Are LRRK2 p.G2019S or GBA1 variants associated with long-term outcomes of deep brain stimulation for Parkinson's disease?

BACKGROUND

Deep brain stimulation (DBS) is a well-established treatment option for individuals with advanced Parkinson's disease (PD). The potential influence of the LRRK2 p.G2019S or GBA1 variants on its lasting efficacy and adverse effects should be better characterized.

METHODS

We conducted a retrospective single-center case-control study involving PD patients who were carriers of a GBA1 variant (GBA1-PD), the LRRK2 p.G2019S variant (LRRK2-PD), and non-carriers (Nc-PD). All participants underwent DBS and were followed up for at least a year. Assessments before surgery and at 1, 2, 3, 5, and 10 years post-DBS included the following: the Movement Disorder Society's Unified PD Rating Scale (MDS-UPDRS) Part III, Hoehn and Yahr scale, Levodopa Equivalent Daily Dose (LEDD) and non-motor symptoms (psychotic episodes, depressive symptoms, and cognitive decline).

RESULTS

The sample was composed of 103 patients (72 males, mean age at DBS surgery 61.5 ± 8.7 years, mean postoperative follow-up 7.0 ± 4.1 years). Of these, 19 were LRRK2-PD, 20 GBA1-PD, and 64 were Nc-PD. No significant differences in motor outcomes were observed between the groups. Compared to the Nc-PD patients, the GBA1-PD patients were at increased risk of both psychotic episodes [hazard ratio (HR) 2.76 (95 % CI: 1.12-6.80), p = 0.027], and cognitive decline [HR 2.28 (95 % CI: 1.04-5.00), p = 0.04].

CONCLUSION

LRRK2 and GBA1 variant status did not affect the motor outcomes of DBS in PD patients. However, GBA1-PD patients were at increased risk for psychosis and cognitive decline. Further studies are required to determine the role of genetic stratification in referral to DBS.

Decreased amplitude of surface electromyo- graphic recordings of muscle activation along the posterior myofascial kinematic chain in subjects with chronic nonspecific low back pain compared to healthy subjects

BACKGROUND

The concept of myofascial continuity suggests that muscles activate along kinematic chains with common fascial coverings. Yet, the literature lacks evidence in regards to the function of anatomical chains in populations suffering from low back pain (LBP).

OBJECTIVE

To examine muscle activations along the superficial back line in LBP patients compared to healthy controls.

METHODS

The sample study included 20 males with chronic LBP (mean age 28.7 (± 3.05) years, mean BMI 24.91 (± 2.76)) and 17 healthy controls (mean age 31.06 (± 7.76) years, mean BMI 23.46 (± 3.43)). Muscle activation (gastrocnemius, hamstrings, erector spine, and upper trapezius) along the superficial back line was measured using surface EMG. All subjects underwent five test conditions: Conditions 1-3 involved passive movement, active movement and active movement against maximum isometric resistance of the right gastrocnemius muscle. Conditions 4 and 5 involved neck extension without and with isometric resistance from the prone position. The main outcome was relative muscle activation amplitude between research and control subjects.

RESULTS

Muscle activation along the posterior anatomical chain was observed during distal movement (plantar flexion or neck extension). LBP patients showed significant lower muscle activation in the erector spine of lower back region compared with the control group during active plantar flexion and active neck extension (p< 0.05). Lower muscle activation in other regions (gastrocnemius, hamstrings, erector spine level T6) was observed in the research group (although not significant).

CONCLUSION

LBP may cause or result in a lower muscle activation of the posterior kinematic myofascial chain muscles.

Can scintillation detectors with low spectral resolution accurately determine radionuclides content of building materials?

The current paper makes an attempt to check whether the scintillation NaI(Tl) detectors, in spite of their poor energy resolution, can determine accurately the content of NORM in building materials. The activity concentrations of natural radionuclides were measured using two types of detectors: (a) NaI(Tl) spectrometer equipped with the special software based on the matrix method of least squares, and (b) high-purity germanium spectrometer. Synthetic compositions with activity concentrations varying in a wide range, from 1/5 to 5 times median activity concentrations of the natural radionuclides available in the earth crust and the samples of popular building materials, such as concrete, pumice and gypsum, were tested, while the density of the tested samples changed in a wide range (from 860 up to 2,410 kg/m(3)). The results obtained in the NaI(Tl) system were similar to those obtained with the HPGe spectrometer, mostly within the uncertainty range. This comparison shows that scintillation spectrometers equipped with a special software aimed to compensate for the lower spectral resolution of NaI(Tl) detectors can be successfully used for the radiation control of mass construction products.

Measurement of radon diffusion length in thin membranes

Building regulations in Israel require the insulating of buildings against radon (222)Rn penetration from soil. In radon-prone areas membranes stretched between the soil and the building foundation are used, together with sealing other possible penetration routes. Designing the radon mitigation procedure requires checking that all sealing materials are practically, radon tight, having a thickness of at least three times the radon diffusion length. In this work, a very simple technique to evaluate the radon diffusion length in thin membranes, using a radon source of known activity and an activated charcoal canister as radon detector is presented. The theoretical formalism and measurement results for polyethylene membranes of different densities obtained in a recent comparison exercise are presented.

The study of natural radionuclides and radon exhalation rate in ceramic materials containing fly ash developed in Israel

The ionizing radiation dose from building materials containing fly ash (FA) has been studied. Ceramic products, plates, bricks and blocks containing fly ash have been studied and compared to other construction materials for both natural radionuclides content (NORM), radon exhalation rate and gamma radiation dose .The total radiation dose due to walls built from ceramic blocks containing FA (45% fly ash), was found to be lower than radiation doses due to walls of other construction materials, Assuming two walls (the exterior ones) built of this ceramic material the doses are 0.09-0.13 mSv/y for ceramic materials densities of 800 and 1200 kg/m3, respectively.

HPGe virtual point detector for radioactive disk sources

Validity of the model of a virtual point detector (implying existence of a point where all interactions virtually occur) was confirmed for measurements of radioactive disk sources with HPGe detectors. The existing correlation of the count rates with the distance between the virtual plain detector and the detector face makes it possible to inter- and extrapolate calibration curves for disk radioactive sources for use at different source-detector face distances. The dependence of the distance between the virtual plane detector and the detector face on the photon energy was studied for sources of various radii.

The dependence of the counting efficiency of Marinelli beakers for environmental samples on the density of the samples

The effect of the density of the radioactive material packed in a Marinelli beaker on the counting efficiency was studied. It was found that for all densities (0.4-1.7 g/cm(3)) studied the counting efficiency (epsilon) fits the linear log-log dependence on the photon energy (E) above 200 keV, i.e. obeying the equation epsilon=alphaE(beta) (alpha, beta-parameters). It was found that for each photon energy the counting efficiency is linearly dependent on the density (rho) of the matrix. epsilon=a-brho (a, b-parameters). The parameters of the linear dependence are energy dependent (linear log-log dependence), leading to a final equation for the counting efficiency of Marinelli beaker involving both density of the matrix and the photon energy: epsilon=alpha(1) x Ebeta1 - alpha2Ebeta2rho.

On the high-resolution gamma-ray spectrometric measurement of 40K in natural and synthetic materials

Many regulatory agencies require that all building materials and industrial waste be tested for their naturally occurring radioactive material (NORM) concentrations before they can be used or thrown away. Usually the NORM concentrations of 40K, 232Th and 238U are measured by gamma-ray spectrometry using high-purity germanium or NaI(Tl) detectors. 40K is measured through its 1460.8 keV gamma line, which is mixed with 1459.2 keV line of 228Ac from the chain of 232Th. This fact ignored till now, requires a correction in the computation of 40K concentration. Although in many cases the error is <1%, there are cases where there have been higher errors. It should be emphasised that even if the correction in 40K concentration is large, the correction of the external dose index is negligible owing to the weighing factor being higher for 232Th than for 40K (by at least a factor of 10).

Development and application of Marinelli beaker standards for monitoring radioactivity in Dairy-Products by gamma-ray spectrometry

Marinelli (reentrant) beakers are recommended for measurement of low-activity radioactive environmental samples, in both liquid and solid phase. The preparation of Marinelli beaker standards of milk powder containing 232ThO2 at secular equilibrium with its daughter radionuclides was studied. Standards were prepared by mixing of known amounts of solid ThO2 and milk powder. The densities of the standards were 0.5-0.7 kg dm(-3). Measurements of calibrated Marinelli beaker standards with HPGe detector showed that the energy dependence of the efficiency is similar to that of a point source, i.e. an almost linear dependence of log-efficiency vs. log-energy in the 200-2000 keV range, however the parabolic correlation fits better. The validity of these standards was checked by comparison with certified standard reference material IAEA-152-Milk powder containing radiocesium and radiopotassium. The results obtained were found to be in a good agreement with the published certified data. The limit of detection for the determination of radiocesium by gamma ray spectrometry under the prevailing experimental conditions is 0.03 Bq (i.e. 0.8 pCi), for samples of dairy products having lower densities of 0.7 kg dm(-1).

Biological and molecular characterization of a new cucurbit-infecting tobamovirus

ABSTRACT An uncharacterized virus was isolated from greenhouse-grown cucumber plants. Biological and serological data described in the present study indicated that the virus belonged in the genus Tobamovirus. The host range of the virus included several plant species within the family Cucurbitaceae. The virus designated Cucumber fruit mottle mosaic virus (CFMMV) causes severe mottling or mosaic on cucumber fruits, and its fast spread within greenhouses could lead to significant economic losses in cucumber crops. The genome of CFMMV has been completely sequenced and its genome organization was typical of a Tobamovirus. However, its sequence was distinct from other described viruses within the group of cucurbit-infecting Tobamoviruses. Comparisons of sequences and phylogenetic analysis suggested that the cucurbit-infecting Tobamoviruses be separated into two subgroups: subgroup I comprising the strains and isolates referred to in the literature as Cucumber green mottle mosaic virus (CGMMV) (CV3, CV4, CGMMV-W, CGMMV-SH, and CGMMV-Is) and subgroup II comprising CFMMV, Kyuri green mottle mosaic virus (KGMMV), and the Yodo strain of CGMMV, which is closely related to KGMMV and may be considered a strain of it.

Low-dose acetylsalicylic acid use and hemoglobin levels. Effects in a primary care population

OBJECTIVE

To determine the prevalence of acetylsalicylic acid therapy and effect of the drug on hemoglobin concentration over time.

DESIGN

Retrospective, observational study.

SETTING

Primary care population in a university-affiliated family medicine clinic.

PATIENTS

A population-based sample of 80 patients receiving low-dose ASA for secondary prevention of cardiovascular disease was studied. Of 84 patients receiving the drug after a cardiovascular problem, four were excluded: one man died of a recurrent stroke during the study; the file of a second man was unavailable; another man developed a bleeding ulcer; and one woman had been taking ASA for only 1 month when the data were collated.

MAIN OUTCOME MEASURES

Demographic variables of patients taking low-dose ASA, duration of ASA use, and two successive measures of hemoglobin level.

RESULTS

The frequency of ASA administration was 7.7% for men aged 60 and older and 2.9% for women. Women had no significant change in hemoglobin levels, while men had a mean loss of 0.472 g/dL (95% confidence interval, .198 to .746; P = .009). For the study population as a whole (80 patients), the average decline was 0.294 g/dL (95% confidence interval, .039 to .549; P = .029).

CONCLUSIONS

Although the clinical significance of these findings is uncertain, they suggest the need for a prospective investigation of the influence of low-dose ASA on hemoglobin levels.

Metabolism of 25-OH-vitamin D3 by peritoneal macrophages from CAPD patients

The active metabolite of vitamin D, 1,25-dihydroxycholecalciferol (1,25(OH)2D3), is produced mainly by the kidney, but there is evidence for extrarenal production in certain circumstances. We studied whether peritoneal macrophages (PM) from CAPD patients were capable of metabolizing 25-OH-D3 to 1,25(OH)2D3. We found that PM were able to metabolize 25-OH-D3 in vitro; the main product following 16 hours of incubation was 19-nor, 10-oxo, 25-OH-D3 with smaller amounts of 1,25(OH)2D3. However, after shorter incubations of three and five hours a larger portion of 1,25(OH)2D3 was produced. The metabolism of 25-OH-D3 was greatly enhanced in PM harvested during episodes of peritonitis. This property was specific for PM of CAPD patients, and was not found in PM from normal subjects. However, incubation of control PM with peritoneal effluent from CAPD patients resulted in induction of the ability of these cells to metabolize 25-OH-D3. This induction was enhanced by preincubation with peritoneal effluent from CAPD patients suffering from peritonitis. Prostaglandin E2 was found to be involved in this synthesis: addition of PGE2 to normal PM induced metabolism of 25-OH-D3, and incubation of PM from CAPD patients with indomethacin decreased the metabolism of 25-OH-D3. The vitamin D metabolites produced by PM from CAPD patients could have a role in immunological resistance to peritoneal infections.

Determination of trace amounts of cadmium, cobalt, chromium, iron, molybdenum, nickel, selenium, titanium, vanadium and zinc in blood and milk by neutron activation analysis

The concentrations of Cd, Co, Cr, Fe, Mo, Ni, Se, Ti, V and Zn in biological fluids, human blood serum and market milk were determined by neutron activation analysis, with enrichment by coprecipitation. The pre-concentration of these trace elements was accomplished by converting the dissolved trace metal ions into their pyrrolidinedithiocarbamate (1-pyrrolidinecarbodithioate) chelates, followed by coprecipitation with a metal carrier such as Ni, Pb or Bi. The coprecipitation was carried out prior to irradiation for the short-lived nuclides (V, Ti and Se) and after irradiation for the other elements. The validity of the method was checked using certified biological reference materials; the concentrations of trace elements found by the proposed method agreed well with the published certified data. The limits of detection for Cd, Co, Cr, Fe, Mo, Ni, Se (obtained through the long-lived isotope 75Se) and Zn under the present experimental conditions were found to be 5, 5, 10, 520, 5, 70, 10 and 150 ng, respectively, for 5 ml of biological liquor. The limits of detection for Ti and V obtained (through their short-lived radionuclides 51Ti and 52V, respectively) were found to be 180 and 1.4 ng, respectively, for 50 ml of market milk, or 70 and 0.7 ng for 1 ml of blood serum.

Halide concentrations in camel plasma in various states of hydration

Instrumental epithermal neutron activation analysis was used in determining the halide concentration of camel serum. The halides determined were sodium, chloride, bromide, and iodide. Serum was examined when the camels had free access to drinking water, following 10 d of water restriction and 2 h following rapid rehydration. When the camels were dehydrated there was a "serum storage" of iodide. This confirms the decline in thyroid metabolism previously described (15). Following rehydration the thyroid metabolism returned to normal. Dehydration also increased the serum bromide concentrations. This could have a tranquilizing effect, abetting the decrease in metabolism. There were no changes in sodium or chloride metabolism. It is concluded that use of neutron activation will allow an analysis of halides for physiological research.

Development of a reliable Hg-195m--Au-195m generator for the production of Au-195m, a short-lived nuclide for vascular imaging

A new mercury-195m (T1/2: 41 hr) leads to gold-195m (T1/2: 30.6 sec) generator suitable for first-pass as well as steady-state radionuclide angiography studies has been developed. The distribution coefficients, Kd, for mercury (Hg-195m) and gold (Au-196), experimentally evaluated on chelating resin Chelex 100, showed this resin to be suitable as the column packing. Mercury-195m in a Trisma buffer solution at pH 7.40 was loaded on a chelating resin Chelex 100 column, together with gold carrier. Au-195m was eluted with an aqueous solution of 5% glucose in a 0.01M Trisma buffer at pH 7.70 (25 degrees C). Chemical assessment of the eluate has ensured that the eluted carrier-free gold is by no means colloidal: 80% is found in an ionic form, 20% as an uncharged species. Safe clinical use for routine diagnosis in humans is possible.