Unusual analytical interference caused by benzathine penicillin G

Benzathine penicillin G is one of the antibiotics most often used in ENT practice. In spite of potential allergic or hypersensitivity complications, the restrictions for its administration are scant and its antibacterial spectrum often coincides with the pathogenic flora of the upper airways. A curious analytical interference secondary to its use was detected in two patients seen in our emergency unit. This phenomenon, not observed with other beta-lactamics or even other penicillins, consisted of a continuous false positive result in the urinary detection of amphetamine and its metabolites that lasted up to 50 days after the antibiotic was administered. This finding not only seems to be specific to the benzathine salt, but also to the enzymoimmunoanalysis used to detect drug abuse.     

Persistence of penicillin G benzathine in pregnant group B streptococcus carriers

OBJECTIVE: To determine if streptococcicidal levels of penicillin G benzathine can be detected in maternal serum 4 weeks after treatment with 4.8 million units. METHODS: Thirty-seven pregnant women with positive group B streptococcus vaginal or urine cultures were each given 4.8 million units of penicillin G benzathine. Maternal blood samples were collected after injection and at delivery. Serum penicillin levels were measured by high-pressure liquid chromatography. Follow-up cultures were done when possible. RESULTS: None of the patients had serum penicillin levels below 0.20 microgram/mL 30 days after treatment. Cord blood levels were approximately 50% lower than maternal levels. In all but three subjects, cord blood levels exceeded 0.06 microgram/mL, the minimal inhibitory concentration for group B streptococcus. The three exceptions were patients who delivered more than 100 days after treatment. Group B streptococcus cultures were negative at the time of delivery in 72% of cases. None of the patients with positive cultures were moderately or heavily colonized. CONCLUSION: In pregnant women, penicillin G benzathine levels are high enough to inhibit the growth of group B streptococcus for more than 4 weeks after injection with 4.8 million units. Further studies are needed to evaluate whether this regimen can prevent neonatal colonization and invasive group B streptococcus disease.     

Episodic dermatolymphangioadenitis (DLA) in patients with lymphedema of the lower extremities before and after administration of benzathine penicillin: a preliminary study

Dermatolymphangioadenitis (DLA) is a common and serious complication of obstructive peripheral lymphedema. The clinical characteristics of acute DLA are local tenderness and erythema of the skin, sometimes red streaks along the distribution of the superficial lymphatics and enlarged inguinal lymph nodes. Systemic symptoms include malaise, fever and chills. In its subacute or latent form, only skin involvement is observed. Each episode of DLA is commonly followed by worsening of leg swelling. Numerous clinical studies suggest that administration of antibiotic drugs interrupt the acute episodes and prevent their recurrence. We investigated the clinical course of lymphedema with respect to the prevalence of DLA in patients receiving injections of long-acting penicillin (benzathine penicillin). Forty-five randomly selected patients with obstructive lymphedema of the lower limbs were included in an open clinical trial. The inclusion criteria was stage II-IV lymphedema of postsurgical, posttraumatic, and postdermatitis type with at least 3 previous episodes of DLA. Benzathine penicillin (PCN) was given after the last presenting episode of DLA in a dose of 1,200,000 u, intramuscularly at 3-week intervals, for at least one year. Each patient was reevaluated at 3-month intervals. They were instructed in early diagnosis of DLA and reported promptly to the responsible senior surgeon with prodrome symptoms of recurrent DLA. The duration of lymphedema before initiation of therapy was 7 months to 40 years and the frequency of DLA was 1-6 episodes per year. PCN administration lasted for at least one year but was extended in all patients because of the tendency for recurrence of DLA after cessation of PCN injections. In 26 of these patients, PCN administration extended to over 5 years and in 2 over 10 years. Recurrent episodes of DLA occurred in the PCN-treated group during one year follow-up in only 4 of the 45 patients (9%). The frequency episodes in 3 patients with recurrent DLA was 1-2/year; in one patient, no positive effect of PCN therapy was observed. There were no apparent side effects of long-term PCN therapy. These data, although evaluated without a placebo group, suggest that long-term PCN administration decreases the frequency of DLA attacks and furthermore provide justification for carrying out a double-blind randomly placebo-controlled clinical trial of the efficacy of prophylactic antibiotic drug treatment in forestalling DLA episodes.     

Detection of penicillin G and ampicillin as contaminants in tetracyclines and penicillamine

A method was developed to detect residual levels of ampicillin and penicillin G in various tetracyclines and penicillamine. Residues are detected by reversed-phase TLC followed by bioautography. The directness of the techniques makes this method a good means of detecting residual contaminants in drugs.     

Analysis of penicillin G in milk by liquid chromatography

A liquid chromatographic (LC) method that was previously developed for penicillin G residues in animal tissues has been adapted to milk and milk products. After protein precipitation with sodium tungstate, samples are applied to a C18 solid-phase extraction cartridge, from which penicillin is eluted, derivatized with 1,2,4-triazole-mercuric chloride solution, and analyzed by isocratic liquid chromatography (LC) on a C18 column with UV detection at 325 nm. Quantitation is done with reference to penicillin V as an internal standard. Penicillin G recoveries were determined to be > 70% on standards fortified at 3-60 ppb. Accuracy approached 100% using the penicillin V internal standard. The detection limit for penicillin G residues was 3 ppb in fluid milk. Samples may be confirmed by thermospray/LC at concentrations approaching the detection limit of the UV method.     

Immobilization of whole-cell penicillin G acylase by entrapping within polymethacrylamide beads

Escherichia coli ATCC 11105 containing the periplasmic penicillin G acylase was entrapped within a copolymer of methacrylamide and N,N'-methylenebisacrylamide. A solution of monomer that was made up from methacrylamide and N,N'-methylenebisacrylamide dissolved in buffer was mixed with lyophilized cells and ammonium persulfate. This suspension was then pumped drop by drop into in soybean oil supplemented with 0.06% (v/v) 3-(dimethylamino)-propionitril. During submerging in the oil phase, the droplets were hardened and induced to polymerize within the droplets. Particles with a volume ranging from 0.013-0.017 mL per bead containing a biomass concentration up to 38.0 g/L were prepared. The optimal condition for the deacylation of penicillin G to 6-aminopencillanic acid (6-APA) catalyzed by the immobilized whole-cell penicillin G acylase was found to be 45 degrees C and pH 8.0. Product inhibition of this enzyme by 6-APA could be eliminated by controlling pH value at 8 during the course of penicillin G hydrolysis using a pH-stat. Conversion determined by the pH-stat method were 0.3% higher than that by p-dimethylaminobenzaldehyde method. Cell concentration in the matrix was found to be an important factor influencing the maximum velocity and the specific activity retained in the matrix. A kinetic model, in which the mass transfer resistances as a result of external film mass transfer and pore diffusion were assumed to be negligible, could properly describe the hydrolysis of penicillin G by the cells entrapped within the polymethacylamide beads.     

Detection of milk antibiotic residues by use of screening tests and liquid chromatography after intramammary administration of amoxicillin or penicillin G in cows with clinical mastitis

OBJECTIVE: To compare results of 6 commercially available milk antimicrobial screening tests with results of liquid chromatography (LC) when testing milk samples from individual cows treated for mild clinical mastitis by intramammary (IMM) infusion with amoxicillin or penicillin G. ANIMALS: 6 cows with noninduced clinical mastitis: 3 treated by IMM infusion with amoxicillin and 3 treated by IMM infusion with penicillin G. PROCEDURE: Composite milk samples were collected before, during, and after treatment. Samples were assayed by use of the screening tests and their results and those of LC were compared. The LC results were assumed to represent the true result. RESULTS: Results of screening tests compared well with results of LC, with agreement of 94%. Positive screening test results for samples containing drug values below the established tolerance or safe level, as evaluated by LC, were obtained from 2 cows in which abnormal milk, as well as marked increases in composite milk somatic cell count, were observed. With the exception of 1 test in 1 cow, all screening tests had negative results at the end of the labeled milk-withholding time. CONCLUSIONS AND CLINICAL IMPLICATIONS: On the basis of results of the limited sample reported, the screening tests appeared to provide good agreement overall, compared with LC results, when testing milk of individual cows treated by IMM infusion with amoxicillin or penicillin G. Positive screening test results for milk samples containing amoxicillin or penicillin G at values below the established tolerance or safe level, as evaluated by LC, may occasionally be obtained.     

Lidocaine cardioplegia for prevention of reperfusion ventricular fibrillation

Lidocaine addition to crystalloid cardioplegic solution for prevention of reperfusion ventricular fibrillation after the release of the aortic cross-clamp was studied in 50 patients undergoing coronary artery bypass grafting and in 30 patients undergoing mitral or aortic valve replacement. Twenty-six of the patients undergoing coronary artery bypass grafting received lidocaine, 100 mg/L of cardioplegia, whereas a control group of 24 patients received cardioplegia without lidocaine. In the group undergoing valve replacement, 14 patients received lidocaine cardioplegia and 16 patients served as control. In the coronary artery bypass grafting group, lidocaine cardioplegia reduced significantly the incidence of reperfusion ventricular fibrillation from 100% to 42%. In the valve group, lidocaine cardioplegia also reduced significantly the incidence of reperfusion ventricular fibrillation from 93% to 42%. In both groups, lidocaine cardioplegia decreased the number of direct-current countershocks required to defibrillate the heart, with no significant increase in the incidence of high-grade atrioventricular block.     

Change in susceptibility of group B streptococci to penicillin G from 1968 through 1975

This report describes a study of 212 isolates of group B streptococci from sore throats over an 8-year period. A small but increasing percentage showed increased resistance to penicillin G when tested in an in vitro system.     

Motility of ram spermatozoa during storage in a chemically-defined diluent containing antioxidants

The effects of five antioxidants--Vitamin E (VE), butylated hydroxyanisole (BHA), n-propyl gallate (n-PG), deferoxamine mesylate (Desferal) and catalase (EC 1 . 11 . 1 . 6)--on the maintenance of motility of ram spermatozoa in a chemically-defined ram semen diluent (RSD-1) have been evaluated. VE, n-PG and Desferal inhibited spermatozoal motility. The relative inhibition (i.e., ratio of change in % motility over 24 h between the treatment group and the corresponding control) at equimolar concentrations (100 microM) of Desferal, VE and n-PG were 1.6, 1.8 and 3.6 respectively. BHA had no effect at 10 microM but at lower concentrations, gave a slight improvement in motility in freshly diluted spermatozoal samples and in those stored for 1 day at 15 degrees C. The addition of catalase to RSD-1 was also ineffective in improving the motility of spermatozoa. The lack of beneficial effects of the tested antioxidants suggests that RSD-1 itself may destroy reactive oxygen species and the antioxidant activity of RSD-1 components requires further study.     

Persistent hypocitrullinaemia as a marker for mtDNA NARP T 8993 G mutation?

Experimental equipment for in-vivo registrations of pull-out load vs displacement, applied torque vs angle of rotation, and lateral load vs lateral displacement has been developed. The set-up is designed for testing three implants inserted in a row and osseointegrated in, for instance, the proximal tibia of the beagle dog. The details of the set-up are described and considerations of the stress distributions are reported.     

Sphingosine-1-phosphate as a ligand for the G protein-coupled receptor EDG-1

The sphingolipid metabolite sphingosine-1-phosphate (SPP) has been implicated as a second messenger in cell proliferation and survival. However, many of its biological effects are due to binding to unidentified receptors on the cell surface. SPP activated the heterotrimeric guanine nucleotide binding protein (G protein)-coupled orphan receptor EDG-1, originally cloned as Endothelial Differentiation Gene-1. EDG-1 bound SPP with high affinity (dissociation constant = 8.1 nM) and high specificity. Overexpression of EDG-1 induced exaggerated cell-cell aggregation, enhanced expression of cadherins, and formation of well-developed adherens junctions in a manner dependent on SPP and the small guanine nucleotide binding protein Rho.     

Double-blind photoarray administration as a safeguard against investigator bias.

[Correction Notice: An erratum for this article was reported in Vol 85(2) of Journal of Applied Psychology (see record 2007-17253-001). On page 947, the graphs within Figure 1 were incorrectly labeled. The corrected figure appears in this erratum.] This experiment examined whether a photoarray administrator's knowledge of a suspect's identity increased false identification rates. Fifty participant–administrators (PAs) presented 50 participant–witnesses (PWs) two perpetrator-absent photoarrays following a live staged crime involving two perpetrators. For one photoarray per trial, the experimenter revealed the suspect's identity to the PA. Each PA presented the photoarrays sequentially or simultaneously in the presence or absence of an observer. When the observer was present, PA knowledge of the suspect's identity had a biasing effect in sequential photoarrays only. This pattern did not emerge when the observer was absent. The experimental manipulations did not affect PAs' and PWs' ratings of photoarray fairness or PWs' ratings of pressure to make an identification. These data suggest that only administrators who are blind to the suspect's identity should present sequential photoarrays. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

G542X as a probable Phoenician cystic fibrosis mutation

Only one prior study has examined social competence (SC) in drug addicted individuals. That study of cocaine-addicted individuals found gender differences in SC as well as differences based on the type of comorbid psychiatric diagnoses given. This study attempts to replicate findings from that cocaine study in a sample of opiate-addicted individuals and explores the relationship of SC to short-term treatment response. Gender differences in SC were examined in 28 women and 44 men attending a community methadone maintenance program. The question of differences in SC based on comorbid psychiatric diagnoses and treatment response were examined in a sample of 198 men attending a Veterans Administration methadone program. Women were found to have significantly lower SC than men. No significant differences in SC were revealed based on the presence of specific psychiatric diagnoses. SC was not related to short-term treatment response.     

Electromotive drug administration of lidocaine as an alternative anesthesia for transurethral surgery

PURPOSE: A multicenter study was undertaken to evaluate the safety, efficacy and cost of electromotive drug administration of intravesical lidocaine to produce bladder local anesthesia as an alternative to traditional methods of spinal or general anesthesia. MATERIALS AND METHODS: A total of 94 patients were enrolled in the study who had either a history of bladder tumor that required cold cup bladder biopsy with fulguration for possible recurrence as a comparison trial, a bladder tumor treated with transurethral resection/fulguration or benign prostatic hyperplasia/carcinoma treated with transurethral resection. Pain scores using a Verbal Rating Scale were recorded for each individual biopsy, fulguration and resection event. Data for direct and indirect costs were collected using a standardized form for each patient to capture the details of the procedure, including times, drugs and disposables for each patient. RESULTS: There was a significant reduction in pain for patients who received electromotive intravesical lidocaine compared to no anesthesia for biopsy (p<0.03). Similarly, electromotive intravesical lidocaine for bladder biopsy and transurethral bladder tumor resection/fulguration was associated with higher patient satisfaction compared to previous treatments (p<0.00002). In contrast, electromotive intravesical lidocaine was insufficient for 3 of 6 transurethral prostatic resections. The cost per patient was about $146 Cdn less with electromotive intravesical lidocaine than with conventional general/spinal anesthesia. CONCLUSIONS: Electromotive intravesical lidocaine may be a safe, effective and affordable form of anesthesia for the ambulatory care of patients requiring transurethral bladder biopsy, resection or fulguration with a potential for cost savings.