ABSTRACT
Phylogenetic diversity indices are commonly used to rank the elements in a collection of species or populations for conservation purposes. The derivation of these indices is typically based on some quantitative description of the evolutionary history of the species in question, which is often given in terms of a phylogenetic tree. Both rooted and unrooted phylogenetic trees can be employed, and there are close connections between the indices that are derived in these two different ways. In this paper, we introduce more general phylogenetic diversity indices that can be derived from collections of subsets (clusters) and collections of bipartitions (splits) of the given set of species. Such indices could be useful, for example, in case there is some uncertainty in the topology of the tree being used to derive a phylogenetic diversity index. As well as characterizing some of the indices that we introduce in terms of their special properties, we provide a link between cluster-based and split-based phylogenetic diversity indices that uses a discrete analogue of the classical link between affine and projective geometry. This provides a unified framework for many of the various phylogenetic diversity indices used in the literature based on rooted and unrooted phylogenetic trees, generalizations and new proofs for previous results concerning tree-based indices, and a way to define some new phylogenetic diversity indices that naturally arise as affine or projective variants of each other or as generalizations of tree-based indices.
Subject(s)
Biodiversity , Phylogeny , Models, Genetic , Mathematical Concepts , Biological Evolution , AnimalsABSTRACT
In the present study, our aim was to investigate whether the novel highly selective 5-hydroxytryptamine6 (5-HT6) receptor antagonist SLV can ameliorate impairments in cognition and social interaction with potential relevance for both schizophrenia and Alzheimer's disease (AD). SLV sub-chronically - treated Wistar rats reared in isolation showed significantly enhanced prepulse inhibition (PPI) and object recognition performance when compared to vehicle - treated rats. In the isolated rats, also a significant reduction in expression of hippocampal neural cell adhesion molecule polysialylation (NCAM-PSA) was found which was ameliorated following treatment with SLV (30mg/kg). The social engagement deficit in rats exposed in utero (on gestational day 12.5) to valproic acid (VPA) was reversed by treatment with SLV (30mg/kg). SLV (20 and 30mg/kg, p.o.) fully reversed MK-801 - induced deficits in the ORT and also scopolamine - induced deficits in both the Object Recognition Task (ORT) and Object Location Task (OLT) in Wistar rats. In addition, a combination of sub-optimal doses of SLV and donepezil attenuated scopolamine-induced ORT deficits. Furthermore, SLV (10mg/kg, p.o.) reversed spontaneous alternation deficits in the T-maze induced by MK-801 administration in Swiss mice and in aged C57Bl/6J mice. SLV additionally improved T-Maze spatial learning and passive avoidance learning in Sprague-Dawley rats with amyoid-beta (Aß) injections into the hippocampus. In contrast, no benefits were found with SLV or the tested reference compounds (donepezil and RVT-101) on cognitive performance of 12months old Tg2576 mice. Also, in the social recognition task, an absence of cognitive enhancing properties was observed with SLV on "normal forgetting" in Wistar rats. Finally, analysis of spontaneous inhibitory postsynaptic currents (sIPSCs) frequency recorded from pyramidal cells revealed a reduction in the presence of 1µM of SLV. In conclusion, SLV was investigated in several rodent animal models and found to be effective at a least effective dose (LED) of 20mg/kg and 10mg/kg (p.o.) in the rat and the mouse, respectively.
Subject(s)
Behavior, Animal/drug effects , Cognitive Dysfunction/drug therapy , Hippocampus/drug effects , Inhibitory Postsynaptic Potentials/drug effects , Maze Learning/drug effects , Prenatal Exposure Delayed Effects/drug therapy , Prepulse Inhibition/drug effects , Pyramidal Cells/drug effects , Receptors, Serotonin , Recognition, Psychology/drug effects , Serotonin Antagonists/pharmacology , Social Perception , Age Factors , Animals , Female , Male , Mice , Mice, Inbred C57BL , Pregnancy , Rats , Rats, Sprague-Dawley , Rats, Wistar , Serotonin Antagonists/administration & dosageABSTRACT
BACKGROUND AND PURPOSE: Alzheimer's disease (AD) is a multifactorial, neurodegenerative disease, which is in part caused by an impairment of synaptic function, probably mediated by oligomeric forms of amyloid-beta (Abeta). While the Abeta pathology mainly affects the physiology of neurotransmission, neuronal decline is caused by excitotoxic cell death, which is mediated by the NMDA receptor. A comprehensive therapeutic approach should address both Abeta-induced synaptic deficits, as well as NMDA receptor-mediated neurodegeneration, via one molecular target. This study was designed to test whether calpain could be involved in both pathological pathways, which would offer a promising avenue for new treatments. EXPERIMENTAL APPROACH: Application of the specific, water-soluble calpain inhibitor A-705253 was used to inhibit calpain in hippocampal slice cultures. We examined whether inhibition of calpain would prevent Abeta-induced deficits in neurotransmission in CA1, as well as NMDA-induced neuronal cell death. KEY RESULTS: A-705253 dose-dependently prevented excitotoxicity-induced neurodegeneration at low nanomolar concentrations, determined by propidium iodide histochemistry. Inhibition of the NMDA receptor similarly protected from neuronal damage. Caspase staining indicated that calpain inhibition was protective by reducing apoptosis. Electrophysiological analysis revealed that inhibition of calpain by A-705253 also fully prevented Abeta oligomer-induced deficits in neurotransmission. The protective effect of calpain was compared to the clinically available NMDA receptor antagonist memantine, which was also effective in this model. CONCLUSIONS AND IMPLICATIONS: We suggest that inhibition of calpain exhibits a promising strategy to address several aspects of the pathology of AD that may go beyond the available therapeutic intervention by memantine.
Subject(s)
Amyloid beta-Peptides/metabolism , Benzamides/pharmacology , Calpain/antagonists & inhibitors , Cell Death/drug effects , Hippocampus/drug effects , N-Methylaspartate/pharmacology , Synapses/drug effects , Animals , Hippocampus/physiopathology , In Vitro Techniques , Male , Rats , Rats, Wistar , Synapses/physiology , Synaptic TransmissionABSTRACT
One of the hallmarks of Alzheimer's disease is the accumulation of amyloid plaques in brains of affected patients. Several recent studies provided evidence that soluble oligomer forms of amyloid-beta (Abeta) rather than plaques determine cognitive decline. In vitro studies using artificial Abeta oligomer preparations suggest that such pathophysiology is caused by a specific impairment of synaptic function. We examined whether synaptic deficits occur before deposition of insoluble fibrillar Abeta by analyzing brain slices taken from young Tg2576 mice overexpressing mutant amyloid precursor protein. Excitatory synaptic transmission in the hippocampal CA1 region was strongly impaired before plaque development, suggesting a dissociation of an early synaptic impairment, probably caused by soluble oligomeric amyloid-beta, from subsequent plaque formation. At higher age neurotransmission was also decreased in wild type mice, paralleling a cognitive decline of normal aged animals. Memory formation in rats is accompanied by distinct hippocampal network oscillations. It has recently been shown that hippocampal gamma oscillations, a network correlate of exploratory behavior, are impaired in amyloid precursor protein (APP)-overexpressing mice. We determined whether sharp wave-ripple complexes, which contribute to memory consolidation during slow wave-sleep, are modified in Tg2576 mice. Interestingly, neither sharp waves nor superimposed ripples were changed at pre-plaque or plaque stages. During aging, however, there was a strong reduction of sharp wave frequency and ripple energy in wild type and APP-overexpressing animals. This indicates that the reported changes in network oscillations following APP-overexpression are specific for gamma oscillations, whereas aging has a more general effect on network properties. Taken together our data suggest that non-fibrillar forms of Abeta--possibly Abeta oligomers--specifically interfere with synaptic function in Tg2576, but do not globally alter memory-related network properties. We propose that mechanisms leading to Abeta-related cognitive decline are different from those related to aging.
Subject(s)
Aging/physiology , Amyloid beta-Protein Precursor/genetics , Behavior, Animal , Excitatory Postsynaptic Potentials , Plaque, Amyloid/pathology , Synaptic Transmission , Amyloid beta-Protein Precursor/biosynthesis , Animals , Female , Hippocampus/pathology , Hippocampus/physiopathology , Humans , In Vitro Techniques , Memory , Mice , Mice, TransgenicABSTRACT
Serotonin 5-HT1A and 5-HT1B/1D receptors control serotonin (5-HT) release and are targets for the pharmacological treatment of psychiatric disorders. We investigated effects of the 5-HT1B/1D antagonist GR127935, the 5-HT1A antagonist WAY 100635 and a combination of both in guinea pigs on the behaviour in the forced swimming test and on extracellular 5-HT in the hippocampus and the prefrontal cortex using in vivo microdialysis. Tissue content of 5-HT, 5-HIAA and 5-HT turnover (ratio 5-HIAA/5-HT) were determined in a sample containing i) the median and dorsal raphe nuclei, ii) the frontal cortex, or iii) the ventral hippocampus ex vivo. BEHAVIOUR: Administration of WAY 100635 (0.3-3.0 mg/kg, i.p.) or GR127935 (1.0-10.0 mg/kg, i.p.) or the combination of both delayed immobility in the forced swim test. MICRODIALYSIS: Systemic administration of WAY 100635 (1 mg/kg i.p.), perfusion with GR127935 (10 microM perfused into the frontal cortex) in the medial prefrontal cortex or the combination of both treatments had no significant effect on extracellular 5-HT. 5-HT TISSUE CONTENT AND 5-HT TURNOVER IN THE TISSUE: Compared to controls, WAY 100635, GR127935 and the combination thereof, decreased cortical 5-HT (-30%), increased 5-HIAA and consequently 5-HT turnover in the cortex threefold and the raphe nuclei twofold. WAY 100635 decreased 5-HT in the hippocampus (-40%), too. WAY 100635 and GR127935 and their combination increased hippocampal 5-HIAA and 5-HT turnover twofold, compared to controls. The results suggest that both 5-HT1 antagonists have subtle effects on 5-HT function under resting conditions; combined treatment has no superior effects compared to solitary treatment.
Subject(s)
Behavior, Animal/drug effects , Receptor, Serotonin, 5-HT1A/drug effects , Receptor, Serotonin, 5-HT1B/drug effects , Receptor, Serotonin, 5-HT1D/drug effects , Serotonin Antagonists/pharmacology , Animals , Brain Chemistry/drug effects , Depression/psychology , Female , Guinea Pigs , Hydroxyindoleacetic Acid/metabolism , Microdialysis , Oxadiazoles/pharmacology , Piperazines/pharmacology , Pyridines/pharmacology , Serotonin/metabolism , Swimming/psychologyABSTRACT
Recent studies have fueled the interest in dopamine D3 receptor antagonists and partial agonist for the treatment of psychosis and drug abuse, respectively. N-[4-[4-(2-methoxyphenyl)-1-piperazinyl]butyl]naphthalene-2-carboxamide (BP 897) is a dopamine D3 receptor selective ligand recently described as partial agonist with potential effects on drug-dependence. The aim of the present study was to determine both the functional activity of BP 897 at human dopamine D3 receptors expressed in Chinese hamster ovary (CHO) cells and in an electrophysiological in vivo model of dopaminergic activity. BP 897 failed to stimulate the human dopamine D3 receptor and showed antagonistic effects (cpIC(50)=9.51) in a [(35)S]GTPgammaS binding assay in cells expressing the human dopamine D3 receptor. In vivo, BP 897 up to 8.2 mg/kg, i.v., had no agonistic effects on firing rate of substantia nigra dopaminergic neurons and antagonized the quinpirole-induced inhibition of firing (DID(50)=1.1 mg/kg). Our data demonstrate that BP 897 acts, in vivo and in vitro, as a dopamine D3 receptor antagonist.
Subject(s)
Dopamine Agonists/pharmacology , Dopamine Antagonists/pharmacology , Dopamine D2 Receptor Antagonists , Piperazines/pharmacology , Animals , Benzopyrans/pharmacology , Binding, Competitive/drug effects , CHO Cells , Cricetinae , Dendrites/drug effects , Dendrites/metabolism , Dopamine/pharmacology , Dose-Response Relationship, Drug , Electrophysiology , Guanosine 5'-O-(3-Thiotriphosphate)/metabolism , Humans , Male , Neurons/drug effects , Neurons/physiology , Oxazines/pharmacology , Quinpirole/pharmacology , Rats , Rats, Sprague-Dawley , Receptors, Dopamine D2/agonists , Receptors, Dopamine D2/metabolism , Receptors, Dopamine D3 , Substantia Nigra/drug effects , Substantia Nigra/metabolism , Sulfur Radioisotopes , Tetrahydronaphthalenes/pharmacologyABSTRACT
In the mammalian mesencephalon, virtually all serotoninergic neurons are located in the raphe nuclei and the adjacent reticular formation. Pharmacological evidence obtained in rodents suggests that terminal and somatodendritic autoreceptors controlling serotonin (5-hydroxytryptamine, 5-HT) release belong to the 5-HT1B/D subtype of receptors, whereas somatodendritic autoreceptors controlling neuronal cell firing are predominantly of the 5-HT1A subtype. This study investigated the presence of h5-HT1D and h5-HT1B receptor mRNA within the subdivisions of the dorsal raphe of post-mortem human brains by means of in situ hybridisation. Although differences in the labelling intensity, which may be caused by different pre- and/or post-mortem conditions, were obvious among the specimens, all brains expressed both the h5-HT1D and the h5-HT1B mRNA in dorsal raphe neurons. In comparison to h5-HT1D mRNA, expression of h5-HT1B mRNA was slightly more abundant. Information on the existence and localisation of h5-HT1D and h5-HT1B receptors in human dorsal raphe neurons confirms that both subtypes may serve an autoreceptor function in humans. This finding is of pharmacological relevance since these receptors are potential new targets for therapeutic interventions in psychiatric disorders such as depression and anxiety.
Subject(s)
RNA, Messenger/biosynthesis , Raphe Nuclei/metabolism , Receptors, Serotonin/genetics , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Neurons/metabolism , Raphe Nuclei/cytology , Receptor, Serotonin, 5-HT1B , Receptor, Serotonin, 5-HT1DABSTRACT
The consequences of a single bout of heavy eccentric exercise with and without repeated concentric exercises on MRI images, serum CK levels and markers of inflammation were studied. Two groups (ECC and ECCON), each consisting of 18 male volunteers, performed 70 eccentic contractions of the quadriceps femoris muscle. The study group (ECCON) performed additional concentric contractions on a dynamometer (Cybex II+) one day before and two hours, 1, 2, 3, 6 and 9 days after eccentric loading. Serum levels of creatine kinase (CK) were examined as a function of time, and correlated with measurements of magnetic resonance imaging (MRI) of the involved muscle groups. T2-weighted images of the thigh muscles were studied. Serum C-reactive protein, complement factors C3c and C4, haptoglobin and transferrin were measured as markers of inflammation. Additional concentric contractions (ECCON group) significantly increased CK, compared to the ECC group. However, it has no apparent effect on MRI signal intensity changes, which were of equal magnitude in the loaded vastus intermedius and deep parts of the vastus lateralis in both groups. Likewise, the serum markers of inflammation of the exercised muscles appeared to be absent. Based on MRI-images, additional concentric contractions had no statistically significant effect on muscle damage and breakdown of connective tissue. The five-fold increase in CK in the ECCON group could be a reflection of "massaging out" of the CK from the muscles into the circulation by additional concentric exercises. However, it could also be an indication for a superior sensitivity of assessing muscle fiber damage in comparison to the MRI.
Subject(s)
Creatine Kinase/blood , Exercise/physiology , Muscle Contraction/physiology , Muscle, Skeletal/pathology , Adult , Humans , Inflammation , MaleABSTRACT
In a 39-year-old man an isolated, unruptured extracardiac aneurysm of the left sinus of Valsalva led to almost complete rarefication of one aortic valve leaflet, causing insufficiency of the valve. At operation the aneurysm entrance was closed with a patch and prosthetic replacement of the bicuspid aortic valve was performed. The result was satisfactory.
Subject(s)
Aortic Aneurysm/complications , Aortic Valve Insufficiency/etiology , Aortic Valve/abnormalities , Sinus of Valsalva , Adult , Aortic Aneurysm/diagnostic imaging , Aortic Aneurysm/surgery , Aortic Valve/surgery , Aortic Valve Insufficiency/diagnostic imaging , Aortic Valve Insufficiency/surgery , Heart Valve Prosthesis , Humans , Male , Radiography , Sinus of Valsalva/diagnostic imagingABSTRACT
PURPOSE: In September 1991, a mummified corpse was discovered soon after it was released by the receding ice of the Similaun glacier in the Tyrolean Alps. This body proved to be an astonishingly well-preserved man from the late Neolithic Age or early Bronze Age. To preserve the fragile mummy, scientific investigations were required to be as noninvasive and nondestructive as possible. MATERIALS AND METHODS: A radiologic investigation that included conventional radiography, digital radiography, and whole-body computed tomography (CT) was performed from the CT data, the skull was duplicated by means of stereolithography. RESULTS: The copy of the prehistoric skull was validated by means of comparison of measurements obtained from the original CT images and from external physical measurements of the intact head of the mummy. CONCLUSION: The CT images, radiologic findings, and duplicated skull are expected to provide anthropologists and other interested scientists relatively accurate information without the need to handle the mummy, to expose it to the considerable risks of repeated partial thawing, or to perform invasive exploratory studies such as autopsy.
Subject(s)
Hominidae/anatomy & histology , Mummies , Skull/diagnostic imaging , Tomography, X-Ray Computed , Animals , Austria , Cephalometry , Computer Simulation , Freezing , History, Ancient , Humans , Image Processing, Computer-Assisted , Italy , Male , Mummies/diagnostic imaging , Skull/anatomy & histologyABSTRACT
As early as 1974, Brian advocated the prone position for ventilated patients. He suggested that this position might enhance ventilation of the dorsal parts of the lungs, thereby improving oxygenation. These considerations have been confirmed by several experimental and clinical studies. Better secretion removal, decreased intrapulmonary shunting, and an increased FRC are thought to be responsible for the observed improvement of oxygenation. However, the prone position never became very popular in the clinical treatment of the adult respiratory distress syndrome (ARDS). Routine performance of thoracic CT scans in ARDS patients demonstrated preferential distribution of pathological densities in the dependent lung areas. The prone position therefore could possibly benefit these patients, as shown by two recent studies. The aim of our study was to evaluate the influence of repeatedly turning the patient to the prone position on gas exchange and thoracic CT findings in multiple-trauma patients. METHODS. Seven ventilated intensive care patients with severe ARDS (Murray Score > 2.5, Quotient > 0.7, mean airway pressure > 18 cm H2O, thoracic CT scan showing dorsal atelectases) were included in the study. Patients were turned from the supine to the prone position at 12-h intervals using an air-cushion bed (Mediscus, Austria). Redistribution of dystelectatic or atelectatic dependent lung areas was verified by means of repeated thoracic CT scans (Figs. 1, 8). RESULTS. The patients were intermittently turned for 6.5 +/- 1.1 days. The course of gas exchange is shown in Figs. 2 and 3. Initially, improvement of the respiratory quotient could only be achieved during prone positioning, from the 2nd day in the supine position as well. Intrapulmonary shunting showed a similar trend (Figs. 4 and 5). No significant changes in cardiovascular parameters could be observed. Control thoracic CT scans showed uniform reduction of atelectases in dependent lung areas (Figs. 1 and 8). The inspiratory fraction of oxygen could be reduced significantly as of the 2nd day (Fig. 7). Constant levels of positive end-expiratory pressure and tidal volume were associated with decreasing mean and plateau airway pressures (Fig. 6). DISCUSSION. Repeatedly turning the patient to the prone position produced long-lasting improvement of arterial oxygenation, which persists up to the end of the weaning process. This is in good accordance with other studies, however, this is the first study to report an observation period of more than 6 days of repeatedly turning the patient. These positive effects on gas exchange can be attributed to sudden improvement of the ventilation-perfusion ratio within the lung areas that become dependent after turning to the prone position. Due to reduced hydrostatic pressure and relative hyperventilation, previously collapsed alveoli are recruited in the lung areas that become non-dependent after turning to the prone position.
Subject(s)
Prone Position , Respiratory Distress Syndrome/therapy , Adult , Humans , Middle Aged , Multiple Trauma/complications , Pulmonary Atelectasis/therapy , Pulmonary Gas Exchange/physiology , Respiration, Artificial , Respiratory Distress Syndrome/diagnostic imaging , Respiratory Distress Syndrome/physiopathology , Respiratory Function Tests , Tomography, X-Ray ComputedABSTRACT
We report a 42-year-old HIV-negative patient with a 12-year history of exceptionally extensive genital warts and coexisting verrucous carcinoma of the anogenital region (Buschke-Loewenstein tumour). Masses of both tumour and viral papillomas infiltrated the external genitalia, perineum and buttocks, pelvic diaphragm and parts of the lesser pelvis, as well as the urethra, prostate and parts of the urinary bladder, necessitating repeated surgical intervention and plastic reconstruction. Adjuvant interferon-alpha therapy was given without any lasting effects. Human papillomavirus type 6 was detected by DNA in situ hybridization and Southern blot analysis.
Subject(s)
Anus Neoplasms/pathology , Carcinoma, Verrucous/pathology , Condylomata Acuminata/pathology , Genital Neoplasms, Male/pathology , Adult , Anus Neoplasms/microbiology , Carcinoma, Verrucous/microbiology , Genital Neoplasms, Male/microbiology , Humans , Male , Neoplasm Invasiveness , Papillomaviridae/isolation & purification , Rectal Neoplasms/microbiology , Rectal Neoplasms/pathology , Urinary Bladder Neoplasms/microbiology , Urinary Bladder Neoplasms/pathologySubject(s)
Anal Canal/physiopathology , Defecation/physiology , Gastrointestinal Transit/physiology , Rectum/physiopathology , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle AgedABSTRACT
CT-guided stereolithography provides an acrylic model which exactly replicates the original structure. It allows optimal preoperative planning and intraoperative management. This application proved advantageous in surgical correction of a wide midline craniofacial cleft in a baby.
Subject(s)
Facial Bones/abnormalities , Models, Anatomic , Nose/abnormalities , Skull/anatomy & histology , Tomography, X-Ray Computed , Face/abnormalities , Face/surgery , Facial Bones/surgery , Female , Humans , Infant , Mummies/pathology , Skull/abnormalities , Skull/surgery , Surgery, PlasticABSTRACT
In a retrospective study of 1230 patients with blunt abdominal or flank trauma, the results of microscopic urinalysis, urography, sonography, and computed tomography in the diagnosis and staging of renal injuries were compared. Haematuria was present in 98% of renal lacerations and in all pedicle injuries, whereas among 1038 patients without haematuria only one small laceration was found. The degree of haematuria showed no correlation with the severity of renal injury. 92 renal injuries were diagnosed radiologically, including 58 lacerations, 31 contusions, and three pedicle injuries. Computed tomography was performed in 39 lacerations and six contusions, and allowed correct diagnosis and staging in all cases. Urography established the correct diagnosis in 72%, and sonography in 85%. Sensitivity in the diagnosis of clinically relevant injuries (lacerations and pedicle injuries) was 98% (specificity: 99%), when both modalities were combined. Based on the results of our study, we suggest the use of sonography as a screening modality in blunt abdominal or flank trauma, and additional urography in case of haematuria. Computed tomography is the method of choice for exact staging of suspected renal injury.
Subject(s)
Kidney/injuries , Wounds, Nonpenetrating/diagnosis , Adolescent , Adult , Aged , Child , Female , Humans , Kidney/diagnostic imaging , Male , Middle Aged , Retrospective Studies , Tomography, X-Ray Computed , Ultrasonography , Urinalysis , Urography , Wounds, Nonpenetrating/epidemiologyABSTRACT
The value of magnetic resonance imaging (MRI) was studied in a case of a gestational trophoblastic tumour. In addition to the tumour size, MRI made it possible to measure necrotic areas, which are assumed to be a sign of response to chemotherapy. Moreover, uterine zonal anatomy and subserosal uterine veins yielded important information on tumour biology. Complete remission was induced in high-risk patients by etoposide, methotrexate, and actinomycin D treatment.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Magnetic Resonance Imaging , Trophoblastic Neoplasms/drug therapy , Uterine Neoplasms/drug therapy , Adult , Dactinomycin/administration & dosage , Etoposide/administration & dosage , Female , Follow-Up Studies , Humans , Leucovorin/administration & dosage , Methotrexate/administration & dosage , Pregnancy , Trophoblastic Neoplasms/diagnosis , Uterine Neoplasms/diagnosis , Uterus/pathologyABSTRACT
Induratio penis plastica (Peyronie's disease) is a chronic fibrotic process involving the penis. Proper treatment of the disease requires assessment of the degree of inflammation preceding or accompanying the fibrous Peyronie's plaques. Owing to its high tissue contrast and its multiplanar capability, MR imaging offers excellent visualization of penile anatomy. To determine the usefulness of MR imaging in the diagnosis and staging of Peyronie's disease, we used MR imaging with a surface coil to examine 28 consecutive patients with clinical evidence of the disease. Eighteen patients had contrast-enhanced MR imaging with gadopentetate dimeglumine. In seven patients who subsequently had surgery or biopsy, MR findings were correlated with histopathologic findings. On unenhanced images, fibrous plaques were shown in 20 patients. Enhanced MR images showed focal contrast enhancement around or within the plaques in seven patients. Images in three patients with plaques showed no enhancement. Images in five patients showed focal areas of contrast enhancement without evidence of plaques. Histologic studies demonstrated that the degree of contrast enhancement correlated with the extent of inflammatory cell infiltration. In two patients with unenhancing plaques on MR, histology confirmed the absence of inflammation. Our results suggest that MR imaging not only depicts the localization and extent of fibrous plaques in patients with Peyronie's disease but also reveals the presence of inflammation. This makes MR imaging the technique of choice for planning therapy and for evaluating the response to conservative treatment.
Subject(s)
Magnetic Resonance Imaging , Penile Induration/diagnosis , Adult , Aged , Humans , Male , Middle Aged , Penis/pathologyABSTRACT
13 patients between 19 and 35 years, 12 of them with histologically verified trophoblastic disease, were examined by MRI, to prove the diagnostic value of this method. In line with the excellent results of MRI described in the literature with respect to the differentiation of tissue characterisation, vascularisation and localisation of tumours, the response to chemotherapy was evaluated comparatively to HCG-titres (5 patients). The results showed, that a decrease of HCG-titres correlated with significant tumour reduction. MRI was performed with 1.5 Tesla machines. Axial, sagittal and coronal images of pelvis and abdomen in T1, proton density and T1 sequences, one after administration of Gd-DTPA, were carried out. Except for one case with decreasing titres, GTP was proven by MRI. The tumour showed a remarkable lack of homogeneity and signal increase in 7 cases in T2-weighted images. In one case, the tumour showed a marked signal enhancement after applying Gd-DTPA, compared with the normal myometrium. In 5 cases, destruction of the zonal anatomy of the uterus and dilatation of subserosal uterine and pelvis veins were found. The uterus was larger in size than expected for the duration of gravidity. In correlation with the clinical examination and HCG titres, MRI has the potential of multiplanar imaging and signal characterisation of tissue, and is therefore useful to evaluate the tumour extent and to detect residuals. Gradient echo-technique and the use of contrast media will reduce the duration of examination, but more experience is required.
Subject(s)
Magnetic Resonance Imaging , Trophoblastic Neoplasms/diagnosis , Uterine Neoplasms/diagnosis , Adult , Choriocarcinoma/diagnosis , Choriocarcinoma/pathology , Chorionic Gonadotropin/blood , Contrast Media , Female , Gadolinium DTPA , Humans , Hydatidiform Mole/diagnosis , Hydatidiform Mole/pathology , Neoplasm Invasiveness , Neoplasm Staging , Neoplastic Cells, Circulating , Organometallic Compounds , Pentetic Acid , Pregnancy , Trophoblastic Neoplasms/pathology , Uterine Neoplasms/pathology , Uterus/pathologyABSTRACT
The effects of a single series of high-force eccentric contractions involving the quadriceps muscle group (single leg) on plasma concentrations of muscle proteins were examined as a function of time, in the context of measurements of torque production and magnetic resonance imaging (MRI) of the involved muscle groups. Plasma concentrations of slow-twitch skeletal (cardiac beta-type) myosin heavy chain (MHC) fragments, myoglobin, creatine kinase (CK), and cardiac troponin T were measured in blood samples of six healthy male volunteers before and 2 h after 70 eccentric contractions of the quadriceps femoris muscle. Screenings were conducted 1, 2, 3, 6, 9, and 13 days later. To visualize muscle injury, MRI of the loaded and unloaded thighs was performed 3, 6, and 9 days after the eccentric exercise bout. Force generation of the knee extensors was monitored on a dynamometer (Cybex II+) parallel to blood sampling. Exercise resulted in a biphasic myoglobin release profile, delayed CK and MHC peaks. Increased MHC fragment concentrations of slow skeletal muscle myosin occurred in late samples of all participants, which indicated a degradation of slow skeletal muscle myosin. Because cardiac troponin T was within the normal range in all samples, which excluded a protein release from the heart (cardiac beta-type MHC), this finding provides evidence for an injury of slow-twitch skeletal muscle fibers in response to eccentric contractions. Muscle action revealed delayed reversible increases in MRI signal intensities on T2-weighted images of the loaded vastus intermedius and deep parts of the vastus lateralis. We attributed MRI signal changes due to edema in part to slow skeletal muscle fiber injury.(ABSTRACT TRUNCATED AT 250 WORDS)
Subject(s)
Exercise/physiology , Muscles/injuries , Myosins/blood , Adult , Creatine Kinase/blood , Edema/etiology , Humans , Magnetic Resonance Imaging , Male , Muscle Contraction/physiology , Muscles/pathology , Muscles/physiopathology , Myoglobin/bloodABSTRACT
In a follow-up study of 20 patients with a total of 52 aortocoronary venous bypass grafts (ACVB) three months after surgery, the patency of the grafts was assessed by magnetic resonance tomography (MR) followed by contrast enhanced CT-scan and selective coronary angiography on the following day. Each examination was interpreted independently and immediately after the procedure for the visibility and patency of the grafts. The statistical figures for the non-occluded grafts showed a sensitivity of 90.24% and a specificity of 54.54% for the CT scans and a sensitivity of 73.17% with a specificity of 72.72% for the MR. Although the sensitivity of the CT is somewhat higher than that of MR, neither procedure offers a clear advantage over each other and neither of both methods alone is adequate for the assessment of ACVB's. They are therefore only valuable as an adjunct to clinical data and as a screening procedure for selective coronary angiography.