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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.dsr.2010.04.009 Byline: Patricia Briones-Fourzan, Cecilia Barradas-Ortiz, Fernando Negrete-Soto, Enrique Lozano-Alvarez Keywords: Caridea; Deep-sea reproduction; Pandalid shrimps; Reproductive trade-offs Abbreviations: BW, body weight; CL, carapace length; CL.sub.max, size of largest specimens in the sample; CL.sub.50, size at which 50% of females are ovigerous; CL.sub.[infinity], maximum theoretical size; SOM, size at the onset of sexual maturity; RSOM, relative size at the onset of sexual maturity (=SOM/CL.sub.[infinity]); ES, egg size; EMV, egg-mass volume; IRP, index of reproductive potential; PI, productivity index; RO, reproductive output. Abstract: Heterocarpus ensifer is a tropical deep-water pandalid shrimp whose reproductive features are poorly known. We examined reproductive traits of a population of H. ensifer inhabiting the continental slope (311-715m in depth) off the Yucatan Peninsula, Mexico (SW Gulf of Mexico). Size range of the total sample (n=816) was 10.4-38.9mm carapace length. Females grow larger than males, but both sexes mature at 57% of their maximum theoretical size and at [approximately equal to]30% of their total lifespan. Among adult females, the proportion of ovigerous females was high in all seasons, indicating year-round reproduction. Most females carrying embryos in advanced stages of development had ovaries in advanced stages of maturation, indicating production of successive spawns. In the autumn, however, the proportion of ovigerous females and the condition index of these females were lower compared to other seasons. This pattern potentially reflects a reduction in food resources following the summer minimum in particulate organic carbon flux to the deep benthos, as reported in previous studies. Spawns consisting of large numbers (16024[+ or -]5644, mean[+ or -]SD) of small eggs (0.045[+ or -]0.009mm.sup.3) are consistent with extended planktotrophic larval development, an uncommon feature in deep-water carideans. Egg number increased as a power function of female size but with substantial variability, and egg size varied widely within and between females. There was no apparent trade-off between egg number and egg size and neither of these two variables was influenced by female condition. These results indicate iteroparity and a high and variable reproductive effort, reflecting a reproductive strategy developed to compensate for high larval mortality. The present study provides a baseline to compare reproductive traits between Atlantic populations of this tropical deep-water pandalid. Author Affiliation: Universidad Nacional Autonoma de Mexico, Instituto de Ciencias del Mar y Limnologia, Unidad Academica Puerto Morelos. Ap. Postal 1152, Cancun, Quintana Roo 77500, Mexico Article History: Received 30 October 2009; Revised 20 March 2010; Accepted 23 April 2010

Study conducted on the reproduction and feeding habits of the giant isopods, Bathynomus giganteus, during different seasons, from the continental slope of the Yucatan Peninsula, Mexico is described. Results show that main reproductive activity occurs during winter and spring, when the food supply is the highest.

In healthy adults and animals, movement speeds are often chosen to reduce the energy expended; thus, is MS-related slowness of walking and arm reaching linked to increased effort costs? Here, we hypothesized that the costs of walking would be higher in MS due to gait-related impairments such as spasticity, balance deficits, or worsened fitness; whereas the costs of seated reaching would be no different due to its divorce from the sensorimotor covariates associated with elevated walking costs and low cardiorespiratory demand. Participants with MS (pwMS) (n=13) and age- and sex-matched controls (HCs) (n=11) first performed a battery of assessments. On two separate days, metabolic rates were measured via indirect calorimetry while participants walked on a treadmill at five speeds (0.6 up to 1.60m/s) and while performing out-and-back reaching movements with the dominant arm at five speeds (approx. 0.1 up to 0.8m/s). Neither age, height, nor weight differed between pwMS and HCs. The only metrics that differed between groups were the time to walk 25 feet (slower for pwMS) and fatigue ratings (higher for pwMS). Net metabolic rate (normalized to body mass) increased with walking speed (p<2e-16) and was ∼20.54% higher for pwMS at any speed than HCs (p=0.0185). However, the net rate (normalized to arm mass) was no different between pwMS and HCs at any speed (p=0.911). Elastic net regression techniques reinforced these findings: selecting MS-status as an important predictor of walking metabolic rate, while excluding this variable for predicting reaching rate, even when controlling for many additional factors. Individuals with MS who have high mobility and low disability may require more energy expenditure to walk, but not for seated reaching movements. Our results suggest that movement slowness occurring with MS is not altogether a consequence of energy conservation. Instead, other mechanisms such as fitness, perceived effort, or reward sensitivity should be investigated for improving mobility. [ABSTRACT FROM AUTHOR]

Background: Psoriasis has been related to a higher prevalence of cardiovascular risk factors. Vitamin-D deficiency has been associated with metabolic syndrome, cardiovascular disease, and psoriasis. However, there has been no comparative study on the effects of vitamin-D status between patients with and without psoriatic arthritis. Objective: The objective was to assess the relationship of 25-hydroxyvitamin D [25-(OH)D] levels with lipid and glucose metabolism parameters in psoriatic patients with and without arthritis. Methods: We studied 122 patients with psoriasis (61 without arthritis and 61 with arthritis) from the psoriasis unit (dermatology department) and rheumatology department of our hospital, analyzing lipid and glucose metabolism variables and serum 25-(OH)D concentrations. Measurements were conducted within a 2-month period to minimize seasonal bias in 25-(OH)D levels. Results: In the psoriatic patients without arthritis, serum 25-(OH)D levels were inversely correlated with fasting glucose (r = −0.285; P = .026), total cholesterol (r = −0.440; P = .000), low-density lipoprotein (r = −0.415; P = .001), total cholesterol/high-density lipoprotein (r = −0.303; P = .01), and triglyceride (r = −0.280; P = .029) values. This association remained statistically significant for glucose, total cholesterol, and low-density lipoprotein after controlling for confounding factors in multivariate analysis. No association was found between serum 25-(OH)D levels and any metabolic parameter in the patients with psoriatic arthritis. Limitations: This is a cross-sectional study that supports the hypothesis of an association between vitamin D and metabolic parameters but does not establish a causal relationship. Conclusions: Serum 25-(OH)D was inversely related to lipid and glucose metabolism parameters in psoriatic patients without arthritis, whereas no such association was observed in psoriatic patients with arthritis. Interventional studies are warranted to assess the effects of vitamin-D supplements on the metabolic profile of psoriatic patients without arthritis. [Copyright &y& Elsevier]

• Stable MS patients on long term natalizumab show modest decreases in brain volume. • Brain volume atrophy rates similar to age and gender matched healthy controls over 2 years. • Our results suggest normalization of brain atrophy on long term natalizumab use. Clinically stable multiple sclerosis (MS) patients often have negligible inflammatory MRI changes. Brain atrophy may provide insight into subclinical disease progression. The objective was to compare brain atrophy rates in stable patients on long term natalizumab treatment vs. age and gender matched healthy non-MS controls (HC) prospectively over two-years examining brain volume, cognition, and patient reported outcomes (PROs). MS patients treated with natalizumab for a minimum of 2 years, age 18-60 were recruited and compared with age- and gender-matched healthy controls (HC). Both groups were followed prospectively to obtain two years of consecutive magnetic resonance imaging, clinical and PRO data. Baseline normalized brain volume (NBV), yearly T2 lesion volume (T2LV), and percent brain volume change (PBVC) were measured using SIENAX, JIM 6.0, and SIENA respectively. Neuropsychological tests from the MACFIMS battery were selected to optimize assessments for impairments in the domains of information processing speed and memory. Patient reported outcomes (PROs) for domains of physical, mental and social quality of life were evaluated using the NeuroQol short forms. Forty-eight natalizumab and 62 HC completed all study visits. At baseline, unadjusted mean NBV (natalizumab=1508.80cm (Popescu et al., 2013) vs. HC=1539.23cm (Popescu et al., 2013); p=0.033) and median baseline T2LV (natalizumab=1724.62mm (Popescu et al., 2013) vs. HC=44.20mm (Popescu et al., 2013); p=<0.0001) were different. The mean PBVC at year 2, adjusted for gender and baseline age was -0.57% (CI: 0.7620, -0.3716) for natalizumab and -0.50% (-0.7208, -0.2831) for HC, but the difference between groups was not statistically significant (0.073%; p=0.62). Over the 2-year period, HC demonstrated mild improvements in some cognitive tests vs. natalizumab subjects. However, PROs were similar between the two groups. Stable MS patients on natalizumab have similar brain volume loss as people who do not have MS, suggesting normalization of brain atrophy. [ABSTRACT FROM AUTHOR]

Two isoforms of the translation initiation factor eIF4G, eIF4GI and eIF4GII, have been described in eukaryotic cells. The exact function of each isoform during the initiation of protein synthesis is still under investigation. We have developed an efficient and reliable method of expressing poliovirus 2Apro, which differentially proteolyzes eIF4GI and eIF4GII in a time- and dose-dependent manner. This system is based on the electroporation of an in vitro transcribed mRNA that contains the encephalomyocarditis virus internal ribosome entry site followed by the sequence of poliovirus 2Apro. In contrast to HeLa cells, expression of this protease in BHK-21 cells induces delayed hydrolysis kinetics of eIF4GI with respect to eIF4GII. Moreover, under these conditions the polyadenylate binding protein is not cleaved. Interestingly, translation of de novo synthesized luciferase mRNA is highly dependent on eIF4GI integrity, whereas ongoing translation is inhibited at the same time as eIF4GII cleavage. Moreover, reinitiation of a preexisting mRNA translation after polysome run-off is dependent on the integrity of eIF4GII. Notably, de novo translation of heat shock protein 70 mRNA depends little on eIF4GI integrity but is more susceptible to eIF4GII hydrolysis. Finally, translation of an mRNA containing encephalomyocarditis virus internal ribosome entry site when the two isoforms of eIF4G are differentially hydrolyzed has been examined. [ABSTRACT FROM AUTHOR]

Abstract: To better understand the development of ventral mesencephalic dopamine neurons, we performed subtractive hybridization screens to find ventral mesencephalic genes expressed at rat embryonic day 10 when these neurons begin to differentiate. The most commonly identified genes in these screens were members of the Bex (Brain expressed X-linked) gene family, rat Bex1 (Rex3), and a novel gene, rat Bex4. After identifying these genes, we then sought to characterize the Bex gene family. Two additional novel Bex genes (human Bex5 and mouse Bex6) were discovered through genomic databases. Bex5 is present in humans and monkeys, but not rodents, while Bex6 exists in mice, but not humans. Bex4 and Bex5 are localized to the X chromosome, are expressed in brain, and are similar in sequence. Bex4 and Bex5 are 54% and 56% identical to human Bex3 (pHGR74, NADE). Mouse Bex6 is on chromosome 16 and is 67% identical to mouse Bex4. Human Bex gene expression was studied with tissue expression arrays probed with specific oligonucleotides. Human Bex1 and Bex2 have similar expression patterns in the central nervous system with high levels in pituitary, cerebellum, and temporal lobe, and Bex1 is widely expressed outside of the central nervous system with high expression in the liver. Human Bex4 is highly expressed in heart, skeletal muscle, and liver, while Bex3 and Bex5 are more widely expressed. The subcellular localization of the Bex proteins varies from nuclear (rat Bex1) to cytoplasmic (rat Bex3, human Bex5, and mouse Bex6) and to both nuclear and cytoplasmic (rat Bex2 and rat Bex4). Rat Bex3, rat Bex4, human Bex5, and mouse Bex6 are degraded by the proteasome, while rat Bex1 or Bex2 are not. Rat Bex3 protein can likely bind transition metals through a histidine-rich domain. Because this gene family was originally named Bex and because these genes are unified by sequence similarity and gene structure, we believe the Bex nomenclature should prevail over nomenclature based on function (NADE) that has not been extended to the other Bex genes. We conclude that the Bex gene family members are highly homologous but differ in their expression patterns, subcellular localization, and degradation by the proteasome. [Copyright &y& Elsevier]

• US prescribing information recommends ocrelizumab be infused over 2.5 to 3 hours. • Shortening infusion time can reduce patient burden and optimize healthcare resources. • Patients showed good tolerability with ≈31% shorter infusion times. Ocrelizumab is an approved MS treatment administered as two 300-mg intravenous infusions 2 weeks apart (Dose 1), each lasting approximately 2.5 hours, followed by single 600-mg infusions every 6 months lasting approximately 3.5 hours. Our objective was to evaluate shorter-duration ocrelizumab infusions in the Phase IIIb open-label SaROD study (NCT03606460). Eligible patients received ocrelizumab 600-mg Dose 2 or 3 infused over approximately 2 hours (Cohort 1) or ocrelizumab 300-mg Dose 1, Infusion 2 over approximately 1.5 hours (Cohort 2). The primary endpoint was the number and proportion of patients experiencing Grade 3–4 infusion-related reactions (IRRs) in Cohort 1. Secondary endpoints included Grade 1–4 IRRs in both cohorts and Grade 3–4 IRRs in Cohort 2. Mean infusion times decreased by approximately 1.09 and 0.79 hours in Cohorts 1 and 2, respectively, compared with US prescribing information. IRRs, reported by 36% of 141 patients, were mild-to-moderate, with no observed Grade 3–4 IRRs. No IRR-related discontinuations occurred. No serious AEs, deaths, or new safety signals were observed. The IRR rate with ocrelizumab shorter-duration infusions was similar to that observed in the pivotal Phase III trials. Ocrelizumab can be infused over a shorter time without sacrificing patient safety. [ABSTRACT FROM AUTHOR]

• Sensory stimulation (TENS) improved performance on four tests of motor function in MS. • TENS improved self-reported level of walking limitations after the tests. • The improvement elicited by the concurrent application of TENS was immediate. • TENS was applied with an inexpensive, portable, and easy-to-use device. Multiple sclerosis (MS) symptoms reported in the first year of the disease include sensory impairment, fatigue, reduced mobility, and declines in hand function. The progressive reduction in motor function experienced by persons living with MS is invariably preceded by changes in sensory processing, which are strongly associated with the declines in both walking performance and manual dexterity. To assess the influence of concurrent sensory stimulation using augmented transcutaneous electrical nerve stimulation (aTENS) applied to leg and hand muscles on clinical tests of motor function in individuals whose mobility was compromised by MS. Thirteen persons with MS (52 ± 8 years; 6 women) and 12 age- and sex-matched healthy adults (52 ± 9 years) met the inclusion criteria. Participants visited the lab on two occasions with one week between visits. Each visit involved the participant performing four tests of motor function and completing two health-related questionnaires (PDDS and MSWS-12). The tests assessed walking performance (6-min test and 25-ft test), dynamic balance (chair-rise tes, and manual dexterity (grooved pegboard test). aTENS was applied through pads attached to the limbs over the tibialis anterior and rectus femoris muscles of the affected leg, and over the median nerve and the thenar eminence of the dominant hand. The pads were attached during both visits, but the current was only applied during the second visit. The stimulation comprised continuous asymmetrical biphasic pulses (0.2 ms) at a rate of 50 Hz and an intensity that elicited slight muscle contractions. At baseline and during both treatment sessions, the performance on all four tests of motor function was worse for the MS group than the Control group. The MS group experienced significant improvements in all outcomes during the aTENS session with medium-to-large effect sizes. PDDS ratings improved (from 2.8 ± 1.3 to 2.0 ± 1.5; effect size d = –0.70) and the MSWS–12 scores declined (from 36 ± 11 to 28 ± 12; effect size d = –1.52). The concurrent application of aTENS enabled the MS group to walk further during the 6-min test (from 397 ± 174 m to 415 ± 172 m; effect size d = 0.81), to complete the 25-ft test in less time (6.7 ± 3.0 s to 6.3 ± 2.9 s; effect size d = –0.76), to increase the counts in the chair-rise test (from 11.2 ± 3.8 to 13.6 ± 4.8; effect size d = 1.52), and to perform the grooved pegboard test more quickly (from 110 ± 43 s to 99 ± 37 s; effect size d = –0.98). The only significant effect for the Control group was a significant increase in the 6-min walk distance (from 725 ± 79 to 740 ± 82 m; effect size d = 0.87). Stimulation of sensory fibers with aTENS evoked clinically significant improvements in four tests of motor function and the self-reported level of walking limitations in persons who were moderately disabled by MS. Moreover, the improvements in function elicited by the concurrent application of aTENS were immediate. [ABSTRACT FROM AUTHOR]