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PubMed2005

A unique water optional health care personnel handwash provides antimicrobial persistence and residual effects while decreasing the need for additional products.

BACKGROUND: The Centers for Disease Control and Prevention (CDC) has published guidelines for hand hygiene practices, recommending a handwash regimen that alternates between waterless alcohol products and antimicrobial or nonantimicrobial soap and water. The advent of an alcohol-based product that can be used with or without water (ie, water optional) to decontaminate the hands while providing immediacy of kill and antimicrobial persistence could reduce the confusion associated with handwash guidelines. Such a product has been developed, is alcohol-based (61%), and zinc pyrithione (ZPT) preserved (61% alcohol-ZPT) and has proven to be fully compliant with the Food and Drug Administration (FDA) and CDC guidelines. METHODS: FDA-required testing of the 61% alcohol-ZPT product for the health care personnel handwash indication was performed as outlined in the Tentative Final Monograph (TFM) for Health-Care Antiseptic Drug Products, employing waterless and water-aided product applications. It was next assessed for antimicrobial persistence and residual effects by comparing it, in separate waterless and water-aided applications, with commonly available handwashes containing various antimicrobials in a 5-day study employing 49 subjects, in which samples were collected immediately and at 4 hours and 8 hours postapplication. The skin conditioning properties of this formulation were investigated via appropriate methods. RESULTS: The 61% alcohol-ZPT product easily produced >3.0 log 10 reduction in the indicator strain ( Serratia marcescens ) following the first wash, exceeding the 2.0 log 10 FDA requirement. This level of performance was maintained through the tenth wash, surpassing the 3.0 log 10 FDA requirement for the handwash indication. For the assessment of persistence and residual effect in the waterless mode, the water-optional, 61% alcohol-ZPT product consistently produced log 10 reductions of nearly 3.5 or greater at every point over the entire study period. In the water-aided configuration, similar results were obtained as log 10 reductions of 2.5 were observed. The formulation is nonirritating, actually contributing to hand skin condition. CONCLUSIONS: The 61% alcohol-ZPT product exceeds all FDA criteria for the health care personnel handwash indication and is a significant advancement in the concept of skin antisepsis. It represents a single product suitable for use in all hand hygiene settings, demonstrating improved antimicrobial persistence and residual effects. The 61% alcohol-ZPT formulation contributes positively to overall hand conditioning, and a previously reported study has documented it to be virucidal for several DNA and RNA viruses.

Adolescent↗
PubMed2005

Persistence and adherence with topical glaucoma therapy.

PURPOSE: The present study describes the patterns and predictors of treatment persistence and adherence among patients who are diagnosed with glaucoma or as glaucoma suspects (based on claims codes). DESIGN: A retrospective cohort study using health insurance claims data. METHODS: Newly treated individuals with diagnosed glaucoma (n = 3623) and suspect glaucoma (n = 1677) were obtained from healthcare claims data in the Ingenix Research Database. For each of these two diagnostic groups, we calculated the duration of continuous treatment with the initially prescribed medication (persistence) and the prevalence of use of the initial medication at various time points (adherence). Four drug classes were included: beta-blockers, alpha-agonists, carbonic anhydrase inhibitors, and prostaglandin analogs. RESULTS: Nearly one half of the individuals who had filled a glaucoma prescription discontinued all topical ocular hypotensive therapy within six months, and just 37% of these individuals recently had refilled their initial medication at three years after the first dispensing. Prostaglandins were associated with better persistence than any other drug class, which was indicated by hazard ratios for discontinuation of prostaglandins compared with beta-blockers of 0.40 (95% confidence interval, 0.35-0.44) for diagnosed patients and 0.44 (95% confidence interval, 0.37-0.52) for patients with suspect glaucoma. Prostaglandins showed a similar advantage in adherence. Furthermore, patients with diagnosed glaucoma were more likely to adhere to therapy than patients with suspect glaucoma (relative risk = 1.11; 95% confidence interval, 1.05-1.18). CONCLUSION: Persistence and adherence were substantially better with prostaglandins than with other drug classes, and patients with diagnosed open-angle glaucoma were more likely to adhere to treatment than suspected glaucoma.

Administration, Topical↗
PubMed2006

Measurement of persistence and adherence to regimens of IOP-lowering glaucoma medications using pharmacy claims data.

PURPOSE: Determine persistence and adherence of glaucoma patients to therapeutic regimens of prostaglandin/prostamide-class IOP-lowering medications. DESIGN: Retrospective, population-based study. METHODS: Glaucoma patients in the IMS Health LifeLink database with a pharmacy claim for latanoprost (n = 1567), travoprost (n = 381), or bimatoprost (n = 476) between September, 2001 and March, 2002 who had no claims for IOP-lowering medication in the previous 180 days, and who were persistent during the first 90 days of therapy. Values reported in the quantity dispensed and days supply fields of the database were used in an algorithm that corrected anomalous data and adjusted days supply to calculate the main outcome measures, persistence, and adherence to therapy. RESULTS: The percentage of patients persistent for the 12-month observation period was 69.4% (1087/1567) for those prescribed latanoprost, 70.6% (269/381) for those prescribed travoprost, and 68.1% (324/467) for those prescribed bimatoprost. Mean adherence for patients prescribed latanoprost was 75.4% of the year, for those prescribed travoprost, 77.1% of the year, and for those prescribed bimatoprost, 78.2% of the year. The mean number of days adherent for bimatoprost-treated patients (291.2 days) was significantly greater than for latanoprost-treated patients (281.0 days), and not remarkably different from travoprost-treated patients (287.0 days). CONCLUSIONS: Overall, patients in this study who were taking IOP-lowering prostaglandin/prostamide medications had a mean adherence rate of 76% on average, suggesting that opportunities remain for improvement of adherence to therapeutic regimens for glaucoma treatment with prostamides and prostaglandins.

Antihypertensive Agents↗
PubMed2005

Colposcopic and histopathologic evaluation of women participating in population-based screening for human papillomavirus deoxyribonucleic acid persistence.

OBJECTIVE: Evaluation of colposcopic and histopathological findings in women screened for cervical human papillomavirus deoxyribonucleic acid persistence. STUDY DESIGN: A total of 12 527 women, aged 32 to 38 years old, attending the population-based cervical cancer screening program in Sweden were randomized 1:1 to mock testing or human papillomavirus deoxyribonucleic acid testing by general primer 5+/6+ polymerase chain reaction and subsequent typing. Human papillomavirus deoxyribonucleic acid-positive women with a normal Papanicolaou smear (n=341) and an equal number from the control group were human papillomavirus tested on average 19 months later. One hundred nineteen women with type-specific human papillomavirus persistence and 111 controls were referred to colposcopy, and 84.8% attended. RESULTS: Histopathology from colposcopically directed biopsies confirmed cervical intraepithelial neoplasia grade 2 or 3 in 28 of 100 of the women with human papillomavirus deoxyribonucleic acid persistence and in 2 of 95 among controls. CONCLUSION: Among women with normal Papanicolaou smear attending population-based screening, the positive predictive value of human papillomavirus deoxyribonucleic acid persistence for detection of biopsy-confirmed cervical intraepithelial neoplasia 2 or 3 was 29%.

Adult↗
PubMedDate not supplied

Do parents of urban children with persistent asthma ban smoking in their homes and cars?

OBJECTIVE: Environmental tobacco smoke (ETS) increases morbidity for children with asthma. One method to reduce children's ETS exposure is to completely ban smoking in the home and car. We sought to evaluate the degree to which urban children with persistent asthma are protected by household and car smoking bans, and to determine whether health care professionals are counseling parents to implement smoking bans. METHODS: We asked parents of children with asthma to complete an in-person interview including questions about asthma symptoms, smokers in the home, smoking bans (home and car), and the receipt of ETS counseling by health care professionals. RESULTS: We included 231 children with persistent asthma symptoms (response rate 94%). Nearly half of the children lived with a smoker. Overall, only 64% of households had complete restrictions on smoking in the home and car. Even among the children with severe persistent symptoms, less than two-thirds were protected by a complete smoking ban. Among households with smokers, only 51% had a ban on smoking in the home and 49% in the car. The majority of caregivers had been questioned by health care professionals about home smoke exposure; less were asked about exposure in the car (40%) or given suggestions to decrease the child's exposure (58%). CONCLUSIONS: To our knowledge this is the first study to establish the prevalence of smoking bans among children with persistent asthma. Many children with asthma, even those with the most severe symptoms, remain exposed to ETS in the home and in cars. Identifying and reducing smoke exposure among these children should be a health care priority.

Adult↗
PubMed2005

Short-term and long-term asthma control in patients with mild persistent asthma receiving montelukast or fluticasone: a randomized controlled trial.

PURPOSE: To determine whether montelukast is as effective as fluticasone in controlling mild persistent asthma as determined by rescue-free days. SUBJECTS AND METHODS: Participants aged 15 to 85 years with mild persistent asthma (n = 400) were randomized to oral montelukast (10 mg once nightly) or inhaled fluticasone (88 mug twice daily) in a year-long, parallel-group, multicenter study with a 12-week, double-blind period, followed by a 36-week, open-label period. RESULTS: The mean percentage of rescue-free days was similar between treatments after 12 weeks (fluticasone: 74.9%, montelukast: 73.1%; difference = 1.8%, 95% confidence interval [CI]: -3.2% to 6.8%) but not during the open-label period (fluticasone: 77.3%, montelukast: 71.1%; difference = 6.2%, 95% CI: 0.8% to 11.7%). Although both fluticasone and montelukast significantly improved symptoms, quality of life, and symptom-free days during both treatment periods, greater improvements occurred with fluticasone in lung function during both periods and in asthma control during open-label treatment. Post hoc analyses revealed a difference in rescue-free days favoring fluticasone in participants in the quartiles for lowest lung function and greatest albuterol use at baseline. CONCLUSION: In patients with mild persistent asthma, rescue-free days and most asthma control measures improved similarly with fluticasone or montelukast over the short term, but with prolonged open-label treatment, asthma control improved more with fluticasone. Improved asthma control with fluticasone appeared to occur in those with decreased lung function and greater albuterol use at baseline. In the remaining patients, the two treatments appeared to be comparable. These results suggest that classification criteria for mild persistent asthma may need to be re-evaluated.

Acetates↗
PubMed2004

The phylogeny of persistence in DNA.

We continue our study, Poland [Biophysical Chemistry 110 (2004) 59-2], of the distribution of C or G (C-G for short) in the DNA of select organisms, in particular, the tendency for C-G to cluster on all scales with respect to the number of bases considered. We previously found that if we counted the number of C-G bases in consecutive, nonoverlapping boxes containing a total of m bases, then the width of the distribution function describing how many C-G bases are in a box increases with respect to m dramatically relative to the width expected for a random distribution. The relative width of the C-G composition distribution function was found to vary accurately as a power law with respect to m, the size of the box, over a very wide range of m values. We express the power law in terms of a characteristic exponent gamma, that is, the relative widths of the distributions vary as m(gamma). The enhanced relative width of the distribution functions is a direct consequence of the tendency for boxes of similar composition to follow one another. This tendency represents persistence in composition from box to box and hence we refer to gamma as the persistence exponent. The occurrence of a power law means that the tendency for C-G to cluster is present on all scales of sequence length (box size) up to the total length of the chromosome which for bacteria is the entire genome. The persistence exponent gamma that characterizes the power law is thus an important parameter describing the distribution of C-G on all scales from individual base pairs up to the total length of the DNA sample considered. In the present paper, we determine the characteristic exponent gamma and the associated fractal dimension of DNA samples for a selection of species representing all of the major types of organism, that is, we explore the phylogeny of the exponent gamma. Here we treat six prokaryotes and six eukaryotes which, together with the species we have previously treated, brings the total number of species we have examined to 15. We find the power law form for the C-G distribution for all of the species treated and hence this behavior seems to be ubiquitous. The values of the characteristic exponent gamma that we find tend to cluster around the value gamma=0.20 with no obvious pattern with respect to phylogeny. The extreme values that we obtain are gamma=0.057 (yeast) and gamma=0.386 (human). We conclude by showing that the persistence of C-G clustering on the scale of the length of a chromosome is dramatically illustrated by interpreting the C-G distribution as a random walk.

Animals↗
PubMed2003

Memantine attenuates the increase in striatal preproenkephalin mRNA expression and development of haloperidol-induced persistent oral dyskinesias in rats.

Tardive dyskinesia (TD) is a serious motor side effect of long-term neuroleptic treatment that may persist after drug withdrawal. Alterations in striatal enkephalinergic neurons due to excessive glutamatergic activity is a possible pathogenetic mechanism. We studied the effect of the NMDA antagonist memantine in a rat model of TD, in which vacuous chewing movements (VCM) were induced by 20 weeks of haloperidol administration. The striatal density of preproenkephalin mRNA was measured and the number of neurons estimated. Haloperidol induced persistent VCM that was associated with increased striatal expression of preproenkephalin mRNA. Memantine inhibited the development of haloperidol-induced persistent VCM and attenuated the increase in preproenkephalin mRNA expression. This suggests that glutamate-mediated up-regulation of striatal enkephalin plays a role in the development of haloperidol-induced persistent oral dyskinesias.

Analysis of Variance↗
PubMed2006

Prediction of persistent vaginal intraepithelial neoplasia in previously hysterectomized women by high-risk HPV DNA detection.

AIM: To estimate the incidence and latency of Vaginal Intraepithelial Neoplasia (VAIN) in women previously hysterectomized for benign/malign pathology and to evaluate the role of high risk HPVs in the prediction of persistent or recurrent disease. SUBJECTS AND METHODS: 830 women with prior hysterectomy for benign/malign pathologies followed by cytological scraping and vaginal colposcopy. Forty-four patients presented VAIN lesions confirmed by histopathological diagnosis. HPV DNA test was performed at the time of diagnosis. Patients were treated by Laser CO(2) vaporization and underwent follow-up by cytology, colposcopy for a mean period of 3 years. HPV DNA test was performed at 6 months after treatment and every years. Persistent or relapsed disease was confirmed by histopathology. RESULTS: Incidence of VAIN in women hysterectomized for benign pathologies did not differ significantly from the malign group. VAIN degree was more severe in the hysterectomized patients with cervical malignancy and subsequently radiated respect to non-radiated patients. The HPV DNA test at 6 months after VAIN treatment showed fifteen positive cases: twelve HPV 16 (80%) and three HPV 18 (20%). In five cases HPV DNA test was positive with a persistent negative cytological smear during the years. Positivity to high-risk HPV (either 16 or 18) was significantly higher in the patients with relapse to VAIN (10/44, p<0.002). CONCLUSIONS: We suggest to include HPV DNA test in addition to cytology in the follow-up of patients previously treated for VAIN, in order to predict VAIN persistence or progression in vaginal carcinoma before cytology becomes abnormal.

Adult↗
PubMed2007

Complementary and alternative medicine for persistent facial pain.

This article discusses complementary and alternative medicine (CAM), reviews literature on the prevalence of use of CAM by the general adult population in the United States and by patients with persistent facial pain, and summarizes published, peer-reviewed reports of clinical trials assessing the effects of CAM therapies for persistent facial pain. Results indicate that many patients use CAM for musculoskeletal pain, including persistent facial pain. Preliminary work on selected complementary therapies such as biofeedback, relaxation, and acupuncture seems promising; however, there are more unanswered than answered questions about cost-effectiveness, efficacy and mechanisms of action of CAM for persistent facial pain.

Acupuncture Therapy↗
PubMed2006

TBT and TPhT persistence in a sludged soil.

The persistence of tributyltin (TBT) and triphenyltin (TPhT) in soils was studied, taking into consideration the quantity of sewage sludge, TBT and TPhT concentrations in soil as well as the soil pH. The organotin compounds (OTC) were introduced into the soil via a spiked urban sludge, simulating agricultural practise. OTC speciation was achieved after acidic extraction of soil samples followed by gas chromatography-pulsed flame photometric analysis (GC-PFPD). Leaching tests conducted on a spiked sludge showed that more than 98% of TBT are sorbed on the sludge. TBT persistence in soil appeared to depend on its initial concentration in sludge. Thus, it was more important when concentration is over 1000 microg(Sn) kg(-1) of sludge. More than 50% of the initial TBT added into the soil were still present after 2 months, whatever the experimental conditions. The main degradation product appeared to be dibutyltin. About 90% of TPhT were initially sorbed on sludge, whatever the spiking concentration in sludge was. However, TPhT seemed to be quantitatively exchangeable at the solid/liquid interface, according to the leaching tests. It was also significantly degraded in sludged soil as only about 20% of TPhT remain present after 2 months, the monophenyltin being the main degradation product. pH had a significant positive effect on TBT and particularly TPhT persistence, according to the initial amounts introduced into the soil. Thus, at pH over 7 and triorganotin concentration over 100 microg(Sn) kg(-1), less than 10% of TBT but about 60% of TPhT were degraded. When the sludge was moderately contaminated by triorganotins (typically 50 microg(Sn) kg(-1) in our conditions) the pH had no effect on TBT and TPhT persistence.

Organotin Compounds↗
PubMed2006

Increased nodal persistent Na+ currents in human neuropathy and motor neuron disease estimated by latent addition.

OBJECTIVE: To investigate the changes in nodal persistent Na(+) currents in human neuropathy and motor neuron disease. In human motor axons, approximately 1.0% of total Na(+) channels are active at rest, termed "persistent" Na(+) channels, and the conductance can be non-invasively estimated by the technique of latent addition in vivo. METHODS: Latent addition was performed in median motor axons of 93 patients with axonal neuropathy (n=38), lower motor neuron disorder (LMND; n=19) or amyotrophic lateral sclerosis (ALS; n=36) and in 27 age-matched normal subjects. Brief hyperpolarizing conditioning current pulses were delivered, and threshold change at the conditioning-test interval of 0.2 ms was measured as an estimator of the magnitude of persistent Na(+) currents. Threshold electrotonus and supernormality were also measured as indicators of resting membrane potential. RESULTS: Threshold changes at 0.2 ms were significantly greater in patients with neuropathy or LMND (p<0.05), and tended to be greater in ALS patients (p=0.075) than in normal controls. Threshold electrotonus and supernormality did not differ in each patient group and normal controls, suggesting that membrane potential is not altered in patients. In the recovery phase of axonal neuropathy, the threshold changes increased in parallel with an increase in amplitudes of compound muscle action potential. CONCLUSIONS: Persistent Na(+) currents appear to increase commonly in disorders involving lower motor neurons, possibly associated with axonal regeneration or collateral sprouting or changes in Na(+) channel gating. SIGNIFICANCE: The increased axonal excitability could partly be responsible for positive motor symptoms such as muscle cramping frequently seen in lower motor neuron disorders.

Action Potentials↗
PubMed2004

Efficacy, tolerability, and effect on asthma-related quality of life of formoterol bid via multidose dry powder inhaler and albuterol QID via metered dose inhaler in patients with persistent asthma: a multicenter, randomized, double-blind, double-dummy, placebo-controlled, parallel-group study.

BACKGROUND: Inhaled beta(2)-agonists are widely used in asthma treatment. The design limitations of pressurized metered dose inhalers (pMDIs) have prompted the development of dry powder inhalers (DPIs) for the delivery of asthma medications. OBJECTIVE: The goal of this study was to evaluate the efficacy, tolerability, and effect on asthma-related quality of life (QOL) of a long-acting beta(2)-adrenoreceptor agonist, formoterol, delivered via multidose DPI, compared with albuterol delivered via pMDI or placebo in adolescents and adults with persistent asthma. METHODS: This multicenter, randomized, double-blind, double-dummy, placebo-controlled, parallel-group study was conducted in outpatient clinics at 18 US centers. Adolescents and adults with persistent asthma received formoterol 10 pg BID via multidose DPI, albuterol 180 microg QID via pMDI, or placebo for 12 weeks. The primary efficacy variable was the 12-hour AUC of forced expiratory volume in 1 second (FEV(1)) after 12 weeks treatment. Secondary efficacy variables included asthma-related QOL, asthma symptom scores, rescue medication use, and other pulmonary function measures. RESULTS: A total of 239 patients (147 females, 92 males; age range, 13-85 years) with persistent asthma were enrolled (formoterol, n = 80; albuterol, n = 79; placebo, n = 80). Formoterol delivered via the multidose DPI resulted in clinically relevant and statistically significant increases in 12-hour AUC of FEV(1) after 12 weeks of treatment compared with albuterol pMDI and placebo (P < 0.019 and P < 0.001, respectively). Asthma-related QOL (total score) was significantly improved with formoterol treatment compared with placebo (P < 0.015). Nocturnal asthma symptom scores significantly improved with formoterol compared with albuterol and placebo (P < 0.001 and P < 0.003, respectively) and rescue medication use was significantly less with formoterol compared with albuterol and placebo (P < 0.004 and P < 0.002, respectively). Treatment with formoterol was well tolerated. CONCLUSIONS: In this study of adolescents and adults with persistent asthma, 12 weeks of treatment with formoterol 10 microg BID delivered via a multidose DPI provided significantly greater 24-hour bronchodilation compared with albuterol and placebo and resulted in significant improvements in asthma-related QOL compared with placebo. Formoterol was well tolerated in these patients.

Administration, Inhalation↗
PubMed2005

The ties that keep us bound: Top-down influences on the persistence of shape-from-motion.

The phenomenon of perceptual persistence after the motion stops in shape-from-motion displays (SFM) was used to study the influence of prior knowledge on the maintenance of a percept in awareness. In SFM displays an object composed of discontinuous line segments are embedded in a background of randomly oriented lines. The object only becomes perceptible when the line segments that compose the object and the lines that compose the background move in counterphase. Critically, once the movement of the line segments stops, the percept of the object persists for a short period of time. In the present study, perceptual persistence for digits exceeded that reported for nonsense shapes composed of the same line segments. This result is taken as evidence that the processes involved in the persistence of SFM, and therefore sustained perception, are sensitive to top-down influences.

Adult↗
PubMed2006

The cytokine balance in the maintenance of a persistent infection with Salmonella enterica serovar Typhimurium in mice.

ClpXP, serine protease-disrupted mutant of Salmonella enterica serovar Typhimurium chi3306 exhibits attenuated but persistent infection in mice. During infection with S. enterica serovar Typhimurium ClpXP-disrupted mutant, gamma interferon (IFN-gamma) produced by CD4+ cells was up-regulated on day 10 and tumor necrosis factor-alpha (TNF-alpha) produced by CD8+ cells was up-regulated on day 30 after infection. Treatment of monoclonal antibodies against cytokines showed that IFN-gamma and interleukin 10 (IL-10) were involved in maintenance of growth of S. Typhimurium mutant on day 10 after infection, and IFN-gamma, TNF-alpha and transforming growth factor-beta (TGF-beta) were involved in maintenance of growth of this bacterium on day 30 after infection. During persistent infection of S. Typhimurium mutant, IFN-gamma, TNF-alpha, IL-10 and TGF-beta may play different roles to maintain the persistent infection. The cytokine balance might be important in persistent infection with ClpXP-disrupted S. enterica serovar Typhimurium.

Animals↗
PubMed2006

Occurrence and persistence of Bacillus thuringiensis (Bt) and transgenic Bt corn cry1Ab gene from an aquatic environment.

Genetically modified corn crops and suspensions of Bacillus thuringiensis (Bt) are currently used to control pest infestations of insects of the Lepidoptera family. For this purpose, the cry1Ab gene coding for protein delta-endotoxin derived from B. thuringiensis kurstaki (Btk), which is highly toxic to these insects, was inserted and expressed in corn. The aims of this study were to examine the occurrence and persistence of the cry1Ab gene from Btk and Bt corn in aquatic environments near fields where Bt corn was cultivated. First, an optimal DNA preparation and extraction methodology was developed to allow for quantitative gene analysis by real-time polymerase chain reaction (qPCR) in various environmental matrices. Second, surface water and sediment were spiked in vitro with genomic DNA from Bt or Bt corn to evaluate the persistence of cry1Ab genes. Third, soil, sediment, and water samples were collected before seeding, 2 weeks after pollen release, and after corn harvesting and mechanical root remixing in soils to assess cry1Ab gene content. DNA was extracted with sufficient purity (i.e., low absorbance at 230 nm and absence of PCR-inhibiting substances) from soil, sediment, and surface water. The cry1Ab gene persisted for more than 21 and 40 days in surface water and sediment, respectively. The removal of bacteria by filtration of surface water samples did not significantly increase the half-life of the transgene, but the levels were fivefold more abundant than those in unfiltered water at the end of the exposure period. In sediments, the cry1Ab gene from Bt corn was still detected after 40 days in clay- and sand-rich sediments. Field surveys revealed that the cry1Ab gene from transgenic corn and from naturally occurring Bt was more abundant in the sediment than in the surface water. The cry1Ab transgene was detected as far away as the Richelieu and St. Lawrence rivers (82 km downstream from the corn cultivation plot), suggesting that there were multiple sources of this gene and/or that it undergoes transport by the water column. Sediment-associated cry1Ab gene from Bt corn tended to decrease with distance from the Bt cornfield. Sediment concentrations of the cry1Ab gene were significantly correlated with those of the cry1Ab gene in surface water (R=0.83;P=0.04). The data indicate that DNA from Bt corn and Bt were persistent in aquatic environments and were detected in rivers draining farming areas.

Bacillus thuringiensis↗
PubMed2004

Ischemic postconditioning: brief ischemia during reperfusion converts persistent ventricular fibrillation into regular rhythm.

OBJECTIVES: Brief episodes of myocardial ischemia-reperfusion employed during reperfusion after a prolonged ischemic insult may attenuate the total ischemia-reperfusion injury. This phenomenon has been termed ischemic postconditioning. In the present study, we studied the possible effect of postconditioning on persistent reperfusion-induced ventricular fibrillation (VF) in the isolated rat heart model. METHODS: Isolated Langendorff-perfused rat hearts (n = 46) were subjected to 30 min of regional ischemia and reperfusion. The hearts with persistent VF (n = 11) present after 15 min of reperfusion were then randomly assigned into one of the two groups: (1) control hearts (n = 6) in which perfusion was continued without intervention; (2) postconditioned hearts (n = 5) subjected to 2 min of global ischemia followed by reperfusion. Left ventricular pressures, heart rate, coronary flow, and electrogram were monitored throughout the experiment. RESULTS: Conversion of VF into regular rhythm was observed in all hearts subjected to postconditioning. Regular beating was maintained by all postconditioned hearts during the subsequent reperfusion. None of the hearts in the control group had normal rhythm at the end of the experiment. At the end of reperfusion, the left ventricular developed pressure was lower in beating postconditioned hearts compared to the hearts that did not develop persistent VF. CONCLUSIONS: Ischemic postconditioning possesses strong antiarrhythmic effect against persistent reperfusion-induced tachyarrhythmias. Postconditioning may be an interesting, novel adjunct strategy to protect the heart.

Animals↗
PubMed2004

A prospective study of autologous 'blood patch' pleurodesis for persistent air leak after pulmonary resection.

OBJECTIVE: To evaluate the efficacy and risks of autologous 'blood patch' pleurodesis in patients with persistent air leak after pulmonary resection. METHODS: All patients operated on by a single surgeon between January 2002 and January 2004 and presenting with a persistent air leak after pulmonary resection have been treated by the autologous blood patch pleurodesis technique. Fifty millilitres of autologous blood were injected through the chest tube that was then rinsed, clamped for 30 min and then unclamped and placed back to water seal. RESULTS: We have obtained a 100% success rate in 11 patients with persistent air leak who have been treated with this technique over a 2-year period. Most air leaks (72.7%) ceased within 12 h of blood injection. No patient developed empyema, but two patients developed fever and pleural fluid grew Staphylococcus after blood pleurodesis. At 3-month follow-up, all patients were well and their lungs were expanded fully. CONCLUSIONS: In our experience a single injection of 50 ml of blood is sufficient to seal persistent air leaks in less than 48 h. Although highly effective, the autologous blood patch pleurodesis technique should not be used in patients with incomplete lung re-expansion or positive pleural fluid culture to minimize the risk of empyema.

Adult↗