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T Shook

Publications and source records attributed to T Shook.

9 recordsLinked to original sources
PubMed2002

Cobe Spectra is superior to Fenwal CS 3000 Plus for collection of hematopoietic stem cells.

One hundred and seventy-seven stem cell apheresis procedures performed on 91 patients using the Fenwal CS 3000 Plus cell separator and 61 procedures performed on 37 patients using the Cobe Spectra cell separator were studied to compare the CD34(+) cell collection efficiencies (CE; the proportion of the total CD34(+) cell content in the blood volumes processed that is harvested) of the two machines. The absolute peripheral blood CD34(+) cell count was comparable for the two groups (P = 0.27). A strong correlation was seen between the blood CD34(+) cell count and the total number of CD34(+) cells collected for the Spectra (r(2) = 0.59; P < 10(-6)) and for the CS 3000 Plus (r(2) = 0.60; P < 10(-6)). No significant correlation emerged between the peripheral blood CD34(+) cell count and the CE of either machine. The total number of CD34(+) cells collected per procedure was comparable (P = 0.51): median 113 x 10(6) for CS 3000 Plus and median 218 x 10(6)for Spectra. CE was significantly higher with the Spectra (median 45.7%, range 9.8-98.6%) than the CS 3000 Plus (median 30.3%, range 1.7-89.3%; P < 0.00001). We conclude that the CD34(+) cell CE of the Spectra is superior to that of the CS 3000 Plus. Therefore, under the usual clinical conditions, Cobe Spectra should be used preferentially for peripheral blood progentor cell collection to maximize the number of hematopoietic stem cells collected.

Blood Cell Count↗
PubMed2001

CD34(+) cell collection efficiency does not correlate with the pre-leukapheresis hematocrit.

One hundred and seventy-seven large-volume leukapheresis procedures performed on 91 patients over a 15 month period were reviewed to see if the pre-apheresis hematocrit (Hct) affected the CD34(+) cell collection efficiency (CE) of the Fenwal CS 3000 Plus cell separator. The Hct was 0.174-0.461 (median 0.317), and the peripheral blood CD34(+) cell count 2-2487 per microl (median 21). The total CD34(+) cell quantity collected was 3.0-2677.2 x 10(6) (median 113.0). Based on the number of CD34(+)cells contained in the blood volume processed (23.3-37303.2 x 10(6); median 318.0), the CE was 1.7-87.5% (median 30.3). No correlation was found between the Hct and CE (r(2) = 0.0034; P = 0.44) or the total CD34(+) cell quantity collected (r2 = 0.0040; P = 0.40). CEs for Hct <0.25 (median CE 36%), Hct 0.25-0.299 (median CE 30%) and Hct 0.30 (median CE 30%) were comparable. As expected, highly significant correlations were seen between the CD34(+) cell quantities collected and quantities processed (r2 = 0.59; P < 10(-6)) as well as the peripheral blood CD34(+) cell counts (r2= 0.60; P < 10(-6)). We conclude that the minimum acceptable Hct or hemoglobin level for leukapheresis should be dictated by clinical circumstances because it does not affect stem cell collection.

Antigens, CD34↗
PubMed2001

Evidence for stunned myocardium in humans: a 2001 update.

This article describes clinical situations in which stunning occurs and updates previous reviews on the topic. Stunning following angioplasty, angina and exercise-induced ischemia, infarction, and after cardiac surgery are described. In addition, newer concepts regarding stunning, including neurogenic stunned myocardium, are discussed. Left atrial stunning following cardioversion is a recently recognized phenomenon with important clinical implications, but differs from the original concept of post-ischemic stunning.

Angina, Unstable↗
PubMed1998

Prospective temporal analysis of the onset of preinfarction angina versus outcome: an ancillary study in TIMI-9B.

BACKGROUND: The timing of onset of angina before myocardial infarction in relation to outcome is unknown. METHODS AND RESULTS: We prospectively determined the importance of the time of onset of preinfarction angina in relation to 30-day outcomes in the TIMI-9B study from standardized forms. Of the 3002 patients entered into the study, 425 reported angina before their myocardial infarction. Patients with angina onset within 24 hours of infarction had a lower 30-day cardiac event rate (mortality, recurrent myocardial infarction, heart failure, or shock) at 4% than those with onset of angina >24 hours (17%; P=.030). A history of any angina alone was not associated with reduced event rate. Peak creatine kinase levels tended to be lower in the group with angina within 24 hours. These benefits were not due to higher rates of use of antianginal medicines or aspirin and were not a consequence of differences in baseline characteristics or disease states (hypertension, hypercholesterolemia) among subgroups. CONCLUSIONS: These temporal observations are consistent with the concept of preconditioning by preinfarction angina but do not rule out other mechanisms.

Aged↗
PubMed1998

Protection Conferred by Preinfarct Angina is Manifest in the Aged Heart: Evidence from the TIMI 4 Trial.

There has been debate regarding the issue of whether ischemic preconditioning is effective in the aging and diseased heart. Therefore, we retrospectively analyzed the effect of preinfarction angina in patients less than versus greater than 60 years of age in the TIMI 4 study. Preinfarction angina was defined as an episode of typical angina pectoris that occurs prior to the time of index chest pain associated with the myocardial infarction itself. Patients who were 60 years and older had a higher rate of death and the combined endpoints of death, heart failure/shock, and/or reinfarction compared with younger patients. However, patients 60 years or older who had preinfarction angina had lower rates of the combined endpoints of death, heart failure/shock, and/or reinfarction (11%) compared with patients without angina (23%; P = 0.04). They also had lower creatine kinase (CK) values. Therefore, preinfarction angina was protective in patients 60 years or older in the TIMI 4 study.

Journal Article↗
PubMed1995

Previous angina alters in-hospital outcome in TIMI 4. A clinical correlate to preconditioning?

BACKGROUND: Ischemic preconditioning has been shown to reduce myocardial infarct size in experimental models, but its role in patients remains unclear. Angina before myocardial infarction reflects brief episodes of ischemia and may be a marker of preconditioning. As part of the Thrombolysis in Myocardial Infarction (TIMI) 4 study, we performed an analysis on the effect of a history of previous angina on in-hospital outcomes for patients with acute myocardial infarction. METHODS AND RESULTS: Patients eligible for thrombolytic therapy were enrolled into the study. Data were collected from case report forms regarding previous history of angina, in-hospital outcome and 6-week follow-up. Two hundred eighteen patients had a history of previous angina at any time before acute myocardial infarction, and 198 patients did not have previous angina. Patients with any previous history of angina were less likely than with those without angina to experience in-hospital death (3% versus 8%) (P = .03), severe congestive heart failure (CHF) or shock (1% versus 7%, P = .006), or the combined end point of in-hospital death, severe CHF, or shock (4% versus 12%, P = .004). Moreover, patients with any history of angina were more likely to have a smaller creatine kinase (CK)-determined infarct size (119 versus 154 CK integrated units; P = .01) and were less likely to have Q waves on their ECG (57% versus 69%; P = .01). In the subset of patients who experienced angina within the 48 hours before infarction (compared with those who did not), there was a trend toward less likely in-hospital death (3% versus 6%; P = .09), a lower incidence of severe CHF or shock (1% versus 6% P = .008), a lower combined end point of death, CHF, or shock (3% versus 10%; P = .006), smaller infarct size assessed by CK (115 versus 151 CK units; P = .03), and a trend toward fewer Q-wave infarcts. However, patients with a history of previous angina did have a trend toward more recurrent ischemic pain. Of importance is that the beneficial in-hospital effects of previous angina were not dependent on angiographically visible coronary collaterals. CONCLUSIONS: Previous angina confers a beneficial effect on in-hospital outcome after acute myocardial infarction. The reasons for this benefit are uncertain, but one potential mechanism for this observation may be ischemic preconditioning.

Angina Pectoris↗
PubMed1995

Clinical aspects of preconditioning and implications for the cardiac surgeon.

Ischemic preconditioning is one of the most powerful means to reduce myocardial ischemic cell death in the experimental laboratory. Data are now emerging suggesting that ischemic preconditioning also can occur in the human heart. Studies performed on human myocardial biopsies, angioplasty studies, clinical studies assessing acute tolerance to angina, and some studies evaluating the effect of angina prior to myocardial infarction, lend support to the concept that the human heart can be preconditioned. The ultimate objective is to develop preconditioning-mimetic agents that can be administered prophylactically prior to the time of cardiopulmonary bypass surgery or administered to hearts that have been harvested for transplant in order to better preserve the ischemically jeopardized myocyte.

Angina Pectoris↗
PubMedDate not supplied

Ischemic preconditioning: implications for the geriatric heart.

Ischemic preconditioning is among the most consistent and powerful modes of reducing myocardial infarct size. Although several clinical studies have suggested that the human heart can be preconditioned, controversy exists in both the experimental and clinical literature as to whether the senescent heart can be preconditioned. The authors recently reported that older patients (> or = 60 years of age) in the Thrombolysis in Myocardial Infarction-4 study appeared to benefit from a history of angina prior to acute myocardial infarction. This observation may lead to a clinical counterpart to successful preconditioning in the older heart.

Aged↗