Association between MRI findings and clinical outcomes in a period of 5 years after lumbar spine microdiscectomy

European Journal of Orthopaedic Surgery & Traumatology - To evaluate the associations between magnetic resonance imaging (MRI) findings and pain, disability and quality of life before surgery...     

Presence of Cobalt and Chromium Ions in the Seminal Fluid of Young Patients With Metal-on-Metal Total Hip Arthroplasty

We aimed to investigate the effect of metal ions on the semen of males of child fathering age with metal-on-metal (MM) total hip arthroplasty (THA). Semen was collected form 11 patients with MM THA and 5 control of comparable age. Cobalt and chromiun concentrations were measured in both the seminal plasma and in the blood of patients. Results showed that cobalt level was higher in the seminal plasma of MM THA patients (2.89 μg/L) compared to control patients (1.12 μg/L) (P = .011). The ejaculate volume, the sperm density, the total sperm count, the pH, and the percentage of cells with normal morphology were in the range of the World Health Organization criteria for fertile population.     

Laparoscopic adrenalectomy in patients with subclinical Cushing syndrome

Background

Subclinical Cushing syndrome in patients with adrenal incidentalomas has been associated with an increased prevalence of the metabolic syndrome and cardiovascular risk. The management of these patients, be it conservative or surgical, is still debated, but there is accumulating evidence that surgery is best and that laparoscopic adrenalectomy, when possible, is the most preferred procedure. Here we present the short- and long-term results of laparoscopic adrenalectomy for subclinical Cushing syndrome and determine the effect of this procedure on components of the metabolic syndrome.

Methods

Twenty-nine patients, 8 men and 21 women with adrenal incidentalomas and subclinical Cushing syndrome who underwent laparoscopic adrenalectomy, were studied retrospectively. They had undergone postoperative follow-up for improvement or worsening of their arterial blood pressure, body weight, and fasting glucose level for a mean period of 77 months.

Results

Preoperatively, 17 patients (58.6 %) had arterial hypertension, 14 (48.3 %) had a body mass index exceeding 27 kg/m², and 12 (41.4 %) had diabetes mellitus. Postoperatively, a decrease in mean arterial pressure was found in 12 patients (70.6 %), a decrease in body mass index in 6 patients (42.9 %), and an improvement in glycemic control in 5 patients (41.7 %).

Conclusions

Laparoscopic adrenalectomy is beneficial in many patients with subclinical Cushing syndrome because it reduces arterial blood pressure, body weight, and fasting glucose levels. Prospective randomized studies are needed to compare laparoscopic adrenalectomy with a conservative approach and to confirm these results.     

Effects of intravenous zoledronic acid plus subcutaneous teriparatide [rhPTH(1–34)] in postmenopausal osteoporosis

Clinical data suggest concomitant therapy with bisphosphonates and parathyroid hormone (PTH) may blunt the anabolic effect of PTH; rodent models suggest that infrequently administered bisphosphonates may interact differently. To evaluate the effects of combination therapy with an intravenous infusion of zoledronic acid 5 mg and daily subcutaneous recombinant human (rh)PTH(1–34) (teriparatide) 20 µg versus either agent alone on bone mineral density (BMD) and bone turnover markers, we conducted a 1‐year multicenter, multinational, randomized, partial double‐blinded, controlled trial. 412 postmenopausal women with osteoporosis (mean age 65 ± 9 years) were randomized to a single infusion of zoledronic acid 5 mg plus daily subcutaneous teriparatide 20 µg (n = 137), zoledronic acid alone (n = 137), or teriparatide alone (n = 138). The primary endpoint was percentage increase in lumbar spine BMD (assessed by dual‐energy X‐ray absorptiometry [DXA]) at 52 weeks versus baseline. Secondary endpoints included change in BMD at the spine at earlier time points and at the total hip, trochanter, and femoral neck at all time points. At week 52, lumbar spine BMD had increased 7.5%, 7.0%, and 4.4% in the combination, teriparatide, and zoledronic acid groups, respectively (p < .001 for combination and teriparatide versus zoledronic acid). In the combination group, spine BMD increased more rapidly than with either agent alone (p < .001 versus both teriparatide and zoledronic acid at 13 and 26 weeks). Combination therapy increased total‐hip BMD more than teriparatide alone at all times (all p < .01) and more than zoledronic acid at 13 weeks (p < .05), with final 52‐week increments of 2.3%, 1.1%, and 2.2% in the combination, teriparatide, and zoledronic acid groups, respectively. With combination therapy, bone formation (assessed by serum N‐terminal propeptide of type I collagen [PINP]) increased from 0 to 4 weeks, declined minimally from 4 to 8 weeks, and then rose throughout the trial, with levels above baseline from 6 to 12 months. Bone resorption (assessed by serum β‐C‐telopeptide of type I collagen [β‐CTX]) was markedly reduced with combination therapy from 0 to 8 weeks (a reduction of similar magnitude to that seen with zoledronic acid alone), followed by a gradual increase after week 8, with levels remaining above baseline for the latter half of the year. Levels for both markers were significantly lower with combination therapy versus teriparatide alone (p < .002). Limitations of the study included its short duration, lack of endpoints beyond DXA‐based BMD (e.g., quantitative computed tomography and finite‐element modeling for bone strength), lack of teriparatide placebo, and insufficient power for fracture outcomes. We conclude that while teriparatide increases spine BMD more than zoledronic acid and zoledronic acid increases hip BMD more than teriparatide, combination therapy provides the largest, most rapid increments when both spine and hip sites are considered. © 2011 American Society for Bone and Mineral Research.     

The strength of combined cytogenetic and mate-pair sequencing techniques illustrated by a germline chromothripsis rearrangement involving FOXP2

Next-generation mate-pair sequencing (MPS) has revealed that many constitutional complex chromosomal rearrangements (CCRs) are associated with local shattering of chromosomal regions (chromothripsis). Although MPS promises to identify the molecular basis of the abnormal phenotypes associated with many CCRs, none of the reported mate-pair sequenced complex rearrangements have been simultaneously studied with state-of-the art molecular cytogenetic techniques. Here, we studied chromothripsis-associated CCR involving chromosomes 2, 5 and 7, associated with global developmental and psychomotor delay and severe speech disorder. We identified three truncated genes: CDH12, DGKB and FOXP2, confirming the role of FOXP2 in severe speech disorder, and suggestive roles of CDH12 and/or DGKB for the global developmental and psychomotor delay. Our study confirmes the power of MPS for detecting breakpoints and truncated genes at near nucleotide resolution in chromothripsis. However, only by combining MPS data with conventional G-banding and extensive fluorescence in situ hybridizations could we delineate the precise structure of the derivative chromosomes.     

Rapid dark aging of biomass burning as an overlooked source of oxidized organic aerosol

Oxidized organic aerosol (OOA) is a major component of ambient particulate matter, substantially impacting climate, human health, and ecosystems. OOA is readily produced in the presence of sunlight, and requires days of photooxidation to reach the levels observed in the atmosphere. High concentrations of OOA are thus expected in the summer; however, our current mechanistic understanding fails to explain elevated OOA during wintertime periods of low photochemical activity that coincide with periods of intense biomass burning. As a result, atmospheric models underpredict OOA concentrations by a factor of 3 to 5. Here we show that fresh emissions from biomass burning exposed to NO₂ and O₃ (precursors to the NO₃ radical) rapidly form OOA in the laboratory over a few hours and without any sunlight. The extent of oxidation is sensitive to relative humidity. The resulting OOA chemical composition is consistent with the observed OOA in field studies in major urban areas. Additionally, this dark chemical processing leads to significant enhancements in secondary nitrate aerosol, of which 50 to 60% is estimated to be organic. Simulations that include this understanding of dark chemical processing show that over 70% of organic aerosol from biomass burning is substantially influenced by dark oxidation. This rapid and extensive dark oxidation elevates the importance of nocturnal chemistry and biomass burning as a global source of OOA.

Highly oxidized organic aerosol (OOA) is a dominant component of particulate matter air pollution globally (1–3); however, sources of OOA remain uncertain, limiting the ability of models to accurately represent OOA and thus predict the associated climate, ecosystem, and health implications (4, 5). The current conceptual model of OOA formation suggests that anthropogenic OOA predominantly originates from the oxidation of volatile (VOCs), intermediate volatility (IVOCs), and semivolatile (SVOCs) organic compounds by the OH radical, resulting in lower-volatility products that condense to the particle phase (6). As the OH radical is formed through photolysis and has a very short atmospheric lifetime [less than a second (7)], this oxidation mechanism only occurs in the presence of sunlight. Further, the time scale for OOA formation through oxidation with OH in models is on the order of a few days (8). While this understanding is sufficient in explaining OOA concentrations in summer or periods with high solar radiation, atmospheric models fail to reproduce the observed concentration of OOA in the ambient atmosphere during winter and low-light conditions (9, 10). Fountoukis et al. (9) found simulated OOA concentrations significantly underestimated in wintertime Paris. Tsimpidi et al. (10) also reported an underprediction of simulated OOA globally in winter, suggesting missing sources of both primary OA (POA) and secondary formation pathways. This underproduction suggests a possible overlooked conversion pathway of organic vapors or particles to OOA that is not accounted for in current chemical transport and climate models.As stricter controls on fossil fuel combustion are implemented, residential biomass burning (BB) as a source of heating or cooking is becoming an increasingly important source of OA in urban environments (1, 11, 12). Further, increasing rates of wildfires from climate change are increasing the frequency of smoke-impacted days in urban areas (12–14). BB emissions include high concentrations of POA, SVOCs, IVOCs, and VOCs (15, 16), thus making BB a key source of OOA. Previous research has focused on quantifying the concentration of OOA formed through photochemical oxidation reactions (i.e., OH) with BB emissions (17, 18). However, oxidation of BB emissions in low or no sunlight is less well understood and is not included in chemical transport models. As opposed to OH, the NO₃ radical is formed through reactions with NO₂ and O₃ and is rapidly lost in the presence of sunlight (19). Thus, the NO₃ radical is only available in significant concentrations at night or other low-light conditions (20, 21). Previous research has established that biogenic VOCs may undergo oxidation at night when mixed with anthropogenic emissions containing NO₂ and O₃ (19, 22–27). There have been only a few studies that consider that nighttime oxidation of residential wood combustion may proceed through similar pathways (28–31); however, the magnitude and relevance to observed OOA in the ambient atmosphere has not yet been established. By combining laboratory experiments and ambient observations to inform a chemical transport model, we present strong evidence that nighttime oxidation of BB plumes (proceeding through reactions with O₃ and the NO₃ radical) is an important source of OOA.     

Further evidence for treatment of recalcitrant neuropathy of the upper limb with autologous vein wrapping

ABSTRACT: The treatment of entrapment neuropathy in the upper extremity with surgical decompression has generally provided good results. Recurrence of symptoms, however, is not uncommon, and its management is both challenging and difficult. Autologous vein graft wrapping is an alternative technique, and it is recommended for the treatment of recalcitrant upper limb nerve compression in which 2 or more previous surgical procedures have failed to resolve the problem. Each patient underwent both subjective and objective evaluation. To our knowledge, this is the largest reported single series of vein wrapping cases in the upper limb outside the United States and the first to report results using the well-validated patient evaluation measure.