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Abstract Introduction Stomal recurrence is a troublesome complication after total laryngectomy. Despite a large number of studies having been performed, there is still controversy about which risk factors are most significant for the development of stomal recurrence. Objective The objective of the present meta-analysis was to analyze the potential factors leading to stomal recurrence after total laryngectomy. Methods PubMed, Web of Science, Cochrane Library, and Ovid databases were systematically searched using multiple search terms. Eighteen studies with 6462 patients were identified. The quality of evidence was assessed by The National Institute for Health and Clinical Excellence. Results The results showed that, tumor subsite (supraglottic vs. subglottic, RR = 0.292, 95% CI 0.142-0.600, p = 0.001; glottic vs. subglottic, RR = 0.344, 95% CI 0.175-0.676, p = 0.002), T stage (RR = 0.461, 95% CI 0.286-0.742, p = 0.001), preoperative tracheotomy (RR = 1.959, 95% CI 1.500-2.558, p < 0.001) were the high-risk factors associated with the development of stomal recurrence. Conclusion From the results of our study, tumor subsite, T stage and preoperative tracheotomy were the significant risk factors for stomal recurrence. Methodologically high-quality comparative investigations are needed for further evaluation.

Resumo Introdução A recorrência estomal pós-laringectomia total e é uma complicação de difícil manejo. Apesar de um grande número de estudos ter sido feito, ainda há controvérsias sobre quais fatores de risco são mais significativos para o seu desenvolvimento. Objetivo O objetivo da presente meta-análise foi analisar os fatores potenciais para recorrência estomal após a laringectomia total. Método As bases de dados PubMed, Web of Science, Cochrane Library e Ovid foram sistematicamente pesquisadas com vários termos de busca. Dezoito estudos com 6.462 pacientes foram identificados. A qualidade da evidência foi avaliada pelo National Institute for Health and Clinical Excellence. Resultados Os resultados mostraram que o subsítio tumoral (supraglótico vs. subglótico, RR = 0,292, IC 95% 0,142 ± 0,600, p = 0,001; glótico vs. subglótico, RR = 0,344, IC 95% 0,175 ± 0,676, p = 0,002), estágio T (RR = 0,461, IC 95% 0,286 ± 0,742, p = 0,001), traqueotomia pré-operatória (RR = 1,959, IC 95% 1.500 ± 2.558, p < 0,001) foram os fatores de alto risco associados ao desenvolvimento de recorrência estomal. Conclusão Com base nos resultados de nosso estudo, o subsítio do tumor, o estágio T e a traqueotomia pré-operatória foram fatores de risco significativos para recorrência estomal. São necessárias investigações comparativas metodologicamente de alta qualidade para maior avaliação.

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INTRODUCTION: Stomal recurrence is a troublesome complication after total laryngectomy. Despite a large number of studies having been performed, there is still controversy about which risk factors are most significant for the development of stomal recurrence. OBJECTIVE: The objective of the present meta-analysis was to analyze the potential factors leading to stomal recurrence after total laryngectomy. METHODS: PubMed, Web of Science, Cochrane Library, and Ovid databases were systematically searched using multiple search terms. Eighteen studies with 6462 patients were identified. The quality of evidence was assessed by The National Institute for Health and Clinical Excellence. RESULTS: The results showed that, tumor subsite (supraglottic vs. subglottic, RR=0.292, 95% CI 0.142-0.600, p=0.001; glottic vs. subglottic, RR=0.344, 95% CI 0.175-0.676, p=0.002), T stage (RR=0.461, 95% CI 0.286-0.742, p=0.001), preoperative tracheotomy (RR=1.959, 95% CI 1.500-2.558, p<0.001) were the high-risk factors associated with the development of stomal recurrence. CONCLUSION: From the results of our study, tumor subsite, T stage and preoperative tracheotomy were the significant risk factors for stomal recurrence. Methodologically high-quality comparative investigations are needed for further evaluation.

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Exosomes, a kind of extracellular vesicle, are promising therapeutic agents for spinal cord injury (SCI). This article aimed to investigate effects of exosomes secreted from miRNA-29b-modified bone marrow mesenchymal stem cells (BMSCs) on SCI. Exosomes were extracted from BMSCs transfected with miRNA-29b or negative control (miR NC). SCI rats were injected intravenously with exosomes (control exosomes, miRNA-29b exosomes) and BMSCs (miR NC, miRNA-29b) through the tail vein. The expression of miRNA-29b in spinal cord tissues of SCI rats was detected by qRT-PCR. The hind limb motor function was evaluated by Basso Beattie Bresnahan (BBB) score. The histopathological damage and neuronal regeneration in spinal cord tissues was observed by HE staining and immunohistochemistry, respectively. The injection of miRNA-29b exosomes and miRNA-29b BMSCs both significantly increased the expression of miRNA-29b in spinal cord tissues of SCI rats (P<0.05). Compared with SCI rats, rats in the miRNA-29b exosomes and the miRNA-29b groups exhibited improved SCI, including increased BBB score, NF200 and GAP-43 positive neurons, as well as decreased contractile nerve cell numbers and GFAP positive neurons (all P<0.05). The relieving degree of SCI was significantly higher in the miRNA-29b exosomes group than in the miRNA-29b BMSCs group (P<0.05). Exosomes secreted from miRNA-29b-modified BMSCs were effective in the repair of SCI in rats.

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Mercury emissions from biomass burning contribute significantly to the atmospheric mercury budget and the interannual variation of mercury concentrations in the troposphere. This study developed a high-resolution (0.1°â€¯× 0.1°) monthly inventory of mercury emissions from biomass burning across five land types in the tropical continents (Central and South America, Africa, and South and Southeast Asia) during 2001-2017. The inventory estimates of mercury emissions from biomass burning are based on the newly released MCD64A1 Version 6 Burned Area data product, satellite and observational data of biomass density, and spatial and temporal variable combustion factors. Results from the inventory demonstrated that during 2001-2017, the average annual mercury emissions from biomass burning in tropical continents was 497 Mg and ranged from 289 Mg to 681 Mg. Forest fires were the largest contributor, accounting for 61% (300 Mg) of the total mercury emissions from biomass burning, followed by fires in woody savanna/shrubland (30%, 151 Mg), savanna/grassland (7%, 35 Mg), peatland (1%, 6 Mg), and cropland (1%, 5 Mg). However, these proportions varied between the continents; in the Americas and Asia, the largest biomass burning emissions came from forest fires, and in Africa the largest emissions were from fires woody savanna/shrubland. Between the three continents, Africa released 41% of the mercury emissions from biomass burning (202 Mg year-1), Asia released 31% (154 Mg year-1), and the Americas released 28% (141 Mg year-1). The total mercury emissions from biomass burning in these tropical continents exhibited strong interannual variations from 2001 to 2017, with peak emissions in March and August to September, and forest fires were the primary land type controlling the interannual variations.

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Exosomes, a kind of extracellular vesicle, are promising therapeutic agents for spinal cord injury (SCI). This article aimed to investigate effects of exosomes secreted from miRNA-29b-modified bone marrow mesenchymal stem cells (BMSCs) on SCI. Exosomes were extracted from BMSCs transfected with miRNA-29b or negative control (miR NC). SCI rats were injected intravenously with exosomes (control exosomes, miRNA-29b exosomes) and BMSCs (miR NC, miRNA-29b) through the tail vein. The expression of miRNA-29b in spinal cord tissues of SCI rats was detected by qRT-PCR. The hind limb motor function was evaluated by Basso Beattie Bresnahan (BBB) score. The histopathological damage and neuronal regeneration in spinal cord tissues was observed by HE staining and immunohistochemistry, respectively. The injection of miRNA-29b exosomes and miRNA-29b BMSCs both significantly increased the expression of miRNA-29b in spinal cord tissues of SCI rats (P<0.05). Compared with SCI rats, rats in the miRNA-29b exosomes and the miRNA-29b groups exhibited improved SCI, including increased BBB score, NF200 and GAP-43 positive neurons, as well as decreased contractile nerve cell numbers and GFAP positive neurons (all P<0.05). The relieving degree of SCI was significantly higher in the miRNA-29b exosomes group than in the miRNA-29b BMSCs group (P<0.05). Exosomes secreted from miRNA-29b-modified BMSCs were effective in the repair of SCI in rats.

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Abstract Introduction Reconstruction with a free flap is routine in head and neck surgery because of better functional outcomes, improved esthetics, and generally higher success rates. Objective To evaluate the clinical outcomes in patients undergoing different microvascular free flap reconstructions. Methods This was a retrospective study of 93 patients undergoing reconstructions with free flaps from 2007 to 2015. Four types of free flap were performed: anterolateral thigh (76.3%), radial forearm (16.1%), fibula (4.3%) and jejunum (3.3%). Patients' demographic data were collected, and the outcomes measured included flap survival and complications. Postoperative functional and oncological outcome were also analyzed. Results The patients included 73 men and 20 women, with a mean age of 56.1 years. The most common tumor location was the tongue. Squamous cell carcinoma represented the vast majority of the diagnosed tumors (89.2%). The most common recipient vessels were the superior thyroid artery (77.4%) and the internal jugular vein (91.4%). Nine patients required emergency surgical re-exploration and the overall flap success rate was 90.3%. Venous thrombosis was the most common cause for re-exploration. Other complications included wound infection (5.4%), wound dehiscence (1.1%), partial flap necrosis (9.7%), fistula formation (10.8%), and 1 bleeding (1.1%). The majority of patients had satisfactory cosmetic and functional results of both donor site and recipient site after 46.7 months of mean follow-up. Conclusion Microsurgical free flap is shown to be a valuable and reliable method in head and neck surgery. It can be used safely and effectively with minimal morbidity in selected patients. The reconstruction can be performed by appropriately skilled surgeons with acceptable outcomes. Success rate appears to increase as clinical experience is gained.

Resumo Introdução Reconstrução com retalhos livres é um procedimento de rotina nas cirurgias de cabeça e pescoço devido aos melhores resultados funcionais e estéticos e às taxas de sucesso geralmente maiores. Objetivo Avaliar os desfechos clínicos de pacientes submetidos a diferentes reconstruções microvasculares com retalhos livres. Método Estudo retrospectivo de 93 pacientes submetidos à reconstruções com retalhos livres, de 2007 a 2015. Foram utilizados quatro tipos de retalho livre: coxa anterolateral (76,3%), antebraço radial (16,1%), fíbula (4,3%) e jejuno (3,3%). Os dados demográficos dos pacientes foram coletados e os parâmetros avaliados incluíram sobrevida e complicações. Os resultados funcionais e oncológicos pós-operatórios também foram analisados. Resultados Os pacientes incluíram 73 homens e 20 mulheres, com idade média de 56,1 anos. O local mais comum para o tumor foi a língua. O carcinoma de células escamosas representou a maioria dos tumores diagnosticados (89,2%). As artérias receptoras mais comuns foram a artéria tireóidea superior (77,4%) e a veia jugular interna (91,4%). Nove pacientes necessitaram de reexploração cirúrgica de emergência e a taxa de sucesso global do retalho foi de 90,3%. A trombose venosa foi a causa mais comum da reexploração. Outras complicações incluíram infecção da ferida cirúrgica (5,4%), deiscência da ferida (1,1%), necrose parcial do retalho (9,7%), formação de fístula (10,8%) e sangramento (1,1%). A maioria dos pacientes apresentou resultados estéticos e funcionais satisfatórios, tanto no local doador quanto no receptor, após 46,7 meses de seguimento médio. Conclusão O retalho livre microcirúrgico mostrou ser um método valioso e confiável na cirurgia de cabeça e pescoço. Pode ser usado de forma segura e eficaz, com morbidade mínima em pacientes selecionados. A reconstrução pode ser feita por cirurgiões adequadamente qualificados com resultados aceitáveis. A taxa de sucesso parece aumentar à medida que a experiência clínica é adquirida.

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INTRODUCTION: Reconstruction with a free flap is routine in head and neck surgery because of better functional outcomes, improved esthetics, and generally higher success rates. OBJECTIVE: To evaluate the clinical outcomes in patients undergoing different microvascular free flap reconstructions. METHODS: This was a retrospective study of 93 patients undergoing reconstructions with free flaps from 2007 to 2015. Four types of free flap were performed: anterolateral thigh (76.3%), radial forearm (16.1%), fibula (4.3%) and jejunum (3.3%). Patients' demographic data were collected, and the outcomes measured included flap survival and complications. Postoperative functional and oncological outcome were also analyzed. RESULTS: The patients included 73 men and 20 women, with a mean age of 56.1 years. The most common tumor location was the tongue. Squamous cell carcinoma represented the vast majority of the diagnosed tumors (89.2%). The most common recipient vessels were the superior thyroid artery (77.4%) and the internal jugular vein (91.4%). Nine patients required emergency surgical re-exploration and the overall flap success rate was 90.3%. Venous thrombosis was the most common cause for re-exploration. Other complications included wound infection (5.4%), wound dehiscence (1.1%), partial flap necrosis (9.7%), fistula formation (10.8%), and 1 bleeding (1.1%). The majority of patients had satisfactory cosmetic and functional results of both donor site and recipient site after 46.7 months of mean follow-up. CONCLUSION: Microsurgical free flap is shown to be a valuable and reliable method in head and neck surgery. It can be used safely and effectively with minimal morbidity in selected patients. The reconstruction can be performed by appropriately skilled surgeons with acceptable outcomes. Success rate appears to increase as clinical experience is gained.

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Background Head smut of maize, which is caused by Sporisorium reilianum f. sp. zeae (Kühn), is a serious disease in maize. In order to reveal the molecular mechanism of the resistance to head smut in maize, a microarray containing ~ 14,850 probes was used to monitor the gene expression profiles between a disease resistant near isogenic line (NIL) and a highly susceptible inbred line after S. reilianum was injected with an artificial inoculation method. Results Levels of expression for 3,532 genes accounting for 23.8% of the total probes changed after inoculation. Gene Ontology analysis revealed that the differentially expressed genes participated in physiological and biochemical pathways. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that plant-pathogen interaction, natural killer cell mediated cytotoxicity and benzoxazinoid biosynthesis pathways play important roles in resistance to head smut. Three head smut resistance-related candidate genes, CLAVATA1, bassinosteroid insensitive 1-associated receptor kinase 1 and LOC100217307 with leucine-rich repeat (LRR) conserved domains were identified, each of which is in maize mapping bin 2.09, a region previously shown to include a major QTL for head smut resistance. Furthermore, LOC100217307 was validated by quantitative real-time (qRT)-PCR inferring that this gene may be involved in the resistance to head smut of maize. Conclusions This study provided valuable information for cloning, functional analysis and marker assisted breeding of head smut resistance genes.

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Objetivo: Investigar os métodos cirúrgicos no tratamento de fratura de tornozelo de Weber tipo C e estimar a necessidade de exploração cirúrgica da sindesmose. Métodos: quarenta e três pacientes que apresentavam fratura de tornozelo de Weber tipo C foram tratados com redução aberta e fixação interna de outubro de 2004 a dezembro de 2009. Vinte e nove pacientes foram tratados com o procedimento de rotina, que envolve redução aberta e fixação interna, exploração de sindesmose. Nos outros pacientes, foram realizados reparos adicionais. Trinta e quatro pacientes foram acompanhados durante um período médio de 31,2 meses (faixa, 18 a 50 meses), 22 pacientes desse total foram tratados com procedimentos de rotina e 12 foram tratados com exploração cirúrgica adicional da sindesmose. Resultados: todas as fraturas estavam unidas no período médio de 13,1 semanas (faixa, 10 a 18 semanas), tendo início o apoio de peso total. A escala média de tornozelo e retropé do escore da American Orthopaedics Foot and Ankle Society foi 79,86 (faixa, 65 a 98) no grupo procedimentos de rotina e 86,67 (faixa, 78 a 100) no grupo exploração da sindesmose. Os valores do escore de Olerud-Molander foram 77,27 (faixa, 55 a 100) e 86,67 (faixa, 75 a 100), respectivamente. Constatou-se diferença estatisticamente significante entre os dois grupos (P < 0,05). Conclusão: A exploração cirúrgica da sindesmose é essencial em certas fraturas de tornozelo de Weber tipo C, que torna possível o desbridamento e a redução direta da sindesmose, permitindo maior estabilização da articulação do tornozelo. Nível de evidência III, Estudo retrospectivo comparativo .

Objective: To investigate the surgical methods in treating weber type c ankle injury and estimate the necessity of syndesmosis operative exploration. Methods: forty three patients presenting weber type c ankle injury were treated with open reduction and internal fixation from October 2004 to December 2009. Twenty nine patients were treated with routine procedure involving open reduction and internal fixation, syndesmosis exploration. Additional repair was performed in the others. Thirty four patients were followed during an average time of 31.2 months (range, 18 to 50 months), 22 patients of those were treated with routine procedures and 12 were treated with additional syndesmosis surgical exploration. Results: all the fractures were united within the average time of 13.1 weeks (range, 10 to 18 weeks) and full weight bearing began. The mean ankle and hindfoot scale of the American Orthopaedics Foot and Ankle Society score was 79.86 (range, 65 to 98) in the routine procedures group and 86.67 (range, 78 to 100) in the syndesmosis exploration group. The values of olerud-molander score were 77.27 (range, 55 to 100) and 86.67 (range, 75 to 100), respectively. Statistcally significant difference was found between the two groups (p<0.05). Conclusion: syndesmosis surgical exploration is essential in some weber type c ankle injuries, which make debridement and direct reduction of the syndesmosis possible, allowing higher stabilization of the ankle joint. Level of Evidence III, Retrospective Comparative Study.

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OBJECTIVE: To investigate the surgical methods in treating Weber type C ankle injury and estimate the necessity of syndesmosis operative exploration. METHODS: Forty three patients of Weber type C ankle injury were treated with open reduction and internal fixation from October 2004 to December 2009. Twenty nine patients were treated with routine procedure by open reduction and internal fixation, syndesmosis exploration and repair were performed in addition in the others. Thirty four patients were followed during an average time of 31.2 months (range 18 to 50 months), amomg them 22 patients were treated with routine procedures and 12 were treated with additional syndesmosis surgical exploration. RESULTS: All the fractures were reunited in an average time of 13.1 weeks (range 10 to 18 weeks) and full weight bearing began. The mean ankle and hindfoot scale of the American Orthopaedic Foot and Ankle Society (AOFAS) score was 79.86(range 65 to 98) in the routine procedures group and 86.67 (range 78 to 100) in the syndesmosis exploration group and Olerud-Molander score was 77.27 (range 55 to 100) and 86.67 (range 75 to 100) respectively. Statistically significant difference was found between the two groups (P<0.05). CONCLUSION: Syndesmosis surgical exploration is an essential treatment in some Weber type C ankle injuries, which make debridement and direct reduction of the syndesmosis possible, providing thus a more stabilized ankle joint. Level of Evidence III, Retrospective Comparative Study.

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OBJETIVO: Apresentar um desenho de placa em forma de borboleta e sua aplicação no tratamento de fraturas do calcâneo e discutir suas indicações clínicas, vantagens e desvantagens. MÉTODOS: De fevereiro de 2008 a abril de 2010, 22 pacientes com 26 fraturas intra-articulares do calcâneo foram tratados com redução a céu aberto e fixação interna com placa em forma de borboleta. Dezesseis pacientes eram homens e 6 eram mulheres, com média de idade de 36,8 anos. Onze eram pés esquerdos e 15, direitos. De acordo com a classificação de Sanders, 12 eram fraturas de calcâneo Tipo II (inclusive 3 Tipo IIa, 7 Tipo IIb e 2 Tipo IIc) e 14 eram Tipo III (inclusive cinco do Tipo IIIab, 7 Tipo IIIac e duas do Tipo IIIbc). RESULTADOS: Dezessete pacientes (21 pés) foram submetidos a acompanhamento por em média 19,2 meses. Os desfechos funcionais foram avaliados com o sistema Maryland Foot Score. Entre os nove pés com fraturas Tipo II, sete receberam escore excelente e dois, bom. Entre as 12 fraturas Tipo III, seis tiveram escore excelente, cinco, bom e uma, razoável. CONCLUSÃO: A placa em forma de borboleta é aplicável ao tratamento de fraturas do calcâneo do Tipo II e Tipo III de Sanders, com a vantagem de garantir fixação confiável, facilitar a cirurgia, produzir menos complicações pós-operatórias e produzir melhores desfechos clínicos gerais. Nível de Evidência IV, Série de casos.

OBJECTIVE: To introduce the design of butterfly-shaped plate and its application in treatment for calcaneal fractures, and to discuss its clinical indications, advantages and disadvantages. METHODS: From February 2008 to April 2010, 22 patients with 26 intra-articular calcaneal fractures were treated by open reduction and internal fixation with butterfly-shape plate. Sixteen patients were male and 6 patients were female, with a mean age of 36.8 years. Eleven were left feet and 15, right. According to Sanders classification, 12 were Type II (including 3 Type IIa, 7 Type IIb and 2 Type IIc) and 14 were Type III (including 5 Type IIIab, 7 Type IIIac and 2 Type IIIbc). RESULTS: Seventeen patients (21 feet) were followed-up for an average of 19.2 months. The functional outcomes were assessed using the Maryland Foot Score system. Among the 9 feet with Type II fractures, 7 feet were scored excellent, 2 were good. Among the 12 Type III fractures, 6 were scored excellent, 5 were good, and one was fair. CONCLUSION: The butterfly-shaped plate is applicable to treatment for Sanders Type II and Type III calcaneal fractures, with advantages of ensuring reliable fixation, easier operation, fewer post-operative complications, and better clinical outcomes. Level of Evidence IV, Case Series.

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OBJECTIVE: To introduce the design of a butterfly-shaped plate and its application in the treatment of calcaneal fractures, and to discuss its clinical indications, advantages and disadvantages. METHODS: From February 2008 to April 2010, 22 patients with 26 intra-articular calcaneal fractures were treated by open reduction and internal fixation with a butterfly-shaped plate. Sixteen patients were male and six patients were female, with a mean age of 36.8 years. Eleven were left feet and 15, right. According to the Sanders classification, 12 were calcaneal fractures Type II (including three Type IIa, seven Type IIb and two Type IIc) and 14 were Type III (including five Type IIIab, seven Type IIIac and two Type IIIbc). RESULTS: Seventeen patients (21 feet) were followed-up for an average of 19.2 months. The functional outcomes were assessed using the Maryland Foot Score system. Among the nine feet with Type II fractures, seven feet were scored excellent, two were good. Among the 12 Type III fractures, six were scored excellent, five were good, and one was scored fair. CONCLUSION: The butterfly-shaped plate is applicable in the treatment of Sanders Type II and Type III calcaneal fractures, with the advantages of ensuring reliable fixation, facilitating the surgery, producing fewer postoperative complications, and generating better overall clinical outcomes. Level of Evidence IV, Case Series.