PubMed Health⌕ Search

Biomedical subjects

D J Quint

Publications and source records attributed to D J Quint.

At least 19 recordsLinked to original sources
PubMed1992

Case report 712: Hemorrhagic synovial cyst arising from right L2-3 facet joint.

Synovial cysts are a common complication of osteoarthritis in the lumbar spine, causing pain and neurological symptoms. However with early diagnosis a good clinical result can be expected. This report describes a documented case of hemorrhage into a synovial cyst demonstrated on both MR and CT imaging and summarizes the relevant diagnostic features. The sites of origin of such a synovial hemorrhagic cyst are described and its relationship to an arthritic facet joint is stressed.

Hemorrhage↗
PubMed1992

Alexia without agraphia.

Two new cases of alexia without agraphia are presented. Pertinent clinical findings, anatomy, pathophysiology and differential diagnoses are reviewed. The importance of carefully examining the inferior portion of the left side of the splenium of the corpus callosum on CT and/or MR scans in patients who present with this clinical syndrome is stressed.

Aged↗
PubMed1992

A quantitative assessment of the addition of MRI to CT-based, 3-D treatment planning of brain tumors.

Quantitative 3-D volumetric comparisons were made of composite CT-MRI macroscopic and microscopic tumor and target volumes to their independently defined constituents. Volumetric comparisons were also made between volumes derived from coronal and axial MRI data sets, and between CT and MRI volumes redefined at a repeat session in comparison to their original definitions. The degree of 3-D dose coverage obtained from use of CT data only or MRI data only in terms of coverage of composite CT-MRI volumes was also analyzed. On average, MRI defined larger volumes as well as a greater share of composite CT-MRI volumes. On average, increases in block margin on the order of 0.5 cm would have ensured coverage of volumes derived from use of both imaging modalities had only MRI data been used. However, the degree of inter-observer variation in volume definition is on the order of the magnitude of differences in volume definition seen between the modalities, and the question of which imaging modality best describes tumor volumes remains unanswered until detailed histologic studies are performed. Given that tumor volumes independently apparent on CT and MRI have equal validity, composite CT-MRI input should be considered for planning to ensure precise dose coverage for conformal treatments.

Astrocytoma↗
PubMed1992

CT of scoliotic patients after myelography: value of lateral decubitus positioning.

In routine computed tomography (CT) of scoliotic patients, multiple scans through each intervertebral disk level must be made, which can make interpretation of disks and neural foramina difficult. Use of lateral decubitus positioning for postmyelography CT allows use of gantry angulation to achieve true axial scans through disks, which permits easier evaluation of individual disks and foramina.

Humans↗
PubMed1992

Absence of the carotid canals at skull base CT.

Congenital absence of one or both internal carotid arteries (ICAs) has a high association with circle of Willis aneurysm formation. Since the carotid canals in the skull base form secondary to the presence of the embryonic ICA, absence or hypoplasia of a carotid canal on a computed tomographic (CT) scan through the skull base should suggest a congenital ICA abnormality and prompt a search for associated intracranial vascular abnormalities. Of four patients with carotid canal underdevelopment evident at CT, two had associated circle of Willis aneurysms and a third had an extensive skull base rete mirabile supplying an abnormal tangle of vessels in the basal cisterns. Only two patients (one with an aneurysm, one with the skull base rete mirabile) presented with subarachnoid hemorrhage. One patient presented with monocular decreasing vision due to an enlarging aneurysm, and one patient was essentially asymptomatic. If asymmetry or absence of the carotid canals is evident on CT scans of the head, further evaluation to rule out a potentially life-threatening intracranial vascular abnormality such as those found in these patients should be seriously considered, even in a young or asymptomatic patient.

Aged↗
PubMed1990

Amyloidosis of the spine in a patient on long-term hemodialysis.

A 54-year-old man with a history of renal failure treated with hemodialysis for over 10 years presented with clinical signs and symptoms and plain radiographic, computed tomographic and magnetic resonance imaging features of cervical vertebral osteomyelitis with spinal cord compression. Decompressive surgery revealed amyloid deposition. In the setting of chronic hemodialysis, differentiation between amyloid deposition and osteomyelitis may not be possible on an imaging basis necessitating biopsy for diagnosis.

Amyloidosis↗
PubMed1990

In vitro and in vivo studies with purified recombinant human interleukin 5.

The functional activities of highly purified recombinant human IL 5 (hIL 5) have been characterized on a number of cell types in vitro and in BALB/c mice in vivo. In vitro, hIL 5 could induce the differentiation of eosinophils from precursors in both human and mouse bone marrow with approximately the same efficiency. A mouse IL 5/3-dependent B cell line, LyH7.B13, was found to proliferate in response to hIL 5 but not human interleukin 1 (IL 1), interleukin 2 (IL 2), interleukin 3 (IL 3), interleukin 4 (IL 4), interleukin 6 (IL 6), interferon-gamma (IFN-gamma), or granulocyte macrophage-colony stimulating factor (GM-CSF) and was at least 10-fold more sensitive than BCL1 mouse lymphoma cells. We have successfully used this cell line to demonstrate the production of IL 5 by human T cell clones. In marked contrast to its effects on murine B cell lines, hIL 5 had no demonstrable activity on CD23 expression, anti-mu costimulated proliferation or IgM, IgG, or IgE production by tonsillar B cells and did not influence such responses triggered by IL 4. BALB/c mice injected with hIL 5 for 7 consecutive days were shown to develop an eosinophilia comparable to that induced by infection with the parasite Mesocestoid corti.

Animals↗
PubMed1990

Magnetic resonance demonstration of vertebral artery dissection. Report of two cases.

Vertebral artery dissection may be spontaneous or related to some traumatic event. Diagnosis has usually been made by angiography, an invasive procedure with certain well-known risks. The authors describe the magnetic resonance (MR) appearance (both on conventional spin-echo and on gradient refocused "flow" sequences) in two patients with vertebral artery dissection confirmed by angiography. It is proposed that the less invasive MR imaging might be the imaging modality of choice for initial evaluation of suspected vertebral artery dissection.

Adult↗
PubMed1990

Immunoregulation in the common marmoset, Calithrix jaccus: functional properties of T and B lymphocytes and their response to human interleukins 2 and 4.

Non-human primates have been used to study immune function to a much lesser extent than readily available strains of inbred rodents. Nevertheless, in situations where it might be desirable, but impossible, to study human immune responses in vivo, lower primates could provide an acceptable alternative. In order to extent the knowledge of T- and B-lymphocyte function in lower primates, the common marmoset Callithrix jaccus was used as an experimental model. The functional similarities between this species and humans at the level of T-B co-operation in the antibody response were examined, and xenoreactive T-lymphocyte clones were obtained from marmoset spleen cells using Epstein-Barr virus (EBV)-transformed human B cells as stimulators. These clones could act as helper cells when co-cultured with human B lymphocytes, inducing the secretion of both IgM and IgG. Lymphokine production by mitogen-stimulated marmoset T-cell clones was also examined. Interleukins (IL) 2 and 4 activities were detected in clone supernatants using bioassays and interferon-gamma (IFN-gamma) was detected using a solid-phase ELISA system. However, SDS-PAGE analysis of biosynthetically labelled marmoset and human T-cell clone supernatant proteins revealed major differences between the soluble T-cell products of the two species. The proliferative responses of marmoset T and B cells to recombinant human IL-2 and IL-4 were also examined. Stimulation of [3H]thymidine uptake was detected in both T cell- and anti-IgM-stimulated B-cell cultures with both of the lymphokines. These results suggests that the key components of the antibody response are functionally conserved between lower primates and man and that the common marmoset may be useful as an in vivo model of immune function, particularly with regard to the role of interleukins such as IL-2 and IL-4.

Animals↗
PubMed1989

Functional and phenotypic properties of T-cell clones which regulate IgE synthesis.

We have generated a panel of T-lymphocyte clones from a patient suffering from the hyper IgE syndrome, and have attempted to correlate the ability of each to help IgE responses in vitro with the profile of lymphokines secreted after mitogenic stimulation. Clones which showed positive IgE helper activity released larger amounts of interleukin-4 (IL-4) than the non-helpers, which tended to release more interleukin-2 (IL-2). Surprisingly, all clones released moderate amounts of gamma interferon (IFN), which has been shown to inhibit the action of IL-4 on B cells. The clones were analysed by indirect immunofluorescence using monoclonal antibodies to CDw29 and CD45R (4B4 and 2H4 respectively). Those T cells which could provide strong helper activity for all isotypes, expressed high levels of CDw29 and low CD45R. These data suggest that these CD4-positive T cells expressing surface antigen of the 'memory' subset i.e. CDw29, are involved in IgE isotype regulation by virtue of their ability to secrete IL-4 upon antigenic stimulation.

Antigens, Differentiation↗
PubMed1989

Intraluminal clot in the vertebrobasilar circulation: clinical and radiologic features.

We studied 15 patients with angiographically documented intraluminal clot in the vertebrobasilar (VB) circulation and ischemic stroke. Progressive brainstem signs were the most common presentation; the neurologic deficit was maximum at stroke onset in 4. Seven experienced their first symptoms during sedentary activities. Thirteen of the initial 15 CTs revealed infarcts in the VB territory, 7 with multiple foci. Intraluminal clot was present in the vertebral artery in 7 patients (2 bilateral), basilar artery in 7, posterior cerebral artery in 5, and superior cerebellar artery in 1. Multiple clots were seen in 5 patients. Stroke risk factors were present in the majority of cases. Although cardiac source embolism was the most common single etiology (4 patients), most patients had other causes including migraine, coagulopathy associated with malignancy and nephrotic syndrome in systemic lupus erythematosus, vertebral artery dissection with local embolism, delayed irradiation arteriopathy, and a fusiform, ectatic basilar artery. Six (40%) died within 5 months of follow-up. Intraluminal clot in the posterior circulation is a marker for multiple stroke mechanisms, not all of which are embolic. Intraluminal clot should prompt investigations into occult risk factors when no cause appears obvious.

Adult↗
PubMed1989

Functional and phenotypic analysis of human T-cell clones which stimulate IgE production in vitro.

Peripheral blood mononuclear cells (PBMC) from a patient suffering from the hyper IgE syndrome were used to generate phytohaemagglutinin (PHA)-expanded T-cell clones (all CD4+, CD8-, CD23-). A selection of the clones was tested for their ability to help IgE secretion by culturing with normal B cells in the presence of solid-phase antibody to CD3. Supernatants were harvested on Day 7 and assayed by ELISA for IgE, IgG and IgM. Lymphokine secretion by the clones was assessed by culturing clones for 24 hr with solid-phase antibody to CD3 followed by assay of the supernatants for IL-2, IL-4 and interferon-gamma (IFN-gamma) production. In addition, clones were analysed by flow cytometry for CDw29 and CD45R expression. Initial experiments with seven clones indicated that those clones that could help IgE secretion also stimulated optimal IgG and IgM responses. All clones appeared to secrete IL-2, IL-4 and IFN-gamma, although the amounts of each varied. These results confirm recent findings that human T-cell clones do not fall into Tinf (Th1) and Th (Th2) type subsets as described in the mouse. There was no clear correlation between the lymphokines secreted by the clones and their capacity to help IgE production. However, the helper function of the clones for all isotypes, including IgE, appeared to be related to the level of expression of the surface antigen CDw29.

Antigens, Differentiation↗
PubMed1988

Epidural lipomatosis.

The authors report six new cases of epidural lipomatosis--a rarely described entity characterized by increased extradural fat within the spinal canal causing compression of the spinal cord and neurologic deficits. Five of the six patients had a history of chronic steroid use. Myelography of the thoracic spine, followed by computed tomography (CT), was performed in five patients, and magnetic resonance (MR) imaging was done in three. Myelographic findings were abnormal in three patients and normal in two, compared with those of postmyelography CT, which revealed increased accumulation of extradural fat in all five patients. In the three patients in whom it was performed, MR imaging also showed the increased spinal canal fat. Four patients underwent surgery, which revealed an increased amount of histologically normal, unencapsulated fat in all cases. The diagnosis of epidural lipomatosis should be based on a combination of clinical, imaging, surgical, and histologic findings. If the clinical suspicion is high, even if results of myelography are normal, further evaluation with post-myelography CT or MR imaging should be considered.

Adult↗