Heading in soccer: dangerous play?

Soccer is the world's most popular sport and unique in that players use their unprotected heads to intentionally deflect, stop, or redirect the ball for both offensive and defensive strategies. Headed balls travel at high velocity pre- and postimpact. Players, coaches, parents, and physicians are justifiably concerned with soccer heading injury risk. Furthermore, risk of long-term neurocognitive and motor deficits caused by repetitively heading a soccer ball remains unknown. We review the theoretical concerns, the results of biomechanical laboratory experiments, and the available clinical data regarding the effects of chronic, subconcussive head injury during heading in soccer.     

Small-dense low-density lipoproteins are the predominant apoB-100-containing lipoproteins in cord blood

Objectives

Low density lipoprotein (LDL)-cholesterol level in cord blood is approximately 30%. The aim of our study was to specifically explore LDL apoB distribution across sizes in cord blood serum.

Design and methods

We studied 83 healthy neonates and 17 paired healthy mothers. Plasma glucose and serum lipids, such as low-density lipoprotein (LDL) cholesterol (LDL-C), HDL cholesterol (HDL-C) and triglycerides (TG), were measured using enzymatic methods. Distribution of apoB-100 was performed by western blot and immunodetection on native 4–12% polyacrylamide gels. LDL subclasses were analyzed by Lipoprint-LDL.

Results

Neonates show the expected lower content of apoB LDL and small dense LDL is the predominant apoB containing particle: 67 ± 7%. However, only 1.5% is sdLDL by Lipoprint. Maternal serum contains a large proportion of apoB in smaller LDL, 47 ± 6% as compared to non-pregnant women, 6 ± 1%, p < 0.001.

Conclusions

Neonates show the expected lower content of apoB–LDL but in an inverse distribution; sdLDL being the predominant particle. This novel finding for apoB sdLDL is consistent with previous data on HPLC studies showing increased middle and small-sized LDL lipid content in neonates as compared to adults which amounts to 84% of total LDL. Comparison of the results with Lipoprint LDL (lipids) with gradient gel electrophoresis native western blot (apoB-100) suggests that neonates carry fractions of small LDL that are comparatively poor in lipids as compared with their mothers. Further studies are warranted on the issue of sdLDL in neonates.     

Characteristics of KPC-2–producing Klebsiella pneumoniae (ST258) clinical isolates from outbreaks in 2 Mexican medical centers

The KPC-producing Klebsiella pneumoniae sequence type 258 (ST258) is an important pathogen widely spread in nosocomial infections. In this study, we identified the KPC-2–producing K. pneumoniae clinical isolates of 2 unrelated outbreaks that corresponded to pandemic strain ST258. The isolates showed high resistance to cephalosporins, carbapenems, quinolones, and colistin. The KPC-2–producing K. pneumoniae isolates were compared to the previously studied KPC-3–producing K. pneumoniae isolates from an outbreak in Mexico; they showed an unrelated pulsed-field gel electrophoresis fingerprinting pattern and a different plasmid profile. The KPC-2 carbapenemase gene was identified in two 230- and 270-kb non-conjugative plasmids; however, 1 isolate transferred the KPC-2 gene onto an 80-kb plasmid. These findings endorse the need of carrying out a continuous molecular epidemiological surveillance of carbapenem-resistant isolates in hospitals in Mexico.     

Comparison of Physical Activity Using Questionnaires (Leisure Time Physical Activity Instrument and Physical Activity at Home and Work Instrument) and Accelerometry in Fibromyalgia Patients: The Al-Ándalus Project

Objective

To compare the levels of physical activity (PA) assessed with questionnaires (Leisure Time Physical Activity Instrument [LTPAI], Physical Activity at Home and Work Instrument [PAHWI]) and accelerometry in patients with fibromyalgia; and to analyze the test-retest reliability of these questionnaires.

Design

Cross-sectional study.

Setting

Local fibromyalgia association.

Participants

Participants (N=99; 5 men) with fibromyalgia with a mean age of 50.2±9.5 years.

Interventions

Not applicable.

Main Outcome Measures

Participants carried an accelerometer for 1 week and completed the LTPAI and PAHWI twice (separated by a 1-wk interval). The LTPAI and PAHWI were summed to obtain overall values of PA.

Results

Time spent in total, moderate, and moderate-vigorous PA was higher (P<.01) when assessed by the LTPAI and PAHWI compared with accelerometry. The Bland-Altman method showed an absence of agreement between the LTPAI and PAHWI and the accelerometer for moderate, moderate-vigorous, and total PA. The test-retest reliability for the workplace subscale and total score of the PAHWI showed high and moderate intraclass correlation coefficients (ICCs), respectively, but also manifested high SE of measurements (up to 179min/d). The LTPAI showed low to moderate ICCs and high SE of measurements (up to 79min/d). For the LTPAI and PAHWI, the ICCs for total activity across the population were low to moderate, and the Bland-Altman method confirmed this lack of agreement.

Conclusions

The LTPAI and PAHWI and the accelerometer differ greatly when assessing PA. Furthermore, the LTPAI and PAHWI did not show good levels of test-retest reliability. Therefore, the self-administered LTPAI and PAHWI show questionable usefulness to assess PA in populations with fibromyalgia.     

Phenothiazines induce PP2A-mediated apoptosis in T cell acute lymphoblastic leukemia

T cell acute lymphoblastic leukemia (T-ALL) is an aggressive cancer that is frequently associated with activating mutations in NOTCH1 and dysregulation of MYC. Here, we performed 2 complementary screens to identify FDA-approved drugs and drug-like small molecules with activity against T-ALL. We developed a zebrafish system to screen small molecules for toxic activity toward MYC-overexpressing thymocytes and used a human T-ALL cell line to screen for small molecules that synergize with Notch inhibitors. We identified the antipsychotic drug perphenazine in both screens due to its ability to induce apoptosis in fish, mouse, and human T-ALL cells. Using ligand-affinity chromatography coupled with mass spectrometry, we identified protein phosphatase 2A (PP2A) as a perphenazine target. T-ALL cell lines treated with perphenazine exhibited rapid dephosphorylation of multiple PP2A substrates and subsequent apoptosis. Moreover, shRNA knockdown of specific PP2A subunits attenuated perphenazine activity, indicating that PP2A mediates the drug’s antileukemic activity. Finally, human T-ALLs treated with perphenazine exhibited suppressed cell growth and dephosphorylation of PP2A targets in vitro and in vivo. Our findings provide a mechanistic explanation for the recurring identification of phenothiazines as a class of drugs with anticancer effects. Furthermore, these data suggest that pharmacologic PP2A activation in T-ALL and other cancers driven by hyperphosphorylated PP2A substrates has therapeutic potential.     

Dysuria,heat stress,and muscle injury among Nicaraguan sugarcane workers at risk for Mesoamerican nephropathy

Objectives:Nicaraguan sugarcane workers, particularly cane cutters, have an elevated prevalence of chronic kidney disease of unknown origin, also referred to as Mesoamerican nephropathy (MeN). The pathogenesis of MeN may include recurrent heat stress, crystalluria, and muscle injury with subsequent kidney injury. Yet, studies examining the frequency of such events in long-term, longitudinal studies are limited.Methods:Using employment and medical data for male workers at a Nicaraguan sugarcane company, we classified months of active work as either work as a cane cutter or other sugarcane job and determined occurrence of dysuria, heat events and muscle events. Work months and events occurred January 1997 to June 2010. Associations between cane cutting and each outcome were analyzed using logistic regression based on generalized estimating equations for repeated events, controlling for age.Results:Among 242 workers with 7257 active work months, 19.5% of person-months were as a cane cutter. There were 160, 21, and 16 episodes of dysuria, heat events, and muscle events, respectively. Compared with work months in other jobs, cane cutting was associated with an elevated odds of dysuria [odds ratio 2.40 (95% confidence interval 1.56–3.68)]. The number of heat and muscle events by cane cutter and other job were limited.Conclusions:Working as a cane cutter compared with other jobs in the sugarcane industry was associated with increased dysuria, supporting the hypothesis that cane cutters are at increased risk of events suspected of inducing or presaging clinically evident kidney injury.