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At least 649 records · Page 36Linked to original sources
PubMed2001

Hepatocellular carcinoma treated with radiofrequency ablation: comparison of pulse inversion contrast-enhanced harmonic sonography, contrast-enhanced power Doppler sonography, and helical CT.

OBJECTIVE: The purpose of this study was to compare the efficacy of contrast-enhanced pulse inversion harmonic imaging with contrast-enhanced power Doppler sonography and helical CT to determine incomplete local treatment after radiofrequency ablation in patients with hepatocellular carcinoma. MATERIALS AND METHODS: Thirty-five consecutive patients (24 men and 11 women; mean age, 64 years) with 43 hepatocellular carcinomas (3.6 +/- 1.1 cm) were treated using internally cooled radiofrequency ablation therapy. Therapeutic response was evaluated at 4 months with dual-phase contrast-enhanced helical CT, conventional power Doppler Sonography, and pulse inversion harmonic imaging using a sonographic contrast agent (SH-508). CT and sonographic studies were reviewed separately in random order by four radiologists at different consensus conferences. Sensitivity and specificity of the sonographic methods were determined using CT as a gold standard and results were compared using the McNemar test. RESULTS: CT examinations identified residual tumor in 12 lesions (27.9%). Although conventional contrast-enhanced power Doppler sonography identified residual viable tumor foci in four incompletely treated lesions (9.3%), contrast-enhanced pulse inversion harmonic imaging identified residual tumoral enhancement in 10 lesions (23.3%). Thus, the sensitivity of pulse inversion harmonic imaging (83.3%) was significantly greater (p < 0.05) for detecting residual nonablated tumor compared with conventional contrast-enhanced power Doppler sonography. CONCLUSION: Our study suggests that contrast-enhanced pulse inversion harmonic imaging may enable the detection of residual nonablated tumor in more cases than contrast-enhanced power Doppler sonography and may ultimately prove to be a useful adjunct for percutaneous ablation therapies. Nevertheless, contrast-enhanced axial imaging (CT or MR imaging) is currently the most sensitive test for managing thermal ablation for patients with hepatocellular carcinoma.

Carcinoma, Hepatocellular↗
PubMed2003

Deficits in detection of inversion and eversion movements among subjects with recurrent ankle sprains.

STUDY DESIGN: Observational cross-sectional design. OBJECTIVES: To determine whether a deficit exists in the ability to perceive inversion and eversion movements among subjects with recurrent ankle sprains. BACKGROUND: Although unproven, ankle sprains are thought to recur because proprioception is impaired subsequent to the original sprain. Proprioception has been widely studied, however, the specific property of movement perception has not been rigorously examined for both inversion and eversion movements. METHODS AND MEASURES: The ability to perceive passive inversion and eversion movements imposed at the relaxed ankle was measured in 39 subjects with recurrent ankle sprains (sprainers) and 30 subjects with no history of ankle injury (controls) by an assessor masked to subject group. The 70% detection level for movement perception was determined for 3 velocities, 0.1 degrees/s, 0.5 degrees/s, and 2.5 degrees/s, tested in random order. RESULTS: The 70% detection level for inversion and eversion movements improved with increasing velocity in both groups. At all velocities, the 70% detection level for movements imposed at the ankle of the sprainers was significantly worse than for controls. CONCLUSIONS: Perception of passive inversion and eversion movements imposed at the ankle was impaired in subjects with recurrent ankle sprains. The impairment was evident at the 3 velocities tested, 0.1 degrees/s, 0.5 degrees/s, and 2.5 degrees/s.

Adolescent↗
PubMed1991

Rapid inversion of additive by additive relationship matrices by including sire-dam combination effects.

Inverses of relationship matrices are useful for prediction of individual additive or nonadditive genetic merits and for estimation of variance components. An algorithm to form inverses of additive by additive relationship matrices rapidly from lists of individuals and their parents was developed. The algorithm uses simple recurrences among additive by additive and sire-dam combination effects to construct inverses for noninbred or inbred populations. Dimensions of matrices produced may be several times the number of individuals in the population because combination effects for sire-dam subclasses must be included in matrices. Rules of inheritance of sire-dam combination effects are the same as for dominance combination effects. Cost of forming inverses increases linearly with number of individuals. Each individual contributes 36 or fewer nonzero coefficients, and each sire-dam subclass contributes an additional 81 or fewer nonzero coefficients to the matrix. Computation of inverse of the relationship matrix due to 1003 sires and maternal grandsires of 765,868 cows required forming a matrix of order 137,830 and 4 Mbytes of memory.

Algorithms↗
PubMed2002

Determining the influence of Gaussian blurring on inversion effects with talking faces.

Perception of visual speech and the influence of visual speech on auditory speech perception is affected by the orientation of a talker's face, but the nature of the visual information underlying this effect has yet to be established. Here, we examine the contributions of visually coarse (configural) and fine (featural) facial movement information to inversion effects in the perception of visual and audiovisual speech. We describe two experiments in which we disrupted perception of fine facial detail by decreasing spatial frequency (blurring) and disrupted perception of coarse configural information by facial inversion. For normal, unblurred talking faces, facial inversion had no influence on visual speech identification or on the effects of congruent or incongruent visual speech movements on perception of auditory speech. However, for blurred faces, facial inversion reduced identification of unimodal visual speech and effects of visual speech on perception of congruent and incongruent auditory speech. These effects were more pronounced for words whose appearance may be defined by fine featural detail. Implications for the nature of inversion effects in visual and audiovisual speech are discussed.

Acoustic Stimulation↗
PubMed1997

Facial inversion effects: parts and whole relationship.

"Facial inversion effects" refers to the findings that recognition of inverted faces is less accurate than recognition of upright faces. We now report inversion effects for isolated facial features: forehead, eyes, nose, mouth, and chin. This shows that configurational information extracted from a whole face (i.e., from spatial relationships among the facial features) is not necessary for obtaining the inversion effects. Other factors, such as "upright-orientation," mental rotation, and feature saliency, account for the inversion effects both in a whole face and in its isolated features. We propose a simple formula that satisfactorily predicts the recognition of a whole face and the inversion effects for that face on the basis of its individual features.

Adult↗
PubMed1991

Second-order relational properties and the inversion effect: testing a theory of face perception.

Recognition of faces is more severely impaired by inversion than is recognition of other types of objects. This was originally interpreted as evidence for the existence of special face-recognition mechanisms. Recently, Diamond and Carey (1986) attributed the inversion effect to the use of second-order relational properties that are important for, but not unique to, face recognition. According to their hypothesis, face recognition differs from the recognition of most other objects in its dependence on second-order relational properties. This hypothesis was tested in two experiments by comparing the effects of inversion on the identification of dot patterns that differed in the extent to which they required the encoding of second-order relational properties. Identification of the second-order relational patterns was not more disrupted by inversion than was identification of first-order patterns. These results fail to support the hypothesis that second-order relational properties are responsible for the inversion effect.

Adult↗
PubMed2002

The effects of axial preload and dorsiflexion on the tolerance of the ankle/subtalar joint to dynamic inversion and eversion.

Forced inversion or eversion of the foot is considered a common mechanism of ankle injury in vehicle crashes. The objective of this study was to model empirically the injury tolerance of the human ankle/subtalar joint to dynamic inversion and eversion under three different loading conditions: neutral flexion with no axial preload, neutral flexion with 2 kN axial preload, and 30 degrees of dorsiflexion with 2 kN axial preload. 44 tests were conducted on cadaveric lower limbs, with injury occurring in 30 specimens. Common injuries included malleolar fractures, osteochondral fractures of the talus, fractures of the lateral process of the talus, and collateral ligament tears, depending on the loading configuration. The time of injury was determined either by the peak ankle moment or by a sudden drop in ankle moment that was accompanied by a burst of acoustic emission. Characteristic moment-angle curves to injury were generated for each loading configuration. Neutrally flexed ankles with no applied axial preload sustained injury at 21 +/- 5 Nm and 38 degrees +/- 8 degrees in inversion, and 47 +/- 21 Nm and 28 degrees +/- 4 degrees in eversion. For ankles tested in neutral flexion with 2 kN of axial preload, inversion failure occurred at 77 +/- 27 Nm and 40 degrees +/- 12 degrees , and eversion failure occurred at 142 +/- 100 Nm and 41 degrees +/- 14 degrees . Ankles dorsiflexed 30 degrees and axially preloaded to 2 kN sustained inversion injury at 62 +/- 31 Nm and 33 degrees +/- 4 degrees , and eversion injury at 140 +/- 53 Nm and 40 degrees +/- 6 degrees . Survival analyses were performed to generate injury risk curves in terms of joint moment and rotation angle.

Journal Article↗
PubMed2001

Detection of parenchymal abnormalities in acute pyelonephritis by pulse inversion harmonic imaging with or without microbubble ultrasonographic contrast agent: correlation with computed tomography.

The purpose of this study was to evaluate the ability of pulse inversion harmonic imaging with or without microbubble ultrasonographic contrast agent in depicting renal parenchymal changes in acute pyelonephritis. The study population included 30 patients with acute pyelonephritis and 10 healthy volunteers. Pulse inversion harmonic imaging with or without contrast agent was compared with conventional ultrasonography and tissue harmonic imaging in terms of detection and conspicuity of renal abnormalities. The detection and conspicuity of renal parenchymal abnormalities in acute pyelonephritis on tissue harmonic imaging, pulse inversion harmonic imaging, and contrast-enhanced pulse inversion harmonic imaging were significantly better than those on conventional ultrasonography. In 2 of 10 healthy volunteers all 4 techniques yielded false-positive diagnoses of parenchymal abnormalities. In conclusion, tissue harmonic imaging and pulse inversion harmonic imaging are sensitive techniques for depicting renal parenchymal lesions in acute pyelonephritis. Despite relatively lower specificities and negative predictive values, these techniques are thought to be useful for the depiction of subtle parenchymal changes in acute pyelonephritis.

Acute Disease↗
PubMedDate not supplied

[Regulation of catalytic properties of enzymes in "inverse micelles"].

A triple system (inverse micellae) that simulates the membrane environment of the enzyme was studied. Inverse micellae were obtained using anionic (aerosol OT), synthetic (Brij 56), and natural (lecithin) surfactants. It was found that upon inclusion of an enzyme into inverse micellae, its activity can be regulated by changing the structure and nature of the surfactant matrix. It was shown that enzyme activity in micellar environment is much higher than in water solution. Moreover, the enzyme solubilized in inverse micellae (acid phosphatase) shows a superactivity. It was found that surfactants specifically interact with solubilized enzyme, and the activity of the enzyme is inversely proportional to surfactant concentration. The mechanisms of viscotropic regulation of enzyme activity are discussed.

Acid Phosphatase↗
PubMed2000

Ultrasonographic evaluation of focal hepatic lesions: comparison of pulse inversion harmonic, tissue harmonic, and conventional imaging techniques.

A prospective study was performed to evaluate whether pulse inversion harmonic imaging and tissue harmonic imaging improve the lesion conspicuity and change ultrasonographic characteristics of focal hepatic lesions. Three radiologists evaluated 97 focal hepatic lesions by consensus: cirrhosis-related nodules (n = 23), metastases (n = 23), hemangiomas (n = 27), and cysts (n = 24). In our study, pulse inversion harmonic imaging was judged superior to both tissue harmonic imaging and conventional imaging in conspicuity and overall quality for cirrhosis-related nodules, metastases, and cysts (P < 0.05). Compared with conventional imaging, both pulse inversion harmonic imaging and tissue harmonic imaging provided better conspicuity, clearer internal echogenicity, and stronger through-transmission of cysts (P < 0.05). Pulse inversion harmonic imaging was judged to be better in depicting internal morphology for cirrhosis-related nodules and metastases than conventional imaging (P < 0.05). For hemangiomas, no statistically significant difference was found in all parameters except better posterior enhancement by tissue harmonic imaging than other techniques. In conclusion, pulse inversion harmonic imaging showed the best conspicuity and also enhanced characteristics of both cystic and solid hepatic lesions. Tissue harmonic imaging was judged superior to conventional imaging in evaluating cysts but was not beneficial for solid lesions. The results of this trial may be specific to the machine used for this study.

Adult↗
PubMed2001

Reduction of CSF and blood flow artifacts on FLAIR images of the brain with k-space reordered by inversion time at each slice position (KRISP).

BACKGROUND AND PURPOSE: Our purpose was to test a new variant of the fluid-attenuated inversion-recovery (FLAIR) sequence that was designed to reduce CSF and blood flow artifacts by use of a non-slice-selective inversion pulse and k-space reordered by inversion time at each slice position (KRISP). METHODS: With the KRISP FLAIR sequence, the slice order was cycled so that each inversion time (TI) was associated with a region of k-space rather than a particular slice, and the effective inversion time (TI(eff)) was chosen to null the signal from CSF. Scans were obtained with both conventional and KRISP FLAIR sequences. Studies were performed in 20 adult patients with a variety of brain diseases. Images were evaluated for artifacts from patient motion, CSF, and blood flow, and scored on a four-point scale. The conspicuity of the cortex, meninges, ventricular system, brain stem, and cerebellum was evaluated, as was lesion number and conspicuity. RESULTS: The KRISP FLAIR sequence showed more patient motion artifacts but had a pronounced advantage over the conventional sequence in control of CSF artifacts around the foramen of Munro, in the third ventricle, aqueduct, and fourth ventricle, as well as in the basal cisterns and around the brain stem and cerebellum. Blood flow artifacts from the internal carotid, basilar, and vertebral arteries were also much better controlled. Spurious high signal in the sylvian branches of the middle cerebral artery was eliminated. The meninges, cortex, ventricular system, brain stem, and cerebellum were better seen due to improved artifact suppression and an edge enhancement effect. CONCLUSION: The KRISP FLAIR sequence can suppress CSF and blood flow artifacts and improve the conspicuity of the meninges, cortex, brain stem, and cerebellum. Its major disadvantage is its duration, which may be reducible with a fast spin-echo version.

Adolescent↗
PubMedDate not supplied

Contrast-enhanced, wide-band phase-inversion power Doppler imaging of hepatic focal nodular hyperplasia.

BACKGROUND/AIMS: To determine whether examination of hepatic focal nodular hyperplasia by wide-band, phase-inversion sonography offers any advantages over power and color Doppler sonography in the depiction of specific characteristics of these pathologies. METHODOLOGY: Twenty-six patients were examined. The presence of focal nodular hyperplasia was confirmed by ultrasound-guided biopsy, surgical resection, dynamic helical computed tomography or magnetic resonance. All patients, prior to enhanced sonography, had undergone B-mode gray-scale sonography, color Doppler, and power Doppler examinations. After injection of 2.5 g of Levovist intravenously, analysis of the contrast agent arrival was performed by wide-band, phase-inversion power Doppler sonography. RESULTS: The B-mode gray-scale sonography, color and power Doppler sonography were non-specific for focal nodular hyperplasia in 14 cases in our examination. However based on the wide-band, phase-inversion power Doppler sonography findings all patients with focal nodular hyperplasia were diagnosed. All typical anatomic features of focal nodular hyperplasia such as "star sign" or "spoke-wheel" pattern were clearly visible. In 3 cases, computed tomography and magnetic resonance imaging had failed to disclose pathology while phase-inversion sonographic images were completely suggestive which was later finally confirmed by histologic examination. CONCLUSIONS: Our data demonstrate the usefulness of wide-band, phase-inversion power Doppler sonography in the differential diagnosis of hepatic focal nodular hyperplasia by visualizing all characteristic anatomic details.

Adult↗
PubMed2005

Practical aspects of inverse-planned intensity-modulated radiation therapy for prostate cancer: a radiation treatment planner's perspective.

INTRODUCTION: From a radiation treatment planner perspective, in the treatment of prostate cancer, inverse-planned intensity-modulated radiation therapy (IMRT) differs considerably from conventional, conformal, and forward-planned IMRT. In this work we aim to discuss the rationale behind the use of inverse-planned IMRT for the treatment of prostate cancer, as well as some of the practical aspects, including the differences in planning strategies, dose fractionation and issues in plan evaluation. DISCUSSION: The primary motivation behind the use of inverse-planned IMRT for prostate cancer radiotherapy is to attempt further dose escalation while maintaining critical structure and healthy tissue sparing at an acceptable level. The sparing of normal tissues is largely dependent on the size of the planning target volume (PTV) defined, and if the PTV overlaps critical structures. Depending on how the PTV is defined it may be impossible to achieve the desired healthy tissue sparing even with IMRT. A second role for the use of IMRT in the treatment of prostate cancer may be to conform the isodose distribution to a complex PTV, such as one that includes the seminal vesicles or the pelvic lymph nodes in the treatment volume. Finally, inverse planned IMRT may be useful in the planning and delivery of simultaneous integrated boosts where different parts of the target structures receive different daily doses. This again has applications for the simultaneous treatment of pelvic lymph nodes with the prostate treatment volume, and presents interesting opportunities for hypo-fractionation. All of these options of course require careful plan evaluation with respect to isodose distributions and dose-volume constraints as well as the radiobiological consequences of using unconventional fractionation. CONCLUSION: IMRT seems to be the most effective modality for treating complex target geometries and for delivering simultaneous integrated boosts. In particular for prostate cancer, the simultaneous treatment of the prostate and pelvic lymph nodes lends itself perfectly to IMRT, allowing the prostate to receive a higher daily dose per fraction, as well as minimizing the amount of small bowel in the field, while at the same time sparing the rectum and bladder adequately. Inverse-planned IMRT is, however, a complex procedure, and to safely implement it, an extensive patient- and machine-specific quality assurance program is required.

Dose-Response Relationship, Radiation↗
PubMed1997

The effects of spatting and ankle taping on inversion before and after exercise.

OBJECTIVE: To compare the effects of spatting, taping and spatting, taping, and not taping on the amount and rate of inversion of the ankle before and after exercise. DESIGN AND SETTING: We filmed subjects at 60 Hz while they stood on a platform that suddenly inverted the right ankle. Five trials were measured before and after a 30-minute period of drills. SUBJECTS: We tested 15 male rugby players with no history of lower-leg injury within the previous 6 months limiting activity for more than 2 days. MEASUREMENTS: The amount and rate of inversion in the four conditions were digitized and analyzed. RESULTS: The combination of spatting and taping was the most effective in reducing inversion rate and range of motion before and after exercise. CONCLUSIONS: All three taping treatments were effective in reducing the amount and rate of inversion. Exercise loosened the tape, but there may be a functional restriction of the amount and rate of inversion after exercise.

Journal Article↗
PubMed2006

Artifact simulating subarachnoid and intraventricular hemorrhage on single-shot, fast spin-echo fluid-attenuated inversion recovery images caused by head movement: A trap for the unwary.

BACKGROUND AND PURPOSE: Single-shot, fast spin-echo, fluid attenuated inversion recovery (SS-FSE-FLAIR) images are frequently used to detect disease in the brain and subarachnoid space in confused or uncooperative patients who may move during the examination. In some of these patients, high signal intensity areas are seen on good-quality images in the subarachnoid space and ventricular system in locations not associated with high CSF flow. These artifacts may simulate hemorrhage or leptomeningeal disease. The purpose of this article was to determine the cause of these artifacts, describe ways to recognize them, and find methods to reduce or eliminate them. METHODS: Healthy volunteers were studied on 6 occasions with conventional multisection FSE-FLAIR images and SS-FSE-FLAIR images while at rest and while nodding and rotating their heads at different speeds. In addition, SS-FSE-FLAIR images with different section widths of the initial inverting pulse and a non-section-selective initial inversion pulse were performed with the subjects moving their heads in the same way. The scans of 30 successive patients with acute neurologic syndromes who had been studied with SS-FSE-FLAIR sequences were reviewed for evidence of high signal intensity in the CSF in regions not associated with high CSF flow. RESULTS: Each of the volunteers showed areas of increased signal intensity in CSF at sites apart from those associated with rapid pulsatile CSF flow on SS-FSE-FLAIR images acquired during head motion. The images were otherwise virtually free of motion artifact. The use of a wider initial inversion pulse section and a non-section-selected initial inversion pulse reduced the extent of these artifacts. Nineteen of the 30 patients showed areas of high signal intensity in the CSF in regions not associated with highly pulsatile CSF flow. Six of these patients had negative lumbar punctures for blood and xanthochromia and normal CSF protein levels. CONCLUSION: High signal intensity artifacts may be seen in CSF as a result of head movement on otherwise artifact-free images when imaging uncooperative patients with SS-FSE-FLAIR sequences. These artifacts have a different mechanism and distribution from those caused by CSF pulsation and may simulate subarachnoid and intraventricular hemorrhage. Artifact recognition is aided by signs of patient motion during the examination. The artifacts can be reduced by use of increased section width and non-section-selective initial inversion pulses. Recognition of these artifacts is important, because the circumstances in which the SS-FSE-FLAIR sequence is used and the particular properties of the sequence may conspire to produce a trap for the unwary.

Adult↗
PubMedDate not supplied

Mechanistic studies on the metabolic chiral inversion of R-ibuprofen in the rat.

Deuterium labeling techniques and stereoselective GC/MS methodology have been employed to investigate the mechanism by which R-ibuprofen undergoes metabolic chiral inversion in the rat in vivo. Following oral administration of a mixture of R-ibuprofen (7.5 mg kg-1) and R-[ring-2H4; 2-2H]ibuprofen (R-[2H5]ibuprofen) (7.5 mg kg-1) to male Sprague-Dawley rats, the enantiomeric composition and deuterium excess of the drug were determined in serial plasma samples and in pooled urine collected over 10 hr. The results demonstrate that: (i) R-ibuprofen undergoes extensive inversion of configuration to its S antipode in the rat; (ii) chiral inversion of R-[2H5]ibuprofen yields S-[2H4]ibuprofen in a process that involves quantitative loss of the deuterium atom present originally at C-2; (iii) labeling of R-ibuprofen with deuterium at C-2 does not introduce a measurable kinetic deuterium isotope effect on the chiral inversion reaction; and (iv) metabolism of R-[2H5]ibuprofen leads to the appearance in plasma and urine of molecules of R-ibuprofen labeled with 4 atoms of deuterium. On the basis of these findings, a mechanism is proposed for the chiral inversion reaction that invokes the stereoselective formation of the coenzyme A thioester of R-ibuprofen as a key metabolite; conversion of this species to the corresponding enolate tautomer affords a symmetrical intermediate through which racemization of ibuprofen occurs in vivo.

Animals↗
PubMed1988

Antagonism of ethanol and pentobarbital actions by benzodiazepine inverse agonists: neurochemical studies.

The benzodiazepine inverse agonist Ro 15-4513 has been shown to antagonize several behavioral effects of ethanol and to block the effects of ethanol on chloride flux across brain membranes. We used isolated mouse brain membranes to test whether Ro 15-4513 would reduce the effects of ethanol on membrane fluidity, voltage-dependent calcium channels, microsomal calcium release or binding of t-[35S]butylbicyclophosphorothionate. None of these actions of ethanol were altered by Ro 15-4513. The enhancement of gamma-aminobutyric acid (GABA)-activated chloride flux produced by ethanol or pentobarbital was antagonized partially by Ro 15-4513. Another inverse agonist, FG 7142, was more effective than Ro 15-4513 as an antagonist of ethanol actions on chloride flux. These results demonstrate that the ethanol antagonist action of Ro 15-4513 is specific for GABA-activated chloride flux and does not extend to other neurochemical actions of ethanol. The inverse agonist action (i.e., inhibition of GABA-activated chloride flux tested in the absence of ethanol) of Ro 15-4513 and FG 7142 was revealed by pretreatment of mice in vivo with ethanol. This raises the possibility that ethanol exposure increases the inverse agonist actions of Ro 15-4513 and related drugs and that these inverse agonist actions contribute to the ethanol antagonism observed in vivo and in vitro.

Animals↗
PubMed1985

Cytomegalovirus infection in cardiac transplant recipients associated with chronic T cell subset ratio inversion with expansion of a Leu-7+ TS-C+ subset.

Lymphocyte subsets were analysed in 18 patients during the first 3 years after cardiac transplantation. The patients received Cyclosporin A and prednisolone for maintenance immunosuppression. Serological evidence of active cytomegalovirus (CMV) infection was found in 13 cases (72%), and in 12 of these an inversion usually of the T helper/T suppressor-cytotoxic ratio (TH/TS-C) was detected. T subset inversion usually preceded the diagnostic rise in CMV antibody titre. In 69% of patients with CMV the TH/TS-C ratio remained inverted throughout follow-up (245-951 days). Persistent T subset inversion was not found in all five patients who lacked serological evidence of active CMV. Chronic inversion consisted of an average increase in TS-C of 152% and an average decline in TH cells of 31% as compared to CMV negative patients. The proportion of lymphoid cells reacting with a phenotypic marker for natural killer (NK) cells (Leu-7) was increased by 83%. These alterations were also reflected in the absolute numbers of cells with these markers. Two-colour immunofluorescence analysis revealed that the expanded TS-C population present during chronic inversion was predominantly Leu-7+. As TS-C+ Leu-7+ cells in healthy persons may be hyporesponsive NK cells, a sustained increase in this cell type in allograft recipients could further reduce immunocompetence, thereby predisposing to superinfection or malignancy.

Adult↗