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Primary ciliary dyskinesia (PCD) is an autosomal recessive disease with an incidence estimated between 1:2,000 and 1:40,000. Ciliated epithelia line the airways, nasal and sinus cavities, Eustachian tube and fallopian tubes. Congenital abnormalities of ciliary structure and function impair mucociliary clearance. As a consequence, patients present with chronic sinopulmonary infections, recurrent glue ear and female subfertility. Similarities in the ultrastructure of respiratory cilia, nodal cilia and sperm result in patients with PCD also presenting with male infertility, abnormalities of left-right asymmetry (most commonly situs inversus totalis) and congenital heart disease. Early diagnosis is essential to ensure specialist management of the respiratory and otological complications of PCD. Diagnostic tests focus on analysis of ciliary function and electron microscopy structure. Analysis is technically difficult and labour intensive. It requires expertise for interpretation, restricting diagnosis to specialist centres. Management is currently based on the consensus of experts, and there is a pressing need for randomised clinical trials to inform treatment.

Manifestações otorrinolaringológicas em crianças com AIDS

Introduction: The study of otolaryngologic manifestations in children HIV + can lead to early diagnosis of AIDS, allowing specific treatment, responsible by reduced morbidity and mortality. Objectives: Detect the otolaryngologic manifestations in children with AIDS and alert to the importance of the early diagnosis. Study design: Clinical prospective. Material and method: We evaluated 22 children with AIDS assisted at Faculdade de Medicina de Botucatu (São Paulo, Brasil). The medical records were reviewed and the children were submitted to otolaryngologic and hearing acuity exams. Results: We evaluated 12 boys and 10 girls, whose ages ranged from 8 months to 12 years. In B and C clinical classification were included 18 children who were using anti-retroviral medicaments. Physical examination mainly indicated cervical lymphadenopathy (18 cases), paleness of the nasal mucous membrane with abundant mucous secretion over the nasal epithelium (15 cases) and retraction of tympanic membranes (seven cases). The main otolaryngologic diagnoses were: rhinosinusitis (16 cases), oral candidiasis (13 cases), inadequate eustachian tube function (seven cases) and recurrent tonsillar infections (six cases). Conductive hearing loss were detected in 4 children. No child presented sensorineural hearing loss. Conclusions: The main otolaryngologic manifestations presented by the children with HIV virus were rhinosinusitis, oral candidiasis, inadequate eustachian tube function and recurrent tonsillar infections. The allergic aspect of the nasal mucous membrane and the cervical lymphadenopathy were frequent signs and could alert the otolaryngologyst to AIDS during the exam.

Seqüência de moebius: Manifestações clínicas e avaliação auditiva

Introduction: Children with Moebius syndrome may present paralysis of cranial nerves III, IV, V, VI, VII, VIII, IX, X and XII, compromising motor and sensorial functions. Hands and feet defects (syndactyly, equinovarus and arthrogryposis) are frequently associated. These manifestations can be attributed to the use of misoprostol during pregnancy to induce abortion. Study design: Clinical prospective. Aim: To evaluate the main clinical manifestations, hearing acuity and possible etiologic factors in children with Moebius syndrome. Material and method: The children were submitted to clinical, otolaryngological and hearing acuity assessment. Hearing acuity was evaluated through behavioral tests, pure tone audiometry, tympanometry and auditory brainstem response (ABR). We investigated possible etiologic factors. Results: Three boys and two girls were evaluated. The main manifestations were: facial paralysis, paralysis of masseter muscle, defects in dental occlusion, retraction of tympanic membrane, equinovarus, oblique palpebral fissure and tongue atrophy. Conductive hearing loss was detected in three children and sensorineural hearing loss in one child. The use of misoprostol during pregnancy was reported by four mothers. Conclusions: The children with Moebius syndrome evaluated in the present study manifested palsies of various cranial nerves, especially V, VII and XII nerves, responsible for motor and sensorial alterations. Inadequate eustachian tube function associated to conductive hearing loss was frequent. The use of misoprostol during pregnancy was reported by the mothers and it was considered a possible etiologic factor.

Endonasal endoscopic exposure of the internal carotid artery: An anatomical study

Objectives/Hypothesis: The aim of this work was to define the anatomical landmarks, limitations, and difficulties of obtaining internal carotid artery (ICA) exposure via endonasal endoscopic approaches (EEA).

Primary ciliary dyskinesia

Primary ciliary dyskinesia (PCD) is an autosomal recessive disease with an incidence estimated between 1:2,000 and 1:40,000. Ciliated epithelia line the airways, nasal and sinus cavities, Eustachian tube and fallopian tubes. Congenital abnormalities of ciliary structure and function impair mucociliary clearance. As a consequence, patients present with chronic sinopulmonary infections, recurrent glue ear and female subfertility. Similarities in the ultrastructure of respiratory cilia, nodal cilia and sperm result in patients with PCD also presenting with male infertility, abnormalities of left-right asymmetry (most commonly situs inversus totalis) and congenital heart disease. Early diagnosis is essential to ensure specialist management of the respiratory and otological complications of PCD. Diagnostic tests focus on analysis of ciliary function and electron microscopy structure. Analysis is technically difficult and labour intensive. It requires expertise for interpretation, restricting diagnosis to specialist centres. Management is currently based on the consensus of experts, and there is a pressing need for randomised clinical trials to inform treatment.

The impact of delayed blood centrifuging, choice of collection tube, and type of assay on 25-hydroxyvitamin D concentrations

Studies have examined the associations between cancers and circulating 25-hydroxyvitamin D [25(OH)D], but little is known about the impact of different laboratory practices on 25(OH)D concentrations. We examined the potential impact of delayed blood centrifuging, choice of collection tube, and type of assay on 25(OH)D concentrations. Blood samples from 20 healthy volunteers underwent alternative laboratory procedures: four centrifuging times (2, 24, 72, and 96 h after blood draw); three types of collection tubes (red top serum tube, two different plasma anticoagulant tubes containing heparin or EDTA); and two types of assays (DiaSorin radioimmunoassay [RIA] and chemiluminescence immunoassay [CLIA/LIAISON®]). Log-transformed 25(OH)D concentrations were analyzed using the generalized estimating equations (GEE) linear regression models. We found no difference in 25(OH)D concentrations by centrifuging times or type of assay. There was some indication of a difference in 25(OH)D concentrations by tube type in CLIA/LIAISON®-assayed samples, with concentrations in heparinized plasma (geometric mean, 16.1 ng ml−1) higher than those in serum (geometric mean, 15.3 ng ml−1) (p = 0.01), but the difference was significant only after substantial centrifuging delays (96 h). Our study suggests no necessity for requiring immediate processing of blood samples after collection or for the choice of a tube type or assay.

Deposition of hydroxyapatite and calcium oxalate dihydrate on a heat exchanger tube

Most studies on the characterisation of deposits on heat exchangers have been based on bulk analysis, neglecting the fine structural features and the compositional profiles of layered deposits. Attempts have been made to fully characterise a fouled stainless steel tube obtained from a quintuple Roberts evaporator of a sugar factory using X-ray diffraction and scanning electron microscopy techniques. The deposit contains three layers at the bottom of the tube and two layers on the other sections and is composed of hydroxyapatite, calcium oxalate dihydrate and an amorphous material. The proportions of these phases varied along the tube height. Energy-dispersive spectroscopy and XRD analysis on the surfaces of the outermost and innermost layers showed that hydroxyapatite was the major phase attached to the tube wall, while calcium oxalate dihydrate (with pits and voids) was the major phase on the juice side. Elemental mapping of the cross-sections of the deposit revealed the presence of a mineral, Si-Mg-Al-Fe-O, which is probably a silicate mineral. Reasons for the defects in the oxalate crystal surfaces, the differences in the crystal size distribution from bottom to the top of the tube and the composite fouling process have been postulated.

Diarrhoea risk factors in enterally tube fed critically ill patients : a retrospective audit

Objective: Diarrhoea in the enterally tube fed (ETF) intensive care unit (ICU) patient is a multifactorial problem. Diarrhoeal aetiologies in this patient cohort remain debatable; however, the consequences of diarrhoea have been well established and include electrolyte imbalance, dehydration, bacterial translocation, peri anal wound contamination and sleep deprivation. This study examined the incidence of diarrhoea and explored factors contributing to the development of diarrhoea in the ETF, critically ill, adult patient. ---------- Method: After institutional ethical review and approval, a single centre medical chart audit was undertaken to examine the incidence of diarrhoea in ETF, critically ill patients. Retrospective, non-probability sequential sampling was used of all emergency admission adult ICU patients who met the inclusion/exclusion criteria. ---------- Results: Fifty patients were audited. Faecal frequency, consistency and quantity were considered important criteria in defining ETF diarrhoea. The incidence of diarrhoea was 78%. Total patient diarrhoea days (r = 0.422; p = 0.02) and total diarrhoea frequency (r = 0.313; p = 0.027) increased when the patient was ETF for longer periods of time. Increased severity of illness, peripheral oxygen saturation (Sp02), glucose control, albumin and white cell count were found to be statistically significant factors for the development of diarrhoea. ---------- Conclusion: Diarrhoea in ETF critically ill patients is multi-factorial. The early identification of diarrhoea risk factors and the development of a diarrhoea risk management algorithm is recommended.

Probiotics and diarrhoea management in enterally tube fed critically ill patients : what is the evidence?

Objective: The aim of this literature review is to identify the role of probiotics in the management of enteral tube feeding (ETF) diarrhoea in critically ill patients.---------- Background: Diarrhoea is a common gastrointestinal problem seen in ETF patients. The incidence of diarrhoea in tube fed patients varies from 2% to 68% across all patients. Despite extensive investigation, the pathogenesis surrounding ETF diarrhoea remains unclear. Evidence to support probiotics to manage ETF diarrhoea in critically ill patients remains sparse.---------- Method: Literature on ETF diarrhoea and probiotics in critically ill, adult patients was reviewed from 1980 to 2010. The Cochrane Library, Pubmed, Science Direct, Medline and the Cumulative Index of Nursing and Allied Health Literature (CINAHL) electronic databases were searched using specific inclusion/exclusion criteria. Key search terms used were: enteral nutrition, diarrhoea, critical illness, probiotics, probiotic species and randomised clinical control trial (RCT).---------- Results: Four RCT papers were identified with two reporting full studies, one reporting a pilot RCT and one conference abstract reporting an RCT pilot study. A trend towards a reduction in diarrhoea incidence was observed in the probiotic groups. However, mortality associated with probiotic use in some severely and critically ill patients must caution the clinician against its use.---------- Conclusion: Evidence to support probiotic use in the management of ETF diarrhoea in critically ill patients remains unclear. This paper argues that probiotics should not be administered to critically ill patients until further research has been conducted to examine the causal relationship between probiotics and mortality, irrespective of the patient's disease state or projected prophylactic benefit of probiotic administration.

Thermal profile of a near-adiabatic compression process in a cylindrical tube and establishment of critical control elements for repeatable process control

The compressed gas industry and government agencies worldwide utilize "adiabatic compression" testing for qualifying high-pressure valves, regulators, and other related flow control equipment for gaseous oxygen service. This test methodology is known by various terms including adiabatic compression testing, gaseous fluid impact testing, pneumatic impact testing, and BAM testing as the most common terms. The test methodology will be described in greater detail throughout this document but in summary it consists of pressurizing a test article (valve, regulator, etc.) with gaseous oxygen within 15 to 20 milliseconds (ms). Because the driven gas1 and the driving gas2 are rapidly compressed to the final test pressure at the inlet of the test article, they are rapidly heated by the sudden increase in pressure to sufficient temperatures (thermal energies) to sometimes result in ignition of the nonmetallic materials (seals and seats) used within the test article. In general, the more rapid the compression process the more "adiabatic" the pressure surge is presumed to be and the more like an isentropic process the pressure surge has been argued to simulate. Generally speaking, adiabatic compression is widely considered the most efficient ignition mechanism for directly kindling a nonmetallic material in gaseous oxygen and has been implicated in many fire investigations. Because of the ease of ignition of many nonmetallic materials by this heating mechanism, many industry standards prescribe this testing. However, the results between various laboratories conducting the testing have not always been consistent. Research into the test method indicated that the thermal profile achieved (i.e., temperature/time history of the gas) during adiabatic compression testing as required by the prevailing industry standards has not been fully modeled or empirically verified, although attempts have been made. This research evaluated the following questions: 1) Can the rapid compression process required by the industry standards be thermodynamically and fluid dynamically modeled so that predictions of the thermal profiles be made, 2) Can the thermal profiles produced by the rapid compression process be measured in order to validate the thermodynamic and fluid dynamic models; and, estimate the severity of the test, and, 3) Can controlling parameters be recommended so that new guidelines may be established for the industry standards to resolve inconsistencies between various test laboratories conducting tests according to the present standards?

A tan in a test tube -in vitro models for investigating ultraviolet radiation-induced damage in skin

Presently, global rates of skin cancers induced by ultraviolet radiation (UVR) exposure are on the rise. In view of this, current knowledge gaps in the biology of photocarcinogenesis and skin cancer progression urgently need to be addressed. One factor that has limited skin cancer research has been the need for a reproducible and physiologically-relevant model able to represent the complexity of human skin. This review outlines the main currently-used in vitro models of UVR-induced skin damage. This includes the use of conventional two-dimensional cell culture techniques and the major animal models that have been employed in photobiology and photocarcinogenesis research. Additionally, the progression towards the use of cultured skin explants and tissue-engineered skin constructs, and their utility as models of native skin's responses to UVR are described. The inherent advantages and disadvantages of these in vitro systems are also discussed.

Visualization of thermal characteristics around the absorber tube of a standard parabolic trough thermal collector by 3D simulation

Three dimensional conjugate heat transfer simulation of a standard parabolic trough thermal collector receiver is performed numerically in order to visualize and analyze the surface thermal characteristics. The computational model is developed in Ansys Fluent environment based on some simplified assumptions. Three test conditions are selected from the existing literature to verify the numerical model directly, and reasonably good agreement between the model and the test results confirms the reliability of the simulation. Solar radiation flux profile around the tube is also approximated from the literature. An in house macro is written to read the input solar flux as a heat flux wall boundary condition for the tube wall. The numerical results show that there is an abrupt variation in the resultant heat flux along the circumference of the receiver. Consequently, the temperature varies throughout the tube surface. The lower half of the horizontal receiver enjoys the maximum solar flux, and therefore, experiences the maximum temperature rise compared to the upper part with almost leveled temperature. Reasonable attributions and suggestions are made on this particular type of conjugate thermal system. The knowledge that gained so far from this study will be used to further the analysis and to design an efficient concentrator photovoltaic collector in near future.

Lateral impact response and parametric studies of axially loaded square concrete filled steel tube columns

This paper presents a numerical study on the response of axially loaded slender square concrete filled steel tube (CFST) columns under low velocity lateral impact loading. A finite element analysis (FEA) model was developed using the explicit dynamic nonlinear finite element code LS -DYNA in which the strain rate effects of both steel and concrete, contact between steel tube and concrete and confinement effect provided by the steel tube for the concrete were considered. The model also benefited from a relatively recent feature of LS-DYNA for applying a pre-loading in the explicit solver. The developed numerical model was verified for its accuracy and adequacy by comparing the results with experimental results available in the literature. The verified model was then employed to conduct a parametric study to investigate the influence of axial load level, impact location, support conditions, and slenderness ratio on the response of the CFST columns. A good agreement between the numerical and experimental results was achieved. The model could reasonably predict the impact load-deflection history and deformed shape of the column at the end of the impact event. The results of the parametric study showed that whilst impact location, axial load level and slenderness ratio can have a significant effect on the peak impact force, residual lateral deflection and maximum lateral deflection, the influence of support fixity is minimal. With an increase of axial load to up to a certain level, the peak force increases; however, a further increase in the axial load causes a decrease in the peak force. Both residual lateral deflection and maximum lateral deflection increase as axial load level increases. Shifting the impact location towards the supports increases the peak force and reduces both residual and maximum lateral deflections. A rise in slenderness ratio decreases the peak force and increases the residual and maximum lateral deflections.