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The development of new wound dressings made from biomaterials, which offer a better cost-benefit ratio and accelerate the healing process, is increasing nowadays. Various biopolymers can be electrospun to form functional membranes for wound healing. Therefore, in this study, chitosan and nanochitosan membranes with or without hyaluronic acid were prepared using the electrospinning technique, characterized and evaluated in the healing of skin wounds in rats. Chitosan and nanochitosan solutions, with or without hyaluronic acid, were prepared at concentrations of 1%-4% using PEO (polyethylene oxide) and subjected to the electrospinning process to obtain membranes characterized by scanning electron microscopy (SEM), mechanical tests, and antimicrobial activity. The healing effect of the membranes was evaluated by monitoring the area of the lesions, contraction of the wounds, histologic analysis, and induction of pro-inflammatory cytokine (IL-1 α and TNF-α) production in rats. The nanochitosan and nanochitosan membranes with hyaluronic acid achieved greater fiber diameter and uniformity, resistance, elasticity, and thermal stability, in addition to good adhesion to the wound bed and permeation capacity. Despite not presenting antimicrobial activity in vitro, they contributed to the production of pro-inflammatory interleukins in the animals tested, provided physical protection, reduced the wound area more markedly until the seventh day of the evaluation, with an acceleration of the healing process and especially when functionalized with hyaluronic acid. These results indicate that the membranes may be promising for accelerating the healing process of chronic wounds in humans., (© 2024 Wiley Periodicals LLC.)

This work aimed to evaluate the effect of niobium addition on nickel-based catalysts and their performance in dry reforming reactions to produce syngas (H 2 and CO). Different quantities of Nb 2 O 5 (5, 10, and 20% w/w) were used to prepare the catalysts, while a fixed content of Ni was applied (20%). The catalysts were supported on MCM-41. Physical, chemical, and morphological analyses were conducted to assess the characteristics of the materials. The produced Nb-Ni catalysts were applied in dry reforming reactions at 800 °C for 12 h. The dry reforming results indicated that the catalyst with 10% Nb-Ni demonstrated the best conversion of CH 4 and CO 2 (> 97%) and a significant H 2 production (40%), with good stability during 12 h of reaction, while the catalyst with 5% Nb-Ni showed lower conversions and did not present good stability during the reaction. The catalyst with 5% Nb-Ni exhibited the highest production of H 2 (44%), and the lowest of CO (50.87%), probably due to the presence of parallel reactions that increased H 2 content and caused carbon (coke) formation. The characterization results of this material revealed the greatest formation of carbon on its surface. The presence of coke can prejudice the efficiency of the catalyst during a reaction and significantly reduce its lifetime. The catalyst with 10% Nb-Ni did not present coke formation, while the catalyst with 20% Nb-Ni showed carbon presence. The good dispersion of Ni on supports (Nb 2 O 5 and SiO 2 /MCM-41) can explain the best behavior of 10% Nb-Ni for dry reforming reactions. X-ray diffractometry of the solids suggests the contribution of both metals (Ni and Nb) to the reforming process. From the obtained results, the catalyst with 10% Nb-Ni was indicated as the most favorable for dry reforming reactions among the studied materials, displaying good stability and conversion along with resistance to carbon formation., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Brazil is one of the countries most affected by COVID-19, with the highest number of deaths recorded. Brazilian Health Institutions have reported four main peaks of positive COVID-19 cases. The last two waves were characterized by the emergence of the VOC Omicron and its sublineages. This study aimed to conduct a retrospective surveillance study illustrating the emergence, dissemination, and diversification of the VOC Omicron in 15 regional health units (RHUs) in MG, the second most populous state in Brazil, by combining epidemiological and genomic data. A total of 5643 confirmed positive COVID-19 samples were genotyped using the panels TaqMan SARS-CoV-2 Mutation and 4Plex SC2/VOC Bio-Manguinhos to define mutations classifying the BA.1, BA.2, BA.4, and BA.5 sublineages. While sublineages BA.1 and BA.2 were more prevalent during the third wave, BA.4 and BA.5 dominated the fourth wave in the state. Epidemiological and viral genome data suggest that age and vaccination with booster doses were the main factors related to clinical outcomes, reducing the number of deaths, irrespective of the Omicron sublineages. Complete genome sequencing of 253 positive samples confirmed the circulation of the BA.1, BA.2, BA.4, and BA.5 subvariants, and phylogenomic analysis demonstrated that the VOC Omicron was introduced through multiple international events, followed by transmission within the state of MG. In addition to the four subvariants, other lineages have been identified at low frequency, including BQ.1.1 and XAG. This integrative study reinforces that the evolution of Omicron sublineages was the most significant factor driving the highest peaks of positive COVID-19 cases without an increase in more severe cases, prevented by vaccination boosters.

Upgrading biogas to biomethane is of great interest to change the energy matrix by feeding the renewable fuel produced from biomass waste into natural gas grids or directly using it to replace fossil fuels. The study aimed to assess the adsorption equilibrium of CH 4 , CO 2, and H 2 O on a coconut-shell activated carbon (CAC 8X30) to provide data for further studies on its efficiency in upgrading biogas by Pressure Swing Adsorption (PSA). The adsorbent was characterized, and equilibrium parameters were estimated from monocomponent CH 4 , CO 2, and H 2 O equilibrium isotherms. Binary and ternary equilibrium isotherms were simulated, and the selectivity and adsorption capacity of the CAC 8X30 were calculated in dry and wet conditions and then compared with zeolite 13X as a reference material. Regarding characterization, Nitrogen and Hydrogen Physisorption results indicated that 94 % of the pore volume is concentrated in the region of micropores. The adsorption affinity with CAC 8X30 estimated from monocomponent isotherms was in the order K H20 > K CO2 > K CH4 . IAST-Langmuir model simulations presented good agreement with experimental binary equilibrium data. Further simulations indicated equilibrium selectivity for CO 2 over CH 4 (e.g., 4.7 at 1 bar and 298 K for a mixture of CH 4 /CO 2 , 60/40 vol%), which increased in the presence of moisture, indicating its suitability for upgrading humid biogas. Simulations for zeolite 13X suggested that the material is unsuitable in the presence of water vapor but presents higher selectivity than the CAC 8X30 in dry conditions. Hence, the integration of both materials might be helpful for biogas upgrading., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Ltd.)

This systematic review presents the potential of using feather waste as a β-keratin source, including the Brazilian scenario in the generation of this byproduct. The structure and properties of α- and β-keratin, the methods commonly reported to extract keratin from poultry feathers, and applications of feather keratin-based materials are also covered in this review. The literature search for poultry production data in Brazil was conducted for the last 2 years, for the period 2021-2022. A broad literature search for extraction methods and applications of feather keratin was done for the period 2001-2022. The poultry industry is one of the largest sectors of the food industry, and Brazil was the third-largest world producer of chicken meat with more than six billion chickens slaughtered in 2021. Poultry feathers constitute about 7% weight of broilers; thus, it can be estimated that about one million tons of poultry feathers were generated in Brazil in 2021, and the improper disposal of this byproduct contributes to environmental problems and disease transmission. The most common method of reusing feathers is the production of feather meal. From economic and environmental points of view, it is advantageous to develop processes to add value to this byproduct, including the extraction of keratin. Among natural biodegradable polymers, keratin-based materials have revolutionized the field of biomaterials due to their biocompatibility and biodegradability, allowing their application in biomedical, pharmaceutical, chemical, and engineering areas., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The present study described three synthesis routes using different natural polysaccharides as low-cost non-toxic fuels and complexing agents for obtaining MgO. Cassava starch, Aloe vera leaves (mainly acemannan) gel, and citric pectin powder were mixed with magnesium nitrate salt and calcined at 750 °C for 2 h. The samples were named according to the polysaccharide: cassava starch (MgO-St), citrus pectin (MgO-CP), and Aloe vera (MgO-Av). X-ray diffraction identified the formation of a monophasic periclase structure (FCC type) for the three samples. The N 2 adsorption/desorption isotherms (B.E.T. method) showed an important difference in textural properties, with a higher pore volume (V max = 89.76 cc/g) and higher surface area (SA = 43.93 m 2 /g) obtained for MgO-St, followed by MgO-CP (V max = 11.01 cc/g; SA = 7.01 m 2 /g) and MgO-Av (V max = 6.44 cc/g; SA = 6.63 m 2 /g). These data were consistent with the porous appearance observed in SEM images. Porous solids are interesting as adsorbents for removing metallic and molecular ions from wastewater. The removal of copper ions from water was evaluated, and the experimental data at equilibrium were adjusted according to the Freundlich, Langmuir, and Temkin isotherms. According to the Langmuir model, the maximum adsorption capacity (q max ) was 6331.117, 5831.244, and 6726.623 mg·g -1 for the adsorbents MgO-St, MgO-Av, and MgO-CP, respectively. The results of the adsorption isotherms indicated that the synthesized magnesium oxides could be used to decrease the amount of Cu 2+ ions in wastewater.

Since its first identification in Brazil, the variant of concern (VOC) Gamma has been associated with increased infection and transmission rates, hospitalizations, and deaths. Minas Gerais (MG), the second-largest populated Brazilian state with more than 20 million inhabitants, observed a peak of cases and deaths in March-April 2021. We conducted a surveillance study in 1240 COVID-19-positive samples from 305 municipalities distributed across MG's 28 Regional Health Units (RHU) between 1 March to 27 April 2021. The most common variant was the VOC Gamma (71.2%), followed by the variant of interest (VOI) zeta (12.4%) and VOC alpha (9.6%). Although the predominance of Gamma was found in most of the RHUs, clusters of Zeta and Alpha variants were observed. One Alpha-clustered RHU has a history of high human mobility from countries with Alpha predominance. Other less frequent lineages, such as P.4, P.5, and P.7, were also identified. With our genomic characterization approach, we estimated the introduction of Gamma on 7 January 2021, at RHU Belo Horizonte. Differences in mortality between the Zeta, Gamma and Alpha variants were not observed. We reinforce the importance of vaccination programs to prevent severe cases and deaths during transmission peaks.

In early 2020, one of the most prevalent symptoms of SARS-CoV-2 infection was the loss of smell (anosmia), found in 60-70% of all cases. Anosmia used to occur early, concomitantly with other symptoms, and often persisted after recovery for an extended period, sometimes for months. In addition to smell disturbance, COVID-19 has also been associated with loss of taste (ageusia). The latest research suggests that SARS-CoV-2 could spread from the respiratory system to the brain through receptors in sustentacular cells localized to the olfactory epithelium. The virus invades human cells via the obligatory receptor, angiotensin-converting enzyme II (ACE2), and a priming protease, TMPRSS2, facilitating viral penetration. There is an abundant expression of both ACE2 and TMPRSS2 in sustentacular cells. In this study, we evaluated 102 COVID-19 hospitalized patients, of which 17.60% presented anosmia and 9.80% ageusia. ACE1 , ACE2 , and TMPRSS2 gene expression levels in nasopharyngeal tissue were obtained by RT-qPCR and measured using ΔCT analysis. ACE1 Alu 287bp association was also evaluated. Logistic regression models were generated to estimate the effects of variables on ageusia and anosmia Association of ACE2 expression levels with ageusia. was observed (OR: 1.35; 95% CI: 1.098-1.775); however, no association was observed between TMPRSS2 and ACE1 expression levels and ageusia. No association was observed among the three genes and anosmia, and the Alu 287bp polymorphism was not associated with any of the outcomes. Lastly, we discuss whetherthere is a bridge linking these initial symptoms, including molecular factors, to long-term COVID-19 health consequences such as cognitive dysfunctions., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Braga-Paz, Ferreira de Araújo, Alves, de Ávila, Resende, Teixeira, de Aguiar, de Souza and Bahia.)

The emergence and global dissemination of Severe Acute Respiratory Syndrome virus 2 (SARS-CoV-2) variants of concern (VOCs) have been described as the main factor driving the Coronavirus Disease 2019 pandemic. In Brazil, the Gamma variant dominated the epidemiological scenario during the first period of 2021. Many Brazilian regions detected the Delta variant after its first description and documented its spread. To monitor the introduction and spread of VOC Delta, we performed Polymerase Chain Reaction (PCR) genotyping and genome sequencing in ten regional sentinel units from June to October 2021 in the State of Minas Gerais (MG). We documented the introduction and spread of Delta, comprising 70 per cent of the cases 8 weeks later. Comparing the viral loads of the Gamma and Delta dominance periods, we provide additional evidence that the latter is more transmissible. The spread and dominance of Delta did not culminate in the increase in cases and deaths, suggesting that the vaccination may have restrained the epidemic growth. Analysis of 224 novel Delta genomes revealed that Rio de Janeiro state was the primary source for disseminating this variant in the state of MG. We present the establishment of Delta, providing evidence of its enhanced transmissibility and showing that this variant shift did not aggravate the epidemiological scenario in a high immunity setting., (© The Author(s) 2022. Published by Oxford University Press.)

During the poultry industrialization process the so-called sludge oil, a residual chicken fat, is recovered in the wastewater treatment plant and its use presents potential as raw material for biodiesel production. Thus, the aim of the study was to prepare blends of sludge oil with soybean oil to obtain fatty acid methyl esters (FAME) through the homogeneous alkaline transesterification reaction. To perform this study, a simple pre-treatment process - heating and subsequent filtration - was used, allowing sludge oil to be mixed with soybean oil to compose blends, without the need to use more sophisticated pre-treatment processes. After this step, blends ranging from 5% to 90% (m/m) of sludge oil mixed with soybean oil were prepared. The results showed that the molar ratio (1:6 oil blend:methanol), catalyst concentration 0.5% NaOH (m cat /m oil ), at 65 °C for 60 min yielded FAME above 99.0 and 90.0% (m/m) for blends with up to 5 and 15% sludge oil, respectively. By increasing the temperature to 70 °C, under the same selected parameters, the blend with 10% sludge oil provided yield above 99.0% (m/m), presenting appropriate physicochemical properties, within the parameters required by National Agency of Petroleum, Natural Gas and Biofuels (ANP). These findings show the great potential sludge oil provides to reduce Brazil's dependency on soybean oil for biodiesel production. Highlights Sludge oil, a waste raw material for biodiesel production, is not yet explored in Brazil.A procedure for biodiesel production using soybean oil and sludge oil blends was proposed.The best reaction condition was 1:6 oil blend:MeOH molar ratio; 0.5% NaOH (m cat /m oil ), at 70 °C for 60 min.Biodiesel yield was higher than 99% (m/m) under optimal reaction conditions.Sludge oil represents a promising waste raw material for biodiesel production.

Background: The coronavirus disease 2019 (COVID-19) pandemic had quite an impact on dental health care. Concerns about the risk of SARS-CoV-2 transmission through contaminant fluids and droplet formation during several dental procedures highly impacted dental health care, drastically reducing the number of dental practices worldwide. To monitor SARS-CoV-2 contamination in dental clinics, a longitudinal study was carried out during the return of dental practice at university., Methods: Dental health care professionals [(DHCPs); teachers, undergraduate dental students, and dental assistants] and patients were screened for SARS-CoV-2 RNA in a dental school clinic environment from 11 th January to 12 th March 2021 (9 weeks). Serological testing was performed on DHCPs in two-time points. Additionally, samples with low Ct values were sequenced to identify the circulating SARS-CoV-2 variant and possible transmission clusters., Results: We found a low number of dental staff (5.8%), patients (0.9%), and environment sites (0.8%) positive for SARS-CoV-2. Most positive cases had asymptomatic to mild symptoms, and two asymptomatic DHCPs presented prolonged infection. In the first week after previous exposure to COVID-19, 16.2% of DHCPs had IgM or IgG antibodies against SARS-CoV-2, and 1/3 of them had undetected antibodies in the last weeks. The variant zeta (P.2) could be detected. No cross-infection was observed between participants., Conclusion: Our study suggests that dental practice can be safely executed when adequate control measures and biosafety protocols are applied. DHCP and patient testing, patient telemonitoring, proper use of personal protection equipment, and sanitization of surfaces are essential to avoid SARS-CoV-2 cross-infection in dental practice., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Miguita, Martins-Chaves, Geddes, Mendes, Costa, Fonseca, Menezes, Souza, Queiroz, Alves, Freitas, Cruz, Moreira, Moreira, Bemquerer, Aguilar, Souza e Silva, Sampaio, Jardilino, Souza, Silva, Gomes, de Abreu, Aguiar, Souza and Gomez.)

Silver nanoparticles (AgNPs) can be produced through an easy and safe process called green synthesis and have been considered an efficient antimicrobial agent. The antimicrobial effect of silver nanoparticles green synthesized with E. tirucalli (aveloz) can be a promising technique for preserving stored strawberries. The objective of this work was to perform a green synthesis of AgNPs with aveloz extract (Av) and evaluate its effect on the physiology and preservation of stored strawberries. Silver nitrate was reduced with Av to produce Av-AgNPs. The Av-AgNPs were characterized by Scanning Electron Microscope, Energy Dispersive X-ray Spectrometry, and laser diffraction. The in vitro antifungal activity of Av-AgNPs was evaluated against Botrytis cinerea and Rhizopus stolonifer . Strawberries were treated with Av-AgNPs and stored (5 °C) for 12 days. Respiratory rate, decay, fresh mass loss, firmness, total phenolics and antioxidant activity of the strawberries were evaluated. According to the results, Av-AgNPs synthesis was performed, and it presented sizes between 40 and 90 nm. Av-AgNPs inhibited B. cinerea but was less effective for R. stolonifer . Total phenolic compounds, antioxidant activity, fresh mass loss and firmness of strawberries were not influenced by Av-AgNPs. Treated strawberries had a lower respiratory rate than the control and showed no symptoms of microbiological deterioration until 9 days of storage, while in the control the deterioration symptoms started after 3 days. This study showed that the green synthesis of AgNPs with Av produced nanoparticles smaller than 100 nm, and that they were effective against strawberries decay during storage, indicating to be a promising protection technique against decay., Competing Interests: Conflicts of interestThe authors declare that they do not have any conflict of interest., (© Association of Food Scientists & Technologists (India) 2021.)

The COVID-19 pandemic has created an unprecedented need for epidemiological monitoring using diverse strategies. We conducted a project combining prevalence, seroprevalence, and genomic surveillance approaches to describe the initial pandemic stages in Betim City, Brazil. We collected 3239 subjects in a population-based age-, sex- and neighborhood-stratified, household, prospective; cross-sectional study divided into three surveys 21 days apart sampling the same geographical area. In the first survey, overall prevalence (participants positive in serological or molecular tests) reached 0.46% (90% CI 0.12-0.80%), followed by 2.69% (90% CI 1.88-3.49%) in the second survey and 6.67% (90% CI 5.42-7.92%) in the third. The underreporting reached 11, 19.6, and 20.4 times in each survey. We observed increased odds to test positive in females compared to males (OR 1.88 95% CI 1.25-2.82), while the single best predictor for positivity was ageusia/anosmia (OR 8.12, 95% CI 4.72-13.98). Thirty-five SARS-CoV-2 genomes were sequenced, of which 18 were classified as lineage B.1.1.28, while 17 were B.1.1.33. Multiple independent viral introductions were observed. Integration of multiple epidemiological strategies was able to adequately describe COVID-19 dispersion in the city. Presented results have helped local government authorities to guide pandemic management., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Silva, Menezes, Moreira, Torres, Fonseca, Moreira, Alves, Alves, Amaral, Coelho, Saraiva Duarte, da Rocha, de Almeida, de Araújo, de Oliveira, de Oliveira, Zolini, de Sousa, de Souza, de Souza, Ferreira, Lehmkuhl Gerber, Guimarães, Maia, Marim, Miguita, Monteiro, Neto, Pugêdo, Queiroz, Queiroz, Resende-Moreira, Santos, Souza, Voloch, Vasconcelos, de Aguiar and Souza.)

In this work, the reduction of the moisture content from waste oils by a bentonite-based adsorption process was investigated as an alternative for reuse in energy production. Waste cooking oil (WCO) and waste poultry fat (WPF) were characterised (moisture and viscosity, values of acidity, saponification, and peroxide), as well as bentonite clay adsorbent. The response surface methodology (RSM) was applied to define the best moisture adsorption condition by bentonite-based adsorbent regarding a full factorial experimental design (FFED). In the framework of RSM, the adsorbent mass, oil acidity, and agitation speed were varied in three levels in the range of 1.5-3.0 g, 1-38 mg KOH g oil -1 , and 50-150 rpm, respectively, while the adsorption time was fixed in 24 h. Under the best moisture adsorption condition, kinetic tests were performed in a 1-24 h contact time range, besides performing equilibrium adsorption tests at 5 h contact time. Around 90% moisture removal was attained with 1.5 g adsorbent, acidity value of 1 mg KOH g oil -1, and 50 rpm agitation speed, achieving the equilibrium in 5 h. A multilayer adsorption process, as described by the BET isotherm model, was acting in dried bentonite clay, allowing getting excellent moisture adsorption capacity (∼200 mg water g Bent -1 ). Therefore, moisture removal from waste oils by a bentonite clay-based adsorption process has provided results that are suitable and recommendable for economically viable biodiesel production.

ACE2 and TMPRSS2 are key players on SARS-CoV-2 entry into host cells. However, it is still unclear whether expression levels of these factors could reflect disease severity. Here, a case-control study was conducted with 213 SARS-CoV-2 positive individuals where cases were defined as COVID-19 patients with respiratory distress requiring oxygen support (N = 38) and controls were those with mild to moderate symptoms of the disease who did not need oxygen therapy along the entire clinical course (N = 175). ACE2 and TMPRSS2 mRNA levels were evaluated in nasopharyngeal swab samples by RT-qPCR and logistic regression analyzes were applied to estimate associations with respiratory outcomes. ACE2 and TMPRSS2 levels positively correlated with age, which was also strongly associated with respiratory distress. Increased nasopharyngeal ACE2 levels showed a protective effect against this outcome ( adj OR = 0.30; 95% CI 0.09-0.91), while TMPRSS2/ACE2 ratio was associated with risk ( adj OR = 4.28; 95% CI 1.36-13.48). On stepwise regression, TMPRSS2/ACE2 ratio outperformed ACE2 to model COVID-19 severity. When nasopharyngeal swabs were compared to bronchoalveolar lavages in an independent cohort of COVID-19 patients under mechanical ventilation, similar expression levels of these genes were observed. These data suggest nasopharyngeal TMPRSS2/ACE2 as a promising candidate for further prediction models on COVID-19.

The anaerobic digestion is a process widely recognized as an interesting alternative for the treatment and stabilization of residual organic substrates. However, several technical limitations were observed based on the characteristics of the organic matter submitted to the process, such as the presence of high concentrations of soluble sugars or fats. The technology of anaerobic digestion in multiple stages is described as a viable option in the control of variables, optimizing the environmental conditions of the main microorganisms involved in the process, assuring high solid removal and methane production, besides allowing a higher energy yield through the generation of molecular fuel hydrogen. Several studies reviewed the process of anaerobic digestion in multiple stages in the treatment of food waste, although few report its use applied directly to agroindustrial residues. Thus, the present work aims to review the literature evaluating the scenario and viability of the multi-stage anaerobic digestion process applied to agroindustrial effluents. Effluents such as manipueira, vinasse, and dairy wastewater are substrates that present high yields when treated by AD processes with stage separation. The high concentration of easily fermentable sugars results in a high production of molecular hydrogen (co-product of the production of volatile acids in the acid phase) and methane (methanogenic phase). The great challenges related to the development of the sector are focused on the stability of the composition and yield of hydrogen in the acid phase, besides the problems resulting from the treatment of complex residues. Thus, the present study suggests that future works should focus on the technologies of new microorganisms and optimization of process parameters, providing maturation and scale-up of the two-stage anaerobic digestion technique., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

This work describes the production/characterization of low molar mass chitosan nanoparticles derived from waste shrimp shells (SSC), as well as from a commercial chitosan (CC). The production of low molar mass nanochitosan employed thermal shock, alternating between 100 °C and ambient temperature, followed by grinding the dry material (SSC and CC) in a ball mill, producing around 500 g of nanochitosan per batch. A highlight of the methodology employed is that it enables nanochitosan to be obtained even from a low quality commercial raw material. All particles had diameters smaller than 223 nm, with an average diameter below 25 nm (determined by DLS), while reductions of molar mass were between 8.4-fold and 13.5-fold. The depolymerization process resulted in a reduction in crystallinity of 38.1 to 25.4% and 55.6 to 25.9% in the CC and SSC samples, respectively. The production of nanochitosans was also confirmed by TEM through the observation of crystalline domains with diameters between 5 and 10 nm. This work perfectly reproduces the results on bench scale from previous research. The simple and inexpensive processes enable easy scale-up, representing an important advance in the production chain of biopolymers. Graphical abstract.

Objectives: to systematize permanent participatory education experience with Primary Care nurses on breast and cervical cancer screening, identifying potentialities and vulnerabilities., Methods: systematic account according to Holliday, in five stages: starting point, initial questions, recovery of the lived process, background reflection and arrival points. It was the product of two workshops with 96 nurses and analyzed in the light of the ministerial guidelines and Ayres' concept of vulnerability., Results: the potentialities are related to the nurse's work implementing the principles of the Unified Health System. The difficulties are complex and expose individual, contextual and programmatic vulnerabilities in the practice of screening., Final Considerations: permanent education and participatory pedagogical strategies allowed a wide and playful exchange of learning and the participation of a significant number of professionals. There is a need for studies on the institutionality of programmatic guidelines and nurses' space to be the initiator of new practices within the scope of Primary Care.

Currently, there are several studies using calcium oxide, calcium alkoxide, and calcium hydroxide for biodiesel production. However, there is still a lack of studies highlighting the use of calcium diglyceroxide (calcium oxide enriched with glycerin in the presence of methanol) as a catalyst in the transesterification process. Therefore, the present work aimed to investigate the catalytic efficiency and reutilization of the eggshell calcined and enriched with glycerin and methanol (ECEG), in the synthesis of methylic esters from frying residual oil. As a result, thermochemically modified eggshells showed catalytic efficiency during methylic transesterification of residual oils in mass concentrations of 15%, 5%, 3%, and 1% due to the presence of a high level of esters (97.39, 96.97, 97.75, and 92.96%, respectively). The initial concentration of the enriched eggshell used in methanolysis had a direct effect on the final ester mixture. A 15% increase in the water content of the frying oil contributed to an increase in the ester content. The ECEG was reactive and efficient for four reaction cycles (without reactivation of the catalytic sites) due to the evidence of a high ester content (97.85%, 98.67%, 98.89%, 98.46%), reaching the standard quality of worldwide biodiesel regulations. Graphical abstract.

Several waste sources have been studied as substrate sources for the production of biogas rich in hydrogen and for the isolation of bacteria capable of fermenting several substrates for the same purpose. Nonetheless, to simplify the process and minimize production costs, it is important to seek alternatives both for the use of microbial consortia using crude waste and for the use of substrates also in their crude form, without the need for purification. The aim of this study was to use only waste as inoculum and substrate for the biological production of hydrogen. Thus, samples from anaerobic ponds of a poultry slaughterhouse were used as inoculum. Sucrose, pure glycerol (in initial tests) and crude glycerol (inserted in blends with pure glycerol) were used as substrates. H 2 production experiments were conducted in batches, using a reactor kept in an anaerobic environment for 11 days, at 35°C, under orbital agitation at 150 rpm. To analyse the composition of the biogas and the presence of soluble metabolic products (SMPs), samples of the headspace gases generated and of the reaction medium were collected. The results using sucrose as substrate indicated that the inoculum under study has potential for bio-H 2 production, as it produced CH 4 -free biogas containing 50-60% H 2 . The inoculum was also shown to be adaptable to the use of glycerine as a substrate, producing biogas with similar characteristics to those obtained from sucrose degradation; however, it required a longer acclimatization period, and thus more in-depth study is required., (Copyright © 2019 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Electrochemical techniques were used to investigate the behavior of lomustine (CCNU) and its degradation in aqueous solution at a glassy carbon electrode (GCE). The in situ interaction of CCNU and chemically degraded CCNU (cdCCNU) with dsDNA was then investigated in dsDNA incubated solutions, using dsDNA electrochemical biosensors and comet assays. CCNU undergoes electrochemical reduction in two irreversible, diffusion-controlled, and pH-dependent redox processes, each with transfer of two electrons and one proton. At pH ≥ 10.1, the peak potential for the two processes was essentially pH-independent and involved only one electron. A mechanism was proposed for the reduction of CCNU in a neutral medium. In addition, it was found that CCNU underwent spontaneous degradation during incubation in aqueous solution, without the formation of electroactive degradation products. The degradation process was faster in basic media. Moreover, this pro-drug interacted with the DNA. Its metabolite(s) initially caused condensation of the double helix chains, followed by the unwinding of these chains. In addition, free guanine (Gua) was released from the dsDNA and oxidative damage to the DNA by the CCNU metabolite(s) was evidenced from the detection of 8-oxoGua and 2,8-oxoAde. These results were confirmed by the poly(dA)- and poly(dG)-polyhomonucleotide biosensors, which revealed the oxidative damage caused to both bases (guanine and adenine) of the dsDNA by the CCNU metabolite(s). The comet assay indicated breaks in the single strand DNA, complementing the results of the studies using differential pulse voltammetry. Conformational changes of dsDNA caused by CCNU and cdCCNU were confirmed using comet assays., (Copyright © 2019 Elsevier B.V. All rights reserved.)

This work focused in the evaluation of Oreochromis niloticus fish scales (FS) as biosorbent material in the removal of Zn from a synthetic effluent based on automotive battery industry effluent and, further, a hybrid neutralization/biosorption process, aiming at a high-quality treated effluent, by a cooperative use of dolomite and FS. For this, a physicochemical and morphological characterization (i.e. SEM-EDX, FTIR, XRD, and TXRF) was performed, which helped to clarify a great heterogeneity of active sites (phosphate, carbonate, amide, and hydroxyl) on the biosorbent; also the inorganic constituents (apatites) leaching from the FS was identified. Biosorption results pointed out to a pH-dependent process due to changes in the functional group's anionic character (i.e. electrostatic interactions), where an initial pH = 3 favored the Zn uptake. Kinetic and equilibrium studies confirmed the heterogeneous surface and cooperative sorption, wherein experimental data were described by Generalized Elovich kinetic model and the favorable isotherm profile by Langmuir-Freundlich isotherm ( q m a x  = 15.38 mg g -1 and 1 / n > 1 ). Speciation diagram of Zn species along with the leached species demonstrated that, for the studied pH range, the biosorption was the most likely phenomena rather than precipitation. Finally, the hybrid neutralization/biosorption process showed great potential since both the Zn concentration levels and the pH reached the legislation standards ( C Zn  = 4 mg L -1 ; pH = 5). Hence, based on the characterization and biosorption results, a comprehensive evaluation of the involved mechanisms in such complex system helped to verify the prospective of FS biosorbent for the Zn treatment from solution, in both individual and hybrid processes.

This work aims to evaluate the adsorption potential of bentonite and sugarcane bagasse clay for the reduction of free fatty acids in cooking oil through batch technique, experimental planning with different operating conditions (temperature, adsorbent mass and agitation). After were carried out kinetic studies and thermodynamic studies. Thus, both adsorbents were characterized by nitrogen dispersion, scanning electron microscopy with coupled energy dispersion spectroscopy. The sugarcane bagasse provided higher reductions compared to the bentonite clay, 58 and 50%, respectively. In the kinetic studies, it was observed that the pseudo-secunda model for both materials. Among the isotherms studied, the Langmuir model was better adjusted for sugarcane bagasse and Freundlich for bentonite clay. Thermodynamic parameters indicated spontaneous and endothermic adsorption at temperatures of 18°C, 20°C and 25°C. Both materials showed an advantageous result with the reduction to the adsorption of free fatty acids in the residual oil, considering that they are low-cost materials, their pre-treatment is simple from the operational point of view and their physical and chemical characteristics are favorable to the adsorption process, sugarcane bagasse contains about 42% hemicellulose, which is a hydroxyl-rich material that attracts the H + ions from the medium.

Leishamaniasis is a neglected disease caused by over 20 Leishmania species, occurring in more than a hundred countries. Miltefosine (hexadecylphosphocholine) is the single oral drug used in treatment for leshmaniases, including cases of infections resistant to pentavalent antimony. Our group has recently demonstrated the ability of miltefosine to cause genomic lesions by DNA oxidation. Acknowledging that antioxidant compounds can potentially modulate Reactive Oxygen Species (ROS), our study verified whether ascorbic acid reduces the genotoxic and mutagenic effects caused by miltefosine, and whether it interferes with drug efficacy. For this purpose, uninfected Swiss mice received simultaneous (single dose treatment) miltefosine and ascorbic acid (gavage and intraperitoneally), besides pre and post treatments (ascorbic acid 24 h before and after drug administration); furthermore, Balb/c mice infected with Leishmania infantum received miltefosine plus ascorbic acid (repeated doses treatment). We conducted comet assays, micronucleus tests, dosages of superoxide dismutase enzyme and parasitic burden by the limiting dilution assay. We observed that ascorbic acid administered intraperitoneally displayed a protective effect over damage caused by miltefosine. However, this effect was not not observed when the same doses were administered via gavage, possibly due to low serum levels of this antioxidant. Ascorbic acid's protective effect reinforces that miltefosine damages DNA by oxidizing its nitrogenous bases, which is reduced by ascorbic acid due to its ability of protecting genetic material from the action of ROS. Therefore, our results show that this drug is efficient in reducing parasitic burden of L. infantum., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objective: This article describes the implementation and functioning of a telemonitoring center of neonatal intensive care units (NICUs) organized by the Telehealth Center of the Medical School of the Federal University of Minas Gerais who signed an agreement with the Minas Gerais State Department of Health (SES/MG, in Portuguese), Brazil., Study Design: This is a descriptive retrospective study from December 2012 to June 2014 of a NICU telemonitoring project., Results: Twelve Web conferences have been performed. Six thousand, eight hundred and thirty nine (6,839) online teleconsultations of pediatricians and nurses with experience in neonatology and intensive care have been performed, of which 174 were with subspecialists, with an average response time of 6 hours., Discussion: The project has demonstrated to be satisfactory, with fast response in relation to the demands of subspecialists, promoting care, and management support to the NICU. The qualification via Web conferences prevents the displacement of the professionals to big centers for continuous medical education., Conclusion: The telemonitoring of NICU can contribute in the process of management, regulation of beds, reduction of displacements and transferences, adhesion to best practices, care support, and qualification of the involved professionals., Competing Interests: None., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Since industrial wastes are increasing, the development of studies to find ways for their use is urgent. Waste cooking oil is an important source for the production of biodiesel, one of the main biofuels in Brazil. However, during cooking, the oil undergoes conditions that change its properties and decrease its quality, such as its acidity value. Current research treats waste cooking oil by the adsorption process using rice husk, an agro-industrial waste, and activated carbon to compare results. The potential of the adsorbents to remove free fatty acids in waste cooking oil has been investigated by the batch technique, evaluating different operating conditions of temperature, adsorbent mass and agitation. Adsorbents were characterized by nitrogen physisorption, scanning electron microscope, energy-dispersive spectroscopy and X-ray diffraction. The maximum result obtained for activated carbon at acidity reduction was 63%, using 22.4°C, 169.64 rpm and 3.39 g of adsorbent mass. Already, using the rice husk the percentage of removal was the same, 63% using 22.4°C, 80.36 rpm and 1.61 g of adsorbent, however in shorter times. The results prove that the application of the rice husk for this purpose is advantageous, for being a low-cost material, available on a large scale and that provide results similar to activated carbon.

Sugarcane vinasse is a by-product obtained during ethanol production in sugar-ethanol plants. For each 1 L of ethanol produced approximately 11 L of vinasse are generated. As this residue is obtained in high amounts, it is used as fertilizer in sugarcane crops. However, despite being rich in nutrients, sugarcane vinasse is approximately one hundred times more polluting than domestic sewage, making it an environmental problem. Thus, the aim of the present study was to propose a treatment sequence for sugarcane vinasse and evaluate the possibility of energetic use of the generated sludge in the coagulation/flocculation stage. pH, conductivity, turbidity and decreases in UV/Vis absorption spectra were determined for each treatment step. In addition, the upper calorific value of the generated sludge was also determined, while ash (adsorption treatment) and catalyst (heterogeneous photocatalysis) characterizations were also carried out. At the end of the treatment, initial vinasse turbidity was reduced by 100% and pH and conductivity values were stabilized. The sludge presented a higher calorific value of approximately 3,000 kcal kg -1 and the ash and catalyst displayed favorable characteristics to be applied to the sugarcane vinasse treatment stages.

Introduction: The Belo Horizonte Telehealth program, a pioneer in telemedicine within the Brazilian National Health System (Sistema Único de Sauùde in Portuguese), was implemented by the Belo Horizonte City Health Department (SMSA-BH) in 2004. The purpose of the present study is to analyze opinions on the obstacles, difficulties, and suggestions on the use of teleconsultations., Methods: Semi-structured interviews were conducted among primary healthcare professionals and health managers. Content analysis for the latter was carried out using NVIVO ® software to categorize responses. Simple descriptive quantitative aspects were analyzed to verify the use of the system over the years by the primary care unit (PCU) professionals., Results: The difficulties encountered were related to the use of the system, inadequate response to teleconsultation requests, infrastructure problems, lack of practicality for the use of the program, difficulty in incorporating the program into the organizational culture, and lack of managerial support. Changes in management organization over the years have interfered with the use of the teleconsultation system. The most requested specialties were neurology, cardiology, endocrinology, and angiology., Discussion: The main suggestions for increasing the number of teleconsultations requests included dissemination of information and prioritization by the management; improvement of the infrastructure; organization of the time and the agenda of the PCU professional; training the professionals for its use; and preconditioning the referrals to secondary level care to a previous teleconsultation., Conclusion: Teleconsultations need to be incorporated in the daily routine of PCUs by both managers and health professionals to assure its usage and improve the quality of care.

Intensive aquaculture needs to adopt techniques that are able to contribute towards sustainability. Closed systems that employ water recirculation can combine intensive production with environmental sustainability, since there is no exchange of water or discharge of effluents into the environment. In order to achieve this, effective filtration systems are required to ensure that the water quality is satisfactory for the cultivation of aquatic organisms. Chitosan, an industrial waste material derived from crustacean farming, is a renewable natural material that is biodegradable and possesses adsorbent characteristics. In this work, chitosan foam was incorporated in filters and was evaluated as an adsorbent of aquaculture pollutants, adding value to the material and at the same time providing a use for industrial waste. The foam was characterized by scanning electron microscopy and energy dispersive spectroscopy, apparent density, and water absorption capacity. It was used to remove ammonia, nitrite, orthophosphate, and turbidity from aquaculture effluents. The foam consisted of a bilayer with smooth and porous sides, which presented low density, flexibility, and high water absorption capacity. The best proportion of the foam, in terms of the mass of foam per volume of solution (% m v -1 ), was 0.10, which resulted in removal of 32.8, 57.2, 89.5, and 99.9% of ammonia, nitrite, orthophosphate, and turbidity, respectively. This biopolymer produced is biodegradable, and when saturated with organic compounds from aquaculture, and no longer suitable for reuse as a filter material, it can be employed as a fertilizer, hence closing the sustainability cycle of the aquaculture production chain.

Miltefosine was developed to treat skin cancer; further studies showed that the drug also has activity against Leishmania. Miltefosine is the first oral agent for treating leishmaniasis. However, its mechanism of action is not completely understood. We have evaluated the induction of DNA damage by miltefosine. Cytotoxicity and genotoxicity (comet assay) tests were performed on human leukocytes exposed to the drug in vitro. Apoptosis and necrosis were also evaluated. In vivo tests were conducted in Swiss male mice (Mus musculus) treated orally with miltefosine. Oxidation of DNA bases in peripheral blood cells was measured using the comet assay followed by digestion with formamidopyrimidine glycosylase (FPG), which removes oxidized guanine bases. The micronucleus test was performed on bone marrow erythrocytes. Miltefosine caused DNA damage, apoptosis, and necrosis in vitro. Mice treated with miltefosine showed an increase in the DNA damage score, which was further increased following FPG digestion. The micronucleus test was also positive., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The Brazilian aviation industry is currently developing biofuel technologies that can maintain the operational and energy demands of the sector, while reducing the dependence on fossil fuels (mainly kerosene) and greenhouse gas emissions. The aim of the current research was to identify the major environmental, economic and social impacts arising from the production of aviation biofuels in Brazil. Despite the great potential of these fuels, there is a significant need for improved routes of production and specifically for lower production costs of these materials. In addition, the productive chains of raw materials for obtaining these bioenergetics can be linked to environmental impacts by NOx emissions, extensive use of agricultural land, loss of wildlife and intensive water use, as well as economic, social and political impacts., (Copyright © 2015 Elsevier B.V. All rights reserved.)

In order to investigate the response of heart rate variability (HRV) components to postural change and their association with cardiovascular risk factors in shift workers, a cross-sectional study with 438 Brazilian males rotating shift workers was done. Anthropometric, body composition, and clinical measures were collected. Electrocardiogram was recorded for 3 minutes, in the supine and orthostatic position, and HRV components were extracted. Descriptive analyses showed that mean values of body mass index, waist circumference (WC), waist-to-height ratio, visceral fat area (VFA), and blood pressure (BP) were higher than the reference values. In the regression model, age, WC, VFA, and systolic BP showed negative association with HRV components. These findings suggest the need for determining effective strategies for the evaluation and promotion of health among shift workers focused on the altered variables.

Background: Telehealth activities are already going on in many Latin American countries. This article aims to present and evaluate a distance learning telehealth training course in the region., Materials and Methods: This was a cross-sectional descriptive study. A coordinating committee was formed, composed of medical school faculty from 15 countries, which defined the course's syllabus, teaching model, and mentoring structure. A questionnaire was prepared, using a Likert scale, in order to verify if the parameters of gender, age, professional category, postgraduate degree, and experience in distance education indicated any difference in relation to the course evaluation. The responses were analyzed by chi-squared test, considering as significant a value of p<0.05., Results: Of the 353 enrolled participants, 251 (71.10%) did the basic modules, and 96 (43.91%) completed the full training. In relation to the overall course assessment, it was considered excellent or good by 80.92% of participants, the mentors received positive evaluations by 72.83% of students, the course content was evaluated as excellent or good by 87.4% of students, and 94.40% of participants would recommend it. As for the parameters assessed, only experience in distance education was statistically significant for the evaluation of the tutors., Conclusions: The results presented indicate an important concern on the part of the Latin American countries participating on the course in relation to telehealth training activities. Regarding course assessment, high approval rates in relation to tutoring, educational model, course content, and goals were noted, corroborating literature data. The experience of conducting a Latin American shared telehealth training course was indeed positive, contributing to the development of telehealth actions.

This article aimed to systematize the views on telehealth in Latin America and to present the experience of building an instrument for monitoring the development of telehealth initiatives based on the reality of this region. A group was structured to coordinate telehealth efforts in Latin America, with members appointed by the ministries of health of 16 countries. Five thematic groups were also set up. Based on international experiences and focusing on the reality of telehealth in the continent, an instrument was created to monitor the development of telehealth in Latin America. Several countries have national telehealth projects: Brazil, Colombia, Ecuador, Mexico, Panama. Others are in the process of development and early deployment: Bolivia, Costa Rica, Cuba, El Salvador, Guatemala, Peru, Venezuela. The instrument described in the article, which is still being tested, proposes a characterization of countries according to their telehealth development stage: nonexistent, nascent, intermediate, advanced, and exemplary. Currently, important telehealth initiatives are already underway in Latin America.

Objective: The aim of this study is to report patient and physician profiles of those who used the teleconsultation system in the primary care health units of a health district in the city of Belo Horizonte, MG, Brazil., Materials and Methods: Data were collected from the telehealth attendance records of nine Primary Health Units (Unidade Básica de Saúde [UBS] in Portuguese) and from interviews carried out with the referring physicians. The criteria for inclusion required that data come from users seen by means of telehealth in the period between December 2004 and August 2010 and from the practitioners who saw them. The following were excluded: physicians who were not working in the UBS when the data were collected and a physician who did not agree to take part in the study., Results: Two hundred sixty-three teleconsultations were analyzed, and 20 referring physicians were interviewed. The offline method was the most common. The physicians were predominantly female and had graduated over 11 years ago. The patients were predominantly adult women. After teleconsultation, a prescription was not necessary for 9.8% of patients. When required, 83.2% of the medication was available in the UBS. In 68.3% of cases, additional tests were required. The incorporation of these technologies prevented the physical referral of patients in 64.2% of cases., Conclusions: Telehealth resources can help to improve the provision of primary healthcare, reducing the number of physically referred patients. The number of teleconsultations is still small, and there is a need to encourage physicians to use the system.

Introduction: The technological innovations that are a part of organizational realities allow for new possibilities in social processes. In Belo Horizonte, Brazil, the municipality established a system of training through videoconferences in primary care connecting professors and professionals from primary care units to discuss assistance problems in medicine, nursing, and dentistry., Objective: An evaluation of the professionals' perception regarding the system of training through videoconferences in primary care., Methods: The study involved 148 basic health units in the city of Belo Horizonte. A structured survey was applied to a sample of 373 people who used the system in 2008., Results: According to the survey data, 58.6% of the professionals participated in more than three videoconferences in 6 months, whereas 30.3% did not participate in any type of face-to-face training activity; 98% considered the topics interesting and 70% affirmed that the topics discussed helped them when performing assistance tasks. Other aspects that were evaluated as excellent or good include: 36.6% approved the sound quality of the videoconferences, 46.4% approved the image quality, and 43.9% approved the system stability. These results highlight some problems. Nevertheless, 90.2% evaluated the telehealth project as being excellent or good and 96.7% would recommend the implementation of the project in other units., Conclusions: The system of educational training videoconferences can contribute to improving the competence of primary healthcare attention.

Biphasic bioceramics have been widely indicated for bone reconstruction; however, the real gain in bone mass due to the presence of such biomaterials has not been established yet nor the advantages of its association with platelet concentrate. This study aims at quantifying the volume of bone matrix, osteoblasts, osteocytes, blood vessels and adipose tissue after the application of a biphasic bioceramics composed of 65% hydroxyapatite and 35% beta-tricalcium phosphate. Critical-size bone defects were produced in rabbit femora and reconstructed with bioceramics only, with bioceramics combined with platelet concentrate, with platelet concentrate alone, and with no treatment (blood clot). The quantitative evaluation was performed on histological sections using histomorphometry. Our data provide original evidence that consolidates the indication of bioceramics for clinical bone loss reconstruction. The application of biphasic bioceramics alone led to major bone mass gain and was followed by its association with platelet concentrate. On the other hand, platelet concentrate can contribute to the augmentation and maintenance of the adipose tissue, representing a new field for future applications in plastic surgery.

Objective: To qualitatively describe food practices of students living in a residence hall., Methods: A quantitative and qualitative study was carried out in a drawn sample of 100 university students living in a residence hall in the city of Campinas, Southeastern Brazil, in 2004. Students were interviewed using a questionnaire to collect 24-hour food recall information including open questions on shopping and intake practices. Criteria were established for the analysis of meal quality. The Chi-square and the exact Fisher test were used at a 5% significance level. Representations based on Moscivici's theory of social representations were obtained in the interviews and analyzed., Results: Assessment of 24-hour food recall: breakfast--30% of the students skipped it, 13% had full, 37% had standard and 20% had partial meal; lunch--5% skipped, 72% had full, and 23% had partial meal; dinner--1% skipped, 36% had full, and 63% had partial meal. Lunch was the best quality meal and of those who had lunch, 63% had it at the university cafeteria. Of all respondents, 48% had no fruit and 39% had no milk. Most (69%) showed an individual food behavior and 43% thought that having meals together had a positive impact on their food behavior. The experience of becoming the provider of their own food changes the students' food behaviors and representations., Conclusions: Diet quality, patterns of commensality and social representations of food provide input for developing healthy diet care and health promotion.

Chicken Expressed Sequence Tags (ESTs) were analyzed to identify genes associated with myogenesis during embryonic development. A total of 6,184 ESTs were generated from three cDNA libraries constructed from whole embryos (Stage 26), somites associated with neural tube (Stage 15), and limb buds (Stages 21, 24 and 26). Clustering and assembly of 4,998 valid ESTs resulted in 2,329 unique sequences with 902 clusters (38.7%) and 1,427 singletons (61.3%). There are more than 400,000 chicken ESTs available at GenBank and we were able to identify 143 novel sequences. From these, 45 sequences found either a human EST homolog or a match with conserved regions among proteins. Most of these sequences were found to be expressed in somites, an important tissue for muscle development and not characterized before. This study revealed the value of micro dissected embryonic libraries for describing gene expression profiles associated with myogenesis and gene discovery.

Important advances have been made in understanding the genetic processes that control skeletal muscle formation. Studies conducted on quails detected a delay in the myogenic program of animals selected for high growth rates. These studies have led to the hypothesis that a delay in myogenesis would allow somitic cells to proliferate longer and consequently increase the number of embryonic myoblasts. To test this hypothesis, recently segmented somites and part of the unsegmented paraxial mesoderm were separated from the neural tube/notochord complex in HH12 chicken embryos. In situ hybridization and competitive RT-PCR revealed that MyoD transcripts, which are responsible for myoblast determination, were absent in somites separated from neural tube/notochord (1.06 and 0.06 10(-3) attomol MyoD/1 attomol beta-actin for control and separated somites, respectively; P<0.01). However, reapproximation of these structures allowed MyoD to be expressed in somites. Cellular proliferation was analyzed by immunohistochemical detection of incorporated BrdU, a thymidine analogue. A smaller but not significant (P = 0.27) number of proliferating cells was observed in somites that had been separated from neural tube/notochord (27 and 18 for control and separated somites, respectively). These results confirm the influence of the axial structures on MyoD activation but do not support the hypothesis that in the absence of MyoD transcripts the cellular proliferation would be maintained for a longer period of time.

The aim of this study was to examine the kinetics of neovascularisation of splenic autoimplants into the abdominal cavity after splenectomy in mice. Sixty-eight female Swiss mice were submitted to splenectomy. The spleen from each animal was sliced and the slices were implanted into the abdominal cavity. Groups of animals were killed after 1, 2, 3, 5, 7, 15, 21, 28, 42, 56, 70 and 84 d. Fluorescent polystyrene microspheres were injected via the orbital venous plexus before killing and the splenules were removed 5 min later for light and electron microscopy. Mesenteric blood vessels were injected with coloured latex to study the origin of the nutrient vessels. Three days after the implant the microspheres were observed at the periphery and then migrating to the internal parts of the implant in the subsequent days. The blood supply to the implants originated from branches of the splenic, short gastric, mesenteric and gastroepiploic arteries. It is concluded that revascularisation of splenic autografts proceeds centripetally, starting as early as 3 d after implantation.

Morphologic and functional changes in the spleen of BALB/cByJ mice in the course of Plasmodium chabaudi adami malaria were assessed by light and electron microscopy, augmented by probes of polystyrene spheres and autoradiography of injected 3H-uridine-labeled T lymphocytes. The initial phase of the disease (precrisis) was characterized by increasing parasitemia accompanied by a marked increase in spleen size and by anemia. Erythropoiesis predominated, but there was also plasmacytopoiesis and monocyte-macrophage differentiation. The white pulp increased due to enlargement of lymphatic nodules, and in the periarterial lymphatic sheath, plasma cells invade the area around the central artery. A decrease in splenic uptake was demonstrated by light microscopic analysis of concentration and distribution of intravenously injected, spleen-cleared polystyrene spheres. Stromal cells showing signs of intense protein secretion and increased branching were present. Branches of these cells, barrier cells, appeared to seal off from the blood the locules of filtration beds, protecting splenic erythropoiesis from parasitization. Barrier cells are recently recognized fibroblastic contractile stromal cells that fuse to form complex branched variform barriers used for such diverse functions as controlling blood flow and blood cell delivery into the circulation, sealing off the hematopoietic/immunologic colonies and regulating their proliferation and differentration through paracrine secretion. Normally present in marrow and spleen in limited numbers, barrier cells are quickly mobilized in hematopoietic/ immunologic stess. They may well be part of a larger system that includes the myofibroblasts of wound healing and myoepithelial cells. The following phase, crisis, was characterized by a sharp decrease in parasitemia, increased splenic uptake, and amelioration of the anemia. Again, the filtration beds were opened to the blood. In the succeeding phase of postcrisis, the structure of the spleen approached normalcy. Analysis of autoradiographs showed T cells from normal or immunized mice distributing equally to red pulp and white pulp at 1 hr after injection of isolated radioactively labeled T cells, but they increased in white pulp over time. A higher percentage of immune cells was found in the white pulp of mice on day 16 of infection, suggesting a role for these cells in the development of crisis. Interleukin-I-treated mice developed higher levels of parasitemia and lower levels of splenic uptake.

The dissection of nerves and ganglia anatomically related to the pelvic organs revealed one inferior mesenteric ganglion, two testicular ganglia, two hypogastric nerves, two pelvic ganglia and two pelvic nerves. The histochemical demonstration of catecholamines by a glyoxylic acid fluorescence method revealed a rich sympathetic innervation in the ductus deferens, in the three segments of the prostate and in the convoluted ductuli efferentes. The testis, epididymis and all three pairs of bulbourethral glands presented fluorescent nerve fibers only around blood vessels. Removal of the inferior mesenteric and testicular ganglia, and hypogastric neurectomy with our without ligature and sectioning of testicular arteries, had no effect on the density of the nonvascular fluorescent fibers. Removal of the periprostatic tissue caused complete denervation of the prostate and marked denervation of the ductuli efferentes and ductus deferens. Small ganglia containing fluorescent nerve cell bodies were found close to the capsule of the prostate. The results indicate that short adrenergic neurons are responsible for the sympathetic innervation of the reproductive organs of the male opossum.