High risk of Mycobacterium tuberculosis infection during the Hajj pilgrimage

INTRODUCTION: Annually more than 2 million pilgrims from all over the world attend the Hajj in Saudi Arabia. Overcrowding during this pilgrimage leads to a high risk of transmission of airborne infectious diseases. Tuberculosis (TB) is common among hospitalized pilgrims, but the overall risk of acquiring Mycobacterium tuberculosis infection during this pilgrimage is not known. We conducted a prospective study to assess the risk of M. tuberculosis infection among Hajj pilgrims. METHODS: We measured the immune response to TB antigens using a whole-blood assay (QuantiFERON TB assay) prior to departure and 3 months after return from the Hajj pilgrimage. RESULTS: Of 357 paired assays, 149 pilgrims were negative prior to the Hajj and 15 (10%) of these had a significant rise in immune response to TB antigens. CONCLUSIONS: Pilgrims may be at high risk of acquiring M. tuberculosis infection during the Hajj. This has significant public health implications for TB control in countries with large Muslim populations.     

Outcome following radiotherapy for loco-regionally recurrent non-small cell lung cancer

Local and regional recurrence of non-small cell lung cancer is reported to occur in 13-20% of treatment failures after resection. Reported post-recurrent median survival following radiotherapy ranges from 9 to 14 months. This study examines survival following radiotherapy alone for patients with loco-regionally recurring non-small cell lung cancer after initial surgery. Fifty-five patients, receiving radiotherapy at Westmead Hospital between 1979 and 1997, were eligible for study. Data were collected retrospectively by reviewing patient records. The end-point was overall survival. Symptom control was also recorded. Prognostic factors for analysis included age, sex, original presenting stage, disease-free interval (DFI), performance status, site of recurrence, treatment intent and dose. The median overall survival was 11.5 months (95% confidence interval: 8.1-13.0). Survival following treatment with radical intent was 26 months compared to 10.5 months for patients treated with palliative intent (P = 0.025). There was no significant difference in survival for short (< or = 2 years) or long DFI, performance status, radiation dose, age, sex, site of recurrence or stage. Most patients (55%) had partial or complete resolution of symptoms. Radiotherapy results in overall post-recurrence median survival of nearly 1 year, consistent with previous published data. Radical treatment intent predicts better prognosis as a result of patient selection and higher dose. Radiotherapy is effective at palliating symptoms of this disease.     

Feasibility of integrating high-spatial-resolution 3D breath-hold coronary MR angiography with myocardial perfusion and viability examinations

The study was institutional review board approved and Health Insurance Portability and Accountability Act compliant. All subjects provided informed consent. Three-dimensional breath-hold coronary magnetic resonance (MR) angiography with use of steady-state free precession was performed in 12 patients up to 20 minutes after 0.2 mmol gadolinium-based contrast material per kilogram of body weight was administered. Within 24 heartbeats, a spatial resolution of up to 1.0 x 1.2 x 2.0 mm was achieved. Sixty-five (82%) of the 79 visualized coronary artery segments had a grade of 3 or 4 on a four-point scale of depiction in which grade 4 indicated excellent depiction. Twenty-seven percent (n = 21) of the 79 segments were assigned a grade of 4; 56% (n = 44), a grade of 3; 16% (n = 13), a grade of 2; and 1% (n = 1), a grade of 1. Coronary MR angiography performed as part of a first-pass myocardial perfusion and viability assessment MR imaging examination is feasible and does not involve additional imaging time.     

Suprapineal recess: an alternate site for third ventriculostomy? Case report

This 30-year-old woman presented with clinical symptoms and signs of intracranial hypertension and Parinaud syndrome secondary to ventriculoperitoneal shunt dysfunction. Magnetic resonance (MR) imaging revealed gross triventricular hydrocephalus with a large suprapineal recess due to aqueductal stenosis. Using an endoscopic approach, a ventriculostomy was performed within the floor of the dilated suprapineal recess. Following this procedure the patient experienced alleviation of all her neurological symptoms and signs. Postoperative MR imaging and cerebrospinal fluid flow studies demonstrated a functioning ventriculostomy. The anatomy of the suprapineal recess and its suitability for endoscopic ventriculostomy are discussed.     

Effect of overexpressed adenylyl cyclase VI on beta 1- and beta 2-adrenoceptor responses in adult rat ventricular myocytes

1. Adenylyl cyclase VI (ACVI) is one of the most abundantly expressed beta adrenergic receptor (betaAR)-coupled cyclases responsible for cyclic AMP (cAMP) production within the mammalian myocardium. We investigated the role of ACVI in the regulation of cardiomyocyte contractility and whether it is functionally coupled with beta(1) adrenergic receptor (beta(1)AR). 2. Recombinant adenoviruses were generated for ACVI and for antisense to ACVI (AS). Adult rat ventricular myocytes were transfected with ACVI virus, AS or both (SAS). Adenovirus for green fluorescent protein (GFP) served as control. Myocyte contraction amplitudes (% shortening) and relaxation times (R50) were analysed. ACVI function was determined using cAMP assays. 3. ACVI-transfected cells demonstrated a strong 139 kDa ACVI protein band compared to controls. ACVI myocytes had higher steady-state intracellular cAMP levels than GFP myocytes when unstimulated (GFP vs ACVI=6.60+/-0.98 vs 14.2+/-2.1 fmol cAMP/viable cell, n=4, P<0.05) and in the presence of 1 microm isoprenaline or 10 microm forskolin. 4. ACVI myocytes had increased basal contraction (% shortening: GFP vs ACVI: 1.90+/-1.36 vs 3.91+/-2.29, P<0.0001) and decreased basal R50 (GFP vs ACVI: 62.6+/-24.2 ms (n=50) vs 45.0+/-17.2 ms (n=248), P<0.0001). ACVI myocyte responses were increased for forskolin (E(max): GFP=6.70+/-1.59 (n=6); ACVI=9.06+/-0.69 (n=14), P<0.01) but not isoprenaline. 5. ACVI myocyte responses were increased (E(max): GFP vs ACVI=3.16+/-0.77 vs 5.10+/-0.60, P<0.0001) to xamoterol (a partial beta(1)AR-selective agonist) under beta(2)AR blockade (+50 nm ICI 118, 551). AS decreased both control and ACVI-stimulated xamoterol responses (E(max): AS=2.59+/-1.42, SAS=1.38+/-0.5). ACVI response was not mimicked by IBMX. Conversely, response through beta(2) adrenergic receptor (beta(2)AR) was decreased in ACVI myocytes. 6. In conclusion, ACVI overexpression constitutively increases myocyte contraction amplitudes by raising cAMP levels. Native ACVI did not contribute to basal cAMP production or contraction amplitude and only to a minor extent to the forskolin response. beta(1)AR but not beta(2)AR coupling was dependent on ACVI.     

A comparison of prospective and retrospective respiratory navigator gating in 3D MR coronary angiography

A comparison between the prospective and retrospective respiratory navigator gating in MR coronary angiography was performed with eight normal subjects. A three-dimensional (3D) ECG-gated fast gradient echo pulse sequence was used for image data acquisition. The results show that the MR coronary angiography obtained using retrospective gating retains a considerable amount of motion artifacts. In this study, the images acquired using prospective navigator gating demonstrated significantly reduced motion artifacts (p = 0.009), improved vessel visibility (p = 0.021) with reduced imaging time (p = 0.013) compared to the images obtained using retrospective navigator gating.     

Correlation of intravesical prostatic protrusion with bladder outlet obstruction

OBJECTIVES: To determine the effect of intravesical protrusion of the prostate (IPP, graded I to III) on lower urinary tract function, by correlating it with the results of a pressure-flow study. PATIENTS AND METHODS: In a prospective study men (aged> 50 years) with lower urinary tract symptoms were initially evaluated as recommended by the International Consultation on Benign Prostatic Hyperplasia, together with the IPP and prostate volume, as measured by transabdominal ultrasonography. These variables were then correlated with the results from a pressure-flow study. RESULTS: The IPP was a statistically significant predictor (P < 0.001) of bladder outlet obstruction (BOO) compared with other variables in the initial evaluation. In all, 125 patients had significant BOO, defined as a BOO index of> 40. Of these men, 94 had grade III and 30 had grade I-II IPP. Seventy-five patients had a BOO index of < 40; 69 had grade I-II and six grade III IPP. In patients with BOO confirmed on the pressure-flow study, grade III IPP was associated with a higher BOO index than was grade I-II (P < 0.001). CONCLUSION: The IPP assessed by transabdominal ultrasonography is a better and more reliable predictor of BOO than the other variables assessed.     

Coronary artery magnetic resonance imaging: a patient-tailored approach

Coronary artery magnetic resonance imaging strategies have tended to focus on the use of a single method performed during either breath-holding or free-breathing for all patients. However, significant variations exist among patients in terms of breath-holding ability and respiratory regularity that make the use of a single technique alone not universally successful. Therefore, it is prudent to make available a number of magnetic resonance imaging methods such that an appropriate respiratory motion reduction strategy can be tailored to suit the patient's respiratory pattern and characteristics. A tailored approach that can draw on different image acquisition techniques for coronary artery imaging is presented. A decision tree is proposed to triage patients into imaging regimes with the greatest probability of success, according to the patient's ability to breath-hold or exhibit steady respiration. Methods include volume free-breathing acquisitions using navigator echoes for respiratory monitoring in the 8- to 10-min scan time range, two-dimensional spiral navigators (2- to 3-min scan time), breath-held multislice and vessel-tracking spirals (16- to 20-second scan time), and real-time imaging approaches incorporating adaptive signal averaging. The development of multiple acquisition strategies substantially improves the opportunities to generate high-quality, diagnostic images of the coronary arteries.     

Does the use of mean or median Z-score of the thyroid volume indices provide a more precise description of the iodine deficiency disorder status of a population?

Endemic iodine deficiency is largely an environmental problem affecting whole populations. Currently, thyroid volume data from a population are analyzed with the sole objective of obtaining an estimate of goitre prevalence using +97th percentile or +2 standard deviations of an appropriate reference as cut-off. This paper proposes an alternative approach to the analysis and presentation of thyroid volume data using Z-scores (standard deviation scores) of the thyroid volume indices such as thyroid volume-for-age or thyroid volume-for-body surface area. The calculation of the summary statistics of the Z-scores, such as mean or median, provides an alternative to the prevalence-based approach for expressing severity of iodine deficiency disorders (IDD). An advantage of the mean or median Z-score is that it describes the thyroid volume profile (and therefore the IDD status) of the entire population directly, unlike goitre prevalence which gives information only about the extremes of distribution. The frequency curve or histogram of the Z-scores provides a complete picture of the whole distribution. Although qualitatively similar conclusions on IDD severity can be drawn from both analytical approaches, only the Z-score system is able to capture adequately the trends or changes in thyroid size over time, and to establish whether a previously iodine-deficient community's thyroid volume profile has returned to 'normal' (as indicated by a distribution that is not significantly different from that of the reference) following intervention. As a continuous variable, Z-scores are particularly useful for the analysis of data from populations where the sample size is relatively small, or where many individuals lie outside the extreme percentiles of the reference population. In view of its advantages in the context of activities based on single and multiple measurements, the Z-score system is to be preferred for the reporting and use of thyroid volume indices. A desirable consequence of this preference is that national goals will be oriented towards an improvement of the overall thyroid volume profile of the population, rather than just a reduction of the number of individuals at the extremes.