SMaRT-PCR: sampling using masks and RT-PCR, a non-invasive diagnostic tool for paediatric pulmonary TB.

Key challenges in paediatric TB diagnosis are invasive sampling and poor sensitivity of standard methods. This study demonstrates the diagnostic potential of non-invasive sampling of bioaerosols from children using SMaRT-PCR, comprising mask sampling combined with reverse transcriptase-polymerase chain reaction (RT-PCR) for TB.Exhaled bioaerosols were captured on modified N-95 masks in a 10-min talk-cough-breathe process from 51 children (30 with TB confirmed using standard sampling methods and 21 without TB) aged 2-15 years. All mask samples were tested using in-house RT-PCR for 16s and rpoB RNA transcripts. Additional mask samples from children with TB were tested using Xpert® MTB/RIF (n = 3) and Xpert® MTB/RIF Ultra (n = 27).SMaRT-PCR sensitivity for detecting TB among treatment-naïve children was 96% if 16s or rpoB was present, and 75% if both genes were present, comparable to standard methods (71%) in the same cohort. Specificity was better for both genes, at 95%, than 85% for a single gene detection. Mask sampling with Xpert MTB/RIF or Ultra had a sensitivity of only 13%.This is the first study to provide evidence for testing bioaerosols as a promising alternative for detecting paediatric TB. Sampling is non-invasive and simple, with the potential for point-of-care applications. This pilot study also suggests that RNA transcript-based detection may improve TB diagnostic sensitivity in children; however, further investigation is required to establish its adaptability in clinical settings..

Observation of the binary coalescence and equilibration of micrometer-sized droplets of aqueous aerosol in a single-beam gradient-force optical trap.

The binary coalescence of aqueous droplets has been observed in a single-beam gradient-force optical trap. By measuring the time-dependent intensity for elastic scattering of light from the trapping laser, the dynamics of binary coalescence have been examined and the time scale for equilibration of a composite droplet to ambient conditions has been determined. These data are required for modeling the agglomeration of aqueous droplets in dense sprays and atmospheric aerosol. Elastic-light scattering from optically trapped particles has not been used previously to study the time-resolved dynamics of mixing. It is shown to offer a unique opportunity to characterize the binary coalescence of aqueous droplets with radii from 1 to 6 µm. The study of this size regime, which cannot be achieved by conventional imaging methods, is critical for understanding the interactions of droplets in the environment of dense sprays.

Case-control study of vitamin D status and adult multidrug-resistant pulmonary TB.

BACKGROUND: India has the highest prevalence of multidrug-resistant TB (MDR-TB) globally. Vitamin D deficiency is potentially an important risk factor for MDR-TB.METHODS: We conducted a case-control study of 90 newly diagnosed adult MDR-TB cases, 180 household controls and 82 non-household controls in Mumbai, India. Serum 25-hydroxyvitamin D (25(OH)D), anthropometry, clinical status and history, dietary data and sociodemographic data were collected from each participant. Interferon-gamma release assay (IGRA) was also performed in controls to assess latent TB. Multivariable regression was performed to estimate associations between 25(OH)D vs. case status and IGRA positivity.RESULTS: Mean participant age was 33.8 ± 12.0 years; 72.8% had 25(OH)D <20 ng/ml. Mean 25(OH)D was significantly (P < 0.05) lower in cases (12.5 ± 7.9) than both household (17.5 ± 11.2) and non-household controls (16.4 ± 9.1). In multivariable models, 25(OH)D concentration was inversely associated with MDR-TB case status among cases and household controls (OR 0.95 per 1 ng/ml, 95% CI 0.92-0.99; P = 0.015), and among cases and non-household controls (OR 0.94 per 1 ng/ml, 95% CI 0.89-1.00; P = 0.033); 53.6% of controls were IGRA-positive. 25(OH)D status was not associated with IGRA positivity.CONCLUSION: Vitamin D status was independently associated with MDR-TB case status. Research should evaluate the effectiveness of vitamin D supplementation in prevention and adjunctive treatment of MDR-TB.

Development and validation of a symptom questionnaire for recording outcomes in adult lacrimal surgery.

BACKGROUND: A symptom-based questionnaire (the `Lac-Q` questionnaire) for adult patients undergoing lacrimal drainage surgery was developed. The questionnaire yields a numerical score that can be used to assess severity of symptoms. METHODOLOGY: In this study, the questionnaire was evaluated in 17 consecutive patients undergoing 22 dacryocystorhinostomy (DCR) procedures. The questionnaire was administered pre- and postoperatively. The pathology encountered at operation was recorded. The success of surgery was judged by patient satisfaction, endoscopic evaluation of DCR stomal patency, and objective lacrimal drainage testing using the functional endoscopic dye test (FEDT). In a further group of 12 pre-operative cases, the questionnaire was repeated after 4-6 weeks but before surgery, to assess test-retest reliability in the absence of clinical change. RESULTS: The Lac-Q questionnaire was based on two broad categories of eye-specific scores and social impact scores. A numerical score, the `Lac-Q` score, was generated pre- and postoperatively. When compared to pre-operative scores, the reduction in Lac-Q scores postoperatively was significant. Postoperative scores also correlated well with objective lacrimal drainage testing using the FEDT. Analysis of symptom scores shows that the questionnaire was reliable with regard to content validity, internal consistency, test-retest reliability, and responsiveness to clinical change. CONCLUSIONS: We conclude that the Lac-Q questionnaire is a useful clinical tool to evaluate outcomes after adult lacrimal surgery.

Chest decompression during the resuscitation of patients in prehospital traumatic cardiac arrest.

BACKGROUND: Tension and bilateral pneumothorax can cause or contribute to death following trauma. A surgical incision (thoracostomy) or needle decompression through the chest wall rapidly treats these conditions. Resuscitation of patients in traumatic cardiac arrest focuses on treating common and reversible life-threatening conditions. A study was undertaken to observe the practice, findings and outcome of chest decompression when performed as part of the resuscitation strategy of these patients by air ambulance crews. METHODS: Patients in prehospital traumatic cardiac arrest were identified over a 39-month period from an air ambulance database. The use of thoracostomy or needle decompression was identified together with indications, findings and outcome. Primary outcome was return of cardiac output by arrival at hospital. RESULTS: 18 of 37 cases underwent chest decompression (17 thoracostomy, 1 needle decompression). Four patients had a return of cardiac output (3 tension pneumothorax, 1 bilateral pneumothorax). Six further cases were positive for intrathoracic injury. In 2 cases the injuries identified were incompatible with life and resuscitation efforts were consequently ceased. CONCLUSIONS: Chest decompression in traumatic cardiac arrest identifies and treats a high proportion of potentially life-ending injuries and should be considered as part of the resuscitation effort of patients in traumatic cardiac arrest. In a proportion of patients, non-survivable injuries are identified which guide resuscitation efforts.

A resistant case of spontaneous intracranial hypotension.

The case of a 39-year-old with intractable spontaneous intracranial hypotension (SIH) is presented. He developed bilateral and symptomatic subdural hygromas that were drained in response to clinical deterioration, but proved ineffective. An initial MRI of the lumbar region suggested a lumbosacral CSF leak, but he failed to respond to local blood patching. Subsequent CT myelography revealed a thoracic dural leak and a second directed blood patch proved effective. The aetiology, pitfalls and management of SIH are summarized.

Observations on categorisation of new TB cases: implications for controlling drug resistance.

In the context of rising rates of drug-resistant tuberculosis (TB) in India, this communication presents some field observations during screening of new cases registered with the Revised National Tuberculosis Control Programme (RNTCP) in urban and rural areas of Maharashtra, India. It appears that erroneous categorisation and treatment that contributes to multiple drug resistance results from a lack of patient screening for previous treatment, ambiguity in categorisation and reluctance to disclose a history of anti-tuberculosis treatment. Suggested measures include detailed screening of new cases, computerisation of patient records and an empathetic dialogue between patient and health care provider.

endoscope-i: an innovation in mobile endoscopic technology transforming the delivery of patient care in otolaryngology.

INTRODUCTION: Digital and mobile device technology in healthcare is a growing market. The introduction of the endoscope-i, the world's first endoscopic mobile imaging system, allows the acquisition of high definition images of the ear, nose and throat (ENT). The system combines the e-i Pro camera app with a bespoke engineered endoscope-i adaptor which fits securely onto the iPhone or iPod touch. Endoscopic examination forms a salient aspect of the ENT work-up. The endoscope-i therefore provides a mobile and compact alternative to the existing bulky endoscopic systems currently in use which often restrict the clinician to the clinic setting. Areas covered: This article gives a detailed overview of the endoscope-i system together with its applications. A review and comparison of alternative devices on the market offering smartphone adapted endoscopic viewing systems is also presented. Expert commentary: The endoscope-i fulfils unmet needs by providing a compact, highly portable, simple to use endoscopic viewing system which is cost-effective and which makes use of smartphone technology most clinicians have in their pocket. The system allows real-time feedback to the patient and has the potential to transform the way that healthcare is delivered in ENT as well as having applications further afield.

Rhodococcus and Mycobacterium Tuberculosis: masquerade or mixed infection.

Rhodocci have a morphology similar to that of Mycobacterium tuberculosis (TB), and are indistinguishable from normal diphtheroid flora. Symptoms include fever, productive/non-productive cough and pleuritic chest pain. Rhodococcal infections, being resistant to routine anti-tuberculosis medications, may be misdiagnosed as drug-resistant TB, thus prompting treatment for TB with rifampicin-containing regimens that promote the emergence of resistance. We present here a sputum smear AFB-positive case who, although clinically cured, remains unresolved despite a series of technological investigations as to the cause of infection being purely rhodococci or mixed infection with M. tuberculosis.

Acute unilateral sensorineural hearing loss associated with anabolic steroids and polycythaemia: case report.

BACKGROUND: Unilateral sudden sensorineural hearing loss due to an infarct in the vertebrobasilar system has been widely reported. Most patients have a background of traditional coronary risk factors related to these cerebrovascular episodes. CASE REPORT: A 32-year-old male, a regular user of anabolic steroids, presented to the emergency department with unilateral sensorineural hearing loss and symptoms suggestive of an infarct of the anterior inferior cerebellar artery but in the absence of risk factors for ischaemic stroke. RESULTS: Magnetic resonance imaging confirmed the presence of infarction in the region supplied by the anterior inferior cerebellar artery. Polycythaemia was found on haematological analysis, which we believe was secondary to the use of anabolic steroids. The patient was commenced on aspirin as per the stroke management protocol. There was resolution of neurological symptomatology six weeks after the episode, but no improvement in hearing. CONCLUSION: To our knowledge, this is the first case report of unilateral sensorineural hearing loss secondary to the use of anabolic steroids causing polycythaemia. This cause should be considered in the differential diagnosis of patients presenting with sensorineural hearing loss, especially in young males, when no other risk factors can be identified.

Platelets and the injured vessel wall-- "rolling into action": focus on glycoprotein Ib/V/IX and the platelet cytoskeleton.

Blood platelets play a key role in maintaining the integrity of the vascular system through their ability to arrest bleeding (haemostasis) and promote repair of injured blood vessels. Considerable progress has been made in the last few years in our understanding of the adhesion mechanisms utilized by platelets to adhere to sites of vascular injury. Studies have helped define the precise role of von Willebrand factor (vWf), and its platelet receptor, glycoprotein (GP) Ib/V/IX, in initiating platelet-vessel wall and platelet-platelet adhesion contacts. In addition to its adhesive role, recent studies have highlighted the importance of GPIb/V/IX in regulating the cytoskeleton of platelets. GPIb/V/IX not only maintains the normal cytoskeletal architecture of resting platelets but also induces cytoskeletal reorganization following engagement of vWf. Somewhat surprisingly, the physical link between GPIb/V/IX and the membrane skeleton does not appear necessary for GPIb/V/IX-induced cytoskeletal reorganization. In contrast, this linkage appears critical for GPIb/V/IX to maintain cell adhesion under high shear and also for the ability of the cytoskeleton to exert negative regulatory effects on the GPIb-vWf interaction. Thus a complex functional relationship appears to exist between GPIb/V/IX and the membrane skeleton that goes well beyond preserving the normal cytoskeletal architecture of resting platelets.

Mineralocorticoids and mineralocorticoid receptors in mononuclear leukocytes in patients with pregnancy-induced hypertension.

To examine the role of mineralocorticoids in the pathophysiology of pregnancy-induced hypertension (PIH), we studied plasma aldosterone and 18-hydroxycorticosterone levels in 25 women with PIH and 25 normal pregnant women, as controls. Furthermore, we evaluated the mineralocorticoid receptor (MR) status in mononuclear leukocytes in the 2 groups. MR count was significantly (P less than 0.0005) decreased in the PIH group (148 +/- 9 binding sites/cell) compared with the control group (300 +/- 17 binding sites/cell; mean +/- SEM). Plasma aldosterone in women with PIH was 281 +/- 61 pmol/L; in normal pregnant women it was 697 +/- 172 pmol/L (P less than 0.025). Plasma 18-hydroxycorticosterone was also significantly (P less than 0.025) lower (PIH, 1071 +/- 149 pmol/L; controls, 1907 +/- 318 pmol/L). These values were determined at the onset of clinical symptoms of PIH. These results cannot be explained by receptor down-regulation due to higher levels of mineralocorticoids in PIH; a hitherto unknown mineralocorticoid may, thus, be responsible for the hypertension and altered MR status.

Immunogenicity of DNA damaged by reactive oxygen species--implications for anti-DNA antibodies in lupus.

Reactive oxygen species (ROS) are implicated in the inflammatory, autoimmune, connective tissue disease, systemic lupus erythematosus (SLE), particularly in respect of processes leading to the formation of pathological anti-DNA antibodies. Exposure to ROS increases the antigenicity of DNA for SLE antibodies, but data on the immunogenicity of ROS-DNA are not conclusive. In this study, we have examined the immunogenicity in rabbits, of DNA modified by three hydroxyl radical generating systems. Additionally, we investigated the antigenicity of UVA, UVB, and UVC irradiated DNA for lupus anti-DNA antibodies. Modification of DNA by both ROS and far UV dramatically increased its immunogenicity; the Fe2+ and H2O2 system resulted in antibodies that recognized both native and modified DNA. In our ELISA system, none of the UV antigens showed any antigenicity above native DNA for SLE sera. The data suggested that different profiles of antigenicity and immunogenicity arise dependent on the method of ROS production, but also that ROS-DNA may be a factor in antigen-driven immune complex formation in SLE.

Immunochemical detection of glyoxal DNA damage.

The relevance of reactive oxygen species (ROS) in the pathogenesis of inflammatory diseases is widely documented. Immunochemical detection of ROS DNA adducts has been developed, however, recognition of glyoxal-DNA adducts has not previously been described. We have generated a polyclonal antibody that has shown increased antibody binding to ROS-modified DNA in comparison to native DNA. In addition, dose-dependent antibody binding to DNA modified with ascorbate alone was shown, with significant inhibition by desferrioxamine, catalase, and ethanol. Minimal inhibition was observed with uric acid, 1,10-phenanthroline and DMSO. However, antibody binding in the presence of EDTA increased 3500-fold. The involvement of hydrogen peroxide and hydroxyl radical in ascorbate-mediated DNA damage is consistent with ascorbate acting as a reducing agent for DNA-bound metal ions. Glyoxal is known to be formed during oxidation of ascorbate. Glyoxylated DNA, that previously had been proposed as a marker of oxidative damage, was recognised in a dose dependent manner using the antibody. We describe the potential use of our anti-ROS DNA antibody, that detects predominantly Fenton-type mediated damage to DNA and report on its specificity for the recognition of glyoxal-DNA adducts.

A novel HPLC procedure for the analysis of 8-oxoguanine in DNA.

The chromatographic quantitation of 8-oxoguanine adducts in DNA is widespread in the literature, although results obtained by HPLC of 8-oxodeoxyguanosine do not always agree with levels determined by GC-MS. To help explain this discrepancy, here we describe a novel procedure for the analysis of 8-oxoguanine adducts in DNA. Although it proved difficult to directly quantitate 8-oxoguanine in the presence of high levels of endogenous guanine using conventional reversed-phase HPLC, a simple preincubation of DNA acid hydrolysates with guanase allowed such analyses. The assay relied on our observation that 8-oxoguanine was not a substrate for guanase, and on sensitive electrochemical detection. The limit of detection for 8-oxoguanine was 5 nM or 250 fmol on column. Using this procedure, the background level of 8-oxoguanine in commercially available calf thymus DNA was 0.4 nmol/mg DNA or 3.2 mol/10(5) mol guanine.

Novel repair action of vitamin C upon in vivo oxidative DNA damage.

There appears to be a paucity of data examining the effect of dietary antioxidants on levels of oxidative DNA damage in vivo, limiting evidence-based assessment of antioxidant efficacy, mechanisms and recommendation for optimal intake. We have examined levels of 8-oxo-2'-deoxyguanosine (8-oxodG) in mononuclear cell DNA, serum and urine from subjects undergoing supplementation with 500 mg/day vitamin C. Significant decreases in DNA levels of 8-oxodG were seen, correlating strongly with increases in plasma vitamin C concentration. Furthermore we established a timecourse for sequential, significant increases in serum and urinary 8-oxodG levels. These results illustrate, for the first time in humans, the kinetics of 8-oxodG removal and processing in vivo, suggesting a role for vitamin C in the regulation of DNA repair enzymes and thereby demonstrating a non-scavenging antioxidant effect.