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Biomedical subjects

B Jones

Publications and source records attributed to B Jones.

At least 469 records · Page 26Linked to original sources
PubMed1986

Hypothalamic-pituitary function of children with acute lymphocytic leukemia after three forms of central nervous system prophylaxis. A retrospective study.

The hypothalamic-pituitary function of 93 children, who had received central nervous system (CNS) prophylaxis as part of their therapy for acute lymphocytic leukemia (ALL), and who remained in continuous complete remission, was evaluated retrospectively. Treatment regimens included--Group I: 31 subjects, intrathecal methotrexate (IT MTX); Group II: 31 subjects, IT MTX plus 2400 rad cranial irradiation; and Group III: 31 subjects, IT MTX and intravenous intermediate-dose methotrexate. Serum thyroid-stimulating hormone (TSH) and T4 levels were normal. All participants had normal adrenocorticotropic hormone (ACTH) secretion as assessed by plasma cortisol responses to insulin hypoglycemia. Urinary follicle-stimulating hormone (FSH) and luteinizing hormone (LH) excretion of pubertal and postpubertal patients (N = 37) was appropriate, except for one subject from Group I who had an abnormally high output of gonadotropins, and one from Group II who had abnormally low levels. Growth hormone (GH) responses were subnormal after sequential arginine-insulin stimulation as follows--Group 1: 3 of 31 patients; Group II: 6 of 25 patients; and Group III: 2 of 29 patients. Nevertheless, all children had normal linear growth. It was concluded that the three forms of CNS prophylaxis evaluated had no long-term adverse effect on TSH and ACTH secretion. FSH-LH production appears to be normal, but final judgment must await follow-up studies because 60% of the patients were prepuberteral or still receiving chemotherapy. Eleven patients had subnormal GH responses after pharmacologic stimulation of the pituitary, but long-term linear growth was unaffected.

Adolescent↗
PubMed1986

Virulence of tubercle bacilli isolated from patients with tuberculosis in Bangalore, India.

This is a study of the virulence of cultures of Mycobacterium tuberculosis isolated from pulmonary and extrapulmonary forms of tuberculosis in patients living in or near Bangalore, India. The findings are as follows: 1. The percentage of cultures recovered from cases of pulmonary tuberculosis in Bangalore classified as being of low, moderate, and high virulence, was the same as that reported by Mitchison et al., in 1960 for isolates obtained from patients in Madras, India. 2. The distribution of the root index of virulence (RIV) of isolates from patients living in the city of Bangalore was significantly different (p less than 0.05) from that of isolates from patients living in rural Bangalore. 3. Even though the number of cultures classified as high virulent was significantly greater in isolates from patients with tuberculosis meningitis compared with those from patients with pulmonary tuberculosis, the data show that 36% of the isolates from the meningitis group were classified as low virulent.

Humans↗
PubMed1986

EEG alpha activity increases during transient episodes of ethanol-induced euphoria.

The effects of acute ethanol administration were studied in 18 men to determine the electroencephalographic (EEG) correlates of ethanol-induced behavioral changes. Subjects were instructed to operate an instrumental device to indicate changes in their subjective mood state while EEG activity and plasma ethanol levels were continuously measured. Three groups of 6 subjects consumed either placebo, 0.347 g/kg ethanol or 0.695 g/kg ethanol over a 15 min period. EEG and behavioral changes were directly correlated with plasma ethanol levels during the ascending limb of the plasma ethanol curve. Theta EEG activity increased proportionally as plasma ethanol levels increased during the 2 hr recording session. Alpha EEG activity increased during the first hour and then returned to control levels. The increased alpha activity was most prominent when subjects reported feeling intense pleasure or euphoria. Power spectral analysis of discrete samples of EEG activity revealed that transient increases in alpha activity paralleled the onset of ethanol-induced euphoria. These data suggest that ethanol-induced behavioral effects are associated with discrete changes in brain electrical activity.

Adult↗
PubMed1986

Computed tomography findings in gastrointestinal involvement by opportunistic organisms in acquired immune deficiency syndrome.

The computed tomography findings in two cases of gastrointestinal superinfection by opportunistic organisms in acquired immune deficiency syndrome are presented. Findings included thickening of the mucosal folds and the bowel wall in the small intestine and colon associated with cytomegalovirus and cryptosporidiosis. These cases indicate that it is important to look carefully at the gastrointestinal tract when performing computed tomography in this group of patients. Unsuspected bowel pathology may be demonstrated, or disease may be confirmed in clinically suspected cases.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Perception of texture by vision and touch: multidimensionality and intersensory integration.

A series of six experiments offers converging evidence that there is no fixed dominance hierarchy for the perception of textured patterns, and in doing so, highlights the importance of recognizing the multidimensionality of texture perception. The relative bias between vision and touch was reversed or considerably altered using both discrepancy and nondiscrepancy paradigms. This shift was achieved merely by directing observers to judge different dimensions of the same textured surface. Experiments 1, 4, and 5 showed relatively strong emphasis on visual as opposed to tactual cues regarding the spatial density of raised dot patterns. In contrast, Experiments 2, 3, and 6 demonstrated considerably greater emphasis on the tactual as opposed to visual cues when observers were instructed to judge the roughness of the same surfaces. The results of the experiments were discussed in terms of a modality appropriateness interpretation of intersensory bias. A weighted averaging model appeared to describe the nature of the intersensory integration process for both spatial density and roughness perception.

Adolescent↗
PubMed1986

Peptic ulcer in rheumatoid arthritis--intrinsic or related to drug therapy?

The reported incidence of peptic ulcer disease (PUD) in patients with rheumatoid arthritis (RA) is higher than that of the general population. Unusual susceptibility to PUD in RA, independent of therapy, has been suggested. To compare RA patients with others who had similar drug exposure but no known predisposition to PUD, 120 patients hospitalized for treatment of severe arthritis (65 with RA, 55 with osteoarthritis) were assessed by questionnaire for PUD history, drug history and other relevant variables. The relationship of PUD to sex distribution, smoking, alcohol consumption and anti-inflammatory therapy followed expected patterns. We found high but similar PUD rates in RA and osteoarthritis (OA) patients (RA 15%, OA 18%). This suggests that a common factor (probably drugs) is responsible. We feel that the documented high incidence of PUD in RA is most probably related to drug therapy. Available methods cannot determine if PUD ever occurs as a primary manifestation of RA.

Aged↗
PubMed1986

Purification and physiochemical properties of a recombinant bovine growth hormone produced by cultured murine fibroblasts.

Mouse fibroblast cell lines which secrete bovine (b) GH have been generated. This was accomplished by cotransforming mouse L cells (thymidine kinase-negative [TK-] and adenine phosphoribosyl transferase-negative [APRT-]) with DNA molecules encoding the Rous sarcoma virus-long-terminal repeat and bGH genes along with the herpes viral TK gene and the hamster APRT gene. One stable cell line, Pd lambda-pbGH 4-13, was found to secrete approximately 75 micrograms bGH per 24 h/5.0 X 10(6) cells. Media from this cell line were collected for purification of recombinant bGH (rbGH). Purification involved (NH4)2SO4 fractionation, ion-exchange chromatography, and gel filtration on Sephacryl S-200. The rbGH was characterized by bioassay, RIA, radioreceptor assay, and sodium dodecyl sulfate gel electrophoresis. Results of these analyses were compared with those obtained with a highly purified pituitary bGH. In the rat tibia bioassay, rbGH was found to be as potent as pituitary bGH. Results from the RIA, radioreceptor assay, and sodium dodecyl sulfate gel electrophoresis and Western blot analysis also suggested that the rbGH was similar to that of pituitary origin. Amino acid composition, partial (amino-terminal) sequence, and tryptic peptide maps were also found to be similar between the rbGH and pituitary bGH preparations. The amino terminus of the rbGH showed similar heterogeneity to that of the bGH of pituitary origin. We conclude that rbGH which was synthesized, processed, and secreted from transformed mouse fibroblasts possessed almost exactly the same physiochemical properties as pituitary bGH.

Amino Acids↗
PubMed1986

Computed tomography of gastrointestinal inflammation after bone marrow transplantation.

Overwhelming secretory diarrhea can be a major complication after bone marrow transplantation, associated usually with acute graft-versus-host disease (AGVHD). Radiographic evaluation may be hampered by nausea, vomiting, or debilitation. Computed tomography (CT) in seven such patients demonstrated diffuse wall thickening in the small intestine, colon, and/or mesentery. In two cases, prolonged adherence of oral contrast material to the luminal surface resulted in bizarre patterns of coating. In two others, a layer of low attenuation within the thickened wall produced a target appearance consistent with submucosal edema or hemorrhage. Small bowel dilatation and fold enlargement was the only finding in one patient. The role that superinfection of the gastrointestinal tract with opportunistic organisms can play in this immunocompromised group of patients is less well established. In this group of patients, the findings were due to AGVHD in two, AGVHD and viral enteritis in two, and viral enteritis alone in three. CT may be an alternative to routine contrast studies in assessing the extent of gastrointestinal tract involvement after bone marrow transplantation. Neither contrast studies nor CT were able to differentiate between AGVHD and viral enteritis.

Adolescent↗
PubMed1986

Small-bowel diverticulitis: CT findings.

Three patients with subsequently proven small-bowel diverticulitis were studied with preoperative CT. In all three cases, an inflammatory mass was present, two involving the terminal ileum and cecum and one involving the jejunum. While the findings in the two cases of ileal diverticulitis simulated appendicitis, in the case of jejunal diverticulitis the diagnosis was suggested on the basis of CT findings. Small-bowel diverticulitis should be included in the differential diagnosis if an inflammatory mass involving the small bowel is demonstrated on CT.

Aged↗
PubMed1986

Different phenotypic variants of the mouse B cell tumor A20/2J are selected by antigen- and mitogen-triggered cytotoxicity of L3T4-positive, I-A-restricted T cell clones.

The L3T4+, Lyt-2-, cloned BALB/c T cell lines 5.9.24 and 5.8.6 are cytotoxic for the BALB/c B cell tumor line A20/2J. The T cell cytotoxicity against A20/2J cells could be triggered either by the specific antigen ovalbumin (OVA), which is recognized by the T cell clones in association with I-Ad determinants, or by the T cell mitogens Con A and rabbit anti-mouse brain (RaMBr) antiserum. Repeated exposure of A20/2J cells to 5.9.24 and 5.8.6 T cell cytotoxicity selected variant cell lines that had developed resistance to cytotoxicity. The variant lines could be classified into four different variant phenotypes of which three were stably maintained in vitro. The type of variant obtained appeared to be related to the nature of the ligand used to trigger T cell cytotoxicity during selection. Cytotoxicity triggered by the antigen OVA generated type 1 variants that expressed abnormally low levels of I-Ad determinants at the cell surface. Type 1 variants were resistant to OVA-triggered 5.9.24 T cell cytotoxicity, but were fully susceptible to cytotoxicity triggered by Con A or RaMBr antiserum. RaMBr-triggered cytotoxicity generated two unique types of variant cell lines: type 3 variants that were deficient in cell surface Fc receptors and resistant to 5.9.24 cytotoxicity only when triggered by RaMBr antiserum, and type 4 variants that were resistant to cytotoxicity triggered by all three ligands. One type 4 variant, the IC-1 cell line, appeared to be resistant to soluble cytotoxic factors released by 5.9.24 T cells after activation by antigen. All of these variant lines retained sensitivity to cytotoxicity by classic Lyt-2+ cytotoxic T lymphocytes (CTL), a finding that indicates that L3T4a+ T cells and Lyt-2+ CTL use different molecules to attack their target cells. The variant phenotypes were inherited by clones derived from the original cell lines. Because the variants were generated without mutagenesis, they are thought to have been derived by the immunoselection of pre-existing variant cells that arose spontaneously in the parental A20/2J cell line. It is postulated that inheritable variation of A20/2J cells may represent changes that normally occur during B cell differentiation in response to T cell signals. The variant A20/2J cell lines described here provide material for the investigation of B cell surface structures that may regulate T-B cell interactions.

Animals↗
PubMed1986

Cell interactions in the immune system: the role of self recognition in the targeting of nonspecific effector molecules by helper T cells.

Helper T cells are activated by cross-linking of their receptors by antigen:Ia complexes on the surface of antigen-presenting cells and B cells. As a result of this cross-linking, the helper T cell releases several lymphokines that in turn affect the Ia-bearing cell with which the helper T cell is in contact. This interaction is cognate when the effect on the target cell is examined, but it operates by a mechanism that is neither antigen specific nor MHC restricted. Whether the cognate nature of this interaction reflects solely the intimate contact of the T cell with the Ia antigen-bearing cell or whether it reflects a receptor-directed focal release of lymphokines remains to be determined. The molecular basis for functional diversity in helper T cells will have to be determined by examining the factors that regulate lymphokine gene expression in such cells, a process that appears to act at several levels.

Animals↗
PubMed1986

Immunological abnormalities in asymptomatic homosexual men: correlation with antibody to HTLV-III and sequential changes over two years.

A prospective study on 100 homosexual male volunteers was designed to examine immunological function in relation to sexual activity and infection with the human T cell lymphotropic virus Type III (HTLV-III). Complete data were available for 71 men. In a comparison with 100 age-matched heterosexual men, the study group of 100 men had a significantly higher mean serum IgG level (12.1 +/- SD 2.7 g/l vs. 10.9 +/- 2.4 g/l, p less than 0.01) and a significantly lower mean number of CD4 (T4) cells (845 +/- 310 X 10(-6)/l vs. 1128 +/- 375; p less than 0.01). For the study group, seropositivity for anti-HTLV-III was present initially in 22 per cent and was associated with a higher mean level of serum IgG and lower mean number of CD4 cells. Among seropositive homosexual men a low CD4/8 ratio was attributable to low numbers of CD4 cells in those without lymphadenopathy and to high numbers of CD8 cells in those with lymphadenopathy. For the seronegative homosexual men, a low CD4/8 ratio as a result of an increased CD8 cell count was present in 12 of 60, and was associated with numerous sexual partners and semen culture positive for cytomegalovirus. In two seropositive subjects a low CD4/8 ratio due to a decrease in the CD4 cell count was predictive of the development of AIDS by some two years. For the 71 men with complete data over two years, indices of cell-mediated immunity, including mean counts of CD4 cells, the CD4/8 ratio, and score for recall of cutaneous delayed type hypersensitivity increased during the first year but not during the second year in both seropositive and seronegative subjects. These increases occurred in association with changes in sexual practices and activity, but could not be attributed to any one particular factor.

AIDS-Related Complex↗
PubMed1986

Stress examination of traumatized lateral ligaments of the ankle.

In the diagnostic analysis of acute injury to the lateral ankle ligaments, ankle arthrography and plain film stress examination play an important role. Inasmuch as the treatment of choice, whether conservative or surgery, and insofar as the therapeutic results may be determined by the extent of injury, it is important to have access to quantitative information on the functional properties of the involved ligaments at the time of the initial diagnostic studies. This can be obtained by measuring the strain on the anterior talofibular (tf) and calcaneofibular (cf) ligaments as a function of pressure applied to the distal tibia. Any device that ensures that the externally applied pressure is proportionally carried through to the ligaments can be used for this purpose. The results of 25 quantitative stress examinations using a Telos stress device are compared with arthrography findings and findings at surgery. Stress examination correlates well with both arthrographic and operative findings. The method is also useful for the evaluation of chronic ankle instability, follow-up examinations, and for the detection of vestiges of previous trauma of the contralateral ankle. The procedure is straightforward and noninvasive and can be performed within 15 minutes.

Adult↗
PubMed1985

Computerized tomography scan findings in children with acute lymphocytic leukemia treated with three different methods of central nervous system prophylaxis.

Computerized tomography (CT) scans of the head were done on 93 children with acute lymphocytic leukemia in continuous complete remission who had been randomly assigned to three different methods. of central nervous system (CNS) prophylaxis. Twenty-nine children had received six doses of intrathecal methotrexate, 30 had received six doses of intrathecal methotrexate plus 2400 rad of cranial irradiation, and 34 had received six doses of intrathecal methotrexate plus three courses of intermediate-dose intravenous methotrexate. The overall incidence of abnormal scans was 35%, of which 91% were felt to represent minimal abnormalities. CT scan abnormalities were noted in 30% of the children receiving intrathecal methotrexate only, in 40% of those receiving intrathecal methotrexate plus cranial irradiation, and in 35% of those receiving intrathecal methotrexate plus intermediate dose methotrexate. These differences were not statistically significant. None of the three methods of CNS prophylaxis resulted in significant CT scan abnormalities. However, the few moderately or markedly abnormal scans evaluated were restricted to patients who received intrathecal methotrexate plus cranial irradiation. The clinical significance of CT scan abnormalities in leukemic children receiving these treatments remains unclear.

Brain Neoplasms↗