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Background

Long-term postdiscectomy degenerative disc disease and low back pain is a well-recognized disorder; however, its patient-centered characterization and quantification are lacking.

Questions/purposes

We performed a systematic literature review and prospective longitudinal study to determine the frequency of recurrent back pain after discectomy and quantify its effect on patient-reported outcomes (PROs).

Methods

A MEDLINE search was performed to identify studies reporting on the frequency of recurrent back pain, same-level recurrent disc herniation, and reoperation after primary lumbar discectomy. After excluding studies that did not report the percentage of patients with persistent back or leg pain more than 6 months after discectomy or did not report the rate of same level recurrent herniation, 90 studies, which in aggregate had evaluated 21,180 patients, were included in the systematic review portion of this study. For the longitudinal study, all patients undergoing primary lumbar discectomy between October 2010 and March 2013 were enrolled into our prospective spine registry. One hundred fifteen patients were more than 12 months out from surgery, 103 (90%) of whom were available for 1-year outcomes assessment. PROs were prospectively assessed at baseline, 3 months, 1 year, and 2 years. The threshold of deterioration used to classify recurrent back pain was the minimum clinically important difference in back pain (Numeric Rating Scale Back Pain [NRS-BP]) or Disability (Oswestry Disability Index [ODI]), which were 2.5 of 10 points and 20 of 100 points, respectively.

Results Systematic Review

The proportion of patients reporting short-term (6–24 months) and long-term (> 24 months) recurrent back pain ranged from 3% to 34% and 5% to 36%, respectively. The 2-year incidence of recurrent disc herniation ranged from 0% to 23% and the frequency of reoperation ranged from 0% to 13%.

Prospective Study

At 1-year and 2-year followup, 22% and 26% patients reported worsening of low back pain (NRS: 5.3 ± 2.5 versus 2.7 ± 2.8, p < 0.001) or disability (ODI%: 32 ± 18 versus 21 ± 18, p < 0.001) compared with 3 months.

Conclusions

In a systematic literature review and prospective outcomes study, the frequency of same-level disc herniation requiring reoperation was 6%. Two-year recurrent low back pain may occur in 15% to 25% of patients depending on the level of recurrent pain considered clinically important, and this leads to worse PROs at 1 and 2 years postoperatively.  相似文献   
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Alteration of the TAL1 locus is the most common nonrandom genetic defect in childhood T-cell acute lymphoblastic leukemia (T-ALL). To determine if rearrangements of the TAL1 proto-oncogene confer a distinct leukemic phenotype, we studied leukemic peripheral blood or bone marrow samples from 182 children with newly diagnosed T-ALL enrolled on Pediatric Oncology Group treatment protocols. Forty-eight (26%) of the samples had a local rearrangement of the TAL1 locus. Demographic and clinical features were compared for patient subgroups with and without TAL1 rearrangements. The only clinical correlates that were significantly associated with TAL1 gene rearrangements were higher white blood cell count (P = .017) and higher hemoglobin (P = .007) at diagnosis. Immunophenotypically, samples with altered TAL1 were more likely to be CD2+ (P = .001) and lack CD10 (cALLa) expression (P = .007) than those without the rearrangement. There was a trend toward improved event-free survival (EFS) in patients with TAL1 rearrangements (4-year EFS was 44% +/- 7% for patients without the rearrangements v 59% +/- 11% for those with rearrangements), but the difference was not significant (P = .34). The role of TAL1 in leukemogenesis has yet to be clearly defined, and the prognostic significance of TAL1 gene rearrangements in T-ALL deserves further study.  相似文献   
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Two B-cell lines, 2F7 and 10C9, were established by single cell cloning from biopsies obtained from two acquired immune deficiency syndrome patients with Burkitt's lymphoma. Representation of the original tumors was verified by demonstration of (1) identical biallelic rearrangement of Ig genes for 2F7 and (2) shared idiotype for 10C9. Both cell lines displayed cell-surface Ig and secreted Ig (IgM lambda for 2F7, IgM kappa for 10C9). IgMs from both cell lines immunoprecipitated actin; in addition, 2F7 IgM lambda immunoprecipitated recombinant human immunodeficiency virus type 1 (HIV-1) gp 160. 2F7 IgM lambda did not react with other autoantigens (double-stranded and single-stranded DNA, actin, bovine serum albumin, IgG), whereas 10C9 IgM kappa reacted with human IgG. The 2F7 IgM heavy-chain variable region (VH) showed a 95% nucleotide homology with a previously sequenced VHIII germline gene, hv3019b9, whereas the 10C9 IgM VH showed a 95% homology with a previously sequenced VHIV germline gene, VH4.21. Use of minimally modified VH genes and demonstration of reactivity with chronically present antigens (ie, actin, HIV-1 gp 160, or human IgG) suggests that B cells in HIV-1-infected individuals proliferating in response to chronic antigenic stimulation may be at increased risk for lymphomagenesis.  相似文献   
36.
AIM:To investigate if the presence of relevant genetic polymorphisms has effect on the effectual clearance of bacteria by monocytes and granulocytes in patients with Crohn’s disease(CD).METHODS:In this study,we assessed the differential responses in phagocytosis by measuring the phagocytic activity and the percentage of active phagocytic monocytes and granulocytes in inflammatory bowel disease patients as well as healthy controls.As both autophagy related like 1(ATG16L1)and immunityrelated guanosine triphosphatase gene are autophagy genes associated with CD and more recently nucleo-tide-binding ligomerization domain-containing protein2(NOD2)has been identified as a potent inducer of autophagy we genotyped the patients for these variants and correlated this to the phagocytic reaction.The genotyping was done with restriction fragment length polymorphisms analysis and the phagocytosis was determined with the pHrodo?Escherichia coli Bioparticles Phagocytosis kit for flowcytometry.RESULTS:In this study,we demonstrate that analysis of the monocyte and granulocyte populations of patients with CD and ulcerative colitis showed a comparable phagocytic activity(ratio of mean fluorescence intensity)between the patient groups and the healthy controls.CD patients show a significantly higher phagocytic capacity(ratio mean percentage of phagocytic cells)compared to healthy controls(51.91%±2.85%vs 37.67%±7.06%,P=0.05).The extend of disease was not of influence.However,variants of ATG16L1(WT:2.03±0.19 vs homozygoot variant:4.38±0.37,P<0.009)as well as NOD2(C-ins)(heterozygous variant:42.08±2.94 vs homozygous variant:75.58±4.34(P=0.05)are associated with the phagocytic activity in patients with CD.CONCLUSION:Monocytes of CD patients show enhanced phagocytosis associated with the presence of ATG16L1 and NOD2 variants.This could be part of the pathophysiological mechanism resulting in the disease.  相似文献   
37.
The present article reports a case involving an immunocompetent, previously well child who, despite two previous doses of inactivated poliovirus vaccine, developed severe flaccid paralysis consistent with polio after receiving oral polio vaccine.  相似文献   
38.
Modern population based oral health management requires a complete understanding of the impact of disease in order to provide efficient and effective oral health care and guidance. Periodontitis is an important cause of tooth loss and has been shown to be associated with a number of systemic conditions. The impact of oral conditions and disorders on quality of life has been extensively studied. However, the impact of periodontitis on quality of life has received less attention. This review summarizes the literature on the impact of periodontitis on oral health‐related quality of life (OHRQoL). Relevant publications were identified after searching the MEDLINE and EMBASE electronic databases. Screening of titles and abstracts and data extraction was conducted. Only observational studies were included in this review. Most of the reviewed studies reported a negative impact of periodontitis on OHRQoL. However, the reporting standards varied across studies. Moreover, most of the studies were conducted in developed countries.  相似文献   
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