EFFECT OF AMPHETAMINES ON SPEECH DEFECTS IN THE MENTALLY RETARDED

In a double-blind study, 106 mentally retarded patients with speech defects were given 15 mg. of d-Amphetamine daily, or a placebo, for a three-month period. Speech defect types were: Stuttering, immature production, oral inaccuracy, lisp, psychotic, mongoloid, aphasia, deafness, and cleft palate. Only the stutterers showed obvious improvement in comparison with the placebo group. Three severe, long-term stutterers showed such dramatic improvement that their whole course in life has been changed.     

Acute burn care

LEARNING OBJECTIVES: After studying this article and accompanying Supplemental Digital Content, the participant should be able to: 1. Explain current burn-prevention strategies and criteria for referral to a burn center. 2. Summarize the current advances made in the critical care of acute burn patients. 3. Outline the recent developments in burn depth assessment and burn wound dressing technology. 4. Describe the common psychosocial aspects of postburn rehabilitation. SUMMARY: Burn patients require interdisciplinary care in which the plastic surgeon plays a prominent role. Appropriate referral, assessment, treatment, and posttreatment supports are essential to achieving favorable outcomes following burn injury. The authors reviewed the current literature on epidemiology, prevention, referral criteria, critical care, wound assessment, wound dressings, and psychosocial aspects of burn injury. Recent advances in burn care are highlighted and have been made possible through ongoing collaborative epidemiologic, clinical, and basic biomedical research. A systematic interdisciplinary approach to the evaluation and treatment of acute burn injuries is pivotal to providing patients with the greatest chance of functional recovery. Plastic surgeons treating burn patients must remain current in a wide variety of areas, ranging from critical care to psychosocial rehabilitation.     

Perisomatic inhibition and cortical circuit dysfunction in schizophrenia

Deficits of cognitive control in schizophrenia are associated with altered gamma oscillations in the prefrontal cortex. Paralbumin basket interneurons, which innervate the perisomatic region of pyramidal neurons, appear to play a key role in generating cortical gamma oscillations. In the prefrontal cortex of subjects with schizophrenia, alterations are present in both pre- and post-synaptic markers of the strength of GABA inputs from parvalbumin basket neurons to pyramidal neurons. These alterations may contribute to the neural substrate for impaired gamma oscillations in schizophrenia.     

Attenuated neuroprotective effect of riboflavin under UV-B irradiation via miR-203/c-Jun signaling pathway in vivo and in vitro

Background

Riboflavin (RF) or vitamin B2 is known to have neuroprotective effects. In the present study, we report the attenuation of the neuroprotective effects of RF under UV-B irradiation. Preconditioning of UV-B irradiated riboflavin (UV-B-RF) showed attenuated neuroprotective effects compared to that of RF in SH-SY5Y neuroblostoma cell line and primary cortical neurons in vitro and a rat model of cerebral ischemia in vivo.

Results

Results indicated that RF pretreatment significantly inhibited cell death and reduced LDH secretion compared to that of the UV-B-RF pretreatment in primary cortical neuron cultures subjected to oxygen glucose deprivation in vitro and cortical brain tissue subjected to ischemic injury in vivo. Further mechanistic studies using cortical neuron cultures revealed that RF treatment induced increased miR-203 expression which in turn inhibited c-Jun expression and increased neuronal cell survival. Functional assays clearly demonstrated that the UV-B-RF preconditioning failed to sustain the increased expression of miR-203 and the decreased levels of c-Jun, mediating the neuroprotective effects of RF. UV-B irradiation attenuated the neuroprotective effects of RF through modulation of the miR-203/c-Jun signaling pathway.

Conclusion

Thus, the ability of UV-B to serve as a modulator of this neuroprotective signaling pathway warrants further studies into its role as a regulator of other cytoprotective/neuroprotective signaling pathways.     

Physiological methods to study biofilm disinfection

This report reviews the development of a rapidin situ approach to study the physiological responses of bacteria within biofilms to disinfectants. One method utilized direct viable counts (DVC) to assess the disinfection efficacy when thin biofilms were exposed to chlorine or monochloramine. Results obtained using the DVC method were one log higher than plate count (PC) estimates of the surviving population after disinfection. Other methods incorporated the use of fluorogenic stains, a cryotomy technique to yield thin (5-m) sections of biofilm communities and examination by fluorescence microscopy. The fluorogenic stains used in this approach included 5-cyano-2,3-ditolyl tetrazolium chloride (CTC), which indicates cellular electron transport activity and Rhodamine 123, which responds specifically to proton motive force. The use of these stains allowed the microscopic discrimination of physiologically active bacteria as well as heterogeneities of active cells within thicker biofilms. The results of experiments using these techniques with pure culture and binary population biofilms on stainless steel coupons indicated biocidal activity of chlorine-based disinfectants occurred initially at the bulk-fluid interface of the communities and progressed toward the substratum. This approach provided a unique opportunity to describe the spatial response of bacteria within biofilms to antimicrobial agents and address mechanisms explaining their comparative resistance to disinfection in a way that has not been possible using traditional approaches. Results obtained using this alternative approach were also consistently higher than PC data following disinfection. These observations suggest that traditional methods involving biofilm removal and bacterial enumeration by colony formation overestimate biocide efficacy. Hence the alternative approach described here more accurately indicates the ability of bacteria surviving disinfection to recover and grow as well as demonstrate spatial heterogeneities in cellular physiological activities within biofilms.     

Maxicircle DNA and edited mRNA sequences of closely related trypanosome species: implications of kRNA editing for evolution of maxicircle genomes.

kRNA editing produces functional mRNAs by uridine insertion and deletion. We analyzed portions of the apocytochrome b and NADH dehydrogenase subunits 7 and 8 (ND7 and 8) genes and their edited mRNAs in Trypanosoma congolense and compared these to the corresponding sequences in T.brucei. We find that these genes are highly diverged between the two species, especially in the positions of thymidines and in nucleotide transitions. Editing eliminates differences in encoded uridines producing edited mRNAs that are identical except for the nucleotide substitutions. The resulting predicted proteins are identical since all nucleotide substitutions are silent. A T.congolense minicircle-encoded gRNA which can specify editing of ND8 mRNA was identified. This gRNA can basepair with both T.congolense and T.brucei ND8 mRNA despite nucleotide transitions due to the flexibility of G:U base-pairing. These results illustrate how editing affects the characteristics of maxicircle sequence divergence and allows protein sequence conservation despite a level of DNA sequence divergence which would be predicted to be intolerable in the absence of editing.