Microwave Components with MEMS Switches

RF MEMS switches with metal-metal contacts are being developed for microwave applications where broadband, high linearity performance is required. These switches provide less than 0.2 dB insertion loss through 40 GHz. This paper describes the integration of these switches into selected microwave components such as reconfigurable antenna elements, tunable filters, switched delay lines, and SPDT switches. Microwave and millimeter wave measured results from these circuits are presented

Rituximab Maintenance for the Treatment of Patients With Follicular Lymphoma: Systematic Review and Meta-analysis of Randomized Trials

Background Follicular lymphoma is characterized by slow growth and an initially high rate of response to treatment, but patients typically relapse and experience progressive disease. Rituximab in combination with chemotherapy has been shown to improve overall survival in patients with follicular lymphoma compared with chemotherapy alone, but data from randomized clinical trials evaluating rituximab maintenance treatment in these patients are limited. We aimed to evaluate the effect of maintenance treatment with rituximab on the overall survival of patients with follicular lymphoma. Methods We performed a systematic review and meta-analysis of randomized controlled trials that compared rituximab maintenance therapy with observation or treatment at relapse (no maintenance therapy). We searched The Cochrane Library, PubMed, EMBASE, LILACS, conference proceedings, databases of ongoing trials, and references of published trials. Two reviewers independently assessed the quality of the trials and extracted data. Hazard ratios for time-to-event data were estimated and pooled. Results Five trials including 1143 adult patients were included in this meta-analysis. Data for 985 patients with follicular lymphoma were available for the meta-analysis of overall survival. Patients treated with maintenance rituximab had statistically significantly better overall survival than patients in the observation arm or patients treated at relapse (hazard ratio [HR] for death = 0.60, 95% confidence interval [CI] = 0.45 to 0.79). The rate of infection-related adverse events was higher with rituximab maintenance treatment (HR = 1.99, 95% CI = 1.21 to 3.27). Patients with refractory or relapsed (ie, previously treated) follicular lymphoma had a survival benefit with maintenance rituximab therapy (HR for death = 0.58, 95% CI = 0.42 to 0.79), whereas previously untreated patients did not (HR for death = 0.68, 95% CI = 0.37 to 1.25). Conclusions These results suggest that maintenance therapy with rituximab, either as four weekly infusions every 6 months or as a single infusion every 2-3 months, should be added to standard therapy for patients with relapsed or refractory (ie, previously treated) follicular lymphoma after successful induction therapy. The higher rate of infections with rituximab therapy should be taken into consideration when making treatment decision

On the spread of epidemics in a closed heterogeneous population

Heterogeneity is an important property of any population experiencing a disease. Here we apply general methods of the theory of heterogeneous populations to the simplest mathematical models in epidemiology. In particular, an SIR (susceptible-infective-removed) model is formulated and analyzed for different sources of heterogeneity. It is shown that a heterogeneous model can be reduced to a homogeneous model with a nonlinear transmission function, which is given in explicit form. The widely used power transmission function is deduced from a heterogeneous model with the initial gamma-distribution of the disease parameters. Therefore, a mechanistic derivation of the phenomenological model, which mimics reality very well, is provided. The equation for the final size of an epidemic for an arbitrary initial distribution is found. The implications of population heterogeneity are discussed, in particular, it is pointed out that usual moment-closure methods can lead to erroneous conclusions if applied for the study of the long-term behavior of the model.Comment: 23 pages, 2 figure

Estimation of Breed Composition, Breed Heterosis and Epistatic Loss for Percent of Live Spermatozoa in Admixed Swiss Fleckvieh Bulls

The objective of this study was to estimate non-additive genetic effects of heterosis and epistatic loss on percent of live spermatozoa in admixed Swiss Fleckvieh bulls, a composite of Simmental and Holstein Friesian cattle. Heterosis is the additional gain in productivity or fitness of crossbred progeny over the mid purebred parents mean which arises from intra-locus gene interaction. Epistatic effects generally reduce productivity or fitness due to lack of gene interactions of genes from different breeds, which is called epistatic loss. Bovine SNP chip data of were used to predict locus specific breed origin of alleles along the autosomes of 815 admixed bulls as well as 147 Holstein Friesian and 207 Simmental bulls representing the parental breeds. The breed proportions for admixed bulls based on 32,899 SNP were used to calculate breed heterozygosity and epistatic loss, considering additive by additive effects for 1,000,000 random pairs of loci. The average Holstein Friesian ancestry in admixed bulls was estimated to be 0.82. Results of fitting different linear mixed models showed that including breed heterozygosity and epistatic loss improved the model fitness (ΔAIC > 3). The heterosis effect and epistatic loss were estimated 2.5(±1.39) % and -0.65(±1.68) % of live spermatozoa, respectively. High correlation (0.97) between breed heterozygosity and epistatic loss values indicate strong confounding of these effects in the model, indicating that it is not possible to properly separate these effects

Rituximab Maintenance for the Treatment of Patients With Follicular Lymphoma: An Updated Systematic Review and Meta-analysis of Randomized Trials

In a previous systematic review and meta-analysis of five randomized controlled trials comparing rituximab maintenance with no maintenance (observation or rituximab at progression) for patients with follicular lymphoma, we reported that rituximab maintenance treatment improved the overall survival of patients. In this study, we did a similar search of the electronic databases updated through December 31, 2010, and included nine trials and 2586 follicular lymphoma patients. Hazard ratios (HRs) for time-to-event data were estimated and pooled using the inverse variance method. Risk ratios for dichotomous data were pooled using a fixed effect model. Patients treated with rituximab maintenance had improved overall survival (pooled HR of death = 0.76, 95% confidence interval [CI] = 0.62 to 0.92) compared with patients in the no maintenance group. Patients with refractory or relapsed (ie, previously treated) follicular lymphoma treated with rituximab maintenance had improved overall survival (pooled HR of death = 0.72, 95% CI = 0.57 to 0.91), whereas previously untreated patients had no survival benefit (pooled HR of death = 0.86, 95% CI = 0.60 to 1.25). The rate of infection-related adverse events was higher in the rituximab maintenance group (pooled risk ratio = 1.67, 95% CI = 1.40 to 2.00). These results further support the use of rituximab maintenance in the standard of care for refractory or relapsed follicular lymphom

Saturable metabolism of continuous high-dose ifosfamide with Mesna and GM-CSF: A pharmacokinetic study in advanced sarcoma patients

Background: The aim of this study was to assess the pharmacology, toxicity and activity of high-dose ifosfamide/mesna ± GM-CSF administered by a five-day continuous infusion at a total ifosfamide dose of 12-18 g/m2 in adult patients with advanced sarcomas. Patients and methods: Between January 1991 and October 1992 32 patients with advanced or metastatic sarcoma were entered the study. Twenty-seven patients were pretreated including twenty-three with prior ifosfamide at less than 8 g/m2 total dose/cycle. In 25 patients (27 cycles) extensive pharmacokinetic analyses were performed. Results: The area under the plasma concentration-time curve (AUC) for ifosfamide increased linearly with dose while the AUC's of the metabolites measured in plasma by thin-layer chromatography did not increase with dose, particularly that of the active metabolite isophosphoramide mustard. Furthermore the AUC of the inactive carboxymetabolite did not increase with dose. Interpatient variability of pharmacokinetic parameters was high. Dose-limiting toxicity was myelosup-pression at 18 g/m2 total dose with grade 4 neutropenia in five of six patients and grade 4 thrombocytopenia in four of six patients. Therefore the maximum tolerated dose was considered to be 18 g/m2 total dose. There was one CR and eleven PR in twenty-nine evaluable patients (overall response rate 41%). Conclusion: Both the activation and inactivation pathways of ifosfamide are non-linear and saturable at high-doses although the pharmacokinetics of the parent drug itself are dose linear. Ifosfamide doses greater than 14-16 g/m2 per cycle appear to result in a relative decrease of the active metabolite isophosphoramide mustard. These data suggest a dose-dependent saturation or even inhibition of ifosfamide metabolism by increasing high dose ifosfamide and suggest the need for further metabolic studie

Homeopathic treatment of children with attention deficit hyperactivity disorder: a randomised, double blind, placebo controlled crossover trial

An increasing number of parents turn to homeopathy for treatment of their hyperactive child. Two publications, a randomised, partially blinded trial and a clinical observation study, conclude that homeopathy has positive effects in patients with attention deficit hyperactivity disorder (ADHD). The aim of this study was to obtain scientific evidence of the effectiveness of homeopathy in ADHD. A total of 83 children aged 6-16 years, with ADHD diagnosed using the Diagnostic and Statistical Manual of Mental Disorders-IV criteria, were recruited. Prior to the randomised, double blind, placebo controlled crossover study, they were treated with individually prescribed homeopathic medications. 62 patients, who achieved an improvement of 50% in the Conners' Global Index (CGI), participated in the trial. Thirteen patients did not fulfill this eligibility criterion (CGI). The responders were split into two groups and received either verum for 6 weeks followed by placebo for 6 weeks (arm A), or vice-versa (arm B). At the beginning of the trial and after each crossover period, parents reported the CGI and patients underwent neuropsychological testing. The CGI rating was evaluated again at the end of each crossover period and twice in long-term follow-up. At entry to the crossover trial, cognitive performance such as visual global perception , impulsivity and divided attention, had improved significantly under open label treatment ( P<0.0001). During the crossover trial, CGI parent-ratings were significantly lower under verum (average 1.67 points) than under placebo ( P =0.0479). Long-term CGI improvement reached 12 points (63%, P <0.0001). Conclusion:The trial suggests scientific evidence of the effectiveness of homeopathy in the treatment of attention deficit hyperactivity disorder, particularly in the areas of behavioural and cognitive function

Reduced dose of subcutaneous cladribine induces identical response rates but decreased toxicity in pretreated chronic lymphocytic leukaemia

Purpose To study the efficacy and the safety of cladribine (2-chlorodeoxyadenosine, 2-CDA) administered as 24-hour infusions or as subcutaneous bolus injections at two different doses to patients with relapsing or refractory chronic lymphocytic leukaemia (CLL). Patients and methods In this non randomised 2-cohort study, 20 patients with pretreated CLL received cladribine at a dose of 0.7 mg/kg/cycle as continuous i.v. infusions over seven days (group 1) and 35 patients were treated at a reduced dose of 0.5 mg/kg/cycle given as s.c. bolus injections for five days (group 2). After two cycles of four week duration, response was assessed. In the case of progressive disease, therapy was discontinued, otherwise a maximum of four additional cycles were administered until best response. Results A total of 130 cycles were administered (group 1: 41, group 2: 89). Patient characteristics in both groups were comparable. The median dose intensities were 0.172 mg/kg per week and 0.123 mg/kg per week for groups 1 and 2, respectively (P ≤ 0.0001). The overall response rate for all 55 patients was 38% (95% confidence interval (95% CI): 25%-52%), with 5% CR and 33% PR. Response was similar in both patient groups (35% in group 1, 40% in group 2). No association between cladribine dose intensity and response rate was found, and there was no difference between patients relapsing after or refractory to previous therapies (11 of 24 vs. 10 of 31). Median remission duration was six months in both groups. Toxicity, in particular infections (all WHO grades, 34% in group 1 versus 7% in group 2) and myelosuppression (grade 1-4 neutropenia, 72% versus 41% of cladribine cycles) were statistically significantly more frequent in group 1. Conclusion Cladribine is active in heavily pretreated patients with chronic lymphocytic leukaemias. Dose reduction by 29% led to similar response and remission duration, but to a significant decrease of myelotoxicity and risk of infection. Cladribine administered as s.c. bolus injections at 0.5 mg/kg per cycle is safe and this dose level should not be exceeded in this patient populatio