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High-performance semiconductor continous-wave (CW) sources are demonstrated in this paper, which include a Fabry-Perot (FP) laser oscillator (LO) with relative intensity noise (RIN) < - 165 dB/Hz at frequencies above 500 MHz, and a tapered semiconductor optical amplifier with 35.dB gain, a maximum output power of 820 mW, and RIN [approximately equal to] - 155 dB/Hz at microwave frequencies. These are used in suboctave-bandwidth analog links to demonstrate link performance comparable to that available with solid-state laser sources. Index Terms - Laser noise, optical analog links, optical modulation, semiconductor lasers, semiconductor optical amplifiers.

Multiple quantum-well InGaAs-AlGaAs ridge-waveguide diode lasers have been made in uniform linear arrays of strained-layers, working at around 980 nanometers. A study of effects of cavity length, ridge width and cladding outside the ridge t, on threshold current (I(sub th)) and differential quantum efficiencies (eta(sub d)) shows that, t must be manipulated between 90-240 nanometers to get I(sub th) of 6-7 milli A and eta(sub d) > 40% per facet. Lasers with short cavity range were used to obtain threshold and efficiencies for narrow ridge width.

Background In the 1960s, it was reported that infectious complications were the main cause of fever during neutropenia that followed hematopoietic stem cell transplant ( HSCT). More recently, mucositis has become recognized as an important determinant of the inflammatory response and infectious complications. Methods The objective of this prospective study was to determine the impact of intestinal mucositis, as measured by plasma citrulline, and neutropenia on the systemic inflammatory response (C-reactive protein) and the occurrence of bacteremia among 2 cohorts of HSCT recipients: 1 composed of 18 patients who had been treated with a myeloablative ( MA) regimen (high-dose melphalan) and the other involving 19 patients who had received the non-myeloablative ( NMA) regimen (fludarabine and cyclophosphamide). Blood cultures were obtained for surveillance from admission onwards as well as at the onset of fever. Results The MA regimen induced severe intestinal mucositis manifest by citrullinemia <10 μmol/L, which was accompanied by an inflammatory response, and bacteremia affected 8 (44%) of 18 patients and coincided with the nadir of citrullinemia. By contrast, those who had been treated with the NMA regimen did not develop severe intestinal mucositis, had a moderate inflammatory response, and only 2 (11%) of the 19 patients developed bacteremia. However, both groups experienced profound neutropenia and its duration was significantly longer for those receiving the NMA regimen. Conclusion This study suggests that severe intestinal mucositis, i.e., citrullinemia <10 μmol/L, defines the period of risk of bacteremia better than does neutropenia, and that measuring plasma citrulline may prove useful in deciding who needs empirical antimicrobial therapy and when. [ABSTRACT FROM AUTHOR]

VAN VLIET M., POTTING C.M.J., STURM P.D.J., DONNELLY J.P. & BLIJLEVENS N.M.A. (2011) European Journal of Cancer Care 20, 679-685 How prompt is prompt in daily practice? Earlier initiation of empirical antibacterial therapy for the febrile neutropenic patient With fever being the most common manifestation of early sepsis, clinical practice guidelines emphasise the prompt institution of broad-spectrum antibacterial therapy at its onset. An audit was performed on the haematology ward to determine whether there was any delay in starting antibiotic treatment during neutropenia in clinical patients and to define the main reasons for this. Strategies were developed, implemented and evaluated on short- and long-term implications on the delay in the start of antibacterial therapy. The procedures specified in the protocol for starting empirical antibacterial therapy were audited to assess whether the target for starting therapy within 30 min of fever was achieved. Initial results indicated that two major changes to the protocol were necessary to achieve a reduction in the delay between detection of fever and starting antibacterial therapy. This modified protocol was evaluated 4 months after implementation by means of a consecutive audit. After 3 years, a third audit was performed to determine the long-term implications of the improved protocol. In the initial audit, the mean time interval between the onset of fever and the administration of antibacterial therapy was 75 min. With the modified protocol, the mean time to starting therapy was shortened to 32 min ( P < 0.05). Changing the protocol for starting antibacterial therapy allowed nurses to administer the first dose of antibiotic significantly earlier. [ABSTRACT FROM AUTHOR]

Arrays of InP-based avalanche photodiodes (APDs) with InGaAsP absorber regions have been fabricated and characterized in the Geiger mode for photon-counting applications. Measurements of APDs with InGaAsP absorbers optimized for 1.06 mum wavelength show dark count rates (DCRs) <20 kHz for room-temperature operation with photon detection efficiency (PDE) up to 50% and a reset or dead time of 1s. APDs with InGaAs absorbers optimized for 1.55 mum wavelength and 240 K temperature have DCRs <20 kHz, PDE up to 45%, and a reset time of ~6 mus. Arrays for both wavelengths have been fabricated and packaged with GaP microlenses (of 100 and 50 mum pitch) and CMOS readout integrated circuits (ROICs). Comparisons are made between ROICs that operate in the framed-readout mode as well as those that operate in continuous-readout mode. [ABSTRACT FROM PUBLISHER]

The inhibition of nuclear factor kappa B (NF-?B) by, for instance, curcumin is becoming an important new approach in combination with chemotherapy or irradiation for the treatment of a variety of cancers including haematological malignancies. A dose-limiting side effect of anticancer therapy in the gastrointestinal tract is mucosal barrier injury. It is hypothesised that mucosal barrier injury is initiated and amplified by proinflammatory-and NF-?B-regulated mediators. Therefore, the effect of NF-?B inhibition was studied in the onset of mucosal barrier injury. In response to cytostatic drug treatment (arabinoside cytosine (Ara-C) and methotrexate (MTX)), NF-?B was activated in intestinal epithelial cells (IEC-6) resulting in an NF-?B-related induction of tumour necrosis factor alpha and monocyte chemoattractant protein-1. NF-?B inhibition increased the susceptibility of IEC-6 cells to Ara-C as well as MTX-induced cell death when obtained by the addition of caffeic acid phenethyl ester (CAPE), but not using curcumin. In an animal model for MTX-induced mucosal barrier injury, the induction of NF-?B-related cytokines and chemokines was detected upon treatment with MTX. Despite increased susceptibility shown in vitro, the inhibition of NF-?B resulted in a partial amelioration of villous atrophy normally seen in the small intestine upon MTX treatment. These results show that the inhibition of NF-?B does not increase intestinal side effects of the anticancer treatment, suggesting a safe use of curcumin and CAPE in combination with anticancer treatment.Leukemia (2004) 18, 276-284. doi:10.1038/sj.leu.2403233 Published online 11 December 2003 [ABSTRACT FROM AUTHOR]

Abstract: As more indications continue to be found for allogeneic haematopoietic transplantation, more patients are at risk for invasive fungal infectious diseases (IFID), particularly candidiasis and aspergillosis. Risk factors for disease are becoming better defined and diagnostic methods have improved considerably. In addition, there is now international agreement that three elements form the basis for defining IFID (host factors, clinical evidence, and mycological results), that imaging is acceptable for diagnosing disease, and that indirect tests such as antigen detection are also adequate mycological proof of cause. There are also more drugs available and still more to come, offering the potential for selective prophylaxis as well as preemptive and specific therapy, as well as for flexible administration. Hence, all the elements are in place for designing and testing an effective and economically sound strategy for dealing with IFID. [ABSTRACT FROM AUTHOR]