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At least 793 records · Page 44Linked to original sources
PubMed2005

Sentinel lymph node mapping of the pleural space.

STUDY OBJECTIVES: Although the sentinel lymph node (SLN) concept has traditionally been applied to solid organs, we hypothesized that the pleural space might drain into a specific SLN group. The identification of such a nodal group could assist in the staging and treatment of pleural-based diseases, such as mesothelioma, or other lung cancers with visceral pleural invasion. The purpose of this study was to determine whether the pleural space has an SLN group. DESIGN: Sixteen rats underwent right or left pleural space injection of a novel lymph tracer, quantum dots (QDs), which have a hydrodynamic diameter of 15 nm and fluoresce in the near-infrared (NIR) spectrum. Nodal uptake of the entire thorax was imaged with a custom system that simultaneously acquired color video, NIR fluorescence of the QDs, and a merged picture of the two in real-time. Six pigs underwent right or left pleural space injection of QDs and similar imaging. MEASUREMENTS AND RESULTS: In the rat, the QDs drained solely to the highest superior mediastinal lymph node group, corresponding to lymph node station 1, according the regional lymph node classification for lung of the American Joint Committee on Cancer. In one rat, the injection of QDs in the left pleural space resulted in migration to the contralateral station 1 lymph node group. The injection of QDs in the right or left pleural space of the pig resulted in migration solely to the ipsilateral highest superior mediastinal lymph node group. CONCLUSIONS: NIR fluorescence imaging in two species demonstrated that the highest superior mediastinal lymph nodes of station 1 are the SLNs of the pleural space. This study also provides intraoperative feasibility and proof of the concept for identifying lymph nodes communicating with the pleural space on a patient-specific basis, in real-time, and with high sensitivity.

Animals↗
PubMed1990

[Clinical study on the correlation between occlusion raising and free-way space].

This paper presents three cases in which CSC telescope dentures were inserted following occlusion raising. Post-operative course remained uneventful in all three cases. Follow-up observations suggested that the use of CSC telescope denture, is helpful in prosthetic treatment which includes occlusion raising. In Case 1, occlusion was raised to a level above the free-way space. However, a new free-way space appeared after occlusion raising and it existed for a long time. A free-way space, which conformed to a space calculated from the free-way space before occlusion raising and the amount of occlusion raising, appeared in Case 2. In Case 3, however, the free-way space after occlusion raising was narrower compared to a space calculated from free-way space before occlusion raising and amount of occlusion raising.

Dental Occlusion↗
PubMed2000

Effects of eating space and availability of water in feeders on productivity and eating behavior of grower/finisher pigs.

Three experiments were conducted to determine the effects of eating space and availability of water within feeders on the productivity and behavior of growing/finishing pigs. In Exp. 1, 12 commercial feeders were classified as being either single-space (SS) or multiple-space (MS), and either as dry (D) or wet/dry (WD), resulting in two SS-D, four MS-D, three SS-WD and three MS-WD models. Each model was evaluated using four pens of 12 pigs, which were fed a mash diet throughout the growing/finishing period (25 to 106 kg). Pigs were videotaped when they were approximately 40 and 80 kg in weight to determine eating behavior. The number of feeding spaces did not affect the productivity of the pigs, but the presence of water within the feeder resulted in increases in ADFI (P < .05) and ADG (P < .05) and a reduction in carcass lean (P < .05). Pigs eating from SS feeders spent 15% less time eating than those fed from two-space feeders (P < .05), and occupancy rate for feeding spaces was increased by 75% (P < .05). The WD feeders also resulted in a reduction (17%) in eatingtime compared to D models (P < .01), and occupancy rate for WD feeders was similarly reduced (P < .05). Pigs spent 16% less time eating when they weighed approximately 80 kg than when they weighed 40 kg (P < .01). In Exp. 2, rate of eating was determined during a short test on the same 12 feeder models for both small (48 kg) and large (90 kg) pigs. Large pigs ate faster than small pigs, but eating rate was not affected by feeding space or presence of water in the feeder. In Exp. 3, eating rate was determined for small amounts of dry or wet feed. Premixing water with the feed (1:1 ratio by weight) increased eating speed (P < .01). We concluded that 12 pigs can be fed from a single-space feeder without affecting productivity. The inclusion of water within a feeder decreases time spent eating, but it increases ADFI and ADG. When pigs are small, they spend more time eating, and feeder occupancy rates are higher than when they are large.

Animal Husbandry↗
PubMed2000

Group size and floor-space allowance can affect weanling-pig performance.

Crossbred weanling piglets (n = 1,920; mean initial BW, 5.3 +/- .7 kg) were used in two 9-wk trials employing a randomized block design in a 2 x 2 factorial arrangement of treatments to determine effects of group size (20 [Small = S] or 100 [Large = L] pigs/pen) and floor-space allowance (calculated requirement [CR] or calculated requirement less 50% of estimated "free space" [CR-50]) on growth performance. Free space was estimated for each group size. From wk 1 through 4 after weaning, S and L groups at CR were allowed a floor space of .17 m2/pig, and at CR-50, S and L groups were allowed .15 m2/pig and .13 m2/pig, respectively. From wk 5 through 9 after weaning, all CR treatment pigs were provided a floor space of .38 m2/pig, and for the CR-50 treatment, S and L pigs were allowed .32 m2/pig and .28 m2/pig, respectively. Piglets had free access to feed and water. Feeder-trough space per pig was the same for both group sizes. Feed-intake data were collected for only wk 1 through 4. Group size by floor-space allowance interactions (P < .05) were found for gain/feed ratio (G/F) for wk 1 and wk 2 through 4, but not for wk 1 through 4. Piglets in L groups were lighter (P < .001) at the end of wk 1, 4, and 9 by 2, 4, and 5%, respectively, and had lower ADG (6%; P < .001) throughout the trial than S piglets. During wk 1 through 4, feed intake was lower (7%, P < .001) in L piglets than in S piglets, but G/F was similar (P > .05). Piglets in CR groups had greater ADG (5%; P < .01) throughout the trial, with a greater G/F (P < .05) for wk 1 through 4, and were heavier (P < .01) than those in CR-50 groups at the end of wk 4 (3%) and 9 (4%). Pigs in L groups had a greater within-pen coefficient of variation in BW at the end of wk 9 than pigs in S groups. Large groups and reduced floor-space allowance reduced piglet growth performance in the nursery.

Animals↗
PubMed2002

Comparison of different infratentorial-supracerebellar approaches to the posterior and middle incisural space: a cadaveric study.

OBJECT: The purpose of this investigation was to describe and compare through cadaveric dissection the microsurgical exposure afforded by the median, paramedian, and extreme-lateral infratentorial-supracerebellar approaches to the posterior and middle incisural space. METHODS: The median, paramedian, and extreme-lateral infratentorial-supracerebellar approaches were performed in 10 embalmed cadaveric heads by using standard microneurosurgical methods; each approach was executed a minimum of five times. The dissections were performed in a stepwise fashion, comparing the exposure afforded by each surgical route and highlighting the relationships among the targeted neurovascular structures. Exposure of the dural sinuses and transection of the tentorium were also evaluated in relation to the degree of exposure achieved. The median infratentorial-supracerebellar route provides direct exposure of the posterior incisural space, although the culmen represents a relative obstacle to exposure of the lower quadrigeminal plate. The paramedian variant allows a more lateral perspective on the posterolateral brainstem surface at the level of the middle incisural space, in addition to exposing the homolateral collicular plate. The extreme-lateral corridor widens the exposure of the paramedian approach to include the anterolateral brainstem surface, offering a complete view of the cisternal space surrounding the middle incisural space. Complete, constant exposure and retraction of the dural sinuses facilitated the surgical exposure. CONCLUSIONS: The infratentorial-supracerebellar approaches allow safe circumferential exposure of the posterior and middle incisural space. Choosing among different variants allows the surgeon to reach selected areas, with the midline variant being best for exposure of the posterior incisural space, and the paramedian and extreme-lateral variants being best for reaching the posterior and the anterior part of the middle incisural space, respectively. The more lateral the approach, the more anterior and multiangled the exposure gained. Complete, constant exposure and retraction of the dural sinuses improves the exposure. Accurate knowledge of the regional anatomy is mandatory.

Cadaver↗
PubMed1994

Effects of floor versus cage rearing and feeder space on growth, long bone development, and duration of tonic immobility in single comb White Leghorn pullets.

The effects of feeder space on growth of commercial layer pullets reared in cages or floor pens were examined by allocating 1-d-old chicks to either cages (14 chicks) or floor (119 chicks). Feeder spaces were 5.4, 4.0, and 2.7 cm per pullet and were held constant throughout the growing period, resulting in a 2 x 3 factorial arrangement. Measurements of pullet body weight, feed consumption, skeletal development, and fearfulness were taken through the rearing period to 18 wk. Pullets allowed 5.4 cm of feeder space were heavier (P < .001) (1,329 g at 18 wk of age) than birds allowed either 4.0 or 2.7 cm of feeder space (1,289 and 1,272 g, respectively). Floor-reared pullets weighed significantly more at 12, 16, and 18 wk of age than cage-reared pullets. Feed consumption was not affected by the feeder space, but the floor-reared birds consumed more (P < .001) feed than those in cages (61.2 vs 52.8 g per pullet per d). Mortality, skeletal development, and bone strength were not affected by either feeder space or floor vs cage rearing. Floor-reared pullets had longer (P < .05) duration of tonic immobility (TI) than those reared in cages (519.7 and 471.4 s, respectively, as measured at 18 wk). Feeder space per pullet had no effect on the duration of TI of the pullets. Cage and floor rearing environments are comparable for rearing pullets provided feeder space is not restricted to such an extent as to inhibit BW.

Animal Husbandry↗
PubMed2000

Dental changes and space gained as a result of early treatment of pseudo-Class III malocclusion.

This study was designed to investigate the dental changes and the space gained following early treatment of pseudo-Class III malocclusion, using a simple fixed appliance. Twenty-one consecutively treated patients who had a pseudo-Class III malocclusion comprised the treated group. Fifteen untreated control subjects were used as matched controls for the three-year follow-up after completion of treatment. Lateral cephalograms and study models were analysed for the treated, the control and the follow-up group. The arithmetic mean and standard deviation were calculated for each variable, and paired t-tests were performed to assess the effects of treatment on the treated group. The Mann-Whitney test was performed to evaluate the difference between the follow-up group and the control group. Anterior crossbites and mandibular displacements were eliminated after the treatment. On average, the space gained as a result of the treatment was 4.7 mm in the upper arch (p < 0.001 degree). Comparison of the space available as a result of early treatment with the space required for alignment of posterior segments in the upper arch of the untreated control group indicated that there was enough space for the eruption of the canines and premolars as a result of early treatment; whereas, lack of space was evident in the untreated controls. In conclusion, a pseudo-Class III malocclusion, proclination of the upper incisors and/or retroclination of the lower incisors contributed to the correction of anterior crossbite and the elimination of mandibular displacement. Proclination of the upper incisors, utilisation of leeway space, and arch-width increase provided the space required for eruption of the premolars and canines.

Bicuspid↗
PubMed2001

Floor space needs for laboratory mice: BALB/cJ males or females in solid-bottom cages with bedding.

Studies were initiated to determine the effects of restricted (32.2 cm2 per mouse), normal (96.8 cm2), or excess floor space (129.0 cm2) allowances by using a model of three mice per cage. BALB/cJ mice were bred on-site and weaned at 3 weeks of age into specially designed polycarbonate shoebox cages modified to each space allowance. Cages contained aspen shavings for bedding, and mice were fed and watered ad libitum. Body weight gains, feed and water use, and immunologic measures largely were not effected by floor space allowances. Female BALB/cJ mice were heavier and had increased lymphocyte blastogenesis to phytohemagglutinin (20 microg/mL) when given 32.2 cm2/mouse than when given 129 cm2/mouse. Female mice showed an increase in grooming and sitting behaviors when given 32.2 cm2/mouse, but male mice with restricted floor space spent more time lying down but showed no change in grooming or sitting behaviors compared to mice given more space. Among male mice, limited floor space did not significantly influence growth rates, but male mice given 32.2 cm2/mouse had less mortality than did mice given more space. We conclude that floor spaces as limited as 32.2 cm2/mouse did not cause behavior, health, immune or performance problems for BALB/cJ mice.

Animals↗
PubMed2001

Reliability and sensitivity of joint space measurements in hand radiographs using computerized image analysis.

OBJECTIVE: To establish the sensitivity and reliability of proximal interphalangeal (PIP) and metacarpophalangeal (MCP) mean joint space measurements using standard clinical radiographs of healthy subjects, in order to determine the limits at which a change in radiographic joint space could indicate a change in actual joint size. METHODS: Repeat hand radiographs of healthy subjects were taken using standard techniques at 3-5 day intervals with the hands flat (5 posteroanterior radiographs in 8 subjects) or in 6 different flexed positions on a single occasion (8 subjects). The mean joint space was determined using custom soft ware and was validated manually. Measurement reproducibility within subjects, within films, and between hand positions was assessed by analysis of variance. RESULTS: In repeat radiographs taken in the standard clinical position, the precision of individual join space measurements indicates that changes > 0.11 mm (approximately 7%) would represent an actual physical change in joint space width (with 95% probability). Averaging measurements across fingers for a single subject decreases the detectable change to 0.05 mm (approximately 3%). With increasing flexure, radiographic joint space tended to increase in MCP and decrease in PIP. CONCLUSION: Mean finger joint space measured from standard clinical radiographs is a reliable and sensitive measurement in healthy subjects even with some change in hand position. Work is required to establish whether the joint space change measured from serial radiographs of patients with arthritis over a period of 6-12 mo exceeds the detectable limits of change derived in this study.

Adult↗
PubMed2000

Spaced dentition--open, close or redistribute?

A spaced dentition can be due to various reasons such as hypodontia, tooth size discrepancy and impeded eruption. The dilemma for clinicians is whether to close, open or redistribute space. Closing space by orthodontics eliminates the need for prosthetic rehabilitation but it might compromise aesthetics and function. On the other hand, opening space is more complex and requires long-term maintenance. Based on these drawbacks, a careful occlusal analysis and an individualized treatment plan are mandatory for achieving the best result. The prognosis for closing space and substituting congenitally missing maxillary laterals with canines depends on factors such as overjet, lip support, crown colour, shape and root position. If these are unfavourable, opening space for prosthetic replacement is then preferred. Discrepancy between tooth and jaw size results either in spacing or crowding. The location of the spacing and the amount of overjet are important factors guiding the direction of treatment.

Adolescent↗
PubMed2001

Development of a space radiation Monte Carlo computer simulation based on the FLUKA and ROOT codes.

This NASA funded project is proceeding to develop a Monte Carlo-based computer simulation of the radiation environment in space. With actual funding only initially in place at the end of May 2000, the study is still in the early stage of development. The general tasks have been identified and personnel have been selected. The code to be assembled will be based upon two major existing software packages. The radiation transport simulation will be accomplished by updating the FLUKA Monte Carlo program, and the user interface will employ the ROOT software being developed at CERN. The end-product will be a Monte Carlo-based code which will complement the existing analytic codes such as BRYNTRN/HZETRN presently used by NASA to evaluate the effects of radiation shielding in space. The planned code will possess the ability to evaluate the radiation environment for spacecraft and habitats in Earth orbit, in interplanetary space, on the lunar surface, or on a planetary surface such as Mars. Furthermore, it will be useful in the design and analysis of experiments such as ACCESS (Advanced Cosmic-ray Composition Experiment for Space Station), which is an Office of Space Science payload currently under evaluation for deployment on the International Space Station (ISS). FLUKA will be significantly improved and tailored for use in simulating space radiation in four ways. First, the additional physics not presently within the code that is necessary to simulate the problems of interest, namely the heavy ion inelastic processes, will be incorporated. Second, the internal geometry package will be replaced with one that will substantially increase the calculation speed as well as simplify the data input task. Third, default incident flux packages that include all of the different space radiation sources of interest will be included. Finally, the user interface and internal data structure will be melded together with ROOT, the object-oriented data analysis infrastructure system. Beyond the benefits of 'objectivity', ROOT's incorporation will also provide a graphical user interface with powerful tools for input prior to the calculation, as well as for data analysis and visualization of the results.

Computer Simulation↗
PubMed2002

Management of complex multi-space odontogenic infections.

The successful management of multi-space orofacial odontogenic infections involves identification of the source of the infection, the anatomical spaces encountered, the predominant microorganisms that are found during the various stages of odontogenic fascial space infection, the impact of the infectious process on defense systems, the ability to use and interpret laboratory data and imaging studies, and a thorough understanding of contemporary antibiotic and supportive care. The therapeutic goals, when managing multi-space odontogenic infections, are to restore form and/or function while limiting patient disability and preventing recurrence. Odontogenic infections are commonly the result of pericoronitis, carious teeth with pulpal exposure, periodontitis, or complications of dental procedures. The second and third molars are frequently the etiology of these multi-space odontogenic infections. Of the two teeth, the third molar is the more frequent source of infection. Diagnostic imaging modalities are selected based on the patient's history, clinical presentation, physical findings and laboratory results. Periapical and panoramic x-rays are reliable initial screening instruments used in determining etiology. Magnetic resonance imaging and computed tomography are ideal imaging studies that permit assessment of the soft tissue involvement to include determining fluid collections, distinguishing abscess from cellulitis, and offering insight as to airway patency. Antibiotics are administered to assist the host immune system's effort to control and eliminate invading microorganisms. Early infections, first three (3) days of symptoms, are primarily caused by aerobic streptococci which are sensitive to penicillin. Amoxicillin is classified as an extended spectrum penicillin. The addition of clavulanic acid to amoxicillin (Augmentin) increases the spectrum to staphylococcus and other anaerobes by conferring beta-lactamase resistance. In late infections, more than three (3) days of symptoms, the predominant microorganisms are anaerobes, predominantly Peptostreptococcus, Fusobacterium, or Bacteroides, that are resistant to penicillin. Clindamycin is an attractive alternative drug for first line therapy in the treatment of these infections. The addition of metronidazole to penicillin is also an excellent treatment choice. Alternatively, Unasyn (Ampicillin/Sublactam), should be considered. The mainstay of management of these infections remains appropriate culture for bacterial identification, timely and aggressive incision and drainage, and removal of the etiology. It is usually preferable to drain multi-space infections involving the submandibular, submental, masseteric, pterygomandibular, temporal, and/or lateral pharyngeal masticator spaces, as early as possible from an extraoral approach. Trismus and airway management are important considerations and may preclude the selection of other surgical approaches. The patients with multi-space infections should be hospitalized and patient care provided by experienced clinicians capable of management of airway problems, in administration of parenteral antibiotics and fluids, utilization of interpretation of laboratory and diagnostic imaging studies, and control of possible surgical complications.

Abscess↗
PubMedDate not supplied

[The fragmentation of representational space in schizophrenia].

Existent neurocognitive models of schizophrenia converge towards a core of impairments involving working memory, context processing, action planning, controlled and intentional processing. However, the emergence of this core remains itself difficult to explain and more specific hypotheses do not explain the heterogeneity of schizophrenia. To overcome these limits, we propose a new paradigm based on representational theory from cognitive science. Some recent developments of this theory enable us to describe a subjective universe as a representational space which is displayed from memory. We outline a conceptual framework to construct such a representational space from analogical -representations that can be activated in working memory and are connected to a network of symbolic structures. These connections are notably made through an analytic process of the analogical fragments, which involves the attentional focus. This framework allows us to define rigorously some defense processes in response to traumatic tensions that are expressed on the representational space. The fragmentation of representational space is a consequence of a defensive denial based on an impairment of the analytic process. The fragmentation forms some parasitic areas in memory which are excluded from the main part of the representational space and disturb information processing. The key clinical concepts of paranoid syndromes can be defined in this conceptual framework: mental automatism, delusional intuition, acute destructuration, psychotic dissociation, and autistic withdrawal. We show that these syndromes imply each other, which in return increases the fragmentation of the representational space. Some new concepts emerge naturally in this framework, such as the concept of "suture" which is defined as a link between a parasitic area and the main representational space. Schizophrenia appears as a borderline case of fragmentation of the representational space. This conceptual framework is compatible with numerous etiological factors. Multiple clinical forms can be differentiated in accordance with the persistence of parasitic areas, the degree of fragmentation, and the formation of sutures. We use this approach to account for an empirical study concerning the analysis of analogical representations in schizophrenia. We used the Parallel Visual Information Processing Test (PVIPT) which assesses the analysis of interfering visual information. Subjects were asked to connect several small geometric figures printed on a transparency. The transparency was displayed above four photographs which were the interfering material. Then, subjects completed three tasks concerning the photographs: a recognition task, a recall task, and an affective qualification task. Using a case-by-case study, this test allows us to access the defense processes of the subjects, which is not possible with the usual methods in cognitive psychopathology. Twelve clinically-stable schizophrenic subjects participated in the study which also included a self-assessment of alexithymia by the Toronto Alexithymia Scale. We obtained 2 main results: (a) creation of items in recall or false recognition by 8 subjects, and (b) lack of the usual -negative correlations between the alexithymia score and the recall, recognition and affective qualification scores in the PVIPT. These 2 results contrast with what has been previously observed for alexithymia using the same methodology. The result (a) confirms an interfering activation in schizophrenic memory, which can be interpreted in our framework as indicative of parasitic areas. The creation of items suggests the formation of sutures between the semantic content of photographs and some delusional fragments. The result (b) suggests that the apparent alexithymia in schizophrenia is a defense against interfering activation in parasitic areas. We underline the interest of individual protocols to exhibit the dynamic interplay between an interfering activity in memory and a defensive flattening of affects.

Affective Symptoms↗
PubMed2004

[A case of poorly differentiated lung adenocarcinoma showing air-space consolidation caused by aerogenic metastasis].

A 78-year-old woman was admitted to our hospital because of dyspnea. A chest radiograph and a computed tomogram on admission showed air-space consolidation in the left upper lung field, and so pneumonia was diagnosed. Although antibiotics were administered, the air-space consolidation did not improve. A transbronchial lung biopsy was performed, yielding a pathologic diagnosis of poorly differentiated lung adenocarcinoma. Despite combination chemotherapy with docetaxel and UFT, the air-space consolidation expanded, and the patient finally died of respiratory failure 3 months after diagnosis. Autopsy revealed air-space consolidation due to poorly differentiated lung adenocarcinoma, with large atypical cells diffusely floating in the alveolar spaces. It has been recognized that bronchiolo-alveolar carcinoma and well-differentiated lung adenocarcinoma present with air-space consolidation, reflecting the cancer cells lining the alveolar walls. However, in this case, the air-space consolidation was due to cancer cells diffusely floating in the alveolar spaces in aerogenic metastasis. It was considered that this is a rare case, which presented with a very interesting development pattern.

Adenocarcinoma↗
PubMed2004

Finding the right approach. What do you mean, this is a non-permit required confined space?

While not a big fan of the non-permit confined space designation, I have come to believe the approach can work if done properly. However, it is this author's opinion that the designation of a confined space as non-permit required in any work environment should be the exception rather than the rule. The up-front determination that a space is "non-permit-required" should necessarily consume more time and resources than assuming the space is "permit-required" because so fewer controls are in place. Most certainly, this decision must be based on the knowledge that no hazards are present or have the potential to develop, rather than on "convenience" or "resource limitations"; assumptions should never play a part in the decision. Attention to proper evaluation of confined spaces, documentation of actual conditions over time, and communication to those entering the spaces are all critical components of a safe confined space entry program, whether the space be permit-required or not.

Guideline Adherence↗
PubMed2005

MR imaging of normal perivascular space expansion at midbrain.

BACKGROUND AND PURPOSE: A previous investigation of the MR imaging findings in the midbrain reported expanded perivascular (PV) spaces in only the ponto-mesencepalic junction (PMJ) in 20% of healthy subjects, whereas pathologically expanding PV spaces have been reported at the mesencephalo-diencephalic junction (MDJ) as multi-lobulated, cystic lesions with signal intensity compatible with that of CSF that cause aqueductal stenosis. To clarify the anatomical distinctions between normally expanded and pathologically expanding PV spaces, we defined their distribution in the normal midbrain by using high-spatial-resolution MR imaging. METHODS: Heavily T2-weighted MR imaging was performed in 115 adult subjects with neurologic complaints without cerebral disease. Histologic studies were performed from two normal midbrain blocks. RESULTS: Expanded PV spaces were visible at the PMJ in 87% of subjects and at the MDJ in 63% of subjects. On axial images, ovoid or linear lesions with signal intensity compatible to CSF were present behind the cerebral peduncle at both the PMJ and MDJ. These areas varied from less than 1 mm to 5 mm (maximum diameter on coronal sections). Histologic studies confirmed the distribution of expanded PV spaces, as noted on MR images. CONCLUSION: This study, by using high-spatial-resolution MR imaging, revealed that expanded PV spaces were visible at the PMJ and MDJ. Our finding of expanded PV spaces normally present at the MDJ may be related to pathologically expanding PV spaces, which should be kept in mind as a differential diagnosis for intraparenchymal cystic lesions in the midbrain with signal intensity compatible to CSF.

Adolescent↗
PubMed2005

[CT and MRI features of diseases involving masticator spaces].

OBJECTIVE: This is a study on the CT and MRI features of diseases involving the masticator spaces; the purpose is to improve the diagnostic accuracy. METHODS: Fifty-seven cases involving the masticator spaces were collected, among which, 11 cases were originated from the masticator space, another 46 cases were secondary invasion from the adjacent structures, including 18 cases from the buccal mucosa, 10 from the nasopharynx, 5 from the gingiva, 3 from the parotid gland, 6 from the maxillary sinus, 1 from the intracranial location, 2 from the palate and 1 from the orbit. The CT and MRI features of the masticator space involvement were analysed. RESULTS: Masticator space involvement is visualized on CT and MRI as effacement of the fat plane, swelling of the masticatory muscles, and erosion of the mandibular ramus. Disease from surrounding structures can invade the masticator space via the pterygopalatine fossa, the buccal space immediately anterior to the ramus, the foramen ovale, or by way of direct invasion. CONCLUSION: Masticator space involvement is not uncommon in the maxillofacial diseases, which must be noticed in the imaging diagnosis.

Adolescent↗
PubMed1992

Partial purification, from Xenopus laevis oocytes, of an ATP-dependent activity required for nucleosome spacing in vitro.

A critical feature of chromatin with regard to structure and function is the regular spacing of nucleosomes. In vivo, spacing of nucleosomes occurs in at least two steps, but the mechanism is not understood. In this report, we have mimicked the two-step process in vitro. A novel spacing activity has been partially purified from Xenopus laevis ovaries. When this activity is added, either at the beginning or at the end of a nucleosomal assembly reaction, it can convert a DNA template consisting of irregularly spaced nucleosomes into a chromatin structure made up of regularly spaced nucleosomes with a repeat length of about 165 base pairs. The reaction requires ATP. Histone H1 is able to increase the nucleosomal repeat from 165 to 190 base pairs. This two-step increase in nucleosomal repeat length suggests that both the spacing activity and histone H1 contribute to generating repeat lengths of greater than 165 base pairs and that their contributions may be additive. Alternatively, the critical step in the spacing reaction may not be the formation of the 165-base pair repeat but may be the sliding of nucleosomes or the reorganization of the octamer structure induced by the spacing activity.

Adenosine Triphosphate↗