Superimposed high-frequency jet ventilation combined with continuous positive airway pressure/assisted spontaneous breathing improves oxygenation in patients with H1N1-associated ARDS

Background

Numerous cases of swine-origin 2009 H1N1 influenza A virus (H1N1)-associated acute respiratory distress syndrome (ARDS) bridged by extracorporeal membrane oxygenation (ECMO) therapy have been reported; however, complication rates are high. We present our experience with H1N1-associated ARDS and successful bridging of lung function using superimposed high-frequency jet ventilation (SHFJV) in combination with continuous positive airway pressure/assisted spontaneous breathing (CPAP/ASB).

Methods

We admitted five patients with H1N1 infection and ARDS to our intensive care unit. Although all patients required pure oxygen and controlled ventilation, oxygenation was insufficient. We applied SHFJV/CPAP/ASB to improve oxygenation.

Results

Initial PaO₂/FiO₂ ratio prior SHFJV was 58-79 mmHg. In all patients, successful oxygenation was achieved by SHFJV (PaO₂/FiO₂ ratio 105-306 mmHg within 24 h). Spontaneous breathing was set during first hours after admission. SHFJV could be stopped after 39, 40, 72, 100, or 240 h. Concomitant pulmonary herpes simplex virus (HSV) infection was observed in all patients. Two patients were successfully discharged. The other three patients relapsed and died within 7 weeks mainly due to combined HSV infection and in two cases reoccurring H1N1 infection.

Conclusions

SHFJV represents an alternative to bridge lung function successfully and improve oxygenation in the critically ill.

Imprinting nanoporous alumina patterns into the magneto-transport of oxide superconductors

We used oxygen ion irradiation to transfer the nanoscale pattern of a porous alumina mask into high-T(C) superconducting thin films. This causes a nanoscale spatial modulation of superconductivity and strongly affects the magneto-transport below T(C), which shows a series of periodic oscillations reminiscent of the Little-Parks effect in superconducting wire networks. This irradiation technique could be extended to other oxide materials in order to induce ordered nanoscale phase segregation.

Coexistence and competition of magnetism and superconductivity on the nanometer scale in underdoped BaFe1.89Co0.11As2

We report muon spin rotation (μSR) and infrared spectroscopy experiments on underdoped BaFe1.89Co0.11As2 which show that bulk magnetism and superconductivity (SC) coexist and compete on the nanometer length scale. Our combined data reveal a bulk magnetic order, likely due to an incommensurate spin density wave (SDW), which develops below T(mag)≈32  K and becomes reduced in magnitude (but not in volume) below Tc=21.7  K. A slowly fluctuating precursor of the SDW seems to develop already below the structural transition at T(s)≈50  K. The bulk nature of SC is established by the μSR data which show a bulk SC vortex lattice and the IR data which reveal that the majority of low-energy states is gapped and participates in the condensate at T≪T(c).

Establishment of a cross-European field site network in the ALARM project for assessing large-scale changes in biodiversity

The field site network (FSN) plays a central role in conducting joint research within all Assessing Large-scale Risks for biodiversity with tested Methods (ALARM) modules and provides a mechanism for integrating research on different topics in ALARM on the same site for measuring multiple impacts on biodiversity. The network covers most European climates and biogeographic regions, from Mediterranean through central European and boreal to subarctic. The project links databases with the European-wide field site network FSN, including geographic information system (GIS)-based information to characterise the test location for ALARM researchers for joint on-site research. Maps are provided in a standardised way and merged with other site-specific information. The application of GIS for these field sites and the information management promotes the use of the FSN for research and to disseminate the results. We conclude that ALARM FSN sites together with other research sites in Europe jointly could be used as a future backbone for research proposals.

Decreased HIV diversity after allogeneic stem cell transplantation of an HIV-1 infected patient: a case report

The human immunodeficiency virus type 1 (HIV-1) coreceptor use and viral evolution were analyzed in blood samples from an HIV-1 infected patient undergoing allogeneic stem cell transplantation (SCT). Coreceptor use was predicted in silico from sequence data obtained from the third variable loop region of the viral envelope gene with two software tools. Viral diversity and evolution was evaluated on the same samples by Bayesian inference and maximum likelihood methods. In addition, phenotypic analysis was done by comparison of viral growth in peripheral blood mononuclear cells and in a CCR5 (R5)-deficient T-cell line which was controlled by a reporter assay confirming viral tropism. In silico coreceptor predictions did not match experimental determinations that showed a consistent R5 tropism. Anti-HIV directed antibodies could be detected before and after the SCT. These preexisting antibodies did not prevent viral rebound after the interruption of antiretroviral therapy during the SCT. Eventually, transplantation and readministration of anti-retroviral drugs lead to sustained increase in CD4 counts and decreased viral load to undetectable levels. Unexpectedly, viral diversity decreased after successful SCT. Our data evidence that only R5-tropic virus was found in the patient before and after transplantation. Therefore, blocking CCR5 receptor during stem cell transplantation might have had beneficial effects and this might apply to more patients undergoing allogeneic stem cell transplantation. Furthermore, we revealed a scenario of HIV-1 dynamic different from the commonly described ones. Analysis of viral evolution shows the decrease of viral diversity even during episodes with bursts in viral load.

Foreign body urethral obstruction in a chimpanzee (Pan troglodytes)

BACKGROUND

A 34-year-old, captive-born, vasectomized male chimpanzee (Pan troglodytes) presented with lethargy and scrotal swelling.

METHODS

Urethral obstruction was diagnosed via urethroscopy.

RESULTS

Removal of the grass stem foreign body resolved the obstruction. Scrotal and preputial ulceration developed from urine scald, which was managed with surgical debridement and antibiotics.

CONCLUSIONS

After 7 weeks, the animal was reintroduced to its troup and has been healthy for 11 months.

Changing incidence and prognostic factors of survival in AIDS-related non-Hodgkin's lymphoma in the era of highly active antiretroviral therapy (HAART)

Non-Hodgkin's lymphoma is an AIDS-defining disease. The impact of HAART on the epidemiology and prognosis is debated controversially. A retrospective analysis has been performed in order to determine the influence of HAART. We collected data of 214 cases of AIDS-related Lymphoma (ARL) treated at our centre from January 1984 until May 2003 and analysed them using the Kaplan-Meier-, log rank- and Cox proportional hazard-model. The incidence of ARL increased between 1991 and 1994 up to a peak of 14.83 per 1000 patient years. In the subsequent periods from 1995 onwards however, it decreased to 3.7 in 1000 patient years. The incidence of AIDS-related primary CNS lymphomas (PCNSL) took a comparable, yet more pronounced development. Using the univariate Kaplan-Meier analysis prolonged survival was significantly associated with the achievement of a complete remission as well as with a favourable virological response to HAART. No significant differences could be shown for the use of protease inhibitors as well as for virological response being achieved before the diagnosis of NHL. When using the Cox model, complete remission overrides viral response and thus remained the only independent prognostic factor. Classical prognostic factors (CD4 count, prior Kaposi Sarcoma, extranodal manifestation, staging and histological subtype of NHL) were no longer significant for HAART patients in the multivariate analysis. These results illustrate the requirement for new prospective studies in order to determine the best options and ideal timing of coadministering chemotherapy and the type of HAART. Furthermore this study demonstrates that HAART decreases the incidence of ARL, and that achievement of a complete remission in patients suffering from ARL is--according to the multivariate analysis--the single most important prognostically relevant factor with respect to the time of survival.

[MRI-based flow measurements in the main pulmonary artery to detect pulmonary arterial hypertension in patients with cystic fibrosis]

PURPOSE

Development of pulmonary arterial hypertension (PH) is a common problem in the course of patients suffering from cystic fibrosis (CF). This study was performed to evaluate MRI based flow measurements (MR(venc); Velocity ENCoding) to detect signs of an evolving PH in patients suffering from CF.

MATERIALS AND METHODS

48 patients (median age: 16 years, range: 10 - 40 years, 25 female) suffering from CF of different severity (mean FEV (1): 74% +/- 23, mean Shwachman-score: 63 +/- 10) were examined using MRI based flow measurements of the main pulmonary artery (MPA). Phase-contrast flash sequences (TR: 9.6 ms, TE: 2.5 ms, bandwidth: 1395 Hertz/Pixel) were utilized. Results were compared to an age- and sex-matched group of 48 healthy subjects. Analyzed flow data where: heart frequency (HF), cardiac output (HZV), acceleration time (AT), proportional acceleration time related to heart rate (ATr), mean systolic blood velocity (MFG), peak velocity (Peak), maximum fow (Fluss(max)), mean flow (Fluss(mitt)) and distensibility (Dist).

RESULTS

The comparison of means revealed significant differences only for MFG, Fluss(max) and Dist, but overlap was marked. However, using a scatter-plot of AT versus MFG, it was possible to identify five CF-patients demonstrating definite signs of PH: AT = 81 ms +/- 14, MFG = 46 +/- 11 cm/s, Dist = 41% +/- 7. These CF-patients where the most severely affected in the investigated group, two of them were listed for complete heart and lung transplantation. The comparison of this subgroup and the remaining CF-patients revealed a highly significant difference for the AT (p = 0.000001) without overlap.

CONCLUSION

Screening of CF-patients for the development of PH using MRvenc of the MPA is not possible. In later stages of disease, the quantification of AT, MFG and Dist in the MPA may be useful for the detection, follow-up and control of therapy of PH. MR(venc) of the MPA completes the MRI-based follow-up of lung parenchyma damage in patients suffering from CF.

Results of the performance verification of the CoaguChek XS system

BACKGROUND

This is the first paper reporting a performance verification study of a point-of-care (POC) monitor for prothrombin time (PT) testing according to the requirements given in chapter 8 of the International Organization for Standardization (ISO) 17593:2007 standard "Clinical laboratory testing and in vitro medical devices - Requirements for in vitro monitoring systems for self-testing of oral anticoagulant therapy". The monitor under investigation was the new CoaguChek XS system which is designed for use in patient self testing. Its detection principle is based on the amperometric measurement of the thrombin activity generated by starting the coagulation cascade using a recombinant human thromboplastin.

METHODS

The system performance verification study was performed at four study centers using venous and capillary blood samples on two test strip lots. Laboratory testing was performed from corresponding frozen plasma samples with six commercial thromboplastins. Samples from 73 normal donors and 297 patients on oral anticoagulation therapy were collected. Results were assessed using a refined data set of 260 subjects according to the ISO 17593:2007 standard.

RESULTS

Each of the two test strip lots met the acceptance criteria of ISO 17593:2007 versus all thromboplastins (bias -0.19 to 0.18 INR; >97% of data within accuracy limits). The coefficient of variation for imprecision of the PT determinations in INR ranged from 2.0% to 3.2% in venous, and from 2.9% to 4.0% in capillary blood testing. Capillary versus venous INR data showed agreement of results with regression lines equal to the line of identity.

CONCLUSION

The new system demonstrated a high level of trueness and accuracy, and low imprecision in INR testing. It can be concluded that the CoaguChek XS system complies with the requirements in chapter 8 of the ISO standard 17593:2007.