Laser-patterned paper-based flow-through filters and lateral flow immunoassays to enable the detection of C-reactive protein.

We report the use of a laser-based fabrication process in the creation of paper-based flow-through filters that when combined with a traditional lateral flow immunoassay provide an alternative pathway for the detection of a pre-determined analyte over a wide concentration range. The laser-patterned approach was used to create polymeric structures that alter the porosity of the paper to produce porous flow-through filters, with controllable levels of porosity. When located on the top of the front end of a lateral flow immunoassay the flow-through filters were shown to block particles (of known sizes of 200 nm, 500 nm, 1000 nm and 3000 nm) that exceed the effective pore size of the filter while allowing smaller particles to flow through onto a lateral flow immunoassay. The analyte detection is based on the use of a size-exclusive filter that retains a complex (∼3 µm in size) formed by the binding of the target analyte with two antibodies each of which is tagged with different-sized labels (40 nm Au-nanoparticles and 3 µm latex beads), and which is larger than the effective pore size of the filter. This method was tested for the detection of C-reactive protein in a broad concentration range from 10 ng/ml to 100,000 ng/ml with a limit-of-detection found at 13 ng/ml and unlike other reported methods used for analyte detection, with this technique we are able to counter the Hook effect which is a limiting factor in many lateral flow immunoassays.

Dynamic contrast-enhanced perfusion processing for neuroradiologists: model-dependent analysis may not be necessary for determining recurrent high-grade glioma versus treatment effect.

BACKGROUND AND PURPOSE: Dynamic contrast-enhanced perfusion MR imaging has proved useful in determining whether a contrast-enhancing lesion is secondary to recurrent glial tumor or is treatment-related. In this article, we explore the best method for dynamic contrast-enhanced data analysis. MATERIALS AND METHODS: We retrospectively reviewed 24 patients who met the following conditions: 1) had at least an initial treatment of a glioma, 2) underwent a half-dose contrast agent (0.05-mmol/kg) diagnostic-quality dynamic contrast-enhanced perfusion study for an enhancing lesion, and 3) had a diagnosis by pathology within 30 days of imaging. The dynamic contrast-enhanced data were processed by using model-dependent analysis (nordicICE) using a 2-compartment model and model-independent signal intensity with time. Multiple methods of determining the vascular input function and numerous perfusion parameters were tested in comparison with a pathologic diagnosis. RESULTS: The best accuracy (88%) with good correlation compared with pathology (P = .005) was obtained by using a novel, model-independent signal-intensity measurement derived from a brief integration beginning after the initial washout and by using the vascular input function from the superior sagittal sinus for normalization. Modeled parameters, such as mean endothelial transfer constant > 0.05 minutes(-1), correlated (P = .002) but did not reach a diagnostic accuracy equivalent to the model-independent parameter. CONCLUSIONS: A novel model-independent dynamic contrast-enhanced analysis method showed diagnostic equivalency to more complex model-dependent methods. Having a brief integration after the first pass of contrast may diminish the effects of partial volume macroscopic vessels and slow progressive enhancement characteristic of necrosis. The simple modeling is technique- and observer-dependent but is less time-consuming.

CT imaging correlates of genomic expression for oral cavity squamous cell carcinoma.

BACKGROUND AND PURPOSE: Imaging correlates of genetic expression have been found for prognostic and predictive biomarkers of some malignant diseases, including breast and brain tumors. This study tests the hypothesis that imaging findings correlate with relevant genomic biomarkers in oral cavity squamous cell carcinoma. MATERIALS AND METHODS: Surplus frozen tissue from 27 untreated patients with oral cavity squamous cell carcinoma who underwent preoperative CT imaging was analyzed for gene expression. A team of neuroradiologists blinded to the genomic analysis results reviewed an extensive list of CT findings. The imaging correlated with genomic expression for cyclin D1, angiogenesis-related genes (vascular endothelial growth factor receptors and ligands), which relate to enhancement on the basis of other tumor types; and epidermal growth factor receptor, which may relate to proliferation and mass effect. RESULTS: Expression of vascular endothelial growth factor receptors 1 and 2 correlated with the enhancement of the primary tumor (P = .018 and P = .025, respectively), whereas the epidermal growth factor receptor correlated with mass effect (P = .03). Other exploratory correlations included epidermal growth factor receptor to perineural invasion (P = .05), and certain vascular endothelial growth factor receptors and ligands to mass effect (P = .03) and increased (P = .01) or decreased (P = .02) primary tumor size. CONCLUSIONS: We report that CT imaging correlates with gene expression in untreated oral cavity squamous cell carcinoma. Enhancement of the primary tumor and degree of mass effect correlate with relevant genomic biomarkers, which are also potential drug targets. Eventually, treatment decisions may be aided by combining imaging findings into meaningful phenotypes that relate directly to genomic biomarkers.

Improving imaging diagnosis of persistent nodal metastases after definitive therapy for oropharyngeal carcinoma: specific signs for CT and best performance of combined criteria.

BACKGROUND AND PURPOSE: Criteria for detection of persistent nodal metastases in treated oropharyngeal tumors are sensitive but nonspecific, leading to unnecessary nodal dissections. Developing specific imaging criteria for persistent nodal metastases could improve diagnosis while decreasing patient morbidity. MATERIALS AND METHODS: Patients with oropharyngeal squamous cell carcinoma with nodal metastases treated by definitive radiation therapy and subsequent nodal dissection were retrospectively evaluated. One hundred thirty-eight patients had pre- and posttherapy contrast-enhanced CTs evaluated by radiologists blinded to the status of pathologically proved hemineck persistent nodal metastases. Composite scoring criteria for CT, combined from individual parameters, were compared with radiologists' opinions, previous multiparameter criteria, and outcome data. RESULTS: New low-attenuation areas and a lack of size change (<20% cross sectional area) were both highly specific for persistent nodal metastases (99%; P = .0004). Extranodal disease on pretherapy imaging was moderately specific (86%; P = .001). The CSC correctly placed 29 patients in a low-risk category compared with 14 by previously reported criteria and radiologist reports. With good second-rater reliability, the CSC cutoff values stratified patients at highest risk of persistent nodal metastases, thereby improving specificity while maintaining sensitivity. CONCLUSIONS: Comparing pre- and posttherapy examinations improves specificity by discriminating focal findings and size change compared with a single time point. The CSC can categorize the risk of persistent nodal metastases more accurately than previous CT methods. This finding has the potential to improve resource use and reduce surgical morbidity.

Preoperative grip strength measurement and duration of hospital stay in patients undergoing total hip and knee arthroplasty.

PURPOSE: This study explored whether a relationship exists between preoperative pinch and power grip strength, and length of hospital stay in patients undergoing hip and knee arthroplasty at a busy UK hospital. We investigated whether handgrip dynamometry could be used preoperatively to identify patients at greater risk of longer inpatient stays. This would allow focussed intervention preoperatively and facilitate predictors of length of stay postoperatively. METHODS: One hundred and sixty-four patients (64 male, 100 female) undergoing lower limb arthroplasty (83 total knee replacement, 81 total hip replacement) were assessed in pre-admission clinic. Average measurements of pinch grip, power grip and grip endurance were taken from each patient using the Jamar hydraulic dynamometer (Jamar, USA). Duration of inpatient stay of each patient was recorded. RESULTS: Average duration of hospital stay was 9.4 days. Both average pinch grip strength and average power grip strength had a significant negative correlation with duration of inpatient stay. Those patients with a pinch grip strength less than 6.3 kg remained an inpatient for an average of 2 days longer than those with a pinch grip greater than 6.3 kg. CONCLUSIONS: This simple test may be highly beneficial preoperatively in identifying those patients likely to require longer inpatient stays and therefore those who would benefit from early nutritional intervention and focussed physiotherapy. It may also facilitate predictors of length of stay postoperatively. We believe this may effect significant cost reductions in the NHS.

Fecundity and life table of different morphotypes of Phlebotomus argentipes (Diptera: Psychodidae).

Phlebotomus argentipes Annandale and Brunetti (Diptera: Psychodidae), the established vector for Visceral Leishmaniasis (VL) have shown some morphological variations in India and its subcontinents. The variable egg laying capacity was found in different morphotypes of P. argentipes with maximum in type III followed by type I and II. The fecundity was enhanced by providing 25% glucose soaked filter paper surface in all types. However, significant increase was found in type-I (P < 0.05). The differences in fecundity indicate the biological variations among P. argentipes population. The findings will be helpful in searching out the sibling species among P. argentipes population.

The use of remote sensing in the identification of the eco-environmental factors associated with the risk of human visceral leishmaniasis (kala-azar) on the Gangetic plain, in north-eastern India.

Human visceral leishmaniasis (VL) or kala-azar remains a major cause of mortality, particularly in the developing world. The disease is common in the internal regions of north-eastern India, which have a tropical or sub-tropical climate. In a recent study on VL in this region, the relationship between the incidence of VL and certain physio-environmental factors was explored, using a combination of a geographical information system (GIS), satellite imagery and data collected 'on the ground'. Some eco-environmental parameters were then used to map and describe the spatial heterogeneity seen in the transmission of the parasite (Leishmania donovani) that causes VL in India, and to identify those habitats, on the Gangetic plain, where the sandfly vectors might thrive. It was found that the presence of waterbodies, woodland and urban, built-up areas, soil of the fluvisol type, air temperatures of 25.0-27.5 degrees C, relative humidities of 66%-75%, and an annual rainfall of 100-<160 cm were all positively associated with the incidence of VL. A VL map was created and stratified into areas of 'risk' and 'non-risk' for the disease, based on calculations of risk indices.

Vector density and the control of kala-azar in Bihar, India.

Bihar, India has been in the grip of kala-azar for many years. Its rampant and severe spread has made life miserable in most parts of the state. Such conditions require a comprehensive understanding of this affliction. The numbers coming out of the districts prone to the disease in the north and south Ganges have provided us with several startling revelations, as there are striking uniformities on both sides, including similar vegetation, water storage facilities, house construction and little change in risk factors. The northern areas have been regularly sprayed with DDT since 1977, but eradication of the disease appears to be a distant dream. In 2007 alone, there were as many as 37,738 cases in that region. In contrast, the southern districts of Patna and Nalanda have never had the disease in its epidemic form and endemic disease has been present in only some pockets of the two districts. In those cases, two rounds of spraying with DDT had very positive results, with successful control and no new established foci. In addition, an eleven-year longitudinal study of the man hour density and house index for the vector Phlebotomus argentipes demonstrated that they were quite high in Patna and Nalanda and quite low in north Bihar. Given these facts, an attempt has been made to unravel the role of P. argentipes saliva (salivary gland) in the epidemiology of kala-azar. It was determined that patchy DDT spraying should be avoided for effective control of kala-azar.

A report on the indoor residual spraying (IRS) in the control of Phlebotomus argentipes, the vector of visceral leishmaniasis in Bihar (India): an initiative towards total elimination targeting 2015 (Series-1).

BACKGROUND & OBJECTIVES: Visceral leishmaniasis, commonly known as kala-azar is endemic in Bihar state, India. Current vector control programme in Bihar focuses mainly on spraying the sandfly infested dwellings with DDT. The Government of India in collaboration with WHO has fixed the target 2015 for total elimination of kala-azar. The present study was carried out to see the impact of DDT and improved IEC in the containment of vector density vis-à-vis disease transmission. METHODS: Before the start of the spraying operations training was imparted to all the medical and paramedical personnel regarding the methods of spraying operations. Pre- and post-sandfly density was monitored in four selected districts. Incidences of kala-azar cases were compared for pre- and post-spray periods. Social acceptability and perceptions of households was collected through questionnaires from 500 randomly selected households in the study districts. RESULTS: House index in three study districts reduced considerably during post-spray when compared to pre-spray. Kala-azar incidence in many districts was reduced after the DDT spray. Either partial or complete refusal was reported in 14.4%, while 35% were not satisfied with the suspension concentration and coverage; and 46.6% were found satisfied with the spraying procedure. INTERPRETATION & CONCLUSION: Strengthening the IEC activities to sensitise the community, proper training of health personnel, monitoring of spray, good surveillance, proper treatment of cases and two rounds of DDT spray with good coverage in the endemic districts up to three years are essential to achieve the desired total elimination of kala-azar in Bihar state.

The pattern of ankle fractures sustained by outdoor activities at the Snowdonia National Park, North Wales, United Kingdom.

OBJECTIVE: The aim of this study was to review the pattern of ankle fractures sustained by patients brought to the Emergency Department at Ysbyty Gwynedd from The Snowdonia National Park. MATERIALS AND METHODS: The study group included all patients with ankle fractures on the mountain medicine database between March 2004 and December 2006. The presence of talar shift and comminution of the medial malleolus was noted. The pattern of fractures were analysed and compared with the literature. Radiographs were obtained for 20 casualties. RESULTS: 70% of these were injured whilst hill walking. Open fractures represented 12% of injuries. 75% of fractures required operative fixation. Weber B injuries were the commonest followed by Weber C and A. Talar shift was seen in 80% of the cases and 45% showed comminution of the medial malleolus. CONCLUSIONS: In our case series we observed a high proportion of open and unstable ankle fractures, with the majority treated by operative fixation. The high rate of comminution of the medial malleolus has previously not been reported in the literature and has the potential of making operative fixation technically difficult. Encouraging the use of walking poles particularly at the time of descending may help to reduce the incidence of ankle fractures in hill walkers.

The importance of surgical education in the accuracy of implant placement during hip fracture fixation.

BACKGROUND: Studies have found that tip apex distance (TAD) is the strongest independent predictor of lag screw cut-out following hip fracture fixation. The objective of this study was to understand the importance of introducing the concept of TAD to surgeons. The null hypothesis was that there were no differences between fractures fixed before awareness of TAD compared with fractures fixed after awareness of TAD. MATERIALS AND METHODS: This study involved assessing 75 consecutive radiographs retrospectively (before introduction of "tip apex distance" to surgeons) and 83 consecutive radiographs prospectively (after introduction of "tip apex distance" to surgeons). Radiographs were measured using a radiograph digitizer and software. RESULTS: Average TAD in radiographs measured retrospectively was 22.6 mm compared with 9.7 mm in radiographs analysed prospectively (P

Survey of the initial management and imaging protocols for occult scaphoid fractures in UK hospitals.

OBJECTIVE: The aim of this research was to survey how occult fractures of the scaphoid bone are both imaged and managed initially. MATERIALS AND METHODS: A total of 832 questionnaires were sent via e-mail to active associate members of the British Orthopaedic Association. Included was a series of questions regarding the timing of initial and subsequent orthopaedic review of this group of patients and the use of serial radiographs and second-line imaging techniques. RESULTS: Nearly half of the UK's acute NHS trusts were represented (45%). The response rate was 16% (130 out of 832). Only 16% of respondents were aware of a local imaging protocol for the investigation of suspected fractures of the scaphoid. Ninety-four percent of respondents performed a second radiograph at first fracture clinic review. Fifty-eight percent used magnetic resonance imaging (MRI) as a second-line investigation; with computed tomography scan and radionuclide isotope bone scan being performed by 26% and 16% respondents, respectively. CONCLUSIONS: The survey revealed a wide variation in the management of occult fractures of the scaphoid. MRI has been shown to be both sensitive and specific in diagnosing occult carpal bone fractures. There is a need to standardise the management of these injuries to ensure early diagnosis and limit unnecessary wrist immobilisation.

Improving fat-suppressed T2-weighted imaging of the head and neck with 2 fast spin-echo dixon techniques: initial experiences.

Two modified fast spin-echo (FSE) techniques (a 2-point and a single-scan triple-echo Dixon) were used for T2-weighted imaging of the head and neck in 7 patients along with conventional FSE with fat saturation. Both Dixon techniques provided consistent and more uniform fat suppression (FS) than conventional FSE. The 2-point Dixon technique was noted to be more susceptible to motion artifacts. The triple-echo Dixon technique offered the best scan time efficiency and overall image quality.

The shrinking thyroid: how does thyroid size change following radiation therapy for laryngeal cancer?

BACKGROUND AND PURPOSE: External beam radiation therapy (XRT) for head and neck cancer is known to induce hypothyroidism and cause morphologic changes in the thyroid gland. This retrospective study investigates change in the size of the thyroid gland detectable by CT after XRT for laryngeal cancer. MATERIALS AND METHODS: The measured width of the thyroid lobes in 61 patients treated nonsurgically with XRT for laryngeal cancer between 2000 and 2003 on posttherapy CT was compared with that on pretherapy CT. Absolute and percentage changes in measured thyroid width following XRT were analyzed according to chemotherapy administration and posttherapy thyroid function. RESULTS: Eighty-five percent (52/61) of patients had a decrease in the width of the thyroid gland. The average change in width measuring -4.7 mm and -13.8% (SD, 5.7 mm and 19.9%) occurred at an average of 758 days following completion of XRT (mean, 402-1534 days) and was significant (P = .002). Average change in width between hypothyroid patients (n = 19, -6.1 mm and -20.0% change) and euthyroid patients (n = 42, -4.1 mm and -11.1% change) was not significant (P = .20 absolute change and P = .11 percentage change). The average change in width between patients receiving chemotherapy (n = 31, -5.5 mm and -16.1% change) and patients not receiving chemotherapy (n = 30, -3.9 mm and -11.5% change) was not significant (P = .26 absolute change and P = .37 for percentage change). CONCLUSIONS: Most nonsurgical patients receiving XRT for laryngeal cancer have a significant decrease in the width of their thyroid glands detected on CT. The average change in the size of the thyroid gland does not differ when development of hypothyroidism or chemotherapy administration are considered.

Emergence periodicity of Phlebotomus argentipes annandale and brunetti (Diptera: psychodidae): A laboratory study.

Phlebotomus argentipes Annandale and Brunetti (Diptera: Psychodidae) is the vector for visceral leishmaniasis in India. The aspects of its biology such as feeding and man vector contact are associated with emergence periodicity of the adult. Hence, the present study was made to find out the actual emergence period of P. argentipes. Wild caught P. argentipes were confined in the rearing pots inside laboratory. The newly emerged adults were collected at hourly intervals and released in to separate polythene bags and were held at 4°C till death. Sand flies were segregated sex-wise after the death under a microscope. The emergence of adult was observed throughout the day. However, the male preferred dawn emergence and the female the dusk. Two peaks of emergence were found in a day; first one in the morning (0900h) and the second one in the evening (1800h). The ratio of both sexes was found to be about equal. The emergence of adult was found to be 77% out of total eggs laid, which was completed within 7-10 days from the 1st day of emergence under laboratory conditions (25°C to 31°C and 70% to 75% relative humidity). This study has important bearings to find out the actual time for personal protection against biting of sand flies to prevent the transmission of Kala-azar.

Multidetector CT-Guided Lumbar Puncture in Patients with Cancer.

SUMMARY: Lumbar puncture can be performed for therapeutic purposes, to instill intrathecal chemotherapy for leptomeningeal cancer treatment or prophylaxis. This technique is generally performed blindly or under fluoroscopic guidance. However, in certain situations, lumbar puncture using multidetector CT (MDCT)-guided imaging may be beneficial, when other options have been exhausted or depending on the requirements of the performing radiologist's institution. The purpose of this article is to describe the technique and to evaluate outcomes of MDCT-guided lumber puncture for diagnostic and therapeutic purposes in patients with cancer. We conclude that MDCT-guided lumbar puncture is an effective and safe guiding modality for thecal sac access in patients with cancer, particularly where other methods of intrathecal access have failed.

Statin-induced muscular symptoms: a report of 3 cases.

Although the prescription of statin medication has increased worldwide and especially in Europe, its musculoskeletal side effects and their management strategy has not been highlighted in orthopaedic literature. We present three cases of statin-induced musculoskeletal symptoms which presented to an orthopaedic department. There were two patients with statin induced muscle pain (one in the thigh and one around the hip), and one with both myositis (with raised creatine kinase) and lupus-like symptoms. All of the symptoms resolved with stopping the statin. Muscle pain (often with normal creatine kinase) is the commonest side effect of statins. It is usually bilateral, but two of our cases presented with unilateral symptoms which made it more difficult to exclude a primary orthopaedic pathology. The widespread use of statins is likely to lead to an increase in the number of patients presenting to orthopaedic surgeons with muscle pain. It is important to consider muscle pain induced by statins in the differential diagnosis of acute or chronic pain in the limbs.

Parotid gland oncocytosis: CT findings with histopathologic correlation.

Oncocytic neoplasms result from metabolically altered cells that accumulate abundant mitochondria within their cytoplasm by oncocytic metaplasia. In this report, the CT findings are described and correlated with the histopathologic features of a case of oncocytoma involving the parotid gland that arose in a background of nodular oncocytic hyperplasia. When imaging demonstrates multiple small nodules in the parotid gland with a large, solid, or cystic mass, the diagnosis of oncocytic neoplasia should be considered.

A study of grip endurance and strengh in different elbow positions.

BACKGROUND: The aim of our study was twofold. The first was to investigate the optimum position of the elbow while measuring grip endurance. The second was to investigate the optimum position of the elbow while measuring peak grip strength. The American Society of Hand Therapists advocate estimation of grip strength with the elbow flexed at 90 degrees with the subject in the sitting position . As far as we are aware, there have been no reports in English literature regarding studies done to evaluate the position of the elbow while measuring grip endurance. MATERIALS AND METHODS: A total of 45 healthy adults (16 males, 29 females) participated in this study. A computerised handgrip analyser was used to measure the peak strength in the non-dominant hand, followed by measurement of the grip endurance. These measurements were conducted in 90 degrees of flexion and full extension of the elbow for each participant. RESULTS: Mean endurance in flexion was 71.0 N (SD 22.9) and in extension was 68.7 N (SD 27.4). Mean peak grip strength in flexion was 262.8 N (SD 73.1) and in extension was 264.1 N (SD 82.0). T test analysis showed no statistical significance for elbow positions for grip endurance (P = 0.67) and peak gip strength (P = 0.93). CONCLUSION: Practical implications from this study are that grip endurance training can be undertaken with the elbow in 90 degrees of flexion or full extension.