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Biomedical subjects

D M Jones

Publications and source records attributed to D M Jones.

At least 37 records · Page 2Linked to original sources
PubMed1999

Can ploidy of prostate carcinoma diagnosed on needle biopsy predict radical prostatectomy stage and grade?

PURPOSE: Deoxyribonucleic acid ploidy correlates with the biological behavior of prostate carcinoma. However, the usefulness of ploidy on needle biopsies that show prostate cancer has not been established to our knowledge. MATERIALS AND METHODS: We retrospectively determined ploidy on needle biopsies of 159 men with prostate carcinoma treated surgically at Johns Hopkins Hospital. Ploidy was determined by image analysis of Feulgen stained slides. Needle ploidy and Gleason score were compared as prognostic tools in the prediction of grade and stage of subsequent prostatectomy. RESULTS: Of the 159 cases 98 (62%) were diploid, 16 (10%) tetraploid and 45 (28%) aneuploid. Of the diploid, tetraploid and aneuploid tumors 69, 50 and 44%, respectively, proved to be organ confined. Tetraploid and aneuploid tumors were grouped for the remaining analysis. Needle ploidy correlated significantly with pathological stage (p = 0.003). However, needle Gleason score correlated even more strongly (p <0.001), and on multivariate analysis ploidy was not further predictive of pathological stage once Gleason score was considered. Needle ploidy and Gleason score were predictive of prostatectomy Gleason score (6 or less versus 7 or greater), and on multivariate analysis ploidy was an independently significant predictor of this parameter (p = 0.04). In 13 cases (8%) there was an important grading discrepancy, in which needle ploidy would have accurately predicted prostatectomy grade. However, in 33 cases (21%) needle and prostatectomy Gleason scores were congruent, and needle ploidy did not accurately predict prostatectomy Gleason score. CONCLUSIONS: With accurate needle Gleason grading, ploidy is not helpful in predicting prostatectomy findings. However, ploidy correlates with prostatectomy stage and grade, and may be useful if accurate Gleason grading is a concern.

Aged↗
PubMed1999

Effect of the type carrier used on the results of dichlorodifluoromethane application to teeth.

Thermal testing, especially cold, is an important part of diagnosing pulpal vitality. It was the purpose of this study to determine (i) if a difference exists in temperature when Endo ice is used with four different applicators, and (ii) if there is one applicator device that provides the greatest thermal change for a tooth. Endo ice was used with the following applicators: a #2 standard size large cotton pellet, a #4 standard size small cotton pellet, a wood stick cotton tip applicator, and a cotton roll. The temperature of a mandibular incisor pulp chamber was measured in degree C 10 s after the application of the dichlorodifluoromethane (DDM) to the midfacial surface of the crown. Also, the DDM was applied to each applicator either by direct spray or by submergence in DDM liquid. This study found that the greatest temperature change was recorded by Endo Ice (DDM) sprayed directly onto a large cotton pellet. There was no significant difference between directly spraying or submerging the applicator in DDM liquid.

Aerosols↗
PubMed1999

Salivary antibodies following parenteral immunization of infants with a meningococcal serogroup A and C conjugated vaccine.

Bacterial and viral salivary antibody testing is proving sensitive and specific, useful for epidemiological studies, and is simple and non-invasive. Salivary serogroup C polysaccharide-specific (SC PS-S) IgA and IgG were determined as a proportion of total salivary IgA and IgG in a group of UK infants who were recipients of a conjugated A/C meningococcal PS vaccine. Geometric mean concentrations (GMCs) of salivary SC PS-S IgG per mg of total IgG (microg/mg) were 0.1 pre-vaccination, rising to 8.2 post first, 16.1 post second and 29.3 post third dose of vaccine. For IgA, the corresponding GMCs in ng/mg were 0.1, 82.8, 69.6 and 91.2. Significant correlations (P < 0.0001) were found between serum Ig and salivary IgG SC PS-S antibody for pre-vaccine and 1 month post each dose of vaccine suggesting that SC PS-S IgG in saliva was largely derived from serum. Of the five infants whose sera were analysed for isotype-specific responses, only traces of IgM and IgA were measurable suggesting that the SC PS-S IgA was locally produced. These findings suggests that the widespread use of meningococcal conjugate vaccines is likely to reduce nasopharyngeal carriage and may thereby induce herd immunity in the vaccinated population.

Antibodies, Bacterial↗
PubMed1999

Change of intensity fails to produce an irrelevant sound effect: implications for the representation of unattended sound.

Sequences of changing sounds that are irrelevant to the task at hand disrupt serial recall appreciably even though participants are instructed to ignore the sounds. Three experiments, which compared the effect of changing token identity with that of changing intensity in the 55- to 85-dB (A) range, were conducted. Although serial recall was impaired by changes in token identity, no disruptive effects of a change in intensity were found. This was replicated using speech and nonspeech. Overall, the absence of a changing intensity effect was based on an analysis of the performance of 115 participants in a design whose power was .98. This outcome suggests that the representation of intensity in preattentive processing of auditory stimuli is somewhat different from that of other acoustic features.

Humans↗
PubMed1999

Cerebral edema and priapism in an adolescent with acute lymphoblastic leukemia.

Priapism and increased intracranial pressure are both rare, but recognized, manifestations of leukemia. However, they have never been reported in the same patient. We report a 15-year-old male with acute lymphoblastic leukemia who presented with hyperleukocytosis, priapism, and increased intracranial pressure. Central nervous system leukostasis and cerebral edema may have been detected earlier, had his history of priapism been known. Management of hyperleukocytosis complicated by priapism and increased intracranial pressure is discussed.

Adolescent↗
PubMed1999

Analysis of the adult thymus in reconstitution of T lymphocytes in HIV-1 infection.

A key question in understanding the status of the immune system in HIV-1 infection is whether the adult thymus contributes to reconstitution of peripheral T lymphocytes. We analyzed the thymus in adult patients who died of HIV-1 infection. In addition, we studied the clinical course of HIV-1 infection in three patients thymectomized for myasthenia gravis and determined the effect of antiretroviral therapy on CD4(+) T cells. We found that five of seven patients had thymus tissue at autopsy and that all thymuses identified had inflammatory infiltrates surrounding lymphodepleted thymic epithelium. Two of seven patients also had areas of thymopoiesis; one of these patients had peripheral blood CD4(+) T-cell levels of <50/mm3 for 51 months prior to death. Of three thymectomized patients, one rapidly progressed to AIDS, one progressed to AIDS over seven years (normal progressor), whereas the third remains asymptomatic at least seven years after seroconversion. Both latter patients had rises in peripheral blood CD4(+) T cells after antiretroviral therapy. Most patients who died of complications of HIV-1 infection did not have functional thymus tissue, and when present, thymopoiesis did not prevent prolonged lymphopenia. Thymectomy before HIV-1 infection did not preclude either peripheral CD4(+) T-cell rises or clinical responses after antiretroviral therapy.

Adolescent↗
PubMed1999

The diagnosis of the os trigonum syndrome with a fluoroscopically controlled injection of local anesthetic.

PURPOSE: To report the results of excision of the os trigonum using a fluoroscopically controlled injection of local anesthetic to diagnose the os trigonum syndrome. DESIGN AND PATIENTS: Os trigonum syndrome is a recognized cause of pain in the posterior aspect of the foot and ankle. The symptoms and physical findings, however, are often nonspecific and difficult to differentiate from other causes of posterior ankle pain. We report four patients with persistent posterolateral ankle pain despite prolonged nonoperative treatment. An os trigonal syndrome was diagnosed by a positive response to a fluoroscopically guided local anesthetic injection in the region of synchondrosis between the os trigonum and the posterior talus. RESULTS: All four patients underwent excision of the os trigonum with complete resolution of symptoms and return to full activity. CONCLUSIONS: Fluoroscopically controlled injection can help confirm the suspected diagnosis of an os trigonum syndrome and may have positive predictive value regarding the outcome of excisional surgery.

Adolescent↗
PubMed1998

Immunologic characterization of CD7-deficient mice.

Human CD7 is an Ig superfamily molecule that is expressed on mature T and NK lymphocytes. Although in vitro studies have suggested a role for CD7 in lymphoid development and function, the exact function of CD7 in vivo has remained elusive. One patient has been reported with SCID syndrome attributed to CD7 deficiency. To study in vivo functions of CD7, we have generated CD7-deficient mice and assessed their lymphoid development and function. CD7-deficient mice were viable, had normal peripheral blood and spleen lymphocyte numbers, and had normal specific Ab responses with Ag-driven Ig isotype switching. Thymocyte numbers were normal in 4-wk-old, 6-mo-old, and 1-yr-old CD7-deficient mice, but in 3-mo-old CD7-deficient mice, total thymocyte numbers were significantly increased by 60% (p < 0.02) compared with normal age-matched +/+ littermates. CD7-deficient splenocytes proliferated normally in response to various mitogens, including PHA, anti-CD3, Con A, and LPS. While NK cell numbers and cytolytic activity to YAC targets were normal, CD7-deficient mice had lower Ag-induced MHC class I-restricted CTL activity against OVA-transfected target cells than did +/+ control mice. Thus, CD7-deficient mice did not have a SCID syndrome, but rather had transient increases in thymocyte numbers at age 3 mo and altered splenocyte Ag-specific CTL effecter cell activity. These data suggest a role for CD7 in regulating intrathymic T cell development and in mediating CTL effecter function.

Animals↗
PubMed1998

Molecular variation of meningococcal serotype 4 antigen genes.

Changes in the frequency of serogroup B non serotypable (B:NT) meningococci isolated in England and Wales were investigated by T-track fingerprint analysis, DNA nucleotide sequence determination, and serotyping by whole cell ELISA and dot blot assay. Seventy-three per cent of the isolates designated as B:NT by the Meningococcal Reference Unit (MRU) dot blot assay during 1993-4, expressed variants of the serotyping antigen, PorB, that were serotype 4 by whole cell ELISA. T-track fingerprint patterns of these and other 'serotype 4' isolates revealed five distinct porB alleles which were shown by nucleotide sequence determination to encode different peptide sequences. Differential binding of the 'serotype 4' mAbs MN14G21 and 5DC4C8G8 in whole cell ELISA and dot blot assays was the result, (i) of differences in the peptide sequence of predicted surface loop I and (ii) an amino acid deletion in predicted loop VI of the PorB protein.

Amino Acid Sequence↗
PubMed1998

Irrelevant sound disrupts order information in free recall as in serial recall.

The claim that the sensitivity of free recall to disruption by irrelevant sound is a function of the extent to which rote rehearsal is employed as a mnemonic strategy was investigated in two experiments. The degree of disruption by irrelevant sound in terms of both item and order information was contrasted under serial and free recall instructions. Irrelevant sound was found to disrupt order and item information equally in serial and free recall tasks (Experiment 1). Contrary to previous reports, an effect of irrelevant sound was also demonstrated on free recall of particularly long lists, and the interaction between list length and retention interval in the irrelevant sound effect was examined (Experiment 2). Generally, the results support the view that irrelevant sound disrupts the use of order cues.

Acoustic Stimulation↗
PubMed1998

Effectiveness and patient satisfaction with nurse-directed treatment of Barrett's esophagus.

OBJECTIVE: Using clinical practice guidelines, a registered nurse adjusted antireflux medications, evaluated esophageal biopsy reports, determined the interval between surveillance endoscopies, and provided education for patients with Barrett's esophagus. No previous reports have assessed the effectiveness or patient satisfaction associated with registered nurse-provided primary care. Because estimates of the incidence of dysplasia and adenocarcinoma vary widely, we also prospectively followed a cohort of patients with Barrett's esophagus. METHODS: Charts were reviewed to determine the frequency of variation from guidelines, the annual incidence of dysplasia and adenocarcinoma, and frequency of reflux symptoms. Patients were mailed a questionnaire to assess satisfaction with their medical care and with the nurse. RESULTS: Variation by the nurse from the guidelines on surveillance endoscopy (1.9%) and the treatment of reflux (1.3%) was rare. Most patients were very satisfied (score of 6 on 0-6-point Likert scale) with overall medical care (88%), and patient education (76%), and most patients did not think that increased physician involvement would improve their care (93%). Ninety-seven percent of patients had control of reflux symptoms. Two patients with long segment Barrett's esophagus (n = 67) developed high grade dysplasia over 323 patient-yr of follow-up (1 of 162 patient-yr for an annual incidence of 0.6%). No patients with short segment Barrett's esophagus (n = 56) developed high grade dysplasia or adenocarcinoma over 172 patient-years of follow-up. CONCLUSION: The registered nurse in our clinical setting effectively administered clinical practice guidelines for the management of Barrett's esophagus without clinically significant morbidity or patient dissatisfaction. Before these results can be generalized to other settings, further studies will need to be performed.

Adenocarcinoma↗
PubMed1998

Associations between heat-stable (O) and heat-labile (HL) serogroup antigens of Campylobacter jejuni: evidence for interstrain relationships within three O/HL serovars.

A comparative examination of the heat-stable (O) and heat-labile (HL) serogrouping results for 9,024 sporadic human isolates of Campylobacter jejuni revealed conserved associations between specific O and HL antigens (O/HL serovars). Forty-nine percent of the isolates which grouped for both O and HL antigens belonged to one of three serovars: O 4 complex/HL 1 (17.9%), O 1/HL 2 (16.8%), or O 50/HL 7 (14.5%). Other common serovars were O 2/HL 4 (8.3%), O 6/HL 6 (8.1%), O 53/HL 11 (4.5%), O 19/HL 17 (3.3%), O 5/HL 9 (3.3%), O 9/HL 9 (3.2%), and O 23/HL 5 (3.1%). These 10 serovars accounted for 83.1% of the serogroupable isolates. A large number of strains (41.3%) could be typed by only one of the two methods or could not be serogrouped (11%). Strains belonging to three serovars, O 2/HL 4, O 50/HL 7, and O 23/HL 5, were further characterized by combining data from expressed features (O/HL serogroups, phage groups, and biotypes) with restriction fragment length polymorphism genotypes. These polyphasic data demonstrated that within each serovar, individual isolates showed substantial conservation of both genomic and phenotypic characteristics. The essentially clonal nature of the three serovars confirmed the potential of combined O and HL serogrouping as a practical and phylogenetically valid method for investigating the epidemiology of sporadic C. jejuni infection.

Animals↗
PubMed1998

Combination chemotherapy for metastatic or locally advanced genitourinary squamous cell carcinoma: a phase II study of methotrexate, cisplatin and bleomycin.

PURPOSE: The prognosis of patients with advanced squamous cell carcinoma of genitourinary origin is poor. While single agent chemotherapy results mainly in partial responses of short duration, data on the efficacy of combination chemotherapy are extremely limited. We determined the response rate and toxicity of a combination of 3 of the most active agents, methotrexate, cisplatin and bleomycin, in patients with advanced genitourinary squamous cell carcinoma. MATERIALS AND METHODS: Patients with metastatic or locally advanced genitourinary squamous cell carcinoma were eligible for study. Treatment consisted of 200 mg./m.2 methotrexate on days 1, 15 and 22, and 20 mg./m.2 cisplatin and 10 mg./m.2 bleomycin on days 2 through 6 during a 28-day cycle. RESULTS: Of the 30 patients who enrolled in the trial 29 were evaluable for response. Objective response was achieved in 16 patients (55%, 95% confidence interval 36 to 72), 4 of whom achieved a complete response (14%). Median objective response duration was 4.7 months (range 1.9 to 39.5). Median survival of the entire group was 11.5 months (range 1.5 to 87.0). Of the patients 9 achieved disease-free status, including 6 following consolidation surgery or radiation therapy. Median survival of these 9 patients (34.4 months, range 9.6 to 87.0) was significantly greater (p = 0.0003) than that of patients who did not become disease-free (7.0 months, range 1.5 to 38.6). Grade III or IV hematological toxicity in 116 courses included neutropenia (13%) and thrombocytopenia (6%). Among 30 patients evaluable for toxicity serious nonhematological toxic effects included stomatitis (3%) and renal toxicity (7%). There was 1 death from neutropenic sepsis. CONCLUSIONS: Methotrexate, cisplatin and bleomycin combination chemotherapy for genitourinary squamous cell carcinoma results in a high but short lived overall response rate, and a low complete response rate with manageable toxicity. A multidisciplinary approach to achieve disease-free status may provide the best opportunity to effect survival and should be the focus of future trials.

Adult↗
PubMed1997

Non-culture diagnosis and serogroup determination of meningococcal B and C infection by a sialyltransferase (siaD) PCR ELISA.

Rapid, non-culture, serogroup determination of meningococcal infection is important in contact management where vaccination may be possible. The impending availability of polysaccharide-protein conjugate vaccines for serogroup C disease requires maximal case ascertainment, with serogroup determination, at a time when the number of culture confirmed meningococcal infections is decreasing. A polymerase chain reaction assay (PCR), based on a restriction fragment length polymorphism (RFLP) in the meningococcal serogroup B and C sialytransferase (siaD) gene, was developed to combine the non-culture diagnosis of meningococcal infection from CSF, whole blood and serum with serogroup (B and C) identification. The PCR assay was adapted to an ELISA format incorporating hybridization with serogroup-specific B and C oligonucleotide probes. Specificity for CSFs was 100% and sensitivities were respectively 81, 63 and 30% for CSFs, whole blood and sera. The serogroup-specific PCR ELISA is a significant addition to currently available tests for non-culture diagnosis of meningococcal infection and outbreak investigation.

Base Sequence↗
PubMed1997

Genotype analysis of human blood isolates of Campylobacter jejuni in England and Wales.

Genomic profiles were obtained for 76 strains of Campylobacter jejuni isolated from bacteraemic patients in England and Wales over the period 1981-94. Genotyping was performed by restriction fragment length polymorphism (RFLP) analysis using a random cloned DNA probe, and by ribotyping with a PCR-generated C. jejuni 16S ribosomal DNA probe. Phenotypic characterization was achieved by heat-stable (HS) and heat-labile (HL) serogrouping, and Preston phagetyping and biotyping. The blood isolates were genomically heterogenous, with 24 RFLP/16S profiles occurring within the 76 strains. Forty-four percent of isolates belonged to one of three RFLP/16S genotypes, reflecting the patterns seen in faecal isolates, except that genotypes usually associated with the HS 1 antigen were uncommon. The two most prevalent genotypes, characteristic of HS 2 and HS 4 strains, showed similarity by cluster analysis. Further evidence was seen of associations between phenotypic and genotypic characters within some HS serogroups. Chromosomal profiling by RFLP analysis does not indicate that particular genotypes have a predisposition to invade the bloodstream.

Bacteremia↗
PubMed1997

Disruption of short-term recognition memory for tones: streaming or interference?

A sequence of auditory stimuli interpolated between the initial presentation of a tone and a comparison tone impairs recognition performance. Notably, the impairment is much less with interpolated speech than with tones. Six experiments converge on the conclusion that this pattern of impairment is due more to the organization of the interpolated sequence than to its similarity to the to-be-remembered standard. Factors that contribute to the coherence of the interpolated sequence into a stream distinct from the initial tone are primary determinants of the level of impairment. This is demonstrated by manipulating factors that contribute to the coherence of the interpolated sequence by the action of temporal, spatial, timbral, and tonal attributes. However, the relative immunity of recognition performance to the interpolation of unprocessed digit sequences is not explained wholly by such coherence.

Auditory Perception↗