Photoinduced electron transfer in porphyrin-naphthyl pairs covalently and randomly bound to α-helical poly(L-lysine)

The photophysics of protoporphyrin-naphthyl (P-N) pairs covalently and randomly bound to the ε-amino groups of the side-chains of poly(L -lysine) (PL) were investigated by steady-state and time-resolved fluorescence measurements. The results indicate that quenching of excited naphthalene (λ_ex = 280 nm) chiefly occurs by interconversion to the triplet state when the polymeric matrix is in random coil (pH ≈ 7) and by intramolecular electron transfer from ground-state porphyrin, P → ¹N^*, when the polypeptide is in α-helical conformation (pH ≈ 11), the specific rate constant of the electron transfer being 3,1 · 10⁷ s^?1 (25°C). PNPL exhibits very little exciplex fluorescence, whatever the pH, suggesting both a reduced internal Brownian motion of the chromophores, owing to the amide bond in the substituted side-chains, and a relatively large average interprobe separation distance. This agrees with polarized fluorescence data and with the results of a conformational statistics analysis on the fully ordered PNPL, indicating that the average interchromophoric distance for which the electron transfer has the highest probability to occur is around 12 Å. The computational results allowed us to reproduce the experimental fluorescence decay curves and estimate the parameters governing the electron transfer process. Implications of these findings on the relaxation time of the heli-xcoil transition in PNPL are briefly discussed.     

Isolation and identification of pathogenic Acanthamoeba strains in Tenerife, Canary Islands, Spain from water sources

A comprehensive survey to document the presence of free-living amoebae of the genus Acanthamoeba was conducted in tap water and sea water sources related to human environments in Tenerife, Canary Islands, Spain. Acanthamoeba identification was based on the morphology of cyst and trophozoite forms and PCR amplification with a genus-specific primer pair. The pathogenic potential of Acanthamoeba isolates was characterized by temperature and osmotolerance assays and PCR reactions with two primer pairs related to Acanthamoeba pathogenesis. The results demonstrate the presence of potentially pathogenic strains in both sources. Thus, some of the amoebae in these aquatic habitats can act as opportunistic pathogens, could play a role in the diseases of aquatic organisms, and may present a risk to human health.     

Inhibition of 3-Hydroxy-3-Methylglutaryl–Coenzyme A Reductase and Application of Statins as a Novel Effective Therapeutic Approach against Acanthamoeba Infections

Acanthamoeba is an opportunistic pathogen in humans, whose infections most commonly manifest as Acanthamoeba keratitis or, more rarely, granulomatous amoebic encephalitis. Although there are many therapeutic options for the treatment of Acanthamoeba, they are generally lengthy and/or have limited efficacy. Therefore, there is a requirement for the identification, validation, and development of novel therapeutic targets against these pathogens. Recently, RNA interference (RNAi) has been widely used for these validation purposes and has proven to be a powerful tool for Acanthamoeba therapeutics. Ergosterol is one of the major sterols in the membrane of Acanthamoeba. 3-Hydroxy-3-methylglutaryl–coenzyme A (HMG-CoA) reductase is an enzyme that catalyzes the conversion of HMG-CoA to mevalonate, one of the precursors for the production of cholesterol in humans and ergosterol in plants, fungi, and protozoa. Statins are compounds which inhibit this enzyme and so are promising as chemotherapeutics. In order to validate whether this enzyme could be an interesting therapeutic target in Acanthamoeba, small interfering RNAs (siRNAs) against HMG-CoA were developed and used to evaluate the effects induced by the inhibition of Acanthamoeba HMG-CoA. It was found that HMG-CoA is a potential drug target in these pathogenic free-living amoebae, and various statins were evaluated in vitro against three clinical strains of Acanthamoeba by using a colorimetric assay, showing important activities against the tested strains. We conclude that the targeting of HMG-CoA and Acanthamoeba treatment using statins is a novel powerful treatment option against Acanthamoeba species in human disease.     

Case for diagnosis

Idiopathic Atrophoderma of Pasini and Pierini (IAPP) is a rare, exclusively cutaneous disease. It is more frequent in females, with incidence peak in the second and third decades of life. The etiopathogenesis remains unknown. IAPP most commonly affects the back, abdomen and proximal regions of the limbs. Lesions may be rounded, oval or circular; single or multiple. The evolution is variable and the course is initially progressive. Collagen changes such as atrophy, thinning, condensation and sclerosis may be observed in the papillary dermis. This paper describes a case of Idiopathic Atrophoderma of Pasini and Pierini with histopathologic findings.     

Tantalum Cones in Revision Total Knee Arthroplasty. A Promising Short-Term Result With 29 Cones in 21 Patients

Twenty-nine porous tantalum metaphyseal cones were implanted in 21 patients (14 women and 7 men) during revision TKA. The average age at the time of the procedure was 73.3 years. Sixteen revisions were considered aseptic and 5 were reimplantations after sepsis. Eight patients had stemmed revision implants and thirteen primary designs. According to the Anderson Orthopaedic Research Institute bone defect classification, femoral defects were rated as F3 in 14 knees and F2B in 3 knees. Tibial defects were rated as T2A in 3 cases, T2B in 3 cases and T3 in 5 cases. A femoral cone was inserted in 10 patients, a double cone (femur and tibia) in 8, and a single tibial cone in 3. A rotating hinge knee prosthesis (RHK, Zimmer) was inserted in 10 patients and a constrained condylar prosthesis (LCCK, Zimmer) in 11 patients. The diaphysis was cemented in 9 cases and, in 11 cases, just the metaphysis. At an average follow up of 36 months only one reconstruction was removed due to persistent infection. All metaphyseal cones showed evidence of stable osseointegration. According to the Knee Society Score the results were rated as excellent in 12 cases, good in 5 cases, fair in 3 and poor in 1 case. In the short term, porous tantalum metaphyseal cones provided structural support for large femoral and tibial defects. They also provided the environment for bone graft osseointegration, repair of femoral fractures and effective interdigitation of cement mantle into the trabecular metal cone.     

Epidemiology, clinical characteristics, outcome, morbidity and mortality in acromegaly based on the Spanish Acromegaly Registry (Registro Espanol de Acromegalia, REA)

OBJECTIVE: To undertake a multicentre epidemiological study reflecting acromegaly in Spain. DESIGN: Voluntary reporting of data on patients with acromegaly to an online database, by the managing physician. METHODS: Data on demographics, diagnosis, estimated date of initial symptoms and diagnosis, pituitary imaging, visual fields, GH and IGF-I concentrations (requested locally), medical, radiotherapy and neurosurgical treatments, morbidity and mortality were collected. RESULTS: Data were included for 1219 patients (60.8% women) with a mean age at diagnosis of 45 years (s.d. 14 years). Reporting was maximal in 1997 (2.1 cases per million inhabitants (c.p.m.) per year); prevalence was globally 36 c.p.m., but varied between 15.7 and 75.8 c.p.m. in different regions. Of 1196 pituitary tumours, most were macroadenomas (73%); 81% of these patients underwent surgery, 45% received radiotherapy and 65% were given medical treatment (somatostatin analogues in 68.3% and dopamine agonists in 31.4%). Cures (GH values (basal or after an oral glucose tolerance test) <2 ng/ml, normal IGF-I, or both) were observed in 40.3% after surgery and 28.2% after radiotherapy. Hypertension (39.1%), diabetes mellitus (37.6%), hypopituitarism (25.7%), goitre (22.4%), carpal tunnel syndrome (18.7%) and sleep apnoea (13.2%) were reported as most frequent morbidities; 6.8% of the patients had cancer (breast in 3.1% of the women and colon in 1.2% of the cohort). Fifty-six patients died at a mean age of 60 years (s.d. 14 years), most commonly of a cardiovascular cause (39.4%); mortality was greater in patients given radiotherapy (hazard ratio 2.29; 95% confidence interval 1.03 to 5.08; P=0.026), and in those in whom GH and IGF-I concentrations were never normal (P<0.001). CONCLUSIONS: This acromegaly registry offers a realistic overview of the epidemiological characteristics, treatment outcome and morbidity of acromegaly in Spain. As active disease and treatment with radiotherapy are associated with an increase in mortality, efforts to control the disease early are desirable.     

Bacteriology of the anal wound after open hemorrhoidectomy

The purpose of this study is to analyze the size of the bacterial colonies in anal wounds after open hemorrhoidectomy. Twenty patients were studied during predetermined postoperative time periods. Material was collected from the surface and from within the tissue of each patient's three open wounds, intraoperatively, on the 6th, 13th and 20th postoperative days for bacteriologic examination in aerobic, microaerophilic, and anaerobic media. The bacterium most commonly identified was Escherichia coli,followed by Staphylococcus aureus and Staphylococcus epidermidis. Pseudomonas aeruginosa, Enterococcus faecalis, Klebsiella pneumoniae, Proteus vulgaris,and Proteus mirabilis were also identified. Critical indexes of colonization were present since the intraoperative stage (>10 ⁵ bacteria/g of tissue and >10 ⁶ bacteria/ml); obligate anaerobic bacteria were not identified; neither the species nor the number of bacteria, even when critical indexes were present, prevented proper healing. The same bacteria were not necessarily present on the surface and in the tissue; the bacterial load observed among the three wounds (left lateral, right posterior, and right anterior), was the same.Presented at the Postgraduate Course, Surgical Technique and Experimental Surgery, offered by the Escola Paulista de Medicina (Paulista Medical School) and the Department of Biomedical Sciences of the University of Taubaté, São Paulo, Brazil.     

Statins and Voriconazole Induce Programmed Cell Death in Acanthamoeba castellanii

Members of the genus Acanthamoeba are facultative pathogens of humans, causing a sight-threatening keratitis and a life-threatening encephalitis. In order to treat those infections properly, it is necessary to target the treatment not only to the trophozoite but also to the cyst. Furthermore, it may be advantageous to avoid parasite killing by necrosis, which may induce local inflammation. We must also avoid toxicity of host tissue. Many drugs which target eukaryotes are known to induce programmed cell death (PCD), but this process is poorly characterized in Acanthamoeba. Here, we study the processes of programmed cell death in Acanthamoeba, induced by several drugs, such as statins and voriconazole. We tested atorvastatin, fluvastatin, simvastatin, and voriconazole at the 50% inhibitory concentrations (IC₅₀s) and IC₉₀s that we have previously established. In order to evaluate this phenomenon, we investigated the DNA fragmentation, one of the main characteristics of PCD, with quantitative and qualitative techniques. Also, the changes related to phosphatidylserine exposure on the external cell membrane and cell permeability were studied. Finally, because caspases are key to PCD pathways, caspase activity was evaluated in Acanthamoeba. All the drugs assayed in this study induced PCD in Acanthamoeba. To the best of our knowledge, this is the first study where PCD induced by drugs is described quantitatively and qualitatively in Acanthamoeba.     

Voriconazole as a first-line treatment against potentially pathogenic Acanthamoeba strains from Peru

Pathogenic strains of Acanthamoeba genus are the causative agents of fatal granulomatous amoebic encephalitis and a serious sight-threatening infection of the eye known as Acanthamoeba keratitis. In a previous study, Acanthamoeba strains were isolated from nasal swabs collected from healthy individuals in Peru. In the present study, the pathogenic potential of the isolated strains was established based on temperature and osmotolerance assays as well as the secretion rate of extracellular proteases. Based on these experiments, four strains that showed the highest pathogenic potential were selected for sensitivity assays against two molecules (voriconazole and chlorhexidine) which are currently used for the treatment of Acanthamoeba infections. After performing sensitivity and activity assays, it was found that both drugs were active against the tested strains. However, voriconazole showed higher activity against the studied strains compared to chlorhexidine. Therefore, voriconazole should be established as a first-line treatment against Acanthamoeba infections at least in the studied region of Peru.     

Weight-Related Quality of Life in Spanish Obese Subjects Suitable for Bariatric Surgery is Lower Than in Their North American Counterparts: a Case–Control Study

Background

Obesity impairs quality of life, but the perception of the impairment could be different from one country to another. The purpose was to compare weight-related quality of life (QOL) between cohorts from Spain and North America.

Methods

A cross-sectional case–control study was performed between two populations. Four hundred Spanish and 400 North American obese subjects suitable for bariatric surgery closely matched for race, gender, age, and body mass index (BMI) were included. Two non-obese control groups matched for gender, age, and BMI from each population were also evaluated (n?=?400 in each group). The participants completed the Impact of Weight on Quality of Life—Lite (IWQOL—Lite) questionnaire, a measure of weight-related QOL.

Results

Spanish morbidly obese patients showed poorer QOL than their North American counterparts in physical function, sexual life, work, and total score. By contrast, Spanish non-obese control subjects reported better QOL in all domains than their North American counterparts. Women, both in Spain and North America, reported reduced QOL compared to men on the domain of self-esteem. In addition, North American women reported reduced QOL on the sexual life domain compared to men. BMI correlated negatively with all domains of QOL except for self-esteem in both national groups.

Conclusions

Spanish obese subjects suitable for bariatric surgery report poorer weight-related quality of life than their North American counterparts, and obese women, regardless of nationality, perceive a reduced quality of life compared to men.