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Diagnosis of internal carotid artery occlusion by dynamic computed tomography.

To evaluate internal carotid artery occlusion noninvasively by means of computed tomography (CT), dynamic CT studies with intravenous bolus injection of contrast medium were performed in 13 patients with hemispheric cerebral infarction and one patient with vascular headache. The slice level of dynamic CT was fixed at the atlas. The initial CT scan was taken after the start of infection of 20 or 40 ml of 60% meglumine amidotrizoate (this scan was used as a precontrast density reference), and 10 additional scans were made during 51.6 sec from the start of injection. The occluded internal carotid arteries were not visualized in patients with ICA occlusion, while all nonoccluded internal carotid arteries proven by angiography were enhanced clearly. It is concluded that this simple and noninvasive diagnostic examination should be added to the routine test procedures for evaluation and follow-up study of extracranial cerebral vascular disease.

Arterial Occlusive Diseases↗

Radiographic stage of osteoarthritis or sex of the patient does not predict one year outcome after total hip arthroplasty.

OBJECTIVE: To investigate whether patients with severe radiographic osteoarthritis (OA) have a different outcome at one year after total hip replacement than patients with moderate radiographic OA. To investigate sex related differences in preoperative radiographic and self reported status and in postoperative outcome. METHODS: 184 patients (96 women) with a mean age at surgery of 71.4 years (50-92), with primary OA of the hip were investigated preoperatively and six and 12 months postoperatively with two self administered questionnaires, SF-36 and WOMAC. The radiographs were evaluated by two independent radiologists using an atlas. Minimal joint space narrowing, osteophytes, cysts, sclerosis, and deformity were assessed. A summary grade 0-3 was made, based on joint space, where 3 is severe OA. The reference population for SF-36 consisted of 2901 subjects matched for age and sex from the general Swedish population. RESULTS: 162 patients fulfilled the study criteria. 113 had grade 3, 47 grade 2, and two grade 1 radiographic OA. There was no difference in preoperative or postoperative pain and physical impairment between patients with moderate and severe radiographic OA. There were no sex related differences in preoperative radiographic status, or in postoperative outcome. Neither were any differences in preoperative radiographic status of OA found in patients with previous total hip replacement of the contralateral hip, compared with those who had not been operated on before. All patients, regardless of preoperative radiographic OA stage, showed significant postoperative improvement and at one year achieved a health related quality of life similar to that of the reference group. CONCLUSION: The severity of radiographic changes indicating OA often weighs heavily in the surgeon's decision to perform a total hip replacement. Yet, the findings of this study emphasise that the preoperative radiographic stage of OA has no correlation with the postoperative outcome after one year. Furthermore, this study failed to detect any sex related differences in preoperative radiographic and self reported status or in postoperative outcome of hip replacement.

Aged↗

Construction and evaluation of multitracer small-animal PET probabilistic atlases for voxel-based functional mapping of the rat brain.

UNLABELLED: Automated voxel-based or predefined volume-of-interest (VOI) analysis of rodent small-animal PET data is necessary for optimal use of information because the number of available resolution elements is limited. We have mapped metabolic ((18)F-FDG), dopamine transporter (DAT) (2'-(18)F-fluoroethyl(1R-2-exo-3-exe)-8-methyl-3-(4-chlorophenyl)-8-azabicyclo[3.2.1]-octane-2-carboxylate [(18)F-FECT]), and dopaminergic D(2) receptor ((11)C-raclopride) small-animal PET data onto a 3-dimensional T2-weighted MRI rat brain template oriented according to the rat brain Paxinos atlas. In this way, ligand-specific templates for sensitive analysis and accurate anatomic localization were created. Registration accuracy and test-retest and intersubject variability were investigated. Also, the feasibility of individual rat brain statistical parametric mapping (SPM) was explored for (18)F-FDG and DAT imaging of a 6-hydroxydopamine (6OHDA) model of Parkinson's disease. METHODS: Ten adult Wistar rats were scanned repetitively with multitracer small-animal PET. Registrations and affine spatial normalizations were performed using SPM2. On the MRI template, a VOI map representing the major brain structures was defined according to the stereotactic atlas of Paxinos. (18)F-FDG data were count normalized to the whole-brain uptake, whereas parametric DAT and D(2) binding index images were constructed by reference to the cerebellum. Registration accuracy was determined using random simulated misalignments and vectorial mismatching. RESULTS: Registration accuracy was between 0.24 and 0.86 mm. For (18)F-FDG uptake, intersubject variation ranged from 1.7% to 6.4%. For (11)C-raclopride and (18)F-FECT data, these values were 11.0% and 5.3%, respectively, for the caudate-putamen. Regional test-retest variability of metabolic normalized data ranged from 0.6% to 6.1%, whereas the test-retest variability of the caudate-putamen was 14.0% for (11)C-raclopride and 7.7% for (18)F-FECT. SPM analysis of 3 individual 6OHDA rats showed severe hypometabolism in the ipsilateral sensorimotor cortex (P </= 0.0004) and a striatal decrease in DAT availability (P </= 0.0005, corrected). CONCLUSION: MRI-based small-animal PET templates facilitate accurate assessment and spatial localization of rat brain function using VOI or voxel-based analysis. Regional intersubject and test-retest variations found in this study, as well as registration errors, indicate that accuracy comparable to the human situation can be achieved. Therefore, small-animal PET with advanced image processing is likely to play a useful role in detailed in vivo molecular imaging of the rat brain.

Algorithms↗

Occupation and cancer in London: an investigation into nasal and bladder cancer using the Cancer Atlas.

The Atlas of Cancer Mortality for England and Wales showed pronounced excesses of male mortality from nasal and bladder cancer in certain London boroughs. These excesses were investigated by case-referent studies using death certificate data for male deaths, 1968-78. Nasal cancer was found to be significantly associated with occupations involving heavy exposure to wood dust. Bladder cancer was significantly associated with occupations in road transport driving and in the handling of leather, whereas consistently raised relative risk ratios were also found for wood-workers, engineering fitters, printers, machinists, plumbers, and motor mechanics. These findings highlight the potential role of occupational factors in cancer causation in London.

Humans↗

Anatomical alterations of the subthalamic nucleus in relation to age: a postmortem study.

The subthalamic nucleus (STN) is currently the preferred target for chronic electrical high-frequency stimulation in Parkinson's disease. Anatomical determination of the exact position of the STN in the individual patient, using magnetic resonance imaging, remains cumbersome, whereas calculation of the target using a stereotactic atlas bypasses patient interindividual variations in the exact delineation of the STN. The aim of this study was to demonstrate variations in shape and position of the STN during life. In this anatomopathological study, a method was applied to localize the STN in reference to the anterior commissure-posterior commissure line (AC-PC line) in 12 postmortem brains of patients who died of non-neurological diseases. Their age varied from 29 to 84 years. Centers and borders of the STN were macroscopically measured in three spatial orthogonal planes in relation to the AC-PC line, and verified by light microscopy. The AC-PC distance remains almost constant during life (24.4 mm; SD 3.58). With increasing age, the center of the STN tends to move 3.9 mm cranially, 2.6 mm laterally, and 0.2 mm anteriorly. This last result also differs from the position mentioned in the stereotactic brain atlases. The form of the STN also changes. During life, the STN becomes wider in the mediolateral direction and smaller in the superior-inferior and anterior-posterior direction. The shape and spatial position of the STN also change during life. These changes should be taken into account during target determination in deep brain stimulation procedures in Parkinson's disease.

Adult↗

An atlas of the rat subpostremal nucleus tractus solitarius.

The nucleus tractus solitarius (NTS) in the dorsal medulla is the principal visceral sensory relay nucleus in the brain. In the rat, numerous lines of evidence indicate that the caudal NTS at the level of the area postrema serves as a major integrating site for coordinating cardiorespiratory reflexes and viscerobehavioral responses. This region of the caudal NTS not only exhibits high densities of binding sites for an impressive array of transmitters and modulators but microinjections of many of these same neuroactive substances into the rat subpostremal NTS elicit pronounced cardiorespiratory and visceral response patterns. This report provides an abbreviated atlas of the rat subpostremal NTS consisting of a series of transverse, sagittal, and horizontal plates. Photomicrographs, together with their corresponding schematic drawings, are provided for the serial sections generated from each reference plane.

Animals↗

A stereotaxic atlas of the forebrain of the bank vole (Clethrionomys glareolus).

In this article part of the forebrain of the bank vole (Clethrionomys glareolus) is presented in stereotaxic coordinates. The stereotaxic procedure was performed as follows. With the vole's head mounted in a stereotaxic adaptor, internal reference tracks were made with a 0.5-mm diameter microdialysis cannula and India ink, 2 mm in front and 2.6 mm behind the skull landmark bregma. Brains were fixed for 72 h in 4% commercial formaldehyde in sodiumcacodylate buffer containing 1% CaCl2. To determine shrinkage they were weighed before and after fixation. After embedding in paraffin they were sectioned at 25 microm and stained with Nissl. Photomicrographs were taken from the brain of one animal while its frontal (antero-posterior) coordinates of five neural structures were compared with those of 12 other voles. Variability was also checked in lateral and vertical directions at frontal level -1.0 mm (relative to bregma). The results show that the distance between the two skull landmarks bregma and lambda correlates significantly and negatively with the antero-posterior position of each of the brain areas. On the basis of these results an equation is proposed to improve accuracy in locating neural structures that deviate due to biological variability.

Animals↗

Embryonic and posthatching development of the barn owl (Tyto alba): reference data for age determination.

The normal development of the barn owl was documented with the intent of providing a guideline for determining the maturational stage of embryos and posthatching individuals. Embryonic development up to stage 39 could be well described using the well-known developmental atlas for the chicken (Hamburger and Hamilton [1951] J. Morphol. 88:49-92). For later stages, limb size was established as a suitable indicator. In addition, measuring the egg's vascularized area through candling was found to be a useful, noninvasive method for staging very early embryos, up to stage 25. An average relationship between incubation period and embryonic stage was derived, which showed that development in the barn owl initially lags that in the chicken. For posthatching individuals, skeletal measures (tarsal and ulnar length, skull width and length) were the most reliable parameters for judging maturation, up to 1 month. For older individuals, feather development (e.g., length of primary wing feathers) provided the only cue.

Age Factors↗

A gene expression map of Arabidopsis thaliana development.

Regulatory regions of plant genes tend to be more compact than those of animal genes, but the complement of transcription factors encoded in plant genomes is as large or larger than that found in those of animals. Plants therefore provide an opportunity to study how transcriptional programs control multicellular development. We analyzed global gene expression during development of the reference plant Arabidopsis thaliana in samples covering many stages, from embryogenesis to senescence, and diverse organs. Here, we provide a first analysis of this data set, which is part of the AtGenExpress expression atlas. We observed that the expression levels of transcription factor genes and signal transduction components are similar to those of metabolic genes. Examining the expression patterns of large gene families, we found that they are often more similar than would be expected by chance, indicating that many gene families have been co-opted for specific developmental processes.

Arabidopsis↗

Evaluation of extracranial vertebral artery dissection with duplex color-flow imaging.

BACKGROUND AND PURPOSE: We describe the diagnostic potential of duplex color-flow imaging in the evaluation of extracranial vertebral artery dissection. METHODS: Twenty patients with 24 extracranial vertebral artery dissections (four bilateral) were examined with duplex ultrasonography over a period of 6 years. Color-flow imaging was carried out in 16 of these patients. In 15 patients (75%), the dissection was temporally related to trauma. Angiography was available in 18 patients, confirming the diagnosis. RESULTS: In 15 patients, the diagnosis was primarily established with ultrasonography. Five patients with a dissection were referred for follow-up color-flow examinations. Six vertebral arteries were dissected at the origin or in the proximal V1 segment, one in the distal V2 segment, and one at the atlas loop. In contrast to other studies, the most frequent localization of the dissection in our patients was the region between the V1 and V2 segments (n = 16), where the most typical dissection site was the entrance of the artery into the transverse foramen of the C6 vertebra (n = 11). Typical ultrasonographic findings were irregular stenosis, dissecting membrane with true and false lumen, localized increase in diameter of the artery, pseudoaneurysm, intramural hematoma, and tapering stenosis with distal occlusion. In follow-up examination, a good regression of pathological findings was found in 17 dissections (70.8%). Two occlusions were completely recanalized. CONCLUSIONS: Extracranial vertebral artery dissections can be diagnosed noninvasively with duplex color-flow imaging. It is therefore a useful method for early diagnosis and follow-up examination.

Adolescent↗

Stature and skeletal maturation of two cohorts of Australian children and young adults over the past two decades.

BACKGROUND: Assessment of growth and maturation in humans has implications in the diagnosis and treatment of growth disorders and in determining timing of orthopaedic interventions. AIMS: Our aims were to investigate whether there was evidence of recent secular changes in stature and skeletal maturation in Australians, and to report any association between these parameters. METHODS: The cross-sectional study sample comprised 5,122 South Australian children and young adults, including 2,601 males and 2,521 females aged between 9 and 18 years. Records obtained from 1987 to 2005 included chronological age, stature and skeletal age in these individuals. Centiles for stature were calculated using the National Health and Medical Research Council of Australia (NHMRC) growth references published in 1975. Stature was measured to the nearest 0.1 cm and the developmental stages of strategic ossification centres on hand-wrist radiographs were evaluated using the Greulich and Pyle (1959) atlas method. RESULTS: Average values for stature were consistently greater in the 1995-2005 cohort compared with the 1987-94 cohort for both sexes, although secular increases in females were less prominent compared with males. Males in the 1995-2005 cohort were also skeletally advanced when compared with their counterparts in the 1987-94 cohort, but this trend was not evident in females. There were significant associations between stature and skeletal maturation, with the strongest associations being noted around puberty in both sexes and progressively weaker associations in older age groups. CONCLUSION: Our findings indicate secular increases in stature in Australian children and young adults of both sexes over the past few decades, and acceleration of skeletal maturation in males.

Adolescent↗

A method for assessing the significance of abnormalities in HMPO brain SPECT images.

METHODS: A normal atlas for HMPAO rCBF SPECT images was obtained from images of 53 normal controls. Following image registration and normalization, a mean image was extracted, while images representing correlated normal deviants were identified using principal component analysis. These images formed the "building blocks" of the atlas. For subsequent images, the atlas was used to create a "nearest normal equivalent" image, which was compared to a residual standard deviation image to determine the significance of deviations in the new image. RESULTS: Images from 30 patients (10 with Alzheimer's disease; 12 with single or multiple infarcts; and 8 normals) were analyzed. CONCLUSION: Using an optimal decision level, 10/10 patients with Alzheimer's disease and 11/12 patients with infarcts were correctly identified, with only one false-positive resulting. We utilized a database of images obtained from normal controls to create a normal atlas.

Alzheimer Disease↗

A three-gene radioresistance signature predicts tumor progression in cervical cancer.

BACKGROUND: As a primary curative treatment for locally advanced cervical cancer, radiotherapy is frequently undermined by radioresistant tumor cells that evade cell death and subsequently drive post-treatment tumor progression. This study aimed to identify candidate genes associated with radioresistance in cervical cancer and to explore their potential in predicting unfavorable outcomes among radioresistant patients, thereby providing a reference for future research. METHODS: We screened for co-expressed genes using transcriptomic data from radiation non-complete response (NCR) cervical cancer patients in Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases. Cox regression analyses were conducted to identify the most significant radioresistance-associated genes for constructing a prognostic model. The predictive performance of this model was further validated through logistic regression, weighted gene co-expression network analysis (WGCNA), and pan-cancer analyses. Quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) was performed to quantify the expression levels of key genes in cervical cancer tissue samples from radiosensitive and radioresistant patients. RESULTS: The resulting prognostic model comprised three genes: MTMR11, VANGL1, and CD46. This gene panel was significantly associated with the prognosis of cervical cancer patients receiving radiotherapy and showed acceptable predictive performance across multiple cancer types. qRT-PCR analysis revealed that the expression patterns of MTMR11 and VANGL1 were generally consistent with radioresistance of cervical cancer, whereas CD46 exhibited an unexpected expression trend. CONCLUSIONS: Our findings indicate that MTMR11, VANGL1, and CD46 are associated with radioresistance and prognosis in cervical cancer. Their potential clinical utility, especially in predicting radiotherapy response at the individual patient level, requires further validation in larger, independent, and prospective cohorts.

Cervical cancer↗

The role of Adam Politzer (1835-1920) in the history of otology.

PURPOSE: To study and understand the contribution made by Adam Politzer (1835-1920) to 20th century otology and analyze his place in the history of otology. METHOD: A study of his four reference works, some of his hundreds of publications in medical journals, and diverse publications written about him. RESULTS: All areas of otology have been studied, compiled, and improved through his assorted publications, notably his atlas of otoscopy published in 1865, the first work of its kind, expanded and reedited in 1896; his 10 tables of the anatomy of the ear amended in 1873; his textbook of the diseases of the ear, which was first published in two volumes in 1878 and 1882 and subsequently reedited four times as one volume, the last time being in 1908; his anatomy and histology book published in 1889; and his book on the history of otology, which up to now is the most complete tome existing on the subject, edited in two volumes in 1907 and 1913. No other has been as prolific as he. He invented, in particular, a revolutionary method of making the eustachian tube permeable--a method that made him famous and carries his name. He also developed an acoumeter to measure hearing and was the first to describe certain pathologic conditions histologically, of which otosclerosis is one. CONCLUSION: Politzer is certainly the greatest otologist of the 19th century and probably one of the greatest of all time. His influence on the 50 years of otology has never been equaled. He deserves a double mention in the history of otology: as an otologist and as a historian. It is in his honor that the International Society of Otology bears his name.

Anatomy, Artistic↗

[Avoidable deaths in the evaluation of the performance of health services. II. European Atlas of avoidable deaths: initial data and several reflections].

The second European Atlas of Avoidable deaths, which will be shortly issued, concerns the period 1979-83 for Italy. The causes of deaths included were: tuberculosis, neoplasms of the cervix uteri and those of the uterus with no specified site, Hodgkin's disease, chronic rheumatic heart disease, hypertensive and cerebrovascular disease, childhood respiratory infections, asthma, appendicitis, abdominal hernia, cholecystitis and cholelithiasis, maternal and perinatal deaths. In Italy marked excesses for cholecystitis-cholelithiasis, Hodgkin's disease, hypertensive and cerebrovascular disease and perinatal mortality were observed. A remarkable decrease was observed in comparison with the first Atlas (1974-78); but the European countries generally maintained the differences amongst them and their rank. Proposals to assess the causes of the observed differences are suggested (death certificate quality evaluation studies, case-reference studies, cohort studies) and the role of confidential enquiries is discussed.

Adolescent↗

Characterisation of size and direction of osteophyte in knee osteoarthritis: a radiographic study.

OBJECTIVES: To examine the size and direction of osteophyte in knee osteoarthritis (OA) and to determine associations between osteophyte size and other radiographic features. METHODS: Knee radiographs (standing extended anteroposterior and 30 degrees flexion skyline views) were examined from 204 patients referred to hospital with symptomatic knee OA (155 women, 49 men; mean age 70, range 34-91 years). A single observer assessed films for osteophyte size and direction at eight sites; narrowing in each compartment; varus/valgus angulation; patellofemoral subluxation; attrition; and chondrocalcinosis using a standard atlas, direct measurement, or visual assessment. For analysis, one OA knee was selected at random from each subject. RESULTS: Osteophyte direction at the eight sites was divisible into five categories. At all sites, except for the lateral tibial plateau and the medial patella, osteophyte direction varied according to (a) the size of osteophyte and (b) the degree of local narrowing. At the medial femur, medial tibia, and lateral femur osteophyte direction changed from being predominantly horizontal to predominantly vertical with increasing size. The size of osteophyte correlated positively with the severity of local narrowing, except for the medial patellofemoral compartment where osteophyte size correlated positively with the severity of narrowing in the medial tibiofemoral compartment. Logistic regression analysis showed that osteophyte size was associated not only with local narrowing but also with local malalignment and bone attrition, and that chondrocalcinosis was positively associated with osteophyte size at multiple sites. CONCLUSION: In patients referred to hospital with knee OA different patterns of osteophyte direction are discernible. Osteophyte size is associated with local compartmental narrowing but also local alignment and attrition. Chondrocalcinosis is associated with osteophytosis throughout the joint. These data suggest that both local biomechanical and constitutional factors influence the size and direction of osteophyte formation in knee OA.

Adult↗

Genomic introgressions from wild relatives in the wheat genome alter meiotic dynamics in inter-varietal hybrids.

The use of wild relatives to introduce original diversity in the genome of bread wheat (Triticum aestivum L.) is an interesting approach to face the challenges of sustainable agriculture and the impact of climate change on wheat production. However, the influence of these wild-species introgressions on meiosis in inter-varietal wheat hybrids remains poorly understood. We analyzed the French wheat variety Renan (Re) carrying Aegilops ventricosa (Aev)-derived 2AS/2NS and 7DL/7DvL introgressions, the reference cultivar Chinese Spring (CS), which lacks these introgressions, and their inter-varietal hybrid Chinese Spring &#xd7; Renan (CSRe). This analysis combined cytogenetic approaches with the assessment of reproductive performance. Furthermore, we generated a cytological atlas of meiosis in wild tetraploid Aev, quantifying bivalent configurations and chiasma frequency. We observed a reduced pollen viability and a slight decrease in floret fertility in the hybrid CSRe. Exploration of the meiotic behavior showed that CSRe exhibited increased numbers of rod bivalents and univalents, leading to a reduced average chiasma number and frequent chromosome bridges and fragmentations, whereas the parental lines maintained stable chromosome pairing. These rearrangements indicate that homologous chromosome pairing and recombination are affected in CSRe. We applied introgression-specific oligo-Fluorescent In Situ Hybridization to localize alien segments in CSRe, providing a novel strategy to investigate the meiotic behavior of introgressed regions. The 2AS/2NS introgressed segments in CSRe were frequently located on rod bivalents or univalents, while 7DL/7DvL segments consistently formed ring bivalents. Our results provide a foundation for guiding alien gene introgression and for understanding the behavior of chromosomes with introgressions in the wheat genome.

Meiosis↗

Virtual laboratory manual for microscopic anatomy.

Using digital technology, we have assembled a virtual laboratory manual (VLM) that is a Web-based copy of our traditional laboratory manual. The VLM is used to enhance traditional laboratory instruction in histology. For each reference in the VLM to either a histological slide or an electron micrograph (EM), hyperlinks are included that download digital images derived from the students' glass slide sets or scanned EMs. The VLM serves as an atlas of digital images for concurrent study of similar sections by light microscopy during laboratory sessions. In addition, students can review the images from the VLM at remote locations. We have encouraged continued use of light microscopes in laboratories by basing the majority of practical examination identifications on analysis of marked histological slides that require students to use their own microscopes. The VLM provides the convenience of a Web-based resource with high-quality images, yet allows retention of the many excellent traditional aspects of our course. An example of a VLM laboratory on epithelium is available online (http://users.von.uc.edu/michaeje/VLM-Epithelium/exLab4.pdf).

Computer-Assisted Instruction↗