Brucella species-induced brucellosis: Antimicrobial effects, potential resistance and toxicity of silver and gold nanosized particles.

Brucellosis is an endemic zoonotic disease caused by Brucella species, which are intramacrophage pathogens that make treating this disease challenging. The negative effects of the treatment regime have prompted the development of new antimicrobials against brucellosis. A new treatment modality for antibiotic-resistant microorganisms is the use of nanoparticles (NPs). In this study, we examined the antibacterial activities of silver and gold NPs (SNPs and GNPs, respectively), the resistance developed by Brucella melitensis (B. melitensis) and Brucella abortus (B. abortus) strains and the toxicity of both of these NPs in experimental rats. To test the bactericidal effects of the SNPs and GNPs, we used 22 multidrug-resistant Brucella isolates (10 B. melitensis and 12 B. abortus). The minimal inhibitory concentrations (MICs) of both types of NPs were determined utilizing the microdilution technique. To test the stability of resistance, 7 B. melitensis and 6 B. abortus isolates were passaged ten times in culture with subinhibitory concentrations of NPs and another ten times without NPs. Histopathological analysis was completed after rats were given 0.25, 0.5, 1, and 2 mg/kg NPs orally for 28 consecutive days. The MIC values (µg/ml) of the 10-nm SNPs and 20-nm GNPs against B. melitensis were 22.43 ± 2.32 and 13.56 ± 1.22, while these values were 18.77 ± 1.33 and 12.45 ± 1.59 for B. abortus, respectively. After extensive in vitro exposure, most strains showed no resistance to the 10-nm SNPs or 20-nm GNPs. The NPs and antibiotics did not cross-react in any of the evolved Brucella strains. SNPs and GNPs at doses below 2 mg/kg were not harmful to rat tissue according to organ histopathological examinations. However, a greater dose of NPs (2 mg/kg) harmed all of the tissues studied. The bactericidal properties of NPs are demonstrated in this work. Brucella strains develop similar resistance to SNPs and GNPs, and at low dosages, neither SNPs nor GNPs were hazardous to rats.

Jacques Forestier: Forgotten Contributions of a Rheumatologist to Spine Surgery.

Jacques Forestier (1890-1978) was a well-known rheumatologist and radiologist whose innovations have revolutionized spinal neurosurgery and rheumatology. He was well known as "Doctor Lipiodol" for his accidental discovery of spinal myelography, which he later extrapolated for use in many body cavities and their pathologies. He was the first to describe "senile ankylosing hyperostosis of the spine," which was later renamed "diffuse idiopathic skeletal hyperostosis." Furthermore, he is credited with the first use of gold salts as a disease-modifying therapy for rheumatoid arthritis. We have presented a historical vignette to chronicle the life of Jacques Forestier and his contributions to the field of spinal neurosurgery.

Gold Nanoparticles in Glioma Theranostics.

Despite many endeavors to treat malignant gliomas in the last decades, the median survival of patients has not significantly improved. The infiltrative nature of high-grade gliomas and the impermeability of the blood-brain barrier to the most therapeutic agents remain major hurdles, impeding an efficacious treatment. Theranostic platforms bridging diagnosis and therapeutic modalities aim to surmount the current limitations in diagnosis and therapy of glioma. Gold nanoparticles (AuNPs) due to their biocompatibility and tunable optical properties have widely been utilized for an assortment of theranostic purposes. In this Review, applications of AuNPs as imaging probes, drug/gene delivery systems, radiosensitizers, photothermal transducers, and multimodal theranostic agents in malignant gliomas are discussed. This Review also aims to provide a perspective on cancer theranostic applications of AuNPs in future clinical trials.

Perinatal use and discontinuation of disease-modifying anti-rheumatic drugs and biologics in women with rheumatoid arthritis: a cohort study.

OBJECTIVES: To characterize the utilization and discontinuation of medications before, during and after pregnancy among women with RA. METHODS: We used population-based administrative data to identify women with RA who had a singleton pregnancy ending in delivery between 1 January 2002 and 31 December 2012. We assessed the utilization of RA medications, namely, conventional synthetic DMARDs, biologics, glucocorticosteroids and NSAIDs, across six windows spanning 24 and 12 months before the start of pregnancy, each trimester of pregnancy and 12 months post-pregnancy. We defined medication discontinuation as no prescription in a given window following a prescription in the preceding window and evaluated predictors using logistic regression models, calculating adjusted odds ratios (ORs) and 95% CIs. RESULTS: We studied 1730 pregnancies in 1301 women with RA (mean age at delivery 31.4 ± 5.4 years). We observed substantial medication discontinuation, particularly in the first trimester, with discontinuation of antimalarials in 57.3% of patients, azathioprine 59.1%, sulfasalazine 69.5% and biologics 50.8%. Factors inversely associated with discontinuation of antimalarials in the first trimester were maternal age [OR 0.90 (95% CI 0.86, 0.95)] and number of rheumatology visits [OR 0.86 (95% CI 0.75, 0.97)] and for biologics, prior adverse birth outcome [OR 0.22 (95% CI 0.05, 0.95)]. CONCLUSION: Our population-based study shows frequent discontinuation of medications for RA, particularly in the first trimester. Findings indicate a need to educate women with RA who are planning pregnancy on the benefits and risks of medications during pregnancy.

Enhancement of linear energy transfer in gold nanoparticles mediated radiation therapy.

OBJECTIVE: The metric dose enhancement ratio (DER) has been widely used to assess the enhancing capability of gold nanoparticles (GNPs). However, there is a large disparity between the observed radiobiological outcome and DER values. A new metric, linear energy transfer enhancement ratio (LETER), is introduced to bridge the gap between theoretical predictions and the experimentally measured sensitization. METHODS: The radiation transport code SCEPTRE is used to examine the efficacy of the proposed new metric. Different clusters of GNPs irradiated with x-ray photons generated at 120 kVp and therapeutic 6 MV photon beams are investigated. For each pattern, two GNPs sizes are examined 50 and 100 nm. RESULTS: An enhancement in the linear energy transfer has been observed for both energies. In the case of 120 kVp, LETER is substantially lower than DER; moreover, it decreases with increasing GNP size. On the other hand, the results of 6 MV show that LETER is relatively higher than DER, and it increases with the size of GNP. For the studied energies, LETER is in good agreement with the sensitization reported in the literature. CONCLUSION: The results indicate the merit of LETER as a better indicator of the radiobiological outcome of GNP aided radiotherapy.

[Lichenoid drug reactions]. / Lichenoide Arzneimittelreaktionen.

Lichenoid drug reactions are rare compared to typical morbilliform drug exanthema or urticaria. They are associated with specific drugs or drug families like gold, antimalarial drugs, ß­blockers and angiotensin-converting-enzyme inhibitors. Recent observations included associations with novel drugs such as biologics (e. g. tumour necrosis factor antagonists) and immune checkpoint inhibitors (anti-programme cell death protein 1 antibodies). Lichenoid drug reactions most often resemble lichen planus mainly in areas of ultraviolet-light exposed skin, but also mucosal lichen planus and even bullous lesions may occur.

Light therapies for acne: abridged Cochrane systematic review including GRADE assessments.

We undertook a Cochrane review of randomized controlled trials (RCTs) evaluating the effects of light-based interventions for acne vulgaris. We searched the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, LILACS, ISI Web of Science and grey literature sources (September 2015). We used the Grading of Recommendations Assessment, Development and Evaluation Working Group approach to assess the quality of evidence (QoE). We included 71 RCTs (4211 participants, median sample size 31). Results from a single study (n = 266, low QoE) showed little or no difference in effectiveness on participants' assessment of improvement between 20% aminolaevulinic acid (ALA) photodynamic therapy (PDT), activated by blue light, vs. vehicle plus blue light, whereas another study (n = 180) comparing ALA-PDT (red light) concentrations showed that 20% ALA-PDT was no more effective than 15% ALA-PDT but better than 10% and 5% ALA-PDT. Pooled data from three studies (n = 360, moderate QoE) showed that methyl aminolaevulinate PDT, activated by red light, had a similar effect on changes in lesion counts vs. placebo cream with red light. Several studies compared yellow light with placebo or no treatment, infrared light with no treatment, gold microparticle suspension with vehicle and clindamycin/benzoyl peroxide (C/BPO) combined with pulsed dye laser with C/BPO alone. None of these showed any clinically significant effects. Most studies reported adverse effects, but inadequately, with scarring reported as absent, and blistering only in studies on intense pulsed light, infrared light and PDT (very low QoE). Carefully planned studies, using standardized outcome measures and common acne treatments as comparators, are needed.

Hilos de oro subcutáneos en una paciente con cervicalgia / Subcutaneous gold threads in a patient with neck pain

No disponible

Theranostic Gold Nanomicelles made from Biocompatible Comb-like Polymers for Thermochemotherapy and Multifunctional Imaging with Rapid Clearance.

A new generation of photothermal theranostic agents based on assembling 6 nm gold nanoparticles (AuNPs) is developed by using a novel comb-like amphipathic polymer as the template. The small AuNPs are assembled into DOX@gold nanomicelles, which show strong absorbance in the near-infrared region, for multimodal bioimaging and highly effective in vivo chemotherapy and photothermal therapy.

Cancer targeting with biomolecules: a comparative study of photodynamic therapy efficacy using antibody or lectin conjugated phthalocyanine-PEG gold nanoparticles.

The functionalisation of therapeutic nanoparticle constructs with cancer-specific biomolecules can enable selective tumour accumulation and targeted treatment. Water soluble gold nanoparticles (ca. 4 nm) stabilised by a mixed monolayer of a hydrophobic zinc phthalocyanine photosensitiser (C11Pc) and hydrophilic polyethylene glycol (PEG) have been prepared. The C11Pc-PEG gold nanoparticle constructs were further functionalised with jacalin, a lectin specific for the cancer-associated Thomsen-Friedenreich (T) carbohydrate antigen, or with monoclonal antibodies specific for the human epidermal growth factor receptor-2 (HER-2). The two biofunctionalised nanoparticle conjugates produced similar levels of singlet oxygen upon irradiation at 633 nm. Importantly, both nanoparticle conjugates demonstrated extensive, yet comparable, phototoxicity in HT-29 colorectal adenocarcinoma cells (80-90%) and in SK-BR-3 breast adenocarcinoma cells (>99%). Non-conjugated C11Pc-PEG gold nanoparticles were only minimally phototoxic. Lysosomal colocalisation studies performed with the HT-29 colon cancer cells and the SK-BR-3 breast cancer cells revealed that both nanoparticle conjugates were partially localised within acidic organelles, which is typical of receptor-mediated endocytosis. The similarity of the targeted PDT efficacy of the two biofunctionalised C11Pc-PEG gold nanoparticles is discussed with respect to targeting ligand binding affinity and cell surface antigen density as key determinants of targeting efficiency. This study highlights how targeting small cell-surface molecules, such as the T antigen, can mediate a selective photodynamic treatment response which is similar to that achieved when targeting overexpressed protein receptors, such as HER-2. The high prevalence of the T antigen present on the cellular surface of primary tumours emphasises the broad potential applications for lectin-targeted therapies.

Gold(III) complexes in medicinal chemistry.

A number of gold(III) compounds has been designed with the objective of overcoming the disadvantages associated with the platinum-based drugs for cancer treatment. Compounds of a remarkable structural manifold show significant antiproliferative effects in vitro against a number of cancer cells, including cisplatin resistant ones. The target of most of them is, unlike that of cisplatin, not the DNA. Although the mechanisms of action displayed by the gold compounds in biological media are still under investigation, many studies show evidence that the cellular targets are mitochondria-based. Recent advances in gold(III) medicinal chemistry also recommend such compounds for other pharmacological applications such as the treatment of viral or parasitic diseases. The radioactive isotopes (198)Au and (199)Au present potential in radiotherapy.

Beyond platinums: gold complexes as anticancer agents.

The accidental discovery of the anticancer properties of cisplatin in the mid-1960s triggered the development of alternative platinum-based drugs. However, the platinum-based treatment of tumor diseases is massively hampered by severe side-effects and development of resistance. Sulfur-containing biomolecules play a significant role in platinum anticancer chemotherapy because of their high affinity to the platinum(II) ion. Sulfur is involved in the entire metabolic processing of platinum drugs. Strong and irreversible binding of cisplatin to intracellular thiolato ligands is considered a major step of inactivation, and reactions with sulfur donors in proteins are believed to affect enzymatic processes. Consequently, the development of novel metal-based compounds with a pharmacological profile different from that of clinically-established platinum drugs is a major goal of modern medicinal chemistry and drug design. Among the non-platinum antitumor agents, gold(III) complexes have recently gained increasing attention due to their strong tumor cell growth-inhibiting effects, generally achieved by exploiting non-cisplatin-like mechanisms of action. The real breakthrough is not simply the use of gold compounds to treat cancer, but the rational design of gold-based drugs which may be very effective, non-toxic and potentially selective towards cancer cells, their potential impact relying on the possible site-specific delivery in localized cancer, thus strongly improving cellular uptake and minimizing unwanted side-effects. Cancer cells are known to overexpress specific proteins and receptors needed for tumor growth. Among them, two integral plasma membrane proteins mediate the cellular uptake of di- and tripeptides and peptide-like drugs. They are present predominantly in epithelial cells of the small intestine, bile duct, mammary glands, lung, choroid plexus, and kidney but are also localized in other tissues and are up-regulated in some types of tumors. Accordingly, we have been designing gold(III)-peptide dithiocarbamato derivatives which combine both the antitumor properties and reduced side-effects of the previously reported gold(III) analogues with enhanced bioavailability and tumor selectivity achieved by exploiting peptide transporters. Our compounds showed interesting cytotoxic properties towards a number of cancer cell lines in vitro and in vivo on xenograft models, together with negligible organ and acute toxicity. With respect to their mechanisms of action, we identified mitochondria and proteasome as major in vitro and in vivo targets. These results allowed the filing of an international patent for the use of gold(III) peptidomimetics in cancer chemotherapy, as well as providing a solid starting point for them to enter phase I clinical trials in a few months.

The testing of Sanocrysin: science, profit, and innovation in clinical trial design, 1926-31.

This article provides a detailed analysis of the origins and significance of the 1926 clinical trial of Sanocrysin, a gold compound thought at the time to be useful in the treatment of tuberculosis. This experiment is generally considered to be the first clinical trial in the United States that used a formal system of randomization to divide research subjects into treatment and nontreatment groups; it was probably also the first clinical trial in the United States to use placebo shams in a nontreatment control group to overcome the problem of what researchers at the time called "psychic influence." As such, it was an extremely important moment in the history of clinical trial design. Yet, as I argue, the Sanocrysin experiment also needs to be understood in terms of both the regulatory environment at the time and the commercial interests of Parke, Davis & Company, the pharmaceutical manufacturer that was intent on introducing the drug. Although some historians argue that therapeutic reformers in the twentieth century used experimental science to rein in the commercial forces of the market, this article suggests that, at least in this case, the promotion of rigorous clinical science and the pursuit of corporate profit were deeply intertwined.

Protein metalation by metal-based drugs: reactions of cytotoxic gold compounds with cytochrome c and lysozyme.

Protein metalation processes are crucial for the mechanism of action of several anticancer metallodrugs and warrant deeper characterisation. We have explored the reactions of three cytotoxic gold(III) compounds-namely [(bipy(2Me))(2)Au(2)(µ-O)(2)][PF(6)](2) (where bipy(2Me) is 6,6'-dimethyl-2,2'-bipyridine) (Auoxo6), [(phen(2Me))(2)Au(2)(µ-O)(2)][PF(6)](2) (where phen(2Me) is 2,9-dimethyl-1,10-phenanthroline) (Au(2)phen) and [(bipy(dmb)-H)Au(OH)][PF(6)] [where bipy(dmb)-H is deprotonated 6-(1,1-dimethylbenzyl)-2,2'-bipyridine] (Aubipyc)-with two representative model proteins, i.e. horse heart cytochrome c and hen egg white lysozyme, through UV-visible absorption spectroscopy and electrospray ionisation mass spectrometry (ESI MS) to characterise the inherent protein metalation processes. Notably, Auoxo6 and Au(2)phen produced stable protein adducts where one or more "naked" gold(I) ions are protein-coordinated; very characteristic is the case of cytochrome c, which upon reaction with Auoxo6 or Au(2)phen preferentially forms "tetragold" adducts with four protein-bound gold(I) ions. In turn, Aubipyc afforded monometalated protein adducts where the structural core of the gold(III) centre and its +3 oxidation state are conserved. Auranofin yielded protein derivatives containing the intact auranofin molecule. Additional studies were performed to assess the role played by a reducing environment in protein metalation. Overall, the approach adopted provides detailed insight into the formation of metallodrug-protein derivatives and permits trends, peculiarities and mechanistic details of the underlying processes to be highlighted. In this respect, electrospray ionisation mass spectrometry is a very straightforward and informative research tool. The protein metalation processes investigated critically depend on the nature of both the metal compound and the interacting protein and also on the solution conditions used; thus, predicting with accuracy the nature and the amounts of the adducts formed for a given metallodrug-protein pair is currently extremely difficult.

Strategies for the biological evaluation of gold anticancer agents.

Since the introduction of the monomeric orally bioavailable anti-arthritic gold compound auranofin in 1985, and the success of the platinum-based anti-cancer drugs, there has been a great deal of interest in the use of gold compounds for cancer therapy. However this early promise has not materialized into an approved drug in spite of extensive and innovative efforts in gold chemistry. Therefore, in the light of this lack of success, the strategies for the biological evaluation of potential gold-based anti-cancer drugs are discussed. It is proposed that the biological testing strategy should be multi-faceted incorporating an understanding of the molecular properties of the compounds under investigation related to their behaviour in a biological environment, an evaluation of their comparative in vitro potency against tumor cells, ascertaining the biochemical mechanism of action and target identification to aid in medicinal chemistry design, evaluation of in vivo activity in relevant tumor models, and an understanding of their toxicological and pharmacokinetic properties. This strategy will be exemplified with work on Au(III) cyclometallated complexes in which an integrated approach to the search for new metal-based anticancer drugs was adopted, incorporating in vitro screening, in vivo human tumor xenograft models, and mechanistic studies. The importance of mechanistic studies which have led to the identification of new molecular targets for gold drugs, and in vivo evaluation are emphasized.

Gold compounds as therapeutic agents for human diseases.

The application of gold in medicine is traceable for several thousand years and Au(i) compounds have been used clinically to treat rheumatoid arthritis since the last century. Recently research into gold-based drugs for a range of human diseases has seen a renaissance. Old as well as new Au(i) and Au(iii) compounds have been used and designed with an aim of targeting cellular components that are implicated in the onset or progression of cancers, rheumatoid arthiritis, viral and parasitic diseases. In addition, new disease targets have been found for gold compounds that have given insight into the mechanism of action of these compounds, as well as in the molecular pathophysiology of human diseases. Here we discuss the rationale for the design and use of gold compounds that have specific and selective targets in cells to alleviate the symptoms of a range of human diseases. We summarise the most recent findings in this research and our own discoveries to show that gold compounds can be developed to become versatile and powerful drugs for diseases caused by dysfunction of selenol and thiol containing proteins.

[Pemphigus: a review]. / Pemphigus: revue de la littérature.

BACKGROUND: Pemphigus is a rare autoimmune bullous disorder. Numerous treatment regimens have been proposed in the literature. OBJECTIVE: To assess the efficacy and tolerance of treatment regimens proposed in pemphigus vulgaris (PV) and pemphigus foliaceus (PF), from a systematic review of the literature. METHODS: Randomized control trials have been identified using the PubMed and Embase databases up to April 2009. Uncontrolled prospective and retrospective studies have also been analyzed. RESULTS: Eleven randomized control trials having included a total number of 421 patients (377 PV, 44 PF) have been analyzed. Most studies had a limited statistical power due to the rather low number of cases included. Results from ten different treatment regimens have been analyzed: different dosages of prednisone and prednisolone, pulse intravenous dexamethasone, azathioprine, cyclophosphamide, cyclosporine, dapsone, mycophenolate mofetil, plasmapheresis, topical applications of epidermal growth factor (EGF), and intravenous immune globulins (IVIG). Inclusion criteria were: (i) consecutive patients in nine studies, (ii) patients who did not respond to low doses of corticosteroids in one study, and (iii) patients with relapsing type of pemphigus in one study. None of these studies allowed identifying the best effective and well tolerated regimen. Mycophenolate mofetil was more effective than azathioprine for disease control (from one study; n=40; OR=0.72; 95% CI=0.52-0.99). However, no difference in the rate of clinical remission was evidenced between these drugs. Azathioprine and cyclophosphamide seem to have a corticosteroid sparing effect. CONCLUSION: Data from the literature did not allow identifying the best therapeutic regimen, mainly because of the lack of statistical power of most studies. The usefulness of immunosuppressant added to systemic corticosteroids as the first line of treatment is not clearly established.

Microalbuminuria in rheumatoid arthritis in the post penicillamine/gold era: association with hypertension, but not therapy or inflammation.

Rheumatoid arthritis (RA) associates with excess cardiovascular (CV) morbidity and mortality. New screening tools are needed to better identify patients at increased CV risk. Microalbuminuria (MA) has been shown to associate with inflammation and future cardiovascular disease (CVD). In the present study, we assessed the prevalence of MA in a secondary care cohort of RA patients, aimed to identify factors associated with its presence and addressed its relationship to CVD and the metabolic syndrome (MetS). A total of 342 RA patients were studied. MA was defined as an albumin-creatinine ratio ≥22 (males) or ≥31 (females) milligrams per gram creatinine. The independence of the associations of MA was evaluated using binary logistic regression analysis. Prevalence of MA was 11.9%. Subjects with MA had increased prevalence of hypertension (HT), insulin resistance and type 2 diabetes. In binary logistic regression, only HT (OR = 5.22, 95%CI: 1.51-18.07, p = 0.009) was significantly associated with MA. There was no association between prevalent CVD and MA, but patients with MA had twofold increased odds of having the MetS. MA is relatively common in RA patients and is independently associated with the presence of HT. Given the association of MA with MetS, future prospective studies are needed to establish the use of MA as a screening tool for RA patients at increased CVD risk.

[History of gold--with danish contribution to tuberculosis and rheumatoid arthritis]. / Guld i medicinens tjeneste--Med traek af dansk indsats ved tuberkulose og reumatoid artrit.

Gold has a long history as a therapeutic agent, first as gold particles and colloidal gold, then as a soluble salt made by the alchemists, and potable gold was recommended almost as a panacea against different diseases. Gold compounds were introduced in the treatment of tuberculosis, based initially on the reputation of Robert Koch, who found gold cyanide effective against Mycobacterium tuberculosis in cultures. Although several investigations of gold salts showed no convincing effect in experimental tuberculosis in guinea pigs, the idea of using gold compounds as chemotherapy was furthermore encouraged from the work of Paul Ehrlich with arsenicals. The enthusiasm and the craving desperately for a remedy for tuberculosis forced Danish physicians, in the mid-1920s to treat tuberculosis with Sanocrysin (gold sodium thiosulfate). Professor Holger Møllgaard, in collaboration with the clinicians the professors Knud Secher and Knud Faber, was the theoretical promoter of the project. He recommended sanocrysin-antiserum therapy, since sanocrysin caused serious reactions in tuberculosis animals, possible by releasing toxins from tubercle bacilli "killed" by sanocrysin. However the enthusiastic response to sanocrysin in Europe declined along by controlled trials and reports on toxicity in the 1930s. The belief that rheumatoid arthritis was a form of tuberculosis caused a renaissance in chrysotherapy. In France Jacques Forestier obtained encouraging results in the treatment of rheumatoid arthritis with myochrysine and other gold salts, and he pointed out the disease modifying effect of chrysotherapy. In Denmark Knud Secher, who was the clinical initiator of Sanocrysin therapy in tuberculosis, now became the founder of chrysotherapy in rheumatoid arthritis. Although new potential agents are now taking over in the treatment of arthritis, it is still believed, that there is a place for the chrysotherapy. However a new future for gold, in the form of nanoparticles, appears on the horizon, especially in the imaging, diagnostics and therapies of cancer.