How to quantify coughing: correlations with quality of life in chronic cough

Different methods are used for quantifying coughing in sound recordings, but as yet no method has been shown to be more valid than any other. In the present study, the relationships between three different units of cough were examined and their ability to predict subjective ratings of cough and cough-related quality of life were evaluated. In total, 70 subjects (mean+/-SD age 55+/-11.7 yrs, 51 (73%) females) with chronic unexplained cough (median duration 4.8 yrs, interquartile range 2.5-10.1 yrs) performed fully ambulatory 24-h sound recordings, which were manually counted by trained observers and quantified by 1) explosive phases, 2) cough seconds and 3) cough epochs. Subjects also completed cough visual analogue scales (VAS) and the Leicester Cough Questionnaire (LCQ). All units of cough were strongly correlated; explosive phases and cough seconds correlated slightly more strongly than cough seconds with cough epochs or explosive phases with cough epochs. LCQ scores correlated moderately with explosive phases and seconds; epochs correlated slightly less well. Cough VAS scores showed a similar pattern. Explosive phases and seconds are interchangeable units of cough, moderately related to subjective measures and cough-related quality of life; epochs are a less satisfactory alternative.

Predictors of pulmonary exacerbations in patients with cystic fibrosis infected with multi-resistant bacteria

BACKGROUND

This study examined characteristics of adult and adolescent patients with cystic fibrosis (CF) to determine factors associated with an increased risk of pulmonary exacerbations.

METHODS

249 patients with CF infected with multidrug resistant bacteria were recruited and prospectively followed for up to 4.5 years until they experienced a pulmonary exacerbation severe enough to require intravenous antibiotics. Multivariable regression analyses were used to compare the characteristics of patients who experienced an exacerbation with those who did not.

RESULTS

124 of the 249 patients (50%) developed a pulmonary exacerbation during the first year and 154 (62%) experienced an exacerbation during the 4.5 year study period. Factors predictive of exacerbations in a multivariable survival model were younger age (OR 0.98, 95% CI 0.96 to 0.99), female sex (OR 1.45, 95% CI 1.07 to 1.95), lower forced expiratory volume in 1 second (FEV(1)) (OR 0.98, 95% CI 0.97 to 0.99), and a previous history of multiple pulmonary exacerbations (OR 3.16, 95% CI 1.93 to 5.17). Chronic use of inhaled corticosteroids was associated with an increased risk of exacerbation (OR 1.92, 95% CI 1.00 to 3.71) during the first study year.

CONCLUSIONS

Patients who experience pulmonary exacerbations are more likely to be younger, female, using inhaled steroids, have a lower FEV(1), and a history of multiple previous exacerbations. It is hoped that knowledge of these risk factors will allow better identification and closer monitoring of patients who are at high risk of exacerbations.

Is it time to re-assess the role of gliclazide? Targeting insulin resistance in type 2 diabetes patients suboptimally controlled with insulin

BACKGROUND

Adult patients with type 2 diabetes controlled with insulin frequently require the addition of insulin sensitising drugs such as metformin and sometimes glitazones to achieve optimum glycaemic control. Five of a group of eight people with suboptimal diabetes control who were treated by the introduction of gliclazide are reported on. Three patients were excluded. One with type 1 diabetes and two others who had dietary or other therapeutic interventions coinciding with re-introduction gliclazide. Does the re-introduction of gliclazide effect a clinically significant improvement in glycaemic control in type 2 diabetes patients with suboptimal control taking combinations of short and long acting insulin plus metformin?

METHOD

Five adult patients with type 2 diabetes with suboptimal control using combinations of short and long acting insulin plus metformin who were adherent to their dietary regimen were treated by the addition of gliclazide at different doses. Two of the patients were taking pioglitazone in addition to metformin and insulin. Their glycaemic control was monitored over the following six months.

RESULTS

All five showed significant improvement in glycaemic control after three months. Mean reduction in HbA1c was 1.4% (range 0.9% to 2.5%). Six months after the introduction of gliclazide four patients had HbA1c below base line figure and in two patients clinically significant improvement had been maintained.

CONCLUSION

A double blind randomised placebo control study is necessary to evaluate a possible role for gliclazide in type 2 diabetes patients who have suboptimal glycaemic control using combinations of short and long acting insulin plus metformin.

A large field CCD system for quantitative imaging of microarrays

We describe a charge-coupled device (CCD) imaging system for microarrays capable of acquiring quantitative, high dynamic range images of very large fields. Illumination is supplied by an arc lamp, and filters are used to define excitation and emission bands. The system is linear down to fluorochrome densities ≪1 molecule/µm². The ratios of the illumination intensity distributions for all excitation wavelengths have a maximum deviation ∼±4% over the object field, so that images can be analyzed without computational corrections for the illumination pattern unless higher accuracy is desired. Custom designed detection optics produce achromatic images of the spectral region from ∼ 450 to ∼750 nm. Acquisition of a series of images of multiple fluorochromes from multiple arrays occurs under computer control. The version of the system described in detail provides images of 20 mm square areas using a 27 mm square, 2K × 2K pixel, cooled CCD chip with a well depth of ∼10⁵ electrons, and provides ratio measurements accurate to a few percent over a dynamic range in intensity >1000. Resolution referred to the sample is 10 µm, sufficient for obtaining quantitative multicolor images from >30 000 array elements in an 18 mm × 18 mm square.

The value of follow-up after acute Q fever infection

This is a case report of a 53-year-old woman involved in an outbreak of Q fever, in whom Q fever endocarditis was diagnosed 18 months after acute Q fever infection. At the time of diagnosis, she was completely asymptomatic and without screening for chronic Q fever, this severe potentially life-threatening infection would probably not have been recognised until significant valvular destruction had taken place. Early diagnosis enabled prompt, potentially curative medical treatment to start without the need for valvular heart surgery. The authors advocate that serological monitoring should be carried out every 4 months for a period of 2 years after acute Q fever and patients with high phase 1 IgG titres (>800) be investigated further and/or followed more closely depending on the clinical scenario. The case report also discusses the use of complement fixation testing in the diagnosis of Q fever endocarditis. The authors recommend that in cases of culture negative endocarditis, a single negative complement fixation test is not sufficient to exclude the diagnosis of Q fever endocarditis. Micro-immunofluorescence or repeat complement fixation testing is recommended when Q fever endocarditis is suspected clinically.

Clinical implication of routine stone culture in percutaneous nephrolithotomy--a prospective study

OBJECTIVES

To evaluate the correlation between preoperative urine culture (UC) and intraoperative stone culture (SC) and the impact of SC findings on clinical decisions.

METHODS

UC and intraoperative fragmented SC were prospectively obtained in all patients undergoing percutaneous nephrolithotomy between January 2004 and March 2005. Patients with a positive UC received a full course of antibiotics before surgery. All postoperative systemic inflammatory response syndrome (SIRS) events were recorded, as was the antibiotic regimen used and any changes in antibiotic treatment secondary to the SC results.

RESULTS

The study group consisted of 75 consecutive patients. Of these 75 patients, 33 (49%) had sterile UC and SC results. Both urine and renal stones were colonized in 17 patients (24%); in 6 of them, the UC and SC showed different pathogens. A colonized SC associated with a sterile UC was found in 19 patients (25%). The calculated UC sensitivity, specificity, and positive and negative predictive value for the detection of stone colonization was 30%, 94%, and 84% and 58%, respectively. Seventeen patients (22%) had postoperative SIRS. In 13 of them, a change in antibiotic treatment was made according to the SC findings. On univariate analysis, the incidence of SIRS was not related to the length of the operation, stone-free rate, or supracostal or infracostal access. The relative risk of SIRS when the SC was positive was 3.6.

CONCLUSIONS

Renal calculi pathogens are one of the predisposing factors for infectious events; however, preoperative UC often fails to grow stone-colonizing bacteria. Intraoperative SC may be essential in directing the antibiotic regimen postoperatively and should be routinely used.

Vitamin A for acute respiratory infection in developing countries: a meta-analysis

AIM

To determine the efficacy of intervention with high-dose vitamin A as an adjunct to standard treatment on outcome in acute lower respiratory tract infection in children in developing countries.

METHODS

A systematic review of double-blinded, randomized, controlled intervention studies of high-dose vitamin A or placebo in children aged between 1 mo and 6 y presenting with acute non-measles lower respiratory tract infection.

RESULTS

Five studies fulfilling the criteria were identified and included a total of 2177 children (1067 intervention, 1110 control). The main outcome measures were time to normalization of fever, respiratory rate and oxygen dependence, time to discharge, and mortality. On meta-analysis, there were no significant differences in any of the recovery measures or mortality between the intervention and control groups. Pooled results for recovery times are given showing difference in days to recovery days and 95% confidence intervals. Positive summary measures indicate faster recovery in the vitamin A group and negative in the placebo: fever: 0.03 (-0.10 to 0.17); oxygen requirement: -0.08 (-0.31 to 0.16); raised respiratory rate: -0.09 (-0.38 to 0.19); hospital stay: -0.06 (-0.52 to 0.40). Mortality was below 2% in both groups, with a non-significantly higher risk in the intervention group (odds ratio 1.16, 95% CI: 0.61-2.21).

CONCLUSION

There is no evidence from this meta-analysis that intervention with high-dose vitamin A improves recovery from pneumonia in children in developing countries aged from 1 mo to 6 y.

A single amino acid substitution in the envelope protein of chimeric yellow fever-dengue 1 vaccine virus reduces neurovirulence for suckling mice and viremia/viscerotropism for monkeys

A chimeric yellow fever-dengue 1 (ChimeriVax-DEN1) virus was produced by the transfection of Vero cells with chimeric in vitro RNA transcripts. The cell culture supernatant was subjected to plaque purification for the identification of a vaccine candidate without mutations. Of 10 plaque-purified clones, 1 containing no mutation (clone J) was selected for production of the vaccine virus. During subsequent cell culture passaging of this clone for vaccine production, a single amino acid substitution (K to R) occurred in the envelope (E) protein at residue 204 (E204) (F. Guirakhoo, K. Pugachev, Z. Zhang, G. Myers, I. Levenbook, K. Draper, J. Lang, S. Ocran, F. Mitchell, M. Parsons, N. Brown, S. Brandler, C. Fournier, B. Barrere, F. Rizvi, A. Travassos, R. Nichols, D. Trent, and T. Monath, J. Virol. 78:4761-4775, 2004). The same mutation was observed in another clone (clone E). This mutation attenuated the virus in 4-day-old suckling mice inoculated by the intracerebral (i.c.) route and led to reduced viremia in monkeys inoculated by the subcutaneous or i.c. route. The histopathology scores of lesions in the brain tissue of monkeys inoculated with either the E204K or E204R virus were reduced compared to those for monkeys inoculated with the reference virus, a commercial yellow fever 17D vaccine (YF-VAX). Both viruses grew to significantly lower titers than YF-VAX in HepG2, a human hepatoma cell line. After intrathoracic inoculation into mosquitoes, both viruses grew to a similar level as YF-VAX, which was significantly lower than that of their wild-type DEN1 parent virus. A comparison of the E-protein structures of nonmutant and mutant viruses suggested the appearance of new intramolecular bonds between residues 204R, 261H, and 257E in the mutant virus. These changes may be responsible for virus attenuation through a change in the pH threshold for virus envelope fusion with the host cell membrane.

Safety and efficacy of chimeric yellow Fever-dengue virus tetravalent vaccine formulations in nonhuman primates

To construct chimeric YF/DEN viruses (ChimeriVax-DEN), the premembrane (prM) and envelope (E) genes of yellow fever (YF) 17D virus were replaced with those of each wild-type (WT) dengue (DEN) virus representing serotypes 1 to 4. ChimeriVax-DEN1-4 vaccine viruses were prepared by electroporation of Vero cells with RNA transcripts prepared from viral cDNA (F. Guirakhoo, J. Arroyo, K. V. Pugachev, C. Miller, Z.-X. Zhang, R. Weltzin, K. Georgakopoulos, J. Catalan, S. Ocran, K. Soike, M. Ratteree, and T. P. Monath, J. Virol. 75:7290-7304, 2001; F. Guirakhoo, K. Pugachev, J. Arroyo, C. Miller, Z.-X. Zhang, R. Weltzin, K. Georgakopoulos, J. Catalan, S. Ocran, K. Draper, and T. P. Monath, Virology 298:146-159, 2002). Progeny viruses were subjected to three rounds of plaque purifications to produce the Pre-Master Seed viruses at passage 7 (P7). Three further passages were carried out using U.S. current Good Manufacturing Practices (cGMP) to produce the Vaccine Lot (P10) viruses. Preclinical studies demonstrated that the vaccine candidates are replication competent and genetically stable and do not become more neurovirulent upon 20 passages in Vero cells. The safety of a tetravalent vaccine was determined and compared to that of YF-VAX in a formal monkey neurovirulence test. Brain lesions produced by the tetravalent ChimeriVax-DEN vaccine were significantly less severe than those observed with YF-VAX. The immunogenicity and protective efficacy of four different tetravalent formulations were evaluated in cynomolgus monkeys following a single-dose subcutaneous vaccination followed by a virulent virus challenge 6 months later. All monkeys developed low levels of viremia postimmunization, and all the monkeys that had received equal concentrations of either a high-dose (5,5,5,5) or a low-dose (3,3,3,3) formulation seroconverted against all four DEN virus serotypes. Twenty-two (92%) of 24 monkeys were protected as determined by lack of viremia post-challenge. This report is the first to demonstrate the safety of a recombinant DEN virus tetravalent vaccine in a formal neurovirulence test, as well as its protective efficacy in a monkey challenge model.

Laparoscopic splenectomy for lymphoproliferative disease

BACKGROUND

Elective laparoscopic splenectomy (LS) achieves excellent results for benign hematologic diseases. The role of LS for hematologic malignancies is harder to define owing to associated splenomegaly and patient disease that may alter outcome.

METHODS

Retrospective review of single institution experience 1996 through 2002. To limit variability of disease processes, only patients with immune thrombocytopenic purpura (ITP) and lymphoproliferative disease (LPD) were studied.

RESULTS

A total of 211 LS have been performed, including 73 for LPD and 86 for ITP. Patients with LPD were significantly older, 61 vs 46 years p<0.001; male, 45 (62%) vs 33 (38%), p<0.001; and larger splenic weight, 680 vs 162 g, p<0.001. Fifty-nine patients (81%) with LPD were operated with standard LS with a conversion rate of 15%. Hand-assisted LS was performed in 14 patients (19%), and three were converted to open. Compared to ITP, patients with LPD had longer operative time, 148 vs 126 min, p<0001, and higher blood loss, 200 vs 100 cc, p = 0.004. There was one mortality (0.6%), and morbidity occurred in six patients (8%) with LPD and seven (8%) with ITP. The median length of stay was 3 days for LPD and 2 days for ITP, p = 0.03. Forty-six patients were principally operated for a diagnosis, and 27 (60%) were found to have lymphoma.

CONCLUSIONS

LS can be performed safely in patients with LPD, and when used judiciously with hand-assisted techniques can be performed with low conversion and morbidity rates. Splenectomy plays an important role in establishing the diagnosis of lymphoma in LPD.

Menstrual cycle effects on hypothalamic dopamine receptor function in women with a history of puerperal bipolar disorder

Neuroendocrine challenge tests of hypothalamic dopamine receptor function in the early postpartum period suggest that the sensitivity of these receptors is increased in women with a history of bipolar disorder after childbirth. We tested the hypothesis that, in women predisposed to bipolar disorder in the puerperium, hypothalamic dopamine receptor function is more sensitive to changes in circulating ovarian hormone concentrations than in women without such histories. Eight fully recovered and drug-free women who had had at least one episode of bipolar illness following childbirth were compared with nine normal controls. Growth hormone (GH) responses to apomorphine (APO 0.005 mg s.c.) were measured in the early follicular phase, when plasma concentrations of ovarian hormones are low, and in the mid-luteal phase, when they are relatively high. The recovered bipolar subjects and the controls did not differ from each other in their follicular and midluteal oestrogen and progesterone concentrations. In the midluteal phase, both groups had increased oestrogen and progesterone levels. The recovered bipolar subjects did not differ from controls in baseline concentrations of GH in either of the menstrual phases. The APO-GH responses of the two groups did not differ in the follicular phase, but in the midluteal phase, when female sex steroids are relatively increased, the recovered group had significantly enhanced APO-GH responses [MANOVA for repeated measures: (i) area under the curve, group by phase effect: p < 0.04; (ii) GH peak rise after APO, group by phase effect: p < 0.056] and the responses were not related to concurrent measures of mood. The results of this small study of women predisposed to bipolar disorder in the puerperium shows an increased dopaminergic receptor sensitivity in the luteal phase of the menstrual cycle. It suggests that their dopaminergic systems have increased sensitivity to changes in circulating female sex steroids. This may be aetiologically relevant to the pathogenesis of puerperal bipolar disorder.