Soil Organic Matter Molecular Composition Shifts Driven by Forest Regrowth or Pasture after Slash-and-Burn of Amazon Forest.

Slash-and-burn of Amazon Forest (AF) for pasture establishment has increased the occurrence of AF wildfires. Recent studies emphasize soil organic matter (SOM) molecular composition as a principal driver of post-fire forest regrowth and restoration of AF anti-wildfire ambience. Nevertheless, SOM chemical shifts caused by AF fires and post-fire vegetation are rarely investigated at a molecular level. We employed pyrolysis-gas chromatography-mass spectrometry to reveal molecular changes in SOM (0-10, 40-50 cm depth) of a slash-burn-and-20-month-regrowth AF (BAF) and a 23-year Brachiaria pasture post-AF fire (BRA) site compared to native AF (NAF). In BAF (0-10 cm), increased abundance of unspecific aromatic compounds (UACs), polycyclic aromatic hydrocarbons (PAHs) and lipids (Lip) coupled with a depletion of polysaccharides (Pol) revealed strong lingering effects of fire on SOM. This occurs despite fresh litter deposition on soil, suggesting SOM minimal recovery and toxicity to microorganisms. Accumulation of recalcitrant compounds and slow decomposition of fresh forest material may explain the higher carbon content in BAF (0-5 cm). In BRA, SOM was dominated by Brachiaria contributions. At 40-50 cm, alkyl and hydroaromatic compounds accumulated in BRA, whereas UACs accumulated in BAF. UACs and PAH compounds were abundant in NAF, possibly air-transported from BAF.

From field to laboratory: isolation, genetic assessment, and parasitological behavior of Schistosoma mansoni obtained from naturally infected wild rodent Holochilus sciureus (Rodentia, Cricetidae), collected in Northeastern Brazil.

Wild rodent species are naturally infected by Schistosoma mansoni; however, the genetic characterization of the parasite, its parasitological features, and its role in human schistosomiasis are poorly understood. In this study, we isolated and characterized Schistosoma from naturally infected Holochilus sciureus, called HS strain, collected from a schistosomiasis endemic region in Maranhão State, Brazil. To isolate the parasite, miracidia obtained from the livers of H. sciureus were used to infect Biomphalaria glabrata of sympatric (called SB) and allopatric (called BH) strains, and the produced cercariae were subcutaneously inoculated into hamsters and/or BALB/c mice. Parasitological kinetics in experimentally infected hosts were evaluated, and the tRNACys-12S (referred to as 16S herein) and cox 1 regions of mtDNA from isolated worms were amplified and sequenced. Only miracidia obtained from infected mice, but not from hamsters, were capable of infecting B. glabrata, allowing maintenance of the isolated parasite. Cox1 and 16S mtDNA sequences showed 100% similarity with S. mansoni, and phylogenetic analysis showed that the HS strain of S. mansoni forms an assemblage with isolates from America and Kenya, confirming the conspecificity. Experimental infection of B. glabrata SB with S. mansoni HS resulted in two peaks of cercariae shedding at 45 and 70 days post-infection (dpi) and caused higher mortality than in B. glabrata BH. The worm recovery rate in mice was approximately 13%, and the peak of egg elimination occurred at the 10th week post-infection. Therefore, S. mansoni obtained from H. sciureus was successfully isolated, genetically characterized, and maintained in mice, allowing further study of this schistosome strain.

The Meaning of Suicidal Behaviour for Portuguese Nursing Students.

BACKGROUND: The nursing perspectives on suicidal behaviors may influence the quality of assistance and suicidal prevention. This phenomenon is scarcely investigated among nursing students. AIMS: The aim of this study is to understand the meanings of suicidal behavior for Portuguese undergraduate students. METHODS: This qualitative study utilized Grounded Theory and Symbolic Interactionism. We collected data in Portugal in 2017-2018 with 13 undergraduate students. RESULTS: Students compared suicidal behavior to "A complex and close haze" and considered it "A neglected phenomenon". Suicidal behavior was predominantly perceived as an emotional distress that requires assistance. The students compared the person and society as "The car and the road: behavior influenced by communication and interaction" and valorized social dimensions and repercussions of suicidal behavior. LIMITATIONS: Lack of triangulation in the data and the sampling restricted to nursing students of a single institution are considered limitations of this study. CONCLUSIONS: This study can contribute to the development of academic education strategies and psychosocial support for nursing students.

Refined Chelator Spacer Moieties Ameliorate the Pharmacokinetics of PSMA-617.

Prostate-specific membrane antigen (PSMA) binding tracers are promising agents for the targeting of prostate tumors. To further optimize the clinically established radiopharmaceutical PSMA-617, novel PSMA ligands for prostate cancer endoradiotherapy were developed. A series of PSMA binding tracers that comprise a benzyl group at the chelator moiety were obtained by solid-phase synthesis. The compounds were labeled with 68Ga or 177Lu. Competitive cell-binding assays and internalization assays were performed using the cell line C4-2, a subline of the PSMA positive cell line LNCaP (human lymph node carcinoma of the prostate). Positron emission tomography (PET) imaging and biodistribution studies were conducted in a C4-2 tumor bearing BALB/c nu/nu mouse model. All 68Ga-labeled ligands were stable in human serum over 2 h; 177Lu-CA030 was stable over 72 h. The PSMA ligands revealed inhibition potencies [Ki] (equilibrium inhibition constants) between 4.8 and 33.8 nM. The percentage of internalization of the injected activity/106 cells of 68Ga-CA028, 68Ga-CA029, and 68Ga-CA030 was 41.2 ± 2.7, 44.3 ± 3.9, and 53.8 ± 5.4, respectively; for the comparator 68Ga-PSMA-617, 15.5 ± 3.1 was determined. Small animal PET imaging of the compounds showed a high tumor-to-background contrast. Organ distribution studies revealed high specific uptake in the tumor, that is, approximately 34.4 ± 9.8% of injected dose per gram (%ID/g) at 1 h post injection for 68Ga-CA028. At 1 h p.i., 68Ga-CA028 and 68Ga-CA030 demonstrated lower kidney uptake than 68Ga-PSMA-617, but at later time points, kidney time-activity curves converge. In line with the preclinical data, first diagnostic PET imaging using 68Ga-CA028 and 68Ga-CA030 revealed high-contrast detection of bone and lymph node lesions in patients with metastatic prostate cancer. The novel PSMA ligands, in particular CA028 and CA030, are promising agents for targeting PSMA-positive tumor lesions as shown in the preclinical evaluation and in a first patient, respectively. Thus, clinical translation of 68Ga-CA028 and 68Ga/177Lu-CA030 for diagnostics and endoradiotherapy of prostate cancer in larger cohorts of patients is warranted.

The alien octocoral Carijoa riisei is a biogenic substrate multiplier in artificial Brazilian shipwrecks.

Despite the obvious negative effects caused by invasive species, some recent studies have shown that the impacts at local scale are diverse and not necessarily negative. Arborescent benthic organisms such as octocorals form three-dimensional structures capable of increasing the amount of substrate available and providing shelter for epibiont species. We investigated the role of the alien octocoral Carijoa riisei on the diversity of benthic communities in three shipwrecks on the north-eastern coast of Brazil. We expected that (a) the fauna associated with the octocoral are richer and more diverse compared to the adjacent; (b) some species are exclusively associated with C. riisei; (c) the species that are present both in the areas with and without C. riisei have a greater abundance when associated with the octocoral. For this, we compared the macrobenthic communities associated with C. riisei to those found in adjacent areas where the octocoral was absent. Our study showed that the communities associated with the octocoral were 1.5 times richer and 10 times more abundant than adjacent communities, with 29 exclusive taxa. The dominant taxa were the amphipods Ericthonius brasiliensis and Podocerus brasiliensis and polychaetes of the family Syllidae. These taxa were present in areas with presence and absence of C. riisei, but their abundance was significantly greater where the octocoral was present. Our results reinforce the idea that Carijoa riisei acts as an ecosystem engineer in coastal reefs, creating new habitats and increasing diversity at a local scale, even though it is an alien species.

Adolescents with suicidal behaviours: A qualitative study about the assessment of Inpatient Service and Transition to Community.

WHAT IS KNOWN ON THE SUBJECT?: Only a small number of adolescents with suicidal behaviour receives any follow-up treatment. The implementation of recurrent behaviour prevention strategies is crucial in the period following suicide attempts and should take into account adolescents' opinions to be effective and congruent. WHAT DOES THIS PAPER ADD TO EXISTING KNOWLEDGE?: This paper shows that the 33 adolescent participants in the study identified the following protective factors of recurrent suicidal behaviour: family, friends and other trusted persons, as well as the self and newly learned strategies. The adolescents described their family as a constant presence and reported wishing that their parents maintain their current family support. Psychological support, health professionals and occupational activities are what the adolescents value most about hospitalization, and some criticisms are related to the environment, activities and health professionals. The adolescents also emphasize the need to maintain contact with the nurses after hospital discharge and make suggestions for service improvement related to the environment and the interventions implemented. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Knowing the protective factors of recurrent suicidal behaviours, perception of the impact of the intervention, the expectation of future support and healthcare follow-up is crucial for adapting suicide prevention strategies to be put in place by health services for better quality care delivery. The results obtained allow us to define as specific implications the implementation of psychoeducational intervention directed at the adolescent's family with suicidal behaviour during hospitalization and the definition of strategies for maintaining contact and follow-up with the adolescent after discharge. This study emphasizes the need to reinforce training in suicidology for all health professionals for the improvement of clinical practice. ABSTRACT: INTRODUCTION: The prevention of recurrent suicidal behaviours in adolescents should consider their perceptions, needs and expectations. AIM/QUESTION: To identify the protective factors of recurrent suicidal behaviours in adolescents; To describe the family and the expectations for future involvement; To know the most important aspects of hospitalization and discuss expectations of nursing care follow-up after hospital discharge. METHOD: A descriptive, qualitative and exploratory study was carried out in a sample of 33 adolescents with suicidal behaviours. Data were collected through semi-structured interviews, and the data processing used the content analysis technique. RESULTS: Findings arising from data allowed identifying the protective factors: family, friends and other trusted persons. During the hospitalization, the adolescents reinforce the knowledge about themselves and the newly learnt coping strategies. Psychological support and health professionals are what they value most about hospitalization and emphasize the need to maintain contact with the nurses after discharge. DISCUSSION: Knowing the needs and expectations of adolescents with suicidal behaviour will make nursing psychotherapeutic interventions more effective and congruent in this vulnerable group. IMPLICATIONS FOR PRACTICE: Ensuring psychoeducational intervention to the families of adolescents with suicidal behaviour and continuity of care after discharge, and reinforcing the training in suicidology for all health professionals.

Characterization of adopted suicidal behavior and its main influencing factors: A qualitative study with adolescents.

INTRODUCTION: A better understanding of the meanings that adolescents associate with suicide, contributes to the development of psychotherapeutic intervention programs to be implemented by nurse specialists in mental health and psychiatric nursing. Therefore, adolescents need to characterize their adopted suicidal behaviors and identify the personal characteristics that contribute to this same behavior. METHODOLOGY: A descriptive, exploratory, and qualitative study was conducted with 33 adolescents with suicidal behavior, hospitalized in a child psychiatry unit. Data were collected through a structured interview, and data treatment used the content analysis technique. RESULTS: Suicidal behaviors are characterized according to causality, meaning, and intent. Causality is mostly related to psychological factors (sadness, desperation, mental suffering, internal pain, emptiness, and rejection). As to the meaning, suicidal behavior is understood as an escape but also as a personal choice, sometimes regarded as rational. In what concerns intent, the intent to die is the most frequently reported. The most-reported personal characteristics which contributed to the suicidal behavior are feelings of exclusion, rejection, and humiliation, and also introversion. CONCLUSIONS: The results point to the need to reflect on the perceptions of adolescents with suicidal behavior. The current intervention strategies should be adjusted especially through the identification of the signs associated with mental distress in adolescents and the training of gatekeepers, contributing to productive and congruent suicide prevention in this vulnerable group.

Development and dosimetry of 203Pb/212Pb-labelled PSMA ligands: bringing "the lead" into PSMA-targeted alpha therapy?

PURPOSE: The aims of this study were to develop a prostate-specific membrane antigen (PSMA) ligand for labelling with different radioisotopes of lead and to obtain an approximation of the dosimetry of a simulated 212Pb-based alpha therapy using its 203Pb imaging analogue. METHODS: Four novel Glu-urea-based ligands containing the chelators p-SCN-Bn-TCMC or DO3AM were synthesized. Affinity and PSMA-specific internalization were studied in C4-2 cells, and biodistribution in C4-2 tumour-bearing mice. The most promising compound, 203Pb-CA012, was transferred to clinical use. Two patients underwent planar scintigraphy scans at 0.4, 4, 18, 28 and 42 h after injection, together with urine and blood sampling. The time-activity curves of source organs were extrapolated from 203Pb to 212Pb and the calculated residence times of 212Pb were forwarded to its unstable daughter nuclides. QDOSE and OLINDA were used for dosimetry calculations. RESULTS: In vitro, all ligands showed low nanomolar binding affinities for PSMA. CA09 and CA012 additionally showed specific ligand-induced internalization of 27.4 ± 2.4 and 15.6 ± 2.1 %ID/106 cells, respectively. The 203Pb-labelled PSMA ligands were stable in serum for 72 h. In vivo, CA012 showed higher specific uptake in tumours than in other organs, and particularly showed rapid kidney clearance from 5.1 ± 2.5%ID/g at 1 h after injection to 0.9 ± 0.1%ID/g at 24 h. In patients, the estimated effective dose from 250-300 MBq of diagnostic 203Pb-CA012 was 6-7 mSv. Assuming instant decay of daughter nuclides, the equivalent doses projected from a therapeutic activity of 100 MBq of 212Pb-CA012 were 0.6 SvRBE5 to the red marrow, 4.3 SvRBE5 to the salivary glands, 4.9 SvRBE5 to the kidneys, 0.7 SvRBE5 to the liver and 0.2 SvRBE5 to other organs; representative tumour lesions averaged 13.2 SvRBE5 (where RBE5 is relative biological effectiveness factor 5). Compared to clinical experience with 213Bi-PSMA-617 and 225Ac-PSMA-617, the projected maximum tolerable dose was about 150 MBq per cycle. CONCLUSION: 212Pb-CA012 is a promising candidate for PSMA-targeted alpha therapy of prostate cancer. The dosimetry estimate for radiopharmaceuticals decaying with the release of unstable daughter nuclides has some inherent limitations, thus clinical translation should be done cautiously.

The meaning of suicidal behaviour from the perspective of senior nursing undergraduate students.

The meaning ascribed to suicidal behaviours may influence the quality of the care provided to people at risk of suicide. Such a phenomenon has yet to be properly investigated amongst nursing undergraduate students, the aim of this study being to gain an understanding of the meanings of suicidal behaviour for a particular group of nurses. The study, which utilized grounded theory, was conducted in Brazil in 2016-2017 with 30 undergraduate students. The findings indicated that suicidal behaviour, classified according to the individual beliefs and judgements of the participants, presented a significant barrier to the delivery of care and was complex and multifaceted care phenomenon. Participants were often reluctant to discuss the topic, seemingly wanting to distance themselves from the care of persons exhibiting suicidal behaviour, and to avoid professional engagements relating to suicide prevention. Significant work is required in raising both an awareness and knowledge of suicidal behaviour befitting the promotion of tolerance, emotional competency, resilience, and empathy amongst nursing students.

Mental health literacy about schizophrenia: a survey of Portuguese youth.

AIM: Mental health literacy about psychotic disorders, specifically schizophrenia, may assist in appropriate help seeking and early intervention, preventing the exacerbation of symptoms and improving health outcomes in the medium and long term. The aim of this study was to characterize the level of mental health literacy of Portuguese youth concerning schizophrenia. METHODS: A mental health literacy questionnaire was administered to a random sample of Portuguese youth aged 14-24 years. This questionnaire evaluated the following components: recognition of disorders, knowledge about professionals and treatments available, knowledge about the effectiveness of self-help strategies, knowledge and skills to support and provide first aid to others, and knowledge of how to prevent mental disorders. RESULTS: There were 4938 adolescents and young adults who participated in the study. Schizophrenia or psychosis was recognized by 42.17% and 22.21%, respectively. Most young people recognized the potential helpfulness of family doctors, psychologists, psychiatrists and mental health services. There was also widespread belief in the potential helpfulness of family and friends, and lifestyle changes. However, teachers were not generally seen as a source of help. Appropriate mental health first-aid strategies were commonly endorsed, but there was a reluctance to ask about suicidal feelings and many endorsed speaking to the person firmly. Lifestyle factors were also commonly believed to be preventative. CONCLUSIONS: Although many Portuguese youth have beliefs that may assist early intervention, there was a substantial minority who did not. Given the central role of teachers in the lives of young people, it is notable that they were not seen as a potential source of help. Mental health first-aid skills of young people also need improvement.

A recombinant multiepitope protein for hepatitis B diagnosis.

Hepatitis B is a liver inflammation caused by hepatitis B virus (HBV) and can be diagnosed in clinical stage by hepatitis B core antibody from IgM class (anti-HBcIgM). Hepatitis B core antibody from IgG class (Anti-HBcIgG) appears quickly after IgM, reaching high titers in chronic hepatitis, and remains even after cure. Since hepatitis B core antibody (anti-HBc) is the first antibody identified and sometimes the only marker detected during the course of infection, it can be used both to indicate HBV acute infection (anti-HBc-IgM) and to identify individuals who have come into contact with the virus (anti-HBc-IgG). In this work we propose a recombinant hepatitis B core multiepitope antigen (rMEHB) to be used for diagnosis of hepatitis B. For this purpose, a synthetic gene coding for rMEHB was designed and cloned into vector pET21a with a 6xHis tag at the C-terminal. Time course induction in E. coli showed an induced protein with an apparent molecular mass of ~21 kDa. Protein purification was performed by a single step with affinity chromatography Ni-NTA. Circular dichroism spectroscopy indicated rMEHB as a thermal stable protein at pH 7.0 and 8.0. In these conditions rMEHB was successfully used to perform an enzyme linked immuno sorbent assay (ELISA) with positive and negative sera.

Occlusion of dentin tubules by desensitizing agents.

PURPOSE: To evaluate the occluding effect of five desensitizing agents on human dentin tubules. METHODS: 30 buccal and lingual surfaces were prepared from 15 extracted intact third molars. Each surface was polished with aluminum oxide abrasive papers to remove enamel and to expose the underlying dentin in cervical area. The flat dentin surfaces were treated with 0.5 M EDTA for 2 minutes to expose dentin tubule orifices. The samples were randomly divided into six groups: AS - immersed in artificial saliva at 37 degrees C for 2 weeks (control); OX - Oxagel (monopotassium oxalate), DU - Duraphat (sodium fluoride), DE - Desensibilize (strontium chloride), OD - Odahcam (acidulated phosphate fluoride) and SE - Sensodyne (strontium chloride + calcium carbonate abrasive). Dentin desensitizers were applied during 2 weeks and after each application the samples were kept in artificial saliva at 37 degrees C. The samples were prepared according to the scanning electron microscope procedures and were examined at x2000 magnification. RESULTS: The results were expressed in percent (%) of tubule occlusion and analyzed by ANOVA and Duncan's multiple range test (P < 0.05): AS- 45.41 +/- 11.65a; OX- 42.65 +/- 11.79a; DU- 47.25 +/- 8.59ab; DE- 49.36 +/- 18.27ab; OD- 64.43 +/- 15.55b and SE- 65.44 +/- 10.93b. Results suggest that the dentin surfaces treated with OD and SE showed higher tubule occlusion when compared to AS and OX, but were not different compared to DU and DE treatments.