[Classification and MR imaging of triangular fibrocartilage complex lesions]

OBJECTIVE

To explore the MRI characteristics of injuries of triangular fibrocartilage complex (TFCC), and provide imaging basis for the early diagnosis and treatment of the injuries.

METHODS

A total of 10 healthy volunteers without wrist injuries and 200 patients from Beijing Jishuitan Hospital who complained ulnar-sided wrist pain and were highly suspected as the injury of TFCC underwent the wrist magnetic resonance examination. All subjects were in a prone position and underwent examination on coronal T1WI scan and PD-FS on 3 planes respectively. Then the MRI characteristics of 3 healthy volunteers and 67 patients with TFCC injuries that confirmed by operation were analyzed. According to the comparative analysis of normal anatomy and Palmer classification, the injuries were classified and MRI features of different types of injuries were analyzed. At last, imaging findings were compared with surgical results.

RESULTS

Three healthy volunteers without injuries showed mainly in low signal intensity on T1WI and PD-FS images. According to Palmer classification, there were 52 traumatic injuries (ⅠA 9, ⅠB 25, ⅠC 3, ⅠD 13, In addition, 1 has central perforation and ulnar avulsion and 1 has ulnar and radial injuries simultaneously) and 15 degenerative injuries (ⅡA 5, ⅡB 1, ⅡC 2 , ⅡD 1 , ⅡE 6) among 67 patients. The central perforation mainly demonstrated as linear high signal perpendicular to the disk, and run in a sagittal line. The ulnar, distal, and radial avulsion mainly showed the injuries were irregular, the structures were ambiguous, and there was high signal intensity in the injured structures on PD-FS. Degenerative injuries demonstrated the irregularity of TFC and heterogeneous signals on PD-FS. There were mixed intermediate-high signals and changes in the articular cartilage of lunate and ulna, high signal in the lunotriquetral ligament and ulnocarpal or radioulnar arthritis.

CONCLUSION

MRI can demonstrate the anatomy of TFCC accurately, evaluate and make the general classification of injuries. It is of significance for the early diagnosis and treatment protocols of the TFCC injuries.

Interhemispheric functional and structural alterations and their relationships with alertness in unilateral temporal lobe epilepsy

OBJECTIVE

Many neuroimaging studies have shown that temporal lobe epilepsy (TLE) is associated with functional and structural abnormalities at specific brain areas. Unfortunately, relatively limited information has been presented about the alterations of interhemispheric functional and anatomic connectivity in patients with unilateral TLE. In the present study, we investigated interhemispheric functional connectivity using a voxel-mirrored homotopic connectivity (VMHC) method. We further revealed fractional anisotropy (FA) changes in the areas with abnormal VMHC values in TLE patients by diffusion tensor imaging (DTI). Moreover, their relationships with alertness in patients with drug-naïve unilateral TLE were also investigated.

PATIENTS AND METHODS

Forty-three patients with unilateral TLE (21 left TLE and 22 right TLE) and 20 normal controls (NC) were recruited for case-control study. All of the subjects underwent acquisition of resting-state functional magnetic resonance images, Mini-Mental State Examination (MMSE) and the attention network test. DTI images were collected in 26 patients with unilateral TLE (10 left TLE and 16 right TLE) and 20 NCs. Functional connectivity between bilateral homotopic voxels was calculated. Homotopic regions showing abnormal functional connectivity in patients were adopted as regions of interest for the analysis of DTI. The FA values, MMSE scores, and alertness were compared between groups. Correlation analyses were employed to examine the relationships between each radiographic parameter (VMHC and FA) and each clinical and neuropsychological parameter in patients with drug-naïve unilateral TLE.

RESULTS

Compared with NC, patients with left TLE exhibited significantly higher VMHC values in the bilateral angular gyrus, inferior occipital gyrus and superior parietal gyrus and lower VMHC values in the bilateral supplementary motor area, inferior parietal lobule, middle temporal gyrus, and medial superior frontal gyrus. In patients with right TLE, higher VMHC values were found in the bilateral inferior occipital gyrus, parahippocampal gyrus and cerebellum; lower VMHC values were observed in the bilateral middle temporal gyrus and precentral gyrus/inferior frontal gyrus. FA values of the commissural fiber bundles connecting the bilateral parahippocampal gyrus were smaller in the right TLE than those in the NC group. Meanwhile, the alerting effect of patients was determined to be impaired and positively correlated with FA values of the commissural fiber bundles connecting the bilateral parahippocampal gyrus in right TLE patients.

CONCLUSIONS

Our findings indicate that the bilateral parahippocampal gyrus may be important to the pathophysiology of patients with drug-naïve unilateral TLE. The significant correlation between the FA values and alertness indicates that structural changes are involved in the alterations in the alertness network in unilateral right TLE patients.

Evidence for Simultaneous Production of J/ψ and ϒ Mesons

We report evidence for the simultaneous production of J/ψ and ϒ mesons in 8.1  fb^{-1} of data collected at sqrt[s]=1.96  TeV by the D0 experiment at the Fermilab pp[over ¯] Tevatron Collider. Events with these characteristics are expected to be produced predominantly by gluon-gluon interactions. In this analysis, we extract the effective cross section characterizing the initial parton spatial distribution, σ_{eff}=2.2±0.7(stat)±0.9(syst)  mb.

Gold nanorods coated by oxygen-deficient TiO2 as an advanced photocatalyst for hydrogen evolution

Gold nanorods coated by oxygen-deficient TiO₂ are synthesized by slow hydrolysis followed with high-temperature annealing in a reducing atmosphere. The hydrogenated product Au@H-TiO₂ shows enhanced photocatalytic ability in hydrogen generation.

Rational design of MnO2@MnO2 hierarchical nanomaterials and their catalytic activities

Lavender-like α-MnO₂@α-MnO₂ and balsam pear-like α-MnO₂@γ-MnO₂ were prepared and α-MnO₂@γ-MnO₂ exhibited a better performance than that of α-MnO₂@α-MnO₂ in dimethyl ether combustion.

Inclusive Production of the X(4140) State in pp[over ¯] Collisions at D0

We present a study of the inclusive production of the X(4140) state with the decay to the J/ψϕ final state in hadronic collisions. Based on 10.4  fb^{-1} of pp[over ¯] collision data collected by the D0 experiment at the Fermilab Tevatron collider, we report the first evidence for the prompt production of an X(4140) state and find the fraction of X(4140) events originating from b hadrons to be f_{b}=0.39±0.07(stat)±0.10(syst). The ratio of the nonprompt X(4140) production rate to the B_{s}^{0} yield in the same channel is R=0.19±0.05(stat)±0.07(syst). The values of the mass M=4152.5±1.7(stat)_{-5.4}^{+6.2}(syst)  MeV and width Γ=16.3±5.6(stat)±11.4(syst)  MeV are consistent with previous measurements.

Search for Violation of CPT and Lorentz Invariance in Bs(0) Meson Oscillations

We present the first search for CPT-violating effects in the mixing of Bs(0) mesons using the full Run II data set with an integrated luminosity of 10.4  fb(-1) of proton-antiproton collisions collected using the D0 detector at the Fermilab Tevatron Collider. We measure the CPT-violating asymmetry in the decay Bs(0)→μ(±)Ds(±) as a function of celestial direction and sidereal phase. We find no evidence for CPT-violating effects and place limits on the direction and magnitude of flavor-dependent CPT- and Lorentz-invariance violating coupling coefficients. We find 95% confidence intervals of Δa⊥<1.2×10(-12)  GeV and (-0.8<ΔaT-0.396ΔaZ<3.9)×10(-13)  GeV.

Tevatron Combination of Single-Top-Quark Cross Sections and Determination of the Magnitude of the Cabibbo-Kobayashi-Maskawa Matrix Element V_{tb}

We present the final combination of CDF and D0 measurements of cross sections for single-top-quark production in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV. The data correspond to total integrated luminosities of up to 9.7 fb^{-1} per experiment. The t-channel cross section is measured to be σ_{t}=2.25_{-0.31}^{+0.29} pb. We also present the combinations of the two-dimensional measurements of the s- vs t-channel cross section. In addition, we give the combination of the s+t channel cross section measurement resulting in σ_{s+t}=3.30_{-0.40}^{+0.52} pb, without assuming the standard model value for the ratio σ_{s}/σ_{t}. The resulting value of the magnitude of the top-to-bottom quark coupling is |V_{tb}|=1.02_{-0.05}^{+0.06}, corresponding to |V_{tb}|>0.92 at the 95% C.L.

Two guard cell mitogen-activated protein kinases, MPK9 and MPK12, function in methyl jasmonate-induced stomatal closure in Arabidopsis thaliana

Methyl jasmonate (MeJA) and abscisic acid (ABA) signalling cascades share several signalling components in guard cells. We previously showed that two guard cell-preferential mitogen-activated protein kinases (MAPKs), MPK9 and MPK12, positively regulate ABA signalling in Arabidopsis thaliana. In this study, we examined whether these two MAP kinases function in MeJA signalling using genetic mutants for MPK9 and MPK12 combined with a pharmacological approach. MeJA induced stomatal closure in mpk9-1 and mpk12-1 single mutants as well as wild-type plants, but not in mpk9-1 mpk12-1 double mutants. Consistently, the MAPKK inhibitor PD98059 inhibited the MeJA-induced stomatal closure in wild-type plants. MeJA elicited reactive oxygen species (ROS) production and cytosolic alkalisation in guard cells of the mpk9-1, mpk12-1 and mpk9-1 mpk12-1 mutants, as well in wild-type plants. Furthermore, MeJA triggered elevation of cytosolic Ca(2+) concentration ([Ca(2+)]cyt ) in the mpk9-1 mpk12-1 double mutant as well as wild-type plants. Activation of S-type anion channels by MeJA was impaired in mpk9-1 mpk12-1. Together, these results indicate that MPK9 and MPK12 function upstream of S-type anion channel activation and downstream of ROS production, cytosolic alkalisation and [Ca(2+)]cyt elevation in guard cell MeJA signalling, suggesting that MPK9 and MPK12 are key regulators mediating both ABA and MeJA signalling in guard cells.

Measurement of the Effective Weak Mixing Angle in pp[over ¯]→Z/γ^{*}→e^{+}e^{-} Events

We present a measurement of the fundamental parameter of the standard model, the weak mixing angle sin^{2}θ_{eff}^{ℓ} which determines the relative strength of weak and electromagnetic interactions, in pp[over ¯]→Z/γ^{*}→e^{+}e^{-} events at a center of mass energy of 1.96 TeV, using data corresponding to 9.7 fb^{-1} of integrated luminosity collected by the D0 detector at the Fermilab Tevatron. The effective weak mixing angle is extracted from the forward-backward charge asymmetry as a function of the invariant mass around the Z boson pole. The measured value of sin^{2}θ_{eff}^{ℓ}=0.23147±0.00047 is the most precise measurement from light quark interactions to date, with a precision close to the best LEP and SLD results.

Effect of Mobile Phone Radiation on Cardiovascular Development of Chick Embryo

The biological effects on cardiovascular development of chicken embryos were examined after radiation exposure using mobile phone (900 MHz; specific absorption rate˜1.07 W/kg) intermittently 3 h per day during incubation. Samples were selected by morphological and histological methods. The results showed the rate of embryonic mortality and cardiac deformity increased significantly in exposed group (P < 0.05). No any histological pathological changes were observed on Day 5-7 (D5-D7) of incubation. A higher distribution of lipid droplets was unexpectedly present in myocardial tissue from the exposure groups on D10-D13. Soon afterwards, myofilament disruption, atrioventricular valve focal necrosis, mitochondria vacuolization and atrial natriuretic peptide (ANP) decrease appeared on D15-D21 of incubation. Comet assay data showed the haemocyte mean tail in the exposed group was significantly larger than that of the control (P < 0.01). The arterial vascular wall of exposed group was thicker (P < 0.05) than that of the control on D13, which was reversed to normal in later stages. Our findings suggest that long-term exposure of MPR may induce myocardium pathological changes, DNA damage and increased mortality; however, there was little effect on vascular development.

Cancer risk in the relatives of patients with nasopharyngeal carcinoma—a register-based cohort study in Sweden

BACKGROUND

Little is known about cancer susceptibility among relatives of nasopharyngeal carcinoma (NPC) patients in non-endemic areas. We conducted a register-based cohort study to assess the relative risks (RRs) of cancer in families of NPC probands in Sweden.

METHODS

By linking 11,602,616 Swedish-born individuals (defined as 'general population') identified from national censuses to the Swedish Cancer Register and Multi-Generation Register, we identified 9157 relatives (3645 first-degree and 5512 second-degree) of 1211 NPC probands. Cancer incidence during 1961-2009 was ascertained through the Cancer Register. Relative risks of cancer in the relatives of NPC probands, compared with the rest of the general population, were calculated from Poisson regression models.

RESULTS

First-degree relatives had higher risks of NPC (N=2, RR=4.29, 95% confidence interval (CI)=1.07 to 17.17) and cancers of the larynx (N=5, RR=2.53, 95% CI=1.05 to 6.09), prostate (N=76, RR=1.35, 95% CI=1.07 to 1.68), and thyroid (N=10, RR=2.44, 95% CI=1.31 to 4.53) than the rest of the general population. In addition, a raised risk of cancer of the salivary glands was observed among first-degree relatives of probands with undifferentiated NPC (N=2, RR=6.64, 95% CI=1.66 to 26.57). In contrast, a decreased risk of colorectal cancer was observed in first- and second-degree relatives (N=43, RR=0.71, 95% CI=0.53 to 0.96).

CONCLUSION

The increased risk of NPC and certain other cancers among first-degree relatives may be explained by shared genetic and environmental risk factors, the latter including Epstein-Barr virus infection and smoking or by increased diagnostic intensity.

The autoimmune spectrum of myasthenia gravis: a Swedish population-based study

OBJECTIVES

To determine the prevalence of myasthenia gravis (MG) and the rate of concurrent autoimmune diseases in patients with MG.

DESIGN AND SETTING

Using the Swedish health and population registers, during the period 2005-2010, we conducted a nested case-control study of patients with MG (n = 2045) with five age- and sex-matched population-based controls per case. Register-based MG diagnosis was validated against the Stockholm MG Cohort. Similar nested case-control studies were conducted in patients with multiple sclerosis (MS), as a neuroinflammatory disease control, and siblings of patients with MG.

MAIN OUTCOME MEASURE

Odds ratios (ORs) and their 95% confidence intervals (CIs) were calculated as a measure of the association between MG and other autoimmune diseases.

RESULTS

The prevalence of MG was 24.8/100,000, and patients with MG had an increased risk of another autoimmune disease compared to controls (22.0% vs. 8.9%; OR: 2.82, 95% CI: 2.49-3.20); this risk was stronger amongst younger persons and women. Polymyositis/dermatomyositis, systemic lupus erythematosus and Addison's disease, three conditions regulated by the HLA-B8-DR3 haplotype, were most strongly associated with MG, especially early-onset disease. HLA typing in the Stockholm MG Cohort showed that early-onset MG was indeed dominated by HLA-B8-DR3. The risk of another autoimmune disease was increased in both patients with MS and siblings of patients with MG, compared to their respective controls, but to a lesser extent than in patients with MG.

CONCLUSIONS

Our results suggest that MG shares risk factors with other autoimmune diseases, to a greater degree than MS, with a particular role of the HLA-B8-DR3 haplotype, especially amongst younger and female patients.

Tevatron constraints on models of the Higgs boson with exotic spin and parity using decays to bottom-antibottom quark pairs

Combined constraints from the CDF and D0 Collaborations on models of the Higgs boson with exotic spin J and parity P are presented and compared with results obtained assuming the standard model value JP=0+. Both collaborations analyzed approximately 10  fb(-) of proton-antiproton collisions with a center-of-mass energy of 1.96 TeV collected at the Fermilab Tevatron. Two models predicting exotic Higgs bosons with JP=0- and JP=2+ are tested. The kinematic properties of exotic Higgs boson production in association with a vector boson differ from those predicted for the standard model Higgs boson. Upper limits at the 95% credibility level on the production rates of the exotic Higgs bosons, expressed as fractions of the standard model Higgs boson production rate, are set at 0.36 for both the JP=0- hypothesis and the JP=2+ hypothesis. If the production rate times the branching ratio to a bottom-antibottom pair is the same as that predicted for the standard model Higgs boson, then the exotic bosons are excluded with significances of 5.0 standard deviations and 4.9 standard deviations for the JP=0- and JP=2+ hypotheses, respectively.

Individual maternal and child exposure to antibiotics in hospital - a national population-based validation study

AIM

Exposure to antibiotics in early life may affect future health. Most antibiotics are prescribed in outpatient care, but inpatient exposure is also important. We estimated how specific diagnoses in hospitals corresponded to individual antibiotic exposure.

METHODS

All pregnant women and children from birth to 5 years of age with infectious diseases and common inpatient diagnoses between July 2005 and November 2011 were identified from the Swedish National Patient Register. Random samples of individuals from predefined groups were drawn, and medical records received from the clinics were manually reviewed for antibiotics.

RESULTS

Medical records for 4319 hospital visits were requested and 3797 (88%) were received. A quarter (25%) of children diagnosed as premature had received antibiotics, and in children from one to 5 years of age, diagnoses associated with bacterial infections were more commonly treated with antibiotics (62.4-90.6%) than those associated with viruses (6.3-22.2%). Pregnant women who had undergone a Caesarean section were more likely to be treated with antibiotics than those who had had a vaginal delivery (40.1% versus 11.1%).

CONCLUSION

This study defines the proportion of new mothers and young children who received individual antibiotic treatment for specific inpatient diagnoses in Sweden and provides a useful basis for future studies focusing on antibiotic use.

Measurement of the B(s)(0) lifetime in the flavor-specific decay channel B(s)(0)→D(s)(-)μ(+)νX

We present an updated measurement of the B(s)(0) lifetime using the semileptonic decays B(s)(0)→D(s)(-)μ(+)νX, with D(s)(-)→ϕπ(-) and ϕ→K(+)K(-) (and the charge conjugate process). This measurement uses the full Tevatron Run II sample of proton-antiproton collisions at √[s]=1.96  TeV, comprising an integrated luminosity of 10.4  fb(-1). We find a flavor-specific lifetime τ(fs)(B(s)(0))=1.479±0.010(stat)±0.021(syst)  ps. This technique is also used to determine the B(0) lifetime using the analogous B(0)→D(-)μ(+)νX decay with D(-)→ϕπ(-) and ϕ→K(+)K(-), yielding τ(B(0))=1.534±0.019(stat)±0.021(syst)  ps. Both measurements are consistent with the current world averages, and the B(s)(0) lifetime measurement is one of the most precise to date. Taking advantage of the cancellation of systematic uncertainties, we determine the lifetime ratio τ(fs)(B(s)(0))/τ(B(0))=0.964±0.013(stat)±0.007(syst).

Measurement of the forward-backward asymmetry in the production of B(±) mesons in pp̄ collisions at √s=1.96 TeV

We present a measurement of the forward-backward asymmetry in the production of B(±) mesons, A(FB)(B(±)), using B(±)→J/ψK(±) decays in 10.4  fb(-1) of pp̄ collisions at sqrt[s]=1.96  TeV collected by the D0 experiment during Run II of the Tevatron collider. A nonzero asymmetry would indicate a preference for a particular flavor, i.e., b quark or ̄b antiquark, to be produced in the direction of the proton beam. We extract A(FB)(B(±)) from a maximum likelihood fit to the difference between the numbers of forward- and backward-produced B(±) mesons. We measure an asymmetry consistent with zero: A(FB)(B(±))=[-0.24±0.41  (stat)±0.19  (syst)]%.

First Report of Trichodorus obtusus on Turfgrass in North Carolina, U.S.A

In May 2014, 11 sandy soil samples were collected at a depth of about 5 to 15 cm from a golf course community in Wilmington, NC, composed of Bermudagrass (Cynodon dactylon) from the fairway, St. Augustinegrass (Stenotaphrum secundatum) from the lawn, and Zoysiagrass (Zoysia japonica) from the tee, all of which showed spotted yellowing and necrosis. Plant-parasitic nematodes were extracted from soil samples by a combination of elutriation and sugar centrifugal-flotation methods at the North Carolina Department of Agriculture and Consumer Services, Nematode Assay Lab, Raleigh, NC. The results revealed the presence of several plant-parasitic nematodes, with a stubby-root nematode (Trichodoridae) present. Population densities of stubby-root nematodes were 10 to 90 (average 50) nematodes per 500 cm³ of soil. This species was clearly different from the parthenogenetic stubby-root nematode Nanidorus minor (Colbran, 1956) Siddiqi, 1974 commonly found in North Carolina because of the presence of males and larger body size. Morphological and molecular analyses of this nematode identified the species as Trichodorus obtusus Cobb, 1913. Morphological features of T. obtusus specimens were examined in glycerol permanent mounts. Males (n = 5) had a ventrally curved spicule, three ventromedian precloacal papillae (one ventromedian cervical papilla anterior to the excretory pore, one pair of lateral cervical pores at the level of the ventromedian cervical papilla), and a tail with a non-thickened terminal cuticle. Males were 860 to 1,120 (average 1,018) μm long, body width 38 to 48 (42) μm, onchiostyle 53 to 60 (56) μm, and spicule 54 to 62 (59) μm. Females (n = 5) had a pore-like vulva, a barrel-shaped vagina, and one or two postadvulvar lateral body pores on each side. Females were 990 to 1,330 (1,148) μm long, body width 43 to 56 (48) μm, onchiostyle 50 to 64 (58) μm, and V 49.0 to 57.5% (53.0%). The morphology agreed with the description of T. obtusus (2). DNA was prepared by squashing a single nematode (n = 3) on a microscope slide and collecting in 50 μl of AE buffer (10 mM Tris-Cl, 0.5 mM EDTA; pH 9.0). The 18S rDNA region was amplified with the forward primers 18S-G18S4 (5' GCTTGTCTCAAAGATTAAGCC 3'), SSUF07 (AAAGATTAAGCCATGCATG), and 18S965 (GGCGATCAGATACCGCCCTAGTT) and reverse primers 18S-18P (TGATCCWKCYGCAGGTTCAC), SSUR26 (CATTCTTGGCAAATGCTTTCG), and 18S1573R (TACAAAGGGCAGGGACGTAAT). The 28S D2/D3 region was amplified with the forward primer 28S391a (AGCGGAGGAAAAGAAACTAA) and reverse primer 28S501 (TCGGAAGGAACCAGCTACTA) (4). The resulting 18S (1,547-bp) and 28S D2/D3 (925-bp) sequences were deposited in GenBank under the accession numbers KM276665 and KM276666. The 18S sequence data was 100% homologous with two populations of T. obtusus (JX279930, 898 bp, and JX289834, 897 bp) from South Carolina and one (AY146460, 634 bp) from an unknown source, each with a 1-bp difference in a Blastn search. The 28S D2/D3 sequence data was less than 90% homologous with many Trichodorus species, but no T. obtusus sequence data was available. T. obtusus is known to occur only in the United States and to damage turfgrasses. It is reported in the states of Virginia, Florida, South Carolina, Texas, Iowa, Kansas, Michigan, New York, and South Dakota. This nematode has been reported as a pathogen of bermudagrass in Florida (1) and South Carolina (3), but pathogenicity to St. Augustinegrass and Zoysiagrass is unknown. To our knowledge, this is the first report of T. obtusus on turfgrasses in North Carolina. References: (1) W. T. Crow and J. K. Welch. Nematropica 34:31, 2004. (2) W. Decraemer. The Family Trichodoridae: Stubby Root and Virus Vector Nematodes. Kluwer Academic Publishers, Dordrecht, The Netherlands, 1995. (3) J. B. Shaver et al. Plant Dis. 97:852, 2013. (4) G. R. Stirling et al. Nematology 15:401, 2013.

Association between diabetes and amyotrophic lateral sclerosis in Sweden

BACKGROUND AND PURPOSE

Energy metabolism is altered in patients with amyotrophic lateral sclerosis (ALS) but the role of diabetes is largely unknown.

METHODS

A population-based case-control study was conducted of 5108 ALS cases and 25,540 individually matched population controls during 1991-2010. Information on ALS and pre-existing diabetes was retrieved from the Swedish Patient Register to explore the association of ALS with diabetes overall and with insulin-dependent or non-insulin-dependent diabetes specifically. Variation of the association by diabetes duration and age was also studied.

RESULTS

In total, 224 ALS cases (4.39%) and 1437 controls (5.63%) had diabetes before the index date, leading to an overall inverse association between diabetes and ALS risk [odds ratio (OR) 0.79, 95% confidence interval (CI) 0.68-0.91]. The association was strong for non-insulin-dependent diabetes (OR 0.66, 95% CI 0.53-0.81) but not for insulin-dependent diabetes (OR 0.83, 95% CI 0.60-1.15) and varied as a function of diabetes duration, with the strongest association observed around 6 years after first ascertainment of diabetes. The association was age-specific; the inverse association was noted only amongst individuals aged 70 or older. In contrast, for younger individuals (<50 years), pre-existing insulin-dependent diabetes was associated with a higher ALS risk (OR 5.38, 95% CI 1.87-15.51).

CONCLUSIONS

Our study suggests that there is an association between diabetes and ALS, and highlights the importance of taking into account age, insulin dependence and diabetes duration. Future studies should explore whether the association is independent of body mass index.