Abstract Background Context Transforaminal lumbar interbody fusion (TLIF) and posterior lumbar interbody fusion (PLIF) are both frequently used as surgical treatment for lumbar spondylolisthesis. Due ...to the unilateral transforaminal route to the intervertebral space used in TLIF, opposed to the bilateral route used in PLIF, TLIF could be associated with fewer complications, shorter duration of surgery, and less blood loss, while effectiveness of both techniques on back and/or leg pain is equal. Purpose To compare the effectiveness of both TLIF and PLIF in reducing disability, and to compare the intra- and postoperative complications of both techniques in patients with lumbar spondylolisthesis. Study Design/Setting A systematic literature review and meta-analysis was carried out. Methods We conducted a Medline (using Pubmed), Embase (using Ovid), Cochrane Library, Current Controlled Trials, ClinicalTrials.gov and NHS Centre for Review and Dissemination search for studies reporting TLIF, PLIF, lumbar spondylolisthesis and disability, pain, complications, duration of surgery and estimated blood loss. A meta-analysis was performed to compute pooled estimates of differences between TLIF and PLIF. Forest plots were constructed for each analysis group. Results 192 studies were identified, nine studies were included (one randomized controlled trial and eight case series), including 990 patients (450 TLIF and 540 PLIF). Pooled mean difference in postoperative ODI scores between TLIF and PLIF was -3.46 (95% CI -4.72, -2.20, p = <0.001). Pooled mean difference in postoperative VAS scores was -0.05 (95% CI -0.18, 0.09, p = 0.480). The overall complication rate for TLIF was 8.7% (range 0-25%), for PLIF 17.0% (range 4.7-28.8%), pooled odds ratio was 0.47 (95% CI 0.28, 0.81, p = 0.006). The average duration of surgery was 169 minutes for TLIF and 190 minutes for PLIF (mean difference -20.1, 95% CI -33.5, -6.6, p = 0.003). Estimated blood loss was 350 ml for TLIF and 418 ml for PLIF (mean difference -43.9 ml, 95% CI -71.2, -16.6, p = 0.002). Conclusions TLIF has advantages over PLIF in complication rate, blood loss and operation duration. Clinical outcome is similar, with a slightly lower postoperative ODI score for TLIF.
Organocatalysed asymmetric Mannich reactions Verkade, Jorge M M; van Hemert, Lieke J C; Quaedflieg, Peter J L M ...
Chemical Society reviews,
01/2008, Letnik:
37, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The asymmetric Mannich reaction ranks among the most potent enantioselective and diastereoselective C-C-bond forming reactions. In recent years, organocatalysed versions of asymmetric Mannich ...processes have been increasingly reported and used in a rapidly growing number of applications. This tutorial review provides an overview of the recent history of the asymmetric organocatalysed Mannich reaction, including scope and limitations, and application of different catalyst systems.
Abstract
Background
Up to 7% of all adrenal incidentalomas (AIs) are pheochromocytomas (PCCs). In the evaluation of AI, it is generally recommended that PCC be excluded by measurement of plasma-free ...or 24-hour urinary fractionated metanephrines. However, recent studies suggest that biochemical exclusion of PCC not be performed for lesions with CT characteristics of an adrenocortical adenoma (ACA).
Aim
To determine the proportion of PCCs with ACA-like attenuation or contrast washout on CT.
Methods
For this multicenter retrospective study, two central investigators independently analyzed the CT reports of 533 patients with 548 histologically confirmed PCCs. Data on tumor size, unenhanced Hounsfield units (HU), absolute percentage washout (APW), and relative percentage washout (RPW) were collected in addition to clinical parameters.
Results
Among the 376 PCCs for which unenhanced attenuation data were available, 374 had an attenuation of >10 HU (99.5%). In the two exceptions (0.5%), unenhanced attenuation was exactly 10 HU, which lies just within the range of ≤10 HU that would suggest a diagnosis of ACA. Of 76 PCCs with unenhanced HU > 10 and available washout data, 22 (28.9%) had a high APW and/or RPW, suggestive of ACA.
Conclusion
Based on the lack of PCCs with an unenhanced attenuation of <10 HU and the low proportion (0.5%) of PCCs with an attenuation of 10 HU, it seems reasonable to abstain from biochemical testing for PCC in AIs with an unenhanced attenuation of ≤10 HU. The assessment of contrast washout, however, is unreliable for ruling out PCC.
This retrospective study examined the CT characteristics of 548 PCCs. The findings suggest that biochemical testing for PCC be avoided in incidentalomas with unenhanced attenuation ≤ 10 HU.
Migraine, associated with several gastrointestinal disorders, may result from increased intestinal permeability, allowing endotoxins to enter the bloodstream. We tested whether probiotics could ...reduce migraine through an effect on intestinal permeability and inflammation.
In total, 63 patients were randomly allocated to the probiotic (n=31) or the placebo group (n=32). Participants ingested a multispecies probiotic (5x10
colony-forming units) or placebo daily for 12 weeks. Migraine was assessed with the Migraine Disability Assessment Scale (MIDAS), the Headache Disability Inventory (HDI) and headache diaries. At baseline and 12 weeks, intestinal permeability was measured with the urinary lactulose/mannitol test and fecal and serum zonulin; inflammation was measured from interleukin (IL) -6, IL-10, tumor necrosis factor-α and C-reactive protein in serum.
The MIDAS migraine intensity score significantly decreased in both groups (P<0.001) and the HDI score significantly decreased in the probiotic group (P=0.032) and borderline in the placebo group (P=0.053). In the probiotics group, patients had a median of 6 migraine days in the first month, 4 in the second month (P=0.002) and 5 in the last month, which was not significantly different from the 5, 4, and 4 days in the placebo group. A ⩾2day reduction in migraine days was seen in 12/31 patients in the probiotics group versus 7/29 in the placebo group (ns). Probiotic use did not significantly affect medication use, intestinal permeability or inflammation compared to placebo.
In this study, we could not confirm significant benefit from a multispecies probiotic compared to a placebo on the outcome parameters of migraine and intestinal integrity.
Recent years have shown steady progress towards molecular electronics, in which molecules form basic components such as switches, diodes and electronic mixers. Often, a scanning tunnelling microscope ...is used to address an individual molecule, although this arrangement does not provide long-term stability. Therefore, metal-molecule-metal links using break-junction devices have also been explored; however, it is difficult to establish unambiguously that a single molecule forms the contact. Here we show that a single hydrogen molecule can form a stable bridge between platinum electrodes. In contrast to results for organic molecules, the bridge has a nearly perfect conductance of one quantum unit, carried by a single channel. The hydrogen bridge represents a simple test system in which to understand fundamental transport properties of single-molecule devices.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The chikungunya virus (CHIKV) has become a substantial global health threat due to its massive re-emergence, the considerable disease burden and the lack of vaccines or therapeutics. We discovered a ...novel class of small molecules (1,2,3triazolo4,5-dpyrimidin-7(6H)-ones) with potent in vitro activity against CHIKV isolates from different geographical regions. Drug-resistant variants were selected and these carried a P34S substitution in non-structural protein 1 (nsP1), the main enzyme involved in alphavirus RNA capping. Biochemical assays using nsP1 of the related Venezuelan equine encephalitis virus revealed that the compounds specifically inhibit the guanylylation of nsP1. This is, to the best of our knowledge, the first report demonstrating that the alphavirus capping machinery is an excellent antiviral drug target. Considering the lack of options to treat CHIKV infections, this series of compounds with their unique (alphavirus-specific) target offers promise for the development of therapy for CHIKV infections.
ObjectivesDespite the availability of general and national guidelines for the conduct and reporting of economic evaluations, there is heterogeneity in economic evolutions concerning spine surgery. ...This is partly the result of differing levels of adherence to the existing guidelines and the lack of disease-specific recommendations for economic evaluations. The extensive heterogeneity in study design, follow-up duration and outcome measurements limit the comparability of economic evaluations in spine surgery. This study has three objectives: (1) to create disease-specific recommendations for the design and conduct of trial-based economic evaluations in spine surgery, (2) to define recommendations for reporting economic evaluations in spine surgery as a complement to the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) 2022 checklist and (3) to discuss methodological challenges and defining the need for future research.DesignA modified Delphi method according to the RAND/UCLA Appropriateness Method.SettingA four-step process was followed to create and validate disease-specific statements and recommendations for the conduct and reporting of trial-based economic evaluations in spine surgery. Consensus was defined as >75% agreement.ParticipantsA total of 20 experts were included in the expert group. Validation of the final recommendations was obtained in a Delphi panel, which consisted of 40 researchers in the field who were not included in the expert group.Primary and secondary outcome measuresThe primary outcome measure is a set of recommendations for the conduct and reporting, as a complement to the CHEERS 2022 checklist, of economic evaluations in spine surgery.ResultsA total of 31 recommendations are made. The Delphi panel confirmed consensus on all of the recommendations in the proposed guideline.ConclusionThis study provides an accessible and practical guideline for the conduct of trial-based economic evaluations in spine surgery. This disease-specific guideline is a complement to existing guidelines, and should aid in reaching uniformity and comparability.
The recently developed Social Exclusion Index for Health Surveys (SEI-HS) revealed particularly strong social exclusion in non-Western immigrant groups compared to the native Dutch population. To ...qualify such results, cross-cultural validation of the SEI-HS in non-Western immigrant groups is called for.
A sequential explanatory mixed methods design was used, employing quantitative data from the Netherlands Public Health Monitor along with qualitative interviews. Data from 1,803 adults aged 19 years or older of Surinamese, 1,009 of Moroccan and 1,164 of Turkish background and 19,318 native Dutch living in the four largest cities in the Netherlands were used to test the factorial structure of the SEI-HS and differential item functioning across immigrant groups. Additionally, 52 respondents with a high score on the SEI-HS and from different background were interviewed on the item content of the SEI-HS and subjective feelings of exclusion. For each SEI-HS item the semantic, conceptual and contextual connotations were coded and compared between the immigrant groups and native Dutch.
High levels of social exclusion were found in 20.0% of the urban population of Surinamese origin, 20.9% of Moroccan, 28.7% of Turkish and 4.2% of native Dutch origin. The 4-factor structure of the SEI-HS was confirmed in all three immigrant groups. None of the items demonstrated substantial differential item functioning in relation to immigration background. The interviews uncovered some methodological shortcomings, but these did not substantially impact the observed excess of social exclusion in immigrant groups.
The present study provides evidence in support of the validity of the SEI-HS in adults of Surinamese, Moroccan and Turkish background and confirms the major social exclusion of these immigrant groups in the main cities in the Netherlands. Policy measures to enhance social inclusion and reduce exclusion are urgently needed.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Purpose
Symptomatic lumbar spinal stenosis can be treated with decompression surgery. A recent review reported that, after decompression surgery, 1.6–32.0% of patients develop postoperative ...symptomatic spondylolisthesis and may therefore be indicated for lumbar fusion surgery. The latter can be more challenging due to the altered anatomy and scar tissue. It remains unclear why some patients get recurrent neurological complaints due to postoperative symptomatic spondylolisthesis, though some associations have been suggested. This study explores the association between key demographic, biological and radiological factors and postoperative symptomatic spondylolisthesis after lumbar decompression.
Methods
This retrospective cohort study included patients who had undergone lumbar spinal decompression surgery between January 2014 and December 2016 at one of two Spine Centres in the Netherlands or Switzerland and had a follow-up of two years. Patient characteristics, details of the surgical procedure and recurrent neurological complaints were retrieved from patient files. Preoperative MRI scans and conventional radiograms (CRs) of the lumbar spine were evaluated for multiple morphological characteristics. Postoperative spondylolisthesis was evaluated on postoperative MRI scans. For variables assessed on a whole patient basis, patients with and without postoperative symptomatic spondylolisthesis were compared. For variables assessed on the basis of the operated segment(s), surgical levels that did or did not develop postoperative spondylolisthesis were compared. Univariable and multivariable logistic regression analyses were used to identify associations with postoperative symptomatic spondylolisthesis.
Results
Seven hundred and sixteen patients with 1094 surgical levels were included in the analyses. (In total, 300 patients had undergone multilevel surgery.) ICCs for intraobserver and interobserver reliability of CR and MRI variables ranged between 0.81 and 0.99 and 0.67 and 0.97, respectively. In total, 66 of 716 included patients suffered from postoperative symptomatic spondylolisthesis (9.2%). Multivariable regression analyses of patient-basis variables showed that being female odds ratio (OR) 1.2, 95%CI 1.07–3.09 was associated with postoperative symptomatic spondylolisthesis. Higher BMI (OR 0.93, 95%CI 0.88–0.99) was associated with a lower probability of having postoperative symptomatic spondylolisthesis.
Multivariable regression analyses of surgical level-basis variables showed that levels with preoperative spondylolisthesis (OR 17.30, 95%CI 10.27–29.07) and the level of surgery, most importantly level L4L5 compared with levels L1L3 (OR 2.80, 95%CI 0.78–10.08), were associated with postoperative symptomatic spondylolisthesis; greater facet joint angles (i.e. less sagittal-oriented facets) were associated with a lower probability of postoperative symptomatic spondylolisthesis (OR 0.97, 95%CI 0.95–0.99).
Conclusion
Being female was associated with a higher probability of having postoperative symptomatic spondylolisthesis, while having a higher BMI was associated with a lower probability. When looking at factors related to postoperative symptomatic spondylolisthesis at the surgical level, preoperative spondylolisthesis, more sagittal orientated facet angles and surgical level (most significantly level L4L5 compared to levels L1L3) showed significant associations. These associations could be used as a basis for devising patient selection criteria, stratifying patients or performing subgroup analyses in future studies regarding decompression surgery with or without fusion.
ObjectivesThe present study is a systematic review conducted as part of a methodological approach to develop evidence-based recommendations for economic evaluations in spine surgery. The aim of this ...systematic review is to evaluate the methodology and quality of currently available clinical cost-effectiveness studies in spine surgery.Study designSystematic literature review.Data sourcesPubMed, Web of Science, Embase, Cochrane, Cumulative Index to Nursing and Allied Health Literature, EconLit and The National Institute for Health Research Economic Evaluation Database were searched through 8 December 2022.Eligibility criteria for selecting studiesStudies were included if they met all of the following eligibility criteria: (1) spine surgery, (2) the study cost-effectiveness and (3) clinical study. Model-based studies were excluded.Data extraction and synthesisThe following data items were extracted and evaluated: pathology, number of participants, intervention(s), year, country, study design, time horizon, comparator(s), utility measurement, effectivity measurement, costs measured, perspective, main result and study quality.Results130 economic evaluations were included. Seventy-four of these studies were retrospective studies. The majority of the studies had a time horizon shorter than 2 years. Utility measures varied between the EuroQol 5 dimensions and variations of the Short-Form Health Survey. Effect measures varied widely between Visual Analogue Scale for pain, Neck Disability Index, Oswestry Disability Index, reoperation rates and adverse events. All studies included direct costs from a healthcare perspective. Indirect costs were included in 47 studies. Total Consensus Health Economic Criteria scores ranged from 2 to 18, with a mean score of 12.0 over all 130 studies.ConclusionsThe comparability of economic evaluations in spine surgery is extremely low due to different study designs, follow-up duration and outcome measurements such as utility, effectiveness and costs. This illustrates the need for uniformity in conducting and reporting economic evaluations in spine surgery.