Myxofibrosarcoma of the sphenoid sinus

Myxofibrosarcoma was originally described as the myxoid variant of malignant fibrous histiocytoma (MFH). It is uncommon in the head and neck region. We hereby report a case of myxofibrosarcoma in the sphenoid sinuses. The diagnostic and management difficulties are discussed. Close collaboration between surgeon, radiologist, histopathologist and clinical oncologist in makng accurate diagnosis and appropriate management of this rare tumour are emphasized.published_or_final_versio

Morphology of powerful suction organs from blepharicerid larvae living in raging torrents

BackgroundSuction organs provide powerful yet dynamic attachments for many aquatic animals, including octopus, squid, remora, and clingfish. While the functional morphology of suction organs from some cephalopods and fishes has been investigated in detail, there are only few studies on such attachment devices in insects. Here we characterise the morphology and ultrastructure of the suction attachment organs of net-winged midge larvae (genus Liponeura; Diptera: Blephariceridae) – aquatic insects that live on rocks in rapid alpine waterways where flow speeds can reach 3 m s− 1 – using scanning electron microscopy, confocal laser scanning microscopy, and X-ray computed micro-tomography (micro-CT). Furthermore, we study the function of these organs in vivo using interference reflection microscopy.ResultsWe identified structural adaptations important for the function of the suction attachment organs in L. cinerascens and L. cordata. First, a dense array of spine-like microtrichia covering each suction disc comes into contact with the substrate upon attachment, analogous to hairy structures on suction organs from octopus, clingfish, and remora fish. These spine-like microtrichia may contribute to the seal and provide increased shear force resistance in high-drag environments. Second, specialised rim microtrichia at the suction disc periphery were found to form a continuous ring in close contact and may serve as a seal on a variety of surfaces. Third, a V-shaped cut on the suction disc (“V-notch“) is actively opened via two cuticular apodemes inserting on its flanks. The apodemes are attached to dedicated V-notch opening muscles, thereby providing a unique detachment mechanism. The complex cuticular design of the suction organs, along with specialised muscles that attach to them, allows blepharicerid larvae to generate powerful attachments which can withstand strong hydrodynamic forces and quickly detach for locomotion.ConclusionThe suction organs from Liponeura are underwater attachment devices specialised for resisting extremely fast flows. Structural adaptations from these suction organs could translate into future bioinspired attachment systems that perform well on a wide range of surfaces

Laparoscopy in management of appendicitis in high-, middle-, and low-income countries: a multicenter, prospective, cohort study.

BACKGROUND: Appendicitis is the most common abdominal surgical emergency worldwide. Differences between high- and low-income settings in the availability of laparoscopic appendectomy, alternative management choices, and outcomes are poorly described. The aim was to identify variation in surgical management and outcomes of appendicitis within low-, middle-, and high-Human Development Index (HDI) countries worldwide. METHODS: This is a multicenter, international prospective cohort study. Consecutive sampling of patients undergoing emergency appendectomy over 6 months was conducted. Follow-up lasted 30 days. RESULTS: 4546 patients from 52 countries underwent appendectomy (2499 high-, 1540 middle-, and 507 low-HDI groups). Surgical site infection (SSI) rates were higher in low-HDI (OR 2.57, 95% CI 1.33-4.99, p = 0.005) but not middle-HDI countries (OR 1.38, 95% CI 0.76-2.52, p = 0.291), compared with high-HDI countries after adjustment. A laparoscopic approach was common in high-HDI countries (1693/2499, 67.7%), but infrequent in low-HDI (41/507, 8.1%) and middle-HDI (132/1540, 8.6%) groups. After accounting for case-mix, laparoscopy was still associated with fewer overall complications (OR 0.55, 95% CI 0.42-0.71, p < 0.001) and SSIs (OR 0.22, 95% CI 0.14-0.33, p < 0.001). In propensity-score matched groups within low-/middle-HDI countries, laparoscopy was still associated with fewer overall complications (OR 0.23 95% CI 0.11-0.44) and SSI (OR 0.21 95% CI 0.09-0.45). CONCLUSION: A laparoscopic approach is associated with better outcomes and availability appears to differ by country HDI. Despite the profound clinical, operational, and financial barriers to its widespread introduction, laparoscopy could significantly improve outcomes for patients in low-resource environments. TRIAL REGISTRATION: NCT02179112

Global variation in anastomosis and end colostomy formation following left-sided colorectal resection

Background End colostomy rates following colorectal resection vary across institutions in high-income settings, being influenced by patient, disease, surgeon and system factors. This study aimed to assess global variation in end colostomy rates after left-sided colorectal resection. Methods This study comprised an analysis of GlobalSurg-1 and -2 international, prospective, observational cohort studies (2014, 2016), including consecutive adult patients undergoing elective or emergency left-sided colorectal resection within discrete 2-week windows. Countries were grouped into high-, middle- and low-income tertiles according to the United Nations Human Development Index (HDI). Factors associated with colostomy formation versus primary anastomosis were explored using a multilevel, multivariable logistic regression model. Results In total, 1635 patients from 242 hospitals in 57 countries undergoing left-sided colorectal resection were included: 113 (6·9 per cent) from low-HDI, 254 (15·5 per cent) from middle-HDI and 1268 (77·6 per cent) from high-HDI countries. There was a higher proportion of patients with perforated disease (57·5, 40·9 and 35·4 per cent; P < 0·001) and subsequent use of end colostomy (52·2, 24·8 and 18·9 per cent; P < 0·001) in low- compared with middle- and high-HDI settings. The association with colostomy use in low-HDI settings persisted (odds ratio (OR) 3·20, 95 per cent c.i. 1·35 to 7·57; P = 0·008) after risk adjustment for malignant disease (OR 2·34, 1·65 to 3·32; P < 0·001), emergency surgery (OR 4·08, 2·73 to 6·10; P < 0·001), time to operation at least 48 h (OR 1·99, 1·28 to 3·09; P = 0·002) and disease perforation (OR 4·00, 2·81 to 5·69; P < 0·001). Conclusion Global differences existed in the proportion of patients receiving end stomas after left-sided colorectal resection based on income, which went beyond case mix alone

Symptomatic hypothalamic-pituitary dysfunction in nasopharyngeal carcinoma patients following radiation therapy: A retrospective study

Endocrine assessment was performed in 32 relapse-free southern Chinese patients (21 males and 11 females, aged 27-50 years at the time of assessment) 5-17 years following radiation therapy (RT) alone for early nasopharyngeal carcinoma (NPC). Initial screening was done using questionnaires emphasizing on impaired sexual function and menstrual disturbance plus measurement of serum levels of thyroxine, free thyroxine index, thyrotropic hormone, prolactin, and additionally testosterone for males only. Those showing abnormalities were subjected to detailed pituitary function tests. Hypothalamic-pituitary dysfunction was found in 7 female patients and only 1 male patient. A delayed TSH response to thyrotropin releasing hormone suggesting a hypothalamic disorder was seen in 6 of the affected female patients, and hyperprolactinaemia in also 6. None of the patients had evidence of diabetes insipidus. Hypopituitarism became symptomatic 2-5 years after RT with a mean latent interval of 3.8 years. A practical protocol for regular endocrine assessment for NPC patients after RT has been proposed. Multiple linear regression analysis of the radiotherapeutic data from the 11 female patients indicates that the likelihood of late occurrence of symptomatic hypothalamic-pituitary dysfunction following RT is dependent on the TDF of the target dose to the nasopharyngeal region and the height of the upper margin of the opposed lateral facial fields above the diaphragma sellae (coefficient of multiple correlation = 0.9025). Except when the sphenoid sinus or the middle cranial fossa is involved, it is advisable to set the height of the upper margin of the lateral facial field at a level no higher than the diaphragma sellae. The hypothalamus and possibly the pituitary stalk as well may sustain permanent damage by doses of radiation within the conventional radiotherapeutic range for carcinomas.link_to_subscribed_fulltex

Direct measurement of attachment of 220Rn progeny on aerosols by atomic force microscopy

Atomic force microscopy (AFM) is becoming a powerful tool for the study of nuclear tracks in materials such as CR-39. Coupled with its capability of observing near nm aerosol particles, we have utilized the AFM to observe the radon progeny-loaded aerosol particles deposited on surfaces of CR-39 and to observe the corresponding etch pits produced by the α-particles emitted from the radon progenies. A special platform was built so that after the aerosol particles on the CR-39 have been scanned and recorded, the CR-39 can be etched and then scanned for the etch pits at the same location. Both 222Rn and 220Rn progenies were used in the study. The progenies were generated by the appropriate radon sources and mixed with aerosol particles generated by aerosol generators. The aerosol size distributions were analyzed by a scanning mobility particle sizer. Some of the limitations and difficulties of the technique will be described. The results enable us to examine the attachment process including multiple attachments of radon progenies on aerosols. © 2003 Elsevier Science B.V. All rights reserved.link_to_subscribed_fulltex

Effects of cranial irradiation on hypothalamic-pituitary function - A 5-year longitudinal study in patients with nasopharyngeal carcinoma

The effects of cranial irradiation on hypothalamic-pituitary function were followed over a 5-year period in 31 adult patients with nasopharyngeal carcinoma. The estimated radiotherapy doses to the hypothalamus and pituitary were 3979 ± 78 (± SD) and 6167 ± 122 cGy, respectively. Within 2 years of radiotherapy, significant impairment in the secretion of growth hormone, gonadotrophins, corticotrophin and thyrotrophin were evident and 14 per cent of patients developed hyperprolactinaemia. Using life table analysis, the cumulative probability of endocrine dysfunction was estimated to be 62 per cent after 5 years with deficiencies in growth hormone, gonadotrophins, corticotrophin and thyrotrophin found in 63.5, 30.7, 26.7 and 14.9 per cent of patients, respectively. Growth hormone deficiency was the earliest endocrine dysfunction observed. Hyperprolactinaemia was uncommon in the male patients but occurred in five of eight women within 3 years of cranial irradiation. The alterations in gonadotrophin secretion suggest a defect in the pulsatile release of gonadotrophin releasing hormone. Twenty-eight patients developed a hypothalamic pattern of delayed thyrotrophin response to thyrotrophin releasing hormone one year after radiotherapy - four subsequently became hypothyroid. Patients who received radiotherapy for cervical lymph nodes were at greater risk of developing hypothyroidism. Thus, in these patients with no pre-existing disease in the hypothalamic-pituitary region, progressive impairment in hypothalamic pituitary function leading to endocrine dysfunction requiring treatment occurs in 50 per cent of patients 5 years after cranial irradiation. Regular endocrine assessment should be performed in all patients following cranial irradiation.link_to_subscribed_fulltex

A role of PTPN21 in neuron survival and degeneration

This journal suppl. entitled: 2016 Abstract SupplementBACKGROUND: Alzheimer’s disease (AD) chronically leads to dramatic neuronal loss, as they undergo apoptotic cell death, a direct consequence of the b-amyloid deposition or due to damage to their axon. The nervous system has an extremely poor regenerative capabilities and the adult brain’s potential at replacing neurons and regrowing axons is very limited. Therefore, recovering from AD faces many challenges. Moreover, the secondary response at the site establishes a toxic environment, quashing any tentative repair. Previously, our published results revealed that PTPN21 promotes neuron migration and survival via Elk-1 transcription factor, one of the transcription factors of Presenilin 1 (PS1). Henceforth, in this study we explore the potential role of PTPN21 in pathological changes in AD. METHODS: We used our established model of overexpressing PTPN21 or functional lost mutant for PTPN21 and expose the cells to high levels of amyloid precursor protein (APP), and quantify the levels of b-amyloid (1-42 & 1-40), PS1 and other AD’s markers using immunoblotting and ELISA assays. RESULTS: PTPN21 reduces the secretion of b-amyloid and importantly, our preliminary data showing significant PTPN21-dependent reduction of both PS1 levels and human b-Amyloid (1-42). Furthermore, PTPN21 promotes neuron survival through NRG3 pathway. CONCLUSIONS: To this end, our current study uncovered a link between PTPN21 and a specific mechanism of via PS1 to reduce b-amplyoid production, of which, might help to slow the progression of AD.link_to_OA_fulltex