Crescimento, defesas e herbivoria em folhas jovens de Qualea parviflora (Vochysiaceae) em três diferentes habitats de Cerrado

Insect herbivory is strongly influenced by the properties of their host leaves. Otherwise, such influence may be mediated by the environment in which the host plant is found. We examined three characteristics that may influence insect herbivory on young leaves of Qualea parviflora Mart. (Vochysiaceae), a widespread tree of the Brazilian Cerrado: leaf expansion rate, sclerophylly (leaf toughness), and tannin concentration during four consecutive months. Herbivory rates were measured on four marked intact leaves in five trees in three different physiognomies of the Cerrado biome: campo sujo (grassland), cerrado sensu stricto (savanna), and cerradão (woodland). Sclerophylly was higher in February while the highest concentration of tannins occurred in November but no variation in the rates of herbivory among months and physiognomies was found. A tendency of higher mean leaf growth rates was observed in the “cerradao” (1.03%) and “cerrado” (1.04%) in comparison with the campo sujo trees (0.86%). Higher sclerophylly and lower expansion rates and leaf size were observed in trees of the campo sujo. There was a tendency for higher herbivory rates in cerrado (10.5%), where the leaves showed lower concentration of tannins (1.5%) than in cerradão (2.1%). New leaves of Q. parviflora showed higher tannins concentration and lower damage than fully expanded leaves. Final leaf area explained 24% of the variation in total herbivory. Leaf size and associated nutritional factors exerted stronger influence on herbivory than defensive compounds on young leaves of Q. parviflora. Key words: Cerrado, leaf age, leaf growth, Neotropical savanna, plant defenses, sclerophylly.A herbivoria por insetos é fortemente influenciada pelas propriedades das folhas hospedeiras. No entanto, esta influência pode ser mediada por condições ambientais do habitat da planta. Neste estudo foram examinadas três características que podem influenciar a herbívora por insetos em folhas jovens de Qualea parvifl ora Mart. (Vochysiaceae), uma árvore comum do Cerrado brasileiro: taxa de expansão foliar, esclerofilia (rigidez foliar) e concentração de taninos. As taxas de herbívora foram medidas em quatro folhas intactas de cinco árvores em três diferentes fitofisionomias do bioma Cerrado: “campo sujo”, “cerrado sensu stricto” e “cerradão”. A esclerofilia foi maior em Fevereiro enquanto altas concentrações de taninos ocorreram em Novembro. No entanto, não foi observada variação nas taxas de herbívora entre os meses e entre fisionomias. Uma tendência em maiores taxas de crescimento foliar foi observada em árvores ocorrentes no “cerradão” (1,03%) e no “cerrado” (1,04%) em comparação com as ocorrentes no “campo sujo” (0,86%). Maiores valores de esclerofilia, baixas taxas de expansão foliar e menor tamanho foliar foram observadas no “campo sujo”. Houve uma tendência em altas taxas de herbívora no “cerrado” (10,5%), onde as folhas apresentaram concentrações de taninos mais baixas (1,5%) que no “cerradão” (2,1%). As folhas jovens de Q. parviflora apresentaram maiores concentrações de taninos e menor dano por herbívora que folhas maduras. A área foliar final explicou 24% da variação da herbívora total. O tamanho das folhas e fatores nutricionais associados exerceram influências mais fortes na herbívora que a concentração de compostos de defesa em folhas jovens de Q. parviflora. Palavras-chave: Cerrado, crescimento foliar, defesa de plantas, esclerofilia, idade foliar, savana neotropical

Cellular density and variability in laryngeal and pharyngeal squamous cell carcinoma using confocal laser endomicroscopy

OBJECTIVE: Confocal laser endomicroscopy (CLE) allows the visualization of epithelium in a thousand-fold magnification. This study analyzes the architectural differences at the cellular level of the mucosa and squamous cell carcinoma (SCC). PATIENTS AND METHODS: A total of 60 CLE sequences recorded in 5 patients with SCC undergoing laryngectomy between October 2020 and February 2021 were analyzed. The corresponding histologic sample derived from H&E staining was assigned to each sequence, capturing CLE images of the tumor and healthy mucosa. In addition, the cellular structure analysis was performed to diagnose SCC by measuring the total number of cells and cell size in 60 sequences in a fixed field of view (FOV) with 240 μm in diameter (45,239 μm2). RESULTS: Out of 3,600 images, 1,620 (45%) showed benign mucosa and 1,980 (55%) SCC. The automated analysis yielded a difference in cell size, with healthy epithelial cells being 171.9±82.0 μm2 smaller than SCC cells, which were 246.3±171.9 μm2 and showed greater variability in size (p=0.037). In addition, due to the probe’s fixed FOV, there was a difference in cell count with a total of 188.7±38.3 and 124.8±38.6 cells in images of normal epithelium and SCC (p<0.001), respectively. Regarding cell density as a criterion for the differentiation of benign/malign, using a cut-off value of 145.5 cells/FOV, we obtained sensitivity and specificity of 88.0% and 71.9%, respectively. CONCLUSIONS: SCC reveals marked differences at a cellular level compared to the healthy epithelium. Our results further support the importance of this feature for identifying SCC during CLE imaging

Safety and efficacy of non-steroidal anti-inflammatory drugs to reduce ileus after colorectal surgery

Background: Ileus is common after elective colorectal surgery, and is associated with increased adverse events and prolonged hospital stay. The aim was to assess the role of non-steroidal anti-inflammatory drugs (NSAIDs) for reducing ileus after surgery. Methods: A prospective multicentre cohort study was delivered by an international, student- and trainee-led collaborative group. Adult patients undergoing elective colorectal resection between January and April 2018 were included. The primary outcome was time to gastrointestinal recovery, measured using a composite measure of bowel function and tolerance to oral intake. The impact of NSAIDs was explored using Cox regression analyses, including the results of a centre-specific survey of compliance to enhanced recovery principles. Secondary safety outcomes included anastomotic leak rate and acute kidney injury. Results: A total of 4164 patients were included, with a median age of 68 (i.q.r. 57\u201375) years (54\ub79 per cent men). Some 1153 (27\ub77 per cent) received NSAIDs on postoperative days 1\u20133, of whom 1061 (92\ub70 per cent) received non-selective cyclo-oxygenase inhibitors. After adjustment for baseline differences, the mean time to gastrointestinal recovery did not differ significantly between patients who received NSAIDs and those who did not (4\ub76 versus 4\ub78 days; hazard ratio 1\ub704, 95 per cent c.i. 0\ub796 to 1\ub712; P = 0\ub7360). There were no significant differences in anastomotic leak rate (5\ub74 versus 4\ub76 per cent; P = 0\ub7349) or acute kidney injury (14\ub73 versus 13\ub78 per cent; P = 0\ub7666) between the groups. Significantly fewer patients receiving NSAIDs required strong opioid analgesia (35\ub73 versus 56\ub77 per cent; P &lt; 0\ub7001). Conclusion: NSAIDs did not reduce the time for gastrointestinal recovery after colorectal surgery, but they were safe and associated with reduced postoperative opioid requirement

Safety of hospital discharge before return of bowel function after elective colorectal surgery

Background: Ileus is common after colorectal surgery and is associated with an increased risk of postoperative complications. Identifying features of normal bowel recovery and the appropriateness for hospital discharge is challenging. This study explored the safety of hospital discharge before the return of bowel function. Methods: A prospective, multicentre cohort study was undertaken across an international collaborative network. Adult patients undergoing elective colorectal resection between January and April 2018 were included. The main outcome of interest was readmission to hospital within 30 days of surgery. The impact of discharge timing according to the return of bowel function was explored using multivariable regression analysis. Other outcomes were postoperative complications within 30 days of surgery, measured using the Clavien\u2013Dindo classification system. Results: A total of 3288 patients were included in the analysis, of whom 301 (9\ub72 per cent) were discharged before the return of bowel function. The median duration of hospital stay for patients discharged before and after return of bowel function was 5 (i.q.r. 4\u20137) and 7 (6\u20138) days respectively (P &lt; 0\ub7001). There were no significant differences in rates of readmission between these groups (6\ub76 versus 8\ub70 per cent; P = 0\ub7499), and this remained the case after multivariable adjustment for baseline differences (odds ratio 0\ub790, 95 per cent c.i. 0\ub755 to 1\ub746; P = 0\ub7659). Rates of postoperative complications were also similar in those discharged before versus after return of bowel function (minor: 34\ub77 versus 39\ub75 per cent; major 3\ub73 versus 3\ub74 per cent; P = 0\ub7110). Conclusion: Discharge before return of bowel function after elective colorectal surgery appears to be safe in appropriately selected patients