Impact of PVC microplastics in photodynamic inactivation of Staphylococcus aureus and MRSA

Photodynamic processes have found widespread application in therapies. These processes involve photosensitizers (PSs) that, when excited by specific light wavelengths and in the presence of molecular oxygen, generate reactive oxygen species (ROS), that target cells leading to inactivation. Photodynamic action has gained notable attention in environmental applications, particularly against pathogens and antibiotic-resistant bacteria (ARB) that pose a significant challenge to public health. However, environmental matrices frequently encompass additional contaminants and interferents, including microplastics (MPs), which are pollutants of current concern. Their presence in water and effluents has been extensively documented, highlighting their impact on conventional treatment methods, but this information remains scarce in the context of photodynamic inactivation (PDI) setups. Here, we described the effects of polyvinyl chloride (PVC) microparticles in PDI targeting Staphylococcus aureus and its methicillin-resistant strain (MRSA), using curcumin as a PS under blue light. The presence of PVC microparticles does not hinder ROS formation; however, depending on its concentration, it can impact bacterial inactivation. Our results underscore that PDI remains a potent method for reducing bacterial concentrations in water and wastewater containing ARB, even in highly contaminated scenarios with MPs.

Influence of temperature combined with photodynamic inactivation on the development of Aedes aegypti

To reduce the speed of selection of populations resistant to chemical insecticides, photodynamic inactivation (PDI) against Aedes aegypti is a hot-topic and promising alternative technique to vector control. Temperature is an important factor in the survival of Ae. aegypti larvae and mosquitoes as it influences physiology, behavior, and ecology. This work aimed to evaluate parameters of the biological cycle of Ae. aegypti such as: hatching rate, larval development, adult mosquito longevity, sex ratio, weight, and lethal concentration of larval mortality (LC) through the combination of PDI with different temperatures. The number of larvae found after 48 h suggests that temperature affects hatching rate. Additionally, results showed a delay in development of surviving larvae after PDI when compared to control groups, and there was a reduction in the longevity of mosquitoes that undertook photodynamic action. PDI also led to a predominance of male insects, and observed weight indicates that the inactivation method may have also interfered in mosquito size. The results point to a satisfactory performance of PDI at all tested temperatures. Experimental conditions that were not lethal to all larvae implied that PDI impacts the mosquitoes' biological cycle. Though metabolism and development are improved at higher temperatures, so is PDI action, thus maintaining the net benefit. Therefore, it is assumed that the proposed photolarvicide can be useful in reducing arbovirus transmission, and results invite for future research in different abiotic conditions.

Hydrogen peroxide preoxidation as a strategy for enhanced antimicrobial photodynamic action against methicillin-resistant Staphylococcus aureus

Antimicrobial photodynamic treatment (aPDT) is a photooxidative process based on the excitation of a photosensitizer (PS) in the presence of molecular oxygen, under specific wavelengths of light. It is a promising method for advanced treatment of water and wastewater, particularly targeting disinfection challenges, such as antibiotic-resistant bacteria (ARB). Research in improved aPDT has been exploring new PS materials, and additives in general. Hydrogen peroxide (H2O2) a widely applied disinfectant, mostly in the food industry and clinical settings, present environmentally negligible residuals at the usually applied concentrations, making it friendly for the water and wastewater sectors. Here, we explored the effects of preoxidation with H2O2 followed by blue light-mediated (450 nm) aPDT using curcumin (a natural-based PS) against methicillin-resistant Staphylococcus aureus (MRSA). Results of the sequential treatment pointed to a slight hampering in aPDT efficiency at very low H2O2 concentrations, followed by an increasing cooperative effect up to a deleterious point (≥7 log10 inactivation in CFU mL-1), suggesting a synergistic interaction of preoxidation and aPDT. The increased performance in H2O2-pretreated aPDT encourages studies of optimal operational conditions for the assisted technology and describes potentials for using the described strategy to tackle the issue of ARB spread.

Photon spectra effects tested on the vegetal model Allium cepa

The use of artificial light sources in plants is considered a type of photobiomodulation (PBM), a trend in agriculture and food industries, aiming at decontamination, pest control, and increased production yield. However, literature lacks a broader assessment to address the effects of photon light spectra on plant characteristics. Here, we aimed to describe the effects of visible light, infrared, and ultraviolet light upon Allium cepa, a known bioindicator, under various light doses. Samples irradiated under visible and infrared light did not show cytotoxicity, genotoxicity, or mutagenicity in any of the evaluated doses. Light induction at 460 and 635 nm significantly stimulated root development of the test organism. In contrast, 254 nm irradiation proved to be cytotoxic, genotoxic, and mutagenic. This work reveals and quantifies the spectral response of A. cepa seeds, suggesting that it can be proposed as a model for future research on mechanisms of PBM in plants.

Alternative Controlling Agent of Theobroma grandiflorum Pests: Nanoscale Surface and Fractal Analysis of Gelatin/PCL Loaded Particles Containing Lippia origanoides Essential Oil

A new systematic structural study was performed using the Atomic Force Microscopy (AFM) reporting statistical parameters of polymeric particles based on gelatin and poly-ε-caprolactone (PCL) containing essential oil from Lippia origanoides. The developed biocides are efficient alternative controlling agents of Conotrachelus humeropictus and Moniliophtora perniciosa, the main pests of Theobroma grandiflorum. Our results showed that the particles morphology can be successfully controlled by advanced stereometric parameters, pointing to an appropriate concentration of encapsulated essential oil according to the particle surface characteristics. For this reason, the absolute concentration of 1000 µg·mL^-1 (P₁₀₀₀ system) was encapsulated, resulting in the most suitable surface microtexture, allowing a faster and more efficient essential oil release. Loaded particles presented zeta potential around (-54.3 ± 2.3) mV at pH = 8, and particle size distribution ranging from 113 to 442 nm. The hydrodynamic diameter of 90% of the particle population was found to be up to (405 ± 31) nm in the P₁₀₀₀ system. The essential oil release was evaluated up to 80 h, with maximum release concentrations of 63% and 95% for P₅₀₀ and P₁₀₀₀, respectively. The best fit for the release profiles was obtained using the Korsmeyer-Peppas mathematical model. Loaded particles resulted in 100% mortality of C. humeropictus up to 48 h. The antifungal tests against M. perniciosa resulted in a minimum inhibitory concentration of 250 µg·mL^-1, and the P₁₀₀₀ system produced growth inhibition up to 7 days. The developed system has potential as alternative controlling agent, due to its physical stability, particle surface microtexture, as well as pronounced bioactivity of the encapsulated essential oil.

Pulsatile Controlled Release and Stability Evaluation of Polymeric Particles Containing Piper nigrum Essential Oil and Preservatives

Considerable efforts have been spent on environmentally friendly particles for the encapsulation of essential oils. Polymeric particles were developed to encapsulate the essential oil from Piper nigrum based on gelatin and poly-ε-caprolactone (PCL) carriers. Gas Chromatography ((Flame Ionization Detection (GC/FID) and Mass Spectrometry (GC/MS)), Atomic Force Microscopy (AFM), Nanoparticle Tracking Analysis (NTA), Confocal Laser Scanning Microscopy (CLSM), Attenuated Total Reflectance-Fourier-transform Infrared Spectroscopy (ATR-FTIR), and Ultraviolet-Visible (UV-VIS) spectroscopy were used for the full colloidal system characterization. The essential oil was mainly composed of β-caryophyllene (~35%). The stability of the encapsulated systems was evaluated by Encapsulation Efficiency (EE%), electrical conductivity, turbidity, pH, and organoleptic properties (color and odor) after adding different preservatives. The mixture of phenoxyethanol/isotialzoni-3-one (PNE system) resulted in enhanced stability of approximately 120 and 210 days under constant handling and shelf-life tests, respectively. The developed polymeric system presented a similar controlled release in acidic, neutral, or basic pH, and the release curves suggested a pulsatile release mechanism due to a complexation of essential oil in the PCL matrix. Our results showed that the developed system has potential as an alternative stable product and as a controlling agent, due to the pronounced bioactivity of the encapsulated essential oil.

Photoinactivation of Aedes aegypti larvae using riboflavin as photosensitizer

More than half of the global population lives in areas where the Aedes aegypti mosquito is present. Efforts have been made to deal with the population of this mosquito in the larval and adult stages to prevent outbreaks of diseases (Dengue, Zika, Chikungunya, and Yellow Fever). In this scenario, photodynamic inactivation may be an effective alternative method to control this vector population. To evaluate the efficacy of the riboflavin - B2 vitamin - as photosensitizer (PS) in the photodynamic inactivation of Ae. aegypti larvae, different concentrations (0; 0.005; 0.010; 0.025; 0.050; 0.075 and 0.100 mg mL^-1) were evaluated under white light from RGB LEDs at a light dose of 495.2 J cm^-2. The results reveal that riboflavin can be successfully applied as a PS agent to photoinactivate Ae. aegypti larvae, showing its potential to deal with the larvae population.

Photodynamic control of Aedes aegypti larvae with environmentally-friendly tetra-platinated porphyrin

This work evaluated the photosensitizing activity of isomeric tetra-cationic porphyrins with peripheral [Pt(bpy)Cl]⁺ to control the larval population of Aedes aegypti by photodynamic action. The photolarvicidal activity of the tetra-platinated porphyrins at meta and para position (3-PtTPyP and 4-PtTPyP) was evaluated under blue (450 nm), green (525 nm), and red (625 nm) light illumination at 55.0 J cm^-2. The meta isomer presented an efficient photolarvicidal activity even at a low concentration (1.2 ppm) in the presence of light, while the para counterpart was inactive regardless of the concentration and illumination. The different responses were related to the improved optical features and higher water solubility of 3-PtTPyP compared to 4-PtTPyP. Additionally, the potential environmental toxicity of 3-PtTPyP was tested in a plant model (Allium cepa test), with no toxicity detected for all used concentrations (1.2 to 12 ppm). Hence, this work reveals that 3-PtTPyP has a great potential to be employed to photodynamically control the insect vector population in an environmentally safe way.

The mixture of cashew nut shell liquid and castor oil results in an efficient larvicide against Aedes aegypti that does not alter embryo-fetal development, reproductive performance or DNA integrity

Dengue fever, chikungunya fever and Zika virus are epidemics in Brazil that are transmitted by mosquitoes, such as Aedes aegypti or Aedes albopictus. The liquid from shells of cashew nuts is attractive for its important biological and therapeutic activities, which include toxicity to mosquitoes of the genus Aedes. The present study evaluated the effects of a mixture of surfactants from natural cashew nutshell liquid and castor oil (named TaLCC-20) on the mortality of larvae and on the reproductive performance, embryonic and fetal development and genetic stability of Swiss mice. A total of 400 Ae. aegypti larvae (third larval stage) were treated with TaLCC-20 concentrations of 0.05 mg/L, 0.5 mg/L, or 5 mg/L (ppm). Twenty pregnant female mice were also orally administered TaLCC-20 at doses of 5 mg/kg and 50 mg/kg body weight (b.w.), and 10 animals were given only drinking water at 0.1 mL/10 g b.w. (orally). The results of a larvicide test demonstrated that 5 mg/mL TaLCC-20 killed 100% of larvae within three hours, which is comparable to the gold standard indicated by the Ministry of Health. Overall, these results show that TaLCC-20 is an efficient larvicide that does not induce genetic damage. In addition, changes in reproductive performance and embryo-fetal development appear positive, and the formulation is cost effective. Therefore, TaLCC-20 is an important product in the exploration of natural larvicides and can assist in fighting mosquitos as vectors for dengue fever, chikungunya fever and Zika virus, which are emerging/re-emerging and require proper management to ensure minimal harm to the human population. Therefore, TaLCC-20 can be considered a key alternative to commercial products, which are effective yet toxigenic.

Anatomic study of the collateral branches of the abdominal aorta of primate species Saguinus niger

Saguinus niger is a primate of the family Callitrichidae, with a geographical distribution limited to northern Brazil, Guyanas, Suriname and Venezuela, where it inhabits rainforests along the coast. Three adult females from the Paragominas Bauxite Mine--PA were used, donated to the Laboratory of Animal Morphology Research (LAMR) of the Federal Rural University of Amazonia. These animals had died of natural causes. The arterial system was filled with latex, and the animals were fixed in 10% formalin. Afterwards, the abdominal aorta and its collateral branches were dissected. The arrangement of the abdominal aorta branches in this species showed a similar arrangement as domestic animals but differing in the formation of the coeliac trunk. The coeliac trunk originates from the abdominal aorta, and from this trunk, we found the hepatic, left gastric and splenic arteries, where the origin of these vessels was variable. These arteries originate from the coliac trunk or a common trunk originating from the coeliac trunk, a characteristic not described in other species. The other branches of the abdominal aorta from S. niger did not show great differences in origin when compared to other species.

Anticholinergics for neuroleptic-induced acute akathisia

BACKGROUND

Neuroleptic-induced akathisia is one of the most common and distressing early-onset adverse effects of conventional antipsychotic drugs, being associated with poor compliance with treatment, and thus, ultimately, with an increased risk of relapse. This review assesses the role of anticholinergic drugs as an adjunct to standard antipsychotic medication in the pharmacological treatment of this problem.

OBJECTIVES

To determine the clinical effects of anticholinergic drugs for neuroleptic-induced acute akathisia.

SEARCH STRATEGY

The reviewers undertook electronic searches of Biological Abstracts (1982-1999), CINAHL (1982-1999), Cochrane Library (Issue 4 1999), Cochrane Schizophrenia Group's Register (October 1999), EMBASE (1980-1999), LILACS (1982-1999), MEDLINE (1966-1999) and PsycLIT (1974-1999). References of all identified studies were inspected for more trials and first authors contacted. Each included study was sought as a citation on the Science Citation Index database.

SELECTION CRITERIA

All randomised clinical trials of anticholinergic drugs versus placebo for people with neuroleptic-induced acute akathisia.

DATA COLLECTION AND ANALYSIS

Two reviewers, working independently, selected, quality assessed and extracted data. These data were then analysed on an intention-to-treat basis. For homogeneous dichotomous data the fixed effects relative risk (RR), the 95% confidence intervals (CI) and, where appropriate, the number needed to treat (NNT) were calculated on an intention-to-treat basis. For continuous data, reviewers calculated weighted mean differences.

MAIN RESULTS

No randomised controlled trials could be included.

REVIEWER'S CONCLUSIONS

At present, there is no reliable evidence to support or refute the use of anticholinergics for people suffering from neuroleptic-induced acute akathisia. Akathisia is a most distressing movement disorder that remains highly prevalent, both in the developed and developing world. This review highlights the need for well designed, conducted and reported clinical trials to address the claims of open studies as regards the effects of the anticholinergic group of drugs for akathisia.

Anticholinergics for neuroleptic-induced acute akathisia

BACKGROUND

Neuroleptic-induced akathisia is one of the most common and distressing early-onset adverse effects of conventional antipsychotic drugs, being associated with poor compliance with treatment, and thus, ultimately, with an increased risk of relapse. This review assesses the role of anticholinergic drugs as an adjunct to standard antipsychotic medication in the pharmacological treatment of this problem.

OBJECTIVES

To determine the clinical effects of anticholinergic drugs for neuroleptic-induced acute akathisia.

SEARCH STRATEGY

The reviewers undertook electronic searches of Biological Abstracts (1982-1999), CINAHL (1982-1999), Cochrane Library (Issue 4 1999), Cochrane Schizophrenia Group's Register (October 1999), EMBASE (1980-1999), LILACS (1982-1999), MEDLINE (1966-1999) and PsycLIT (1974-1999). References of all identified studies were inspected for more trials and first authors contacted. Each included study was sought as a citation on the Science Citation Index database.

SELECTION CRITERIA

All randomised clinical trials of anticholinergic drugs versus placebo for people with neuroleptic-induced acute akathisia.

DATA COLLECTION AND ANALYSIS

Two reviewers, working independently, selected, quality assessed and extracted data. These data were then analysed on an intention-to-treat basis. For homogeneous dichotomous data the fixed effects relative risk (RR), the 95% confidence intervals (CI) and, where appropriate, the number needed to treat (NNT) were calculated on an intention-to-treat basis. For continuous data, reviewers calculated weighted mean differences.

MAIN RESULTS

No randomised controlled trials could be included.

REVIEWER'S CONCLUSIONS

At present, there is no reliable evidence to support or refute the use of anticholinergics for people suffering from neuroleptic-induced acute akathisia. Akathisia is a most distressing movement disorder that remains highly prevalent, both in the developed and developing world. This review highlights the need for well designed, conducted and reported clinical trials to address the claims of open studies as regards the effects of the anticholinergic group of drugs for akathisia.

Benzodiazepines for neuroleptic-induced acute akathisia

BACKGROUND

Neuroleptic-induced akathisia is one of the most common and distressing early-onset adverse effects of antipsychotic drugs, being associated with poor compliance with treatment, and thus, ultimately, to an increase risk of relapse. This review assesses the role of benzodiazepines in the pharmacological treatment of this problem.

OBJECTIVES

To determine the effects of benzodiazepines versus placebo for people with neuroleptic-induced acute akathisia.

SEARCH STRATEGY

Biological Abstracts (January 1982-March 1999), The Cochrane Library (Issue 3 1999), The Cochrane Schizophrenia Group's Register (May 2001), EMBASE (January 1980-March 1999), LILACS (January 1982-March 1999), MEDLINE (January 1964-March 1999), PsycLIT (January 1974-March 1999), and SCISEARCH were searched. Further references were sought from published trials and their authors.

SELECTION CRITERIA

All randomised clinical trials comparing benzodiazepines with placebo for people with antipsychotic-induced acute akathisia.

DATA COLLECTION AND ANALYSIS

Two reviewers, working independently, selected, quality assessed and extracted data. These data were then analysed on an intention-to-treat basis. For homogeneous dichotomous data the fixed effects relative risk (RR), the 95% confidence intervals (CI) and, where appropriate, the number needed to treat (NNT) were calculated on an intention-to-treat basis. For continuous data, reviewers calculated weighted mean differences.

MAIN RESULTS

Two small (total N=27) randomised controlled trials were included. By seven to 14 days, there was a reduction in symptoms for those patients receiving clonazepam compared with placebo (2 RCTs, N=26, RR 0.09 CI 0.01 to 0.6, NNT 1.2 CI 0.9 to 1.5). No significant difference was found for adverse events (2 RCTs, N=26, RR 3.00 CI 0.2 to 62) or the need for anticholinergic medication (2 RCTs, N=26, RR 1.56 CI 0.9 to 2.7). No one left the two studies early. Data on mental, social and family outcomes could not be pooled and there was little or no data on user satisfaction, deaths, violence, criminal behaviour and costs.

REVIEWER'S CONCLUSIONS

Over a short follow-up period, the use of benzodiazepines may reduce the symptoms of antipsychotic-induced acute akathisia. This review highlights the need for well designed, conducted and reported clinical trials to address the claims of open studies.

Carbamazepine for cocaine dependence

BACKGROUND

Cocaine dependence has become a substantial public health problem, developing a significant number of medical, psychological and social problems, including the spread of infectious diseases (e.g. AIDS, hepatitis and tuberculosis), crime, violence and neonatal drug exposure. Although there is no consensus regarding how to treat cocaine dependence, effective pharmacotherapy has a potentially major role to play as part of a broader treatment milieu. The anti-convulsant carbamazepine, a tricyclic medication that is widely used to treat a variety of neurological and psychiatric disorders, has also been used for treatment of cocaine dependence, although its effectiveness has not been established.

OBJECTIVES

To determine whether carbamazepine (CBZ) is effective for the treatment of cocaine dependence.

SEARCH STRATEGY

We searched: the Cochrane Controlled Trials Register (Cochrane Library issue 1, 1999), MEDLINE (from 1966 - October 1997), EMBASE (from 1980 - October 1997), PsycLIT (from 1974 - July 1997), Biological Abstracts and LILACS (from 1982 - 1997); scan of reference list of relevant articles; personal communication; conference abstracts; unpublished trials from pharmaceutical industry; book chapters on treatment of cocaine dependence.

SELECTION CRITERIA

The inclusion criteria for all randomised controlled trials were that they should focus on the use of carbamazepine drugs versus placebo on the treatment of cocaine dependence. Trials including patients with additional diagnosis such as opiate dependence were also eligible.

DATA COLLECTION AND ANALYSIS

The reviewers extracted the data independently and Odds Ratios, weighted mean difference and number needed to treat were estimated. Qualitative assessments of the methodology of eligible studies were carried out using validated checklists. The reviewers assumed that people who died or dropped out had no improvement and tested the sensitivity of the final results to this assumption. Where possible analysis was carried out according to the "intention to treat" principles.

MAIN RESULTS

5 studies were included in the review, with 455 people randomised. No differences were found regarding positive urine sample for cocaine metabolites. Scores on Spielberg State Anxiety Inventory slightly favoured carbamazepine, but didn't reach statistical significance. Dropouts were high in both groups up to 70% in the placebo group. Less dropout occurred in the carbamazepine group (RR 0.87 95%CI 0.71-1.06). When no retention in treatment was due to side effects no differences were found. The number of participants presenting at least one side effect, reported in Kranzler (Kranzler 1995), was higher in the carbamazepine group (RR 4.33 95% CI 1.45-12.91).

REVIEWER'S CONCLUSIONS

There is no current evidence supporting the clinical use of CBZ in the treatment of cocaine dependence. Larger randomised investigation must be considered taking into account that these time-consuming efforts should be reserved for medications showing more relevant and promising evidence.

Tamanho da Partícula do Milho e Forma Física da Ração e Seus Efeitos Sobre o Desempenho e Rendimento de Carcaça de Frangos de Corte

Este experimento foi realizado com o objetivo de investigar os efeitos de diferentes granulometrias, expressa em Diâmetro Geométrico Médio (DGM) do milho (0,336mm, 0,585mm, 0,856 mm e 1,12 mm) de dietas fornecidas na forma farelada (FAR) e peletizada (PEL), no desempenho e no rendimento de carcaça e de cortes de frangos de corte de 21 a 42 dias de idade. Dietas FAR, produzidas com DGM de 0,336 mm resultaram em um menor consumo (p<0,001), ganho de peso (p<0,001) e pior conversão alimentar (p<0,001) do que as PEL de mesmo DGM. Os demais DGM não mostraram diferenças entre ração FAR e PEL. Quando avaliada somente a granulometria, observou-se que o aumento no DGM melhorou o ganho de peso linearmente e de forma quadrática o consumo e a conversão alimentar. Não houve influência da forma física ou DGM em rendimento de carcaça e rendimento de perna+coxa. Porém foi verificada uma redução em rendimento de peito com DGM 0,336 mm (p<0,001), na forma FAR.

Entropy-based analysis of the number partitioning problem

In this paper we apply the multicanonical method of statistical physics on the number partitioning problem (NPP). This problem is a basic NP-hard problem from computer science, and can be formulated as a spin-glass problem. We compute the spectral degeneracy, which gives us information about the number of solutions for a given cost E and cardinality difference m. We also study an extension of this problem for Q partitions. We show that a fundamental difference on the spectral degeneracy of the generalized (Q>2) NPP exists, which could explain why it is so difficult to find good solutions for this case.

[Caring for patients with Hickman-Broviac catheters: a case study]

Caring the patient with Hickman-Broviac catheter: a case study. The authors make a short literature review about the Hickman-Broviac catheter and after they analyse and comment about the nursing staff's knowledge and patient's self care related to this catheter.

An ultrasonographic study of liver fibrosis in patients infected with Schistosoma mansoni in north-east Brazil

Between August 1988 and July 1990, 176 patients with Schistosoma mansoni infection attending the University Hospital, Recife, Brazil received a complete clinical examination including stool examination for intestinal parasites, liver function tests, and ultrasonography. The majority were also examined by upper digestive tract endoscopy. The clinical distribution of their disease was as follows: 26.7% intestinal, 13.6% hepato-intestinal, 53.4% compensated hepatosplenic and 6.3% decompensated hepatosplenic. Infection intensity was high, with a median of 360 eggs/g of faeces. Ultrasonography showed a good correlation between the degree of hepatic periportal fibrosis and the clinical stage of disease (P < 0.0001). Of the patients with the intestinal form of schistosomiasis, 12.8% had grade I fibrosis and the others had no fibrosis; 33.3% of patients with hepatointestinal schistosomiasis had grade I fibrosis, 8.3% had grade II fibrosis, and 58.4% had no fibrosis; all the patients with hepatosplenic disease had grade II or grade III fibrosis. The degree of liver fibrosis detected by ultrasonography correlated with the degree of oesophageal varices detected by endoscopy (P = 0.0001). The degree of oesophageal varices also correlated with the presence of haemorrhage (P < 0.0001). Ultrasonography is considered superior to liver biopsy, permitting a dynamic approach to the study of schistosomiasis morbidity with precise diagnosis and simple sequential follow-up of post-treatment results.