of beta zone were significantly more frequent in the PACG group. The presence of an alpha zone or a beta zone simultaneously involving both the temporal and nasal side of the optic disc was associated with more severe optic nerve head damage. CONCLUSIONS: The intrapapillary change in the PACG group eyes reflected the development of cupping in PACG patients with small and compact optic discs. The parapapillary atrophy paralleled the intrapapillary optic disc cupping in eyes of the PACG group.     

A novel conotoxin inhibiting vertebrate voltage-sensitive potassium channels.

Toxins from cone snail (Conus species) venoms are multiple disulfide bonded peptides. Based on their pharmacological target (ion channels, receptors) and their disulfide pattern, they have been classified into several toxin families and superfamilies. Here, we report a new conotoxin, which is the first member of a structurally new superfamily of Conus peptides and the first conotoxin affecting vertebrate K+ channels. The new toxin, designated conotoxin ViTx, has been isolated from the venom of Conus virgo and comprises a single chain of 35 amino acids cross-linked by four disulfide bridges. Its amino acid sequence (SRCFPPGIYCTSYLPCCWGICCSTCRNVCHLRIGK) was partially determined by Edman degradation and deduced from the nucleotide sequence of the toxin cDNA. Nucleic acid sequencing also revealed a prepropeptide comprising 67 amino acid residues and demonstrated a posttranslational modification of the protein by releasing a six-residue peptide from the C-terminal. Voltage clamp studies on various ion channels indicated that the toxin inhibits the vertebrate K+ channels Kv1.1 and Kv1.3 but not Kv1.2. The chemically synthesized product exhibited the same physiological activity and identical molecular mass (3933.7 Da) as the native toxin.