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Channel codes such as Low-Density Parity-Check (LDPC) codes may be employed in wireless transmission schemes for correcting transmission errors. This tolerance to channel- induced transmission errors allows reduced transmission energies to be used, at the cost of the additional signal processing energy dissipation of the LDPC decoder. To strike a trade-off, clock scaling may be employed for reducing the LDPC decoder’s energy dissipation, but at the cost of potentially introducing timing errors. Only a few previous attempts have been made to mitigate the occurrence of timing errors in channel decoders, by employing additional circuitry for detecting and correcting these clock- scaling-induced timing errors. In this paper, we demonstrate that stochastic LDPC decoders are capable of exploiting their inherent error correction capability fo...
Approximately 25% of polymorphonuclear leukocytes (PMNL) circulate in heterotypic complexes with one or more activated platelets. These platelet–neutrophil complexes (PNC) require platelet CD62P expression for their formation and represent activated subpopulations of both cell types. In this study, we have investigated the presence, time course, and mechanisms of PNC formation in 32 cases of severe pediatric meningococcal disease (MD) requiring intensive care.
There were marked early increases in PMNL CD11b/CD18 expression and activation, and reduced CD62L expression compared with intensive care unit control cases. Minimal platelet expression of the active form of IIbß3 (GpIIb/IIIa) was seen. PNC were reduced on presentation and fell to very low levels after 24 h. Immunostaining of skin biopsies demonstrated that PNC appear outside t...
Objective: Meningococcal disease causes septic shock with associated disseminated intravascular coagulation and hemorrhagic skin necrosis. In severe cases, widespread vascular thrombosis leads to gangrene of limbs and digits and contributes to morbidity and mortality. Uncontrolled case reports have suggested that thrombolytic therapy may prevent some complications, and the use of tissue plasminogen activator (t-PA) has been widespread. Our aim was to summarize the clinical outcome and adverse effects where systemic t-PA has been used to treat children with fulminant meningococcemia.
Design: International, multiple-center, retrospective, observational case note study between January 1992 and June 2000.
Setting: Twenty-four different hospitals in seven European countries and Australia.
Patients: A total of 62 consecutive infants and c...
An adverse prenatal environment may induce long-term metabolic consequences, in particular obesity and insulin resistance. Although the mechanisms are unclear, this programming has generally been considered an irreversible change in developmental trajectory. Adult offspring of rats subjected to undernutrition during pregnancy develop obesity, hyperinsulinemia, and hyperleptinemia, especially in the presence of a high-fat diet.
Reduced locomotor activity and hyperphagia contribute to the increased fat mass. Using this model of maternal undernutrition, we investigated the effects of neonatal leptin treatment on the metabolic phenotype of adult female offspring. Leptin treatment (rec-rat leptin, 2.5 µg/g·d, sc) from postnatal d 3–13 resulted in a transient slowing of neonatal weight gain, particularly in programmed offspring, and normal...
The discovery of a link between in utero experience and later metabolic and cardiovascular disease is one of the most important advances in epidemiology research of recent years. There is now increasing evidence that alterations in the fetal environment have long-term consequences on metabolic and endocrine pathophysiology in adult life. This process has been termed "fetal programming," and we have shown that undernutrition of the mother during gestation leads to obesity, hypertension, hyperphagia, hyperinsulinemia, and hyperleptinemia in offspring. Using this model of maternal undernutrition throughout pregnancy, we investigated whether prenatal influences may lead to alterations in postnatal locomotor behavior, independent of postnatal nutrition. Virgin Wistar rats were time mated and randomly assigned to receive food either ad libit...
Adult neurogenesis in the dentate gyrus is assuming an increasingly important role in supporting hippocampal-dependent learning and the modulation of mood and anxiety. Moreover, injury to the developing postnatal dentate gyrus has profound effects on neurogenesis and hippocampal learning throughout life. Organotypic hippocampal slice cultures represent an attractive model for studying neurogenesis both in the early postnatal and adult hippocampus, as they retain much of their anatomical and functional circuitry in vitro. Ongoing neurogenesis has been recently demonstrated in organotypic hippocampal slice cultures. However, cell proliferation, one of the critical components of neurogenesis, has yet to be characterized in this culture system. We examined single-pulse S-phase bromo-deoxyuridine (BrdU) labeling in the dentate granule layer...
Red hair in humans is associated with variant alleles of the MSH receptor gene, MC1R. Loss of MC1R function in other mammals results in red or yellow hair pigmentation. We show that a mouse bacterial artificial chromosome (BAC) which contains Mc1r will efficiently rescue loss of Mc1r in transgenic mice, and that overexpression of the receptor suppresses the effect of the endogenous antagonist, agouti protein. We engineered the BAC to replace the mouse coding region with the human MC1R sequence and used this in the transgenic assay. The human receptor also efficiently rescued Mc1r deficiency, and in addition, appeared to be completely resistant to the effects of agouti, suggesting agouti protein may not play a role in human pigmentary variation. Three human variant alleles account for 60% of all cases of red hair. We engineered each of ...
Background: Cognitive—behavioural therapy (CBT) improves persistent psychotic symptoms.
Aims: To test the effectiveness of added CBT in accelerating remission from acute psychotic symptoms in early schizophrenia.
Method: A 5-week CBT programme plus routine care was compared with supportive counselling plus routine care and routine care alone in a multi-centre trial randomising 315 people with DSM—IV schizophrenia and related disorders in their first (83%) or second acute admission. Outcome assessments were blinded.
Results: Linear regression over 70 days showed predicted trends towards faster improvement in the CBT group.
Uncorrected univariate comparisons showed significant benefits at 4 but not 6 weeks for CBTv. routine care alone on Positive and Negative Syndrome Scale total and positive sub-scale scores and delusion score and b...
Neurological complications are common in sickle cell disease (SCD). However, it is often difficult to relate the clinical presentation to conventional neuroimaging, because subclinical infarction is common and stroke has been described in the absence of large-vessel disease. We studied 48 patients with SCD aged 4-34 (median 13) years with T2-weighted, diffusion and perfusion magnetic resonance imaging (MRI) and with MR angiography. Forty-four underwent transcranial Doppler (TCD). Abnormalities on perfusion imaging were seen in 25 cases, 24 of whom had been symptomatic. The remaining patient had evidence of executive dysfunction and reduced perfusion in the frontal lobes. The perfusion abnormality was larger than the area of infarction in 9 patients and was seen in an arterial distribution with no infarction in a further 9. In 3 patient...
