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排序方式: 共有175条查询结果,搜索用时 15 毫秒
1.
Alex M. Hollenberg Noorullah Maqsoodi Amy Phan Aric Huber Ayodeji Jubril Avionna L. Baldwin Noriaki Yokogawa Roman A. Eliseev Addisu Mesfin 《The spine journal》2021,21(7):1205-1216
BACKGROUND CONTEXTBack and neck pain secondary to disc degeneration is a major public health burden. There is a need for therapeutic treatments to restore intervertebral disc (IVD) composition and function.PURPOSETo quantify ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression in IVD specimens collected from patients undergoing surgery for disc degeneration, to correlate ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression in IVD specimens to the 5-level Pfirrmann MRI grading system, and to compare ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression between cervical and lumbar degenerative disc specimens.STUDY DESIGNAn immunohistochemical study assessing ALK3, BMP-2, pSMAD1/5/8, and MMP-13 expression levels in human control and degenerative IVD specimens.METHODSHuman IVD specimens were collected from surgical patients who underwent discectomy and interbody fusion at our institution between 1/2015 and 8/2017. Each patient underwent MRI prior to surgery. The degree of disc degeneration was measured according to the 5-level Pfirrmann MRI grading system. Patients were categorized into either the 1) control group (Pfirrmann grades I-II) or 2) degenerative group (Pfirrmann grades III-V). Histology slides of the collected IVD specimens were prepared and immunohistochemical staining was performed to assess ALK3, BMP-2, pSMAD1/5/8, and MMP-13 expression levels in the control and degenerative specimens. Expression levels were also correlated to the Pfirrmann criteria. Lastly, the degenerative specimens were stratified according to their vertebral level and expression levels between the degenerative lumbar and cervical discs were compared.RESULTSFifty-two patients were enrolled; however, 2 control and 2 degenerative patients were excluded due to incomplete data sets. Of the remaining 48 patients, there were 12 control and 36 degenerative specimens. Degenerative specimens had increased expression levels of BMP-2 (p=.0006) and pSMAD1/5/8 (p<.0001). Pfirrmann grade 3 (p=.0365) and grade 4 (p=.0008) discs had significantly higher BMP-2 expression as compared to grade 2 discs. Pfirrmann grade 4 discs had higher pSMAD1/5/8 expression as compared to grade 2 discs (p<.0001). There were no differences in ALK3 or MMP-13 expression between the control and degenerative discs (p>.05). Stratifying the degenerative specimens according to their vertebral level showed no significant differences in expression levels between the lumbar and cervical discs (p>.05).CONCLUSIONSBMP-2 and pSMAD1/5/8 signaling activity was significantly upregulated in the human degenerative specimens, while ALK3 and MMP-13 expression were not significantly changed. The expression levels of BMP-2 and pSMAD1/5/8 correlate positively with the degree of disc degeneration measured according to the Pfirrmann MRI grading system.CLINICAL SIGNIFICANCEBMP-SMAD signaling represents a promising therapeutic target to restore IVD composition and function in the setting of disc degeneration. 相似文献
2.
L. A. DeFreest F. B. Mesfin L. Joseph D. J. McLeod A. Stallmer S. Reddy S. S. Balulad H. I. Jacobson T. T. Andersen J. A. Bennett 《Chemical biology & drug design》2004,63(5):409-419
Abstract: A synthetic peptide that inhibits the growth of estrogen receptor positive (ER+) human breast cancers, growing as xenografts in mice, has been reported. The cyclic 9‐mer peptide, cyclo[EMTOVNOGQ], is derived from α‐fetoprotein (AFP), a safe, naturally occurring human protein produced during pregnancy, which itself has anti‐estrogenic and anti‐breast cancer activity. To determine the pharmacophore of the peptide, a series of analogs was prepared using solid‐phase peptide synthesis. Analogs were screened in a 1‐day bioassay, which assessed their ability to inhibit the estrogen‐stimulated growth of uterus in immature mice. Deletion of glutamic acid, Glu1, abolished activity of the peptide, but glutamine (Gln) or asparagine (Asn) could be substituted for Glu1 without loss of activity. Methionine (Met2) was replaced with lysine (Lys) or tyrosine (Tyr) with retention of activity. Substitution of Lys for Met2 in the cyclic molecule resulted in a compound with activity comparable with the Met2‐containing cyclic molecule, but with a greater than twofold increase in purity and corresponding increase in yield. This Lys analog demonstrated anti‐breast cancer activity equivalent to that of the original Met‐containing peptide. Therefore, Met2 is not essential for biologic activity and substitution of Lys is synthetically advantageous. Threonine (Thr3) is a nonessential site, and can be substituted with serine (Ser), valine (Val), or alanine (Ala) without significant loss of activity. Hydroxyproline (Hyp), substituted in place of the naturally occurring prolines (Pro4, Pro7), allowed retention of activity and increased stability of the peptide during storage. Replacement of the first Pro (Pro4) with Ser maintains the activity of the peptide, but substitution of Ser for the second Pro (Pro7) abolishes the activity of the peptide. This suggests that the imino acid at residue 7 is important for conformation of the peptide, and the backbone atoms are part of the pharmacophore, but Pro4 is not essential. Valine (Val5) can be substituted only with branched‐chain amino acids (isoleucine, leucine or Thr); replacement by d ‐valine or Ala resulted in loss of biologic activity. Thus, for this site, the bulky branched side chain is essential. Asparagine (Asn6) is essential for activity. Substitution with Gln or aspartic acid (Asp), resulted in reduction of biologic activity. Removal of glycine (Gly8) resulted in a loss of activity but nonconservative substitutions can be made at this site without a loss of activity indicating that it is not part of the pharmacophore. Cyclization of the peptide is facilitated by addition of Gln9, but this residue does not occur in AFP nor is it necessary for activity. Gln9 can be replaced with Asn, resulting in a molecule with similar activity. These data indicate that the pharmacophore of the peptide includes side chains of Val5 and Asn6 and backbone atoms contributed by Thr3, Val5, Asn6, Hyp7 and Gly8. Met2 and Gln9 can be modified or replaced. Glu1 can be replaced with charged amino acids, and is not likely to be part of the binding site of the peptide. The results of this study provide information that will be helpful in the rational modification of cyclo[EMTOVNOGQ] to yield peptide analogs and peptidomimetics with advantages in synthesis, pharmacologic properties, and biologic activity. 相似文献
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Chandra L. Ford Mesfin S. Mulatu Dionne C. Godette Tommi L. Gaines 《Public health reports (Washington, D.C. : 1974)》2015,130(5):514-525
Objective
This study examined temporal trends in HIV testing among U.S. older adults (50–64 years of age) before and after the release of CDC''s routine HIV testing recommendations in 2006.Methods
The sample (n=872,797; 51.4% female) comprised 2003–2010 Behavioral Risk Factor Surveillance System respondents in the oldest categories to which the recommendations apply: 50–54 years (34.5%, n=301,519), 55–59 years (34.1%, n=297,865), and 60–64 years (31.3%, n=273,413). We calculated (1) four-year pooled prevalences of past-year HIV testing before and after 2006, when the recommendations were released; and (2) annual prevalences of HIV testing overall and by age category from 2003–2010. Using weighted, multivariable logistic regression analyses, we examined binary (pre- vs. post-recommendations) and annual changes in testing, controlling for covariates. We stratified the data by recent doctor visits, examined racial/ethnic differences, and tested for linear and quadratic temporal trends.Results
Overall and within age categories, the pooled prevalence of past-year HIV testing decreased following release of the recommendations (p<0.001). The annual prevalence decreased monotonically from 2003 (5.5%) to 2006 (3.6%) (b=–0.16, p<0.001) and then increased immediately after release of the recommendations, but decreased to 3.7% after 2009 (b=0.01, p<0.001). By race/ethnicity, testing increased over time among non-Hispanic black people only. Annual prevalence also increased among respondents with recent doctor visits.Conclusion
CDC''s HIV testing recommendations were associated with a reversal in the downward trend in past-year HIV testing among older adults; however, the gains were neither universal nor sustained over time.In 2006, the Centers for Disease Control and Prevention (CDC) began recommending routine opt-out human immunodeficiency virus (HIV) testing of all adults <65 years of age seeking health care in any setting where HIV prevalence is ≥0.1%.1 Routine testing is an efficient, cost-effective strategy for early detection of HIV infection.2 It involves screening every patient (except those who decline testing) regardless of any reported risk behaviors; therefore, it can facilitate detection of undiagnosed HIV infection among people unlikely to seek an HIV test, including those presumed to have little or no HIV risk.3Routine testing may be particularly important for older adults (i.e., those aged ≥50 years), among whom 11% of U.S. HIV infections occur. Of concern, HIV-infected older adults are disproportionately diagnosed late in the course of HIV disease.4,5 Late diagnosis is associated with rapid progression to acquired immunodeficiency syndrome (AIDS), and it exacerbates the management of both HIV disease and the non-HIV conditions that are prevalent among older adults (e.g., hypertension).6–9 Rates of HIV testing generally decrease with age;10–13 however, it is unclear if the release and implementation of the recommendations have helped to improve HIV testing levels in this age group.14,15To understand the recommendations'' potential influence on HIV testing among older adults, we examined trends in HIV testing from January 1, 2003, to December 31, 2010, among Behavioral Risk Factor Surveillance System (BRFSS) respondents in the three categories of older adulthood (50–54, 55–59, and 60–64 years of age) to which the routine HIV testing recommendations apply. The study period began four years prior to CDC''s publication of the recommendations and concluded four years thereafter, enabling us to compare HIV testing levels before and after their release. Full implementation should produce a sustained increase in testing that begins in 2007 and is most apparent among people with a recent doctor visit. This study sought to determine if:- The annual prevalence of past-year HIV testing increased among older adults since release of the routine HIV testing recommendations,
- Racial/ethnic differences in past-year HIV testing exist over time among older adults,
- The odds of testing increased more for those with vs. without a recent doctor visit since release of the recommendations, and
- The characteristics of older testers changed over time.
5.
Mesfin N Deribew A Yami A Solomon T Van Geertruyden JP Colebunders R 《International journal of STD & AIDS》2012,23(2):94-98
Little is known about the predictors of antiretroviral treatment (ART)-associated tuberculosis (TB) in developing nations. The objective of this study was to determine predictors of ART-associated TB in adults with HIV infection at Jimma University Hospital, Ethiopia. A nested case-control study was conducted in October 2009. The study population consisted of adults with HIV infection (aged >14 years) who developed active TB in the first six months since ART initiation and controls that did not develop active TB. Data were collected using a structured and pretested questionnaire. Cox proportions hazards analysis was done to determine predictors of ART-associated TB. A total of 357 patients (119 cases and 238 controls) participated in the study. After six months of follow-up, cumulative incidence of ART-associated TB was 5.2% (123/2355). Forty (33.6%) cases were lost to follow-up after they developed ART-associated TB and 11 (9.2%) died. Fifty-one (21.4%) controls interrupted ART and 11 (4.6%) died. A CD4 lymphocyte count increase >0.5/μL/day (adjusted hazard ratio [AHR] = 19.80, 95% confidence interval [CI]: 9.52, 41.12, P < 0.001), a base-line CD4 lymphocyte count <200 cells/μL (AHR = 9.59, 95% CI: 2.36, 39.04, P = 0.002), World Health Organization (WHO) clinical stage 3 or 4 (AHR = 3.04, 95% CI: 1.62, 5.69, P < 0.001), night sweats during ART initiation (AHR = 1.53, 95% CI: 1.06, 2.21, P < 0.001) and high ART adherence (AHR = 1.30, 95% CI: 1.13, 1.50, P < 0.001) were independent predictors of ART-associated TB. HIV-infected adults with these risk factors should be followed cautiously for the development of ART-associated TB. Good ART adherence and a good immunological response during ART were associated with ART-associated TB, most likely because of an immune reconstitution inflammatory syndrome unmasking the TB. 相似文献
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Addisu Mesfin Lawrence G. Lenke Keith H. Bridwell Usman Akhtar Jennifer M. Jupitz Jeremy L. Fogelson Stuart H. Hershman Han J. Kim Linda A. Koester 《The spine journal》2014,14(12):2819-2825
Background contextThe role of preoperative (preop) narcotic use and its influence on outcomes after spinal deformity surgery are unknown. It is important to determine which patient factors and comorbidities can affect the success of spinal deformity surgery, a challenging surgery with high rates of complications at baseline.PurposeTo evaluate if preop narcotic use persists after spinal deformity surgery and whether the outcomes are adversely affected by preop narcotic use.Study design/settingRetrospective evaluation of prospectively collected data.Patient sampleTwo hundred fifty-three adult patients (230 females/23 males) undergoing primary spinal deformity surgery were enrolled from 2000 to 2009.Outcome measuresPreoperative and postoperative (postop) narcotic use and changes in Oswestry Disability Index (ODI), Scoliosis Research Society (SRS) pain, and SRS total scores.MethodsPreoperative, 2-year postop, and latest follow-up pain medication use were collected along with ODI, SRS pain, and SRS scores. Preoperative insurance status, surgical and hospitalization demographics, and complications were collected. All patients had a minimum 2-year follow-up (average 47.4 months).ResultsOne hundred sixty-eight nonnarcotic (NoNarc) patients were taking no pain meds or only nonsteroidal anti-inflammatories preoperatively. Eighty-five patients were taking mild/moderate/heavy narcotics before surgery. The average age was 48.2 years for the NoNarc group versus 53.6 years for the Narc group (p<.005). There were significantly more patients with degenerative than adult scoliosis in the Narc group (47 vs. 28, p<.001; mild 19 vs. 24, p<.02; moderate 6 vs. 14, p<.0003; heavy 3 vs. 10, p<.0002). Insurance status (private/Medicare/Medicaid) was similar between the groups (p=.39). At latest follow-up, 137/156 (88%) prior NoNarc patients were still not taking narcotics whereas 48/79 (61%) prior narcotic patients were now off narcotics (p<.001). Significant postop improvements were seen in Narc versus NoNarc groups with regard to ODI (26–15 vs. 44–30.3, p<.001), SRS pain (3.36–3.9 vs. 2.3–3.38, p<.001), and overall SRS outcome (3.36–4 vs. 2.78–3.68, p<.001) scores. A comparison of change in outcome scores between the two groups showed a higher improvement in SRS pain scores for the Narc versus NoNarc group (p<.001).ConclusionsIn adults with degenerative scoliosis taking narcotics a significant decrease in pain medication use was noted after surgery. All outcome scores significantly improved postop in both groups. However, the Narc group had significantly greater improvements in SRS pain scores versus the NoNarc group. 相似文献
8.
L. E. H. Vanlinthout S. H. Mesfin N. Hens B. F. Vanacker E. N. Robertson L. H. D. J. Booij 《Anaesthesia》2014,69(12):1377-1387
We systematically reviewed factors associated with intubation conditions in randomised controlled trials of mivacurium, using random‐effects meta‐regression analysis. We included 29 studies of 1050 healthy participants. Four factors explained 72.9% of the variation in the probability of excellent intubation conditions: mivacurium dose, 24.4%; opioid use, 29.9%; time to intubation and age together, 18.6%. The odds ratio (95% CI) for excellent intubation was 3.14 (1.65–5.73) for doubling the mivacurium dose, 5.99 (2.14–15.18) for adding opioids to the intubation sequence, and 6.55 (6.01–7.74) for increasing the delay between mivacurium injection and airway insertion from 1 to 2 min in subjects aged 25 years and 2.17 (2.01–2.69) for subjects aged 70 years, p < 0.001 for all. We conclude that good conditions for tracheal intubation are more likely by delaying laryngoscopy after injecting a higher dose of mivacurium with an opioid, particularly in older people. 相似文献
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