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D Snead

Publications and source records attributed to D Snead.

At least 19 recordsLinked to original sources
PubMed2003

Glomus tumor as a cause of chronic low back pain: case report.

STUDY DESIGN: A case of chronic low back pain caused by a glomus tumor that persisted more than 30 years is presented. OBJECTIVE: To emphasize the need to consider skin tumors in the differential diagnosis of low back pain. SUMMARY OF BACKGROUND DATA: Chronic low back pain can be caused by a myriad of factors. There are six relatively common skin tumors, which present as painful lesions. As seen in the reported case, if they occur in the lumbar region, they can cause low back pain. METHODS: A subject with low back pain underwent an excision biopsy of a localized area of tenderness where his symptoms were reproduced when light pressure was applied. RESULTS: Histology confirmed that a glomus tumor accounted for the subject's pain. CONCLUSIONS: Painful skin tumors may cause low back pain and need to be considered in the differential diagnosis of chronic low back pain.

Chronic Disease↗
PubMed2002

Unusual sclerosing haemangiomas and sclerosing haemangioma-like lesions, and the value of TTF-1 in making the diagnosis.

AIMS: Sclerosing haemangiomas typically comprise a mixture of four architectural patterns (papillary, sclerotic, solid and haemorrhagic) and two cell types, eosinophilic cuboidal epithelial lining cells and sheets of rounded cells with either eosinophilic or clear cytoplasm. In most instances, recognition of these architectural and cytological features provides sufficient evidence for diagnosis. This study presents and discusses the histogenesis of four cases where difficulties in diagnosis were encountered, and reports the value of the antibody TTF-1 in making the diagnosis. METHODS AND RESULTS: Four cases with focal areas reminiscent of sclerosing haemangioma were reviewed and immunostained with an antibody panel including antibodies to TTF-1 and surfactant apoprotein A. Of these, one case was classified as sclerosing haemangioma combined with typical carcinoid, in which there was a mediastinal lymph node metastasis solely comprising the solid component of sclerosing haemangioma. The second was classified as an alveolar adenoma with sclerosing haemangioma-like areas. In the remaining two cases, diagnosis was confounded by presentation with predominantly cystic masses, the largest 70 mm in diameter. Immunohistochemically, TTF-1 was of greater value than surfactant apoprotein, in particular in identifying the solid component of sclerosing haemangioma when this was solely present. CONCLUSION: Sclerosing haemangiomas should be considered in the differential diagnosis of cystic pulmonary masses. They may also present histologically as combined tumours and metastasize to mediastinal nodes, indicating an, albeit low, malignant potential. TTF-1 is a valuable antibody in identifying the presence of a sclerosing haemangioma when typical features are absent.

Aged↗
PubMed2001

Isolated human papillomavirus 18-positive extragenital bowenoid papulosis and idiopathic CD4+ lymphocytopenia.

We report a case of isolated extragenital bowenoid papulosis (BP) in a young man with an idiopathic low CD4 count. The lesions occurred on the dorsal aspect of his left middle finger and were not associated with genital involvement. Polymerase chain reaction studies of a biopsy demonstrated human papillomavirus 18. As far as we are aware, this is the first documented case of BP (genital or extragenital) associated with idiopathic CD4 lymphocytopenia.

Adult↗
PubMed1997

Expression of human O6-methyl guanine methyl transferase (MGMT) in post replication repair (PRR) deficient CHO-UV-1 cells: compensation for hypersensitivity to methylating and ethylating agents but not to mitomycin C.

The cDNA for human MGMT was transfected into and expressed in CHO cells and the post-replication repair deficient mutant CHO-UV-1 cell, both of which are devoid of endogenous MGMT activity. Expression of MGMT activity was demonstrated by measurement of activity and by immunoblot analysis. The mutant phenotype of UV-1 is characterized by extreme hypersensitivity to killing by methylating and ethylating agents as well as the antitumor antibiotic mitomycin C (MMC). MGMT expression conferred equivalent, supra-normal levels of resistance to killing by MNNG (N-methyl-N'-nitro-nitrosoguanidine) or EMS (ethyl methanesulfonate) on CHO and UV-1, but had no effect on the lethality of MMC. So, even though a mutated gene other than MGMT is known to underlie the pleiotropic phenotype of UV-1, expression of MGMT compensates for part of this phenotype. This result indicates that attempts to concordance map and clone the gene(s) responsible for the UV-1 phenotype can be complicated when using MNNG selection due to compensation by the MGMT gene. These results also indicate that the post-replication repair deficient phenotype characterized in CHO-UV-1 cells, will be masked in cells normally expressing MGMT due to MGMT-mediated resistance to methylating and ethylating agents.

Alkylating Agents↗
PubMed1997

Primary repair without augmentation for early neglected Achilles tendon ruptures in the recreational athlete.

From 1987 to 1994, the senior author performed 41 Achilles tendon repairs. We identified 11 patients during this period (age, 35.3 years; range, 26-60 years) who fit the criterion for neglected Achilles tendon rupture (repair > or = 4 weeks and < or = 12 weeks from injury). All patients underwent proximal release of the gastrocsoleus complex, imbrication of the early fibrous scar without excision of any local tissue, and primary repair of the tendinous ends with two No. 5 Ticron sutures (5R, 6L). Several (three to five) No. 0 Vicryl sutures were used to augment the repair. The ankle was placed in a 20 degree plantarflexion nonweightbearing short leg cast for 3 weeks. All skin closures were primary. At 3 weeks, weightbearing as tolerated was initiated in a short leg cast. The cast was discontinued at 6 weeks, and physical therapy was initiated, consisting of range of motion exercises and closed kinetic exercises, progressing to functional exercises as swelling, strength, and pain allowed. Minimal follow-up was 18 months (mean, 3.5 years; range, 1.5-5.8 years). There have been no subsequent ruptures to date. All patients returned to a preinjury level of activity at a mean of 5.8 months (range, 2.5-9 months). Total range of motion was not different (P > 0.05) between the involved (67 degree) and uninvolved (74 degree) ankle. Plantarflexion loss of strength in the involved ankle was the same (98.4%, 88.1%, and 87.6% respectively, involved to uninvolved) as that seen after acute repair at all speeds tested. Visual analog pain scale (0 to 10) revealed a mean score of 0.7 (range 0-2) during activities of daily living and 1.0 (range, 0-3) during sports activity. The subjective and objective outcome was similar (P > 0.05) to that seen after an acute repair by the same surgeon. There were no complications including skin sloughs or nerve damage. We believe this is the first article to report the results after primary repair without augmentation for the neglected Achilles tendon rupture. We conclude that this approach can result in excellent clinical and functional outcome, a low rate of subsequent rupture, and a high rate of return to sports in the recreational athlete whose repair is performed between 4 and 12 weeks after injury.

Achilles Tendon↗
PubMed1995

A new immunohistochemical antibody for the assessment of estrogen receptor status on routine formalin-fixed tissue samples.

We describe a method for the immunocytochemical assessment of estrogen receptor (ER) status on routinely processed, formalin-fixed tissue using a recently developed commercially available monoclonal antibody (Dako 1D5) with a microwave antigen retrieval technique. A series of 90 cases of human breast carcinoma was analyzed and the staining was assessed using a semiquantitative microscopic scoring method and by assessment of the percentage of nuclei showing positive staining. The results were compared with assessment using another commercially available antibody (Abbott H222) and with clinical response to tamoxifen therapy. Direct comparison of the paired sets of H scores and the percentage of positively stained nuclei using the two different techniques showed a significant correlation. By assigning an arbitrary cut-off for positivity of H score = 50, assessment of ER status using DAKO 1D5 antibody was found to correlate with response to tamoxifen therapy with a sensitivity of 90% and a specificity of 51%, similar to values in previous studies using other methods. We conclude that assessment of ER status using this new antibody and technique gives accurate results on routinely processed, formalin-fixed tissue and may be used as an alternative to other methods.

Adult↗
PubMed1995

The use of a zinc based bioceramic as an osteoconductive agent in the rat model.

The many complications and risks of autograft and allograft bone have resulted in the search for an effective synthetic bone graft substitute [1,2]. The purpose of this study is to determine the effectiveness of ZCAP (zinc calcium phosphate) ceramic organic acid composite as an osteoconductive agent, including its possible benefits or risks for patients requiring bone grafting. A solid control model has been developed with an isolated mid-diaphyseal femur fracture immobilized by intramedullary threaded K-wire fixation. Two trials were performed in which two formulations of ZCAP composite ceramic were tested. The first, used in eighteen rats will be referred to as ZCAP1, the second, used in six rats will be referred to as ZCAP2. In the first trial rat femurs were augmented with 0.1 g ZCAP1 composite ceramic which varied in pore size. One pore size performed better than the others, so that pore size along with some minor changes in the composite design to increase resistance to the stresses inherent in our weight bearing model resulted in ZCAP2, which was tested in the second trial. The rats were sacrificed at ten weeks, during which time all rats remained viable. Blood work was done prior to sacrifice and radiography was done on all femurs. After sacrifice, gross morphological exam showed filling of the defect. Sections of the femurs from each group were analyzed by decalcified histological examination, electron microscopy, and tensile strength testing. The ZCAP composite ceramic had no significant effect on blood chemistry or body weight. Initial histological studies were consistent with endochondral ossification which was confirmed by electron microscopy.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Primary breast lymphoma with skin involvement arising in lymphocytic lobulitis.

Primary breast lymphoma is a rare tumour which has recently been associated with pre-existing lymphocytic lobulitis. We report a patient with lymphocytic lobulitis in whom the lymphoma recurred in the contra-lateral breast 5 years after the initial presentation, to be followed shortly afterwards by skin involvement. This progression illustrates the relationship between extra-nodal lymphomas and underlying autoimmune disease and the homing of lymphomas to related sites.

Breast Neoplasms↗
PubMed1992

Exercise training at and above the lactate threshold in previously untrained women.

We examined the effects of training at and above the lactate threshold in previously untrained women. Twenty-four untrained eumenorrheic women (age = 31.3 +/- 4.0 yrs, wt = 66.2 +/- 7.6 kg, ht = 166.4 +/- 5.8 cm) were assessed at baseline [during days 1-3 of the menstrual cycle (MC)] and every 4 MC after that (for 1 year) for VO2 and velocity (V) at LT, fixed blood lactate concentrations (FBLC) of 2.0, 2.5, and 4.0 mM, and Max. Subjects were assigned to control (C, n = 7), at LT/LT, trained 6 days/week at the velocity associated with LT, (n = 9) or above LT (greater than LT, trained 3 days/week at the velocity midway between V LT and V Max and 3 days/week at V LT, n = 8) groups. Exercise prescriptions were adjusted after each assessment and each group progressed similarly in weekly mileage. No between group differences were observed before training. After training the greater than LT group had significantly higher values than the C and /LT groups for LT (p less than 0.05). For FBLC of 2.0, 2.5, and 4.0 mM and Max, the greater than LT group values were greater than the C group (p less than 0.05). No differences were observed after training between the /LT and C groups. Although the greater than LT group had higher VO2 and V Max values than the /LT group after training, these differences were not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Perceptual responses and blood lactate concentration: effect of training state.

The present study investigated the effect of training state on ratings of perceived exertion obtained at the lactate threshold (LT) and fixed blood lactate concentrations (FBLC) of 2.0, 2.5, and 4.0 mM. Runners (N = 20) and nonrunners (N = 29) completed a progressive horizontal treadmill (TM) running test which allowed identification of the TM velocities associated with the LT and FBLC. Runners attained significantly higher TM velocities, greater VO2, greater VE, greater heart rate, and a lower ventilatory equivalent for oxygen (VE/VO2) at each exercise intensity, with the exceptions of heart rate at 4.0 mM and VE/VO2 at the LT. Compared to nonrunners, runners also attained higher VO2, VE, and heart rate relative to peak values at LT and 2.0, 2.5, and 4.0 mM. Despite these relative and absolute physiological differences, there were no differences between groups in local, central, or overall ratings of perceived exertion (RPE) (Borg scale) at any condition. The data from both groups were combined to give the following means and SD for overall RPE during horizontal running: at the LT-11.0 +/- 2.0, and at FBLC of 2.0 mM-13.7 +/- 2.1, 2.5 mM-14.5 +/- 1.8, and 4.0 mM-16.5 +/- 2.3.

Adult↗
PubMed1991

Effect of exercise modality on ratings of perceived exertion at various lactate concentrations.

The effect of exercise modality on the relationship between ratings of perceived exertion (RPE), blood lactate concentration, oxygen uptake (VO2), and heart rate (HR) was examined in 29 untrained male subjects who completed counterbalanced VO2max/lactate threshold (LT) protocols on a cycle ergometer (CE) and treadmill (TM). Heart rate, VO2, and RPE were determined at power outputs corresponding to LT and fixed blood lactate concentrations (FBLC) of 2.0, 2.5, and 4.0 mM and during maximal exercise. A repeated measures ANOVA indicated that, despite significant differences across exercise modality in HR and VO2 at LT, FBLC, and maximal exercise, no significant differences in RPE were found between exercise modalities during leg exercise. Mean (+/- SD) respective values for overall RPE at LT and FBLC of 2.0 mM, 2.5 mM, 4.0 mM, and max were 10.2 (2.2), 13.1 (2.1), 14.1 (2.3), 15.9 (2.3), and 18.8 (1.3) for the CE and 10.8 (1.9), 13.8 (1.8), 14.6 (1.6), 16.2 (2.6), and 18.5 (1.5) for the TM. It was concluded that exercise modality does not affect the perception of exertion at LT, FBLC, or maximal exercise and that a strong relationship exists between RPE and blood lactate concentrations.

Adult↗
PubMed1990

Reliability and validity of a continuous incremental treadmill protocol for the determination of lactate threshold, fixed blood lactate concentrations, and VO2max.

Fifteen male runners were tested on two occasions to determine the reliability of a continuous incremental level running treadmill protocol (C), with 3-min stages, for lactate threshold (LT) and fixed blood lactate concentration (FBLC) (2.0 mM, 2.5 mM, 4.0 mM) assessment. Test-retest (T-RT) reliability coefficients for velocity at LT, 2.0 mM, 2.5 mM, and 4.0 mM were r = 0.89, 0.91, 0.95, and 0.95, respectively (velocity ranged from 215.3 m/min at LT to 273.6 m/min at 4.0 mM). Mean differences in T-RT velocity values ranged from 0.7 m/min (at LT) to 6.0 m/min (at 2.5 mM; 252.3 m/min vs 258.3 m/min; NS) and the standard errors of measurement were less than +/- 10.0 m/min. Similar results were observed for VO2, with T-RT r values ranging from r = 0.82 (at LT) to r = 0.88 (at 2.0 mM) (VO2 ranged from 47.2 ml/kg.min-1 at LT to 60.9 ml/kg.min-1 at 4.0 mM; VO2 peak = 65.6 ml/kg.min-1). Mean differences in T-RT VO2 values were less than 1.4 ml/kg.min-1 (NS) and the standard errors of measurement were less than +/- 2.95 ml/kg.min-1. Interinvestigator and intrainvestigator reliability coefficients were high and ranged from r = 0.91 to r = 0.99. Validity of C was assessed in an additional 16 male runners who completed C and a criterion discontinuous (D) protocol (using a series of 10-min stages) for LT and FBLC assessment. Results indicated that C and D resulted in similar VO2 and velocity values at LT and FBLC.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Percentages of maximal heart rate, heart rate reserve and VO2max for determining endurance training intensity in male runners.

The use of 60%-95% of maximal heart rate (HR), heart rate reserve (HRR) and VO2max as exercise training intensities was examined in male runners, and these intensities were related to VO2 observed at the lactate threshold (LT) and fixed blood lactate concentrations (FBLC) of 2.0, 2.5, and 4.0 mM. Thirty-one subjects (means age = 29.9 +/- 9.1 yrs; means ht = 177.3 +/- 8.2 cm; means wt = 69.2 +/- 9.9 kg) completed a level running treadmill protocol. The mean values at LT, FBLC of 2.0, 2.5, 4.0 mM and max for VO2 were 52.7, 56.4, 58.0, 61.2 and 63.5 ml/kg.min -1, respectively: for velocity they were 237.4, 252.2, 260.6, 274.4 and 286.5 m/min, respectively; and for HR were 165.7, 172.7, 176.5, 182.3 and 187.4 bts/min, respectively. The majority of subjects were not above LT (N = 20), until an intensity of 90% HR max was attained. At 95% HR max the majority of subjects were above 2.0 mM (N = 23) and 2.5 mM (N = 17) but below 4.0 mM (N = 26). For HRR, 85% HRR was necessary for the majority of subjects to be above LT (N = 20), 90% HRR resulted in the majority of subjects being above 2.0 mM (N = 19), while 95% HRR was required for the majority of subjects to be above 2.5 mM (N = 23). At 95% HRR 14 subjects were above 4.0 mM. For % VO2max, the intensities required for the majority of subjects to be above LT, FBLC of 2.0, and 2.5 mM were 90%, 95% and 95% VO2max, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Effects of training specificity on the lactate threshold and VO2 peak.

We examined the effects of training specificity on the lactate threshold (LT) and VO2peak. Sixteen male subjects completed VO2peak/LT protocols on the cycle ergometer (CE) and treadmill (TM) before and after a training program. The subjects were assigned to run training (N = 5), cycle training (N = 6), and control groups (N = 5). Subjects trained 4 day/week for 10 weeks at approximately 89% of pre-training VO2peak. Results indicated that run training increased VO2 at LT (VO2LT) within both the CE and TM protocols (17.9 to 22.5 ml/kg.min-1 for CE, 22.7 to 36.0 ml/kg.min-1 for TM, p less than 0.05) with the 58.5% increase in VO2LT for TM being greater than the 30.3% increase for CE (p less than 0.05). Cycle training resulted in a 38.7% increase in CE VO2LT (19.7 to 27.4 ml/kg.min-1, p less than 0.05) with no significant improvement in TM VO2LT (23.6 to 24.0 ml/kg.min-1). Similar increases in VO2peak were observed for CE and TM protocols for both cycle and run training groups (VO2peak increased by 11.9 to 20.7% in both CE and TM regardless of training mode). No changes were observed in the control group for any variable. The present data suggest that increases in LT resulting from training may be specific to the mode of exercise.

Adult↗
PubMed1990

Prediction of lactate threshold (LT) and fixed blood lactate concentrations (FBLC) from 3200-m running performance in women.

The present study evaluated the accuracy of predicting velocity and oxygen consumption (VO2) at the LT lactate threshold and FBLC fixed blood lactate concentrations from a 3200-m time trial in women. Forty-four women (mean age = 31.1 yrs, mean ht = 164.9 cm, mean wt = 65.0 kg) completed a treadmill protocol for the determination of LT and FBLC and a 3200-m time trial. Velocity and VO2 values at LT, FBLC of 2.0 2.5, and 4.0 mM, and peak were determined. Mean VO2 and velocity ranged from 27.8 +/- 10.8 ml/kg.min-1 at LT to 42.5 ml/kg.min-1 at peak and from 129.8 +/- 44.0 m.min-1 at LT to 187.0 +/- 52.4 m.min-1 at peak, respectively. Results indicated that a 3200-m time trial (mean time = 20.6 +/- 6.6 min) was a good predictor of VO2 and velocity at LT, FBLC, and peak. Correlation coefficients (using a quadratic model) for velocity ranged from R = 0.96 to R = 0.98 with SEE ranging from 9.0 to 13.1 m.min-1. Correlation coefficients for VO2 ranged from R = 0.94 to R = 0.96 with SEE ranging from 2.8 to 3.6 ml/kg.min. The validity of these regression equations was examined in 13 women who completed a 12-month running program (VO2 LT, VO2 at FBLC of 2.0, 2.5 and 4.0 mM, and VO2 peak increased by 34.7, 19.9, 16.9, 11.9, and 5.4%, respectively, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗