A safety evaluation of drotrecogin alfa (activated) in hematopoietic stem cell transplant patients with severe sepsis: lessons in clinical research

We conducted an open-label, multicenter, single-arm clinical trial to investigate the safety and efficacy of drotrecogin alfa (activated) (Drot AA) in hematopoietic stem cell transplant (HSCT) patients with severe sepsis. Drot AA was administered as a continuous i.v. infusion of 24 microg/kg/h for 96 h. The target enrollment was 250 patients in 15-20 transplant centers over a 2-year period (March 2003-March 2005). However, after only 10 months, in December 2003, the trial was stopped due to a low enrollment of seven patients at three of the 15 sites that were open for accrual. Six of the seven patients completed the drug infusion. Two patients experienced serious bleeding events. The first patient developed a nonfatal diffuse alveolar hemorrhage 2 days after study-drug completion. The second patient had severe coagulopathy and developed a fatal intracranial hemorrhage on the third day of drug infusion. Three of the seven patients were alive 100 days after the HSCT. The slow enrollment rate was attributed to changes in transplant preparatory regimens, enhancements in antimicrobial prophylactic protocols and the use of antimicrobial-coated catheters. The small number of patients in this report precludes a definitive assessment of the safety and efficacy of Drot AA in HSCT patients.

Occurrence of Burkholderia cepacia in the hospital environment

AIM

To determine the prevalence of Burkholderia cepacia from the environment in a regional adult cystic fibrosis (CF) care centre.

METHODS

Two hundred and eighty-five environmental samples were taken from inpatient and outpatient environments within the CF centre. Following a non-selective enrichment step, broths were plated onto a selective medium and B. cepacia isolates were confirmed by phenotypic tests and also genotypically by species specific 16S rRNA PCR.

RESULTS

B. cepacia was not detected from commonly shared items of equipment, staff hands, staff uniforms or toilets. In addition, the organism was not detected in toilet bowls, even in the B. cepacia unit. With regard to positive environments for B. cepacia, 4/10 (40%) of the outside surfaces and inner rims of patients' plastic disposable sputum collection containers and 4/17 (23.5%) of air from patients' rooms, following physiotherapy, were positive.

CONCLUSIONS

All positive samples originated in the B. cepacia segregation area of the inpatient wards and B. cepacia was not detected in the non-cepacia area of the CF centre. Consequently, these two positive sites should therefore be treated as high risk, where organisms may be potentially transmitted from environment to patient. As there is now evidence to suggest differences in the virulence and hence clinical outcome of certain of the genomovars of this organism, this study may be important in highlighting the areas that patients who are B. cepacia positive should avoid, to minimise the risk of transmission and acquisition of this organism within the CF cepacia population. These results indicate that effective infection control procedures are required in patients' rooms following physiotherapy, for prevention of B. cepacia transmission and to avoid the transmission of different genomovar types within CF patients, who are already colonised with this pathogen.

Acid pH crystallization of the basic protein lysin from the spermatozoa of red abalone (Haliotis rufescens)

A new crystal form of dimeric red lysin, a distinctly basic protein (M(r) = 16 070) from the red abalone (Haliotis rufescens), has been obtained using ammonium sulfate as precipitant with a sodium citrate-boric acid-citric acid buffer at pH 4.5. The acid pH crystal form resulted from a study aimed at developing conditions favorable to the sitting-drop vapor-diffusion crystallization of other abalone lysins which do not crystallize at neutral or basic pH conditions. The space group is P222(1) with cell dimensions a = 51.2, b = 47.0, c = 123.8 A and two molecules per asymmetric unit.

3D analysis of facial morphology

Dense surface models can be used to analyze 3D facial morphology by establishing a correspondence of thousands of points across each 3D face image. The models provide dramatic visualizations of 3D face-shape variation with potential for training physicians to recognize the key components of particular syndromes. We demonstrate their use to visualize and recognize shape differences in a collection of 3D face images that includes 280 controls (2 weeks to 56 years of age), 90 individuals with Noonan syndrome (NS) (7 months to 56 years), and 60 individuals with velo-cardio-facial syndrome (VCFS; 3 to 17 years of age). Ten-fold cross-validation testing of discrimination between the three groups was carried out on unseen test examples using five pattern recognition algorithms (nearest mean, C5.0 decision trees, neural networks, logistic regression, and support vector machines). For discriminating between individuals with NS and controls, the best average sensitivity and specificity levels were 92 and 93% for children, 83 and 94% for adults, and 88 and 94% for the children and adults combined. For individuals with VCFS and controls, the best results were 83 and 92%. In a comparison of individuals with NS and individuals with VCFS, a correct identification rate of 95% was achieved for both syndromes. This article contains supplementary material, which may be viewed at the American Journal of Medical Genetics website at http://www.interscience.wiley.com/jpages/0148-7299/suppmat/index.html.

Assessing the patterns of health-seeking behaviour and awareness among sleeping-sickness patients in eastern Uganda

For those with sleeping sickness, the consequences of delayed diagnosis include poor prognosis at treatment and an increased risk of tsetse infection. Data on their socio-demographic and clinical characteristics, health-seeking behaviour and delays in presentation and diagnosis were collected from 119 diagnosed cases of rhodesiense sleeping sickness in eastern Uganda. The median total delay, from onset of the illness to diagnosis, was 60 days. The median service-provider delay (30 days) was markedly longer than the median patient delay (17 days). Each of these delays was, however, considerable and independently associated with patients presenting with late-stage sleepiness, giving odds ratios and (95% confidence intervals) of 7.29 (3.10-17.14) and 2.98 (1.38-6.43), respectively. A blood examination at the first visit was also associated with the service-provider delay (odds ratio = 0.45; 95% confidence interval = 0.22-0.95). Most of the patients (77.4%) had either been referred to the local sleeping-sickness hospital by other members of their community or presented at the hospital on their own initiative; few had been referred by other components of the local health system. The results are disappointing, not only in showing long delays in diagnosis (and therefore in treatment) but also in indicating that much of the delay is attributable to the service provider failing to diagnose sleeping sickness among symptomatic individuals.

Paternal germline origin and sex-ratio distortion in transmission of PTPN11 mutations in Noonan syndrome

Germline mutations in PTPN11--the gene encoding the nonreceptor protein tyrosine phosphatase SHP-2--represent a major cause of Noonan syndrome (NS), a developmental disorder characterized by short stature and facial dysmorphism, as well as skeletal, hematologic, and congenital heart defects. Like many autosomal dominant disorders, a significant percentage of NS cases appear to arise from de novo mutations. Here, we investigated the parental origin of de novo PTPN11 lesions and explored the effect of paternal age in NS. By analyzing intronic portions that flank the exonic PTPN11 lesions in 49 sporadic NS cases, we traced the parental origin of mutations in 14 families. Our results showed that all mutations were inherited from the father, despite the fact that no substitution affected a CpG dinucleotide. We also report that advanced paternal age was observed among cohorts of sporadic NS cases with and without PTPN11 mutations and that a significant sex-ratio bias favoring transmission to males was present in subjects with sporadic NS caused by PTPN11 mutations, as well as in families inheriting the disorder.

Measurement of ultrasonic power using an acoustically absorbing well

This paper describes a quick and cost-effective method for constructing a radiation force balance for measuring ultrasonic output power. It utilises a target manufactured from a high-quality acoustical absorber material. The target geometry is in the form of a cup or well that is water-filled and placed directly on the pan of a top-loading chemical balance, thus overcoming the need for the traditional gantry arrangement found in the majority of commercially available balances. The face of the transducer is placed directly in the water contained within the well. This simplification reduces time spent in setting up a balance for measurement, and targets can be manufactured to any required geometry and used on any suitable top-loading balance to measure output power. Within this study, the performance of the absorbing well method was evaluated over the frequency range of 1 MHz to 5 MHz, for acoustic power levels up to 1 W. Power measurements on three transducers were compared with measurements made on the National Physical Laboratory (NPL) primary standard radiation force balance and good agreement is demonstrated between the two systems. At a power of 50 mW, using a chemical balance of resolution 0.1 mg, typical type A (random) uncertainties were +/- 2.0% when expressed at the 95% confidence level.

Interferon-gamma levels in nasopharyngeal secretions of infants with respiratory syncytial virus and other respiratory viral infections

Respiratory syncytial virus (RSV) infection, one of the most common causes of hospitalization of children in developed countries, has been implicated as a cause of asthma. We aimed to characterize the cytokine profile in nasopharyngeal aspirates (NPAs) taken from infants during upper respiratory tract infection to investigate whether RSV induced a unique immune response as compared with other viruses. Additionally, we sought to determine whether this profile was influenced by the infants' atopic status. A prospective birth cohort of babies at high risk of atopy was recruited. Ratios of a T-helper 1 (Th1) cytokine, interferon gamma (IFN-gamma) and a T-helper 2 (Th2)-like cytokine, interleukin-10 (IL-10), in NPAs were determined during episodes of respiratory tract infections in the first year. The viral aetiology of the respiratory tract infections was determined using polymerase chain reaction (PCR), culture and immunofluorescence. Atopic status was ascertained at 1 year of age using skin prick tests. Participants were recruited antenatally and subsequently followed in the community. Sixty babies with one or both parents atopic were enrolled into the study. IFN-gamma : IL-10 ratios in NPAs during upper respiratory tract infections and their correlation with viral aetiology and atopic status were the main outcome measures. The mean IFN-gamma : IL-10 ratio was significantly lower (due to lower IFN-gamma) during RSV infections than during infections with other viruses (P = 0.035). The cytokine ratio, however, did not differ between infants with or without wheeze during URTIs (P = 0.44), or between infants who were atopic or non-atopic (P = 0.49). This study suggests that RSV is associated with lower IFN-gamma production in young babies, regardless of their atopic status, compared to upper respiratory tract infections where either another virus is detected or where no viral identification is made.