Biomedical subjects
Publications and source records attributed to M Feldman.
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Tumors of the musculoskeletal system are relatively rare. They occur mostly in the young, while in older age groups metastases and myeloma are more prevalent. Treatment has undergone major change in the past 20 years with the introduction of neoadjuvant treatment protocols. According to recent reports 5-year survival rates have increased from 20% to 60-70%. These new protocols involve the use of modern imaging modalities, immunohistochemical pathological analysis and improved surgical technics. This has required establishment of multidisciplinary teams of experts to escort the patient through all the steps of current treatment.
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The cellular requirements for generating potent human CD8+ CTLs to influenza A virus in vitro have been defined. Furthermore, we have developed improved methods for generating large numbers of DCs from non-proliferating progenitors. These developments have enabled the design of new strategies to elicit CTLs in vivo. For example, together with IL-12, antigen-pulsed DCs may be a useful approach for boosting CTL responses against infectious agents and malignancies. Our results also reopen the potential use of inactivated virus preparations as immunogens for CTL responses.
Hepatosplenic gammadelta T cell lymphoma (TCL) is a rare, aggressive subset of peripheral TCL that presents with hepatosplenomegaly and cytopenias. Detailed clinicopathological, ultrastructural, and cytogenetic analyses of these lymphomas are limited; functional characteristics of these lymphomas are unknown. We have undertaken a clinicopathological, immunophenotypic, ultrastructural, cytogenetic, and functional analysis of three hepatosplenic gammadelta TCLs. All patients presented with massive hepatosplenomegaly and anemia, thrombocytopenia, or severe neutropenia; terminal blastlike transformation occurred in one patient. Combination chemotherapy had no response in two patients, but induced complete remission in one. gammadelta T cell receptor (TCR) expression and clonal TCRdelta gene rearrangements were documented in each case. Two different subsets of gammadelta TCL were identified based on delta chain variable region usage; two lymphomas were Vdelta1+, whereas the third was negative for both Vdelta1 and Vdelta2. Cytogenetic analysis was performed on two lymphomas; isochromosome 7q and probable trisomy 8 was shown in one of the Vdelta1+ lymphomas, whereas the Vdelta1 negative lymphoma had 14p+ with t(1;14)(q21;p13). NK cell-associated antigens (CD11c, CD16, or CD56) and cytotoxic T lymphocyte (CTL) effector proteins (perforin, granzyme B, TIA-1, and Fas ligand) were expressed by each lymphoma; dense core cytolytic granules were observed by electron microscopy in both lymphomas studied. Functional studies performed in two cases showed TCR-mediated cytolysis of P815 x 2 FcR+ cells induced by anti-CD3 in a redirected cytolysis assay in one of the CD56+, Vdelta1+ lymphomas, whereas IFNgamma secretion was induced by anti-CD3 in the CD56-, Vdelta1 negative lymphoma. These studies show that hepatosplenic gammadelta TCLs have CTL differentiation, retain functional activity in vitro, and are derived from at least two gammadelta T cell subsets.
The complementary nature of anion exchange chromatography and capillary gel electrophoresis for oligonucleotide analysis is demonstrated by evaluating a comprehensive series of authentic deletion sequences and partial phosphodiester analogs of five phosphorothioate oligonucleotides of different base composition and sequence. While anion exchange HPLC is sensitive to differences in backbone length of phosphorothioate oligonucleotides, oligomers with length difference of one base unit are not resolved. Capillary gel electrophoresis, on the other hand, has excellent single-base resolution while being relatively insensitive to phosphate in the phosphorothioate backbone. The data definitively establish the necessity of employing both separation techniques for adequate characterization of lower order process-related impurities potentially found in synthetic phosphorothioate oligonucleotides.
Function following stroke is often measured using the Functional Independence Measure (FIM). Independence occurs when the patient achieves certain levels of functions. SPECT imaging assesses the regional cerebral blood flow (rCBF). Is it possible to correlate the FIM scores with SPECT imaging and predict functional return? We evaluated total of 69 stroke patients with SPECT imaging using Iofetamine (I-123). Patients were scanned within 14-21 days post-stroke. CT scans were evaluated and correlated with the SPECT images. This information was compared with the admission and discharge FIM scores. The rCBF reperfusion changes and region of stroke were evaluated and correlated with discharge functional status. The right parietal areas demonstrated a strong correlation with SPECT and FIM changes as predictors of return of functional living status (p-value = 0.0438). The right parietal area demonstrated an improvement in ambulation (p-value = 0.0578); the right brain correlated with overall improvement in FIM scores and change in SPECT imaging (p-value = 0.0833); the left brain did not exhibit significant values. Our conclusion was that there were trends seen with the predictive value of stroke recovery using SPECT imaging. The current sample number was not large enough to provide an adequate study, especially for the left brain; a larger study is needed. This information could be useful to help determine patient placement for rehabilitation.
To study genome evolution in allopolyploid plants, we analyzed polyploid wheats and their diploid progenitors for the occurrence of 16 low-copy chromosome- or genome-specific sequences isolated from hexaploid wheat. Based on their occurrence in the diploid species, we classified the sequences into two groups: group I, found in only one of the three diploid progenitors of hexaploid wheat, and group II, found in all three diploid progenitors. The absence of group II sequences from one genome of tetraploid wheat and from two genomes of hexaploid wheat indicates their specific elimination from these genomes at the polyploid level. Analysis of a newly synthesized amphiploid, having a genomic constitution analogous to that of hexaploid wheat, revealed a pattern of sequence elimination similar to the one found in hexaploid wheat. Apparently, speciation through allopolyploidy is accompanied by a rapid, nonrandom elimination of specific, low-copy, probably noncoding DNA sequences at the early stages of allopolyploidization, resulting in further divergence of homoeologous chromosomes (partially homologous chromosomes of different genomes carrying the same order of gene loci). We suggest that such genomic changes may provide the physical basis for the diploid-like meiotic behavior of polyploid wheat.
OBJECTIVE: This research investigates personality variables--aggression and disorders of conduct, depression, and separation anxiety--mediating suicidal behavior in psychiatrically hospitalized urban minority adolescents. METHOD: Four matched groups of 26 subjects (N = 104) participated: suicidal adolescents with, and suicidal adolescents without, a conduct disorder diagnosis, nonsuicidal adolescents with a conduct disorder diagnosis, and a nonpsychiatric control group. Subjects were assessed with three dimensions from the Epigenetic Assessment Rating System (EARS), the Children's Depression Inventory (CDI), and the Separation Anxiety Test (SAT). RESULTS: A conduct disorder diagnosis was related to lower modal EARS scores. The EARS and the CDI each identified a different subset of suicidal adolescents. Adolescents with lower modal EARS scores exhibited greater reactivity to separation experiences on the SAT. CONCLUSION: Relying on depressive symptomatology to identify suicidality overlooks a majority of at-risk adolescents. Structural personality variables as measured by the EARS identify and distinguish subsets of suicidal adolescents.
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The statistical and practical implications of including second eye surgeries were examined in a clinical trial designed to evaluate the impact of routine preoperative testing prior to cataract surgery on major medical events occurring within seven days following surgery. In order to detect a 0.8% difference in the rates of rare major medical events between the tested and untested groups, 20,000 surgeries must be randomized. About 30% of cataract operations were estimated to be done on second eyes of patients already included in the cohort. Different options for dealing with second eye surgeries were: (1) exclusion of all second eye surgeries, (2) inclusion of second eye surgeries only if the first eye is not enrolled, (3) inclusion of first and second eyes but randomization of patients rather than eyes, and (4) inclusion of first and second eyes but randomization of surgeries rather than patients. The final decision was to exclude second eye surgeries done within 28 days of first eye surgeries, but to rerandomize all other second eye surgeries. Differences in event rates between treatment groups can be estimated using Generalized Estimating Equations, and the association between outcomes of first and second eye operations estimated with pairwise odds ratios. An anticipated small positive correlation is likely to have minimal impact on statistical power and effective sample size.
The author emphasises that what is projected into the analyst is a phantasy of an object relationship that evokes not only thoughts and feelings, but also propensities towards action. From the patient's point of view, the projections represent an attempt to reduce the discrepancy between the phantasy of some archaic object relationship and what the patient experiences in the analytical situation. For the analyst, too, there are impulses to function in ways that lead to a greater correspondence with some needed or desired phantasies. The interaction between the patient's and the analyst's needs may lead to the repetitive enactment of the painful and disturbing kind that is described. It may be very difficult for the analyst to extricate himself (or his patient) from this unproductive situation and recover his capacity for reflective thought, at least for a while. The difficulty is compounded when the projection into the analyst leads to subtle or overt enactments that do not initially disturb the analyst but, on the contrary, constitute a comfortable collusive arrangement, in which the analyst feels his role is congruent with some internal phantasy. It may be difficult to recognise the defensive function this interaction serves for both the patient and the analyst and the more disturbing phantasies it defends against.
Calmodulin is a ubiquitous transducer of calcium signals in eukaryotes. In diploid plant species, several isoforms of calmodulin have been described. Here, we report on the isolation and characterization of calmodulin cDNAs corresponding to 10 genes from hexaploid (bread) wheat (Triticum aestivum). These genes encode three distinct calmodulin isoforms; one isoform is novel in that it lacks a conserved calcium binding site. Based on their nucleotide sequences, the 10 cDNAs were classified into four subfamilies. Using subfamily-specific DNA probes, calmodulin genes were identified and the chromosomal location of each subfamily was determined by Southern analysis of selected aneuploid lines. The data suggest that hexaploid wheat possesses at least 13 calmodulin-related genes. Subfamilies 1 and 2 were both localized to the short arms of homoeologous-group 3 chromosomes; subfamily 2 is located on all three homoeologous short arms (3AS, 3BS and 3DS), whereas subfamily 1 is located only on 3AS and 3BS but not on 3DS. Further analysis revealed that Aegilops tauschii, the presumed diploid donor of the D-genome of hexaploid wheat, lacks a subfamily-1 calmodulin gene homologue, whereas diploid species related to the progenitors of the A and B genomes do contain such genes. Subfamily 3 was localized to the short arm of homoeologous chromosomes 2A, 2B and 2D, and subfamily 4 was mapped to the proximal regions of 4AS, 4BL and 4DL. These findings suggest that the calmodulin genes within each subfamily in hexaploid wheat represent homoeoallelic loci. Furthermore, they also suggest that calmodulin genes diversified into subfamilies before speciation of Triticum and Aegilops diploid species.
OBJECTIVE: To compare an over-the-counter histamine2-receptor antagonist with an antacid as gastric acid reducers. DESIGN: Randomized, double-blind, placebo-controlled crossover trial. SETTING: Gastric secretory research laboratory in a Veterans Affairs medical center. PARTICIPANTS: Eighteen healthy volunteers (10 men and 8 women) aged 25 to 62 years with normal gastric acid secretion rates. INTERVENTIONS: The subjects received the histamine2-receptor antagonist famotidine (Pepcid AC, 10 mg), calcium carbonate antacid tablets (Tums, 1000 mg), or placebo medications 1 hour after a test meal. Two identical meals were taken 2.5 and 6.0 hours after the medication was given. MAIN OUTCOME MEASURES: Intragastric pH was maintained at 4.0 by in vivo intragastric titration with 0.3N sodium bicarbonate for 10 hours (1 hour before and 9 hours after medication). Reduction in sodium bicarbonate titrant use in the 2 treatment groups compared with titrant use with placebo was reflective of acid secretion inhibited by a famotidine or acid neutralized by calcium carbonate tablets. RESULTS: When evaluated in increments of 30 minutes, calcium carbonate had a rapid onset of action, neutralizing 6.7 mmol of acid in the first 30 minutes. However, its duration of effect was only 60 minutes. Famotidine had a delayed onset of action compared with antacid, beginning after 90 minutes. However, famotidine had a duration of effect of at least 540 minutes. At its peak effect, 210 minutes after administration, famotidine reduced acid secretion by 7.3 mmol per 30 minutes. CONCLUSIONS: Recommended over-the-counter doses of famotidine and calcium carbonate tablets have different pharmacokinetic profiles when taken in the postprandial period. The antacid has a rapid onset and short duration of action, while the histamine2-receptor antagonist has a delayed onset and a prolonged duration. Their peak potencies are similar.
METHODS: The effect of zinc supplementation on antipyrine clearance was evaluated in 14 outpatients with stable alcoholic liver disease, of whom nine had biopsy proven alcoholic cirrhosis. RESULTS: There was no change in antipyrine clearance after 14 days of zinc supplementation (median 12.5 vs 12.9 ml.min-1). However, a significant increase in P-prothrombin-proconvertin was found. There was a positive correlation between S-zinc and antipyrine clearance at inclusion (rs = 0.76) as well as after zinc supplementation (rs = 0.72). CONCLUSION: No effect of zinc supplementation on antipyrine clearance was found. The positive correlation between S-zinc and antipyrine clearance could be due to the confounding effect of alcoholic liver disease.
The acute human immunodeficiency virus type 1 (HIV-1) infection of activated peripheral blood mononuclear cells (PBMCs) from normal donors results in inhibition of cell proliferation and generation of functional suppressive T cells. Cultured HIV-1 infected PBMCs but not uninfected PBMCs, following irradiation, can inhibit the proliferation of antigen-activated autologous T cells in a dose-dependent way. CD8+ cell subpopulation is responsible for this inhibition. The presence of anti-alpha interferon (IFN alpha) and anti-Tat antibodies in the culture medium counteracts the HIV-1-induced immunosuppression and prevents the generation of suppressive T cells by these PBMCs. The reported data should have major implications for strategies of AIDS treatment which, in association with antiviral drugs, aim at targetting immune disorders.
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BACKGROUND: The role of gastric acid in the development of non-steroidal anti-inflammatory drug (NSAID)-induced gastric ulcers is unclear. The aim of this study was to determine the effect of the proton pump inhibitor omeprazole on the formation of indomethacin-induced gastric ulcers in a rabbit model. METHODS: Twenty-four rabbits were randomly divided into four groups and treated as follows: vehicle for indomethacin; vehicle for omeprazole; indomethacin (20 mg/kg b.d. subcutaneously for seven doses); and indomethacin plus omeprazole (both at 20 mg/kg b.d. subcutaneously for seven doses). On day 4 (after the seventh injection), rabbits were sacrificed, and gastric mucosal injury and prostaglandin formation were assessed. RESULTS: Subcutaneous administration of 20 mg/kg omeprazole b.d. caused a profound suppression of gastric acidity (i.e. pH above 5.0 continuously). This same dose of omeprazole significantly reduced gastric ulcer formation induced by indomethacin despite significant (> 80%) inhibition of gastric mucosal prostaglandin E2 (PGE2) formation. CONCLUSION: We conclude from these observations that gastric acid plays a critical role in the formation of indomethacin-induced gastric ulcers in rabbits.