An environmentally benign antimicrobial nanoparticle based on a silver-infused lignin core

Silver nanoparticles have antibacterial properties, but their use has been a cause for concern because they persist in the environment. Here, we show that lignin nanoparticles infused with silver ions and coated with a cationic polyelectrolyte layer form a biodegradable and green alternative to silver nanoparticles. The polyelectrolyte layer promotes the adhesion of the particles to bacterial cell membranes and, together with silver ions, can kill a broad spectrum of bacteria, including Escherichia coli, Pseudomonas aeruginosa and quaternary-amine-resistant Ralstonia sp. Ion depletion studies have shown that the bioactivity of these nanoparticles is time-limited because of the desorption of silver ions. High-throughput bioactivity screening did not reveal increased toxicity of the particles when compared to an equivalent mass of metallic silver nanoparticles or silver nitrate solution. Our results demonstrate that the application of green chemistry principles may allow the synthesis of nanoparticles with biodegradable cores that have higher antimicrobial activity and smaller environmental impact than metallic silver nanoparticles

Depression among women living in the outskirts of São Paulo, Southeastern Brasil

OBJECTIVE: To assess the meaning of depression in women diagnosed with the disorder, and the context of care given by the psychiatrists who follow them up. METHODS: Qualitative study performed in Embu, outskirt of São Paulo, between August 2002 and January 2003. Etnographic observation and in-depth interview were carried out with 16 women diagnosed with depression in primary care, and four psychiatrists. After exhaustive reading, data were grouped into categories and assessed. The assessment of outcomes was based on the concept of culture. RESULTS: Women interviewed are well aware of the disorder, and accept treatment based on medication. For psychiatrists, depression is a term understood by the common sense. All women interviewed identified the onset of the disease from a past event such as: death of a son, violent episodes connected with drug traffic, unemployment, and partners' aggressiveness. Violence was common in the every day life of the interviewed women both inside and outside their homes. CONCLUSIONS: For these women, depression is a way to express their feelings, such as unhappiness in a context of poverty and violence. Psychiatrists go beyond their clinical functions and play an important role on reorganizing the daily life of these women.OBJETIVO: Analisar o significado da depressão para mulheres diagnosticadas com o transtorno e o contexto do atendimento realizado pelos psiquiatras que as acompanham. MÉTODOS: Estudo qualitativo realizado no município de Embu, na Grande São Paulo, entre agosto de 2002 e janeiro de 2003. Foram realizadas observação etnográfica e entrevistas em profundidade com 16 mulheres diagnosticadas com depressão, pacientes de uma Unidade Básica de Saúde, e quatro psiquiatras. Após a leitura exaustiva, os dados foram agrupados em categorias e analisados. A interpretação dos resultados baseou-se no conceito de cultura. RESULTADOS: As entrevistadas tinham ampla noção do transtorno, aceitando o tratamento com medicação. Para os psiquiatras, a depressão é um termo assimilado pelo senso-comum. Todas as entrevistadas identificaram a origem da doença em eventos passados, como: morte de filho, episódios violentos ligados ao tráfico de drogas, desemprego e agressividade do companheiro. A violência era comum no cotidiano das entrevistadas, tanto fora como dentro de casa. CONCLUSÕES: Para essas mulheres, a depressão era uma forma de expressar sentimentos, como a infelicidade num contexto de pobreza e violência. Os psiquiatras extrapolam as suas funções clínicas e têm um papel na reorganização do cotidiano dessas mulheres.Universidade Católica de Santos Programa de Mestrado em Saúde ColetivaUniversidade Federal de São Paulo (UNIFESP) Departamento de PsiquiatriaUNIFESP, Depto. de PsiquiatriaSciEL

The attitudes and beliefs of Pakistani medical practitioners about depression: a cross-sectional study in Lahore using the Revised Depression Attitude Questionnaire (R-DAQ)

BACKGROUND: Mental disorders such as depression are common and rank as major contributors to the global burden of disease. Condition recognition and subsequent management of depression is variable and influenced by the attitudes and beliefs of clinicians as well as those of patients. Most studies examining health professionals' attitudes have been conducted in Western nations; this study explores beliefs and attitudes about depression among doctors working in Lahore, Pakistan. METHODS: A cross-sectional survey conducted in 2015 used a questionnaire concerning demographics, education in psychiatry, beliefs about depression causes, and attitudes about depression using the Revised Depression Attitude Questionnaire (R-DAQ). A convenience sample of 700 non-psychiatrist medical practitioners based in six hospitals in Lahore was approached to participate in the survey. RESULTS: Six hundred and one (86 %) of the doctors approached consented to participate; almost all respondents (99 %) endorsed one of various biopsychosocial causes of depression (38 to 79 % for particular causes), and 37 % (between 13 and 19 % for particular causes) noted that supernatural forces could be responsible. Supernatural causes were more commonly held by female doctors, those working in rural settings, and those with greater psychiatry specialist education. Attitudes to depression were mostly less confident or optimistic and less inclined to a generalist perspective than those of clinicians in the UK or European nations, and deterministic perspectives that depression is a natural part of aging or due to personal failings were particularly common. However, there was substantial confidence in the efficacy of antidepressants and psychological therapy. More confident and therapeutically optimistic views and a more generalist perspective about depression management were associated with a rejection of supernatural explanations of the origin of depression. CONCLUSIONS: Non-psychiatrist medical practitioners in Pakistan hold a range of views about the causes of depression, with supernatural explanations held by more than a third. Depression attitudes appear less positive than among UK and European clinicians, with the notions that depression is due to a lack of stamina and will-power and a natural part of growing old being especially commonly held; more positive attitudes appear to be associated with a rejection of supernatural explanatory models of depression

DSM-5: a collection of psychiatrist views on the changes, controversies, and future directions

The recent release of the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) by the American Psychiatric Association has led to much debate. For this forum article, we asked BMC Medicine Editorial Board members who are experts in the field of psychiatry to discuss their personal views on how the changes in DSM-5 might affect clinical practice in their specific areas of psychiatric medicine. This article discusses the influence the DSM-5 may have on the diagnosis and treatment of autism, trauma-related and stressor-related disorders, obsessive-compulsive and related disorders, mood disorders (including major depression and bipolar disorders), and schizophrenia spectrum disorders