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71.
In order to study the pattern of B cell involvement in acute nonlymphocytic leukemia (ANLL), multiple B lymphoid cell lines were established by Epstein-Barr virus transformation of peripheral blood mononuclear cells from two patients with the disease who were heterozygous for the X chromosome-linked glucose-6-phosphate dehydrogenase (G6PD). In one patient, the progenitor cells involved by the leukemia exhibited multipotent differentiative expression, whereas in the other patient the cells showed differentiative expression restricted to the granulocytic pathway. In the patient whose abnormal clone showed multipotent expression, the ratio of B-A G6PD in B lymphoid cell lines was skewed in the direction of type B (the enzyme characteristic of the leukemia clone) and significantly different from the 1:1 ratio expected. It is, therefore, likely that the neoplastic event occurred in a stem cell common to the lymphoid series as well as to the myeloid series. In contrast, evidence for B cell involvement was not detected in the patient whose ANLL progenitor cells exhibited restricted differentiative expression. These findings underscore the heterogeneity of ANLL. Clinically and morphologically similar malignancies in these two patients originated in progenitors with different patterns of stem cell differentiative expression. This difference may reflect differences in cause and pathogenesis. 相似文献
72.
Ross BD; Jacobson S; Villamil F; Korula J; Kreis R; Ernst T; Shonk T; Moats RA 《Radiology》1994,193(2):457
73.
The gender of the offspring is determined by the fertilizing sperm. Previous gender studies were based on washed sperm, but not on sperm in seminal plasma. The objective was to correlate motility parameters assessed during semen analyses with the offspring gender. For comparison, fixed sperm head DNA quantitated by Hoechst 33342 fluorescence microscopy was also analyzed. Forty-six patients undergoing assisted reproduction procedures resulted in livebirth deliveries with either male or female-predominant offsprings. Sperm head fluorescence was weakly correlated to the gender in 61% of the cases. Sperm of patients with male offsprings had slower curvilinear (44.2 +/- 1.8 mean +/- SEM, versus, 49.9 +/- 2.7 micro /sec) and slower average path velocities (32.4 +/- 1.2 versus 36.3 +/- 1.7 micro /sec). Using cut-off values for the curvilinear (< 49 micro /sec) and average path (< 36 micro /sec) velocities of sperm swimming in seminal plasma, the two parameters predicted 75 and 68% of the male offspring births, respectively. The data suggest that sperm movement in seminal plasma is a marker for factors that skew the ratio of the X- to Y-sperm populations. 相似文献
74.
Karen L. Hanson Dawn M. Schiehser Alexandra L. Clark Scott F. Sorg Russell T. Kim Mark W. Jacobson 《Journal of clinical and experimental neuropsychology》2016,38(10):1115-1130
Introduction: Given that little is known about the associations between alcohol use, cognition, and psychiatric symptoms among veterans with a history of mild traumatic brain injury (mTBI), we aimed to (a) characterize how they differ from veteran controls on a measure of problem drinking; (b) investigate whether problem drinking is associated with demographic or mTBI characteristics; and (c) examine the associations between alcohol use, mTBI history, psychiatric functioning, and cognition. Method: We assessed 59 veterans (n = 32 with mTBI history; n = 27 military controls) for problem alcohol use (Alcohol Use Disorders Identification Test: AUDIT), psychiatric symptoms, and neuropsychological functioning. Results: Compared to controls, veterans with mTBI history were more likely to score above the AUDIT cutoff score of 8 (p = .016), suggesting a higher rate of problem drinking. Participants with mTBI history also showed elevated psychiatric symptoms (ps < .001) and lower cognitive scores (ps < .05 to < .001). Veterans with higher AUDIT scores were younger (p = .05) and had less education (p < .01) and more psychiatric symptoms (ps < .01), but mTBI characteristics did not differ. After controlling for combat and mTBI history (R2 = .04, ns) and posttraumatic stress disorder (PTSD) symptoms (ΔR2 = .08, p = .05), we found that higher AUDIT scores were associated with poorer attention/processing speed, F(9, 37) = 2.55, p = .022; ΔR2 = .26, p = .03. Conclusions: This preliminary study suggested that veterans with mTBI history may be at increased risk for problem drinking. Problem alcohol use was primarily associated with more severe PTSD symptoms and poorer attention/processing speed, though not with combat or mTBI characteristics per se. Importantly, findings emphasize the importance of assessing for and treating problematic alcohol use and comorbid psychiatric symptoms among veterans, including those with a history of neurotrauma. 相似文献
75.
76.
Prevalence of conditions potentially associated with lower urinary tract symptoms in men 总被引:2,自引:0,他引:2
Gades NM Jacobson DJ Girman CJ Roberts RO Lieber MM Jacobsen SJ 《BJU international》2005,95(4):549-553
OBJECTIVE: To estimate the frequency of conditions associated with lower urinary tract symptoms (LUTS, typically included when assessing benign prostatic hyperplasia, BPH), as other causes of LUTS should be excluded when diagnosing BPH, using data from the Olmsted County Study of Urinary Symptoms and Health Status among Men. SUBJECTS AND METHODS: During 1989-91, Caucasian men aged 40-79 years were randomly selected from the Olmsted County population. Before contact, eligibility was determined by reviewing the community medical records. Baseline exclusion criteria included comorbid pre-existing conditions or treatments, e.g. prostate, bladder or lower back surgery, bladder neck contracture or cancer, diabetes with lower extremity amputation, and neurological diseases, including Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis, tabes dorsalis and stroke. Men with these conditions were excluded from the Olmsted County Study at baseline, because these conditions are potentially associated with LUTS. RESULTS: Of the 5100 randomly sampled men, 13.4% met at least one of the pre-existing exclusion criteria. Individually, the frequency of exclusions was 7.8% for prostate cancer or surgery, 4.8% for back surgery, 1.3% for bladder surgery and 1.4% for neurological conditions. All other conditions represented <1.0% of the study exclusions. Older men were more likely to meet at least one of the exclusion criteria, with men in their fifth to eighth decade having a total exclusion frequency of 1.4%, 5.4%, 8.5% and 32.8%, respectively. The most common reason for men in their fifth decade to be excluded was lower back surgery (0.9%), whereas the most common reason in the eighth was prostate surgery (21.8%). CONCLUSIONS: In men, conditions that may contribute to LUTS, other than BPH, are prevalent in the community and increase in frequency with age. It is important that other conditions associated with LUTS be excluded before a definitive diagnosis of BPH. Any oversight in this initial evaluation can potentially result in misclassification bias, misdiagnosis and incorrect treatment of patients. 相似文献
77.
Niti U. Trivedi Lisa M. Gargano Robert M. Brackbill Melanie H. Jacobson 《Journal of traumatic stress》2023,36(1):44-58
The September 11, 2001, terrorist attacks on the World Trade Center (WTC) in New York City (9/11) had health-related consequences, including posttraumatic stress disorder (PTSD). PTSD is associated with functional impairment, which varies by symptom severity and other factors. This study aimed to identify predictors of functional impairment in individuals with low versus high PTSD symptom severity levels. WTC Health Registry enrollees exposed to 9/11 were surveyed four times between 2003 and 2015; cumulated data for individuals who endorsed at least one symptom on the PTSD Checklist–Civilian Version (PCL-C) at Wave 4 (2015–2016) were included (N = 30,287) and examined cross-sectionally. Individuals were classified based on PCL-C scores as having low/no (2–29) or high levels of PTSD symptom severity (≥ 44). Functional impairment was defined as subsequent difficulties in daily living. Among low/no PTSD severity participants, adjusted odds ratios (aORs) for the associations between functional impairment and poor self-rated health (vs. good), low social support (vs. high), and no physical activity (vs. active) were 1.23–1.92. In the same group, low versus high household income was associated with more functional impairment, aOR = 1.34, 95% CI [1.13, 1.59]. Among participants with high-level PTSD symptoms, women, aOR = 1.70, 95% CI [1.31, 2.20], and Hispanic enrollees, aOR = 1.76, 95% CI [1.31, 2.36], were more likely to report an absence of impairment. Self-rated health, social support, and physical activity emerged as important predictors of PTSD-related functional impairment across PTSD symptom severity levels, supporting clinical interventions targeting these factors. 相似文献
78.
Yanli Zhou MD PhD Weihua Zhou PhD Russell D. Folks CNMT Daya N. Manatunga MS Arnold F. Jacobson MD PhD Jeroen J. Bax MD PhD Ernest V. Garcia PhD Ji Chen PhD FACC FASNC 《Journal of nuclear cardiology》2014,21(5):913-920
Objectives
The purpose of this study is to assess mIBG uptake in scar border zone and its relation with ventricular arrhythmia (VA) inducibility on electrophysiology (EP) testing using I-123 mIBG SPECT and resting Tc-99m SPECT myocardial perfusion imaging (MPI).Methods
Forty-seven patients from a previous clinical trial were retrospectively analyzed. These patients underwent I-123 mIBG and resting Tc-99m tetrofosmin SPECT, and EP testing. Twenty-eight patients were positive (EP+) and 19 patients were negative (EP?) for inducibility of sustained (>30 seconds) VA on EP testing. MPI scar extent, border zone extent, and mIBG uptake in border zone were used to predict VA inducibility on EP testing, respectively.Results
There was no significant difference in scar extent between the EP+ and EP? groups. The EP+ group had significantly larger border zone and lower mIBG uptake ratio in the border zone than the EP? group. Receiver operating characteristic (ROC) curve analysis showed that the prediction accuracy for border zone extent (area under ROC = 0.75) was better than scar extent (area under ROC = 0.66). The prediction accuracy was further improved (area under ROC = 0.78), when assessing mIBG uptake in the border zone.Conclusion
A new tool has been developed to measure scar and border zone and to assess mIBG uptake in scar and border zone from combined I-123 MIBG SPECT and resting Tc-99m SPECT MPI. The mIBG uptake in the border zone predicted VA inducibility on EP testing with a promising accuracy. 相似文献79.
Alayna E. Loiselle Gwynne A. Bragdon Justin A. Jacobson Sys Hasslund Zenia E. Cortes Edward M. Schwarz David J. Mitten Hani A. Awad Regis J. O'Keefe 《Journal of orthopaedic research》2009,27(6):833-840
Tendon injury frequently results in the formation of adhesions that reduce joint range of motion. To study the cellular, molecular, and biomechanical events involved in intrasynovial tendon healing and adhesion formation, we developed a murine flexor tendon healing model in which the flexor digitorum longus (FDL) tendon of C57BL/6 mice was transected and repaired using suture. This model was used to test the hypothesis that murine flexor tendons heal with differential expression of matrix metalloproteases (MMPs), resulting in the formation of scar tissue as well as the subsequent remodeling of scar and adhesions. Healing tendons were evaluated by histology, gene expression via real-time RT-PCR, and in situ hybridization, as well as biomechanical testing to assess the metatarsophalangeal (MTP) joint flexion range of motion (ROM) and the tensile failure properties. Tendons healed with a highly disorganized fibroblastic tissue response that was progressively remodeled through day 35 resulting in a more organized pattern of collagen fibers. Initial repair involved elevated levels of Mmp-9 at day 7, which is associated with catabolism of damaged collagen fibers. High levels of Col3 are consistent with scar tissue, and gradually transition to the expression of Col1. Scleraxis expression peaked at day 7, but the expression was limited to the original tendon adjacent to the injury site, and no expression was present in granulation tissue involved in the repair response. The MTP joint ROM with standardized force on the tendon was decreased on days 14 and 21 compared to day 0, indicating the presence of adhesions. Peak expressions of Mmp-2 and Mmp-14 were observed at day 21, associated with tendon remodeling. At day 28, two genes associated with neotendon formation, Smad8 and Gdf-5, were elevated and an improvement in MTP ROM occurred. Tensile strength of the tendon progressively increased, but by 63 days the repaired tendons had not reached the tensile strength of normal tendon. The murine model of primary tendon repair, described here, provides a novel mechanism to study the tendon healing process, and further enhances the understanding of this process at the molecular, cellular, and biomechanical level. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 833–840, 2009 相似文献
80.
OBJECTIVE. The objective was to determine the MR imaging findings that differentiate intact anterior cruciate ligament reconstruction graft, partial-thickness tear, and full-thickness tear, using arthroscopy as the gold standard. MATERIALS AND METHODS. Sixteen consecutive MR imaging examinations were retrospectively and independently evaluated by two musculoskeletal radiologists for primary signs (graft signal, orientation, fiber continuity, complete discontinuity, and thickness) and secondary signs (anterior tibial translation, uncovered posterior horn lateral meniscus, posterior cruciate ligament hyperbuckling, and abnormal posterior cruciate ligament line) of anterior cruciate ligament reconstruction graft tear in 15 patients with follow-up arthroscopy. Results were compared with arthroscopy, and both receiver operating characteristic curves and kappa values for interobserver variability were calculated. RESULTS. Arthroscopy revealed four full-thickness graft tears, seven partial-thickness tears, and five intact grafts. Of the primary signs, graft fiber continuity in the coronal plane and 100% graft thickness in the sagittal or coronal plane were most valuable in excluding full-thickness tear. Complete discontinuous graft in the coronal plane also was valuable in diagnosis of full-thickness tear. Of the secondary signs, anterior tibial translation and uncovered posterior horn lateral meniscus assisted in differentiating graft tear (partial or full thickness) from intact graft. The other primary and secondary signs were less valuable. Kappa values were highest for graft fiber continuity and graft discontinuity in the coronal plane. CONCLUSION. Full-thickness anterior cruciate ligament graft tear can be differentiated from partial-thickness tear or intact graft by evaluating for graft fiber continuity (coronal plane), complete graft discontinuity (coronal plane), and graft thickness (coronal or sagittal plane). 相似文献