The effects of N-acetylcysteine on lung alveolar epithelial cells infected with respiratory syncytial virus.

INTRODUCTION: Respiratory syncytial virus (RSV) is one of the most common causes of acute lower respiratory infection in infants and young children. Mucolytic agents, such as acetylcysteine and carbocysteine have reported benefits in alleviating acute upper or lower respiratory infections. Among these, N-acetylcysteine (NAC) has cyto-protective effects when cells are infected with the RSV. MATERIALS AND METHODS: Our study investigated primarily the dose-dependent effects of NAC on respiratory alveolar epithelial (A549) cells when co-cultured with RSV in vitro. Three different concentrations of NAC were used, 0.1 mM, 1 mM, and 10 mM. The cytotoxicity of RSV-infected cells was measured by lactate dehydrogenase and antiviral activity of NAC on cell cultures was evaluated by immunofluorescence. RESULTS: Pre-treatment with the highest dose, 10 mM NAC, resulted in features of cell injury even without RSV infection. The proportion of cells infected by RSV and RSV-induced cell death decreased by more than 3-fold when cells were pre-treated with 1 mM NAC. Pre-treatment at the lowest dose, 0.1 mM, did not show any significant changes. CONCLUSION: A moderate dose of NAC (1 mM) appeared protective of RSV infection to lung alveolar epithelial cells. However, a higher dose of NAC (10 mM) may be relatively toxic and injurious to these cells.

Optical Kerr effect and third harmonic generation in topological Dirac/Weyl semimetal.

We study the nonlinear optical response generated by the massless Dirac quasiparticles residing around the topologically-protected Dirac/Weyl nodal points in three-dimensional (3D) topological semimetals. Analytical expressions of third-order interband nonlinear optical conductivities are obtained based on a quantum mechanical formalism which couples 3D Dirac fermions with multiple photons. Our results reveal that the massless Dirac fermions in three dimensions retains strong optical nonlinearity in terahertz frequency regime similar to the case of the two-dimensional Dirac fermions in graphene. At room temperature, the Kerr nonlinear refractive index and the harmonic generation susceptibility are found to be n2 = 10-11 ∼ 10-8 m2W-1 and χ(3) = 10-14 ∼ 10-8 m2V-2, respectively, in the few terahertz frequency regimes, which is comparable to graphene and orders of magnitudes stronger than many nonlinear crystals. Importantly, because 3D topological Dirac/Weyl semimetals possess bulk structural advantage not found in the strictly two-dimensional graphene, greater design flexibility and improved ease-of-fabrication in terms of photonic and optoelectronic device applications can be achieved. Our finding reveals the potential of 3D topological semimetals as a viable alternative to graphene for nonlinear optics applications.

Wavelength selective mode division multiplexing on a silicon chip.

Multiplexing of optical modes in waveguides is demonstrated using coupled vertical gratings. The device utilizes sinusoidally corrugated waveguides of different widths with a period designed to multiplex information at 1.55 µm. The design, fabrication and characterization of devices is performed. Multiplexing of modes is demonstrated in optical structures which support 3 and 5 quasi-TE modes. The design utilizes counter-propagating modes in periodic structures, thus enabling the device to combine its mode division multiplexing capabilities with wavelength division multiplexing functionalities to further augment the multiplexing capacity of the device.

Terahertz spectroscopy of the reactive and radiative near-field zones of split ring resonator.

A terahertz microscope has been used to excite and observe the resonant modes of a single split ring resonator in the reactive and radiative near-field zones. The two lowest resonant modes of an isolated split ring resonator with their corresponding radiation patterns are reported; they showed good agreement to simulations. The passage from the reactive to radiative near-field zone is also discussed. Further, our result introduced a novel technique to perform terahertz time-domain spectroscopy of samples a few tens of micrometers in size by measuring the in-plane radiative near-field zone.

Plasmonic coupled-cavity system for enhancement of surface plasmon localization in plasmonic detectors.

A plasmonic coupled-cavity system, which consists of a quarter-wave coupler cavity, a resonant Fabry-Pérot detector nanocavity, and an off-resonant reflector cavity, is used to enhance the localization of surface plasmons in a plasmonic detector. The coupler cavity is designed based on transmission line theory and wavelength scaling rules in the optical regime, while the reflector cavity is derived from off-resonant resonator structures to attenuate transmission of plasmonic waves. We observed strong coupling of the cavities in simulation results, with an 86% improvement of surface plasmon localization achieved. The plasmonic coupled-cavity system may find useful applications in areas of nanoscale photodetectors, sensors, and an assortment of plasmonic-circuit devices.

Current practice in preoperative therapy and surgical management of locally advanced rectal cancer: a bi-national survey.

AIM: The Australasian colorectal surgeon's current approach to preoperative rectal cancer management was compared with international guidelines. METHOD: Members of the Colorectal Surgical Society of Australia and New Zealand were surveyed in 2010, on the use of MRI and the management of locally advanced rectal cancer. Surgeons had to decide the appropriate management in five scenarios that were developed from national guidelines. RESULTS: Of 174 invitations sent, 108 (62.1%) replies were received. Most surgeons (98.1%) had access to MRI. Ninety-three (86.1%) would use MRI routinely for staging. The majority selected a tumour-specific mesorectal resection for upper rectal cancer (58.2%) and a total mesorectal excision for distal cancer (100%). Almost all restorative operations included a covering ileostomy. One third of surgeons recommended that patients with a favourable cT3 mid-rectal tumour (N0, clear circumferential resection margins) should not have preoperative therapy and should proceed directly to surgery. When high-risk features, such as threatened resection margins or cN1 stage, were present, 5% and 15% of surgeons, respectively, would continue to treat by standard resection without preoperative therapy. CONCLUSION: Evidence-based international guidelines for the management of rectal cancer have changed little in the last 10 years. Despite this, there is a clear gap between these and clinical practice. The main variance relates to the role of radiotherapy in locally advanced rectal cancer. Despite considerable evidence that radiotherapy reduces local recurrence for all stages of rectal cancer, current practice in Australasia is for its selective use.

Managing fistula-in-ano with ligation of the intersphincteric fistula tract procedure: the Western Hospital experience.

AIM: To review the preliminary results of the ligation of the intersphincteric fistula tract (LIFT) technique in treating complex anal fistulas at our hospital. METHOD: Between March and November 2010, patients with cryptoglandular anal fistulas were recruited prospectively from the colorectal clinic and treated using the LIFT procedure. A database was set up to collect information on demographics, past surgical treatments, fistula characteristics, MRI scan results, operative data and follow-up findings. The primary end-point measured was cure of the disease. The secondary end-point was the degree of postoperative continence. Preoperative and postoperative incontinence rates were recorded using Wexner's Incontinence Scale. RESULTS: Twenty-five patients (eight women and 17 men; median age, 40 years) underwent the LIFT procedure. Ten patients had recurrent fistulas and previous fistula surgery. The median operating time was 39 min. No intraoperative complications were documented. The median follow-up duration was 22 (3-43) weeks. Primary healing was observed in 17 (68.0%) patients and the median healing time was 6 weeks; one wound remained incompletely healed. Seven patients (28.0%) had disease recurrence presenting between 7 and 20 weeks postoperatively. No patients reported any incontinence postoperatively. CONCLUSION: The LIFT procedure has favourable healing rates with little or no risk of incontinence. This operation is safe and easy to learn. The early results from this pilot study show promise and affirm some of the findings of other researchers. These results will suggest opportunities to conduct further controlled studies comparing the LIFT procedure with standard therapies.

Adsorption, desorption and mobility of metsulfuron-methyl in soils of the oil palm agroecosystem in Malaysia.

Laboratory experiments were conducted to evaluate adsorption, desorption and mobility of metsulfuron-methyl in soils of the oil palm agroecosystem consisting of the Bernam, Selangor, Rengam and Bongor soil series. The lowest adsorption of metsulfuron-methyl occurred in the Bongor soil (0.366 ml g(-1)), and the highest in the Bemam soil (2.837 ml g(-1). The K(fads) (Freundlich) values of metsulfuron-methyl were 0.366, 0.560, 1.570 and 2.837 ml g(-1) in Bongor, Rengam, Selangor and Bemam soil, respectively. The highest K(fdes) value of metsulfuron-methyl, observed in the Bemam soil, was 2.563 indicating low desorption 0.280 (relatively strong retention). In contrast, the lowest K(fdes) value of 0.564 was observed for the Bongor soil, which had the lowest organic matter (1.43%) and clay content (13.2%). Soil organic matter and clay content were the main factors affecting the adsorption of metsulfuron-methyl. The results of the soil column leaching studies suggested that metsulfuron-methyl has a moderate potential for mobility in the Bernam and Bongor soil series with 19.3% and 39%, respectively for rainfall at 200 mm. However, since metsulfuron-methyl is applied at a very low rate (the maximum field application rate used was 30 g ha(-1)) and is susceptible to biodegradation, the potential forground water contamination is low.

Body Weight Loss After Orthognathic Surgery: Comparison Between Postoperative Intermaxillary Fixation with Metal Wire and Elastic Traction, Factors Related to Body Weight Loss.

INTRODUCTION: The aim of this study was to compare body weight loss between postoperative intermaxillary fixation with metal wire and elastic traction and to investigate factors related to body weight loss after orthognathic surgery. MATERIALS AND METHODS: Subjects were 59 patients with dentofacial deformity, comprising 31 patients treated with intermaxillary fixation (IMF) and 28 patients treated with elastic traction without IMF (ELT) just after surgery. Body weight loss was measured at 1 week (T1) and 2 weeks (T2) after surgery. Body weight loss was compared between IMF and ELT, and factors related to body weight loss were statistically analyzed. RESULTS: Body weight loss ratio was significantly increased in IMF (2.6%) rather than in ELT (1.4%) at T1, but only tended to be increased in both groups at T2, showing no statistical difference. Body weight loss ratio was significantly increased at T2 compared to T1 in both groups. Body weight loss was significantly greater at T2 than at T1. CONCLUSION: Both IMF and ELT cause body weight loss after orthognathic surgery, but IMF causes body weight loss earlier than ELT and increased early body weight loss increases continuous body weight loss after orthognathic surgery.

Molecular mechanism of kallikrein-related peptidase 8/neuropsin-induced hyperkeratosis in inflamed skin.

BACKGROUND: Hyperkeratosis and acanthosis occur in inflamed skin. Proliferation and differentiation of keratinocytes are important processes during epidermal repair after inflammation. Neuropsin and its human homologue kallikrein-related peptidase 8 (KLK8) have been reported to be involved in epidermal proliferation and differentiation, but the involved molecular mechanisms are obscure. OBJECTIVES: To explore the molecular mechanism of KLK8/neuropsin-induced hyperkeratosis and acanthosis in inflamed skin. METHODS: The molecular mechanism involved in KLK8/neuropsin-induced hyperkeratosis and acanthosis in inflamed skin was investigated both in vivo and in vitro using neuropsin knockout mice and KLK8 knockdown human keratinocytes. Neuropsin-related genes were identified by differential gene display. The localization and functional relationship of the molecules affected downstream of KLK8/neuropsin in normal and inflamed skin were analysed by in situ hybridization and immunohistochemistry. RESULTS: Hyperkeratosis and acanthosis in sodium lauryl sulphate-stimulated skin were markedly inhibited in neuropsin knockout mice. Knockdown of KLK8/neuropsin increased transcription factor activator protein-2α (AP-2α) expression and decreased keratin 10 expression in human keratinocytes and mouse skin, respectively. AP-2α has been reported to inhibit epidermal proliferation and keratin 10 expression. Distributional analysis showed that KLK8/neuropsin was expressed in the stratum spinosum, AP-2α was expressed in the stratum basale and the lower part of the stratum spinosum, and keratin 10 was expressed throughout the stratum spinosum. CONCLUSIONS: The above findings suggest the following mechanism of events underlying KLK8/neuropsin-induced hyperkeratosis: (i) skin inflammation increases KLK8/neuropsin expression in the stratum spinosum; (ii) the released KLK8/neuropsin inhibits AP-2α expression in the cells of the stratum basale and stratum spinosum; (iii) the decrease in AP-2α results in cell proliferation in the stratum basale and cell differentiation in the stratum spinosum, with an increase in keratin 10 expression.

Relations between anterior disc displacement and maxillomandibular morphology in skeletal anterior open bite with changes to the mandibular condyle.

In this study we investigated the relation between anterior disc displacement (ADD) and maxillomandibular morphology in skeletal anterior open bite with changes to the mandibular condyle. Thirty female patients (60 joints) with both conditions were evaluated. Magnetic resonance imaging of the temporomandibular joint (TMJ) was used to diagnose both ADD and changes to the mandibular condyle (erosion, osteophyte, and deformity). The relations among ADD, changes to the mandibular condyle, and maxillomandibular morphology were examined statistically. Changes to the mandibular condyle had a higher score than sym anterior open bite, the deviated side in asymmetric anterior open bite, and the non-deviated side. The score for disc displacement on the non-deviated side was lower than both the sym side and the deviated side. Unilateral changes to the mandibular condyle and unilateral disc displacement were not apparent in sym anterior open bite, but a unilateral non-displaced disc was seen only on the asymmetric side. Mandibular condylar changes were significantly more common on the deviated, than on the non-deviated, side. The SNB angle was significantly smaller, and the ANB, GZN, and SN-mandibular plane angles were significantly larger in sym anterior open bite. Overjet, ANB angle, GZN angle, and SN-MP angle were significantly larger, and the SNB angle was significantly smaller, in the presence of ADD without reduction and mandibular condylar deformity. We conclude that the prevalence of ADD without reduction and changes to the mandibular condyle were related to mandibular asymmetry and mandibular morphology in anterior open bite. This retrospective study suggests that ADD without reduction and mandibular condylar bone changes may be related to the progression of skeletal class II open bite and mandibular asymmetry in cases of skeletal open bite.

Enhanced biological phosphorus removal in the retrofitting from an anoxic selector to an anaerobic selector in a full-scale activated sludge process in Singapore.

This paper presents the investigation results of retrofitting an anoxic selector to an anaerobic selector through stepwise reduction of air supply in a full-scale activated sludge process with a focus on enhanced biological phosphorus removal (EBPR). The process experienced gradual shift from a Ludzack-Ettinger (LE) to an anaerobic-anoxic-oxic (A(2)O) process and subsequently, an anaerobic-oxic (A/O) process. The major findings are: (i) the average influent-based PO(4) (3-)-P release in the anaerobic selector compartment was 16.3 mg P l(-1) and that in the secondary clarifier was 1.7 mg P l(-1). 75% of the SCOD and 93% of the acetic acid in the primary effluent were taken up in the anaerobic selector compartment, respectively; (ii) PO(4) (3-)-P uptake contributed by both aerobic and denitrifying phosphorus accumulating organisms (DPAOs) occurred mainly in the first and second aerobic lanes together with simultaneous nitrification and denitrification (SND) while there was not much contribution from the last aerobic lane; (iii) The average PO(4) (3-)-P concentration of the final effluent was 2.4 mg P l(-1) corresponding to a removal efficiency of 85%; (iv) the SVI was satisfactory after retrofitting; and (v) the increase of NH(4) (+)-N in the final effluent from the commencement to the completion of the retrofitting resulted in an approximate 40-50% reduction in oxygen demand and a significant aeration energy saving was achieved.

Familial Congenital Methemoglobinemia in Pomeranian Dogs Caused by a Missense Variant in the NADH-Cytochrome B5 Reductase Gene.

BACKGROUND: In veterinary medicine, congenital methemoglobinemia associated with nicotinamide adenine dinucleotide (NADH)-cytochrome b5 reductase (b5R) deficiency is rare. It has been reported in several breeds of dogs, but little information is available about its etiology. OBJECTIVES: To analyze the NADH-cytochrome b5 reductase gene, CYB5R3, in a Pomeranian dog family with methemoglobinemia suspected to be caused by congenital b5R deficiency. ANIMALS: Three Pomeranian dogs from a family with methemoglobinemia were analyzed. Five healthy beagles and 5 nonrelated Pomeranian dogs without methemoglobinemia were used as controls. METHODS: Methemoglobin concentration, b5R activity, and reduced glutathione (GSH) concentration were measured, and a turbidity index was used to evaluate Heinz body formation. The CYB5R3 genes of the affected dog and healthy dogs were analyzed by direct sequencing. RESULTS: Methemoglobin concentrations in erythrocytes of the affected dogs were remarkably higher than those of the control dogs. The b5R activity of the affected dogs was notably lower than that of the control dogs. DNA sequencing indicated that this Pomeranian family carried a CYB5R3 gene missense variant (ATC→CTC at codon 194) that resulted in the replacement of isoleucine (Ile) by leucine (Leu). CONCLUSIONS AND CLINICAL IMPORTANCE: This dog family had familial congenital methemoglobinemia caused by b5R deficiency, which resulted from a nonsynonymous variant in the CYB5R3 gene. This variation (c.580A>C) led to an amino acid substitution (p.Ile194Leu), and Ile194 was located in the proximal region of the NADH-binding motif. Our data suggested that this variant in the canine CYB5R3 gene would affect function of the b5R in erythrocytes.

Incidence of anterior disc displacement without reduction of the temporomandibular joint in patients with dentofacial deformity.

The aim of this study was to investigate the incidence of anterior disc displacement without reduction (ADDwoR) of the temporomandibular joint (TMJ) in patients with dentofacial deformity. Eighty-eight female patients (176 joints) with skeletal class III malocclusion and 33 female patients (66 joints) with skeletal class II malocclusion, with or without anterior open bite and asymmetry, were evaluated. Magnetic resonance imaging (MRI) of the TMJ was used to diagnose ADDwoR. A statistical analysis was performed to examine the relationship between ADDwoR and skeletal structure. ADDwoR was present in 37 of the 66 joints (56.1%) in class II compared to 34 of the 176 joints (19.3%) in class III (P<0.05). In class III, ADDwoR was significantly more common in joints with mandibular asymmetry (24/74; 32.4%) than in joints with open bite (9/62; 14.5%) and joints with open bite and without mandibular asymmetry (1/38; 2.6%). In class II, ADDwoR was significantly less common in joints with mandibular asymmetry and without open bite (1/8; 12.5%). ADDwoR was only observed on the deviated side in both class III and class II with mandibular asymmetry. The prevalence of ADDwoR differed according to the dentofacial morphology.

Pushing the limits of CMOS optical parametric amplifiers with USRN:Si7N3 above the two-photon absorption edge.

CMOS platforms operating at the telecommunications wavelength either reside within the highly dissipative two-photon regime in silicon-based optical devices, or possess small nonlinearities. Bandgap engineering of non-stoichiometric silicon nitride using state-of-the-art fabrication techniques has led to our development of USRN (ultra-silicon-rich nitride) in the form of Si7N3, that possesses a high Kerr nonlinearity (2.8 × 10-13 cm2 W-1), an order of magnitude larger than that in stoichiometric silicon nitride. Here we experimentally demonstrate high-gain optical parametric amplification using USRN, which is compositionally tailored such that the 1,550 nm wavelength resides above the two-photon absorption edge, while still possessing large nonlinearities. Optical parametric gain of 42.5 dB, as well as cascaded four-wave mixing with gain down to the third idler is observed and attributed to the high photon efficiency achieved through operating above the two-photon absorption edge, representing one of the largest optical parametric gains to date on a CMOS platform.

Dengue Fever-Associated Maculopathy and Panuveitis in Australia.

Purpose. To describe a case of dengue fever-associated maculopathy and panuveitis to raise awareness of these ophthalmic complications of dengue in Australia in the light of recent increasing numbers of outbreaks from equatorial through to tropical Australia. Case Report. A 37-year-old Caucasian Australian male returning from Cambodia presented with a bilateral dengue fever-associated maculopathy with left panuveitis diagnosed clinically and haematologically. Automated perimetry revealed bilateral paracentral scotomas while optical coherence tomography demonstrated the maculopathies to be of the diffuse retinal thickening type in the right eye and acute macular neuroretinopathy (AMN) type in the left eye. He was treated conservatively with only topical steroids and cycloplegia and made a full clinical visual recovery. Conclusion. Our case study underscores the importance of the awareness of the ophthalmic complications of dengue fever as despite their rarity they can be potentially sight threatening. The incidence of these complications is likely to rise in Australia with increased global warming and the distribution of Aedes aegypti into subtropical Australia.

ANCA associated pauci-immune retinal vasculitis.

BACKGROUND: Antinuclear cytoplasmic antibodies (ANCA) are useful diagnostic serological markers for the most common forms of necrotising vasculitis. ANCA associated vasculitides represent distinctive clinicopathological categories--for example, Wegener's granulomatosis, Churg-Strauss syndrome, microscopic polyangiitis, and idiopathic necrotising crescentic glomerulonephritis, collectively known as the small vessel pauci-immune vasculitides. METHOD: Three cases of ANCA associated pauci-immune retinal vasculitis are described. Their systemic features are described and the clinical significance of ANCA as a diagnostic test in relation to retinal vasculitis discussed. RESULTS: These three cases represent a spectrum of clinical features associated with retinal vasculitis. Two cases have evolved into clinical recognisable entities as microscopic polyangiitis. Adherence to the international consensus statement on testing and reporting of ANCA is recommended and the authors speculate that the incidence of microscopic polyangiitis may be underestimated because of the under-recognition of systemic involvement in patients with retinal vasculitis. CONCLUSION: The receipt of a positive ANCA result should always raise the suspicion of a pauci-immune systemic vasculitis and prompt appropriate investigation. The authors emphasise the importance of the evaluation of systemic features in these patients with retinal vasculitis, enabling earlier recognition and thereby preventing significant morbidity and mortality.

Ceroid granulomas in the female genital system.

Three cases of ceroid granulomas of the female genital system are presented, involving the cervix in two and lesions in the ovaries and bowel serosa in the other. Ceroid granulomas are unusual and interesting lesions formed when suitable substrates accumulate within macrophages to such an extent that a relative lack of biological antioxidants results and auto-oxidation and conversion to ceroid is favoured. This may occur in the setting of haemorrhage and necrosis, whether from tumour necrosis or associated with endometriosis. Other sources of lipids and lipoproteins include bile, meconium and vernix caseosa.

Molecular evolution of a host-range gene in geminiviruses infecting asexual populations of Eupatorium makinoi.

Asexual plants of Eupatorium makinoi is frequently infected with tobacco leaf curl geminivirus (TLCV). The host range of TLCV is narrow, and ORF C4 is considered to function as a host range determinant. Using this TLCV-Eupatorium system, we tested the expectation that the rate of amino acid replacements will be accelerated in ORF C4 if resistant genes of the host plants drive molecular evolution in ORF C4. ORF C4 is entirely contained within a longer ORF C1 encoding a replication protein. We analyzed 21 sequences containing ORF C4 and a part of ORF C1. While per-site number of synonymous substitutions exceeded that of replacements in ORF C1, per-site number of replacements exceeded that of synonymous substitutions in ORF C4. However, this excess of per-site replacement in ORF C4 was mostly explained by the overlap gene nature, because most synonymous substitutions in ORF C1 change amino acid of ORF C4. In conclusion, not positive but negative selection is a predominant mode characterizing molecular evolution of ORF C4.

Intravascular endometrial tissue in an ovary of a patient with abnormal endometrial histology.

A case of ovarian intravascular endometrial tissue in a 46 yr old woman with a strong family history of endometrial carcinoma and abnormal endometrial histology is presented. The diagnosis was supported by histological and immunohistochemical findings. Although recognized at other sites, intravascular endometrial tissue has not been described previously in the ovary.