Hydrochars produced with by-products from the sucroenergetic industry: a study of extractor solutions on nutrient and organic carbon release

Hydrothermal carbonization transforms biomass into value-added material called hydrochar. The release of nutrients (P, N, Ca, Mg, and K) and organic carbon (TOC) from hydrochar in different extractive solutions was investigated in this study. Two sets of hydrochar were produced: (i) hydrochar prepared from sugarcane bagasse and vinasse mixture (BV-HC) and (ii) hydrochar prepared by the addition of H₃PO₄ to this mixture (BVA-HC). Both hydrochar types released significative amounts of nutrient and organic carbon, mainly Ca (5.0 mg g^-1) in the mixture (KCl, K₂SO₄, NaOH, 1:1:1) extractive solution and TOC (72.6 mg g^-1) in the NaOH extractive solution, for BV-HC. Nutrient release was influenced by pH and ionic strength. The release of P, Ca, and Mg was affected by the presence of insoluble phosphate phases in BVA-HC. The release of nutrients P, N, Ca, Mg, and K and organic carbon demonstrated that hydrochar has potential for soil application purposes.

Alterations of cytochrome P450 and the occurrence of persistent organic pollutants in tilapia caged in the reservoirs of the Iguaçu River

Environmental chemicals originating from human activities, such as persistent organic pollutants (POPs), may interfere with the endocrine system of aquatic organisms. The effect of these chemicals on biota and human populations is of high public concern but remains poorly understood, especially in aquatic environments of South America. The aim of this study was to investigate the bioavailability of POPs and the related effects in caged male tilapia (Oreochromis niloticus) in four cascading reservoirs of the Iguaçu River, Southern Brazil. POPs including organochlorine pesticides (OCPs), polychlorinated biphenyl (PCBs), and polybrominated diphenyl ethers (PBDEs) were determined in the reservoir water and tissue samples of tilapia after two months of exposure. The PCB levels in water (14.7 ng L^-1) were 14 times higher than the limits permitted by the Brazilian legislation in the Salto Santiago (SS) reservoir. Similarly, concentrations of aldrin and its metabolites (6.05 ng L^-1) detected in the water sample of the Salto Osório (SO) reservoir were also above the permitted limits. RT-qPCR analysis revealed different transcript levels of cytochrome P450 enzymes (CYP1A and CYP3A) in the liver among the four groups, with induced activity in tilapia from the SS reservoir. Quantification of the CYP3A mRNA expression and catalytic activity showed higher values for fish caged at the SS reservoir. The fish from this site also had a higher number of eosinophils observed in the testes. Although overt measurements of endocrine disruption were not observed in caged fish, alteration of CYP enzymes with co-occurrence of organochlorine contaminants in water may suggest bioavailability of contaminants from agricultural sources to biota. Additional studies with feral or caged animals for a longer duration may be necessary to evaluate the risks of the waterways to humans and wildlife.

The influence of ultrasound on the retention of cast posts cemented with different agents

AIM

The aim of this study was to evaluate the influence of ultrasound during the removal of posts cemented with either zinc phosphate cement, glass ionomer cement or resin cement.

METHODOLOGY

Eighty-four single-rooted teeth were prepared and after cementation of cast posts, they were randomly divided into six groups of 14. Group 1, 2 and 3 did not receive ultrasonic vibration, whilst groups 4, 5 and 6 received ultrasonic vibration for 10 min. The force necessary for post removal was determined using a universal testing machine. Results were statistically analysed using ANOVA and Tukey tests (5%).

RESULTS

The application of ultrasonic vibration reduced the retention provided by zinc phosphate and glass ionomer cements by 39% and 33%, respectively.

CONCLUSIONS

A statistically significant reduction in the force necessary to remove posts cemented with zinc phosphate and glass ionomer cements occurred following application of ultrasound. The application of ultrasonic vibration did not influence the retention of cast posts cemented with resin cement.

Cytologic diagnosis of vaginal metastasis from renal cell carcinoma. A case report

BACKGROUND

Metastasis of renal cell carcinoma to the vagina is rare, although it may be the first evidence of the existence of the primary tumor.

CASE

A metastatic deposit of renal cell carcinoma in the vagina was diagnosed by cytology as clear cell adenocarcinoma, which was confirmed by biopsy. Radiographic and ultrasound examinations confirmed the renal site of origin, which was corroborated by immunohistochemistry of the biopsy specimen.

CONCLUSION

When a cytologic diagnosis of vaginal clear cell adenocarcinoma is made, metastasis of renal cell carcinoma should be considered in the differential diagnosis.

[Impact of environmental changes on sand fly ecology in southern Brazil]

Tree felling around a chicken coop and periodic insecticide spraying at the Palmital farm in the county of Terra Boa in southern Brazil impacted the ecology of sand fly species. The most prevalent species (51.6%) before clearing the trees and insecticide spraying was Lutzomyia migonei (França, 1920), and it is now Lutzomyia (Nyssomyia) whitmani (Antunes & Coutinho, 1939) (89.8%). There was a highly significant difference between the proportions of L. whitmani reported by this paper (89.8%) and another publication before the tree felling and insecticide spraying (32,6%).

[Comparison of the methods of cytobrush and Ayre spatula in the concentration of endocervical cells]

A comparison between two sampling methods of cervicovaginal material--cytobrush and Ayre's spatula--was performed to verify the endocervical cell concentration in a group of 163 asymptomatic women. Age ranged from 18 to 57 years, with an average of 30. Smears of both methods showed satisfactory cellularity for study. Cytobrush showed endocervical cells (columnar and/or metaplastic) in 100 cases (61.3%) and Ayre's spatula in 39 (20.2%). Cytobrush showed more efficient results in terms of endocervical cell concentration; according to literature, this can be an important factor in the sensitivity of the cytologic method to detect intraepithelial neoplasia.

Detection of Chlamydia trachomatis cervical infection: a comparison of Papanicolaou and immunofluorescent staining in smears obtained by Ayre's spatula and cytobrush

Two methods of staining (Papanicolaou versus direct immunofluorescence) and two methods of collection of the samples (Ayre's wooden spatula versus cervical Cytobrush) were compared in order to verify the efficiency in detecting Chlamydia trachomatis (CT) infections in the female genital tract. Out of 166 asymptomatic patients, 59 were positive for CT by means of direct immunofluorescence: 36 were detected in Cytobrush samples, 16 in Ayre's spatula samples, and 7 in the samples collected by both methods. Papanicolaou smears showed "moth-eaten" features suggestive of CT infection in a great number of metaplastic cells present in 35 cases: 24 collected by Cytobrush, 4 by Ayre's spatula and 7 by both methods. Our data show that Cytobrush is more efficient that Ayre's spatula in concentrating cellular material. It is thus possible to detect CT infection with more accuracy by means of direct immunofluorescence, and to suspect CT infection in smears collected by means of Cytobrush and stained by Papanicolaou's method.

Chlamydia trachomatis in cervical uterine irradiated cancer patients

Twenty-two women with uterine carcinoma with morphological alterations postradiation treatment suggestive of Chlamydia trachomatis infection were analyzed by direct immunofluorescence. The diagnosis was confirmed in 12 (54.4%) cases. Discussions of the presence of Chlamydia in irradiated cells were not found in the literature. This finding may signify a posttherapeutic morbidity or a preradiation infection.

[Chlamydia trachomatis in smears of irradiated uterine cervix: cytologic and immunocytochemical aspects]

Some authors recently suggested the role of Chlamydia trachomatis as a potentiating agent of female genital tract neoplasias. Cervicovaginal smears of women with uterine carcinoma treated with radiotherapy are analyzed in the present work. A series of such smears showed morphological changes suggestive of Chlamydia infection with the Papanicolaou stain. Confirmation of the presence of such agent was done using an avidin-biotin-peroxidase technique. A higher prevalence of Chlamydia in the group of patients with carcinoma of the uterus treated with irradiation than in the population without ionizing treatment was verified. The presence of cells with radiotherapic changes infected by Chlamydia is a new finding in cytology.