Lab on a Chip for the Colorimetric Determination of Nitrite in Processed Meat Products in the Jordanian Market.

Nitrite and Nitrate have been used extensively as additives in various meat products to enhance flavor, color, and to preserve the meat from the bacterial growth. High concentrations of nitrite can threat human health since several studies in the literature claim that nitrite is associated with cancer incidences, leukemia, and brain tumors. Therefore, it is vital to measure the nitrite concentrations in processed meat products. In this study, an in-lab miniaturized photometric detection system is fabricated to inspect the nitrite concentration in processed meat products in Jordan. The analytical performance of nitrite detection is evaluated based on three key statistical parameters; linearity, limit of detection, and limit of quantitation. Respectively, for the fabricated system, the three values are found to be equal to 0.995, 1.24 × 10-2 ppm, and 4.12 × 10-2 ppm. Adherence to Beer's law is found over the investigated range from 2.63 ppm to 96.0 ppm. The developed system is utilized for photometric detection of nitrite in processed meat products available in the Jordanian market like pastrami, salami, and corned beef. In all of the analyzed samples, the nitrite content is found to be lower than 150 ppm, which represents the maximum allowable nitrite limit.

Characterization of oxygen transfer in vertical microbubble columns for aerobic biotechnological processes.

This paper presents the applicability of a microtechnologically fabricated microbubble column as a screening tool for submerged aerobic cultivation. Bubbles in the range of a few hundred micrometers in diameter were generated at the bottom of an upright-positioned microdevice. The rising bubbles induced the circulation of the liquid and thus enhanced mixing by reducing the diffusion distances and preventing cells from sedimentation. Two differently sized nozzles (21 × 40 µm(2) and 53 × 40 µm(2) in cross-section) were tested. The gas flow rates were adjustable, and the resulting bubble sizes and gas holdups were investigated by image analysis. The microdevice features sensor elements for the real-time online monitoring of optical density and dissolved oxygen. The active aeration of the microdevice allowed for a flexible oxygen supply with mass transfer rates of up to 0.14 s(-1). Slightly higher oxygen mass transfer rates and a better degassing were found for the microbubble column equipped with the smaller nozzle. To validate the applicability of the microbubble column for aerobic submerged cultivation processes, batch cultivations of the model organism Saccharomyces cerevisiae were performed, and the specific growth rate, oxygen uptake rate, and yield coefficient were investigated.

Behçet's disease, painful genital ulcerations and steroid pulse therapy.

Behçet's disease (BD) is a rare cause of painful genital ulcerations. It is a chronic condition in which the acute phases come and go with varying intensity. Mouth ulcers are the most common and earliest sign of BD. Other manifestations include genital ulcers, skin lesions and uveitis. The disease may also affect blood vessels, gastrointestinal tract, respiratory tract and the central nervous system.

Acute paraplegia in a patient with AIDS and a normal CSF examination.

We report a case of tuberculous myeloradiculitis in a patient with AIDS. The case highlights the difficulty in reaching a diagnosis for the neurological symptoms of a patient with a normal CSF examination and the need for HIV screening of immune-compromised patients with myeloradiculitis.

Urine based screening for asymptomatic/undiagnosed genital chlamydial infection in young people visiting the accident and emergency department is feasible, acceptable, and can be epidemiologically helpful.

OBJECTIVE: To assess the acceptability and the feasibility of urine based Chlamydia trachomatis screening in asymptomatic young people aged 16-35 years attending an inner city accident and emergency (A&E) department. DESIGN: Cross sectional study. SETTING: A&E department in a teaching hospital, in south London, UK. METHOD: From July to November 2001 a urine based chlamydia screening test was offered to 719 consecutive A&E attendees aged 16-35 years and their companions. Participants were given an information sheet and were asked to complete a demographic and sexual health questionnaire. Following informed consent, eligible participants provided first pass urine specimens. Specimens were tested for C. trachomatis using nucleic acid amplification. RESULTS: Of the A&E attendees asked, 76.5% (550/719) agreed to participate. Prevalence of genital chlamydial infection was 4.2% (18/432; 95% confidence interval (CI) 2.5 to 6.6). 12 of the positive participants (66.7%; 95% CI 40.99 to 86.65) were women, of whom seven were Afro-Caribbean. Nine of the chlamydia positive participants (50%; 95% CI 26.0 to 73.9) were aged 25 years. Three of the positive urine specimens were from companions, of whom a total of 143 were screened. All the positive participants were contactable, and were offered treatment. CONCLUSION: Urine based screening for undiagnosed genital chlamydial infection in the A&E department was acceptable and feasible. The department provides a unique site for screening young patients and companions, men and women.

Atypical presentation of HIV seroconversion illness in a young woman.

Early detection and counselling of HIV-infected individuals can have an impact on prevention of HIV transmission. We describe an atypical presentation of an HIV seroconversion illness in a woman.

Is acute appendicitis another inflammatory condition associated with highly active antiretroviral therapy (HAART)?

OBJECTIVE: To report the occurrence of acute appendicitis as a possible manifestation of the immune restoration inflammatory syndrome (IRIS) following the commencement of highly active antiretroviral therapy (HAART) in HIV patients. DESIGN: Case-note review of HIV patients on HAART with acute appendicitis. METHODS: Review of HIV markers, antiretroviral therapy and abdominal ultrasound results of four HIV patients with acute appendicitis and the histopathology reports on the appendix in two of the patients. RESULTS: From a population of approximately 350 HIV patients on HAART, we found four patients who developed acute appendicitis within 6 months of commencing or changing HAART. CONCLUSION: Acute appendicitis occurring in HIV patients on HAART may represent a variant of IRIS. Further immunohistopathological and epidemiological evaluation will be needed to define this relationship fully.