Comparison of a transfusion preparation of newly formed red cells and standard washed red cell transfusions in patients with homozygous beta- thalassemia

BACKGROUND: Previous studies of transfusions of newly formed red cells (neocytes) demonstrated modest extensions of transfusion interval in patients with homozygous beta-thalassemia. STUDY DESIGN AND METHODS: The clinical benefits of a new system of neocyte preparation (Neocel, Cutter Biological, Berkeley, CA), reported to combine ease of preparation with reduction in the transfusion requirements of thalassemia patients, were evaluated. Sixteen thalassemic patients who had undergone splenectomy received eight consecutive, standard, automated, washed red cell transfusions (standard transfusions), followed by eight transfusions with the neocyte preparation (neocyte transfusions). In each arm of the study, mean pretransfusion hemoglobin and mean red cell mass transfused were carefully controlled and were similar. RESULTS: A significant (p < 0.0001) extension of transfusion interval was observed in patients receiving neocyte transfusions (mean +/− SD; 38.7 +/− 34 days; range, 35.0-44.5), over that in those receiving standard transfusions (32.9 +/− 2.5 days; range, 29.6-38.5). The mean prolongation of transfusion interval by neocyte transfusion corresponded to a mean reduction of 25 mL in packed red cells transfused per kg of body weight per patient per year and a mean reduction in transfused iron of 15 percent per year per patient. During neocyte transfusions, blood preparation costs were considerably increased and donor exposure was significantly (p < 0.0005) higher than during the standard transfusion period. CONCLUSION: These data demonstrate that extension of the transfusion interval, and reduction in transfused iron, may be achieved in thalassemic patients by use of the Neocel system. These benefits are achieved, however, with substantial increases in donor exposure and in component preparation costs.     

Clinical Assessment of a Novel Recombinant Simian Adenovirus ChAdOx1 as a Vectored Vaccine Expressing Conserved Influenza A Antigens

Adenoviruses are potent vectors for inducing and boosting cellular immunity to encoded recombinant antigens. However, the widespread seroprevalence of neutralizing antibodies to common human adenovirus serotypes limits their use. Simian adenoviruses do not suffer from the same drawbacks. We have constructed a replication-deficient chimpanzee adenovirus-vectored vaccine expressing the conserved influenza antigens, nucleoprotein (NP), and matrix protein 1 (M1). Here, we report safety and T-cell immunogenicity following vaccination with this novel recombinant simian adenovirus, ChAdOx1 NP+M1, in a first in human dose-escalation study using a 3+3 study design, followed by boosting with modified vaccinia virus Ankara expressing the same antigens in some volunteers. We demonstrate ChAdOx1 NP+M1 to be safe and immunogenic. ChAdOx1 is a promising vaccine vector that could be used to deliver vaccine antigens where strong cellular immune responses are required for protection.     

Coadministration of Seasonal Influenza Vaccine and MVA-NP+M1 Simultaneously Achieves Potent Humoral and Cell-Mediated Responses

Current seasonal influenza vaccines have reduced immunogenicity and are of suboptimal efficacy in older adults. We have previously shown that the novel candidate vaccine MVA-NP+M1 is able to boost memory T cell responses in adults aged 50–85 years. Preclinical studies have demonstrated that viral vectored vaccines can act as adjuvants when coadministered with protein-based vaccines. We have conducted a phase I clinical trial to compare the coadministration of seasonal influenza vaccine and MVA-NP+M1 with seasonal influenza vaccine alone in adults aged 50 years and above. This combination of vaccines was safe and well tolerated. T cell responses to internal influenza proteins were boosted to significantly higher levels in the group receiving MVA-NP+M1 compared with the group receiving seasonal influenza vaccine alone. Rates of seroprotection and seroconversion against the three vaccine strains were similar in both groups; however, there was a significant increase in the geometric mean titer ratio for the H3N2 component of seasonal influenza vaccine in the coadministration group. While some vaccine combinations result in immune interference, the coadministration of MVA-NP+M1 alongside seasonal influenza vaccine is shown here to increase some influenza strain-specific antibody responses and boost memory T cells capable of recognizing a range of influenza A subtypes.     

The impact of platelet membrane glycoprotein Ib alpha and Ia/IIa polymorphisms on the risk of thrombosis in the antiphospholipid syndrome

Background

Pathogenesis of thrombus formation in antiphospholipid syndrome (APS) is not clear. Platelet membrane glycoprotein (GP) receptors play important roles in development of thrombosis.

Objectives

We investigated the association between development of thrombosis in APS and polymorphisms of GPIb alpha variable number of tandem repeats (VNTR), Kozak, and GPIa C807T.Patients/MethodsSixty patients with APS (30 with proven thrombosis and 30 without thrombosis) and 63 controls were included. Presence of GPIa C807T polymorphism was determined with real-time PCR and GPIb alpha Kozak and VNTR polymorphisms by conventional PCR.

Results

Frequency of C807T TT genotype was significantly higher in APS with thrombosis than APS without thrombosis (p = 0.023) and also in APS with multiple thrombi compared to APS without thrombi (p = 0.023). Frequency of Kozak TC genotype was higher in APS with arterial thrombosis compared to APS with venous thrombosis, controls, and APS without thrombosis (p = 0.03, p = 0.0007, and p = 0.0024 respectively). D allele frequency and D allele carrier state for VNTR were significantly less in APS than controls (p = 0.0018 and p = 0.0046 respectively).

Conclusions

C807T TT genotype may confer a risk for thrombosis and Kozak TC genotype for arterial thrombosis. D allele of VNTR may protect from APS. No patients with C807T TT or Kozak TC genotypes carried the protective DD genotype of VNTR. These polymorphisms may increase risk for both arterial and venous thrombosis. The utility of prophylaxis with anti-platelet drugs in at least a subgroup of APS patients should be investigated with clinical trials.     

The origins of a research community in the Majengo observational cohort study,Nairobi, Kenya

Background  

Since the 1980s the Majengo Observational Cohort Study (MOCS) has examined sexually transmitted infections, in particular HIV/AIDS, in a cohort of sex workers in Majengo, an impoverished urban village in Nairobi, Kenya. The MOCS investigators have faced criticism since the women have remained in the sex trade for the duration of their participation in the study, prompting concerns about exploitation. Yet despite these concerns, the cohort has survived for almost 30 years.     

Accelerated hypofractionated adjuvant whole breast radiation with simultaneous integrated boost using volumetric modulated arc therapy for early breast cancer: A phase I/II dosimetric and clinical feasibility study from a tertiary cancer care centre of India

Background

Hypofractionation has become standard of care after Breast Conserving Therapy (BCT) in many European and few others western countries. Though still debatable, tumor cavity boost is routinely practised in our centre. Hypofractionation is not yet the current standard of practice in Asian countries. Employing hypofractionation and simultaneous integrated boost to lumpectomy cavity with conformal technique is not the current practice in this region. Hence the study was performed to see whether accelerated hypofractionation and simultaneous boost can be combined using volumetric modulated arc therapy (VMAT) in treating early breast cancer (EBC) patients.

Delayed diagnosis of anorectal malformations: are current guidelines sufficient?

Aim: To determine the frequency and presenting features of infants with delayed diagnosis of anorectal malformations (ARM) referred to an Australian tertiary paediatric institution. Methods: Infants referred to our institution with a final diagnosis of ARM were retrospectively reviewed between 2001 and 2009. The first cohort consisted of patients that were referred between November 2001 and November 2006 with the diagnosis of an ARM that had been delayed for more than 48 h. The second cohort was those referred between December 2006 and May 2009 with whom the diagnosis of ARM had not been made within 24 h of birth. Results: Nineteen infants were referred with delayed diagnosis of an ARM over the 7.5 years of the study. Of 44 patients referred to our institution between December 2006 and May 2009, diagnosis of an ARM was delayed more than 24 h in 14 (32%). There was no difference in gender, birth weight, prematurity, type of malformation or presence of associated anomalies between those with timely and delayed diagnosis of their ARM. A significantly greater proportion of those with a delayed diagnosis presented with obstructive symptoms (86% vs. 27%, P < 0.001), including abdominal distension (57%) and delayed passage of meconium or stool (29%). Despite undergoing neonatal examination, the diagnosis of ARM was missed in 12 patients overall. Conclusion: Delayed diagnosis of an ARM appears to be common, occurring in approximately 32% of patients referred to our institution over the last 2.5 years. Current guidelines appear insufficient to ensure prompt diagnosis of ARM.     

The Nigerian national blindness and visual impairment survey: Rationale, objectives and detailed methodology

Background

Despite having the largest population in Africa, Nigeria has no accurate population based data to plan and evaluate eye care services. A national survey was undertaken to estimate the prevalence and determine the major causes of blindness and low vision. This paper presents the detailed methodology used during the survey.

Methods

A nationally representative sample of persons aged 40 years and above was selected. Children aged 10–15 years and individuals aged <10 or 16–39 years with visual impairment were also included if they lived in households with an eligible adult. All participants had their height, weight, and blood pressure measured followed by assessment of presenting visual acuity, refractokeratomery, A-scan ultrasonography, visual fields and best corrected visual acuity. Anterior and posterior segments of each eye were examined with a torch and direct ophthalmoscope. Participants with visual acuity of < = 6/12 in one or both eyes underwent detailed examination including applanation tonometry, dilated slit lamp biomicroscopy, lens grading and fundus photography. All those who had undergone cataract surgery were refracted and best corrected vision recorded. Causes of visual impairment by eye and for the individual were determined using a clinical algorithm recommended by the World Health Organization. In addition, 1 in 7 adults also underwent a complete work up as described for those with vision < = 6/12 for constructing a normative data base for Nigerians.

Discussion

The field work for the study was completed in 30 months over the period 2005–2007 and covered 305 clusters across the entire country. Concurrently persons 40+ years were examined to form a normative data base. Analysis of the data is currently underway.

Conclusion

The methodology used was robust and adequate to provide estimates on the prevalence and causes of blindness in Nigeria. The survey would also provide information on barriers to accessing services, quality of life of visually impaired individuals and also provide normative data for Nigerian eyes.