Detection of anti-ENA antibodies (Ab) in systemic lupus erythematosus (SLE): advantages of supplementing countercurrent immunoelectrophoresis with Western blotting (WB)

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Statistical power considerations in genotype-based recall randomized controlled trials

Randomized controlled trials (RCT) are often underpowered for validating gene-treatment interactions. Using published data from the Diabetes Prevention Program (DPP), we examined power in conventional and genotype-based recall (GBR) trials. We calculated sample size and statistical power for genemetformin interactions (vs. placebo) using incidence rates, gene-drug interaction effect estimates and allele frequencies reported in the DPP for the rs8065082 SLC47A1 variant, a metformin transported encoding locus. We then calculated statistical power for interactions between genetic risk scores (GRS), metformin treatment and intensive lifestyle intervention (ILI) given a range of sampling frames, clinical trial sample sizes, interaction effect estimates, and allele frequencies; outcomes were type 2 diabetes incidence (time-to-event) and change in small LDL particles (continuous outcome). Thereafter, we compared two recruitment frameworks: GBR (participants recruited from the extremes of a GRS distribution) and conventional sampling (participants recruited without explicit emphasis on genetic characteristics). We further examined the influence of outcome measurement error on statistical power. Under most simulated scenarios, GBR trials have substantially higher power to observe gene-drug and gene-lifestyle interactions than same-sized conventional RCTs. GBR trials are becoming popular for validation of gene-treatment interactions; our analyses illustrate the strengths and weaknesses of this design

Surgical management of BPH in Ghana: A need to improve access to transurethral resection of the prostate

Background: Open prostatectomy for benign prostate hyperplasia (BPH) is widely practiced in Ghana and Africa. Some of the reasons include lack of expertise and facilities for Transurethral Resection of the Prostate (TURP) and digital rectal examination assessment of prostates as greater than 50 grams.Objectives: To assess the prostate volumes of patients for surgical management of BPH by transrectal ultrasound (TRUS) and to determine, on the basis of prostatic volume, what percentage of those who had open prostatectomy could have been managed by TURP.Design: Prospective cohort study.Setting: The Korle Bu Teaching Hospital, Accra, Ghana.Subjects: Patients for elective surgical management of BPH from March to September 2010 were studied.Results: Fifty-eight patients had surgical management of BPH. Forty-six of them (79.3%) had open prostatectomy whilst twelve (20.7%) had TURP with a mean age of 70.4 and 65.2 years respectively. The most common reason for the open prostatectomy was refractory retention of urine (76.0%) while that for TURP was lower urinary tract symptoms (58.3%). The mean prostate volume for the patients who had open prostatectomy was 64.2ml ±28.7mls (range 23.0-121.0ml) while that of the TURP group was 40.1g±16.2mls (range18.5-70.0mls). Of the open prostatectomy group, 67.4% of them had prostate volumes 75mls or less. The blood transfusion and peri-operative complication rates for the open prostatectomy and TURP groups were 13% versus 8.3% and 8.7% versus 8.3% respectively. There was no mortality.Conclusion: Access to TURP in the surgical management of BPH in Ghana is low (20.7%). With improved facilities including routine use of TRUS for assessing prostate size and availability of expertise for TURP, 67.4% of patients offered open prostatectomy presently could benefit from TURP, using prostate volumes 75mls (75g) or less as indication for TURP

CD4 + Cell Response to Anti-Retroviral Therapy (ARTS) In Routine Clinical Care Over One Year Period in a Cohort of HAART Naive, HIV Positive Kenyan Patients

Background: Untreated HIV/AIDS leads to severe immune depletion with opportunistic                                                                    infections and other co-morbidities. Highly active anti-retroviral therapy (HAART) enhances immunity by sustained HIV- viral suppression, increase in CD4+ cell count and immune restoration. HAART reduces risk of neutropaenia, anaemia and accompanied decrease in incidence of opportunistic infections.Objectives: To study the CD4+ cell response in patients with severe HIV/AIDS disease over one year period while on HAART.Design: Observational, descriptive, longitudinal study.Setting: Kisumu District Hospital (Medical outpatient clinic, medical and surgical wards), Nairobi Rhematology clinic and The Mater Hospital between July 2001 and March 2007.Subjects: Four hundred and sixty three consenting patients were screened for the study.Intervention: The 103 patients included received HAART within one to four weeks and appropriate treatment for the opportunistic infections and other co-morbidities. Various HAART combinations including combivir/efavirenz, stavudine/lamivudine/nevirapine and triomune 30/40 (fixed dose combination of stavudine, nevirapine and lamivudine) were used. Some delayed HAART because of the co- morbidities which had to be managed first (severe anaemia, hepatitis and meningitis).Main outcome measures: CD4+ cell increase, new clinical events.Results: Four hundred and sixty three patients (256 males and 207 females) were screened. One hundred and three patients (55 males and 48 females) were included and 360 (201 males and 159 females) patients were excluded. Mean age was 37.9 ± 9.0 years range of (15-70). The mean CD4+ cell counts over the study period were 141.7 ± 176.5 (1-1022), 192.4 ± 198.5 (3-1275), 221.2 ± 178.0 (3-1300), 247.2 ± 197.7 (1-1401) and 268.6 ± 189.9 (1-1390) cells/µl at 0,3,6,9 and 12 months respectively. Nine patients had higher CD4+ cell counts > 350 cells/µl (433-1022) at baseline and higher HIV-viral RNA range between  51,830-1million copies/µl. The patients had multiple co-morbidities,namely, had tuberculosis, sepsis, cryptococcus meningitis, herpes zoster virus, four had non- Hodgkinfs lymphoma, oral candidiasis, hepatitis B virus, pneumocytis jiroveci pneumonia and HIV with renal dysfunction. Seventy (68%) patients had . 2 opportunistic infections. Mean AST, ALT and haemoglobin levels were 127.8 ± 79.8 IU/L, 157.2 ± 50.1 IU/L and 9.1 ± 4.3 g/dl respectively. No patient tested positive foranti-HCV antibodies.Conclusion: The majority of patients had advanced HIV infection at baseline. There was a slow but steady increase in CD4+ cell count over one year. However only 30(29.1%) of patients achieved immune restoration. Seventy three (70.9%) of patients still had immune depletion with low CD4+ cell counts at one year of receiving HAART. Patients with low CD4 + cell counts at baseline had a steady increase of CD4+ cells over the first six months and this emphasises the need to initiate HAART early in public health policy strategy. Expedited HAART initiation should be done in  patients with CD4+ cell counts < 350 cells/µl. Delayed HAART, at low CD4+ cell counts, is associated with poor immune recovery/restoration

Performance of the CMS Cathode Strip Chambers with Cosmic Rays

The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum