Matteucinol combined with temozolomide inhibits glioblastoma proliferation, invasion, and progression: an in vitro, in silico, and in vivo study.

Glioblastoma is the most prevalent and malignant brain tumor identified in adults. Surgical resection followed by radiotherapy and chemotherapy, mainly with temozolomide (TMZ), is the chosen treatment for this type of tumor. However, the average survival of patients is around 15 months. Novel approaches to glioblastoma treatment are greatly needed. Here, we aimed to investigate the anti-glioblastoma effect of the combination of matteucinol (Mat) (dihydroxyflavanone derived from Miconia chamissois Naudin) with the chemotherapeutic TMZ in vitro using tumor (U-251MG) and normal astrocyte (NHA) cell lines and in vivo using the chick embryo chorioallantoic membrane (CAM) assay. The combination was cytotoxic and selective for tumor cells (28 µg/mL Mat and 9.71 µg/mL TMZ). Additionally, the combination did not alter cell adhesion but caused morphological changes characteristic of apoptosis in vitro. Notably, the combination was also able to reduce tumor growth in the chick embryo model (CAM assay). The docking results showed that Mat was the best ligand to the cell death membrane receptor TNFR1 and to TNFR1/TMZ complex, suggesting that these two molecules may be working together increasing their potential. In conclusion, Mat-TMZ can be a good candidate for pharmacokinetic studies in view of clinical use for the treatment of glioblastoma.

Matteucinol combined with temozolomide inhibits glioblastoma proliferation, invasion, and progression: an in vitro, in silico, and in vivo study

Glioblastoma is the most prevalent and malignant brain tumor identified in adults. Surgical resection followed by radiotherapy and chemotherapy, mainly with temozolomide (TMZ), is the chosen treatment for this type of tumor. However, the average survival of patients is around 15 months. Novel approaches to glioblastoma treatment are greatly needed. Here, we aimed to investigate the anti-glioblastoma effect of the combination of matteucinol (Mat) (dihydroxyflavanone derived from Miconia chamissois Naudin) with the chemotherapeutic TMZ in vitro using tumor (U-251MG) and normal astrocyte (NHA) cell lines and in vivo using the chick embryo chorioallantoic membrane (CAM) assay. The combination was cytotoxic and selective for tumor cells (28 μg/mL Mat and 9.71 μg/mL TMZ). Additionally, the combination did not alter cell adhesion but caused morphological changes characteristic of apoptosis in vitro. Notably, the combination was also able to reduce tumor growth in the chick embryo model (CAM assay). The docking results showed that Mat was the best ligand to the cell death membrane receptor TNFR1 and to TNFR1/TMZ complex, suggesting that these two molecules may be working together increasing their potential. In conclusion, Mat-TMZ can be a good candidate for pharmacokinetic studies in view of clinical use for the treatment of glioblastoma.

Autophagy and apoptosis interplay during follicular atresia in fish ovary: a morphological and immunocytochemical study.

Follicular atresia in fish ovary provides an interesting model for studying autophagy and apoptosis. In order to improve knowledge of the mechanisms regulating ovarian regression, we investigated the immunolocalisation of various proteins involved in the complex network of autophagy and apoptosis. Females of three species of freshwater fish maintained in captivity were sampled after the reproductive period and the main events of follicular atresia were assessed by histology: splits in the zona radiata, yolk degradation and reabsorption, hypertrophy of the follicular cells, accumulation of autophagic vacuoles, closing of the follicular lumen and thickening of the theca. The interplay of apoptosis and autophagy was analysed by TUNEL in situ and by immunocytochemistry for caspase-3, bax, bcl-2, beclin-1 and cathepsin-D. During early and advanced stages of follicular regression, the actin cytoskeleton was well developed and labelling for bcl-2 and cathepsin-D were pronounced in the follicular cells at a stage when they were intensively involved in yolk phagocytosis. Immunofluorescence for beclin-1 was prevalent in the follicular cells, punctate labelling often surrounding autophagic vacuoles during the advanced stage of follicular regression, a critical step towards cell death. TUNEL-positive reaction and immunostaining for bax and caspase-3 demonstrated the participation of apoptosis in late follicular regression. Overall, this study provides evidence that autophagic and apoptotic proteins are activated in a coordinated fashion depending on the stage of follicular regression, with interplay between autophagy and apoptosis being essential in determining the fate of the cell during follicular atresia in fish ovary.

Apoptosis, cell proliferation and vitellogenesis during the folliculogenesis and follicular growth in teleost fish.

Aiming to better understand folliculogenesis, this study evaluated cell death and proliferation of ovarian cells, besides cathepsin-D expression in Prochilodus argenteus captured in two sites of the São Francisco River downstream from the Três Marias Dam, Brazil. In the site immediately following the Dam (S1), low levels of dissolved oxygen were registered in the rainy period. The water temperature was higher in the São Francisco River immediately after the confluence with the Abaeté River (S2), regardless of the period. In S1, the ovaries showed smaller oocytes, high caspase-3 enzymatic activity and apoptosis, lower cells in proliferation and GSI, as well as a lesser quantity of cathepsin-D when compared to females captured from S2. Regarding relative frequency of ovarian structures, in the dry period, only oogonia and perinucleolar oocytes were found in fish ovaries from both sites. On the other hand, in the rainy period, the relative frequency of oogonia and perinucleolar oocytes decreased and the vitellogenic oocytes increased in S2. Postovulatory follicles were observed only in S2, whereas atretic follicles occurred at a higher frequency in S1. Our results showed that apoptosis, cell proliferation and cathepsina-D evaluation can be used as biomarkers of environmental impact.

Ovarian follicular atresia is mediated by heterophagy, autophagy, and apoptosis in Prochilodus argenteus and Leporinus taeniatus (Teleostei: Characiformes).

We investigated apoptosis, cell proliferation antigen (PCNA), and heat shock protein (HSP70) during ovarian follicular atresia in two freshwater teleost species from the São Francisco River basin, Brazil: curimatã-pacu, Prochilodus argenteus and piau-jejo, Leporinus taeniatus. Fishes were maintained in captivity after the reproductive period and ovarian regression was assessed by gonadosomatic index for three stages: early, advanced, and late regression. Follicular atresia was analysed by light and transmission electron microscopy, as well as by TUNEL and immunohistochemistry for HSP70 and PCNA. During early regression, atretic follicles exhibited zona pellucida breakdown, yolk degeneration, and hypertrophied follicular cells (e.g., granulosa in mammals). Intense heterophagy to engulf the yolk, and autophagy were detected in the follicular cells during advanced and late atresia. The TUNEL assay detected DNA fragmentation, mainly in late follicular atresia. The apoptosis rate of the follicular cells increased up to 10% during follicular atresia in both species and was negatively correlated with follicular area. Immunohistochemistry reaction for HSP70 stained the follicular cells strongly during advanced atresia, when they are intensively involved in yolk engulfment, whereas the reaction for PCNA labelled theca cells. We inferred that heterophagy, autophagy, and apoptosis contributed to follicular atresia in teleost ovaries, thereby achieving a more efficient removal of the degenerating oocyte and dying follicular cells. Additionally, HSP70 may protect the follicular cells before apoptosis when they are involved in yolk engulfment, and cell proliferation in the theca contributed to ovarian remodelling.

Long-term follow-up of cartilaginous tumors of the larynx.

BACKGROUND: Cartilaginous tumors of the larynx are uncommon. A literature review disclosed approximately 250 cases since 1816; the cricoid cartilage is the most common site. The rarity of these tumors has made for limited experience and, as a consequence, our knowledge is incomplete. OBJECTIVE: To report surgical results as well as long-term follow-up on 6 patients with cartilaginous tumors of the larynx. DESIGN: A 28-year retrospective study with the patients followed-up from 6 to 28 years (average, 17.8 years). METHODS: Six adult white male patients with cartilaginous tumors of the larynx: 4 low-grade chondrosarcoma (1 of the thyroid and 3 of the cricoid) and 2 chondroma of the cricoid. Surgical treatment included total laryngectomy of the thyroid and 1 of the cricoid chondrosarcoma, and conservation surgery of the other 4 cricoid tumors: the 2 patients with chondrosarcoma had total resection of the cricoid cartilage with thyrotracheal anastomosis, and the 2 patients with chondroma had local tumor resection using a laryngofissure approach. RESULTS: The margins of the specimen were negative for tumor in the 6 patients. On follow-up, none of the patients had regional or distant metastasis or tumor-related death. One of the patients with cricoid chondrosarcoma developed recurrence 8 years after conservation surgery, and required a total laryngectomy for salvage. Survival rate tumor-free at 5 years was 100% and at 10 years 67%, co-morbidity being responsible for the decrease in survival rate. CONCLUSIONS: Based on this small series of patients, the long-term follow-up of benign and low-grade malignant tumors suggests that the surgical approach and prognosis does not depend on histologic distinction and, importantly, underdiagnosed malignancy on tumor sampling and recurrent chondrosarcoma, managed with salvage surgery, have no adverse impact on patient survival. Total resection of the cricoid cartilage with thyrotracheal anastomosis over a stent proved an alternative surgical technique in chondrosarcoma who otherwise would have been treated by total laryngectomy.

The use of buccal mucosa graft at posterior cricoid splitting for subglottic stenosis repair.

BACKGROUND: Since 1955, when Réthi established the posterior cricoid split augmentation (PCSA) method, several authors have published supporting reports of the validity and proven efficacy of its basic principles. A 27-year prospective, retrospective study. OBJECTIVES: To report on experience in performing the PCSA method for subglottic and/or posterior-glottic stenosis repair using buccal mucosa interposition grafting at posterior cricoid split and stenting for 8 weeks, and to assess the impact on vocal function. METHODS: From 1972 on, 60 patients (45 adults, 15 children, aged 8 mo to 72 y) with subglottic and/or posterior-glottic stenosis were operated on using a modified PCSA method. The surgical technique consisted of posterior cricoid splitting, including or not the interarytenoid muscle; wide lateral retraction of the posterior cricoid halves; buccal mucosa interposition grafting and stenting for 8 weeks. The factors evaluated included the subglottic remodeling rate, donor and recipient sites morbidity, time to decannulation, rate of graft take, and phonatory function tests. RESULTS: The modified PCSA procedure resulted in a decannulation rate of 90%, 18 (30%) of which had further procedure to achieve decannulation, and 6 adult patients (10%) were considered failures because of restenosis. The rate of take of the mucosa graft was 100% in both children and adults, with complete epithelialization of the grafted area, the mucosa not becoming dry and crusty. No interarytenoid muscle division resulted in near-normal to normal glottic voicing. Interarytenoid muscle division determined supraglottic voicing with inspiratory noise and pneumophonic incoordination, breathy and hoarse voice, low fundamental frequency, limited dynamic range, and shortened phonation time. CONCLUSION: The PCSA procedure with buccal mucosa graft is reliable, safe, and highly successful with respect to the graft incorporation and subglottic remodeling. The division or not of the interarytenoid muscle is the most important factor influencing the postoperative vocal function.

Lateral thyrotomy approach on the paraglottic space for laryngocele resection.

OBJECTIVE: To report on the results of using a lateral thyrotomy approach on the paraglottic space to gain greater access for laryngocele resection under direct vision. STUDY DESIGN: A 26-year prospective and retrospective study. The study was conducted on 10 adult patients (5 men and 5 women) who had laryngocele of varying size on the paraglottic space. Six of the patients had internal laryngocele and four had exteriorized laryngocele. Five laryngoceles were left-sided, three were right-sided, and two were bilateral. METHODS: A V-shaped, full-thickness thyroid lamina resection with the triangle base at the superior border and the apex at a point midway of the thyroid lamina vertical extent was performed. RESULTS: A V-shaped lateral thyrotomy made exposure to the paraglottic space possible for direct submucosal laryngocele dissection. This approach has presented no complications to date. Postoperative minor edema or hematoma was found in the aryepiglottic and ventricular folds, but this disappeared within a few days. There was no recurrence; the minimum follow-up was 1 year. CONCLUSION: The triangular lateral thyrotomy approach provided access to the paraglottic space and superb visibility for resection of laryngocele of any size under direct vision, thus avoiding recurrence, morbidity, and complications.

The nurse practitioner: redefining occupational boundaries?

This paper explores aspects of the controversy and conflict that has arisen within the nursing and medical professions regarding the emergence of nurse practitioners in the United Kingdom (U.K.). Difficulties in establishing satisfactory definitions of nurse practitioners, that allow them to be viewed decisively either within nursing or medical occupational roles, are discussed. The paper argues that the key to the debate may hinge on professional and occupational boundary redefinition which is currently resisted by some members of both the nursing and medical professions. The idea that nurse practitioners may be an evolving and discrete professional group, outside the currently accepted professional and occupational definitions of nursing and medicine, is explored. It is argued that both nursing and medicine are faced with a particular challenge in the nurse practitioner movement that is resulting in conflict as new boundaries are established.

Posterior cricoidotomy lumen augmentation for treatment of subglottic stenosis in children.

OBJECTIVES: To determine the results of posterior cricoidotomy lumen augmentation in the treatment of moderate and severe subglottic stenosis in children, and to assess the effect of this surgery on the growth of the larynx in young children. DESIGN: A 17-year retrospective study. PATIENTS AND METHODS: Thirteen children with moderate and severe subglottic stenosis who underwent posterior cricoidotomy lumen augmentation from 1980 to 1996. Eight children (62%) were male and 5 (38%) were female. The average age was 4.7 years (age range, 8 months to 15 years). Six (46%) of the 13 children were younger than 3 years. Nine children (69%) had acquired subglottic stenosis, 3 of whom had a combined subglottic-posterior glottic stenosis, and 4 (31%) had congenital subglottic stenosis. All the children already had a tracheotomy tube placed and had undergone treatment at our clinic or at other institutions. The surgical procedure we used included a cricoid lamina split with grafting (2 children with costal cartilage graft and 11 with buccal mucosal graft) and stenting. RESULTS: Twelve (92%) of the 13 children underwent decannulation, and 1 (8%) is still undergoing treatment: decannulation is expected to be carried out in the near future. Of the 12 children who underwent decannulation, 9 demonstrated good postoperative voice quality and 3, who had combined subglottic-posterior glottic stenosis, developed impaired voice function. Following stent removal, all children experienced some degree of difficulty in swallowing saliva and liquids, which was soon overcome. No evidence of surgery-induced laryngeal growth impairment in younger children was observed. CONCLUSIONS: The posterior cricoidotomy lumen augmentation is a safe and effective technique for the treatment of moderate and severe subglottic stenosis in children of any age. This study lends further support to the assertion that external surgery does not affect the growth of the larynx in younger children.