Network efficient power control for wireless communication systems.

We introduce a two-loop power control that allows an efficient use of the overall power resources for commercial wireless networks based on cross-layer optimization. This approach maximizes the network's utility in the outer-loop as a function of the averaged signal to interference-plus-noise ratio (SINR) by considering adaptively the changes in the network characteristics. For this purpose, the concavity property of the utility function was verified with respect to the SINR, and an iterative search was proposed with guaranteed convergence. In addition, the outer-loop is in charge of selecting the detector that minimizes the overall power consumption (transmission and detection). Next the inner-loop implements a feedback power control in order to achieve the optimal SINR in the transmissions despite channel variations and roundtrip delays. In our proposal, the utility maximization process and detector selection and feedback power control are decoupled problems, and as a result, these strategies are implemented at two different time scales in the two-loop framework. Simulation results show that substantial utility gains may be achieved by improving the power management in the wireless network.

Natural killer cells and malignant haemopathies: a model for the interaction of cancer with innate immunity.

Despite recent progress in the therapeutic approach of malignant haemopathies, their prognoses remain frequently poor. Immunotherapy offers an alternative of great interest in this context but defect or abnormal expression of human leukocyte antigens (HLA), frequently observed in cancer cells, limits its efficiency. Natural killer (NK) cells, which are able to kill target cells in a HLA-independent way, represent a novel tool in the treatment of haematological malignancies. Abnormal NK cytolytic function is observed in all the haematological malignancies studied, such as acute leukaemia, myelodysplastic syndromes or chronic myeloid/lymphoid leukaemia. Several mechanisms are involved in the alterations of NK cytotoxicity: decreased expression of activating receptors, increased expression of inhibitory receptors or defective expression of NK ligands on target cells. Further studies are needed to identify how each type of haematological malignancy escapes from the innate immune response. Attempts to increase the expression of activating receptors, to counteract inhibitory receptors expression, or to increase NK cell cytotoxic capacities could overcome tumour escape from innate immunity. These therapies are based on monoclonal antibodies or culture of NK cells in presence of cytokines or dendritic cells. Moreover, many novel drugs used in haematological malignancies [tyrosine kinase inhibitors, IMIDs(®), proteasome inhibitors, demethylating agents, histone deacetylase inhibitors (HDACis), histamine dihydrochloride] display interesting immunomodulatory properties that affect NK cells. These data suggest that combined modalities associating cytotoxic drugs with innate immunity modulators may represent a major breakthrough in tumour eradication.

Smoking cessation counseling by resident physicians in internal medicine, family practice, and pediatrics.

Residents in primary care specialties care for many patients who smoke cigarettes, but little is known about their smoking cessation counseling (SCC). We surveyed 309 residents (72 family practice, 171 internal medicine, and 66 pediatrics residents) in 13 programs to determine their practices, knowledge, attitudes, and training in SCC. More than 90% thought physicians are responsible for SCC, the majority routinely took smoking histories, and 80% attempted to motivate patients to quit smoking. However, 25% or fewer reported discussing obstacles to quitting, setting a quit date, prescribing nicotine gum, scheduling follow-up visits, or providing self-help materials. Family practice residents used more SCC techniques (1.8) than did internal medicine (0.8) and pediatrics (0.1) residents. Only 54% of residents reported recent SCC training and 13% reported formal SCC training. Recent training correlated with the number of counseling techniques used. Residents in primary care specialties report positive attitudes but inadequate practice and training in SCC.

Manipulation of dopamine d1-like receptor activation in the rat medial prefrontal cortex alters stress- and cocaine-induced reinstatement of conditioned place preference behavior.

These studies examined the ability of the dopamine D1-like agonist SKF 81297 and D1-like antagonist SCH 23390 in the medial prefrontal cortex to alter the reinstatement of cocaine-induced conditioned place preference behavior. Male Sprague-Dawley rats were fitted with bilateral cannulae over the medial prefrontal cortex and subsequently trained in a conditioned place preference task. Animals were trained in this task using four pairings of cocaine (12 mg/kg, i.p.). Conditioned place preference was demonstrated in all animals, and this behavior was then extinguished over a 5-10-day period before testing for reinstatement. Just prior to reinstatement by immobilization stress or a cocaine priming injection (5 mg/kg, i.p.), a microinjection of the D1-like receptor antagonist SCH 23390 (0.01, 0.1 or 1.0 microg/side), or the D1-like receptor agonist SKF 81297 (0.1, 0.3 or 1.0 microg/side) was given into the medial prefrontal cortex. SCH 23390 blocked both stress- and cocaine-induced reinstatement of conditioned place preference after the two higher doses were administered into the medial prefrontal cortex. The highest dose of SKF 81297 (1.0 microg/side) prevented immobilization stress- but not cocaine-induced reinstatement. The highest dose of these drugs given in the absence of stress or cocaine did not produce reinstatement. The results indicate that immobilization stress given within the place-preference chamber is capable of producing reinstatement of cocaine-seeking behavior. The microinjection studies suggest that D1-like receptor antagonism within the prefrontal cortex is sufficient to block reinstatement by stress and cocaine. Furthermore, the results from D1-like receptor activation in the medial prefrontal cortex point to utilization of different neural pathways for stress- and cocaine-induced reinstatement.

The relationship between dietary intake of choline, choline serum levels, and cognitive function in healthy elderly persons.

This study was designed to obtain information on normal dietary intake and serum levels of choline in a healthy elderly population and to observe the relationship between blood levels of choline and cognitive function. Two hundred fifty-eight healthy volunteers with a mean age of 72 years were recruited, and blood samples and dietary histories were obtained. All subjects were ambulatory, living at home, free of serious medical illnesses, and taking no prescription medications. Cognitive abilities were assessed by the Halstead Category Test, a nonverbal test measuring abstract thinking, and the Wechsler Memory Scale, using the multiple scoring method, which measures both long- and short-term memory. The mean value for serum choline was 13.16 micron with a standard deviation of 3.31. Serum choline levels were found to increase with age, but no difference was found between serum choline levels for men and women. There was no association between dietary intake and serum choline levels, nor could a relationship be found between serum choline levels and cognitive function.

Conditioned fear stimuli reinstate cocaine-induced conditioned place preference.

These studies examined the ability of a conditioned stimulus previously paired with footshock to reinstate cocaine-induced conditioned place preference. Male rats were given either odor or tone in a paired (PRD group) or explicitly unpaired (random, RND group) manner with footshock. All rats were subsequently trained in a cocaine conditioned place preference (CPP) task. Cocaine CPP was demonstrated in all groups. After CPP extinction, presentation of the conditioned fear stimulus produced a greater degree of reinstatement in PRD rats compared to the RND group. This was true whether the conditioned stimulus was odor or tone, but when odor was used as the conditioned stimulus, the RND group also partially reinstated cocaine CPP. In rats trained with tone as the conditioned stimulus, presentation of the tone during the test for reinstatement produced robust reinstatement of cocaine CPP only in the PRD, but not RND, group. In contrast, a subsequent priming injection with cocaine reinstated cocaine CPP equally in both RND and PRD groups. These studies indicate for the first time that conditioned fear stimuli induce reinstatement of cocaine CPP, and suggest that stimuli associated with prior stress may produce relapse in humans.

Toxocariasis: a cause of hyper IgE and eosinophilia.

We present a patient with elevation of total serum IgE, eosinophilia and Toxocara exoantigen specific IgG and IgE antibodies (detected by ELISA and RAST, respectively). We ruled out atopy and other parasitic diseases common in our habitat (e.g., Echinococcus granulosus, Ascaris lumbricoides, Schistosoma mansoni). The patient was asymptomatic over the four years of the study, and the levels of total serum IgE, eosinophils and Toxocara exoantigen specific IgG and IgE remained high. Although at present, immunodiagnostic tests have a high sensitivity and specificity for toxocariasis, their value is limited. This is illustrated by the fact that in our patient these techniques could not distinguish between past and present infection.

A role for glycosylated serine-rich repeat proteins in gram-positive bacterial pathogenesis.

Bacterial attachment to host surfaces is a pivotal event in the biological and infectious processes of both commensal and pathogenic bacteria, respectively. Serine-rich repeat proteins (SRRPs) are a family of adhesins in Gram-positive bacteria that mediate attachment to a variety of host and bacterial surfaces. As such, they contribute towards a wide-range of diseases including sub-acute bacterial endocarditis, community-acquired pneumonia, and meningitis. SRRPs are unique in that they are glycosylated, require a non-canonical Sec-translocase for transport, and are largely composed of a domain containing hundreds of alternating serine residues. These serine-rich repeats are thought to extend a unique non-repeat (NR) domain outward away from the bacterial surface to mediate adhesion. So far, NR domains have been determined to bind to sialic acid moieties, keratins, or other NR domains of a similar SRRP. This review summarizes how this important family of bacterial adhesins mediates bacterial attachment to host and bacterial cells, contributes to disease pathogenesis, and might be targeted for pharmacological intervention or used as novel protective vaccine antigens. This review also highlights recent structural findings on the NR domains of these proteins.

[Gingival smile: surgical-orthodontic treatment]. / Sonrisa gingival: tratamiento ortodóncico-quirúrgico.

The treatment of patients with dentofacial deformities which include excessive exposure of frontal upper teeth and upper alveolar gum at resting and/or dynamic position of the lips, is a frequent challenge to odontologists, orthodontists, prosthesists and maxillofacial surgeons. This article introduces a joint orthodontic-surgical approach for the functional and esthetic correction of this deformity. Attained results are illustrated by two representative case histories.

Clindamycin vaginal cream vs oral metronidazole in the treatment of bacterial vaginosis.

PIP: This study was designed to compare the safety/efficacy of the treatment of 2% clindamycin vaginal cream and oral metronidazole in 184 women with bacterial vaginosis. This was a randomized, prospective, multicenter, double-blind, controlled study. Patients were randomized to either Clindamycin phosphate vaginal cream 2%, 5 gm intravaginally at bedtime, and placebo oral metronidazole capsules taken twice daily, or oral metronidazole capsules, 500 mg, taken twice daily, and placebo clindamycin vaginal cream, 5 gm to be administered intravaginally at bedtime. All treatments were for 7 days. Patients were seen for followup at 4-13 days and 20-43 days after completion of protocol therapy. 2 investigators in Mexico City enrolled a total of 184 patients (91 clindamycin and 93 metronidazole). 1 patient never received drugs after enrollment, leaving 183 valuable for safety. A total of 114 were valuable for efficacy. Protocol regimens were comparable in efficacy (p=0.22) and the percentage of cure/improvement was 87% in the clindamycin group compared to 79% in the metronidazole group. No relapse was observed in the clindamycin group, as opposed to 7% in the metronidazole group. The clindamycin group had a failure of 13% while this was 15% in the metronidazole group. Both treatments were well-tolerated. Most of the events were either vulvovaginal irritation upon application of the study drug, or the development of vaginitis/cervicitis. The 1 event classified as serious in this study (metronidazole group) was generalized rash which, in the opinion of the investigator, was related to the study drug. There were 4 nongenital tract side effects (1 gastrointestinal, 2 dermatologic, and 1 allergy) all in the metronidazole group. The authors can conclude that clindamycin 2% vaginal cream is at least as effective as orally administered metronidazole for the treatment of bacterial vaginosis in nonpregnant women.^ieng

Alcohol intake in a healthy elderly population.

The relationship between amount of alcohol consumption and social, psychological, and cognitive status was examined in 270 healthy, independently living men and women over age 65. Forty-eight per cent of the sample recorded some alcohol intake during a three-day diet record, with 8 per cent drinking 30 or more grams of alcohol daily. Alcohol intake was positively associated with male gender, income, and amount of education and negatively associated with age. Alcohol intake was not associated with any changes in social or psychological status, but was positively associated with several measurements of cognitive status. These correlations were weak, however, and tended to disappear after controlling for income, education, gender, and age. Past alcohol intake was not associated with any indicators of present social, psychological, or cognitive functioning.

[Diagnostic procedures in primary ciliary dyskinesia. The usefulness of nasal biopsy]. / Procedimientos diagnósticos en la discinesia ciliar primaria. Utilidad de la biopsia nasal.

Eight patients are studied who are suspected to have primary ciliary dyskinesia (PCD). All cases presented from the first year of live repetitive respiratory infections, chronic cough, mucopurulent rhinorrhea, radiologic signs of sinusitis and one patient also presented situs inversus. Bronchiectasis were found in four cases, they were discarded in two cases, and in two other cases they could not be found nor discarded. The definite diagnosis was achieved by the study of the ultrastructure of the cilia by nasal biopsy. In three cases, nasal biopsy discarded the diagnosis of PCD and confirmed such diagnosis in other three cases. One case of PCD was diagnosed by a bronchial biopsy after two unsuccessful attempts to obtain a nasal sample containing ciliary epithelium. One case remains undiagnosed since after a nonvalid biopsy, we did not consider necessary to obtain another one given that the patient was asymptomatic during the last three years.