A influência da microbiota de doadores e do armazenamento do enxerto no transplante de córnea / Influence of donor microbiota and of graft storage on corneal transplantation

Introdução: O transplante de córneas é o principal tratamento para pessoas que apresentam distúrbios de curvatura ou transparência da córnea. No Brasil, não há protocolo unificado para meios de preservação, tempo de armazenamento e antibióticos utilizados. A preocupação é a de que patógenos possam ser transferidos aos receptores de transplantes. Objetivo: Realizar o levantamento da microbiota ocular de doadores de córneas a fim de verificar uma possível correlação com infecções em receptores e, dessa forma, auxiliar na melhoria de metodologias e protocolos de armazenamento de córneas. Método: Foi conduzido a partir de revisão da literatura, nas bases de dados PubMed, SciELO e nos portais: periódicos da CAPES, Anvisa, Ministério da Saúde e ABTO, entre 2018 e 2020. Resultados: Estudos baseados em cultivo de microrganismos trazem Staphylococcus coagulase negativa (SCN) de 30% a 100% das amostras isoladas de conjuntivas. Em menor quantidade estão Streptococcus, Corynebacterium e Propionibacterium. Bactérias Gramnegativas aparecem em número inferior, representadas pelos gêneros Haemophilus, Neisseria, Pseudomonas, Enterobacter, Escherichia, Proteus e Acinetobacter. Já as técnicas independentes de cultivo trazem Pseudomonas como a principal colonizadora da conjuntiva. Também apresentam uma diversidade maior de colonizadores, mostrando um potencial campo de estudos, no qual a superfície ocular pode ter uma diversidade muito maior de espécies e potenciais agentes patogênicos. Os principais meios de preservação utilizados no Brasil levam os antimicrobianos gentamicina e estreptomicina em sua composição, porém estudos têm mostrado que as bactérias presentes nos meios de preservação são resistentes a esses antibióticos. Conclusões: Os dados apontam para a necessidade de reavaliação da eficiência desses meios de preservação na descontaminação das córneas para transplante.

Introduction: Corneal transplantation it is the main treatment for people who have corneal curvature or transparency disorders. In Brazil, there is no unifed protocol on the means of preservation, storage time and antibiotics used. The concern is that pathogens are transferred to transplant recipients, causing eye infections after transplantation. Objective: Examine ocular microbiota of corneal donors, to verify a possible correlation with infections in recipients and thus assist in improving corneal storage methodologies and protocols. Method: Literature review conducted in PubMed, SciELO and the following websites: CAPES Journals, Anvisa, Brazilian Ministry of Health and ABTO, between 2018 and 2020. Results: Studies based on microorganism's cultivation show coagulase negative Staphylococcus in 30% to 100% of samples isolated from conjunctiva. In lesser quantities are Streptococcus, Corynebacterium and Propionibacterium. Gram-negative bacteria appear in much lower numbers, represented by the genera Haemophilus, Neisseria, Pseudomonas, Enterobacter, Escherichia, Proteus and Acinetobacter. On the other hand, results based on independent cultivation techniques bring Pseudomonas as the main colonizer of the conjunctiva. Also, they have a much greater diversity of colonizers, showing a potential feld of study. The ocular surface may have a much greater diversity of species and potential pathogens than was expected. The main means of preservation used in Brazil contain the antimicrobials gentamicin and streptomycin in their composition; however, several studies have shown that bacteria present in the means of preservation are resistant to these antibiotics. Conclusions: These data point to the need for a reassessment of the efciency of these means of preservation in decontaminating corneas for transplantation.

Does Hallux Valgus Exhibit a Deformity Inherent to the First Metatarsal Bone?

Hallux valgus is a common condition, and it still poses some challenges. The identification of factors associated with the development of the deformity is of paramount importance in obtaining a full correction of the disorder. Hallux pronation is one of the frequently found components, especially in larger deformities, but the cause and exact location of this condition are not fully understood. The aim of the present study was to investigate whether there is a rotational deformity inherent to the first metatarsal bone. A case-control study was conducted on patients with and without hallux valgus who were subjected to computed tomography with multiplanar reconstruction. Statistical analysis was performed by means of a mixed model adjusted for foot and gender to compare metatarsal rotation between cases and controls. Correlations between numerical quantitative measurements were investigated by means of Pearson's correlation coefficient obtained in a linear mixed model. A total of 82 feet (tests) were analyzed in the hallux valgus group and 64 feet (tests) in the control group (N = 146). The hallux valgus group was significantly different from the control group (p< .001). Mean metatarsal bone rotation was 15.36° (range 1.65° to 32.52°) in the hallux valgus group and 3.45° (range -7.40° to 15.56°) in the control group. The difference between the means was 11.9° (confidence interval 9.2° to 14.6°). In conclusion, patients with hallux valgus exhibited increased exclusive bone rotation of the first metatarsal toward pronation compared with the population without this condition.

Expression of neurotrophins and their receptors in primary osteosarcoma. / Expressão de neurotrofinas e de seus receptores no osteossarcoma primário.

OBJECTIVE: to determine the expression of neurotrophins and their tyrosine-kinase receptors in patients with osteosarcoma (OS) and their correlation with clinical outcomes. METHODS: we applied immunohistochemistry to biopsy specimens of patients consecutively treated for primary OS at a single institution between 2002 and 2015, analyzing them for expression receptors of tyrosine kinase A and B (TrKA and TrKB), neural growth factor (NGF) and brain derived neurotrophic factor (BDNF). Independently, two pathologists classified the immunohistochemical markers as negative (negative or weak focal) or positive (moderate focal/diffuse or strong focal/diffuse). RESULTS: we analyzed data from 19 patients (10 females and 9 males), with median age of 12 years (5 to 17.3). Tumors' location were 83.3% in the lower limbs, and 63.2% of patients had metastases at diagnosis. Five-year overall survival was 55.3%. BDNF was positive in 16 patients (84%) and NGF in 14 (73%). TrKA and TrKB presented positive staining in four (21,1%) and eight (42,1%) patients, respectively. Survival analysis showed no significant difference between TrK receptors and neurotrophins. CONCLUSION: primary OS samples express neurotrophins and TrK receptors by immunohistochemistry. Future studies should explore their role in OS pathogenesis and determine their prognostic significance in larger cohorts.

OBJETIVO: determinar a expressão de neurotrofinas e seus receptores tirosina quinases em pacientes com osteossarcoma (OS) e sua correlação com desfechos clínicos. MÉTODOS: biópsias de tumores primários de pacientes com OS tratados em uma única instituição, consecutivamente, entre 2002 e 2015, foram analisados através de imuno-histoquímica para expressão de receptores de tirosina quinase A e B (TrKA e TrKB), fator de crescimento neural (NGF) e fator neurotrófico derivado do cérebro (BDNF). De forma independente, dois patologistas classificaram os marcadores de imuno-histoquímica como negativos (negativos e focais fracos) ou positivos (moderado focal/difuso ou forte focal/difuso). RESULTADOS: foram analisados dados de 19 pacientes (10 do sexo feminino e 9 do masculino) com mediana de idade de 12 anos (5 a 17,3 anos). Dos tumores, 83,3% estavam localizados em membros inferiores e 63,2% dos pacientes eram metastáticos ao diagnóstico. A sobrevida global em cinco anos foi de 55,3%. BDNF foi positivo em 16 pacientes (84%) e NGF em 14 pacientes (73%). TrKA e TrKB apresentaram coloração positiva em quatro (21,1%) e oito (42,1%) pacientes, respectivamente. A análise de sobrevida não demonstrou diferença significativa entre receptores TrK e neurotrofinas. CONCLUSÃO: amostras de OS primário expressam neurotrofinas e receptores TrK através de imuno-histoquímica. Estudos futuros podem auxiliar na identificação do papel das mesmas na patogênese do OS e determinar se há possível correlação prognóstica.

Expressão de neurotrofinas e de seus receptores no osteossarcoma primário / Expression of neurotrophins and their receptors in primary osteosarcoma

RESUMO Objetivo: determinar a expressão de neurotrofinas e seus receptores tirosina quinases em pacientes com osteossarcoma (OS) e sua correlação com desfechos clínicos. Métodos: biópsias de tumores primários de pacientes com OS tratados em uma única instituição, consecutivamente, entre 2002 e 2015, foram analisados através de imuno-histoquímica para expressão de receptores de tirosina quinase A e B (TrKA e TrKB), fator de crescimento neural (NGF) e fator neurotrófico derivado do cérebro (BDNF). De forma independente, dois patologistas classificaram os marcadores de imuno-histoquímica como negativos (negativos e focais fracos) ou positivos (moderado focal/difuso ou forte focal/difuso). Resultados: foram analisados dados de 19 pacientes (10 do sexo feminino e 9 do masculino) com mediana de idade de 12 anos (5 a 17,3 anos). Dos tumores, 83,3% estavam localizados em membros inferiores e 63,2% dos pacientes eram metastáticos ao diagnóstico. A sobrevida global em cinco anos foi de 55,3%. BDNF foi positivo em 16 pacientes (84%) e NGF em 14 pacientes (73%). TrKA e TrKB apresentaram coloração positiva em quatro (21,1%) e oito (42,1%) pacientes, respectivamente. A análise de sobrevida não demonstrou diferença significativa entre receptores TrK e neurotrofinas. Conclusão: amostras de OS primário expressam neurotrofinas e receptores TrK através de imuno-histoquímica. Estudos futuros podem auxiliar na identificação do papel das mesmas na patogênese do OS e determinar se há possível correlação prognóstica.

ABSTRACT Objective: to determine the expression of neurotrophins and their tyrosine-kinase receptors in patients with osteosarcoma (OS) and their correlation with clinical outcomes. Methods: we applied immunohistochemistry to biopsy specimens of patients consecutively treated for primary OS at a single institution between 2002 and 2015, analyzing them for expression receptors of tyrosine kinase A and B (TrKA and TrKB), neural growth factor (NGF) and brain derived neurotrophic factor (BDNF). Independently, two pathologists classified the immunohistochemical markers as negative (negative or weak focal) or positive (moderate focal/diffuse or strong focal/diffuse). Results: we analyzed data from 19 patients (10 females and 9 males), with median age of 12 years (5 to 17.3). Tumors' location were 83.3% in the lower limbs, and 63.2% of patients had metastases at diagnosis. Five-year overall survival was 55.3%. BDNF was positive in 16 patients (84%) and NGF in 14 (73%). TrKA and TrKB presented positive staining in four (21,1%) and eight (42,1%) patients, respectively. Survival analysis showed no significant difference between TrK receptors and neurotrophins. Conclusion: primary OS samples express neurotrophins and TrK receptors by immunohistochemistry. Future studies should explore their role in OS pathogenesis and determine their prognostic significance in larger cohorts.

Clinical, laboratory and densitometric comparison of patients with coxarthrosis and femoral neck fractures. / Comparação clínica, laboratorial e densitométrica de pacientes com coxartrose e com fraturas do colo femoral.

OBJECTIVE: to compare clinical, laboratory and densitometric data from patients with osteoarthrosis and femoral neck fractures. METHODS: we conducted a cross-sectional study of patients with femoral neck fracture and hip osteoarthrosis submitted to hip arthroplasty. We collected clinical, laboratory and densitometric data. RESULTS: we included 53 patients, 22 with femoral neck fractures and 31 with osteoarthrosis. Patients with femoral neck fractures were older than patients with osteoarthrosis, with lower BMI values, bone mineral density and palmar grip strength (sarcopenic patients), being more neurologically impaired and presenting a worse ASA score. Among the various biochemical parameters analyzed, we found statistically significant differences in total serum calcium, ionized calcium, vitamin D, free thyroxine, erythrocytes, hemoglobin, hematocrit, total white blood cells, neutrophils, lymphocytes and creatinine between the two groups. Other hormones analyzed and biochemical parameters did not differ significantly, although they showed trends between the two groups. CONCLUSION: patients with femoral neck fractures are older than patients with osteoarthrosis, have a lower weight and BMI, are more debilitated, many with anemia and reduced bone mass, and have a significant decrease in total calcium, ionized calcium, vitamin D and creatinine and a significant increase in free thyroxine.

Comparação clínica, laboratorial e densitométrica de pacientes com coxartrose e com fraturas do colo femoral / Clinical, laboratory and densitometric comparison of patients with coxarthrosis and femoral neck fractures

RESUMO Objetivo: comparar dados clínicos, laboratoriais e densitométricos de pacientes com osteoartrose e com fratura do colo femoral. Métodos: estudo transversal de pacientes com fratura do colo femoral e osteoartrose do quadril, submetidos à artroplastia de quadril. Dados clínicos, laboratoriais e densitométricos foram coletados. Resultados: cinquenta e três pacientes foram incluídos, 22 com fraturas do colo femoral e 31 com osteoartrose. Pacientes com fratura do colo do fêmur apresentaram maior idade do que os pacientes com osteoartrose, tendo valores de IMC, densidade mineral óssea e força de preensão palmar (pacientes sarcopênicos) inferiores, estando mais incapacitados neurologicamente e apresentando um pior escore ASA. Entre os vários parâmetros bioquímicos analisados, diferenças estatisticamente significantes foram encontrados no cálcio sérico total, cálcio ionizado, vitamina D, tiroxina livre, eritrócitos, hemoglobina, hematócrito, glóbulos brancos totais, neutrófilos, linfócitos e creatinina entre os dois grupos. Outros hormônios analisados e parâmetros bioquímicos não diferiram significativamente, apesar de mostrarem tendências entre os dois grupos. Conclusão: pacientes com fraturas do colo do fêmur são mais idosos do que pacientes com osteoartrose, apresentam um menor peso e IMC, são mais debilitados, muitos com anemia e massa óssea reduzida, além de terem uma diminuição significativa no cálcio total, cálcio ionizado, vitamina D e creatinina e um aumento significativo na tiroxina livre.

ABSTRACT Objective: to compare clinical, laboratory and densitometric data from patients with osteoarthrosis and femoral neck fractures. Methods: we conducted a cross-sectional study of patients with femoral neck fracture and hip osteoarthrosis submitted to hip arthroplasty. We collected clinical, laboratory and densitometric data. Results: we included 53 patients, 22 with femoral neck fractures and 31 with osteoarthrosis. Patients with femoral neck fractures were older than patients with osteoarthrosis, with lower BMI values, bone mineral density and palmar grip strength (sarcopenic patients), being more neurologically impaired and presenting a worse ASA score. Among the various biochemical parameters analyzed, we found statistically significant differences in total serum calcium, ionized calcium, vitamin D, free thyroxine, erythrocytes, hemoglobin, hematocrit, total white blood cells, neutrophils, lymphocytes and creatinine between the two groups. Other hormones analyzed and biochemical parameters did not differ significantly, although they showed trends between the two groups. Conclusion: patients with femoral neck fractures are older than patients with osteoarthrosis, have a lower weight and BMI, are more debilitated, many with anemia and reduced bone mass, and have a significant decrease in total calcium, ionized calcium, vitamin D and creatinine and a significant increase in free thyroxine.

Comparison between Simple Radiographic and Computed Tomographic Three-Dimensional Reconstruction for Evaluation of the Distal Metatarsal Articular Angle.

The hallux valgus is a pathologic condition in the forefoot that often causes pain and functional limitations. Assessing all deformity components, such as the distal metatarsal articular angle (DMAA) is essential to hallux valgus treatment. Nevertheless, interobserver agreement of DMAA is poor on plain radiographs. The present study compared computed tomographic (CT) 3-dimensional (3D) reconstruction with plain radiographic measurements for measuring the DMAA. We included 43 consecutive patients (77 feet), diagnosed with hallux valgus at the orthopedic outpatient clinic at Hospital de Clínicas de Porto Alegre (Porto Alegre, Brazil) from April 2014 to June 2015 in our prospective study. The DMAAs were measured by 2 observers using CT 3D reconstruction. The results were compared between observers and with the plain radiographic measurements using the concordance correlation coefficient and the Bland-Altman plot to determine the agreement between the 2 methods. The interobserver agreement of the CT 3D measurements was high (concordance correlation coefficient 0.90; p < .001). Significant agreement was found between the plain radiographic and CT measurements (concordance correlation coefficient 0.667; p < .001). The Bland-Altman plot showed that the difference between the plain radiographic and CT measurements increased when greater DMAA values were associated with the presence of metatarsal rotation. The interobserver agreement of DMAA measurements was greater on CT 3D reconstruction than on plain radiography. The poor interobserver agreement of the radiographic DMAA might have resulted from metatarsal rotation.

Lyophilized xenograft: a case series of histological analysis of biopsies.

The reconstruction of an acetabular bone defect is one of the most important aspects of revision total hip arthroplasty surgery. It can be done by the use of grafts. Therefore, many kinds of grafts may be used and lyophilized xenograft is an alternative example. The purpose of the study was to evaluate the histological findings of lyophilized bovine xenografts used in previous total hip arthroplasty revision surgery. A case series was carried out from July 2000 to April 2013 with the approval of the Hospital Ethics Committee. Fourteen subjects were analyzed. Of these, 64.3 % were female. The average age of the patients was 52.36 ± 18.55. Neoformed bone was present in 85.7 % of subjects, and constituted 61.79 % of the total bone matrix area. The diagnosis of xenograft absorption was present in 12 subjects. A strong inverse correlation between the percentage of neoformed bone and the percentage of xenograft in the total bone matrix by analysis of biopsies was found by the Pearson test (p = 0.001). No inflammatory response was found in the clinical status of the patients or in the histological analysis. Lyophilized bovine xenograft shown to be safe until the present moment, with acceptable results. Most of the cases presented new bone formation as expected (considered values greater than 30 %) and for this reason the xenograft has proven to be an osteoconductive compatible scaffold/trellis for the bone ingrowth. Therefore, it can be considered an alternative to other bone grafts in the treatment of bone loss.