Automated system for capture and detection of nucleic acids.

A fully automated nucleic acid analysis system is described, which offers positive sample identification, improved sensitivity and reduced user interaction compared to conventional techniques. The system relies on the sequence-specific capture of DNA onto solid-phase particles, confirming product identity without the problems of interpretation and lack of sequence information inherent in gel-based analyses. The system can be used for sequence confirmation, mutation analysis and semiquantitative detection of PCR products.

Experience with independent radiological review during a topotecan trial in ovarian cancer.

BACKGROUND: The results of phase II clinical trials are usually based on response of tumours to new oncolytic agents as evidenced by radiological imaging techniques. In this trial, all claimed responders were reviewed at a specially convened meeting by the peer group of study investigators and a radiologist, independent of the study institutions. PATIENTS AND METHODS: One hundred eleven patients with advanced epithelial ovarian cancer who had previously been treated with a platinum based regimen and had subsequently relapsed and who had measurable disease were treated with topotecan at a dose of 1.5 mg/m2/day i.v. on five consecutive days repeated every 21 days to assess efficacy and tolerability. Ninety-three were considered eligible for the study per protocol and lesions were assessed by either computerised tomography (CT) or ultrasound (US). At the meeting, scans from all 24 (25.8%) claimed responders were reviewed, lesions remeasured by the radiologist and a group discussion led to a final response classification. RESULTS: Ninety-two patients were found to be eligible for the study and 14 (15.2%) were confirmed as responders. Ten were rejected as responders, mainly because the lesion did not decrease in size by < or = 50%, but one patient failed to meet the entry criteria. Remeasurement of CT scans was more objective than US scans. Difficulties were encountered during review of some CT scan sequences because of non-uniform imaging parameters. CONCLUSIONS: Independent radiological review in conjunction with the peer review group in this trial enabled rigorous and consistent application of response criteria. This decreased the response rate from 25.8% to 15.2%, but this represents a more objective assessment. CT scanning is an objective technique for assessing response rates in phase II studies whereas US is subjective and dose not necessarily allow accurate lesion assessment on subsequent examinations, nor allows independent review at a later date. For these reasons it should not be used in such studies for accurate lesion assessment. Cross-sectional imaging techniques such as CT and magnetic resonance imaging (MRI) do allow accurate lesion assessment and independent review at a later date, but standard protocols need to be instituted, to allow consistency and a comparison to be made with subsequent studies using the same agent and a broad comparison to be made with other agents.

The efficacy of intranasal mupirocin in the prevention of staphylococcal infections: a review of recent experience.

Staphylococcal infections remain an important cause of morbidity and mortality. Methicillin-resistant Staphylococcus aureus (MRSA) present a particular problem because of the costs of treatment and containing outbreaks. The role of nasal carriage of staphylococci in the epidemiology of staphylococcal infection has been recognized for over 30 years. Until recently, eradication of nasal carriage of S. aureus has proved difficult, with a variety of topical and systemic agents yielding poor results with either little discernible effect on nasal carriage or rapid recolonization. Mupirocin is a novel topical antibiotic with excellent antibacterial activity against staphylococci, including MRSA. Intranasal administration of calcium mupirocin has achieved excellent results in the eradication of nasal carriage of S. aureus and producing an associated reduction in S. aureus infection in a variety of clinical settings, including MRSA outbreaks, neonatal nurseries, haemodialysis, cardiothoracic surgery and familial staphylococcal infections. This article reviews the efficacy and safety of intranasal mupirocin in the prevention of staphylococcal infections.

Total circulating red cells versus haematocrit as the primary descriptor of oxygen transport by the blood.

Peripheral haematocrit (PCV) is the traditional target and monitor in many transfusion regimens. Without negating the importance of PCV as a determinant of whole blood viscosity, the present article outlines two important reasons why the red cell volume (RCV) should replace PCV in the central target role during blood transfusion in intensive care and other emergency situations: 1. PCV reflects both RCV and plasma volume (PV) and is therefore not directly proportional to the total blood oxygen carrying capacity. At best, the relationship between PCV and RCV is hyperbolic and this is often overlooked when relating the two parameters in practice. At worst, the hyperbolic relationship is unreliable because PV and RCV can vary independently and the PCV is a fluctuating ratio of variable numbers. 2. PCV is not a good indicator of blood volume (BV), which is another important determinant of oxygen delivery to tissues and a crucial parameter in intensively managed patients. BV is directly proportional to RCV and this relationship also is often overlooked in clinical practice. The recommended values for RCV are 30 ml/kg in men. 25 ml/kg in women and between 30 ml/kg and 45 ml/kg in neonates within the first week of life.

Biotin labeling of red cells in the measurement of red cell volume in preterm infants.

Determination of circulating red cell volume (RCV) in anemic preterm infants is, in theory, a better indicator of transfusion needs than Hb concentration. Our study reports the results of RCV measurement using biotin labeling of red cells on 40 occasions in preterm infants of 25-34 wk gestation. In 20 infants, who had estimations made within 24 h of birth, the RCV varied between 17.7 and 66 mL/kg. Twenty measurements were made at a later age at the time of a blood transfusion. RCV values were between 13.1 and 41.5 mL/kg before transfusion. In 13 infants, RCV was determined simultaneously using two methods, biotin and dilution of autologous HbF with donor HbA at transfusion. There was no significant difference between the results of RCV estimations using these two methods. Our study demonstrates that biotin labeling is an effective method for determining RCV in preterm infants.

Increased concentrations of D-dimers in newborn infants.

The concentrations of D-dimers (the D fragments of fibrinogen) were measured in blood from 15 preterm infants, and 45 born at full term, to establish normal ranges. The adult normal range is less than 0.25 mg/l; 31 of the 60 infants (52%) had values less than 0.25 mg/l, in 16 (27%) they were 0.25-0.5, in eight (13%) 0.5-1, in three (5%) 1-2, and in two (3%) 2-4. D-dimer concentrations measured during the neonatal period should be interpreted with caution.