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111.
The Good Behavior Game (GBG), a method of teacher classroom behavior management, was tested in first- and second-grade classrooms in 19 Baltimore City Public Schools beginning in the 1985–1986 school year. The intervention was directed at the classroom as a whole to socialize children to the student role and reduce aggressive, disruptive behaviors, confirmed antecedents of a profile of externalizing problem outcomes. This article reports on the GBG impact on the courses and interrelationships among aggressive, disruptive behavior through middle school, risky sexual behaviors, and drug abuse and dependence disorders through ages 19–21. In five poor to lower-middle class, mainly African American urban areas, classrooms within matched schools were assigned randomly to either the GBG intervention or the control condition. Balanced assignment of children to classrooms was made, and teachers were randomly assigned to intervention or control. Analyses involved multilevel growth mixture modeling. By young adulthood, significant GBG impact was found in terms of reduced high-risk sexual behaviors and drug abuse and dependence disorders among males who in first grade and through middle school were more aggressive, disruptive. A replication with the next cohort of first-grade children with the same teachers occurred during the following school year, but with minimal teacher mentoring and monitoring. Findings were not significant but generally in the predicted direction. A universal classroom-based prevention intervention in first- and second-grade classrooms can reduce drug abuse and dependence disorders and risky sexual behaviors.  相似文献   
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Amyotrophic lateral sclerosis (ALS) is predominantly sporadic, but associated with heritable genetic mutations in 5–10% of cases, including those in Cu/Zn superoxide dismutase (SOD1). We previously showed that misfolding of SOD1 can be transmitted to endogenous human wild-type SOD1 (HuWtSOD1) in an intracellular compartment. Using NSC-34 motor neuron-like cells, we now demonstrate that misfolded mutant and HuWtSOD1 can traverse between cells via two nonexclusive mechanisms: protein aggregates released from dying cells and taken up by macropinocytosis, and exosomes secreted from living cells. Furthermore, once HuWtSOD1 propagation has been established, misfolding of HuWtSOD1 can be efficiently and repeatedly propagated between HEK293 cell cultures via conditioned media over multiple passages, and to cultured mouse primary spinal cord cells transgenically expressing HuWtSOD1, but not to cells derived from nontransgenic littermates. Conditioned media transmission of HuWtSOD1 misfolding in HEK293 cells is blocked by HuWtSOD1 siRNA knockdown, consistent with human SOD1 being a substrate for conversion, and attenuated by ultracentrifugation or incubation with SOD1 misfolding-specific antibodies, indicating a relatively massive transmission particle which possesses antibody-accessible SOD1. Finally, misfolded and protease-sensitive HuWtSOD1 comprises up to 4% of total SOD1 in spinal cords of patients with sporadic ALS (SALS). Propagation of HuWtSOD1 misfolding, and its subsequent cell-to-cell transmission, is thus a candidate process for the molecular pathogenesis of SALS, which may provide novel treatment and biomarker targets for this devastating disease.Amyotrophic lateral sclerosis (ALS) is a fatal neuromuscular condition that afflicts as many as 1 of 350 males and 420 females over the age of 18 (1). In ALS, degeneration of upper and lower motor neurons causes progressive muscle paralysis and spasticity, affecting mobility, speech, swallowing, and respiration (2). Half of affected individuals die within 3 y, and less than 20% survive for more than 5 y (3); 90–95% of ALS cases are sporadic (SALS) in which some apparently facilitating gene mutations, such as repeat expansions in the gene that encodes ataxin-2 (4), have been identified. The remaining 5–10% of ALS cases are familial (FALS) and predominantly associated with Mendelian-inherited mutations in the genes encoding Cu/Zn superoxide dismutase (SOD1), TAR-DNA–binding protein 43 (TDP-43), fused in sarcoma/translocated in liposarcoma (FUS/TLS), C9ORF72, and other genes (reviewed in ref. 3).Despite the profusion of functionally diverse genes implicated in FALS and SALS, clinical and pathological similarities between all forms of ALS suggest the existence of a common pathogenic pathway that could be united by a single gene/protein (5). One of the mechanisms by which a mutant or wild-type (WT) protein can dominate pathogenesis of phenotypically diverse diseases is by propagated protein misfolding, such as that underpinning the prion diseases, which has been increasingly implicated in other neurodegenerative and systemic disorders (6, 7). A role for propagated protein misfolding in ALS is supported by the prion-like spatiotemporal progression of disease through the neuroaxis (8, 9). However, given the disparity in protein inclusion pathology between subtypes of ALS, a single unifying prion-like protein that could explain such a progression remains obscure.Whereas it is generally accepted SOD1 is not found in large perikaryal cytoplasmic inclusions outside of SOD1 FALS cases, misfolded SOD1 has been increasingly identified in SALS and non-SOD1 FALS (5, 10, 11). Indeed, we have reported that misfolded human wild-type SOD1 (HuWtSOD1) can be detected by spinal cord immunohistochemistry (IHC) in FALS secondary to FUS mutation, and in SALS patients with cytosolic WT TDP-43 accumulation (11). Moreover, in cell models, overexpression of WTTDP-43, or expression of mutant FUS or TDP-43, is associated with HuWtSOD1 misfolding (11). Collectively, these data are consistent with SOD1 being a molecular common denominator for all types of ALS. Furthermore, prion-like activity has been described for the cell-to-cell transmission of misfolding of mutant SOD1 (12), and we have reported that mutant SOD1 can confer its misfold on HuWtSOD1 (13). However, mutant SOD1 cannot explain propagation in SALS.To test if HuWtSOD1 participates in cell-to-cell transmission of protein misfolding, we make use of previously developed mouse mAb probes for misfolded/oxidized SOD1, recognizing either full-length human mutant or WT SOD1, generated against regions that are antibody-inaccessible in natively folded SOD1 (1315). Misfolded SOD1 mAbs used in this work are 10E11C11 and 3H1, directed against an unstructured electrostatic loop [disease-specific epitope-2 (DSE2)], and 10C12, directed against a C-terminal dimer interface peptide in which the cysteine at position 146 is substituted by a cysteic acid residue to mimic oxidation of this residue (DSE1a) (13). The use of such antibody probes have enabled us to unambiguously determine the role of misfolded mutant G127X in the induced misfolding of HuWtSOD1, which upon misfolding acquires a marked increase in sensitivity to protease digestion, consistent with global loosening of structure (13). The finding that misfolded endogenous HuWtSOD1 was observed long after transfected G127X-SOD1 was degraded suggested that HuWtSOD1, once misfolded, is capable of triggering an intracellular propagated misfolding reaction (13). We now report for the first time that misfolded HuWtSOD1 can transit cell to cell both via exosomes, and release of protein aggregates and subsequent uptake in neuronal cells. In addition, misfolded HuWtSOD1 can sustain intercellular propagated misfolding in vitro and is detectable in the spinal cord of all ALS patients tested, regardless of the genetic etiology of the disease. Collectively, these data indicate that HuWtSOD1 is competent to participate in propagated misfolding, suggesting a common pathogenic mechanism linking FALS and SALS.  相似文献   
113.

Background

Musculoskeletal involvement in Morquio A syndrome (mucopolysaccharidosis IVA; MPS IVA) contributes significantly to morbidity and mortality. While the spinal manifestations of the disorder have received considerable attention in the literature, there have been few reported studies to date to guide the management of the orthopedic problems associated with the lower and upper extremities.

Purpose

The objective was to develop recommendations for the management of the extremities in patients with Morquio A syndrome.

Methods

A group of specialists in orthopedics, pediatrics and genetics with experience in the management of Morquio A patients convened to review and discuss current clinical practices and to develop preliminary recommendations. Evidence from the literature was retrieved. Recommendations were further refined until consensus was reached.

Results and conclusions

This present article provides a detailed review and discussion of the lower and upper extremity deformities in Morquio A syndrome and presents recommendations for the assessment and treatment of these complications. Key issues, including the importance of early diagnosis and the implications of medical therapy, are also addressed. The recommendations herein represent an attempt to develop a uniform and practical approach to managing patients with Morquio A syndrome and improving their outcomes.  相似文献   
114.
The Centers for Disease Control and Prevention recently established a new reference value (≥ 5 μg/dL) as the standard for identifying children with elevated blood lead levels (EBLs). At present, 535 000 US children aged 1 to 5 years (2.6%) are estimated to have EBLs according to the new standard, versus 0.8% according to the previous standard (≥ 10 μg/dL). Because EBLs signify the threshold for public health intervention, this new definition increases demands on lead poisoning prevention efforts. Primary prevention has been proven to reduce lead poisoning cases and is also cost effective; however, federal budget cuts threaten the existence of such programs. Protection for the highest-risk children necessitates a reinstatement of federal funding to previous levels.In May 2012, officials of the Centers for Disease Control and Prevention (CDC) announced that they had accepted the recommendations set forth by the Advisory Committee on Childhood Lead Poisoning Prevention (ACCLPP) for (1) the discontinuation of the term blood lead “level of concern,” to acknowledge that there is no safe level of lead exposure, and (2) the use of a new reference value for the identification of children with elevated blood lead levels (EBLs).1 The level of concern, previously defined as 10 micrograms of lead per deciliter of blood, was established by the CDC as the EBL that should initiate a public health response and had been previously unchanged since 1991.2 By contrast, the new reference value is 5 micrograms per deciliter.1 Figure 1 depicts the decline in CDC-recommended blood lead level (BLL) action levels, a drop of more than 90% over the past several decades.3,4 Regardless of the action level of the time, childhood EBLs have long been targeted for complete elimination.5–9Open in a separate windowFIGURE 1—Trends in Centers for Disease Control and Prevention’s childhood blood lead level of concern: United States, 1960–2014.  相似文献   
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Novel therapeutic strategies are needed in the fight against pancreatic cancer. We have previously documented the chemopreventive effect of MDC-22 in preclinical models of pancreatic cancer. In the present work, we examined the therapeutic effects of MDC-22 in patient-derived tumor xenografts (PDTXs) and in LSL-KrasG12D/+, LSL-Trp53R172H/+, Pdx1-Cre (KPC) genetically engineered mice, two complementary and clinically relevant animal models of pancreatic cancer. In addition, we evaluated whether MDC-22 could synergize with current chemotherapeutic drugs used in the clinic. MDC-22 reduced the growth of various human pancreatic cancer cell lines in a concentration-dependent manner. In vivo, MDC-22 strongly reduced patient-derived pancreatic tumor xenograft growth by 50%, and extended survival of LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx1-Cre (KPC) mice by over a month (5.3 months versus 7.0 months). In both models, MDC-22 inhibited EGFR activation and its downstream signals, including ERK and FAK phosphorylation. In human pancreatic cancer cell lines, MDC-22 enhanced the growth inhibitory effect of irinotecan, and to a lesser degree those of gemcitabine and nab-paclitaxel. Normal human pancreatic epithelial cells were more resistant to the cytotoxic effects of, both, MDC-22 alone or in combination with irinotecan, indicating selectivity. Furthermore, MDC-22 enhanced irinotecan''s effect on cell migration, in part, by inhibiting EGFR/FAK signaling. Collectively, our results indicate that MDC-22 is an effective anticancer drug in preclinical models of pancreatic cancer, and suggest that MDC-22 plus irinotecan as drug combination strategy for pancreatic cancer treatment, which warrants further evaluation.  相似文献   
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