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1.
JPRAS Open ; 28: 10-18, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33614881

ABSTRACT

Though the thenar flap has been described since 1926, its use has not been widespread. The main criticisms are donor site morbidity and proximal interphalangeal joint (PIPJ) stiffness. In this paper, we describe a standard design technique for flap design and division to address these two issues. From July 2018 to April 2019, a total of ten patients underwent thenar flap reconstruction of the fingertip. The flap dimensions ranged from 10 mm × 10 mm to 25 mm × 15 mm. All the flaps survived. One patient developed wound infection post division. All donor sites were closed primarily without skin graft. We are using mirror image technique to elevate the flap to ensure that it is inset in the position as we planned without displacement. It largely reduced the chance of rotation and extensive tension when fix the finger to the thenar region. Our technique allows for the flap design to be individually customized based on the orientation of the defect, making it simpler and more replicable. We have also emphasized how care during division of the thenar flap can help prevent complications.

2.
Data Brief ; 30: 105609, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32395581

ABSTRACT

This article provides comprehensive experimental data of two water-swelling materials, water swelling rubber (WSR) and water-swelling polyurethane (WSP). Swelling tests, Dynamic Mechanical Analyzer (DMA) and Scanning Electron Microscope (SEM) were performed. Sealing properties of WSR and WSP were characterized by the data of swelling ratios (Sw and Sa), storage moduli (E') and images of micro-damage morphologies. These data can be useful for the prediction of the long-term waterproof performance of water-swelling materials and provide reference for material selection. The data presented herein was used for the article, titled "Laboratory evaluation of long-term sealing behaviors of two water-swelling materials for shield tunnel gasket" [1].

3.
Malays J Pathol ; 41(3): 243-251, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31901908

ABSTRACT

INTRODUCTION: Polymorphic expression of a CAG repeat sequence in the androgen receptor (AR) gene may influence the activity of the AR and the occurrence of prostate cancer and the TMPRSS2-ERG fusion event. Furthermore, this polymorphism may be responsible for the ethnic variation observed in prostate cancer occurrence and expression of the ERG oncogene. We investigate the expression of AR and ERG in the biopsies of Malaysian men with prostate cancer and in the same patients relate this to the length of the CAG repeat sequence in their AR gene. MATERIALS AND METHODS: From a PSA screening initiative, 161 men were shown to have elevated PSA levels in their blood and underwent prostatic tissue biopsy. DNA was extracted from the blood, and exon 1 of the AR gene amplified by PCR and sequenced. The number of CAG repeat sequences were counted and compared to the immunohistochemical expression of ERG and AR in the matched tumour biopsies. RESULTS: Of men with elevated PSA, 89 were diagnosed with prostate cancer, and 72 with benign prostatic hyperplasia (BPH). There was no significant difference in the length of the CAG repeat in men with prostate cancer and BPH. The CAG repeat length was not associated with; age, PSA or tumour grade, though a longer CAG repeat was associated with tumour stage. ERG and AR were expressed in 36% and 86% of the cancers, respectively. There was no significant association between CAG repeat length and ERG or AR expression. However, there was a significant inverse relationship between ERG and AR expression. In addition, a significantly great proportion of Indian men had ERG positive tumours, compared to men of Malay or Chinese descent. CONCLUSIONS: CAG repeat length is not associated with prostate cancer or expression of ERG or AR. However, ERG appears to be more common in the prostate cancers of Malaysian Indian men than in the prostate cancers of other Malaysian ethnicities and its expression in this study was inversely related to AR expression.


Subject(s)
Prostatic Neoplasms/genetics , Receptors, Androgen/genetics , Aged , Aged, 80 and over , Androgens/metabolism , Gene Expression/genetics , Humans , Male , Middle Aged , Prostatic Hyperplasia/genetics , Transcriptional Regulator ERG/genetics , Trinucleotide Repeats/genetics
4.
Public Health ; 176: 106-113, 2019 Nov.
Article in English | MEDLINE | ID: mdl-30509859

ABSTRACT

OBJECTIVES: This study was undertaken to investigate the occurrence of metabolic syndrome (MetS) and cardiovascular disease (CVD) risk in Orang Asli (OA), the indigenous people of Peninsular Malaysia. OA consist of Negrito, Proto-Malay, and Senoi groups who collectively comprise only 0.76% of the population of Peninsular Malaysia. Owing to the challenges in accessing their remote villages, these groups are often excluded in larger government health surveys. Although tropical diseases were scourges in the past, with rapid national development, many OA communities have been gradually urbanized. We believe an epidemiological transition is occurring and non-communicable diseases are on the rise. STUDY DESIGN: A retrospective cross-sectional study. METHODS: Indigenous Malaysians (n = 629) from three major groups (Negrito, Proto-Malay, and Senoi) were recruited, after ethics approval and informed consent. Body mass index (BMI), body weight, height, waist circumference, and systolic and diastolic blood pressure were measured, and participants were examined for acanthosis nigricans. Venous blood samples were used for measurements of fasting blood sugar, triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C). Insulin resistance was estimated using a surrogate measurement TG/HDL-C. The ratios of TC to HDL-C, and of LDL-C to HDL-C were determined. MetS was accessed according to the Joint Interim Statement of the IDF Tsak Force on Epidemiology and Prevention. RESULTS: MetS affected 29.57% of the OA population investigated and was significantly more prevalent (P < 0.05) in women than in men (35.25% vs 21.95%, P < 0.001). MetS prevalence was the highest among the Proto-Malays (39.56%), followed by Negritos (26.35%) and Senois (11.26%). The most prevalent risk factor among the Negritos with MetS was low HDL-C (95.35%), whereas central obesity was the most common risk factor among the Proto-Malays (82.91%). In contrast, hypertension was the commonest risk factor among the Senois with MetS (94.44%). Elevated TG/HDL-C ratios resulted in the highest risk for MetS among the OA population (relative risk [RR] = 7.01, 95% confidence interval [CI] = 3.58-13.72). The risk was almost four-fold among those with high TG (RR = 3.89, 95% CI = 3.08-4.91) and three-fold among those with BMI obesity (RR = 3.37, 95% CI = 2.61-4.36) and central obesity (RR = 2.99, 95% CI = 2.48-3.61). CONCLUSIONS: This may well be the first comprehensive report about MetS in OA indigenous communities in Malaysia. We have shown that rapidly urbanized OA communities had significant prevalence of MetS and associated cardiometabolic risk factors. Major contributory factors may include changes from previous hunter-gatherer lifestyles and subsistence diets to more urbanized lifestyles and easier access to high calorie foods.


Subject(s)
Cardiovascular Diseases/ethnology , Metabolic Syndrome/ethnology , Population Groups/statistics & numerical data , Adult , Cross-Sectional Studies , Female , Humans , Malaysia/epidemiology , Male , Prevalence , Retrospective Studies , Risk Factors
5.
Malays J Pathol ; 40(2): 103-110, 2018 Aug.
Article in English | MEDLINE | ID: mdl-30173226

ABSTRACT

INTRODUCTION: Prostate cancer is a heterogenous disease and the mechanisms that drive it to behave differently are not well understood. Tumour expression of the ERG oncogene occurs in the majority of patients with prostate cancer in Western studies. This is considered to be oncogenic as ERG acts as a transcription factor to regulate genes involved in tumour proliferation and invasion. In this study we investigated expression of ERG in Malaysian men with prostate cancer. METHODS: Tissues were collected from 80 patients with clinically detected prostate cancer and treated with radical prostatectomy. Cases were tested for ERG by immunohistochemistry using the mouse monoclonal antibody EP111. All blocks on 48 cases were tested in order to determine the extent of heterogeneity of ERG expression within individual cases. ERG expression was analysed in relation to patient age, ethnicity and tumour stage and grade. RESULTS: Forty-six percent of cases were ERG positive. There was no significant association between ERG and tumour grade or stage. Sixty-nine percent of Indian patients had ERG positive tumours; this was significantly higher (p=0.031) than for Chinese (40%) and Malay (44%) patients. Heterogeneity of ERG expression, in which both positive and negative clones were present, was seen in 35% of evaluated cases. Evaluation by tumour foci showed younger patients had more ERG positive tumour foci than older patients (p=0.01). Indian patients were more likely to have the majority of tumour foci with ERG staining positively, compared to either Chinese or Malay patients (P <0.01). CONCLUSION: In this study, tumour expression of ERG was more likely to occur in patients of Indian ethnicity.


Subject(s)
Adenocarcinoma/pathology , Biomarkers, Tumor/analysis , Prostatic Neoplasms/pathology , Aged , Humans , Malaysia , Male , Middle Aged , Transcriptional Regulator ERG/analysis , Transcriptional Regulator ERG/biosynthesis
6.
Cancer Radiother ; 22(3): 287-295, 2018 May.
Article in English | MEDLINE | ID: mdl-29699832

ABSTRACT

Modern standards of precision radiotherapy, primarily driven by the technological advances of intensity modulation and image guidance, have led to increased versatility in radiotherapy planning and delivery. The ability to shape doses around critical normal organs, while simultaneously "painting" boost doses to the tumor have translated to substantial therapeutic gains in head and neck cancer patients. Recently, dose adaptation (or adaptive radiotherapy) has been proposed as a novel concept to enhance the therapeutic ratio of head and neck radiotherapy, facilitated in part by the onset of molecular and functional imaging. These contemporary imaging techniques have enabled visualisation of the spatial molecular architecture of the tumor. Daily cone-beam imaging, besides improving treatment accuracy, offers another unique angle to explore radiomics - a novel high throughput feature extraction and selection workflow, for adapting radiotherapy based on real-time tumor changes. Here, we review the existing evidence of molecular and functional imaging in head and neck cancers, as well as the current application of adaptive radiotherapy in the treatment of this tumor type. We propose that adaptive radiotherapy can be further exploited through a systematic application of molecular and functional imaging, including radiomics, at the different phases of planning and treatment.


Subject(s)
Head and Neck Neoplasms/radiotherapy , Radiotherapy, Intensity-Modulated , Head and Neck Neoplasms/diagnostic imaging , Humans , Treatment Outcome
7.
J Forensic Leg Med ; 48: 15-21, 2017 May.
Article in English | MEDLINE | ID: mdl-28407514

ABSTRACT

Forensic odontology plays a vital role in the identification and age estimation of unknown deceased individuals. The purpose of this study is to estimate the chronological age from Cone-Beam Computed Tomography (CBCT) images by measuring the buccal alveolar bone level (ABL) to the cemento-enamel junction and to investigate the possibility of employing the age-related structural changes of teeth as studied by Gustafson. In addition, this study will determine the forensic reliability of employing CBCT images as a technique for dental age estimation. A total of 284 CBCT images of Malays and Chinese patients (150 females and 134 males), aged from 20 years and above were selected, measured and stages of age-related changes were recorded using the i-CAT Vision software. Lower first premolars of both left and right side of the jaw were chosen and the characteristics described by Gustafson, namely attrition, secondary dentine formation and periodontal recession were evaluated. Linear regression analysis was performed for the buccal bone level and the R values obtained were 0.85 and 0.82 for left and right side respectively. Gustafson's characteristics were analysed using multiple regression analysis with chronological age as the dependent variable. The results of the analysis showed R values ranged from 0.44 to 0.62. Therefore it can be safely concluded that the buccal bone level highly correlated with the chronological age and is consequently the most suitable age-related characteristic for forensic age estimation.


Subject(s)
Age Determination by Teeth/methods , Alveolar Process/diagnostic imaging , Dental Cementum/diagnostic imaging , Dental Enamel/diagnostic imaging , Adult , Alveolar Process/growth & development , Bicuspid/diagnostic imaging , Cementogenesis , Cone-Beam Computed Tomography , Cross-Sectional Studies , Dental Enamel/growth & development , Dentin, Secondary/diagnostic imaging , Female , Gingival Recession/diagnostic imaging , Humans , Linear Models , Malaysia , Male , Middle Aged , Retrospective Studies , Young Adult
8.
J Hand Surg Eur Vol ; 42(7): 700-705, 2017 Sep.
Article in English | MEDLINE | ID: mdl-27913804

ABSTRACT

In upper (C5-C7) and total (C5-T1) root avulsion brachial plexus injury, a method of double neurotization from a single donor spinal accessory nerve to two target nerves (suprascapular nerve and axillary nerve) may be done, leaving donor nerves available for reconstruction procedures to restore other aspects of upper limb function. A mean range of shoulder abduction of 91° (SD 25°) was achieved through this procedure in our study of 13 cases, of which seven cases were C5-C7 root avulsion and six cases were C5-T1 root avulsion brachial plexus injuries. Six of the former group and three of the latter group achieved >90° shoulder abduction. The technique of double neurotization from a single donor nerve provides favourable results in restoring shoulder abduction in avulsion brachial plexus injuries. LEVEL OF EVIDENCE: IV.


Subject(s)
Accessory Nerve/transplantation , Brachial Plexus Neuropathies/surgery , Brachial Plexus/injuries , Gracilis Muscle/transplantation , Peripheral Nerve Injuries/surgery , Adult , Brachial Plexus/surgery , Humans , Male , Middle Aged , Nerve Transfer/methods , Range of Motion, Articular , Shoulder Joint/physiology , Statistics, Nonparametric , Young Adult
9.
Malays J Pathol ; 38(2): 75-82, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27568663

ABSTRACT

Heat shock proteins (HSPs) are a family of evolutionary conserved proteins that work as molecular chaperones for cellular proteins essential for cell viability and growth as well as having numerous cyto-protective roles. They are sub-categorised based on their molecular weights; amongst which some of the most extensively studied are the HSP90 and HSP70 families. Important members of these two families; Heat shock proteins 70 and heat shock proteins 90 (Hsp70/90), are the glucose regulated proteins (GRP). These stress-inducible chaperones possess distinct roles from that of the other HSPs, residing mostly in the endoplasmic reticulum and mitochondria, but they can also be translocated to other cellular locations. Their ability in adapting to stress conditions in the tumour microenvironment suggests novel functions in cancer. GRPs have been implicated in many crucial steps of carcinogenesis to include stabilization of oncogenic proteins, induction of tumour angiogenesis, inhibition of apoptosis and replicative senescence, and promotion of invasion and metastasis.


Subject(s)
Carcinogenesis/metabolism , HSP70 Heat-Shock Proteins/metabolism , Heat-Shock Proteins/metabolism , Membrane Proteins/metabolism , Neoplasms/metabolism , Animals , Humans
10.
Anaesthesia ; 70(4): 393-9, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25311146

ABSTRACT

Emergence delirium is a significant problem in children regaining consciousness following general anaesthesia. We compared the emergence characteristics of 120 patients randomly assigned to receive a single intravenous dose of dexmedetomidine 0.3 µg.kg(-1) , propofol 1 mg.kg(-1) , or 10 ml saline 0.9% before emerging from general anaesthesia following a magnetic resonance imaging scan. Emergence delirium was diagnosed as a score of 10 or more on the Paediatric Anaesthesia Emergence Delirium scale. The incidence of emergence delirium was 42.5% in the dexmedetomidine group, 33.3% in the propofol group and 41.5% in the saline group (p = 0.671). Three patients in the dexmedetomidine group, none in the propofol group and two in the saline group required pharmacological intervention for emergence delirium (p = 0.202). Administration of neither dexmedetomidine nor propofol significantly reduced the incidence, or severity, of emergence delirium. The only significant predictor for emergence delirium was the time taken to awaken from general anaesthesia, with every minute increase in wake-up time reducing the odds of emergence delirium by 7%.


Subject(s)
Anesthesia, General/adverse effects , Delirium/prevention & control , Dexmedetomidine/therapeutic use , Magnetic Resonance Imaging/methods , Propofol/therapeutic use , Anesthesia Recovery Period , Child , Child, Preschool , Delirium/chemically induced , Dexmedetomidine/administration & dosage , Drug Administration Schedule , Female , Humans , Hypnotics and Sedatives/administration & dosage , Hypnotics and Sedatives/therapeutic use , Injections, Intravenous , Male , Propofol/administration & dosage , Time Factors
12.
J Anal Methods Chem ; 2012: 406162, 2012.
Article in English | MEDLINE | ID: mdl-22779036

ABSTRACT

A simple electrochemical deposition was developed to synthesize the cuprous oxide (Cu(2)O) octahedra on aluminum foils. The average edge length of the octahedra is about 300 nm. The chemical composition of the octahedra was determined using energy dispersive X-ray spectroscopy and electron energy-loss spectroscopy. The microstructure of the octahedra was investigated using transmission electron microscopy. The formation mechanism of the octahedra is proposed.

13.
AJNR Am J Neuroradiol ; 30(2): 373-7, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18854441

ABSTRACT

BACKGROUND AND PURPOSE: To our knowledge, there has been no study that compares the radiation dose delivered to the eye lens by 16- and 64-section multidetector CT (MDCT) for standard clinical neuroimaging protocols. Our aim was to assess radiation-dose differences between 16- and 64-section MDCT from the same manufacturer, by using near-identical neuroimaging protocols. MATERIALS AND METHODS: Three cadaveric heads were scanned on 16- and 64-section MDCT by using standard neuroimaging CT protocols. Eye lens dose was measured by using thermoluminescent dosimeters (TLD), and each scanning was repeated to reduce random error. The dose-length product, volume CT dose index (CTDI(vol)), and TLD readings for each imaging protocol were averaged and compared between scanners and protocols, by using the paired Student t test. Statistical significance was defined at P < .05. RESULTS: The radiation dose delivered and eye lens doses were lower by 28.1%-45.7% (P < .000) on the 64-section MDCT for near-identical imaging protocols. On the 16-section MDCT, lens dose reduction was greatest (81.1%) on a tilted axial mode, compared with a nontilted helical mode for CT brain scans. Among the protocols studied, CT of the temporal bone delivered the greatest radiation dose to the eye lens. CONCLUSIONS: Eye lens radiation doses delivered by the 64-section MDCT are significantly lower, partly due to improvements in automatic tube current modulation technology. However, where applicable, protection of the eyes from the radiation beam by either repositioning the head or tilting the gantry remains the best way to reduce eye lens dose.


Subject(s)
Lens, Crystalline/diagnostic imaging , Radiation Dosage , Radiation Injuries/prevention & control , Tomography, X-Ray Computed/methods , Cadaver , Calibration , Humans , Thermoluminescent Dosimetry
14.
Br J Ophthalmol ; 92(4): 509-12, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18310310

ABSTRACT

BACKGROUND/AIMS: Age-related macular degeneration (AMD) and vascular disease share similar risk factors. Recent data suggest AMD may independently predict stroke or coronary heart disease. We prospectively assessed the relationship between AMD and risk of stroke- or cardiovascular-related death in an Australian population. METHODS: Of 3654 baseline participants (1992-4) aged 49+ years, 2335 were re-examined after 5 years and 1952 after 10 years. Retinal photographs were graded using the Wisconsin System. History and physical examination provided data on possible risk factors. Deaths and cause of death were confirmed by data linkage with the Australian National Death Index. Risk ratios (RR) were estimated in Cox models. RESULTS: Among persons aged <75 years at baseline, early AMD predicted a doubling of cardiovascular mortality (RR, 2.32; 95% confidence interval (CI), 1.03 to 5.19), over the next decade, after controlling for traditional cardiovascular risk factors. Late AMD predicted fivefold higher cardiovascular mortality (RR, 5.57; 95% CI, 1.35 to 22.99) and 10-fold higher stroke mortality (RR, 10.21; 95% CI, 2.39 to 43.60) after adjusting for age and sex only. These associations were not present when persons older than 75 were included. CONCLUSION: AMD predicted stroke and cardiovascular events over the long term in persons aged 49-75 years. This may have potential implications for new intravitreal anti-VEGF AMD therapies.


Subject(s)
Cardiovascular Diseases/mortality , Macular Degeneration/mortality , Age Factors , Aged , Australia/epidemiology , Cardiovascular Diseases/complications , Epidemiologic Methods , Female , Humans , Macular Degeneration/complications , Male , Middle Aged , Prognosis , Stroke/complications , Stroke/mortality
15.
Singapore Med J ; 48(2): e53-6, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17304380

ABSTRACT

Although very rare, cases of cauda equina tumours migrating several levels have been known to occur. We report two cases of cauda equina schwannomas which migrated from its primary site, one caudally and the other one rostrally as confirmed by magnetic resonance imaging perioperatively. The first patient was a 27-year-old man and the second a 41-year-old man; both presented with back pain. This report aims to remind clinicians that certain tumours attached to the roots in the lumbar spinal canal may migrate.


Subject(s)
Back Pain/surgery , Cauda Equina/surgery , Neurilemmoma/surgery , Peripheral Nervous System Neoplasms/surgery , Adult , Back Pain/etiology , Humans , Male
16.
Singapore Med J ; 46(2): 74-7, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15678288

ABSTRACT

INTRODUCTION: Although spinal tumours are amenable to total surgical excision, the factors determining the outcome are diverse. This study re-evaluates aspects of the disease that contribute to their outcome. METHODS: Ninety-three consecutive patients with spinal cord tumours that underwent microsurgical excision between February 1992 and February 2002 were retrospectively studied. All patients underwent magnetic resonance imaging and had histological confirmation of spinal tumours. RESULTS: There were 44 men and 49 women with a mean age of 49.05 years (range 6 to 83 years). The location of the tumours was cervical in 37 cases, thoracic in 41 cases, lumbosacral in 13 cases, and multilevel in two cases. The mean tumour size was 2.2 cm (range 0.8 to 7 cm) and mean duration of symptoms was 10.8 months. Complete excision was achieved in 72 cases and incomplete removal in 15 cases. The mean follow-up period was 21.45 months (range 3 days to 8 years). Immediate post-operative improvement was noted in 40 (43 percent) patients, 24 (25.4 percent) improved within six months, 13 (14 percent) improved after six months, 12 (12.9 percent) had no improvement and four patients died. The duration of symptoms and the completeness of excision were factors that correlated with post-operative improvement (p-value is less than 0.05). Age, gender, size, histological type, presenting symptoms, spinal level affected and axial location of tumour did not correlate with the outcome. CONCLUSION: Microsurgical excision of spinal cord tumours is a safe and effective procedure, and post-operative outcome is correlated to duration of symptoms and the extent of tumour resection.


Subject(s)
Microsurgery , Spinal Cord Neoplasms/surgery , Spine/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Child , Female , Humans , Male , Middle Aged , Postoperative Complications , Retrospective Studies , Time Factors , Treatment Outcome
17.
Exp Clin Endocrinol Diabetes ; 111(1): 44-6, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12605350

ABSTRACT

The circadian rhythm of melatonin secretion was measured in 20 healthy males (20 - 32 yrs.) after intake of placebo or various doses of a special extract of Agnus castus (AC: 120 - 480 mg/die) for 14 days. A significant (p < 0.05) dose-dependent increase of the area under the melatonin secretion curve (AUC) was found. The pattern of circadian rhythm of melatonin secretion was, however, not influenced. It remains to be elucidated whether the AC-stimulated increase of melatonin secretion is suitable for treatment of sleep disturbances.


Subject(s)
Melatonin/metabolism , Plants, Medicinal/chemistry , Adult , Area Under Curve , Circadian Rhythm/physiology , Dose-Response Relationship, Drug , Humans , Male , Plant Extracts/pharmacology
18.
J Acoust Soc Am ; 109(6): 3055-64, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11425148

ABSTRACT

The effect of array geometry on the steering performance of ultrasound phased arrays is examined theoretically, in order to maximize array performance under the given anatomical constraints. This paper evaluates the performance of arrays with spherical and cylindrical geometry, determined by using computer simulations of the pressure fields produced at various extremes of steering. The spherical segment arrays were truncated for insertion into the rectum, and contained either annular or linear elements. The cylindrical arrays were either flat or had a variable curvature applied along their length. Fields were computed by dividing the array elements into many point sources. The effectiveness of an array configuration when steered to a particular focal location was assessed by defining a parameter, G, as the ratio of the intensity at the desired focus to the maximum intensity of any unwanted lobes. The performance of truncated spherical arrays with annular elements was evaluated for focal steering along the array axis (in depth, in the z direction). When steered 15 mm toward the source, these truncated spherical annular arrays exhibited excellent performance, with G>5.7 for arrays containing more than 10 elements. Similarly, the spherical arrays with linear elements performed well when steered along the array axis to the same degree, with G>7 (for element widths up to 3 lambda), though many more array elements were required. However, when these arrays were steered 15 mm laterally, along the length of the prostate (the y direction), the value for G fell below 1 for element widths greater than about 1.6 lambda. It was found that the cylindrical arrays performed much better for y-direction steering (G>4, for 60 mm arrays with an element width of 1.75 lambda), but their performance was poorer when steered in the z direction (G approximately 4 for an element width of 1.5 lambda). In order to find a compromise between these extremes, a curved cylindrical array was examined, which was a cylindrical array with additional curvature along its length. These curved cylindrical arrays yielded performance between that of spherical linear arrays and cylindrical arrays, with better steering along the y direction than the spherical arrays and better z-direction steering than the cylindrical arrays.


Subject(s)
Models, Biological , Prostatic Diseases/therapy , Prostatic Neoplasms/therapy , Ultrasonic Therapy/methods , Humans , Male
19.
Clin Infect Dis ; 32(11): 1562-6, 2001 Jun 01.
Article in English | MEDLINE | ID: mdl-11340527

ABSTRACT

We describe a patient with community-acquired pneumonia due to Legionella pneumophila serogroup 6. This patient was found to have bronchoalveolar carcinoma of the lung by means of cytologic testing in 1 of 2 bronchoalveolar lavage samples, but no lesions were visible on bronchoscopy. Despite intravenous administration of azithromycin to the patient, repeat culture and polymerase chain reaction showed persistence of Legionella; the isolates remained susceptible to azithromycin. The patient did not respond to 14 doses of daily intravenously administered azithromycin. The poor outcome may have been partially due to the suspected underlying lung malignancy, as shown by cytologic examination, and by a delay in seeking medical attention.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Azithromycin/therapeutic use , Community-Acquired Infections/drug therapy , Legionnaires' Disease/drug therapy , Pneumonia, Bacterial/drug therapy , Aged , Community-Acquired Infections/diagnostic imaging , Community-Acquired Infections/microbiology , Community-Acquired Infections/physiopathology , Fatal Outcome , Female , Humans , Legionella pneumophila/drug effects , Legionella pneumophila/genetics , Legionella pneumophila/isolation & purification , Legionnaires' Disease/diagnostic imaging , Legionnaires' Disease/microbiology , Legionnaires' Disease/physiopathology , Microbial Sensitivity Tests , Pneumonia, Bacterial/diagnostic imaging , Pneumonia, Bacterial/microbiology , Pneumonia, Bacterial/physiopathology , Radiography , Treatment Failure
20.
J Clin Densitom ; 4(1): 31-6, 2001.
Article in English | MEDLINE | ID: mdl-11309517

ABSTRACT

The placement of most spinal interbody devices is above the cancellous region of the vertebral bodies. Dual X-ray absorptiometry (DXA) scans of patients are usually taken from the anterior-posterior or the lateral projection. DXA scans taken in vitro from the axial direction would most closely indicate the bone mineral density (BMD) of the bone at this region. So far, in vitro studies have not been conducted to determine the correlation between axial and lateral scans. Because lateral DXA BMD scans are noninvasive and have low radiation dosage, they could be used as a predictive tool to determine the quality of cancellous bone at the centrum of the vertebral bodies, where spinal interbody devices are commonly placed.


Subject(s)
Absorptiometry, Photon/methods , Bone Density , Lumbar Vertebrae/physiology , Adult , Aged , Humans , Middle Aged , Predictive Value of Tests , Spinal Fusion
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