The increased bactericidal activity of a fatty acid-modified synthetic antimicrobial peptide of human cathepsin G correlates with its enhanced capacity to interact with model membranes

The bactericidal potency of a synthetic peptide (CG 117-136) of human lysosomal cathepsin G (cat G) can be substantially increased by covalent attachment to its N- or C-termini, of saturated, linear fatty acids (FAs), namely those with C-8, C-10 and C-12 hydrocarbon chains. In order to understand better the mechanism by which FA moieties increase the bactericidal activity of CG 117-136, the interaction of N-terminally FA-modified peptides with artificial membranes was studied. First, the content of secondary structure motifs in the modified and unmodified peptides was determined by circular dichroism (CD). A marked increase in the propensity of FA-modified CG 117-136 to form an alpha-helix structure was observed for the C-8, C-10 and C-12 derivatives compared with unmodified/short-chain and long-chain (C-14, C-16, C-18) derivatives. These effects were observed both in the presence of large unilamellar liposomes or in trifuluoroethanol, a membrane-stimulating agent. Second, the capacity of peptides to insert into large unilamellar liposomes as a function of FA length was determined by their ability to release a trapped fluorescent dye. FA derivatives with the highest alpha-helical content were found to be the most effective in releasing a fluorescent dye, compared with an unmodified peptide and/or derivatives having a low alpha-helical content. The ability of the peptides to attain alpha-helical structure in the membrane-like environment and the ability to disrupt the liposomal membrane, therefore correlate remarkably well with their increased ability to kill bacteria. A plausible explanation for improved bactericidal action of the modified peptide is that the FA moiety facilitates formation of the peptide with an alpha-helical structure formation in membranes, which is essential for disrupting the integrity of the bacterial cytoplasmic membrane.     

Inflammatory arthritis in the elderly

The three most common inflammatory arthritic conditions affecting the elderly are reviewed, along with current information about the various treatments.     

Altered receptor trafficking in Huntingtin Interacting Protein 1-transformed cells

The clathrin-associated protein, Huntingtin Interacting Protein 1 (HIP1), is overexpressed in multiple human epithelial tumors. Here, we report that HIP1 is a novel oncoprotein that transforms cells. HIP1-transformed cells, in contrast to RasV12-transformed cells, have dysregulation of multiple receptors involved in clathrin trafficking. Examples include upregulation of the epidermal growth factor receptor (EGFR) and the transferrin receptor. Furthermore, accumulation of transferrin and EGF in the HIP1-transformed cells was increased, and breast tumors that had EGFR expressed also had HIP1 upregulated. Thus, HIP1 overexpression promotes tumor formation and is associated with a general alteration in receptor trafficking. HIP1 is the first endocytic protein to be directly implicated in tumor formation.     

Sequence analysis of dru regions from methicillin-resistant Staphylococcus aureus and coagulase-negative staphylococcal isolates

Methicillin-resistance in staphylococci results from expression of mecA, which occurs in a larger region of DNA (the mec region) lacking counterpart in susceptible cells. The mec region harbors in addition a highly polymorphic element, the dru (direct repeat unit) segment, which in an early S. aureus strain, BB270, was found to contain 10 imperfect 40 base-pair repeats. We have explored the utility of direct sequencing of dru segments for discriminating among strains of methicillin-resistant S. aureus (MRSA) and coagulase-negative staphylococci (MRCNS). We sequenced dru segments of 24 clinical isolates of MRSA, and 15 of MRCNS, and reexamined strain BB270. Six S. aureus and 2 S. epidermidis isolates were found to have deletions which removed all drus. The other strains were found to have multiple contiguous dru repeats of precisely 40 bp. Analysis of these strains plus dru segment sequence from 4 recent reports yielded 18 unique dru segment sequences (designated "dru types") differing in numbers of repeats and/or sequences of particular repeats. Dru typing was more discriminating than sequencing of non-mec region genes, including a repeat-containing segment (spa Xr) of the S. aureus protein A gene. Yet dru type was sufficiently stable to register epidemiological clusters. Dru sequencing is a useful tool for tracking methicillin-resistant lineages of S. aureus and CNS.     

Allograft dermal implant (AlloDerm) in a previously irradiated field

OBJECTIVE: To evaluate the integration of AlloDerm (LifeCell Corp., The Woodlands, TX) in a field exposed to external-beam radiation (EBR) by analyzing graft thickness, fibroblast recellularization, and neovascularization. STUDY DESIGN: Randomized control. METHODS: Thirty-six male Sprague-Dawley rats (n = 36) were randomly assigned to four groups. One hind leg of each rat was exposed to 20 Gy of EBR; the other limb served as the nonirradiated control. Two weeks after irradiation, AlloDerm was implanted into both hind legs. Grafts were harvested at 3, 4, 6, and 14 weeks after implantation and underwent histological analyses. RESULTS: There was no statistically significant difference in graft thickness, fibroblast count, or neovascularization between the grafts placed in the irradiated bed and the controls (n = 33, P = .332, P = .336, and P = .057, respectively). However, at week 3, fibroblast counts in the graft placed in the field exposed to EBR were significantly lower than those of controls (P = .019), although at week 14 the counts in the experimental limb were higher than those of the controls (P = .002). Graft thickness (P = .001) and fibroblast count (P < .004) were lower at week 14 than at earlier time periods for both the experimental and control grafts. CONCLUSIONS: In the rat model, graft thickness and neovascularization of the AlloDerm dermal implant do not appear to be adversely affected by a field that has received EBR. Fibroblast ingrowth may be hindered in the early postimplantation period but appears to normalize in the long term. Furthermore, overall graft thickness and fibroblast counts decrease over time, regardless of irradiation status.     

Immunization of Early Adolescent Females with Human Papillomavirus Type 16 and 18 L1 Virus-Like Particle Vaccine Containing AS04 Adjuvant

PurposeIn female individuals 15–25-years of age, the AS04-containing human papillomavirus (HPV)–16/18 vaccine is highly immunogenic and provides up to 100% protection against HPV-16/18 persistent infection and associated cervical lesions up to 4.5 years. Optimal cervical cancer prevention will require prophylactic vaccination against oncogenic HPV 16 and 18 before the onset of sexual activity in early adolescent girls. To establish the feasibility of vaccination in girls 10–14 years of age, we compared the immunogenicity and safety in early adolescent female individuals to those 15–25 years in whom vaccine efficacy has been demonstrated.MethodsWe enrolled 773 female participants aged 10–14 years and 15–25 years to receive the HPV-16/18 L1 VLP AS04 vaccine, which was administered at months 0, 1, and 6. Serum samples were collected at months 0 and 7; antibodies to HPV 16 and 18 VLPs were measured by enzyme-linked immunosorbent assay. Vaccine safety was assessed at 7 or 30 days after each dose; serious adverse events were recorded during the entire study period.ResultsBoth age groups achieved 100% seroconversion for HPV 16 and 18. Participants in the group aged 10–14 years were not only noninferior to those 15–25 years in terms of HPV 16 and 18 seroconversion rates but also had approximately twice as high geometric mean titers. The vaccine was generally safe and well tolerated.ConclusionsThese findings suggest that HPV vaccination during early adolescence is generally safe, well tolerated, and highly immunogenic. The observed higher antibody titers in the group 10–14 years of age are likely to result in longer antibody persistence. Overall, these data support the implementation of prophylactic HPV vaccination in this age group.     

Long-term use of Levetiracetam in patients with severe childhood-onset epilepsy

OBJECTIVE: To assess the efficacy and tolerability of Levetiracetam (LEV) in children and adolescents with refractory epilepsy with a special interest in the long-term retention rate. METHOD: One hundred and twenty-nine patients (83 male, 46 female; mean age 10.6 years/range: 6 months-39 years 9 months) were included in a prospective, open-label, add-on trial of LEV for up to 3 years. All patients had severe forms of epilepsy starting before the age of 10 often accompanied by mental retardation. Primary outcome measures were changes in seizure frequency after 6 months on the medication with LEV, with initial responders (>50% seizure reduction). Further objective was the retention rate of LEV therapy after 3 years defined as percentage of patients still taking LEV. RESULTS: Thirty-five patients (27.1%) were initial responders of which 5 became seizure free. The average maximum LEV dosage was 39.8 mg/kg/day (range: 6-70 mg/kg/day) with no difference responders vs. no responders. The retention rate for responders after 3 years was 22.5%. The rate of side effects was 39.8% in all patients, with the most frequent side effects being fatigue (12.5%), aggressiveness (7.8%) and gastrointestinal disorders (13.3%). CONCLUSIONS: Our study in patients with refractory epilepsy suggests that our initial responders were very likely to be still taking LEV after 3 years. We therefore consider treatment with LEV in this special group of patients with refractory epilepsy a promising therapeutic option, because of its favourable tolerance profile, the option of fast titration and the absence of drug interactions.     

Intra-amniotic urea and prostaglandin F2alpha for midtrimester abortion: clinical and laboratory evaluation.

The clinical management of the elective midtrimester abortion continues to be unsatisfactory as judged by either national mortality or morbidity rates. This report documents the results of a randomized series of 19 midtrimester abortions induced by either intra-amniotic hyperosmolar urea and 5 mg. of prostaglandin F2alpha (PGF2alpha) or intra-amniotic hyperosmolar urea alone. Pertinent clinical characteristics and biochemical determinations were compared between these two groups. A series of 150 patients were then treated with urea and 5 mg. of PGF2alpha. The clinical results of this series of patients are presented and compared with a previous group who had urea and 10 mg. of PGF2alpha. These studies demonstrate that 5 mg. of PGF2alpha with 80 Gm. of urea achieves injection-abortion intervals that are less than 24 hours.     

13, 14-dihydro-15-keto-prostaglandin F2alpha concentrations in human plasma and amniotic fluid.

An antiserum to 13,14-dihydro-15-keto-prostaglandin F2alpha (PGF2alphaM) was prepared and a radioimmunoassay evaluated in various reproductive states. PGF2alphaM plasma concentration was 63.6 +/- 10.3 pg/ml (mean +/- SEM) in cycling women. The concentration fluctuated throughout the menstrual cycle and pregnancy, but no discernible patterns were noted. PGF2alphaM concentrations were elevated at the time of urea + oxytocin induced abortion (238 +/- 54 pg/ml) and during late stages of normal labor (352 +/- 107 pg/ml) but were not elevated during labor prior to 7 cm dilatation. Following intra-amniotic instillation of 5 mg of PGF2alpha tromethamine into the amniotic sac, PGF2alphaM concentration increased in the amniotic fluid. In the plasma of these patients there was an eighteenfold rise in plasma PGF2alphaM concentration compared to a 3.5-fold rise in PGF2alpha at 1 hour, suggesting changes in PGF2alphaM may be more easily detected than the parent compound. While PGF2alphaM may be a useful index of PGF2alpha production, it appears that PGF2alphaM is of little value in predicting the occurrence of uterine contraction.     

Cardiogenic shock in myocardial infarction-results of in-hospital follow-up

The purpose of this study was to present the outcomes of treatment of cardiogenic shock (CS) complicating acute myocardial infarction (AMI) among patients hospitalized from 1999 through 2006. The study enrolled 1003 patients. Group 1 comprised 87 patients presenting with AMI complicated with CS, whereas Group 2 comprised 916 patients presenting with AMI without CS symptoms. Determination of invasive treatment was according to standard guidelines. The endpoint comprised death, stroke, and reocclusion/reinfarction. Follow-up was confined to the intra-hospital period. CS was observed more frequently in cases of ST-elevation MI (STEMI) and right ventricular MI. The transportation and door-to-needle time were shorter in Group 1. CS patients were characterized by a more severe coronary artery disease, higher maximal creatinine kinase levels, lower global ejection fractions, and increased incidence of atrioventricular conduction disorders. The efficacy of percutaneous coronary intervention (PCI) was 82.26% in Group 1 and 95.03% in Group 2. Death occurred in 33.3% of CS patients and in 3.6% of AMI patients (p<0.0001). Our study proved that in a short-term follow-up, PCI is a procedure of high efficacy in CS patients. The short-term follow-up precluded a conclusion of statistically significant benefits from the shortening of the transportation and door-to-needle time.