Bone marrow biopsy in the diagnosis of fever of unknown origin in patients with acquired immunodeficiency syndrome

BACKGROUND: Fever is commonly observed in patients with human immunodeficiency virus (HIV) disease and frequently eludes diagnosis. The role of bone marrow biopsy in the diagnosis of fever of unknown origin in patients infected with HIV remains controversial. PATIENTS AND METHODS: One hundred twenty-three consecutive patients with 137 episodes of fever lasting 10 or more days without diagnosis after 1 week of hospitalization were evaluated by bone marrow biopsy. RESULTS: Overall, a specific diagnosis was achieved in 52 episodes by means of culture and histopathological examination (diagnostic yield, 37.9%). Three types of disease were found: mycobacterial infections (n = 36, 69% of documented episodes), including 18 patients with disseminated tuberculosis and 14 with Mycobacterium avium-intracellulare complex infections; non-Hodgkin lymphomas (n = 12, 23%); and visceral leishmaniasis (n = 4, 8%). Although bone marrow cultures were more sensitive than microscopic examination with special stains for the diagnosis of mycobacterial infections, the pathological examination of bone marrow led to a more rapid diagnosis of disease. In addition, the histopathological examination of bone marrow alone led to the diagnosis of a specific condition in 43 episodes (31.3% of all episodes). CONCLUSIONS: Bone marrow biopsy is a useful procedure for the diagnosis of fever in patients with advanced HIV disease, particularly in areas where tuberculosis and leishmaniasis are prevalent. Involvement of the marrow may be the first indication of the existence of extranodal non-Hodgkin lymphoma. For Mycobacterium avium-intracellulare complex infection, blood cultures were more sensitive than bone marrow biopsy.     

Resolution improvement by single-exposure superresolved interferometric microscopy with a monochrome sensor

Single-exposure superresolved interferometric microscopy (SESRIM) by RGB multiplexing has recently been proposed as a way to achieve one-dimensional superresolved imaging in digital holographic microscopy by a single-color CCD snapshot [Opt. Lett. 36, 885 (2011)]. Here we provide the mathematical basis for the operating principle of SESRIM, while we also present a different experimental configuration where the color CCD camera is replaced by a monochrome (B&W) CCD camera. To maintain the single-exposure working principle, the object field of view (FOV) is restricted and the holographic recording is based on image-plane wavelength-dispersion spatial multiplexing to separately record the three bandpass images. Moreover, a two-dimensional extension is presented by considering two options: time multiplexing and selective angular multiplexing. And as an additional implementation, the FOV restriction is eliminated by varying the angle between the three reference beams in the interferometric recording. Experimental results are reported for all of the above-mentioned cases.     

Gallbladder dyskinesia in acalculous biliary colic

AIMS: To test the hypotheses that: 1) postprandial gallbladder emptying might be abnormal in patients with acalculous biliary colic; and 2) that hymecromone, a drug that increases bile flow and relaxes biliary muscle might improve symptoms. METHODS: Twenty-four women were studied. Twelve patients presented recurrent biliary type of pain in the absence of gallstones, and persistence of contrast in the gallbladder, 24 hours after an oral cholecystogram, suggesting cholesterolosis. Twelve healthy volunteers used as controls had no symptoms and the gallbladder was not visible the day after an oral cholecystogram. Gallbladder emptying induced by an oral meal was studied with ultrasound in both groups before and after the administration of hymecromone. RESULTS: Gallbladder volumes were similar in both groups (23 +/- 10 ml vs. 31 +/- 11 ml; NS). Gallbladder emptying in the control group was simple exponential (R2 = 0.948 +/- 0.059) with a rate of 32 +/- 16 minutes. Gallbladder emptying was bimodal in patients. Gallbladder volume increased to 120% in the first 10 minutes, to empty exponentially thereafter (R2 = 0.964 +/- 0.040. Rate: 29 +/- 22 minutes). This resulted in a marked reduction in gallbladder volume emptied at 40 minutes when compared to controls (30% +/- 27% vs. 54% +/- 14%; p = 0.012). Pretreatment of controls with hymecromone induced an emptying pattern similar to that of patients. In patients, emptying after hymecromone did not change but symptoms were improved. CONCLUSIONS: An abnormal emptying pattern of the gallbladder was identified in patients with acalculous biliary colic, and hymecromone was partly effective to reduce pain, despite a minor effect on gallbladder emptying pattern.     

Physicochemical and antioxidant properties of non‐refined sugarcane alternatives to white sugar

Antioxidant properties of commercial sugarcane‐derived products were analysed to study their suitability for being used as functional ingredients. Cane honey, several jaggeries and several brown sugars were selected from the market and analysed in terms of physicochemical characteristics and antioxidant properties, and compared with white refined sugar (twelve products in total). Moisture, water activity, total soluble solids, pH, colour and sugar profile are reported. As for antioxidant properties, total phenols and flavonoid content, as well as antiradical ability (DPPH˙ and the TEAC‐ABTS methods), are given. All sugarcane products contained phenols and flavonoids and exhibited in vitro antioxidant activity, determined by degree of refining. Among the alternatives analysed, jaggeries and cane honey showed the best antioxidant properties. Thermal treatment did not significantly affect the antioxidant capacity of sugarcane products, especially jaggeries. As sugar‐rich products are widely consumed worldwide, the use of non‐refined sugarcane derivatives in food formulation is encouraged.     

Comparison of multicast/broadcast services in Long Term Evolution Advanced and IEEE 802.16m networks

This paper performs a comparison of multicast/broadcast services (MBS) support in Long Term Evolution Advanced (LTE‐A) and Worldwide Interoperability for Microwave Access (WiMAX) IEEE 802.16m. Firstly, the main technical features of both standards concerning MBS operation are presented. It is shown that WiMAX offers higher unicast/MBS multiplexing flexibility as it supports both frequency and time multiplexing schemes, whereas LTE‐A only includes time multiplexing. Besides, only WiMAX supports multi‐antenna transmission. Next, the results of two simulation‐based assessments are presented. In the former, it is considered a scenario with all cells transmitting the same MBS service. The effect of inter‐site distance (ISD) on the maximum MBS data rate is evaluated. Results show that WiMAX configurations outperform LTE‐A for small ISD. This is because WiMAX provides a higher number of resources dedicated to data transmission for the same bandwidth. Furthermore, some WiMAX configurations support two spatially multiplexed data streams. With higher ISDs, LTE‐A outperforms single‐stream WiMAX configurations. In the second assessment, a MBSFN area surrounded by interfering cells is considered to compare unicast/MBS multiplexing performance. The higher maximum MBS data rate is achieved in WiMAX with time division multiplexing, which is precisely the only alternative included in LTE‐A. Copyright © 2012 John Wiley & Sons, Ltd.     

Coronary angioplasty and stenting following heart transplantation with older donors. Is this a rational approach?

The shortage of ideal donor hearts has led to an extension of the classical donor criteria of age. Higher incidence of focal coronary artery disease has been found in this older donor population requiring conventional angioplasty therapy. The authors present two patients with early coronary angiogram post transplantation, requiring angioplasty and stent in the lesions found.     

Joint Dynamic Resource Allocation for QoS Provisioning in Multi-Access and Multi-Service Wireless Systems

This paper proposes a Joint Dynamic Resource Allocation (JDRA) algorithm that allocates simultaneously the best-suited Radio Access Technologies (RATs) and amount of resources to all the users active in a multi-access wireless system. Both distributions are performed at the same time so as to make the most of the heterogeneous network. In this scenario users can connect to several RATs but not simultaneously and, therefore, the JDRA algorithm is able to consider the required handover time in the decision making. Moreover, the algorithm guarantees the Quality of Service (QoS) provision in terms of delay and bit rate in a multi-service scenario where different users may have different QoS requirements. Such a complex optimization problem has been tackled using a Hopfield Neural Network (HNN) formulation. These neural networks have fast response times once hardware implemented, which is very significant since current and future wireless networks must rapidly adapt to changing circumstances in wireless environment and traffic. Results prove the benefits achieved by the usage of the HNN-based JDRA algorithm. Firstly, the joint decision outperforms a two-steps procedure in which, after the RAT selection, the same uni-RAT DRA algorithm is applied. Secondly, the proposed algorithm can deal with different levels of congestion and load distribution among RATs in a much better way that other reference algorithms specifically designed for multi-service scenarios.